/*- * Copyright (c) 2007 Kai Wang * Copyright (c) 2007 Tim Kientzle * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer * in this position and unchanged. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "archive_platform.h" __FBSDID("$FreeBSD: head/lib/libarchive/archive_read_support_format_ar.c 201101 2009-12-28 03:06:27Z kientzle $"); #ifdef HAVE_SYS_STAT_H #include #endif #ifdef HAVE_ERRNO_H #include #endif #ifdef HAVE_STDLIB_H #include #endif #ifdef HAVE_STRING_H #include #endif #ifdef HAVE_LIMITS_H #include #endif #include "archive.h" #include "archive_entry.h" #include "archive_private.h" #include "archive_read_private.h" struct ar { off_t entry_bytes_remaining; off_t entry_offset; off_t entry_padding; char *strtab; size_t strtab_size; }; /* * Define structure of the "ar" header. */ #define AR_name_offset 0 #define AR_name_size 16 #define AR_date_offset 16 #define AR_date_size 12 #define AR_uid_offset 28 #define AR_uid_size 6 #define AR_gid_offset 34 #define AR_gid_size 6 #define AR_mode_offset 40 #define AR_mode_size 8 #define AR_size_offset 48 #define AR_size_size 10 #define AR_fmag_offset 58 #define AR_fmag_size 2 static int archive_read_format_ar_bid(struct archive_read *a); static int archive_read_format_ar_cleanup(struct archive_read *a); static int archive_read_format_ar_read_data(struct archive_read *a, const void **buff, size_t *size, off_t *offset); static int archive_read_format_ar_skip(struct archive_read *a); static int archive_read_format_ar_read_header(struct archive_read *a, struct archive_entry *e); static uint64_t ar_atol8(const char *p, unsigned char_cnt); static uint64_t ar_atol10(const char *p, unsigned char_cnt); static int ar_parse_gnu_filename_table(struct archive_read *a); static int ar_parse_common_header(struct ar *ar, struct archive_entry *, const char *h); int archive_read_support_format_ar(struct archive *_a) { struct archive_read *a = (struct archive_read *)_a; struct ar *ar; int r; ar = (struct ar *)malloc(sizeof(*ar)); if (ar == NULL) { archive_set_error(&a->archive, ENOMEM, "Can't allocate ar data"); return (ARCHIVE_FATAL); } memset(ar, 0, sizeof(*ar)); ar->strtab = NULL; r = __archive_read_register_format(a, ar, "ar", archive_read_format_ar_bid, NULL, archive_read_format_ar_read_header, archive_read_format_ar_read_data, archive_read_format_ar_skip, archive_read_format_ar_cleanup); if (r != ARCHIVE_OK) { free(ar); return (r); } return (ARCHIVE_OK); } static int archive_read_format_ar_cleanup(struct archive_read *a) { struct ar *ar; ar = (struct ar *)(a->format->data); if (ar->strtab) free(ar->strtab); free(ar); (a->format->data) = NULL; return (ARCHIVE_OK); } static int archive_read_format_ar_bid(struct archive_read *a) { const void *h; if (a->archive.archive_format != 0 && (a->archive.archive_format & ARCHIVE_FORMAT_BASE_MASK) != ARCHIVE_FORMAT_AR) return(0); /* * Verify the 8-byte file signature. * TODO: Do we need to check more than this? */ if ((h = __archive_read_ahead(a, 8, NULL)) == NULL) return (-1); if (strncmp((const char*)h, "!\n", 8) == 0) { return (64); } return (-1); } static int archive_read_format_ar_read_header(struct archive_read *a, struct archive_entry *entry) { char filename[AR_name_size + 1]; struct ar *ar; uint64_t number; /* Used to hold parsed numbers before validation. */ ssize_t bytes_read; size_t bsd_name_length, entry_size; char *p, *st; const void *b; const char *h; int r; ar = (struct ar*)(a->format->data); if (a->archive.file_position == 0) { /* * We are now at the beginning of the archive, * so we need first consume the ar global header. */ __archive_read_consume(a, 