/** * FreeRDP: A Remote Desktop Protocol Client * Implements Microsoft Point to Point Compression (MPPC) protocol * * Copyright 2011 Laxmikant Rashinkar * * 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. */ #include "rdp.h" #if 0 static uint8 HuffLengthLEC[] = { 0x6, 0x6, 0x6, 0x6, 0x7, 0x7, 0x7, 0x7, 0x7, 0x7, 0x7, 0x7, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x9, 0x8, 0x9, 0x9, 0x9, 0x9, 0x8, 0x8, 0x9, 0x9, 0x9, 0x9, 0x9, 0x8, 0x9, 0x9, 0xa, 0x9, 0x9, 0x9, 0x9, 0x9, 0x9, 0x9, 0xa, 0x9, 0xa, 0xa, 0xa, 0x9, 0x9, 0x9, 0xa, 0x9, 0xa, 0xa, 0xa, 0x9, 0x9, 0xa, 0xa, 0x9, 0xa, 0x9, 0x9, 0x8, 0x9, 0x9, 0x9, 0x9, 0xa, 0xa, 0xa, 0x9, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x8, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0x7, 0x9, 0x9, 0xa, 0x9, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xd, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xb, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0xa, 0x9, 0xa, 0x8, 0x9, 0x9, 0xa, 0x9, 0xa, 0xa, 0xa, 0x9, 0xa, 0xa, 0xa, 0x9, 0x9, 0x8, 0x7, 0xd, 0xd, 0x7, 0x7, 0xa, 0x7, 0x7, 0x6, 0x6, 0x6, 0x6, 0x5, 0x6, 0x6, 0x6, 0x5, 0x6, 0x5, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x6, 0x8, 0x5, 0x6, 0x7, 0x7 }; #endif static uint16 HuffIndexLEC[512] = { 0x007b, 0xff1f, 0xff0d, 0xfe27, 0xfe00, 0xff05, 0xff17, 0xfe68, 0x00c5, 0xfe07, 0xff13, 0xfec0, 0xff08, 0xfe18, 0xff1b, 0xfeb3, 0xfe03, 0x00a2, 0xfe42, 0xff10, 0xfe0b, 0xfe02, 0xfe91, 0xff19, 0xfe80, 0x00e9, 0xfe3a, 0xff15, 0xfe12, 0x0057, 0xfed7, 0xff1d, 0xff0e, 0xfe35, 0xfe69, 0xff22, 0xff18, 0xfe7a, 0xfe01, 0xff23, 0xff14, 0xfef4, 0xfeb4, 0xfe09, 0xff1c, 0xfec4, 0xff09, 0xfe60, 0xfe70, 0xff12, 0xfe05, 0xfe92, 0xfea1, 0xff1a, 0xfe0f, 0xff07, 0xfe56, 0xff16, 0xff02, 0xfed8, 0xfee8, 0xff1e, 0xfe1d, 0x003b, 0xffff, 0xff06, 0xffff, 0xfe71, 0xfe89, 0xffff, 0xffff, 0xfe2c, 0xfe2b, 0xfe20, 0xffff, 0xfebb, 0xfecf, 0xfe08, 0xffff, 0xfee0, 0xfe0d, 0xffff, 0xfe99, 0xffff, 0xfe04, 0xfeaa, 0xfe49, 0xffff, 0xfe17, 0xfe61, 0xfedf, 0xffff, 0xfeff, 0xfef6, 0xfe4c, 0xffff, 0xffff, 0xfe87, 0xffff, 0xff24, 0xffff, 0xfe3c, 0xfe72, 0xffff, 0xffff, 0xfece, 0xffff, 0xfefe, 0xffff, 0xfe23, 0xfebc, 0xfe0a, 0xfea9, 0xffff, 0xfe11, 0xffff, 0xfe82, 0xffff, 0xfe06, 0xfe9a, 0xfef5, 0xffff, 0xfe22, 0xfe4d, 0xfe5f, 0xffff, 0xff03, 0xfee1, 0xffff, 0xfeca, 0xfecc, 0xffff, 0xfe19, 0xffff, 0xfeb7, 0xffff, 0xffff, 0xfe83, 0xfe29, 0xffff, 0xffff, 0xffff, 0xfe6c, 0xffff, 0xfeed, 0xffff, 0xffff, 0xfe46, 0xfe5c, 0xfe15, 0xffff, 0xfedb, 0xfea6, 0xffff, 0xffff, 0xfe44, 0xffff, 0xfe0c, 0xffff, 0xfe95, 0xfefc, 0xffff, 0xffff, 0xfeb8, 0x16c9, 0xffff, 0xfef0, 0xffff, 0xfe38, 0xffff, 0xffff, 0xfe6d, 0xfe7e, 0xffff, 0xffff, 0xffff, 0xffff, 0xfe5b, 0xfedc, 0xffff, 0xffff, 0xfeec, 0xfe47, 0xfe1f, 0xffff, 0xfe7f, 0xfe96, 0xffff, 0xffff, 0xfea5, 0xffff, 0xfe10, 0xfe40, 0xfe32, 0xfebf, 0xffff, 0xffff, 0xfed4, 0xfef1, 0xffff, 0xffff, 0xffff, 0xfe75, 0xffff, 0xffff, 0xfe8d, 0xfe31, 0xffff, 0xfe65, 0xfe1b, 0xffff, 0xfee4, 0xfefb, 0xffff, 0xffff, 0xfe52, 0xffff, 0xfe0e, 0xffff, 0xfe9d, 0xfeaf, 0xffff, 0xffff, 0xfe51, 0xfed3, 0xffff, 0xff20, 0xffff, 0xfe2f, 0xffff, 0xffff, 0xfec1, 0xfe8c, 0xffff, 0xffff, 0xffff, 0xfe3f, 0xffff, 0xffff, 0xfe76, 0xffff, 0xfefa, 0xfe53, 0xfe25, 0xffff, 0xfe64, 0xfee5, 0xffff, 0xffff, 0xfeae, 0xffff, 0xfe13, 0xffff, 0xfe88, 0xfe9e, 0xffff, 0xfe43, 0xffff, 0xffff, 0xfea4, 0xfe93, 0xffff, 0xffff, 0xffff, 0xfe3d, 0xffff, 0xffff, 0xfeeb, 0xfed9, 0xffff, 0xfe14, 0xfe5a, 0xffff, 0xfe28, 0xfe7d, 0xffff, 0xffff, 0xfe6a, 0xffff, 0xffff, 0xff01, 0xfec6, 0xfec8, 0xffff, 0xffff, 0xfeb5, 0xffff, 0xffff, 0xffff, 0xfe94, 0xfe78, 0xffff, 0xffff, 