1 /*- 2 * Copyright (c) 2009-2011 Sean Purcell 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include "archive_platform.h" 27 28 #ifdef HAVE_ERRNO_H 29 #include <errno.h> 30 #endif 31 32 #ifdef HAVE_ERRNO_H 33 #include <errno.h> 34 #endif 35 #include <stdio.h> 36 #ifdef HAVE_STDLIB_H 37 #include <stdlib.h> 38 #endif 39 #ifdef HAVE_STRING_H 40 #include <string.h> 41 #endif 42 #ifdef HAVE_UNISTD_H 43 #include <unistd.h> 44 #endif 45 #if HAVE_ZSTD_H 46 #include <zstd.h> 47 #endif 48 49 #include "archive.h" 50 #include "archive_endian.h" 51 #include "archive_private.h" 52 #include "archive_read_private.h" 53 54 #if HAVE_ZSTD_H && HAVE_LIBZSTD 55 56 struct private_data { 57 ZSTD_DStream *dstream; 58 unsigned char *out_block; 59 size_t out_block_size; 60 int64_t total_out; 61 char in_frame; /* True = in the middle of a zstd frame. */ 62 char eof; /* True = found end of compressed data. */ 63 }; 64 65 /* Zstd Filter. */ 66 static ssize_t zstd_filter_read(struct archive_read_filter *, const void**); 67 static int zstd_filter_close(struct archive_read_filter *); 68 #endif 69 70 /* 71 * Note that we can detect zstd compressed files even if we can't decompress 72 * them. (In fact, we like detecting them because we can give better error 73 * messages.) So the bid framework here gets compiled even if no zstd library 74 * is available. 75 */ 76 static int zstd_bidder_bid(struct archive_read_filter_bidder *, 77 struct archive_read_filter *); 78 static int zstd_bidder_init(struct archive_read_filter *); 79 80 static const struct archive_read_filter_bidder_vtable 81 zstd_bidder_vtable = { 82 .bid = zstd_bidder_bid, 83 .init = zstd_bidder_init, 84 }; 85 86 int 87 archive_read_support_filter_zstd(struct archive *_a) 88 { 89 struct archive_read *a = (struct archive_read *)_a; 90 91 if (__archive_read_register_bidder(a, NULL, "zstd", 92 &zstd_bidder_vtable) != ARCHIVE_OK) 93 return (ARCHIVE_FATAL); 94 95 #if HAVE_ZSTD_H && HAVE_LIBZSTD 96 return (ARCHIVE_OK); 97 #else 98 archive_set_error(_a, ARCHIVE_ERRNO_MISC, 99 "Using external zstd program for zstd decompression"); 100 return (ARCHIVE_WARN); 101 #endif 102 } 103 104 /* 105 * Test whether we can handle this data. 106 */ 107 static int 108 zstd_bidder_bid(struct archive_read_filter_bidder *self, 109 struct archive_read_filter *filter) 110 { 111 const unsigned char *buffer; 112 ssize_t avail; 113 unsigned prefix; 114 115 /* Zstd frame magic values */ 116 unsigned zstd_magic = 0xFD2FB528U; 117 unsigned zstd_magic_skippable_start = 0x184D2A50U; 118 unsigned zstd_magic_skippable_mask = 0xFFFFFFF0; 119 120 (void) self; /* UNUSED */ 121 122 buffer = __archive_read_filter_ahead(filter, 4, &avail); 123 if (buffer == NULL) 124 return (0); 125 126 prefix = archive_le32dec(buffer); 127 if (prefix == zstd_magic) 128 return (32); 129 if ((prefix & zstd_magic_skippable_mask) == zstd_magic_skippable_start) 130 return (32); 131 132 return (0); 133 } 134 135 #if !(HAVE_ZSTD_H && HAVE_LIBZSTD) 136 137 /* 138 * If we don't have the library on this system, we can't do the 139 * decompression directly. We can, however, try to run "zstd -d" 140 * in case that's available. 