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-rw-r--r--uirdesktop/mppc.c380
1 files changed, 0 insertions, 380 deletions
diff --git a/uirdesktop/mppc.c b/uirdesktop/mppc.c
deleted file mode 100644
index cc126c15..00000000
--- a/uirdesktop/mppc.c
+++ /dev/null
@@ -1,380 +0,0 @@
-/* -*- c-basic-offset: 8 -*-
- rdesktop: A Remote Desktop Protocol client.
- Protocol services - RDP decompression
- Copyright (C) Matthew Chapman 1999-2005
-
- 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.
-*/
-
-#include <stdio.h>
-#include <string.h>
-
-#include "rdesktop.h"
-
-/* mppc decompression */
-/* http://www.faqs.org/rfcs/rfc2118.html */
-
-/* Contacts: */
-
-/* hifn contact mentioned in the faq is */
-/* Robert Friend rfriend at hifn dot com */
-
-/* if you have questions regarding MPPC */
-/* our contact is */
-/* Guus Dhaeze GDhaeze at hifn dot com */
-
-/* Licensing: */
-
-/* decompression is alright as long as we */
-/* don't compress data */
-
-/* Algorithm: */
-
-/* as the rfc states the algorithm seems to */
-/* be LZ77 with a sliding buffer */
-/* that is empty at init. */
-
-/* the algorithm is called LZS and is */
-/* patented for another couple of years. */
-
-/* more information is available in */
-/* http://www.ietf.org/ietf/IPR/hifn-ipr-draft-friend-tls-lzs-compression.txt */
-
-
-RDPCOMP g_mppc_dict;
-
-int
-mppc_expand(uint8 * data, uint32 clen, uint8 ctype, uint32 * roff, uint32 * rlen)
-{
- int k, walker_len = 0, walker;
- uint32 i = 0;
- int next_offset, match_off;
- int match_len;
- int old_offset, match_bits;
- BOOL big = ctype & RDP_MPPC_BIG ? True : False;
-
- uint8 *dict = g_mppc_dict.hist;
-
- if ((ctype & RDP_MPPC_COMPRESSED) == 0)
- {
- *roff = 0;
- *rlen = clen;
- return 0;
- }
-
- if ((ctype & RDP_MPPC_RESET) != 0)
- {
- g_mppc_dict.roff = 0;
- }
-
- if ((ctype & RDP_MPPC_FLUSH) != 0)
- {
- memset(dict, 0, RDP_MPPC_DICT_SIZE);
- g_mppc_dict.roff = 0;
- }
-
- *roff = 0;
- *rlen = 0;
-
- walker = g_mppc_dict.roff;
-
- next_offset = walker;
- old_offset = next_offset;
- *roff = old_offset;
- if (clen == 0)
- return 0;
- clen += i;
-
- do
- {
- if (walker_len == 0)
- {
- if (i >= clen)
- break;
- walker = data[i++] << 24;
- walker_len = 8;
- }
- if (walker >= 0)
- {
- if (walker_len < 8)
- {
- if (i >= clen)
- {
- if (walker != 0)
- return -1;
- break;
- }
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- walker_len += 8;
- }
- if (next_offset >= RDP_MPPC_DICT_SIZE)
- return -1;
- dict[next_offset++] = (((uint32) walker) >> ((uint32) 24));
- walker <<= 8;
- walker_len -= 8;
- continue;
- }
- walker <<= 1;
- /* fetch next 8-bits */
- if (--walker_len == 0)
- {
- if (i >= clen)
- return -1;
- walker = data[i++] << 24;
- walker_len = 8;
- }
- /* literal decoding */
- if (walker >= 0)
- {
- if (walker_len < 8)
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- walker_len += 8;
- }
- if (next_offset >= RDP_MPPC_DICT_SIZE)
- return -1;
- dict[next_offset++] = (uint8) (walker >> 24 | 0x80);
- walker <<= 8;
- walker_len -= 8;
- continue;
- }
-
- /* decode offset */
- /* length pair */
- walker <<= 1;
- if (--walker_len < (big ? 3 : 2))
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- walker_len += 8;
- }
-
- if (big)
- {
- /* offset decoding where offset len is:
- -63: 11111 followed by the lower 6 bits of the value
- 64-319: 11110 followed by the lower 8 bits of the value ( value - 64 )
- 320-2367: 1110 followed by lower 11 bits of the value ( value - 320 )
- 2368-65535: 110 followed by lower 16 bits of the value ( value - 2368 )
- */
- switch (((uint32) walker) >> ((uint32) 29))
- {
- case 7: /* - 63 */
- for (; walker_len < 9; walker_len += 8)
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- }
- walker <<= 3;
- match_off = ((uint32) walker) >> ((uint32) 26);
