X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=net%2Fipv6%2Fnetfilter%2Fip6t_frag.c;h=06768c84bd3110993f570dbf54809fa27581b921;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=d6eabaaf0f2fc89bf130795248ddd96e3114bb89;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git diff --git a/net/ipv6/netfilter/ip6t_frag.c b/net/ipv6/netfilter/ip6t_frag.c index d6eabaaf0..06768c84b 100644 --- a/net/ipv6/netfilter/ip6t_frag.c +++ b/net/ipv6/netfilter/ip6t_frag.c @@ -14,8 +14,6 @@ #include #include -#include - #include #include @@ -29,222 +27,127 @@ MODULE_AUTHOR("Andras Kis-Szabo "); #define DEBUGP(format, args...) #endif -#if 0 -#if BYTE_ORDER == BIG_ENDIAN -#define IP6F_OFF_MASK 0xfff8 /* mask out offset from _offlg */ -#define IP6F_RESERVED_MASK 0x0006 /* reserved bits in ip6f_offlg */ -#define IP6F_MORE_FRAG 0x0001 /* more-fragments flag */ -#else /* BYTE_ORDER == LITTLE_ENDIAN */ -#define IP6F_OFF_MASK 0xf8ff /* mask out offset from _offlg */ -#define IP6F_RESERVED_MASK 0x0600 /* reserved bits in ip6f_offlg */ -#define IP6F_MORE_FRAG 0x0100 /* more-fragments flag */ -#endif -#endif - -#define IP6F_OFF_MASK 0xf8ff /* mask out offset from _offlg */ -#define IP6F_RESERVED_MASK 0x0600 /* reserved bits in ip6f_offlg */ -#define IP6F_MORE_FRAG 0x0100 /* more-fragments flag */ - -struct fraghdr { - __u8 nexthdr; - __u8 hdrlen; - __u16 info; - __u32 id; -}; - /* Returns 1 if the id is matched by the range, 0 otherwise */ static inline int id_match(u_int32_t min, u_int32_t max, u_int32_t id, int invert) { - int r=0; - DEBUGP("frag id_match:%c 0x%x <= 0x%x <= 0x%x",invert? '!':' ', - min,id,max); - r=(id >= min && id <= max) ^ invert; - DEBUGP(" result %s\n",r? "PASS" : "FAILED"); - return r; + int r = 0; + DEBUGP("frag id_match:%c 0x%x <= 0x%x <= 0x%x", invert ? '!' : ' ', + min, id, max); + r = (id >= min && id <= max) ^ invert; + DEBUGP(" result %s\n", r ? "PASS" : "FAILED"); + return r; } 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 fraghdr *frag = NULL; - 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; - - 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; - } - - hdr=(struct ipv6_opt_hdr *)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); - - /* 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 = hdr->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 < (int)sizeof(struct fraghdr)){ - *hotdrop = 1; - return 0; - } - - frag = (struct fraghdr *) (skb->data + ptr); - - DEBUGP("IPv6 FRAG LEN %u %u ", hdrlen, frag->hdrlen); - DEBUGP("INFO %04X ", frag->info); - DEBUGP("OFFSET %04X ", frag->info & IP6F_OFF_MASK); - DEBUGP("RES %04X ", frag->info & IP6F_RESERVED_MASK); - DEBUGP("MF %04X ", frag->info & IP6F_MORE_FRAG); - DEBUGP("ID %u %08X\n", ntohl(frag->id), ntohl(frag->id)); - - DEBUGP("IPv6 FRAG id %02X ", - (id_match(fraginfo->ids[0], fraginfo->ids[1], - ntohl(frag->id), - !!(fraginfo->invflags & IP6T_FRAG_INV_IDS)))); - DEBUGP("len %02X %04X %02X ", - fraginfo->hdrlen, hdrlen, - (!fraginfo->hdrlen || - (fraginfo->hdrlen == hdrlen) ^ - !!(fraginfo->invflags & IP6T_FRAG_INV_LEN))); - DEBUGP("res %02X %02X %02X ", - (fraginfo->flags & IP6T_FRAG_RES), frag->info & IP6F_RESERVED_MASK, - !((fraginfo->flags & IP6T_FRAG_RES) && (frag->info & IP6F_RESERVED_MASK))); - DEBUGP("first %02X %02X %02X ", - (fraginfo->flags & IP6T_FRAG_FST), frag->info & IP6F_OFF_MASK, - !((fraginfo->flags & IP6T_FRAG_FST) && (frag->info & IP6F_OFF_MASK))); - DEBUGP("mf %02X %02X %02X ", - (fraginfo->flags & IP6T_FRAG_MF), frag->info & IP6F_MORE_FRAG, - !((fraginfo->flags & IP6T_FRAG_MF) && !((frag->info & IP6F_MORE_FRAG)))); - DEBUGP("last %02X %02X %02X\n", - (fraginfo->flags & IP6T_FRAG_NMF), frag->info & IP6F_MORE_FRAG, - !