From e674d0f38de6109b59dbe30fba8b296a03229b8e Mon Sep 17 00:00:00 2001 From: Yasuyuki Kozakai Date: Mon, 19 Sep 2005 15:34:40 -0700 Subject: [PATCH] [NETFILTER] ip6tables: remove duplicate code Some IPv6 matches have very similar loops to find IPv6 extension header and we can unify them. This patch introduces ipv6_find_hdr() to do it. I just checked that it can find the target headers in the packet which has dst,hbh,rt,frag,ah,esp headers. Signed-off-by: Yasuyuki Kozakai Signed-off-by: Harald Welte Signed-off-by: David S. Miller --- include/linux/netfilter_ipv6/ip6_tables.h | 3 + net/ipv6/netfilter/ip6_tables.c | 52 +++++++++++++ net/ipv6/netfilter/ip6t_ah.c | 81 ++------------------ net/ipv6/netfilter/ip6t_dst.c | 88 ++-------------------- net/ipv6/netfilter/ip6t_esp.c | 73 +----------------- net/ipv6/netfilter/ip6t_frag.c | 90 +++-------------------- net/ipv6/netfilter/ip6t_hbh.c | 88 ++-------------------- net/ipv6/netfilter/ip6t_rt.c | 83 ++------------------- 8 files changed, 94 insertions(+), 464 deletions(-) diff --git a/include/linux/netfilter_ipv6/ip6_tables.h b/include/linux/netfilter_ipv6/ip6_tables.h index 58c72a52dc6..59f70b34e02 100644 --- a/include/linux/netfilter_ipv6/ip6_tables.h +++ b/include/linux/netfilter_ipv6/ip6_tables.h @@ -455,6 +455,9 @@ extern unsigned int ip6t_do_table(struct sk_buff **pskb, /* Check for an extension */ extern int ip6t_ext_hdr(u8 nexthdr); +/* find specified header and get offset to it */ +extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, + u8 target); #define IP6T_ALIGN(s) (((s) + (__alignof__(struct ip6t_entry)-1)) & ~(__alignof__(struct ip6t_entry)-1)) diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 1cb8adb2787..2da514b16d9 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -1955,6 +1955,57 @@ static void __exit fini(void) #endif } +/* + * find specified header up to transport protocol header. + * If found target header, the offset to the header is set to *offset + * and return 0. otherwise, return -1. + * + * Notes: - non-1st Fragment Header isn't skipped. + * - ESP header isn't skipped. + * - The target header may be trancated. + */ +int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, u8 target) +{ + unsigned int start = (u8*)(skb->nh.ipv6h + 1) - skb->data; + u8 nexthdr = skb->nh.ipv6h->nexthdr; + unsigned int len = skb->len - start; + + while (nexthdr != target) { + struct ipv6_opt_hdr _hdr, *hp; + unsigned int hdrlen; + + if ((!ipv6_ext_hdr(nexthdr)) || nexthdr == NEXTHDR_NONE) + return -1; + hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr); + if (hp == NULL) + return -1; + if (nexthdr == NEXTHDR_FRAGMENT) { + unsigned short _frag_off, *fp; + fp = skb_header_pointer(skb, + start+offsetof(struct frag_hdr, + frag_off), + sizeof(_frag_off), + &_frag_off); + if (fp == NULL) + return -1; + + if (ntohs(*fp) & ~0x7) + return -1; + hdrlen = 8; + } else if (nexthdr == NEXTHDR_AUTH) + hdrlen = (hp->hdrlen + 2) << 2; + else + hdrlen = ipv6_optlen(hp); + + nexthdr = hp->nexthdr; + len -= hdrlen; + start += hdrlen; + } + + *offset = start; + return 0; +} + EXPORT_SYMBOL(ip6t_register_table); EXPORT_SYMBOL(ip6t_unregister_table); EXPORT_SYMBOL(ip6t_do_table); @@ -1963,6 +2014,7 @@ EXPORT_SYMBOL(ip6t_unregister_match); EXPORT_SYMBOL(ip6t_register_target); EXPORT_SYMBOL(ip6t_unregister_target); EXPORT_SYMBOL(ip6t_ext_hdr); +EXPORT_SYMBOL(ipv6_find_hdr); module_init(init); module_exit(fini); diff --git a/net/ipv6/netfilter/ip6t_ah.c b/net/ipv6/netfilter/ip6t_ah.c index d5b94f142bb..dde37793d20 100644 --- a/net/ipv6/netfilter/ip6t_ah.c +++ b/net/ipv6/netfilter/ip6t_ah.c @@ -48,92 +48,21 @@ match(const struct sk_buff *skb, unsigned int protoff, int *hotdrop) { - struct ip_auth_hdr *ah = NULL, _ah; + struct ip_auth_hdr *ah, _ah; const struct ip6t_ah *ahinfo = matchinfo; - unsigned