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xrdp_mcs.c
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xrdp_mcs.c
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/**
* xrdp: A Remote Desktop Protocol server.
*
* Copyright (C) Jay Sorg 2004-2014
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* mcs layer which implements the Multipoint Communication Service protocol as
* specified in [ITU-T T.125]
*/
#if defined(HAVE_CONFIG_H)
#include <config_ac.h>
#endif
#include "libxrdp.h"
#include "ms-rdpbcgr.h"
#include "log.h"
/* Forward references */
static int
handle_non_tls_client_channel_join_requests(struct xrdp_mcs *self,
struct stream *s, int *appid);
/*****************************************************************************/
struct xrdp_mcs *
xrdp_mcs_create(struct xrdp_sec *owner, struct trans *trans,
struct stream *client_mcs_data,
struct stream *server_mcs_data)
{
struct xrdp_mcs *self;
self = (struct xrdp_mcs *)g_malloc(sizeof(struct xrdp_mcs), 1);
self->sec_layer = owner;
self->userid = 1;
self->chanid = 1001;
self->client_mcs_data = client_mcs_data;
self->server_mcs_data = server_mcs_data;
self->iso_layer = xrdp_iso_create(self, trans);
self->channel_list = list_create();
return self;
}
/*****************************************************************************/
void
xrdp_mcs_delete(struct xrdp_mcs *self)
{
struct mcs_channel_item *channel_item;
int index;
int count;
if (self == 0)
{
return;
}
/* here we have to free the channel items and anything in them */
count = self->channel_list->count;
for (index = count - 1; index >= 0; index--)
{
channel_item = (struct mcs_channel_item *)
list_get_item(self->channel_list, index);
g_free(channel_item);
}
list_delete(self->channel_list);
xrdp_iso_delete(self->iso_layer);
/* make sure we get null pointer exception if struct is used again. */
LOG_DEVEL(LOG_LEVEL_TRACE, "xrdp_mcs_delete processed");
g_memset(self, 0, sizeof(struct xrdp_mcs)) ;
g_free(self);
}
/*****************************************************************************/
/* Send an [ITU-T T.125] DomainMCSPDU message with type ChannelJoinConfirm */
/* returns error = 1 ok = 0 */
static int
xrdp_mcs_send_cjcf(struct xrdp_mcs *self, int userid, int chanid)
{
struct stream *s;
make_stream(s);
init_stream(s, 8192);
if (xrdp_iso_init(self->iso_layer, s) != 0)
{
free_stream(s);
LOG(LOG_LEVEL_ERROR, "xrdp_mcs_send_cjcf: xrdp_iso_init failed");
return 1;
}
/* The DomainMCSPDU choice index is a 6-bit int with the next bit as the
bit field of the two optional fields in the struct (channelId, nonStandard)
*/
out_uint8(s, (MCS_CJCF << 2) | 0x02); /* DomainMCSPDU choice index,
channelId field is present,
nonStandard field is not present */
out_uint8(s, 0); /* result choice index 0 = rt-successful */
out_uint16_be(s, userid); /* initiator */
out_uint16_be(s, chanid); /* requested */
out_uint16_be(s, chanid); /* channelId (OPTIONAL) */
s_mark_end(s);
LOG_DEVEL(LOG_LEVEL_TRACE, "Sending [ITU-T T.125] ChannelJoinConfirm "
"result SUCCESS, initiator %d, requested %d, "
"channelId %d", userid, chanid, chanid);
if (xrdp_iso_send(self->iso_layer, s) != 0)
{
free_stream(s);
LOG(LOG_LEVEL_ERROR, "Sening [ITU-T T.125] ChannelJoinConfirm failed");
return 1;
}
free_stream(s);
return 0;
}
/*****************************************************************************/
/* Reads the header of a DomainMCSPDU and gets the appid
*
* @return 0 for success */
static int
get_domain_mcs_pdu_header(struct xrdp_mcs *self, struct stream *s, int *appid)
{
int opcode;
if (xrdp_iso_recv(self->iso_layer, s) != 0)
{
LOG(LOG_LEVEL_ERROR, "xrdp_mcs_recv: xrdp_iso_recv failed");
return 1;
}
if (!s_check_rem_and_log(s, 1, "Parsing [ITU-T T.125] DomainMCSPDU"))
{
return 1;
}
/* The DomainMCSPDU choice index is a 6-bit int with the 2 least
significant bits of the byte as padding */
in_uint8(s, opcode);
*appid = opcode >> 2; /* 2-bit padding */
LOG_DEVEL(LOG_LEVEL_TRACE,
"Received [ITU-T T.125] DomainMCSPDU choice index %d", *appid);
return 0;
}
/*****************************************************************************/
/*
* Processes an [ITU-T T.125] DomainMCSPDU message.
