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-rw-r--r--net/dccp/Kconfig1
-rw-r--r--net/dccp/ackvec.c163
-rw-r--r--net/dccp/ackvec.h62
-rw-r--r--net/dccp/ccid.c8
-rw-r--r--net/dccp/ccid.h37
-rw-r--r--net/dccp/ccids/Kconfig30
-rw-r--r--net/dccp/ccids/ccid2.c228
-rw-r--r--net/dccp/ccids/ccid2.h21
-rw-r--r--net/dccp/ccids/ccid3.c710
-rw-r--r--net/dccp/ccids/ccid3.h41
-rw-r--r--net/dccp/ccids/lib/Makefile2
-rw-r--r--net/dccp/ccids/lib/loss_interval.c352
-rw-r--r--net/dccp/ccids/lib/loss_interval.h64
-rw-r--r--net/dccp/ccids/lib/packet_history.c599
-rw-r--r--net/dccp/ccids/lib/packet_history.h220
-rw-r--r--net/dccp/ccids/lib/tfrc.c63
-rw-r--r--net/dccp/ccids/lib/tfrc.h29
-rw-r--r--net/dccp/dccp.h35
-rw-r--r--net/dccp/feat.c29
-rw-r--r--net/dccp/feat.h26
-rw-r--r--net/dccp/input.c155
-rw-r--r--net/dccp/ipv4.c12
-rw-r--r--net/dccp/ipv6.c10
-rw-r--r--net/dccp/minisocks.c33
-rw-r--r--net/dccp/options.c139
-rw-r--r--net/dccp/output.c55
-rw-r--r--net/dccp/proto.c194
-rw-r--r--net/dccp/sysctl.c36
-rw-r--r--net/dccp/timer.c5
29 files changed, 1777 insertions, 1582 deletions
diff --git a/net/dccp/Kconfig b/net/dccp/Kconfig
index 0549e47..7aa2a7a 100644
--- a/net/dccp/Kconfig
+++ b/net/dccp/Kconfig
@@ -1,6 +1,7 @@
menuconfig IP_DCCP
tristate "The DCCP Protocol (EXPERIMENTAL)"
depends on INET && EXPERIMENTAL
+ select IP_DCCP_CCID2
---help---
Datagram Congestion Control Protocol (RFC 4340)
diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c
index 83378f3..6de4bd1 100644
--- a/net/dccp/ackvec.c
+++ b/net/dccp/ackvec.c
@@ -30,7 +30,7 @@ static struct dccp_ackvec_record *dccp_ackvec_record_new(void)
kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
if (avr != NULL)
- INIT_LIST_HEAD(&avr->dccpavr_node);
+ INIT_LIST_HEAD(&avr->avr_node);
return avr;
}
@@ -40,7 +40,7 @@ static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr)
if (unlikely(avr == NULL))
return;
/* Check if deleting a linked record */
- WARN_ON(!list_empty(&avr->dccpavr_node));
+ WARN_ON(!list_empty(&avr->avr_node));
kmem_cache_free(dccp_ackvec_record_slab, avr);
}
@@ -52,16 +52,15 @@ static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
* just add the AVR at the head of the list.
* -sorbo.
*/
- if (!list_empty(&av->dccpav_records)) {
+ if (!list_empty(&av->av_records)) {
const struct dccp_ackvec_record *head =
- list_entry(av->dccpav_records.next,
+ list_entry(av->av_records.next,
struct dccp_ackvec_record,
- dccpavr_node);
- BUG_ON(before48(avr->dccpavr_ack_seqno,
- head->dccpavr_ack_seqno));
+ avr_node);
+ BUG_ON(before48(avr->avr_ack_seqno, head->avr_ack_seqno));
}
- list_add(&avr->dccpavr_node, &av->dccpav_records);
+ list_add(&avr->avr_node, &av->av_records);
}
int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
@@ -69,9 +68,8 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
struct dccp_sock *dp = dccp_sk(sk);
struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
/* Figure out how many options do we need to represent the ackvec */
- const u16 nr_opts = DIV_ROUND_UP(av->dccpav_vec_len,
- DCCP_MAX_ACKVEC_OPT_LEN);
- u16 len = av->dccpav_vec_len + 2 * nr_opts, i;
+ const u16 nr_opts = DIV_ROUND_UP(av->av_vec_len, DCCP_MAX_ACKVEC_OPT_LEN);
+ u16 len = av->av_vec_len + 2 * nr_opts, i;
u32 elapsed_time;
const unsigned char *tail, *from;
unsigned char *to;
@@ -81,7 +79,7 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
return -1;
- delta = ktime_us_delta(ktime_get_real(), av->dccpav_time);
+ delta = ktime_us_delta(ktime_get_real(), av->av_time);
elapsed_time = delta / 10;
if (elapsed_time != 0 &&
@@ -95,9 +93,9 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
to = skb_push(skb, len);
- len = av->dccpav_vec_len;
- from = av->dccpav_buf + av->dccpav_buf_head;
- tail = av->dccpav_buf + DCCP_MAX_ACKVEC_LEN;
+ len = av->av_vec_len;
+ from = av->av_buf + av->av_buf_head;
+ tail = av->av_buf + DCCP_MAX_ACKVEC_LEN;
for (i = 0; i < nr_opts; ++i) {
int copylen = len;
@@ -116,7 +114,7 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
to += tailsize;
len -= tailsize;
copylen -= tailsize;
- from = av->dccpav_buf;
+ from = av->av_buf;
}
memcpy(to, from, copylen);
@@ -134,19 +132,19 @@ int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
* buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
* equal buf_nonce.
*/
- avr->dccpavr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
- avr->dccpavr_ack_ptr = av->dccpav_buf_head;
- avr->dccpavr_ack_ackno = av->dccpav_buf_ackno;
- avr->dccpavr_ack_nonce = av->dccpav_buf_nonce;
- avr->dccpavr_sent_len = av->dccpav_vec_len;
+ avr->avr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
+ avr->avr_ack_ptr = av->av_buf_head;
+ avr->avr_ack_ackno = av->av_buf_ackno;
+ avr->avr_ack_nonce = av->av_buf_nonce;
+ avr->avr_sent_len = av->av_vec_len;
dccp_ackvec_insert_avr(av, avr);
dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu\n",
- dccp_role(sk), avr->dccpavr_sent_len,
- (unsigned long long)avr->dccpavr_ack_seqno,
- (unsigned long long)avr->dccpavr_ack_ackno);
+ dccp_role(sk), avr->avr_sent_len,
+ (unsigned long long)avr->avr_ack_seqno,
+ (unsigned long long)avr->avr_ack_ackno);
return 0;
}
@@ -155,12 +153,12 @@ struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
struct dccp_ackvec *av = kmem_cache_alloc(dccp_ackvec_slab, priority);
if (av != NULL) {
- av->dccpav_buf_head = DCCP_MAX_ACKVEC_LEN - 1;
- av->dccpav_buf_ackno = UINT48_MAX + 1;
- av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0;
- av->dccpav_time = ktime_set(0, 0);
- av->dccpav_vec_len = 0;
- INIT_LIST_HEAD(&av->dccpav_records);
+ av->av_buf_head = DCCP_MAX_ACKVEC_LEN - 1;
+ av->av_buf_ackno = UINT48_MAX + 1;
+ av->av_buf_nonce = 0;
+ av->av_time = ktime_set(0, 0);
+ av->av_vec_len = 0;
+ INIT_LIST_HEAD(&av->av_records);
}
return av;
@@ -171,12 +169,11 @@ void dccp_ackvec_free(struct dccp_ackvec *av)
if (unlikely(av == NULL))
return;
- if (!list_empty(&av->dccpav_records)) {
+ if (!list_empty(&av->av_records)) {
struct dccp_ackvec_record *avr, *next;
- list_for_each_entry_safe(avr, next, &av->dccpav_records,
- dccpavr_node) {
- list_del_init(&avr->dccpavr_node);
+ list_for_each_entry_safe(avr, next, &av->av_records, avr_node) {
+ list_del_init(&avr->avr_node);
dccp_ackvec_record_delete(avr);
}
}
@@ -187,13 +184,13 @@ void dccp_ackvec_free(struct dccp_ackvec *av)
static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av,
const u32 index)
{
- return av->dccpav_buf[index] & DCCP_ACKVEC_STATE_MASK;
+ return av->av_buf[index] & DCCP_ACKVEC_STATE_MASK;
}
static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av,
const u32 index)
{
- return av->dccpav_buf[index] & DCCP_ACKVEC_LEN_MASK;
+ return av->av_buf[index] & DCCP_ACKVEC_LEN_MASK;
}
/*
@@ -208,29 +205,29 @@ static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
unsigned int gap;
long new_head;
- if (av->dccpav_vec_len + packets > DCCP_MAX_ACKVEC_LEN)
+ if (av->av_vec_len + packets > DCCP_MAX_ACKVEC_LEN)
return -ENOBUFS;
gap = packets - 1;
- new_head = av->dccpav_buf_head - packets;
+ new_head = av->av_buf_head - packets;
if (new_head < 0) {
if (gap > 0) {
- memset(av->dccpav_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
+ memset(av->av_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
gap + new_head + 1);
gap = -new_head;
}
new_head += DCCP_MAX_ACKVEC_LEN;
}
- av->dccpav_buf_head = new_head;
+ av->av_buf_head = new_head;
if (gap > 0)
- memset(av->dccpav_buf + av->dccpav_buf_head + 1,
+ memset(av->av_buf + av->av_buf_head + 1,
DCCP_ACKVEC_STATE_NOT_RECEIVED, gap);
- av->dccpav_buf[av->dccpav_buf_head] = state;
- av->dccpav_vec_len += packets;
+ av->av_buf[av->av_buf_head] = state;
+ av->av_vec_len += packets;
return 0;
}
@@ -243,7 +240,7 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
/*
* Check at the right places if the buffer is full, if it is, tell the
* caller to start dropping packets till the HC-Sender acks our ACK
- * vectors, when we will free up space in dccpav_buf.
+ * vectors, when we will free up space in av_buf.
*
* We may well decide to do buffer compression, etc, but for now lets
* just drop.
@@ -263,22 +260,20 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
*/
/* See if this is the first ackno being inserted */
- if (av->dccpav_vec_len == 0) {
- av->dccpav_buf[av->dccpav_buf_head] = state;
- av->dccpav_vec_len = 1;
- } else if (after48(ackno, av->dccpav_buf_ackno)) {
- const u64 delta = dccp_delta_seqno(av->dccpav_buf_ackno,
- ackno);
+ if (av->av_vec_len == 0) {
+ av->av_buf[av->av_buf_head] = state;
+ av->av_vec_len = 1;
+ } else if (after48(ackno, av->av_buf_ackno)) {
+ const u64 delta = dccp_delta_seqno(av->av_buf_ackno, ackno);
/*
* Look if the state of this packet is the same as the
* previous ackno and if so if we can bump the head len.
*/
if (delta == 1 &&
- dccp_ackvec_state(av, av->dccpav_buf_head) == state &&
- (dccp_ackvec_len(av, av->dccpav_buf_head) <
- DCCP_ACKVEC_LEN_MASK))
- av->dccpav_buf[av->dccpav_buf_head]++;
+ dccp_ackvec_state(av, av->av_buf_head) == state &&
+ dccp_ackvec_len(av, av->av_buf_head) < DCCP_ACKVEC_LEN_MASK)
+ av->av_buf[av->av_buf_head]++;
else if (dccp_ackvec_set_buf_head_state(av, delta, state))
return -ENOBUFS;
} else {
@@ -290,14 +285,14 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
* the byte corresponding to S. (Indexing structures
* could reduce the complexity of this scan.)
*/
- u64 delta = dccp_delta_seqno(ackno, av->dccpav_buf_ackno);
- u32 index = av->dccpav_buf_head;
+ u64 delta = dccp_delta_seqno(ackno, av->av_buf_ackno);
+ u32 index = av->av_buf_head;
while (1) {
const u8 len = dccp_ackvec_len(av, index);
const u8 state = dccp_ackvec_state(av, index);
/*
- * valid packets not yet in dccpav_buf have a reserved
+ * valid packets not yet in av_buf have a reserved
* entry, with a len equal to 0.
*/
if (state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
@@ -305,7 +300,7 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
reserved seat! */
dccp_pr_debug("Found %llu reserved seat!\n",
(unsigned long long)ackno);
- av->dccpav_buf[index] = state;
+ av->av_buf[index] = state;
goto out;
}
/* len == 0 means one packet */
@@ -318,8 +313,8 @@ int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
}
}
- av->dccpav_buf_ackno = ackno;
- av->dccpav_time = ktime_get_real();
+ av->av_buf_ackno = ackno;
+ av->av_time = ktime_get_real();
out:
return 0;
@@ -349,9 +344,9 @@ void dccp_ackvector_print(const u64 ackno, const unsigned char *vector, int len)
void dccp_ackvec_print(const struct dccp_ackvec *av)
{
- dccp_ackvector_print(av->dccpav_buf_ackno,
- av->dccpav_buf + av->dccpav_buf_head,
- av->dccpav_vec_len);
+ dccp_ackvector_print(av->av_buf_ackno,
+ av->av_buf + av->av_buf_head,
+ av->av_vec_len);
}
#endif
@@ -361,17 +356,15 @@ static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
struct dccp_ackvec_record *next;
/* sort out vector length */
- if (av->dccpav_buf_head <= avr->dccpavr_ack_ptr)
- av->dccpav_vec_len = avr->dccpavr_ack_ptr - av->dccpav_buf_head;
+ if (av->av_buf_head <= avr->avr_ack_ptr)
+ av->av_vec_len = avr->avr_ack_ptr - av->av_buf_head;
else
- av->dccpav_vec_len = DCCP_MAX_ACKVEC_LEN - 1
- - av->dccpav_buf_head
- + avr->dccpavr_ack_ptr;
+ av->av_vec_len = DCCP_MAX_ACKVEC_LEN - 1 -
+ av->av_buf_head + avr->avr_ack_ptr;
/* free records */
- list_for_each_entry_safe_from(avr, next, &av->dccpav_records,
- dccpavr_node) {
- list_del_init(&avr->dccpavr_node);
+ list_for_each_entry_safe_from(avr, next, &av->av_records, avr_node) {
+ list_del_init(&avr->avr_node);
dccp_ackvec_record_delete(avr);
}
}
@@ -386,16 +379,16 @@ void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
* windows. We will be receiving ACKs for stuff we sent a while back
* -sorbo.
*/
- list_for_each_entry_reverse(avr, &av->dccpav_records, dccpavr_node) {
- if (ackno == avr->dccpavr_ack_seqno) {
+ list_for_each_entry_reverse(avr, &av->av_records, avr_node) {
+ if (ackno == avr->avr_ack_seqno) {
dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, "
"ack_ackno=%llu, ACKED!\n",
dccp_role(sk), 1,
- (unsigned long long)avr->dccpavr_ack_seqno,
- (unsigned long long)avr->dccpavr_ack_ackno);
+ (unsigned long long)avr->avr_ack_seqno,
+ (unsigned long long)avr->avr_ack_ackno);
dccp_ackvec_throw_record(av, avr);
break;
- } else if (avr->dccpavr_ack_seqno > ackno)
+ } else if (avr->avr_ack_seqno > ackno)
break; /* old news */
}
}
@@ -409,7 +402,7 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
struct dccp_ackvec_record *avr;
/* Check if we actually sent an ACK vector */
- if (list_empty(&av->dccpav_records))
+ if (list_empty(&av->av_records))
return;
i = len;
@@ -418,8 +411,7 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
* I think it might be more efficient to work backwards. See comment on
* rcv_ackno. -sorbo.
*/
- avr = list_entry(av->dccpav_records.next, struct dccp_ackvec_record,
- dccpavr_node);
+ avr = list_entry(av->av_records.next, struct dccp_ackvec_record, avr_node);
while (i--) {
const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
u64 ackno_end_rl;
@@ -430,15 +422,14 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
* If our AVR sequence number is greater than the ack, go
* forward in the AVR list until it is not so.
*/
- list_for_each_entry_from(avr, &av->dccpav_records,
- dccpavr_node) {
- if (!after48(avr->dccpavr_ack_seqno, *ackno))
+ list_for_each_entry_from(avr, &av->av_records, avr_node) {
+ if (!after48(avr->avr_ack_seqno, *ackno))
goto found;
}
- /* End of the dccpav_records list, not found, exit */
+ /* End of the av_records list, not found, exit */
break;
found:
- if (between48(avr->dccpavr_ack_seqno, ackno_end_rl, *ackno)) {
+ if (between48(avr->avr_ack_seqno, ackno_end_rl, *ackno)) {
const u8 state = *vector & DCCP_ACKVEC_STATE_MASK;
if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
dccp_pr_debug("%s ACK vector 0, len=%d, "
@@ -446,9 +437,9 @@ found:
"ACKED!\n",
dccp_role(sk), len,
(unsigned long long)
- avr->dccpavr_ack_seqno,
+ avr->avr_ack_seqno,
(unsigned long long)
- avr->dccpavr_ack_ackno);
+ avr->avr_ack_ackno);
dccp_ackvec_throw_record(av, avr);
break;
}
diff --git a/net/dccp/ackvec.h b/net/dccp/ackvec.h
index 9671ecd..bcb64fb 100644
--- a/net/dccp/ackvec.h
+++ b/net/dccp/ackvec.h
@@ -32,54 +32,54 @@
*
* This data structure is the one defined in RFC 4340, Appendix A.
*
- * @dccpav_buf_head - circular buffer head
- * @dccpav_buf_tail - circular buffer tail
- * @dccpav_buf_ackno - ack # of the most recent packet acknowledgeable in the
- * buffer (i.e. %dccpav_buf_head)
- * @dccpav_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
+ * @av_buf_head - circular buffer head
+ * @av_buf_tail - circular buffer tail
+ * @av_buf_ackno - ack # of the most recent packet acknowledgeable in the
+ * buffer (i.e. %av_buf_head)
+ * @av_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
* by the buffer with State 0
*
* Additionally, the HC-Receiver must keep some information about the
* Ack Vectors it has recently sent. For each packet sent carrying an
* Ack Vector, it remembers four variables:
*
- * @dccpav_records - list of dccp_ackvec_record
- * @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
+ * @av_records - list of dccp_ackvec_record
+ * @av_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
*
- * @dccpav_time - the time in usecs
- * @dccpav_buf - circular buffer of acknowledgeable packets
+ * @av_time - the time in usecs
+ * @av_buf - circular buffer of acknowledgeable packets
*/
struct dccp_ackvec {
- u64 dccpav_buf_ackno;
- struct list_head dccpav_records;
- ktime_t dccpav_time;
- u16 dccpav_buf_head;
- u16 dccpav_vec_len;
- u8 dccpav_buf_nonce;
- u8 dccpav_ack_nonce;
- u8 dccpav_buf[DCCP_MAX_ACKVEC_LEN];
+ u64 av_buf_ackno;
+ struct list_head av_records;
+ ktime_t av_time;
+ u16 av_buf_head;
+ u16 av_vec_len;
+ u8 av_buf_nonce;
+ u8 av_ack_nonce;
+ u8 av_buf[DCCP_MAX_ACKVEC_LEN];
};
/** struct dccp_ackvec_record - ack vector record
*
* ACK vector record as defined in Appendix A of spec.
*
- * The list is sorted by dccpavr_ack_seqno
+ * The list is sorted by avr_ack_seqno
*
- * @dccpavr_node - node in dccpav_records
- * @dccpavr_ack_seqno - sequence number of the packet this record was sent on
- * @dccpavr_ack_ackno - sequence number being acknowledged
- * @dccpavr_ack_ptr - pointer into dccpav_buf where this record starts
- * @dccpavr_ack_nonce - dccpav_ack_nonce at the time this record was sent
- * @dccpavr_sent_len - length of the record in dccpav_buf
+ * @avr_node - node in av_records
+ * @avr_ack_seqno - sequence number of the packet this record was sent on
+ * @avr_ack_ackno - sequence number being acknowledged
+ * @avr_ack_ptr - pointer into av_buf where this record starts
+ * @avr_ack_nonce - av_ack_nonce at the time this record was sent
+ * @avr_sent_len - lenght of the record in av_buf
*/
struct dccp_ackvec_record {
- struct list_head dccpavr_node;
- u64 dccpavr_ack_seqno;
- u64 dccpavr_ack_ackno;
- u16 dccpavr_ack_ptr;
- u16 dccpavr_sent_len;
- u8 dccpavr_ack_nonce;
+ struct list_head avr_node;
+ u64 avr_ack_seqno;
+ u64 avr_ack_ackno;
+ u16 avr_ack_ptr;
+ u16 avr_sent_len;
+ u8 avr_ack_nonce;
};
struct sock;
@@ -105,7 +105,7 @@ extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
{
- return av->dccpav_vec_len;
+ return av->av_vec_len;
}
#else /* CONFIG_IP_DCCP_ACKVEC */
static inline int dccp_ackvec_init(void)
diff --git a/net/dccp/ccid.c b/net/dccp/ccid.c
index c45088b..4809753d1 100644
--- a/net/dccp/ccid.c
+++ b/net/dccp/ccid.c
@@ -92,15 +92,15 @@ int ccid_register(struct ccid_operations *ccid_ops)
ccid_ops->ccid_hc_rx_slab =
ccid_kmem_cache_create(ccid_ops->ccid_hc_rx_obj_size,
- "%s_hc_rx_sock",
- ccid_ops->ccid_name);
+ "ccid%u_hc_rx_sock",
+ ccid_ops->ccid_id);
if (ccid_ops->ccid_hc_rx_slab == NULL)
goto out;
ccid_ops->ccid_hc_tx_slab =
ccid_kmem_cache_create(ccid_ops->ccid_hc_tx_obj_size,
- "%s_hc_tx_sock",
- ccid_ops->ccid_name);
+ "ccid%u_hc_tx_sock",
+ ccid_ops->ccid_id);
if (ccid_ops->ccid_hc_tx_slab == NULL)
goto out_free_rx_slab;
diff --git a/net/dccp/ccid.h b/net/dccp/ccid.h
index c65cb24..fdeae7b 100644
--- a/net/dccp/ccid.h
+++ b/net/dccp/ccid.h
@@ -23,14 +23,37 @@
struct tcp_info;
+/**
+ * struct ccid_operations - Interface to Congestion-Control Infrastructure
+ *
+ * @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.)
+ * @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled)
+ * @ccid_name: alphabetical identifier string for @ccid_id
+ * @ccid_owner: module which implements/owns this CCID
+ * @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection
+ * @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket
+ *
+ * @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup)
+ * @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction)
+ * @ccid_hc_rx_packet_recv: implements the HC-receiver side
+ * @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options
+ * @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options
+ * @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender
+ * @ccid_hc_tx_send_packet: implements the sending part of the HC-sender
+ * @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender
+ * @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender
+ * @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender
+ */
struct ccid_operations {
- unsigned char ccid_id;
- const char *ccid_name;
- struct module *ccid_owner;
- struct kmem_cache *ccid_hc_rx_slab;
- __u32 ccid_hc_rx_obj_size;
- struct kmem_cache *ccid_hc_tx_slab;
- __u32 ccid_hc_tx_obj_size;
+ unsigned char ccid_id;
+ __u32 ccid_ccmps;
+ const char *ccid_name;
+ struct module *ccid_owner;
+ struct kmem_cache *ccid_hc_rx_slab,
+ *ccid_hc_tx_slab;
+ __u32 ccid_hc_rx_obj_size,
+ ccid_hc_tx_obj_size;
+ /* Interface Routines */
int (*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk);
int (*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk);
void (*ccid_hc_rx_exit)(struct sock *sk);
diff --git a/net/dccp/ccids/Kconfig b/net/dccp/ccids/Kconfig
index 80f4698..1227594 100644
--- a/net/dccp/ccids/Kconfig
+++ b/net/dccp/ccids/Kconfig
@@ -1,9 +1,8 @@
menu "DCCP CCIDs Configuration (EXPERIMENTAL)"
- depends on IP_DCCP && EXPERIMENTAL
+ depends on EXPERIMENTAL
config IP_DCCP_CCID2
tristate "CCID2 (TCP-Like) (EXPERIMENTAL)"
- depends on IP_DCCP
def_tristate IP_DCCP
select IP_DCCP_ACKVEC
---help---
@@ -20,18 +19,9 @@ config IP_DCCP_CCID2
to the user. For example, a hypothetical application that
transferred files over DCCP, using application-level retransmissions
for lost packets, would prefer CCID 2 to CCID 3. On-line games may
- also prefer CCID 2.
+ also prefer CCID 2. See RFC 4341 for further details.
- CCID 2 is further described in RFC 4341,
- http://www.ietf.org/rfc/rfc4341.txt
-
- This text was extracted from RFC 4340 (sec. 10.1),
- http://www.ietf.org/rfc/rfc4340.txt
-
- To compile this CCID as a module, choose M here: the module will be
- called dccp_ccid2.
-
- If in doubt, say M.
