X-Git-Url: https://git.dogcows.com/gitweb?a=blobdiff_plain;f=src%2Fextract.c;h=2296066591624d6fb7bd8b8089632402cef3b225;hb=ecbcb7b6d74c2d69386c8d7e435486a4690c9993;hp=531654aabbd9184e93c18b8048ddb821c39f1804;hpb=b60e56fdb6fd8d82a1f92a4fa7781d9a3184dce1;p=chaz%2Ftar diff --git a/src/extract.c b/src/extract.c index 531654a..2296066 100644 --- a/src/extract.c +++ b/src/extract.c @@ -21,9 +21,7 @@ #include #include -#include #include -#include #include #include "common.h" @@ -70,6 +68,7 @@ struct delayed_set_stat mode_t invert_permissions; enum permstatus permstatus; bool after_links; + int change_dir; char file_name[1]; }; @@ -81,10 +80,12 @@ struct delayed_link /* The next delayed link in the list. */ struct delayed_link *next; - /* The device, inode number and last-modified time of the placeholder. */ + /* The device, inode number and ctime of the placeholder. Use + ctime, not mtime, to make false matches less likely if some + other process removes the placeholder. */ dev_t dev; ino_t ino; - struct timespec mtime; + struct timespec ctime; /* True if the link is symbolic. */ bool is_symlink; @@ -93,6 +94,9 @@ struct delayed_link uid_t uid; gid_t gid; + /* The directory that the sources and target are relative to. */ + int change_dir; + /* A list of sources for this link. The sources are all to be hard-linked together. */ struct string_list *sources; @@ -131,8 +135,40 @@ extr_init (void) } } +/* Use fchmod if possible, chmod otherwise. */ +static int +fdchmod (char const *file, int fd, mode_t mode) +{ +#if HAVE_FCHMOD + if (0 <= fd) + return fchmod (fd, mode); +#endif + return chmod (file, mode); +} + +/* Use fchown if possible, chown otherwise. */ +static int +fdchown (char const *file, int fd, uid_t uid, gid_t gid) +{ +#if HAVE_FCHOWN + if (0 <= fd) + return fchown (fd, uid, gid); +#endif + return chown (file, uid, gid); +} + +/* Use fstat if possible, stat otherwise. */ +static int +fdstat (char const *file, int fd, struct stat *st) +{ + if (0 <= fd) + return fstat (fd, st); + return stat (file, st); +} + /* If restoring permissions, restore the mode for FILE_NAME from - information given in *STAT_INFO (where *CUR_INFO gives + information given in *STAT_INFO (where FD is a file descriptor + for the file if FD is nonnegative, and where *CUR_INFO gives the current status if CUR_INFO is nonzero); otherwise invert the INVERT_PERMISSIONS bits from the file's current permissions. PERMSTATUS specifies the status of the file's permissions. @@ -140,13 +176,13 @@ extr_init (void) static void set_mode (char const *file_name, struct stat const *stat_info, - struct stat const *cur_info, + int fd, struct stat const *cur_info, mode_t invert_permissions, enum permstatus permstatus, char typeflag) { mode_t mode; - bool failed; - + int chmod_errno; + if (0 < same_permissions_option && permstatus != INTERDIR_PERMSTATUS) { @@ -178,7 +214,7 @@ set_mode (char const *file_name, struct stat st; if (! cur_info) { - if (stat (file_name, &st) != 0) + if (fdstat (file_name, fd, &st) != 0) { stat_error (file_name); return; @@ -188,18 +224,24 @@ set_mode (char const *file_name, mode = cur_info->st_mode ^ invert_permissions; } - failed = chmod (file_name, mode) != 0; - if (failed && errno == EPERM) + chmod_errno = fdchmod (file_name, fd, mode) == 0 ? 0 : errno; + if (chmod_errno == EPERM && (mode & S_ISUID) != 0) { - /* On Solaris, chmod may fail if we don't have PRIV_ALL. */ + /* On Solaris, chmod may fail if we don't have PRIV_ALL, because + setuid-root files would otherwise be a backdoor. See + http://opensolaris.org/jive/thread.jspa?threadID=95826 + (2009-09-03). */ if (priv_set_restore_linkdir () == 0) { - failed = chmod (file_name, mode) != 0; + chmod_errno = fdchmod (file_name, fd, mode) == 0 ? 