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-rw-r--r--net/ipv6/exthdrs_core.c124
-rw-r--r--net/ipv6/netfilter/ip6_tables.c103
2 files changed, 124 insertions, 103 deletions
diff --git a/net/ipv6/exthdrs_core.c b/net/ipv6/exthdrs_core.c
index e7d756e..c5e83fa 100644
--- a/net/ipv6/exthdrs_core.c
+++ b/net/ipv6/exthdrs_core.c
@@ -155,3 +155,127 @@ int ipv6_find_tlv(struct sk_buff *skb, int offset, int type)
return -1;
}
EXPORT_SYMBOL_GPL(ipv6_find_tlv);
+
+/*
+ * find the offset to specified header or the protocol number of last header
+ * if target < 0. "last header" is transport protocol header, ESP, or
+ * "No next header".
+ *
+ * Note that *offset is used as input/output parameter. an if it is not zero,
+ * then it must be a valid offset to an inner IPv6 header. This can be used
+ * to explore inner IPv6 header, eg. ICMPv6 error messages.
+ *
+ * If target header is found, its offset is set in *offset and return protocol
+ * number. Otherwise, return -1.
+ *
+ * If the first fragment doesn't contain the final protocol header or
+ * NEXTHDR_NONE it is considered invalid.
+ *
+ * Note that non-1st fragment is special case that "the protocol number
+ * of last header" is "next header" field in Fragment header. In this case,
+ * *offset is meaningless and fragment offset is stored in *fragoff if fragoff
+ * isn't NULL.
+ *
+ * if flags is not NULL and it's a fragment, then the frag flag
+ * IP6_FH_F_FRAG will be set. If it's an AH header, the
+ * IP6_FH_F_AUTH flag is set and target < 0, then this function will
+ * stop at the AH header. If IP6_FH_F_SKIP_RH flag was passed, then this
+ * function will skip all those routing headers, where segements_left was 0.
+ */
+int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
+ int target, unsigned short *fragoff, int *flags)
+{
+ unsigned int start = skb_network_offset(skb) + sizeof(struct ipv6hdr);
+ u8 nexthdr = ipv6_hdr(skb)->nexthdr;
+ unsigned int len;
+ bool found;
+
+ if (fragoff)
+ *fragoff = 0;
+
+ if (*offset) {
+ struct ipv6hdr _ip6, *ip6;
+
+ ip6 = skb_header_pointer(skb, *offset, sizeof(_ip6), &_ip6);
+ if (!ip6 || (ip6->version != 6)) {
+ printk(KERN_ERR "IPv6 header not found\n");
+ return -EBADMSG;
+ }
+ start = *offset + sizeof(struct ipv6hdr);
+ nexthdr = ip6->nexthdr;
+ }
+ len = skb->len - start;
+
+ do {
+ struct ipv6_opt_hdr _hdr, *hp;
+ unsigned int hdrlen;
+ found = (nexthdr == target);
+
+ if ((!ipv6_ext_hdr(nexthdr)) || nexthdr == NEXTHDR_NONE) {
+ if (target < 0)
+ break;
+ return -ENOENT;
+ }
+
+ hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr);
+ if (hp == NULL)
+ return -EBADMSG;
+
+ if (nexthdr == NEXTHDR_ROUTING) {
+ struct ipv6_rt_hdr _rh, *rh;
+
+ rh = skb_header_pointer(skb, start, sizeof(_rh),
+ &_rh);
+ if (rh == NULL)
+ return -EBADMSG;
+
+ if (flags && (*flags & IP6_FH_F_SKIP_RH) &&
+ rh->segments_left == 0)
+ found = false;
+ }
+
+ if (nexthdr == NEXTHDR_FRAGMENT) {
+ unsigned short _frag_off;
+ __be16 *fp;
+
+ if (flags) /* Indicate that this is a fragment */
+ *flags |= IP6_FH_F_FRAG;
+ fp = skb_header_pointer(skb,
+ start+offsetof(struct frag_hdr,
+ frag_off),
+ sizeof(_frag_off),
+ &_frag_off);
+ if (fp == NULL)
+ return -EBADMSG;
+
+ _frag_off = ntohs(*fp) & ~0x7;
+ if (_frag_off) {
+ if (target < 0 &&
+ ((!ipv6_ext_hdr(hp->nexthdr)) ||
+ hp->nexthdr == NEXTHDR_NONE)) {
+ if (fragoff)
+ *fragoff = _frag_off;
+ return hp->nexthdr;
+ }
+ return -ENOENT;
+ }
+ hdrlen = 8;
+ } else if (nexthdr == NEXTHDR_AUTH) {
+ if (flags && (*flags & IP6_FH_F_AUTH) && (target < 0))
+ break;
+ hdrlen = (hp->hdrlen + 2) << 2;
+ } else
+ hdrlen = ipv6_optlen(hp);
+
+ if (!found) {
+ nexthdr = hp->nexthdr;
+ len -= hdrlen;
+ start += hdrlen;
+ }
+ } while (!found);
+
+ *offset = start;
+ return nexthdr;
+}
+EXPORT_SYMBOL(ipv6_find_hdr);
+
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 74cadd0..125a90d 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -2271,112 +2271,9 @@ static void __exit ip6_tables_fini(void)
unregister_pernet_subsys(&ip6_tables_net_ops);
}
-/*
- * find the offset to specified header or the protocol number of last header
- * if target < 0. "last header" is transport protocol header, ESP, or
- * "No next header".
