From 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Mon, 28 Jun 2010 14:16:08 +0200 Subject: netfilter: ipt_LOG/ip6t_LOG: add option to print decoded MAC header The LOG targets print the entire MAC header as one long string, which is not readable very well: IN=eth0 OUT= MAC=00:15:f2:24:91:f8:00:1b:24:dc:61:e6:08:00 ... Add an option to decode known header formats (currently just ARPHRD_ETHER devices) in their individual fields: IN=eth0 OUT= MACSRC=00:1b:24:dc:61:e6 MACDST=00:15:f2:24:91:f8 MACPROTO=0800 ... IN=eth0 OUT= MACSRC=00:1b:24:dc:61:e6 MACDST=00:15:f2:24:91:f8 MACPROTO=86dd ... The option needs to be explicitly enabled by userspace to avoid breaking existing parsers. Signed-off-by: Patrick McHardy --- net/ipv4/netfilter/ipt_LOG.c | 54 ++++++++++++++++++++++++++++++++------------ 1 file changed, 40 insertions(+), 14 deletions(-) (limited to 'net/ipv4/netfilter') diff --git a/net/ipv4/netfilter/ipt_LOG.c b/net/ipv4/netfilter/ipt_LOG.c index 0a452a5..915fc17 100644 --- a/net/ipv4/netfilter/ipt_LOG.c +++ b/net/ipv4/netfilter/ipt_LOG.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -363,6 +364,42 @@ static void dump_packet(const struct nf_loginfo *info, /* maxlen = 230+ 91 + 230 + 252 = 803 */ } +static void dump_mac_header(const struct nf_loginfo *info, + const struct sk_buff *skb) +{ + struct net_device *dev = skb->dev; + unsigned int logflags = 0; + + if (info->type == NF_LOG_TYPE_LOG) + logflags = info->u.log.logflags; + + if (!(logflags & IPT_LOG_MACDECODE)) + goto fallback; + + switch (dev->type) { + case ARPHRD_ETHER: + printk("MACSRC=%pM MACDST=%pM MACPROTO=%04x ", + eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest, + ntohs(eth_hdr(skb)->h_proto)); + return; + default: + break; + } + +fallback: + printk("MAC="); + if (dev->hard_header_len && + skb->mac_header != skb->network_header) { + const unsigned char *p = skb_mac_header(skb); + unsigned int i; + + printk("%02x", *p++); + for (i = 1; i < dev->hard_header_len; i++, p++) + printk(":%02x", *p); + } + printk(" "); +} + static struct nf_loginfo default_loginfo = { .type = NF_LOG_TYPE_LOG, .u = { @@ -404,20 +441,9 @@ ipt_log_packet(u_int8_t pf, } #endif - if (in && !out) { - /* MAC logging for input chain only. */ - printk("MAC="); - if (skb->dev && skb->dev->hard_header_len && - skb->mac_header != skb->network_header) { - int i; - const unsigned char *p = skb_mac_header(skb); - - printk("%02x", *p++); - for (i = 1; i < skb->dev->hard_header_len; i++, p++) - printk(":%02x", *p); - } - printk(" "); - } + /* MAC logging for input path only. */ + if (in && !out) + dump_mac_header(loginfo, skb); dump_packet(loginfo, skb, 0); printk("\n"); -- cgit v1.1