From c4f3db15958277c03d1c324894255ea3ecbf86e1 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 11 Oct 2017 10:47:40 +0200 Subject: netfilter: conntrack: add and use nf_l4proto_log_invalid We currently pass down the l4 protocol to the conntrack ->packet() function, but the only user of this is the debug info decision. Same information can be derived from struct nf_conn. As a first step, add and use a new log function for this, similar to nf_ct_helper_log(). Add __cold annotation -- invalid packets should be infrequent so gcc can consider all call paths that lead to such a function as unlikely. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_proto.c | 24 ++++++++++++++++++++ net/netfilter/nf_conntrack_proto_dccp.c | 3 +-- net/netfilter/nf_conntrack_proto_sctp.c | 3 +-- net/netfilter/nf_conntrack_proto_tcp.c | 22 +++++++++--------- net/netfilter/nf_conntrack_proto_udp.c | 40 ++++++++++++++++----------------- 5 files changed, 55 insertions(+), 37 deletions(-) (limited to 'net/netfilter') diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c index b3e489c859ec..bcd3ee270d75 100644 --- a/net/netfilter/nf_conntrack_proto.c +++ b/net/netfilter/nf_conntrack_proto.c @@ -27,6 +27,7 @@ #include #include #include +#include static struct nf_conntrack_l4proto __rcu **nf_ct_protos[NFPROTO_NUMPROTO] __read_mostly; struct nf_conntrack_l3proto __rcu *nf_ct_l3protos[NFPROTO_NUMPROTO] __read_mostly; @@ -63,6 +64,29 @@ nf_ct_unregister_sysctl(struct ctl_table_header **header, *header = NULL; *table = NULL; } + +__printf(5, 6) +void nf_l4proto_log_invalid(const struct sk_buff *skb, + struct net *net, + u16 pf, u8 protonum, + const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + if (net->ct.sysctl_log_invalid != protonum || + net->ct.sysctl_log_invalid != IPPROTO_RAW) + return; + + va_start(args, fmt); + vaf.fmt = fmt; + vaf.va = &args; + + nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, + "nf_ct_proto_%d: %pV ", protonum, &vaf); + va_end(args); +} +EXPORT_SYMBOL_GPL(nf_l4proto_log_invalid); #endif const struct nf_conntrack_l4proto * diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c index 0f5a4d79f6b8..ef501c7edb96 100644 --- a/net/netfilter/nf_conntrack_proto_dccp.c +++ b/net/netfilter/nf_conntrack_proto_dccp.c @@ -604,8 +604,7 @@ static int dccp_error(struct net *net, struct nf_conn *tmpl, return NF_ACCEPT; out_invalid: - if (LOG_INVALID(net, IPPROTO_DCCP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, "%s", msg); + nf_l4proto_log_invalid(skb, net, pf, IPPROTO_DCCP, "%s", msg); return -NF_ACCEPT; } diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index 6303a88af12b..aa630c561361 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -522,8 +522,7 @@ static int sctp_error(struct net *net, struct nf_conn *tpl, struct sk_buff *skb, } return NF_ACCEPT; out_invalid: - if (LOG_INVALID(net, IPPROTO_SCTP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, "%s", logmsg); + nf_l4proto_log_invalid(skb, net, pf, IPPROTO_SCTP, "%s", logmsg); return -NF_ACCEPT; } diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c index cba1c6ffe51a..14198b2a2e2c 100644 --- a/net/netfilter/nf_conntrack_proto_tcp.c +++ b/net/netfilter/nf_conntrack_proto_tcp.c @@ -738,6 +738,12 @@ static const u8 tcp_valid_flags[(TCPHDR_FIN|TCPHDR_SYN|TCPHDR_RST|TCPHDR_ACK| [TCPHDR_ACK|TCPHDR_URG] = 1, }; +static void tcp_error_log(const struct sk_buff *skb, struct net *net, + u8 pf, const char *msg) +{ + nf_l4proto_log_invalid(skb, net, pf, IPPROTO_TCP, "%s", msg); +} + /* Protect conntrack agaist broken packets. Code taken from ipt_unclean.c. */ static int tcp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, @@ -753,17 +759,13 @@ static int tcp_error(struct net *net, struct nf_conn *tmpl, /* Smaller that minimal TCP header? */ th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph); if (th == NULL) { - if (LOG_INVALID(net, IPPROTO_TCP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_tcp: short packet "); + tcp_error_log(skb, net, pf, "short packet"); return -NF_ACCEPT; } /* Not whole TCP header or malformed packet */ if (th->doff*4 < sizeof(struct tcphdr) || tcplen < th->doff*4) { - if (LOG_INVALID(net, IPPROTO_TCP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_tcp: truncated/malformed packet "); + tcp_error_log(skb, net, pf, "truncated packet"); return -NF_ACCEPT; } @@ -774,18 +776,14 @@ static int tcp_error(struct net *net, struct nf_conn *tmpl, /* FIXME: Source route IP option packets --RR */ if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING && nf_checksum(skb, hooknum, dataoff, IPPROTO_TCP, pf)) { - if (LOG_INVALID(net, IPPROTO_TCP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_tcp: bad TCP checksum "); + tcp_error_log(skb, net, pf, "bad checksum"); return -NF_ACCEPT; } /* Check TCP flags. */ tcpflags = (tcp_flag_byte(th) & ~(TCPHDR_ECE|TCPHDR_CWR|TCPHDR_PSH)); if (!tcp_valid_flags[tcpflags]) { - if (LOG_INVALID(net, IPPROTO_TCP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_tcp: invalid TCP flag combination "); + tcp_error_log(skb, net, pf, "invalid tcp flag combination"); return -NF_ACCEPT; } diff --git a/net/netfilter/nf_conntrack_proto_udp.c b/net/netfilter/nf_conntrack_proto_udp.c index 8af734cd1a94..fc20cf430251 100644 --- a/net/netfilter/nf_conntrack_proto_udp.c +++ b/net/netfilter/nf_conntrack_proto_udp.c @@ -99,6 +99,12 @@ static bool udp_new(struct nf_conn *ct, const struct sk_buff *skb, } #ifdef CONFIG_NF_CT_PROTO_UDPLITE +static void udplite_error_log(const struct sk_buff *skb, struct net *net, + u8 pf, const char *msg) +{ + nf_l4proto_log_invalid(skb, net, pf, IPPROTO_UDPLITE, "%s", msg); +} + static int udplite_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, unsigned int dataoff, @@ -112,9 +118,7 @@ static int udplite_error(struct net *net, struct nf_conn *tmpl, /* Header is too small? */ hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr); if (!hdr) { - if (LOG_INVALID(net, IPPROTO_UDPLITE)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_udplite: short packet "); + udplite_error_log(skb, net, pf, "short packet"); return -NF_ACCEPT; } @@ -122,17 +126,13 @@ static int udplite_error(struct net *net, struct nf_conn *tmpl, if (cscov == 0) { cscov = udplen; } else if (cscov < sizeof(*hdr) || cscov > udplen) { - if (LOG_INVALID(net, IPPROTO_UDPLITE)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_udplite: invalid checksum coverage "); + udplite_error_log(skb, net, pf, "invalid checksum coverage"); return -NF_ACCEPT; } /* UDPLITE mandates checksums */ if (!hdr->check) { - if (LOG_INVALID(net, IPPROTO_UDPLITE)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_udplite: checksum missing "); + udplite_error_log(skb, net, pf, "checksum missing"); return -NF_ACCEPT; } @@ -140,9 +140,7 @@ static int udplite_error(struct net *net, struct nf_conn *tmpl, if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING && nf_checksum_partial(skb, hooknum, dataoff, cscov, IPPROTO_UDP, pf)) { - if (LOG_INVALID(net, IPPROTO_UDPLITE)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_udplite: bad UDPLite checksum "); + udplite_error_log(skb, net, pf, "bad checksum"); return -NF_ACCEPT; } @@ -150,6 +148,12 @@ static int udplite_error(struct net *net, struct nf_conn *tmpl, } #endif +static void udp_error_log(const struct sk_buff *skb, struct net *net, + u8 pf, const char *msg) +{ + nf_l4proto_log_invalid(skb, net, pf, IPPROTO_UDP, "%s", msg); +} + static int udp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, unsigned int dataoff, u_int8_t pf, @@ -162,17 +166,13 @@ static int udp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, /* Header is too small? */ hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr); if (hdr == NULL) { - if (LOG_INVALID(net, IPPROTO_UDP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_udp: short packet "); + udp_error_log(skb, net, pf, "short packet"); return -NF_ACCEPT; } /* Truncated/malformed packets */ if (ntohs(hdr->len) > udplen || ntohs(hdr->len) < sizeof(*hdr)) { - if (LOG_INVALID(net, IPPROTO_UDP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_udp: truncated/malformed packet "); + udp_error_log(skb, net, pf, "truncated/malformed packet"); return -NF_ACCEPT; } @@ -186,9 +186,7 @@ static int udp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, * FIXME: Source route IP option packets --RR */ if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING && nf_checksum(skb, hooknum, dataoff, IPPROTO_UDP, pf)) { - if (LOG_INVALID(net, IPPROTO_UDP)) - nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL, - "nf_ct_udp: bad UDP checksum "); + udp_error_log(skb, net, pf, "bad checksum"); return -NF_ACCEPT; } -- cgit v1.2.3