mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1406 lines
33 KiB
1406 lines
33 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* Extension Header handling for IPv6 |
|
* Linux INET6 implementation |
|
* |
|
* Authors: |
|
* Pedro Roque <[email protected]> |
|
* Andi Kleen <[email protected]> |
|
* Alexey Kuznetsov <[email protected]> |
|
*/ |
|
|
|
/* 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/net.h> |
|
#include <linux/netdevice.h> |
|
#include <linux/in6.h> |
|
#include <linux/icmpv6.h> |
|
#include <linux/slab.h> |
|
#include <linux/export.h> |
|
|
|
#include <net/dst.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> |
|
#include <net/calipso.h> |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
#include <net/xfrm.h> |
|
#endif |
|
#include <linux/seg6.h> |
|
#include <net/seg6.h> |
|
#ifdef CONFIG_IPV6_SEG6_HMAC |
|
#include <net/seg6_hmac.h> |
|
#endif |
|
#include <net/rpl.h> |
|
#include <linux/ioam6.h> |
|
#include <net/ioam6.h> |
|
#include <net/dst_metadata.h> |
|
|
|
#include <linux/uaccess.h> |
|
|
|
/********************* |
|
Generic functions |
|
*********************/ |
|
|
|
/* An unknown option is detected, decide what to do */ |
|
|
|
static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff, |
|
bool disallow_unknowns) |
|
{ |
|
if (disallow_unknowns) { |
|
/* If unknown TLVs are disallowed by configuration |
|
* then always silently drop packet. Note this also |
|
* means no ICMP parameter problem is sent which |
|
* could be a good property to mitigate a reflection DOS |
|
* attack. |
|
*/ |
|
|
|
goto drop; |
|
} |
|
|
|
switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) { |
|
case 0: /* ignore */ |
|
return true; |
|
|
|
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(&ipv6_hdr(skb)->daddr)) |
|
break; |
|
fallthrough; |
|
case 2: /* send ICMP PARM PROB regardless and drop packet */ |
|
icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff); |
|
return false; |
|
} |
|
|
|
drop: |
|
kfree_skb(skb); |
|
return false; |
|
} |
|
|
|
static bool ipv6_hop_ra(struct sk_buff *skb, int optoff); |
|
static bool ipv6_hop_ioam(struct sk_buff *skb, int optoff); |
|
static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff); |
|
static bool ipv6_hop_calipso(struct sk_buff *skb, int optoff); |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
static bool ipv6_dest_hao(struct sk_buff *skb, int optoff); |
|
#endif |
|
|
|
/* Parse tlv encoded option header (hop-by-hop or destination) */ |
|
|
|
static bool ip6_parse_tlv(bool hopbyhop, |
|
struct sk_buff *skb, |
|
int max_count) |
|
{ |
|
int len = (skb_transport_header(skb)[1] + 1) << 3; |
|
const unsigned char *nh = skb_network_header(skb); |
|
int off = skb_network_header_len(skb); |
|
bool disallow_unknowns = false; |
|
int tlv_count = 0; |
|
int padlen = 0; |
|
|
|
if (unlikely(max_count < 0)) { |
|
disallow_unknowns = true; |
|
max_count = -max_count; |
|
} |
|
|
|
if (skb_transport_offset(skb) + len > skb_headlen(skb)) |
|
goto bad; |
|
|
|
off += 2; |
|
len -= 2; |
|
|
|
while (len > 0) { |
|
int optlen, i; |
|
|
|
if (nh[off] == IPV6_TLV_PAD1) { |
|
padlen++; |
|
if (padlen > 7) |
|
goto bad; |
|
off++; |
|
len--; |
|
continue; |
|
} |
|
