archive-zip.c

   1 /*
   2  * Copyright (c) 2006 Rene Scharfe
   3  */
   4 #include "cache.h"
   5 #include "archive.h"
   6 #include "streaming.h"
   7 #include "utf8.h"
   8
   9 static int zip_date;
  10 static int zip_time;
  11
  12 static unsigned char *zip_dir;
  13 static unsigned int zip_dir_size;
  14
  15 static unsigned int zip_offset;
  16 static unsigned int zip_dir_offset;
  17 static unsigned int zip_dir_entries;
  18
  19 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  20 #define ZIP_STREAM      (1 <<  3)
  21 #define ZIP_UTF8        (1 << 11)
  22
  23 struct zip_local_header {
  24         unsigned char magic[4];
  25         unsigned char version[2];
  26         unsigned char flags[2];
  27         unsigned char compression_method[2];
  28         unsigned char mtime[2];
  29         unsigned char mdate[2];
  30         unsigned char crc32[4];
  31         unsigned char compressed_size[4];
  32         unsigned char size[4];
  33         unsigned char filename_length[2];
  34         unsigned char extra_length[2];
  35         unsigned char _end[1];
  36 };
  37
  38 struct zip_data_desc {
  39         unsigned char magic[4];
  40         unsigned char crc32[4];
  41         unsigned char compressed_size[4];
  42         unsigned char size[4];
  43         unsigned char _end[1];
  44 };
  45
  46 struct zip_dir_header {
  47         unsigned char magic[4];
  48         unsigned char creator_version[2];
  49         unsigned char version[2];
  50         unsigned char flags[2];
  51         unsigned char compression_method[2];
  52         unsigned char mtime[2];
  53         unsigned char mdate[2];
  54         unsigned char crc32[4];
  55         unsigned char compressed_size[4];
  56         unsigned char size[4];
  57         unsigned char filename_length[2];
  58         unsigned char extra_length[2];
  59         unsigned char comment_length[2];
  60         unsigned char disk[2];
  61         unsigned char attr1[2];
  62         unsigned char attr2[4];
  63         unsigned char offset[4];
  64         unsigned char _end[1];
  65 };
  66
  67 struct zip_dir_trailer {
  68         unsigned char magic[4];
  69         unsigned char disk[2];
  70         unsigned char directory_start_disk[2];
  71         unsigned char entries_on_this_disk[2];
  72         unsigned char entries[2];
  73         unsigned char size[4];
  74         unsigned char offset[4];
  75         unsigned char comment_length[2];
  76         unsigned char _end[1];
  77 };
  78
  79 struct zip_extra_mtime {
  80         unsigned char magic[2];
  81         unsigned char extra_size[2];
  82         unsigned char flags[1];
  83         unsigned char mtime[4];
  84         unsigned char _end[1];
  85 };
  86
  87 /*
  88  * On ARM, padding is added at the end of the struct, so a simple
  89  * sizeof(struct ...) reports two bytes more than the payload size
  90  * we're interested in.