*
* Note: DomainMCSPDU messages use the ALIGNED BASIC-PER (Packed Encoding Rules)
* from [ITU-T X.691].
*
* returns error
*/
int
xrdp_mcs_recv(struct xrdp_mcs *self, struct stream *s, int *chan)
{
int appid;
int len;
if (get_domain_mcs_pdu_header(self, s, &appid) != 0)
{
return 1;
}
if (self->expecting_channel_join_requests)
{
if (handle_non_tls_client_channel_join_requests(self, s, &appid) != 0)
{
return 1;
}
LOG(LOG_LEVEL_DEBUG, "[MCS Connection Sequence] completed");
self->expecting_channel_join_requests = 0;
}
if (appid == MCS_DPUM) /* Disconnect Provider Ultimatum */
{
LOG_DEVEL(LOG_LEVEL_TRACE,
"Received [ITU-T T.125] DisconnectProviderUltimatum");
LOG(LOG_LEVEL_DEBUG, "Received disconnection request");
return 1;
}
if (appid != MCS_SDRQ)
{
LOG(LOG_LEVEL_ERROR, "Received [ITU-T T.125] DomainMCSPDU "
"choice index %d is unknown. Expected the DomainMCSPDU to "
"contain the type SendDataRequest with index %d",
appid, MCS_SDRQ);
return 1;
}
if (!s_check_rem_and_log(s, 6, "Parsing [ITU-T T.125] SendDataRequest"))
{
return 1;
}
in_uint8s(s, 2); /* initiator */
in_uint16_be(s, *chan); /* channelId */
in_uint8s(s, 1); /* dataPriority (4-bits), segmentation (2-bits), padding (2-bits) */
in_uint8(s, len); /* userData Length (byte 1) */
if ((len & 0xC0) == 0x80)
{
/* From [ITU-T X.691] 11.9.3.7
encoding a length determinant if "n" is greater than 127 and
less than 16K, then n is encoded using 2 bytes.
The first byte will have the two highest order bits set to 1 and 0
(ie. len & 0xC0 == 0x80) and the length is encoded as remaining 14 bits of
the two bytes (ie. len & 0x3fff). */
if (!s_check_rem_and_log(s, 1, "Parsing [ITU-T T.125] SendDataRequest userData Length"))
{
return 1;
}
in_uint8s(s, 1); /* userData Length (byte 2) */
}
else if ((len & 0xC0) == 0xC0)
{
/* From [ITU-T X.691] 11.9.3.8
encoding a length determinant if "n" is greater than 16K,
then the list of items is fragmented with the length of the first
fragment encoded using 1 byte. The two highest order bits are set
to 1 and 1 (ie. len & 0xC0 == 0xC0) and the remaining 6 bits contain
a multiplyer for 16K (ie. n = (len & 0x3f) * 0x3f)
*/
LOG(LOG_LEVEL_ERROR, "[ITU-T T.125] SendDataRequest with length greater "
"than 16K is not supported. len 0x%2.2x", len);
return 1;
}
LOG_DEVEL(LOG_LEVEL_TRACE, "Received [ITU-T T.125] SendDataRequest "
"initiator (ignored), channelId %d, dataPriority (ignored), "
"segmentation (ignored), userData Length (ignored)", *chan);
return 0;
}
/*****************************************************************************/
/**
* Parse the identifier and length of a [ITU-T X.690] BER (Basic Encoding Rules)
* structure header.
