diff options
Diffstat (limited to 'net/ipv6/ndisc.c')
| -rw-r--r-- | net/ipv6/ndisc.c | 362 |
1 files changed, 181 insertions, 181 deletions
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 6574175795df..76ef4353d518 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -143,16 +143,12 @@ struct neigh_table nd_tbl = { .gc_thresh3 = 1024, }; -static inline int ndisc_opt_addr_space(struct net_device *dev) +static void ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data) { - return NDISC_OPT_SPACE(dev->addr_len + ndisc_addr_option_pad(dev->type)); -} - -static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len, - unsigned short addr_type) -{ - int pad = ndisc_addr_option_pad(addr_type); - int space = NDISC_OPT_SPACE(data_len + pad); + int pad = ndisc_addr_option_pad(skb->dev->type); + int data_len = skb->dev->addr_len; + int space = ndisc_opt_addr_space(skb->dev); + u8 *opt = skb_put(skb, space); opt[0] = type; opt[1] = space>>3; @@ -166,7 +162,6 @@ static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len, opt += data_len; if ((space -= data_len) > 0) memset(opt, 0, space); - return opt + space; } static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur, @@ -370,91 +365,88 @@ static void pndisc_destructor(struct pneigh_entry *n) ipv6_dev_mc_dec(dev, &maddr); } -static struct sk_buff *ndisc_build_skb(struct net_device *dev, - const struct in6_addr *daddr, - const struct in6_addr *saddr, - struct icmp6hdr *icmp6h, - const struct in6_addr *target, - int llinfo) +static struct sk_buff *ndisc_alloc_skb(struct net_device *dev, + int len) { - struct net *net = dev_net(dev); - struct sock *sk = net->ipv6.ndisc_sk; - struct sk_buff *skb; - struct icmp6hdr *hdr; int hlen = LL_RESERVED_SPACE(dev); int tlen = dev->needed_tailroom; - int len; + struct sock *sk = dev_net(dev)->ipv6.ndisc_sk; + struct sk_buff *skb; int err; - u8 *opt; - - if (!dev->addr_len) - llinfo = 0; - - len = sizeof(struct icmp6hdr) + (target ? sizeof(*target) : 0); - if (llinfo) - len += ndisc_opt_addr_space(dev); skb = sock_alloc_send_skb(sk, - (MAX_HEADER + sizeof(struct ipv6hdr) + - len + hlen + tlen), + hlen + sizeof(struct ipv6hdr) + len + tlen, 1, &err); if (!skb) { - ND_PRINTK(0, err, "ND: %s failed to allocate an skb, err=%d\n", + ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb, err=%d\n", __func__, err); return NULL; } - skb_reserve(skb, hlen); - ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len); + skb->protocol = htons(ETH_P_IPV6); + skb->dev = dev; - skb->transport_header = skb->tail; - skb_put(skb, len); + skb_reserve(skb, hlen + sizeof(struct ipv6hdr)); + skb_reset_transport_header(skb); - hdr = (struct icmp6hdr *)skb_transport_header(skb); - memcpy(hdr, icmp6h, sizeof(*hdr)); + return skb; +} - opt = skb_transport_header(skb) + sizeof(struct icmp6hdr); - if (target) { - *(struct in6_addr *)opt = *target; - opt += sizeof(*target); - } +static void ip6_nd_hdr(struct sk_buff *skb, + const struct in6_addr *saddr, + const struct in6_addr *daddr, + int hop_limit, int len) +{ + struct ipv6hdr *hdr; - if (llinfo) - ndisc_fill_addr_option(opt, llinfo, dev->dev_addr, - dev->addr_len, dev->type); + skb_push(skb, sizeof(*hdr)); + skb_reset_network_header(skb); + hdr = ipv6_hdr(skb); - hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len, - IPPROTO_ICMPV6, - csum_partial(hdr, - len, 0)); + ip6_flow_hdr(hdr, 0, 0); - return skb; + hdr->payload_len = htons(len); + hdr->nexthdr = IPPROTO_ICMPV6; + hdr->hop_limit = hop_limit; + + hdr->saddr = *saddr; + hdr->daddr = *daddr; } -static void ndisc_send_skb(struct sk_buff *skb, struct