[DCCP]: Retrieve packet sequence number for error reporting

This fixes a problem when analysing erroneous packets in dccp_v{4,6}_err:
* dccp_hdr_seq currently takes an skb
* however, the transport headers in the skb are shifted, due to the
  preceding IPv4/v6 header.
Fixed for v4 and v6 by changing dccp_hdr_seq to take a struct dccp_hdr as
argument. Verified that the correct sequence number is now reported in the
error handler.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Gerrit Renker 2007-10-24 10:12:09 -02:00 committed by Arnaldo Carvalho de Melo
parent 03cf786c4e
commit fde20105f3
3 changed files with 8 additions and 10 deletions

View File

@ -270,10 +270,9 @@ static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen)
return memset(skb_transport_header(skb), 0, headlen);
}
static inline struct dccp_hdr_ext *dccp_hdrx(const struct sk_buff *skb)
static inline struct dccp_hdr_ext *dccp_hdrx(const struct dccp_hdr *dh)
{
return (struct dccp_hdr_ext *)(skb_transport_header(skb) +
sizeof(struct dccp_hdr));
return (struct dccp_hdr_ext *)((unsigned char *)dh + sizeof(*dh));
}
static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
@ -287,13 +286,12 @@ static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
return __dccp_basic_hdr_len(dh);
}
static inline __u64 dccp_hdr_seq(const struct sk_buff *skb)
static inline __u64 dccp_hdr_seq(const struct dccp_hdr *dh)
{
const struct dccp_hdr *dh = dccp_hdr(skb);
__u64 seq_nr = ntohs(dh->dccph_seq);
if (dh->dccph_x != 0)
seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(skb)->dccph_seq_low);
seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(dh)->dccph_seq_low);
else
seq_nr += (u32)dh->dccph_seq2 << 16;

View File

@ -241,7 +241,7 @@ static void dccp_v4_err(struct sk_buff *skb, u32 info)
goto out;
dp = dccp_sk(sk);
seq = dccp_hdr_seq(skb);
seq = dccp_hdr_seq(dh);
if (sk->sk_state != DCCP_LISTEN &&
!between48(seq, dp->dccps_swl, dp->dccps_swh)) {
NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
@ -795,7 +795,7 @@ static int dccp_v4_rcv(struct sk_buff *skb)
dh = dccp_hdr(skb);
DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb);
DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
dccp_pr_debug("%8.8s "

View File

@ -173,7 +173,7 @@ static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
icmpv6_err_convert(type, code, &err);
seq = DCCP_SKB_CB(skb)->dccpd_seq;
seq = dccp_hdr_seq(dh);
/* Might be for an request_sock */
switch (sk->sk_state) {
struct request_sock *req, **prev;
@ -787,7 +787,7 @@ static int dccp_v6_rcv(struct sk_buff *skb)
dh = dccp_hdr(skb);
DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb);
DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
if (dccp_packet_without_ack(skb))