int temp; - int len; - u8 nexthdr; unsigned int ptr; unsigned int hdrlen = 0; - /*DEBUGP("IPv6 AH entered\n");*/ - /* if (opt->auth == 0) return 0; - * It does not filled on output */ - - /* 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, *hp; - - DEBUGP("ipv6_ah header iteration \n"); - - /* Is there enough space for the next ext header? */ - if (len < sizeof(struct ipv6_opt_hdr)) - return 0; - /* No more exthdr -> evaluate */ - if (nexthdr == NEXTHDR_NONE) - break; - /* ESP -> evaluate */ - if (nexthdr == NEXTHDR_ESP) - break; - - hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr); - BUG_ON(hp == NULL); - - /* Calculate the header length */ - if (nexthdr == NEXTHDR_FRAGMENT) - hdrlen = 8; - else if (nexthdr == NEXTHDR_AUTH) - hdrlen = (hp->hdrlen+2)<<2; - else - hdrlen = ipv6_optlen(hp); - - /* AH -> evaluate */ - if (nexthdr == NEXTHDR_AUTH) { - temp |= MASK_AH; - 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_ah match: unknown nextheader %u\n",nexthdr); - return 0; - } - - nexthdr = hp->nexthdr; - len -= hdrlen; - ptr += hdrlen; - if (ptr > skb->len) { - DEBUGP("ipv6_ah: new pointer too large! \n"); - break; - } - } - - /* AH header not found */ - if (temp != MASK_AH) + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_AUTH) < 0) return 0; - if (len < sizeof(struct ip_auth_hdr)){ + ah = skb_header_pointer(skb, ptr, sizeof(_ah), &_ah); + if (ah == NULL) { *hotdrop = 1; return 0; } - ah = skb_header_pointer(skb, ptr, sizeof(_ah), &_ah); - BUG_ON(ah == NULL); + hdrlen = (ah->hdrlen + 2) << 2; DEBUGP("IPv6 AH LEN %u %u ", hdrlen, ah->hdrlen); DEBUGP("RES %04X ", ah->reserved); diff --git a/net/ipv6/netfilter/ip6t_dst.c b/net/ipv6/netfilter/ip6t_dst.c index 540925e4a7a..c450a635e54 100644 --- a/net/ipv6/netfilter/ip6t_dst.c +++ b/net/ipv6/netfilter/ip6t_dst.c @@ -63,8 +63,6 @@ match(const struct sk_buff *skb, struct ipv6_opt_hdr _optsh, *oh; 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; @@ -72,97 +70,25 @@ match(const struct sk_buff *skb, u8 _optlen, *lp = NULL; unsigned int optlen; - /* 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, *hp; - - 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; - } - - hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr); - BUG_ON(hp == NULL); - - /* Calculate the header length */ - if (nexthdr == NEXTHDR_FRAGMENT) { - hdrlen = 8; - } else if (nexthdr == NEXTHDR_AUTH) - hdrlen = (hp->hdrlen+2)<<2; - else - hdrlen = ipv6_optlen(hp); - - /* OPTS -> evaluate */ #if HOPBYHOP - if (nexthdr == NEXTHDR_HOP) { - temp |= MASK_HOPOPTS; + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_HOP) < 0) #else - if (nexthdr == NEXTHDR_DEST) { - temp |= MASK_DSTOPTS; + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_DEST) < 0) #endif - break; - } - + return 0; - /* 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 = hp->nexthdr; - len -= hdrlen; - ptr += hdrlen; - if ( ptr > skb->len ) { - DEBUGP("ipv6_opts: new pointer is too large! \n"); - break; - } - } - - /* OPTIONS header not found */ -#if HOPBYHOP - if ( temp != MASK_HOPOPTS ) return 0; -#else - if ( temp != MASK_DSTOPTS ) return 0; -#endif - - if (len < (int)sizeof(struct ipv6_opt_hdr)){ + oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh); + if (oh == NULL){ *hotdrop = 1; return 0; } - if (len < hdrlen){ + hdrlen = ipv6_optlen(oh); + if (skb->len - ptr < hdrlen){ /* Packet smaller than it's length field */ return 0; } - oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh); - BUG_ON(oh == NULL); - DEBUGP("IPv6 OPTS LEN %u %u ", hdrlen, oh->hdrlen); DEBUGP("len %02X %04X %02X ", diff --git a/net/ipv6/netfilter/ip6t_esp.c b/net/ipv6/netfilter/ip6t_esp.c index e39dd236fd8..24bc0cde43a 100644 --- a/net/ipv6/netfilter/ip6t_esp.c +++ b/net/ipv6/netfilter/ip6t_esp.c @@ -48,87 +48,22 @@ match(const struct sk_buff *skb, unsigned int protoff, int *hotdrop) { - struct ip_esp_hdr _esp, *eh = NULL; + struct ip_esp_hdr _esp, *eh; const struct ip6t_esp *espinfo = matchinfo; - unsigned int temp; - int len; - u8 nexthdr; unsigned int ptr; /* Make sure this isn't an evil packet */ /*DEBUGP("ipv6_esp entered \n");*/ - /* 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, *hp; - int hdrlen; - - DEBUGP("ipv6_esp header iteration \n"); - - /* Is there enough space for the next ext header? */ - if (len < sizeof(struct ipv6_opt_hdr)) - return 0; - /* No more exthdr -> evaluate */ - if (nexthdr == NEXTHDR_NONE) - break; - /* ESP -> evaluate */ - if (nexthdr == NEXTHDR_ESP) { - temp |= MASK_ESP; - break; - } - - hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr); - BUG_ON(hp == NULL); - - /* Calculate the header length */ - if (nexthdr == NEXTHDR_FRAGMENT) - hdrlen = 8; - else if (nexthdr == NEXTHDR_AUTH) - hdrlen = (hp->hdrlen+2)<<2; - else - hdrlen = ipv6_optlen(hp); - - /* set the flag */ - switch (nexthdr) { - case NEXTHDR_HOP: - case NEXTHDR_ROUTING: - case NEXTHDR_FRAGMENT: - case NEXTHDR_AUTH: - case NEXTHDR_DEST: - break; - default: - DEBUGP("ipv6_esp match: unknown nextheader %u\n",nexthdr); - return 0; - } - - nexthdr = hp->nexthdr; - len -= hdrlen; - ptr += hdrlen; - if (ptr > skb->len) { - DEBUGP("ipv6_esp: new pointer too large! \n"); - break; - } - } - - /* ESP header not found */ - if (temp != MASK_ESP) + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_ESP) < 0) return 0; - if (len < sizeof(struct ip_esp_hdr)) { + eh = skb_header_pointer(skb, ptr, sizeof(_esp), &_esp); + if (eh == NULL) { *hotdrop = 1; return 0; } - eh = skb_header_pointer(skb, ptr, sizeof(_esp), &_esp); - BUG_ON(eh == NULL); - DEBUGP("IPv6 ESP SPI %u %08X\n", ntohl(eh->spi), ntohl(eh->spi)); return (eh != NULL) diff --git a/net/ipv6/netfilter/ip6t_frag.c b/net/ipv6/netfilter/ip6t_frag.c index 4bfa30a9bc8..085d5f8eea2 100644 --- a/net/ipv6/netfilter/ip6t_frag.c +++ b/net/ipv6/netfilter/ip6t_frag.c @@ -48,90 +48,18 @@ match(const struct sk_buff *skb, unsigned int protoff, int *hotdrop) { - struct frag_hdr _frag, *fh = NULL; + struct frag_hdr _frag, *fh; const struct ip6t_frag *fraginfo = matchinfo; - unsigned int temp; - int len; - u8 nexthdr; unsigned int ptr; - unsigned int hdrlen = 0; - - /* 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, *hp; - - DEBUGP("ipv6_frag 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; - } - - hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr); - BUG_ON(hp == NULL); - - /* Calculate the header length */ - if (nexthdr == NEXTHDR_FRAGMENT) { - hdrlen = 8; - } else if (nexthdr == NEXTHDR_AUTH) - hdrlen = (hp->hdrlen+2)<<2; - else - hdrlen = ipv6_optlen(hp); - - /* FRAG -> evaluate */ - if (nexthdr == NEXTHDR_FRAGMENT) { - temp |= MASK_FRAGMENT; - 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_frag match: unknown nextheader %u\n",nexthdr); - return 0; - break; - } - - nexthdr = hp->nexthdr; - len -= hdrlen; - ptr += hdrlen; - if ( ptr > skb->len ) { - DEBUGP("ipv6_frag: new pointer too large! \n"); - break; - } - } - - /* FRAG header not found */ - if ( temp != MASK_FRAGMENT ) return 0; - - if (len < sizeof(struct frag_hdr)){ - *hotdrop = 1; - return 0; - } - fh = skb_header_pointer(skb, ptr, sizeof(_frag), &_frag); - BUG_ON(fh == NULL); + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_FRAGMENT) < 0) + return 0; + + fh = skb_header_pointer(skb, ptr, sizeof(_frag), &_frag); + if (fh == NULL){ + *hotdrop = 1; + return 0; + } DEBUGP("INFO %04X ", fh->frag_off); DEBUGP("OFFSET %04X ", ntohs(fh->frag_off) & ~0x7); diff --git a/net/ipv6/netfilter/ip6t_hbh.c b/net/ipv6/netfilter/ip6t_hbh.c index 27f3650d127..1d09485111d 100644 --- a/net/ipv6/netfilter/ip6t_hbh.c +++ b/net/ipv6/netfilter/ip6t_hbh.c @@ -63,8 +63,6 @@ match(const struct