diff options
| -rw-r--r-- | archival/unzip.c | 243 |
1 files changed, 196 insertions, 47 deletions
diff --git a/archival/unzip.c b/archival/unzip.c index 1c9bc24..e468ff4 100644 --- a/archival/unzip.c +++ b/archival/unzip.c @@ -16,12 +16,7 @@ */ /* TODO - * Endian issues * Zip64 + other methods - * Improve handling of zip format, ie. - * - deferred CRC, comp. & uncomp. lengths (zip header flags bit 3) - * - unix file permissions, etc. - * - central directory */ #include "libbb.h" @@ -31,12 +26,12 @@ enum { #if BB_BIG_ENDIAN ZIP_FILEHEADER_MAGIC = 0x504b0304, ZIP_CDS_MAGIC = 0x504b0102, - ZIP_CDS_END_MAGIC = 0x504b0506, + ZIP_CDE_MAGIC = 0x504b0506, ZIP_DD_MAGIC = 0x504b0708, #else ZIP_FILEHEADER_MAGIC = 0x04034b50, ZIP_CDS_MAGIC = 0x02014b50, - ZIP_CDS_END_MAGIC = 0x06054b50, + ZIP_CDE_MAGIC = 0x06054b50, ZIP_DD_MAGIC = 0x08074b50, #endif }; @@ -46,16 +41,16 @@ enum { typedef union { uint8_t raw[ZIP_HEADER_LEN]; struct { - uint16_t version; /* 0-1 */ - uint16_t flags; /* 2-3 */ - uint16_t method; /* 4-5 */ - uint16_t modtime; /* 6-7 */ - uint16_t moddate; /* 8-9 */ - uint32_t crc32 PACKED; /* 10-13 */ - uint32_t cmpsize PACKED; /* 14-17 */ - uint32_t ucmpsize PACKED; /* 18-21 */ - uint16_t filename_len; /* 22-23 */ - uint16_t extra_len; /* 24-25 */ + uint16_t version; /* 0-1 */ + uint16_t flags; /* 2-3 */ + uint16_t method; /* 4-5 */ + uint16_t modtime; /* 6-7 */ + uint16_t moddate; /* 8-9 */ + uint32_t crc32 PACKED; /* 10-13 */ + uint32_t cmpsize PACKED; /* 14-17 */ + uint32_t ucmpsize PACKED; /* 18-21 */ + uint16_t filename_len; /* 22-23 */ + uint16_t extra_len; /* 24-25 */ } formatted PACKED; } zip_header_t; /* PACKED - gcc 4.2.1 doesn't like it (spews warning) */ @@ -65,11 +60,11 @@ typedef union { */ struct BUG_zip_header_must_be_26_bytes { char BUG_zip_header_must_be_26_bytes[ - offsetof(zip_header_t, formatted.extra_len) + 2 == - ZIP_HEADER_LEN ? 1 : -1]; + offsetof(zip_header_t, formatted.extra_len) + 2 + == ZIP_HEADER_LEN ? 1 : -1]; }; -#define FIX_ENDIANNESS(zip_header) do { \ +#define FIX_ENDIANNESS_ZIP(zip_header) do { \ (zip_header).formatted.version = SWAP_LE16((zip_header).formatted.version ); \ (zip_header).formatted.flags = SWAP_LE16((zip_header).formatted.flags ); \ (zip_header).formatted.method = SWAP_LE16((zip_header).formatted.method ); \ @@ -82,9 +77,138 @@ struct BUG_zip_header_must_be_26_bytes { (zip_header).formatted.extra_len = SWAP_LE16((zip_header).formatted.extra_len ); \ } while (0) -static void unzip_skip(int fd, off_t skip) +#define CDS_HEADER_LEN 42 + +typedef union { + uint8_t raw[CDS_HEADER_LEN]; + struct { + /* uint32_t signature; 50 4b 01 02 */ + uint16_t version_made_by; /* 0-1 */ + uint16_t version_needed; /* 2-3 */ + uint16_t cds_flags; /* 4-5 */ + uint16_t method; /* 6-7 */ + uint16_t mtime; /* 8-9 */ + uint16_t mdate; /* 10-11 */ + uint32_t crc32; /* 12-15 */ + uint32_t cmpsize; /* 16-19 */ + uint32_t ucmpsize; /* 20-23 */ + uint16_t file_name_length; /* 24-25 */ + uint16_t extra_field_length; /* 26-27 */ + uint16_t file_comment_length; /* 28-29 */ + uint16_t disk_number_start; /* 30-31 */ + uint16_t internal_file_attributes; /* 32-33 */ + uint32_t external_file_attributes PACKED; /* 34-37 */ + uint32_t relative_offset_of_local_header PACKED; /* 38-41 */ + } formatted PACKED; +} cds_header_t; + +struct BUG_cds_header_must_be_42_bytes { + char BUG_cds_header_must_be_42_bytes[ + offsetof(cds_header_t, formatted.relative_offset_of_local_header) + 4 + == CDS_HEADER_LEN ? 