1 /*
2    rdesktop: A Remote Desktop Protocol client.
3    Parsing primitives
4    Copyright (C) Matthew Chapman 1999-2005
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 2 of the License, or
9    (at your option) any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License along
17    with this program; if not, write to the Free Software Foundation, Inc.,
18    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19 */
20 
21 /* Parser state */
22 typedef struct stream
23 {
24 	unsigned char *p;
25 	unsigned char *end;
26 	unsigned char *data;
27 	unsigned int size;
28 
29 	/* Offsets of various headers */
30 	unsigned char *iso_hdr;
31 	unsigned char *mcs_hdr;
32 	unsigned char *sec_hdr;
33 	unsigned char *rdp_hdr;
34 	unsigned char *channel_hdr;
35 
36 }
37  *STREAM;
38 
39 #define s_push_layer(s,h,n)	{ (s)->h = (s)->p; (s)->p += n; }
40 #define s_pop_layer(s,h)	(s)->p = (s)->h;
41 #define s_mark_end(s)		(s)->end = (s)->p;
42 #define s_check(s)		((s)->p <= (s)->end)
43 #define s_check_rem(s,n)	((s)->p + n <= (s)->end)
44 #define s_check_end(s)		((s)->p == (s)->end)
45 
46 #if defined(L_ENDIAN) && !defined(NEED_ALIGN)
47 #define in_uint16_le(s,v)	{ v = *(uint16 *)((s)->p); (s)->p += 2; }
48 #define in_uint32_le(s,v)	{ v = *(uint32 *)((s)->p); (s)->p += 4; }
49 #define out_uint16_le(s,v)	{ *(uint16 *)((s)->p) = v; (s)->p += 2; }
50 #define out_uint32_le(s,v)	{ *(uint32 *)((s)->p) = v; (s)->p += 4; }
51 
52 #else
53 #define in_uint16_le(s,v)	{ v = *((s)->p++); v += *((s)->p++) << 8; }
54 #define in_uint32_le(s,v)	{ in_uint16_le(s,v) \
55 				v += *((s)->p++) << 16; v += *((s)->p++) << 24; }
56 #define out_uint16_le(s,v)	{ *((s)->p++) = (v) & 0xff; *((s)->p++) = ((v) >> 8) & 0xff; }
57 #define out_uint32_le(s,v)	{ out_uint16_le(s, (v) & 0xffff); out_uint16_le(s, ((v) >> 16) & 0xffff); }
58 #endif
59 
60 #if defined(B_ENDIAN) && !defined(NEED_ALIGN)
61 #define in_uint16_be(s,v)	{ v = *(uint16 *)((s)->p); (s)->p += 2; }
62 #define in_uint32_be(s,v)	{ v = *(uint32 *)((s)->p); (s)->p += 4; }
63 #define out_uint16_be(s,v)	{ *(uint16 *)((s)->p) = v; (s)->p += 2; }
64 #define out_uint32_be(s,v)	{ *(uint32 *)((s)->p) = v; (s)->p += 4; }
65 
66 #define B_ENDIAN_PREFERRED
67 #define in_uint16(s,v)		in_uint16_be(s,v)
68 #define in_uint32(s,v)		in_uint32_be(s,v)
69 #define out_uint16(s,v)		out_uint16_be(s,v)
70 #define out_uint32(s,v)		out_uint32_be(s,v)
71 
72 #else
73 #define in_uint16_be(s,v)	{ v = *((s)->p++); next_be(s,v); }
74 #define in_uint32_be(s,v)	{ in_uint16_be(s,v); next_be(s,v); next_be(s,v); }
75 #define out_uint16_be(s,v)	{ *((s)->p++) = (uint8)((v) >> 8) & 0xff; *((s)->p++) = (uint8)((v) & 0xff); }
76 #define out_uint32_be(s,v)	{ out_uint16_be(s, (uint16)(((v) >> 16) & 0xffff)); out_uint16_be(s, (uint16)((v) & 0xffff)); }
77 #endif
78 
79 #ifndef B_ENDIAN_PREFERRED
80 #define in_uint16(s,v)		in_uint16_le(s,v)
81 #define in_uint32(s,v)		in_uint32_le(s,v)
82 #define out_uint16(s,v)		out_uint16_le(s,v)
83 #define out_uint32(s,v)		out_uint32_le(s,v)
84 #endif
85 
86 #define in_uint8(s,v)		v = *((s)->p++);
87 #define in_uint8p(s,v,n)	{ v = (s)->p; (s)->p += n; }
88 #define in_uint8a(s,v,n)	{ memcpy(v,(s)->p,n); (s)->p += n; }
89 #define in_uint8s(s,n)		(s)->p += n;
90 #define out_uint8(s,v)		*((s)->p++) = v;
91 #define out_uint8p(s,v,n)	{ memcpy((s)->p,v,n); (s)->p += n; }
92 #define out_uint8a(s,v,n)	out_uint8p(s,v,n);
93 #define out_uint8s(s,n)		{ memset((s)->p,0,n); (s)->p += n; }
94 
95 #define next_be(s,v)		v = ((v) << 8) + *((s)->p++);
96