xrdp/libxrdp/xrdp_sec.c
2007-01-25 05:35:52 +00:00

1006 lines
29 KiB
C

/*
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
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
xrdp: A Remote Desktop Protocol server.
Copyright (C) Jay Sorg 2004-2007
secure layer
*/
#include "libxrdp.h"
static char g_pad_54[40] =
{ 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54,
54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54, 54,
54, 54, 54, 54, 54, 54, 54, 54 };
static char g_pad_92[48] =
{ 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92,
92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92,
92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92, 92 };
static char g_lic1[322] =
{ 0x80, 0x00, 0x3e, 0x01, 0x01, 0x02, 0x3e, 0x01,
0x7b, 0x3c, 0x31, 0xa6, 0xae, 0xe8, 0x74, 0xf6,
0xb4, 0xa5, 0x03, 0x90, 0xe7, 0xc2, 0xc7, 0x39,
0xba, 0x53, 0x1c, 0x30, 0x54, 0x6e, 0x90, 0x05,
0xd0, 0x05, 0xce, 0x44, 0x18, 0x91, 0x83, 0x81,
0x00, 0x00, 0x04, 0x00, 0x2c, 0x00, 0x00, 0x00,
0x4d, 0x00, 0x69, 0x00, 0x63, 0x00, 0x72, 0x00,
0x6f, 0x00, 0x73, 0x00, 0x6f, 0x00, 0x66, 0x00,
0x74, 0x00, 0x20, 0x00, 0x43, 0x00, 0x6f, 0x00,
0x72, 0x00, 0x70, 0x00, 0x6f, 0x00, 0x72, 0x00,
0x61, 0x00, 0x74, 0x00, 0x69, 0x00, 0x6f, 0x00,
0x6e, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00,
0x32, 0x00, 0x33, 0x00, 0x36, 0x00, 0x00, 0x00,
0x0d, 0x00, 0x04, 0x00, 0x01, 0x00, 0x00, 0x00,
0x03, 0x00, 0xb8, 0x00, 0x01, 0x00, 0x00, 0x00,
0x01, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00,
0x06, 0x00, 0x5c, 0x00, 0x52, 0x53, 0x41, 0x31,
0x48, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00,
0x3f, 0x00, 0x00, 0x00, 0x01, 0x00, 0x01, 0x00,
0x01, 0xc7, 0xc9, 0xf7, 0x8e, 0x5a, 0x38, 0xe4,
0x29, 0xc3, 0x00, 0x95, 0x2d, 0xdd, 0x4c, 0x3e,
0x50, 0x45, 0x0b, 0x0d, 0x9e, 0x2a, 0x5d, 0x18,
0x63, 0x64, 0xc4, 0x2c, 0xf7, 0x8f, 0x29, 0xd5,
0x3f, 0xc5, 0x35, 0x22, 0x34, 0xff, 0xad, 0x3a,
0xe6, 0xe3, 0x95, 0x06, 0xae, 0x55, 0x82, 0xe3,
0xc8, 0xc7, 0xb4, 0xa8, 0x47, 0xc8, 0x50, 0x71,
0x74, 0x29, 0x53, 0x89, 0x6d, 0x9c, 0xed, 0x70,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x08, 0x00, 0x48, 0x00, 0xa8, 0xf4, 0x31, 0xb9,
0xab, 0x4b, 0xe6, 0xb4, 0xf4, 0x39, 0x89, 0xd6,
0xb1, 0xda, 0xf6, 0x1e, 0xec, 0xb1, 0xf0, 0x54,
0x3b, 0x5e, 0x3e, 0x6a, 0x71, 0xb4, 0xf7, 0x75,
0xc8, 0x16, 0x2f, 0x24, 0x00, 0xde, 0xe9, 0x82,
0x99, 0x5f, 0x33, 0x0b, 0xa9, 0xa6, 0x94, 0xaf,
0xcb, 0x11, 0xc3, 0xf2, 0xdb, 0x09, 0x42, 0x68,
0x29, 0x56, 0x58, 0x01, 0x56, 0xdb, 0x59, 0x03,
0x69, 0xdb, 0x7d, 0x37, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00,
0x0e, 0x00, 0x0e, 0x00, 0x6d, 0x69, 0x63, 0x72,
0x6f, 0x73, 0x6f, 0x66, 0x74, 0x2e, 0x63, 0x6f,
0x6d, 0x00 };
static char g_lic2[20] =
{ 0x80, 0x00, 0x10, 0x00, 0xff, 0x02, 0x10, 0x00,
0x07, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00,
0x28, 0x14, 0x00, 0x00 };
/* mce */
static char g_lic3[20] =
{ 0x80, 0x02, 0x10, 0x00, 0xff, 0x03, 0x10, 0x00,
0x07, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00,
0xf3, 0x99, 0x00, 0x00 };
/*****************************************************************************/
static void APP_CC
hex_to_bin(char* in, char* out)
{
int val;
val = 0;
switch (in[0])
{
case '1': val = 16; break;
case '2': val = 16 * 2; break;
case '3': val = 16 * 3; break;