+ CCID2 is the default CCID used by DCCP.
config IP_DCCP_CCID2_DEBUG
bool "CCID2 debugging messages"
@@ -47,8 +37,8 @@ config IP_DCCP_CCID2_DEBUG
config IP_DCCP_CCID3
tristate "CCID3 (TCP-Friendly) (EXPERIMENTAL)"
- depends on IP_DCCP
def_tristate IP_DCCP
+ select IP_DCCP_TFRC_LIB
---help---
CCID 3 denotes TCP-Friendly Rate Control (TFRC), an equation-based
rate-controlled congestion control mechanism. TFRC is designed to
@@ -74,10 +64,6 @@ config IP_DCCP_CCID3
If in doubt, say M.
-config IP_DCCP_TFRC_LIB
- depends on IP_DCCP_CCID3
- def_tristate IP_DCCP_CCID3
-
config IP_DCCP_CCID3_DEBUG
bool "CCID3 debugging messages"
depends on IP_DCCP_CCID3
@@ -121,5 +107,13 @@ config IP_DCCP_CCID3_RTO
is serious network congestion: experimenting with larger values should
therefore not be performed on WANs.
+config IP_DCCP_TFRC_LIB
+ tristate
+ default n
+
+config IP_DCCP_TFRC_DEBUG
+ bool
+ depends on IP_DCCP_TFRC_LIB
+ default y if IP_DCCP_CCID3_DEBUG
endmenu
diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c
index d694656..b5b52eb 100644
--- a/net/dccp/ccids/ccid2.c
+++ b/net/dccp/ccids/ccid2.c
@@ -24,9 +24,6 @@
/*
* This implementation should follow RFC 4341
- *
- * BUGS:
- * - sequence number wrapping
*/
#include "../ccid.h"
@@ -129,50 +126,35 @@ static int ccid2_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- ccid2_pr_debug("pipe=%d cwnd=%d\n", hctx->ccid2hctx_pipe,
- hctx->ccid2hctx_cwnd);
-
- if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd) {
- /* OK we can send... make sure previous packet was sent off */
- if (!hctx->ccid2hctx_sendwait) {
- hctx->ccid2hctx_sendwait = 1;
- return 0;
- }
- }
+ if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd)
+ return 0;
return 1; /* XXX CCID should dequeue when ready instead of polling */
}
-static void ccid2_change_l_ack_ratio(struct sock *sk, int val)
+static void ccid2_change_l_ack_ratio(struct sock *sk, u32 val)
{
struct dccp_sock *dp = dccp_sk(sk);
+ u32 max_ratio = DIV_ROUND_UP(ccid2_hc_tx_sk(sk)->ccid2hctx_cwnd, 2);
+
/*
- * XXX I don't really agree with val != 2. If cwnd is 1, ack ratio
- * should be 1... it shouldn't be allowed to become 2.
- * -sorbo.
+ * Ensure that Ack Ratio does not exceed ceil(cwnd/2), which is (2) from
+ * RFC 4341, 6.1.2. We ignore the statement that Ack Ratio 2 is always
+ * acceptable since this causes starvation/deadlock whenever cwnd < 2.
+ * The same problem arises when Ack Ratio is 0 (ie. Ack Ratio disabled).
*/
- if (val != 2) {
- const struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- int max = hctx->ccid2hctx_cwnd / 2;
-
- /* round up */
- if (hctx->ccid2hctx_cwnd & 1)
- max++;
-
- if (val > max)
- val = max;
+ if (val == 0 || val > max_ratio) {
+ DCCP_WARN("Limiting Ack Ratio (%u) to %u\n", val, max_ratio);
+ val = max_ratio;
}
+ if (val > 0xFFFF) /* RFC 4340, 11.3 */
+ val = 0xFFFF;
- ccid2_pr_debug("changing local ack ratio to %d\n", val);
- WARN_ON(val <= 0);
- dp->dccps_l_ack_ratio = val;
-}
+ if (val == dp->dccps_l_ack_ratio)
+ return;
-static void ccid2_change_cwnd(struct ccid2_hc_tx_sock *hctx, u32 val)
-{
- /* XXX do we need to change ack ratio? */
- hctx->ccid2hctx_cwnd = val? : 1;
- ccid2_pr_debug("changed cwnd to %u\n", hctx->ccid2hctx_cwnd);
+ ccid2_pr_debug("changing local ack ratio to %u\n", val);
+ dp->dccps_l_ack_ratio = val;
}
static void ccid2_change_srtt(struct ccid2_hc_tx_sock *hctx, long val)
@@ -181,11 +163,6 @@ static void ccid2_change_srtt(struct ccid2_hc_tx_sock *hctx, long val)
hctx->ccid2hctx_srtt = val;
}
-static void ccid2_change_pipe(struct ccid2_hc_tx_sock *hctx, long val)
-{
- hctx->ccid2hctx_pipe = val;
-}
-
static void ccid2_start_rto_timer(struct sock *sk);
static void ccid2_hc_tx_rto_expire(unsigned long data)
@@ -215,21 +192,17 @@ static void ccid2_hc_tx_rto_expire(unsigned long data)
ccid2_start_rto_timer(sk);
/* adjust pipe, cwnd etc */
- ccid2_change_pipe(hctx, 0);
- hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd >> 1;
+ hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd / 2;
if (hctx->ccid2hctx_ssthresh < 2)
hctx->ccid2hctx_ssthresh = 2;
- ccid2_change_cwnd(hctx, 1);
+ hctx->ccid2hctx_cwnd = 1;
+ hctx->ccid2hctx_pipe = 0;
/* clear state about stuff we sent */
- hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
- hctx->ccid2hctx_ssacks = 0;
- hctx->ccid2hctx_acks = 0;
- hctx->ccid2hctx_sent = 0;
+ hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
+ hctx->ccid2hctx_packets_acked = 0;
/* clear ack ratio state. */
- hctx->ccid2hctx_arsent = 0;
- hctx->ccid2hctx_ackloss = 0;
hctx->ccid2hctx_rpseq = 0;
hctx->ccid2hctx_rpdupack = -1;
ccid2_change_l_ack_ratio(sk, 1);
@@ -255,23 +228,10 @@ static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
struct dccp_sock *dp = dccp_sk(sk);
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
struct ccid2_seq *next;
- u64 seq;
-
- ccid2_hc_tx_check_sanity(hctx);
- BUG_ON(!hctx->ccid2hctx_sendwait);
- hctx->ccid2hctx_sendwait = 0;
- ccid2_change_pipe(hctx, hctx->ccid2hctx_pipe + 1);
- BUG_ON(hctx->ccid2hctx_pipe < 0);
+ hctx->ccid2hctx_pipe++;
- /* There is an issue. What if another packet is sent between
- * packet_send() and packet_sent(). Then the sequence number would be
- * wrong.
- * -sorbo.
- */
- seq = dp->dccps_gss;
-
- hctx->ccid2hctx_seqh->ccid2s_seq = seq;
+ hctx->ccid2hctx_seqh->ccid2s_seq = dp->dccps_gss;
hctx->ccid2hctx_seqh->ccid2s_acked = 0;
hctx->ccid2hctx_seqh->ccid2s_sent = jiffies;
@@ -291,8 +251,26 @@ static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->ccid2hctx_cwnd,
hctx->ccid2hctx_pipe);
- hctx->ccid2hctx_sent++;
-
+ /*
+ * FIXME: The code below is broken and the variables have been removed
+ * from the socket struct. The `ackloss' variable was always set to 0,
+ * and with arsent there are several problems:
+ * (i) it doesn't just count the number of Acks, but all sent packets;
+ * (ii) it is expressed in # of packets, not # of windows, so the
+ * comparison below uses the wrong formula: Appendix A of RFC 4341
+ * comes up with the number K = cwnd / (R^2 - R) of consecutive windows
+ * of data with no lost or marked Ack packets. If arsent were the # of
+ * consecutive Acks received without loss, then Ack Ratio needs to be
+ * decreased by 1 when
+ * arsent >= K * cwnd / R = cwnd^2 / (R^3 - R^2)
+ * where cwnd / R is the number of Acks received per window of data
+ * (cf. RFC 4341, App. A). The problems are that
+ * - arsent counts other packets as well;
+ * - the comparison uses a formula different from RFC 4341;
+ * - computing a cubic/quadratic equation each time is too complicated.
+ * Hence a different algorithm is needed.
+ */
+#if 0
/* Ack Ratio. Need to maintain a concept of how many windows we sent */
hctx->ccid2hctx_arsent++;
/* We had an ack loss in this window... */
@@ -320,14 +298,13 @@ static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
hctx->ccid2hctx_arsent = 0; /* or maybe set it to cwnd*/
}
}
+#endif
/* setup RTO timer */
if (!timer_pending(&hctx->ccid2hctx_rtotimer))
ccid2_start_rto_timer(sk);
#ifdef CONFIG_IP_DCCP_CCID2_DEBUG
- ccid2_pr_debug("pipe=%d\n", hctx->ccid2hctx_pipe);
- ccid2_pr_debug("Sent: seq=%llu\n", (unsigned long long)seq);
do {
struct ccid2_seq *seqp = hctx->ccid2hctx_seqt;
@@ -419,31 +396,15 @@ static inline void ccid2_new_ack(struct sock *sk,
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- /* slow start */
if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh) {
- hctx->ccid2hctx_acks = 0;
-
- /* We can increase cwnd at most maxincr [ack_ratio/2] */
- if (*maxincr) {
- /* increase every 2 acks */
- hctx->ccid2hctx_ssacks++;
- if (hctx->ccid2hctx_ssacks == 2) {
- ccid2_change_cwnd(hctx, hctx->ccid2hctx_cwnd+1);
- hctx->ccid2hctx_ssacks = 0;
- *maxincr = *maxincr - 1;
- }
- } else {
- /* increased cwnd enough for this single ack */
- hctx->ccid2hctx_ssacks = 0;
- }
- } else {
- hctx->ccid2hctx_ssacks = 0;
- hctx->ccid2hctx_acks++;
-
- if (hctx->ccid2hctx_acks >= hctx->ccid2hctx_cwnd) {
- ccid2_change_cwnd(hctx, hctx->ccid2hctx_cwnd + 1);
- hctx->ccid2hctx_acks = 0;
+ if (*maxincr > 0 && ++hctx->ccid2hctx_packets_acked == 2) {
+ hctx->ccid2hctx_cwnd += 1;
+ *maxincr -= 1;
+ hctx->ccid2hctx_packets_acked = 0;
}
+ } else if (++hctx->ccid2hctx_packets_acked >= hctx->ccid2hctx_cwnd) {
+ hctx->ccid2hctx_cwnd += 1;
+ hctx->ccid2hctx_packets_acked = 0;
}
/* update RTO */
@@ -502,7 +463,6 @@ static inline void ccid2_new_ack(struct sock *sk,
ccid2_pr_debug("srtt: %ld rttvar: %ld rto: %ld (HZ=%d) R=%lu\n",
hctx->ccid2hctx_srtt, hctx->ccid2hctx_rttvar,
hctx->ccid2hctx_rto, HZ, r);
- hctx->ccid2hctx_sent = 0;
}
/* we got a new ack, so re-start RTO timer */
@@ -514,16 +474,19 @@ static void ccid2_hc_tx_dec_pipe(struct sock *sk)
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- ccid2_change_pipe(hctx, hctx->ccid2hctx_pipe-1);
- BUG_ON(hctx->ccid2hctx_pipe < 0);
+ if (hctx->ccid2hctx_pipe == 0)
+ DCCP_BUG("pipe == 0");
+ else
+ hctx->ccid2hctx_pipe--;
if (hctx->ccid2hctx_pipe == 0)
ccid2_hc_tx_kill_rto_timer(sk);
}
-static void ccid2_congestion_event(struct ccid2_hc_tx_sock *hctx,
- struct ccid2_seq *seqp)
+static void ccid2_congestion_event(struct sock *sk, struct ccid2_seq *seqp)
{
+ struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
+
if (time_before(seqp->ccid2s_sent, hctx->ccid2hctx_last_cong)) {
ccid2_pr_debug("Multiple losses in an RTT---treating as one\n");
return;
@@ -531,10 +494,12 @@ static void ccid2_congestion_event(struct ccid2_hc_tx_sock *hctx,
hctx->ccid2hctx_last_cong = jiffies;
- ccid2_change_cwnd(hctx, hctx->ccid2hctx_cwnd >> 1);
- hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd;
- if (hctx->ccid2hctx_ssthresh < 2)
- hctx->ccid2hctx_ssthresh = 2;
+ hctx->ccid2hctx_cwnd = hctx->ccid2hctx_cwnd / 2 ? : 1U;
+ hctx->ccid2hctx_ssthresh = max(hctx->ccid2hctx_cwnd, 2U);
+
+ /* Avoid spurious timeouts resulting from Ack Ratio > cwnd */
+ if (dccp_sk(sk)->dccps_l_ack_ratio > hctx->ccid2hctx_cwnd)
+ ccid2_change_l_ack_ratio(sk, hctx->ccid2hctx_cwnd);
}
static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
@@ -570,12 +535,11 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
hctx->ccid2hctx_rpdupack++;
/* check if we got enough dupacks */
- if (hctx->ccid2hctx_rpdupack >=
- hctx->ccid2hctx_numdupack) {
+ if (hctx->ccid2hctx_rpdupack >= NUMDUPACK) {
hctx->ccid2hctx_rpdupack = -1; /* XXX lame */
hctx->ccid2hctx_rpseq = 0;
- ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio << 1);
+ ccid2_change_l_ack_ratio(sk, 2 * dp->dccps_l_ack_ratio);
}
}
}
@@ -606,12 +570,13 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
}
}
- /* If in slow-start, cwnd can increase at most Ack Ratio / 2 packets for
- * this single ack. I round up.
- * -sorbo.
+ /*
+ * In slow-start, cwnd can increase up to a maximum of Ack Ratio/2
+ * packets per acknowledgement. Rounding up avoids that cwnd is not
+ * advanced when Ack Ratio is 1 and gives a slight edge otherwise.
*/
- maxincr = dp->dccps_l_ack_ratio >> 1;
- maxincr++;
+ if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh)
+ maxincr = DIV_ROUND_UP(dp->dccps_l_ack_ratio, 2);
/* go through all ack vectors */
while ((offset = ccid2_ackvector(sk, skb, offset,
@@ -619,9 +584,8 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
/* go through this ack vector */
while (veclen--) {
const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
- u64 ackno_end_rl;
+ u64 ackno_end_rl = SUB48(ackno, rl);
- dccp_set_seqno(&ackno_end_rl, ackno - rl);
ccid2_pr_debug("ackvec start:%llu end:%llu\n",
(unsigned long long)ackno,
(unsigned long long)ackno_end_rl);
@@ -651,7 +615,7 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
!seqp->ccid2s_acked) {
if (state ==
DCCP_ACKVEC_STATE_ECN_MARKED) {
- ccid2_congestion_event(hctx,
+ ccid2_congestion_event(sk,
seqp);
} else
ccid2_new_ack(sk, seqp,
@@ -666,13 +630,12 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
done = 1;
break;
}
- seqp = seqp->ccid2s_next;
+ seqp = seqp->ccid2s_prev;
}
if (done)
break;
-
- dccp_set_seqno(&ackno, ackno_end_rl - 1);
+ ackno = SUB48(ackno_end_rl, 1);
vector++;
}
if (done)
@@ -694,7 +657,7 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
while (1) {
if (seqp->ccid2s_acked) {
done++;
- if (done == hctx->ccid2hctx_numdupack)
+ if (done == NUMDUPACK)
break;
}
if (seqp == hctx->ccid2hctx_seqt)
@@ -705,7 +668,7 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
/* If there are at least 3 acknowledgements, anything unacknowledged
* below the last sequence number is considered lost
*/
- if (done == hctx->ccid2hctx_numdupack) {
+ if (done == NUMDUPACK) {
struct ccid2_seq *last_acked = seqp;
/* check for lost packets */
@@ -717,7 +680,7 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
* order to detect multiple congestion events in
* one ack vector.
*/
- ccid2_congestion_event(hctx, seqp);
+ ccid2_congestion_event(sk, seqp);
ccid2_hc_tx_dec_pipe(sk);
}
if (seqp == hctx->ccid2hctx_seqt)
@@ -742,14 +705,23 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk)
{
struct ccid2_hc_tx_sock *hctx = ccid_priv(ccid);
+ struct dccp_sock *dp = dccp_sk(sk);
+ u32 max_ratio;
+
+ /* RFC 4341, 5: initialise ssthresh to arbitrarily high (max) value */
+ hctx->ccid2hctx_ssthresh = ~0U;
- ccid2_change_cwnd(hctx, 1);
- /* Initialize ssthresh to infinity. This means that we will exit the
- * initial slow-start after the first packet loss. This is what we
- * want.
+ /*
+ * RFC 4341, 5: "The cwnd parameter is initialized to at most four
+ * packets for new connections, following the rules from [RFC3390]".
+ * We need to convert the bytes of RFC3390 into the packets of RFC 4341.
*/
- hctx->ccid2hctx_ssthresh = ~0;
- hctx->ccid2hctx_numdupack = 3;
+ hctx->ccid2hctx_cwnd = min(4U, max(2U, 4380U / dp->dccps_mss_cache));
+
+ /* Make sure that Ack Ratio is enabled and within bounds. */
+ max_ratio = DIV_ROUND_UP(hctx->ccid2hctx_cwnd, 2);
+ if (dp->dccps_l_ack_ratio == 0 || dp->dccps_l_ack_ratio > max_ratio)
+ dp->dccps_l_ack_ratio = max_ratio;
/* XXX init ~ to window size... */
if (ccid2_hc_tx_alloc_seq(hctx))
@@ -760,10 +732,8 @@ static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk)
hctx->ccid2hctx_rttvar = -1;
hctx->ccid2hctx_rpdupack = -1;
hctx->ccid2hctx_last_cong = jiffies;
-
- hctx->ccid2hctx_rtotimer.function = &ccid2_hc_tx_rto_expire;
- hctx->ccid2hctx_rtotimer.data = (unsigned long)sk;
- init_timer(&hctx->ccid2hctx_rtotimer);
+ setup_timer(&hctx->ccid2hctx_rtotimer, ccid2_hc_tx_rto_expire,
+ (unsigned long)sk);
ccid2_hc_tx_check_sanity(hctx);
return 0;
@@ -800,7 +770,7 @@ static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
static struct ccid_operations ccid2 = {
.ccid_id = DCCPC_CCID2,
- .ccid_name = "ccid2",
+ .ccid_name = "TCP-like",
.ccid_owner = THIS_MODULE,
.ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock),
.ccid_hc_tx_init = ccid2_hc_tx_init,
diff --git a/net/dccp/ccids/ccid2.h b/net/dccp/ccids/ccid2.h
index d9daa53..2c94ca0 100644
--- a/net/dccp/ccids/ccid2.h
+++ b/net/dccp/ccids/ccid2.h
@@ -24,6 +24,8 @@
#include <linux/timer.h>
#include <linux/types.h>
#include "../ccid.h"
+/* NUMDUPACK parameter from RFC 4341, p. 6 */
+#define NUMDUPACK 3
struct sock;
@@ -40,22 +42,17 @@ struct ccid2_seq {
/** struct ccid2_hc_tx_sock - CCID2 TX half connection
*
- * @ccid2hctx_ssacks - ACKs recv in slow start
- * @ccid2hctx_acks - ACKS recv in AI phase
- * @ccid2hctx_sent - packets sent in this window
+ * @ccid2hctx_{cwnd,ssthresh,pipe}: as per RFC 4341, section 5
+ * @ccid2hctx_packets_acked - Ack counter for deriving cwnd growth (RFC 3465)
* @ccid2hctx_lastrtt -time RTT was last measured
- * @ccid2hctx_arsent - packets sent [ack ratio]
- * @ccid2hctx_ackloss - ack was lost in this win
* @ccid2hctx_rpseq - last consecutive seqno
* @ccid2hctx_rpdupack - dupacks since rpseq
*/
struct ccid2_hc_tx_sock {
u32 ccid2hctx_cwnd;
- int ccid2hctx_ssacks;
- int ccid2hctx_acks;
- unsigned int ccid2hctx_ssthresh;
- int ccid2hctx_pipe;
- int ccid2hctx_numdupack;
+ u32 ccid2hctx_ssthresh;
+ u32 ccid2hctx_pipe;
+ u32 ccid2hctx_packets_acked;
struct ccid2_seq *ccid2hctx_seqbuf[CCID2_SEQBUF_MAX];
int ccid2hctx_seqbufc;
struct ccid2_seq *ccid2hctx_seqh;
@@ -63,14 +60,10 @@ struct ccid2_hc_tx_sock {
long ccid2hctx_rto;
long ccid2hctx_srtt;
long ccid2hctx_rttvar;
- int ccid2hctx_sent;
unsigned long ccid2hctx_lastrtt;
struct timer_list ccid2hctx_rtotimer;
- unsigned long ccid2hctx_arsent;
- int ccid2hctx_ackloss;
u64 ccid2hctx_rpseq;
int ccid2hctx_rpdupack;
- int ccid2hctx_sendwait;
unsigned long ccid2hctx_last_cong;
u64 ccid2hctx_high_ack;
};
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index d133416..e76f460 100644
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -1,6 +1,7 @@
/*
* net/dccp/ccids/ccid3.c
*
+ * Copyright (c) 2007 The University of Aberdeen, Scotland, UK
* Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand.
* Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz>
*
@@ -33,11 +34,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-#include "../ccid.h"
#include "../dccp.h"
-#include "lib/packet_history.h"
-#include "lib/loss_interval.h"
-#include "lib/tfrc.h"
#include "ccid3.h"
#include <asm/unaligned.h>
@@ -49,9 +46,6 @@ static int ccid3_debug;
#define ccid3_pr_debug(format, a...)
#endif
-static struct dccp_tx_hist *ccid3_tx_hist;
-static struct dccp_rx_hist *ccid3_rx_hist;
-
/*
* Transmitter Half-Connection Routines
*/
@@ -83,24 +77,27 @@ static void ccid3_hc_tx_set_state(struct sock *sk,
}
/*
- * Compute the initial sending rate X_init according to RFC 3390:
- * w_init = min(4 * MSS, max(2 * MSS, 4380 bytes))
- * X_init = w_init / RTT
+ * Compute the initial sending rate X_init in the manner of RFC 3390:
+ *
+ * X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT
+ *
+ * Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis
+ * (rev-02) clarifies the use of RFC 3390 with regard to the above formula.
* For consistency with other parts of the code, X_init is scaled by 2^6.
*/
static inline u64 rfc3390_initial_rate(struct sock *sk)
{
- const struct dccp_sock *dp = dccp_sk(sk);
- const __u32 w_init = min(4 * dp->dccps_mss_cache,
- max(2 * dp->dccps_mss_cache, 4380U));
+ const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
+ const __u32 w_init = min_t(__u32, 4 * hctx->ccid3hctx_s,
+ max_t(__u32, 2 * hctx->ccid3hctx_s, 4380));
- return scaled_div(w_init << 6, ccid3_hc_tx_sk(sk)->ccid3hctx_rtt);
+ return scaled_div(w_init << 6, hctx->ccid3hctx_rtt);
}
/*
* Recalculate t_ipi and delta (should be called whenever X changes)
*/
-static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx)
+static void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx)
{
/* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */
hctx->ccid3hctx_t_ipi = scaled_div32(((u64)hctx->ccid3hctx_s) << 6,
@@ -116,6 +113,13 @@ static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx)
}
+static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hctx, ktime_t now)
+{
+ u32 delta = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count);
+
+ return delta / hctx->ccid3hctx_rtt;
+}
+
/**
* ccid3_hc_tx_update_x - Update allowed sending rate X
* @stamp: most recent time if available - can be left NULL.
@@ -127,19 +131,19 @@ static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx)
*
*/
static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp)
-
{
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
__u64 min_rate = 2 * hctx->ccid3hctx_x_recv;
const __u64 old_x = hctx->ccid3hctx_x;
- ktime_t now = stamp? *stamp : ktime_get_real();
+ ktime_t now = stamp ? *stamp : ktime_get_real();
/*
* Handle IDLE periods: do not reduce below RFC3390 initial sending rate
- * when idling [RFC 4342, 5.1]. See also draft-ietf-dccp-rfc3448bis.
+ * when idling [RFC 4342, 5.1]. Definition of idling is from rfc3448bis:
+ * a sender is idle if it has not sent anything over a 2-RTT-period.
* For consistency with X and X_recv, min_rate is also scaled by 2^6.
