/* * Copyright (C) 2000 by Glenn McGrath * Copyright (C) 2001 by Laurence Anderson * * Based on previous work by busybox developers and others. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Library General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include #include #include #include #include #include #include #include #include #include #include "libbb.h" #define CONFIG_FEATURE_TAR_OLDGNU_COMPATABILITY 1 #define CONFIG_FEATURE_TAR_GNU_EXTENSIONS #ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS static char *longname = NULL; static char *linkname = NULL; #endif off_t archive_offset; #define SEEK_BUF 4096 static ssize_t seek_by_read(FILE* fd, size_t len) { ssize_t cc, total = 0; char buf[SEEK_BUF]; while (len) { cc = fread(buf, sizeof(buf[0]), len > SEEK_BUF ? SEEK_BUF : len, fd); total += cc; len -= cc; if(feof(fd) || ferror(fd)) break; } return total; } static void seek_sub_file(FILE *fd, const int count) { archive_offset += count; /* Do not use fseek() on a pipe. It may fail with ESPIPE, leaving the * stream at an undefined location. */ seek_by_read(fd, count); return; } /* Extract the data postioned at src_stream to either filesystem, stdout or * buffer depending on the value of 'function' which is defined in libbb.h * * prefix doesnt have to be just a directory, it may prefix the filename as well. * * e.g. '/var/lib/dpkg/info/dpkg.' will extract all files to the base bath * '/var/lib/dpkg/info/' and all files/dirs created in that dir will have * 'dpkg.' as their prefix * * For this reason if prefix does point to a dir then it must end with a * trailing '/' or else the last dir will be assumed to be the file prefix */ static char * extract_archive(FILE *src_stream, FILE *out_stream, const file_header_t *file_entry, const int function, const char *prefix, int *err) { FILE *dst_stream = NULL; char *full_name = NULL; char *full_link_name = NULL; char *buffer = NULL; struct utimbuf t; *err = 0; /* prefix doesnt have to be a proper path it may prepend * the filename as well */ if (prefix != NULL) { /* strip leading '/' in filename to extract as prefix may not be dir */ /* Cant use concat_path_file here as prefix might not be a directory */ char *path = file_entry->name; if (strncmp("./", path, 2) == 0) { path += 2; if (strlen(path) == 0) /* Do nothing, current dir already exists. */ return NULL; } full_name = xmalloc(strlen(prefix) + strlen(path) + 1); strcpy(full_name, prefix); strcat(full_name, path); if ( file_entry->link_name ){ full_link_name = xmalloc(strlen(prefix) + strlen(file_entry->link_name) + 1); strcpy(full_link_name, prefix); strcat(full_link_name, file_entry->link_name); } } else { full_name = xstrdup(file_entry->name); if ( file_entry->link_name ) full_link_name = xstrdup(file_entry->link_name); } if (function & extract_to_stream) { if (S_ISREG(file_entry->mode)) { *err = copy_file_chunk(src_stream, out_stream, file_entry->size); archive_offset += file_entry->size; } } else if (function & extract_one_to_buffer) { if (S_ISREG(file_entry->mode)) { buffer = (char *) xmalloc(file_entry->size + 1); fread(buffer, 1, file_entry->size, src_stream); buffer[file_entry->size] = '\0'; archive_offset += file_entry->size; goto cleanup; } } else if (function & extract_all_to_fs) { struct stat oldfile; int stat_res; stat_res = lstat (full_name, &oldfile); if (stat_res == 0) { /* The file already exists */ if ((function & extract_unconditional) || (oldfile.st_mtime < file_entry->mtime)) { if (!S_ISDIR(oldfile.st_mode)) { unlink(full_name); /* Directories might not be empty etc */ } } else { if ((function & extract_quiet) != extract_quiet) { *err = -1; error_msg("%s not created: newer or same age file exists", file_entry->name); } seek_sub_file(src_stream, file_entry->size); goto cleanup; } } if (function & extract_create_leading_dirs) { /* Create leading directories with default umask */ char *buf, *parent; buf = xstrdup(full_name); parent = dirname(buf); if (make_directory (parent, -1, FILEUTILS_RECUR) != 0) { if ((function & extract_quiet) != extract_quiet) { *err = -1; error_msg("couldn't create leading directories"); } } free (buf); } switch(file_entry->mode & S_IFMT) { case S_IFREG: if (file_entry->link_name) { /* Found a cpio hard link */ if (link(full_link_name, full_name) != 0) { if ((function & extract_quiet) != extract_quiet) { *err = -1; perror_msg("Cannot link from %s to '%s'", file_entry->name, file_entry->link_name); } } } else { if ((dst_stream = wfopen(full_name, "w")) == NULL) { *err = -1; seek_sub_file(src_stream, file_entry->size); goto cleanup; } archive_offset += file_entry->size; *err = copy_file_chunk(src_stream, dst_stream, file_entry->size); fclose(dst_stream); } break; case S_IFDIR: if (stat_res != 0) { if (mkdir(full_name, file_entry->mode) < 0) { if ((function & extract_quiet) != extract_quiet) { *err = -1; perror_msg("Cannot make dir %s", full_name); } } } break; case S_IFLNK: if (symlink(file_entry->link_name, full_name) < 0) { if ((function & extract_quiet) != extract_quiet) { *err = -1; perror_msg("Cannot create symlink from %s to '%s'", file_entry->name, file_entry->link_name); } goto cleanup; } break; case S_IFSOCK: case S_IFBLK: case S_IFCHR: case S_IFIFO: if (mknod(full_name, file_entry->mode, file_entry->device) == -1) { if ((function & extract_quiet) != extract_quiet) { *err = -1; perror_msg("Cannot create node %s", file_entry->name); } goto cleanup; } break; default: *err = -1; perror_msg("Don't know how to handle %s", full_name); } /* Changing a symlink's properties normally changes the properties of the * file pointed to, so dont try and change the date or mode, lchown does * does the right thing, but isnt available in older versions of libc */ if (S_ISLNK(file_entry->mode)) { #if (__GLIBC__ > 2) && (__GLIBC_MINOR__ > 1) lchown(full_name, file_entry->uid, file_entry->gid); #endif } else { if (function & extract_preserve_date) { t.actime = file_entry->mtime; t.modtime = file_entry->mtime; utime(full_name, &t); } chown(full_name, file_entry->uid, file_entry->gid); chmod(full_name, file_entry->mode); } } else { /* If we arent extracting data we have to skip it, * if data size is 0 then then just do it anyway * (saves testing for it) */ seek_sub_file(src_stream, file_entry->size); } /* extract_list and extract_verbose_list can be used in conjunction * with one of the above four extraction functions, so do this seperately */ if (function & extract_verbose_list) { fprintf(out_stream, "%s %d/%d %8d %s ", mode_string(file_entry->mode), file_entry->uid, file_entry->gid, (int) file_entry->size, time_string(file_entry->mtime)); } if ((function & extract_list) || (function & extract_verbose_list)){ /* fputs doesnt add a trailing \n, so use fprintf */ fprintf(out_stream, "%s\n", file_entry->name); } cleanup: free(full_name); if ( full_link_name ) free(full_link_name); return buffer; } static char * unarchive(FILE *src_stream, FILE *out_stream, file_header_t *(*get_headers)(FILE *), void (*free_headers)(file_header_t *), const int extract_function, const char *prefix, const char **extract_names, int *err) { file_header_t *file_entry; int extract_flag; int i; char *buffer = NULL; *err = 0; archive_offset = 0; while ((file_entry = get_headers(src_stream)) != NULL) { extract_flag = TRUE; if (extract_names != NULL) { int found_flag = FALSE; char *p = file_entry->name; if (p[0] == '.' && p[1] == '/') p += 2; for(i = 0; extract_names[i] != 0; i++) { if (strcmp(extract_names[i], p) == 0) { found_flag = TRUE; break; } } if (extract_function & extract_exclude_list) { if (found_flag == TRUE) { extract_flag = FALSE; } } else { /* If its not found in the include list dont extract it */ if (found_flag == FALSE) { extract_flag = FALSE; } } } if (extract_flag == TRUE) { buffer = extract_archive(src_stream, out_stream, file_entry, extract_function, prefix, err); *err = 0; /* XXX: ignore extraction errors */ if (*err) { free_headers(file_entry); break; } } else { /* seek past the data entry */ seek_sub_file(src_stream, file_entry->size); } free_headers(file_entry); } return buffer; } static file_header_t * get_header_ar(FILE *src_stream) { file_header_t *typed; union { char raw[60]; struct { char name[16]; char date[12]; char uid[6]; char gid[6]; char mode[8]; char size[10]; char magic[2]; } formated; } ar; static char *ar_long_names; if (fread(ar.raw, 1, 60, src_stream) != 60) { return(NULL); } archive_offset += 60; /* align the headers based on the header magic */ if ((ar.formated.magic[0] != '`') || (ar.formated.magic[1] != '\n')) { /* some version of ar, have an extra '\n' after each data entry, * this puts the next header out by 1 */ if (ar.formated.magic[1] != '`') { error_msg("Invalid magic"); return(NULL); } /* read the next char out of what would be the data section, * if its a '\n' then it is a valid header offset by 1*/ archive_offset++; if (fgetc(src_stream) != '\n') { error_msg("Invalid magic"); return(NULL); } /* fix up the header, we started reading 1 byte too early */ /* raw_header[60] wont be '\n' as it should, but it doesnt matter */ memmove(ar.raw, &ar.raw[1], 59); } typed = (file_header_t *) xcalloc(1, sizeof(file_header_t)); typed->size = (size_t) atoi(ar.formated.size); /* long filenames have '/' as the first character */ if (ar.formated.name[0] == '/') { if (ar.formated.name[1] == '/') { /* If the second char is a '/' then this entries data section * stores long filename for multiple entries, they are stored * in static variable long_names for use in future entries */ ar_long_names = (char *) xrealloc(ar_long_names, typed->size); fread(ar_long_names, 1, typed->size, src_stream); archive_offset += typed->size; /* This ar entries data section only contained filenames for other records * they are stored in the static ar_long_names for future reference */ return (get_header_ar(src_stream)); /* Return next header */ } else if (ar.formated.name[1] == ' ') { /* This is the index of symbols in the file for compilers */ seek_sub_file(src_stream, typed->size); return (get_header_ar(src_stream)); /* Return next header */ } else { /* The number after the '/' indicates the offset in the ar data section (saved in variable long_name) that conatains the real filename */ if (!ar_long_names) { error_msg("Cannot resolve long file name"); return (NULL); } typed->name = xstrdup(ar_long_names + atoi(&ar.formated.name[1])); } } else { /* short filenames */ typed->name = xcalloc(1, 16); strncpy(typed->name, ar.formated.name, 16); } typed->name[strcspn(typed->name, " /")]='\0'; /* convert the rest of the now valid char header to its typed struct */ parse_mode(ar.formated.mode, &typed->mode); typed->mtime = atoi(ar.formated.date); typed->uid = atoi(ar.formated.uid); typed->gid = atoi(ar.formated.gid); return(typed); } static void free_header_ar(file_header_t *ar_entry) { if (ar_entry == NULL) return; free(ar_entry->name); if (ar_entry->link_name) free(ar_entry->link_name); free(ar_entry); } static char uname_cache[32] = ""; static uid_t uid_cache; static bool update_unamecache(char *uname) { struct passwd *passwd; if (!uname) return FALSE; if (!uname_cache[0] && strcmp(uname_cache, uname) == 0) return TRUE; passwd = getpwnam(uname); if (passwd) { uid_cache = passwd->pw_uid; strncpy(uname, uname_cache, 32); return TRUE; } return FALSE; } static char gname_cache[32] = ""; static gid_t gid_cache; static bool update_gnamecache(char *gname) { struct group *group; if (!gname) return FALSE; if (!gname_cache[0] && strcmp(gname_cache, gname) == 0) return TRUE; group = getgrnam(gname); if (group) { gid_cache = group->gr_gid; strncpy(gname, gname_cache, 32); return TRUE; } return FALSE; } static file_header_t * get_header_tar(FILE *tar_stream) { union { unsigned char