if (len < 2) |
|
goto bad; |
|
optlen = nh[off + 1] + 2; |
|
if (optlen > len) |
|
goto bad; |
|
|
|
if (nh[off] == IPV6_TLV_PADN) { |
|
/* RFC 2460 states that the purpose of PadN is |
|
* to align the containing header to multiples |
|
* of 8. 7 is therefore the highest valid value. |
|
* See also RFC 4942, Section 2.1.9.5. |
|
*/ |
|
padlen += optlen; |
|
if (padlen > 7) |
|
goto bad; |
|
/* RFC 4942 recommends receiving hosts to |
|
* actively check PadN payload to contain |
|
* only zeroes. |
|
*/ |
|
for (i = 2; i < optlen; i++) { |
|
if (nh[off + i] != 0) |
|
goto bad; |
|
} |
|
} else { |
|
tlv_count++; |
|
if (tlv_count > max_count) |
|
goto bad; |
|
|
|
if (hopbyhop) { |
|
switch (nh[off]) { |
|
case IPV6_TLV_ROUTERALERT: |
|
if (!ipv6_hop_ra(skb, off)) |
|
return false; |
|
break; |
|
case IPV6_TLV_IOAM: |
|
if (!ipv6_hop_ioam(skb, off)) |
|
return false; |
|
break; |
|
case IPV6_TLV_JUMBO: |
|
if (!ipv6_hop_jumbo(skb, off)) |
|
return false; |
|
break; |
|
case IPV6_TLV_CALIPSO: |
|
if (!ipv6_hop_calipso(skb, off)) |
|
return false; |
|
break; |
|
default: |
|
if (!ip6_tlvopt_unknown(skb, off, |
|
disallow_unknowns)) |
|
return false; |
|
break; |
|
} |
|
} else { |
|
switch (nh[off]) { |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
case IPV6_TLV_HAO: |
|
if (!ipv6_dest_hao(skb, off)) |
|
return false; |
|
break; |
|
#endif |
|
default: |
|
if (!ip6_tlvopt_unknown(skb, off, |
|
disallow_unknowns)) |
|
return false; |
|
break; |
|
} |
|
} |
|
padlen = 0; |
|
} |
|
off += optlen; |
|
len -= optlen; |
|
} |
|
|
|
if (len == 0) |
|
return true; |
|
bad: |
|
kfree_skb(skb); |
|
return false; |
|
} |
|
|
|
/***************************** |
|
Destination options header. |
|
*****************************/ |
|
|
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
static bool ipv6_dest_hao(struct sk_buff *skb, int optoff) |
|
{ |
|
struct ipv6_destopt_hao *hao; |
|
struct inet6_skb_parm *opt = IP6CB(skb); |
|
struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
|
int ret; |
|
|
|
if (opt->dsthao) { |
|
net_dbg_ratelimited("hao duplicated\n"); |
|
goto discard; |
|
} |
|
opt->dsthao = opt->dst1; |
|
opt->dst1 = 0; |
|
|
|
hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff); |
|
|
|
if (hao->length != 16) { |
|
net_dbg_ratelimited("hao invalid option length = %d\n", |
|
hao->length); |
|
goto discard; |
|
} |
|
|
|
if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) { |
|
net_dbg_ratelimited("hao is not an unicast addr: %pI6\n", |
|
&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)) { |
|
if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
|
goto discard; |
|
|
|
/* update all variable using below by copied skbuff */ |
|
hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + |
|
optoff); |
|
ipv6h = ipv6_hdr(skb); |
|
} |
|
|
|
if (skb->ip_summed == CHECKSUM_COMPLETE) |
|
skb->ip_summed = CHECKSUM_NONE; |
|
|
|
swap(ipv6h->saddr, hao->addr); |
|
|
|
if (skb->tstamp == 0) |
|
__net_timestamp(skb); |
|
|
|
return true; |
|
|
|
discard: |
|
kfree_skb(skb); |
|
return false; |
|
} |
|
#endif |
|
|
|
static int ipv6_destopt_rcv(struct sk_buff *skb) |
|
{ |
|
struct inet6_dev *idev = __in6_dev_get(skb->dev); |
|
