From a8eceea84a3a3504e42f6495cf462027c5d19cb0 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Thu, 12 Mar 2020 15:50:22 -0700 Subject: inet: Use fallthrough; Convert the various uses of fallthrough comments to fallthrough; Done via script Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/ And by hand: net/ipv6/ip6_fib.c has a fallthrough comment outside of an #ifdef block that causes gcc to emit a warning if converted in-place. So move the new fallthrough; inside the containing #ifdef/#endif too. Signed-off-by: Joe Perches Signed-off-by: David S. Miller --- net/ipv6/exthdrs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv6/exthdrs.c') diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index ab5add0fe6b4..bcb9f5e62808 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -97,7 +97,7 @@ static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff, */ if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) break; - /* fall through */ + fallthrough; case 2: /* send ICMP PARM PROB regardless and drop packet */ icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff); return false; -- cgit From 8610c7c6e3bd647ff98d21c8bc0580e77bc2f8b3 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Fri, 27 Mar 2020 18:00:20 -0400 Subject: net: ipv6: add support for rpl sr exthdr This patch adds rpl source routing receive handling. Everything works only if sysconf "rpl_seg_enabled" and source routing is enabled. Mostly the same behaviour as IPv6 segmentation routing. To handle compression and uncompression a rpl.c file is created which contains the necessary functionality. The receive handling will also care about IPv6 encapsulated so far it's specified as possible nexthdr in RFC 6554. Signed-off-by: Alexander Aring Signed-off-by: David S. Miller --- net/ipv6/exthdrs.c | 201 ++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 199 insertions(+), 2 deletions(-) (limited to 'net/ipv6/exthdrs.c') diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c index bcb9f5e62808..5a8bbcdcaf2b 100644 --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -48,6 +48,7 @@ #ifdef CONFIG_IPV6_SEG6_HMAC #include #endif +#include #include @@ -468,6 +469,195 @@ looped_back: return -1; } +static int ipv6_rpl_srh_rcv(struct sk_buff *skb) +{ + struct ipv6_rpl_sr_hdr *hdr, *ohdr, *chdr; + struct inet6_skb_parm *opt = IP6CB(skb); + struct net *net = dev_net(skb->dev); + struct inet6_dev *idev; + struct ipv6hdr *oldhdr; + struct in6_addr addr; + unsigned char *buf; + int accept_rpl_seg; + int i, err; + u64 n = 0; + u32 r; + + idev = __in6_dev_get(skb->dev); + + accept_rpl_seg = net->ipv6.devconf_all->rpl_seg_enabled; + if (accept_rpl_seg > idev->cnf.rpl_seg_enabled) + accept_rpl_seg = idev->cnf.rpl_seg_enabled; + + if (!accept_rpl_seg) { + kfree_skb(skb); + return -1; + } + +looped_back: + hdr = (struct ipv6_rpl_sr_hdr *)skb_transport_header(skb); + + if (hdr->segments_left == 0) { + if (hdr->nexthdr == NEXTHDR_IPV6) { + int offset = (hdr->hdrlen + 1) << 3; + + skb_postpull_rcsum(skb, skb_network_header(skb), + skb_network_header_len(skb)); + + if (!pskb_pull(skb, offset)) { + kfree_skb(skb); + return -1; + } + skb_postpull_rcsum(skb, skb_transport_header(skb), + offset); + + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + skb->encapsulation = 0; + + __skb_tunnel_rx(skb, skb->dev, net); + + netif_rx(skb); + return -1; + } + + opt->srcrt = skb_network_header_len(skb); + opt->lastopt = opt->srcrt; + skb->transport_header += (hdr->hdrlen + 1) << 3; + opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); + + return 1; + } + + if (!pskb_may_pull(skb, sizeof(*hdr))) { + kfree_skb(skb); + return -1; + } + + n = (hdr->hdrlen << 3) - hdr->pad - (16 - hdr->cmpre); + r = do_div(n, (16 - hdr->cmpri)); + /* checks if calculation was without remainder and n fits into + * unsigned char which is segments_left field. Should not be + * higher than that. + */ + if (r || (n + 1) > 255) { + kfree_skb(skb); + return -1; + } + + if (hdr->segments_left > n + 1) { + __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); + icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, + ((&hdr->segments_left) - + skb_network_header(skb))); + return -1; + } + + if (skb_cloned(skb)) { + if (pskb_expand_head(skb, IPV6_RPL_SRH_WORST_SWAP_SIZE, 0, + GFP_ATOMIC)) { + __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), + IPSTATS_MIB_OUTDISCARDS); + kfree_skb(skb); + return -1; + } + } else { + err = skb_cow_head(skb, IPV6_RPL_SRH_WORST_SWAP_SIZE); + if (unlikely(err)) { + kfree_skb(skb); + return -1; + } + } + + hdr = (struct ipv6_rpl_sr_hdr *)skb_transport_header(skb); + + if (!pskb_may_pull(skb, ipv6_rpl_srh_size(n, hdr->cmpri, + hdr->cmpre))) { + kfree_skb(skb); + return -1; + } + + hdr->segments_left--; + i = n - hdr->segments_left; + + buf = kzalloc(ipv6_rpl_srh_alloc_size(n + 1) * 2, GFP_ATOMIC); + if (unlikely(!buf)) { + kfree_skb(skb); + return -1; + } + + ohdr = (struct ipv6_rpl_sr_hdr *)buf; + ipv6_rpl_srh_decompress(ohdr, hdr, &ipv6_hdr(skb)->daddr, n); + chdr = (struct ipv6_rpl_sr_hdr *)(buf + ((ohdr->hdrlen + 1) << 3)); + + if ((ipv6_addr_type(&ipv6_hdr(skb)->daddr) & IPV6_ADDR_MULTICAST) || + (ipv6_addr_type(&ohdr->rpl_segaddr[i]) & IPV6_ADDR_MULTICAST)) { + kfree_skb(skb); + kfree(buf); + return -1; + } + + err = ipv6_chk_rpl_srh_loop(net, ohdr->rpl_segaddr, n + 1); + if (err) { + icmpv6_send(skb, ICMPV6_PARAMPROB, 0, 0); + kfree_skb(skb); + kfree(buf); + return -1; + } + + addr = ipv6_hdr(skb)->daddr; + ipv6_hdr(skb)->daddr = ohdr->rpl_segaddr[i]; + ohdr->rpl_segaddr[i] = addr; + + ipv6_rpl_srh_compress(chdr, ohdr, &ipv6_hdr(skb)->daddr, n); + + oldhdr = ipv6_hdr(skb); + + skb_pull(skb, ((hdr->hdrlen + 1) << 3)); + skb_postpull_rcsum(skb, oldhdr, + sizeof(struct ipv6hdr) + ((hdr->hdrlen + 1) << 3)); + skb_push(skb, ((chdr->hdrlen + 1) << 3) + sizeof(struct ipv6hdr)); + skb_reset_network_header(skb); + skb_mac_header_rebuild(skb); + skb_set_transport_header(skb, sizeof(struct ipv6hdr)); + + memmove(ipv6_hdr(skb), oldhdr, sizeof(struct ipv6hdr)); + memcpy(skb_transport_header(skb), chdr, (chdr->hdrlen + 1) << 3); + + ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); + skb_postpush_rcsum(skb, ipv6_hdr(skb), + sizeof(struct ipv6hdr) + ((chdr->hdrlen + 1) << 3)); + + kfree(buf); + + skb_dst_drop(skb); + + ip6_route_input(skb); + + if (skb_dst(skb)->error) { + dst_input(skb); + return -1; + } + + if (skb_dst(skb)->dev->flags & IFF_LOOPBACK) { + if (ipv6_hdr(skb)->hop_limit <= 1) { + __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); + icmpv6_send(skb, ICMPV6_TIME_EXCEED, + ICMPV6_EXC_HOPLIMIT, 0); + kfree_skb(skb); + return -1; + } + ipv6_hdr(skb)->hop_limit--; + + skb_pull(skb, sizeof(struct ipv6hdr)); + goto looped_back; + } + + dst_input(skb); + + return -1; +} + /******************************** Routing header. ********************************/ @@ -506,9 +696,16 @@ static int ipv6_rthdr_rcv(struct sk_buff *skb) return -1; } - /* segment routing */ - if (hdr->type == IPV6_SRCRT_TYPE_4) + switch (hdr->type) { + case IPV6_SRCRT_TYPE_4: + /* segment routing */ return ipv6_srh_rcv(skb); + case IPV6_SRCRT_TYPE_3: + /* rpl segment routing */ + return ipv6_rpl_srh_rcv(skb); + default: + break; + } looped_back: if (hdr->segments_left == 0) { -- cgit