*/
- if (unlikely(hctx->ccid3hctx_idle)) {
+ if (ccid3_hc_tx_idle_rtt(hctx, now) >= 2) {
min_rate = rfc3390_initial_rate(sk);
min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv);
}
@@ -181,7 +185,7 @@ static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len)
{
const u16 old_s = hctx->ccid3hctx_s;
- hctx->ccid3hctx_s = old_s == 0 ? len : (9 * old_s + len) / 10;
+ hctx->ccid3hctx_s = tfrc_ewma(hctx->ccid3hctx_s, len, 9);
if (hctx->ccid3hctx_s != old_s)
ccid3_update_send_interval(hctx);
@@ -225,29 +229,27 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk,
ccid3_tx_state_name(hctx->ccid3hctx_state));
- hctx->ccid3hctx_idle = 1;
+ if (hctx->ccid3hctx_state == TFRC_SSTATE_FBACK)
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
+ else if (hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK)
+ goto out;
- switch (hctx->ccid3hctx_state) {
- case TFRC_SSTATE_NO_FBACK:
- /* RFC 3448, 4.4: Halve send rate directly */
+ /*
+ * Determine new allowed sending rate X as per draft rfc3448bis-00, 4.4
+ */
+ if (hctx->ccid3hctx_t_rto == 0 || /* no feedback received yet */
+ hctx->ccid3hctx_p == 0) {
+
+ /* halve send rate directly */
hctx->ccid3hctx_x = max(hctx->ccid3hctx_x / 2,
(((__u64)hctx->ccid3hctx_s) << 6) /
TFRC_T_MBI);
-
- ccid3_pr_debug("%s(%p, state=%s), updated tx rate to %u "
- "bytes/s\n", dccp_role(sk), sk,
- ccid3_tx_state_name(hctx->ccid3hctx_state),
- (unsigned)(hctx->ccid3hctx_x >> 6));
- /* The value of R is still undefined and so we can not recompute
- * the timeout value. Keep initial value as per [RFC 4342, 5]. */
- t_nfb = TFRC_INITIAL_TIMEOUT;
ccid3_update_send_interval(hctx);
- break;
- case TFRC_SSTATE_FBACK:
+ } else {
/*
- * Modify the cached value of X_recv [RFC 3448, 4.4]
+ * Modify the cached value of X_recv
*
- * If (p == 0 || X_calc > 2 * X_recv)
+ * If (X_calc > 2 * X_recv)
* X_recv = max(X_recv / 2, s / (2 * t_mbi));
* Else
* X_recv = X_calc / 4;
@@ -256,32 +258,28 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
*/
BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc);
- if (hctx->ccid3hctx_p == 0 ||
- (hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))) {
-
+ if (hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))
hctx->ccid3hctx_x_recv =
max(hctx->ccid3hctx_x_recv / 2,
(((__u64)hctx->ccid3hctx_s) << 6) /
(2 * TFRC_T_MBI));
- } else {
+ else {
hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc;
hctx->ccid3hctx_x_recv <<= 4;
}
- /* Now recalculate X [RFC 3448, 4.3, step (4)] */
ccid3_hc_tx_update_x(sk, NULL);
- /*
- * Schedule no feedback timer to expire in
- * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi)
- * See comments in packet_recv() regarding the value of t_RTO.
- */
- t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
- break;
- case TFRC_SSTATE_NO_SENT:
- DCCP_BUG("%s(%p) - Illegal state NO_SENT", dccp_role(sk), sk);
- /* fall through */
- case TFRC_SSTATE_TERM:
- goto out;
}
+ ccid3_pr_debug("Reduced X to %llu/64 bytes/sec\n",
+ (unsigned long long)hctx->ccid3hctx_x);
+
+ /*
+ * Set new timeout for the nofeedback timer.
+ * See comments in packet_recv() regarding the value of t_RTO.
+ */
+ if (unlikely(hctx->ccid3hctx_t_rto == 0)) /* no feedback yet */
+ t_nfb = TFRC_INITIAL_TIMEOUT;
+ else
+ t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
restart_timer:
sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
@@ -336,8 +334,8 @@ static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
hctx->ccid3hctx_x = rfc3390_initial_rate(sk);
hctx->ccid3hctx_t_ld = now;
} else {
- /* Sender does not have RTT sample: X = MSS/second */
- hctx->ccid3hctx_x = dp->dccps_mss_cache;
+ /* Sender does not have RTT sample: X_pps = 1 pkt/sec */
+ hctx->ccid3hctx_x = hctx->ccid3hctx_s;
hctx->ccid3hctx_x <<= 6;
}
ccid3_update_send_interval(hctx);
@@ -369,7 +367,6 @@ static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
/* prepare to send now (add options etc.) */
dp->dccps_hc_tx_insert_options = 1;
DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count;
- hctx->ccid3hctx_idle = 0;
/* set the nominal send time for the next following packet */
hctx->ccid3hctx_t_nom = ktime_add_us(hctx->ccid3hctx_t_nom,
@@ -381,28 +378,17 @@ static void ccid3_hc_tx_packet_sent(struct sock *sk, int more,
unsigned int len)
{
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
- struct dccp_tx_hist_entry *packet;
ccid3_hc_tx_update_s(hctx, len);
- packet = dccp_tx_hist_entry_new(ccid3_tx_hist, GFP_ATOMIC);
- if (unlikely(packet == NULL)) {
+ if (tfrc_tx_hist_add(&hctx->ccid3hctx_hist, dccp_sk(sk)->dccps_gss))
DCCP_CRIT("packet history - out of memory!");
- return;
- }
- dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, packet);
-
- packet->dccphtx_tstamp = ktime_get_real();
- packet->dccphtx_seqno = dccp_sk(sk)->dccps_gss;
- packet->dccphtx_rtt = hctx->ccid3hctx_rtt;
- packet->dccphtx_sent = 1;
}
static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
{
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
struct ccid3_options_received *opt_recv;
- struct dccp_tx_hist_entry *packet;
ktime_t now;
unsigned long t_nfb;
u32 pinv, r_sample;
@@ -411,131 +397,112 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK ||
DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK))
return;
+ /* ... and only in the established state */
+ if (hctx->ccid3hctx_state != TFRC_SSTATE_FBACK &&
+ hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK)
+ return;
opt_recv = &hctx->ccid3hctx_options_received;
+ now = ktime_get_real();
- switch (hctx->ccid3hctx_state) {
- case TFRC_SSTATE_NO_FBACK:
- case TFRC_SSTATE_FBACK:
- /* get packet from history to look up t_recvdata */
- packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist,
- DCCP_SKB_CB(skb)->dccpd_ack_seq);
- if (unlikely(packet == NULL)) {
- DCCP_WARN("%s(%p), seqno %llu(%s) doesn't exist "
- "in history!\n", dccp_role(sk), sk,
- (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq,
- dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type));
- return;
- }
-
- /* Update receive rate in units of 64 * bytes/second */
- hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate;
- hctx->ccid3hctx_x_recv <<= 6;
+ /* Estimate RTT from history if ACK number is valid */
+ r_sample = tfrc_tx_hist_rtt(hctx->ccid3hctx_hist,
+ DCCP_SKB_CB(skb)->dccpd_ack_seq, now);
+ if (r_sample == 0) {
+ DCCP_WARN("%s(%p): %s with bogus ACK-%llu\n", dccp_role(sk), sk,
+ dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type),
+ (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq);
+ return;
+ }
- /* Update loss event rate */
- pinv = opt_recv->ccid3or_loss_event_rate;
- if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */
- hctx->ccid3hctx_p = 0;
- else /* can not exceed 100% */
- hctx->ccid3hctx_p = 1000000 / pinv;
+ /* Update receive rate in units of 64 * bytes/second */
+ hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate;
+ hctx->ccid3hctx_x_recv <<= 6;
- now = ktime_get_real();
- /*
- * Calculate new round trip sample as per [RFC 3448, 4.3] by
- * R_sample = (now - t_recvdata) - t_elapsed
- */
- r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, packet->dccphtx_tstamp));
+ /* Update loss event rate (which is scaled by 1e6) */
+ pinv = opt_recv->ccid3or_loss_event_rate;
+ if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */
+ hctx->ccid3hctx_p = 0;
+ else /* can not exceed 100% */
+ hctx->ccid3hctx_p = scaled_div(1, pinv);
+ /*
+ * Validate new RTT sample and update moving average
+ */
+ r_sample = dccp_sample_rtt(sk, r_sample);
+ hctx->ccid3hctx_rtt = tfrc_ewma(hctx->ccid3hctx_rtt, r_sample, 9);
+ /*
+ * Update allowed sending rate X as per draft rfc3448bis-00, 4.2/3
+ */
+ if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) {
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK);
- /*
- * Update RTT estimate by
- * If (No feedback recv)
- * R = R_sample;
- * Else
- * R = q * R + (1 - q) * R_sample;
- *
- * q is a constant, RFC 3448 recomments 0.9
- */
- if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) {
+ if (hctx->ccid3hctx_t_rto == 0) {
/*
- * Larger Initial Windows [RFC 4342, sec. 5]
+ * Initial feedback packet: Larger Initial Windows (4.2)
*/
- hctx->ccid3hctx_rtt = r_sample;
hctx->ccid3hctx_x = rfc3390_initial_rate(sk);
hctx->ccid3hctx_t_ld = now;
ccid3_update_send_interval(hctx);
- ccid3_pr_debug("%s(%p), s=%u, MSS=%u, "
- "R_sample=%uus, X=%u\n", dccp_role(sk),
- sk, hctx->ccid3hctx_s,
- dccp_sk(sk)->dccps_mss_cache, r_sample,
- (unsigned)(hctx->ccid3hctx_x >> 6));
-
- ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK);
- } else {
- hctx->ccid3hctx_rtt = (9 * hctx->ccid3hctx_rtt +
- r_sample) / 10;
-
- /* Update sending rate (step 4 of [RFC 3448, 4.3]) */
- if (hctx->ccid3hctx_p > 0)
- hctx->ccid3hctx_x_calc =
- tfrc_calc_x(hctx->ccid3hctx_s,
- hctx->ccid3hctx_rtt,
- hctx->ccid3hctx_p);
- ccid3_hc_tx_update_x(sk, &now);
-
- ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, "
- "p=%u, X_calc=%u, X_recv=%u, X=%u\n",
- dccp_role(sk),
- sk, hctx->ccid3hctx_rtt, r_sample,
- hctx->ccid3hctx_s, hctx->ccid3hctx_p,
- hctx->ccid3hctx_x_calc,
- (unsigned)(hctx->ccid3hctx_x_recv >> 6),
- (unsigned)(hctx->ccid3hctx_x >> 6));
+ goto done_computing_x;
+ } else if (hctx->ccid3hctx_p == 0) {
+ /*
+ * First feedback after nofeedback timer expiry (4.3)
+ */
+ goto done_computing_x;
}
+ }
- /* unschedule no feedback timer */
- sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
+ /* Update sending rate (step 4 of [RFC 3448, 4.3]) */
+ if (hctx->ccid3hctx_p > 0)
+ hctx->ccid3hctx_x_calc =
+ tfrc_calc_x(hctx->ccid3hctx_s,
+ hctx->ccid3hctx_rtt,
+ hctx->ccid3hctx_p);
+ ccid3_hc_tx_update_x(sk, &now);
+
+done_computing_x:
+ ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, "
+ "p=%u, X_calc=%u, X_recv=%u, X=%u\n",
+ dccp_role(sk),
+ sk, hctx->ccid3hctx_rtt, r_sample,
+ hctx->ccid3hctx_s, hctx->ccid3hctx_p,
+ hctx->ccid3hctx_x_calc,
+ (unsigned)(hctx->ccid3hctx_x_recv >> 6),
+ (unsigned)(hctx->ccid3hctx_x >> 6));
- /* remove all packets older than the one acked from history */
- dccp_tx_hist_purge_older(ccid3_tx_hist,
- &hctx->ccid3hctx_hist, packet);
- /*
- * As we have calculated new ipi, delta, t_nom it is possible
- * that we now can send a packet, so wake up dccp_wait_for_ccid
- */
- sk->sk_write_space(sk);
+ /* unschedule no feedback timer */
+ sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
- /*
- * Update timeout interval for the nofeedback timer.
- * We use a configuration option to increase the lower bound.
- * This can help avoid triggering the nofeedback timer too
- * often ('spinning') on LANs with small RTTs.
- */
- hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt,
- CONFIG_IP_DCCP_CCID3_RTO *
- (USEC_PER_SEC/1000));
- /*
- * Schedule no feedback timer to expire in
- * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi)
- */
- t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
+ /*
+ * As we have calculated new ipi, delta, t_nom it is possible
+ * that we now can send a packet, so wake up dccp_wait_for_ccid
+ */
+ sk->sk_write_space(sk);
- ccid3_pr_debug("%s(%p), Scheduled no feedback timer to "
- "expire in %lu jiffies (%luus)\n",
- dccp_role(sk),
- sk, usecs_to_jiffies(t_nfb), t_nfb);
+ /*
+ * Update timeout interval for the nofeedback timer.
+ * We use a configuration option to increase the lower bound.
+ * This can help avoid triggering the nofeedback timer too
+ * often ('spinning') on LANs with small RTTs.
+ */
+ hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt,
+ (CONFIG_IP_DCCP_CCID3_RTO *
+ (USEC_PER_SEC / 1000)));
+ /*
+ * Schedule no feedback timer to expire in
+ * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi)
+ */
+ t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
- sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
- jiffies + usecs_to_jiffies(t_nfb));
+ ccid3_pr_debug("%s(%p), Scheduled no feedback timer to "
+ "expire in %lu jiffies (%luus)\n",
+ dccp_role(sk),
+ sk, usecs_to_jiffies(t_nfb), t_nfb);
- /* set idle flag */
- hctx->ccid3hctx_idle = 1;
- break;
- case TFRC_SSTATE_NO_SENT: /* fall through */
- case TFRC_SSTATE_TERM: /* ignore feedback when closing */
- break;
- }
+ sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
+ jiffies + usecs_to_jiffies(t_nfb));
}
static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
@@ -605,12 +572,9 @@ static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk)
struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid);
hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT;
- INIT_LIST_HEAD(&hctx->ccid3hctx_hist);
-
- hctx->ccid3hctx_no_feedback_timer.function =
- ccid3_hc_tx_no_feedback_timer;
- hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk;
- init_timer(&hctx->ccid3hctx_no_feedback_timer);
+ hctx->ccid3hctx_hist = NULL;
+ setup_timer(&hctx->ccid3hctx_no_feedback_timer,
+ ccid3_hc_tx_no_feedback_timer, (unsigned long)sk);
return 0;
}
@@ -622,8 +586,7 @@ static void ccid3_hc_tx_exit(struct sock *sk)
ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM);
sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
- /* Empty packet history */
- dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist);
+ tfrc_tx_hist_purge(&hctx->ccid3hctx_hist);
}
static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info)
@@ -670,6 +633,15 @@ static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len,
/*
* Receiver Half-Connection Routines
*/
+
+/* CCID3 feedback types */
+enum ccid3_fback_type {
+ CCID3_FBACK_NONE = 0,
+ CCID3_FBACK_INITIAL,
+ CCID3_FBACK_PERIODIC,
+ CCID3_FBACK_PARAM_CHANGE
+};
+
#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state)
{
@@ -696,67 +668,58 @@ static void ccid3_hc_rx_set_state(struct sock *sk,
hcrx->ccid3hcrx_state = state;
}
-static inline void ccid3_hc_rx_update_s(struct ccid3_hc_rx_sock *hcrx, int len)
-{
- if (unlikely(len == 0)) /* don't update on empty packets (e.g. ACKs) */
- ccid3_pr_debug("Packet payload length is 0 - not updating\n");
- else
- hcrx->ccid3hcrx_s = hcrx->ccid3hcrx_s == 0 ? len :
- (9 * hcrx->ccid3hcrx_s + len) / 10;
-}
-
-static void ccid3_hc_rx_send_feedback(struct sock *sk)
+static void ccid3_hc_rx_send_feedback(struct sock *sk,
+ const struct sk_buff *skb,
+ enum ccid3_fback_type fbtype)
{
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
struct dccp_sock *dp = dccp_sk(sk);
- struct dccp_rx_hist_entry *packet;
ktime_t now;
- suseconds_t delta;
+ s64 delta = 0;
- ccid3_pr_debug("%s(%p) - entry \n", dccp_role(sk), sk);
+ if (unlikely(hcrx->ccid3hcrx_state == TFRC_RSTATE_TERM))
+ return;
now = ktime_get_real();
- switch (hcrx->ccid3hcrx_state) {
- case TFRC_RSTATE_NO_DATA:
+ switch (fbtype) {
+ case CCID3_FBACK_INITIAL:
hcrx->ccid3hcrx_x_recv = 0;
+ hcrx->ccid3hcrx_pinv = ~0U; /* see RFC 4342, 8.5 */
break;
- case TFRC_RSTATE_DATA:
- delta = ktime_us_delta(now,
- hcrx->ccid3hcrx_tstamp_last_feedback);
- DCCP_BUG_ON(delta < 0);
- hcrx->ccid3hcrx_x_recv =
- scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
+ case CCID3_FBACK_PARAM_CHANGE:
+ /*
+ * When parameters change (new loss or p > p_prev), we do not
+ * have a reliable estimate for R_m of [RFC 3448, 6.2] and so
+ * need to reuse the previous value of X_recv. However, when
+ * X_recv was 0 (due to early loss), this would kill X down to
+ * s/t_mbi (i.e. one packet in 64 seconds).
+ * To avoid such drastic reduction, we approximate X_recv as
+ * the number of bytes since last feedback.
+ * This is a safe fallback, since X is bounded above by X_calc.
+ */
+ if (hcrx->ccid3hcrx_x_recv > 0)
+ break;
+ /* fall through */
+ case CCID3_FBACK_PERIODIC:
+ delta = ktime_us_delta(now, hcrx->ccid3hcrx_tstamp_last_feedback);
+ if (delta <= 0)
+ DCCP_BUG("delta (%ld) <= 0", (long)delta);
+ else
+ hcrx->ccid3hcrx_x_recv =
+ scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
break;
- case TFRC_RSTATE_TERM:
- DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
+ default:
return;
}
- packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist);
- if (unlikely(packet == NULL)) {
- DCCP_WARN("%s(%p), no data packet in history!\n",
- dccp_role(sk), sk);
- return;
- }
+ ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", (long)delta,
+ hcrx->ccid3hcrx_x_recv, hcrx->ccid3hcrx_pinv);
hcrx->ccid3hcrx_tstamp_last_feedback = now;
- hcrx->ccid3hcrx_ccval_last_counter = packet->dccphrx_ccval;
+ hcrx->ccid3hcrx_last_counter = dccp_hdr(skb)->dccph_ccval;
hcrx->ccid3hcrx_bytes_recv = 0;
- /* Elapsed time information [RFC 4340, 13.2] in units of 10 * usecs */
- delta = ktime_us_delta(now, packet->dccphrx_tstamp);
- DCCP_BUG_ON(delta < 0);
- hcrx->ccid3hcrx_elapsed_time = delta / 10;
-
- if (hcrx->ccid3hcrx_p == 0)
- hcrx->ccid3hcrx_pinv = ~0U; /* see RFC 4342, 8.5 */
- else if (hcrx->ccid3hcrx_p > 1000000) {
- DCCP_WARN("p (%u) > 100%%\n", hcrx->ccid3hcrx_p);
- hcrx->ccid3hcrx_pinv = 1; /* use 100% in this case */
- } else
- hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p;
-
dp->dccps_hc_rx_insert_options = 1;
dccp_send_ack(sk);
}
@@ -770,7 +733,6 @@ static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
return 0;
hcrx = ccid3_hc_rx_sk(sk);
- DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_ccval_last_counter;
if (dccp_packet_without_ack(skb))
return 0;
@@ -778,11 +740,7 @@ static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
x_recv = htonl(hcrx->ccid3hcrx_x_recv);
pinv = htonl(hcrx->ccid3hcrx_pinv);
- if ((hcrx->ccid3hcrx_elapsed_time != 0 &&
- dccp_insert_option_elapsed_time(sk, skb,
- hcrx->ccid3hcrx_elapsed_time)) ||
- dccp_insert_option_timestamp(sk, skb) ||
- dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE,
+ if (dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE,
&pinv, sizeof(pinv)) ||
dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE,
&x_recv, sizeof(x_recv)))
@@ -791,180 +749,139 @@ static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
return 0;
}
-static int ccid3_hc_rx_detect_loss(struct sock *sk,
- struct dccp_rx_hist_entry *packet)
+/** ccid3_first_li - Implements [RFC 3448, 6.3.1]
+ *
+ * Determine the length of the first loss interval via inverse lookup.
+ * Assume that X_recv can be computed by the throughput equation
+ * s
+ * X_recv = --------
+ * R * fval
+ * Find some p such that f(p) = fval; return 1/p (scaled).
+ */
+static u32 ccid3_first_li(struct sock *sk)
{
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
- struct dccp_rx_hist_entry *rx_hist =
- dccp_rx_hist_head(&hcrx->ccid3hcrx_hist);
- u64 seqno = packet->dccphrx_seqno;
- u64 tmp_seqno;
- int loss = 0;
- u8 ccval;
-
-
- tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss;
+ u32 x_recv, p, delta;
+ u64 fval;
- if (!rx_hist ||
- follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) {
- hcrx->ccid3hcrx_seqno_nonloss = seqno;
- hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval;
- goto detect_out;
+ if (hcrx->ccid3hcrx_rtt == 0) {
+ DCCP_WARN("No RTT estimate available, using fallback RTT\n");
+ hcrx->ccid3hcrx_rtt = DCCP_FALLBACK_RTT;
}
-
- while (dccp_delta_seqno(hcrx->ccid3hcrx_seqno_nonloss, seqno)
- > TFRC_RECV_NUM_LATE_LOSS) {
- loss = 1;
- dccp_li_update_li(sk,
- &hcrx->ccid3hcrx_li_hist,
- &hcrx->ccid3hcrx_hist,
- hcrx->ccid3hcrx_tstamp_last_feedback,
- hcrx->ccid3hcrx_s,
- hcrx->ccid3hcrx_bytes_recv,
- hcrx->ccid3hcrx_x_recv,
- hcrx->ccid3hcrx_seqno_nonloss,
- hcrx->ccid3hcrx_ccval_nonloss);
- tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss;
- dccp_inc_seqno(&tmp_seqno);
- hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno;
- dccp_inc_seqno(&tmp_seqno);
- while (dccp_rx_hist_find_entry(&hcrx->ccid3hcrx_hist,
- tmp_seqno, &ccval)) {
- hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno;
- hcrx->ccid3hcrx_ccval_nonloss = ccval;
- dccp_inc_seqno(&tmp_seqno);
+ delta = ktime_to_us(net_timedelta(hcrx->ccid3hcrx_tstamp_last_feedback));
+ x_recv = scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
+ if (x_recv == 0) { /* would also trigger divide-by-zero */
+ DCCP_WARN("X_recv==0\n");
+ if ((x_recv = hcrx->ccid3hcrx_x_recv) == 0) {
+ DCCP_BUG("stored value of X_recv is zero");
+ return ~0U;
}
}
- /* FIXME - this code could be simplified with above while */
- /* but works at moment */
- if (follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) {
- hcrx->ccid3hcrx_seqno_nonloss = seqno;
- hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval;
- }
+ fval = scaled_div(hcrx->ccid3hcrx_s, hcrx->ccid3hcrx_rtt);
+ fval = scaled_div32(fval, x_recv);
+ p = tfrc_calc_x_reverse_lookup(fval);
-detect_out:
- dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist,
- &hcrx->ccid3hcrx_li_hist, packet,
- hcrx->ccid3hcrx_seqno_nonloss);
- return loss;
+ ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied "
+ "loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
+
+ return p == 0 ? ~0U : scaled_div(1, p);
}
static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
{
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
- const struct dccp_options_received *opt_recv;
- struct dccp_rx_hist_entry *packet;
- u32 p_prev, r_sample, rtt_prev;
- int loss, payload_size;
- ktime_t now;
-
- opt_recv = &dccp_sk(sk)->dccps_options_received;
-
- switch (DCCP_SKB_CB(skb)->dccpd_type) {
- case DCCP_PKT_ACK:
- if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
- return;
- case DCCP_PKT_DATAACK:
- if (opt_recv->dccpor_timestamp_echo == 0)
- break;
- r_sample = dccp_timestamp() - opt_recv->dccpor_timestamp_echo;
- rtt_prev = hcrx->ccid3hcrx_rtt;
- r_sample = dccp_sample_rtt(sk, 10 * r_sample);
+ enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE;
+ const u32 ndp = dccp_sk(sk)->dccps_options_received.dccpor_ndp;
+ const bool is_data_packet = dccp_data_packet(skb);
+
+ if (unlikely(hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)) {
+ if (is_data_packet) {
+ const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4;
+ do_feedback = CCID3_FBACK_INITIAL;
+ ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA);
+ hcrx->ccid3hcrx_s = payload;
+ /*
+ * Not necessary to update ccid3hcrx_bytes_recv here,
+ * since X_recv = 0 for the first feedback packet (cf.
