netfilter: restore rule tracing via nfnetlink_log

Since fab4085 ("netfilter: log: nf_log_packet() as real unified
interface"), the loginfo structure that is passed to nf_log_packet() is
used to explicitly indicate the logger type you want to use.

This is a problem for people tracing rules through nfnetlink_log since
packets are always routed to the NF_LOG_TYPE logger after the
aforementioned patch.

We can fix this by removing the trace loginfo structures, but that still
changes the log level from 4 to 5 for tracing messages and there may be
someone relying on this outthere. So let's just introduce a new
nf_log_trace() function that restores the former behaviour.

Reported-by: Markus Kötter <koetter@rrzn.uni-hannover.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/net/netfilter/nf_log.h b/include/net/netfilter/nf_log.h
index 534e1f2..57639fc 100644 (file)
--- a/include/net/netfilter/nf_log.h
+++ b/include/net/netfilter/nf_log.h
@@ -79,6 +79,16 @@ void nf_log_packet(struct net *net,
                   const struct nf_loginfo *li,
                   const char *fmt, ...);
 
+__printf(8, 9)
+void nf_log_trace(struct net *net,
+                 u_int8_t pf,
+                 unsigned int hooknum,
+                 const struct sk_buff *skb,
+                 const struct net_device *in,
+                 const struct net_device *out,
+                 const struct nf_loginfo *li,
+                 const char *fmt, ...);
+
 struct nf_log_buf;
 
 struct nf_log_buf *nf_log_buf_open(void);

diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 99e810f..cf5e82f 100644 (file)
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -272,9 +272,9 @@ static void trace_packet(const struct sk_buff *skb,
                    &chainname, &comment, &rulenum) != 0)
                        break;
 
-       nf_log_packet(net, AF_INET, hook, skb, in, out, &trace_loginfo,
-                     "TRACE: %s:%s:%s:%u ",
-                     tablename, chainname, comment, rulenum);
+       nf_log_trace(net, AF_INET, hook, skb, in, out, &trace_loginfo,
+                    "TRACE: %s:%s:%s:%u ",
+                    tablename, chainname, comment, rulenum);
 }
 #endif
 

diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index e080fbb..bb00c6f 100644 (file)
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -298,9 +298,9 @@ static void trace_packet(const struct sk_buff *skb,
                    &chainname, &comment, &rulenum) != 0)
                        break;
 
-       nf_log_packet(net, AF_INET6, hook, skb, in, out, &trace_loginfo,
-                     "TRACE: %s:%s:%s:%u ",
-                     tablename, chainname, comment, rulenum);
+       nf_log_trace(net, AF_INET6, hook, skb, in, out, &trace_loginfo,
+                    "TRACE: %s:%s:%s:%u ",
+                    tablename, chainname, comment, rulenum);
 }
 #endif
 

diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index 0d8448f..675d12c 100644 (file)
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -212,6 +212,30 @@ void nf_log_packet(struct net *net,
 }
 EXPORT_SYMBOL(nf_log_packet);
 
+void nf_log_trace(struct net *net,
+                 u_int8_t pf,
+                 unsigned int hooknum,
+                 const struct sk_buff *skb,
+                 const struct net_device *in,
+                 const struct net_device *out,
+                 const struct nf_loginfo *loginfo, const char *fmt, ...)
+{
+       va_list args;
+       char prefix[NF_LOG_PREFIXLEN];
+       const struct nf_logger *logger;
+
+       rcu_read_lock();
+       logger = rcu_dereference(net->nf.nf_loggers[pf]);
+       if (logger) {
+               va_start(args, fmt);
+               vsnprintf(prefix, sizeof(prefix), fmt, args);
+               va_end(args);
+               logger->logfn(net, pf, hooknum, skb, in, out, loginfo, prefix);
+       }
+       rcu_read_unlock();
+}
+EXPORT_SYMBOL(nf_log_trace);
+
 #define S_SIZE (1024 - (sizeof(unsigned int) + 1))
 
 struct nf_log_buf {

diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
index 3b90eb2..2d298dc 100644 (file)
--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -94,10 +94,10 @@ static void nft_trace_packet(const struct nft_pktinfo *pkt,
 {
        struct net *net = dev_net(pkt->in ? pkt->in : pkt->out);
 
-       nf_log_packet(net, pkt->xt.family, pkt->ops->hooknum, pkt->skb, pkt->in,
-                     pkt->out, &trace_loginfo, "TRACE: %s:%s:%s:%u ",
-                     chain->table->name, chain->name, comments[type],
-                     rulenum);
+       nf_log_trace(net, pkt->xt.family, pkt->ops->hooknum, pkt->skb, pkt->in,
+                    pkt->out, &trace_loginfo, "TRACE: %s:%s:%s:%u ",
+                    chain->table->name, chain->name, comments[type],
+                    rulenum);
 }
 
 unsigned int