case '4': val = 16 * 4; break;
case '5': val = 16 * 5; break;
case '6': val = 16 * 6; break;
case '7': val = 16 * 7; break;
case '8': val = 16 * 8; break;
case '9': val = 16 * 9; break;
case 'a': val = 16 * 10; break;
case 'A': val = 16 * 10; break;
case 'b': val = 16 * 11; break;
case 'B': val = 16 * 11; break;
case 'c': val = 16 * 12; break;
case 'C': val = 16 * 12; break;
case 'd': val = 16 * 13; break;
case 'D': val = 16 * 13; break;
case 'e': val = 16 * 14; break;
case 'E': val = 16 * 14; break;
case 'f': val = 16 * 15; break;
case 'F': val = 16 * 15; break;
}
switch (in[1])
{
case '1': val += 1; break;
case '2': val += 2; break;
case '3': val += 3; break;
case '4': val += 4; break;
case '5': val += 5; break;
case '6': val += 6; break;
case '7': val += 7; break;
case '8': val += 8; break;
case '9': val += 9; break;
case 'a': val += 10; break;
case 'A': val += 10; break;
case 'b': val += 11; break;
case 'B': val += 11; break;
case 'c': val += 12; break;
case 'C': val += 12; break;
case 'd': val += 13; break;
case 'D': val += 13; break;
case 'e': val += 14; break;
case 'E': val += 14; break;
case 'f': val += 15; break;
case 'F': val += 15; break;
}
*out = val;
}
/*****************************************************************************/
static void APP_CC
hex_str_to_bin(char* in, char* out, int out_len)
{
int in_index;
int in_len;
int out_index;
char hex[16];
in_len = g_strlen(in);
out_index = 0;
in_index = 0;
while (in_index <= (in_len - 4))
{
if (in[in_index] == '0' && in[in_index + 1] == 'x')
{
hex[0] = in[in_index + 2];
hex[1] = in[in_index + 3];
hex[2] = 0;
if (out_index < out_len)
{
hex_to_bin(hex, out + out_index);
}
out_index++;
}
in_index++;
}
}
/*****************************************************************************/
struct xrdp_sec* APP_CC
xrdp_sec_create(struct xrdp_rdp* owner, int sck, int crypt_level,
int channel_code)
{
struct xrdp_sec* self;
struct list* items;
struct list* values;
int fd;
int index;
char* item;
char* value;
DEBUG((" in xrdp_sec_create"));
self = (struct xrdp_sec*)g_malloc(sizeof(struct xrdp_sec), 1);
self->rdp_layer = owner;
self->rc4_key_size = 1; /* 1 = 40 bit, 2 = 128 bit */
self->crypt_level = 1; /* 1, 2, 3 = low, medium, high */
switch (crypt_level)
{
case 1:
self->rc4_key_size = 1;
self->crypt_level = 1;
break;
case 2:
self->rc4_key_size = 1;
self->crypt_level = 2;
break;
case 3:
self->rc4_key_size = 2;
self->crypt_level = 3;
break;
}
self->channel_code = channel_code;
self->decrypt_rc4_info = ssl_rc4_info_create();
self->encrypt_rc4_info = ssl_rc4_info_create();
g_random(self->server_random, 32);
self->mcs_layer = xrdp_mcs_create(self, sck, &self->client_mcs_data,
&self->server_mcs_data);
fd = g_file_open(XRDP_KEY_FILE); /* rsakeys.ini */
if (fd > 0)
{
items = list_create();
items->auto_free = 1;
values = list_create();
values->auto_free = 1;
file_read_section(fd, "keys", items, values);
for (index = 0; index < items->count; index++)
{
item = (char*)list_get_item(items, index);
value = (char*)list_get_item(values, index);
if (g_strncasecmp(item, "pub_exp", 255) == 0)
{
hex_str_to_bin(value, self->pub_exp, 4);
}
else if (g_strncasecmp(item, "pub_mod", 255) == 0)
{
hex_str_to_bin(value, self->pub_mod, 64);
}
else if (g_strncasecmp(item, "pub_sig", 255) == 0)
{