struct inet6_skb_parm *opt = IP6CB(skb); |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
__u16 dstbuf; |
|
#endif |
|
struct dst_entry *dst = skb_dst(skb); |
|
struct net *net = dev_net(skb->dev); |
|
int extlen; |
|
|
|
if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
|
!pskb_may_pull(skb, (skb_transport_offset(skb) + |
|
((skb_transport_header(skb)[1] + 1) << 3)))) { |
|
__IP6_INC_STATS(dev_net(dst->dev), idev, |
|
IPSTATS_MIB_INHDRERRORS); |
|
fail_and_free: |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
|
|
extlen = (skb_transport_header(skb)[1] + 1) << 3; |
|
if (extlen > net->ipv6.sysctl.max_dst_opts_len) |
|
goto fail_and_free; |
|
|
|
opt->lastopt = opt->dst1 = skb_network_header_len(skb); |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
dstbuf = opt->dst1; |
|
#endif |
|
|
|
if (ip6_parse_tlv(false, skb, net->ipv6.sysctl.max_dst_opts_cnt)) { |
|
skb->transport_header += extlen; |
|
opt = IP6CB(skb); |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
opt->nhoff = dstbuf; |
|
#else |
|
opt->nhoff = opt->dst1; |
|
#endif |
|
return 1; |
|
} |
|
|
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
|
return -1; |
|
} |
|
|
|
static void seg6_update_csum(struct sk_buff *skb) |
|
{ |
|
struct ipv6_sr_hdr *hdr; |
|
struct in6_addr *addr; |
|
__be32 from, to; |
|
|
|
/* srh is at transport offset and seg_left is already decremented |
|
* but daddr is not yet updated with next segment |
|
*/ |
|
|
|
hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb); |
|
addr = hdr->segments + hdr->segments_left; |
|
|
|
hdr->segments_left++; |
|
from = *(__be32 *)hdr; |
|
|
|
hdr->segments_left--; |
|
to = *(__be32 *)hdr; |
|
|
|
/* update skb csum with diff resulting from seg_left decrement */ |
|
|
|
update_csum_diff4(skb, from, to); |
|
|
|
/* compute csum diff between current and next segment and update */ |
|
|
|
update_csum_diff16(skb, (__be32 *)(&ipv6_hdr(skb)->daddr), |
|
(__be32 *)addr); |
|
} |
|
|
|
static int ipv6_srh_rcv(struct sk_buff *skb) |
|
{ |
|
struct inet6_skb_parm *opt = IP6CB(skb); |
|
struct net *net = dev_net(skb->dev); |
|
struct ipv6_sr_hdr *hdr; |
|
struct inet6_dev *idev; |
|
struct in6_addr *addr; |
|
int accept_seg6; |
|
|
|
hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb); |
|
|
|
idev = __in6_dev_get(skb->dev); |
|
|
|
accept_seg6 = net->ipv6.devconf_all->seg6_enabled; |
|
if (accept_seg6 > idev->cnf.seg6_enabled) |
|
accept_seg6 = idev->cnf.seg6_enabled; |
|
|
|
if (!accept_seg6) { |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
|
|
#ifdef CONFIG_IPV6_SEG6_HMAC |
|
if (!seg6_hmac_validate_skb(skb)) { |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
#endif |
|
|
|
looped_back: |
|
if (hdr->segments_left == 0) { |
|
if (hdr->nexthdr == NEXTHDR_IPV6 || hdr->nexthdr == NEXTHDR_IPV4) { |
|
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; |
|
if (hdr->nexthdr == NEXTHDR_IPV4) |
|
skb->protocol = htons(ETH_P_IP); |
|
__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 (hdr->segments_left >= (hdr->hdrlen >> 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, 0, 0, GFP_ATOMIC)) { |
|
__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
|
IPSTATS_MIB_OUTDISCARDS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
