/* vi: set sw=4 ts=4: */ /* * Mini tar implementation for busybox * * Modifed to use common extraction code used by ar, cpio, dpkg-deb, dpkg * Glenn McGrath * * Note, that as of BusyBox-0.43, tar has been completely rewritten from the * ground up. It still has remnents of the old code lying about, but it is * very different now (i.e., cleaner, less global variables, etc.) * * Copyright (C) 1999,2000 by Lineo, inc. and Erik Andersen * Copyright (C) 1999-2002 by Erik Andersen * * Based in part in the tar implementation in sash * Copyright (c) 1999 by David I. Bell * Permission is granted to use, distribute, or modify this source, * provided that this copyright notice remains intact. * Permission to distribute sash derived code under the GPL has been granted. * * Based in part on the tar implementation from busybox-0.28 * Copyright (C) 1995 Bruce Perens * This is free software under the GNU General Public License. * * 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 * 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 #include #include "unarchive.h" #include "busybox.h" #ifdef CONFIG_FEATURE_TAR_CREATE /* Tar file constants */ # define TAR_MAGIC "ustar" /* ustar and a null */ # define TAR_VERSION " " /* Be compatable with GNU tar format */ # ifndef MAJOR # define MAJOR(dev) (((dev)>>8)&0xff) # define MINOR(dev) ((dev)&0xff) # endif static const int TAR_BLOCK_SIZE = 512; static const int TAR_MAGIC_LEN = 6; static const int TAR_VERSION_LEN = 2; /* POSIX tar Header Block, from POSIX 1003.1-1990 */ enum { NAME_SIZE = 100 }; /* because gcc won't let me use 'static const int' */ struct TarHeader { /* byte offset */ char name[NAME_SIZE]; /* 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[NAME_SIZE]; /* 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 (pad to exactly the TAR_BLOCK_SIZE) */ }; typedef struct TarHeader TarHeader; /* ** writeTarFile(), writeFileToTarball(), and writeTarHeader() are ** the only functions that deal with the HardLinkInfo structure. ** Even these functions use the xxxHardLinkInfo() functions. */ typedef struct HardLinkInfo HardLinkInfo; struct HardLinkInfo { HardLinkInfo *next; /* Next entry in list */ dev_t dev; /* Device number */ ino_t ino; /* Inode number */ short linkCount; /* (Hard) Link Count */ char name[1]; /* Start of filename (must be last) */ }; /* Some info to be carried along when creating a new tarball */ struct TarBallInfo { char *fileName; /* File name of the tarball */ int tarFd; /* Open-for-write file descriptor for the tarball */ struct stat statBuf; /* Stat info for the tarball, letting us know the inode and device that the tarball lives, so we can avoid trying to include the tarball into itself */ int verboseFlag; /* Whether to print extra stuff or not */ const llist_t *excludeList; /* List of files to not include */ HardLinkInfo *hlInfoHead; /* Hard Link Tracking Information */ HardLinkInfo *hlInfo; /* Hard Link Info for the current file */ }; typedef struct TarBallInfo TarBallInfo; /* A nice enum with all the possible tar file content types */ enum TarFileType { REGTYPE = '0', /* regular file */ REGTYPE0 = '\0', /* regular file (ancient bug compat) */ LNKTYPE = '1', /* hard link */ SYMTYPE = '2', /* symbolic link */ CHRTYPE = '3', /* character special */ BLKTYPE = '4', /* block special */ DIRTYPE = '5', /* directory */ FIFOTYPE = '6', /* FIFO special */ CONTTYPE = '7', /* reserved */ GNULONGLINK = 'K', /* GNU long (>100 chars) link name */ GNULONGNAME = 'L', /* GNU long (>100 chars) file name */ }; typedef enum TarFileType TarFileType; /* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */ static inline void addHardLinkInfo(HardLinkInfo ** hlInfoHeadPtr, struct stat *statbuf, const char *name) { /* Note: hlInfoHeadPtr can never be NULL! */ HardLinkInfo *hlInfo; hlInfo = (HardLinkInfo *) xmalloc(sizeof(HardLinkInfo) + strlen(name)); hlInfo->next = *hlInfoHeadPtr; *hlInfoHeadPtr = hlInfo; hlInfo->dev = statbuf->st_dev; hlInfo->ino = statbuf->st_ino; hlInfo->linkCount = statbuf->st_nlink; strcpy(hlInfo->name, name); } static void freeHardLinkInfo(HardLinkInfo ** hlInfoHeadPtr) { HardLinkInfo *hlInfo = NULL; HardLinkInfo *hlInfoNext = NULL; if (hlInfoHeadPtr) { hlInfo = *hlInfoHeadPtr; while (hlInfo) { hlInfoNext = hlInfo->next; free(hlInfo); hlInfo = hlInfoNext; } *hlInfoHeadPtr = NULL; } return; } /* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */ static inline HardLinkInfo *findHardLinkInfo(HardLinkInfo * hlInfo, struct stat *statbuf) { while (hlInfo) { if ((statbuf->st_ino == hlInfo->ino) && (statbuf->st_dev == hlInfo->dev)) break; hlInfo = hlInfo->next; } return (hlInfo); } /* Put an octal string into the specified buffer. * The number is zero and space padded and possibly null padded. * Returns TRUE if successful. */ static int putOctal(char *cp, int len, long value) { int tempLength; char tempBuffer[32]; char *tempString = tempBuffer; /* Create a string of the specified length with an initial space, * leading zeroes and the octal number, and a trailing null. */ sprintf(tempString, "%0*lo", len - 1, value); /* If the string is too large, suppress the leading space. */ tempLength = strlen(tempString) + 1; if (tempLength > len) { tempLength--; tempString++; } /* If the string is still too large, suppress the trailing null. */ if (tempLength > len) tempLength--; /* If the string is still too large, fail. */ if (tempLength > len) return FALSE; /* Copy the string to the field. */ memcpy(cp, tempString, len); return TRUE; } /* Write out a tar header for the specified file/directory/whatever */ static inline int writeTarHeader(struct TarBallInfo *tbInfo, const char *header_name, const char *real_name, struct stat *statbuf) { long chksum = 0; struct TarHeader header; const unsigned char *cp = (const unsigned char *) &header; ssize_t size = sizeof(struct TarHeader); memset(&header, 0, size); strncpy(header.name, header_name, sizeof(header.name)); putOctal(header.mode, sizeof(header.mode), statbuf->st_mode); putOctal(header.uid, sizeof(header.uid), statbuf->st_uid); putOctal(header.gid, sizeof(header.gid), statbuf->st_gid); putOctal(header.size, sizeof(header.size), 0); /* Regular file size is handled later */ putOctal(header.mtime, sizeof(header.mtime), statbuf->st_mtime); strncpy(header.magic, TAR_MAGIC TAR_VERSION, TAR_MAGIC_LEN + TAR_VERSION_LEN); /* Enter the user and group names (default to root if it fails) */ if (my_getpwuid(header.uname, statbuf->st_uid) == NULL) strcpy(header.uname, "root"); if (my_getgrgid(header.gname, statbuf->st_gid) == NULL) strcpy(header.gname, "root"); if (tbInfo->hlInfo) { /* This is a hard link */ header.typeflag = LNKTYPE; strncpy(header.linkname, tbInfo->hlInfo->name, sizeof(header.linkname)); } else if (S_ISLNK(statbuf->st_mode)) { char *lpath = xreadlink(real_name); if (!lpath) /* Already printed err msg inside xreadlink() */ return (FALSE); header.typeflag = SYMTYPE; strncpy(header.linkname, lpath, sizeof(header.linkname)); free(lpath); } else if (S_ISDIR(statbuf->st_mode)) { header.typeflag = DIRTYPE; strncat(header.name, "/", sizeof(header.name)); } else if (S_ISCHR(statbuf->st_mode)) { header.typeflag = CHRTYPE; putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev)); putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev)); } else if (S_ISBLK(statbuf->st_mode)) { header.typeflag = BLKTYPE; putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev)); putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev)); } else if (S_ISFIFO(statbuf->st_mode)) { header.typeflag = FIFOTYPE; } else if (S_ISREG(statbuf->st_mode)) { header.typeflag = REGTYPE; putOctal(header.size, sizeof(header.size), statbuf->st_size); } else { error_msg("%s: Unknown file type", real_name); return (FALSE); } /* Calculate and store the checksum (i.e., the sum of all of the bytes of * the header). The checksum field must