*
* @param self
* @param s [in] - the stream to read from
* @param tag_val [in] - the expected tag value
* @param len [out] - the length of the structure
* @returns error
*/
static int
xrdp_mcs_ber_parse_header(struct xrdp_mcs *self, struct stream *s,
int tag_val, int *len)
{
int tag;
int l;
int i;
if (tag_val > 0xff)
{
if (!s_check_rem_and_log(s, 2, "Parsing [ITU-T X.690] Identifier"))
{
return 1;
}
in_uint16_be(s, tag);
}
else
{
if (!s_check_rem_and_log(s, 1, "Parsing [ITU-T X.690] Identifier"))
{
return 1;
}
in_uint8(s, tag);
}
if (tag != tag_val)
{
LOG(LOG_LEVEL_ERROR, "Parsed [ITU-T X.690] Identifier: "
"expected 0x%4.4x, actual 0x%4.4x", tag_val, tag);
return 1;
}
if (!s_check_rem_and_log(s, 1, "Parsing [ITU-T X.690] Length"))
{
return 1;
}
in_uint8(s, l);
if (l & 0x80)
{
l = l & ~0x80;
*len = 0;
while (l > 0)
{
if (!s_check_rem_and_log(s, 1, "Parsing [ITU-T X.690] Length"))
{
return 1;
}
in_uint8(s, i);
*len = (*len << 8) | i;
l--;
}
}
else
{
*len = l;
}
LOG_DEVEL(LOG_LEVEL_TRACE, "Parsed BER header [ITU-T X.690] "
"Identifier 0x%4.4x, Length %d", tag, *len);
return 0;
}
/*****************************************************************************/
/* Parses a [ITU-T T.125] DomainParameters structure encoded using BER */
/* returns error */
static int
xrdp_mcs_parse_domain_params(struct xrdp_mcs *self, struct stream *s)
{
int len;
if (xrdp_mcs_ber_parse_header(self, s, MCS_TAG_DOMAIN_PARAMS, &len) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] DomainParameters failed");
return 1;
}
if (len < 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] DomainParameters length field is "
"invalid. Expected >= 0, actual %d", len);
return 1;
}
if (!s_check_rem_and_log(s, len, "Parsing [ITU-T T.125] DomainParameters"))
{
return 1;
}
in_uint8s(s, len); /* skip all fields */
return !s_check_rem_and_log(s, 0, "Parsing [ITU-T T.125] DomainParameters");
}
/*****************************************************************************/
/* Process a [ITU-T T.125] Connect-Initial message encoded using BER */
/* returns error */
static int
xrdp_mcs_recv_connect_initial(struct xrdp_mcs *self)
{
int len;
struct stream *s;
s = libxrdp_force_read(self->iso_layer->trans);
if (s == 0)
{
LOG(LOG_LEVEL_ERROR, "Processing [ITU-T T.125] Connect-Initial failed");
return 1;
}
if (xrdp_iso_recv(self->iso_layer, s) != 0)
{
LOG(LOG_LEVEL_ERROR, "Processing [ITU-T T.125] Connect-Initial failed");
return 1;
}
if (xrdp_mcs_ber_parse_header(self, s, MCS_CONNECT_INITIAL, &len) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial failed");
return 1;
}
if (xrdp_mcs_ber_parse_header(self, s, BER_TAG_OCTET_STRING, &len) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial callingDomainSelector failed");
return 1;
}
if (len < 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial callingDomainSelector length field is "
"invalid. Expected >= 0, actual %d", len);
return 1;
}
if (!s_check_rem_and_log(s, len, "Parsing [ITU-T T.125] Connect-Initial callingDomainSelector"))
{
return 1;
}
in_uint8s(s, len); /* [ITU-T T.125] Connect-Initial callingDomainSelector */
if (xrdp_mcs_ber_parse_header(self, s, BER_TAG_OCTET_STRING, &len) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial calledDomainSelector failed");
return 1;
}
if (len < 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial calledDomainSelector length field is "
"invalid. Expected >= 0, actual %d", len);
return 1;
}
if (!s_check_rem_and_log(s, len, "Parsing [ITU-T T.125] Connect-Initial calledDomainSelector"))
{
return 1;
}
in_uint8s(s, len); /* [ITU-T T.125] Connect-Initial calledDomainSelector */
if (xrdp_mcs_ber_parse_header(self, s, BER_TAG_BOOLEAN, &len) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial upwardFlag failed");
return 1;
}
if (len < 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial upwardFlag length field is "
"invalid. Expected >= 0, actual %d", len);
return 1;
}
if (!s_check_rem_and_log(s, len, "Parsing [ITU-T T.125] Connect-Initial upwardFlag"))
{
return 1;
}
in_uint8s(s, len); /* [ITU-T T.125] Connect-Initial upwardFlag */
/* [ITU-T T.125] Connect-Initial targetParameters */
if (xrdp_mcs_parse_domain_params(self, s) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial targetParameters failed");
return 1;
}
/* [ITU-T T.125] Connect-Initial minimumParameters */
if (xrdp_mcs_parse_domain_params(self, s) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial minimumParameters failed");
return 1;
}
/* [ITU-T T.125] Connect-Initial maximumParameters */
if (xrdp_mcs_parse_domain_params(self, s) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial maximumParameters failed");
return 1;
}
if (xrdp_mcs_ber_parse_header(self, s, BER_TAG_OCTET_STRING, &len) != 0)
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial userData failed");
return 1;
}
/* mcs userData can not be zero length */
if ((len <= 0) || (len > 16 * 1024))
{
LOG(LOG_LEVEL_ERROR,
"Parsing [ITU-T T.125] Connect-Initial userData: invalid length. "
"Expected min 1, max %d; Actual %d", 16 * 1024, len);
return 1;
}
if (!s_check_rem_and_log(s, len, "Parsing [ITU-T T.125] Connect-Initial userData"))
{
return 1;
}
LOG_DEVEL(LOG_LEVEL_TRACE, "Received header [ITU-T T.125] Connect-Initial "
"callingDomainSelector (ignored), calledDomainSelector (ignored), "
"upwardFlag (ignored), targetParameters (ignored), "
"minimumParameters (ignored), maximumParameters (ignored), "
"userData (copied to client_mcs_data)");
/* make a copy of client mcs data */
init_stream(self->client_mcs_data, len);
out_uint8a(self->client_mcs_data, s->p, len); /* [ITU-T T.125] Connect-Initial userData */
in_uint8s(s, len);
s_mark_end(self->client_mcs_data);
if (!s_check_end_and_log(s, "MCS protocol error [ITU-T T.125] Connect-Initial"))
{
return 1;
}
return 0;
}
/*****************************************************************************/
/* Processes a [ITU-T T.25] DomainMCSPDU with type ErectDomainRequest
*
* Note: a parsing example can be found in [MS-RDPBCGR] 4.1.5
*
* returns error */
static int
xrdp_mcs_recv_edrq(struct xrdp_mcs *self)
{
int opcode;
struct stream *s;
s = libxrdp_force_read(self->iso_layer->trans);
if (s == 0)
{
LOG(LOG_LEVEL_ERROR, "Processing [ITU-T T.125] ErectDomainRequest failed");
return 1;
}
if (xrdp_iso_recv(self->iso_layer, s) != 0)
{
LOG(LOG_LEVEL_ERROR, "Processing [ITU-T T.125] ErectDomainRequest failed");
return 1;
}
if (!s_check_rem_and_log(s, 1, "Parsing [ITU-T T.125] DomainMCSPDU"))
{
return 1;
}
/* The DomainMCSPDU choice index is a 6-bit int with the next bit as the
bit field of the optional field in the struct
*/
in_uint8(s, opcode);
if ((opcode >> 2) != MCS_EDRQ)
{
LOG(LOG_LEVEL_ERROR, "Parsed [ITU-T T.125] DomainMCSPDU choice index "
"expected %d, received %d", MCS_EDRQ, (opcode >> 2));
return 1;
}
if (!s_check_rem_and_log(s, 4, "Parsing [ITU-T T.125] ErectDomainRequest"))
{
return 1;
}
in_uint8s(s, 2); /* subHeight */
in_uint8s(s, 2); /* subInterval */
LOG_DEVEL(LOG_LEVEL_TRACE, "Received [ITU-T T.125] DomainMCSPDU "
"choice index %d (ErectDomainRequest)", (opcode >> 2));
LOG_DEVEL(LOG_LEVEL_TRACE, "Received [ITU-T T.125] ErectDomainRequest "
"subHeight (ignored), subInterval (ignored), "
"nonStandard (%s)",
(opcode & 2) ? "present" : "not present");
/*
* [MS-RDPBCGR] 2.2.1.5 says that the mcsEDrq field is 5 bytes (which have
* already been read into the opcode and previous fields), so the
* nonStandard field should never be present.