((fraginfo->flags & IP6T_FRAG_NMF) && (frag->info & IP6F_MORE_FRAG))); - - return (frag != NULL) - && - (id_match(fraginfo->ids[0], fraginfo->ids[1], - ntohl(frag->id), - !!(fraginfo->invflags & IP6T_FRAG_INV_IDS))) - && - (!fraginfo->hdrlen || - (fraginfo->hdrlen == hdrlen) ^ - !!(fraginfo->invflags & IP6T_FRAG_INV_LEN)) - && - !((fraginfo->flags & IP6T_FRAG_RES) && (frag->info & IP6F_RESERVED_MASK)) - && - !((fraginfo->flags & IP6T_FRAG_FST) && (frag->info & IP6F_OFF_MASK)) - && - !((fraginfo->flags & IP6T_FRAG_MF) && !((frag->info & IP6F_MORE_FRAG))) - && - !((fraginfo->flags & IP6T_FRAG_NMF) && (frag->info & IP6F_MORE_FRAG)); + struct frag_hdr _frag, *fh; + const struct ip6t_frag *fraginfo = matchinfo; + unsigned int ptr; + + if (ipv6_find_hdr(skb, &ptr, NEXTHDR_FRAGMENT, NULL) < 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); + DEBUGP("RES %02X %04X", fh->reserved, ntohs(fh->frag_off) & 0x6); + DEBUGP("MF %04X ", fh->frag_off & htons(IP6_MF)); + DEBUGP("ID %u %08X\n", ntohl(fh->identification), + ntohl(fh->identification)); + + DEBUGP("IPv6 FRAG id %02X ", + (id_match(fraginfo->ids[0], fraginfo->ids[1], + ntohl(fh->identification), + !!(fraginfo->invflags & IP6T_FRAG_INV_IDS)))); + DEBUGP("res %02X %02X%04X %02X ", + (fraginfo->flags & IP6T_FRAG_RES), fh->reserved, + ntohs(fh->frag_off) & 0x6, + !((fraginfo->flags & IP6T_FRAG_RES) + && (fh->reserved || (ntohs(fh->frag_off) & 0x06)))); + DEBUGP("first %02X %02X %02X ", + (fraginfo->flags & IP6T_FRAG_FST), + ntohs(fh->frag_off) & ~0x7, + !((fraginfo->flags & IP6T_FRAG_FST) + && (ntohs(fh->frag_off) & ~0x7))); + DEBUGP("mf %02X %02X %02X ", + (fraginfo->flags & IP6T_FRAG_MF), + ntohs(fh->frag_off) & IP6_MF, + !((fraginfo->flags & IP6T_FRAG_MF) + && !((ntohs(fh->frag_off) & IP6_MF)))); + DEBUGP("last %02X %02X %02X\n", + (fraginfo->flags & IP6T_FRAG_NMF), + ntohs(fh->frag_off) & IP6_MF, + !((fraginfo->flags & IP6T_FRAG_NMF) + && (ntohs(fh->frag_off) & IP6_MF))); + + return (fh != NULL) + && + (id_match(fraginfo->ids[0], fraginfo->ids[1], + ntohl(fh->identification), + !!(fraginfo->invflags & IP6T_FRAG_INV_IDS))) + && + !((fraginfo->flags & IP6T_FRAG_RES) + && (fh->reserved || (ntohs(fh->frag_off) & 0x6))) + && + !((fraginfo->flags & IP6T_FRAG_FST) + && (ntohs(fh->frag_off) & ~0x7)) + && + !((fraginfo->flags & IP6T_FRAG_MF) + && !(ntohs(fh->frag_off) & IP6_MF)) + && + !((fraginfo->flags & IP6T_FRAG_NMF) + && (ntohs(fh->frag_off) & IP6_MF)); } /* 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 *ip, + const struct xt_match *match, + void *matchinfo, + unsigned int matchinfosize, + unsigned int hook_mask) { - const struct ip6t_frag *fraginfo = matchinfo; - - if (matchinfosize != IP6T_ALIGN(sizeof(struct ip6t_frag))) { - DEBUGP("ip6t_frag: matchsize %u != %u\n", - matchinfosize, IP6T_ALIGN(sizeof(struct ip6t_frag))); - return 0; - } - if (fraginfo->invflags & ~IP6T_FRAG_INV_MASK) { - DEBUGP("ip6t_frag: unknown flags %X\n", - fraginfo->invflags); - return 0; - } - - return 1; + const struct ip6t_frag *fraginfo = matchinfo; + + if (fraginfo->invflags & ~IP6T_FRAG_INV_MASK) { + DEBUGP("ip6t_frag: unknown flags %X\n", fraginfo->invflags); + return 0; + } + return 1; } static struct ip6t_match frag_match = { .name = "frag", - .match = &match, - .checkentry = &checkentry, + .match = match, + .matchsize = sizeof(struct ip6t_frag), + .checkentry = checkentry, .me = THIS_MODULE, }; -static int __init init(void) +static int __init ip6t_frag_init(void) { - return ip6t_register_match(&frag_match); + return ip6t_register_match(&frag_match); } -static void __exit cleanup(void) +static void __exit ip6t_frag_fini(void) { - ip6t_unregister_match(&frag_match); + ip6t_unregister_match(&frag_match); } -module_init(init); -module_exit(cleanup); +module_init(ip6t_frag_init); +module_exit(ip6t_frag_fini);