kekePower/rdesktop
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Refactoring of slow and fastpath handling

Browse Source 
This changes clarifies a chunk of code related to receiving
data and handle slow and fast path pdus.
This commit is contained in:
Henrik Andersson 2018-01-26 12:17:59 +01:00
parent 81c030a887
commit b5708cf775
6 changed files with 71 additions and 51 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
constants.h
View File

@ -2,6 +2,7 @@
rdesktop: A Remote Desktop Protocol client.
Miscellaneous protocol constants
Copyright (C) Matthew Chapman 1999-2008
Copyright 2017-2018 Henrik Andersson <hean01@cendio.se> for Cendio AB
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@ -36,9 +37,6 @@
#define FASTPATH_OUTPUT_SECURE_CHECKSUM 0x1
#define FASTPATH_OUTPUT_ENCRYPTED 0x2
#define IS_FASTPATH(hdr) ((hdr & 0x03) == FASTPATH_OUTPUT_ACTION_FASTPATH)
#define IS_SLOWPATH(hdr) ((hdr) == FASTPATH_OUTPUT_ACTION_X224)
/* [MS-RDPBCGR] 2.2.9.1.2.1 */
/* adjusted for position in updateHeader */
#define FASTPATH_UPDATETYPE_ORDERS 0x0

38
iso.c
View File

@ -3,7 +3,7 @@
Protocol services - ISO layer
Copyright (C) Matthew Chapman <matthewc.unsw.edu.au> 1999-2008
Copyright 2005-2011 Peter Astrand <astrand@cendio.se> for Cendio AB
Copyright 2012-2017 Henrik Andersson <hean01@cendio.se> for Cendio AB
Copyright 2012-2018 Henrik Andersson <hean01@cendio.se> for Cendio AB
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@ -98,7 +98,7 @@ iso_send_connection_request(char *username, uint32 neg_proto)
/* Receive a message on the ISO layer, return code */
static STREAM
iso_recv_msg(uint8 * code, uint8 * rdpver)
iso_recv_msg(uint8 * code, RD_BOOL *is_fastpath, uint8 *fastpath_hdr)
{
STREAM s;
uint16 length;
@ -107,16 +107,23 @@ iso_recv_msg(uint8 * code, uint8 * rdpver)
s = tcp_recv(NULL, 4);
if (s == NULL)
return NULL;
in_uint8(s, version);
if (rdpver != NULL)
*rdpver = version;
if (IS_SLOWPATH(version))
in_uint8(s, version); /* T.123 version or Fastpath output header */
/* detect if this is a slow or fast path PDU */
*fastpath_hdr = 0x00;
*is_fastpath = False;
if (version == T123_HEADER_VERSION)
{
in_uint8s(s, 1); /* reserved */
in_uint16_be(s, length); /* length */
}
else
{
/* if version is not an expected T.123 version eg. 3, then this
stream is a fast path pdu */
*is_fastpath = True;
*fastpath_hdr = version;
in_uint8(s, length); /* length1 */
if (length & 0x80)
{
@ -125,16 +132,20 @@ iso_recv_msg(uint8 * code, uint8 * rdpver)
next_be(s, length);
}
}
if (length < 4)
{
logger(Protocol, Error, "iso_recv_msg(), bad packet header, length < 4");
return NULL;
}
s = tcp_recv(s, length - 4);
if (s == NULL)
return NULL;
if (IS_FASTPATH(version))
if (*is_fastpath == True)
return s;
in_uint8s(s, 1); /* hdrlen */
in_uint8(s, *code);
if (*code == ISO_PDU_DT)
@ -180,17 +191,18 @@ iso_send(STREAM s)
/* Receive ISO transport data packet */
STREAM
iso_recv(uint8 * rdpver)
iso_recv(RD_BOOL *is_fastpath, uint8 *fastpath_hdr)
{
STREAM s;
uint8 code = 0;
s = iso_recv_msg(&code, rdpver);
s = iso_recv_msg(&code, is_fastpath, fastpath_hdr);
if (s == NULL)
return NULL;
if (rdpver != NULL)
if (IS_FASTPATH(*rdpver))
if (*is_fastpath == True)
return s;
if (code != ISO_PDU_DT)
{
logger(Protocol, Error, "iso_recv(), expected ISO_PDU_DT, got 0x%x", code);
@ -208,6 +220,8 @@ iso_connect(char *server, char *username, char *domain, char *password,
STREAM s;
uint8 code;
uint32 neg_proto;
RD_BOOL is_fastpath;
uint8 fastpath_hdr;
g_negotiate_rdp_protocol = True;
@ -236,7 +250,7 @@ iso_connect(char *server, char *username, char *domain, char *password,
iso_send_connection_request(username, neg_proto);
s = iso_recv_msg(&code, NULL);
s = iso_recv_msg(&code, &is_fastpath, &fastpath_hdr);
if (s == NULL)
return False;

