diff options
Diffstat (limited to 'epan/dissectors/asn1/ranap')
| -rw-r--r-- | epan/dissectors/asn1/ranap/packet-ranap-template.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/epan/dissectors/asn1/ranap/packet-ranap-template.c b/epan/dissectors/asn1/ranap/packet-ranap-template.c index 6dcc0b92de..ef7c2d7de0 100644 --- a/epan/dissectors/asn1/ranap/packet-ranap-template.c +++ b/epan/dissectors/asn1/ranap/packet-ranap-template.c @@ -267,12 +267,9 @@ dissect_sccp_ranap_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, voi { guint8 temp; guint16 word; - asn1_ctx_t asn1_ctx; guint length; int offset; - asn1_ctx_init(&asn1_ctx, ASN1_ENC_PER, TRUE, pinfo); - /* Is it a ranap packet? * * 4th octet should be the length of the rest of the message. @@ -285,9 +282,21 @@ dissect_sccp_ranap_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, voi #define LENGTH_OFFSET 3 #define MSG_TYPE_OFFSET 1 if (tvb_captured_length(tvb) < RANAP_MSG_MIN_LENGTH) { return FALSE; } - /* Read the length NOTE offset in bits */ - offset = dissect_per_length_determinant(tvb, LENGTH_OFFSET<<3, &asn1_ctx, tree, -1, &length, NULL); - offset = offset>>3; + /* compute aligned PER length determinant without calling dissect_per_length_determinant() + to avoid exceptions and info added to tree, info column and expert info */ + offset = LENGTH_OFFSET; + length = tvb_get_guint8(tvb, offset); + offset += 1; + if ((length & 0x80) == 0x80) { + if ((length & 0xc0) == 0x80) { + length &= 0x3f; + length <<= 8; + length += tvb_get_guint8(tvb, offset); + offset += 1; + } else { + length = 0; + } + } if (length!= (tvb_reported_length(tvb) - offset)){ return FALSE; } |