/* returns TRUE if this TCP segment carries a MPA FPDU and FALSE otherwise */
static gboolean
is_mpa_fpdu(packet_info *pinfo)
{
conversation_t *conversation = NULL;
mpa_state_t *state = NULL;
conversation = find_conversation(pinfo->fd->num, &pinfo->src,
&pinfo->dst, pinfo->ptype, pinfo->srcport,
pinfo->destport, 0);
if (!conversation) {
return FALSE;
}
state = get_mpa_state(conversation);
if (!state) {
return FALSE;
}
/* make sure all MPA connection parameters have been set */
if (!state->full_operation) {
return FALSE;
}
if (pinfo->fd->num == state->req_frame_num
|| pinfo->fd->num == state->rep_frame_num) {
return FALSE;
} else {
return TRUE;
}
}
/* returns TRUE if this TCP segment carries a MPA REQUEST and FLASE otherwise */
static gboolean
is_mpa_req(tvbuff_t *tvb, packet_info *pinfo)
{
conversation_t *conversation = NULL;
mpa_state_t *state = NULL;
guint8 mcrres;
if (tvb_get_ntoh64(tvb, 0) != MPA_REQ_REP_FRAME
|| tvb_get_ntoh64(tvb, 8) != MPA_ID_REQ_FRAME)
return FALSE;
conversation = find_conversation(pinfo->fd->num, &pinfo->src,
&pinfo->dst, pinfo->ptype, pinfo->srcport,
pinfo->destport, 0);
if (!conversation) {
conversation = conversation_new(pinfo->fd->num, &pinfo->src,
&pinfo->dst, pinfo->ptype, pinfo->srcport,
pinfo->destport, 0);
}
if (!get_mpa_state(conversation)) {
/* associate a MPA connection state to this conversation if
* there is no MPA state already associated to this connection
*/
state = init_mpa_state();
/* anaylize MPA connection parameter and record them */
mcrres = tvb_get_guint8(tvb, 16);
state->ini_exp_m_res = mcrres & MPA_MARKER_FLAG;
state->crc = mcrres & MPA_CRC_FLAG;
state->revision = tvb_get_guint8(tvb, 17);
state->req_frame_num = pinfo->fd->num;
state->minfo[MPA_INITIATOR].port = pinfo->srcport;
state->minfo[MPA_RESPONDER].port = pinfo->destport;
conversation_add_proto_data(conversation, proto_iwarp_mpa, state);
/* update expert info */
if (mcrres & MPA_RESERVED_FLAG)
expert_add_info_format(pinfo, NULL, PI_REQUEST_CODE, PI_WARN,
"Res field is NOT set to zero as required by RFC 5044");
if (state->revision != 1)
expert_add_info_format(pinfo, NULL, PI_REQUEST_CODE, PI_WARN,
"Rev field is NOT set to one as required by RFC 5044");
}
return TRUE;
}
/* returns TRUE if this TCP segment carries a MPA REPLY and FALSE otherwise */
static gboolean
is_mpa_rep(tvbuff_t *tvb, packet_info *pinfo)
{
conversation_t *conversation = NULL;
mpa_state_t *state = NULL;
guint8 mcrres;
if (tvb_get_ntoh64(tvb, 0) != MPA_REQ_REP_FRAME
|| tvb_get_ntoh64(tvb, 8) != MPA_ID_REP_FRAME) {
return FALSE;
}
conversation = find_conversation(pinfo->fd->num, &pinfo->src,
&pinfo->dst, pinfo->ptype, pinfo->srcport,
pinfo->destport, 0);
if (!conversation) {
return FALSE;
}
state = get_mpa_state(conversation);
if (!state) {
return FALSE;
}
if (!state->full_operation) {
/* update state of this conversation */
mcrres = tvb_get_guint8(tvb, 16);
state->res_exp_m_ini = mcrres & MPA_MARKER_FLAG;
state->crc = state->crc | (mcrres & MPA_CRC_FLAG);
state->rep_frame_num = pinfo->fd->num;
/* enter Full Operation Phase only if the Reject bit is not set */
if (!(mcrres & MPA_REJECT_FLAG))
state->full_operation = TRUE;
else
expert_add_info_format(pinfo, NULL, PI_RESPONSE_CODE, PI_NOTE,
"Reject bit set by Responder");
}
return TRUE;
}
/* returns TRUE if this TCP segment carries a MPA REQUEST and FLASE otherwise */
static gboolean
is_mpa_req(tvbuff_t *tvb, packet_info *pinfo)
