netfilter: accounting rework: ct_extend + 64bit counters (v4)

Initially netfilter has had 64bit counters for conntrack-based accounting, but
it was changed in 2.6.14 to save memory. Unfortunately in-kernel 64bit counters are
still required, for example for "connbytes" extension. However, 64bit counters
waste a lot of memory and it was not possible to enable/disable it runtime.

This patch:
 - reimplements accounting with respect to the extension infrastructure,
 - makes one global version of seq_print_acct() instead of two seq_print_counters(),
 - makes it possible to enable it at boot time (for CONFIG_SYSCTL/CONFIG_SYSFS=n),
 - makes it possible to enable/disable it at runtime by sysctl or sysfs,
 - extends counters from 32bit to 64bit,
 - renames ip_conntrack_counter -> nf_conn_counter,
 - enables accounting code unconditionally (no longer depends on CONFIG_NF_CT_ACCT),
 - set initial accounting enable state based on CONFIG_NF_CT_ACCT
 - removes buggy IPCT_COUNTER_FILLING event handling.

If accounting is enabled newly created connections get additional acct extend.
Old connections are not changed as it is not possible to add a ct_extend area
to confirmed conntrack. Accounting is performed for all connections with
acct extend regardless of a current state of "net.netfilter.nf_conntrack_acct".

Signed-off-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 15 deletions

diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c
index 40a46d48249..3a020720e40 100644
--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c
@@ -18,19 +18,7 @@
 #include <net/netfilter/nf_conntrack_l3proto.h>
 #include <net/netfilter/nf_conntrack_l4proto.h>
 #include <net/netfilter/nf_conntrack_expect.h>
-
-#ifdef CONFIG_NF_CT_ACCT
-static unsigned int
-seq_print_counters(struct seq_file *s,
-                   const struct ip_conntrack_counter *counter)
-{
-        return seq_printf(s, "packets=%llu bytes=%llu ",
-                          (unsigned long long)counter->packets,
-                          (unsigned long long)counter->bytes);
-}
-#else
-#define seq_print_counters(x, y)        0
-#endif
+#include <net/netfilter/nf_conntrack_acct.h>
 
 struct ct_iter_state {
         unsigned int bucket;
@@ -127,7 +115,7 @@ static int ct_seq_show(struct seq_file *s, void *v)
                         l3proto, l4proto))
                 return -ENOSPC;
 
-        if (seq_print_counters(s, &ct->counters[IP_CT_DIR_ORIGINAL]))
+        if (seq_print_acct(s, ct, IP_CT_DIR_ORIGINAL))
                 return -ENOSPC;
 
         if (!(test_bit(IPS_SEEN_REPLY_BIT, &ct->status)))
@@ -138,7 +126,7 @@ static int ct_seq_show(struct seq_file *s, void *v)
                         l3proto, l4proto))
                 return -ENOSPC;
 
-        if (seq_print_counters(s, &ct->counters[IP_CT_DIR_REPLY]))
+        if (seq_print_acct(s, ct, IP_CT_DIR_REPLY))
                 return -ENOSPC;
 
         if (test_bit(IPS_ASSURED_BIT, &ct->status))