raw[512]; struct { char name[100]; /* 0-99 */ char mode[8]; /* 100-107 */ char uid[8]; /* 108-115 */ char gid[8]; /* 116-123 */ char size[12]; /* 124-135 */ char mtime[12]; /* 136-147 */ char chksum[8]; /* 148-155 */ char typeflag; /* 156-156 */ char linkname[100]; /* 157-256 */ char magic[6]; /* 257-262 */ char version[2]; /* 263-264 */ char uname[32]; /* 265-296 */ char gname[32]; /* 297-328 */ char devmajor[8]; /* 329-336 */ char devminor[8]; /* 337-344 */ char prefix[155]; /* 345-499 */ char padding[12]; /* 500-512 */ } formated; } tar; file_header_t *tar_entry = NULL; long i; long sum = 0; if (archive_offset % 512 != 0) { seek_sub_file(tar_stream, 512 - (archive_offset % 512)); } if (fread(tar.raw, 1, 512, tar_stream) != 512) { /* Unfortunately its common for tar files to have all sorts of * trailing garbage, fail silently */ // error_msg("Couldnt read header"); return(NULL); } archive_offset += 512; /* Check header has valid magic, unfortunately some tar files * have empty (0'ed) tar entries at the end, which will * cause this to fail, so fail silently for now */ if (strncmp(tar.formated.magic, "ustar", 5) != 0) { #ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATABILITY if (strncmp(tar.formated.magic, "\0\0\0\0\0", 5) != 0) #endif return(NULL); } /* Do checksum on headers */ for (i = 0; i < 148 ; i++) { sum += tar.raw[i]; } sum += ' ' * 8; for (i = 156; i < 512 ; i++) { sum += tar.raw[i]; } if (sum != strtol(tar.formated.chksum, NULL, 8)) { if ( strtol(tar.formated.chksum,NULL,8) != 0 ) error_msg("Invalid tar header checksum"); return(NULL); } /* convert to type'ed variables */ tar_entry = xcalloc(1, sizeof(file_header_t)); // tar_entry->name = xstrdup(tar.formated.name); /* parse_mode(tar.formated.mode, &tar_entry->mode); */ tar_entry->mode = 07777 & strtol(tar.formated.mode, NULL, 8); if (update_unamecache(tar.formated.uname)) tar_entry->uid = uid_cache; else tar_entry->uid = strtol(tar.formated.uid, NULL, 8); if (update_gnamecache(tar.formated.gname)) tar_entry->gid = gid_cache; else tar_entry->gid = strtol(tar.formated.gid, NULL, 8); tar_entry->size = strtol(tar.formated.size, NULL, 8); tar_entry->mtime = strtol(tar.formated.mtime, NULL, 8); tar_entry->device = (strtol(tar.formated.devmajor, NULL, 8) << 8) + strtol(tar.formated.devminor, NULL, 8); /* Fix mode, used by the old format */ switch (tar.formated.typeflag) { /* hard links are detected as regular files with 0 size and a link name */ case '1': tar_entry->mode |= S_IFREG ; break; case 0: case '0': # ifdef CONFIG_FEATURE_TAR_OLDGNU_COMPATABILITY if (last_char_is(tar_entry->name, '/')) { tar_entry->mode |= S_IFDIR; } else # endif tar_entry->mode |= S_IFREG; break; case '2': tar_entry->mode |= S_IFLNK; break; case '3': tar_entry->mode |= S_IFCHR; break; case '4': tar_entry->mode |= S_IFBLK; break; case '5': tar_entry->mode |= S_IFDIR; break; case '6': tar_entry->mode |= S_IFIFO; break; # ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS case 'L': { longname = xmalloc(tar_entry->size + 1); if(fread(longname, tar_entry->size, 1, tar_stream) != 1) return NULL; longname[tar_entry->size] = '\0'; archive_offset += tar_entry->size; return(get_header_tar(tar_stream)); } case 'K': { linkname = xmalloc(tar_entry->size + 1); if(fread(linkname, tar_entry->size, 1, tar_stream) != 1) return NULL; linkname[tar_entry->size] = '\0'; archive_offset += tar_entry->size; return(get_header_tar(tar_stream)); } case 'D': case 'M': case 'N': case 'S': case 'V': perror_msg("Ignoring GNU extension type %c", tar.formated.typeflag); # endif default: perror_msg("Unknown typeflag: 0x%x", tar.formated.typeflag); break; } #ifdef CONFIG_FEATURE_TAR_GNU_EXTENSIONS if (longname) { tar_entry->name = longname; longname = NULL; } else #endif { tar_entry->name = xstrndup(tar.formated.name, 100); if (tar.formated.prefix[0]) { char *temp = tar_entry->name; char *prefixTemp = xstrndup(tar.formated.prefix, 