--- a/include/linux/netfilter/xt_layer7.h +++ b/include/linux/netfilter/xt_layer7.h @@ -8,6 +8,7 @@ struct xt_layer7_info { char protocol[MAX_PROTOCOL_LEN]; char pattern[MAX_PATTERN_LEN]; u_int8_t invert; + u_int8_t pkt; }; #endif /* _XT_LAYER7_H */ --- a/net/netfilter/xt_layer7.c +++ b/net/netfilter/xt_layer7.c @@ -314,33 +314,35 @@ static int match_no_append(struct nf_con } /* add the new app data to the conntrack. Return number of bytes added. */ -static int add_data(struct nf_conn * master_conntrack, - char * app_data, int appdatalen) +static int add_datastr(char *target, int offset, char *app_data, int len) { int length = 0, i; - int oldlength = master_conntrack->layer7.app_data_len; - - /* This is a fix for a race condition by Deti Fliegl. However, I'm not - clear on whether the race condition exists or whether this really - fixes it. I might just be being dense... Anyway, if it's not really - a fix, all it does is waste a very small amount of time. */ - if(!master_conntrack->layer7.app_data) return 0; + if (!target) return 0; /* Strip nulls. Make everything lower case (our regex lib doesn't do case insensitivity). Add it to the end of the current data. */ - for(i = 0; i < maxdatalen-oldlength-1 && - i < appdatalen; i++) { + for(i = 0; i < maxdatalen-offset-1 && i < len; i++) { if(app_data[i] != '\0') { /* the kernel version of tolower mungs 'upper ascii' */ - master_conntrack->layer7.app_data[length+oldlength] = + target[length+offset] = isascii(app_data[i])? tolower(app_data[i]) : app_data[i]; length++; } } + target[length+offset] = '\0'; + + return length; +} + +/* add the new app data to the conntrack. Return number of bytes added. */ +static int add_data(struct nf_conn * master_conntrack, + char * app_data, int appdatalen) +{ + int length; - master_conntrack->layer7.app_data[length+oldlength] = '\0'; - master_conntrack->layer7.app_data_len = length + oldlength; + length = add_datastr(master_conntrack->layer7.app_data, master_conntrack->layer7.app_data_len, app_data, appdatalen); + master_conntrack->layer7.app_data_len += length; return length; } @@ -428,7 +430,7 @@ match(const struct sk_buff *skbin, const struct xt_layer7_info * info = matchinfo; enum ip_conntrack_info master_ctinfo, ctinfo; struct nf_conn *master_conntrack, *conntrack; - unsigned char * app_data; + unsigned char *app_data, *tmp_data; unsigned int pattern_result, appdatalen; regexp * comppattern; @@ -456,8 +458,8 @@ match(const struct sk_buff *skbin, master_conntrack = master_ct(master_conntrack); /* if we've classified it or seen too many packets */ - if(total_acct_packets(master_conntrack) > num_packets || - master_conntrack->layer7.app_proto) { + if(!info->pkt && (total_acct_packets(master_conntrack) > num_packets || + master_conntrack->layer7.app_proto)) { pattern_result = match_no_append(conntrack, master_conntrack, ctinfo, master_ctinfo, info); @@ -490,6 +492,25 @@ match(const struct sk_buff *skbin, /* the return value gets checked later, when we're ready to use it */ comppattern = compile_and_cache(info->pattern, info->protocol); + if (info->pkt) { + tmp_data = kmalloc(maxdatalen, GFP_ATOMIC); + if(!tmp_data){ + if (net_ratelimit()) + printk(KERN_ERR "layer7: out of memory in match, bailing.\n"); + return info->invert; + } + + tmp_data[0] = '\0'; + add_datastr(tmp_data, 0, app_data, appdatalen); + pattern_result = ((comppattern && regexec(comppattern, tmp_data)) ? 1 : 0); + + kfree(tmp_data); + tmp_data = NULL; + spin_unlock_bh(&l7_lock); + + return (pattern_result ^ info->invert); + } + /* On the first packet of a connection, allocate space for app data */ if(total_acct_packets(master_conntrack) == 1 && !skb->cb[0] && !master_conntrack->layer7.app_data){