+ * RFC 3448, 6.3) -- gerrit
+ */
+ }
+ goto update_records;
+ }
- if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
- hcrx->ccid3hcrx_rtt = r_sample;
- else
- hcrx->ccid3hcrx_rtt = (hcrx->ccid3hcrx_rtt * 9) / 10 +
- r_sample / 10;
+ if (tfrc_rx_hist_duplicate(&hcrx->ccid3hcrx_hist, skb))
+ return; /* done receiving */
- if (rtt_prev != hcrx->ccid3hcrx_rtt)
- ccid3_pr_debug("%s(%p), New RTT=%uus, elapsed time=%u\n",
- dccp_role(sk), sk, hcrx->ccid3hcrx_rtt,
- opt_recv->dccpor_elapsed_time);
- break;
- case DCCP_PKT_DATA:
- break;
- default: /* We're not interested in other packet types, move along */
- return;
+ if (is_data_packet) {
+ const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4;
+ /*
+ * Update moving-average of s and the sum of received payload bytes
+ */
+ hcrx->ccid3hcrx_s = tfrc_ewma(hcrx->ccid3hcrx_s, payload, 9);
+ hcrx->ccid3hcrx_bytes_recv += payload;
}
- packet = dccp_rx_hist_entry_new(ccid3_rx_hist, opt_recv->dccpor_ndp,
- skb, GFP_ATOMIC);
- if (unlikely(packet == NULL)) {
- DCCP_WARN("%s(%p), Not enough mem to add rx packet "
- "to history, consider it lost!\n", dccp_role(sk), sk);
- return;
+ /*
+ * Handle pending losses and otherwise check for new loss
+ */
+ if (tfrc_rx_hist_loss_pending(&hcrx->ccid3hcrx_hist) &&
+ tfrc_rx_handle_loss(&hcrx->ccid3hcrx_hist,
+ &hcrx->ccid3hcrx_li_hist,
+ skb, ndp, ccid3_first_li, sk) ) {
+ do_feedback = CCID3_FBACK_PARAM_CHANGE;
+ goto done_receiving;
}
- loss = ccid3_hc_rx_detect_loss(sk, packet);
+ if (tfrc_rx_hist_new_loss_indicated(&hcrx->ccid3hcrx_hist, skb, ndp))
+ goto update_records;
- if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK)
- return;
-
- payload_size = skb->len - dccp_hdr(skb)->dccph_doff * 4;
- ccid3_hc_rx_update_s(hcrx, payload_size);
+ /*
+ * Handle data packets: RTT sampling and monitoring p
+ */
+ if (unlikely(!is_data_packet))
+ goto update_records;
- switch (hcrx->ccid3hcrx_state) {
- case TFRC_RSTATE_NO_DATA:
- ccid3_pr_debug("%s(%p, state=%s), skb=%p, sending initial "
- "feedback\n", dccp_role(sk), sk,
- dccp_state_name(sk->sk_state), skb);
- ccid3_hc_rx_send_feedback(sk);
- ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA);
- return;
- case TFRC_RSTATE_DATA:
- hcrx->ccid3hcrx_bytes_recv += payload_size;
- if (loss)
- break;
+ if (!tfrc_lh_is_initialised(&hcrx->ccid3hcrx_li_hist)) {
+ const u32 sample = tfrc_rx_hist_sample_rtt(&hcrx->ccid3hcrx_hist, skb);
+ /*
+ * Empty loss history: no loss so far, hence p stays 0.
+ * Sample RTT values, since an RTT estimate is required for the
+ * computation of p when the first loss occurs; RFC 3448, 6.3.1.
+ */
+ if (sample != 0)
+ hcrx->ccid3hcrx_rtt = tfrc_ewma(hcrx->ccid3hcrx_rtt, sample, 9);
- now = ktime_get_real();
- if ((ktime_us_delta(now, hcrx->ccid3hcrx_tstamp_last_ack) -
- (s64)hcrx->ccid3hcrx_rtt) >= 0) {
- hcrx->ccid3hcrx_tstamp_last_ack = now;
- ccid3_hc_rx_send_feedback(sk);
- }
- return;
- case TFRC_RSTATE_TERM:
- DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
- return;
+ } else if (tfrc_lh_update_i_mean(&hcrx->ccid3hcrx_li_hist, skb)) {
+ /*
+ * Step (3) of [RFC 3448, 6.1]: Recompute I_mean and, if I_mean
+ * has decreased (resp. p has increased), send feedback now.
+ */
+ do_feedback = CCID3_FBACK_PARAM_CHANGE;
}
- /* Dealing with packet loss */
- ccid3_pr_debug("%s(%p, state=%s), data loss! Reacting...\n",
- dccp_role(sk), sk, dccp_state_name(sk->sk_state));
-
- p_prev = hcrx->ccid3hcrx_p;
-
- /* Calculate loss event rate */
- if (!list_empty(&hcrx->ccid3hcrx_li_hist)) {
- u32 i_mean = dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist);
+ /*
+ * Check if the periodic once-per-RTT feedback is due; RFC 4342, 10.3
+ */
+ if (SUB16(dccp_hdr(skb)->dccph_ccval, hcrx->ccid3hcrx_last_counter) > 3)
+ do_feedback = CCID3_FBACK_PERIODIC;
- /* Scaling up by 1000000 as fixed decimal */
- if (i_mean != 0)
- hcrx->ccid3hcrx_p = 1000000 / i_mean;
- } else
- DCCP_BUG("empty loss history");
+update_records:
+ tfrc_rx_hist_add_packet(&hcrx->ccid3hcrx_hist, skb, ndp);
- if (hcrx->ccid3hcrx_p > p_prev) {
- ccid3_hc_rx_send_feedback(sk);
- return;
- }
+done_receiving:
+ if (do_feedback)
+ ccid3_hc_rx_send_feedback(sk, skb, do_feedback);
}
static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk)
{
struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid);
- ccid3_pr_debug("entry\n");
-
hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA;
- INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist);
- INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist);
- hcrx->ccid3hcrx_tstamp_last_feedback =
- hcrx->ccid3hcrx_tstamp_last_ack = ktime_get_real();
- return 0;
+ tfrc_lh_init(&hcrx->ccid3hcrx_li_hist);
+ return tfrc_rx_hist_alloc(&hcrx->ccid3hcrx_hist);
}
static void ccid3_hc_rx_exit(struct sock *sk)
@@ -973,11 +890,8 @@ static void ccid3_hc_rx_exit(struct sock *sk)
ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM);
- /* Empty packet history */
- dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist);
-
- /* Empty loss interval history */
- dccp_li_hist_purge(&hcrx->ccid3hcrx_li_hist);
+ tfrc_rx_hist_purge(&hcrx->ccid3hcrx_hist);
+ tfrc_lh_cleanup(&hcrx->ccid3hcrx_li_hist);
}
static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info)
@@ -998,6 +912,7 @@ static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len,
u32 __user *optval, int __user *optlen)
{
const struct ccid3_hc_rx_sock *hcrx;
+ struct tfrc_rx_info rx_info;
const void *val;
/* Listen socks doesn't have a private CCID block */
@@ -1007,10 +922,14 @@ static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len,
hcrx = ccid3_hc_rx_sk(sk);
switch (optname) {
case DCCP_SOCKOPT_CCID_RX_INFO:
- if (len < sizeof(hcrx->ccid3hcrx_tfrc))
+ if (len < sizeof(rx_info))
return -EINVAL;
- len = sizeof(hcrx->ccid3hcrx_tfrc);
- val = &hcrx->ccid3hcrx_tfrc;
+ rx_info.tfrcrx_x_recv = hcrx->ccid3hcrx_x_recv;
+ rx_info.tfrcrx_rtt = hcrx->ccid3hcrx_rtt;
+ rx_info.tfrcrx_p = hcrx->ccid3hcrx_pinv == 0 ? ~0U :
+ scaled_div(1, hcrx->ccid3hcrx_pinv);
+ len = sizeof(rx_info);
+ val = &rx_info;
break;
default:
return -ENOPROTOOPT;
@@ -1024,7 +943,7 @@ static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len,
static struct ccid_operations ccid3 = {
.ccid_id = DCCPC_CCID3,
- .ccid_name = "ccid3",
+ .ccid_name = "TCP-Friendly Rate Control",
.ccid_owner = THIS_MODULE,
.ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock),
.ccid_hc_tx_init = ccid3_hc_tx_init,
@@ -1051,44 +970,13 @@ MODULE_PARM_DESC(ccid3_debug, "Enable debug messages");
static __init int ccid3_module_init(void)
{
- int rc = -ENOBUFS;
-
- ccid3_rx_hist = dccp_rx_hist_new("ccid3");
- if (ccid3_rx_hist == NULL)
- goto out;
-
- ccid3_tx_hist = dccp_tx_hist_new("ccid3");
- if (ccid3_tx_hist == NULL)
- goto out_free_rx;
-
- rc = ccid_register(&ccid3);
- if (rc != 0)
- goto out_free_tx;
-out:
- return rc;
-
-out_free_tx:
- dccp_tx_hist_delete(ccid3_tx_hist);
- ccid3_tx_hist = NULL;
-out_free_rx:
- dccp_rx_hist_delete(ccid3_rx_hist);
- ccid3_rx_hist = NULL;
- goto out;
+ return ccid_register(&ccid3);
}
module_init(ccid3_module_init);
static __exit void ccid3_module_exit(void)
{
ccid_unregister(&ccid3);
-
- if (ccid3_tx_hist != NULL) {
- dccp_tx_hist_delete(ccid3_tx_hist);
- ccid3_tx_hist = NULL;
- }
- if (ccid3_rx_hist != NULL) {
- dccp_rx_hist_delete(ccid3_rx_hist);
- ccid3_rx_hist = NULL;
- }
}
module_exit(ccid3_module_exit);
diff --git a/net/dccp/ccids/ccid3.h b/net/dccp/ccids/ccid3.h
index 0cdc982..49ca32b 100644
--- a/net/dccp/ccids/ccid3.h
+++ b/net/dccp/ccids/ccid3.h
@@ -1,7 +1,8 @@
/*
* net/dccp/ccids/ccid3.h
*
- * Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
+ * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand.
+ * Copyright (c) 2007 The University of Aberdeen, Scotland, UK
*
* An implementation of the DCCP protocol
*
@@ -40,6 +41,7 @@
#include <linux/list.h>
#include <linux/types.h>
#include <linux/tfrc.h>
+#include "lib/tfrc.h"
#include "../ccid.h"
/* Two seconds as per RFC 3448 4.2 */
@@ -88,7 +90,6 @@ enum ccid3_hc_tx_states {
* @ccid3hctx_t_last_win_count - Timestamp of earliest packet
* with last_win_count value sent
* @ccid3hctx_no_feedback_timer - Handle to no feedback timer
- * @ccid3hctx_idle - Flag indicating that sender is idling
* @ccid3hctx_t_ld - Time last doubled during slow start
* @ccid3hctx_t_nom - Nominal send time of next packet
* @ccid3hctx_delta - Send timer delta (RFC 3448, 4.6) in usecs
@@ -107,13 +108,12 @@ struct ccid3_hc_tx_sock {
u16 ccid3hctx_s;
enum ccid3_hc_tx_states ccid3hctx_state:8;
u8 ccid3hctx_last_win_count;
- u8 ccid3hctx_idle;
ktime_t ccid3hctx_t_last_win_count;
struct timer_list ccid3hctx_no_feedback_timer;
ktime_t ccid3hctx_t_ld;
ktime_t ccid3hctx_t_nom;
u32 ccid3hctx_delta;
- struct list_head ccid3hctx_hist;
+ struct tfrc_tx_hist_entry *ccid3hctx_hist;
struct ccid3_options_received ccid3hctx_options_received;
};
@@ -135,37 +135,30 @@ enum ccid3_hc_rx_states {
*
* @ccid3hcrx_x_recv - Receiver estimate of send rate (RFC 3448 4.3)
* @ccid3hcrx_rtt - Receiver estimate of rtt (non-standard)
- * @ccid3hcrx_p - current loss event rate (RFC 3448 5.4)
- * @ccid3hcrx_seqno_nonloss - Last received non-loss sequence number
- * @ccid3hcrx_ccval_nonloss - Last received non-loss Window CCVal
- * @ccid3hcrx_ccval_last_counter - Tracks window counter (RFC 4342, 8.1)
- * @ccid3hcrx_state - receiver state, one of %ccid3_hc_rx_states
+ * @ccid3hcrx_p - Current loss event rate (RFC 3448 5.4)
+ * @ccid3hcrx_last_counter - Tracks window counter (RFC 4342, 8.1)
+ * @ccid3hcrx_state - Receiver state, one of %ccid3_hc_rx_states
* @ccid3hcrx_bytes_recv - Total sum of DCCP payload bytes
+ * @ccid3hcrx_x_recv - Receiver estimate of send rate (RFC 3448, sec. 4.3)
+ * @ccid3hcrx_rtt - Receiver estimate of RTT
* @ccid3hcrx_tstamp_last_feedback - Time at which last feedback was sent
* @ccid3hcrx_tstamp_last_ack - Time at which last feedback was sent
- * @ccid3hcrx_hist - Packet history
- * @ccid3hcrx_li_hist - Loss Interval History
+ * @ccid3hcrx_hist - Packet history (loss detection + RTT sampling)
+ * @ccid3hcrx_li_hist - Loss Interval database
* @ccid3hcrx_s - Received packet size in bytes
* @ccid3hcrx_pinv - Inverse of Loss Event Rate (RFC 4342, sec. 8.5)
- * @ccid3hcrx_elapsed_time - Time since packet reception
*/
struct ccid3_hc_rx_sock {
- struct tfrc_rx_info ccid3hcrx_tfrc;
-#define ccid3hcrx_x_recv ccid3hcrx_tfrc.tfrcrx_x_recv
-#define ccid3hcrx_rtt ccid3hcrx_tfrc.tfrcrx_rtt
-#define ccid3hcrx_p ccid3hcrx_tfrc.tfrcrx_p
- u64 ccid3hcrx_seqno_nonloss:48,
- ccid3hcrx_ccval_nonloss:4,
- ccid3hcrx_ccval_last_counter:4;
+ u8 ccid3hcrx_last_counter:4;
enum ccid3_hc_rx_states ccid3hcrx_state:8;
u32 ccid3hcrx_bytes_recv;
+ u32 ccid3hcrx_x_recv;
+ u32 ccid3hcrx_rtt;
ktime_t ccid3hcrx_tstamp_last_feedback;
- ktime_t ccid3hcrx_tstamp_last_ack;
- struct list_head ccid3hcrx_hist;
- struct list_head ccid3hcrx_li_hist;
+ struct tfrc_rx_hist ccid3hcrx_hist;
+ struct tfrc_loss_hist ccid3hcrx_li_hist;
u16 ccid3hcrx_s;
- u32 ccid3hcrx_pinv;
- u32 ccid3hcrx_elapsed_time;
+#define ccid3hcrx_pinv ccid3hcrx_li_hist.i_mean
};
static inline struct ccid3_hc_rx_sock *ccid3_hc_rx_sk(const struct sock *sk)
diff --git a/net/dccp/ccids/lib/Makefile b/net/dccp/ccids/lib/Makefile
index 5f940a6..68c93e3 100644
--- a/net/dccp/ccids/lib/Makefile
+++ b/net/dccp/ccids/lib/Makefile
@@ -1,3 +1,3 @@
obj-$(CONFIG_IP_DCCP_TFRC_LIB) += dccp_tfrc_lib.o
-dccp_tfrc_lib-y := loss_interval.o packet_history.o tfrc_equation.o
+dccp_tfrc_lib-y := tfrc.o tfrc_equation.o packet_history.o loss_interval.o
diff --git a/net/dccp/ccids/lib/loss_interval.c b/net/dccp/ccids/lib/loss_interval.c
index d26b88d..849e181 100644
--- a/net/dccp/ccids/lib/loss_interval.c
+++ b/net/dccp/ccids/lib/loss_interval.c
@@ -1,6 +1,7 @@
/*
* net/dccp/ccids/lib/loss_interval.c
*
+ * Copyright (c) 2007 The University of Aberdeen, Scotland, UK
* Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand.
* Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz>
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
@@ -10,285 +11,176 @@
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
-
-#include <linux/module.h>
#include <net/sock.h>
-#include "../../dccp.h"
-#include "loss_interval.h"
-#include "packet_history.h"
#include "tfrc.h"
-#define DCCP_LI_HIST_IVAL_F_LENGTH 8
-
-struct dccp_li_hist_entry {
- struct list_head dccplih_node;
- u64 dccplih_seqno:48,
- dccplih_win_count:4;
- u32 dccplih_interval;
-};
+static struct kmem_cache *tfrc_lh_slab __read_mostly;
+/* Loss Interval weights from [RFC 3448, 5.4], scaled by 10 */
+static const int tfrc_lh_weights[NINTERVAL] = { 10, 10, 10, 10, 8, 6, 4, 2 };
-static struct kmem_cache *dccp_li_cachep __read_mostly;
-
-static inline struct dccp_li_hist_entry *dccp_li_hist_entry_new(const gfp_t prio)
+/* implements LIFO semantics on the array */
+static inline u8 LIH_INDEX(const u8 ctr)
{
- return kmem_cache_alloc(dccp_li_cachep, prio);
+ return (LIH_SIZE - 1 - (ctr % LIH_SIZE));
}
-static inline void dccp_li_hist_entry_delete(struct dccp_li_hist_entry *entry)
+/* the `counter' index always points at the next entry to be populated */
+static inline struct tfrc_loss_interval *tfrc_lh_peek(struct tfrc_loss_hist *lh)
{
- if (entry != NULL)
- kmem_cache_free(dccp_li_cachep, entry);
+ return lh->counter ? lh->ring[LIH_INDEX(lh->counter - 1)] : NULL;
}
-void dccp_li_hist_purge(struct list_head *list)
+/* given i with 0 <= i <= k, return I_i as per the rfc3448bis notation */
+static inline u32 tfrc_lh_get_interval(struct tfrc_loss_hist *lh, const u8 i)
{
- struct dccp_li_hist_entry *entry, *next;
-
- list_for_each_entry_safe(entry, next, list, dccplih_node) {
- list_del_init(&entry->dccplih_node);
- kmem_cache_free(dccp_li_cachep, entry);
- }
+ BUG_ON(i >= lh->counter);
+ return lh->ring[LIH_INDEX(lh->counter - i - 1)]->li_length;
}
-EXPORT_SYMBOL_GPL(dccp_li_hist_purge);
-
-/* Weights used to calculate loss event rate */
/*
- * These are integers as per section 8 of RFC3448. We can then divide by 4 *
- * when we use it.
+ * On-demand allocation and de-allocation of entries
*/
-static const int dccp_li_hist_w[DCCP_LI_HIST_IVAL_F_LENGTH] = {
- 4, 4, 4, 4, 3, 2, 1, 1,
-};
-
-u32 dccp_li_hist_calc_i_mean(struct list_head *list)
+static struct tfrc_loss_interval *tfrc_lh_demand_next(struct tfrc_loss_hist *lh)
{
- struct dccp_li_hist_entry *li_entry, *li_next;
- int i = 0;
- u32 i_tot;
- u32 i_tot0 = 0;
- u32 i_tot1 = 0;
- u32 w_tot = 0;
-
- list_for_each_entry_safe(li_entry, li_next, list, dccplih_node) {
- if (li_entry->dccplih_interval != ~0U) {
- i_tot0 += li_entry->dccplih_interval * dccp_li_hist_w[i];
- w_tot += dccp_li_hist_w[i];
- if (i != 0)
- i_tot1 += li_entry->dccplih_interval * dccp_li_hist_w[i - 1];
- }
-
-
- if (++i > DCCP_LI_HIST_IVAL_F_LENGTH)
- break;
- }
-
- if (i != DCCP_LI_HIST_IVAL_F_LENGTH)
- return 0;
-
- i_tot = max(i_tot0, i_tot1);
-
- if (!w_tot) {
- DCCP_WARN("w_tot = 0\n");
- return 1;
- }
-
- return i_tot / w_tot;
+ if (lh->ring[LIH_INDEX(lh->counter)] == NULL)
+ lh->ring[LIH_INDEX(lh->counter)] = kmem_cache_alloc(tfrc_lh_slab,
+ GFP_ATOMIC);
+ return lh->ring[LIH_INDEX(lh->counter)];
}
-EXPORT_SYMBOL_GPL(dccp_li_hist_calc_i_mean);
-
-static int dccp_li_hist_interval_new(struct list_head *list,
- const u64 seq_loss, const u8 win_loss)
+void tfrc_lh_cleanup(struct tfrc_loss_hist *lh)
{
- struct dccp_li_hist_entry *entry;
- int i;
-
- for (i = 0; i < DCCP_LI_HIST_IVAL_F_LENGTH; i++) {
- entry = dccp_li_hist_entry_new(GFP_ATOMIC);
- if (entry == NULL) {
- dccp_li_hist_purge(list);
- DCCP_BUG("loss interval list entry is NULL");
- return 0;
+ if (!tfrc_lh_is_initialised(lh))
+ return;
+
+ for (lh->counter = 0; lh->counter < LIH_SIZE; lh->counter++)
+ if (lh->ring[LIH_INDEX(lh->counter)] != NULL) {
+ kmem_cache_free(tfrc_lh_slab,
+ lh->ring[LIH_INDEX(lh->counter)]);
+ lh->ring[LIH_INDEX(lh->counter)] = NULL;
}
- entry->dccplih_interval = ~0;
- list_add(&entry->dccplih_node, list);
- }
-
- entry->dccplih_seqno = seq_loss;
- entry->dccplih_win_count = win_loss;
- return 1;
}
+EXPORT_SYMBOL_GPL(tfrc_lh_cleanup);
-/* calculate first loss interval
- *
- * returns estimated loss interval in usecs */
-static u32 dccp_li_calc_first_li(struct sock *sk,
- struct list_head *hist_list,
- ktime_t last_feedback,
- u16 s, u32 bytes_recv,
- u32 previous_x_recv)
+static void tfrc_lh_calc_i_mean(struct tfrc_loss_hist *lh)
{
- struct dccp_rx_hist_entry *entry, *next, *tail = NULL;
- u32 x_recv, p;
- suseconds_t rtt, delta;
- ktime_t tstamp = ktime_set(0, 0);
- int interval = 0;
- int win_count = 0;
- int step = 0;
- u64 fval;
+ u32 i_i, i_tot0 = 0, i_tot1 = 0, w_tot = 0;
+ int i, k = tfrc_lh_length(lh) - 1; /* k is as in rfc3448bis, 5.4 */
- list_for_each_entry_safe(entry, next, hist_list, dccphrx_node) {
- if (dccp_rx_hist_entry_data_packet(entry)) {
- tail = entry;
+ for (i=0; i <= k; i++) {
+ i_i = tfrc_lh_get_interval(lh, i);
- switch (step) {
- case 0:
- tstamp = entry->dccphrx_tstamp;
- win_count = entry->dccphrx_ccval;
- step = 1;
- break;
- case 1:
- interval = win_count - entry->dccphrx_ccval;
- if (interval < 0)
- interval += TFRC_WIN_COUNT_LIMIT;
- if (interval > 4)
- goto found;
- break;
- }
+ if (i < k) {
+ i_tot0 += i_i * tfrc_lh_weights[i];
+ w_tot += tfrc_lh_weights[i];
}
+ if (i > 0)
+ i_tot1 += i_i * tfrc_lh_weights[i-1];
}
- if (unlikely(step == 0)) {
- DCCP_WARN("%s(%p), packet history has no data packets!\n",
- dccp_role(sk), sk);
- return ~0;
- }
-
- if (unlikely(interval == 0)) {
- DCCP_WARN("%s(%p), Could not find a win_count interval > 0. "
- "Defaulting to 1\n", dccp_role(sk), sk);
- interval = 1;
- }
-found:
- if (!tail) {
- DCCP_CRIT("tail is null\n");
- return ~0;
- }
-
- delta = ktime_us_delta(tstamp, tail->dccphrx_tstamp);
- DCCP_BUG_ON(delta < 0);
+ BUG_ON(w_tot == 0);
+ lh->i_mean = max(i_tot0, i_tot1) / w_tot;
+}
- rtt = delta * 4 / interval;
- dccp_pr_debug("%s(%p), approximated RTT to %dus\n",
- dccp_role(sk), sk, (int)rtt);
+/**
+ * tfrc_lh_update_i_mean - Update the `open' loss interval I_0
+ * For recomputing p: returns `true' if p > p_prev <=> 1/p < 1/p_prev
+ */
+u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb)
+{
+ struct tfrc_loss_interval *cur = tfrc_lh_peek(lh);
+ u32 old_i_mean = lh->i_mean;
+ s64 length;
- /*
- * Determine the length of the first loss interval via inverse lookup.
- * Assume that X_recv can be computed by the throughput equation
- * s
- * X_recv = --------
- * R * fval
- * Find some p such that f(p) = fval; return 1/p [RFC 3448, 6.3.1].