} |
|
|
|
hdr = (struct ipv6_sr_hdr *)skb_transport_header(skb); |
|
|
|
hdr->segments_left--; |
|
addr = hdr->segments + hdr->segments_left; |
|
|
|
skb_push(skb, sizeof(struct ipv6hdr)); |
|
|
|
if (skb->ip_summed == CHECKSUM_COMPLETE) |
|
seg6_update_csum(skb); |
|
|
|
ipv6_hdr(skb)->daddr = *addr; |
|
|
|
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; |
|
} |
|
|
|
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 = kcalloc(struct_size(hdr, segments.addr, n + 2), 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. |
|
********************************/ |
|
|
|
/* called with rcu_read_lock() */ |
|
static int ipv6_rthdr_rcv(struct sk_buff *skb) |
|
{ |
|
struct inet6_dev *idev = __in6_dev_get(skb->dev); |
|
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; |
|
struct net *net = dev_net(skb->dev); |
|
int accept_source_route = net->ipv6.devconf_all->accept_source_route; |
|
|
|
if (idev && accept_source_route > idev->cnf.accept_source_route) |
|
accept_source_route = idev->cnf.accept_source_route; |
|
|
|
if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) || |
|
!pskb_may_pull(skb, (skb_transport_offset(skb) + |
|
((skb_transport_header(skb)[1] + 1) << 3)))) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
|
|
hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
|
|
|
if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) || |
|
skb->pkt_type != PACKET_HOST) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
|
|
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) { |
|
switch (hdr->type) { |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
case IPV6_SRCRT_TYPE_2: |
|
/* Silently discard type 2 header unless it was |
|
* processed by own |
|
*/ |
|
if (!addr) { |
|
__IP6_INC_STATS(net, idev, |
|
IPSTATS_MIB_INADDRERRORS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
break; |
|
#endif |
|
default: |
|
break; |
|
} |
|
|
|
opt->lastopt = opt->srcrt = skb_network_header_len(skb); |
|
skb->transport_header += (hdr->hdrlen + 1) << 3; |
|
opt->dst0 = opt->dst1; |
|
opt->dst1 = 0; |
|
opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb); |
|
return 1; |
|
} |
|
|
|
switch (hdr->type) { |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
case IPV6_SRCRT_TYPE_2: |
|
if (accept_source_route < 0) |
|
goto unknown_rh; |
|
/* Silently discard invalid RTH type 2 */ |
|
if (hdr->hdrlen != 2 || hdr->segments_left != 1) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
break; |
|
#endif |
|
default: |
|
goto unknown_rh; |
|
} |
|
|
|
/* |
|
* This is the routing header forwarding algorithm from |
|
* RFC 2460, page 16. |
|
*/ |
|
|
|
n = hdr->hdrlen >> 1; |
|
|
|
if (hdr->segments_left > n) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
|
((&hdr->segments_left) - |
|
skb_network_header(skb))); |
|
return -1; |
|
} |
|
|
|
/* We are about to mangle packet header. Be careful! |
|
Do not damage packets queued somewhere. |
|
*/ |
|
if (skb_cloned(skb)) { |
|
/* the copy is a forwarded packet */ |
|
if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { |
|
__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), |
|
IPSTATS_MIB_OUTDISCARDS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb); |
|
} |
|
|
|