*/
if (opcode & 2) /* ErectDomainRequest v3 nonStandard optional field is present? */
{
if (!s_check_rem_and_log(s, 2, "Parsing [ITU-T T.125] ErectDomainRequest nonStandard"))
{
return 1;
}
in_uint16_be(s, self->userid); /* NonStandardParameter.key
NonStandardParameter.data */
LOG_DEVEL(LOG_LEVEL_TRACE, "Received [ITU-T T.125] DomainMCSPDU "
"choice index %d (ErectDomainRequest)", (opcode >> 2));
}
if (!s_check_end_and_log(s, "MCS protocol error [ITU-T T.125] ErectDomainRequest"))
{
return 1;
}
return 0;
}
/*****************************************************************************/
/* Processes a [ITU-T T.25] DomainMCSPDU with type AttachUserRequest
*
* Note: a parsing example can be found in [MS-RDPBCGR] 4.1.6
*
* returns error */
static int
xrdp_mcs_recv_aurq(struct xrdp_mcs *self)
{
int opcode;
struct stream *s;
s = libxrdp_force_read(self->iso_layer->trans);
if (s == 0)
{
LOG(LOG_LEVEL_ERROR, "Processing [ITU-T T.125] AttachUserRequest failed");
return 1;
}
if (xrdp_iso_recv(self->iso_layer, s) != 0)
{
LOG(LOG_LEVEL_ERROR, "Processing [ITU-T T.125] AttachUserRequest failed");
return 1;
}
if (!s_check_rem_and_log(s, 1, "Parsing [ITU-T T.125] DomainMCSPDU"))
{
return 1;
}
/* The DomainMCSPDU choice index is a 6-bit int with the next bit as the
bit field of the optional field in the struct
*/
in_uint8(s, opcode);
if ((opcode >> 2) != MCS_AURQ)
{
LOG(LOG_LEVEL_ERROR, "Parsed [ITU-T T.125] DomainMCSPDU choice index "
"expected %d, received %d", MCS_AURQ, (opcode >> 2));
return 1;
}
/*
* [MS-RDPBCGR] 2.2.1.6 says that the mcsAUrq field is 1 bytes (which have
* already been read into the opcode), so the nonStandard field should
* never be present.
*/
if (opcode & 2)
{
if (!s_check_rem_and_log(s, 2, "Parsing [ITU-T T.125] AttachUserRequest nonStandard"))
{
return 1;
}
in_uint16_be(s, self->userid); /* NonStandardParameter.key
NonStandardParameter.data */
}
LOG_DEVEL(LOG_LEVEL_TRACE, "Received [ITU-T T.125] DomainMCSPDU "
"choice index %d (AttachUserRequest)", (opcode >> 2));
LOG_DEVEL(LOG_LEVEL_TRACE, "Received [ITU-T T.125] AttachUserRequest "
"nonStandard (%s)",
(opcode & 2) ? "present" : "not present");
if (!s_check_end_and_log(s, "MCS protocol error [ITU-T T.125] AttachUserRequest"))
{
return 1;
}
return 0;
}
/*****************************************************************************/
/* Send a [ITU-T T.125] DomainMCSPDU with type AttachUserConfirm.