0xffff, 0xfea3, 0xffff, 0xffff, 0xfeda, 0xfe58, 0xffff, 0xfe1e, 0xfe45, 0xfeea, 0xffff, 0xfe6b, 0xffff, 0xffff, 0xfe37, 0xffff, 0xffff, 0xffff, 0xfe7c, 0xfeb6, 0xffff, 0xffff, 0xfef8, 0xffff, 0xffff, 0xffff, 0xfec7, 0xfe9b, 0xffff, 0xffff, 0xffff, 0xfe50, 0xffff, 0xffff, 0xfead, 0xfee2, 0xffff, 0xfe1a, 0xfe63, 0xfe4e, 0xffff, 0xffff, 0xfef9, 0xffff, 0xfe73, 0xffff, 0xffff, 0xffff, 0xfe30, 0xfe8b, 0xffff, 0xffff, 0xfebd, 0xfe2e, 0x0100, 0xffff, 0xfeee, 0xfed2, 0xffff, 0xffff, 0xffff, 0xfeac, 0xffff, 0xffff, 0xfe9c, 0xfe84, 0xffff, 0xfe24, 0xfe4f, 0xfef7, 0xffff, 0xffff, 0xfee3, 0xfe62, 0xffff, 0xffff, 0xffff, 0xffff, 0xfe8a, 0xfe74, 0xffff, 0xffff, 0xfe3e, 0xffff, 0xffff, 0xffff, 0xfed1, 0xfebe, 0xffff, 0xffff, 0xfe2d, 0xffff, 0xfe4a, 0xfef3, 0xffff, 0xffff, 0xfedd, 0xfe5e, 0xfe16, 0xffff, 0xfe48, 0xfea8, 0xffff, 0xfeab, 0xfe97, 0xffff, 0xffff, 0xfed0, 0xffff, 0xffff, 0xfecd, 0xfeb9, 0xffff, 0xffff, 0xffff, 0xfe2a, 0xffff, 0xffff, 0xfe86, 0xfe6e, 0xffff, 0xffff, 0xffff, 0xfede, 0xffff, 0xffff, 0xfe5d, 0xfe4b, 0xfe21, 0xffff, 0xfeef, 0xfe98, 0xffff, 0xffff, 0xfe81, 0xffff, 0xffff, 0xffff, 0xfea7, 0xffff, 0xfeba, 0xfefd, 0xffff, 0xffff, 0xffff, 0xfecb, 0xffff, 0xffff, 0xfe6f, 0xfe39, 0xffff, 0xffff, 0xffff, 0xfe85, 0xffff, 0x010c, 0xfee6, 0xfe67, 0xfe1c, 0xffff, 0xfe54, 0xfeb2, 0xffff, 0xffff, 0xfe9f, 0xffff, 0xffff, 0xffff, 0xfe59, 0xfeb1, 0xffff, 0xfec2, 0xffff, 0xffff, 0xfe36, 0xfef2, 0xffff, 0xffff, 0xfed6, 0xfe77, 0xffff, 0xffff, 0xffff, 0xfe33, 0xffff, 0xffff, 0xfe8f, 0xfe55, 0xfe26, 0x010a, 0xff04, 0xfee7, 0xffff, 0x0121, 0xfe66, 0xffff, 0xffff, 0xffff, 0xfeb0, 0xfea0, 0xffff, 0x010f, 0xfe90, 0xffff, 0xffff, 0xfed5, 0xffff, 0xffff, 0xfec3, 0xfe34, 0xffff, 0xffff, 0xffff, 0xfe8e, 0xffff, 0x0111, 0xfe79, 0xfe41, 0x010b }; static uint16 LECHTab[] = { 511, 0, 508, 448, 494, 347, 486, 482 }; #if 0 static uint8 HuffLenLOM[] = { 0x4, 0x2, 0x3, 0x4, 0x3, 0x4, 0x4, 0x5, 0x4, 0x5, 0x5, 0x6, 0x6, 0x7, 0x7, 0x8, 0x7, 0x8, 0x8, 0x9, 0x9, 0x8, 0x9, 0x9, 0x9, 0x9, 0x9, 0x9, 0x9, 0x9, 0x9, 0x9 }; #endif static uint16 HuffIndexLOM[] = { 0x0fe1, 0x0fe0, 0x0fe2, 0x0fe8, 0x000e, 0x0fe5, 0x0fe4, 0x0fea, 0x0ff1, 0x0fe3, 0x0015, 0x0fe7, 0x0fef, 0x0046, 0x0ff0, 0x0fed, 0x0fff, 0x0ff7, 0x0ffb, 0x0019, 0x0ffd, 0x0ff4, 0x012c, 0x0feb, 0x0ffe, 0x0ff6, 0x0ffa, 0x0089, 0x0ffc, 0x0ff3, 0x0ff8, 0x0ff2 }; static uint8 LOMHTab[] = { 0, 4, 10, 19 }; #if 0 static uint8 CopyOffsetBitsLUT[] = { 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 15 }; static uint32 CopyOffsetBaseLUT[] = { 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577, 32769, 49153, 65537 }; static uint8 LoMBitsLUT[] = { 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 6, 6, 8, 8, 14, 14 }; static uint16 LoMBaseLUT[] = { 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 22, 26, 30, 34, 42, 50, 58, 66, 82, 98, 114, 130, 194, 258, 514, 2, 2 }; #endif uint16 LEChash(uint16 key) { return ((key & 0x1ff) ^ (key >> 9) ^ (key >> 4) ^ (key >> 7)); } uint16 LOMhash(uint16 key) { return ((key & 0x1f) ^ (key >> 5) ^ (key >> 9)); } uint16 miniLEChash(uint16 key) { uint16 h; h = ((((key >> 8) ^ (key & 0xff)) >> 2) & 0xf); if(key >> 9) h = ~h; return (h % 12); } uint8 miniLOMhash(uint16 key) { return ((key >> 4) ^ (key >> 6) ^ (key >> 7)); } uint16 getLECindex(uint16 huff) { uint16 h = HuffIndexLEC[LEChash(huff)]; if((h ^ huff) >> 9) return h & 0x1ff; else return HuffIndexLEC[LECHTab[miniLEChash(huff)]]; } uint16 getLOMindex(uint16 huff) { uint16 h = HuffIndexLOM[LOMhash(huff)]; if((h ^ huff) >> 5) { return h & 0x1f; } else return HuffIndexLOM[LOMHTab[miniLOMhash(huff)]]; } int decompress_rdp(rdpRdp* rdp, uint8* cbuf, int