28
mcs.c
View File

@ -3,6 +3,7 @@
Protocol services - Multipoint Communications Service
Copyright (C) Matthew Chapman <matthewc.unsw.edu.au> 1999-2008
Copyright 2005-2011 Peter Astrand <astrand@cendio.se> for Cendio AB
Copyright 2018 Henrik Andersson <hean01@cendio.com> for Cendio AB
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@ -90,8 +91,12 @@ mcs_recv_connect_response(STREAM mcs_data)
uint8 result;
int length;
STREAM s;
RD_BOOL is_fastpath;
uint8 fastpath_hdr;
logger(Protocol, Debug, "%s()", __func__);
s = iso_recv(NULL);
s = iso_recv(&is_fastpath, &fastpath_hdr);
if (s == NULL)
return False;
@ -160,10 +165,14 @@ mcs_send_aurq(void)
static RD_BOOL
mcs_recv_aucf(uint16 * mcs_userid)
{
RD_BOOL is_fastpath;
uint8 fastpath_hdr;
uint8 opcode, result;
STREAM s;
logger(Protocol, Debug, "%s()", __func__);
s = iso_recv(NULL);
s = iso_recv(&is_fastpath, &fastpath_hdr);
if (s == NULL)
return False;
@ -209,10 +218,14 @@ mcs_send_cjrq(uint16 chanid)
static RD_BOOL
mcs_recv_cjcf(void)
{
RD_BOOL is_fastpath;
uint8 fastpath_hdr;
uint8 opcode, result;
STREAM s;
logger(Protocol, Debug, "%s()", __func__);
s = iso_recv(NULL);
s = iso_recv(&is_fastpath, &fastpath_hdr);
if (s == NULL)
return False;
@ -303,17 +316,18 @@ mcs_send(STREAM s)
/* Receive an MCS transport data packet */
STREAM
mcs_recv(uint16 * channel, uint8 * rdpver)
mcs_recv(uint16 * channel, RD_BOOL *is_fastpath, uint8 *fastpath_hdr)
{
uint8 opcode, appid, length;
STREAM s;
s = iso_recv(rdpver);
s = iso_recv(is_fastpath, fastpath_hdr);
if (s == NULL)
return NULL;
if (rdpver != NULL)
if (*rdpver != 3)
if (*is_fastpath == True)
return s;
in_uint8(s, opcode);
appid = opcode >> 2;
if (appid != MCS_SDIN)

