xt_ipp2p: change text-search algo to KMP

The kernel's Boyer-Moore text-search implementation may miss matches in
non-linear skb's, so use Knuth-Morris-Pratt instead.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>

diff --git a/extensions/xt_ipp2p.c b/extensions/xt_ipp2p.c
index 2962909930df703563a5b320b75ce6c22fbe38b6..eba0b55812731cd2e518540ef2be63d13b7a7d9d 100644 (file)
--- a/extensions/xt_ipp2p.c
+++ b/extensions/xt_ipp2p.c
@@ -18,6 +18,8 @@
 #define get_u16(X, O)  get_unaligned((const __u16 *)((X) + O))
 #define get_u32(X, O)  get_unaligned((const __u32 *)((X) + O))
 
+#define TEXTSEARCH_ALGO "kmp"
+
 MODULE_AUTHOR("Eicke Friedrich/Klaus Degner <ipp2p@ipp2p.org>");
 MODULE_DESCRIPTION("An extension to iptables to identify P2P traffic.");
 MODULE_LICENSE("GPL");
@@ -1326,55 +1328,57 @@ static int ipp2p_mt_check(const struct xt_mtchk_param *par)
        struct ipt_p2p_info *info = par->matchinfo;
        struct ts_config *ts_conf;
 
-       ts_conf = textsearch_prepare("bm", "\x20\x22", 2,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO, "\x20\x22", 2,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_return;
        info->ts_conf_winmx = ts_conf;
 
-       ts_conf = textsearch_prepare("bm", "info_hash=", 10,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO, "info_hash=", 10,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_ts_destroy_winmx;
        info->ts_conf_bt_info_hash = ts_conf;
 
-       ts_conf = textsearch_prepare("bm", "peer_id=", 8,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO, "peer_id=", 8,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_ts_destroy_bt_info_hash;
        info->ts_conf_bt_peer_id = ts_conf;
 
-       ts_conf = textsearch_prepare("bm", "passkey", 8,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO, "passkey", 8,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_ts_destroy_bt_peer_id;
        info->ts_conf_bt_passkey = ts_conf;
 
-       ts_conf = textsearch_prepare("bm", "\r\nX-Gnutella-", 13,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO, "\r\nX-Gnutella-", 13,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_ts_destroy_bt_passkey;
        info->ts_conf_gnu_x_gnutella = ts_conf;
 
-       ts_conf = textsearch_prepare("bm", "\r\nX-Queue-", 10,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO, "\r\nX-Queue-", 10,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_ts_destroy_gnu_x_gnutella;
        info->ts_conf_gnu_x_queue = ts_conf;
 
-       ts_conf = textsearch_prepare("bm", "\r\nX-Kazaa-Username: ", 20,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO,
+                                    "\r\nX-Kazaa-Username: ", 20,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_ts_destroy_gnu_x_queue;
        info->ts_conf_kz_x_kazaa_username = ts_conf;
 
-       ts_conf = textsearch_prepare("bm", "\r\nUser-Agent: PeerEnabler/", 26,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO,
+                                    "\r\nUser-Agent: PeerEnabler/", 26,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_ts_destroy_kazaa_x_kazaa_username;
        info->ts_conf_kz_user_agent = ts_conf;
 
-       ts_conf = textsearch_prepare("bm", ":xdcc send #", 12,
+       ts_conf = textsearch_prepare(TEXTSEARCH_ALGO, ":xdcc send #", 12,
                                     GFP_KERNEL, TS_AUTOLOAD);
        if (IS_ERR(ts_conf))
                goto err_ts_destroy_kazaa_user_agent;