1/* vi: set sw=4 ts=4: */ 2/* 3 * Mini unzip implementation for busybox 4 * 5 * Copyright (C) 2004 by Ed Clark 6 * 7 * Loosely based on original busybox unzip applet by Laurence Anderson. 8 * All options and features should work in this version. 9 * 10 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. 11 */ 12 13/* For reference see 14 * http://www.pkware.com/company/standards/appnote/ 15 * http://www.info-zip.org/pub/infozip/doc/appnote-iz-latest.zip 16 */ 17 18/* TODO 19 * Endian issues 20 * Zip64 + other methods 21 * Improve handling of zip format, ie. 22 * - deferred CRC, comp. & uncomp. lengths (zip header flags bit 3) 23 * - unix file permissions, etc. 24 * - central directory 25 */ 26 27#include "libbb.h" 28#include "unarchive.h" 29 30#define ZIP_FILEHEADER_MAGIC SWAP_LE32(0x04034b50) 31#define ZIP_CDS_MAGIC SWAP_LE32(0x02014b50) 32#define ZIP_CDS_END_MAGIC SWAP_LE32(0x06054b50) 33#define ZIP_DD_MAGIC SWAP_LE32(0x08074b50) 34 35typedef union { 36 unsigned char raw[26]; 37 struct { 38 unsigned short version; /* 0-1 */ 39 unsigned short flags; /* 2-3 */ 40 unsigned short method; /* 4-5 */ 41 unsigned short modtime; /* 6-7 */ 42 unsigned short moddate; /* 8-9 */ 43 unsigned int crc32 ATTRIBUTE_PACKED; /* 10-13 */ 44 unsigned int cmpsize ATTRIBUTE_PACKED; /* 14-17 */ 45 unsigned int ucmpsize ATTRIBUTE_PACKED; /* 18-21 */ 46 unsigned short filename_len; /* 22-23 */ 47 unsigned short extra_len; /* 24-25 */ 48 } formatted ATTRIBUTE_PACKED; 49} zip_header_t; 50 51static void unzip_skip(int fd, off_t skip) 52{ 53 if (lseek(fd, skip, SEEK_CUR) == (off_t)-1) { 54 if (errno != ESPIPE) 55 bb_error_msg_and_die("seek failure"); 56 bb_copyfd_exact_size(fd, -1, skip); 57 } 58} 59 60static void unzip_create_leading_dirs(char *fn) 61{ 62 /* Create all leading directories */ 63 char *name = xstrdup(fn); 64 if (bb_make_directory(dirname(name), 0777, FILEUTILS_RECUR)) { 65 bb_error_msg_and_die("exiting"); /* bb_make_directory is noisy */ 66 } 67 free(name); 68} 69 70static int unzip_extract(zip_header_t *zip_header, int src_fd, int dst_fd) 71{ 72 if (zip_header->formatted.method == 0) { 73 /* Method 0 - stored (not compressed) */ 74 off_t size = zip_header->formatted.ucmpsize; 75 if (size) 76 bb_copyfd_exact_size(src_fd, dst_fd, size); 77 } else { 78 /* Method 8 - inflate */ 79 inflate_unzip_result res; 80 /* err = */ inflate_unzip(&res, zip_header->formatted.cmpsize, src_fd, dst_fd); 81// we should check for -1 error return 82 /* Validate decompression - crc */ 83 if (zip_header->formatted.crc32 != (res.crc ^ 0xffffffffL)) { 84 bb_error_msg("invalid compressed data--%s error", "crc"); 85 return 1; 86 } 87 /* Validate decompression - size */ 88 if (zip_header->formatted.ucmpsize != res.bytes_out) { 89 bb_error_msg("invalid compressed data--%s error", "length"); 90 return 1; 91 } 92 } 93 return 0; 94} 95 96int unzip_main(int argc, char **argv); 97int unzip_main(int argc, char **argv) 98{ 99 zip_header_t zip_header; 100 enum {v_silent, v_normal, v_list} verbosity = v_normal; 101 enum {o_prompt, o_never, o_always} overwrite = o_prompt; 102 unsigned int total_size = 0; 103 unsigned int total_entries = 0; 104 int src_fd = -1, dst_fd = -1; 105 char *src_fn = NULL, *dst_fn = NULL; 106 llist_t *zaccept = NULL; 107 llist_t *zreject = NULL; 108 char *base_dir = NULL; 109 int failed, i, opt, opt_range = 0, list_header_done = 0; 110 char key_buf[512]; 111 struct stat stat_buf; 112 113 while ((opt = getopt(argc, argv, "-d:lnopqx")) != -1) { 114 switch (opt_range) { 115 case 0: /* Options */ 116 switch (opt) { 117 case 'l': /* List */ 118 verbosity = v_list; 119 break; 