diff options
author | Patrick McHardy <kaber@trash.net> | 2011-05-16 16:45:39 +0400 |
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committer | Patrick McHardy <kaber@trash.net> | 2011-05-16 16:45:39 +0400 |
commit | e6e4d9ed11fb1fab8b3256a3dc14d71b5e984ac4 (patch) | |
tree | ce2b0eb33f0be2524529d6b6d6dfe1469559d2d3 | |
parent | 274ea0e2a4cdf18110e5931b8ecbfef6353e5293 (diff) | |
download | linux-e6e4d9ed11fb1fab8b3256a3dc14d71b5e984ac4.tar.xz |
netfilter: nf_ct_sip: fix SDP parsing in TCP SIP messages for some Cisco phones
Some Cisco phones do not place the Content-Length field at the end of the
SIP message. This is valid, due to a misunderstanding of the specification
the parser expects the SDP body to start directly after the Content-Length
field. Fix the parser to scan for \r\n\r\n to locate the beginning of the
SDP body.
Reported-by: Teresa Kang <teresa_kang@gemtek.com.tw>
Signed-off-by: Patrick McHardy <kaber@trash.net>
-rw-r--r-- | net/netfilter/nf_conntrack_sip.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c index 1f81abde131f..c05c0dc33499 100644 --- a/net/netfilter/nf_conntrack_sip.c +++ b/net/netfilter/nf_conntrack_sip.c @@ -1419,6 +1419,7 @@ static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff, const char *dptr, *end; s16 diff, tdiff = 0; int ret = NF_ACCEPT; + bool term; typeof(nf_nat_sip_seq_adjust_hook) nf_nat_sip_seq_adjust; if (ctinfo != IP_CT_ESTABLISHED && @@ -1453,10 +1454,15 @@ static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff, if (dptr + matchoff == end) break; - if (end + strlen("\r\n\r\n") > dptr + datalen) - break; - if (end[0] != '\r' || end[1] != '\n' || - end[2] != '\r' || end[3] != '\n') + term = false; + for (; end + strlen("\r\n\r\n") <= dptr + datalen; end++) { + if (end[0] == '\r' && end[1] == '\n' && + end[2] == '\r' && end[3] == '\n') { + term = true; + break; + } + } + if (!term) break; end += strlen("\r\n\r\n") + clen; |