*
* Note: a parsing example can be found in [MS-RDPBCGR] 4.1.7
*
* returns error */
static int
xrdp_mcs_send_aucf(struct xrdp_mcs *self)
{
struct stream *s;
make_stream(s);
init_stream(s, 8192);
if (xrdp_iso_init(self->iso_layer, s) != 0)
{
free_stream(s);
LOG(LOG_LEVEL_ERROR, "xrdp_mcs_send_aucf: xrdp_iso_init failed");
return 1;
}
out_uint8(s, ((MCS_AUCF << 2) | 2)); /* AttachUserConfirm
optional field initiator is present */
out_uint8s(s, 1); /* result = 0 rt-successful */
out_uint16_be(s, self->userid); /* initiator */
s_mark_end(s);
LOG_DEVEL(LOG_LEVEL_TRACE, "Sending [ITU-T T.125] DomainMCSPDU "
"of type AttachUserConfirm: result SUCCESS, initiator %d",
self->userid);
if (xrdp_iso_send(self->iso_layer, s) != 0)
{
free_stream(s);
LOG(LOG_LEVEL_ERROR, "Sending [ITU-T T.125] AttachUserConfirm failed");
return 1;
}
free_stream(s);
return 0;
}
/*****************************************************************************/
/* Processes a [ITU-T T.25] DomainMCSPDU with type ChannelJoinRequest
*
* Note: a parsing example can be found in [MS-RDPBCGR] 4.1.8.1.1
*
* returns error */
static int
xrdp_mcs_recv_cjrq(struct xrdp_mcs *self, int *channel_id)
{
int opcode;
struct stream *s;
int initiator;
s = libxrdp_force_read(self->iso_layer->trans);
if (s == 0)
{
LOG(LOG_LEVEL_ERROR, "Processing [ITU-T T.25] ChannelJoinRequest failed");
return 1;
}
if (xrdp_iso_recv(self->iso_layer, s) != 0)
{
LOG(LOG_LEVEL_ERROR, "Processing [ITU-T T.25] ChannelJoinRequest failed");
return 1;
}
if (!s_check_rem_and_log(s, 1, "Parsing [ITU-T T.125] DomainMCSPDU"))
{
return 1;
}
in_uint8(s, opcode);
LOG_DEVEL(LOG_LEVEL_TRACE, "Received [ITU-T T.125] DomainMCSPDU "
"choice index %d (ChannelJoinRequest)", (opcode >> 2));
if ((opcode >> 2) != MCS_CJRQ)
{
LOG(LOG_LEVEL_ERROR, "Parsed [ITU-T T.125] DomainMCSPDU choice index "
"expected %d, received %d", MCS_CJRQ, (opcode >> 2));
return 1;
}
if (!s_check_rem_and_log(s, 4, "Parsing [ITU-T T.125] ChannelJoinRequest"))
{
return 1;
}
in_uint16_be(s, initiator);
in_uint16_be(s, *channel_id);
/*
* [MS-RDPBCGR] 2.2.1.8 says that the mcsAUrq field is 5 bytes (which have
* already been read into the opcode and other fields), so the nonStandard
* field should never be present.
*/
if (opcode & 2)
{
if (!s_check_rem_and_log(s, 2, "Parsing [ITU-T T.125] ChannelJoinRequest nonStandard"))
{
return 1;
}
in_uint8s(s, 2); /* NonStandardParameter.key
NonStandardParameter.data */
}
LOG_DEVEL(LOG_LEVEL_TRACE, "Received [ITU-T T.125] ChannelJoinRequest "
"initiator %d, channelId %d, "
"nonStandard (%s)",
initiator, *channel_id,
(opcode & 2) ? "present" : "not present");
if (!s_check_end_and_log(s, "MCS protocol error [ITU-T T.125] ChannelJoinRequest"))
{
return 1;
}
return 0;
}
/*****************************************************************************/
/* Write the identifier and length of a [ITU-T X.690] BER (Basic Encoding Rules)
* structure header.
