#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;
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 struct xt_match *match,
- const void *matchinfo,
- int offset,
- unsigned int protoff,
- int *hotdrop)
+static bool
+tcp_mt(const struct sk_buff *skb, const struct net_device *in,
+ const struct net_device *out, const struct xt_match *match,
+ const void *matchinfo, int offset, unsigned int protoff, bool *hotdrop)
{
struct tcphdr _tcph, *th;
const struct xt_tcp *tcpinfo = matchinfo;
*/
if (offset == 1) {
duprintf("Dropping evil TCP offset=1 frag.\n");
- *hotdrop = 1;
+ *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);
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;
+ *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;
+ *hotdrop = true;
+ return false;
}
if (!tcp_find_option(tcpinfo->option, skb, protoff,
th->doff*4 - sizeof(_tcph),
tcpinfo->invflags & XT_TCP_INV_OPTION,
hotdrop))
- return 0;
+ 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,
- const struct xt_match *match,
- void *matchinfo,
- unsigned int hook_mask)
+static bool
+tcp_mt_check(const char *tablename, const void *info,
+ const struct xt_match *match, void *matchinfo,
+ unsigned int hook_mask)
{
const struct xt_tcp *tcpinfo = matchinfo;
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 struct xt_match *match,
- const void *matchinfo,
- int offset,
- unsigned int protoff,
- int *hotdrop)
+static bool
+udp_mt(const struct sk_buff *skb, const struct net_device *in,
+ const struct net_device *out, const struct xt_match *match,
+ const void *matchinfo, int offset, unsigned int protoff, bool *hotdrop)
{
struct udphdr _udph, *uh;
const struct xt_udp *udpinfo = matchinfo;
/* Must not be a fragment. */
if (offset)
- return 0;
+ return false;
uh = skb_header_pointer(skb, protoff, 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;
+ *hotdrop = true;
+ return false;
}
return port_match(udpinfo->spts[0], udpinfo->spts[1],
}
/* Called when user tries to insert an entry of this type. */
-static int
-udp_checkentry(const char *tablename,
- const void *info,
- const struct xt_match *match,
- void *matchinfo,
- unsigned int hook_mask)
+static bool
+udp_mt_check(const char *tablename, const void *info,
+ const struct xt_match *match, void *matchinfo,
+ unsigned int hook_mask)
{
- const struct xt_tcp *udpinfo = matchinfo;
+ const struct xt_udp *udpinfo = matchinfo;
/* Must specify no unknown invflags */
return !(udpinfo->invflags & ~XT_UDP_INV_MASK);
}
-static struct xt_match xt_tcpudp_match[] = {
+static struct xt_match tcpudp_mt_reg[] __read_mostly = {
{
.name = "tcp",
.family = AF_INET,
- .checkentry = tcp_checkentry,
- .match = tcp_match,
+ .checkentry = tcp_mt_check,
+ .match = tcp_mt,
.matchsize = sizeof(struct xt_tcp),
.proto = IPPROTO_TCP,
.me = THIS_MODULE,
{
.name = "tcp",
.family = AF_INET6,
- .checkentry = tcp_checkentry,
- .match = tcp_match,
+ .checkentry = tcp_mt_check,
+ .match = tcp_mt,
.matchsize = sizeof(struct xt_tcp),
.proto = IPPROTO_TCP,
.me = THIS_MODULE,
{
.name = "udp",
.family = AF_INET,
- .checkentry = udp_checkentry,
- .match = udp_match,
+ .checkentry = udp_mt_check,
+ .match = udp_mt,
.matchsize = sizeof(struct xt_udp),
.proto = IPPROTO_UDP,
.me = THIS_MODULE,
{
.name = "udp",
.family = AF_INET6,
- .checkentry = udp_checkentry,
- .match = udp_match,
+ .checkentry = udp_mt_check,
+ .match = udp_mt,
.matchsize = sizeof(struct xt_udp),
.proto = IPPROTO_UDP,
.me = THIS_MODULE,
},
+ {
+ .name = "udplite",
+ .family = AF_INET,
+ .checkentry = udp_mt_check,
+ .match = udp_mt,
+ .matchsize = sizeof(struct xt_udp),
+ .proto = IPPROTO_UDPLITE,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "udplite",
+ .family = AF_INET6,
+ .checkentry = udp_mt_check,
+ .match = udp_mt,
+ .matchsize = sizeof(struct xt_udp),
+ .proto = IPPROTO_UDPLITE,
+ .me = THIS_MODULE,
+ },
};
-static int __init xt_tcpudp_init(void)
+static int __init tcpudp_mt_init(void)
{
- return xt_register_matches(xt_tcpudp_match,
- ARRAY_SIZE(xt_tcpudp_match));
+ return xt_register_matches(tcpudp_mt_reg, ARRAY_SIZE(tcpudp_mt_reg));
}
-static void __exit xt_tcpudp_fini(void)
+static void __exit tcpudp_mt_exit(void)
{
- xt_unregister_matches(xt_tcpudp_match, ARRAY_SIZE(xt_tcpudp_match));
+ xt_unregister_matches(tcpudp_mt_reg, ARRAY_SIZE(tcpudp_mt_reg));
}
-module_init(xt_tcpudp_init);
-module_exit(xt_tcpudp_fini);
+module_init(tcpudp_mt_init);
+module_exit(tcpudp_mt_exit);