hex_str_to_bin(value, self->pub_sig, 64);
}
else if (g_strncasecmp(item, "pri_exp", 255) == 0)
{
hex_str_to_bin(value, self->pri_exp, 64);
}
}
list_delete(items);
list_delete(values);
g_file_close(fd);
}
self->chan_layer = xrdp_channel_create(self, self->mcs_layer);
DEBUG((" out xrdp_sec_create"));
return self;
}
/*****************************************************************************/
void APP_CC
xrdp_sec_delete(struct xrdp_sec* self)
{
if (self == 0)
{
return;
}
xrdp_channel_delete(self->chan_layer);
xrdp_mcs_delete(self->mcs_layer);
ssl_rc4_info_delete(self->decrypt_rc4_info);
ssl_rc4_info_delete(self->encrypt_rc4_info);
g_free(self->client_mcs_data.data);
g_free(self->server_mcs_data.data);
g_free(self);
}
/*****************************************************************************/
/* returns error */
int APP_CC
xrdp_sec_init(struct xrdp_sec* self, struct stream* s)
{
if (xrdp_mcs_init(self->mcs_layer, s) != 0)
{
return 1;
}
if (self->crypt_level > 1)
{
s_push_layer(s, sec_hdr, 4 + 8);
}
else
{
s_push_layer(s, sec_hdr, 4);
}
return 0;
}
/*****************************************************************************/
/* Reduce key entropy from 64 to 40 bits */
static void APP_CC
xrdp_sec_make_40bit(char* key)
{
key[0] = 0xd1;
key[1] = 0x26;
key[2] = 0x9e;
}
/*****************************************************************************/
/* returns error */
/* update an encryption key */
static int APP_CC
xrdp_sec_update(char* key, char* update_key, int key_len)
{
char shasig[20];
void* sha1_info;
void* md5_info;
void* rc4_info;
sha1_info = ssl_sha1_info_create();
md5_info = ssl_md5_info_create();
rc4_info = ssl_rc4_info_create();
ssl_sha1_clear(sha1_info);
ssl_sha1_transform(sha1_info, update_key, key_len);
ssl_sha1_transform(sha1_info, g_pad_54, 40);
ssl_sha1_transform(sha1_info, key, key_len);
ssl_sha1_complete(sha1_info, shasig);
ssl_md5_clear(md5_info);
ssl_md5_transform(md5_info, update_key, key_len);
ssl_md5_transform(md5_info, g_pad_92, 48);
ssl_md5_transform(md5_info, shasig, 20);
ssl_md5_complete(md5_info, key);
ssl_rc4_set_key(rc4_info, key, key_len);
ssl_rc4_crypt(rc4_info, key, key_len);
if (key_len == 8)
{
xrdp_sec_make_40bit(key);
}
ssl_sha1_info_delete(sha1_info);
ssl_md5_info_delete(md5_info);
ssl_rc4_info_delete(rc4_info);
return 0;
}
/*****************************************************************************/
static void APP_CC
xrdp_sec_decrypt(struct xrdp_sec* self, char* data, int len)
{
if (self->decrypt_use_count == 4096)
{
xrdp_sec_update(self->decrypt_key, self->decrypt_update_key,
self->rc4_key_len);
ssl_rc4_set_key(self->decrypt_rc4_info, self->decrypt_key,
self->rc4_key_len);
self->decrypt_use_count = 0;
}
ssl_rc4_crypt(self->decrypt_rc4_info, data, len);
self->decrypt_use_count++;
}
/*****************************************************************************/
static void APP_CC
xrdp_sec_encrypt(struct xrdp_sec* self, char* data, int len)
{
if (self->encrypt_use_count == 4096)
{
xrdp_sec_update(self->encrypt_key, self->encrypt_update_key,
self->rc4_key_len);
ssl_rc4_set_key(self->encrypt_rc4_info, self->encrypt_key,
self->rc4_key_len);
self->encrypt_use_count = 0;
}
ssl_rc4_crypt(self->encrypt_rc4_info, data, len);
self->encrypt_use_count++;
}
/*****************************************************************************/
