diff options
Diffstat (limited to 'net/netfilter/xt_socket.c')
| -rw-r--r-- | net/netfilter/xt_socket.c | 66 |
1 files changed, 61 insertions, 5 deletions
diff --git a/net/netfilter/xt_socket.c b/net/netfilter/xt_socket.c index f8b71911037a..a7dd108d4063 100644 --- a/net/netfilter/xt_socket.c +++ b/net/netfilter/xt_socket.c @@ -19,12 +19,12 @@ #include <net/icmp.h> #include <net/sock.h> #include <net/inet_sock.h> -#include <net/netfilter/nf_tproxy_core.h> #include <net/netfilter/ipv4/nf_defrag_ipv4.h> #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) #define XT_SOCKET_HAVE_IPV6 1 #include <linux/netfilter_ipv6/ip6_tables.h> +#include <net/inet6_hashtables.h> #include <net/netfilter/ipv6/nf_defrag_ipv6.h> #endif @@ -101,6 +101,43 @@ extract_icmp4_fields(const struct sk_buff *skb, return 0; } +/* "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 struct sock * +xt_socket_get_sock_v4(struct net *net, const u8 protocol, + const __be32 saddr, const __be32 daddr, + const __be16 sport, const __be16 dport, + const struct net_device *in) +{ + switch (protocol) { + case IPPROTO_TCP: + return __inet_lookup(net, &tcp_hashinfo, + saddr, sport, daddr, dport, + in->ifindex); + case IPPROTO_UDP: + return udp4_lib_lookup(net, saddr, sport, daddr, dport, + in->ifindex); + } + return NULL; +} + static bool socket_match(const struct sk_buff *skb, struct xt_action_param *par, const struct xt_socket_mtinfo1 *info) @@ -156,9 +193,9 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par, #endif if (!sk) - sk = nf_tproxy_get_sock_v4(dev_net(skb->dev), protocol, + sk = xt_socket_get_sock_v4(dev_net(skb->dev), protocol, saddr, daddr, sport, dport, - par->in, NFT_LOOKUP_ANY); + par->in); if (sk) { bool wildcard; bool transparent = true; @@ -261,6 +298,25 @@ extract_icmp6_fields(const struct sk_buff *skb, return 0; } +static struct sock * +xt_socket_get_sock_v6(struct net *net, const u8 protocol, + const struct in6_addr *saddr, const struct in6_addr *daddr, + const __be16 sport, const __be16 dport, + const struct net_device *in) +{ + switch (protocol) { + case IPPROTO_TCP: + return inet6_lookup(net, &tcp_hashinfo, + saddr, sport, daddr, dport, + in->ifindex); + case IPPROTO_UDP: + return udp6_lib_lookup(net, saddr, sport, daddr, dport, + in->ifindex); + } + + return NULL; +} + static bool socket_mt6_v1_v2(const struct sk_buff *skb, struct xt_action_param *par) { @@ -298,9 +354,9 @@ socket_mt6_v1_v2(const struct sk_buff *skb, struct xt_action_param *par) } if (!sk) - sk = nf_tproxy_get_sock_v6(dev_net(skb->dev), tproto, + sk = xt_socket_get_sock_v6(dev_net(skb->dev), tproto, saddr, daddr, sport, dport, - par->in, NFT_LOOKUP_ANY); + par->in); if (sk) { bool wildcard; bool transparent = true; |