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author | jkh <jkh@FreeBSD.org> | 1994-08-27 13:43:04 +0000 |
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committer | jkh <jkh@FreeBSD.org> | 1994-08-27 13:43:04 +0000 |
commit | 54a3fb733766ec35c7a9f85aab18eceac14b4eab (patch) | |
tree | b24ba57813a3704006e5ad4fc3af2ff2372f1394 /usr.sbin/cron/crontab/crontab.c | |
download | FreeBSD-src-54a3fb733766ec35c7a9f85aab18eceac14b4eab.zip FreeBSD-src-54a3fb733766ec35c7a9f85aab18eceac14b4eab.tar.gz |
Paul Vixie's cron, version 3.0. Munged into bmake format. If this goes
well, expect our two seperate directories for cron and crontab to go away
shortly.
Submitted by: jkh
Diffstat (limited to 'usr.sbin/cron/crontab/crontab.c')
-rw-r--r-- | usr.sbin/cron/crontab/crontab.c | 624 |
1 files changed, 624 insertions, 0 deletions
diff --git a/usr.sbin/cron/crontab/crontab.c b/usr.sbin/cron/crontab/crontab.c new file mode 100644 index 0000000..657af71 --- /dev/null +++ b/usr.sbin/cron/crontab/crontab.c @@ -0,0 +1,624 @@ +/* Copyright 1988,1990,1993,1994 by Paul Vixie + * All rights reserved + * + * Distribute freely, except: don't remove my name from the source or + * documentation (don't take credit for my work), mark your changes (don't + * get me blamed for your possible bugs), don't alter or remove this + * notice. May be sold if buildable source is provided to buyer. No + * warrantee of any kind, express or implied, is included with this + * software; use at your own risk, responsibility for damages (if any) to + * anyone resulting from the use of this software rests entirely with the + * user. + * + * Send bug reports, bug fixes, enhancements, requests, flames, etc., and + * I'll try to keep a version up to date. I can be reached as follows: + * Paul Vixie <paul@vix.com> uunet!decwrl!vixie!paul + */ + +#if !defined(lint) && !defined(LINT) +static char rcsid[] = "$Id: crontab.c,v 2.13 1994/01/17 03:20:37 vixie Exp $"; +#endif + +/* crontab - install and manage per-user crontab files + * vix 02may87 [RCS has the rest of the log] + * vix 26jan87 [original] + */ + + +#define MAIN_PROGRAM + + +#include "cron.h" +#include <errno.h> +#include <fcntl.h> +#include <sys/file.h> +#include <sys/stat.h> +#ifdef USE_UTIMES +# include <sys/time.h> +#else +# include <time.h> +# include <utime.h> +#endif +#if defined(POSIX) +# include <locale.h> +#endif + + +#define NHEADER_LINES 3 + + +enum opt_t { opt_unknown, opt_list, opt_delete, opt_edit, opt_replace }; + +#if DEBUGGING +static char *Options[] = { "???", "list", "delete", "edit", "replace" }; +#endif + + +static PID_T Pid; +static char User[MAX_UNAME], RealUser[MAX_UNAME]; +static char Filename[MAX_FNAME]; +static FILE *NewCrontab; +static int CheckErrorCount; +static enum opt_t Option; +static struct passwd *pw; +static void list_cmd __P((void)), + delete_cmd __P((void)), + edit_cmd __P((void)), + poke_daemon __P((void)), + check_error __P((char *)), + parse_args __P((int c, char *v[])); +static int replace_cmd __P((void)); + + +static void +usage(msg) + char *msg; +{ + fprintf(stderr, "%s: usage error: %s\n", ProgramName, msg); + fprintf(stderr, "usage:\t%s [-u user] file\n", ProgramName); + fprintf(stderr, "\t%s [-u user] { -e | -l | -r }\n", ProgramName); + fprintf(stderr, "\t\t(default operation