0 : errno; priv_set_remove_linkdir (); } } - if (failed) - chmod_error_details (file_name, mode); + if (chmod_errno) + { + errno = chmod_errno; + chmod_error_details (file_name, mode); + } } /* Check time after successfully setting FILE_NAME's time stamp to T. */ @@ -234,6 +276,7 @@ check_time (char const *file_name, struct timespec t) /* Restore stat attributes (owner, group, mode and times) for FILE_NAME, using information given in *ST. + If FD is nonnegative, it is a file descriptor for the file. If CUR_INFO is nonzero, *CUR_INFO is the file's current status. If not restoring permissions, invert the @@ -249,7 +292,7 @@ check_time (char const *file_name, struct timespec t) static void set_stat (char const *file_name, struct tar_stat_info const *st, - struct stat const *cur_info, + int fd, struct stat const *cur_info, mode_t invert_permissions, enum permstatus permstatus, char typeflag) { @@ -260,24 +303,19 @@ set_stat (char const *file_name, if (! touch_option && permstatus != INTERDIR_PERMSTATUS) { - /* We set the accessed time to `now', which is really the time we - started extracting files, unless incremental_option is used, in - which case .st_atime is used. */ - - /* FIXME: incremental_option should set ctime too, but how? */ - struct timespec ts[2]; if (incremental_option) ts[0] = st->atime; else - ts[0] = start_time; + ts[0].tv_nsec = UTIME_NOW; ts[1] = st->mtime; - if (utimens (file_name, ts) != 0) + if (fd_utimensat (fd, AT_FDCWD, file_name, ts, 0) != 0) utime_error (file_name); else { - check_time (file_name, ts[0]); + if (incremental_option) + check_time (file_name, ts[0]); check_time (file_name, ts[1]); } } @@ -306,7 +344,8 @@ set_stat (char const *file_name, } else { - chown_result = chown (file_name, st->stat.st_uid, st->stat.st_gid); + chown_result = fdchown (file_name, fd, + st->stat.st_uid, st->stat.st_gid); } if (chown_result == 0) @@ -324,7 +363,7 @@ set_stat (char const *file_name, } if (typeflag != SYMTYPE) - set_mode (file_name, &st->stat, cur_info, + set_mode (file_name, &st->stat, fd, cur_info, invert_permissions, permstatus, typeflag); } @@ -366,6 +405,7 @@ delay_set_stat (char const *file_name, struct tar_stat_info const *st, data->invert_permissions = invert_permissions; data->permstatus = permstatus; data->after_links = 0; + data->change_dir = chdir_current; strcpy (data->file_name, file_name); delayed_set_stat_head = data; } @@ -516,7 +556,7 @@ file_newer_p (const char *file_name, struct tar_stat_info *tar_stat) properly restored on returning RECOVER_NO. */ static int -maybe_recoverable (char *file_name, int *interdir_made) +maybe_recoverable (char *file_name, bool *interdir_made) { int e = errno; @@ -561,7 +601,7 @@ maybe_recoverable (char *file_name, int *interdir_made) errno = ENOENT; return RECOVER_NO; } - *interdir_made = 1; + *interdir_made = true; return RECOVER_OK; default: @@ -599,6 +639,8 @@ apply_nonancestor_delayed_set_stat (char const *file_name, bool after_links) && memcmp (file_name, data->file_name, data->file_name_len) == 0)) break; + chdir_do (data->change_dir); + if (check_for_renamed_directories) { cur_info = &st; @@ -624,7 +666,7 @@ apply_nonancestor_delayed_set_stat (char const *file_name, bool after_links) sb.stat.st_gid = data->gid; sb.atime = data->atime; sb.mtime = data->mtime; - set_stat (data->file_name, &sb, cur_info, + set_stat (data->file_name, &sb, -1, cur_info, data->invert_permissions, data->permstatus, DIRTYPE); } @@ -642,19 +684,17 @@ extract_dir (char *file_name, int typeflag) { int status; mode_t mode; - int interdir_made = 