- */
- if (rtt == 0) { /* would result in divide-by-zero */
- DCCP_WARN("RTT==0\n");
- return ~0;
- }
+ if (cur == NULL) /* not initialised */
+ return 0;
- delta = ktime_us_delta(ktime_get_real(), last_feedback);
- DCCP_BUG_ON(delta <= 0);
+ length = dccp_delta_seqno(cur->li_seqno, DCCP_SKB_CB(skb)->dccpd_seq);
- x_recv = scaled_div32(bytes_recv, delta);
- if (x_recv == 0) { /* would also trigger divide-by-zero */
- DCCP_WARN("X_recv==0\n");
- if (previous_x_recv == 0) {
- DCCP_BUG("stored value of X_recv is zero");
- return ~0;
- }
- x_recv = previous_x_recv;
- }
+ if (length - cur->li_length <= 0) /* duplicate or reordered */
+ return 0;
- fval = scaled_div(s, rtt);
- fval = scaled_div32(fval, x_recv);
- p = tfrc_calc_x_reverse_lookup(fval);
+ if (SUB16(dccp_hdr(skb)->dccph_ccval, cur->li_ccval) > 4)
+ /*
+ * Implements RFC 4342, 10.2:
+ * If a packet S (skb) exists whose seqno comes `after' the one
+ * starting the current loss interval (cur) and if the modulo-16
+ * distance from C(cur) to C(S) is greater than 4, consider all
+ * subsequent packets as belonging to a new loss interval. This
+ * test is necessary since CCVal may wrap between intervals.
+ */
+ cur->li_is_closed = 1;
+
+ if (tfrc_lh_length(lh) == 1) /* due to RFC 3448, 6.3.1 */
+ return 0;
- dccp_pr_debug("%s(%p), receive rate=%u bytes/s, implied "
- "loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
+ cur->li_length = length;
+ tfrc_lh_calc_i_mean(lh);
- if (p == 0)
- return ~0;
- else
- return 1000000 / p;
+ return (lh->i_mean < old_i_mean);
}
+EXPORT_SYMBOL_GPL(tfrc_lh_update_i_mean);
-void dccp_li_update_li(struct sock *sk,
- struct list_head *li_hist_list,
- struct list_head *hist_list,
- ktime_t last_feedback, u16 s, u32 bytes_recv,
- u32 previous_x_recv, u64 seq_loss, u8 win_loss)
+/* Determine if `new_loss' does begin a new loss interval [RFC 4342, 10.2] */
+static inline u8 tfrc_lh_is_new_loss(struct tfrc_loss_interval *cur,
+ struct tfrc_rx_hist_entry *new_loss)
{
- struct dccp_li_hist_entry *head;
- u64 seq_temp;
-
- if (list_empty(li_hist_list)) {
- if (!dccp_li_hist_interval_new(li_hist_list, seq_loss,
- win_loss))
- return;
-
- head = list_entry(li_hist_list->next, struct dccp_li_hist_entry,
- dccplih_node);
- head->dccplih_interval = dccp_li_calc_first_li(sk, hist_list,
- last_feedback,
- s, bytes_recv,
- previous_x_recv);
- } else {
- struct dccp_li_hist_entry *entry;
- struct list_head *tail;
+ return dccp_delta_seqno(cur->li_seqno, new_loss->tfrchrx_seqno) > 0 &&
+ (cur->li_is_closed || SUB16(new_loss->tfrchrx_ccval, cur->li_ccval) > 4);
+}
- head = list_entry(li_hist_list->next, struct dccp_li_hist_entry,
- dccplih_node);
- /* FIXME win count check removed as was wrong */
- /* should make this check with receive history */
- /* and compare there as per section 10.2 of RFC4342 */
+/** tfrc_lh_interval_add - Insert new record into the Loss Interval database
+ * @lh: Loss Interval database
+ * @rh: Receive history containing a fresh loss event
+ * @calc_first_li: Caller-dependent routine to compute length of first interval
+ * @sk: Used by @calc_first_li in caller-specific way (subtyping)
+ * Updates I_mean and returns 1 if a new interval has in fact been added to @lh.
+ */
+int tfrc_lh_interval_add(struct tfrc_loss_hist *lh, struct tfrc_rx_hist *rh,
+ u32 (*calc_first_li)(struct sock *), struct sock *sk)
+{
+ struct tfrc_loss_interval *cur = tfrc_lh_peek(lh), *new;
- /* new loss event detected */
- /* calculate last interval length */
- seq_temp = dccp_delta_seqno(head->dccplih_seqno, seq_loss);
- entry = dccp_li_hist_entry_new(GFP_ATOMIC);
+ if (cur != NULL && !tfrc_lh_is_new_loss(cur, tfrc_rx_hist_loss_prev(rh)))
+ return 0;
- if (entry == NULL) {
- DCCP_BUG("out of memory - can not allocate entry");
- return;
- }
+ new = tfrc_lh_demand_next(lh);
+ if (unlikely(new == NULL)) {
+ DCCP_CRIT("Cannot allocate/add loss record.");
+ return 0;
+ }
- list_add(&entry->dccplih_node, li_hist_list);
+ new->li_seqno = tfrc_rx_hist_loss_prev(rh)->tfrchrx_seqno;
+ new->li_ccval = tfrc_rx_hist_loss_prev(rh)->tfrchrx_ccval;
+ new->li_is_closed = 0;
- tail = li_hist_list->prev;
- list_del(tail);
- kmem_cache_free(dccp_li_cachep, tail);
+ if (++lh->counter == 1)
+ lh->i_mean = new->li_length = (*calc_first_li)(sk);
+ else {
+ cur->li_length = dccp_delta_seqno(cur->li_seqno, new->li_seqno);
+ new->li_length = dccp_delta_seqno(new->li_seqno,
+ tfrc_rx_hist_last_rcv(rh)->tfrchrx_seqno);
+ if (lh->counter > (2*LIH_SIZE))
+ lh->counter -= LIH_SIZE;
- /* Create the newest interval */
- entry->dccplih_seqno = seq_loss;
- entry->dccplih_interval = seq_temp;
- entry->dccplih_win_count = win_loss;
+ tfrc_lh_calc_i_mean(lh);
}
+ return 1;
}
+EXPORT_SYMBOL_GPL(tfrc_lh_interval_add);
-EXPORT_SYMBOL_GPL(dccp_li_update_li);
-
-static __init int dccp_li_init(void)
+int __init tfrc_li_init(void)
{
- dccp_li_cachep = kmem_cache_create("dccp_li_hist",
- sizeof(struct dccp_li_hist_entry),
- 0, SLAB_HWCACHE_ALIGN, NULL);
- return dccp_li_cachep == NULL ? -ENOBUFS : 0;
+ tfrc_lh_slab = kmem_cache_create("tfrc_li_hist",
+ sizeof(struct tfrc_loss_interval), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ return tfrc_lh_slab == NULL ? -ENOBUFS : 0;
}
-static __exit void dccp_li_exit(void)
+void tfrc_li_exit(void)
{
- kmem_cache_destroy(dccp_li_cachep);
+ if (tfrc_lh_slab != NULL) {
+ kmem_cache_destroy(tfrc_lh_slab);
+ tfrc_lh_slab = NULL;
+ }
}
-
-module_init(dccp_li_init);
-module_exit(dccp_li_exit);
diff --git a/net/dccp/ccids/lib/loss_interval.h b/net/dccp/ccids/lib/loss_interval.h
index 27bee92..246018a 100644
--- a/net/dccp/ccids/lib/loss_interval.h
+++ b/net/dccp/ccids/lib/loss_interval.h
@@ -3,6 +3,7 @@
/*
* net/dccp/ccids/lib/loss_interval.h
*
+ * Copyright (c) 2007 The University of Aberdeen, Scotland, UK
* Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand.
* Copyright (c) 2005-7 Ian McDonald <ian.mcdonald@jandi.co.nz>
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
@@ -12,18 +13,63 @@
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*/
-
#include <linux/ktime.h>
#include <linux/list.h>
+#include <linux/slab.h>
+
+/*
+ * Number of loss intervals (RFC 4342, 8.6.1). The history size is one more than
+ * NINTERVAL, since the `open' interval I_0 is always stored as the first entry.
+ */
+#define NINTERVAL 8
+#define LIH_SIZE (NINTERVAL + 1)
+
+/**
+ * tfrc_loss_interval - Loss history record for TFRC-based protocols
+ * @li_seqno: Highest received seqno before the start of loss
+ * @li_ccval: The CCVal belonging to @li_seqno
+ * @li_is_closed: Whether @li_seqno is older than 1 RTT
+ * @li_length: Loss interval sequence length
+ */
+struct tfrc_loss_interval {
+ u64 li_seqno:48,
+ li_ccval:4,
+ li_is_closed:1;
+ u32 li_length;
+};
+
+/**
+ * tfrc_loss_hist - Loss record database
+ * @ring: Circular queue managed in LIFO manner
+ * @counter: Current count of entries (can be more than %LIH_SIZE)
+ * @i_mean: Current Average Loss Interval [RFC 3448, 5.4]
+ */
+struct tfrc_loss_hist {
+ struct tfrc_loss_interval *ring[LIH_SIZE];
+ u8 counter;
+ u32 i_mean;
+};
+
+static inline void tfrc_lh_init(struct tfrc_loss_hist *lh)
+{
+ memset(lh, 0, sizeof(struct tfrc_loss_hist));
+}
+
+static inline u8 tfrc_lh_is_initialised(struct tfrc_loss_hist *lh)
+{
+ return lh->counter > 0;
+}
+
+static inline u8 tfrc_lh_length(struct tfrc_loss_hist *lh)
+{
+ return min(lh->counter, (u8)LIH_SIZE);
+}
-extern void dccp_li_hist_purge(struct list_head *list);
+struct tfrc_rx_hist;
-extern u32 dccp_li_hist_calc_i_mean(struct list_head *list);
+extern int tfrc_lh_interval_add(struct tfrc_loss_hist *, struct tfrc_rx_hist *,
+ u32 (*first_li)(struct sock *), struct sock *);
+extern u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *);
+extern void tfrc_lh_cleanup(struct tfrc_loss_hist *lh);
-extern void dccp_li_update_li(struct sock *sk,
- struct list_head *li_hist_list,
- struct list_head *hist_list,
- ktime_t last_feedback, u16 s,
- u32 bytes_recv, u32 previous_x_recv,
- u64 seq_loss, u8 win_loss);
#endif /* _DCCP_LI_HIST_ */
diff --git a/net/dccp/ccids/lib/packet_history.c b/net/dccp/ccids/lib/packet_history.c
index 34c4f60..20af1a6 100644
--- a/net/dccp/ccids/lib/packet_history.c
+++ b/net/dccp/ccids/lib/packet_history.c
@@ -1,7 +1,8 @@
/*
* net/dccp/packet_history.c
*
- * Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
+ * Copyright (c) 2007 The University of Aberdeen, Scotland, UK
+ * Copyright (c) 2005-7 The University of Waikato, Hamilton, New Zealand.
*
* An implementation of the DCCP protocol
*
@@ -34,267 +35,465 @@
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-#include <linux/module.h>
#include <linux/string.h>
+#include <linux/slab.h>
#include "packet_history.h"
+#include "../../dccp.h"
+
+/**
+ * tfrc_tx_hist_entry - Simple singly-linked TX history list
+ * @next: next oldest entry (LIFO order)
+ * @seqno: sequence number of this entry
+ * @stamp: send time of packet with sequence number @seqno
+ */
+struct tfrc_tx_hist_entry {
+ struct tfrc_tx_hist_entry *next;
+ u64 seqno;
+ ktime_t stamp;
+};
/*
- * Transmitter History Routines
+ * Transmitter History Routines
*/
-struct dccp_tx_hist *dccp_tx_hist_new(const char *name)
+static struct kmem_cache *tfrc_tx_hist_slab;
+
+int __init tfrc_tx_packet_history_init(void)
{
- struct dccp_tx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
- static const char dccp_tx_hist_mask[] = "tx_hist_%s";
- char *slab_name;
-
- if (hist == NULL)
- goto out;
-
- slab_name = kmalloc(strlen(name) + sizeof(dccp_tx_hist_mask) - 1,
- GFP_ATOMIC);
- if (slab_name == NULL)
- goto out_free_hist;
-
- sprintf(slab_name, dccp_tx_hist_mask, name);
- hist->dccptxh_slab = kmem_cache_create(slab_name,
- sizeof(struct dccp_tx_hist_entry),
- 0, SLAB_HWCACHE_ALIGN,
- NULL);
- if (hist->dccptxh_slab == NULL)
- goto out_free_slab_name;
-out:
- return hist;
-out_free_slab_name:
- kfree(slab_name);
-out_free_hist:
- kfree(hist);
- hist = NULL;
- goto out;
+ tfrc_tx_hist_slab = kmem_cache_create("tfrc_tx_hist",
+ sizeof(struct tfrc_tx_hist_entry),
+ 0, SLAB_HWCACHE_ALIGN, NULL);
+ return tfrc_tx_hist_slab == NULL ? -ENOBUFS : 0;
}
-EXPORT_SYMBOL_GPL(dccp_tx_hist_new);
-
-void dccp_tx_hist_delete(struct dccp_tx_hist *hist)
+void tfrc_tx_packet_history_exit(void)
{
- const char* name = kmem_cache_name(hist->dccptxh_slab);
-
- kmem_cache_destroy(hist->dccptxh_slab);
- kfree(name);
- kfree(hist);
+ if (tfrc_tx_hist_slab != NULL) {
+ kmem_cache_destroy(tfrc_tx_hist_slab);
+ tfrc_tx_hist_slab = NULL;
+ }
}
-EXPORT_SYMBOL_GPL(dccp_tx_hist_delete);
-
-struct dccp_tx_hist_entry *
- dccp_tx_hist_find_entry(const struct list_head *list, const u64 seq)
+static struct tfrc_tx_hist_entry *
+ tfrc_tx_hist_find_entry(struct tfrc_tx_hist_entry *head, u64 seqno)
{
- struct dccp_tx_hist_entry *packet = NULL, *entry;
-
- list_for_each_entry(entry, list, dccphtx_node)
- if (entry->dccphtx_seqno == seq) {
- packet = entry;
- break;
- }
+ while (head != NULL && head->seqno != seqno)
+ head = head->next;
- return packet;
+ return head;
}
-EXPORT_SYMBOL_GPL(dccp_tx_hist_find_entry);
+int tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno)
+{
+ struct tfrc_tx_hist_entry *entry = kmem_cache_alloc(tfrc_tx_hist_slab, gfp_any());
+
+ if (entry == NULL)
+ return -ENOBUFS;
+ entry->seqno = seqno;
+ entry->stamp = ktime_get_real();
+ entry->next = *headp;
+ *headp = entry;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(tfrc_tx_hist_add);
-void dccp_tx_hist_purge(struct dccp_tx_hist *hist, struct list_head *list)
+void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp)
{
- struct dccp_tx_hist_entry *entry, *next;
+ struct tfrc_tx_hist_entry *head = *headp;
+
+ while (head != NULL) {
+ struct tfrc_tx_hist_entry *next = head->next;
- list_for_each_entry_safe(entry, next, list, dccphtx_node) {
- list_del_init(&entry->dccphtx_node);
- dccp_tx_hist_entry_delete(hist, entry);
+ kmem_cache_free(tfrc_tx_hist_slab, head);
+ head = next;
}
-}
-EXPORT_SYMBOL_GPL(dccp_tx_hist_purge);
+ *headp = NULL;
+}
+EXPORT_SYMBOL_GPL(tfrc_tx_hist_purge);
-void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist,
- struct list_head *list,
- struct dccp_tx_hist_entry *packet)
+u32 tfrc_tx_hist_rtt(struct tfrc_tx_hist_entry *head, const u64 seqno,
+ const ktime_t now)
{
- struct dccp_tx_hist_entry *next;
+ u32 rtt = 0;
+ struct tfrc_tx_hist_entry *packet = tfrc_tx_hist_find_entry(head, seqno);
- list_for_each_entry_safe_continue(packet, next, list, dccphtx_node) {
- list_del_init(&packet->dccphtx_node);
- dccp_tx_hist_entry_delete(hist, packet);
+ if (packet != NULL) {
+ rtt = ktime_us_delta(now, packet->stamp);
+ /*
+ * Garbage-collect older (irrelevant) entries:
+ */
+ tfrc_tx_hist_purge(&packet->next);
}
+
+ return rtt;
}
+EXPORT_SYMBOL_GPL(tfrc_tx_hist_rtt);
-EXPORT_SYMBOL_GPL(dccp_tx_hist_purge_older);
/*
* Receiver History Routines
*/
-struct dccp_rx_hist *dccp_rx_hist_new(const char *name)
+static struct kmem_cache *tfrc_rx_hist_slab;
+
+int __init tfrc_rx_packet_history_init(void)
{
- struct dccp_rx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
- static const char dccp_rx_hist_mask[] = "rx_hist_%s";
- char *slab_name;
-
- if (hist == NULL)
- goto out;
-
- slab_name = kmalloc(strlen(name) + sizeof(dccp_rx_hist_mask) - 1,
- GFP_ATOMIC);
- if (slab_name == NULL)
- goto out_free_hist;
-
- sprintf(slab_name, dccp_rx_hist_mask, name);
- hist->dccprxh_slab = kmem_cache_create(slab_name,
- sizeof(struct dccp_rx_hist_entry),
- 0, SLAB_HWCACHE_ALIGN,
- NULL);
- if (hist->dccprxh_slab == NULL)
- goto out_free_slab_name;
-out:
- return hist;
-out_free_slab_name:
- kfree(slab_name);
-out_free_hist:
- kfree(hist);
- hist = NULL;
- goto out;
+ tfrc_rx_hist_slab = kmem_cache_create("tfrc_rxh_cache",
+ sizeof(struct tfrc_rx_hist_entry),
+ 0, SLAB_HWCACHE_ALIGN, NULL);
+ return tfrc_rx_hist_slab == NULL ? -ENOBUFS : 0;
}
-EXPORT_SYMBOL_GPL(dccp_rx_hist_new);
+void tfrc_rx_packet_history_exit(void)
+{
+ if (tfrc_rx_hist_slab != NULL) {
+ kmem_cache_destroy(tfrc_rx_hist_slab);
+ tfrc_rx_hist_slab = NULL;
+ }
+}
-void dccp_rx_hist_delete(struct dccp_rx_hist *hist)
+static inline void tfrc_rx_hist_entry_from_skb(struct tfrc_rx_hist_entry *entry,
+ const struct sk_buff *skb,
+ const u32 ndp)
{
- const char* name = kmem_cache_name(hist->dccprxh_slab);
+ const struct dccp_hdr *dh = dccp_hdr(skb);
- kmem_cache_destroy(hist->dccprxh_slab);
- kfree(name);
- kfree(hist);
+ entry->tfrchrx_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
+ entry->tfrchrx_ccval = dh->dccph_ccval;
+ entry->tfrchrx_type = dh->dccph_type;
+ entry->tfrchrx_ndp = ndp;
+ entry->tfrchrx_tstamp = ktime_get_real();
}
-EXPORT_SYMBOL_GPL(dccp_rx_hist_delete);
+void tfrc_rx_hist_add_packet(struct tfrc_rx_hist *h,
+ const struct sk_buff *skb,
+ const u32 ndp)
+{
+ struct tfrc_rx_hist_entry *entry = tfrc_rx_hist_last_rcv(h);
+
+ tfrc_rx_hist_entry_from_skb(entry, skb, ndp);
+}
+EXPORT_SYMBOL_GPL(tfrc_rx_hist_add_packet);
-int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
- u8 *ccval)
+/* has the packet contained in skb been seen before? */
+int tfrc_rx_hist_duplicate(struct tfrc_rx_hist *h, struct sk_buff *skb)
{
- struct dccp_rx_hist_entry *packet = NULL, *entry;
+ const u64 seq = DCCP_SKB_CB(skb)->dccpd_seq;
+ int i;
- list_for_each_entry(entry, list, dccphrx_node)
- if (entry->dccphrx_seqno == seq) {
- packet = entry;
- break;
- }
+ if (dccp_delta_seqno(tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno, seq) <= 0)
+ return 1;
- if (packet)
- *ccval = packet->dccphrx_ccval;
+ for (i = 1; i <= h->loss_count; i++)
+ if (tfrc_rx_hist_entry(h, i)->tfrchrx_seqno == seq)
+ return 1;
- return packet != NULL;
+ return 0;
}
+EXPORT_SYMBOL_GPL(tfrc_rx_hist_duplicate);
-EXPORT_SYMBOL_GPL(dccp_rx_hist_find_entry);
-struct dccp_rx_hist_entry *
- dccp_rx_hist_find_data_packet(const struct list_head *list)
+static void tfrc_rx_hist_swap(struct tfrc_rx_hist *h, const u8 a, const u8 b)
{
- struct dccp_rx_hist_entry *entry, *packet = NULL;
-
- list_for_each_entry(entry, list, dccphrx_node)
- if (entry->dccphrx_type == DCCP_PKT_DATA ||
- entry->dccphrx_type == DCCP_PKT_DATAACK) {
- packet = entry;
- break;
- }
+ const u8 idx_a = tfrc_rx_hist_index(h, a),
+ idx_b = tfrc_rx_hist_index(h, b);
+ struct tfrc_rx_hist_entry *tmp = h->ring[idx_a];
- return packet;
+ h->ring[idx_a] = h->ring[idx_b];
+ h->ring[idx_b] = tmp;
}
-EXPORT_SYMBOL_GPL(dccp_rx_hist_find_data_packet);
+/*
+ * Private helper functions for loss detection.
+ *
+ * In the descriptions, `Si' refers to the sequence number of entry number i,
+ * whose NDP count is `Ni' (lower case is used for variables).
+ * Note: All __after_loss functions expect that a test against duplicates has
+ * been performed already: the seqno of the skb must not be less than the
+ * seqno of loss_prev; and it must not equal that of any valid hist_entry.
+ */
+static void __one_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n2)
+{
+ u64 s0 = tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno,
+ s1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_seqno,
+ s2 = DCCP_SKB_CB(skb)->dccpd_seq;
+ int n1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_ndp,
+ d12 = dccp_delta_seqno(s1, s2), d2;
+
+ if (d12 > 0) { /* S1 < S2 */
+ h->loss_count = 2;
+ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 2), skb, n2);
+ return;
+ }
+
+ /* S0 < S2 < S1 */
+ d2 = dccp_delta_seqno(s0, s2);
-void dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
- struct list_head *rx_list,
- struct list_head *li_list,
- struct dccp_rx_hist_entry *packet,
- u64 nonloss_seqno)
+ if (d2 == 1 || n2 >= d2) { /* S2 is direct successor of S0 */
+ int d21 = -d12;
+
+ if (d21 == 1 || n1 >= d21) {
+ /* hole is filled: S0, S2, and S1 are consecutive */
+ h->loss_count = 0;
+ h->loss_start = tfrc_rx_hist_index(h, 1);
+ } else
+ /* gap between S2 and S1: just update loss_prev */
+ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_loss_prev(h), skb, n2);
+
+ } else { /* hole between S0 and S2 */
+ /*
+ * Reorder history to insert S2 between S0 and s1
+ */
+ tfrc_rx_hist_swap(h, 0, 3);
+ h->loss_start = tfrc_rx_hist_index(h, 3);
+ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 1), skb, n2);
+ h->loss_count = 2;
+ }
+}
+
+/* return 1 if a new loss event has been identified */
+static int __two_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n3)
{
- struct dccp_rx_hist_entry *entry, *next;
- u8 num_later = 0;
-
- list_add(&packet->dccphrx_node, rx_list);
-
- num_later = TFRC_RECV_NUM_LATE_LOSS + 1;
-
- if (!list_empty(li_list)) {
- list_for_each_entry_safe(entry, next, rx_list, dccphrx_node) {
- if (num_later == 0) {
- if (after48(nonloss_seqno,
- entry->dccphrx_seqno)) {
- list_del_init(&entry->dccphrx_node);
- dccp_rx_hist_entry_delete(hist, entry);
- }
- } else if (dccp_rx_hist_entry_data_packet(entry))
- --num_later;
- }
- } else {
- int step = 0;
- u8 win_count = 0; /* Not needed, but lets shut up gcc */
- int tmp;
+ u64 s0 = tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno,
+ s1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_seqno,
+ s2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_seqno,
+ s3 = DCCP_SKB_CB(skb)->dccpd_seq;
+ int n1 = tfrc_rx_hist_entry(h, 1)->tfrchrx_ndp,
+ d23 = dccp_delta_seqno(s2, s3), d13, d3, d31;
+
+ if (d23 > 0) { /* S2 < S3 */
+ h->loss_count = 3;
+ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 3), skb, n3);
+ return 1;
+ }
+
+ /* S3 < S2 */
+ d13 = dccp_delta_seqno(s1, s3);
+
+ if (d13 > 0) {
/*
- * We have no loss interval history so we need at least one
- * rtt:s of data packets to approximate rtt.
