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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)#include <linux/netfilter_ipv6/ip6_tables.h>#include <net/inet6_hashtables.h>#include <net/netfilter/ipv6/nf_defrag_ipv6.h>#endif
#include <net/netfilter/nf_socket.h>#include <linux/netfilter/xt_socket.h>
/* "socket" match based redirection (no specific rule) * =================================================== * * There are connections with dynamic endpoints (e.g. FTP data * connection) that the user is unable to add explicit rules * for. These are taken care of by a generic "socket" rule. It is * assumed that the proxy application is trusted to open such * connections without explicit iptables rule (except of course the * generic 'socket' rule). In this case the following sockets are * matched in preference order: * * - match: if there's a fully established connection matching the * _packet_ tuple * * - match: if there's a non-zero bound listener (possibly with a * non-local address) We don't accept zero-bound listeners, since * then local services could intercept traffic going through the * box. */static boolsocket_match(const struct sk_buff *skb, struct xt_action_param *par, const struct xt_socket_mtinfo1 *info){ struct sk_buff *pskb = (struct sk_buff *)skb; struct sock *sk = skb->sk;
if (sk && !net_eq(xt_net(par), sock_net(sk))) sk = NULL;
if (!sk) sk = nf_sk_lookup_slow_v4(xt_net(par), skb, xt_in(par));
if (sk) { bool wildcard; bool transparent = true;
/* Ignore sockets listening on INADDR_ANY, * unless XT_SOCKET_NOWILDCARD is set */ wildcard = (!(info->flags & XT_SOCKET_NOWILDCARD) && sk_fullsock(sk) && inet_sk(sk)->inet_rcv_saddr == 0);
/* Ignore non-transparent sockets, * if XT_SOCKET_TRANSPARENT is used */ if (info->flags & XT_SOCKET_TRANSPARENT) transparent = inet_sk_transparent(sk);
if (info->flags & XT_SOCKET_RESTORESKMARK && !wildcard && transparent && sk_fullsock(sk)) pskb->mark = READ_ONCE(sk->sk_mark);
if (sk != skb->sk) sock_gen_put(sk);
if (wildcard || !transparent) sk = NULL; }
return sk != NULL;}
static boolsocket_mt4_v0(const struct sk_buff *skb, struct xt_action_param *par){ static struct xt_socket_mtinfo1 xt_info_v0 = { .flags = 0, };
return socket_match(skb, par, &xt_info_v0);}
static boolsocket_mt4_v1_v2_v3(const struct sk_buff *skb, struct xt_action_param *par){ return socket_match(skb, par, par->matchinfo);}
#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)static boolsocket_mt6_v1_v2_v3(const struct sk_buff *skb, struct xt_action_param *par){ const struct xt_socket_mtinfo1 *info = (struct xt_socket_mtinfo1 *) par->matchinfo; struct sk_buff *pskb = (struct sk_buff *)skb; struct sock *sk = skb->sk;
if (sk && !net_eq(xt_net(par), sock_net(sk))) sk = NULL;
if (!sk) sk = nf_sk_lookup_slow_v6(xt_net(par), skb, xt_in(par));
if (sk) { bool wildcard; bool transparent = true;
/* Ignore sockets listening on INADDR_ANY * unless XT_SOCKET_NOWILDCARD is set */ wildcard = (!(info->flags & XT_SOCKET_NOWILDCARD) && sk_fullsock(sk) && ipv6_addr_any(&sk->sk_v6_rcv_saddr));
/* Ignore non-transparent sockets, * if XT_SOCKET_TRANSPARENT is used */ if (info->flags & XT_SOCKET_TRANSPARENT) transparent = inet_sk_transparent(sk);
if (info->flags & XT_SOCKET_RESTORESKMARK && !wildcard && transparent && sk_fullsock(sk)) pskb->mark = READ_ONCE(sk->sk_mark);
if (sk != skb->sk) sock_gen_put(sk);
if (wildcard || !transparent) sk = NULL; }
return sk != NULL;}#endif
static int socket_mt_enable_defrag(struct net *net, int family){ switch (family) { case NFPROTO_IPV4: return nf_defrag_ipv4_enable(net);#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) case NFPROTO_IPV6: return nf_defrag_ipv6_enable(net);#endif } WARN_ONCE(1, "Unknown family %d\n", family); return 0;}