* returns error */
static int
xrdp_mcs_ber_out_header(struct xrdp_mcs *self, struct stream *s,
int tag_val, int len)
{
if (tag_val > 0xff)
{
out_uint16_be(s, tag_val);
}
else
{
out_uint8(s, tag_val);
}
if (len >= 0x80)
{
out_uint8(s, 0x82);
out_uint16_be(s, len);
}
else
{
out_uint8(s, len);
}
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding header [ITU-T X.690] Identifier %d, Length %d",
tag_val, len);
return 0;
}
/*****************************************************************************/
/* returns error */
static int
xrdp_mcs_ber_out_int8(struct xrdp_mcs *self, struct stream *s, int value)
{
xrdp_mcs_ber_out_header(self, s, BER_TAG_INTEGER, 1);
out_uint8(s, value);
return 0;
}
#if 0 /* not used */
/*****************************************************************************/
/* returns error */
static int
xrdp_mcs_ber_out_int16(struct xrdp_mcs *self, struct stream *s, int value)
{
xrdp_mcs_ber_out_header(self, s, BER_TAG_INTEGER, 2);
out_uint8(s, (value >> 8));
out_uint8(s, value);
return 0;
}
#endif
/*****************************************************************************/
/* returns error */
static int
xrdp_mcs_ber_out_int24(struct xrdp_mcs *self, struct stream *s, int value)
{
xrdp_mcs_ber_out_header(self, s, BER_TAG_INTEGER, 3);
out_uint8(s, (value >> 16));
out_uint8(s, (value >> 8));
out_uint8(s, value);
return 0;
}
/*****************************************************************************/
/* returns error */
static int
xrdp_mcs_out_domain_params(struct xrdp_mcs *self, struct stream *s,
int max_channels,
int max_users, int max_tokens,
int max_pdu_size)
{
xrdp_mcs_ber_out_header(self, s, MCS_TAG_DOMAIN_PARAMS, 26);
xrdp_mcs_ber_out_int8(self, s, max_channels);
xrdp_mcs_ber_out_int8(self, s, max_users);
xrdp_mcs_ber_out_int8(self, s, max_tokens);
xrdp_mcs_ber_out_int8(self, s, 1); /* numPriorities */
xrdp_mcs_ber_out_int8(self, s, 0); /* minThroughput */
xrdp_mcs_ber_out_int8(self, s, 1); /* maxHeight */
xrdp_mcs_ber_out_int24(self, s, max_pdu_size);
xrdp_mcs_ber_out_int8(self, s, 2); /* protocolVersion */
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding struct [ITU-T T.125] DomainParameters "
"maxChannelIds %d, maxUserIds %d, maxTokenIds %d, numPriorities 1, "
"minThroughput 0 B/s, maxHeight 1, maxMCSPDUsize %d, "
"protocolVersion 2",
max_channels, max_users, max_tokens, max_pdu_size);
return 0;
}
/*****************************************************************************/
/* Write an [ITU-T T.124] ConnectData (ALIGNED variant of BASIC-PER) message
* with ConnectGCCPDU, ConferenceCreateResponse,
* and [MS-RDPBCGR] Server Data Blocks as user data.
*/
int
xrdp_mcs_out_gcc_data(struct xrdp_sec *self)
{
struct stream *s;
int num_channels_even;
int num_channels;
int index;
int channel;
int gcc_size;
char *gcc_size_ptr;
char *ud_ptr;
int header_length = 0;
int server_cert_len = 0;
int public_key_blob_len = 0;
int key_len = 0;
int bit_len = 0;
int data_len = 0;
int modulus_len = 0;
num_channels = self->mcs_layer->channel_list->count;
num_channels_even = num_channels + (num_channels & 1);
s = &(self->server_mcs_data);
init_stream(s, 8192);
/* [ITU-T T.124] ConnectData (ALIGNED variant of BASIC-PER) */
out_uint16_be(s, 5); /* = 0x00 0x05 */
/* t124Identifier choice index = 0 (object) */
/* object length = 5 */
out_uint16_be(s, 0x14); /* t124Identifier.object = ??? (0x00 0x14 0x7c 0x00 0x01) */
out_uint8(s, 0x7c);
out_uint16_be(s, 1); /* -- */
out_uint8(s, 0x2a); /* connectPDU length = 42 */
/* connectPDU octet string of type ConnectGCCPDU