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) { |
|
#if IS_ENABLED(CONFIG_IPV6_MIP6) |
|
case IPV6_SRCRT_TYPE_2: |
|
if (xfrm6_input_addr(skb, (xfrm_address_t *)addr, |
|
(xfrm_address_t *)&ipv6_hdr(skb)->saddr, |
|
IPPROTO_ROUTING) < 0) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
break; |
|
#endif |
|
default: |
|
break; |
|
} |
|
|
|
if (ipv6_addr_is_multicast(addr)) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS); |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
|
|
daddr = *addr; |
|
*addr = ipv6_hdr(skb)->daddr; |
|
ipv6_hdr(skb)->daddr = daddr; |
|
|
|
skb_dst_drop(skb); |
|
ip6_route_input(skb); |
|
if (skb_dst(skb)->error) { |
|
skb_push(skb, skb->data - skb_network_header(skb)); |
|
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--; |
|
goto looped_back; |
|
} |
|
|
|
skb_push(skb, skb->data - skb_network_header(skb)); |
|
dst_input(skb); |
|
return -1; |
|
|
|
unknown_rh: |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, |
|
(&hdr->type) - skb_network_header(skb)); |
|
return -1; |
|
} |
|
|
|
static const struct inet6_protocol rthdr_protocol = { |
|
.handler = ipv6_rthdr_rcv, |
|
.flags = INET6_PROTO_NOPOLICY, |
|
}; |
|
|
|
static const struct inet6_protocol destopt_protocol = { |
|
.handler = ipv6_destopt_rcv, |
|
.flags = INET6_PROTO_NOPOLICY, |
|
}; |
|
|
|
static const struct inet6_protocol nodata_protocol = { |
|
.handler = dst_discard, |
|
.flags = INET6_PROTO_NOPOLICY, |
|
}; |
|
|
|
int __init ipv6_exthdrs_init(void) |
|
{ |
|
int ret; |
|
|
|
ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING); |
|
if (ret) |
|
goto out; |
|
|
|
ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS); |
|
if (ret) |
|
goto out_rthdr; |
|
|
|
ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE); |
|
if (ret) |
|
goto out_destopt; |
|
|
|
out: |
|
return ret; |
|
out_destopt: |
|
inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); |
|
out_rthdr: |
|
inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); |
|
goto out; |
|
}; |
|
|
|
void ipv6_exthdrs_exit(void) |
|
{ |
|
inet6_del_protocol(&nodata_protocol, IPPROTO_NONE); |
|
inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS); |
|
inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING); |
|
} |
|
|
|
/********************************** |
|
Hop-by-hop options. |
|
**********************************/ |
|
|
|
/* |
|
* Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input(). |
|
*/ |
|
static inline struct net *ipv6_skb_net(struct sk_buff *skb) |
|
{ |
|
return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev); |
|
} |
|
|
|
/* Router Alert as of RFC 2711 */ |
|
|
|
static bool ipv6_hop_ra(struct sk_buff *skb, int optoff) |
|
{ |
|
const unsigned char *nh = skb_network_header(skb); |
|
|
|
if (nh[optoff + 1] == 2) { |
|
IP6CB(skb)->flags |= IP6SKB_ROUTERALERT; |
|
memcpy(&IP6CB(skb)->ra, nh + optoff + 2, sizeof(IP6CB(skb)->ra)); |
|
return true; |
|
} |
|
net_dbg_ratelimited("ipv6_hop_ra: wrong RA length %d\n", |
|
nh[optoff + 1]); |
|
kfree_skb(skb); |
|
return false; |
|
} |
|
|
|
/* IOAM */ |
|
|
|
static bool ipv6_hop_ioam(struct sk_buff *skb, int optoff) |
|
{ |
|
struct ioam6_trace_hdr *trace; |
|
struct ioam6_namespace *ns; |
|