1 : -1]; +}; + +#define FIX_ENDIANNESS_CDS(cds_header) do { \ + (cds_header).formatted.crc32 = SWAP_LE32((cds_header).formatted.crc32 ); \ + (cds_header).formatted.cmpsize = SWAP_LE32((cds_header).formatted.cmpsize ); \ + (cds_header).formatted.ucmpsize = SWAP_LE32((cds_header).formatted.ucmpsize ); \ + (cds_header).formatted.file_name_length = SWAP_LE16((cds_header).formatted.file_name_length); \ + (cds_header).formatted.extra_field_length = SWAP_LE16((cds_header).formatted.extra_field_length); \ + (cds_header).formatted.file_comment_length = SWAP_LE16((cds_header).formatted.file_comment_length); \ +} while (0) + +#define CDE_HEADER_LEN 16 + +typedef union { + uint8_t raw[CDE_HEADER_LEN]; + struct { + /* uint32_t signature; 50 4b 05 06 */ + uint16_t this_disk_no; + uint16_t disk_with_cds_no; + uint16_t cds_entries_on_this_disk; + uint16_t cds_entries_total; + uint32_t cds_size; + uint32_t cds_offset; + /* uint16_t file_comment_length; */ + /* .ZIP file comment (variable size) */ + } formatted PACKED; +} cde_header_t; + +struct BUG_cde_header_must_be_16_bytes { + char BUG_cde_header_must_be_16_bytes[ + sizeof(cde_header_t) == CDE_HEADER_LEN ? 1 : -1]; +}; + +#define FIX_ENDIANNESS_CDE(cde_header) do { \ + (cde_header).formatted.cds_offset = SWAP_LE16((cde_header).formatted.cds_offset); \ +} while (0) + +enum { zip_fd = 3 }; + + +#if ENABLE_DESKTOP +/* NB: does not preserve file position! */ +static uint32_t find_cds_offset(void) +{ + unsigned char buf[1024]; + cde_header_t cde_header; + unsigned char *p; + off_t end; + + end = xlseek(zip_fd, 0, SEEK_END); + if (end < 1024) + end = 1024; + end -= 1024; + xlseek(zip_fd, end, SEEK_SET); + full_read(zip_fd, buf, 1024); + + p = buf; + while (p <= buf + 1024 - CDE_HEADER_LEN - 4) { + if (*p != 'P') { + p++; + continue; + } + if (*++p != 'K') + continue; + if (*++p != 5) + continue; + if (*++p != 6) + continue; + /* we found CDE! */ + memcpy(cde_header.raw, p + 1, CDE_HEADER_LEN); + FIX_ENDIANNESS_CDE(cde_header); + return cde_header.formatted.cds_offset; + } + bb_error_msg_and_die("can't find file table"); +}; + +static uint32_t read_next_cds(int count_m1, uint32_t cds_offset, cds_header_t *cds_ptr) { - bb_copyfd_exact_size(fd, -1, skip); + off_t org; + + org = xlseek(zip_fd, 0, SEEK_CUR); + + if (!cds_offset) + cds_offset = find_cds_offset(); + + while (count_m1-- >= 0) { + xlseek(zip_fd, cds_offset + 4, SEEK_SET); + xread(zip_fd, cds_ptr->raw, CDS_HEADER_LEN); + FIX_ENDIANNESS_CDS(*cds_ptr); + cds_offset += 4 + CDS_HEADER_LEN + + cds_ptr->formatted.file_name_length + + cds_ptr->formatted.extra_field_length + + cds_ptr->formatted.file_comment_length; + } + + xlseek(zip_fd, org, SEEK_SET); + return cds_offset; +}; +#endif + +static void unzip_skip(off_t skip) +{ + bb_copyfd_exact_size(zip_fd, -1, skip); } static void unzip_create_leading_dirs(const char *fn) @@ -97,17 +221,17 @@ static void unzip_create_leading_dirs(const