#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
-MODULE_DESCRIPTION("x_tables match for TCP and UDP, supports IPv4 and IPv6");
+MODULE_DESCRIPTION("Xtables: TCP, UDP and UDP-Lite match");
MODULE_LICENSE("GPL");
MODULE_ALIAS("xt_tcp");
MODULE_ALIAS("xt_udp");
/* Returns 1 if the port is matched by the range, 0 otherwise */
-static inline int
-port_match(u_int16_t min, u_int16_t max, u_int16_t port, int invert)
+static inline bool
+port_match(u_int16_t min, u_int16_t max, u_int16_t port, bool invert)
{
- int ret;
-
- ret = (port >= min && port <= max) ^ invert;
- return ret;
+ return (port >= min && port <= max) ^ invert;
}
-static int
+static bool
tcp_find_option(u_int8_t option,
const struct sk_buff *skb,
unsigned int protoff,
unsigned int optlen,
- int invert,
- int *hotdrop)
+ bool invert,
+ bool *hotdrop)
{
/* tcp.doff is only 4 bits, ie. max 15 * 4 bytes */
- u_int8_t _opt[60 - sizeof(struct tcphdr)], *op;
+ const u_int8_t *op;
+ u_int8_t _opt[60 - sizeof(struct tcphdr)];
unsigned int i;
duprintf("tcp_match: finding option\n");
op = skb_header_pointer(skb, protoff + sizeof(struct tcphdr),
optlen, _opt);
if (op == NULL) {
- *hotdrop = 1;
- return 0;
+ *hotdrop = true;
+ return false;
}
for (i = 0; i < optlen; ) {
return invert;
}
-static int
-tcp_match(const struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- const void *matchinfo,
- int offset,
- unsigned int protoff,
- int *hotdrop)
+static bool tcp_mt(const struct sk_buff *skb, const struct xt_match_param *par)
{
- struct tcphdr _tcph, *th;
- const struct xt_tcp *tcpinfo = matchinfo;
+ const struct tcphdr *th;
+ struct tcphdr _tcph;
+ const struct xt_tcp *tcpinfo = par->matchinfo;
- if (offset) {
+ if (par->fragoff != 0) {
/* To quote Alan:
Don't allow a fragment of TCP 8 bytes in. Nobody normal
causes this. Its a cracker trying to break in by doing a
flag overwrite to pass the direction checks.
*/
- if (offset == 1) {
+ if (par->fragoff == 1) {
duprintf("Dropping evil TCP offset=1 frag.\n");
- *hotdrop = 1;
+ *par->hotdrop = true;
}
/* Must not be a fragment. */
- return 0;
+ return false;
}
-#define FWINVTCP(bool,invflg) ((bool) ^ !!(tcpinfo->invflags & invflg))
+#define FWINVTCP(bool, invflg) ((bool) ^ !!(tcpinfo->invflags & (invflg)))
- th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
+ th = skb_header_pointer(skb, par->thoff, sizeof(_tcph), &_tcph);
if (th == NULL) {
/* We've been asked to examine this packet, and we
can't. Hence, no choice but to drop. */
duprintf("Dropping evil TCP offset=0 tinygram.\n");
- *hotdrop = 1;
- return 0;
+ *par->hotdrop = true;
+ return false;
}
if (!port_match(tcpinfo->spts[0], tcpinfo->spts[1],
ntohs(th->source),
!!(tcpinfo->invflags & XT_TCP_INV_SRCPT)))
- return 0;
+ return false;
if (!port_match(tcpinfo->dpts[0], tcpinfo->dpts[1],
ntohs(th->dest),
!!(tcpinfo->invflags & XT_TCP_INV_DSTPT)))
- return 0;
+ return false;
if (!FWINVTCP((((unsigned char *)th)[13] & tcpinfo->flg_mask)
== tcpinfo->flg_cmp,
XT_TCP_INV_FLAGS))
- return 0;
+ return false;
if (tcpinfo->option) {
if (th->doff * 4 < sizeof(_tcph)) {
- *hotdrop = 1;
- return 0;
+ *par->hotdrop = true;
+ return false;
}
- if (!tcp_find_option(tcpinfo->option, skb, protoff,
+ if (!tcp_find_option(tcpinfo->option, skb, par->thoff,
th->doff*4 - sizeof(_tcph),
tcpinfo->invflags & XT_TCP_INV_OPTION,
- hotdrop))
- return 0;
+ par->hotdrop))
+ return false;
}
- return 1;
+ return true;
}
-/* Called when user tries to insert an entry of this type. */
-static int
-tcp_checkentry(const char *tablename,
- const void *info,
- void *matchinfo,
- unsigned int matchsize,
- unsigned int hook_mask)
+static bool tcp_mt_check(const struct xt_mtchk_param *par)
{
- const struct xt_tcp *tcpinfo = matchinfo;
+ const struct xt_tcp *tcpinfo = par->matchinfo;
/* Must specify no unknown invflags */
return !(tcpinfo->invflags & ~XT_TCP_INV_MASK);
}
-static int
-udp_match(const struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- const void *matchinfo,
- int offset,
- unsigned int protoff,
- int *hotdrop)
+static bool udp_mt(const struct sk_buff *skb, const struct xt_match_param *par)
{
- struct udphdr _udph, *uh;
- const struct xt_udp *udpinfo = matchinfo;
+ const struct udphdr *uh;
+ struct udphdr _udph;
+ const struct xt_udp *udpinfo = par->matchinfo;