len, int ctype, uint32* roff, uint32* rlen) { int type = ctype & 0x0f; switch (type) { case PACKET_COMPR_TYPE_8K: return decompress_rdp_4(rdp, cbuf, len, ctype, roff, rlen); break; case PACKET_COMPR_TYPE_64K: return decompress_rdp_5(rdp, cbuf, len, ctype, roff, rlen); break; case PACKET_COMPR_TYPE_RDP6: return decompress_rdp_6(rdp, cbuf, len, ctype, roff, rlen); break; case PACKET_COMPR_TYPE_RDP61: return decompress_rdp_61(rdp, cbuf, len, ctype, roff, rlen); break; default: printf("mppc.c: invalid RDP compression code 0x%2.2x\n", type); return false; } } /** * decompress RDP 4 data * * @param rdp per session information * @param cbuf compressed data * @param len length of compressed data * @param ctype compression flags * @param roff starting offset of uncompressed data * @param rlen length of uncompressed data * * @return True on success, False on failure */ int decompress_rdp_4(rdpRdp* rdp, uint8* cbuf, int len, int ctype, uint32* roff, uint32* rlen) { uint8* history_buf; /* uncompressed data goes here */ uint8* history_ptr; /* points to next free slot in history_buf */ uint32 d32; /* we process 4 compressed bytes at a time */ uint16 copy_offset; /* location to copy data from */ uint16 lom; /* length of match */ uint8* src_ptr; /* used while copying compressed data */ uint8* cptr; /* points to next byte in cbuf */ uint8 cur_byte; /* last byte fetched from cbuf */ int bits_left; /* bits left in d34 for processing */ int cur_bits_left; /* bits left in cur_byte for processing */ int tmp; uint32 i32; printf("decompress_rdp_4:\n"); if ((rdp->mppc == NULL) || (rdp->mppc->history_buf == NULL)) { printf("decompress_rdp_4: null\n"); return false; } src_ptr = 0; cptr = cbuf; copy_offset = 0; lom = 0; bits_left = 0; cur_bits_left = 0; d32 = 0; cur_byte = 0; *rlen = 0; /* get start of history buffer */ history_buf = rdp->mppc->history_buf; /* get next free slot in history buffer */ history_ptr = rdp->mppc->history_ptr; *roff = history_ptr - history_buf; if (ctype & PACKET_AT_FRONT) { /* place compressed data at start of history buffer */ history_ptr = rdp->mppc->history_buf; rdp->mppc->history_ptr = rdp->mppc->history_buf; *roff = 0; } if (ctype & PACKET_FLUSHED) { /* re-init history buffer */ history_ptr = rdp->mppc->history_buf; memset(history_buf, 0, RDP6_HISTORY_BUF_SIZE); *roff = 0; } if ((ctype & PACKET_COMPRESSED) != PACKET_COMPRESSED) { /* data in cbuf is not compressed - copy to history buf as is */ memcpy(history_ptr, cbuf, len); history_ptr += len; *rlen = history_ptr - rdp->mppc->history_ptr; rdp->mppc->history_ptr = history_ptr; return true; } /* load initial data */ tmp = 24; while (cptr < cbuf + len) { i32 = *cptr++; d32 |= i32 << tmp; bits_left += 8; tmp -= 8; if (tmp < 0) { break; } } if (cptr < cbuf + len) { cur_byte = *cptr++; cur_bits_left = 8; } else { cur_bits_left = 0; } /* ** start uncompressing data in cbuf */ while (bits_left >= 8) { /* value 0xxxxxxx = literal, not encoded value 10xxxxxx = literal, encoded value 1111xxxx = copy offset 0 - 63 value 1110xxxx = copy offset 64 - 319 value 110xxxxx = copy offset 320 - 8191 */ /* at this point, we are guaranteed that d32 has 32 bits to be processed, unless we have reached end of cbuf */ copy_offset = 0; if ((d32 & 0x80000000) == 0) { /* got a literal */ *history_ptr++ = d32 >> 24; d32 <<= 8; bits_left -= 8; } else if ((d32 & 0xc0000000) == 0x80000000) { /* got encoded literal */ d32 <<= 2; *history_ptr++ = (d32 >> 25) | 0x80; d32 <<= 7; bits_left -= 9; } else if ((d32 & 0xf0000000) == 0xf0000000) { /* got copy offset in range 0 - 63, */ /* with 6 bit copy offset */ d32 <<= 4; copy_offset = d32 >> 26; d32 <<= 6; bits_left -= 10; } else if ((d32 & 0xf0000000) == 0xe0000000) { /* got copy offset in range 64 - 319, */ /* with 8 bit copy offset */ d32 <<= 4; copy_offset = d32 >> 24; copy_offset += 64; d32 <<= 8; bits_left -= 12; } else if ((d32 & 0xe0000000) == 0xc0000000) { /* got copy offset in range 320 - 8191, */ /* with 13 bits copy offset */ d32 <<= 3; copy_offset = d32 >> 19; copy_offset += 320; d32 <<= 13; bits_left -= 16; } /* ** get more bits before we process length of match */ /* how may bits do we need to get? */ tmp = 32 - bits_left; while (tmp) { if (cur_bits_left < tmp) { /* we have less bits than we need */ i32 = cur_byte >> (8 - cur_bits_left); d32 |= i32 << ((32 - bits_left) - cur_bits_left); bits_left += cur_bits_left; tmp -= cur_bits_left; if (cptr < cbuf + len) { /* more compressed data available */ cur_byte = *cptr++; cur_bits_left = 8; } else { /* no more compressed data available */ tmp = 0; cur_bits_left = 0; } } else if (cur_bits_left > tmp) { /* we have more bits than we need */ d32 |= cur_byte >> (8 - tmp); cur_byte <<= tmp; cur_bits_left -= tmp; bits_left = 32; break; } else { /* we have just the right amount of bits */ d32 |= cur_byte >> (8 - tmp); bits_left = 32; if (cptr < cbuf + len) { cur_byte = *cptr++; cur_bits_left = 8; } else { cur_bits_left = 0; } break; } } if (!copy_offset) { continue; } /* ** compute Length of Match */ /* lengh of match Encoding (binary header + LoM bits -------------- ---------------------------------- 3 0 4...7 10 + 2 lower bits of L-o-M 8...15 110 + 3 lower bits of L-o-M 16...31 1110 + 4 lower bits of L-o-M 32...63 11110 + 5 lower bits of L-o-M 64...127 111110 + 6 lower bits of L-o-M 128...255 1111110 + 7 lower bits of L-o-M 256...511 11111110 + 8 lower bits of L-o-M 512...1023 111111110 + 9 lower bits of L-o-M 1024...2047 1111111110 + 10 lower bits of L-o-M 2048...4095 11111111110 + 11 lower bits of L-o-M 4096...8191 111111111110 + 12 lower bits of L-o-M */ if ((d32 & 0x80000000) == 0) { /* lom is fixed to 3 */ lom = 3; d32 <<= 1; bits_left -= 1; } else if ((d32 & 0xc0000000) == 0x80000000) { /* 2 lower bits of LoM */ lom = ((d32 >> 28) & 0x03) + 4; d32 <<= 4; bits_left -= 4; } else if ((d32 & 0xe0000000) == 0xc0000000) { /* 3 lower bits of LoM */ lom = ((d32 >> 26) & 0x07) + 8; d32 <<= 6; bits_left -= 6; } else if ((d32 & 0xf0000000) == 0xe0000000) { /* 4 lower bits of LoM */ lom = ((d32 >> 24) & 0x0f) + 16; d32 <<= 8; bits_left -= 8; } else if ((d32 & 0xf8000000) == 0xf0000000) { /* 5 lower bits of LoM */ lom = ((d32 >> 22) & 0x1f) + 32; d32 <<= 10; bits_left -= 10; } else if ((d32 & 0xfc000000) == 0xf8000000) { /* 6 lower bits of LoM */ lom = ((d32 >> 20) & 0x3f) + 64; d32 <<= 12; bits_left -= 12; } else if ((d32 & 0xfe000000) == 0xfc000000) { /* 7 lower bits of LoM */ lom = ((d32 >> 18) & 0x7f) + 128; d32 <<= 14; bits_left -= 14; } else if ((d32 & 0xff000000) == 0xfe000000) { /* 8 lower bits of LoM */ lom = ((d32 >> 16) & 0xff) + 256; d32 <<= 16; bits_left -= 16; } else if ((d32 & 0xff800000) == 0xff000000) { /* 9 lower bits of LoM */ lom = ((d32 >> 14) & 0x1ff) + 512; d32 <<= 18; bits_left -= 18; } else if ((d32 & 0xffc00000) == 0xff800000) { /* 10 lower bits of LoM */ lom = ((d32 >> 12) & 0x3ff) + 1024; d32 <<= 20; bits_left -= 20; } else if ((d32 & 0xffe00000) == 0xffc00000) { /* 11 lower bits of LoM */ lom = ((d32 >> 10) & 0x7ff) + 2048; d32 <<= 22; bits_left -= 22; } else if ((d32 & 0xfff00000) == 0xffe00000) { /* 12 lower bits of LoM */ lom = ((d32 >> 8) & 0xfff) + 4096; d32 <<= 24; bits_left -= 24; } /* now that we have copy_offset