struct ioam6_hdr *hdr; |
|
|
|
/* Bad alignment (must be 4n-aligned) */ |
|
if (optoff & 3) |
|
goto drop; |
|
|
|
/* Ignore if IOAM is not enabled on ingress */ |
|
if (!__in6_dev_get(skb->dev)->cnf.ioam6_enabled) |
|
goto ignore; |
|
|
|
/* Truncated Option header */ |
|
hdr = (struct ioam6_hdr *)(skb_network_header(skb) + optoff); |
|
if (hdr->opt_len < 2) |
|
goto drop; |
|
|
|
switch (hdr->type) { |
|
case IOAM6_TYPE_PREALLOC: |
|
/* Truncated Pre-allocated Trace header */ |
|
if (hdr->opt_len < 2 + sizeof(*trace)) |
|
goto drop; |
|
|
|
/* Malformed Pre-allocated Trace header */ |
|
trace = (struct ioam6_trace_hdr *)((u8 *)hdr + sizeof(*hdr)); |
|
if (hdr->opt_len < 2 + sizeof(*trace) + trace->remlen * 4) |
|
goto drop; |
|
|
|
/* Ignore if the IOAM namespace is unknown */ |
|
ns = ioam6_namespace(ipv6_skb_net(skb), trace->namespace_id); |
|
if (!ns) |
|
goto ignore; |
|
|
|
if (!skb_valid_dst(skb)) |
|
ip6_route_input(skb); |
|
|
|
ioam6_fill_trace_data(skb, ns, trace, true); |
|
break; |
|
default: |
|
break; |
|
} |
|
|
|
ignore: |
|
return true; |
|
|
|
drop: |
|
kfree_skb(skb); |
|
return false; |
|
} |
|
|
|
/* Jumbo payload */ |
|
|
|
static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff) |
|
{ |
|
const unsigned char *nh = skb_network_header(skb); |
|
struct inet6_dev *idev = __in6_dev_get_safely(skb->dev); |
|
struct net *net = ipv6_skb_net(skb); |
|
u32 pkt_len; |
|
|
|
if (nh[optoff + 1] != 4 || (optoff & 3) != 2) { |
|
net_dbg_ratelimited("ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n", |
|
nh[optoff+1]); |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
|
goto drop; |
|
} |
|
|
|
pkt_len = ntohl(*(__be32 *)(nh + optoff + 2)); |
|
if (pkt_len <= IPV6_MAXPLEN) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2); |
|
return false; |
|
} |
|
if (ipv6_hdr(skb)->payload_len) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); |
|
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff); |
|
return false; |
|
} |
|
|
|
if (pkt_len > skb->len - sizeof(struct ipv6hdr)) { |
|
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INTRUNCATEDPKTS); |
|
goto drop; |
|
} |
|
|
|
if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) |
|
goto drop; |
|
|
|
IP6CB(skb)->flags |= IP6SKB_JUMBOGRAM; |
|
return true; |
|
|
|
drop: |
|
kfree_skb(skb); |
|
return false; |
|
} |
|
|
|
/* CALIPSO RFC 5570 */ |
|
|
|
static bool ipv6_hop_calipso(struct sk_buff *skb, int optoff) |
|
{ |
|
const unsigned char *nh = skb_network_header(skb); |
|
|
|
if (nh[optoff + 1] < 8) |
|
goto drop; |
|
|
|
if (nh[optoff + 6] * 4 + 8 > nh[optoff + 1]) |
|
goto drop; |
|
|
|
if (!calipso_validate(skb, nh + optoff)) |
|
goto drop; |
|
|
|
return true; |
|
|
|
drop: |
|
kfree_skb(skb); |
|
return false; |
|
} |
|
|
|
int ipv6_parse_hopopts(struct sk_buff *skb) |
|
{ |
|
struct inet6_skb_parm *opt = IP6CB(skb); |
|
struct net *net = dev_net(skb->dev); |
|
int extlen; |
|
|
|
/* |
|
* skb_network_header(skb) is equal to skb->data, and |
|
* skb_network_header_len(skb) 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_transport_header(skb)[1] + 1) << 3)))) { |
|
fail_and_free: |
|
kfree_skb(skb); |
|
return -1; |
|
} |
|
|
|
extlen = (skb_transport_header(skb)[1] + 1) << 3; |