/* Must not be a fragment. */
- if (offset)
- return 0;
+ if (par->fragoff != 0)
+ return false;
- uh = skb_header_pointer(skb, protoff, sizeof(_udph), &_udph);
+ uh = skb_header_pointer(skb, par->thoff, sizeof(_udph), &_udph);
if (uh == NULL) {
/* We've been asked to examine this packet, and we
can't. Hence, no choice but to drop. */
duprintf("Dropping evil UDP tinygram.\n");
- *hotdrop = 1;
- return 0;
+ *par->hotdrop = true;
+ return false;
}
return port_match(udpinfo->spts[0], udpinfo->spts[1],
!!(udpinfo->invflags & XT_UDP_INV_DSTPT));
}
-/* Called when user tries to insert an entry of this type. */
-static int
-udp_checkentry(const char *tablename,
- const void *info,
- void *matchinfo,
- unsigned int matchsize,
- unsigned int hook_mask)
+static bool udp_mt_check(const struct xt_mtchk_param *par)
{
- const struct xt_tcp *udpinfo = matchinfo;
+ const struct xt_udp *udpinfo = par->matchinfo;
/* Must specify no unknown invflags */
return !(udpinfo->invflags & ~XT_UDP_INV_MASK);
}
-static struct xt_match tcp_matchstruct = {
- .name = "tcp",
- .match = tcp_match,
- .matchsize = sizeof(struct xt_tcp),
- .proto = IPPROTO_TCP,
- .checkentry = tcp_checkentry,
- .me = THIS_MODULE,
-};
-
-static struct xt_match tcp6_matchstruct = {
- .name = "tcp",
- .match = tcp_match,
- .matchsize = sizeof(struct xt_tcp),
- .proto = IPPROTO_TCP,
- .checkentry = tcp_checkentry,
- .me = THIS_MODULE,
-};
-
-static struct xt_match udp_matchstruct = {
- .name = "udp",
- .match = udp_match,
- .matchsize = sizeof(struct xt_udp),
- .proto = IPPROTO_UDP,
- .checkentry = udp_checkentry,
- .me = THIS_MODULE,
-};
-static struct xt_match udp6_matchstruct = {
- .name = "udp",
- .match = udp_match,
- .matchsize = sizeof(struct xt_udp),
- .proto = IPPROTO_UDP,
- .checkentry = udp_checkentry,
- .me = THIS_MODULE,
+static struct xt_match tcpudp_mt_reg[] __read_mostly = {
+ {
+ .name = "tcp",
+ .family = NFPROTO_IPV4,
+ .checkentry = tcp_mt_check,
+ .match = tcp_mt,
+ .matchsize = sizeof(struct xt_tcp),
+ .proto = IPPROTO_TCP,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "tcp",
+ .family = NFPROTO_IPV6,
+ .checkentry = tcp_mt_check,
+ .match = tcp_mt,
+ .matchsize = sizeof(struct xt_tcp),
+ .proto = IPPROTO_TCP,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "udp",
+ .family = NFPROTO_IPV4,
+ .checkentry = udp_mt_check,
+ .match = udp_mt,
+ .matchsize = sizeof(struct xt_udp),
+ .proto = IPPROTO_UDP,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "udp",
+ .family = NFPROTO_IPV6,
+ .checkentry = udp_mt_check,
+ .match = udp_mt,
+ .matchsize = sizeof(struct xt_udp),
+ .proto = IPPROTO_UDP,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "udplite",
+ .family = NFPROTO_IPV4,
+ .checkentry = udp_mt_check,
+ .match = udp_mt,
+ .matchsize = sizeof(struct xt_udp),
+ .proto = IPPROTO_UDPLITE,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "udplite",
+ .family = NFPROTO_IPV6,
+ .checkentry = udp_mt_check,
+ .match = udp_mt,
+ .matchsize = sizeof(struct xt_udp),
+ .proto = IPPROTO_UDPLITE,
+ .me = THIS_MODULE,
+ },
};
-static int __init init(void)
+static int __init tcpudp_mt_init(void)
{
- int ret;
- ret = xt_register_match(AF_INET, &tcp_matchstruct);
- if (ret)
- return ret;
-
- ret = xt_register_match(AF_INET6, &tcp6_matchstruct);
- if (ret)
- goto out_unreg_tcp;
-
- ret = xt_register_match(AF_INET, &udp_matchstruct);
- if (ret)
- goto out_unreg_tcp6;
-
- ret = xt_register_match(AF_INET6, &udp6_matchstruct);
- if (ret)
- goto out_unreg_udp;
-
- return ret;
-
-out_unreg_udp:
- xt_unregister_match(AF_INET, &tcp_matchstruct);
-out_unreg_tcp6:
- xt_unregister_match(AF_INET6, &tcp6_matchstruct);
-out_unreg_tcp:
- xt_unregister_match(AF_INET, &tcp_matchstruct);
- return ret;
+ return xt_register_matches(tcpudp_mt_reg, ARRAY_SIZE(tcpudp_mt_reg));
}
-static void __exit fini(void)
+static void __exit tcpudp_mt_exit(void)
{
- xt_unregister_match(AF_INET6, &udp6_matchstruct);
- xt_unregister_match(AF_INET, &udp_matchstruct);
- xt_unregister_match(AF_INET6, &tcp6_matchstruct);
- xt_unregister_match(AF_INET, &tcp_matchstruct);
+ xt_unregister_matches(tcpudp_mt_reg, ARRAY_SIZE(tcpudp_mt_reg));
}
-module_init(init);
-module_exit(fini);
+module_init(tcpudp_mt_init);
+module_exit(tcpudp_mt_exit);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff