| /* |
| * Extension Header handling for IPv6 |
| * Linux INET6 implementation |
| * |
| * Authors: |
| * Pedro Roque <roque@di.fc.ul.pt> |
| * Andi Kleen <ak@muc.de> |
| * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> |
| * |
| * $Id: exthdrs.c,v 1.13 2001/06/19 15:58:56 davem Exp $ |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| |
| /* Changes: |
| * yoshfuji : ensure not to overrun while parsing |
| * tlv options. |
| * Mitsuru KANDA @USAGI and: Remove ipv6_parse_exthdrs(). |
| * YOSHIFUJI Hideaki @USAGI Register inbound extension header |
| * handlers as inet6_protocol{}. |
| */ |
| |
| #include <linux/errno.h> |
| #include <linux/types.h> |
| #include <linux/socket.h> |
| #include <linux/sockios.h> |
| #include <linux/sched.h> |
| #include <linux/net.h> |
| #include <linux/netdevice.h> |
| #include <linux/in6.h> |
| #include <linux/icmpv6.h> |
| |
| #include <net/sock.h> |
| #include <net/snmp.h> |
| |
| #include <net/ipv6.h> |
| #include <net/protocol.h> |
| #include <net/transp_v6.h> |
| #include <net/rawv6.h> |
| #include <net/ndisc.h> |
| #include <net/ip6_route.h> |
| #include <net/addrconf.h> |
| #ifdef CONFIG_IPV6_MIP6 |
| #include <net/xfrm.h> |
| #endif |
| |
| #include <asm/uaccess.h> |
| |
| int ipv6_find_tlv(struct sk_buff *skb, int offset, int type) |
| { |
| int packet_len = skb->tail - skb->nh.raw; |
| struct ipv6_opt_hdr *hdr; |
| int len; |
| |
| if (offset + 2 > packet_len) |
| goto bad; |
| hdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset); |
| len = ((hdr->hdrlen + 1) << 3); |
| |
| if (offset + len > packet_len) |
| goto bad; |
| |
| offset += 2; |
| len -= 2; |
| |
| while (len > 0) { |
| int opttype = skb->nh.raw[offset]; |
| int optlen; |
| |
| if (opttype == type) |
| return offset; |
| |
| switch (opttype) { |
| case IPV6_TLV_PAD0: |
| optlen = 1; |
| break; |
| default: |
| optlen = skb->nh.raw[offset + 1] + 2; |
| if (optlen > len) |
| goto bad; |
| break; |
| } |
| offset += optlen; |
| len -= optlen; |
| } |
| /* not_found */ |
| bad: |
| return -1; |
| } |
| |
| /* |
| * Parsing tlv encoded headers. |
| * |
| * Parsing function "func" returns 1, if parsing succeed |
| * and 0, if it failed. |
| * It MUST NOT touch skb->h. |
| */ |
| |
| struct tlvtype_proc { |
| int type; |
| int (*func)(struct sk_buff **skbp, int offset); |
| }; |
| |
| /********************* |
| Generic functions |
| *********************/ |
| |
| /* An unknown option is detected, decide what to do */ |
| |
| static int ip6_tlvopt_unknown(struct sk_buff **skbp, int optoff) |
| { |
| struct sk_buff *skb = *skbp; |
| |
| switch ((skb->nh.raw[optoff] & 0xC0) >> 6) { |
| case 0: /* ignore */ |
| return 1; |
| |
| case 1: /* drop packet */ |
| break; |
| |
| case 3: /* Send ICMP if not a multicast address and drop packet */ |
| /* Actually, it is redundant check. icmp_send |
| will recheck in any case. |
| */ |
| if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr)) |
| break; |
| case 2: /* send ICMP PARM PROB regardless and drop packet */ |
| icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff); |
| return 0; |
| }; |
| |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| /* Parse tlv encoded option header (hop-by-hop or destination) */ |
| |
| static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff **skbp) |
| { |
| struct sk_buff *skb = *skbp; |
| struct tlvtype_proc *curr; |
| int off = skb->h.raw - skb->nh.raw; |
| int len = ((skb->h.raw[1]+1)<<3); |
| |
| if ((skb->h.raw + len) - skb->data > skb_headlen(skb)) |
| goto bad; |
| |
| off += 2; |
| len -= 2; |
| |
| while (len > 0) { |
| int optlen = skb->nh.raw[off+1]+2; |
| |
| switch (skb->nh.raw[off]) { |
| case IPV6_TLV_PAD0: |
| optlen = 1; |
| break; |
| |
| case IPV6_TLV_PADN: |
| break; |
| |
| default: /* Other TLV code so scan list */ |
| if (optlen > len) |
| goto bad; |
| for (curr=procs; curr->type >= 0; curr++) { |
| if (curr->type == skb->nh.raw[off]) { |
| /* type specific length/alignment |
| checks will be performed in the |
| func(). */ |
| if (curr->func(skbp, off) == 0) |
| return 0; |
| break; |
| } |
| } |
| if (curr->type < 0) { |
| if (ip6_tlvopt_unknown(skbp, off) == 0) |
| return 0; |
| } |
| break; |
| } |
| off += optlen; |
| len -= optlen; |
| } |
| if (len == 0) |
| return 1; |
| bad: |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| /***************************** |
| Destination options header. |
| *****************************/ |
| |
| #ifdef CONFIG_IPV6_MIP6 |
| static int ipv6_dest_hao(struct sk_buff **skbp, int optoff) |
| { |
| struct sk_buff *skb = *skbp; |
| struct ipv6_destopt_hao *hao; |
| struct inet6_skb_parm *opt = IP6CB(skb); |
| struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb->nh.raw; |
| struct in6_addr tmp_addr; |
| int ret; |
| |
| if (opt->dsthao) { |
| LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n"); |
| goto discard; |
| } |
| opt->dsthao = opt->dst1; |
| opt->dst1 = 0; |
| |
| hao = (struct ipv6_destopt_hao *)(skb->nh.raw + optoff); |
| |
| if (hao->length != 16) { |
| LIMIT_NETDEBUG( |
| KERN_DEBUG "hao invalid option length = %d\n", hao->length); |
| goto discard; |
| } |
| |
| if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { |
| LIMIT_NETDEBUG( |
| KERN_DEBUG "hao is not an unicast addr: " NIP6_FMT "\n", NIP6(hao->addr)); |
| goto discard; |
| } |
| |
| ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr, |
| (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS); |
| if (unlikely(ret < 0)) |
| goto discard; |
| |
| if (skb_cloned(skb)) { |
| struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC); |
| if (skb2 == NULL) |
| goto discard; |
| |
| kfree_skb(skb); |
| |
| /* update all variable using below by copied skbuff */ |
| *skbp = skb = skb2; |
| hao = (struct ipv6_destopt_hao *)(skb2->nh.raw + optoff); |
| ipv6h = (struct ipv6hdr *)skb2->nh.raw; |
| } |
| |
| if (skb->ip_summed == CHECKSUM_COMPLETE) |
| skb->ip_summed = CHECKSUM_NONE; |
| |
| ipv6_addr_copy(&tmp_addr, &ipv6h->saddr); |
| ipv6_addr_copy(&ipv6h->saddr, &hao->addr); |
| ipv6_addr_copy(&hao->addr, &tmp_addr); |
| |
| if (skb->tstamp.off_sec == 0) |
| __net_timestamp(skb); |
| |
| return 1; |
| |
| discard: |
| kfree_skb(skb); |
| return 0; |
| } |
| #endif |
| |
| static struct tlvtype_proc tlvprocdestopt_lst[] = { |
| #ifdef CONFIG_IPV6_MIP6 |
| { |
| .type = IPV6_TLV_HAO, |
| .func = ipv6_dest_hao, |
| }, |
| #endif |
| {-1, NULL} |
| }; |
| |
| static int ipv6_destopt_rcv(struct sk_buff **skbp) |
| { |
| struct sk_buff *skb = *skbp; |
| struct inet6_skb_parm *opt = IP6CB(skb); |
| #ifdef CONFIG_IPV6_MIP6 |
| __u16 dstbuf; |
| #endif |
| |
| if (!pskb_may_pull(skb, (skb->h.raw-skb->data)+8) || |
| !pskb_may_pull(skb, (skb->h.raw-skb->data)+((skb->h.raw[1]+1)<<3))) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| kfree_skb(skb); |
| return -1; |
| } |
| |
| opt->lastopt = skb->h.raw - skb->nh.raw; |
| opt->dst1 = skb->h.raw - skb->nh.raw; |
| #ifdef CONFIG_IPV6_MIP6 |
| dstbuf = opt->dst1; |
| #endif |
| |
| if (ip6_parse_tlv(tlvprocdestopt_lst, skbp)) { |
| skb = *skbp; |
| skb->h.raw += ((skb->h.raw[1]+1)<<3); |
| #ifdef CONFIG_IPV6_MIP6 |
| opt->nhoff = dstbuf; |
| #else |
| opt->nhoff = opt->dst1; |
| #endif |
| return 1; |
| } |
| |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| return -1; |
| } |
| |
| static struct inet6_protocol destopt_protocol = { |
| .handler = ipv6_destopt_rcv, |
| .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
| }; |
| |
| void __init ipv6_destopt_init(void) |
| { |
| if (inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS) < 0) |
| printk(KERN_ERR "ipv6_destopt_init: Could not register protocol\n"); |
| } |
| |
| /******************************** |
| NONE header. No data in packet. |
| ********************************/ |
| |
| static int ipv6_nodata_rcv(struct sk_buff **skbp) |
| { |
| struct sk_buff *skb = *skbp; |
| |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| static struct inet6_protocol nodata_protocol = { |
| .handler = ipv6_nodata_rcv, |
| .flags = INET6_PROTO_NOPOLICY, |
| }; |
| |
| void __init ipv6_nodata_init(void) |
| { |
| if (inet6_add_protocol(&nodata_protocol, IPPROTO_NONE) < 0) |
| printk(KERN_ERR "ipv6_nodata_init: Could not register protocol\n"); |
| } |
| |
| /******************************** |
| Routing header. |
| ********************************/ |
| |
| static int ipv6_rthdr_rcv(struct sk_buff **skbp) |
| { |
| struct sk_buff *skb = *skbp; |
| struct inet6_skb_parm *opt = IP6CB(skb); |
| struct in6_addr *addr = NULL; |
| struct in6_addr daddr; |
| int n, i; |
| |
| struct ipv6_rt_hdr *hdr; |
| struct rt0_hdr *rthdr; |
| |
| if (!pskb_may_pull(skb, (skb->h.raw-skb->data)+8) || |
| !pskb_may_pull(skb, (skb->h.raw-skb->data)+((skb->h.raw[1]+1)<<3))) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| kfree_skb(skb); |
| return -1; |
| } |
| |
| hdr = (struct ipv6_rt_hdr *) skb->h.raw; |
| |
| if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr) || |
| skb->pkt_type != PACKET_HOST) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); |
| kfree_skb(skb); |
| return -1; |
| } |
| |
| looped_back: |
| if (hdr->segments_left == 0) { |
| switch (hdr->type) { |
| #ifdef CONFIG_IPV6_MIP6 |
| case IPV6_SRCRT_TYPE_2: |
| /* Silently discard type 2 header unless it was |
| * processed by own |
| */ |
| if (!addr) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); |
| kfree_skb(skb); |
| return -1; |
| } |
| break; |
| #endif |
| default: |
| break; |
| } |
| |
| opt->lastopt = skb->h.raw - skb->nh.raw; |
| opt->srcrt = skb->h.raw - skb->nh.raw; |
| skb->h.raw += (hdr->hdrlen + 1) << 3; |
| opt->dst0 = opt->dst1; |
| opt->dst1 = 0; |
| opt->nhoff = (&hdr->nexthdr) - skb->nh.raw; |
| return 1; |
| } |
| |
| switch (hdr->type) { |
| case IPV6_SRCRT_TYPE_0: |