+ * The sequence number order is S1, S3, S2
+ * Reorder history to insert entry between S1 and S2
*/
- list_for_each_entry_safe(entry, next, rx_list, dccphrx_node) {
- if (num_later == 0) {
- switch (step) {
- case 0:
- step = 1;
- /* OK, find next data packet */
- num_later = 1;
- break;
- case 1:
- step = 2;
- /* OK, find next data packet */
- num_later = 1;
- win_count = entry->dccphrx_ccval;
- break;
- case 2:
- tmp = win_count - entry->dccphrx_ccval;
- if (tmp < 0)
- tmp += TFRC_WIN_COUNT_LIMIT;
- if (tmp > TFRC_WIN_COUNT_PER_RTT + 1) {
- /*
- * We have found a packet older
- * than one rtt remove the rest
- */
- step = 3;
- } else /* OK, find next data packet */
- num_later = 1;
- break;
- case 3:
- list_del_init(&entry->dccphrx_node);
- dccp_rx_hist_entry_delete(hist, entry);
- break;
- }
- } else if (dccp_rx_hist_entry_data_packet(entry))
- --num_later;
+ tfrc_rx_hist_swap(h, 2, 3);
+ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 2), skb, n3);
+ h->loss_count = 3;
+ return 1;
+ }
+
+ /* S0 < S3 < S1 */
+ d31 = -d13;
+ d3 = dccp_delta_seqno(s0, s3);
+
+ if (d3 == 1 || n3 >= d3) { /* S3 is a successor of S0 */
+
+ if (d31 == 1 || n1 >= d31) {
+ /* hole between S0 and S1 filled by S3 */
+ int d2 = dccp_delta_seqno(s1, s2),
+ n2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_ndp;
+
+ if (d2 == 1 || n2 >= d2) {
+ /* entire hole filled by S0, S3, S1, S2 */
+ h->loss_start = tfrc_rx_hist_index(h, 2);
+ h->loss_count = 0;
+ } else {
+ /* gap remains between S1 and S2 */
+ h->loss_start = tfrc_rx_hist_index(h, 1);
+ h->loss_count = 1;
+ }
+
+ } else /* gap exists between S3 and S1, loss_count stays at 2 */
+ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_loss_prev(h), skb, n3);
+
+ return 0;
+ }
+
+ /*
+ * The remaining case: S3 is not a successor of S0.
+ * Sequence order is S0, S3, S1, S2; reorder to insert between S0 and S1
+ */
+ tfrc_rx_hist_swap(h, 0, 3);
+ h->loss_start = tfrc_rx_hist_index(h, 3);
+ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 1), skb, n3);
+ h->loss_count = 3;
+
+ return 1;
+}
+
+/* return the signed modulo-2^48 sequence number distance from entry e1 to e2 */
+static s64 tfrc_rx_hist_delta_seqno(struct tfrc_rx_hist *h, u8 e1, u8 e2)
+{
+ DCCP_BUG_ON(e1 > h->loss_count || e2 > h->loss_count);
+
+ return dccp_delta_seqno(tfrc_rx_hist_entry(h, e1)->tfrchrx_seqno,
+ tfrc_rx_hist_entry(h, e2)->tfrchrx_seqno);
+}
+
+/* recycle RX history records to continue loss detection if necessary */
+static void __three_after_loss(struct tfrc_rx_hist *h)
+{
+ /*
+ * The distance between S0 and S1 is always greater than 1 and the NDP
+ * count of S1 is smaller than this distance. Otherwise there would
+ * have been no loss. Hence it is only necessary to see whether there
+ * are further missing data packets between S1/S2 and S2/S3.
+ */
+ int d2 = tfrc_rx_hist_delta_seqno(h, 1, 2),
+ d3 = tfrc_rx_hist_delta_seqno(h, 2, 3),
+ n2 = tfrc_rx_hist_entry(h, 2)->tfrchrx_ndp,
+ n3 = tfrc_rx_hist_entry(h, 3)->tfrchrx_ndp;
+
+ if (d2 == 1 || n2 >= d2) { /* S2 is successor to S1 */
+
+ if (d3 == 1 || n3 >= d3) {
+ /* S3 is successor of S2: entire hole is filled */
+ h->loss_start = tfrc_rx_hist_index(h, 3);
+ h->loss_count = 0;
+ } else {
+ /* gap between S2 and S3 */
+ h->loss_start = tfrc_rx_hist_index(h, 2);
+ h->loss_count = 1;
}
+
+ } else { /* gap between S1 and S2 */
+ h->loss_start = tfrc_rx_hist_index(h, 1);
+ h->loss_count = 2;
}
}
-EXPORT_SYMBOL_GPL(dccp_rx_hist_add_packet);
+/**
+ * tfrc_rx_handle_loss - Loss detection and further processing
+ * @h: The non-empty RX history object
+ * @lh: Loss Intervals database to update
+ * @skb: Currently received packet
+ * @ndp: The NDP count belonging to @skb
+ * @calc_first_li: Caller-dependent computation of first loss interval in @lh
+ * @sk: Used by @calc_first_li (see tfrc_lh_interval_add)
+ * Chooses action according to pending loss, updates LI database when a new
+ * loss was detected, and does required post-processing. Returns 1 when caller
+ * should send feedback, 0 otherwise.
+ */
+int tfrc_rx_handle_loss(struct tfrc_rx_hist *h,
+ struct tfrc_loss_hist *lh,
+ struct sk_buff *skb, u32 ndp,
+ u32 (*calc_first_li)(struct sock *), struct sock *sk)
+{
+ int is_new_loss = 0;
-void dccp_rx_hist_purge(struct dccp_rx_hist *hist, struct list_head *list)
+ if (h->loss_count == 1) {
+ __one_after_loss(h, skb, ndp);
+ } else if (h->loss_count != 2) {
+ DCCP_BUG("invalid loss_count %d", h->loss_count);
+ } else if (__two_after_loss(h, skb, ndp)) {
+ /*
+ * Update Loss Interval database and recycle RX records
+ */
+ is_new_loss = tfrc_lh_interval_add(lh, h, calc_first_li, sk);
+ __three_after_loss(h);
+ }
+ return is_new_loss;
+}
+EXPORT_SYMBOL_GPL(tfrc_rx_handle_loss);
+
+int tfrc_rx_hist_alloc(struct tfrc_rx_hist *h)
{
- struct dccp_rx_hist_entry *entry, *next;
+ int i;
+
+ for (i = 0; i <= TFRC_NDUPACK; i++) {
+ h->ring[i] = kmem_cache_alloc(tfrc_rx_hist_slab, GFP_ATOMIC);
+ if (h->ring[i] == NULL)
+ goto out_free;
+ }
+
+ h->loss_count = h->loss_start = 0;
+ return 0;
- list_for_each_entry_safe(entry, next, list, dccphrx_node) {
- list_del_init(&entry->dccphrx_node);
- kmem_cache_free(hist->dccprxh_slab, entry);
+out_free:
+ while (i-- != 0) {
+ kmem_cache_free(tfrc_rx_hist_slab, h->ring[i]);
+ h->ring[i] = NULL;
}
+ return -ENOBUFS;
}
+EXPORT_SYMBOL_GPL(tfrc_rx_hist_alloc);
+
+void tfrc_rx_hist_purge(struct tfrc_rx_hist *h)
+{
+ int i;
-EXPORT_SYMBOL_GPL(dccp_rx_hist_purge);
+ for (i = 0; i <= TFRC_NDUPACK; ++i)
+ if (h->ring[i] != NULL) {
+ kmem_cache_free(tfrc_rx_hist_slab, h->ring[i]);
+ h->ring[i] = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(tfrc_rx_hist_purge);
+/**
+ * tfrc_rx_hist_rtt_last_s - reference entry to compute RTT samples against
+ */
+static inline struct tfrc_rx_hist_entry *
+ tfrc_rx_hist_rtt_last_s(const struct tfrc_rx_hist *h)
+{
+ return h->ring[0];
+}
-MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, "
- "Arnaldo Carvalho de Melo <acme@ghostprotocols.net>");
-MODULE_DESCRIPTION("DCCP TFRC library");
-MODULE_LICENSE("GPL");
+/**
+ * tfrc_rx_hist_rtt_prev_s: previously suitable (wrt rtt_last_s) RTT-sampling entry
+ */
+static inline struct tfrc_rx_hist_entry *
+ tfrc_rx_hist_rtt_prev_s(const struct tfrc_rx_hist *h)
+{
+ return h->ring[h->rtt_sample_prev];
+}
+
+/**
+ * tfrc_rx_hist_sample_rtt - Sample RTT from timestamp / CCVal
+ * Based on ideas presented in RFC 4342, 8.1. Returns 0 if it was not able
+ * to compute a sample with given data - calling function should check this.
+ */
+u32 tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h, const struct sk_buff *skb)
+{
+ u32 sample = 0,
+ delta_v = SUB16(dccp_hdr(skb)->dccph_ccval,
+ tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval);
+
+ if (delta_v < 1 || delta_v > 4) { /* unsuitable CCVal delta */
+ if (h->rtt_sample_prev == 2) { /* previous candidate stored */
+ sample = SUB16(tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_ccval,
+ tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval);
+ if (sample)
+ sample = 4 / sample *
+ ktime_us_delta(tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_tstamp,
+ tfrc_rx_hist_rtt_last_s(h)->tfrchrx_tstamp);
+ else /*
+ * FIXME: This condition is in principle not
+ * possible but occurs when CCID is used for
+ * two-way data traffic. I have tried to trace
+ * it, but the cause does not seem to be here.
+ */
+ DCCP_BUG("please report to dccp@vger.kernel.org"
+ " => prev = %u, last = %u",
+ tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_ccval,
+ tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval);
+ } else if (delta_v < 1) {
+ h->rtt_sample_prev = 1;
+ goto keep_ref_for_next_time;
+ }
+
+ } else if (delta_v == 4) /* optimal match */
+ sample = ktime_to_us(net_timedelta(tfrc_rx_hist_rtt_last_s(h)->tfrchrx_tstamp));
+ else { /* suboptimal match */
+ h->rtt_sample_prev = 2;
+ goto keep_ref_for_next_time;
+ }
+
+ if (unlikely(sample > DCCP_SANE_RTT_MAX)) {
+ DCCP_WARN("RTT sample %u too large, using max\n", sample);
+ sample = DCCP_SANE_RTT_MAX;
+ }
+
+ h->rtt_sample_prev = 0; /* use current entry as next reference */
+keep_ref_for_next_time:
+
+ return sample;
+}
+EXPORT_SYMBOL_GPL(tfrc_rx_hist_sample_rtt);
diff --git a/net/dccp/ccids/lib/packet_history.h b/net/dccp/ccids/lib/packet_history.h
index 032bb61..c7eeda4 100644
--- a/net/dccp/ccids/lib/packet_history.h
+++ b/net/dccp/ccids/lib/packet_history.h
@@ -1,10 +1,9 @@
/*
- * net/dccp/packet_history.h
+ * Packet RX/TX history data structures and routines for TFRC-based protocols.
*
+ * Copyright (c) 2007 The University of Aberdeen, Scotland, UK
* Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
*
- * An implementation of the DCCP protocol
- *
* This code has been developed by the University of Waikato WAND
* research group. For further information please see http://www.wand.net.nz/
* or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz
@@ -37,165 +36,128 @@
#ifndef _DCCP_PKT_HIST_
#define _DCCP_PKT_HIST_
-#include <linux/ktime.h>
#include <linux/list.h>
#include <linux/slab.h>
+#include "tfrc.h"
-#include "../../dccp.h"
+struct tfrc_tx_hist_entry;
-/* Number of later packets received before one is considered lost */
-#define TFRC_RECV_NUM_LATE_LOSS 3
+extern int tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno);
+extern void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp);
+extern u32 tfrc_tx_hist_rtt(struct tfrc_tx_hist_entry *head,
+ const u64 seqno, const ktime_t now);
-#define TFRC_WIN_COUNT_PER_RTT 4
-#define TFRC_WIN_COUNT_LIMIT 16
+/* Subtraction a-b modulo-16, respects circular wrap-around */
+#define SUB16(a, b) (((a) + 16 - (b)) & 0xF)
-/*
- * Transmitter History data structures and declarations
+/* Number of packets to wait after a missing packet (RFC 4342, 6.1) */
+#define TFRC_NDUPACK 3
+
+/**
+ * tfrc_rx_hist_entry - Store information about a single received packet
+ * @tfrchrx_seqno: DCCP packet sequence number
+ * @tfrchrx_ccval: window counter value of packet (RFC 4342, 8.1)
+ * @tfrchrx_ndp: the NDP count (if any) of the packet
+ * @tfrchrx_tstamp: actual receive time of packet
*/
-struct dccp_tx_hist_entry {
- struct list_head dccphtx_node;
- u64 dccphtx_seqno:48,
- dccphtx_sent:1;
- u32 dccphtx_rtt;
- ktime_t dccphtx_tstamp;
+struct tfrc_rx_hist_entry {
+ u64 tfrchrx_seqno:48,
+ tfrchrx_ccval:4,
+ tfrchrx_type:4;
+ u32 tfrchrx_ndp; /* In fact it is from 8 to 24 bits */
+ ktime_t tfrchrx_tstamp;
};
-struct dccp_tx_hist {
- struct kmem_cache *dccptxh_slab;
+/**
+ * tfrc_rx_hist - RX history structure for TFRC-based protocols
+ *
+ * @ring: Packet history for RTT sampling and loss detection
+ * @loss_count: Number of entries in circular history
+ * @loss_start: Movable index (for loss detection)
+ * @rtt_sample_prev: Used during RTT sampling, points to candidate entry
+ */
+struct tfrc_rx_hist {
+ struct tfrc_rx_hist_entry *ring[TFRC_NDUPACK + 1];
+ u8 loss_count:2,
+ loss_start:2;
+#define rtt_sample_prev loss_start
};
-extern struct dccp_tx_hist *dccp_tx_hist_new(const char *name);
-extern void dccp_tx_hist_delete(struct dccp_tx_hist *hist);
-
-static inline struct dccp_tx_hist_entry *
- dccp_tx_hist_entry_new(struct dccp_tx_hist *hist,
- const gfp_t prio)
+/**
+ * tfrc_rx_hist_index - index to reach n-th entry after loss_start
+ */
+static inline u8 tfrc_rx_hist_index(const struct tfrc_rx_hist *h, const u8 n)
{
- struct dccp_tx_hist_entry *entry = kmem_cache_alloc(hist->dccptxh_slab,
- prio);
-
- if (entry != NULL)
- entry->dccphtx_sent = 0;
-
- return entry;
+ return (h->loss_start + n) & TFRC_NDUPACK;
}
-static inline struct dccp_tx_hist_entry *
- dccp_tx_hist_head(struct list_head *list)
+/**
+ * tfrc_rx_hist_last_rcv - entry with highest-received-seqno so far
+ */
+static inline struct tfrc_rx_hist_entry *
+ tfrc_rx_hist_last_rcv(const struct tfrc_rx_hist *h)
{
- struct dccp_tx_hist_entry *head = NULL;
-
- if (!list_empty(list))
- head = list_entry(list->next, struct dccp_tx_hist_entry,
- dccphtx_node);
- return head;
+ return h->ring[tfrc_rx_hist_index(h, h->loss_count)];
}
-extern struct dccp_tx_hist_entry *
- dccp_tx_hist_find_entry(const struct list_head *list,
- const u64 seq);
-
-static inline void dccp_tx_hist_add_entry(struct list_head *list,
- struct dccp_tx_hist_entry *entry)
+/**
+ * tfrc_rx_hist_entry - return the n-th history entry after loss_start
+ */
+static inline struct tfrc_rx_hist_entry *
+ tfrc_rx_hist_entry(const struct tfrc_rx_hist *h, const u8 n)
{
- list_add(&entry->dccphtx_node, list);
+ return h->ring[tfrc_rx_hist_index(h, n)];
}
-static inline void dccp_tx_hist_entry_delete(struct dccp_tx_hist *hist,
- struct dccp_tx_hist_entry *entry)
+/**
+ * tfrc_rx_hist_loss_prev - entry with highest-received-seqno before loss was detected
+ */
+static inline struct tfrc_rx_hist_entry *
+ tfrc_rx_hist_loss_prev(const struct tfrc_rx_hist *h)
{
- if (entry != NULL)
- kmem_cache_free(hist->dccptxh_slab, entry);
+ return h->ring[h->loss_start];
}
-extern void dccp_tx_hist_purge(struct dccp_tx_hist *hist,
- struct list_head *list);
-
-extern void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist,
- struct list_head *list,
- struct dccp_tx_hist_entry *next);
-
-/*
- * Receiver History data structures and declarations
- */
-struct dccp_rx_hist_entry {
- struct list_head dccphrx_node;
- u64 dccphrx_seqno:48,
- dccphrx_ccval:4,
- dccphrx_type:4;
- u32 dccphrx_ndp; /* In fact it is from 8 to 24 bits */
- ktime_t dccphrx_tstamp;
-};
-
-struct dccp_rx_hist {
- struct kmem_cache *dccprxh_slab;
-};
-
-extern struct dccp_rx_hist *dccp_rx_hist_new(const char *name);
-extern void dccp_rx_hist_delete(struct dccp_rx_hist *hist);
-
-static inline struct dccp_rx_hist_entry *
- dccp_rx_hist_entry_new(struct dccp_rx_hist *hist,
- const u32 ndp,
- const struct sk_buff *skb,
- const gfp_t prio)
+/* initialise loss detection and disable RTT sampling */
+static inline void tfrc_rx_hist_loss_indicated(struct tfrc_rx_hist *h)
{
- struct dccp_rx_hist_entry *entry = kmem_cache_alloc(hist->dccprxh_slab,
- prio);
-
- if (entry != NULL) {
- const struct dccp_hdr *dh = dccp_hdr(skb);
-
- entry->dccphrx_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
- entry->dccphrx_ccval = dh->dccph_ccval;
- entry->dccphrx_type = dh->dccph_type;
- entry->dccphrx_ndp = ndp;
- entry->dccphrx_tstamp = ktime_get_real();
- }
-
- return entry;
+ h->loss_count = 1;
}
-static inline struct dccp_rx_hist_entry *
- dccp_rx_hist_head(struct list_head *list)
+/* indicate whether previously a packet was detected missing */
+static inline int tfrc_rx_hist_loss_pending(const struct tfrc_rx_hist *h)
{
- struct dccp_rx_hist_entry *head = NULL;
-
- if (!list_empty(list))
- head = list_entry(list->next, struct dccp_rx_hist_entry,
- dccphrx_node);
- return head;
+ return h->loss_count;
}
-extern int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
- u8 *ccval);
-extern struct dccp_rx_hist_entry *
- dccp_rx_hist_find_data_packet(const struct list_head *list);
-
-extern void dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
- struct list_head *rx_list,
- struct list_head *li_list,
- struct dccp_rx_hist_entry *packet,
- u64 nonloss_seqno);
-
-static inline void dccp_rx_hist_entry_delete(struct dccp_rx_hist *hist,
- struct dccp_rx_hist_entry *entry)
+/* any data packets missing between last reception and skb ? */
+static inline int tfrc_rx_hist_new_loss_indicated(struct tfrc_rx_hist *h,
+ const struct sk_buff *skb,
+ u32 ndp)
{
- if (entry != NULL)
- kmem_cache_free(hist->dccprxh_slab, entry);
-}
+ int delta = dccp_delta_seqno(tfrc_rx_hist_last_rcv(h)->tfrchrx_seqno,
+ DCCP_SKB_CB(skb)->dccpd_seq);
-extern void dccp_rx_hist_purge(struct dccp_rx_hist *hist,
- struct list_head *list);
+ if (delta > 1 && ndp < delta)
+ tfrc_rx_hist_loss_indicated(h);
-static inline int
- dccp_rx_hist_entry_data_packet(const struct dccp_rx_hist_entry *entry)
-{
- return entry->dccphrx_type == DCCP_PKT_DATA ||
- entry->dccphrx_type == DCCP_PKT_DATAACK;
+ return tfrc_rx_hist_loss_pending(h);
}
-extern u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
- struct list_head *li_list, u8 *win_loss);
+extern void tfrc_rx_hist_add_packet(struct tfrc_rx_hist *h,
+ const struct sk_buff *skb, const u32 ndp);
+
+extern int tfrc_rx_hist_duplicate(struct tfrc_rx_hist *h, struct sk_buff *skb);
+
+struct tfrc_loss_hist;
+extern int tfrc_rx_handle_loss(struct tfrc_rx_hist *h,
+ struct tfrc_loss_hist *lh,
+ struct sk_buff *skb, u32 ndp,
+ u32 (*first_li)(struct sock *sk),
+ struct sock *sk);
+extern u32 tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h,
+ const struct sk_buff *skb);
+extern int tfrc_rx_hist_alloc(struct tfrc_rx_hist *h);
+extern void tfrc_rx_hist_purge(struct tfrc_rx_hist *h);
#endif /* _DCCP_PKT_HIST_ */
diff --git a/net/dccp/ccids/lib/tfrc.c b/net/dccp/ccids/lib/tfrc.c
new file mode 100644
index 0000000..d1dfbb8
--- /dev/null
+++ b/net/dccp/ccids/lib/tfrc.c
@@ -0,0 +1,63 @@
+/*
+ * TFRC: main module holding the pieces of the TFRC library together
+ *
+ * Copyright (c) 2007 The University of Aberdeen, Scotland, UK
+ * Copyright (c) 2007 Arnaldo Carvalho de Melo <acme@redhat.com>
+ */
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include "tfrc.h"
+
+#ifdef CONFIG_IP_DCCP_TFRC_DEBUG
+int tfrc_debug;
+module_param(tfrc_debug, bool, 0444);
+MODULE_PARM_DESC(tfrc_debug, "Enable debug messages");
+#endif
+
+extern int tfrc_tx_packet_history_init(void);
+extern void tfrc_tx_packet_history_exit(void);
+extern int tfrc_rx_packet_history_init(void);
+extern void tfrc_rx_packet_history_exit(void);
+
+extern int tfrc_li_init(void);
+extern void tfrc_li_exit(void);
+
+static int __init tfrc_module_init(void)
+{
+ int rc = tfrc_li_init();
+
+ if (rc)
+ goto out;
+
+ rc = tfrc_tx_packet_history_init();
+ if (rc)
+ goto out_free_loss_intervals;
+
+ rc = tfrc_rx_packet_history_init();
+ if (rc)
+ goto out_free_tx_history;
+ return 0;
+
+out_free_tx_history:
+ tfrc_tx_packet_history_exit();
+out_free_loss_intervals:
+ tfrc_li_exit();
+out:
+ return rc;
+}
+
+static void __exit tfrc_module_exit(void)
+{
+ tfrc_rx_packet_history_exit();
+ tfrc_tx_packet_history_exit();
+ tfrc_li_exit();
+}
+
+module_init(tfrc_module_init);
+module_exit(tfrc_module_exit);
+
+MODULE_AUTHOR("Gerrit Renker <gerrit@erg.abdn.ac.uk>, "
+ "Ian McDonald <ian.mcdonald@jandi.co.nz>, "
+ "Arnaldo Carvalho de Melo <acme@redhat.com>");
+MODULE_DESCRIPTION("DCCP TFRC library");
+MODULE_LICENSE("GPL");
diff --git a/net/dccp/ccids/lib/tfrc.h b/net/dccp/ccids/lib/tfrc.h
index faf5f7e..1fb1187 100644
--- a/net/dccp/ccids/lib/tfrc.h
+++ b/net/dccp/ccids/lib/tfrc.h
@@ -3,10 +3,11 @@
/*
* net/dccp/ccids/lib/tfrc.h
*
- * Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
- * Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz>
- * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
- * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
+ * Copyright (c) 2007 The University of Aberdeen, Scotland, UK
+ * Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
+ * Copyright (c) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.nz>
+ * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ * Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -15,6 +16,17 @@
*/
#include <linux/types.h>
#include <asm/div64.h>
+#include "../../dccp.h"
+/* internal includes that this module exports: */
+#include "loss_interval.h"
+#include "packet_history.h"
+
+#ifdef CONFIG_IP_DCCP_TFRC_DEBUG
+extern int tfrc_debug;
+#define tfrc_pr_debug(format, a...) DCCP_PR_DEBUG(tfrc_debug, format, ##a)
+#else
+#define tfrc_pr_debug(format, a...)
+#endif
/* integer-arithmetic divisions of type (a * 1000000)/b */
static inline u64 scaled_div(u64 a, u32 b)
@@ -37,6 +49,15 @@ static inline u32 scaled_div32(u64 a, u32 b)
return result;
}
+/**
+ * tfrc_ewma - Exponentially weighted moving average
+ * @weight: Weight to be used as damping factor, in units of 1/10
+ */
+static inline u32 tfrc_ewma(const u32 avg, const u32 newval, const u8 weight)
+{
+ return avg ? (weight * avg + (10 - weight) * newval) / 10 : newval;
+}
+
extern u32 tfrc_calc_x(u16 s, u32 R, u32 p);
extern u32 tfrc_calc_x_reverse_lookup(u32 fvalue);
diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h
index ee97950..ebe59d9 100644
--- a/net/dccp/dccp.h
+++ b/net/dccp/dccp.h
@@ -72,11 +72,21 @@ extern void dccp_time_wait(struct sock *sk, int state, int timeo);
/* RFC 1122, 4.2.3.1 initial RTO value */
#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ))
-#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */
+/*
+ * The maximum back-off value for retransmissions. This is needed for
+ * - retransmitting client-Requests (sec. 8.1.1),
+ * - retransmitting Close/CloseReq when closing (sec. 8.3),
+ * - feature-negotiation retransmission (sec. 6.6.3),
+ * - Acks in client-PARTOPEN state (sec. 8.1.5).
