X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=net%2Fipv6%2Fnetfilter%2Fip6t_hbh.c;h=374f1be85c0d41a3c18d843e030c476bff041268;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=6849122c37e9cb36988c9d7adb1c970a5dce30c0;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git

diff --git a/net/ipv6/netfilter/ip6t_hbh.c b/net/ipv6/netfilter/ip6t_hbh.c
index 6849122c3..374f1be85 100644
--- a/net/ipv6/netfilter/ip6t_hbh.c
+++ b/net/ipv6/netfilter/ip6t_hbh.c
@@ -19,8 +19,6 @@
 #include <linux/netfilter_ipv6/ip6_tables.h>
 #include <linux/netfilter_ipv6/ip6t_opts.h>
 
-#define LOW(n)		(n & 0x00FF)
-
 #define HOPBYHOP	1
 
 MODULE_LICENSE("GPL");
@@ -38,201 +36,141 @@ MODULE_AUTHOR("Andras Kis-Szabo <kisza@sch.bme.hu>");
 #endif
 
 /*
- * (Type & 0xC0) >> 6
- * 	0	-> ignorable
- * 	1	-> must drop the packet
- * 	2	-> send ICMP PARM PROB regardless and drop packet
- * 	3	-> Send ICMP if not a multicast address and drop packet
+ *  (Type & 0xC0) >> 6
+ *	0	-> ignorable
+ *	1	-> must drop the packet
+ *	2	-> send ICMP PARM PROB regardless and drop packet
+ *	3	-> Send ICMP if not a multicast address and drop packet
  *  (Type & 0x20) >> 5
- *  	0	-> invariant
- *  	1	-> can change the routing
+ *	0	-> invariant
+ *	1	-> can change the routing
  *  (Type & 0x1F) Type
- *      0	-> PAD0 (only 1 byte!)
- *      1	-> PAD1 LENGTH info (total length = length + 2)
- *      C0 | 2	-> JUMBO 4 x x x x ( xxxx > 64k )
- *      5	-> RTALERT 2 x x
+ *	0	-> Pad1 (only 1 byte!)
+ *	1	-> PadN LENGTH info (total length = length + 2)
+ *	C0 | 2	-> JUMBO 4 x x x x ( xxxx > 64k )
+ *	5	-> RTALERT 2 x x
  */
 
 static int
 match(const struct sk_buff *skb,
       const struct net_device *in,
       const struct net_device *out,
+      const struct xt_match *match,
       const void *matchinfo,
       int offset,
-      const void *protohdr,
-      u_int16_t datalen,
+      unsigned int protoff,
       int *hotdrop)
 {
-       struct ipv6_opt_hdr *optsh = NULL;
-       const struct ip6t_opts *optinfo = matchinfo;
-       unsigned int temp;
-       unsigned int len;
-       u8 nexthdr;
-       unsigned int ptr;
-       unsigned int hdrlen = 0;
-       unsigned int ret = 0;
-       u_int16_t *optdesc = NULL;
-       
-       /* type of the 1st exthdr */
-       nexthdr = skb->nh.ipv6h->nexthdr;
-       /* pointer to the 1st exthdr */
-       ptr = sizeof(struct ipv6hdr);
-       /* available length */
-       len = skb->len - ptr;
-       temp = 0;
-
-        while (ip6t_ext_hdr(nexthdr)) {
-               struct ipv6_opt_hdr *hdr;
-
-              DEBUGP("ipv6_opts header iteration \n");
-
-              /* Is there enough space for the next ext header? */
-                if (len < (int)sizeof(struct ipv6_opt_hdr))
-                        return 0;
-              /* No more exthdr -> evaluate */
-                if (nexthdr == NEXTHDR_NONE) {
-                     break;
-              }
-              /* ESP -> evaluate */
-                if (nexthdr == NEXTHDR_ESP) {
-                     break;
-              }
-
-              hdr=(void *)(skb->data)+ptr;
-
-              /* Calculate the header length */
-                if (nexthdr == NEXTHDR_FRAGMENT) {
-                        hdrlen = 8;
-                } else if (nexthdr == NEXTHDR_AUTH)
-                        hdrlen = (hdr->hdrlen+2)<<2;
-                else
-                        hdrlen = ipv6_optlen(hdr);
-
-              /* OPTS -> evaluate */
-#if HOPBYHOP
-                if (nexthdr == NEXTHDR_HOP) {
-                     temp |= MASK_HOPOPTS;
-#else
-                if (nexthdr == NEXTHDR_DEST) {
-                     temp |= MASK_DSTOPTS;
-#endif
-                     break;
-              }
-
-
-              /* set the flag */
-              switch (nexthdr){
-                     case NEXTHDR_HOP:
-                     case NEXTHDR_ROUTING:
-                     case NEXTHDR_FRAGMENT:
-                     case NEXTHDR_AUTH:
-                     case NEXTHDR_DEST:
-                            break;
-                     default:
-                            DEBUGP("ipv6_opts match: unknown nextheader %u\n",nexthdr);
-                            return 0;
-                            break;
-              }
-
-                nexthdr = hdr->nexthdr;
-                len -= hdrlen;
-                ptr += hdrlen;
-		if ( ptr > skb->len ) {
-			DEBUGP("ipv6_opts: new pointer is too large! \n");
-			break;
-		}
-        }
+	struct ipv6_opt_hdr _optsh, *oh;
+	const struct ip6t_opts *optinfo = matchinfo;
+	unsigned int temp;
+	unsigned int ptr;
+	unsigned int hdrlen = 0;
+	unsigned int ret = 0;
+	u8 _opttype, *tp = NULL;
+	u8 _optlen, *lp = NULL;
+	unsigned int optlen;
 
