diff options
| author |   Jon Loeliger <jdl@netgate.com> | 2020-01-28 07:30:28 -0600 |
|---|---|---|
| committer |   Ole Trøan <otroan@employees.org> | 2020-01-30 11:05:35 +0000 |
| commit | 65866f03d96bd41b99b1c823ea6f38cd77fac58c (patch) | |
| tree | a1c63ac21b3549ba0160e313ecee6bc275ec71c0 /src/plugins/map/ip6_map_t.c | |
| parent | 56817e2c486a26167783676774b0dea9c103b200 (diff) | |
map: Prevent IPv4 prefix spoofing during IPv6 -> IPv4
Prevent malicious packets with spoofed embedded IPv4 addresses
by limiting the IPv6 ingress packets to known MAP-T domains.
Drop spoofed packets.
Add several tests that ensure spoofing isn't allowed.
Type: fix
Fixes: fc7344f9be
Change-Id: I80a5dd10d5fe7492e3a1b04de389d649a78065e2
Signed-off-by: Jon Loeliger <jdl@netgate.com>
Diffstat (limited to 'src/plugins/map/ip6_map_t.c')
| -rw-r--r-- | src/plugins/map/ip6_map_t.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/src/plugins/map/ip6_map_t.c b/src/plugins/map/ip6_map_t.c index 95104dc78f4..e205c60e29a 100644 --- a/src/plugins/map/ip6_map_t.c +++ b/src/plugins/map/ip6_map_t.c @@ -66,7 +66,7 @@ ip6_to_ip4_set_icmp_cb (ip6_header_t * ip6, ip4_header_t * ip4, void *arg) // Security check // Note that this prevents an intermediate IPv6 router from answering // the request. - ip4_sadr = map_get_ip4 (&ip6->src_address, ctx->d->flags); + ip4_sadr = map_get_ip4 (&ip6->src_address, ctx->d->ip6_src_len); if (ip6->src_address.as_u64[0] != map_get_pfx_net (ctx->d, ip4_sadr, ctx->sender_port) || ip6->src_address.as_u64[1] != map_get_sfx_net (ctx->d, ip4_sadr, @@ -88,7 +88,7 @@ ip6_to_ip4_set_inner_icmp_cb (ip6_header_t * ip6, ip4_header_t * ip4, u32 inner_ip4_dadr; //Security check of inner packet - inner_ip4_dadr = map_get_ip4 (&ip6->dst_address, ctx->d->flags); + inner_ip4_dadr = map_get_ip4 (&ip6->dst_address, ctx->d->ip6_src_len); if (ip6->dst_address.as_u64[0] != map_get_pfx_net (ctx->d, inner_ip4_dadr, ctx->sender_port) || ip6->dst_address.as_u64[1] != map_get_sfx_net (ctx->d, @@ -305,6 +305,8 @@ ip6_map_t_fragmented (vlib_main_t * vm, /* * Translate IPv6 UDP/TCP packet to IPv4. + * Returns 0 on success. + * Returns a non-zero error code on error. */ always_inline int map_ip6_to_ip4_tcp_udp (vlib_main_t * vm, vlib_buffer_t * p, @@ -370,6 +372,16 @@ map_ip6_to_ip4_tcp_udp (vlib_main_t * vm, vlib_buffer_t * p, ip4->dst_address.as_u32 = vnet_buffer (p)->map_t.v6.daddr; ip4->src_address.as_u32 = vnet_buffer (p)->map_t.v6.saddr; + /* + * Drop spoofed packets that from a known domain source. + */ + u32 map_domain_index = -1; + u8 error = 0; + + ip4_map_get_domain (&ip4->src_address, &map_domain_index, &error); + if (error) + return error; + ip4->ip_version_and_header_length = IP4_VERSION_AND_HEADER_LENGTH_NO_OPTIONS; ip4->tos = ip6_translate_tos (ip6->ip_version_traffic_class_and_flow_label); |