+ */
+#define DCCP_RTO_MAX ((unsigned)(64 * HZ))
-/* bounds for sampled RTT values from packet exchanges (in usec) */
+/*
+ * RTT sampling: sanity bounds and fallback RTT value from RFC 4340, section 3.4
+ */
#define DCCP_SANE_RTT_MIN 100
-#define DCCP_SANE_RTT_MAX (4 * USEC_PER_SEC)
+#define DCCP_FALLBACK_RTT (USEC_PER_SEC / 5)
+#define DCCP_SANE_RTT_MAX (3 * USEC_PER_SEC)
/* Maximal interval between probes for local resources. */
#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U))
@@ -143,12 +153,6 @@ static inline u64 max48(const u64 seq1, const u64 seq2)
return after48(seq1, seq2) ? seq1 : seq2;
}
-/* is seq1 next seqno after seq2 */
-static inline int follows48(const u64 seq1, const u64 seq2)
-{
- return dccp_delta_seqno(seq2, seq1) == 1;
-}
-
enum {
DCCP_MIB_NUM = 0,
DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */
@@ -334,6 +338,7 @@ struct dccp_skb_cb {
#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))
+/* RFC 4340, sec. 7.7 */
static inline int dccp_non_data_packet(const struct sk_buff *skb)
{
const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
@@ -346,6 +351,17 @@ static inline int dccp_non_data_packet(const struct sk_buff *skb)
type == DCCP_PKT_SYNCACK;
}
+/* RFC 4340, sec. 7.7 */
+static inline int dccp_data_packet(const struct sk_buff *skb)
+{
+ const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
+
+ return type == DCCP_PKT_DATA ||
+ type == DCCP_PKT_DATAACK ||
+ type == DCCP_PKT_REQUEST ||
+ type == DCCP_PKT_RESPONSE;
+}
+
static inline int dccp_packet_without_ack(const struct sk_buff *skb)
{
const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
@@ -406,6 +422,7 @@ static inline int dccp_ack_pending(const struct sock *sk)
}
extern int dccp_insert_options(struct sock *sk, struct sk_buff *skb);
+extern int dccp_insert_options_rsk(struct dccp_request_sock*, struct sk_buff*);
extern int dccp_insert_option_elapsed_time(struct sock *sk,
struct sk_buff *skb,
u32 elapsed_time);
diff --git a/net/dccp/feat.c b/net/dccp/feat.c
index 5ebdd86..4a4f6ce 100644
--- a/net/dccp/feat.c
+++ b/net/dccp/feat.c
@@ -4,10 +4,16 @@
* An implementation of the DCCP protocol
* Andrea Bittau <a.bittau@cs.ucl.ac.uk>
*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
+ * ASSUMPTIONS
+ * -----------
+ * o All currently known SP features have 1-byte quantities. If in the future
+ * extensions of RFCs 4340..42 define features with item lengths larger than
+ * one byte, a feature-specific extension of the code will be required.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
*/
#include <linux/module.h>
@@ -24,11 +30,7 @@ int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature,
dccp_feat_debug(type, feature, *val);
- if (!dccp_feat_is_valid_type(type)) {
- DCCP_WARN("option type %d invalid in negotiation\n", type);
- return 1;
- }
- if (!dccp_feat_is_valid_length(type, feature, len)) {
+ if (len > 3) {
DCCP_WARN("invalid length %d\n", len);
return 1;
}
@@ -99,7 +101,6 @@ static int dccp_feat_update_ccid(struct sock *sk, u8 type, u8 new_ccid_nr)
return 0;
}
-/* XXX taking only u8 vals */
static int dccp_feat_update(struct sock *sk, u8 type, u8 feat, u8 val)
{
dccp_feat_debug(type, feat, val);
@@ -144,7 +145,6 @@ static int dccp_feat_reconcile(struct sock *sk, struct dccp_opt_pend *opt,
/* FIXME sanity check vals */
/* Are values in any order? XXX Lame "algorithm" here */
- /* XXX assume values are 1 byte */
for (i = 0; i < slen; i++) {
for (j = 0; j < rlen; j++) {
if (spref[i] == rpref[j]) {
@@ -179,7 +179,6 @@ static int dccp_feat_reconcile(struct sock *sk, struct dccp_opt_pend *opt,
}
/* need to put result and our preference list */
- /* XXX assume 1 byte vals */
rlen = 1 + opt->dccpop_len;
rpref = kmalloc(rlen, GFP_ATOMIC);
if (rpref == NULL)
@@ -637,12 +636,12 @@ const char *dccp_feat_name(const u8 feat)
[DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage",
[DCCPF_DATA_CHECKSUM] = "Send Data Checksum",
};
+ if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC)
+ return feature_names[DCCPF_RESERVED];
+
if (feat >= DCCPF_MIN_CCID_SPECIFIC)
return "CCID-specific";
- if (dccp_feat_is_reserved(feat))
- return feature_names[DCCPF_RESERVED];
-
return feature_names[feat];
}
diff --git a/net/dccp/feat.h b/net/dccp/feat.h
index 177f7de..e272222 100644
--- a/net/dccp/feat.h
+++ b/net/dccp/feat.h
@@ -14,32 +14,6 @@
#include <linux/types.h>
#include "dccp.h"
-static inline int dccp_feat_is_valid_length(u8 type, u8 feature, u8 len)
-{
- /* sec. 6.1: Confirm has at least length 3,
- * sec. 6.2: Change has at least length 4 */
- if (len < 3)
- return 1;
- if (len < 4 && (type == DCCPO_CHANGE_L || type == DCCPO_CHANGE_R))
- return 1;
- /* XXX: add per-feature length validation (sec. 6.6.8) */
- return 0;
-}
-
-static inline int dccp_feat_is_reserved(const u8 feat)
-{
- return (feat > DCCPF_DATA_CHECKSUM &&
- feat < DCCPF_MIN_CCID_SPECIFIC) ||
- feat == DCCPF_RESERVED;
-}
-
-/* feature negotiation knows only these four option types (RFC 4340, sec. 6) */
-static inline int dccp_feat_is_valid_type(const u8 optnum)
-{
- return optnum >= DCCPO_CHANGE_L && optnum <= DCCPO_CONFIRM_R;
-
-}
-
#ifdef CONFIG_IP_DCCP_DEBUG
extern const char *dccp_feat_typename(const u8 type);
extern const char *dccp_feat_name(const u8 feat);
diff --git a/net/dccp/input.c b/net/dccp/input.c
index 1ce1010..08392ed 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -22,26 +22,77 @@
/* rate-limit for syncs in reply to sequence-invalid packets; RFC 4340, 7.5.4 */
int sysctl_dccp_sync_ratelimit __read_mostly = HZ / 8;
-static void dccp_fin(struct sock *sk, struct sk_buff *skb)
+static void dccp_enqueue_skb(struct sock *sk, struct sk_buff *skb)
{
- sk->sk_shutdown |= RCV_SHUTDOWN;
- sock_set_flag(sk, SOCK_DONE);
__skb_pull(skb, dccp_hdr(skb)->dccph_doff * 4);
__skb_queue_tail(&sk->sk_receive_queue, skb);
skb_set_owner_r(skb, sk);
sk->sk_data_ready(sk, 0);
}
-static void dccp_rcv_close(struct sock *sk, struct sk_buff *skb)
+static void dccp_fin(struct sock *sk, struct sk_buff *skb)
{
- dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED);
- dccp_fin(sk, skb);
- dccp_set_state(sk, DCCP_CLOSED);
- sk_wake_async(sk, 1, POLL_HUP);
+ /*
+ * On receiving Close/CloseReq, both RD/WR shutdown are performed.
+ * RFC 4340, 8.3 says that we MAY send further Data/DataAcks after
+ * receiving the closing segment, but there is no guarantee that such
+ * data will be processed at all.
+ */
+ sk->sk_shutdown = SHUTDOWN_MASK;
+ sock_set_flag(sk, SOCK_DONE);
+ dccp_enqueue_skb(sk, skb);
+}
+
+static int dccp_rcv_close(struct sock *sk, struct sk_buff *skb)
+{
+ int queued = 0;
+
+ switch (sk->sk_state) {
+ /*
+ * We ignore Close when received in one of the following states:
+ * - CLOSED (may be a late or duplicate packet)
+ * - PASSIVE_CLOSEREQ (the peer has sent a CloseReq earlier)
+ * - RESPOND (already handled by dccp_check_req)
+ */
+ case DCCP_CLOSING:
+ /*
+ * Simultaneous-close: receiving a Close after sending one. This
+ * can happen if both client and server perform active-close and
+ * will result in an endless ping-pong of crossing and retrans-
+ * mitted Close packets, which only terminates when one of the
+ * nodes times out (min. 64 seconds). Quicker convergence can be
+ * achieved when one of the nodes acts as tie-breaker.
+ * This is ok as both ends are done with data transfer and each
+ * end is just waiting for the other to acknowledge termination.
+ */
+ if (dccp_sk(sk)->dccps_role != DCCP_ROLE_CLIENT)
+ break;
+ /* fall through */
+ case DCCP_REQUESTING:
+ case DCCP_ACTIVE_CLOSEREQ:
+ dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED);
+ dccp_done(sk);
+ break;
+ case DCCP_OPEN:
+ case DCCP_PARTOPEN:
+ /* Give waiting application a chance to read pending data */
+ queued = 1;
+ dccp_fin(sk, skb);
+ dccp_set_state(sk, DCCP_PASSIVE_CLOSE);
+ /* fall through */
+ case DCCP_PASSIVE_CLOSE:
+ /*
+ * Retransmitted Close: we have already enqueued the first one.
+ */
+ sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP);
+ }
+ return queued;
}
-static void dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb)
+static int dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb)
{
+ int queued = 0;
+
/*
* Step 7: Check for unexpected packet types
* If (S.is_server and P.type == CloseReq)
@@ -50,12 +101,26 @@ static void dccp_rcv_closereq(struct sock *sk, struct sk_buff *skb)
*/
if (dccp_sk(sk)->dccps_role != DCCP_ROLE_CLIENT) {
dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC);
- return;
+ return queued;
}
- if (sk->sk_state != DCCP_CLOSING)
+ /* Step 13: process relevant Client states < CLOSEREQ */
+ switch (sk->sk_state) {
+ case DCCP_REQUESTING:
+ dccp_send_close(sk, 0);
dccp_set_state(sk, DCCP_CLOSING);
- dccp_send_close(sk, 0);
+ break;
+ case DCCP_OPEN:
+ case DCCP_PARTOPEN:
+ /* Give waiting application a chance to read pending data */
+ queued = 1;
+ dccp_fin(sk, skb);
+ dccp_set_state(sk, DCCP_PASSIVE_CLOSEREQ);
+ /* fall through */
+ case DCCP_PASSIVE_CLOSEREQ:
+ sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP);
+ }
+ return queued;
}
static u8 dccp_reset_code_convert(const u8 code)
@@ -90,7 +155,7 @@ static void dccp_rcv_reset(struct sock *sk, struct sk_buff *skb)
dccp_fin(sk, skb);
if (err && !sock_flag(sk, SOCK_DEAD))
- sk_wake_async(sk, 0, POLL_ERR);
+ sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
dccp_time_wait(sk, DCCP_TIME_WAIT, 0);
}
@@ -103,6 +168,21 @@ static void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb)
DCCP_SKB_CB(skb)->dccpd_ack_seq);
}
+static void dccp_deliver_input_to_ccids(struct sock *sk, struct sk_buff *skb)
+{
+ const struct dccp_sock *dp = dccp_sk(sk);
+
+ /* Don't deliver to RX CCID when node has shut down read end. */
+ if (!(sk->sk_shutdown & RCV_SHUTDOWN))
+ ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
+ /*
+ * Until the TX queue has been drained, we can not honour SHUT_WR, since
+ * we need received feedback as input to adjust congestion control.
+ */
+ if (sk->sk_write_queue.qlen > 0 || !(sk->sk_shutdown & SEND_SHUTDOWN))
+ ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
+}
+
static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb)
{
const struct dccp_hdr *dh = dccp_hdr(skb);
@@ -209,13 +289,11 @@ static int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
case DCCP_PKT_DATAACK:
case DCCP_PKT_DATA:
/*
- * FIXME: check if sk_receive_queue is full, schedule DATA_DROPPED
- * option if it is.
+ * FIXME: schedule DATA_DROPPED (RFC 4340, 11.7.2) if and when
+ * - sk_shutdown == RCV_SHUTDOWN, use Code 1, "Not Listening"
+ * - sk_receive_queue is full, use Code 2, "Receive Buffer"
*/
- __skb_pull(skb, dh->dccph_doff * 4);
- __skb_queue_tail(&sk->sk_receive_queue, skb);
- skb_set_owner_r(skb, sk);
- sk->sk_data_ready(sk, 0);
+ dccp_enqueue_skb(sk, skb);
return 0;
case DCCP_PKT_ACK:
goto discard;
@@ -231,11 +309,13 @@ static int __dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
dccp_rcv_reset(sk, skb);
return 0;
case DCCP_PKT_CLOSEREQ:
- dccp_rcv_closereq(sk, skb);
+ if (dccp_rcv_closereq(sk, skb))
+ return 0;
goto discard;
case DCCP_PKT_CLOSE:
- dccp_rcv_close(sk, skb);
- return 0;
+ if (dccp_rcv_close(sk, skb))
+ return 0;
+ goto discard;
case DCCP_PKT_REQUEST:
/* Step 7
* or (S.is_server and P.type == Response)
@@ -289,7 +369,7 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
if (dccp_check_seqno(sk, skb))
goto discard;
- if (dccp_parse_options(sk, skb))
+ if (dccp_parse_options(sk, NULL, skb))
goto discard;
if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
@@ -300,9 +380,7 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
DCCP_SKB_CB(skb)->dccpd_seq,
DCCP_ACKVEC_STATE_RECEIVED))
goto discard;
-
- ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
- ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
+ dccp_deliver_input_to_ccids(sk, skb);
return __dccp_rcv_established(sk, skb, dh, len);
discard:
@@ -349,7 +427,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
goto out_invalid_packet;
}
- if (dccp_parse_options(sk, skb))
+ if (dccp_parse_options(sk, NULL, skb))
goto out_invalid_packet;
/* Obtain usec RTT sample from SYN exchange (used by CCID 3) */
@@ -402,7 +480,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
if (!sock_flag(sk, SOCK_DEAD)) {
sk->sk_state_change(sk);
- sk_wake_async(sk, 0, POLL_OUT);
+ sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT);
}
if (sk->sk_write_pending || icsk->icsk_ack.pingpong ||
@@ -531,7 +609,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
/*
* Step 8: Process options and mark acknowledgeable
*/
- if (dccp_parse_options(sk, skb))
+ if (dccp_parse_options(sk, NULL, skb))
goto discard;
if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
@@ -543,8 +621,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
DCCP_ACKVEC_STATE_RECEIVED))
goto discard;
- ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
- ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
+ dccp_deliver_input_to_ccids(sk, skb);
}
/*
@@ -560,16 +637,14 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
return 0;
/*
* Step 7: Check for unexpected packet types
- * If (S.is_server and P.type == CloseReq)
- * or (S.is_server and P.type == Response)
+ * If (S.is_server and P.type == Response)
* or (S.is_client and P.type == Request)
* or (S.state == RESPOND and P.type == Data),
* Send Sync packet acknowledging P.seqno
* Drop packet and return
*/
} else if ((dp->dccps_role != DCCP_ROLE_CLIENT &&
- (dh->dccph_type == DCCP_PKT_RESPONSE ||
- dh->dccph_type == DCCP_PKT_CLOSEREQ)) ||
+ dh->dccph_type == DCCP_PKT_RESPONSE) ||
(dp->dccps_role == DCCP_ROLE_CLIENT &&
dh->dccph_type == DCCP_PKT_REQUEST) ||
(sk->sk_state == DCCP_RESPOND &&
@@ -577,11 +652,13 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC);
goto discard;
} else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) {
- dccp_rcv_closereq(sk, skb);
+ if (dccp_rcv_closereq(sk, skb))
+ return 0;
goto discard;
} else if (dh->dccph_type == DCCP_PKT_CLOSE) {
- dccp_rcv_close(sk, skb);
- return 0;
+ if (dccp_rcv_close(sk, skb))
+ return 0;
+ goto discard;
}
switch (sk->sk_state) {
@@ -611,7 +688,7 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
switch (old_state) {
case DCCP_PARTOPEN:
sk->sk_state_change(sk);
- sk_wake_async(sk, 0, POLL_OUT);
+ sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT);
break;
}
} else if (unlikely(dh->dccph_type == DCCP_PKT_SYNC)) {
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index db17b83..9e38b0d 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -408,7 +408,7 @@ struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb,
dccp_sync_mss(newsk, dst_mtu(dst));
- __inet_hash(&dccp_hashinfo, newsk, 0);
+ __inet_hash_nolisten(&dccp_hashinfo, newsk);
__inet_inherit_port(&dccp_hashinfo, sk, newsk);
return newsk;
@@ -469,7 +469,7 @@ static struct dst_entry* dccp_v4_route_skb(struct sock *sk,
};
security_skb_classify_flow(skb, &fl);
- if (ip_route_output_flow(&rt, &fl, sk, 0)) {
+ if (ip_route_output_flow(&init_net, &rt, &fl, sk, 0)) {
IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
return NULL;
}
@@ -600,11 +600,12 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
if (req == NULL)
goto drop;
- if (dccp_parse_options(sk, skb))
- goto drop_and_free;
-
dccp_reqsk_init(req, skb);
+ dreq = dccp_rsk(req);
+ if (dccp_parse_options(sk, dreq, skb))
+ goto drop_and_free;
+
if (security_inet_conn_request(sk, skb, req))
goto drop_and_free;
@@ -621,7 +622,6 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
* In fact we defer setting S.GSR, S.SWL, S.SWH to
* dccp_create_openreq_child.
*/
- dreq = dccp_rsk(req);
dreq->dreq_isr = dcb->dccpd_seq;
dreq->dreq_iss = dccp_v4_init_sequence(skb);
dreq->dreq_service = service;
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 87c98fb..f42b75c 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -415,11 +415,12 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (req == NULL)
goto drop;
- if (dccp_parse_options(sk, skb))
- goto drop_and_free;
-
dccp_reqsk_init(req, skb);
+ dreq = dccp_rsk(req);
+ if (dccp_parse_options(sk, dreq, skb))
+ goto drop_and_free;
+
if (security_inet_conn_request(sk, skb, req))
goto drop_and_free;
@@ -449,7 +450,6 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
* In fact we defer setting S.GSR, S.SWL, S.SWH to
* dccp_create_openreq_child.
*/
- dreq = dccp_rsk(req);
dreq->dreq_isr = dcb->dccpd_seq;
dreq->dreq_iss = dccp_v6_init_sequence(skb);
dreq->dreq_service = service;
@@ -994,7 +994,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
if (final_p)
ipv6_addr_copy(&fl.fl6_dst, final_p);
- err = __xfrm_lookup(&dst, &fl, sk, 1);
+ err = __xfrm_lookup(&dst, &fl, sk, XFRM_LOOKUP_WAIT);
if (err < 0) {
if (err == -EREMOTE)
err = ip6_dst_blackhole(sk, &dst, &fl);
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index 831b76e..027d181 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -117,11 +117,13 @@ struct sock *dccp_create_openreq_child(struct sock *sk,
struct dccp_sock *newdp = dccp_sk(newsk);
struct dccp_minisock *newdmsk = dccp_msk(newsk);
- newdp->dccps_role = DCCP_ROLE_SERVER;
- newdp->dccps_hc_rx_ackvec = NULL;
- newdp->dccps_service_list = NULL;
- newdp->dccps_service = dreq->dreq_service;
- newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
+ newdp->dccps_role = DCCP_ROLE_SERVER;
+ newdp->dccps_hc_rx_ackvec = NULL;
+ newdp->dccps_service_list = NULL;
+ newdp->dccps_service = dreq->dreq_service;
+ newdp->dccps_timestamp_echo = dreq->dreq_timestamp_echo;
+ newdp->dccps_timestamp_time = dreq->dreq_timestamp_time;
+ newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
if (dccp_feat_clone(sk, newsk))
goto out_free;
@@ -200,10 +202,10 @@ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
struct request_sock **prev)
{
struct sock *child = NULL;
+ struct dccp_request_sock *dreq = dccp_rsk(req);
/* Check for retransmitted REQUEST */
if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) {
- struct dccp_request_sock *dreq = dccp_rsk(req);
if (after48(DCCP_SKB_CB(skb)->dccpd_seq, dreq->dreq_isr)) {
dccp_pr_debug("Retransmitted REQUEST\n");
@@ -227,22 +229,22 @@ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
goto drop;
/* Invalid ACK */
- if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dccp_rsk(req)->dreq_iss) {
+ if (DCCP_SKB_CB(skb)->dccpd_ack_seq != dreq->dreq_iss) {
dccp_pr_debug("Invalid ACK number: ack_seq=%llu, "
"dreq_iss=%llu\n",
(unsigned long long)
DCCP_SKB_CB(skb)->dccpd_ack_seq,
- (unsigned long long)
- dccp_rsk(req)->dreq_iss);
+ (unsigned long long) dreq->dreq_iss);
goto drop;
}
+ if (dccp_parse_options(sk, dreq, skb))
+ goto drop;
+
child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL);
if (child == NULL)
goto listen_overflow;
- /* FIXME: deal with options */
-
inet_csk_reqsk_queue_unlink(sk, req, prev);
inet_csk_reqsk_queue_removed(sk, req);
inet_csk_reqsk_queue_add(sk, req, child);
@@ -303,9 +305,12 @@ EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack);
void dccp_reqsk_init(struct request_sock *req, struct sk_buff *skb)
{
- inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
- inet_rsk(req)->acked = 0;
- req->rcv_wnd = sysctl_dccp_feat_sequence_window;
+ struct dccp_request_sock *dreq = dccp_rsk(req);
+
+ inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
+ inet_rsk(req)->acked = 0;
+ req->rcv_wnd = sysctl_dccp_feat_sequence_window;
+ dreq->dreq_timestamp_echo = 0;
}
EXPORT_SYMBOL_GPL(dccp_reqsk_init);
diff --git a/net/dccp/options.c b/net/dccp/options.c
index d286cff..d2a84a2 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -46,7 +46,13 @@ static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
return value;
}
-int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
+/**
+ * dccp_parse_options - Parse DCCP options present in @skb
+ * @sk: client|server|listening dccp socket (when @dreq != NULL)
+ * @dreq: request socket to use during connection setup, or NULL
+ */
+int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
+ struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
const struct dccp_hdr *dh = dccp_hdr(skb);
@@ -92,6 +98,20 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
goto out_invalid_option;
}
+ /*
+ * CCID-Specific Options (from RFC 4340, sec. 10.3):
+ *
+ * Option numbers 128 through 191 are for options sent from the
+ * HC-Sender to the HC-Receiver; option numbers 192 through 255
+ * are for options sent from the HC-Receiver to the HC-Sender.
+ *
+ * CCID-specific options are ignored during connection setup, as
+ * negotiation may still be in progress (see RFC 4340, 10.3).
+ *
+ */
+ if (dreq != NULL && opt >= 128)
+ goto ignore_option;
+
switch (opt) {
case DCCPO_PADDING:
break;
@@ -112,6 +132,8 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
case DCCPO_CHANGE_L:
/* fall through */
case DCCPO_CHANGE_R:
+ if (pkt_type == DCCP_PKT_DATA)
+ break;
if (len < 2)
goto out_invalid_option;
rc = dccp_feat_change_recv(sk, opt, *value, value + 1,
@@ -128,7 +150,9 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
case DCCPO_CONFIRM_L:
/* fall through */
case DCCPO_CONFIRM_R:
- if (len < 2)
+ if (pkt_type == DCCP_PKT_DATA)
+ break;
+ if (len < 2) /* FIXME this disallows empty confirm */
goto out_invalid_option;
if (dccp_feat_confirm_recv(sk, opt, *value,
value + 1, len - 1))
@@ -136,7 +160,7 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
break;
case DCCPO_ACK_VECTOR_0:
case DCCPO_ACK_VECTOR_1:
- if (pkt_type == DCCP_PKT_DATA)
+ if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
break;
if (dccp_msk(sk)->dccpms_send_ack_vector &&
@@ -146,15 +170,27 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
case DCCPO_TIMESTAMP:
if (len != 4)
goto out_invalid_option;
-
+ /*
+ * RFC 4340 13.1: "The precise time corresponding to
+ * Timestamp Value zero is not specified". We use
+ * zero to indicate absence of a meaningful timestamp.