- *
- * Note that *offset is used as input/output parameter. an if it is not zero,
- * then it must be a valid offset to an inner IPv6 header. This can be used
- * to explore inner IPv6 header, eg. ICMPv6 error messages.
- *
- * If target header is found, its offset is set in *offset and return protocol
- * number. Otherwise, return -1.
- *
- * If the first fragment doesn't contain the final protocol header or
- * NEXTHDR_NONE it is considered invalid.
- *
- * Note that non-1st fragment is special case that "the protocol number
- * of last header" is "next header" field in Fragment header. In this case,
- * *offset is meaningless and fragment offset is stored in *fragoff if fragoff
- * isn't NULL.
- *
- * if flags is not NULL and it's a fragment, then the frag flag IP6T_FH_F_FRAG
- * will be set. If it's an AH header, the IP6T_FH_F_AUTH flag is set and
- * target < 0, then this function will stop at the AH header.
- */
-int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
- int target, unsigned short *fragoff, int *flags)
-{
- unsigned int start = skb_network_offset(skb) + sizeof(struct ipv6hdr);
- u8 nexthdr = ipv6_hdr(skb)->nexthdr;
- unsigned int len;
-
- if (fragoff)
- *fragoff = 0;
-
- if (*offset) {
- struct ipv6hdr _ip6, *ip6;
-
- ip6 = skb_header_pointer(skb, *offset, sizeof(_ip6), &_ip6);
- if (!ip6 || (ip6->version != 6)) {
- printk(KERN_ERR "IPv6 header not found\n");
- return -EBADMSG;
- }
- start = *offset + sizeof(struct ipv6hdr);
- nexthdr = ip6->nexthdr;
- }
- len = skb->len - start;
-
- while (nexthdr != target) {
- struct ipv6_opt_hdr _hdr, *hp;
- unsigned int hdrlen;
-
- if ((!ipv6_ext_hdr(nexthdr)) || nexthdr == NEXTHDR_NONE) {
- if (target < 0)
- break;
- return -ENOENT;
- }
-
- hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr);
- if (hp == NULL)
- return -EBADMSG;
- if (nexthdr == NEXTHDR_FRAGMENT) {
- unsigned short _frag_off;
- __be16 *fp;
-
- if (flags) /* Indicate that this is a fragment */
- *flags |= IP6T_FH_F_FRAG;
- fp = skb_header_pointer(skb,
- start+offsetof(struct frag_hdr,
- frag_off),
- sizeof(_frag_off),
- &_frag_off);
- if (fp == NULL)
- return -EBADMSG;
-
- _frag_off = ntohs(*fp) & ~0x7;
- if (_frag_off) {
- if (target < 0 &&
- ((!ipv6_ext_hdr(hp->nexthdr)) ||
- hp->nexthdr == NEXTHDR_NONE)) {
- if (fragoff)
- *fragoff = _frag_off;
- return hp->nexthdr;
- }
- return -ENOENT;
- }
- hdrlen = 8;
- } else if (nexthdr == NEXTHDR_AUTH) {
- if (flags && (*flags & IP6T_FH_F_AUTH) && (target < 0))
- break;
- hdrlen = (hp->hdrlen + 2) << 2;
- } else
- hdrlen = ipv6_optlen(hp);
-
- nexthdr = hp->nexthdr;
- len -= hdrlen;
- start += hdrlen;
- }
-
- *offset = start;
- return nexthdr;
-}
-
EXPORT_SYMBOL(ip6t_register_table);
EXPORT_SYMBOL(ip6t_unregister_table);
EXPORT_SYMBOL(ip6t_do_table);
-EXPORT_SYMBOL(ipv6_find_hdr);
module_init(ip6_tables_init);
module_exit(ip6_tables_fini);
generated by cgit v0.10.2 at 2024-11-11 12:00:17 (GMT)