X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=net%2Fipv4%2Fnetfilter%2Fnf_conntrack_proto_icmp.c;h=e3dd93623df89175ba6433f0f37fa2abbf20cde7;hb=3666ed1c4837fd6906da0224c5373d7a2186a193;hp=d25002fb8176acdb852c519840ad22c4272e7633;hpb=bff9a89bcac5b68ac0a1ea856b1726a35ae1eabb;p=safe%2Fjmp%2Flinux-2.6 diff --git a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c index d25002f..e3dd936 100644 --- a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c +++ b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c @@ -4,15 +4,9 @@ * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. - * - * 16 Dec 2003: Yasuyuki Kozakai @USAGI - * - enable working with Layer 3 protocol independent connection tracking. - * - * Derived from net/ipv4/netfilter/ip_conntrack_proto_icmp.c */ #include -#include #include #include #include @@ -24,30 +18,25 @@ #include #include #include +#include -static unsigned long nf_ct_icmp_timeout __read_mostly = 30*HZ; - -#if 0 -#define DEBUGP printk -#else -#define DEBUGP(format, args...) -#endif +static unsigned int nf_ct_icmp_timeout __read_mostly = 30*HZ; -static int icmp_pkt_to_tuple(const struct sk_buff *skb, - unsigned int dataoff, - struct nf_conntrack_tuple *tuple) +static bool icmp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff, + struct nf_conntrack_tuple *tuple) { - struct icmphdr _hdr, *hp; + const struct icmphdr *hp; + struct icmphdr _hdr; hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr); if (hp == NULL) - return 0; + return false; tuple->dst.u.icmp.type = hp->type; tuple->src.u.icmp.id = hp->un.echo.id; tuple->dst.u.icmp.code = hp->code; - return 1; + return true; } /* Add 1; spaces filled with 0. */ @@ -62,17 +51,17 @@ static const u_int8_t invmap[] = { [ICMP_ADDRESSREPLY] = ICMP_ADDRESS + 1 }; -static int icmp_invert_tuple(struct nf_conntrack_tuple *tuple, - const struct nf_conntrack_tuple *orig) +static bool icmp_invert_tuple(struct nf_conntrack_tuple *tuple, + const struct nf_conntrack_tuple *orig) { - if (orig->dst.u.icmp.type >= sizeof(invmap) - || !invmap[orig->dst.u.icmp.type]) - return 0; + if (orig->dst.u.icmp.type >= sizeof(invmap) || + !invmap[orig->dst.u.icmp.type]) + return false; tuple->src.u.icmp.id = orig->src.u.icmp.id; tuple->dst.u.icmp.type = invmap[orig->dst.u.icmp.type] - 1; tuple->dst.u.icmp.code = orig->dst.u.icmp.code; - return 1; + return true; } /* Print out the per-protocol part of the tuple. */ @@ -85,41 +74,25 @@ static int icmp_print_tuple(struct seq_file *s, ntohs(tuple->src.u.icmp.id)); } -/* Print out the private part of the conntrack. */ -static int icmp_print_conntrack(struct seq_file *s, - const struct nf_conn *conntrack) -{ - return 0; -} - /* Returns verdict for packet, or -1 for invalid. */ static int icmp_packet(struct nf_conn *ct, const struct sk_buff *skb, unsigned int dataoff, enum ip_conntrack_info ctinfo, - int pf, + u_int8_t pf, unsigned int hooknum) { - /* Try to delete connection immediately after all replies: - won't actually vanish as we still have skb, and del_timer - means this will only run once even if count hits zero twice - (theoretically possible with SMP) */ - if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) { - if (atomic_dec_and_test(&ct->proto.icmp.count) - && del_timer(&ct->timeout)) - ct->timeout.function((unsigned long)ct); - } else { - atomic_inc(&ct->proto.icmp.count); - nf_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE, skb); - nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_icmp_timeout); - } + /* Do not immediately delete the connection after the first + successful reply to avoid excessive conntrackd traffic + and also to handle correctly ICMP echo reply