1 /* $OpenBSD: ntfs_compr.c,v 1.7 2013/11/24 16:02:30 jsing Exp $ */ 2 /* $NetBSD: ntfs_compr.c,v 1.1 2002/12/23 17:38:31 jdolecek Exp $ */ 3 4 /*- 5 * Copyright (c) 1998, 1999 Semen Ustimenko 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * Id: ntfs_compr.c,v 1.4 1999/05/12 09:42:54 semenu Exp 30 */ 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/mount.h> 35 36 #include <ntfs/ntfs.h> 37 #include <ntfs/ntfs_compr.h> 38 39 #define GET_UINT16(addr) (*((u_int16_t *)(addr))) 40 41 int 42 ntfs_uncompblock(u_int8_t *buf, u_int8_t *cbuf) 43 { 44 u_int32_t ctag; 45 int len, dshift, lmask; 46 int blen, boff; 47 int i, j; 48 int pos, cpos; 49 50 len = GET_UINT16(cbuf) & 0xFFF; 51 DPRINTF("ntfs_uncompblock: block length: %d + 3, 0x%x,0x%04x\n", 52 len, len, GET_UINT16(cbuf)); 53 54 if (!(GET_UINT16(cbuf) & 0x8000)) { 55 if ((len + 1) != NTFS_COMPBLOCK_SIZE) { 56 DPRINTF("ntfs_uncompblock: len: %x instead of %d\n", 57 len, 0xfff); 58 } 59 memcpy(buf, cbuf + 2, len + 1); 60 bzero(buf + len + 1, NTFS_COMPBLOCK_SIZE - 1 - len); 61 return (len + 3); 62 } 63 cpos = 2; 64 pos = 0; 65 while ((cpos < len + 3) && (pos < NTFS_COMPBLOCK_SIZE)) { 66 ctag = cbuf[cpos++]; 67 for (i = 0; (i < 8) && (pos < NTFS_COMPBLOCK_SIZE); i++) { 68 if (ctag & 1) { 69 for (j = pos - 1, lmask = 0xFFF, dshift = 12; 70 j >= 0x10; j >>= 1) { 71 dshift--; 72 lmask >>= 1; 73 } 74 boff = -1 - (GET_UINT16(cbuf + cpos) >> dshift); 75 blen = 3 + (GET_UINT16(cbuf + cpos) & lmask); 76 for (j = 0; (j < blen) && 77 (pos < NTFS_COMPBLOCK_SIZE); j++) { 78 buf[pos] = buf[pos + boff]; 79 pos++; 80 } 81 cpos += 2; 82 } else { 83 buf[pos++] = cbuf[cpos++]; 84 } 85 ctag >>= 1; 86 } 87 } 88 return (len + 3); 89 } 90 91 int 92 ntfs_uncompunit(struct ntfsmount *ntmp, u_int8_t *uup, u_int8_t *cup) 93 { 94 int i; 95 int off = 0; 96 int new; 97 98 for (i = 0; i * NTFS_COMPBLOCK_SIZE < ntfs_cntob(NTFS_COMPUNIT_CL); 99 i++) { 100 new = ntfs_uncompblock(uup + i * NTFS_COMPBLOCK_SIZE, 101 cup + off); 102 if (new == 0) 103 return (EINVAL); 104 off += new; 105 } 106 return (0); 107 } 108