and LoM, process them */ src_ptr = history_ptr - copy_offset; if (src_ptr >= rdp->mppc->history_buf) { /* data does not wrap around */ while (lom > 0) { *history_ptr++ = *src_ptr++; lom--; } } else { src_ptr = rdp->mppc->history_buf_end - (copy_offset - (history_ptr - rdp->mppc->history_buf)); src_ptr++; while (lom && (src_ptr <= rdp->mppc->history_buf_end)) { *history_ptr++ = *src_ptr++; lom--; } src_ptr = rdp->mppc->history_buf; while (lom > 0) { *history_ptr++ = *src_ptr++; lom--; } } /* ** get more bits before we restart the loop */ /* how may bits do we need to get? */ tmp = 32 - bits_left; while (tmp) { if (cur_bits_left < tmp) { /* we have less bits than we need */ i32 = cur_byte >> (8 - cur_bits_left); d32 |= i32 << ((32 - bits_left) - cur_bits_left); bits_left += cur_bits_left; tmp -= cur_bits_left; if (cptr < cbuf + len) { /* more compressed data available */ cur_byte = *cptr++; cur_bits_left = 8; } else { /* no more compressed data available */ tmp = 0; cur_bits_left = 0; } } else if (cur_bits_left > tmp) { /* we have more bits than we need */ d32 |= cur_byte >> (8 - tmp); cur_byte <<= tmp; cur_bits_left -= tmp; bits_left = 32; break; } else { /* we have just the right amount of bits */ d32 |= cur_byte >> (8 - tmp); bits_left = 32; if (cptr < cbuf + len) { cur_byte = *cptr++; cur_bits_left = 8; } else { cur_bits_left = 0; } break; } } } /* end while (bits_left >= 8) */ *rlen = history_ptr - rdp->mppc->history_ptr; rdp->mppc->history_ptr = history_ptr; return true; } /** * decompress RDP 5 data * * @param rdp per session information * @param cbuf compressed data * @param len length of compressed data * @param ctype compression flags * @param roff starting offset of uncompressed data * @param rlen length of uncompressed data * * @return True on success, False on failure */ int decompress_rdp_5(rdpRdp* rdp, uint8* cbuf, int len, int ctype, uint32* roff, uint32* rlen) { uint8* history_buf; /* uncompressed data goes here */ uint8* history_ptr; /* points to next free slot in bistory_buf */ uint32 d32; /* we process 4 compressed bytes at a time */ uint16 copy_offset; /* location to copy data from */ uint16 lom; /* length of match */ uint8* src_ptr; /* used while copying compressed data */ uint8* cptr; /* points to next byte in cbuf */ uint8 cur_byte; /* last byte fetched from cbuf */ int bits_left; /* bits left in d32 for processing */ int cur_bits_left; /* bits left in cur_byte for processing */ int tmp; uint32 i32; if ((rdp->mppc == NULL) || (rdp->mppc->history_buf == NULL)) { printf("decompress_rdp_5: null\n"); return false; } src_ptr = 0; cptr = cbuf; copy_offset = 0; lom = 0; bits_left = 0; cur_bits_left = 0; d32 = 0; cur_byte = 0; *rlen = 0; /* get start of history buffer */ history_buf = rdp->mppc->history_buf; /* get next free slot in history buffer */ history_ptr = rdp->mppc->history_ptr; *roff = history_ptr - history_buf; if (ctype & PACKET_AT_FRONT) { /* place compressed data at start of history buffer */ history_ptr = rdp->mppc->history_buf; rdp->mppc->history_ptr = rdp->mppc->history_buf; *roff = 0; } if (ctype & PACKET_FLUSHED) { /* re-init history buffer */ history_ptr = rdp->mppc->history_buf; memset(history_buf, 0, RDP6_HISTORY_BUF_SIZE); *roff = 0; } if ((ctype & PACKET_COMPRESSED) != PACKET_COMPRESSED) { /* data in cbuf is not compressed - copy to history buf as is */ memcpy(history_ptr, cbuf, len); history_ptr += len; *rlen = history_ptr - rdp->mppc->history_ptr; rdp->mppc->history_ptr = history_ptr; return true; } /* load initial data */ tmp = 24; while (cptr < cbuf + len) { i32 = *cptr++; d32 |= i32 << tmp; bits_left += 8; tmp -= 8; if (tmp < 0) { break; } } if (cptr < cbuf + len) { cur_byte = *cptr++; cur_bits_left = 8; } else { cur_bits_left = 0; } /* ** start uncompressing data in cbuf */ while (bits_left >= 8) { /* value 0xxxxxxx = literal, not encoded value 10xxxxxx = literal, encoded value 11111xxx = copy offset 0 - 63 value 11110xxx = copy offset 64 - 319 value 1110xxxx = copy offset 320 - 2367 value 110xxxxx = copy offset 2368+ */ /* at this point, we are guaranteed that d32 has 32 bits to be processed, unless we have reached end of cbuf */ copy_offset = 0; if ((d32 & 0x80000000) == 0) { /* got a literal */ *history_ptr++ = d32 >> 24; d32 <<= 8; bits_left -= 8; } else if ((d32 & 0xc0000000) == 0x80000000) { /* got encoded literal */ d32 <<= 2; *history_ptr++ = (d32 >> 25) | 0x80; d32 <<= 7; bits_left -= 9; } else if ((d32 & 0xf8000000) == 0xf8000000) { /* got copy offset in range 0 - 63, */ /* with 6 bit copy offset */ d32 <<= 5; copy_offset = d32 >> 26; d32 <<= 6; bits_left -= 11; } else if ((d32 & 0xf8000000) == 0xf0000000) { /* got copy offset in range 64 - 319, */ /* with 8 bit copy offset */ d32 <<= 5; copy_offset = d32 >> 24; copy_offset += 64; d32 <<= 8; bits_left -= 13; } else if ((d32 & 0xf0000000) == 0xe0000000) { /* got copy offset in range 320 - 2367, */ /* with 11 bits copy offset */ d32 <<= 4; copy_offset = d32 >> 21; copy_offset += 320; d32 <<= 11; bits_left -= 15; } else if ((d32 & 0xe0000000) == 0xc0000000) { /* got copy offset in range 2368+, */ /* with 16 bits copy offset */ d32 <<= 3; copy_offset = d32 >> 16; copy_offset += 2368; d32 <<= 16; bits_left -= 19; } /* ** get more bits before we process length of match */ /* how may bits do we need to get? */ tmp = 32 - bits_left; while (tmp) { if (cur_bits_left < tmp) { /* we have less bits than we need */ i32 = cur_byte >> (8 - cur_bits_left); d32 |= i32 << ((32 - bits_left) - cur_bits_left); bits_left += cur_bits_left; tmp -= cur_bits_left; if (cptr < cbuf + len) { /* more compressed data available */ cur_byte = *cptr++; cur_bits_left = 8; } else { /* no more compressed data available */ tmp = 0; cur_bits_left = 0; } } else if (cur_bits_left > tmp) { /* we have more bits than we need */ d32 |= cur_byte >> (8 - tmp); cur_byte <<= tmp; cur_bits_left -= tmp; bits_left = 32; break; } else { /* we have just the right amount of bits */ d32 |= cur_byte >> (8 - tmp); bits_left = 32; if (cptr < cbuf + len) { cur_byte = *cptr++; cur_bits_left = 8; } else { cur_bits_left = 0; } break; } } if (!copy_offset) { continue; } /* ** compute Length of Match */ /* lengh of match Encoding (binary header + LoM bits -------------- ---------------------------------- 3 0 4..7 10 + 2 lower bits of LoM 8..15 110 + 3 lower bits of LoM 16..31 1110 + 4 lower bits of LoM 32..63 1111-0 + 5 lower bits of LoM 64..127 1111-10 + 6 lower bits of LoM 128..255 1111-110 + 7 lower bits of LoM 256..511 1111-1110 + 8 lower bits of LoM 512..1023 1111-1111-0 + 9 lower bits of LoM 1024..2047 1111-1111-10 + 10 lower bits of LoM 2048..4095 1111-1111-110 + 11 lower bits of LoM 4096..8191 1111-1111-1110 + 12 lower bits of LoM 8192..16383 1111-1111-1111-0 + 13 lower bits of LoM 16384..32767 1111-1111-1111-10 + 14 lower bits of LoM 32768..65535 1111-1111-1111-110 + 15 lower bits of LoM */ if ((d32 & 0x80000000) == 0) { /* lom is fixed to 3 */ lom = 3; d32 <<= 1; bits_left -= 1; } else if ((d32 & 0xc0000000) == 0x80000000) { /* 2 lower bits of LoM */ lom = ((d32 >> 28) & 0x03) + 4; d32 <<= 4; bits_left -= 4; } else if ((d32 & 0xe0000000) == 0xc0000000) { /* 3 lower bits of LoM */ lom = ((d32 >> 26) & 0x07) + 8; d32 <<= 