- walker <<= 6;
- walker_len -= 9;
- break;
-
- case 6: /* 64 - 319 */
- for (; walker_len < 11; walker_len += 8)
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- }
-
- walker <<= 3;
- match_off = (((uint32) walker) >> ((uint32) 24)) + 64;
- walker <<= 8;
- walker_len -= 11;
- break;
-
- case 5:
- case 4: /* 320 - 2367 */
- for (; walker_len < 13; walker_len += 8)
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- }
-
- walker <<= 2;
- match_off = (((uint32) walker) >> ((uint32) 21)) + 320;
- walker <<= 11;
- walker_len -= 13;
- break;
-
- default: /* 2368 - 65535 */
- for (; walker_len < 17; walker_len += 8)
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- }
-
- walker <<= 1;
- match_off = (((uint32) walker) >> ((uint32) 16)) + 2368;
- walker <<= 16;
- walker_len -= 17;
- break;
- }
- }
- else
- {
- /* offset decoding where offset len is:
- -63: 1111 followed by the lower 6 bits of the value
- 64-319: 1110 followed by the lower 8 bits of the value ( value - 64 )
- 320-8191: 110 followed by the lower 13 bits of the value ( value - 320 )
- */
- switch (((uint32) walker) >> ((uint32) 30))
- {
- case 3: /* - 63 */
- if (walker_len < 8)
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- walker_len += 8;
- }
- walker <<= 2;
- match_off = ((uint32) walker) >> ((uint32) 26);
- walker <<= 6;
- walker_len -= 8;
- break;
-
- case 2: /* 64 - 319 */
- for (; walker_len < 10; walker_len += 8)
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- }
-
- walker <<= 2;
- match_off = (((uint32) walker) >> ((uint32) 24)) + 64;
- walker <<= 8;
- walker_len -= 10;
- break;
-
- default: /* 320 - 8191 */
- for (; walker_len < 14; walker_len += 8)
- {
- if (i >= clen)
- return -1;
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- }
-
- match_off = (walker >> 18) + 320;
- walker <<= 14;
- walker_len -= 14;
- break;
- }
- }
- if (walker_len == 0)
- {
- if (i >= clen)
- return -1;
- walker = data[i++] << 24;
- walker_len = 8;
- }
-
- /* decode length of match */
- match_len = 0;
- if (walker >= 0)
- { /* special case - length of 3 is in bit 0 */
- match_len = 3;
- walker <<= 1;
- walker_len--;
- }
- else
- {
- /* this is how it works len of:
- 4-7: 10 followed by 2 bits of the value
- 8-15: 110 followed by 3 bits of the value
- 16-31: 1110 followed by 4 bits of the value
- 32-63: .... and so forth
- 64-127:
- 128-255:
- 256-511:
- 512-1023:
- 1024-2047:
- 2048-4095:
- 4096-8191:
-
- i.e. 4097 is encoded as: 111111111110 000000000001
- meaning 4096 + 1...
- */
- match_bits = big ? 14 : 11; /* 11 or 14 bits of value at most */
- do
- {
- walker <<= 1;
- if (--walker_len == 0)
- {
- if (i >= clen)
- return -1;
- walker = data[i++] << 24;
- walker_len = 8;
- }
- if (walker >= 0)
- break;
- if (--match_bits == 0)
- {
- return -1;
- }
- }
- while (1);
- match_len = (big ? 16 : 13) - match_bits;
- walker <<= 1;
- if (--walker_len < match_len)
- {
- for (; walker_len < match_len; walker_len += 8)
- {
- if (i >= clen)
- {
- return -1;
- }
- walker |= (data[i++] & 0xff) << (24 - walker_len);
- }
- }
-
- match_bits = match_len;
- match_len =
- ((walker >> (32 - match_bits)) & (~(-1 << match_bits))) | (1 <<
- match_bits);
- walker <<= match_bits;
- walker_len -= match_bits;
- }
- if (next_offset + match_len >= RDP_MPPC_DICT_SIZE)
- {
- return -1;
- }
- /* memory areas can overlap - meaning we can't use memXXX functions */
- k = (next_offset - match_off) & (big ? 65535 : 8191);
- do
- {
- dict[next_offset++] = dict[k++];
- }
- while (--match_len != 0);
- }
- while (1);
-
- /* store history offset */
- g_mppc_dict.roff = next_offset;
-
- *roff = old_offset;
- *rlen = next_offset - old_offset;
-
- return 0;
-}
generated by cgit v1.2.3 (git 2.46.0) at 2025-11-30 15:56:10 +0000