| if (hdr->hdrlen & 0x01) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->hdrlen) - skb->nh.raw); |
| return -1; |
| } |
| break; |
| #ifdef CONFIG_IPV6_MIP6 |
| case IPV6_SRCRT_TYPE_2: |
| /* Silently discard invalid RTH type 2 */ |
| if (hdr->hdrlen != 2 || hdr->segments_left != 1) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| kfree_skb(skb); |
| return -1; |
| } |
| break; |
| #endif |
| default: |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->type) - skb->nh.raw); |
| return -1; |
| } |
| |
| /* |
| * This is the routing header forwarding algorithm from |
| * RFC 2460, page 16. |
| */ |
| |
| n = hdr->hdrlen >> 1; |
| |
| if (hdr->segments_left > n) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->segments_left) - skb->nh.raw); |
| return -1; |
| } |
| |
| /* We are about to mangle packet header. Be careful! |
| Do not damage packets queued somewhere. |
| */ |
| if (skb_cloned(skb)) { |
| struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC); |
| kfree_skb(skb); |
| /* the copy is a forwarded packet */ |
| if (skb2 == NULL) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_OUTDISCARDS); |
| return -1; |
| } |
| *skbp = skb = skb2; |
| opt = IP6CB(skb2); |
| hdr = (struct ipv6_rt_hdr *) skb2->h.raw; |
| } |
| |
| if (skb->ip_summed == CHECKSUM_COMPLETE) |
| skb->ip_summed = CHECKSUM_NONE; |
| |
| i = n - --hdr->segments_left; |
| |
| rthdr = (struct rt0_hdr *) hdr; |
| addr = rthdr->addr; |
| addr += i - 1; |
| |
| switch (hdr->type) { |
| #ifdef CONFIG_IPV6_MIP6 |
| case IPV6_SRCRT_TYPE_2: |
| if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, |
| (xfrm_address_t *)&skb->nh.ipv6h->saddr, |
| IPPROTO_ROUTING) < 0) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); |
| kfree_skb(skb); |
| return -1; |
| } |
| if (!ipv6_chk_home_addr(addr)) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); |
| kfree_skb(skb); |
| return -1; |
| } |
| break; |
| #endif |
| default: |
| break; |
| } |
| |
| if (ipv6_addr_is_multicast(addr)) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); |
| kfree_skb(skb); |
| return -1; |
| } |
| |
| ipv6_addr_copy(&daddr, addr); |
| ipv6_addr_copy(addr, &skb->nh.ipv6h->daddr); |
| ipv6_addr_copy(&skb->nh.ipv6h->daddr, &daddr); |
| |
| dst_release(xchg(&skb->dst, NULL)); |
| ip6_route_input(skb); |
| if (skb->dst->error) { |
| skb_push(skb, skb->data - skb->nh.raw); |
| dst_input(skb); |
| return -1; |
| } |
| |
| if (skb->dst->dev->flags&IFF_LOOPBACK) { |
| if (skb->nh.ipv6h->hop_limit <= 1) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
| 0, skb->dev); |
| kfree_skb(skb); |
| return -1; |
| } |
| skb->nh.ipv6h->hop_limit--; |
| goto looped_back; |
| } |
| |
| skb_push(skb, skb->data - skb->nh.raw); |
| dst_input(skb); |
| return -1; |
| } |
| |
| static struct inet6_protocol rthdr_protocol = { |
| .handler = ipv6_rthdr_rcv, |
| .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_GSO_EXTHDR, |
| }; |
| |
| void __init ipv6_rthdr_init(void) |
| { |
| if (inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING) < 0) |
| printk(KERN_ERR "ipv6_rthdr_init: Could not register protocol\n"); |
| }; |
| |
| /* |
| This function inverts received rthdr. |
| NOTE: specs allow to make it automatically only if |
| packet authenticated. |