duplicates. */ + nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_icmp_timeout); return NF_ACCEPT; } /* Called when a new connection for this protocol found. */ -static int icmp_new(struct nf_conn *conntrack, - const struct sk_buff *skb, unsigned int dataoff) +static bool icmp_new(struct nf_conn *ct, const struct sk_buff *skb, + unsigned int dataoff) { static const u_int8_t valid_new[] = { [ICMP_ECHO] = 1, @@ -128,116 +101,87 @@ static int icmp_new(struct nf_conn *conntrack, [ICMP_ADDRESS] = 1 }; - if (conntrack->tuplehash[0].tuple.dst.u.icmp.type >= sizeof(valid_new) - || !valid_new[conntrack->tuplehash[0].tuple.dst.u.icmp.type]) { + if (ct->tuplehash[0].tuple.dst.u.icmp.type >= sizeof(valid_new) || + !valid_new[ct->tuplehash[0].tuple.dst.u.icmp.type]) { /* Can't create a new ICMP `conn' with this. */ - DEBUGP("icmp: can't create new conn with type %u\n", - conntrack->tuplehash[0].tuple.dst.u.icmp.type); - NF_CT_DUMP_TUPLE(&conntrack->tuplehash[0].tuple); - return 0; + pr_debug("icmp: can't create new conn with type %u\n", + ct->tuplehash[0].tuple.dst.u.icmp.type); + nf_ct_dump_tuple_ip(&ct->tuplehash[0].tuple); + return false; } - atomic_set(&conntrack->proto.icmp.count, 0); - return 1; + return true; } -extern struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv4; /* Returns conntrack if it dealt with ICMP, and filled in skb fields */ static int -icmp_error_message(struct sk_buff *skb, - enum ip_conntrack_info *ctinfo, - unsigned int hooknum) +icmp_error_message(struct net *net, struct sk_buff *skb, + enum ip_conntrack_info *ctinfo, + unsigned int hooknum) { struct nf_conntrack_tuple innertuple, origtuple; - struct { - struct icmphdr icmp; - struct iphdr ip; - } _in, *inside; - struct nf_conntrack_l4proto *innerproto; - struct nf_conntrack_tuple_hash *h; - int dataoff; + const struct nf_conntrack_l4proto *innerproto; + const struct nf_conntrack_tuple_hash *h; NF_CT_ASSERT(skb->nfct == NULL); - /* Not enough header? */ - inside = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_in), &_in); - if (inside == NULL) - return -NF_ACCEPT; - - /* Ignore ICMP's containing fragments (shouldn't happen) */ - if (inside->ip.frag_off & htons(IP_OFFSET)) { - DEBUGP("icmp_error_message: fragment of proto %u\n", - inside->ip.protocol); - return -NF_ACCEPT; - } - - innerproto = __nf_ct_l4proto_find(PF_INET, inside->ip.protocol); - dataoff = skb->nh.iph->ihl*4 + sizeof(inside->icmp); /* Are they talking about one of our connections? */ - if (!nf_ct_get_tuple(skb, dataoff, dataoff + inside->ip.ihl*4, PF_INET, - inside->ip.protocol, &origtuple, - &nf_conntrack_l3proto_ipv4, innerproto)) { - DEBUGP("icmp_error_message: ! get_tuple p=%u", - inside->ip.protocol); + if (!nf_ct_get_tuplepr(skb, + skb_network_offset(skb) + ip_hdrlen(skb) + + sizeof(struct icmphdr), + PF_INET, &origtuple)) { + pr_debug("icmp_error_message: failed to get tuple\n"); return -NF_ACCEPT; } - /* Ordinarily, we'd expect the inverted tupleproto, but it's - been preserved inside the ICMP. */ - if (!nf_ct_invert_tuple(&innertuple, &origtuple, + /* rcu_read_lock()ed by nf_hook_slow */ + innerproto = __nf_ct_l4proto_find(PF_INET, origtuple.dst.protonum); + + /* Ordinarily, we'd expect the inverted tupleproto, but it's + been preserved inside the ICMP. */ + if (!nf_ct_invert_tuple(&innertuple, &origtuple, &nf_conntrack_l3proto_ipv4, innerproto)) { - DEBUGP("icmp_error_message: no match\n"); + pr_debug("icmp_error_message: no match\n"); return -NF_ACCEPT; } *ctinfo = IP_CT_RELATED; - h = nf_conntrack_find_get(&innertuple, NULL); + h = nf_conntrack_find_get(net, &innertuple); if (!h) { - /* Locally generated ICMPs will match inverted if