lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

netfilter: ipt_LOG: add bufferisation to call printk() once

Browse Source 
ipt_LOG & ip6t_LOG use lot of calls to printk() and use a lock in a hope
several cpus wont mix their output in syslog.

printk() being very expensive [1], its better to call it once, on a
prebuilt and complete line. Also, with mixed IPv4 and IPv6 trafic,
separate IPv4/IPv6 locks dont avoid garbage.

I used an allocation of a 1024 bytes structure, sort of seq_printf() but
with a fixed size limit.
Use a static buffer if dynamic allocation failed.

Emit a once time alert if buffer size happens to be too short.

[1]: printk() has various features like printk_delay()...

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This commit is contained in:
Eric Dumazet
2010-10-04 20:56:05 +02:00
committed by Patrick McHardy
parent 0c200d9353
commit a8defca048
2 changed files with 152 additions and 150 deletions
Download Patch File Download Diff File Expand all files Collapse all files

157
net/ipv6/netfilter/ip6t_LOG.c
View File

@@ -23,6 +23,7 @@
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <net/netfilter/nf_log.h>
#include <net/netfilter/xt_log.h>
MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>");
MODULE_DESCRIPTION("Xtables: IPv6 packet logging to syslog");
@@ -32,11 +33,9 @@ struct in_device;
#include <net/route.h>
#include <linux/netfilter_ipv6/ip6t_LOG.h>
/* Use lock to serialize, so printks don't overlap */
static DEFINE_SPINLOCK(log_lock);
/* One level of recursion won't kill us */
static void dump_packet(const struct nf_loginfo *info,
static void dump_packet(struct sbuff *m,
const struct nf_loginfo *info,
const struct sk_buff *skb, unsigned int ip6hoff,
int recurse)
{
@@ -55,15 +54,15 @@ static void dump_packet(const struct nf_loginfo *info,
ih = skb_header_pointer(skb, ip6hoff, sizeof(_ip6h), &_ip6h);
if (ih == NULL) {
printk("TRUNCATED");
sb_add(m, "TRUNCATED");
return;
}
/* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000 " */
printk("SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr);
sb_add(m, "SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr);
/* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */
printk("LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
sb_add(m, "LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
ntohs(ih->payload_len) + sizeof(struct ipv6hdr),
(ntohl(*(__be32 *)ih) & 0x0ff00000) >> 20,
ih->hop_limit,
@@ -78,35 +77,35 @@ static void dump_packet(const struct nf_loginfo *info,
hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
if (hp == NULL) {
printk("TRUNCATED");
sb_add(m, "TRUNCATED");
return;
}
/* Max length: 48 "OPT (...) " */
if (logflags & IP6T_LOG_IPOPT)
printk("OPT ( ");
sb_add(m, "OPT ( ");
switch (currenthdr) {
case IPPROTO_FRAGMENT: {
struct frag_hdr _fhdr;
const struct frag_hdr *fh;
printk("FRAG:");
sb_add(m, "FRAG:");
fh = skb_header_pointer(skb, ptr, sizeof(_fhdr),
&_fhdr);
if (fh == NULL) {
printk("TRUNCATED ");
sb_add(m, "TRUNCATED ");
return;
}
/* Max length: 6 "65535 " */
printk("%u ", ntohs(fh->frag_off) & 0xFFF8);