120 121 case 'n': /* Never overwrite existing files */ 122 overwrite = o_never; 123 break; 124 125 case 'o': /* Always overwrite existing files */ 126 overwrite = o_always; 127 break; 128 129 case 'p': /* Extract files to stdout and fall through to set verbosity */ 130 dst_fd = STDOUT_FILENO; 131 132 case 'q': /* Be quiet */ 133 verbosity = (verbosity == v_normal) ? v_silent : verbosity; 134 break; 135 136 case 1 : /* The zip file */ 137 src_fn = xmalloc(strlen(optarg)+4); 138 strcpy(src_fn, optarg); 139 opt_range++; 140 break; 141 142 default: 143 bb_show_usage(); 144 145 } 146 break; 147 148 case 1: /* Include files */ 149 if (opt == 1) { 150 llist_add_to(&zaccept, optarg); 151 152 } else if (opt == 'd') { 153 base_dir = optarg; 154 opt_range += 2; 155 156 } else if (opt == 'x') { 157 opt_range++; 158 159 } else { 160 bb_show_usage(); 161 } 162 break; 163 164 case 2 : /* Exclude files */ 165 if (opt == 1) { 166 llist_add_to(&zreject, optarg); 167 168 } else if (opt == 'd') { /* Extract to base directory */ 169 base_dir = optarg; 170 opt_range++; 171 172 } else { 173 bb_show_usage(); 174 } 175 break; 176 177 default: 178 bb_show_usage(); 179 } 180 } 181 182 if (src_fn == NULL) { 183 bb_show_usage(); 184 } 185 186 /* Open input file */ 187 if (LONE_DASH(src_fn)) { 188 src_fd = STDIN_FILENO; 189 /* Cannot use prompt mode since zip data is arriving on STDIN */ 190 overwrite = (overwrite == o_prompt) ? o_never : overwrite; 191 } else { 192 static const char *const extn[] = {"", ".zip", ".ZIP"}; 193 int orig_src_fn_len = strlen(src_fn); 194 for (i = 0; (i < 3) && (src_fd == -1); i++) { 195 strcpy(src_fn + orig_src_fn_len, extn[i]); 196 src_fd = open(src_fn, O_RDONLY); 197 } 198 if (src_fd == -1) { 199 src_fn[orig_src_fn_len] = '\0'; 200 bb_error_msg_and_die("cannot open %s, %s.zip, %s.ZIP", src_fn, src_fn, src_fn); 201 } 202 } 203 204 /* Change dir if necessary */ 205 if (base_dir) 206 xchdir(base_dir); 207 208 if (verbosity != v_silent) 209 printf("Archive: %s\n", src_fn); 210 211 failed = 0; 212 213 while (1) { 214 unsigned int magic; 215 216 /* Check magic number */ 217 xread(src_fd, &magic, 4); 218 if (magic == ZIP_CDS_MAGIC) { 219 break; 220 } else if (magic != ZIP_FILEHEADER_MAGIC) { 221 bb_error_msg_and_die("invalid zip magic %08X", magic); 222 } 223 224 /* Read the file header */ 225 xread(src_fd, zip_header.raw, 26); 226 zip_header.formatted.version = SWAP_LE32(zip_header.formatted.version); 227 zip_header.formatted.flags = SWAP_LE32(zip_header.formatted.flags); 228 zip_header.formatted.method = SWAP_LE32(zip_header.formatted.method); 229 zip_header.formatted.modtime = SWAP_LE32(zip_header.formatted.modtime); 230 zip_header.formatted.moddate = SWAP_LE32(zip_header.formatted.moddate); 231 zip_header.formatted.crc32 = SWAP_LE32(zip_header.formatted.crc32); 232 zip_header.formatted.cmpsize = SWAP_LE32(zip_header.formatted.cmpsize); 233 zip_header.formatted.ucmpsize = SWAP_LE32(zip_header.formatted.ucmpsize); 234 zip_header.formatted.filename_len = SWAP_LE32(zip_header.formatted.filename_len); 235 zip_header.formatted.extra_len = SWAP_LE32(zip_header.formatted.extra_len); 236 if ((zip_header.formatted.method != 0) && (zip_header.formatted.method != 8)) { 237 bb_error_msg_and_die("unsupported compression method %d", zip_header.formatted.method); 238 } 239 240 /* Read filename */ 241 free(dst_fn); 242 dst_fn = xzalloc(zip_header.formatted.filename_len + 1); 243 xread(src_fd, dst_fn, zip_header.formatted.filename_len); 244 245 /* Skip extra header bytes */ 246 unzip_skip(src_fd, zip_header.formatted.extra_len); 247 248 if ((verbosity == v_list) && !list_header_done){ 249 puts(" Length Date Time Name\n" 250 " -------- ---- ---- ----"); 251 list_header_done = 1; 252 } 253 254 /* Filter zip entries */ 255 if (find_list_entry(zreject, dst_fn) || 256 (zaccept && !find_list_entry(zaccept, dst_fn))) { /* Skip entry */ 257 i = 'n'; 258 259 } else { /* Extract entry */ 260 total_size += zip_header.formatted.ucmpsize; 261 262 if (verbosity == v_list) { /* List entry */ 263 unsigned int dostime = zip_header.formatted.modtime | (zip_header.formatted.moddate << 16); 264 printf("%9u %02u-%02u-%02u %02u:%02u %s\n", 265 zip_header.formatted.ucmpsize, 266 (dostime & 0x01e00000) >> 21, 267 (dostime & 0x001f0000) >> 16, 268 (((dostime & 0xfe000000) >> 25) + 1980) % 100, 269 (dostime & 0x0000f800) >> 11, 270 (dostime & 0x000007e0) >> 5, 271 dst_fn); 272 total_entries++; 273 i = 'n'; 274 } else if (dst_fd == STDOUT_FILENO) { /* Extracting to STDOUT */ 275 i = -1; 276 } else if (last_char_is(dst_fn, '/')) { /* Extract directory */ 277 if (stat(dst_fn, &stat_buf) == -1) { 278 if (errno != ENOENT) { 279 bb_perror_msg_and_die("cannot stat '%s'",dst_fn); 280 } 281 if (verbosity == v_normal) { 282 printf(" creating: %s\n", dst_fn); 283 } 284 unzip_create_leading_dirs(dst_fn); 285 if (bb_make_directory(dst_fn, 0777, 0)) { 286 bb_error_msg_and_die("exiting"); 287 } 288 } else { 289 if (!S_ISDIR(stat_buf.st_mode)) { 290 bb_error_msg_and_die("'%s' exists but is not directory", dst_fn); 291 } 292 } 293 i = 'n'; 294 295 } else { /* Extract file */ 296 _check_file: 297 if (stat(dst_fn, &stat_buf) == -1) { /* File does not exist */ 298 if (errno != ENOENT) { 299 bb_perror_msg_and_die("cannot stat '%s'",dst_fn); 300 } 301 i = 'y'; 302 } else { /* File already exists */ 303 if (overwrite == o_never) { 304 i = 'n'; 305 } else if (S_ISREG(stat_buf.st_mode)) { /* File is regular file */ 306 if (overwrite == o_always) { 307 i = 'y'; 308 } else { 309 printf("replace %s? [y]es, [n]o, [A]ll, [N]one, [r]ename: ", dst_fn); 310 if (!fgets(key_buf, 512, stdin)) { 311 bb_perror_msg_and_die("cannot read input"); 312 } 313 i = key_buf[0]; 314 } 315 } else { /* File is not regular file */ 316 bb_error_msg_and_die("'%s' exists but is not regular file",dst_fn); 317 } 318 } 319 } 320 } 321 322 switch (i) { 323 case 'A': 324 overwrite = o_always; 325 case 'y': /* Open file and fall into unzip */ 326 unzip_create_leading_dirs(dst_fn); 327 dst_fd = xopen(dst_fn, O_WRONLY | O_CREAT | O_TRUNC); 328 case -1: /* Unzip */ 329 if (verbosity == v_normal) { 330 printf(" inflating: %s\n", dst_fn); 331 } 332 if (unzip_extract(&zip_header, src_fd, dst_fd)) { 333 failed = 1; 334 } 335 if (dst_fd != STDOUT_FILENO) { 336 /* closing STDOUT is potentially bad for future business */ 337 close(dst_fd); 338 } 339 break; 340 341 case 'N': 342 overwrite = o_never; 343 case 'n': 344 /* Skip entry data */ 345 unzip_skip(src_fd, zip_header.formatted.cmpsize); 346 break; 347 348 case 'r': 349 /* Prompt for new name */ 350 printf("new name: "); 351 if (!fgets(key_buf, 512, stdin)) { 352 bb_perror_msg_and_die("cannot read input"); 353 } 354 free(dst_fn); 355 dst_fn = xstrdup(key_buf); 356 chomp(dst_fn); 357 goto _check_file; 358 359 default: 360 printf("error: invalid response [%c]\n",(char)i); 361 goto _check_file; 362 } 363 364 /* Data descriptor section */ 365 if (zip_header.formatted.flags & 4) { 366 /* skip over duplicate crc, compressed size and uncompressed size */ 367 unzip_skip(src_fd, 12); 368 } 369 } 370 371 if (verbosity == v_list) { 372 printf(" -------- -------\n" 373 "%9d %d files\n", total_size, total_entries); 374 } 375 376 return failed; 377} 378