+ */
opt_val = get_unaligned((__be32 *)value);
- opt_recv->dccpor_timestamp = ntohl(opt_val);
-
- dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp;
- dp->dccps_timestamp_time = ktime_get_real();
+ if (unlikely(opt_val == 0)) {
+ DCCP_WARN("Timestamp with zero value\n");
+ break;
+ }
+ if (dreq != NULL) {
+ dreq->dreq_timestamp_echo = ntohl(opt_val);
+ dreq->dreq_timestamp_time = dccp_timestamp();
+ } else {
+ opt_recv->dccpor_timestamp =
+ dp->dccps_timestamp_echo = ntohl(opt_val);
+ dp->dccps_timestamp_time = dccp_timestamp();
+ }
dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n",
- dccp_role(sk), opt_recv->dccpor_timestamp,
+ dccp_role(sk), ntohl(opt_val),
(unsigned long long)
DCCP_SKB_CB(skb)->dccpd_ack_seq);
break;
@@ -194,18 +230,17 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
opt_recv->dccpor_elapsed_time = elapsed_time;
break;
case DCCPO_ELAPSED_TIME:
- if (len != 2 && len != 4)
- goto out_invalid_option;
-
- if (pkt_type == DCCP_PKT_DATA)
- continue;
+ if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */
+ break;
if (len == 2) {
__be16 opt_val2 = get_unaligned((__be16 *)value);
elapsed_time = ntohs(opt_val2);
- } else {
+ } else if (len == 4) {
opt_val = get_unaligned((__be32 *)value);
elapsed_time = ntohl(opt_val);
+ } else {
+ goto out_invalid_option;
}
if (elapsed_time > opt_recv->dccpor_elapsed_time)
@@ -214,15 +249,6 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
dccp_role(sk), elapsed_time);
break;
- /*
- * From RFC 4340, sec. 10.3:
- *
- * Option numbers 128 through 191 are for
- * options sent from the HC-Sender to the
- * HC-Receiver; option numbers 192 through 255
- * are for options sent from the HC-Receiver to
- * the HC-Sender.
- */
case 128 ... 191: {
const u16 idx = value - options;
@@ -246,7 +272,7 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
"implemented, ignoring", sk, opt, len);
break;
}
-
+ignore_option:
if (opt != DCCPO_MANDATORY)
mandatory = 0;
}
@@ -382,16 +408,24 @@ int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
-static int dccp_insert_option_timestamp_echo(struct sock *sk,
+static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
+ struct dccp_request_sock *dreq,
struct sk_buff *skb)
{
- struct dccp_sock *dp = dccp_sk(sk);
__be32 tstamp_echo;
- int len, elapsed_time_len;
unsigned char *to;
- const suseconds_t delta = ktime_us_delta(ktime_get_real(),
- dp->dccps_timestamp_time);
- u32 elapsed_time = delta / 10;
+ u32 elapsed_time, elapsed_time_len, len;
+
+ if (dreq != NULL) {
+ elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time;
+ tstamp_echo = htonl(dreq->dreq_timestamp_echo);
+ dreq->dreq_timestamp_echo = 0;
+ } else {
+ elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time;
+ tstamp_echo = htonl(dp->dccps_timestamp_echo);
+ dp->dccps_timestamp_echo = 0;
+ }
+
elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
len = 6 + elapsed_time_len;
@@ -404,7 +438,6 @@ static int dccp_insert_option_timestamp_echo(struct sock *sk,
*to++ = DCCPO_TIMESTAMP_ECHO;
*to++ = len;
- tstamp_echo = htonl(dp->dccps_timestamp_echo);
memcpy(to, &tstamp_echo, 4);
to += 4;
@@ -416,8 +449,6 @@ static int dccp_insert_option_timestamp_echo(struct sock *sk,
memcpy(to, &var32, 4);
}
- dp->dccps_timestamp_echo = 0;
- dp->dccps_timestamp_time = ktime_set(0, 0);
return 0;
}
@@ -510,6 +541,18 @@ static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb)
return 0;
}
+/* The length of all options needs to be a multiple of 4 (5.8) */
+static void dccp_insert_option_padding(struct sk_buff *skb)
+{
+ int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
+
+ if (padding != 0) {
+ padding = 4 - padding;
+ memset(skb_push(skb, padding), 0, padding);
+ DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
+ }
+}
+
int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
@@ -526,10 +569,6 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
dccp_insert_option_ackvec(sk, skb))
return -1;
-
- if (dp->dccps_timestamp_echo != 0 &&
- dccp_insert_option_timestamp_echo(sk, skb))
- return -1;
}
if (dp->dccps_hc_rx_insert_options) {
@@ -553,18 +592,22 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
dccp_insert_option_timestamp(sk, skb))
return -1;
- /* XXX: insert other options when appropriate */
+ if (dp->dccps_timestamp_echo != 0 &&
+ dccp_insert_option_timestamp_echo(dp, NULL, skb))
+ return -1;
+
+ dccp_insert_option_padding(skb);
+ return 0;
+}
- if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) {
- /* The length of all options has to be a multiple of 4 */
- int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
+int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
+{
+ DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
- if (padding != 0) {
- padding = 4 - padding;
- memset(skb_push(skb, padding), 0, padding);
- DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
- }
- }
+ if (dreq->dreq_timestamp_echo != 0 &&
+ dccp_insert_option_timestamp_echo(NULL, dreq, skb))
+ return -1;
+ dccp_insert_option_padding(skb);
return 0;
}
diff --git a/net/dccp/output.c b/net/dccp/output.c
index f495446..3b763db 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -133,15 +133,31 @@ static int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb)
return -ENOBUFS;
}
+/**
+ * dccp_determine_ccmps - Find out about CCID-specfic packet-size limits
+ * We only consider the HC-sender CCID for setting the CCMPS (RFC 4340, 14.),
+ * since the RX CCID is restricted to feedback packets (Acks), which are small
+ * in comparison with the data traffic. A value of 0 means "no current CCMPS".
+ */
+static u32 dccp_determine_ccmps(const struct dccp_sock *dp)
+{
+ const struct ccid *tx_ccid = dp->dccps_hc_tx_ccid;
+
+ if (tx_ccid == NULL || tx_ccid->ccid_ops == NULL)
+ return 0;
+ return tx_ccid->ccid_ops->ccid_ccmps;
+}
+
unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct dccp_sock *dp = dccp_sk(sk);
- int mss_now = (pmtu - icsk->icsk_af_ops->net_header_len -
- sizeof(struct dccp_hdr) - sizeof(struct dccp_hdr_ext));
+ u32 ccmps = dccp_determine_ccmps(dp);
+ int cur_mps = ccmps ? min(pmtu, ccmps) : pmtu;
- /* Now subtract optional transport overhead */
- mss_now -= icsk->icsk_ext_hdr_len;
+ /* Account for header lengths and IPv4/v6 option overhead */
+ cur_mps -= (icsk->icsk_af_ops->net_header_len + icsk->icsk_ext_hdr_len +
+ sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext));
/*
* FIXME: this should come from the CCID infrastructure, where, say,
@@ -151,13 +167,13 @@ unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu)
* make it a multiple of 4
*/
- mss_now -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4;
+ cur_mps -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4;
/* And store cached results */
icsk->icsk_pmtu_cookie = pmtu;
- dp->dccps_mss_cache = mss_now;
+ dp->dccps_mss_cache = cur_mps;
- return mss_now;
+ return cur_mps;
}
EXPORT_SYMBOL_GPL(dccp_sync_mss);
@@ -170,7 +186,7 @@ void dccp_write_space(struct sock *sk)
wake_up_interruptible(sk->sk_sleep);
/* Should agree with poll, otherwise some programs break */
if (sock_writeable(sk))
- sk_wake_async(sk, 2, POLL_OUT);
+ sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
read_unlock(&sk->sk_callback_lock);
}
@@ -303,7 +319,7 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst,
DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE;
DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss;
- if (dccp_insert_options(sk, skb)) {
+ if (dccp_insert_options_rsk(dreq, skb)) {
kfree_skb(skb);
return NULL;
}
@@ -391,7 +407,7 @@ int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code)
* FIXME: what if rebuild_header fails?
* Should we be doing a rebuild_header here?
*/
- int err = inet_sk_rebuild_header(sk);
+ int err = inet_csk(sk)->icsk_af_ops->rebuild_header(sk);
if (err != 0)
return err;
@@ -567,14 +583,27 @@ void dccp_send_close(struct sock *sk, const int active)
/* Reserve space for headers and prepare control bits. */
skb_reserve(skb, sk->sk_prot->max_header);
- DCCP_SKB_CB(skb)->dccpd_type = dp->dccps_role == DCCP_ROLE_CLIENT ?
- DCCP_PKT_CLOSE : DCCP_PKT_CLOSEREQ;
+ if (dp->dccps_role == DCCP_ROLE_SERVER && !dp->dccps_server_timewait)
+ DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSEREQ;
+ else
+ DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSE;
if (active) {
dccp_write_xmit(sk, 1);
dccp_skb_entail(sk, skb);
dccp_transmit_skb(sk, skb_clone(skb, prio));
- /* FIXME do we need a retransmit timer here? */
+ /*
+ * Retransmission timer for active-close: RFC 4340, 8.3 requires
+ * to retransmit the Close/CloseReq until the CLOSING/CLOSEREQ
+ * state can be left. The initial timeout is 2 RTTs.
+ * Since RTT measurement is done by the CCIDs, there is no easy
+ * way to get an RTT sample. The fallback RTT from RFC 4340, 3.4
+ * is too low (200ms); we use a high value to avoid unnecessary
+ * retransmissions when the link RTT is > 0.2 seconds.
+ * FIXME: Let main module sample RTTs and use that instead.
+ */
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ DCCP_TIMEOUT_INIT, DCCP_RTO_MAX);
} else
dccp_transmit_skb(sk, skb);
}
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 7a3bea9..0bed4a6 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -60,8 +60,7 @@ void dccp_set_state(struct sock *sk, const int state)
{
const int oldstate = sk->sk_state;
- dccp_pr_debug("%s(%p) %-10.10s -> %s\n",
- dccp_role(sk), sk,
+ dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk,
dccp_state_name(oldstate), dccp_state_name(state));
WARN_ON(state == oldstate);
@@ -72,7 +71,8 @@ void dccp_set_state(struct sock *sk, const int state)
break;
case DCCP_CLOSED:
- if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN)
+ if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ ||
+ oldstate == DCCP_CLOSING)
DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
sk->sk_prot->unhash(sk);
@@ -93,6 +93,24 @@ void dccp_set_state(struct sock *sk, const int state)
EXPORT_SYMBOL_GPL(dccp_set_state);
+static void dccp_finish_passive_close(struct sock *sk)
+{
+ switch (sk->sk_state) {
+ case DCCP_PASSIVE_CLOSE:
+ /* Node (client or server) has received Close packet. */
+ dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED);
+ dccp_set_state(sk, DCCP_CLOSED);
+ break;
+ case DCCP_PASSIVE_CLOSEREQ:
+ /*
+ * Client received CloseReq. We set the `active' flag so that
+ * dccp_send_close() retransmits the Close as per RFC 4340, 8.3.
+ */
+ dccp_send_close(sk, 1);
+ dccp_set_state(sk, DCCP_CLOSING);
+ }
+}
+
void dccp_done(struct sock *sk)
{
dccp_set_state(sk, DCCP_CLOSED);
@@ -134,14 +152,17 @@ EXPORT_SYMBOL_GPL(dccp_packet_name);
const char *dccp_state_name(const int state)
{
static char *dccp_state_names[] = {
- [DCCP_OPEN] = "OPEN",
- [DCCP_REQUESTING] = "REQUESTING",
- [DCCP_PARTOPEN] = "PARTOPEN",
- [DCCP_LISTEN] = "LISTEN",
- [DCCP_RESPOND] = "RESPOND",
- [DCCP_CLOSING] = "CLOSING",
- [DCCP_TIME_WAIT] = "TIME_WAIT",
- [DCCP_CLOSED] = "CLOSED",
+ [DCCP_OPEN] = "OPEN",
+ [DCCP_REQUESTING] = "REQUESTING",
+ [DCCP_PARTOPEN] = "PARTOPEN",
+ [DCCP_LISTEN] = "LISTEN",
+ [DCCP_RESPOND] = "RESPOND",
+ [DCCP_CLOSING] = "CLOSING",
+ [DCCP_ACTIVE_CLOSEREQ] = "CLOSEREQ",
+ [DCCP_PASSIVE_CLOSE] = "PASSIVE_CLOSE",
+ [DCCP_PASSIVE_CLOSEREQ] = "PASSIVE_CLOSEREQ",
+ [DCCP_TIME_WAIT] = "TIME_WAIT",
+ [DCCP_CLOSED] = "CLOSED",
};
if (state >= DCCP_MAX_STATES)
@@ -174,6 +195,19 @@ int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
dccp_minisock_init(&dp->dccps_minisock);
+ icsk->icsk_rto = DCCP_TIMEOUT_INIT;
+ icsk->icsk_syn_retries = sysctl_dccp_request_retries;
+ sk->sk_state = DCCP_CLOSED;
+ sk->sk_write_space = dccp_write_space;
+ icsk->icsk_sync_mss = dccp_sync_mss;
+ dp->dccps_mss_cache = 536;
+ dp->dccps_rate_last = jiffies;
+ dp->dccps_role = DCCP_ROLE_UNDEFINED;
+ dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT;
+ dp->dccps_l_ack_ratio = dp->dccps_r_ack_ratio = 1;
+
+ dccp_init_xmit_timers(sk);
+
/*
* FIXME: We're hardcoding the CCID, and doing this at this point makes
* the listening (master) sock get CCID control blocks, which is not
@@ -213,18 +247,6 @@ int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
INIT_LIST_HEAD(&dmsk->dccpms_conf);
}
- dccp_init_xmit_timers(sk);
- icsk->icsk_rto = DCCP_TIMEOUT_INIT;
- icsk->icsk_syn_retries = sysctl_dccp_request_retries;
- sk->sk_state = DCCP_CLOSED;
- sk->sk_write_space = dccp_write_space;
- icsk->icsk_sync_mss = dccp_sync_mss;
- dp->dccps_mss_cache = 536;
- dp->dccps_rate_last = jiffies;
- dp->dccps_role = DCCP_ROLE_UNDEFINED;
- dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT;
- dp->dccps_l_ack_ratio = dp->dccps_r_ack_ratio = 1;
-
return 0;
}
@@ -275,6 +297,12 @@ static inline int dccp_listen_start(struct sock *sk, int backlog)
return inet_csk_listen_start(sk, backlog);
}
+static inline int dccp_need_reset(int state)
+{
+ return state != DCCP_CLOSED && state != DCCP_LISTEN &&
+ state != DCCP_REQUESTING;
+}
+
int dccp_disconnect(struct sock *sk, int flags)
{
struct inet_connection_sock *icsk = inet_csk(sk);
@@ -285,10 +313,15 @@ int dccp_disconnect(struct sock *sk, int flags)
if (old_state != DCCP_CLOSED)
dccp_set_state(sk, DCCP_CLOSED);
- /* ABORT function of RFC793 */
+ /*
+ * This corresponds to the ABORT function of RFC793, sec. 3.8
+ * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted".
+ */
if (old_state == DCCP_LISTEN) {
inet_csk_listen_stop(sk);
- /* FIXME: do the active reset thing */
+ } else if (dccp_need_reset(old_state)) {
+ dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
+ sk->sk_err = ECONNRESET;
} else if (old_state == DCCP_REQUESTING)
sk->sk_err = ECONNRESET;
@@ -518,6 +551,12 @@ static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
(struct dccp_so_feat __user *)
optval);
break;
+ case DCCP_SOCKOPT_SERVER_TIMEWAIT:
+ if (dp->dccps_role != DCCP_ROLE_SERVER)
+ err = -EOPNOTSUPP;
+ else
+ dp->dccps_server_timewait = (val != 0);
+ break;
case DCCP_SOCKOPT_SEND_CSCOV: /* sender side, RFC 4340, sec. 9.2 */
if (val < 0 || val > 15)
err = -EINVAL;
@@ -618,15 +657,15 @@ static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
(__be32 __user *)optval, optlen);
case DCCP_SOCKOPT_GET_CUR_MPS:
val = dp->dccps_mss_cache;
- len = sizeof(val);
+ break;
+ case DCCP_SOCKOPT_SERVER_TIMEWAIT:
+ val = dp->dccps_server_timewait;
break;
case DCCP_SOCKOPT_SEND_CSCOV:
val = dp->dccps_pcslen;
- len = sizeof(val);
break;
case DCCP_SOCKOPT_RECV_CSCOV:
val = dp->dccps_pcrlen;
- len = sizeof(val);
break;
case 128 ... 191:
return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
@@ -638,6 +677,7 @@ static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
return -ENOPROTOOPT;
}
+ len = sizeof(val);
if (put_user(len, optlen) || copy_to_user(optval, &val, len))
return -EFAULT;
@@ -748,19 +788,26 @@ int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
dh = dccp_hdr(skb);
- if (dh->dccph_type == DCCP_PKT_DATA ||
- dh->dccph_type == DCCP_PKT_DATAACK)
+ switch (dh->dccph_type) {
+ case DCCP_PKT_DATA:
+ case DCCP_PKT_DATAACK:
goto found_ok_skb;
- if (dh->dccph_type == DCCP_PKT_RESET ||
- dh->dccph_type == DCCP_PKT_CLOSE) {
- dccp_pr_debug("found fin ok!\n");
+ case DCCP_PKT_CLOSE:
+ case DCCP_PKT_CLOSEREQ:
+ if (!(flags & MSG_PEEK))
+ dccp_finish_passive_close(sk);
+ /* fall through */
+ case DCCP_PKT_RESET:
+ dccp_pr_debug("found fin (%s) ok!\n",
+ dccp_packet_name(dh->dccph_type));
len = 0;
goto found_fin_ok;
+ default:
+ dccp_pr_debug("packet_type=%s\n",
+ dccp_packet_name(dh->dccph_type));
+ sk_eat_skb(sk, skb, 0);
}
- dccp_pr_debug("packet_type=%s\n",
- dccp_packet_name(dh->dccph_type));
- sk_eat_skb(sk, skb, 0);
verify_sock_status:
if (sock_flag(sk, SOCK_DONE)) {
len = 0;
@@ -862,34 +909,38 @@ out:
EXPORT_SYMBOL_GPL(inet_dccp_listen);
-static const unsigned char dccp_new_state[] = {
- /* current state: new state: action: */
- [0] = DCCP_CLOSED,
- [DCCP_OPEN] = DCCP_CLOSING | DCCP_ACTION_FIN,
- [DCCP_REQUESTING] = DCCP_CLOSED,
- [DCCP_PARTOPEN] = DCCP_CLOSING | DCCP_ACTION_FIN,
- [DCCP_LISTEN] = DCCP_CLOSED,
- [DCCP_RESPOND] = DCCP_CLOSED,
- [DCCP_CLOSING] = DCCP_CLOSED,
- [DCCP_TIME_WAIT] = DCCP_CLOSED,
- [DCCP_CLOSED] = DCCP_CLOSED,
-};
-
-static int dccp_close_state(struct sock *sk)
+static void dccp_terminate_connection(struct sock *sk)
{
- const int next = dccp_new_state[sk->sk_state];
- const int ns = next & DCCP_STATE_MASK;
+ u8 next_state = DCCP_CLOSED;
- if (ns != sk->sk_state)
- dccp_set_state(sk, ns);
+ switch (sk->sk_state) {
+ case DCCP_PASSIVE_CLOSE:
+ case DCCP_PASSIVE_CLOSEREQ:
+ dccp_finish_passive_close(sk);
+ break;
+ case DCCP_PARTOPEN:
+ dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk);
+ inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
+ /* fall through */
+ case DCCP_OPEN:
+ dccp_send_close(sk, 1);
- return next & DCCP_ACTION_FIN;
+ if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER &&
+ !dccp_sk(sk)->dccps_server_timewait)
+ next_state = DCCP_ACTIVE_CLOSEREQ;
+ else
+ next_state = DCCP_CLOSING;
+ /* fall through */
+ default:
+ dccp_set_state(sk, next_state);
+ }
}
void dccp_close(struct sock *sk, long timeout)
{
struct dccp_sock *dp = dccp_sk(sk);
struct sk_buff *skb;
+ u32 data_was_unread = 0;
int state;
lock_sock(sk);
@@ -912,16 +963,21 @@ void dccp_close(struct sock *sk, long timeout)
* descriptor close, not protocol-sourced closes, because the
*reader process may not have drained the data yet!
*/
- /* FIXME: check for unread data */
while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+ data_was_unread += skb->len;
__kfree_skb(skb);
}
- if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
+ if (data_was_unread) {
+ /* Unread data was tossed, send an appropriate Reset Code */
+ DCCP_WARN("DCCP: ABORT -- %u bytes unread\n", data_was_unread);
+ dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
+ dccp_set_state(sk, DCCP_CLOSED);
+ } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
/* Check zero linger _after_ checking for unread data. */
sk->sk_prot->disconnect(sk, 0);
- } else if (dccp_close_state(sk)) {
- dccp_send_close(sk, 1);
+ } else if (sk->sk_state != DCCP_CLOSED) {
+ dccp_terminate_connection(sk);
}
sk_stream_wait_close(sk, timeout);
@@ -948,24 +1004,6 @@ adjudge_to_death:
if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED)
goto out;
- /*
- * The last release_sock may have processed the CLOSE or RESET
- * packet moving sock to CLOSED state, if not we have to fire
- * the CLOSE/CLOSEREQ retransmission timer, see "8.3. Termination"
- * in draft-ietf-dccp-spec-11. -acme
- */
- if (sk->sk_state == DCCP_CLOSING) {
- /* FIXME: should start at 2 * RTT */
- /* Timer for repeating the CLOSE/CLOSEREQ until an answer. */
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
- inet_csk(sk)->icsk_rto,
- DCCP_RTO_MAX);
-#if 0
- /* Yeah, we should use sk->sk_prot->orphan_count, etc */
- dccp_set_state(sk, DCCP_CLOSED);
-#endif
- }
-
if (sk->sk_state == DCCP_CLOSED)
inet_csk_destroy_sock(sk);
@@ -981,7 +1019,7 @@ EXPORT_SYMBOL_GPL(dccp_close);
void dccp_shutdown(struct sock *sk, int how)
{
- dccp_pr_debug("entry\n");
+ dccp_pr_debug("called shutdown(%x)\n", how);
}
EXPORT_SYMBOL_GPL(dccp_shutdown);
diff --git a/net/dccp/sysctl.c b/net/dccp/sysctl.c
index c62c050..2129599 100644
--- a/net/dccp/sysctl.c
+++ b/net/dccp/sysctl.c
@@ -100,41 +100,19 @@ static struct ctl_table dccp_default_table[] = {
{ .ctl_name = 0, }
};
-static struct ctl_table dccp_table[] = {
- {
- .ctl_name = NET_DCCP_DEFAULT,
- .procname = "default",
- .mode = 0555,
- .child = dccp_default_table,
- },
- { .ctl_name = 0, },
-};
-
-static struct ctl_table dccp_dir_table[] = {
- {
- .ctl_name = NET_DCCP,
- .procname = "dccp",
- .mode = 0555,
- .child = dccp_table,
- },
- { .ctl_name = 0, },
-};
-
-static struct ctl_table dccp_root_table[] = {
- {
- .ctl_name = CTL_NET,
- .procname = "net",
- .mode = 0555,
- .child = dccp_dir_table,
- },
- { .ctl_name = 0, },
+static struct ctl_path dccp_path[] = {
+ { .procname = "net", .ctl_name = CTL_NET, },
+ { .procname = "dccp", .ctl_name = NET_DCCP, },
+ { .procname = "default", .ctl_name = NET_DCCP_DEFAULT, },
+ { }
};
static struct ctl_table_header *dccp_table_header;
int __init dccp_sysctl_init(void)
{
- dccp_table_header = register_sysctl_table(dccp_root_table);
+ dccp_table_header = register_sysctl_paths(dccp_path,
+ dccp_default_table);
return dccp_table_header != NULL ? 0 : -ENOMEM;
}
diff --git a/net/dccp/timer.c b/net/dccp/timer.c
index 3af0673..8703a79 100644
--- a/net/dccp/timer.c
+++ b/net/dccp/timer.c
@@ -280,9 +280,8 @@ static void dccp_init_write_xmit_timer(struct sock *sk)
{
struct dccp_sock *dp = dccp_sk(sk);
- init_timer(&dp->dccps_xmit_timer);
- dp->dccps_xmit_timer.data = (unsigned long)sk;
- dp->dccps_xmit_timer.function = dccp_write_xmit_timer;
+ setup_timer(&dp->dccps_xmit_timer, dccp_write_xmit_timer,
+ (unsigned long)sk);
}
void dccp_init_xmit_timers(struct sock *sk)
generated by cgit v0.10.2 at 2024-11-09 11:48:18 (GMT)