6; bits_left -= 6; } else if ((d32 & 0xf0000000) == 0xe0000000) { /* 4 lower bits of LoM */ lom = ((d32 >> 24) & 0x0f) + 16; d32 <<= 8; bits_left -= 8; } else if ((d32 & 0xf8000000) == 0xf0000000) { /* 5 lower bits of LoM */ lom = ((d32 >> 22) & 0x1f) + 32; d32 <<= 10; bits_left -= 10; } else if ((d32 & 0xfc000000) == 0xf8000000) { /* 6 lower bits of LoM */ lom = ((d32 >> 20) & 0x3f) + 64; d32 <<= 12; bits_left -= 12; } else if ((d32 & 0xfe000000) == 0xfc000000) { /* 7 lower bits of LoM */ lom = ((d32 >> 18) & 0x7f) + 128; d32 <<= 14; bits_left -= 14; } else if ((d32 & 0xff000000) == 0xfe000000) { /* 8 lower bits of LoM */ lom = ((d32 >> 16) & 0xff) + 256; d32 <<= 16; bits_left -= 16; } else if ((d32 & 0xff800000) == 0xff000000) { /* 9 lower bits of LoM */ lom = ((d32 >> 14) & 0x1ff) + 512; d32 <<= 18; bits_left -= 18; } else if ((d32 & 0xffc00000) == 0xff800000) { /* 10 lower bits of LoM */ lom = ((d32 >> 12) & 0x3ff) + 1024; d32 <<= 20; bits_left -= 20; } else if ((d32 & 0xffe00000) == 0xffc00000) { /* 11 lower bits of LoM */ lom = ((d32 >> 10) & 0x7ff) + 2048; d32 <<= 22; bits_left -= 22; } else if ((d32 & 0xfff00000) == 0xffe00000) { /* 12 lower bits of LoM */ lom = ((d32 >> 8) & 0xfff) + 4096; d32 <<= 24; bits_left -= 24; } else if ((d32 & 0xfff80000) == 0xfff00000) { /* 13 lower bits of LoM */ lom = ((d32 >> 6) & 0x1fff) + 8192; d32 <<= 26; bits_left -= 26; } else if ((d32 & 0xfffc0000) == 0xfff80000) { /* 14 lower bits of LoM */ lom = ((d32 >> 4) & 0x3fff) + 16384; d32 <<= 28; bits_left -= 28; } else if ((d32 & 0xfffe0000) == 0xfffc0000) { /* 15 lower bits of LoM */ lom = ((d32 >> 2) & 0x7fff) + 32768; d32 <<= 30; bits_left -= 30; } /* now that we have copy_offset and LoM, process them */ src_ptr = history_ptr - copy_offset; if (src_ptr >= rdp->mppc->history_buf) { /* data does not wrap around */ while (lom > 0) { *history_ptr++ = *src_ptr++; lom--; } } else { src_ptr = rdp->mppc->history_buf_end - (copy_offset - (history_ptr - rdp->mppc->history_buf)); src_ptr++; while (lom && (src_ptr <= rdp->mppc->history_buf_end)) { *history_ptr++ = *src_ptr++; lom--; } src_ptr = rdp->mppc->history_buf; while (lom > 0) { *history_ptr++ = *src_ptr++; lom--; } } /* ** get more bits before we restart the loop */ /* how may bits do we need to get? */ tmp = 32 - bits_left; while (tmp) { if (cur_bits_left < tmp) { /* we have less bits than we need */ i32 = cur_byte >> (8 - cur_bits_left); d32 |= i32 << ((32 - bits_left) - cur_bits_left); bits_left += cur_bits_left; tmp -= cur_bits_left; if (cptr < cbuf + len) { /* more compressed data available */ cur_byte = *cptr++; cur_bits_left = 8; } else { /* no more compressed data available */ tmp = 0; cur_bits_left = 0; } } else if (cur_bits_left > tmp) { /* we have more bits than we need */ d32 |= cur_byte >> (8 - tmp); cur_byte <<= tmp; cur_bits_left -= tmp; bits_left = 32; break; } else { /* we have just the right amount of bits */ d32 |= cur_byte >> (8 - tmp); bits_left = 32; if (cptr < cbuf + len) { cur_byte = *cptr++; cur_bits_left = 8; } else { cur_bits_left = 0; } break; } } } /* end while (cptr < cbuf + len) */ *rlen = history_ptr - rdp->mppc->history_ptr; rdp->mppc->history_ptr = history_ptr; return true; } /** * decompress RDP 6 data * * @param rdp per session information * @param cbuf compressed data * @param len length of compressed data * @param ctype compression flags * @param roff starting offset of uncompressed data * @param rlen length of uncompressed data * * @return True on success, False on failure */ int decompress_rdp_6(rdpRdp* rdp, uint8* cbuf, int len, int