sb_add(m, "%u ", ntohs(fh->frag_off) & 0xFFF8);
/* Max length: 11 "INCOMPLETE " */
if (fh->frag_off & htons(0x0001))
printk("INCOMPLETE ");
sb_add(m, "INCOMPLETE ");
printk("ID:%08x ", ntohl(fh->identification));
sb_add(m, "ID:%08x ", ntohl(fh->identification));
if (ntohs(fh->frag_off) & 0xFFF8)
fragment = 1;
@@ -120,7 +119,7 @@ static void dump_packet(const struct nf_loginfo *info,
case IPPROTO_HOPOPTS:
if (fragment) {
if (logflags & IP6T_LOG_IPOPT)
printk(")");
sb_add(m, ")");
return;
}
hdrlen = ipv6_optlen(hp);
@@ -132,10 +131,10 @@ static void dump_packet(const struct nf_loginfo *info,
const struct ip_auth_hdr *ah;
/* Max length: 3 "AH " */
printk("AH ");
sb_add(m, "AH ");
if (fragment) {
printk(")");
sb_add(m, ")");
return;
}
@@ -146,13 +145,13 @@ static void dump_packet(const struct nf_loginfo *info,
* Max length: 26 "INCOMPLETE [65535
* bytes] )"
*/
printk("INCOMPLETE [%u bytes] )",
sb_add(m, "INCOMPLETE [%u bytes] )",
skb->len - ptr);
return;
}
/* Length: 15 "SPI=0xF1234567 */
printk("SPI=0x%x ", ntohl(ah->spi));
sb_add(m, "SPI=0x%x ", ntohl(ah->spi));
}
@@ -164,10 +163,10 @@ static void dump_packet(const struct nf_loginfo *info,
const struct ip_esp_hdr *eh;
/* Max length: 4 "ESP " */
printk("ESP ");
sb_add(m, "ESP ");
if (fragment) {
printk(")");
sb_add(m, ")");
return;
}
@@ -177,23 +176,23 @@ static void dump_packet(const struct nf_loginfo *info,
eh = skb_header_pointer(skb, ptr, sizeof(_esph),
&_esph);
if (eh == NULL) {
printk("INCOMPLETE [%u bytes] )",
sb_add(m, "INCOMPLETE [%u bytes] )",
skb->len - ptr);
return;
}
/* Length: 16 "SPI=0xF1234567 )" */
printk("SPI=0x%x )", ntohl(eh->spi) );
sb_add(m, "SPI=0x%x )", ntohl(eh->spi) );
}
return;
default:
/* Max length: 20 "Unknown Ext Hdr 255" */
printk("Unknown Ext Hdr %u", currenthdr);
sb_add(m, "Unknown Ext Hdr %u", currenthdr);
return;
}
if (logflags & IP6T_LOG_IPOPT)
printk(") ");
sb_add(m, ") ");
currenthdr = hp->nexthdr;
ptr += hdrlen;
@@ -205,7 +204,7 @@ static void dump_packet(const struct nf_loginfo *info,
const struct tcphdr *th;
/* Max length: 10 "PROTO=TCP " */
printk("PROTO=TCP ");
sb_add(m, "PROTO=TCP ");
if (fragment)
break;
@@ -213,40 +212,40 @@ static void dump_packet(const struct nf_loginfo *info,
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
th = skb_header_pointer(skb, ptr, sizeof(_tcph), &_tcph);
if (th == NULL) {
printk("INCOMPLETE [%u bytes] ", skb->len - ptr);
sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - ptr);
return;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
printk("SPT=%u DPT=%u ",
sb_add(m, "SPT=%u DPT=%u ",
ntohs(th->source), ntohs(th->dest));
/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
if (logflags & IP6T_LOG_TCPSEQ)
printk("SEQ=%u ACK=%u ",
sb_add(m, "SEQ=%u ACK=%u ",
ntohl(th->seq), ntohl(th->ack_seq));
/* Max length: 13 "WINDOW=65535 " */
printk("WINDOW=%u ", ntohs(th->window));
sb_add(m, "WINDOW=%u ", ntohs(th->window));
/* Max length: 9 "RES=0x3C " */
printk("RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) & TCP_RESERVED_BITS) >> 22));
sb_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) & TCP_RESERVED_BITS) >> 22));