|
if (extlen > net->ipv6.sysctl.max_hbh_opts_len) |
|
goto fail_and_free; |
|
|
|
opt->flags |= IP6SKB_HOPBYHOP; |
|
if (ip6_parse_tlv(true, skb, net->ipv6.sysctl.max_hbh_opts_cnt)) { |
|
skb->transport_header += extlen; |
|
opt = IP6CB(skb); |
|
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_rthdr0(struct sk_buff *skb, u8 *proto, |
|
struct ipv6_rt_hdr *opt, |
|
struct in6_addr **addr_p, struct in6_addr *saddr) |
|
{ |
|
struct rt0_hdr *phdr, *ihdr; |
|
int hops; |
|
|
|
ihdr = (struct rt0_hdr *) opt; |
|
|
|
phdr = 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)); |
|
|
|
phdr->addr[hops - 1] = **addr_p; |
|
*addr_p = ihdr->addr; |
|
|
|
phdr->rt_hdr.nexthdr = *proto; |
|
*proto = NEXTHDR_ROUTING; |
|
} |
|
|
|
static void ipv6_push_rthdr4(struct sk_buff *skb, u8 *proto, |
|
struct ipv6_rt_hdr *opt, |
|
struct in6_addr **addr_p, struct in6_addr *saddr) |
|
{ |
|
struct ipv6_sr_hdr *sr_phdr, *sr_ihdr; |
|
int plen, hops; |
|
|
|
sr_ihdr = (struct ipv6_sr_hdr *)opt; |
|
plen = (sr_ihdr->hdrlen + 1) << 3; |
|
|
|
sr_phdr = skb_push(skb, plen); |
|
memcpy(sr_phdr, sr_ihdr, sizeof(struct ipv6_sr_hdr)); |
|
|
|
hops = sr_ihdr->first_segment + 1; |
|
memcpy(sr_phdr->segments + 1, sr_ihdr->segments + 1, |
|
(hops - 1) * sizeof(struct in6_addr)); |
|
|
|
sr_phdr->segments[0] = **addr_p; |
|
*addr_p = &sr_ihdr->segments[sr_ihdr->segments_left]; |
|
|
|
if (sr_ihdr->hdrlen > hops * 2) { |
|
int tlvs_offset, tlvs_length; |
|
|
|
tlvs_offset = (1 + hops * 2) << 3; |
|
tlvs_length = (sr_ihdr->hdrlen - hops * 2) << 3; |
|
memcpy((char *)sr_phdr + tlvs_offset, |
|
(char *)sr_ihdr + tlvs_offset, tlvs_length); |
|
} |
|
|
|
#ifdef CONFIG_IPV6_SEG6_HMAC |
|
if (sr_has_hmac(sr_phdr)) { |
|
struct net *net = NULL; |
|
|
|
if (skb->dev) |
|
net = dev_net(skb->dev); |
|
else if (skb->sk) |
|
net = sock_net(skb->sk); |
|
|
|
WARN_ON(!net); |
|
|
|
if (net) |
|
seg6_push_hmac(net, saddr, sr_phdr); |
|
} |
|
#endif |
|
|
|
sr_phdr->nexthdr = *proto; |
|
*proto = NEXTHDR_ROUTING; |
|
} |
|
|
|
static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto, |
|
struct ipv6_rt_hdr *opt, |
|
struct in6_addr **addr_p, struct in6_addr *saddr) |
|
{ |
|
switch (opt->type) { |
|
case IPV6_SRCRT_TYPE_0: |
|
case IPV6_SRCRT_STRICT: |
|
case IPV6_SRCRT_TYPE_2: |
|
ipv6_push_rthdr0(skb, proto, opt, addr_p, saddr); |
|
break; |
|
case IPV6_SRCRT_TYPE_4: |
|
ipv6_push_rthdr4(skb, proto, opt, addr_p, saddr); |
|
break; |
|
default: |
|
break; |
|
} |
|
} |
|
|
|
static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt) |
|
{ |
|
struct ipv6_opt_hdr *h = 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, struct in6_addr *saddr) |
|
{ |
|
if (opt->srcrt) { |
|
ipv6_push_rthdr(skb, proto, opt->srcrt, daddr, saddr); |
|
/* |
|
* 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); |
|
} |
|
EXPORT_SYMBOL(ipv6_push_frag_opts); |
|
|
|
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; |
|
refcount_set(&opt2->refcnt, 1); |
|
} |
|
return opt2; |
|
} |
|
EXPORT_SYMBOL_GPL(ipv6_dup_options); |
|
|
|
static void ipv6_renew_option(int renewtype, |
|
struct ipv6_opt_hdr **dest, |
|
struct ipv6_opt_hdr *old, |
|
struct ipv6_opt_hdr *new, |
|
int newtype, char **p) |
|
{ |
|
