1 /* $NetBSD: unxz.c,v 1.7 2017/08/04 07:27:08 mrg Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-2-Clause-NetBSD 5 * 6 * Copyright (c) 2011 The NetBSD Foundation, Inc. 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to The NetBSD Foundation 10 * by Christos Zoulas. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include <stdarg.h> 37 #include <errno.h> 38 #include <stdio.h> 39 #include <unistd.h> 40 #include <lzma.h> 41 42 static off_t 43 unxz(int i, int o, char *pre, size_t prelen, off_t *bytes_in) 44 { 45 lzma_stream strm = LZMA_STREAM_INIT; 46 static const int flags = LZMA_TELL_UNSUPPORTED_CHECK|LZMA_CONCATENATED; 47 lzma_ret ret; 48 lzma_action action = LZMA_RUN; 49 off_t bytes_out, bp; 50 uint8_t ibuf[BUFSIZ]; 51 uint8_t obuf[BUFSIZ]; 52 53 if (bytes_in == NULL) 54 bytes_in = &bp; 55 56 strm.next_in = ibuf; 57 memcpy(ibuf, pre, prelen); 58 strm.avail_in = read(i, ibuf + prelen, sizeof(ibuf) - prelen); 59 if (strm.avail_in == (size_t)-1) 60 maybe_err("read failed"); 61 infile_newdata(strm.avail_in); 62 strm.avail_in += prelen; 63 *bytes_in = strm.avail_in; 64 65 if ((ret = lzma_stream_decoder(&strm, UINT64_MAX, flags)) != LZMA_OK) 66 maybe_errx("Can't initialize decoder (%d)", ret); 67 68 strm.next_out = NULL; 69 strm.avail_out = 0; 70 if ((ret = lzma_code(&strm, LZMA_RUN)) != LZMA_OK) 71 maybe_errx("Can't read headers (%d)", ret); 72 73 bytes_out = 0; 74 strm.next_out = obuf; 75 strm.avail_out = sizeof(obuf); 76 77 for (;;) { 78 check_siginfo(); 79 if (strm.avail_in == 0) { 80 strm.next_in = ibuf; 81 strm.avail_in = read(i, ibuf, sizeof(ibuf)); 82 switch (strm.avail_in) { 83 case (size_t)-1: 84 maybe_err("read failed"); 85 /*NOTREACHED*/ 86 case 0: 87 action = LZMA_FINISH; 88 break; 89 default: 90 infile_newdata(strm.avail_in); 91 *bytes_in += strm.avail_in; 92 break; 93 } 94 } 95 96 ret = lzma_code(&strm, action); 97 98 // Write and check write error before checking decoder error. 99 // This way as much data as possible gets written to output 100 // even if decoder detected an error. 101 if (strm.avail_out == 0 || ret != LZMA_OK) { 102 const size_t write_size = sizeof(obuf) - strm.avail_out; 103 104 if (write(o, obuf, write_size) != (ssize_t)write_size) 105 maybe_err("write failed"); 106 107 strm.next_out = obuf; 108 strm.avail_out = sizeof(obuf); 109 bytes_out += write_size; 110 } 111 112 if (ret != LZMA_OK) { 113 if (ret == LZMA_STREAM_END) { 114 // Check that there's no trailing garbage. 115 if (strm.avail_in != 0 || read(i, ibuf, 1)) 116 ret = LZMA_DATA_ERROR; 117 else { 118 lzma_end(&strm); 119 return bytes_out; 120 } 121 } 122 123 const char *msg; 124 switch (ret) { 125 case LZMA_MEM_ERROR: 126 msg = strerror(ENOMEM); 127 break; 128 129 case LZMA_FORMAT_ERROR: 130 msg = "File format not recognized"; 131 break; 132 133 case LZMA_OPTIONS_ERROR: 134 // FIXME: Better message? 135 msg = "Unsupported compression options"; 136 break; 137 138 case LZMA_DATA_ERROR: 139 msg = "File is corrupt"; 140 break; 141 142 case LZMA_BUF_ERROR: 143 msg = "Unexpected end of input"; 144 break; 145 146 case LZMA_MEMLIMIT_ERROR: 147 msg = "Reached memory limit"; 148 break; 149 150 default: 151 maybe_errx("Unknown error (%d)", ret); 152 break; 153 } 154 maybe_errx("%s", msg); 155 156 } 157 } 158 } 159