/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
if (th->cwr)
printk("CWR ");
sb_add(m, "CWR ");
if (th->ece)
printk("ECE ");
sb_add(m, "ECE ");
if (th->urg)
printk("URG ");
sb_add(m, "URG ");
if (th->ack)
printk("ACK ");
sb_add(m, "ACK ");
if (th->psh)
printk("PSH ");
sb_add(m, "PSH ");
if (th->rst)
printk("RST ");
sb_add(m, "RST ");
if (th->syn)
printk("SYN ");
sb_add(m, "SYN ");
if (th->fin)
printk("FIN ");
sb_add(m, "FIN ");
/* Max length: 11 "URGP=65535 " */
printk("URGP=%u ", ntohs(th->urg_ptr));
sb_add(m, "URGP=%u ", ntohs(th->urg_ptr));
if ((logflags & IP6T_LOG_TCPOPT) &&
th->doff * 4 > sizeof(struct tcphdr)) {
@@ -260,15 +259,15 @@ static void dump_packet(const struct nf_loginfo *info,
ptr + sizeof(struct tcphdr),
optsize, _opt);
if (op == NULL) {
printk("OPT (TRUNCATED)");
sb_add(m, "OPT (TRUNCATED)");
return;
}
/* Max length: 127 "OPT (" 15*4*2chars ") " */
printk("OPT (");
sb_add(m, "OPT (");
for (i =0; i < optsize; i++)
printk("%02X", op[i]);
printk(") ");
sb_add(m, "%02X", op[i]);
sb_add(m, ") ");
}
break;
}
@@ -279,9 +278,9 @@ static void dump_packet(const struct nf_loginfo *info,
if (currenthdr == IPPROTO_UDP)
/* Max length: 10 "PROTO=UDP " */
printk("PROTO=UDP " );
sb_add(m, "PROTO=UDP " );
else /* Max length: 14 "PROTO=UDPLITE " */
printk("PROTO=UDPLITE ");
sb_add(m, "PROTO=UDPLITE ");
if (fragment)
break;
@@ -289,12 +288,12 @@ static void dump_packet(const struct nf_loginfo *info,
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
uh = skb_header_pointer(skb, ptr, sizeof(_udph), &_udph);
if (uh == NULL) {
printk("INCOMPLETE [%u bytes] ", skb->len - ptr);
sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - ptr);
return;
}
/* Max length: 20 "SPT=65535 DPT=65535 " */
printk("SPT=%u DPT=%u LEN=%u ",
sb_add(m, "SPT=%u DPT=%u LEN=%u ",
ntohs(uh->source), ntohs(uh->dest),
ntohs(uh->len));
break;
@@ -304,7 +303,7 @@ static void dump_packet(const struct nf_loginfo *info,
const struct icmp6hdr *ic;
/* Max length: 13 "PROTO=ICMPv6 " */
printk("PROTO=ICMPv6 ");
sb_add(m, "PROTO=ICMPv6 ");
if (fragment)
break;
@@ -312,18 +311,18 @@ static void dump_packet(const struct nf_loginfo *info,
/* Max length: 25 "INCOMPLETE [65535 bytes] " */
ic = skb_header_pointer(skb, ptr, sizeof(_icmp6h), &_icmp6h);
if (ic == NULL) {
printk("INCOMPLETE [%u bytes] ", skb->len - ptr);
sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - ptr);
return;
}
/* Max length: 18 "TYPE=255 CODE=255 " */
printk("TYPE=%u CODE=%u ", ic->icmp6_type, ic->icmp6_code);
sb_add(m, "TYPE=%u CODE=%u ", ic->icmp6_type, ic->icmp6_code);
switch (ic->icmp6_type) {
case ICMPV6_ECHO_REQUEST:
case ICMPV6_ECHO_REPLY:
/* Max length: 19 "ID=65535 SEQ=65535 " */
printk("ID=%u SEQ=%u ",
sb_add(m, "ID=%u SEQ=%u ",
ntohs(ic->icmp6_identifier),
ntohs(ic->icmp6_sequence));
break;
@@ -334,35 +333,35 @@ static void dump_packet(const struct nf_loginfo *info,
case ICMPV6_PARAMPROB:
/* Max length: 17 "POINTER=ffffffff " */
printk("POINTER=%08x ", ntohl(ic->icmp6_pointer));
sb_add(m, "POINTER=%08x ", ntohl(ic->icmp6_pointer));
/* Fall through */
