[NETFILTER]: Backport fixes for ip6t_frag
Linux Kernel Mailing List <[email protected]>
| Newsgroups | gmane.linux.kernel.commits.2-4 |
|---|---|
| Message-ID | <[email protected]> |
ChangeSet 1.1542, 2004/12/21 17:38:52+01:00, [email protected] [NETFILTER]: Backport fixes for ip6t_frag This patch fixes following bugs in ip6t_frag.c: - Wrong cast the pointer to extension header. - replaced "struct fraghdr" with "struct frag_hdr". - header length of Fragment Header is statically 8 octets. Then the option "--frag-len" doesn't make sense. - There are endian issues where using frag->info. - Reserved fields are not 2 bit but 8bit + 2 bit. (see RFC2460) Signed-off-by: Yasuyuki KOZAKAI <[email protected]> Signed-off-by: Patrick McHardy <[email protected]> ip6t_frag.c | 96 +++++++++++++++++++++++------------------------------------- 1 files changed, 38 insertions(+), 58 deletions(-) diff -Nru a/net/ipv6/netfilter/ip6t_frag.c b/net/ipv6/netfilter/ip6t_frag.c --- a/net/ipv6/netfilter/ip6t_frag.c 2005-01-15 07:04:35 -08:00 +++ b/net/ipv6/netfilter/ip6t_frag.c 2005-01-15 07:04:35 -08:00 @@ -6,8 +6,6 @@ #include <net/checksum.h> #include <net/ipv6.h> -#include <asm/byteorder.h> - #include <linux/netfilter_ipv6/ip6_tables.h> #include <linux/netfilter_ipv6/ip6t_frag.h> @@ -22,28 +20,7 @@ #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; -}; +#define IP6_MF 0x0001 /* Returns 1 if the id is matched by the range, 0 otherwise */ static inline int @@ -67,7 +44,7 @@ u_int16_t datalen, int *hotdrop) { - struct fraghdr *frag = NULL; + struct frag_hdr *frag = NULL; const struct ip6t_frag *fraginfo = matchinfo; unsigned int temp; int len; @@ -100,7 +77,7 @@ break; } - hdr=(struct ipv6_opt_hdr *)skb->data+ptr; + hdr=(struct ipv6_opt_hdr *)(skb->data+ptr); /* Calculate the header length */ if (nexthdr == NEXTHDR_FRAGMENT) { @@ -143,59 +120,62 @@ /* FRAG header not found */ if ( temp != MASK_FRAGMENT ) return 0; - if (len < (int)sizeof(struct fraghdr)){ + if (len < sizeof(struct frag_hdr)){ *hotdrop = 1; return 0; } - frag = (struct fraghdr *) (skb->data + ptr); + frag = (struct frag_hdr *) (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("INFO %04X ", frag->frag_off); + DEBUGP("OFFSET %04X ", ntohs(frag->frag_off) & ~0x7); + DEBUGP("RES %02X %04X", frag->reserved, ntohs(frag->frag_off) & 0x6); + DEBUGP("MF %04X ", frag->frag_off & htons(IP6_MF)); + DEBUGP("ID %u %08X\n", ntohl(frag->identification), + ntohl(frag->identification)); DEBUGP("IPv6 FRAG id %02X ", (id_match(fraginfo->ids[0], fraginfo->ids[1], - ntohl(frag->id), + ntohl(frag->identification), !!(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("res %02X %02X%04X %02X ", + (fraginfo->flags & IP6T_FRAG_RES), frag->reserved, + ntohs(frag->frag_off) & 0x6, + !((fraginfo->flags & IP6T_FRAG_RES) + && (frag->reserved || (ntohs(frag->frag_off) & 0x6)))); 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))); + (fraginfo->flags & IP6T_FRAG_FST), + ntohs(frag->frag_off) & ~0x7, + !((fraginfo->flags & IP6T_FRAG_FST) + && (ntohs(frag->frag_off) & ~0x7))); 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)))); + (fraginfo->flags & IP6T_FRAG_MF), + ntohs(frag->frag_off) & IP6_MF, + !((fraginfo->flags & IP6T_FRAG_MF) + && !((ntohs(frag->frag_off) & IP6_MF)))); 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))); + (fraginfo->flags & IP6T_FRAG_NMF), + ntohs(frag->frag_off) & IP6_MF, + !((fraginfo->flags & IP6T_FRAG_NMF) + && (ntohs(frag->frag_off) & IP6_MF))); return (frag != NULL) && (id_match(fraginfo->ids[0], fraginfo->ids[1], - ntohl(frag->id), + ntohl(frag->identification), !!(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_RES) + && (frag->reserved || (ntohs(frag->frag_off) & 0x6))) && - !((fraginfo->flags & IP6T_FRAG_FST) && (frag->info & IP6F_OFF_MASK)) + !((fraginfo->flags & IP6T_FRAG_FST) + && (ntohs(frag->frag_off) & ~0x7)) && - !((fraginfo->flags & IP6T_FRAG_MF) && !((frag->info & IP6F_MORE_FRAG))) + !((fraginfo->flags & IP6T_FRAG_MF) + && !(ntohs(frag->frag_off) & IP6_MF)) && - !((fraginfo->flags & IP6T_FRAG_NMF) && (frag->info & IP6F_MORE_FRAG)); + !((fraginfo->flags & IP6T_FRAG_NMF) + && (ntohs(frag->frag_off) & IP6_MF)); } /* Called when user tries to insert an entry of this type. */