(unknown where this octet string is defined to be
of type ConnectGCCPDU) */
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding struct [ITU-T T.124] ConnectData "
"t124Identifier.object 0x00 0x14 0x7c 0x00 0x01, connectPDU length %d",
0x2a);
/* [ITU-T T.124] ConnectGCCPDU (ALIGNED variant of BASIC-PER) */
out_uint8(s, 0x14); /* ConnectGCCPDU choice index 1 = ConferenceCreateResponse with userData present */
/* [ITU-T T.124] ConferenceCreateResponse (ALIGNED variant of BASIC-PER) */
out_uint8(s, 0x76); /* nodeID = 31219 - 1001 (PER offset for min value)
= 30218 (big-endian 0x760a) */
out_uint8(s, 0x0a);
out_uint8(s, 1); /* tag length */
out_uint8(s, 1); /* tag */
out_uint8(s, 0); /* result = 0 (success) */
out_uint16_le(s, 0xc001); /* userData set count = 1 (0x01),
userData.isPresent = 0x80 (yes) | userData.key choice index = 0x40 (1 = h221NonStandard) */
out_uint8(s, 0); /* userData.key.h221NonStandard length
= 4 - 4 (PER offset for min value) (H221NonStandardIdentifier is an octet string SIZE (4..255))
= 0
*/
/* [ITU-T H.221] H221NonStandardIdentifier uses country codes and
manufactuer codes from [ITU-T T.35]. Unknown why these values are used,
maybe this is just copied from the [MS-RDPBCGR] 4.1.4 example which uses
the value "McDn" */
out_uint8(s, 0x4d); /* M */
out_uint8(s, 0x63); /* c */
out_uint8(s, 0x44); /* D */
out_uint8(s, 0x6e); /* n */
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding struct [ITU-T T.124] ConferenceCreateResponse "
"nodeID %d, result SUCCESS", 0x760a + 1001);
/* ConferenceCreateResponse.userData.key.value (octet string) */
/* GCC Response Total Length - 2 bytes , set later */
gcc_size_ptr = s->p; /* RDPGCCUserDataResponseLength */
out_uint8s(s, 2);
ud_ptr = s->p; /* User Data */
/* [MS-RDPBCGR] TS_UD_HEADER */
out_uint16_le(s, SEC_TAG_SRV_INFO); /* type */
if (self->mcs_layer->iso_layer->rdpNegData)
{
out_uint16_le(s, 12); /* length */
}
else
{
out_uint16_le(s, 8); /* length */
}
/* [MS-RDPBCGR] TS_UD_SC_CORE */
out_uint8(s, 4); /* version (0x00080004 = rdp5, 0x00080001 = rdp4) */
out_uint8(s, 0);
out_uint8(s, 8);
out_uint8(s, 0); /* version (last byte) */
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding struct header [MS-RDPBCGR] TS_UD_HEADER "
"type 0x%4.4x, length %d",
SEC_TAG_SRV_INFO,
self->mcs_layer->iso_layer->rdpNegData ? 12 : 8);
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding struct [MS-RDPBCGR] TS_UD_SC_CORE "
"<Required fields> version 0x%8.8x", 0x00080004);
if (self->mcs_layer->iso_layer->rdpNegData)
{
/* RequestedProtocol */
out_uint32_le(s, self->mcs_layer->iso_layer->requestedProtocol); /* clientRequestedProtocols */
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding struct [MS-RDPBCGR] TS_UD_SC_CORE "
"<Optional fields> clientRequestedProtocols 0x%8.8x",
self->mcs_layer->iso_layer->requestedProtocol);
}
/* [MS-RDPBCGR] TS_UD_HEADER */
out_uint16_le(s, SEC_TAG_SRV_CHANNELS); /* type */
out_uint16_le(s, 8 + (num_channels_even * 2)); /* length */
/* [MS-RDPBCGR] TS_UD_SC_NET */
out_uint16_le(s, MCS_GLOBAL_CHANNEL); /* 1003, 0x03eb main channel (MCSChannelId) */
out_uint16_le(s, num_channels); /* number of other channels (channelCount) */
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding struct header [MS-RDPBCGR] TS_UD_HEADER "
"type 0x%4.4x, length %d",
SEC_TAG_SRV_CHANNELS, 8 + (num_channels_even * 2));
LOG_DEVEL(LOG_LEVEL_TRACE, "Adding struct [MS-RDPBCGR] TS_UD_SC_NET "
"MCSChannelId %d, channelCount %d",
MCS_GLOBAL_CHANNEL, num_channels);
for (index = 0; index < num_channels_even; index++)
{
if (index < num_channels)
{