is replace, per 1003.2)\n"); + fprintf(stderr, "\t-e\t(edit user's crontab)\n"); + fprintf(stderr, "\t-l\t(list user's crontab)\n"); + fprintf(stderr, "\t-r\t(delete user's crontab)\n"); + exit(ERROR_EXIT); +} + + +int +main(argc, argv) + int argc; + char *argv[]; +{ + int exitstatus; + + Pid = getpid(); + ProgramName = argv[0]; + +#if defined(POSIX) + setlocale(LC_ALL, ""); +#endif + +#if defined(BSD) + setlinebuf(stderr); +#endif + parse_args(argc, argv); /* sets many globals, opens a file */ + set_cron_uid(); + set_cron_cwd(); + if (!allowed(User)) { + fprintf(stderr, + "You (%s) are not allowed to use this program (%s)\n", + User, ProgramName); + fprintf(stderr, "See crontab(1) for more information\n"); + log_it(RealUser, Pid, "AUTH", "crontab command not allowed"); + exit(ERROR_EXIT); + } + exitstatus = OK_EXIT; + switch (Option) { + case opt_list: list_cmd(); + break; + case opt_delete: delete_cmd(); + break; + case opt_edit: edit_cmd(); + break; + case opt_replace: if (replace_cmd() < 0) + exitstatus = ERROR_EXIT; + break; + } + exit(0); + /*NOTREACHED*/ +} + + +static void +parse_args(argc, argv) + int argc; + char *argv[]; +{ + int argch; + + if (!(pw = getpwuid(getuid()))) { + fprintf(stderr, "%s: your UID isn't in the passwd file.\n", + ProgramName); + fprintf(stderr, "bailing out.\n"); + exit(ERROR_EXIT); + } + strcpy(User, pw->pw_name); + strcpy(RealUser, User); + Filename[0] = '\0'; + Option = opt_unknown; + while (EOF != (argch = getopt(argc, argv, "u:lerx:"))) { + switch (argch) { + case 'x': + if (!set_debug_flags(optarg)) + usage("bad debug option"); + break; + case 'u': + if (getuid() != ROOT_UID) + { + fprintf(stderr, + "must be privileged to use -u\n"); + exit(ERROR_EXIT); + } + if (!(pw = getpwnam(optarg))) + { + fprintf(stderr, "%s: user `%s' unknown\n", + ProgramName, optarg); + exit(ERROR_EXIT); + } + (void) strcpy(User, optarg); + break; + case 'l': + if (Option != opt_unknown) + usage("only one operation permitted"); + Option = opt_list; + break; + case 'r': + if (Option != opt_unknown) + usage("only one operation permitted"); + Option = opt_delete; + break; + case 'e': + if (Option != opt_unknown) + usage("only one operation permitted"); + Option = opt_edit; + break; + default: + usage("unrecognized option"); + } + } + + endpwent(); + + if (Option != opt_unknown) { + if (argv[optind] != NULL) { + usage("no arguments permitted after this option"); + } + } else { + if (argv[optind] != NULL) { + Option = opt_replace; + (void) strcpy (Filename, argv[optind]); + } else { + usage("file name must be specified for replace"); + } + } + + if (Option == opt_replace) { + /* we have to open the file here because we're going to + * chdir(2) into /var/cron before we get around to + * reading the file. + */ + if (!strcmp(Filename, "-")) { + NewCrontab = stdin; + } else { + /* relinquish the setuid status of the binary during + * the open, lest nonroot users read files they should + * not be able to read. we can't use access() here + * since there's a race condition. thanks go out to + * Arnt Gulbrandsen <agulbra@pvv.unit.no> for spotting + * the race. + */ + + if (swap_uids() < OK) { + perror("swapping uids"); + exit(ERROR_EXIT); + } + if (!