diff options
| -rw-r--r-- | include/linux/ipv6.h | 1 | ||||
| -rw-r--r-- | include/net/rpl.h | 34 | ||||
| -rw-r--r-- | include/uapi/linux/ipv6.h | 2 | ||||
| -rw-r--r-- | net/ipv6/Makefile | 2 | ||||
| -rw-r--r-- | net/ipv6/addrconf.c | 10 | ||||
| -rw-r--r-- | net/ipv6/exthdrs.c | 201 | ||||
| -rw-r--r-- | net/ipv6/rpl.c | 123 |
7 files changed, 370 insertions, 3 deletions
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h index ea7c7906591e..2cb445a8fc9e 100644 --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -74,6 +74,7 @@ struct ipv6_devconf { __u32 addr_gen_mode; __s32 disable_policy; __s32 ndisc_tclass; + __s32 rpl_seg_enabled; struct ctl_table_header *sysctl_header; }; diff --git a/include/net/rpl.h b/include/net/rpl.h new file mode 100644 index 000000000000..d694d49a61db --- /dev/null +++ b/include/net/rpl.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * RPL implementation + * + * Author: + * (C) 2020 Alexander Aring <alex.aring@gmail.com> + */ + +#ifndef _NET_RPL_H +#define _NET_RPL_H + +#include <linux/rpl.h> + +/* Worst decompression memory usage ipv6 address (16) + pad 7 */ +#define IPV6_RPL_SRH_WORST_SWAP_SIZE (sizeof(struct in6_addr) + 7) + +static inline size_t ipv6_rpl_srh_alloc_size(unsigned char n) +{ + return sizeof(struct ipv6_rpl_sr_hdr) + + ((n + 1) * sizeof(struct in6_addr)); +} + +size_t ipv6_rpl_srh_size(unsigned char n, unsigned char cmpri, + unsigned char cmpre); + +void ipv6_rpl_srh_decompress(struct ipv6_rpl_sr_hdr *outhdr, + const struct ipv6_rpl_sr_hdr *inhdr, + const struct in6_addr *daddr, unsigned char n); + +void ipv6_rpl_srh_compress(struct ipv6_rpl_sr_hdr *outhdr, + const struct ipv6_rpl_sr_hdr *inhdr, + const struct in6_addr *daddr, unsigned char n); + +#endif /* _NET_RPL_H */ diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h index 9c0f4a92bcff..13e8751bf24a 100644 --- a/include/uapi/linux/ipv6.h +++ b/include/uapi/linux/ipv6.h @@ -40,6 +40,7 @@ struct in6_ifreq { #define IPV6_SRCRT_STRICT 0x01 /* Deprecated; will be removed */ #define IPV6_SRCRT_TYPE_0 0 /* Deprecated; will be removed */ #define IPV6_SRCRT_TYPE_2 2 /* IPv6 type 2 Routing Header */ +#define IPV6_SRCRT_TYPE_3 3 /* RPL Segment Routing with IPv6 */ #define IPV6_SRCRT_TYPE_4 4 /* Segment Routing with IPv6 */ /* @@ -187,6 +188,7 @@ enum { DEVCONF_DISABLE_POLICY, DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN, DEVCONF_NDISC_TCLASS, + DEVCONF_RPL_SEG_ENABLED, DEVCONF_MAX }; diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile index 8ccf35514015..9d3e9bd2334f 100644 --- a/net/ipv6/Makefile +++ b/net/ipv6/Makefile @@ -10,7 +10,7 @@ ipv6-objs := af_inet6.o anycast.o ip6_output.o ip6_input.o addrconf.o \ route.o ip6_fib.o ipv6_sockglue.o ndisc.o udp.o udplite.o \ raw.o icmp.o mcast.o reassembly.o tcp_ipv6.o ping.o \ exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o \ - udp_offload.o seg6.o fib6_notifier.o + udp_offload.o seg6.o fib6_notifier.o rpl.o ipv6-offload := ip6_offload.o tcpv6_offload.o exthdrs_offload.o diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 594963a7e1ec..a11fd4d67832 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -236,6 +236,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = { .enhanced_dad = 1, .addr_gen_mode = IN6_ADDR_GEN_MODE_EUI64, .disable_policy = 0, + .rpl_seg_enabled = 0, }; static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = { @@ -290,6 +291,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = { .enhanced_dad = 1, .addr_gen_mode = IN6_ADDR_GEN_MODE_EUI64, .disable_policy = 0, + .rpl_seg_enabled = 0, }; /* Check if link is ready: is it up and is a valid qdisc available */ @@ -5520,6 +5522,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf, array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode; array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy; array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass; + array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled; } static