static int APP_CC
unicode_in(struct stream* s, int uni_len, char* dst, int dst_len)
{
int dst_index;
int src_index;
dst_index = 0;
src_index = 0;
while (src_index < uni_len)
{
if (dst_index >= dst_len || src_index > 512)
{
break;
}
in_uint8(s, dst[dst_index]);
in_uint8s(s, 1);
dst_index++;
src_index += 2;
}
in_uint8s(s, 2);
return 0;
}
/*****************************************************************************/
/* returns error */
static int APP_CC
xrdp_sec_process_logon_info(struct xrdp_sec* self, struct stream* s)
{
int flags;
int len_domain;
int len_user;
int len_password;
int len_program;
int len_directory;
//g_hexdump(s->p, 100);
in_uint8s(s, 4);
in_uint32_le(s, flags);
DEBUG(("in xrdp_sec_process_logon_info flags $%x", flags));
/* this is the first test that the decrypt is working */
if ((flags & RDP_LOGON_NORMAL) != RDP_LOGON_NORMAL) /* 0x33 */
{ /* must be or error */
return 1;
}
if (flags & 0x400)
{
self->rdp_layer->client_info.is_mce = 1;
DEBUG(("flag 0x400 found"));
}
if (flags & RDP_LOGON_LEAVE_AUDIO)
{
self->rdp_layer->client_info.sound_code = 1;
DEBUG(("flag RDP_LOGON_LEAVE_AUDIO found"));
}
if ((flags & RDP_LOGON_AUTO) && (!self->rdp_layer->client_info.is_mce))
/* todo, for now not allowing autologon and mce both */
{
self->rdp_layer->client_info.rdp_autologin = 1;
DEBUG(("flag RDP_LOGON_AUTO found"));
}
if (flags & RDP_COMPRESSION)
{
self->rdp_layer->client_info.rdp_compression = 1;
DEBUG(("flag RDP_COMPRESSION found"));
}
in_uint16_le(s, len_domain);
in_uint16_le(s, len_user);
in_uint16_le(s, len_password);
in_uint16_le(s, len_program);
in_uint16_le(s, len_directory);
/* todo, we should error out in any of the above lengths are > 512 */
/* to avoid buffer overruns */
unicode_in(s, len_domain, self->rdp_layer->client_info.domain, 255);
DEBUG(("domain %s", self->rdp_layer->client_info.domain));
unicode_in(s, len_user, self->rdp_layer->client_info.username, 255);
DEBUG(("username %s", self->rdp_layer->client_info.username));
if (flags & RDP_LOGON_AUTO)
{
unicode_in(s, len_password, self->rdp_layer->client_info.password, 255);
DEBUG(("flag RDP_LOGON_AUTO found"));
}
else
{
in_uint8s(s, len_password + 2);
}
unicode_in(s, len_program, self->rdp_layer->client_info.program, 255);
DEBUG(("program %s", self->rdp_layer->client_info.program));
unicode_in(s, len_directory, self->rdp_layer->client_info.directory, 255);
DEBUG(("directory %s", self->rdp_layer->client_info.directory));
DEBUG(("out xrdp_sec_process_logon_info"));
return 0;
}
/*****************************************************************************/
/* returns error */
static int APP_CC
xrdp_sec_send_lic_initial(struct xrdp_sec* self)
{
struct stream* s;
make_stream(s);
init_stream(s, 8192);
if (xrdp_mcs_init(self->mcs_layer, s) != 0)
{
free_stream(s);
return 1;
}
out_uint8a(s, g_lic1, 322);
s_mark_end(s);
if (xrdp_mcs_send(self->mcs_layer, s, MCS_GLOBAL_CHANNEL) != 0)
{
free_stream(s);
return 1;
}
free_stream(s);
return 0;
}
/*****************************************************************************/
/* returns error */
static int APP_CC
xrdp_sec_send_lic_response(struct xrdp_sec* self)
{
struct stream* s;
make_stream(s);
init_stream(s, 8192);
if (xrdp_mcs_init(self->mcs_layer, s) != 0)
{
free_stream(s);
return 1;
}