static int socket_mt_v1_check(const struct xt_mtchk_param *par){ const struct xt_socket_mtinfo1 *info = (struct xt_socket_mtinfo1 *) par->matchinfo;
if (info->flags & ~XT_SOCKET_FLAGS_V1) { pr_info_ratelimited("unknown flags 0x%x\n", info->flags & ~XT_SOCKET_FLAGS_V1); return -EINVAL; }
return socket_mt_enable_defrag(par->net, par->family);}
static int socket_mt_v2_check(const struct xt_mtchk_param *par){ const struct xt_socket_mtinfo2 *info = (struct xt_socket_mtinfo2 *) par->matchinfo;
if (info->flags & ~XT_SOCKET_FLAGS_V2) { pr_info_ratelimited("unknown flags 0x%x\n", info->flags & ~XT_SOCKET_FLAGS_V2); return -EINVAL; }
return socket_mt_enable_defrag(par->net, par->family);}
static int socket_mt_v3_check(const struct xt_mtchk_param *par){ const struct xt_socket_mtinfo3 *info = (struct xt_socket_mtinfo3 *)par->matchinfo;
if (info->flags & ~XT_SOCKET_FLAGS_V3) { pr_info_ratelimited("unknown flags 0x%x\n", info->flags & ~XT_SOCKET_FLAGS_V3); return -EINVAL; }
return socket_mt_enable_defrag(par->net, par->family);}
static void socket_mt_destroy(const struct xt_mtdtor_param *par){ if (par->family == NFPROTO_IPV4) nf_defrag_ipv4_disable(par->net);#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) else if (par->family == NFPROTO_IPV6) nf_defrag_ipv6_disable(par->net);#endif}
static struct xt_match socket_mt_reg[] __read_mostly = { { .name = "socket", .revision = 0, .family = NFPROTO_IPV4, .match = socket_mt4_v0, .hooks = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, }, { .name = "socket", .revision = 1, .family = NFPROTO_IPV4, .match = socket_mt4_v1_v2_v3, .destroy = socket_mt_destroy, .checkentry = socket_mt_v1_check, .matchsize = sizeof(struct xt_socket_mtinfo1), .hooks = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, },#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) { .name = "socket", .revision = 1, .family = NFPROTO_IPV6, .match = socket_mt6_v1_v2_v3, .checkentry = socket_mt_v1_check, .matchsize = sizeof(struct xt_socket_mtinfo1), .destroy = socket_mt_destroy, .hooks = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, },#endif { .name = "socket", .revision = 2, .family = NFPROTO_IPV4, .match = socket_mt4_v1_v2_v3, .checkentry = socket_mt_v2_check, .destroy = socket_mt_destroy, .matchsize = sizeof(struct xt_socket_mtinfo1), .hooks = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, },#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) { .name = "socket", .revision = 2, .family = NFPROTO_IPV6, .match = socket_mt6_v1_v2_v3, .checkentry = socket_mt_v2_check, .destroy = socket_mt_destroy, .matchsize = sizeof(struct xt_socket_mtinfo1), .hooks = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, },#endif { .name = "socket", .revision = 3, .family = NFPROTO_IPV4, .match = socket_mt4_v1_v2_v3, .checkentry = socket_mt_v3_check, .destroy = socket_mt_destroy, .matchsize = sizeof(struct xt_socket_mtinfo1), .hooks = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, },#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) { .name = "socket", .revision = 3, .family = NFPROTO_IPV6, .match = socket_mt6_v1_v2_v3, .checkentry = socket_mt_v3_check, .destroy = socket_mt_destroy, .matchsize = sizeof(struct xt_socket_mtinfo1), .hooks = (1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, },#endif};
static int __init socket_mt_init(void){ return xt_register_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));}
static void __exit socket_mt_exit(void){ xt_unregister_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));}
module_init(socket_mt_init);module_exit(socket_mt_exit);
MODULE_LICENSE("GPL");MODULE_AUTHOR("Krisztian Kovacs, Balazs Scheidler");MODULE_DESCRIPTION("x_tables socket match module");MODULE_ALIAS("ipt_socket");MODULE_ALIAS("ip6t_socket");