netfilter: xt_sctp: use WORD_ROUND macro to calculate length of multiple of 4 bytes

[net-next-2.6.git] / net / netfilter / xt_sctp.c

diff --git a/net/netfilter/xt_sctp.c b/net/netfilter/xt_sctp.c
index a189ada9128f523e9481f5c4d9c6c993c9574bad..ef36a56a02c6881c58296b2bf45c4b99d3836456 100644 (file)
--- a/net/netfilter/xt_sctp.c
+++ b/net/netfilter/xt_sctp.c
@@ -1,7 +1,9 @@
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 #include <linux/module.h>
 #include <linux/skbuff.h>
 #include <net/ip.h>
 #include <net/ipv6.h>
+#include <net/sctp/sctp.h>
 #include <linux/sctp.h>
 
 #include <linux/netfilter/x_tables.h>
@@ -15,12 +17,6 @@ MODULE_DESCRIPTION("Xtables: SCTP protocol packet match");
 MODULE_ALIAS("ipt_sctp");
 MODULE_ALIAS("ip6t_sctp");
 
-#ifdef DEBUG_SCTP
-#define duprintf(format, args...) printk(format , ## args)
-#else
-#define duprintf(format, args...)
-#endif
-
 #define SCCHECK(cond, option, flag, invflag) (!((flag) & (option)) \
                                              || (!!((invflag) & (option)) ^ (cond)))
 
@@ -52,7 +48,7 @@ match_packet(const struct sk_buff *skb,
        const struct xt_sctp_flag_info *flag_info = info->flag_info;
        int flag_count = info->flag_count;
 
-#ifdef DEBUG_SCTP
+#ifdef DEBUG
        int i = 0;
 #endif
 
@@ -62,17 +58,19 @@ match_packet(const struct sk_buff *skb,
        do {
                sch = skb_header_pointer(skb, offset, sizeof(_sch), &_sch);
                if (sch == NULL || sch->length == 0) {
-                       duprintf("Dropping invalid SCTP packet.\n");
+                       pr_debug("Dropping invalid SCTP packet.\n");
                        *hotdrop = true;
                        return false;
                }
+#ifdef DEBUG
+               pr_debug("Chunk num: %d\toffset: %d\ttype: %d\tlength: %d"
+                        "\tflags: %x\n",
+                        ++i, offset, sch->type, htons(sch->length),
+                        sch->flags);
+#endif
+               offset += WORD_ROUND(ntohs(sch->length));
 
-               duprintf("Chunk num: %d\toffset: %d\ttype: %d\tlength: %d\tflags: %x\n",
-                               ++i, offset, sch->type, htons(sch->length), sch->flags);
-
-               offset += (ntohs(sch->length) + 3) & ~3;
-
-               duprintf("skb->len: %d\toffset: %d\n", skb->len, offset);
+               pr_debug("skb->len: %d\toffset: %d\n", skb->len, offset);
 
                if (SCTP_CHUNKMAP_IS_SET(info->chunkmap, sch->type)) {
                        switch (chunk_match_type) {
@@ -117,24 +115,24 @@ match_packet(const struct sk_buff *skb,
 }
 
 static bool
-sctp_mt(const struct sk_buff *skb, const struct xt_match_param *par)
+sctp_mt(const struct sk_buff *skb, struct xt_action_param *par)
 {
        const struct xt_sctp_info *info = par->matchinfo;
        const sctp_sctphdr_t *sh;
        sctp_sctphdr_t _sh;
 
        if (par->fragoff != 0) {
-               duprintf("Dropping non-first fragment.. FIXME\n");
+               pr_debug("Dropping non-first fragment.. FIXME\n");
                return false;
        }
 
        sh = skb_header_pointer(skb, par->thoff, sizeof(_sh), &_sh);
        if (sh == NULL) {
-               duprintf("Dropping evil TCP offset=0 tinygram.\n");
-               *par->hotdrop = true;
+               pr_debug("Dropping evil TCP offset=0 tinygram.\n");
+               par->hotdrop = true;
                return false;
        }
-       duprintf("spt: %d\tdpt: %d\n", ntohs(sh->source), ntohs(sh->dest));
+       pr_debug("spt: %d\tdpt: %d\n", ntohs(sh->source), ntohs(sh->dest));
 
        return  SCCHECK(ntohs(sh->source) >= info->spts[0]
                        && ntohs(sh->source) <= info->spts[1],
@@ -143,22 +141,26 @@ sctp_mt(const struct sk_buff *skb, const struct xt_match_param *par)
                        && ntohs(sh->dest) <= info->dpts[1],
                        XT_SCTP_DEST_PORTS, info->flags, info->invflags)
                && SCCHECK(match_packet(skb, par->thoff + sizeof(sctp_sctphdr_t),
-                                       info, par->hotdrop),
+                                       info, &par->hotdrop),
                           XT_SCTP_CHUNK_TYPES, info->flags, info->invflags);
 }
 
-static bool sctp_mt_check(const struct xt_mtchk_param *par)
+static int sctp_mt_check(const struct xt_mtchk_param *par)
 {
        const struct xt_sctp_info *info = par->matchinfo;
 
-       return !(info->flags & ~XT_SCTP_VALID_FLAGS)
-               && !(info->invflags & ~XT_SCTP_VALID_FLAGS)
-               && !(info->invflags & ~info->flags)
-               && ((!(info->flags & XT_SCTP_CHUNK_TYPES)) ||
-                       (info->chunk_match_type &
-                               (SCTP_CHUNK_MATCH_ALL
-                               | SCTP_CHUNK_MATCH_ANY
-                               | SCTP_CHUNK_MATCH_ONLY)));
+       if (info->flags & ~XT_SCTP_VALID_FLAGS)
+               return -EINVAL;
+       if (info->invflags & ~XT_SCTP_VALID_FLAGS)
+               return -EINVAL;
+       if (info->invflags & ~info->flags)
+               return -EINVAL;
+       if (!(info->flags & XT_SCTP_CHUNK_TYPES))
+               return 0;
+       if (info->chunk_match_type & (SCTP_CHUNK_MATCH_ALL |
+           SCTP_CHUNK_MATCH_ANY | SCTP_CHUNK_MATCH_ONLY))
+               return 0;
+       return -EINVAL;
 }
 
 static struct xt_match sctp_mt_reg[] __read_mostly = {