struct ipv6_opt_hdr *src; |
|
|
|
src = (renewtype == newtype ? new : old); |
|
if (!src) |
|
return; |
|
|
|
memcpy(*p, src, ipv6_optlen(src)); |
|
*dest = (struct ipv6_opt_hdr *)*p; |
|
*p += CMSG_ALIGN(ipv6_optlen(*dest)); |
|
} |
|
|
|
/** |
|
* ipv6_renew_options - replace a specific ext hdr with a new one. |
|
* |
|
* @sk: sock from which to allocate memory |
|
* @opt: original options |
|
* @newtype: option type to replace in @opt |
|
* @newopt: new option of type @newtype to replace (user-mem) |
|
* |
|
* Returns a new set of options which is a copy of @opt with the |
|
* option type @newtype replaced with @newopt. |
|
* |
|
* @opt may be NULL, in which case a new set of options is returned |
|
* containing just @newopt. |
|
* |
|
* @newopt may be NULL, in which case the specified option type is |
|
* not copied into the new set of options. |
|
* |
|
* The new set of options is allocated from the socket option memory |
|
* buffer of @sk. |
|
*/ |
|
struct ipv6_txoptions * |
|
ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt, |
|
int newtype, struct ipv6_opt_hdr *newopt) |
|
{ |
|
int tot_len = 0; |
|
char *p; |
|
struct ipv6_txoptions *opt2; |
|
|
|
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) |
|
tot_len += CMSG_ALIGN(ipv6_optlen(newopt)); |
|
|
|
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); |
|
refcount_set(&opt2->refcnt, 1); |
|
opt2->tot_len = tot_len; |
|
p = (char *)(opt2 + 1); |
|
|
|
ipv6_renew_option(IPV6_HOPOPTS, &opt2->hopopt, |
|
(opt ? opt->hopopt : NULL), |
|
newopt, newtype, &p); |
|
ipv6_renew_option(IPV6_RTHDRDSTOPTS, &opt2->dst0opt, |
|
(opt ? opt->dst0opt : NULL), |
|
newopt, newtype, &p); |
|
ipv6_renew_option(IPV6_RTHDR, |
|
(struct ipv6_opt_hdr **)&opt2->srcrt, |
|
(opt ? (struct ipv6_opt_hdr *)opt->srcrt : NULL), |
|
newopt, newtype, &p); |
|
ipv6_renew_option(IPV6_DSTOPTS, &opt2->dst1opt, |
|
(opt ? opt->dst1opt : NULL), |
|
newopt, newtype, &p); |
|
|
|
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; |
|
} |
|
|
|
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; |
|
} |
|
EXPORT_SYMBOL_GPL(ipv6_fixup_options); |
|
|
|
/** |
|
* fl6_update_dst - update flowi destination address with info given |
|
* by srcrt option, if any. |
|
* |
|
* @fl6: flowi6 for which daddr is to be updated |
|
* @opt: struct ipv6_txoptions in which to look for srcrt opt |
|
* @orig: copy of original daddr address if modified |
|
* |
|
* Returns NULL if no txoptions or no srcrt, otherwise returns orig |
|
* and initial value of fl6->daddr set in orig |
|
*/ |
|
struct in6_addr *fl6_update_dst(struct flowi6 *fl6, |
|
const struct ipv6_txoptions *opt, |
|
struct in6_addr *orig) |
|
{ |
|
if (!opt || !opt->srcrt) |
|
return NULL; |
|
|
|
*orig = fl6->daddr; |
|
|
|
switch (opt->srcrt->type) { |
|
case IPV6_SRCRT_TYPE_0: |
|
case IPV6_SRCRT_STRICT: |
|
case IPV6_SRCRT_TYPE_2: |
|
fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr; |
|
break; |
|
case IPV6_SRCRT_TYPE_4: |
|
{ |
|
struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)opt->srcrt; |
|
|
|
fl6->daddr = srh->segments[srh->segments_left]; |
|
break; |
|
} |
|
default: |
|
return NULL; |
|
} |
|
|
|
return orig; |
|
} |
|
EXPORT_SYMBOL_GPL(fl6_update_dst);
|
|
|