they - haven't been SNAT'ed yet */ - /* FIXME: NAT code has to handle half-done double NAT --RR */ - if (hooknum == NF_IP_LOCAL_OUT) - h = nf_conntrack_find_get(&origtuple, NULL); - - if (!h) { - DEBUGP("icmp_error_message: no match\n"); - return -NF_ACCEPT; - } - - /* Reverse direction from that found */ - if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) - *ctinfo += IP_CT_IS_REPLY; - } else { - if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) - *ctinfo += IP_CT_IS_REPLY; + pr_debug("icmp_error_message: no match\n"); + return -NF_ACCEPT; } - /* Update skb to refer to this connection */ - skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general; - skb->nfctinfo = *ctinfo; - return -NF_ACCEPT; + if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) + *ctinfo += IP_CT_IS_REPLY; + + /* Update skb to refer to this connection */ + skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general; + skb->nfctinfo = *ctinfo; + return -NF_ACCEPT; } /* Small and modified version of icmp_rcv */ static int -icmp_error(struct sk_buff *skb, unsigned int dataoff, - enum ip_conntrack_info *ctinfo, int pf, unsigned int hooknum) +icmp_error(struct net *net, struct sk_buff *skb, unsigned int dataoff, + enum ip_conntrack_info *ctinfo, u_int8_t pf, unsigned int hooknum) { - struct icmphdr _ih, *icmph; + const struct icmphdr *icmph; + struct icmphdr _ih; /* Not enough header? */ - icmph = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_ih), &_ih); + icmph = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_ih), &_ih); if (icmph == NULL) { - if (LOG_INVALID(IPPROTO_ICMP)) + if (LOG_INVALID(net, IPPROTO_ICMP)) nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL, "nf_ct_icmp: short packet "); return -NF_ACCEPT; } /* See ip_conntrack_proto_tcp.c */ - if (nf_conntrack_checksum && hooknum == NF_IP_PRE_ROUTING && + if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING && nf_ip_checksum(skb, hooknum, dataoff, 0)) { - if (LOG_INVALID(IPPROTO_ICMP)) + if (LOG_INVALID(net, IPPROTO_ICMP)) nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL, "nf_ct_icmp: bad HW ICMP checksum "); return -NF_ACCEPT; @@ -250,110 +194,103 @@ icmp_error(struct sk_buff *skb, unsigned int dataoff, * discarded. */ if (icmph->type > NR_ICMP_TYPES) { - if (LOG_INVALID(IPPROTO_ICMP)) + if (LOG_INVALID(net, IPPROTO_ICMP)) nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL, "nf_ct_icmp: invalid ICMP type "); return -NF_ACCEPT; } /* Need to track icmp error message? */ - if (icmph->type != ICMP_DEST_UNREACH - && icmph->type != ICMP_SOURCE_QUENCH - && icmph->type != ICMP_TIME_EXCEEDED - && icmph->type != ICMP_PARAMETERPROB - && icmph->type != ICMP_REDIRECT) + if (icmph->type != ICMP_DEST_UNREACH && + icmph->type != ICMP_SOURCE_QUENCH && + icmph->type != ICMP_TIME_EXCEEDED && + icmph->type != ICMP_PARAMETERPROB && + icmph->type != ICMP_REDIRECT) return NF_ACCEPT; - return icmp_error_message(skb, ctinfo, hooknum); + return icmp_error_message(net, skb, ctinfo, hooknum); } -#if defined(CONFIG_NF_CT_NETLINK) || \ - defined(CONFIG_NF_CT_NETLINK_MODULE) +#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) #include #include -static int icmp_tuple_to_nfattr(struct sk_buff *skb, +static int icmp_tuple_to_nlattr(struct sk_buff *skb, const struct nf_conntrack_tuple *t) { - NFA_PUT(skb, CTA_PROTO_ICMP_ID, sizeof(u_int16_t), - &t->src.u.icmp.id); - NFA_PUT(skb, CTA_PROTO_ICMP_TYPE, sizeof(u_int8_t), - &t->dst.u.icmp.type); - NFA_PUT(skb, CTA_PROTO_ICMP_CODE, sizeof(u_int8_t), - &t->dst.u.icmp.code); + NLA_PUT_BE16(skb, CTA_PROTO_ICMP_ID, t->src.u.icmp.id); + NLA_PUT_U8(skb, CTA_PROTO_ICMP_TYPE, t->dst.u.icmp.type); + NLA_PUT_U8(skb, CTA_PROTO_ICMP_CODE, t->dst.u.icmp.code); return 