(NewCrontab = fopen(Filename, "r"))) { + perror(Filename); + exit(ERROR_EXIT); + } + if (swap_uids() < OK) { + perror("swapping uids back"); + exit(ERROR_EXIT); + } + } + } + + Debug(DMISC, ("user=%s, file=%s, option=%s\n", + User, Filename, Options[(int)Option])) +} + + +static void +list_cmd() { + char n[MAX_FNAME]; + FILE *f; + int ch; + + log_it(RealUser, Pid, "LIST", User); + (void) sprintf(n, CRON_TAB(User)); + if (!(f = fopen(n, "r"))) { + if (errno == ENOENT) + fprintf(stderr, "no crontab for %s\n", User); + else + perror(n); + exit(ERROR_EXIT); + } + + /* file is open. copy to stdout, close. + */ + Set_LineNum(1) + while (EOF != (ch = get_char(f))) + putchar(ch); + fclose(f); +} + + +static void +delete_cmd() { + char n[MAX_FNAME]; + + log_it(RealUser, Pid, "DELETE", User); + (void) sprintf(n, CRON_TAB(User)); + if (unlink(n)) { + if (errno == ENOENT) + fprintf(stderr, "no crontab for %s\n", User); + else + perror(n); + exit(ERROR_EXIT); + } + poke_daemon(); +} + + +static void +check_error(msg) + char *msg; +{ + CheckErrorCount++; + fprintf(stderr, "\"%s\":%d: %s\n", Filename, LineNumber-1, msg); +} + + +static void +edit_cmd() { + char n[MAX_FNAME], q[MAX_TEMPSTR], *editor; + FILE *f; + int ch, t, x; + struct stat statbuf; + time_t mtime; + WAIT_T waiter; + PID_T pid, xpid; + + log_it(RealUser, Pid, "BEGIN EDIT", User); + (void) sprintf(n, CRON_TAB(User)); + if (!(f = fopen(n, "r"))) { + if (errno != ENOENT) { + perror(n); + exit(ERROR_EXIT); + } + fprintf(stderr, "no crontab for %s - using an empty one\n", + User); + if (!(f = fopen("/dev/null", "r"))) { + perror("/dev/null"); + exit(ERROR_EXIT); + } + } + + (void) sprintf(Filename, "/tmp/crontab.%d", Pid); + if (-1 == (t = open(Filename, O_CREAT|O_EXCL|O_RDWR, 0600))) { + perror(Filename); + goto fatal; + } +#ifdef HAS_FCHOWN + if (fchown(t, getuid(), getgid()) < 0) { +#else + if (chown(Filename, getuid(), getgid()) < 0) { +#endif + perror("fchown"); + goto fatal; + } + if (!(NewCrontab = fdopen(t, "r+"))) { + perror("fdopen"); + goto fatal; + } + + Set_LineNum(1) + + /* ignore the top few comments since we probably put them there. + */ + for (x = 0; x < NHEADER_LINES; x++) { + ch = get_char(f); + if (EOF == ch) + break; + if ('#' != ch) { + putc(ch, NewCrontab); + break; + } + while (EOF != (ch = get_char(f))) + if (ch == '\n') + break; + if (EOF == ch) + break; + } + + /* copy the rest of the crontab (if any) to the temp file. + */ + if (EOF != ch) + while (EOF != (ch = get_char(f))) + putc(ch, NewCrontab); + fclose(f); + if (fflush(NewCrontab) < OK) { + perror(Filename); + exit(ERROR_EXIT); + } + again: + rewind(NewCrontab); + if (ferror(NewCrontab)) { + fprintf(stderr, "%s: error while writing new crontab to %s\n", + ProgramName, Filename); + fatal: unlink(Filename); + exit(ERROR_EXIT); + } + if (fstat(t, &statbuf) < 0) { + perror("fstat"); + goto fatal; + } + mtime = statbuf.st_mtime; + + if ((!(editor = getenv("VISUAL"))) + && (!