be filled with blanks for the * calculation. The checksum field is formatted differently from the * other fields: it has [6] digits, a null, then a space -- rather than * digits, followed by a null like the other fields... */ memset(header.chksum, ' ', sizeof(header.chksum)); cp = (const unsigned char *) &header; while (size-- > 0) chksum += *cp++; putOctal(header.chksum, 7, chksum); /* Now write the header out to disk */ if ((size = full_write(tbInfo->tarFd, (char *) &header, sizeof(struct TarHeader))) < 0) { error_msg(io_error, real_name); return (FALSE); } /* Pad the header up to the tar block size */ for (; size < TAR_BLOCK_SIZE; size++) { write(tbInfo->tarFd, "\0", 1); } /* Now do the verbose thing (or not) */ if (tbInfo->verboseFlag) { FILE *vbFd = stdout; if (tbInfo->verboseFlag == 2) /* If the archive goes to stdout, verbose to stderr */ vbFd = stderr; fprintf(vbFd, "%s\n", header.name); } return (TRUE); } # if defined CONFIG_FEATURE_TAR_EXCLUDE static inline int exclude_file(const llist_t *excluded_files, const char *file) { if (excluded_files == NULL) { return 0; } while (excluded_files) { if (excluded_files->data[0] == '/') { if (fnmatch(excluded_files->data, file, FNM_PATHNAME | FNM_LEADING_DIR) == 0) return 1; } else { const char *p; for (p = file; p[0] != '\0'; p++) { if ((p == file || p[-1] == '/') && p[0] != '/' && fnmatch(excluded_files->data, p, FNM_PATHNAME | FNM_LEADING_DIR) == 0) return 1; } } excluded_files = excluded_files->link; } return 0; } #endif static int writeFileToTarball(const char *fileName, struct stat *statbuf, void *userData) { struct TarBallInfo *tbInfo = (struct TarBallInfo *) userData; const char *header_name; /* ** Check to see if we are dealing with a hard link. ** If so - ** Treat the first occurance of a given dev/inode as a file while ** treating any additional occurances as hard links. This is done ** by adding the file information to the HardLinkInfo linked list. */ tbInfo->hlInfo = NULL; if (statbuf->st_nlink > 1) { tbInfo->hlInfo = findHardLinkInfo(tbInfo->hlInfoHead, statbuf); if (tbInfo->hlInfo == NULL) addHardLinkInfo(&tbInfo->hlInfoHead, statbuf, fileName); } /* It is against the rules to archive a socket */ if (S_ISSOCK(statbuf->st_mode)) { error_msg("%s: socket ignored", fileName); return (TRUE); } /* It is a bad idea to store the archive we are in the process of creating, * so check the device and inode to be sure that this particular file isn't * the new tarball */ if (tbInfo->statBuf.st_dev == statbuf->st_dev && tbInfo->statBuf.st_ino == statbuf->st_ino) { error_msg("%s: file is the archive; skipping", fileName); return (TRUE); } header_name = fileName; while (header_name[0] == '/') { static int alreadyWarned = FALSE; if (alreadyWarned == FALSE) { error_msg("Removing leading '/' from member names"); alreadyWarned = TRUE; } header_name++; } if (strlen(fileName) >= NAME_SIZE) { error_msg(name_longer_than_foo, NAME_SIZE); return (TRUE); } if (header_name[0] == '\0') return TRUE; # if defined CONFIG_FEATURE_TAR_EXCLUDE if (exclude_file(tbInfo->excludeList, header_name)) { return SKIP; } # endif /* CONFIG_FEATURE_TAR_EXCLUDE */ if (writeTarHeader(tbInfo, header_name, fileName, statbuf) == FALSE) { return (FALSE); } /* Now, if the file is a regular file, copy it out to the tarball */ if ((tbInfo->hlInfo == NULL) && (S_ISREG(statbuf->st_mode))) { int inputFileFd; char buffer[BUFSIZ]; ssize_t size = 0, readSize = 0; /* open the file we want to archive, and make sure all is well */ if ((inputFileFd = open(fileName, O_RDONLY)) < 0) { perror_msg("%s: Cannot open", fileName); return (FALSE); } /* write the file to the archive */ while ((size = full_read(inputFileFd, buffer, sizeof(buffer))) > 0) { if (full_write(tbInfo->tarFd, buffer, size) != size) { /* Output file seems to have a problem */ error_msg(io_error, fileName); return (FALSE); } readSize += size; } if (size == -1) { error_msg(io_error, fileName); return (FALSE); } /* Pad the file up to the tar block size */ for (; (readSize % TAR_BLOCK_SIZE) != 0; readSize++) { write(tbInfo->tarFd, "\0", 1); } close(inputFileFd); } return (TRUE); } static inline int writeTarFile(const char *tarName, const int verboseFlag, const llist_t *include, const llist_t *exclude, const int gzip) { #ifdef CONFIG_FEATURE_TAR_GZIP int gzipDataPipe[2] = { -1, -1 }; int gzipStatusPipe[2] = { -1, -1 }; pid_t gzipPid = 0; volatile int vfork_exec_errno = 0; #endif int errorFlag = FALSE; ssize_t size; struct TarBallInfo tbInfo; tbInfo.hlInfoHead = NULL; /* Make sure there is at least one file to tar up. */ if (include == NULL) { error_msg_and_die("Cowardly refusing to create an empty archive"); } /* Open the tar file for writing. */ if (tarName == NULL || (tarName[0] == '-' && tarName[1] == '\0')) { tbInfo.tarFd = fileno(stdout); tbInfo.verboseFlag = verboseFlag ? 2 : 0; } else { tbInfo.tarFd = open(tarName, O_WRONLY | O_CREAT | O_TRUNC, 0644); tbInfo.verboseFlag = verboseFlag ? 1 : 0; } if (tbInfo.tarFd < 0) { perror_msg("%s: Cannot open", tarName); freeHardLinkInfo(&tbInfo.hlInfoHead); return (FALSE); } /* Store the stat info for the tarball's file, so * can avoid including the tarball into itself.... */ if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0) error_msg_and_die(io_error, tarName); #ifdef CONFIG_FEATURE_TAR_GZIP if (gzip) { if (pipe(gzipDataPipe) < 0 || pipe(gzipStatusPipe) < 0) { perror_msg_and_die("Failed to create gzip pipe"); } signal(SIGPIPE, SIG_IGN); /* we only want EPIPE on errors */ # if __GNUC__ /* Avoid vfork clobbering */ (void) &include; (void) &errorFlag; # endif gzipPid = vfork(); if (gzipPid == 0) { dup2(gzipDataPipe[0], 0); close(gzipDataPipe[1]); if (tbInfo.tarFd != 1); dup2(tbInfo.tarFd, 1); close(gzipStatusPipe[0]); fcntl(gzipStatusPipe[1], F_SETFD, FD_CLOEXEC); /* close on exec shows sucess */ execl("/bin/gzip", "gzip", "-f", 0); vfork_exec_errno = errno; close(gzipStatusPipe[1]); exit(-1); } else if (gzipPid > 0) { close(gzipDataPipe[0]); close(gzipStatusPipe[1]); while (1) { char buf; int n = read(gzipStatusPipe[0], &buf, 1); if (n == 0 && vfork_exec_errno != 0) { errno = vfork_exec_errno; perror_msg_and_die("Could not exec gzip process"); } else if ((n < 0) && (errno == EAGAIN || errno == EINTR)) continue; /* try it again */ break; } close(gzipStatusPipe[0]); tbInfo.tarFd = gzipDataPipe[1]; } else { perror_msg_and_die("Failed to vfork gzip process"); } } #endif tbInfo.excludeList = exclude; /* Read the directory/files and iterate over them one at a time */ while (include) { if (!recursive_action(include->data, TRUE, FALSE, FALSE, writeFileToTarball, writeFileToTarball, (void *) &tbInfo)) { errorFlag = TRUE; } include = include->link; } /* Write two empty blocks to the end of the archive */ for (size = 0; size < (2 * TAR_BLOCK_SIZE); size++) { write(tbInfo.tarFd, "\0", 1); } /* To be pedantically correct, we would check if the tarball * is smaller than 20 tar blocks, and pad it if it was smaller, * but that isn't necessary for GNU tar interoperability, and * so is considered a waste of space */ /* Hang up the tools, close up shop, head home */ close(tbInfo.tarFd); if (errorFlag) error_msg("Error exit delayed from previous errors"); freeHardLinkInfo(&tbInfo.hlInfoHead); #ifdef CONFIG_FEATURE_TAR_GZIP if (gzip && gzipPid) { if (waitpid(gzipPid, NULL, 0) == -1) printf("Couldnt wait ?"); } #endif return !errorFlag; } #endif /* tar_create */ #ifdef CONFIG_FEATURE_TAR_EXCLUDE static llist_t *append_file_list_to_list(const char *filename, llist_t *list) { FILE *src_stream = xfopen(filename, "r"); char *line; while((line = get_line_from_file(src_stream)) != NULL) { chomp(line); list = llist_add_to(list, line); } fclose(src_stream); return (list); } #endif #define CTX_CREATE 1 #define CTX_TEST 2 #define CTX_EXTRACT 4 int tar_main(int argc, char **argv) { char (*get_header_ptr)(archive_handle_t *) = get_header_tar; archive_handle_t *tar_handle; int opt; char *base_dir = NULL; const char *tar_filename = "-"; unsigned char ctx_flag = 0; if (argc < 2) { show_usage(); } /* Prepend '-' to the first argument if required */ if (argv[1][0] != '-') { char *tmp = xmalloc(strlen(argv[1]) + 2); tmp[0] = '-'; strcpy(tmp + 1, argv[1]); argv[1] = tmp; } /* Initialise default values */ tar_handle = init_handle(); tar_handle->flags = ARCHIVE_CREATE_LEADING_DIRS; while ((opt = getopt(argc, argv, "cjtxT:X:C:f:Opvz")) != -1) { switch (opt) { /* One and only one of these is required */ #ifdef CONFIG_FEATURE_TAR_CREATE case 'c': ctx_flag |= CTX_CREATE; break; #endif case 't': ctx_flag |= CTX_TEST; if ((tar_handle->action_header == header_list) || (tar_handle->action_header == header_verbose_list)) { tar_handle->action_header = header_verbose_list; } else { tar_handle->action_header = header_list; } break; case 'x': ctx_flag |= CTX_EXTRACT; tar_handle->action_data = data_extract_all; break; /* These are optional */ /* Exclude or Include files listed in */ #ifdef CONFIG_FEATURE_TAR_EXCLUDE case 'X': tar_handle->reject = append_file_list_to_list(optarg, tar_handle->reject); break; #endif case 'T': /* by default a list is an include list */ break; case 'C': /* Change to dir */ base_dir = optarg; break; case 'f': /* archive filename */ tar_filename = optarg; break; case 'O': /* To stdout */ tar_handle->action_data = data_extract_to_stdout; break; case 'p': tar_handle->flags |= ARCHIVE_PRESERVE_DATE; break; case 'v': if ((tar_handle->action_header == header_list) || (tar_handle->action_header == header_verbose_list)) { tar_handle->action_header = header_verbose_list; } else { tar_handle->action_header = header_list; } break; #ifdef CONFIG_FEATURE_TAR_GZIP case 'z': get_header_ptr = get_header_tar_gz; break; #endif #ifdef CONFIG_FEATURE_TAR_BZIP2 case 'j': get_header_ptr = get_header_tar_bz2; break; #endif default: show_usage(); } } /* Check one and only one context option was given */ if ((ctx_flag != CTX_CREATE) && (ctx_flag != CTX_TEST) && (ctx_flag != CTX_EXTRACT)) { show_usage(); } /* Check if we are reading from stdin */ if ((argv[optind]) && (*argv[optind] == '-')) { /* Default is to read from stdin, so just skip to next arg */ optind++; } /* Setup an array of filenames to work with */ /* TODO: This is the same as in ar, seperate function ? */ while (optind < argc) { tar_handle->accept = llist_add_to(tar_handle->accept, argv[optind]); optind++; } if ((tar_handle->accept) || (tar_handle->reject)) { tar_handle->filter = filter_accept_reject_list; } #ifdef CONFIG_FEATURE_TAR_CREATE /* create an archive */ if (ctx_flag == CTX_CREATE) { int verboseFlag = FALSE; int gzipFlag = FALSE; # ifdef CONFIG_FEATURE_TAR_GZIP if (get_header_ptr == get_header_tar_gz) { gzipFlag = TRUE; } # endif /* CONFIG_FEATURE_TAR_GZIP */ if (tar_handle->action_header == header_verbose_list) { verboseFlag = TRUE; } writeTarFile(tar_filename, verboseFlag, tar_handle->accept, tar_handle->reject, gzipFlag); } else #endif /* CONFIG_FEATURE_TAR_CREATE */ { if ((tar_filename[0] == '-') && (tar_filename[1] == '\0')) { tar_handle->src_fd = fileno(stdin); tar_handle->seek = seek_by_char; } else { tar_handle->src_fd = xopen(tar_filename, O_RDONLY); } if ((base_dir) && (chdir(base_dir))) { perror_msg_and_die("Couldnt chdir"); } while (get_header_ptr(tar_handle) == EXIT_SUCCESS); /* Ckeck that every file that should have been extracted was */ while (tar_handle->accept) { if (find_list_entry(tar_handle->reject, tar_handle->accept->data) == NULL) { if (find_list_entry(tar_handle->passed, tar_handle->accept->data) == NULL) { error_msg_and_die("%s: Not found in archive\n", tar_handle->accept->data); } } tar_handle->accept = tar_handle->accept->link; } } #ifdef CONFIG_FEATURE_CLEAN_UP if (tar_handle->src_fd != fileno(stdin)) { close(tar_handle->src_fd); } #endif /* CONFIG_FEATURE_CLEAN_UP */ return(EXIT_SUCCESS); }