diff options
| -rw-r--r-- | net/core/skbuff.c | 140 |
1 files changed, 50 insertions, 90 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 465a01c97c76..8b52dfc56c0e 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3566,15 +3566,47 @@ static int skb_maybe_pull_tail(struct sk_buff *skb, unsigned int len, return 0; } +#define MAX_TCP_HDR_LEN (15 * 4) + +static __sum16 *skb_checksum_setup_ip(struct sk_buff *skb, + typeof(IPPROTO_IP) proto, + unsigned int off) +{ + switch (proto) { + int err; + + case IPPROTO_TCP: + err = skb_maybe_pull_tail(skb, off + sizeof(struct tcphdr), + off + MAX_TCP_HDR_LEN); + if (!err && !skb_partial_csum_set(skb, off, + offsetof(struct tcphdr, + check))) + err = -EPROTO; + return err ? ERR_PTR(err) : &tcp_hdr(skb)->check; + + case IPPROTO_UDP: + err = skb_maybe_pull_tail(skb, off + sizeof(struct udphdr), + off + sizeof(struct udphdr)); + if (!err && !skb_partial_csum_set(skb, off, + offsetof(struct udphdr, + check))) + err = -EPROTO; + return err ? ERR_PTR(err) : &udp_hdr(skb)->check; + } + + return ERR_PTR(-EPROTO); +} + /* This value should be large enough to cover a tagged ethernet header plus * maximally sized IP and TCP or UDP headers. */ #define MAX_IP_HDR_LEN 128 -static int skb_checksum_setup_ip(struct sk_buff *skb, bool recalculate) +static int skb_checksum_setup_ipv4(struct sk_buff *skb, bool recalculate) { unsigned int off; bool fragment; + __sum16 *csum; int err; fragment = false; @@ -3595,51 +3627,15 @@ static int skb_checksum_setup_ip(struct sk_buff *skb, bool recalculate) if (fragment) goto out; - switch (ip_hdr(skb)->protocol) { - case IPPROTO_TCP: - err = skb_maybe_pull_tail(skb, - off + sizeof(struct tcphdr), - MAX_IP_HDR_LEN); - if (err < 0) - goto out; - - if (!skb_partial_csum_set(skb, off, - offsetof(struct tcphdr, check))) { - err = -EPROTO; - goto out; - } - - if (recalculate) - tcp_hdr(skb)->check = - ~csum_tcpudp_magic(ip_hdr(skb)->saddr, - ip_hdr(skb)->daddr, - skb->len - off, - IPPROTO_TCP, 0); - break; - case IPPROTO_UDP: - err = skb_maybe_pull_tail(skb, - off + sizeof(struct udphdr), - MAX_IP_HDR_LEN); - if (err < 0) - goto out; - - if (!skb_partial_csum_set(skb, off, - offsetof(struct udphdr, check))) { - err = -EPROTO; - goto out; - } - - if (recalculate) - udp_hdr(skb)->check = - ~csum_tcpudp_magic(ip_hdr(skb)->saddr, - ip_hdr(skb)->daddr, - skb->len - off, - IPPROTO_UDP, 0); - break; - default: - goto out; - } + csum = skb_checksum_setup_ip(skb, ip_hdr(skb)->protocol, off); + if (IS_ERR(csum)) + return PTR_ERR(csum); + if (recalculate) + *csum = ~csum_tcpudp_magic(ip_hdr(skb)->saddr, + ip_hdr(skb)->daddr, + skb->len - off, + ip_hdr(skb)->protocol, 0); err = 0; out: @@ -3662,6 +3658,7 @@ static int skb_checksum_setup_ipv6(struct sk_buff *skb, bool recalculate) unsigned int len; bool fragment; bool done; + __sum16 *csum; fragment = false; done = false; @@ -3739,51 +3736,14 @@ static int skb_checksum_setup_ipv6(struct sk_buff *skb, bool recalculate) if (!done || fragment) goto out; - switch (nexthdr) { - case IPPROTO_TCP: - err = skb_maybe_pull_tail(skb, - off + sizeof(struct tcphdr), - MAX_IPV6_HDR_LEN); - if (err < 0) - goto out; - - if (!skb_partial_csum_set(skb, off, - offsetof(struct tcphdr, check))) { - err = -EPROTO; - goto out; - } - - if (recalculate) - tcp_hdr(skb)->check = - ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, - &ipv6_hdr(skb)->daddr, - skb->len - off, - IPPROTO_TCP, 0); - break; - case IPPROTO_UDP: - err = skb_maybe_pull_tail(skb, - off + sizeof(struct udphdr), - MAX_IPV6_HDR_LEN); - if (err < 0) - goto out; - - if (!skb_partial_csum_set(skb, off, - offsetof(struct udphdr, check))) { - err = -EPROTO; - goto out; - } - - if (recalculate) - udp_hdr(skb)->check = - ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, - &ipv6_hdr(skb)->daddr, - skb->len - off, - IPPROTO_UDP, 0); - break; - default: - goto out; - } + csum = skb_checksum_setup_ip(skb, nexthdr, off); + if (IS_ERR(csum)) + return PTR_ERR(csum); + if (recalculate) + *csum = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr, + skb->len - off, nexthdr, 0); err = 0; out: @@ -3801,7 +3761,7 @@ int skb_checksum_setup(struct sk_buff *skb, bool recalculate) switch (skb->protocol) { case htons(ETH_P_IP): - err = skb_checksum_setup_ip(skb, recalculate); + err = skb_checksum_setup_ipv4(skb, recalculate); break; case htons(ETH_P_IPV6): |