target/linux/generic-2.6/patches-2.6.22/101-netfilter_layer7_pktmatch.patch

   1 diff -urN linux-2.6.21.1.old/include/linux/netfilter_ipv4/ipt_layer7.h linux-2.6.21.1.dev/include/linux/netfilter_ipv4/ipt_layer7.h
   2 --- linux-2.6.21.1.old/include/linux/netfilter_ipv4/ipt_layer7.h        2007-05-26 20:17:47.624408296 +0200
   3 +++ linux-2.6.21.1.dev/include/linux/netfilter_ipv4/ipt_layer7.h        2007-05-26 20:17:48.729240336 +0200
   4 @@ -21,6 +21,7 @@
   5      char protocol[MAX_PROTOCOL_LEN];
   6      char invert:1;
   7      char pattern[MAX_PATTERN_LEN];
   8 +    char pkt;
   9  };
  10
  11  #endif /* _IPT_LAYER7_H */
  12 diff -urN linux-2.6.21.1.old/net/ipv4/netfilter/ipt_layer7.c linux-2.6.21.1.dev/net/ipv4/netfilter/ipt_layer7.c
  13 --- linux-2.6.21.1.old/net/ipv4/netfilter/ipt_layer7.c  2007-05-26 20:17:47.626407992 +0200
  14 +++ linux-2.6.21.1.dev/net/ipv4/netfilter/ipt_layer7.c  2007-05-26 20:17:48.729240336 +0200
  15 @@ -296,33 +296,34 @@
  16         }
  17  }
  18
  19 -/* add the new app data to the conntrack.  Return number of bytes added. */
  20 -static int add_data(struct ip_conntrack * master_conntrack,
  21 -                       char * app_data, int appdatalen)
  22 +static int add_datastr(char *target, int offset, char *app_data, int len)
  23  {
  24         int length = 0, i;
  25 -       int oldlength = master_conntrack->layer7.app_data_len;
  26 -
  27 -       // This is a fix for a race condition by Deti Fliegl. However, I'm not
  28 -       // clear on whether the race condition exists or whether this really
  29 -       // fixes it.  I might just be being dense... Anyway, if it's not really
  30 -       // a fix, all it does is waste a very small amount of time.
  31 -       if(!master_conntrack->layer7.app_data) return 0;
  32 +       if(!target) return 0;
  33
  34         /* Strip nulls. Make everything lower case (our regex lib doesn't
  35         do case insensitivity).  Add it to the end of the current data. */
  36 -       for(i = 0; i < maxdatalen-oldlength-1 &&
  37 -                  i < appdatalen; i++) {
  38 +       for(i = 0; i < maxdatalen-offset-1 && i < len; i++) {
  39                 if(app_data[i] != '\0') {
  40 -                       master_conntrack->layer7.app_data[length+oldlength] =
  41 +                       target[length+offset] =
  42                                 /* the kernel version of tolower mungs 'upper ascii' */
  43                                 isascii(app_data[i])? tolower(app_data[i]) : app_data[i];
  44                         length++;
  45                 }
  46         }
  47 +       target[length+offset] = '\0';
  48
  49 -       master_conntrack->layer7.app_data[length+oldlength] = '\0';
  50 -       master_conntrack->layer7.app_data_len = length + oldlength;
  51 +       return length;
  52 +}
  53 +
  54 +/* add the new app data to the conntrack.  Return number of bytes added. */
  55 +static int add_data(struct ip_conntrack * master_conntrack,
  56 +                       char * app_data, int appdatalen)
  57 +{
  58 +       int length;
  59 +
  60 +       length = add_datastr(master_conntrack->layer7.app_data, master_conntrack->layer7.app_data_len, app_data, appdatalen);
  61 +       master_conntrack->layer7.app_data_len += length;
  62
  63         return length;
  64  }
  65 @@ -339,7 +340,7 @@
  66         struct ipt_layer7_info * info = (struct ipt_layer7_info *)matchinfo;
  67         enum ip_conntrack_info master_ctinfo, ctinfo;
  68         struct ip_conntrack *master_conntrack, *conntrack;
  69 -       unsigned char * app_data;
  70 +       unsigned char *app_data, *tmp_data;
  71         unsigned int pattern_result, appdatalen;
  72         regexp * comppattern;
  73
  74 @@ -362,8 +363,8 @@
  75                 master_conntrack = master_ct(master_conntrack);
  76
  77         /* if we've classified it or seen too many packets */
  78 -       if(TOTAL_PACKETS > num_packets ||
  79 -          master_conntrack->layer7.app_proto) {
  80 +       if(!info->pkt && (TOTAL_PACKETS > num_packets ||
  81 +               master_conntrack->layer7.app_proto)) {
  82
  83                 pattern_result = match_no_append(conntrack, master_conntrack, ctinfo, master_ctinfo, info);
  84
  85 @@ -394,6 +395,23 @@
  86         comppattern = compile_and_cache(info->pattern, info->protocol);
  87         spin_unlock_bh(&list_lock);
  88
  89 +       if (info->pkt) {
  90 +               tmp_data = kmalloc(maxdatalen, GFP_ATOMIC);
  91 +               if(!tmp_data){
  92 +                       if (net_ratelimit())
  93 +                               printk(KERN_ERR "layer7: out of memory in match, bailing.\n");
  94 +                       return info->invert;
  95 +               }
  96 +
  97 +               tmp_data[0] = '\0';
  98 +               add_datastr(tmp_data, 0, app_data, appdatalen);
  99 +               pattern_result = ((comppattern && regexec(comppattern, tmp_data)) ? 1 : 0);
 100 +               kfree(tmp_data);
 101 +               tmp_data = NULL;
 102 +
 103 +               return (pattern_result ^ info->invert);
 104 +       }
 105 +
 106         /* On the first packet of a connection, allocate space for app data */
 107         write_lock(&ct_lock);
 108         if(TOTAL_PACKETS == 1 && !skb->cb[0] && !master_conntrack->layer7.app_data) {