diff options
Diffstat (limited to 'net/ipv6/netfilter')
-rw-r--r-- | net/ipv6/netfilter/ip6t_SYNPROXY.c | 420 | ||||
-rw-r--r-- | net/ipv6/netfilter/ip6table_raw.c | 2 | ||||
-rw-r--r-- | net/ipv6/netfilter/nf_conntrack_reasm.c | 53 |
3 files changed, 36 insertions, 439 deletions
diff --git a/net/ipv6/netfilter/ip6t_SYNPROXY.c b/net/ipv6/netfilter/ip6t_SYNPROXY.c index 41325d517478..e77ea1ed5edd 100644 --- a/net/ipv6/netfilter/ip6t_SYNPROXY.c +++ b/net/ipv6/netfilter/ip6t_SYNPROXY.c @@ -3,272 +3,11 @@ * Copyright (c) 2013 Patrick McHardy <kaber@trash.net> */ -#include <linux/module.h> -#include <linux/skbuff.h> -#include <net/ip6_checksum.h> -#include <net/ip6_route.h> -#include <net/tcp.h> - #include <linux/netfilter_ipv6/ip6_tables.h> #include <linux/netfilter/x_tables.h> #include <linux/netfilter/xt_SYNPROXY.h> -#include <net/netfilter/nf_conntrack.h> -#include <net/netfilter/nf_conntrack_seqadj.h> -#include <net/netfilter/nf_conntrack_synproxy.h> -#include <net/netfilter/nf_conntrack_ecache.h> - -static struct ipv6hdr * -synproxy_build_ip(struct net *net, struct sk_buff *skb, - const struct in6_addr *saddr, - const struct in6_addr *daddr) -{ - struct ipv6hdr *iph; - - skb_reset_network_header(skb); - iph = skb_put(skb, sizeof(*iph)); - ip6_flow_hdr(iph, 0, 0); - iph->hop_limit = net->ipv6.devconf_all->hop_limit; - iph->nexthdr = IPPROTO_TCP; - iph->saddr = *saddr; - iph->daddr = *daddr; - - return iph; -} - -static void -synproxy_send_tcp(struct net *net, - const struct sk_buff *skb, struct sk_buff *nskb, - struct nf_conntrack *nfct, enum ip_conntrack_info ctinfo, - struct ipv6hdr *niph, struct tcphdr *nth, - unsigned int tcp_hdr_size) -{ - struct dst_entry *dst; - struct flowi6 fl6; - - nth->check = ~tcp_v6_check(tcp_hdr_size, &niph->saddr, &niph->daddr, 0); - nskb->ip_summed = CHECKSUM_PARTIAL; - nskb->csum_start = (unsigned char *)nth - nskb->head; - nskb->csum_offset = offsetof(struct tcphdr, check); - - memset(&fl6, 0, sizeof(fl6)); - fl6.flowi6_proto = IPPROTO_TCP; - fl6.saddr = niph->saddr; - fl6.daddr = niph->daddr; - fl6.fl6_sport = nth->source; - fl6.fl6_dport = nth->dest; - security_skb_classify_flow((struct sk_buff *)skb, flowi6_to_flowi(&fl6)); - dst = ip6_route_output(net, NULL, &fl6); - if (dst->error) { - dst_release(dst); - goto free_nskb; - } - dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0); - if (IS_ERR(dst)) - goto free_nskb; - - skb_dst_set(nskb, dst); - - if (nfct) { - nf_ct_set(nskb, (struct nf_conn *)nfct, ctinfo); - nf_conntrack_get(nfct); - } - - ip6_local_out(net, nskb->sk, nskb); - return; - -free_nskb: - kfree_skb(nskb); -} - -static void -synproxy_send_client_synack(struct net *net, - const struct sk_buff *skb, const struct tcphdr *th, - const struct synproxy_options *opts) -{ - struct sk_buff *nskb; - struct ipv6hdr *iph, *niph; - struct tcphdr *nth; - unsigned int tcp_hdr_size; - u16 mss = opts->mss; - - iph = ipv6_hdr(skb); - - tcp_hdr_size = sizeof(*nth) + synproxy_options_size(opts); - nskb = alloc_skb(sizeof(*niph) + tcp_hdr_size + MAX_TCP_HEADER, - GFP_ATOMIC); - if (nskb == NULL) - return; - skb_reserve(nskb, MAX_TCP_HEADER); - - niph = synproxy_build_ip(net, nskb, &iph->daddr, &iph->saddr); - - skb_reset_transport_header(nskb); - nth = skb_put(nskb, tcp_hdr_size); - nth->source = th->dest; - nth->dest = th->source; - nth->seq = htonl(__cookie_v6_init_sequence(iph, th, &mss)); - nth->ack_seq = htonl(ntohl(th->seq) + 1); - tcp_flag_word(nth) = TCP_FLAG_SYN | TCP_FLAG_ACK; - if (opts->options & XT_SYNPROXY_OPT_ECN) - tcp_flag_word(nth) |= TCP_FLAG_ECE; - nth->doff = tcp_hdr_size / 4; - nth->window = 0; - nth->check = 0; - nth->urg_ptr = 0; - - synproxy_build_options(nth, opts); - - synproxy_send_tcp(net, skb, nskb, skb_nfct(skb), - IP_CT_ESTABLISHED_REPLY, niph, nth, tcp_hdr_size); -} -static void -synproxy_send_server_syn(struct net *net, - const struct sk_buff *skb, const struct tcphdr *th, - const struct synproxy_options *opts, u32 recv_seq) -{ - struct synproxy_net *snet = synproxy_pernet(net); - struct sk_buff *nskb; - struct ipv6hdr *iph, *niph; - struct tcphdr *nth; - unsigned int tcp_hdr_size; - - iph = ipv6_hdr(skb); - - tcp_hdr_size = sizeof(*nth) + synproxy_options_size(opts); - nskb = alloc_skb(sizeof(*niph) + tcp_hdr_size + MAX_TCP_HEADER, - GFP_ATOMIC); - if (nskb == NULL) - return; - skb_reserve(nskb, MAX_TCP_HEADER); - - niph = synproxy_build_ip(net, nskb, &iph->saddr, &iph->daddr); - - skb_reset_transport_header(nskb); - nth = skb_put(nskb, tcp_hdr_size); - nth->source = th->source; - nth->dest = th->dest; - nth->seq = htonl(recv_seq - 1); - /* ack_seq is used to relay our ISN to the synproxy hook to initialize - * sequence number translation once a connection tracking entry exists. - */ - nth->ack_seq = htonl(ntohl(th->ack_seq) - 1); - tcp_flag_word(nth) = TCP_FLAG_SYN; - if (opts->options & XT_SYNPROXY_OPT_ECN) - tcp_flag_word(nth) |= TCP_FLAG_ECE | TCP_FLAG_CWR; - nth->doff = tcp_hdr_size / 4; - nth->window = th->window; - nth->check = 0; - nth->urg_ptr = 0; - - synproxy_build_options(nth, opts); - - synproxy_send_tcp(net, skb, nskb, &snet->tmpl->ct_general, IP_CT_NEW, - niph, nth, tcp_hdr_size); -} - -static void -synproxy_send_server_ack(struct net *net, - const struct ip_ct_tcp *state, - const struct sk_buff *skb, const struct tcphdr *th, - const struct synproxy_options *opts) -{ - struct sk_buff *nskb; - struct ipv6hdr *iph, *niph; - struct tcphdr *nth; - unsigned int tcp_hdr_size; - - iph = ipv6_hdr(skb); - - tcp_hdr_size = sizeof(*nth) + synproxy_options_size(opts); - nskb = alloc_skb(sizeof(*niph) + tcp_hdr_size + MAX_TCP_HEADER, - GFP_ATOMIC); - if (nskb == NULL) - return; - skb_reserve(nskb, MAX_TCP_HEADER); - - niph = synproxy_build_ip(net, nskb, &iph->daddr, &iph->saddr); - - skb_reset_transport_header(nskb); - nth = skb_put(nskb, tcp_hdr_size); - nth->source = th->dest; - nth->dest = th->source; - nth->seq = htonl(ntohl(th->ack_seq)); - nth->ack_seq = htonl(ntohl(th->seq) + 1); - tcp_flag_word(nth) = TCP_FLAG_ACK; - nth->doff = tcp_hdr_size / 4; - nth->window = htons(state->seen[IP_CT_DIR_ORIGINAL].td_maxwin); - nth->check = 0; - nth->urg_ptr = 0; - - synproxy_build_options(nth, opts); - - synproxy_send_tcp(net, skb, nskb, NULL, 0, niph, nth, tcp_hdr_size); -} - -static void -synproxy_send_client_ack(struct net *net, - const struct sk_buff *skb, const struct tcphdr *th, - const struct synproxy_options *opts) -{ - struct sk_buff *nskb; - struct ipv6hdr *iph, *niph; - struct tcphdr *nth; - unsigned int tcp_hdr_size; - - iph = ipv6_hdr(skb); - - tcp_hdr_size = sizeof(*nth) + synproxy_options_size(opts); - nskb = alloc_skb(sizeof(*niph) + tcp_hdr_size + MAX_TCP_HEADER, - GFP_ATOMIC); - if (nskb == NULL) - return; - skb_reserve(nskb, MAX_TCP_HEADER); - - niph = synproxy_build_ip(net, nskb, &iph->saddr, &iph->daddr); - - skb_reset_transport_header(nskb); - nth = skb_put(nskb, tcp_hdr_size); - nth->source = th->source; - nth->dest = th->dest; - nth->seq = htonl(ntohl(th->seq) + 1); - nth->ack_seq = th->ack_seq; - tcp_flag_word(nth) = TCP_FLAG_ACK; - nth->doff = tcp_hdr_size / 4; - nth->window = htons(ntohs(th->window) >> opts->wscale); - nth->check = 0; - nth->urg_ptr = 0; - - synproxy_build_options(nth, opts); - - synproxy_send_tcp(net, skb, nskb, skb_nfct(skb), - IP_CT_ESTABLISHED_REPLY, niph, nth, tcp_hdr_size); -} - -static bool -synproxy_recv_client_ack(struct net *net, - const struct sk_buff *skb, const struct tcphdr *th, - struct synproxy_options *opts, u32 recv_seq) -{ - struct synproxy_net *snet = synproxy_pernet(net); - int mss; - - mss = __cookie_v6_check(ipv6_hdr(skb), th, ntohl(th->ack_seq) - 1); - if (mss == 0) { - this_cpu_inc(snet->stats->cookie_invalid); - return false; - } - - this_cpu_inc(snet->stats->cookie_valid); - opts->mss = mss; - opts->options |= XT_SYNPROXY_OPT_MSS; - - if (opts->options & XT_SYNPROXY_OPT_TIMESTAMP) - synproxy_check_timestamp_cookie(opts); - - synproxy_send_server_syn(net, skb, th, opts, recv_seq); - return true; -} +#include <net/netfilter/nf_synproxy.h> static unsigned int synproxy_tg6(struct sk_buff *skb, const struct xt_action_param *par) @@ -304,13 +43,14 @@ synproxy_tg6(struct sk_buff *skb, const struct xt_action_param *par) XT_SYNPROXY_OPT_SACK_PERM | XT_SYNPROXY_OPT_ECN); - synproxy_send_client_synack(net, skb, th, &opts); + synproxy_send_client_synack_ipv6(net, skb, th, &opts); consume_skb(skb); return NF_STOLEN; } else if (th->ack && !