diff options
| -rw-r--r-- | net/dccp/dccp.h | 3 | ||||
| -rw-r--r-- | net/dccp/ipv4.c | 38 | ||||
| -rw-r--r-- | net/dccp/output.c | 9 |
3 files changed, 28 insertions, 22 deletions
diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h index fb83454102c1..55b690ab61ae 100644 --- a/net/dccp/dccp.h +++ b/net/dccp/dccp.h @@ -242,7 +242,8 @@ extern int dccp_setsockopt(struct sock *sk, int level, int optname, char *optval, int optlen); extern void dccp_shutdown(struct sock *sk, int how); -extern int dccp_v4_checksum(struct sk_buff *skb); +extern int dccp_v4_checksum(const struct sk_buff *skb, + const u32 saddr, const u32 daddr); extern int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code); extern void dccp_send_close(struct sock *sk); diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index 083bacaecb3b..7b90606ec10e 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -802,9 +802,9 @@ static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) return sk; } -int dccp_v4_checksum(struct sk_buff *skb) +int dccp_v4_checksum(const struct sk_buff *skb, const u32 saddr, const u32 daddr) { - struct dccp_hdr* dh = dccp_hdr(skb); + const struct dccp_hdr* dh = dccp_hdr(skb); int checksum_len; u32 tmp; @@ -816,24 +816,24 @@ int dccp_v4_checksum(struct sk_buff *skb) } tmp = csum_partial((unsigned char *)dh, checksum_len, 0); - return csum_fold(tmp); + return csum_tcpudp_magic(saddr, daddr, checksum_len, IPPROTO_DCCP, tmp); } -static int dccp_v4_verify_checksum(struct sk_buff *skb) +static int dccp_v4_verify_checksum(struct sk_buff *skb, + const u32 saddr, const u32 daddr) { - struct dccp_hdr *th = dccp_hdr(skb); - const u16 remote_checksum = th->dccph_checksum; - u16 local_checksum; - - /* FIXME: don't mess with skb payload */ - th->dccph_checksum = 0; /* zero it for computation */ - - local_checksum = dccp_v4_checksum(skb); - - /* FIXME: don't mess with skb payload */ - th->dccph_checksum = remote_checksum; /* put it back */ + struct dccp_hdr *dh = dccp_hdr(skb); + int checksum_len; + u32 tmp; - return remote_checksum == local_checksum ? 0 : -1; + if (dh->dccph_cscov == 0) + checksum_len = skb->len; + else { + checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32); + checksum_len = checksum_len < skb->len ? checksum_len : skb->len; + } + tmp = csum_partial((unsigned char *)dh, checksum_len, 0); + return csum_tcpudp_magic(saddr, daddr, checksum_len, IPPROTO_DCCP, tmp) == 0 ? 0 : -1; } static struct dst_entry* dccp_v4_route_skb(struct sock *sk, @@ -902,7 +902,8 @@ void dccp_v4_ctl_send_reset(struct sk_buff *rxskb) dccp_hdr_set_seq(dh, DCCP_SKB_CB(rxskb)->dccpd_ack_seq); dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), DCCP_SKB_CB(rxskb)->dccpd_seq); - dh->dccph_checksum = dccp_v4_checksum(skb); + dh->dccph_checksum = dccp_v4_checksum(skb, rxskb->nh.iph->saddr, + rxskb->nh.iph->daddr); bh_lock_sock(dccp_ctl_socket->sk); err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk, @@ -1024,7 +1025,8 @@ static inline int dccp_invalid_packet(struct sk_buff *skb) } /* If the header checksum is incorrect, drop packet and return */ - if (dccp_v4_verify_checksum(skb) < 0) { + if (dccp_v4_verify_checksum(skb, skb->nh.iph->saddr, + skb->nh.iph->daddr) < 0) { dccp_pr_debug("header checksum is incorrect\n"); return 1; } diff --git a/net/dccp/output.c b/net/dccp/output.c index 22ca2910d4f2..4945eaa9d1a4 100644 --- a/net/dccp/output.c +++ b/net/dccp/output.c @@ -93,7 +93,8 @@ int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb) break; } - dh->dccph_checksum = dccp_v4_checksum(skb); + dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr, + inet->daddr); if (dcb->dccpd_type == DCCP_PKT_ACK || dcb->dccpd_type == DCCP_PKT_DATAACK) @@ -193,7 +194,8 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, dccp_hdr_set_seq(dh, dccp_rsk(req)->dreq_iss); dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), dccp_rsk(req)->dreq_isr); - dh->dccph_checksum = dccp_v4_checksum(skb); + dh->dccph_checksum = dccp_v4_checksum(skb, inet_rsk(req)->loc_addr, + inet_rsk(req)->rmt_addr); DCCP_INC_STATS(DCCP_MIB_OUTSEGS); return skb; @@ -242,7 +244,8 @@ struct sk_buff *dccp_make_reset(struct sock *sk, struct dst_entry *dst, dccp_hdr_reset(skb)->dccph_reset_code = code; - dh->dccph_checksum = dccp_v4_checksum(skb); + dh->dccph_checksum = dccp_v4_checksum(skb, inet_sk(sk)->saddr, + inet_sk(sk)->daddr); DCCP_INC_STATS(DCCP_MIB_OUTSEGS); return skb; |