diff options
| -rw-r--r-- | src/compat/compat.h | 122 | ||||
| -rw-r--r-- | src/device.c | 4 | ||||
| -rwxr-xr-x | src/tests/netns.sh | 11 |
3 files changed, 101 insertions, 36 deletions
diff --git a/src/compat/compat.h b/src/compat/compat.h index 948d3fe..5978fe9 100644 --- a/src/compat/compat.h +++ b/src/compat/compat.h @@ -932,6 +932,94 @@ static inline void skb_mark_not_on_list(struct sk_buff *skb) #define chacha20_neon zinc_chacha20_neon #endif +#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0) +#include <linux/skbuff.h> +static inline int skb_ensure_writable(struct sk_buff *skb, int write_len) +{ + if (!pskb_may_pull(skb, write_len)) + return -ENOMEM; + + if (!skb_cloned(skb) || skb_clone_writable(skb, write_len)) + return 0; + + return pskb_expand_head(skb, 0, 0, GFP_ATOMIC); +} +#endif + +#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 6, 0) +#if IS_ENABLED(CONFIG_NF_NAT) +#include <linux/ip.h> +#include <linux/icmpv6.h> +#include <net/ipv6.h> +#include <net/icmp.h> +#include <net/netfilter/nf_conntrack.h> +#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 1, 0) +#include <net/netfilter/nf_nat_core.h> +#endif +static inline void icmp_ndo_send(struct sk_buff *skb_in, int type, int code, __be32 info) +{ + struct sk_buff *cloned_skb = NULL; + enum ip_conntrack_info ctinfo; + struct nf_conn *ct; + __be32 orig_ip; + + ct = nf_ct_get(skb_in, &ctinfo); + if (!ct || !(ct->status & IPS_SRC_NAT)) { + icmp_send(skb_in, type, code, info); + return; + } + + if (skb_shared(skb_in)) + skb_in = cloned_skb = skb_clone(skb_in, GFP_ATOMIC); + + if (unlikely(!skb_in || skb_network_header(skb_in) < skb_in->head || + (skb_network_header(skb_in) + sizeof(struct iphdr)) > + skb_tail_pointer(skb_in) || skb_ensure_writable(skb_in, + skb_network_offset(skb_in) + sizeof(struct iphdr)))) + goto out; + + orig_ip = ip_hdr(skb_in)->saddr; + ip_hdr(skb_in)->saddr = ct->tuplehash[0].tuple.src.u3.ip; + icmp_send(skb_in, type, code, info); + ip_hdr(skb_in)->saddr = orig_ip; +out: + consume_skb(cloned_skb); +} +static inline void icmpv6_ndo_send(struct sk_buff *skb_in, u8 type, u8 code, __u32 info) +{ + struct sk_buff *cloned_skb = NULL; + enum ip_conntrack_info ctinfo; + struct in6_addr orig_ip; + struct nf_conn *ct; + + ct = nf_ct_get(skb_in, &ctinfo); + if (!ct || !(ct->status & IPS_SRC_NAT)) { + icmpv6_send(skb_in, type, code, info); + return; + } + + if (skb_shared(skb_in)) + skb_in = cloned_skb = skb_clone(skb_in, GFP_ATOMIC); + + if (unlikely(!skb_in || skb_network_header(skb_in) < skb_in->head || + (skb_network_header(skb_in) + sizeof(struct ipv6hdr)) > + skb_tail_pointer(skb_in) || skb_ensure_writable(skb_in, + skb_network_offset(skb_in) + sizeof(struct ipv6hdr)))) + goto out; + + orig_ip = ipv6_hdr(skb_in)->saddr; + ipv6_hdr(skb_in)->saddr = ct->tuplehash[0].tuple.src.u3.in6; + icmpv6_send(skb_in, type, code, info); + ipv6_hdr(skb_in)->saddr = orig_ip; +out: + consume_skb(cloned_skb); +} +#else +#define icmp_ndo_send icmp_send +#define icmpv6_ndo_send icmpv6_send +#endif +#endif + #if defined(ISUBUNTU1604) #include <linux/siphash.h> #ifndef _WG_LINUX_SIPHASH_H @@ -956,40 +1044,6 @@ static inline void skb_mark_not_on_list(struct sk_buff *skb) #define BUILD_BUG_ON(x) #endif -/* https://lkml.kernel.org/r/20170624021727.17835-1-Jason@zx2c4.com */ -#if IS_ENABLED(CONFIG_NF_CONNTRACK) -#include <linux/ip.h> -#include <linux/icmpv6.h> -#include <net/ipv6.h> -#include <net/icmp.h> -#include <net/netfilter/nf_conntrack.h> -#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 1, 0) -#include <net/netfilter/nf_nat_core.h> -#endif -static inline void new_icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info) -{ - enum ip_conntrack_info ctinfo; - struct nf_conn *ct = nf_ct_get(skb_in, &ctinfo); - if (skb_network_header(skb_in) < skb_in->head || (skb_network_header(skb_in) + sizeof(struct iphdr)) > skb_tail_pointer(skb_in)) - return; - if (ct) - ip_hdr(skb_in)->saddr = ct->tuplehash[0].tuple.src.u3.ip; - icmp_send(skb_in, type, code, info); -} -static inline void new_icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info) -{ - enum ip_conntrack_info ctinfo; - struct nf_conn *ct = nf_ct_get(skb, &ctinfo); - if (skb_network_header(skb) < skb->head || (skb_network_header(skb) + sizeof(struct ipv6hdr)) > skb_tail_pointer(skb)) - return; - if (ct) - ipv6_hdr(skb)->saddr = ct->tuplehash[0].tuple.src.u3.in6; - icmpv6_send(skb, type, code, info); -} -#define icmp_send(a,b,c,d) new_icmp_send(a,b,c,d) -#define icmpv6_send(a,b,c,d) new_icmpv6_send(a,b,c,d) -#endif - /* PaX compatibility */ #ifdef CONSTIFY_PLUGIN #include <linux/cache.h> diff --git a/src/device.c b/src/device.c index e888ac3..2883bad 100644 --- a/src/device.c +++ b/src/device.c @@ -211,9 +211,9 @@ err_peer: err: ++dev->stats.tx_errors; if (skb->protocol == htons(ETH_P_IP)) - icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); + icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); else if (skb->protocol == htons(ETH_P_IPV6)) - icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0); + icmpv6_ndo_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0); kfree_skb(skb); return ret; } diff --git a/src/tests/netns.sh b/src/tests/netns.sh index 315ccc4..ba5f83a 100755 --- a/src/tests/netns.sh +++ b/src/tests/netns.sh @@ -24,6 +24,7 @@ set -e exec 3>&1 +export LANG=C export WG_HIDE_KEYS=never netns0="wg-test-$$-0" netns1="wg-test-$$-1" @@ -300,7 +301,17 @@ if [[ $(ip1 -4 rule show all) == *suppress_prefixlength* ]]; then n1 ping -W 1 -c 100 -f abab::1111 fi +# Have ns2 NAT into wg0 packets from ns0, but return an icmp error along the right route. +n2 iptables -t nat -A POSTROUTING -s 10.0.0.0/24 -d 192.168.241.0/24 -j SNAT --to 192.168.241.2 +n0 iptables -t filter -A INPUT \! -s 10.0.0.0/24 -i vethrs -j DROP # Manual rpfilter just to be explicit. +n2 bash -c 'printf 1 > /proc/sys/net/ipv4/ip_forward' +ip0 -4 route add 192.168.241.1 via 10.0.0.100 +n2 wg set wg0 peer "$pub1" remove +[[ $(! n0 ping -W 1 -c 1 192.168.241.1 || false) == *"From 10.0.0.100 icmp_seq=1 Destination Host Unreachable"* ]] + n0 iptables -t nat -F +n0 iptables -t filter -F +n2 iptables -t nat -F ip0 link del vethrc ip0 link del vethrs ip1 link del wg0 |