0; -nfattr_failure: +nla_put_failure: return -1; } -static const size_t cta_min_proto[CTA_PROTO_MAX] = { - [CTA_PROTO_ICMP_TYPE-1] = sizeof(u_int8_t), - [CTA_PROTO_ICMP_CODE-1] = sizeof(u_int8_t), - [CTA_PROTO_ICMP_ID-1] = sizeof(u_int16_t) +static const struct nla_policy icmp_nla_policy[CTA_PROTO_MAX+1] = { + [CTA_PROTO_ICMP_TYPE] = { .type = NLA_U8 }, + [CTA_PROTO_ICMP_CODE] = { .type = NLA_U8 }, + [CTA_PROTO_ICMP_ID] = { .type = NLA_U16 }, }; -static int icmp_nfattr_to_tuple(struct nfattr *tb[], +static int icmp_nlattr_to_tuple(struct nlattr *tb[], struct nf_conntrack_tuple *tuple) { - if (!tb[CTA_PROTO_ICMP_TYPE-1] - || !tb[CTA_PROTO_ICMP_CODE-1] - || !tb[CTA_PROTO_ICMP_ID-1]) - return -EINVAL; - - if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto)) + if (!tb[CTA_PROTO_ICMP_TYPE] || + !tb[CTA_PROTO_ICMP_CODE] || + !tb[CTA_PROTO_ICMP_ID]) return -EINVAL; - tuple->dst.u.icmp.type = - *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_ICMP_TYPE-1]); - tuple->dst.u.icmp.code = - *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_ICMP_CODE-1]); - tuple->src.u.icmp.id = - *(__be16 *)NFA_DATA(tb[CTA_PROTO_ICMP_ID-1]); + tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMP_TYPE]); + tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMP_CODE]); + tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMP_ID]); - if (tuple->dst.u.icmp.type >= sizeof(invmap) - || !invmap[tuple->dst.u.icmp.type]) + if (tuple->dst.u.icmp.type >= sizeof(invmap) || + !invmap[tuple->dst.u.icmp.type]) return -EINVAL; return 0; } + +static int icmp_nlattr_tuple_size(void) +{ + return nla_policy_len(icmp_nla_policy, CTA_PROTO_MAX + 1); +} #endif #ifdef CONFIG_SYSCTL static struct ctl_table_header *icmp_sysctl_header; static struct ctl_table icmp_sysctl_table[] = { { - .ctl_name = NET_NF_CONNTRACK_ICMP_TIMEOUT, .procname = "nf_conntrack_icmp_timeout", .data = &nf_ct_icmp_timeout, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = &proc_dointvec_jiffies, + .proc_handler = proc_dointvec_jiffies, }, - { + { .ctl_name = 0 } }; #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT static struct ctl_table icmp_compat_sysctl_table[] = { { - .ctl_name = NET_IPV4_NF_CONNTRACK_ICMP_TIMEOUT, .procname = "ip_conntrack_icmp_timeout", .data = &nf_ct_icmp_timeout, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = &proc_dointvec_jiffies, + .proc_handler = proc_dointvec_jiffies, }, - { + { .ctl_name = 0 } }; #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */ #endif /* CONFIG_SYSCTL */ -struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp = +struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp __read_mostly = { .l3proto = PF_INET, .l4proto = IPPROTO_ICMP, @@ -361,16 +298,16 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp = .pkt_to_tuple = icmp_pkt_to_tuple, .invert_tuple = icmp_invert_tuple, .print_tuple = icmp_print_tuple, - .print_conntrack = icmp_print_conntrack, .packet = icmp_packet, .new = icmp_new, .error = icmp_error, .destroy = NULL, .me = NULL, -#if defined(CONFIG_NF_CT_NETLINK) || \ - defined(CONFIG_NF_CT_NETLINK_MODULE) - .tuple_to_nfattr = icmp_tuple_to_nfattr, - .nfattr_to_tuple = icmp_nfattr_to_tuple, +#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) + .tuple_to_nlattr = icmp_tuple_to_nlattr, + .nlattr_tuple_size = icmp_nlattr_tuple_size, + .nlattr_to_tuple = icmp_nlattr_to_tuple, + .nla_policy = icmp_nla_policy, #endif #ifdef CONFIG_SYSCTL .ctl_table_header = &icmp_sysctl_header, @@ -380,5 +317,3 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp = #endif #endif }; - -EXPORT_SYMBOL(nf_conntrack_l4proto_icmp);