char *fn) free(name); } -static void unzip_extract(zip_header_t *zip_header, int src_fd, int dst_fd) +static void unzip_extract(zip_header_t *zip_header, int dst_fd) { if (zip_header->formatted.method == 0) { /* Method 0 - stored (not compressed) */ off_t size = zip_header->formatted.ucmpsize; if (size) - bb_copyfd_exact_size(src_fd, dst_fd, size); + bb_copyfd_exact_size(zip_fd, dst_fd, size); } else { /* Method 8 - inflate */ inflate_unzip_result res; - if (inflate_unzip(&res, zip_header->formatted.cmpsize, src_fd, dst_fd) < 0) + if (inflate_unzip(&res, zip_header->formatted.cmpsize, zip_fd, dst_fd) < 0) bb_error_msg_and_die("inflate error"); /* Validate decompression - crc */ if (zip_header->formatted.crc32 != (res.crc ^ 0xffffffffL)) { @@ -131,9 +255,12 @@ int unzip_main(int argc, char **argv) smallint verbose = 1; smallint listing = 0; smallint overwrite = O_PROMPT; +#if ENABLE_DESKTOP + uint32_t cds_offset; + unsigned cds_entries; +#endif unsigned total_size; unsigned total_entries; - int src_fd = -1; int dst_fd = -1; char *src_fn = NULL; char *dst_fn = NULL; @@ -221,13 +348,14 @@ int unzip_main(int argc, char **argv) /* Open input file */ if (LONE_DASH(src_fn)) { - src_fd = STDIN_FILENO; + xdup2(STDIN_FILENO, zip_fd); /* Cannot use prompt mode since zip data is arriving on STDIN */ if (overwrite == O_PROMPT) overwrite = O_NEVER; } else { static const char extn[][5] = {"", ".zip", ".ZIP"}; int orig_src_fn_len = strlen(src_fn); + int src_fd = -1; for (i = 0; (i < 3) && (src_fd == -1); i++) { strcpy(src_fn + orig_src_fn_len, extn[i]); @@ -237,6 +365,7 @@ int unzip_main(int argc, char **argv) src_fn[orig_src_fn_len] = '\0'; bb_error_msg_and_die("can't open %s, %s.zip, %s.ZIP", src_fn, src_fn, src_fn); } + xmove_fd(src_fd, zip_fd); } /* Change dir if necessary */ @@ -253,37 +382,63 @@ int unzip_main(int argc, char **argv) total_size = 0; total_entries = 0; +#if ENABLE_DESKTOP + cds_entries = 0; + cds_offset = 0; +#endif while (1) { uint32_t magic; /* Check magic number */ - xread(src_fd, &magic, 4); + xread(zip_fd, &magic, 4); /* Central directory? It's at the end, so exit */ if (magic == ZIP_CDS_MAGIC) break; +#if ENABLE_DESKTOP + /* Data descriptor? It was a streaming file, go on */ + if (magic == ZIP_DD_MAGIC) { + /* skip over duplicate crc32, cmpsize and ucmpsize */ + unzip_skip(3 * 4); + continue; + } +#endif if (magic != ZIP_FILEHEADER_MAGIC) bb_error_msg_and_die("invalid zip magic %08X", (int)magic); /* Read the file header */ - xread(src_fd, zip_header.raw, ZIP_HEADER_LEN); - FIX_ENDIANNESS(zip_header); + xread(zip_fd, zip_header.raw, ZIP_HEADER_LEN); + FIX_ENDIANNESS_ZIP(zip_header); if ((zip_header.formatted.method != 0) && (zip_header.formatted.method != 8)) { bb_error_msg_and_die("unsupported method %d", zip_header.formatted.method); } - if (zip_header.formatted.flags & (0x0008|0x0001)) { +#if !ENABLE_DESKTOP + if (zip_header.formatted.flags & 0x0009) { + bb_error_msg_and_die("zip flags 1 and 8 are not supported"); + } +#else + if (zip_header.formatted.flags & 0x0001) { /* 0x0001 - encrypted */ + bb_error_msg_and_die("zip flag 1 (encryption) is not supported"); + } + if (zip_header.formatted.flags & 0x0008) { + cds_header_t