-       /* OPTIONS header not found */
 #if HOPBYHOP
-       if ( temp != MASK_HOPOPTS ) return 0;
+	if (ipv6_find_hdr(skb, &ptr, NEXTHDR_HOP, NULL) < 0)
 #else
-       if ( temp != MASK_DSTOPTS ) return 0;
+	if (ipv6_find_hdr(skb, &ptr, NEXTHDR_DEST, NULL) < 0)
 #endif
+		return 0;
 
-       if (len < (int)sizeof(struct ipv6_opt_hdr)){
-	       *hotdrop = 1;
-       		return 0;
-       }
-
-       if (len < hdrlen){
-	       /* Packet smaller than it's length field */
-       		return 0;
-       }
+	oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh);
+	if (oh == NULL) {
+		*hotdrop = 1;
+		return 0;
+	}
 
-       optsh=(void *)(skb->data)+ptr;
+	hdrlen = ipv6_optlen(oh);
+	if (skb->len - ptr < hdrlen) {
+		/* Packet smaller than it's length field */
+		return 0;
+	}
 
-       DEBUGP("IPv6 OPTS LEN %u %u ", hdrlen, optsh->hdrlen);
+	DEBUGP("IPv6 OPTS LEN %u %u ", hdrlen, oh->hdrlen);
 
-       DEBUGP("len %02X %04X %02X ",
-       		optinfo->hdrlen, hdrlen,
-       		(!(optinfo->flags & IP6T_OPTS_LEN) ||
-                           ((optinfo->hdrlen == hdrlen) ^
-                           !!(optinfo->invflags & IP6T_OPTS_INV_LEN))));
+	DEBUGP("len %02X %04X %02X ",
+	       optinfo->hdrlen, hdrlen,
+	       (!(optinfo->flags & IP6T_OPTS_LEN) ||
+		((optinfo->hdrlen == hdrlen) ^
+		 !!(optinfo->invflags & IP6T_OPTS_INV_LEN))));
 
-       ret = (optsh != NULL)
-       		&&
-	      	(!(optinfo->flags & IP6T_OPTS_LEN) ||
-                           ((optinfo->hdrlen == hdrlen) ^
-                           !!(optinfo->invflags & IP6T_OPTS_INV_LEN)));
+	ret = (oh != NULL) &&
+	      (!(optinfo->flags & IP6T_OPTS_LEN) ||
+	       ((optinfo->hdrlen == hdrlen) ^
+		!!(optinfo->invflags & IP6T_OPTS_INV_LEN)));
 