sk_buff *skb, struct ipv6_opt_hdr _optsh, *oh; 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; @@ -72,97 +70,25 @@ match(const struct sk_buff *skb, u8 _optlen, *lp = NULL; unsigned int optlen; - /* 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, *hp; - - 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; - } - - hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr); - BUG_ON(hp == NULL); - - /* Calculate the header length */ - if (nexthdr == NEXTHDR_FRAGMENT) { - hdrlen = 8; - } else if (nexthdr == NEXTHDR_AUTH) - hdrlen = (hp->hdrlen+2)<<2; - else - hdrlen = ipv6_optlen(hp); - - /* OPTS -> evaluate */ #if HOPBYHOP - if (nexthdr == NEXTHDR_HOP) { - temp |= MASK_HOPOPTS; + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_HOP) < 0) #else - if (nexthdr == NEXTHDR_DEST) { - temp |= MASK_DSTOPTS; + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_DEST) < 0) #endif - break; - } - + return 0; - /* 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 = hp->nexthdr; - len -= hdrlen; - ptr += hdrlen; - if ( ptr > skb->len ) { - DEBUGP("ipv6_opts: new pointer is too large! \n"); - break; - } - } - - /* OPTIONS header not found */ -#if HOPBYHOP - if ( temp != MASK_HOPOPTS ) return 0; -#else - if ( temp != MASK_DSTOPTS ) return 0; -#endif - - if (len < (int)sizeof(struct ipv6_opt_hdr)){ + oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh); + if (oh == NULL){ *hotdrop = 1; return 0; } - if (len < hdrlen){ + hdrlen = ipv6_optlen(oh); + if (skb->len - ptr < hdrlen){ /* Packet smaller than it's length field */ return 0; } - oh = skb_header_pointer(skb, ptr, sizeof(_optsh), &_optsh); - BUG_ON(oh == NULL); - DEBUGP("IPv6 OPTS LEN %u %u ", hdrlen, oh->hdrlen); DEBUGP("len %02X %04X %02X ", diff --git a/net/ipv6/netfilter/ip6t_rt.c b/net/ipv6/netfilter/ip6t_rt.c index 2bb670037df..beb2fd5cebb 100644 --- a/net/ipv6/netfilter/ip6t_rt.c +++ b/net/ipv6/netfilter/ip6t_rt.c @@ -50,98 +50,29 @@ match(const struct sk_buff *skb, unsigned int protoff, int *hotdrop) { - struct ipv6_rt_hdr _route, *rh = NULL; + struct ipv6_rt_hdr _route, *rh; const struct ip6t_rt *rtinfo = matchinfo; unsigned int temp; - unsigned int len; - u8 nexthdr; unsigned int ptr; unsigned int hdrlen = 0; unsigned int ret = 0; struct in6_addr *ap, _addr; - /* 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; + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_ROUTING) < 0) + return 0; - while (ip6t_ext_hdr(nexthdr)) { - struct ipv6_opt_hdr _hdr, *hp; - - DEBUGP("ipv6_rt 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; - } - - hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr); - BUG_ON(hp == NULL); - - /* Calculate the header length */ - if (nexthdr == NEXTHDR_FRAGMENT) { - hdrlen = 8; - } else if (nexthdr == NEXTHDR_AUTH) - hdrlen = (hp->hdrlen+2)<<2; - else - hdrlen = ipv6_optlen(hp); - - /* ROUTING -> evaluate */ - if (nexthdr == NEXTHDR_ROUTING) { - temp |= MASK_ROUTING; - 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_rt match: unknown nextheader %u\n",nexthdr); - return 0; - break; - } - - nexthdr = hp->nexthdr; - len -= hdrlen; - ptr += hdrlen; - if ( ptr > skb->len ) { - DEBUGP("ipv6_rt: new pointer is too large! \n"); - break; - } - } - - /* ROUTING header not found */ - if ( temp != MASK_ROUTING ) return 0; - - if (len < (int)sizeof(struct ipv6_rt_hdr)){ + rh = skb_header_pointer(skb, ptr, sizeof(_route), &_route); + if (rh == NULL){ *hotdrop = 1; return 0; } - if (len < hdrlen){ + hdrlen = ipv6_optlen(rh); + if (skb->len - ptr < hdrlen){ /* Pcket smaller than its length field */ return 0; } - rh = skb_header_pointer(skb, ptr, sizeof(_route), &_route); - BUG_ON(rh == NULL); - DEBUGP("IPv6 RT LEN %u %u ", hdrlen, rh->hdrlen); DEBUGP("TYPE %04X ", rh->type); DEBUGP("SGS_LEFT %u %02X\n", rh->segments_left, rh->segments_left); -- 2.41.1