diff options
| -rw-r--r-- | drivers/net/macvtap.c | 3 | ||||
| -rw-r--r-- | drivers/net/tun.c | 6 | ||||
| -rw-r--r-- | include/net/ipv6.h | 2 | ||||
| -rw-r--r-- | net/ipv6/output_core.c | 34 |
4 files changed, 44 insertions, 1 deletions
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 2aeaa61ece0..6f226de655a 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -16,6 +16,7 @@ #include <linux/idr.h> #include <linux/fs.h> +#include <net/ipv6.h> #include <net/net_namespace.h> #include <net/rtnetlink.h> #include <net/sock.h> @@ -572,6 +573,8 @@ static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb, pr_warn_once("macvtap: %s: using disabled UFO feature; please fix this program\n", current->comm); gso_type = SKB_GSO_UDP; + if (skb->protocol == htons(ETH_P_IPV6)) + ipv6_proxy_select_ident(skb); break; default: return -EINVAL; diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 280d3d2a979..7302398f0b1 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -65,6 +65,7 @@ #include <linux/nsproxy.h> #include <linux/virtio_net.h> #include <linux/rcupdate.h> +#include <net/ipv6.h> #include <net/net_namespace.h> #include <net/netns/generic.h> #include <net/rtnetlink.h> @@ -1139,6 +1140,8 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, break; } + skb_reset_network_header(skb); + if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) { pr_debug("GSO!\n"); switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { @@ -1159,6 +1162,8 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, current->comm); } skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + if (skb->protocol == htons(ETH_P_IPV6)) + ipv6_proxy_select_ident(skb); break; } default: @@ -1189,7 +1194,6 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; } - skb_reset_network_header(skb); skb_probe_transport_header(skb, 0); rxhash = skb_get_hash(skb); diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 97f47201243..4292929392b 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -671,6 +671,8 @@ static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_add return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr)); } +void ipv6_proxy_select_ident(struct sk_buff *skb); + int ip6_dst_hoplimit(struct dst_entry *dst); static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6, diff --git a/net/ipv6/output_core.c b/net/ipv6/output_core.c index fc24c390af0..97f41a3e68d 100644 --- a/net/ipv6/output_core.c +++ b/net/ipv6/output_core.c @@ -3,11 +3,45 @@ * not configured or static. These functions are needed by GSO/GRO implementation. */ #include <linux/export.h> +#include <net/ip.h> #include <net/ipv6.h> #include <net/ip6_fib.h> #include <net/addrconf.h> #include <net/secure_seq.h> +/* This function exists only for tap drivers that must support broken + * clients requesting UFO without specifying an IPv6 fragment ID. + * + * This is similar to ipv6_select_ident() but we use an independent hash + * seed to limit information leakage. + * + * The network header must be set before calling this. + */ +void ipv6_proxy_select_ident(struct sk_buff *skb) +{ + static u32 ip6_proxy_idents_hashrnd __read_mostly; + struct in6_addr buf[2]; + struct in6_addr *addrs; + u32 hash, id; + + addrs = skb_header_pointer(skb, + skb_network_offset(skb) + + offsetof(struct ipv6hdr, saddr), + sizeof(buf), buf); + if (!addrs) + return; + + net_get_random_once(&ip6_proxy_idents_hashrnd, + sizeof(ip6_proxy_idents_hashrnd)); + + hash = __ipv6_addr_jhash(&addrs[1], ip6_proxy_idents_hashrnd); + hash = __ipv6_addr_jhash(&addrs[0], hash); + + id = ip_idents_reserve(hash, 1); + skb_shinfo(skb)->ip6_frag_id = htonl(id); +} +EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident); + int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) { u16 offset = sizeof(struct ipv6hdr); |