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author | Andreas Baumann <mail@andreasbaumann.cc> | 2015-01-03 12:04:58 +0100 |
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committer | Andreas Baumann <mail@andreasbaumann.cc> | 2015-01-03 12:04:58 +0100 |
commit | 008d0be72b2f160382c6e880765e96b64a050c65 (patch) | |
tree | 36f48a98a3815a408e2ce1693dd182af90f80305 /release/src/linux/linux/net/ipv4/netfilter/ipt_mport.c | |
parent | 611becfb8726c60cb060368541ad98191d4532f5 (diff) | |
download | tomato-008d0be72b2f160382c6e880765e96b64a050c65.tar.gz tomato-008d0be72b2f160382c6e880765e96b64a050c65.tar.bz2 |
imported original firmware WRT54GL_v4.30.11_11_US
Diffstat (limited to 'release/src/linux/linux/net/ipv4/netfilter/ipt_mport.c')
-rw-r--r-- | release/src/linux/linux/net/ipv4/netfilter/ipt_mport.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/release/src/linux/linux/net/ipv4/netfilter/ipt_mport.c b/release/src/linux/linux/net/ipv4/netfilter/ipt_mport.c new file mode 100644 index 00000000..ca99b764 --- /dev/null +++ b/release/src/linux/linux/net/ipv4/netfilter/ipt_mport.c @@ -0,0 +1,108 @@ +/* Kernel module to match one of a list of TCP/UDP ports: ports are in + the same place so we can treat them as equal. */ +#include <linux/module.h> +#include <linux/types.h> +#include <linux/udp.h> +#include <linux/skbuff.h> + +#include <linux/netfilter_ipv4/ipt_mport.h> +#include <linux/netfilter_ipv4/ip_tables.h> + +MODULE_LICENSE("GPL"); + +#define duprintf(format, args...) + +/* Returns 1 if the port is matched by the test, 0 otherwise. */ +static inline int +ports_match(const struct ipt_mport *minfo, u_int16_t src, u_int16_t dst) +{ + unsigned int i; + unsigned int m; + u_int16_t pflags = minfo->pflags; + for (i=0, m=1; i<IPT_MULTI_PORTS; i++, m<<=1) { + u_int16_t s, e; + + if (pflags & m + && minfo->ports[i] == 65535) + return 0; + + s = minfo->ports[i]; + + if (pflags & m) { + e = minfo->ports[++i]; + m <<= 1; + } else + e = s; + + if (minfo->flags & IPT_MPORT_SOURCE + && src >= s && src <= e) + return 1; + + if (minfo->flags & IPT_MPORT_DESTINATION + && dst >= s && dst <= e) + return 1; + } + + return 0; +} + +static int +match(const struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + const void *matchinfo, + int offset, + const void *hdr, + u_int16_t datalen, + int *hotdrop) +{ + const struct udphdr *udp = hdr; + const struct ipt_mport *minfo = matchinfo; + + /* Must be big enough to read ports. */ + if (offset == 0 && datalen < sizeof(struct udphdr)) { + /* We've been asked to examine this packet, and we + can't. Hence, no choice but to drop. */ + duprintf("ipt_mport:" + " Dropping evil offset=0 tinygram.\n"); + *hotdrop = 1; + return 0; + } + + /* Must not be a fragment. */ + return !offset + && ports_match(minfo, ntohs(udp->source), ntohs(udp->dest)); +} + +/* Called when user tries to insert an entry of this type. */ +static int +checkentry(const char *tablename, + const struct ipt_ip *ip, + void *matchinfo, + unsigned int matchsize, + unsigned int hook_mask) +{ + if (matchsize != IPT_ALIGN(sizeof(struct ipt_mport))) + return 0; + + /* Must specify proto == TCP/UDP, no unknown flags or bad count */ + return (ip->proto == IPPROTO_TCP || ip->proto == IPPROTO_UDP) + && !(ip->invflags & IPT_INV_PROTO) + && matchsize == IPT_ALIGN(sizeof(struct ipt_mport)); +} + +static struct ipt_match mport_match += { { NULL, NULL }, "mport", &match, &checkentry, NULL, THIS_MODULE }; + +static int __init init(void) +{ + return ipt_register_match(&mport_match); +} + +static void __exit fini(void) +{ + ipt_unregister_match(&mport_match); +} + +module_init(init); +module_exit(fini); |