inline size_t inet6_ifla6_size(void) @@ -6901,6 +6904,13 @@ static const struct ctl_table addrconf_sysctl[] = { .extra2 = (void *)&two_five_five, }, { + .procname = "rpl_seg_enabled", + .data = &ipv6_devconf.rpl_seg_enabled, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { /* sentinel */ } }; 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 <net/seg6_hmac.h> #endif +#include <net/rpl.h> #include <linux/uaccess.h> @@ -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) { diff --git a/net/ipv6/rpl.c b/net/ipv6/rpl.c new file mode 100644 index 000000000000..dc4f20e23bf7 --- /dev/null +++ b/net/ipv6/rpl.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0-only +/** + * Authors: + * (C) 2020 Alexander Aring <alex.aring@gmail.com> + */ + +#include <net/ipv6.h> +#include <net/rpl.h> + +#define IPV6_PFXTAIL_LEN(x) (sizeof(struct in6_addr) - (x)) + +static void ipv6_rpl_addr_decompress(struct in6_addr *dst, + const struct in6_addr *daddr, + const void *post, unsigned char pfx) +{ + memcpy(dst, daddr, pfx); + memcpy(&dst->s6_addr[pfx], post, IPV6_PFXTAIL_LEN(pfx)); +} + +static void ipv6_rpl_addr_compress(void *dst, const struct in6_addr *addr, + unsigned char pfx) +{ + memcpy(dst, &addr->s6_addr[pfx], IPV6_PFXTAIL_LEN(pfx)); +} + +static void *ipv6_rpl_segdata_pos(const struct ipv6_rpl_sr_hdr *hdr, int i) +{ + return (void *)&hdr->rpl_segdata[i * IPV6_PFXTAIL_LEN(hdr->cmpri)]; +} + +size_t ipv6_rpl_srh_size(unsigned char n, unsigned char cmpri, + unsigned char cmpre) +{ + return (n * IPV6_PFXTAIL_LEN(cmpri)) + IPV6_PFXTAIL_LEN(cmpre); +} + +void ipv6_rpl_srh_decompress(struct ipv6_rpl_sr_hdr *outhdr, + const struct ipv6_rpl_sr_hdr *inhdr, + const struct in6_addr *daddr, unsigned char n) +{ + int i; + + outhdr->nexthdr = inhdr->nexthdr; + outhdr->hdrlen = (((n + 1) * sizeof(struct in6_addr)) >> 3); + outhdr->pad = 0; + outhdr->type = inhdr->type; + outhdr->segments_left = inhdr->segments_left; + outhdr->cmpri = 0; + outhdr->cmpre = 0; + + for (i = 0; i <= n; i++) + ipv6_rpl_addr_decompress(&outhdr->rpl_segaddr[i], daddr, + ipv6_rpl_segdata_pos(inhdr, i), + inhdr->cmpri); + + ipv6_rpl_addr_decompress(&outhdr->rpl_segaddr[n], daddr, + ipv6_rpl_segdata_pos(inhdr, n), + inhdr->cmpre); +} + +static unsigned char ipv6_rpl_srh_calc_cmpri(const struct ipv6_rpl_sr_hdr *inhdr, + const struct in6_addr *daddr, + unsigned char n) +{ + unsigned char plen; + int i; + + for (plen = 0; plen < sizeof(*daddr); plen++) { + for (i = 0; i <= n; i++) { + if (daddr->s6_addr[plen] != + inhdr->rpl_segaddr[i].s6_addr[plen]) + return plen; + } + } + + return plen; +} + +static unsigned char ipv6_rpl_srh_calc_cmpre(const struct in6_addr *daddr, + const struct in6_addr *last_segment) +{ + unsigned int plen; + + for (plen = 0; plen < sizeof(*daddr); plen++) { + if (daddr->s6_addr[plen] != last_segment->s6_addr[plen]) + break; + } + + return plen; +} + +void ipv6_rpl_srh_compress(struct ipv6_rpl_sr_hdr *outhdr, + const struct ipv6_rpl_sr_hdr *inhdr, + const struct in6_addr *daddr, unsigned char n) +{ + unsigned char cmpri, cmpre; + size_t seglen; + int i; + + cmpri = ipv6_rpl_srh_calc_cmpri(inhdr, daddr, n); + cmpre = ipv6_rpl_srh_calc_cmpre(daddr, &inhdr->rpl_segaddr[n]); + + outhdr->nexthdr = inhdr->nexthdr; + seglen = (n * IPV6_PFXTAIL_LEN(cmpri)) + IPV6_PFXTAIL_LEN(cmpre); + outhdr->hdrlen = seglen >> 3; + if (seglen & 0x7) { + outhdr->hdrlen++; + outhdr->pad = 8 - (seglen & 0x7); + } else { + outhdr->pad = 0; + } + outhdr->type = inhdr->type; + outhdr->segments_left = inhdr->segments_left; + outhdr->cmpri = cmpri; + outhdr->cmpre = cmpre; + + for (i = 0; i <= n; i++) + ipv6_rpl_addr_compress(ipv6_rpl_segdata_pos(outhdr, i), + &inhdr->rpl_segaddr[i], cmpri); + + ipv6_rpl_addr_compress(ipv6_rpl_segdata_pos(outhdr, n), + &inhdr->rpl_segaddr[n], cmpre); +} |