-       temp = len = 0;
-       ptr += 2;
-       hdrlen -= 2;
-       if ( !(optinfo->flags & IP6T_OPTS_OPTS) ){
-	       return ret;
+	ptr += 2;
+	hdrlen -= 2;
+	if (!(optinfo->flags & IP6T_OPTS_OPTS)) {
+		return ret;
 	} else if (optinfo->flags & IP6T_OPTS_NSTRICT) {
 		DEBUGP("Not strict - not implemented");
 	} else {
 		DEBUGP("Strict ");
-		DEBUGP("#%d ",optinfo->optsnr);
-		for(temp=0; temp<optinfo->optsnr; temp++){
-			optdesc = (void *)(skb->data)+ptr;
+		DEBUGP("#%d ", optinfo->optsnr);
+		for (temp = 0; temp < optinfo->optsnr; temp++) {
+			/* type field exists ? */
+			if (hdrlen < 1)
+				break;
+			tp = skb_header_pointer(skb, ptr, sizeof(_opttype),
+						&_opttype);
+			if (tp == NULL)
+				break;
+
 			/* Type check */
-			if ( (unsigned char)*optdesc != 
-				(optinfo->opts[temp] & 0xFF00)>>8 ){
+			if (*tp != (optinfo->opts[temp] & 0xFF00) >> 8) {
 				DEBUGP("Tbad %02X %02X\n",
-						(unsigned char)*optdesc,
-						(optinfo->opts[temp] &
-						 0xFF00)>>8);
+				       *tp,
+				       (optinfo->opts[temp] & 0xFF00) >> 8);
 				return 0;
 			} else {
 				DEBUGP("Tok ");
 			}
 			/* Length check */
-			if (((optinfo->opts[temp] & 0x00FF) != 0xFF) &&
-				(unsigned char)*optdesc != 0){
-				if ( ntohs((u16)*optdesc) != 
-						optinfo->opts[temp] ){
-					DEBUGP("Lbad %02X %04X %04X\n",
-							(unsigned char)*optdesc,
-							ntohs((u16)*optdesc),
-							optinfo->opts[temp]);
+			if (*tp) {
+				u16 spec_len;
+
+				/* length field exists ? */
+				if (hdrlen < 2)
+					break;
+				lp = skb_header_pointer(skb, ptr + 1,
+							sizeof(_optlen),
+							&_optlen);
+				if (lp == NULL)
+					break;
+				spec_len = optinfo->opts[temp] & 0x00FF;
+
+				if (spec_len != 0x00FF && spec_len != *lp) {
+					DEBUGP("Lbad %02X %04X\n", *lp,
+					       spec_len);
 					return 0;
-				} else {
-					DEBUGP("Lok ");
 				}
-			}
-			/* Step to the next */
-			if ((unsigned char)*optdesc == 0){
-				DEBUGP("PAD0 \n");
-				ptr++;
-				hdrlen--;
+				DEBUGP("Lok ");
+				optlen = *lp + 2;
 			} else {
-				ptr += LOW(ntohs(*optdesc));
-				hdrlen -= LOW(ntohs(*optdesc));
-				DEBUGP("len%04X \n", 
-					LOW(ntohs(*optdesc)));
+				DEBUGP("Pad1\n");
+				optlen = 1;
 			}
-			if (ptr > skb->len || ( !hdrlen && 
-				(temp != optinfo->optsnr - 1))) {
+
+			/* Step to the next */
+			DEBUGP("len%04X \n", optlen);
+
+			if ((ptr > skb->len - optlen || hdrlen < optlen) &&
+			    (temp < optinfo->optsnr - 1)) {
 				DEBUGP("new pointer is too large! \n");
 				break;
 			}
+			ptr += optlen;
+			hdrlen -= optlen;
 		}
 		if (temp == optinfo->optsnr)
 			return ret;
-		else return 0;
+		else
+			return 0;
 	}
 
 	return 0;
@@ -241,25 +179,19 @@ match(const struct sk_buff *skb,
 /* Called when user tries to insert an entry of this type. */
 static int
 checkentry(const char *tablename,
-          const struct ip6t_ip6 *ip,
-          void *matchinfo,
-          unsigned int matchinfosize,
-          unsigned int hook_mask)
+	   const void *entry,
+	   const struct xt_match *match,
+	   void *matchinfo,
+	   unsigned int matchinfosize,
+	   unsigned int hook_mask)
 {
-       const struct ip6t_opts *optsinfo = matchinfo;
-
-       if (matchinfosize != IP6T_ALIGN(sizeof(struct ip6t_opts))) {
-              DEBUGP("ip6t_opts: matchsize %u != %u\n",
-                      matchinfosize, IP6T_ALIGN(sizeof(struct ip6t_opts)));
-              return 0;
-       }
-       if (optsinfo->invflags & ~IP6T_OPTS_INV_MASK) {
-              DEBUGP("ip6t_opts: unknown flags %X\n",
-                      optsinfo->invflags);
-              return 0;
-       }
+	const struct ip6t_opts *optsinfo = matchinfo;
 
-       return 1;
+	if (optsinfo->invflags & ~IP6T_OPTS_INV_MASK) {
+		DEBUGP("ip6t_opts: unknown flags %X\n", optsinfo->invflags);
+		return 0;
+	}
+	return 1;
 }
 
 static struct ip6t_match opts_match = {
@@ -268,20 +200,21 @@ static struct ip6t_match opts_match = {
 #else
 	.name		= "dst",
 #endif
-	.match		= &match,
-	.checkentry	= &checkentry,
+	.match		= match,
+	.matchsize	= sizeof(struct ip6t_opts),
+	.checkentry	= checkentry,
 	.me		= THIS_MODULE,
 };
 
-static int __init init(void)
+static int __init ip6t_hbh_init(void)
 {
-       return ip6t_register_match(&opts_match);
+	return ip6t_register_match(&opts_match);
 }
 
-static void __exit cleanup(void)
+static void __exit ip6t_hbh_fini(void)
 {
-       ip6t_unregister_match(&opts_match);
+	ip6t_unregister_match(&opts_match);
 }
 
-module_init(init);
-module_exit(cleanup);
+module_init(ip6t_hbh_init);
+module_exit(ip6t_hbh_fini);