/* 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))
#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);
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);
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);
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;
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 ",
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)
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);
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;
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 ",
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);