out_uint8a(s, g_lic2, 20);
s_mark_end(s);
if (xrdp_mcs_send(self->mcs_layer, s, MCS_GLOBAL_CHANNEL) != 0)
{
free_stream(s);
return 1;
}
free_stream(s);
return 0;
}
/*****************************************************************************/
/* returns error */
static int APP_CC
xrdp_sec_send_media_lic_response(struct xrdp_sec* self)
{
struct stream* s;
make_stream(s);
init_stream(s, 8192);
if (xrdp_mcs_init(self->mcs_layer, s) != 0)
{
free_stream(s);
return 1;
}
out_uint8a(s, g_lic3, sizeof(g_lic3));
s_mark_end(s);
if (xrdp_mcs_send(self->mcs_layer, s, MCS_GLOBAL_CHANNEL) != 0)
{
free_stream(s);
return 1;
}
free_stream(s);
return 0;
}
/*****************************************************************************/
static void APP_CC
xrdp_sec_rsa_op(char* out, char* in, char* mod, char* exp)
{
ssl_mod_exp(out, 64, in, 64, mod, 64, exp, 64);
}
/*****************************************************************************/
static void APP_CC
xrdp_sec_hash_48(char* out, char* in, char* salt1, char* salt2, int salt)
{
int i;
void* sha1_info;
void* md5_info;
char pad[4];
char sha1_sig[20];
char md5_sig[16];
sha1_info = ssl_sha1_info_create();
md5_info = ssl_md5_info_create();
for (i = 0; i < 3; i++)
{
g_memset(pad, salt + i, 4);
ssl_sha1_clear(sha1_info);
ssl_sha1_transform(sha1_info, pad, i + 1);
ssl_sha1_transform(sha1_info, in, 48);
ssl_sha1_transform(sha1_info, salt1, 32);
ssl_sha1_transform(sha1_info, salt2, 32);
ssl_sha1_complete(sha1_info, sha1_sig);
ssl_md5_clear(md5_info);
ssl_md5_transform(md5_info, in, 48);
ssl_md5_transform(md5_info, sha1_sig, 20);
ssl_md5_complete(md5_info, md5_sig);
g_memcpy(out + i * 16, md5_sig, 16);
}
ssl_sha1_info_delete(sha1_info);
ssl_md5_info_delete(md5_info);
}
/*****************************************************************************/
static void APP_CC
xrdp_sec_hash_16(char* out, char* in, char* salt1, char* salt2)
{
void* md5_info;
md5_info = ssl_md5_info_create();
ssl_md5_clear(md5_info);
ssl_md5_transform(md5_info, in, 16);
ssl_md5_transform(md5_info, salt1, 32);
ssl_md5_transform(md5_info, salt2, 32);
ssl_md5_complete(md5_info, out);
ssl_md5_info_delete(md5_info);
}
/*****************************************************************************/
static void APP_CC
xrdp_sec_establish_keys(struct xrdp_sec* self)
{
char session_key[48];
char temp_hash[48];
char input[48];
g_memcpy(input, self->client_random, 24);
g_memcpy(input + 24, self->server_random, 24);
xrdp_sec_hash_48(temp_hash, input, self->client_random,
self->server_random, 65);
xrdp_sec_hash_48(session_key, temp_hash, self->client_random,
self->server_random, 88);
g_memcpy(self->sign_key, session_key, 16);
xrdp_sec_hash_16(self->encrypt_key, session_key + 16, self->client_random,
self->server_random);
xrdp_sec_hash_16(self->decrypt_key, session_key + 32, self->client_random,
self->server_random);
if (self->rc4_key_size == 1)
{
xrdp_sec_make_40bit(self->sign_key);
xrdp_sec_make_40bit(self->encrypt_key);
xrdp_sec_make_40bit(self->decrypt_key);
self->rc4_key_len = 8;
}
else
{
self->rc4_key_len = 16;
}
g_memcpy(self->decrypt_update_key, self->decrypt_key, 16);
g_memcpy(self->encrypt_update_key, self->encrypt_key, 16);
ssl_rc4_set_key(self->decrypt_rc4_info, self->decrypt_key, self->rc4_key_len);
