diff options
Diffstat (limited to 'net/ipv4')
-rw-r--r-- | net/ipv4/netfilter/ip_nat_core.c | 12 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_nat_proto_tcp.c | 5 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_nat_proto_udp.c | 5 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_nat_rule.c | 4 | ||||
-rw-r--r-- | net/ipv4/netfilter/nf_nat_core.c | 12 | ||||
-rw-r--r-- | net/ipv4/netfilter/nf_nat_proto_tcp.c | 4 | ||||
-rw-r--r-- | net/ipv4/netfilter/nf_nat_proto_udp.c | 4 | ||||
-rw-r--r-- | net/ipv4/netfilter/nf_nat_rule.c | 4 |
8 files changed, 46 insertions, 4 deletions
diff --git a/net/ipv4/netfilter/ip_nat_core.c b/net/ipv4/netfilter/ip_nat_core.c index 9d1a517..5e08c2b 100644 --- a/net/ipv4/netfilter/ip_nat_core.c +++ b/net/ipv4/netfilter/ip_nat_core.c @@ -246,8 +246,9 @@ get_unique_tuple(struct ip_conntrack_tuple *tuple, if (maniptype == IP_NAT_MANIP_SRC) { if (find_appropriate_src(orig_tuple, tuple, range)) { DEBUGP("get_unique_tuple: Found current src map\n"); - if (!ip_nat_used_tuple(tuple, conntrack)) - return; + if (!(range->flags & IP_NAT_RANGE_PROTO_RANDOM)) + if (!ip_nat_used_tuple(tuple, conntrack)) + return; } } @@ -261,6 +262,13 @@ get_unique_tuple(struct ip_conntrack_tuple *tuple, proto = ip_nat_proto_find_get(orig_tuple->dst.protonum); + /* Change protocol info to have some randomization */ + if (range->flags & IP_NAT_RANGE_PROTO_RANDOM) { + proto->unique_tuple(tuple, range, maniptype, conntrack); + ip_nat_proto_put(proto); + return; + } + /* Only bother mapping if it's not already in range and unique */ if ((!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED) || proto->in_range(tuple, maniptype, &range->min, &range->max)) diff --git a/net/ipv4/netfilter/ip_nat_proto_tcp.c b/net/ipv4/netfilter/ip_nat_proto_tcp.c index b586d18..14ff24f 100644 --- a/net/ipv4/netfilter/ip_nat_proto_tcp.c +++ b/net/ipv4/netfilter/ip_nat_proto_tcp.c @@ -8,6 +8,7 @@ #include <linux/types.h> #include <linux/init.h> +#include <linux/random.h> #include <linux/netfilter.h> #include <linux/ip.h> #include <linux/tcp.h> @@ -75,6 +76,10 @@ tcp_unique_tuple(struct ip_conntrack_tuple *tuple, range_size = ntohs(range->max.tcp.port) - min + 1; } + /* Start from random port to avoid prediction */ + if (range->flags & IP_NAT_RANGE_PROTO_RANDOM) + port = net_random(); + for (i = 0; i < range_size; i++, port++) { *portptr = htons(min + port % range_size); if (!ip_nat_used_tuple(tuple, conntrack)) { diff --git a/net/ipv4/netfilter/ip_nat_proto_udp.c b/net/ipv4/netfilter/ip_nat_proto_udp.c index 5ced087..dfd5216 100644 --- a/net/ipv4/netfilter/ip_nat_proto_udp.c +++ b/net/ipv4/netfilter/ip_nat_proto_udp.c @@ -8,6 +8,7 @@ #include <linux/types.h> #include <linux/init.h> +#include <linux/random.h> #include <linux/netfilter.h> #include <linux/ip.h> #include <linux/udp.h> @@ -74,6 +75,10 @@ udp_unique_tuple(struct ip_conntrack_tuple *tuple, range_size = ntohs(range->max.udp.port) - min + 1; } + /* Start from random port to avoid prediction */ + if (range->flags & IP_NAT_RANGE_PROTO_RANDOM) + port = net_random(); + for (i = 0; i < range_size; i++, port++) { *portptr = htons(min + port % range_size); if (!ip_nat_used_tuple(tuple, conntrack)) diff --git a/net/ipv4/netfilter/ip_nat_rule.c b/net/ipv4/netfilter/ip_nat_rule.c