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--- 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;
}
@@ -438,7 +440,7 @@ match(const struct sk_buff *skbin,
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;
@@ -466,8 +468,8 @@ 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);
@@ -500,6 +502,25 @@ 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){
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