0; + bool interdir_made = false; /* Save 'root device' to avoid purging mount points. */ if (one_file_system_option && root_device == 0) { struct stat st; - char *dir = xgetcwd (); - if (deref_stat (true, dir, &st)) - stat_diag (dir); + if (stat (".", &st) != 0) + stat_diag ("."); else root_device = st.st_dev; - free (dir); } if (incremental_option) @@ -775,7 +815,7 @@ extract_file (char *file_name, int typeflag) int status; size_t count; size_t written; - int interdir_made = 0; + bool interdir_made = false; mode_t mode = current_stat_info.stat.st_mode & MODE_RWX & ~ current_umask; mode_t invert_permissions = 0 < same_owner_option ? mode & (S_IRWXG | S_IRWXO) : 0; @@ -812,7 +852,7 @@ extract_file (char *file_name, int typeflag) } } - mv_begin (¤t_stat_info); + mv_begin_read (¤t_stat_info); if (current_stat_info.is_sparse) sparse_extract_file (fd, ¤t_stat_info, &size); else @@ -860,17 +900,18 @@ extract_file (char *file_name, int typeflag) if (to_stdout_option) return 0; + if (! to_command_option) + set_stat (file_name, ¤t_stat_info, fd, NULL, invert_permissions, + (old_files_option == OVERWRITE_OLD_FILES + ? UNKNOWN_PERMSTATUS : ARCHIVED_PERMSTATUS), + typeflag); + status = close (fd); if (status < 0) close_error (file_name); if (to_command_option) sys_wait_command (); - else - set_stat (file_name, ¤t_stat_info, NULL, invert_permissions, - (old_files_option == OVERWRITE_OLD_FILES ? - UNKNOWN_PERMSTATUS : ARCHIVED_PERMSTATUS), - typeflag); return status; } @@ -882,7 +923,7 @@ extract_file (char *file_name, int typeflag) process. */ static int -create_placeholder_file (char *file_name, bool is_symlink, int *interdir_made) +create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made) { int fd; struct stat st; @@ -893,10 +934,10 @@ create_placeholder_file (char *file_name, bool is_symlink, int *interdir_made) { case RECOVER_OK: continue; - + case RECOVER_SKIP: return 0; - + case RECOVER_NO: open_error (file_name); return -1; @@ -921,13 +962,14 @@ create_placeholder_file (char *file_name, bool is_symlink, int *interdir_made) delayed_link_head = p; p->dev = st.st_dev; p->ino = st.st_ino; - p->mtime = get_stat_mtime (&st); + p->ctime = get_stat_ctime (&st); p->is_symlink = is_symlink; if (is_symlink) { p->uid = current_stat_info.stat.st_uid; p->gid = current_stat_info.stat.st_gid; } + p->change_dir = chdir_current; p->sources = xmalloc (offsetof (struct string_list, string) + strlen (file_name) + 1); p->sources->next = 0; @@ -964,12 +1006,12 @@ create_placeholder_file (char *file_name, bool is_symlink, int *interdir_made) static int extract_link (char *file_name, int typeflag) { - int interdir_made = 0; + bool interdir_made = false; char const *link_name; int rc; - + link_name = current_stat_info.link_name; - + if (! absolute_names_option && contains_dot_dot (link_name)) return create_placeholder_file (file_name, false, &interdir_made); @@ -985,9 +1027,10 @@ extract_link (char *file_name, int typeflag) struct delayed_link *ds = delayed_link_head; if (ds && lstat (link_name, &st1) == 0) for (; ds; ds = ds->next) - if (ds->dev == st1.st_dev + if (ds->change_dir == chdir_current + && ds->dev == st1.st_dev && ds->ino == st1.st_ino - && timespec_cmp (ds->mtime, get_stat_mtime (&st1)) == 0) + && timespec_cmp (ds->ctime, get_stat_ctime (&st1)) == 0) { struct string_list *p = xmalloc (offsetof (struct string_list, string) + strlen (file_name) + 1); @@ -1023,7 +1066,7 @@ static int extract_symlink (char *file_name, int typeflag) { #ifdef HAVE_SYMLINK - int interdir_made = 0; + bool interdir_made = false; if (! absolute_names_option && (IS_ABSOLUTE_FILE_NAME (current_stat_info.link_name) @@ -1035,16 +1078,16 @@ extract_symlink (char *file_name, int typeflag) { case RECOVER_OK: continue; - + case RECOVER_SKIP: return 0; - + case RECOVER_NO: symlink_error (current_stat_info.link_name, file_name); return -1; } - - set_stat (file_name, ¤t_stat_info, NULL, 0, 0, SYMTYPE); + + set_stat (file_name, ¤t_stat_info, -1, NULL, 0, 0, SYMTYPE); return 0; #else @@ -1065,8 +1108,7 @@ extract_symlink (char *file_name, int typeflag) static int extract_node (char *file_name, int typeflag) { - int status; - int interdir_made = 0; + bool interdir_made = false; mode_t mode = current_stat_info.stat.st_mode & ~ current_umask; mode_t invert_permissions = 0 < same_owner_option ? mode & (S_IRWXG | S_IRWXO) : 0; @@ -1077,18 +1119,18 @@ extract_node (char *file_name, int typeflag) { case RECOVER_OK: continue; - + case RECOVER_SKIP: return 0; - + case RECOVER_NO: mknod_error (file_name); return -1; } - set_stat (file_name, ¤t_stat_info, NULL, invert_permissions, + set_stat (file_name, ¤t_stat_info, -1, NULL, invert_permissions, ARCHIVED_PERMSTATUS, typeflag); - return status; + return 0; } #endif @@ -1097,7 +1139,7 @@ static int extract_fifo (char *file_name, int typeflag) { int status; - int interdir_made = 0; + bool interdir_made = false; mode_t mode = current_stat_info.stat.st_mode & ~ current_umask; mode_t invert_permissions = 0 < same_owner_option ? mode & (S_IRWXG | S_IRWXO) : 0; @@ -1107,16 +1149,16 @@ extract_fifo (char *file_name, int typeflag) { case RECOVER_OK: continue; - + case RECOVER_SKIP: return 0; - + case RECOVER_NO: mkfifo_error (file_name); return -1; } - set_stat (file_name, ¤t_stat_info, NULL, invert_permissions, + set_stat (file_name, ¤t_stat_info, -1, NULL, invert_permissions, ARCHIVED_PERMSTATUS, typeflag); return 0; } @@ -1274,12 +1316,9 @@ extract_archive (void) tar_extractor_t fun; fatal_exit_hook = extract_finish; - - /* Try to disable the ability to unlink a directory. */ - priv_set_remove_linkdir (); set_next_block_after (current_header); - decode_header (current_header, ¤t_stat_info, ¤t_format, 1); + if (!current_stat_info.file_name[0] || (interactive_option && !confirm ("extract", current_stat_info.file_name))) @@ -1296,7 +1335,11 @@ extract_archive (void) it is an incremental archive. (see NOTICE in the comment to delay_set_stat above) */ if (!delay_directory_restore_option) - apply_nonancestor_delayed_set_stat (current_stat_info.file_name, 0); + { + int dir = chdir_current; + apply_nonancestor_delayed_set_stat (current_stat_info.file_name, 0); + chdir_do (dir); + } /* Take a safety backup of a previously existing file. */ @@ -1326,7 +1369,7 @@ extract_archive (void) } -/* Extract the symbolic links whose final extraction were delayed. */ +/* Extract the links whose final extraction were delayed. */ static void apply_delayed_links (void) { @@ -1337,6 +1380,8 @@ apply_delayed_links (void) struct string_list *sources = ds->sources; char const *valid_source = 0; + chdir_do (ds->change_dir); + for (sources = ds->sources; sources; sources = sources->next) { char const *source = sources->string; @@ -1348,7 +1393,7 @@ apply_delayed_links (void) if (lstat (source, &st) == 0 && st.st_dev == ds->dev && st.st_ino == ds->ino - && timespec_cmp (get_stat_mtime (&st), ds->mtime) == 0) + && timespec_cmp (get_stat_ctime (&st), ds->ctime) == 0) { /* Unlink the placeholder, then create a hard link if possible, a symbolic link otherwise. */ @@ -1368,7 +1413,7 @@ apply_delayed_links (void) struct tar_stat_info st1; st1.stat.st_uid = ds->uid; st1.stat.st_gid = ds->gid; - set_stat (source, &st1, NULL, 0, 0, SYMTYPE); + set_stat (source, &st1, -1, NULL, 0, 0, SYMTYPE); valid_source = source; } }