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authorAndreas Baumann <mail@andreasbaumann.cc>2015-01-03 12:04:58 +0100
committerAndreas Baumann <mail@andreasbaumann.cc>2015-01-03 12:04:58 +0100
commit008d0be72b2f160382c6e880765e96b64a050c65 (patch)
tree36f48a98a3815a408e2ce1693dd182af90f80305 /release/src/linux/linux/net/ipv4/netfilter/ipt_ah.c
parent611becfb8726c60cb060368541ad98191d4532f5 (diff)
downloadtomato-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_ah.c')
-rw-r--r--release/src/linux/linux/net/ipv4/netfilter/ipt_ah.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/release/src/linux/linux/net/ipv4/netfilter/ipt_ah.c b/release/src/linux/linux/net/ipv4/netfilter/ipt_ah.c
new file mode 100644
index 00000000..fb17e9b2
--- /dev/null
+++ b/release/src/linux/linux/net/ipv4/netfilter/ipt_ah.c
@@ -0,0 +1,105 @@
+/* Kernel module to match AH parameters. */
+#include <linux/module.h>
+#include <linux/skbuff.h>
+
+#include <linux/netfilter_ipv4/ipt_ah.h>
+#include <linux/netfilter_ipv4/ip_tables.h>
+
+EXPORT_NO_SYMBOLS;
+MODULE_LICENSE("GPL");
+
+#ifdef DEBUG_CONNTRACK
+#define duprintf(format, args...) printk(format , ## args)
+#else
+#define duprintf(format, args...)
+#endif
+
+struct ahhdr {
+ __u32 spi;
+};
+
+/* Returns 1 if the spi is matched by the range, 0 otherwise */
+static inline int
+spi_match(u_int32_t min, u_int32_t max, u_int32_t spi, int invert)
+{
+ int r=0;
+ duprintf("ah spi_match:%c 0x%x <= 0x%x <= 0x%x",invert? '!':' ',
+ min,spi,max);
+ r=(spi >= min && spi <= max) ^ invert;
+ duprintf(" result %s\n",r? "PASS" : "FAILED");
+ return r;
+}
+
+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 ahhdr *ah = hdr;
+ const struct ipt_ah *ahinfo = matchinfo;
+
+ if (offset == 0 && datalen < sizeof(struct ahhdr)) {
+ /* We've been asked to examine this packet, and we
+ can't. Hence, no choice but to drop. */
+ duprintf("Dropping evil AH tinygram.\n");
+ *hotdrop = 1;
+ return 0;
+ }
+
+ /* Must not be a fragment. */
+ return !offset
+ && spi_match(ahinfo->spis[0], ahinfo->spis[1],
+ ntohl(ah->spi),
+ !!(ahinfo->invflags & IPT_AH_INV_SPI));
+}
+
+/* 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 matchinfosize,
+ unsigned int hook_mask)
+{
+ const struct ipt_ah *ahinfo = matchinfo;
+
+ /* Must specify proto == AH, and no unknown invflags */
+ if (ip->proto != IPPROTO_AH || (ip->invflags & IPT_INV_PROTO)) {
+ duprintf("ipt_ah: Protocol %u != %u\n", ip->proto,
+ IPPROTO_AH);
+ return 0;
+ }
+ if (matchinfosize != IPT_ALIGN(sizeof(struct ipt_ah))) {
+ duprintf("ipt_ah: matchsize %u != %u\n",
+ matchinfosize, IPT_ALIGN(sizeof(struct ipt_ah)));
+ return 0;
+ }
+ if (ahinfo->invflags & ~IPT_AH_INV_MASK) {
+ duprintf("ipt_ah: unknown flags %X\n",
+ ahinfo->invflags);
+ return 0;
+ }
+
+ return 1;
+}
+
+static struct ipt_match ah_match
+= { { NULL, NULL }, "ah", &match, &checkentry, NULL, THIS_MODULE };
+
+static int __init init(void)
+{
+ return ipt_register_match(&ah_match);
+}
+
+static void __exit cleanup(void)
+{
+ ipt_unregister_match(&ah_match);
+}
+
+module_init(init);
+module_exit(cleanup);