| |
| I will not discuss it here (though, I am really pissed off at |
| this stupid requirement making rthdr idea useless) |
| |
| Actually, it creates severe problems for us. |
| Embryonic requests has no associated sockets, |
| so that user have no control over it and |
| cannot not only to set reply options, but |
| even to know, that someone wants to connect |
| without success. :-( |
| |
| For now we need to test the engine, so that I created |
| temporary (or permanent) backdoor. |
| If listening socket set IPV6_RTHDR to 2, then we invert header. |
| --ANK (980729) |
| */ |
| |
| struct ipv6_txoptions * |
| ipv6_invert_rthdr(struct sock *sk, struct ipv6_rt_hdr *hdr) |
| { |
| /* Received rthdr: |
| |
| [ H1 -> H2 -> ... H_prev ] daddr=ME |
| |
| Inverted result: |
| [ H_prev -> ... -> H1 ] daddr =sender |
| |
| Note, that IP output engine will rewrite this rthdr |
| by rotating it left by one addr. |
| */ |
| |
| int n, i; |
| struct rt0_hdr *rthdr = (struct rt0_hdr*)hdr; |
| struct rt0_hdr *irthdr; |
| struct ipv6_txoptions *opt; |
| int hdrlen = ipv6_optlen(hdr); |
| |
| if (hdr->segments_left || |
| hdr->type != IPV6_SRCRT_TYPE_0 || |
| hdr->hdrlen & 0x01) |
| return NULL; |
| |
| n = hdr->hdrlen >> 1; |
| opt = sock_kmalloc(sk, sizeof(*opt) + hdrlen, GFP_ATOMIC); |
| if (opt == NULL) |
| return NULL; |
| memset(opt, 0, sizeof(*opt)); |
| opt->tot_len = sizeof(*opt) + hdrlen; |
| opt->srcrt = (void*)(opt+1); |
| opt->opt_nflen = hdrlen; |
| |
| memcpy(opt->srcrt, hdr, sizeof(*hdr)); |
| irthdr = (struct rt0_hdr*)opt->srcrt; |
| irthdr->reserved = 0; |
| opt->srcrt->segments_left = n; |
| for (i=0; i<n; i++) |
| memcpy(irthdr->addr+i, rthdr->addr+(n-1-i), 16); |
| return opt; |
| } |
| |
| EXPORT_SYMBOL_GPL(ipv6_invert_rthdr); |
| |
| /********************************** |
| Hop-by-hop options. |
| **********************************/ |
| |
| /* Router Alert as of RFC 2711 */ |
| |
| static int ipv6_hop_ra(struct sk_buff **skbp, int optoff) |
| { |
| struct sk_buff *skb = *skbp; |
| |
| if (skb->nh.raw[optoff+1] == 2) { |
| IP6CB(skb)->ra = optoff; |
| return 1; |
| } |
| LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n", |
| skb->nh.raw[optoff+1]); |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| /* Jumbo payload */ |
| |
| static int ipv6_hop_jumbo(struct sk_buff **skbp, int optoff) |
| { |
| struct sk_buff *skb = *skbp; |
| u32 pkt_len; |
| |
| if (skb->nh.raw[optoff+1] != 4 || (optoff&3) != 2) { |
| LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
| skb->nh.raw[optoff+1]); |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| goto drop; |
| } |
| |
| pkt_len = ntohl(*(u32*)(skb->nh.raw+optoff+2)); |
| if (pkt_len <= IPV6_MAXPLEN) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
| return 0; |
| } |
| if (skb->nh.ipv6h->payload_len) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); |
| icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
| return 0; |
| } |
| |
| if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { |
| IP6_INC_STATS_BH(IPSTATS_MIB_INTRUNCATEDPKTS); |
| goto drop; |
| } |
| |
| if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) |
| goto drop; |
| |
| return 1; |
| |
| drop: |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| static struct tlvtype_proc tlvprochopopt_lst[] = { |