ssl_rc4_set_key(self->encrypt_rc4_info, self->encrypt_key, self->rc4_key_len);
}
/*****************************************************************************/
/* returns error */
int APP_CC
xrdp_sec_recv(struct xrdp_sec* self, struct stream* s, int* chan)
{
int flags;
int len;
DEBUG((" in xrdp_sec_recv"));
if (xrdp_mcs_recv(self->mcs_layer, s, chan) != 0)
{
DEBUG((" out xrdp_sec_recv error"));
return 1;
}
in_uint32_le(s, flags);
DEBUG((" in xrdp_sec_recv flags $%x", flags));
if (flags & SEC_ENCRYPT) /* 0x08 */
{
in_uint8s(s, 8); /* signature */
xrdp_sec_decrypt(self, s->p, s->end - s->p);
}
if (flags & SEC_CLIENT_RANDOM) /* 0x01 */
{
in_uint32_le(s, len);
in_uint8a(s, self->client_crypt_random, 64);
xrdp_sec_rsa_op(self->client_random, self->client_crypt_random,
self->pub_mod, self->pri_exp);
xrdp_sec_establish_keys(self);
*chan = 1; /* just set a non existing channel and exit */
DEBUG((" out xrdp_sec_recv"));
return 0;
}
if (flags & SEC_LOGON_INFO) /* 0x40 */
{
if (xrdp_sec_process_logon_info(self, s) != 0)
{
DEBUG((" out xrdp_sec_recv error"));
return 1;
}
if (self->rdp_layer->client_info.is_mce)
{
if (xrdp_sec_send_media_lic_response(self) != 0)
{
DEBUG((" out xrdp_sec_recv error"));
return 1;
}
DEBUG((" out xrdp_sec_recv"));
return -1; /* special error that means send demand active */
}
if (xrdp_sec_send_lic_initial(self) != 0)
{
DEBUG((" out xrdp_sec_recv error"));
return 1;
}
*chan = 1; /* just set a non existing channel and exit */
DEBUG((" out xrdp_sec_recv"));
return 0;
}
if (flags & SEC_LICENCE_NEG) /* 0x80 */
{
if (xrdp_sec_send_lic_response(self) != 0)
{
DEBUG((" out xrdp_sec_recv error"));
return 1;
}
DEBUG((" out xrdp_sec_recv"));
return -1; /* special error that means send demand active */
}
DEBUG((" out xrdp_sec_recv"));
return 0;
}
/*****************************************************************************/
/* Output a uint32 into a buffer (little-endian) */
static void
buf_out_uint32(char* buffer, int value)
{
buffer[0] = (value) & 0xff;
buffer[1] = (value >> 8) & 0xff;
buffer[2] = (value >> 16) & 0xff;
buffer[3] = (value >> 24) & 0xff;
}
/*****************************************************************************/
/* Generate a MAC hash (5.2.3.1), using a combination of SHA1 and MD5 */
static void APP_CC
xrdp_sec_sign(struct xrdp_sec* self, char* out, int out_len,
char* data, int data_len)
{
char shasig[20];
char md5sig[16];
char lenhdr[4];
void* sha1_info;
void* md5_info;
buf_out_uint32(lenhdr, data_len);
sha1_info = ssl_sha1_info_create();
md5_info = ssl_md5_info_create();
ssl_sha1_clear(sha1_info);
ssl_sha1_transform(sha1_info, self->sign_key, self->rc4_key_len);
ssl_sha1_transform(sha1_info, g_pad_54, 40);
ssl_sha1_transform(sha1_info, lenhdr, 4);
ssl_sha1_transform(sha1_info, data, data_len);
ssl_sha1_complete(sha1_info, shasig);
ssl_md5_clear(md5_info);
ssl_md5_transform(md5_info, self->sign_key, self->rc4_key_len);
ssl_md5_transform(md5_info, g_pad_92, 48);
ssl_md5_transform(md5_info, shasig, 20);
ssl_md5_complete(md5_info, md5sig);
g_memcpy(out, md5sig, out_len);
ssl_sha1_info_delete(sha1_info);
ssl_md5_info_delete(md5_info);
}
/*****************************************************************************/
/* returns error */
int APP_CC
xrdp_sec_send(struct xrdp_sec* self, struct stream* s, int chan)
{
int datalen;
