diff options
Diffstat (limited to 'extensions/libnetfilter_conntrack_tcp.c')
-rw-r--r-- | extensions/libnetfilter_conntrack_tcp.c | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/extensions/libnetfilter_conntrack_tcp.c b/extensions/libnetfilter_conntrack_tcp.c new file mode 100644 index 0000000..5b53fd1 --- /dev/null +++ b/extensions/libnetfilter_conntrack_tcp.c @@ -0,0 +1,84 @@ +/* + * (C) 2005 by Pablo Neira Ayuso <pablo@netfilter.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ +#include <stdio.h> +#include <getopt.h> +#include <stdlib.h> +#include <string.h> +#include <netinet/in.h> /* For htons */ +#include <linux/netfilter/nfnetlink_conntrack.h> +#include <libnetfilter_conntrack/libnetfilter_conntrack.h> + +static const char *states[] = { + "NONE", + "SYN_SENT", + "SYN_RECV", + "ESTABLISHED", + "FIN_WAIT", + "CLOSE_WAIT", + "LAST_ACK", + "TIME_WAIT", + "CLOSE", + "LISTEN" +}; + +void parse_proto(struct nfattr *cda[], struct nfct_tuple *tuple) +{ + if (cda[CTA_PROTO_SRC_PORT-1]) + tuple->l4src.tcp.port = + *(u_int16_t *)NFA_DATA(cda[CTA_PROTO_SRC_PORT-1]); + if (cda[CTA_PROTO_DST_PORT-1]) + tuple->l4dst.tcp.port = + *(u_int16_t *)NFA_DATA(cda[CTA_PROTO_DST_PORT-1]); +} + +void parse_protoinfo(struct nfattr *cda[], struct nfct_conntrack *ct) +{ + struct nfattr *tb[CTA_PROTOINFO_TCP_MAX]; + + nfnl_parse_nested(tb,CTA_PROTOINFO_TCP_MAX, cda[CTA_PROTOINFO_TCP-1]); + + if (tb[CTA_PROTOINFO_TCP_STATE-1]) + ct->protoinfo.tcp.state = + *(u_int8_t *)NFA_DATA(tb[CTA_PROTOINFO_TCP_STATE-1]); +} + +int print_protoinfo(char *buf, union nfct_protoinfo *protoinfo) +{ + return(sprintf(buf, "%s ", states[protoinfo->tcp.state])); +} + +int print_proto(char *buf, struct nfct_tuple *tuple) +{ + return(sprintf(buf, "sport=%u dport=%u ", htons(tuple->l4src.tcp.port), + htons(tuple->l4dst.tcp.port))); +} + +static struct nfct_proto tcp = { + .name = "tcp", + .protonum = IPPROTO_TCP, + .parse_protoinfo = parse_protoinfo, + .parse_proto = parse_proto, + .print_protoinfo = print_protoinfo, + .print_proto = print_proto, + .version = LIBNETFILTER_CONNTRACK_VERSION +}; + +void __attribute__ ((constructor)) init(void); +void __attribute__ ((destructor)) fini(void); + +void init(void) +{ + nfct_register_proto(&tcp); +} + +void fini(void) +{ + nfct_unregister_proto(&tcp); +} |