case ICMPV6_DEST_UNREACH:
case ICMPV6_PKT_TOOBIG:
case ICMPV6_TIME_EXCEED:
/* Max length: 3+maxlen */
if (recurse) {
printk("[");
dump_packet(info, skb, ptr + sizeof(_icmp6h),
0);
printk("] ");
sb_add(m, "[");
dump_packet(m, info, skb,
ptr + sizeof(_icmp6h), 0);
sb_add(m, "] ");
}
/* Max length: 10 "MTU=65535 " */
if (ic->icmp6_type == ICMPV6_PKT_TOOBIG)
printk("MTU=%u ", ntohl(ic->icmp6_mtu));
sb_add(m, "MTU=%u ", ntohl(ic->icmp6_mtu));
}
break;
}
/* Max length: 10 "PROTO=255 " */
default:
printk("PROTO=%u ", currenthdr);
sb_add(m, "PROTO=%u ", currenthdr);
}
/* Max length: 15 "UID=4294967295 " */
if ((logflags & IP6T_LOG_UID) && recurse && skb->sk) {
read_lock_bh(&skb->sk->sk_callback_lock);
if (skb->sk->sk_socket && skb->sk->sk_socket->file)
printk("UID=%u GID=%u ",
sb_add(m, "UID=%u GID=%u ",
skb->sk->sk_socket->file->f_cred->fsuid,
skb->sk->sk_socket->file->f_cred->fsgid);
read_unlock_bh(&skb->sk->sk_callback_lock);
@@ -370,10 +369,11 @@ static void dump_packet(const struct nf_loginfo *info,
/* Max length: 16 "MARK=0xFFFFFFFF " */
if (!recurse && skb->mark)
printk("MARK=0x%x ", skb->mark);
sb_add(m, "MARK=0x%x ", skb->mark);
}
static void dump_mac_header(const struct nf_loginfo *info,
static void dump_mac_header(struct sbuff *m,
const struct nf_loginfo *info,
const struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
@@ -387,7 +387,7 @@ static void dump_mac_header(const struct nf_loginfo *info,
switch (dev->type) {
case ARPHRD_ETHER:
printk("MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
sb_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
ntohs(eth_hdr(skb)->h_proto));
return;
@@ -396,7 +396,7 @@ static void dump_mac_header(const struct nf_loginfo *info,
}
fallback:
printk("MAC=");
sb_add(m, "MAC=");
if (dev->hard_header_len &&
skb->mac_header != skb->network_header) {
const unsigned char *p = skb_mac_header(skb);
@@ -408,19 +408,19 @@ fallback:
p = NULL;
if (p != NULL) {
printk("%02x", *p++);
sb_add(m, "%02x", *p++);
for (i = 1; i < len; i++)
printk(":%02x", p[i]);
sb_add(m, ":%02x", p[i]);
}
printk(" ");
sb_add(m, " ");
if (dev->type == ARPHRD_SIT) {
const struct iphdr *iph =
(struct iphdr *)skb_mac_header(skb);
printk("TUNNEL=%pI4->%pI4 ", &iph->saddr, &iph->daddr);
sb_add(m, "TUNNEL=%pI4->%pI4 ", &iph->saddr, &iph->daddr);
}
} else
printk(" ");
sb_add(m, " ");
}
static struct nf_loginfo default_loginfo = {
@@ -442,22 +442,23 @@ ip6t_log_packet(u_int8_t pf,
const struct nf_loginfo *loginfo,
const char *prefix)
{
struct sbuff *m = sb_open();
if (!loginfo)
loginfo = &default_loginfo;
spin_lock_bh(&log_lock);
printk("<%d>%sIN=%s OUT=%s ", loginfo->u.log.level,
prefix,
in ? in->name : "",
out ? out->name : "");
sb_add(m, "<%d>%sIN=%s OUT=%s ", loginfo->u.log.level,
prefix,
in ? in->name : "",
out ? out->name : "");
/* MAC logging for input path only. */
if (in && !out)
dump_mac_header(loginfo, skb);
dump_mac_header(m, loginfo, skb);
dump_packet(loginfo, skb, skb_network_offset(skb), 1);
printk("\n");
spin_unlock_bh(&log_lock);
dump_packet(m, loginfo, skb, skb_network_offset(skb), 1);
sb_close(m);
}
static unsigned int