(th->fin || th->rst || th->syn)) { /* ACK from client */ - if (synproxy_recv_client_ack(net, skb, th, &opts, ntohl(th->seq))) { + if (synproxy_recv_client_ack_ipv6(net, skb, th, &opts, + ntohl(th->seq))) { consume_skb(skb); return NF_STOLEN; } else { @@ -321,141 +61,6 @@ synproxy_tg6(struct sk_buff *skb, const struct xt_action_param *par) return XT_CONTINUE; } -static unsigned int ipv6_synproxy_hook(void *priv, - struct sk_buff *skb, - const struct nf_hook_state *nhs) -{ - struct net *net = nhs->net; - struct synproxy_net *snet = synproxy_pernet(net); - enum ip_conntrack_info ctinfo; - struct nf_conn *ct; - struct nf_conn_synproxy *synproxy; - struct synproxy_options opts = {}; - const struct ip_ct_tcp *state; - struct tcphdr *th, _th; - __be16 frag_off; - u8 nexthdr; - int thoff; - - ct = nf_ct_get(skb, &ctinfo); - if (ct == NULL) - return NF_ACCEPT; - - synproxy = nfct_synproxy(ct); - if (synproxy == NULL) - return NF_ACCEPT; - - if (nf_is_loopback_packet(skb)) - return NF_ACCEPT; - - nexthdr = ipv6_hdr(skb)->nexthdr; - thoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, - &frag_off); - if (thoff < 0 || nexthdr != IPPROTO_TCP) - return NF_ACCEPT; - - th = skb_header_pointer(skb, thoff, sizeof(_th), &_th); - if (th == NULL) - return NF_DROP; - - state = &ct->proto.tcp; - switch (state->state) { - case TCP_CONNTRACK_CLOSE: - if (th->rst && !test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { - nf_ct_seqadj_init(ct, ctinfo, synproxy->isn - - ntohl(th->seq) + 1); - break; - } - - if (!th->syn || th->ack || - CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) - break; - - /* Reopened connection - reset the sequence number and timestamp - * adjustments, they will get initialized once the connection is - * reestablished. - */ - nf_ct_seqadj_init(ct, ctinfo, 0); - synproxy->tsoff = 0; - this_cpu_inc(snet->stats->conn_reopened); - - /* fall through */ - case TCP_CONNTRACK_SYN_SENT: - if (!synproxy_parse_options(skb, thoff, th, &opts)) - return NF_DROP; - - if (!th->syn && th->ack && - CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) { - /* Keep-Alives are sent with SEG.SEQ = SND.NXT-1, - * therefore we need to add 1 to make the SYN sequence - * number match the one of first SYN. - */ - if (synproxy_recv_client_ack(net, skb, th, &opts, - ntohl(th->seq) + 1)) { - this_cpu_inc(snet->stats->cookie_retrans); - consume_skb(skb); - return NF_STOLEN; - } else { - return NF_DROP; - } - } - - synproxy->isn = ntohl(th->ack_seq); - if (opts.options & XT_SYNPROXY_OPT_TIMESTAMP) - synproxy->its = opts.tsecr; - - nf_conntrack_event_cache(IPCT_SYNPROXY, ct); - break; - case TCP_CONNTRACK_SYN_RECV: - if (!th->syn || !th->ack) - break; - - if (!synproxy_parse_options(skb, thoff, th, &opts)) - return NF_DROP; - - if (opts.options & XT_SYNPROXY_OPT_TIMESTAMP) { - synproxy->tsoff = opts.tsval - synproxy->its; - nf_conntrack_event_cache(IPCT_SYNPROXY, ct); - } - - opts.options &= ~(XT_SYNPROXY_OPT_MSS | - XT_SYNPROXY_OPT_WSCALE | - XT_SYNPROXY_OPT_SACK_PERM); - - swap(opts.tsval, opts.tsecr); - synproxy_send_server_ack(net, state, skb, th, &opts); - - nf_ct_seqadj_init(ct, ctinfo, synproxy->isn - ntohl(th->seq)); - nf_conntrack_event_cache(IPCT_SEQADJ, ct); - - swap(opts.tsval, opts.tsecr); - synproxy_send_client_ack(net, skb, th, &opts); - - consume_skb(skb); - return