6
proto.h
View File

@ -82,7 +82,7 @@ void ewmh_init(void);
/* iso.c */
STREAM iso_init(int length);
void iso_send(STREAM s);
STREAM iso_recv(uint8 * rdpver);
STREAM iso_recv(RD_BOOL *is_fastpath, uint8 *fastpath_hdr);
RD_BOOL iso_connect(char *server, char *username, char *domain, char *password, RD_BOOL reconnect,
uint32 * selected_protocol);
void iso_disconnect(void);
@ -95,7 +95,7 @@ void licence_process(STREAM s);
STREAM mcs_init(int length);
void mcs_send_to_channel(STREAM s, uint16 channel);
void mcs_send(STREAM s);
STREAM mcs_recv(uint16 * channel, uint8 * rdpver);
STREAM mcs_recv(uint16 * channel, RD_BOOL *is_fastpath, uint8 *fastpath_hdr);
RD_BOOL mcs_connect_start(char *server, char *username, char *domain, char *password,
RD_BOOL reconnect, uint32 * selected_protocol);
RD_BOOL mcs_connect_finalize(STREAM s);
@ -199,7 +199,7 @@ STREAM sec_init(uint32 flags, int maxlen);
void sec_send_to_channel(STREAM s, uint32 flags, uint16 channel);
void sec_send(STREAM s, uint32 flags);
void sec_process_mcs_data(STREAM s);
STREAM sec_recv(uint8 * rdpver);
STREAM sec_recv(RD_BOOL * is_fastpath);
RD_BOOL sec_connect(char *server, char *username, char *domain, char *password, RD_BOOL reconnect);
void sec_disconnect(void);
void sec_reset_state(void);

15
rdp.c
View File

@ -3,7 +3,7 @@
Protocol services - RDP layer
Copyright (C) Matthew Chapman <matthewc.unsw.edu.au> 1999-2008
Copyright 2003-2011 Peter Astrand <astrand@cendio.se> for Cendio AB
Copyright 2011-2017 Henrik Andersson <hean01@cendio.se> for Cendio AB
Copyright 2011-2018 Henrik Andersson <hean01@cendio.se> for Cendio AB
Copyright 2017 Karl Mikaelsson <derfian@cendio.se> for Cendio AB
This program is free software: you can redistribute it and/or modify
@ -96,22 +96,17 @@ static void rdp_out_unistr(STREAM s, char *string, int len);
static STREAM
rdp_recv(uint8 * type)
{
RD_BOOL is_fastpath;
static STREAM rdp_s;
uint16 length, pdu_type;
uint8 rdpver;
if ((rdp_s == NULL) || (g_next_packet >= rdp_s->end) || (g_next_packet == NULL))
{
rdp_s = sec_recv(&rdpver);
rdp_s = sec_recv(&is_fastpath);
if (rdp_s == NULL)
return NULL;
if (rdpver == 0xff)
{
g_next_packet = rdp_s->end;
*type = 0;
return rdp_s;
}
else if (rdpver != 3)
if (is_fastpath == True)
{
/* process_ts_fp_updates moves g_next_packet */
process_ts_fp_updates(rdp_s);

21
secure.c
View File

@ -3,7 +3,7 @@
Protocol services - RDP encryption and licensing
Copyright (C) Matthew Chapman <matthewc.unsw.edu.au> 1999-2008
Copyright 2005-2011 Peter Astrand <astrand@cendio.se> for Cendio AB
Copyright 2017 Henrik Andersson <hean01@cendio.se> for Cendio AB
Copyright 2017-2018 Henrik Andersson <hean01@cendio.se> for Cendio AB
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@ -842,26 +842,27 @@ sec_process_mcs_data(STREAM s)
/* Receive secure transport packet */
STREAM
sec_recv(uint8 * rdpver)
sec_recv(RD_BOOL *is_fastpath)
{
uint8 fastpath_hdr;
uint16 sec_flags;
uint16 channel;
STREAM s;
while ((s = mcs_recv(&channel, rdpver)) != NULL)
while ((s = mcs_recv(&channel, is_fastpath, &fastpath_hdr)) != NULL)
{
if (rdpver != NULL)
if (*is_fastpath == True)
{
if (*rdpver != 3)
{
if (*rdpver & 0x80)
/* If fastpath packet is encrypted, read data
signature and decrypt */
if (fastpath_hdr & FASTPATH_OUTPUT_ENCRYPTED)
{
in_uint8s(s, 8); /* signature */
sec_decrypt(s->p, s->end - s->p);
}
return s;
}
}
if (g_encryption || (!g_licence_issued && !g_licence_error_result))
{
/* TS_SECURITY_HEADER */
@ -926,9 +927,7 @@ sec_recv(uint8 * rdpver)
if (channel != MCS_GLOBAL_CHANNEL)
{
channel_process(s, channel);
if (rdpver != NULL)
*rdpver = 0xff;
return s;
continue;
}
return s;