net_device *dev, - struct neighbour *neigh, +static void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr, - const struct in6_addr *saddr, - struct icmp6hdr *icmp6h) + const struct in6_addr *saddr) { - struct flowi6 fl6; - struct dst_entry *dst; - struct net *net = dev_net(dev); + struct dst_entry *dst = skb_dst(skb); + struct net *net = dev_net(skb->dev); struct sock *sk = net->ipv6.ndisc_sk; struct inet6_dev *idev; int err; + struct icmp6hdr *icmp6h = icmp6_hdr(skb); u8 type; type = icmp6h->icmp6_type; - icmpv6_flow_init(sk, &fl6, type, saddr, daddr, dev->ifindex); - dst = icmp6_dst_alloc(dev, neigh, &fl6); - if (IS_ERR(dst)) { - kfree_skb(skb); - return; + if (!dst) { + struct sock *sk = net->ipv6.ndisc_sk; + struct flowi6 fl6; + + icmpv6_flow_init(sk, &fl6, type, saddr, daddr, skb->dev->ifindex); + dst = icmp6_dst_alloc(skb->dev, &fl6); + if (IS_ERR(dst)) { + kfree_skb(skb); + return; + } + + skb_dst_set(skb, dst); } - skb_dst_set(skb, dst); + icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len, + IPPROTO_ICMPV6, + csum_partial(icmp6h, + skb->len, 0)); + + ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len); rcu_read_lock(); idev = __in6_dev_get(dst->dev); @@ -470,36 +462,17 @@ static void ndisc_send_skb(struct sk_buff *skb, struct net_device *dev, rcu_read_unlock(); } -/* - * Send a Neighbour Discover packet - */ -static void __ndisc_send(struct net_device *dev, - struct neighbour *neigh, - const struct in6_addr *daddr, - const struct in6_addr *saddr, - struct icmp6hdr *icmp6h, const struct in6_addr *target, - int llinfo) -{ - struct sk_buff *skb; - - skb = ndisc_build_skb(dev, daddr, saddr, icmp6h, target, llinfo); - if (!skb) - return; - - ndisc_send_skb(skb, dev, neigh, daddr, saddr, icmp6h); -} - static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh, const struct in6_addr *daddr, const struct in6_addr *solicited_addr, - int router, int solicited, int override, int inc_opt) + bool router, bool solicited, bool override, bool inc_opt) { + struct sk_buff *skb; struct in6_addr tmpaddr; struct inet6_ifaddr *ifp; const struct in6_addr *src_addr; - struct icmp6hdr icmp6h = { - .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT, - }; + struct nd_msg *msg; + int optlen = 0; /* for anycast or proxy, solicited_addr != src_addr */ ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1); @@ -517,13 +490,32 @@ static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh, src_addr = &tmpaddr; } - icmp6h.icmp6_router = router; - icmp6h.icmp6_solicited = solicited; - icmp6h.icmp6_override = override; + if (!dev->addr_len) + inc_opt = 0; + if (inc_opt) + optlen += ndisc_opt_addr_space(dev); + + skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); + if (!skb) + return; - __ndisc_send(dev, neigh, daddr, src_addr, - &icmp6h, solicited_addr, - inc_opt ? ND_OPT_TARGET_LL_ADDR : 0); + msg = (struct nd_msg *)skb_put(skb, sizeof(*msg)); + *msg = (struct nd_msg) { + .icmph = { + .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT, + .icmp6_router = router, + .icmp6_solicited = solicited, + .icmp6_override = override, + }, + .target = *solicited_addr, + }; + + if (inc_opt) + ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, + dev->dev_addr); + + + ndisc_send_skb(skb, daddr, src_addr); } static void ndisc_send_unsol_na(struct net_device *dev) @@ -551,10 +543,11 @@ void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh, const struct in6_addr *solicit, const struct in6_addr *daddr, const struct in6_addr *saddr) { + struct sk_buff *skb; struct in6_addr addr_buf; - struct icmp6hdr icmp6h = { - .