8); /* Set a default format code for now. */ a->archive.archive_format = ARCHIVE_FORMAT_AR; } /* Read the header for the next file entry. */ if ((b = __archive_read_ahead(a, 60, &bytes_read)) == NULL) /* Broken header. */ return (ARCHIVE_EOF); __archive_read_consume(a, 60); h = (const char *)b; /* Verify the magic signature on the file header. */ if (strncmp(h + AR_fmag_offset, "`\n", 2) != 0) { archive_set_error(&a->archive, EINVAL, "Incorrect file header signature"); return (ARCHIVE_WARN); } /* Copy filename into work buffer. */ strncpy(filename, h + AR_name_offset, AR_name_size); filename[AR_name_size] = '\0'; /* * Guess the format variant based on the filename. */ if (a->archive.archive_format == ARCHIVE_FORMAT_AR) { /* We don't already know the variant, so let's guess. */ /* * Biggest clue is presence of '/': GNU starts special * filenames with '/', appends '/' as terminator to * non-special names, so anything with '/' should be * GNU except for BSD long filenames. */ if (strncmp(filename, "#1/", 3) == 0) a->archive.archive_format = ARCHIVE_FORMAT_AR_BSD; else if (strchr(filename, '/') != NULL) a->archive.archive_format = ARCHIVE_FORMAT_AR_GNU; else if (strncmp(filename, "__.SYMDEF", 9) == 0) a->archive.archive_format = ARCHIVE_FORMAT_AR_BSD; /* * XXX Do GNU/SVR4 'ar' programs ever omit trailing '/' * if name exactly fills 16-byte field? If so, we * can't assume entries without '/' are BSD. XXX */ } /* Update format name from the code. */ if (a->archive.archive_format == ARCHIVE_FORMAT_AR_GNU) a->archive.archive_format_name = "ar (GNU/SVR4)"; else if (a->archive.archive_format == ARCHIVE_FORMAT_AR_BSD) a->archive.archive_format_name = "ar (BSD)"; else a->archive.archive_format_name = "ar"; /* * Remove trailing spaces from the filename. GNU and BSD * variants both pad filename area out with spaces. * This will only be wrong if GNU/SVR4 'ar' implementations * omit trailing '/' for 16-char filenames and we have * a 16-char filename that ends in ' '. */ p = filename + AR_name_size - 1; while (p >= filename && *p == ' ') { *p = '\0'; p--; } /* * Remove trailing slash unless first character is '/'. * (BSD entries never end in '/', so this will only trim * GNU-format entries. GNU special entries start with '/' * and are not terminated in '/', so we don't trim anything * that starts with '/'.) */ if (filename[0] != '/' && *p == '/') *p = '\0'; /* * '//' is the GNU filename table. * Later entries can refer to names in this table. */ if (strcmp(filename, "//") == 0) { /* This must come before any call to _read_ahead. */ ar_parse_common_header(ar, entry, h); archive_entry_copy_pathname(entry, filename); archive_entry_set_filetype(entry, AE_IFREG); /* Get the size of the filename table. */ number = ar_atol10(h + AR_size_offset, AR_size_size); if (number > SIZE_MAX) { archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Filename table too large"); return (ARCHIVE_FATAL); } entry_size = (size_t)number; if (entry_size == 0) { archive_set_error(&a->archive, EINVAL, "Invalid string table"); return (ARCHIVE_WARN); } if (ar->strtab != NULL) { archive_set_error(&a->archive, EINVAL, "More than one string tables exist"); return (ARCHIVE_WARN); } /* Read the filename table into memory. */ st = malloc(entry_size); if (st == NULL) { archive_set_error(&a->archive, ENOMEM, "Can't allocate filename table buffer"); return (ARCHIVE_FATAL); } ar->strtab = st; ar->strtab_size = entry_size; if ((b = __archive_read_ahead(a, entry_size, NULL)) == NULL) return (ARCHIVE_FATAL); memcpy(st, b, entry_size); __archive_read_consume(a, entry_size); /* All contents are consumed. */ ar->entry_bytes_remaining = 0; archive_entry_set_size(entry, ar->entry_bytes_remaining); /* Parse the filename table. */ return (ar_parse_gnu_filename_table(a)); } /* * GNU variant handles long filenames by storing / * to indicate a name stored in the filename table. * XXX TODO: Verify that it's all digits... Don't be fooled * by "/9xyz" XXX */ if (filename[0] == '/' && filename[1] >= '0' && filename[1] <= '9') { number = ar_atol10(h + AR_name_offset + 1, AR_name_size - 1); /* * If we can't look up the real name, warn and return * the entry with the wrong name. */ if (ar->strtab == NULL || number > ar->strtab_size) { archive_set_error(&a->archive, EINVAL, "Can't find long filename for entry"); archive_entry_copy_pathname(entry, filename); /* Parse the time, owner, mode, size fields. */ ar_parse_common_header(ar, entry, h); return (ARCHIVE_WARN); } archive_entry_copy_pathname(entry, &ar->strtab[(size_t)number]); /* Parse the time, owner, mode, size fields. */ return (ar_parse_common_header(ar, entry, h)); } /* * BSD handles long filenames by storing "#1/" followed by the * length of filename as a decimal number, then prepends the * the filename to the file contents. */ if (strncmp(filename, "#1/", 3) == 0) { /* Parse the time, owner, mode, size fields. */ /* This must occur before _read_ahead is called again. */ ar_parse_common_header(ar, entry, h); /* Parse the size of the name, adjust the file size. */ number = ar_atol10(h + AR_name_offset + 3, AR_name_size - 3); bsd_name_length = (size_t)number; /* Guard against the filename + trailing NUL * overflowing a size_t and against the filename size * being larger than the entire entry. */ if (number > (uint64_t)(bsd_name_length + 1) || (off_t)bsd_name_length > ar->entry_bytes_remaining) { archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Bad input file size"); return (ARCHIVE_FATAL); } ar->entry_bytes_remaining -= bsd_name_length; /* Adjust file size reported to client. */ archive_entry_set_size(entry, ar->entry_bytes_remaining); /* Read the long name into memory. */ if ((b = __archive_read_ahead(a, bsd_name_length, NULL)) == NULL) { archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Truncated input file"); return (ARCHIVE_FATAL); } __archive_read_consume(a, bsd_name_length); /* Store it in the entry. */ p = (char *)malloc(bsd_name_length + 1); if (p == NULL) { archive_set_error(&a->archive, ENOMEM, "Can't allocate fname buffer"); return (ARCHIVE_FATAL); } strncpy(p, b, bsd_name_length); p[bsd_name_length] = '\0'; archive_entry_copy_pathname(entry, p); free(p); return (ARCHIVE_OK); } /* * "/" is the SVR4/GNU archive symbol table. */ if (strcmp(filename, "/") == 0) { archive_entry_copy_pathname(entry, "/"); /* Parse the time, owner, mode, size fields. */ r = ar_parse_common_header(ar, entry, h); /* Force the file type to a regular file. */ archive_entry_set_filetype(entry, AE_IFREG); return (r); } /* * "__.SYMDEF" is a BSD archive symbol table. */ if (strcmp(filename, "__.SYMDEF") == 0) { archive_entry_copy_pathname(entry, filename); /* Parse the time, owner, mode, size fields. */ return (ar_parse_common_header(ar, entry, h)); } /* * Otherwise, this is a standard entry. The filename * has already been trimmed as much as possible, based * on our current knowledge of the format. */ archive_entry_copy_pathname(entry, filename); return (ar_parse_common_header(ar, entry, h)); } static int ar_parse_common_header(struct ar *ar, struct archive_entry *entry, const char *h) { uint64_t n; /* Copy remaining header */ archive_entry_set_mtime(entry, (time_t)ar_atol10(h + AR_date_offset, AR_date_size), 