  91  */
  92 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  93 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
  94 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  95 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  96 #define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
  97 #define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
  98         (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
  99
 100 static void copy_le16(unsigned char *dest, unsigned int n)
 101 {
 102         dest[0] = 0xff & n;
 103         dest[1] = 0xff & (n >> 010);
 104 }
 105
 106 static void copy_le32(unsigned char *dest, unsigned int n)
 107 {
 108         dest[0] = 0xff & n;
 109         dest[1] = 0xff & (n >> 010);
 110         dest[2] = 0xff & (n >> 020);
 111         dest[3] = 0xff & (n >> 030);
 112 }
 113
 114 static void *zlib_deflate(void *data, unsigned long size,
 115                 int compression_level, unsigned long *compressed_size)
 116 {
 117         git_zstream stream;
 118         unsigned long maxsize;
 119         void *buffer;
 120         int result;
 121
 122         memset(&stream, 0, sizeof(stream));
 123         git_deflate_init(&stream, compression_level);
 124         maxsize = git_deflate_bound(&stream, size);
 125         buffer = xmalloc(maxsize);
 126
 127         stream.next_in = data;
 128         stream.avail_in = size;
 129         stream.next_out = buffer;
 130         stream.avail_out = maxsize;
 131
 132         do {
 133                 result = git_deflate(&stream, Z_FINISH);
 134         } while (result == Z_OK);
 135
 136         if (result != Z_STREAM_END) {
 137                 free(buffer);
 138                 return NULL;
 139         }
 140
 141         git_deflate_end(&stream);
 142         *compressed_size = stream.total_out;
 143
 144         return buffer;
 145 }
 146
 147 static void write_zip_data_desc(unsigned long size,
 148                                 unsigned long compressed_size,
 149                                 unsigned long crc)
 150 {
 151         struct zip_data_desc trailer;
 152
 153         copy_le32(trailer.magic, 0x08074b50);
 154         copy_le32(trailer.crc32, crc);
 155         copy_le32(trailer.compressed_size, compressed_size);
 156         copy_le32(trailer.size, size);
 157         write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 158 }
 159
 160 static void set_zip_dir_data_desc(struct zip_dir_header *header,
 161                                   unsigned long size,
 162                                   unsigned long compressed_size,
 163                                   unsigned long crc)
 164 {
 165         copy_le32(header->crc32, crc);
 166         copy_le32(header->compressed_size, compressed_size);
 167         copy_le32(header->size, size);
 168 }
 169
 170 static void set_zip_header_data_desc(struct zip_local_header *header,
 171                                      unsigned long size,
 172                                      unsigned long compressed_size,
 173                                      unsigned long crc)
 174 {
 175         copy_le32(header->crc32, crc);
 176         copy_le32(header->compressed_size, compressed_size);
 177         copy_le32(header->size, size);
 178 }
 179
 180 static int has_only_ascii(const char *s)
 181 {
 182         for (;;) {
 183                 int c = *s++;
 184                 if (c == '\0')
 185                         return 1;
 186                 if (!isascii(c))
 187                         return 0;
 188         }
 189 }
 190
 191 #define STREAM_BUFFER_SIZE (1024 * 16)
 192
 193 static int write_zip_entry(struct archiver_args *args,
 194                            const unsigned char *sha1,
 195                            const char *path, size_t pathlen,
 196                            unsigned int mode)
 197 {
 198         struct zip_local_header header;
 199         struct zip_dir_header dirent;
 200         struct zip_extra_mtime extra;
 201         unsigned long attr2;
 202         unsigned long compressed_size;
 203         unsigned long crc;
 204         unsigned long direntsize;
 205         int method;
 206         unsigned char *out;
 207         void *deflated = NULL;
 208         void *buffer;
 209         struct git_istream *stream = NULL;
 210         unsigned long flags = 0;
 211         unsigned long size;
 212
 213         crc = crc32(0, NULL, 0);
 214
 215         if (!has_only_ascii(path)) {
 216                 if (is_utf8(path))
 217                         flags |= ZIP_UTF8;
 218                 else
 219                         warning("Path is not valid UTF-8: %s", path);
 220         }
 221
 222         if (pathlen > 0xffff) {
 223                 return error("path too long (%d chars, SHA1: %s): %s",
 224                                 (int)pathlen, sha1_to_hex(sha1), path);
 225         }
 226
 227         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 228                 method = 0;
 229                 attr2 = 16;
 230                 out = NULL;
 231                 size = 0;
 232                 compressed_size = 0;
 233                 buffer = NULL;
 234                 size = 0;
 235         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 236                 enum object_type type = sha1_object_info(sha1, &size);
 237
 238                 method = 0;