cds_header; /* 0x0008 - streaming. [u]cmpsize can be reliably gotten * only from Central Directory. See unzip_doc.txt */ - bb_error_msg_and_die("zip flags 8 and 1 are not supported"); + cds_offset = read_next_cds(total_entries - cds_entries, cds_offset, &cds_header); + cds_entries = total_entries + 1; + zip_header.formatted.crc32 = cds_header.formatted.crc32; + zip_header.formatted.cmpsize = cds_header.formatted.cmpsize; + zip_header.formatted.ucmpsize = cds_header.formatted.ucmpsize; } +#endif /* Read filename */ free(dst_fn); dst_fn = xzalloc(zip_header.formatted.filename_len + 1); - xread(src_fd, dst_fn, zip_header.formatted.filename_len); + xread(zip_fd, dst_fn, zip_header.formatted.filename_len); /* Skip extra header bytes */ - unzip_skip(src_fd, zip_header.formatted.extra_len); + unzip_skip(zip_header.formatted.extra_len); /* Filter zip entries */ if (find_list_entry(zreject, dst_fn) @@ -304,7 +459,6 @@ int unzip_main(int argc, char **argv) (dostime & 0x000007e0) >> 5, dst_fn); total_size += zip_header.formatted.ucmpsize; - total_entries++; } else { /* short listing -- filenames only */ puts(dst_fn); @@ -315,7 +469,7 @@ int unzip_main(int argc, char **argv) } else if (last_char_is(dst_fn, '/')) { /* Extract directory */ if (stat(dst_fn, &stat_buf) == -1) { if (errno != ENOENT) { - bb_perror_msg_and_die("cannot stat '%s'", dst_fn); + bb_perror_msg_and_die("can't stat '%s'", dst_fn); } if (verbose) { printf(" creating: %s\n", dst_fn); @@ -335,7 +489,7 @@ int unzip_main(int argc, char **argv) check_file: if (stat(dst_fn, &stat_buf) == -1) { /* File does not exist */ if (errno != ENOENT) { - bb_perror_msg_and_die("cannot stat '%s'", dst_fn); + bb_perror_msg_and_die("can't stat '%s'", dst_fn); } i = 'y'; } else { /* File already exists */ @@ -347,7 +501,7 @@ int unzip_main(int argc, char **argv) } else { printf("replace %s? [y]es, [n]o, [A]ll, [N]one, [r]ename: ", dst_fn); if (!fgets(key_buf, sizeof(key_buf), stdin)) { - bb_perror_msg_and_die("cannot read input"); + bb_perror_msg_and_die("can't read input"); } i = key_buf[0]; } @@ -368,7 +522,7 @@ int unzip_main(int argc, char **argv) if (verbose) { printf(" inflating: %s\n", dst_fn); } - unzip_extract(&zip_header, src_fd, dst_fd); + unzip_extract(&zip_header, dst_fd); if (dst_fd != STDOUT_FILENO) { /* closing STDOUT is potentially bad for future business */ close(dst_fd); @@ -379,14 +533,14 @@ int unzip_main(int argc, char **argv) overwrite = O_NEVER; case 'n': /* Skip entry data */ - unzip_skip(src_fd, zip_header.formatted.cmpsize); + unzip_skip(zip_header.formatted.cmpsize); break; case 'r': /* Prompt for new name */ printf("new name: "); if (!fgets(key_buf, sizeof(key_buf), stdin)) { - bb_perror_msg_and_die("cannot read input"); + bb_perror_msg_and_die("can't read input"); } free(dst_fn); dst_fn = xstrdup(key_buf); @@ -398,12 +552,7 @@ int unzip_main(int argc, char **argv) goto check_file; } -// Looks like bug (data descriptor cannot be identified this way) -// /* Data descriptor section */ -// if (zip_header.formatted.flags & 4) { -// /* skip over duplicate crc, compressed size and uncompressed size */ -// unzip_skip(src_fd, 12); -// } + total_entries++; } if (listing && verbose) { |