| { |
| .type = IPV6_TLV_ROUTERALERT, |
| .func = ipv6_hop_ra, |
| }, |
| { |
| .type = IPV6_TLV_JUMBO, |
| .func = ipv6_hop_jumbo, |
| }, |
| { -1, } |
| }; |
| |
| int ipv6_parse_hopopts(struct sk_buff **skbp) |
| { |
| struct sk_buff *skb = *skbp; |
| struct inet6_skb_parm *opt = IP6CB(skb); |
| |
| /* |
| * skb->nh.raw is equal to skb->data, and |
| * skb->h.raw - skb->nh.raw is always equal to |
| * sizeof(struct ipv6hdr) by definition of |
| * hop-by-hop options. |
| */ |
| if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) || |
| !pskb_may_pull(skb, sizeof(struct ipv6hdr) + ((skb->h.raw[1] + 1) << 3))) { |
| kfree_skb(skb); |
| return -1; |
| } |
| |
| opt->hop = sizeof(struct ipv6hdr); |
| if (ip6_parse_tlv(tlvprochopopt_lst, skbp)) { |
| skb = *skbp; |
| skb->h.raw += (skb->h.raw[1]+1)<<3; |
| opt->nhoff = sizeof(struct ipv6hdr); |
| return 1; |
| } |
| return -1; |
| } |
| |
| /* |
| * Creating outbound headers. |
| * |
| * "build" functions work when skb is filled from head to tail (datagram) |
| * "push" functions work when headers are added from tail to head (tcp) |
| * |
| * In both cases we assume, that caller reserved enough room |
| * for headers. |
| */ |
| |
| static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, |
| struct ipv6_rt_hdr *opt, |
| struct in6_addr **addr_p) |
| { |
| struct rt0_hdr *phdr, *ihdr; |
| int hops; |
| |
| ihdr = (struct rt0_hdr *) opt; |
| |
| phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3); |
| memcpy(phdr, ihdr, sizeof(struct rt0_hdr)); |
| |
| hops = ihdr->rt_hdr.hdrlen >> 1; |
| |
| if (hops > 1) |
| memcpy(phdr->addr, ihdr->addr + 1, |
| (hops - 1) * sizeof(struct in6_addr)); |
| |
| ipv6_addr_copy(phdr->addr + (hops - 1), *addr_p); |
| *addr_p = ihdr->addr; |
| |
| phdr->rt_hdr.nexthdr = *proto; |
| *proto = NEXTHDR_ROUTING; |
| } |
| |
| static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) |
| { |
| struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt)); |
| |
| memcpy(h, opt, ipv6_optlen(opt)); |
| h->nexthdr = *proto; |
| *proto = type; |
| } |
| |
| void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, |
| u8 *proto, |
| struct in6_addr **daddr) |
| { |
| if (opt->srcrt) { |
| ipv6_push_rthdr(skb, proto, opt->srcrt, daddr); |
| /* |
| * IPV6_RTHDRDSTOPTS is ignored |
| * unless IPV6_RTHDR is set (RFC3542). |
| */ |
| if (opt->dst0opt) |
| ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt); |
| } |
| if (opt->hopopt) |
| ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt); |
| } |
| |
| void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto) |
| { |
| if (opt->dst1opt) |
| ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt); |
| } |
| |
| struct ipv6_txoptions * |
| ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt) |
| { |
| struct ipv6_txoptions *opt2; |
| |
| opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC); |
| if (opt2) { |
| long dif = (char*)opt2 - (char*)opt; |
| memcpy(opt2, opt, opt->tot_len); |
| if (opt2->hopopt) |
| *((char**)&opt2->hopopt) += dif; |
| if (opt2->dst0opt) |
| *((char**)&opt2->dst0opt) += dif; |
| if (opt2->dst1opt) |
| *((char**)&opt2->dst1opt) += dif; |
| if (opt2->srcrt) |
| *((char**)&opt2->srcrt) += dif; |