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION, - }; + int inc_opt = dev->addr_len; + int optlen = 0; + struct nd_msg *msg; if (saddr == NULL) { if (ipv6_get_lladdr(dev, &addr_buf, @@ -563,18 +556,37 @@ void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh, saddr = &addr_buf; } - __ndisc_send(dev, neigh, daddr, saddr, - &icmp6h, solicit, - !ipv6_addr_any(saddr) ? ND_OPT_SOURCE_LL_ADDR : 0); + if (ipv6_addr_any(saddr)) + inc_opt = 0; + if (inc_opt) + optlen += ndisc_opt_addr_space(dev); + + skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); + if (!skb) + return; + + msg = (struct nd_msg *)skb_put(skb, sizeof(*msg)); + *msg = (struct nd_msg) { + .icmph = { + .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION, + }, + .target = *solicit, + }; + + if (inc_opt) + ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, + dev->dev_addr); + + ndisc_send_skb(skb, daddr, saddr); } void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr, const struct in6_addr *daddr) { - struct icmp6hdr icmp6h = { - .icmp6_type = NDISC_ROUTER_SOLICITATION, - }; + struct sk_buff *skb; + struct rs_msg *msg; int send_sllao = dev->addr_len; + int optlen = 0; #ifdef CONFIG_IPV6_OPTIMISTIC_DAD /* @@ -598,9 +610,27 @@ void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr, } } #endif - __ndisc_send(dev, NULL, daddr, saddr, - &icmp6h, NULL, - send_sllao ? ND_OPT_SOURCE_LL_ADDR : 0); + if (!dev->addr_len) + send_sllao = 0; + if (send_sllao) + optlen += ndisc_opt_addr_space(dev); + + skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); + if (!skb) + return; + + msg = (struct rs_msg *)skb_put(skb, sizeof(*msg)); + *msg = (struct rs_msg) { + .icmph = { + .icmp6_type = NDISC_ROUTER_SOLICITATION, + }, + }; + + if (send_sllao) + ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR, + dev->dev_addr); + + ndisc_send_skb(skb, daddr, saddr); } @@ -676,6 +706,11 @@ static void ndisc_recv_ns(struct sk_buff *skb) bool inc; int is_router = -1; + if (skb->len < sizeof(struct nd_msg)) { + ND_PRINTK(2, warn, "NS: packet too short\n"); + return; + } + if (ipv6_addr_is_multicast(&msg->target)) { ND_PRINTK(2, warn, "NS: multicast target address\n"); return; @@ -685,11 +720,7 @@ static void ndisc_recv_ns(struct sk_buff *skb) * RFC2461 7.1.1: * DAD has to be destined for solicited node multicast address. */ - if (dad && - !(daddr->s6_addr32[0] == htonl(0xff020000) && - daddr->s6_addr32[1] == htonl(0x00000000) && - daddr->s6_addr32[2] == htonl(0x00000001) && - daddr->s6_addr [12] == 0xff )) { + if (dad && !ipv6_addr_is_solict_mult(daddr)) { ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n"); return; } @@ -780,11 +811,11 @@ static void ndisc_recv_ns(struct sk_buff *skb) } if (is_router < 0) - is_router = !!idev->cnf.forwarding; + is_router = idev->cnf.forwarding; if (dad) { ndisc_send_na(dev, NULL, &in6addr_linklocal_allnodes, &msg->target, - is_router, 0, (ifp != NULL), 1); + !!is_router, false, (ifp != NULL), true); goto out; } @@ -805,8 +836,8 @@ static void ndisc_recv_ns(struct sk_buff *skb) NEIGH_UPDATE_F_OVERRIDE); if (neigh || !dev->header_ops) { ndisc_send_na(dev, neigh, saddr, &msg->target, - is_router, - 1, (ifp != NULL && inc), inc); + !!is_router, + true, (ifp != NULL && inc), inc); if (neigh) neigh_release(neigh); } @@ -1350,25 +1381,34 @@ static void ndisc_redirect_rcv(struct sk_buff *skb) icmpv6_notify(skb, NDISC_REDIRECT, 0, 0); } +static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb, + struct sk_buff *orig_skb, + int rd_len) +{ + u8 *opt = skb_put(skb, rd_len); + + memset(opt, 0, 8); + *(opt++) = ND_OPT_REDIRECT_HDR; + *(opt++) = (rd_len >> 3); + opt += 6; + + memcpy(opt, ipv6_hdr(orig_skb), rd_len - 8); +} + void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) { struct net_device *dev = skb->dev; struct net *net = dev_net(dev); struct sock *sk = net->ipv6.ndisc_sk; - int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr); + int optlen = 0; struct inet_peer *peer; struct sk_buff *buff; - struct icmp6hdr *icmph; + struct rd_msg *msg; struct in6_addr saddr_buf; - struct in6_addr *addrp; struct rt6_info *rt; struct dst_entry *dst; - struct inet6_dev *idev; struct flowi6 fl6; - u8 *opt; - int hlen, tlen; int rd_len; - int err; u8 ha_buf[MAX_ADDR_LEN], *ha = NULL; bool ret; @@ -1424,7 +1464,7 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) memcpy(ha_buf, neigh->ha, dev->addr_len); read_unlock_bh(&neigh->lock); ha = ha_buf; - len += ndisc_opt_addr_space(dev); + optlen += ndisc_opt_addr_space(dev); } else read_unlock_bh(&neigh->lock); @@ -1432,80 +1472,40 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) } rd_len = min_t(unsigned int, - IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8); + IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen, + skb->len + 8); rd_len &= ~0x7; - len += rd_len; - - hlen = LL_RESERVED_SPACE(dev); - tlen = dev->needed_tailroom; - buff = sock_alloc_send_skb(sk, - (MAX_HEADER + sizeof(struct ipv6hdr) + - len + hlen + tlen), - 1, &err); - if (buff == NULL) { - ND_PRINTK(0, err, - "Redirect: %s failed to allocate an skb, err=%d\n", - __func__, err); - goto release; - } - - skb_reserve(buff, hlen); - ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr, - IPPROTO_ICMPV6, len); - - skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data); - skb_put(buff, len); - icmph = icmp6_hdr(buff); - - memset(icmph, 0, sizeof(struct icmp6hdr)); - icmph->icmp6_type = NDISC_REDIRECT; + optlen += rd_len; - /* - * copy target and destination addresses - */ - - addrp = (struct in6_addr *)(icmph + 1); - *addrp = *target; - addrp++; - *addrp = ipv6_hdr(skb)->daddr; + buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen); + if (!buff) + goto release; - opt = (u8*) (addrp + 1); + msg = (struct rd_msg *)skb_put(buff, sizeof(*msg)); + *msg = (struct rd_msg) { + .icmph = { + .icmp6_type = NDISC_REDIRECT, + }, + .target = *target, + .dest = ipv6_hdr(skb)->daddr, + }; /* * include target_address option */ if (ha) - opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha, - dev->addr_len, dev->type); + ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR, ha); /* * build redirect option and copy skb over to the new packet. */ - memset(opt, 0, 8); - *(opt++) = ND_OPT_REDIRECT_HDR; - *(opt++) = (rd_len >> 3); - opt += 6; - - memcpy(opt, ipv6_hdr(skb), rd_len - 8); - - icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr, - len, IPPROTO_ICMPV6, - csum_partial(icmph, len, 0)); + if (rd_len) + ndisc_fill_redirect_hdr_option(buff, skb, rd_len); skb_dst_set(buff, dst); - rcu_read_lock(); - idev = __in6_dev_get(dst->dev); - IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); - err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, buff, NULL, dst->dev, - dst_output); - if (!err) { - ICMP6MSGOUT_INC_STATS(net, idev, NDISC_REDIRECT); - ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS); - } - - rcu_read_unlock(); + ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf); return; release: @@ -1522,7 +1522,7 @@ int ndisc_rcv(struct sk_buff *skb) { struct nd_msg *msg; - if (!pskb_may_pull(skb, skb->len)) + if (skb_linearize(skb)) return 0; msg = (struct nd_msg *)skb_transport_header(skb); |