NF_STOLEN; - default: - break; - } - - synproxy_tstamp_adjust(skb, thoff, th, ct, ctinfo, synproxy); - return NF_ACCEPT; -} - -static const struct nf_hook_ops ipv6_synproxy_ops[] = { - { - .hook = ipv6_synproxy_hook, - .pf = NFPROTO_IPV6, - .hooknum = NF_INET_LOCAL_IN, - .priority = NF_IP_PRI_CONNTRACK_CONFIRM - 1, - }, - { - .hook = ipv6_synproxy_hook, - .pf = NFPROTO_IPV6, - .hooknum = NF_INET_POST_ROUTING, - .priority = NF_IP_PRI_CONNTRACK_CONFIRM - 1, - }, -}; - static int synproxy_tg6_check(const struct xt_tgchk_param *par) { struct synproxy_net *snet = synproxy_pernet(par->net); @@ -471,16 +76,12 @@ static int synproxy_tg6_check(const struct xt_tgchk_param *par) if (err) return err; - if (snet->hook_ref6 == 0) { - err = nf_register_net_hooks(par->net, ipv6_synproxy_ops, - ARRAY_SIZE(ipv6_synproxy_ops)); - if (err) { - nf_ct_netns_put(par->net, par->family); - return err; - } + err = nf_synproxy_ipv6_init(snet, par->net); + if (err) { + nf_ct_netns_put(par->net, par->family); + return err; } - snet->hook_ref6++; return err; } @@ -488,10 +89,7 @@ static void synproxy_tg6_destroy(const struct xt_tgdtor_param *par) { struct synproxy_net *snet = synproxy_pernet(par->net); - snet->hook_ref6--; - if (snet->hook_ref6 == 0) - nf_unregister_net_hooks(par->net, ipv6_synproxy_ops, - ARRAY_SIZE(ipv6_synproxy_ops)); + nf_synproxy_ipv6_fini(snet, par->net); nf_ct_netns_put(par->net, par->family); } diff --git a/net/ipv6/netfilter/ip6table_raw.c b/net/ipv6/netfilter/ip6table_raw.c index 3f7d4691c423..a22100b1cf2c 100644 --- a/net/ipv6/netfilter/ip6table_raw.c +++ b/net/ipv6/netfilter/ip6table_raw.c @@ -2,7 +2,7 @@ /* * IPv6 raw table, a port of the IPv4 raw table to IPv6 * - * Copyright (C) 2003 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> + * Copyright (C) 2003 Jozsef Kadlecsik <kadlec@netfilter.org> */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/module.h> diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index 84322ce81d70..398e1df41406 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -54,26 +54,21 @@ static struct inet_frags nf_frags; static struct ctl_table nf_ct_frag6_sysctl_table[] = { { .procname = "nf_conntrack_frag6_timeout", - .data = &init_net.nf_frag.frags.timeout, .maxlen = sizeof(unsigned int), .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, { .procname = "nf_conntrack_frag6_low_thresh", - .data = &init_net.nf_frag.frags.low_thresh, .maxlen = sizeof(unsigned long), .mode = 0644, .proc_handler = proc_doulongvec_minmax, - .extra2 = &init_net.nf_frag.frags.high_thresh }, { .procname = "nf_conntrack_frag6_high_thresh", - .data = &init_net.nf_frag.frags.high_thresh, .maxlen = sizeof(unsigned long), .mode = 0644, .proc_handler = proc_doulongvec_minmax, - .extra1 = &init_net.nf_frag.frags.low_thresh }, { } }; @@ -89,15 +84,15 @@ static int nf_ct_frag6_sysctl_register(struct net *net) GFP_KERNEL); if (table == NULL) goto