{
conversation_t *conversation = NULL;
mpa_state_t *state = NULL;
guint8 mcrres;
if (tvb_get_ntoh64(tvb, 0) != MPA_REQ_REP_FRAME
|| tvb_get_ntoh64(tvb, 8) != MPA_ID_REQ_FRAME)
return FALSE;
conversation = find_or_create_conversation(pinfo);
if (!get_mpa_state(conversation)) {
/* associate a MPA connection state to this conversation if
* there is no MPA state already associated to this connection
*/
state = init_mpa_state();
/* anaylize MPA connection parameter and record them */
mcrres = tvb_get_guint8(tvb, 16);
state->ini_exp_m_res = mcrres & MPA_MARKER_FLAG;
state->crc = mcrres & MPA_CRC_FLAG;
state->revision = tvb_get_guint8(tvb, 17);
state->req_frame_num = pinfo->fd->num;
state->minfo[MPA_INITIATOR].port = pinfo->srcport;
state->minfo[MPA_RESPONDER].port = pinfo->destport;
conversation_add_proto_data(conversation, proto_iwarp_mpa, state);
/* update expert info */
if (mcrres & MPA_RESERVED_FLAG)
expert_add_info(pinfo, NULL, &ei_mpa_res_field_not_set0);
if (state->revision != 1)
expert_add_info(pinfo, NULL, &ei_mpa_rev_field_not_set1);
}
return TRUE;
}
/*
* Main dissection routine.
*/
static gboolean
dissect_iwarp_mpa(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
{
tvbuff_t *next_tvb = NULL;
conversation_t *conversation = NULL;
mpa_state_t *state = NULL;
struct tcpinfo *tcpinfo;
guint8 endpoint = 3;
guint16 ulpdu_length = 0;
if (data == NULL)
return FALSE;
tcpinfo = (struct tcpinfo *)data;
/* FPDU */
if (tvb_length(tvb) >= MPA_SMALLEST_FPDU_LEN && is_mpa_fpdu(pinfo)) {
conversation = find_conversation(pinfo->fd->num, &pinfo->src,
&pinfo->dst, pinfo->ptype, pinfo->srcport, pinfo->destport, 0);
state = get_mpa_state(conversation);
if (pinfo->srcport == state->minfo[MPA_INITIATOR].port) {
endpoint = MPA_INITIATOR;
} else if (pinfo->srcport == state->minfo[MPA_RESPONDER].port) {
endpoint = MPA_RESPONDER;
} else {
REPORT_DISSECTOR_BUG("endpoint cannot be determined");
}
/* Markers are used by either the Initiator or the Responder or both. */
if ((state->ini_exp_m_res || state->res_exp_m_ini) && endpoint <= MPA_RESPONDER) {
/* find the TCP sequence number of the first FPDU */
if (!state->minfo[endpoint].valid) {
state->minfo[endpoint].seq = tcpinfo->seq;
state->minfo[endpoint].valid = TRUE;
}
}
/* dissect FPDU */
ulpdu_length = dissect_mpa_fpdu(tvb, pinfo, tree, state, tcpinfo,
endpoint);
/* an ulpdu_length of 0 should never happen */
if (!ulpdu_length)
return FALSE;
/* removes Markers if any and prepares new tvbuff for next dissector */
if (endpoint <= MPA_RESPONDER && state->minfo[endpoint].valid
&& number_of_markers(state, tcpinfo, endpoint) > 0) {
next_tvb = tvb_new_subset_length(remove_markers(tvb, pinfo,
get_first_marker_offset(state, tcpinfo, endpoint),
number_of_markers(state, tcpinfo, endpoint),
fpdu_total_length(tcpinfo)), MPA_ULPDU_LENGTH_LEN,
ulpdu_length);
} else {
next_tvb = tvb_new_subset_length(tvb, MPA_ULPDU_LENGTH_LEN, ulpdu_length);
}
/* call subdissector */
if (ddp_rdmap_handle) {
call_dissector(ddp_rdmap_handle, next_tvb, pinfo, tree);
} else {
REPORT_DISSECTOR_BUG("ddp_handle was null");
}
return TRUE;
}
/* MPA REQUEST or MPA REPLY */
if (tvb_length(tvb) >= MPA_REQ_REP_FRAME_HEADER_LEN) {
if (is_mpa_req(tvb, pinfo))
return dissect_mpa_req_rep(tvb, pinfo, tree, MPA_REQUEST_FRAME);
else if (is_mpa_rep(tvb, pinfo))
return dissect_mpa_req_rep(tvb, pinfo, tree, MPA_REPLY_FRAME);
}
return FALSE;
}