| } |
| return opt2; |
| } |
| |
| EXPORT_SYMBOL_GPL(ipv6_dup_options); |
| |
| static int ipv6_renew_option(void *ohdr, |
| struct ipv6_opt_hdr __user *newopt, int newoptlen, |
| int inherit, |
| struct ipv6_opt_hdr **hdr, |
| char **p) |
| { |
| if (inherit) { |
| if (ohdr) { |
| memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr)); |
| *hdr = (struct ipv6_opt_hdr *)*p; |
| *p += CMSG_ALIGN(ipv6_optlen(*(struct ipv6_opt_hdr **)hdr)); |
| } |
| } else { |
| if (newopt) { |
| if (copy_from_user(*p, newopt, newoptlen)) |
| return -EFAULT; |
| *hdr = (struct ipv6_opt_hdr *)*p; |
| if (ipv6_optlen(*(struct ipv6_opt_hdr **)hdr) > newoptlen) |
| return -EINVAL; |
| *p += CMSG_ALIGN(newoptlen); |
| } |
| } |
| return 0; |
| } |
| |
| struct ipv6_txoptions * |
| ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, |
| int newtype, |
| struct ipv6_opt_hdr __user *newopt, int newoptlen) |
| { |
| int tot_len = 0; |
| char *p; |
| struct ipv6_txoptions *opt2; |
| int err; |
| |
| if (opt) { |
| if (newtype != IPV6_HOPOPTS && opt->hopopt) |
| tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt)); |
| if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt) |
| tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt)); |
| if (newtype != IPV6_RTHDR && opt->srcrt) |
| tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt)); |
| if (newtype != IPV6_DSTOPTS && opt->dst1opt) |
| tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt)); |
| } |
| |
| if (newopt && newoptlen) |
| tot_len += CMSG_ALIGN(newoptlen); |
| |
| if (!tot_len) |
| return NULL; |
| |
| tot_len += sizeof(*opt2); |
| opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC); |
| if (!opt2) |
| return ERR_PTR(-ENOBUFS); |
| |
| memset(opt2, 0, tot_len); |
| |
| opt2->tot_len = tot_len; |
| p = (char *)(opt2 + 1); |
| |
| err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen, |
| newtype != IPV6_HOPOPTS, |
| &opt2->hopopt, &p); |
| if (err) |
| goto out; |
| |
| err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen, |
| newtype != IPV6_RTHDRDSTOPTS, |
| &opt2->dst0opt, &p); |
| if (err) |
| goto out; |
| |
| err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen, |
| newtype != IPV6_RTHDR, |
| (struct ipv6_opt_hdr **)&opt2->srcrt, &p); |
| if (err) |
| goto out; |
| |
| err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen, |
| newtype != IPV6_DSTOPTS, |
| &opt2->dst1opt, &p); |
| if (err) |
| goto out; |
| |
| opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) + |
| (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) + |
| (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0); |
| opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0); |
| |
| return opt2; |
| out: |
| sock_kfree_s(sk, opt2, opt2->tot_len); |
| return ERR_PTR(err); |
| } |
| |
| struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, |
| struct ipv6_txoptions *opt) |
| { |
| /* |
| * ignore the dest before srcrt unless srcrt is being included. |
| * --yoshfuji |
| */ |
| if (opt && opt->dst0opt && !opt->srcrt) { |
| if (opt_space != opt) { |
| memcpy(opt_space, opt, sizeof(*opt_space)); |
| opt = opt_space; |
| } |
| opt->opt_nflen -= ipv6_optlen(opt->dst0opt); |
| opt->dst0opt = NULL; |
| } |
| |
| return opt; |
| } |
| |