DEBUG((" in xrdp_sec_send"));
s_pop_layer(s, sec_hdr);
if (self->crypt_level > 1)
{
out_uint32_le(s, SEC_ENCRYPT);
datalen = (s->end - s->p) - 8;
xrdp_sec_sign(self, s->p, 8, s->p + 8, datalen);
xrdp_sec_encrypt(self, s->p + 8, datalen);
}
else
{
out_uint32_le(s, 0);
}
if (xrdp_mcs_send(self->mcs_layer, s, chan) != 0)
{
return 1;
}
DEBUG((" out xrdp_sec_send"));
return 0;
}
/*****************************************************************************/
/* this adds the mcs channels in the list of channels to be used when
creating the server mcs data */
static int APP_CC
xrdp_sec_process_mcs_data_channels(struct xrdp_sec* self, struct stream* s)
{
int num_channels;
int index;
struct mcs_channel_item* channel_item;
DEBUG(("processing channels, channel_code is %d", self->channel_code));
/* this is an option set in xrdp.ini */
if (self->channel_code != 1) /* are channels on? */
{
return 0;
}
in_uint32_le(s, num_channels);
for (index = 0; index < num_channels; index++)
{
channel_item = (struct mcs_channel_item*)
g_malloc(sizeof(struct mcs_channel_item), 1);
in_uint8a(s, channel_item->name, 8);
in_uint32_be(s, channel_item->flags);
channel_item->chanid = MCS_GLOBAL_CHANNEL + (index + 1);
list_add_item(self->mcs_layer->channel_list, (long)channel_item);
DEBUG(("got channel flags %8.8x name %s", channel_item->flags,
channel_item->name));
}
return 0;
}
/*****************************************************************************/
/* process client mcs data, we need some things in here to create the server
mcs data */
int APP_CC
xrdp_sec_process_mcs_data(struct xrdp_sec* self)
{
struct stream* s;
char* hold_p;
int tag;
int size;
s = &self->client_mcs_data;
/* set p to beginning */
s->p = s->data;
/* skip header */
in_uint8s(s, 23);
while (s_check_rem(s, 4))
{
hold_p = s->p;
in_uint16_le(s, tag);
in_uint16_le(s, size);
if (size < 4 || !s_check_rem(s, size - 4))
{
g_writeln("error in xrdp_sec_process_mcs_data tag %d size %d",
tag, size);
break;
}
switch (tag)
{
case SEC_TAG_CLI_INFO:
break;
case SEC_TAG_CLI_CRYPT:
break;
case SEC_TAG_CLI_CHANNELS:
xrdp_sec_process_mcs_data_channels(self, s);
break;
case SEC_TAG_CLI_4:
break;
default:
g_writeln("error unknown xrdp_sec_process_mcs_data tag %d size %d",
tag, size);
break;
}
s->p = hold_p + size;
}
/* set p to beginning */
s->p = s->data;
return 0;
}
/*****************************************************************************/
/* prepare server mcs data to send in mcs layer */
int APP_CC
xrdp_sec_out_mcs_data(struct xrdp_sec* self)
{
struct stream* s;
int num_channels_even;
int num_channels;
int index;
int channel;
num_channels = self->mcs_layer->channel_list->count;
num_channels_even = num_channels + (num_channels & 1);
s = &self->server_mcs_data;
init_stream(s, 512);
out_uint16_be(s, 5);
out_uint16_be(s, 0x14);
out_uint8(s, 0x7c);
out_uint16_be(s, 1);
out_uint8(s, 0x2a);
out_uint8(s, 0x14);
out_uint8(s, 0x76);
out_uint8(s, 0x0a);
out_uint8(s, 1);
out_uint8(s, 1);
out_uint8(s, 0);
out_uint16_le(s, 0xc001);
out_uint8(s, 0);
out_uint8(s, 0x4d); /* M */
out_uint8(s, 0x63); /* c */
out_uint8(s, 0x44); /* D */
out_uint8(s, 0x6e); /* n */
out_uint16_be(s, 0x80fc + (num_channels_even * 2));
out_uint16_le(s, SEC_TAG_SRV_INFO);
out_uint16_le(s, 8); /* len */
out_uint8(s, 4); /* 4 = rdp5 1 = rdp4 */