 239                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 240                         (mode & 0111) ? ((mode) << 16) : 0;
 241                 if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 242                         method = 8;
 243
 244                 if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
 245                     size > big_file_threshold) {
 246                         stream = open_istream(sha1, &type, &size, NULL);
 247                         if (!stream)
 248                                 return error("cannot stream blob %s",
 249                                              sha1_to_hex(sha1));
 250                         flags |= ZIP_STREAM;
 251                         out = buffer = NULL;
 252                 } else {
 253                         buffer = sha1_file_to_archive(args, path, sha1, mode,
 254                                                       &type, &size);
 255                         if (!buffer)
 256                                 return error("cannot read %s",
 257                                              sha1_to_hex(sha1));
 258                         crc = crc32(crc, buffer, size);
 259                         out = buffer;
 260                 }
 261                 compressed_size = (method == 0) ? size : 0;
 262         } else {
 263                 return error("unsupported file mode: 0%o (SHA1: %s)", mode,
 264                                 sha1_to_hex(sha1));
 265         }
 266
 267         if (buffer && method == 8) {
 268                 deflated = zlib_deflate(buffer, size, args->compression_level,
 269                                 &compressed_size);
 270                 if (deflated && compressed_size - 6 < size) {
 271                         /* ZLIB --> raw compressed data (see RFC 1950) */
 272                         /* CMF and FLG ... */
 273                         out = (unsigned char *)deflated + 2;
 274                         compressed_size -= 6;   /* ... and ADLER32 */
 275                 } else {
 276                         method = 0;
 277                         compressed_size = size;
 278                 }
 279         }
 280
 281         copy_le16(extra.magic, 0x5455);
 282         copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
 283         extra.flags[0] = 1;     /* just mtime */
 284         copy_le32(extra.mtime, args->time);
 285
 286         /* make sure we have enough free space in the dictionary */
 287         direntsize = ZIP_DIR_HEADER_SIZE + pathlen + ZIP_EXTRA_MTIME_SIZE;
 288         while (zip_dir_size < zip_dir_offset + direntsize) {
 289                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 290                 zip_dir = xrealloc(zip_dir, zip_dir_size);
 291         }
 292
 293         copy_le32(dirent.magic, 0x02014b50);
 294         copy_le16(dirent.creator_version,
 295                 S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
 296         copy_le16(dirent.version, 10);
 297         copy_le16(dirent.flags, flags);
 298         copy_le16(dirent.compression_method, method);
 299         copy_le16(dirent.mtime, zip_time);
 300         copy_le16(dirent.mdate, zip_date);
 301         set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 302         copy_le16(dirent.filename_length, pathlen);
 303         copy_le16(dirent.extra_length, ZIP_EXTRA_MTIME_SIZE);
 304         copy_le16(dirent.comment_length, 0);
 305         copy_le16(dirent.disk, 0);
 306         copy_le16(dirent.attr1, 0);
 307         copy_le32(dirent.attr2, attr2);
 308         copy_le32(dirent.offset, zip_offset);
 309
 310         copy_le32(header.magic, 0x04034b50);
 311         copy_le16(header.version, 10);
 312         copy_le16(header.flags, flags);
 313         copy_le16(header.compression_method, method);
 314         copy_le16(header.mtime, zip_time);
 315         copy_le16(header.mdate, zip_date);
 316         set_zip_header_data_desc(&header, size, compressed_size, crc);
 317         copy_le16(header.filename_length, pathlen);
 318         copy_le16(header.extra_length, ZIP_EXTRA_MTIME_SIZE);
 319         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 320         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 321         write_or_die(1, path, pathlen);
 322         zip_offset += pathlen;
 323         write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
 324         zip_offset += ZIP_EXTRA_MTIME_SIZE;
 325         if (stream && method == 0) {
 326                 unsigned char buf[STREAM_BUFFER_SIZE];
 327                 ssize_t readlen;
 328
 329                 for (;;) {
 330                         readlen = read_istream(stream, buf, sizeof(buf));
 331                         if (readlen <= 0)
 332                                 break;
 333                         crc = crc32(crc, buf, readlen);
 334                         write_or_die(1, buf, readlen);
 335                 }
 336                 close_istream(stream);
 337                 if (readlen)
 338                         return readlen;
 339
 340                 compressed_size = size;
 341                 zip_offset += compressed_size;
 342
 343                 write_zip_data_desc(size, compressed_size, crc);
 344                 zip_offset += ZIP_DATA_DESC_SIZE;
 345
 346                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 347         } else if (stream && method == 8) {