ctype, uint32* roff, uint32* rlen) { uint8* history_buf; /* uncompressed data goes here */ uint16* offset_cache; /* Copy Offset cache */ uint8* history_ptr; /* points to next free slot in bistory_buf */ uint32 d32; /* we process 4 compressed bytes at a time */ uint16 copy_offset; /* location to copy data from */ uint16 lom; /* length of match */ uint8* src_ptr; /* used while copying compressed data */ uint8* cptr; /* points to next byte in cbuf */ uint8 cur_byte; /* last byte fetched from cbuf */ int bits_left; /* bits left in d32 for processing */ int cur_bits_left; /* bits left in cur_byte for processing */ int tmp; uint32 i32; if ((rdp->mppc == NULL) || (rdp->mppc->history_buf == NULL)) { printf("decompress_rdp_6: null\n"); return false; } src_ptr = 0; cptr = cbuf; copy_offset = 0; lom = 0; bits_left = 0; cur_bits_left = 0; d32 = 0; cur_byte = 0; *rlen = 0; /* get start of history buffer */ history_buf = rdp->mppc->history_buf; /* get start of offset_cache */ offset_cache = rdp->mppc->offset_cache; /* get next free slot in history buffer */ history_ptr = rdp->mppc->history_ptr; *roff = history_ptr - history_buf; if (ctype & PACKET_AT_FRONT) { printf("need to look later\n"); /* slid history_buf and reset history_buf to middle */ memcpy(history_buf, (history_buf + 32768), (history_ptr -history_buf - 32768)); memcpy((history_buf + (history_ptr - history_buf - 32768)), cbuf, len); history_ptr = history_buf + 32768; *roff = 32768; } if (ctype & PACKET_FLUSHED) { /* re-init history buffer */ history_ptr = rdp->mppc->history_buf; memset(history_buf, 0, RDP6_HISTORY_BUF_SIZE); memset(offset_cache, 0, RDP6_OFFSET_CACHE_SIZE); *roff = 0; } if ((ctype & PACKET_COMPRESSED) != PACKET_COMPRESSED) { /* data in cbuf is not compressed - copy to history buf as is */ memcpy(history_ptr, cbuf, len); history_ptr += len; *rlen = history_ptr - rdp->mppc->history_ptr; rdp->mppc->history_ptr = history_ptr; return true; } /* load initial data */ tmp = 24; while (cptr < cbuf + len) { i32 = *cptr++; d32 |= i32 << tmp; bits_left += 8; tmp -= 8; if (tmp < 0) { break; } } if (cptr < cbuf + len) { cur_byte = *cptr++; cur_bits_left = 8; } else { cur_bits_left = 0; } /* ** start uncompressing data in cbuf */ return true; } /** * decompress RDP 6.1 data * * @param rdp per session information * @param cbuf compressed data * @param len length of compressed data * @param ctype compression flags * @param roff starting offset of uncompressed data * @param rlen length of uncompressed data * * @return True on success, False on failure */ int decompress_rdp_61(rdpRdp* rdp, uint8* cbuf, int len, int ctype, uint32* roff, uint32* rlen) { return false; } /** * allocate space to store history buffer * * @param rdp rdp struct that contains rdp_mppc struct * @return pointer to new struct, or NULL on failure */ struct rdp_mppc* mppc_new(rdpRdp* rdp) { struct rdp_mppc* ptr; ptr = (struct rdp_mppc *) xmalloc(sizeof (struct rdp_mppc)); if (!ptr) { printf("mppc_new(): system out of memory\n"); return NULL; } ptr->history_buf = (uint8 *) xmalloc(RDP6_HISTORY_BUF_SIZE); ptr->offset_cache = (uint16 *) xzalloc(RDP6_OFFSET_CACHE_SIZE); if (!ptr->history_buf) { printf("mppc_new(): system out of memory\n"); xfree(ptr); return NULL; } ptr->history_ptr = ptr->history_buf; ptr->history_buf_end = ptr->history_buf + RDP6_HISTORY_BUF_SIZE - 1; return ptr; } /** * free history buffer * * @param rdp rdp struct that contains rdp_mppc struct */ void mppc_free(rdpRdp* rdp) { if (!rdp->mppc) { return; } if (rdp->mppc->history_buf) { xfree(rdp->mppc->history_buf); rdp->mppc->history_buf = NULL; rdp->mppc->history_ptr = NULL; } xfree(rdp->mppc); }