err_alloc; - - table[0].data = &net->nf_frag.frags.timeout; - table[1].data = &net->nf_frag.frags.low_thresh; - table[1].extra2 = &net->nf_frag.frags.high_thresh; - table[2].data = &net->nf_frag.frags.high_thresh; - table[2].extra1 = &net->nf_frag.frags.low_thresh; - table[2].extra2 = &init_net.nf_frag.frags.high_thresh; } + table[0].data = &net->nf_frag.fqdir->timeout; + table[1].data = &net->nf_frag.fqdir->low_thresh; + table[1].extra2 = &net->nf_frag.fqdir->high_thresh; + table[2].data = &net->nf_frag.fqdir->high_thresh; + table[2].extra1 = &net->nf_frag.fqdir->low_thresh; + table[2].extra2 = &init_net.nf_frag.fqdir->high_thresh; + hdr = register_net_sysctl(net, "net/netfilter", table); if (hdr == NULL) goto err_reg; @@ -144,12 +139,10 @@ static void nf_ct_frag6_expire(struct timer_list *t) { struct inet_frag_queue *frag = from_timer(frag, t, timer); struct frag_queue *fq; - struct net *net; fq = container_of(frag, struct frag_queue, q); - net = container_of(fq->q.net, struct net, nf_frag.frags); - ip6frag_expire_frag_queue(net, fq); + ip6frag_expire_frag_queue(fq->q.fqdir->net, fq); } /* Creation primitives. */ @@ -165,7 +158,7 @@ static struct frag_queue *fq_find(struct net *net, __be32 id, u32 user, }; struct inet_frag_queue *q; - q = inet_frag_find(&net->nf_frag.frags, &key); + q = inet_frag_find(net->nf_frag.fqdir, &key); if (!q) return NULL; @@ -278,7 +271,7 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb, fq->ecn |= ecn; if (payload_len > fq->q.max_size) fq->q.max_size = payload_len; - add_frag_mem_limit(fq->q.net, skb->truesize); + add_frag_mem_limit(fq->q.fqdir, skb->truesize); /* The first fragment. * nhoffset is obtained from the first fragment, of course. @@ -494,29 +487,35 @@ static int nf_ct_net_init(struct net *net) { int res; - net->nf_frag.frags.high_thresh = IPV6_FRAG_HIGH_THRESH; - net->nf_frag.frags.low_thresh = IPV6_FRAG_LOW_THRESH; - net->nf_frag.frags.timeout = IPV6_FRAG_TIMEOUT; - net->nf_frag.frags.f = &nf_frags; - - res = inet_frags_init_net(&net->nf_frag.frags); + res = fqdir_init(&net->nf_frag.fqdir, &nf_frags, net); if (res < 0) return res; + + net->nf_frag.fqdir->high_thresh = IPV6_FRAG_HIGH_THRESH; + net->nf_frag.fqdir->low_thresh = IPV6_FRAG_LOW_THRESH; + net->nf_frag.fqdir->timeout = IPV6_FRAG_TIMEOUT; + res = nf_ct_frag6_sysctl_register(net); if (res < 0) - inet_frags_exit_net(&net->nf_frag.frags); + fqdir_exit(net->nf_frag.fqdir); return res; } +static void nf_ct_net_pre_exit(struct net *net) +{ + fqdir_pre_exit(net->nf_frag.fqdir); +} + static void nf_ct_net_exit(struct net *net) { nf_ct_frags6_sysctl_unregister(net); - inet_frags_exit_net(&net->nf_frag.frags); + fqdir_exit(net->nf_frag.fqdir); } static struct pernet_operations nf_ct_net_ops = { - .init = nf_ct_net_init, - .exit = nf_ct_net_exit, + .init = nf_ct_net_init, + .pre_exit = nf_ct_net_pre_exit, + .exit = nf_ct_net_exit, }; static const struct rhashtable_params nfct_rhash_params = { |