 348                 unsigned char buf[STREAM_BUFFER_SIZE];
 349                 ssize_t readlen;
 350                 git_zstream zstream;
 351                 int result;
 352                 size_t out_len;
 353                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 354
 355                 memset(&zstream, 0, sizeof(zstream));
 356                 git_deflate_init(&zstream, args->compression_level);
 357
 358                 compressed_size = 0;
 359                 zstream.next_out = compressed;
 360                 zstream.avail_out = sizeof(compressed);
 361
 362                 for (;;) {
 363                         readlen = read_istream(stream, buf, sizeof(buf));
 364                         if (readlen <= 0)
 365                                 break;
 366                         crc = crc32(crc, buf, readlen);
 367
 368                         zstream.next_in = buf;
 369                         zstream.avail_in = readlen;
 370                         result = git_deflate(&zstream, 0);
 371                         if (result != Z_OK)
 372                                 die("deflate error (%d)", result);
 373                         out = compressed;
 374                         if (!compressed_size)
 375                                 out += 2;
 376                         out_len = zstream.next_out - out;
 377
 378                         if (out_len > 0) {
 379                                 write_or_die(1, out, out_len);
 380                                 compressed_size += out_len;
 381                                 zstream.next_out = compressed;
 382                                 zstream.avail_out = sizeof(compressed);
 383                         }
 384
 385                 }
 386                 close_istream(stream);
 387                 if (readlen)
 388                         return readlen;
 389
 390                 zstream.next_in = buf;
 391                 zstream.avail_in = 0;
 392                 result = git_deflate(&zstream, Z_FINISH);
 393                 if (result != Z_STREAM_END)
 394                         die("deflate error (%d)", result);
 395
 396                 git_deflate_end(&zstream);
 397                 out = compressed;
 398                 if (!compressed_size)
 399                         out += 2;
 400                 out_len = zstream.next_out - out - 4;
 401                 write_or_die(1, out, out_len);
 402                 compressed_size += out_len;
 403                 zip_offset += compressed_size;
 404
 405                 write_zip_data_desc(size, compressed_size, crc);
 406                 zip_offset += ZIP_DATA_DESC_SIZE;
 407
 408                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 409         } else if (compressed_size > 0) {
 410                 write_or_die(1, out, compressed_size);
 411                 zip_offset += compressed_size;
 412         }
 413
 414         free(deflated);
 415         free(buffer);
 416
 417         memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
 418         zip_dir_offset += ZIP_DIR_HEADER_SIZE;
 419         memcpy(zip_dir + zip_dir_offset, path, pathlen);
 420         zip_dir_offset += pathlen;
 421         memcpy(zip_dir + zip_dir_offset, &extra, ZIP_EXTRA_MTIME_SIZE);
 422         zip_dir_offset += ZIP_EXTRA_MTIME_SIZE;
 423         zip_dir_entries++;
 424
 425         return 0;
 426 }
 427
 428 static void write_zip_trailer(const unsigned char *sha1)
 429 {
 430         struct zip_dir_trailer trailer;
 431
 432         copy_le32(trailer.magic, 0x06054b50);
 433         copy_le16(trailer.disk, 0);
 434         copy_le16(trailer.directory_start_disk, 0);
 435         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 436         copy_le16(trailer.entries, zip_dir_entries);
 437         copy_le32(trailer.size, zip_dir_offset);
 438         copy_le32(trailer.offset, zip_offset);
 439         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 440
 441         write_or_die(1, zip_dir, zip_dir_offset);
 442         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 443         if (sha1)
 444                 write_or_die(1, sha1_to_hex(sha1), 40);
 445 }
 446
 447 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 448 {
 449         struct tm *t = localtime(time);
 450
 451         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 452                     (t->tm_year + 1900 - 1980) * 512;
 453         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 454 }
 455
 456 static int write_zip_archive(const struct archiver *ar,
 457                              struct archiver_args *args)
 458 {
 459         int err;
 460
 461         dos_time(&args->time, &zip_date, &zip_time);
 462
 463         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 464         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 465
 466         err = write_archive_entries(args, write_zip_entry);
 467         if (!err)
 468                 write_zip_trailer(args->commit_sha1);
 469
 470         free(zip_dir);
 471
 472         return err;
 473 }
 474
 475 static struct archiver zip_archiver = {
 476         "zip",
 477         write_zip_archive,
 478         ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 479 };
 480
 481 void init_zip_archiver(void)
 482 {
 483         register_archiver(&zip_archiver);
 484 }