index a176aa3..6ebaad3 100644 --- a/net/ipv4/netfilter/ip_nat_rule.c +++ b/net/ipv4/netfilter/ip_nat_rule.c @@ -193,6 +193,10 @@ static int ipt_dnat_checkentry(const char *tablename, printk("DNAT: multiple ranges no longer supported\n"); return 0; } + if (mr->range[0].flags & IP_NAT_RANGE_PROTO_RANDOM) { + printk("DNAT: port randomization not supported\n"); + return 0; + } return 1; } diff --git a/net/ipv4/netfilter/nf_nat_core.c b/net/ipv4/netfilter/nf_nat_core.c index 86a9227..998b255 100644 --- a/net/ipv4/netfilter/nf_nat_core.c +++ b/net/ipv4/netfilter/nf_nat_core.c @@ -254,8 +254,9 @@ get_unique_tuple(struct nf_conntrack_tuple *tuple, if (maniptype == IP_NAT_MANIP_SRC) { if (find_appropriate_src(orig_tuple, tuple, range)) { DEBUGP("get_unique_tuple: Found current src map\n"); - if (!nf_nat_used_tuple(tuple, ct)) - return; + if (!(range->flags & IP_NAT_RANGE_PROTO_RANDOM)) + if (!nf_nat_used_tuple(tuple, ct)) + return; } } @@ -269,6 +270,13 @@ get_unique_tuple(struct nf_conntrack_tuple *tuple, proto = nf_nat_proto_find_get(orig_tuple->dst.protonum); + /* Change protocol info to have some randomization */ + if (range->flags & IP_NAT_RANGE_PROTO_RANDOM) { + proto->unique_tuple(tuple, range, maniptype, ct); + nf_nat_proto_put(proto); + return; + } + /* Only bother mapping if it's not already in range and unique */ if ((!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED) || proto->in_range(tuple, maniptype, &range->min, &range->max)) && diff --git a/net/ipv4/netfilter/nf_nat_proto_tcp.c b/net/ipv4/netfilter/nf_nat_proto_tcp.c index 7e26a7e..439164c 100644 --- a/net/ipv4/netfilter/nf_nat_proto_tcp.c +++ b/net/ipv4/netfilter/nf_nat_proto_tcp.c @@ -8,6 +8,7 @@ #include <linux/types.h> #include <linux/init.h> +#include <linux/random.h> #include <linux/ip.h> #include <linux/tcp.h> @@ -75,6 +76,9 @@ tcp_unique_tuple(struct nf_conntrack_tuple *tuple, range_size = ntohs(range->max.tcp.port) - min + 1; } + if (range->flags & IP_NAT_RANGE_PROTO_RANDOM) + port = net_random(); + for (i = 0; i < range_size; i++, port++) { *portptr = htons(min + port % range_size); if (!nf_nat_used_tuple(tuple, ct)) diff --git a/net/ipv4/netfilter/nf_nat_proto_udp.c b/net/ipv4/netfilter/nf_nat_proto_udp.c index ab0ce4c..8cae6e0 100644 --- a/net/ipv4/netfilter/nf_nat_proto_udp.c +++ b/net/ipv4/netfilter/nf_nat_proto_udp.c @@ -8,6 +8,7 @@ #include <linux/types.h> #include <linux/init.h> +#include <linux/random.h> #include <linux/ip.h> #include <linux/udp.h> @@ -73,6 +74,9 @@ udp_unique_tuple(struct nf_conntrack_tuple *tuple, range_size = ntohs(range->max.udp.port) - min + 1; } + if (range->flags & IP_NAT_RANGE_PROTO_RANDOM) + port = net_random(); + for (i = 0; i < range_size; i++, port++) { *portptr = htons(min + port % range_size); if (!nf_nat_used_tuple(tuple, ct)) diff --git a/net/ipv4/netfilter/nf_nat_rule.c b/net/ipv4/netfilter/nf_nat_rule.c index b868ee0..3745efe 100644 --- a/net/ipv4/netfilter/nf_nat_rule.c +++ b/net/ipv4/netfilter/nf_nat_rule.c @@ -226,6 +226,10 @@ static int ipt_dnat_checkentry(const char *tablename, printk("DNAT: multiple ranges no longer supported\n"); return 0; } + if (mr->range[0].flags & IP_NAT_RANGE_PROTO_RANDOM) { + printk("DNAT: port randomization not supported\n"); + return 0; + } return 1; } |