155); tar_entry->name = concat_path_file(prefixTemp, temp); free(temp); free(prefixTemp); } } if (linkname) { tar_entry->link_name = linkname; linkname = NULL; } else { tar_entry->link_name = *tar.formated.linkname != '\0' ? xstrndup(tar.formated.linkname, 100) : NULL; } return(tar_entry); } static void free_header_tar(file_header_t *tar_entry) { if (tar_entry == NULL) return; free(tar_entry->name); if (tar_entry->link_name) free(tar_entry->link_name); free(tar_entry); } char * deb_extract(const char *package_filename, FILE *out_stream, const int extract_function, const char *prefix, const char *filename, int *err) { FILE *deb_stream = NULL; file_header_t *ar_header = NULL; const char **file_list = NULL; char *output_buffer = NULL; char *ared_file = NULL; char ar_magic[8]; int gz_err; *err = 0; if (filename != NULL) { file_list = xmalloc(sizeof(char *) * 2); file_list[0] = filename; file_list[1] = NULL; } if (extract_function & extract_control_tar_gz) { ared_file = "control.tar.gz"; } else if (extract_function & extract_data_tar_gz) { ared_file = "data.tar.gz"; } else { opkg_msg(ERROR, "Internal error: extract_function=%x\n", extract_function); *err = -1; goto cleanup; } /* open the debian package to be worked on */ deb_stream = wfopen(package_filename, "r"); if (deb_stream == NULL) { *err = -1; goto cleanup; } /* set the buffer size */ setvbuf(deb_stream, NULL, _IOFBF, 0x8000); /* check ar magic */ fread(ar_magic, 1, 8, deb_stream); if (strncmp(ar_magic,"!",7) == 0) { archive_offset = 8; while ((ar_header = get_header_ar(deb_stream)) != NULL) { if (strcmp(ared_file, ar_header->name) == 0) { int gunzip_pid = 0; FILE *uncompressed_stream; /* open a stream of decompressed data */ uncompressed_stream = gz_open(deb_stream, &gunzip_pid); if (uncompressed_stream == NULL) { *err = -1; goto cleanup; } archive_offset = 0; output_buffer = unarchive(uncompressed_stream, out_stream, get_header_tar, free_header_tar, extract_function, prefix, file_list, err); fclose(uncompressed_stream); gz_err = gz_close(gunzip_pid); if (gz_err) *err = -1; free_header_ar(ar_header); break; } if (fseek(deb_stream, ar_header->size, SEEK_CUR) == -1) { opkg_perror(ERROR, "Couldn't fseek into %s", package_filename); *err = -1; free_header_ar(ar_header); goto cleanup; } free_header_ar(ar_header); } goto cleanup; } else if (strncmp(ar_magic, "\037\213", 2) == 0) { /* it's a gz file, let's assume it's an opkg */ int unzipped_opkg_pid; FILE *unzipped_opkg_stream; file_header_t *tar_header; archive_offset = 0; if (fseek(deb_stream, 0, SEEK_SET) == -1) { opkg_perror(ERROR, "Couldn't fseek into %s", package_filename); *err = -1; goto cleanup; } unzipped_opkg_stream = gz_open(deb_stream, &unzipped_opkg_pid); if (unzipped_opkg_stream == NULL) { *err = -1; goto cleanup; } /* walk through outer tar file to find ared_file */ while ((tar_header = get_header_tar(unzipped_opkg_stream)) != NULL) { int name_offset = 0; if (strncmp(tar_header->name, "./", 2) == 0) name_offset = 2; if (strcmp(ared_file, tar_header->name+name_offset) == 0) { int gunzip_pid = 0; FILE *uncompressed_stream; /* open a stream of decompressed data */ uncompressed_stream = gz_open(unzipped_opkg_stream, &gunzip_pid); if (uncompressed_stream == NULL) { *err = -1; goto cleanup; } archive_offset = 0; output_buffer = unarchive(uncompressed_stream, out_stream, get_header_tar, free_header_tar, extract_function, prefix, file_list, err); free_header_tar(tar_header); fclose(uncompressed_stream); gz_err = gz_close(gunzip_pid); if (gz_err) *err = -1; break; } seek_sub_file(unzipped_opkg_stream, tar_header->size); free_header_tar(tar_header); } fclose(unzipped_opkg_stream); gz_err = gz_close(unzipped_opkg_pid); if (gz_err) *err = -1; goto cleanup; } else { *err = -1; error_msg("%s: invalid magic", package_filename); } cleanup: if (deb_stream) fclose(deb_stream); if (file_list) free(file_list); return output_buffer; }