0L); archive_entry_set_uid(entry, (uid_t)ar_atol10(h + AR_uid_offset, AR_uid_size)); archive_entry_set_gid(entry, (gid_t)ar_atol10(h + AR_gid_offset, AR_gid_size)); archive_entry_set_mode(entry, (mode_t)ar_atol8(h + AR_mode_offset, AR_mode_size)); n = ar_atol10(h + AR_size_offset, AR_size_size); ar->entry_offset = 0; ar->entry_padding = n % 2; archive_entry_set_size(entry, n); ar->entry_bytes_remaining = n; return (ARCHIVE_OK); } static int archive_read_format_ar_read_data(struct archive_read *a, const void **buff, size_t *size, off_t *offset) { ssize_t bytes_read; struct ar *ar; ar = (struct ar *)(a->format->data); if (ar->entry_bytes_remaining > 0) { *buff = __archive_read_ahead(a, 1, &bytes_read); if (bytes_read == 0) { archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Truncated ar archive"); return (ARCHIVE_FATAL); } if (bytes_read < 0) return (ARCHIVE_FATAL); if (bytes_read > ar->entry_bytes_remaining) bytes_read = (ssize_t)ar->entry_bytes_remaining; *size = bytes_read; *offset = ar->entry_offset; ar->entry_offset += bytes_read; ar->entry_bytes_remaining -= bytes_read; __archive_read_consume(a, (size_t)bytes_read); return (ARCHIVE_OK); } else { while (ar->entry_padding > 0) { *buff = __archive_read_ahead(a, 1, &bytes_read); if (bytes_read <= 0) return (ARCHIVE_FATAL); if (bytes_read > ar->entry_padding) bytes_read = (ssize_t)ar->entry_padding; __archive_read_consume(a, (size_t)bytes_read); ar->entry_padding -= bytes_read; } *buff = NULL; *size = 0; *offset = ar->entry_offset; return (ARCHIVE_EOF); } } static int archive_read_format_ar_skip(struct archive_read *a) { off_t bytes_skipped; struct ar* ar; ar = (struct ar *)(a->format->data); bytes_skipped = __archive_read_skip(a, ar->entry_bytes_remaining + ar->entry_padding); if (bytes_skipped < 0) return (ARCHIVE_FATAL); ar->entry_bytes_remaining = 0; ar->entry_padding = 0; return (ARCHIVE_OK); } static int ar_parse_gnu_filename_table(struct archive_read *a) { struct ar *ar; char *p; size_t size; ar = (struct ar*)(a->format->data); size = ar->strtab_size; for (p = ar->strtab; p < ar->strtab + size - 1; ++p) { if (*p == '/') { *p++ = '\0'; if (*p != '\n') goto bad_string_table; *p = '\0'; } } /* * GNU ar always pads the table to an even size. * The pad character is either '\n' or '`'. */ if (p != ar->strtab + size && *p != '\n' && *p != '`') goto bad_string_table; /* Enforce zero termination. */ ar->strtab[size - 1] = '\0'; return (ARCHIVE_OK); bad_string_table: archive_set_error(&a->archive, EINVAL, "Invalid string table"); free(ar->strtab); ar->strtab = NULL; return (ARCHIVE_WARN); } static uint64_t ar_atol8(const char *p, unsigned char_cnt) { uint64_t l, limit, last_digit_limit; unsigned int digit, base; base = 8; limit = UINT64_MAX / base; last_digit_limit = UINT64_MAX % base; while ((*p == ' ' || *p == '\t') && char_cnt-- > 0) p++; l = 0; digit = *p - '0'; while (*p >= '0' && digit < base && char_cnt-- > 0) { if (l>limit || (l == limit && digit > last_digit_limit)) { l = UINT64_MAX; /* Truncate on overflow. */ break; } l = (l * base) + digit; digit = *++p - '0'; } return (l); } static uint64_t ar_atol10(const char *p, unsigned char_cnt) { uint64_t l, limit, last_digit_limit; unsigned int base, digit; base = 10; limit = UINT64_MAX / base; last_digit_limit = UINT64_MAX % base; while ((*p == ' ' || *p == '\t') && char_cnt-- > 0) p++; l = 0; digit = *p - '0'; while (*p >= '0' && digit < base && char_cnt-- > 0) { if (l > limit || (l == limit && digit > last_digit_limit)) { l = UINT64_MAX; /* Truncate on overflow. */ break; } l = (l * base) + digit; digit = *++p - '0'; } return (l); }