out_uint8(s, 0);
out_uint8(s, 8);
out_uint8(s, 0);
out_uint16_le(s, SEC_TAG_SRV_CHANNELS);
out_uint16_le(s, 8 + (num_channels_even * 2)); /* len */
out_uint16_le(s, MCS_GLOBAL_CHANNEL); /* 1003, 0x03eb main channel */
out_uint16_le(s, num_channels); /* number of other channels */
for (index = 0; index < num_channels_even; index++)
{
if (index < num_channels)
{
channel = MCS_GLOBAL_CHANNEL + (index + 1);
out_uint16_le(s, channel);
}
else
{
out_uint16_le(s, 0);
}
}
out_uint16_le(s, SEC_TAG_SRV_CRYPT);
out_uint16_le(s, 0x00ec); /* len is 236 */
out_uint32_le(s, self->rc4_key_size); /* key len 1 = 40 bit 2 = 128 bit */
out_uint32_le(s, self->crypt_level); /* crypt level 1 = low 2 = medium */
/* 3 = high */
out_uint32_le(s, 32); /* 32 bytes random len */
out_uint32_le(s, 0xb8); /* 184 bytes rsa info(certificate) len */
out_uint8a(s, self->server_random, 32);
/* here to end is certificate */
/* HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ */
/* TermService\Parameters\Certificate */
out_uint32_le(s, 1);
out_uint32_le(s, 1);
out_uint32_le(s, 1);
out_uint16_le(s, SEC_TAG_PUBKEY);
out_uint16_le(s, 0x005c); /* 92 bytes length of SEC_TAG_PUBKEY */
out_uint32_le(s, SEC_RSA_MAGIC);
out_uint32_le(s, 0x48); /* 72 bytes modulus len */
out_uint32_be(s, 0x00020000);
out_uint32_be(s, 0x3f000000);
out_uint8a(s, self->pub_exp, 4); /* pub exp */
out_uint8a(s, self->pub_mod, 64); /* pub mod */
out_uint8s(s, 8); /* pad */
out_uint16_le(s, SEC_TAG_KEYSIG);
out_uint16_le(s, 72); /* len */
out_uint8a(s, self->pub_sig, 64); /* pub sig */
out_uint8s(s, 8); /* pad */
/* end certificate */
s_mark_end(s);
return 0;
}
/*****************************************************************************/
/* process the mcs client data we received from the mcs layer */
static void APP_CC
xrdp_sec_in_mcs_data(struct xrdp_sec* self)
{
struct stream* s;
struct xrdp_client_info* client_info;
int index;
char c;
client_info = &self->rdp_layer->client_info;
s = &self->client_mcs_data;
/* get hostname, its unicode */
s->p = s->data;
in_uint8s(s, 47);
g_memset(client_info->hostname, 0, 32);
c = 1;
index = 0;
while (index < 16 && c != 0)
{
in_uint8(s, c);
in_uint8s(s, 1);
client_info->hostname[index] = c;
index++;
}
/* get build */
s->p = s->data;
in_uint8s(s, 43);
in_uint32_le(s, client_info->build);
/* get keylayout */
s->p = s->data;
in_uint8s(s, 39);
in_uint32_le(s, client_info->keylayout);
s->p = s->data;
}
/*****************************************************************************/
int APP_CC
xrdp_sec_incoming(struct xrdp_sec* self)
{
DEBUG((" in xrdp_sec_incoming"));
if (xrdp_mcs_incoming(self->mcs_layer) != 0)
{
return 1;
}
#ifdef XRDP_DEBUG
g_writeln("client mcs data received");
g_hexdump(self->client_mcs_data.data,
self->client_mcs_data.end - self->client_mcs_data.data);
g_writeln("server mcs data sent");
g_hexdump(self->server_mcs_data.data,
self->server_mcs_data.end - self->server_mcs_data.data);
#endif
DEBUG((" out xrdp_sec_incoming"));
xrdp_sec_in_mcs_data(self);
return 0;
}
/*****************************************************************************/
int APP_CC
xrdp_sec_disconnect(struct xrdp_sec* self)
{
int rv;
DEBUG((" in xrdp_sec_disconnect"));
rv = xrdp_mcs_disconnect(self->mcs_layer);
DEBUG((" out xrdp_sec_disconnect"));
return rv;
}