141 */ 142 static int 143 zstd_bidder_init(struct archive_read_filter *self) 144 { 145 int r; 146 147 r = __archive_read_program(self, "zstd -d -qq"); 148 /* Note: We set the format here even if __archive_read_program() 149 * above fails. We do, after all, know what the format is 150 * even if we weren't able to read it. */ 151 self->code = ARCHIVE_FILTER_ZSTD; 152 self->name = "zstd"; 153 return (r); 154 } 155 156 #else 157 158 static const struct archive_read_filter_vtable 159 zstd_reader_vtable = { 160 .read = zstd_filter_read, 161 .close = zstd_filter_close, 162 }; 163 164 /* 165 * Initialize the filter object 166 */ 167 static int 168 zstd_bidder_init(struct archive_read_filter *self) 169 { 170 struct private_data *state; 171 size_t out_block_size = ZSTD_DStreamOutSize(); 172 void *out_block; 173 ZSTD_DStream *dstream; 174 175 self->code = ARCHIVE_FILTER_ZSTD; 176 self->name = "zstd"; 177 178 state = (struct private_data *)calloc(1, sizeof(*state)); 179 out_block = (unsigned char *)malloc(out_block_size); 180 dstream = ZSTD_createDStream(); 181 182 if (state == NULL || out_block == NULL || dstream == NULL) { 183 free(out_block); 184 free(state); 185 ZSTD_freeDStream(dstream); /* supports free on NULL */ 186 archive_set_error(&self->archive->archive, ENOMEM, 187 "Can't allocate data for zstd decompression"); 188 return (ARCHIVE_FATAL); 189 } 190 191 self->data = state; 192 193 state->out_block_size = out_block_size; 194 state->out_block = out_block; 195 state->dstream = dstream; 196 self->vtable = &zstd_reader_vtable; 197 198 state->eof = 0; 199 state->in_frame = 0; 200 201 return (ARCHIVE_OK); 202 } 203 204 static ssize_t 205 zstd_filter_read(struct archive_read_filter *self, const void **p) 206 { 207 struct private_data *state; 208 size_t decompressed; 209 ssize_t avail_in; 210 ZSTD_outBuffer out; 211 ZSTD_inBuffer in; 212 size_t ret; 213 214 state = (struct private_data *)self->data; 215 216 out = (ZSTD_outBuffer) { state->out_block, state->out_block_size, 0 }; 217 218 /* Try to fill the output buffer. */ 219 while (out.pos < out.size && !state->eof) { 220 if (!state->in_frame) { 221 ret = ZSTD_initDStream(state->dstream); 222 if (ZSTD_isError(ret)) { 223 archive_set_error(&self->archive->archive, 224 ARCHIVE_ERRNO_MISC, 225 "Error initializing zstd decompressor: %s", 226 ZSTD_getErrorName(ret)); 227 return (ARCHIVE_FATAL); 228 } 229 } 230 in.src = __archive_read_filter_ahead(self->upstream, 1, 231 &avail_in); 232 if (avail_in < 0) { 233 return avail_in; 234 } 235 if (in.src == NULL && avail_in == 0) { 236 if (!state->in_frame) { 237 /* end of stream */ 238 state->eof = 1; 239 break; 240 } else { 241 archive_set_error(&self->archive->archive, 242 ARCHIVE_ERRNO_MISC, 243 "Truncated zstd input"); 244 return (ARCHIVE_FATAL); 245 } 246 } 247 in.size = avail_in; 248 in.pos = 0; 249 250 { 251 ret = ZSTD_decompressStream(state->dstream, &out, &in); 252 253 if (ZSTD_isError(ret)) { 254 archive_set_error(&self->archive->archive, 255 ARCHIVE_ERRNO_MISC, 256 "Zstd decompression failed: %s", 257 ZSTD_getErrorName(ret)); 258 return (ARCHIVE_FATAL); 259 } 260 261 /* Decompressor made some progress */ 262 __archive_read_filter_consume(self->upstream, in.pos); 263 264 /* ret guaranteed to be > 0 if frame isn't done yet */ 265 state->in_frame = (ret != 0); 266 } 267 } 268 269 decompressed = out.pos; 270 state->total_out += decompressed; 271 if (decompressed == 0) 272 *p = NULL; 273 else 274 *p = state->out_block; 275 return (decompressed); 276 } 277 278 /* 279 * Clean up the decompressor. 280 */ 281 static int 282 zstd_filter_close(struct archive_read_filter *self) 283 { 284 struct private_data *state; 285 286 state = (struct private_data *)self->data; 287 288 ZSTD_freeDStream(state->dstream); 289 free(state->out_block); 290 free(state); 291 292 return (ARCHIVE_OK); 293 } 294 295 #endif /* HAVE_ZLIB_H && HAVE_LIBZSTD */ 296