(editor = getenv("EDITOR"))) + ) { + editor = EDITOR; + } + + /* we still have the file open. editors will generally rewrite the + * original file rather than renaming/unlinking it and starting a + * new one; even backup files are supposed to be made by copying + * rather than by renaming. if some editor does not support this, + * then don't use it. the security problems are more severe if we + * close and reopen the file around the edit. + */ + + switch (pid = fork()) { + case -1: + perror("fork"); + goto fatal; + case 0: + /* child */ + if (setuid(getuid()) < 0) { + perror("setuid(getuid())"); + exit(ERROR_EXIT); + } + if (chdir("/tmp") < 0) { + perror("chdir(/tmp)"); + exit(ERROR_EXIT); + } + if (strlen(editor) + strlen(Filename) + 2 >= MAX_TEMPSTR) { + fprintf(stderr, "%s: editor or filename too long\n", + ProgramName); + exit(ERROR_EXIT); + } + sprintf(q, "%s %s", editor, Filename); + execlp(_PATH_BSHELL, _PATH_BSHELL, "-c", q, NULL); + perror(editor); + exit(ERROR_EXIT); + /*NOTREACHED*/ + default: + /* parent */ + break; + } + + /* parent */ + xpid = wait(&waiter); + if (xpid != pid) { + fprintf(stderr, "%s: wrong PID (%d != %d) from \"%s\"\n", + ProgramName, xpid, pid, editor); + goto fatal; + } + if (WIFEXITED(waiter) && WEXITSTATUS(waiter)) { + fprintf(stderr, "%s: \"%s\" exited with status %d\n", + ProgramName, editor, WEXITSTATUS(waiter)); + goto fatal; + } + if (WIFSIGNALED(waiter)) { + fprintf(stderr, + "%s: \"%s\" killed; signal %d (%score dumped)\n", + ProgramName, editor, WTERMSIG(waiter), + WCOREDUMP(waiter) ?"" :"no "); + goto fatal; + } + if (fstat(t, &statbuf) < 0) { + perror("fstat"); + goto fatal; + } + if (mtime == statbuf.st_mtime) { + fprintf(stderr, "%s: no changes made to crontab\n", + ProgramName); + goto remove; + } + fprintf(stderr, "%s: installing new crontab\n", ProgramName); + switch (replace_cmd()) { + case 0: + break; + case -1: + for (;;) { + printf("Do you want to retry the same edit? "); + fflush(stdout); + q[0] = '\0'; + (void) fgets(q, sizeof q, stdin); + switch (islower(q[0]) ? q[0] : tolower(q[0])) { + case 'y': + goto again; + case 'n': + goto abandon; + default: + fprintf(stderr, "Enter Y or N\n"); + } + } + /*NOTREACHED*/ + case -2: + abandon: + fprintf(stderr, "%s: edits left in %s\n", + ProgramName, Filename); + goto done; + default: + fprintf(stderr, "%s: panic: bad switch() in replace_cmd()\n"); + goto fatal; + } + remove: + unlink(Filename); + done: + log_it(RealUser, Pid, "END EDIT", User); +} + + +/* returns 0 on success + * -1 on syntax error + * -2 on install error + */ +static int +replace_cmd() { + char n[MAX_FNAME], envstr[MAX_ENVSTR], tn[MAX_FNAME]; + FILE *tmp; + int ch, eof; + entry *e; + time_t now = time(NULL); + char **envp = env_init(); + + (void) sprintf(n, "tmp.%d", Pid); + (void) sprintf(tn, CRON_TAB(n)); + if (!(tmp = fopen(tn, "w+"))) { + perror(tn); + return (-2); + } + + /* write a signature at the top of the file. + * + * VERY IMPORTANT: make sure NHEADER_LINES agrees with this code. + */ + fprintf(tmp, "# DO NOT EDIT THIS FILE - edit the master and reinstall.\n"); + fprintf(tmp, "# (%s installed on %-24.24s)\n", Filename, ctime(&now)); + fprintf(tmp, "# (Cron version -- %s)\n", rcsid); + + /* copy the crontab to the tmp + */ + rewind(NewCrontab); + Set_LineNum(1) + while (EOF != (ch = get_char(NewCrontab))) + putc(ch, tmp); + ftruncate(fileno(tmp), ftell(tmp)); + fflush(tmp); rewind(tmp); + + if (ferror(tmp)) { + fprintf(stderr, "%s: error while writing new crontab to %s\n", + ProgramName, tn); + fclose(tmp); unlink(tn); + return (-2); + } + + /* check the syntax of the file being installed. + */ + + /* BUG: was reporting errors after the EOF if there were any errors + * in the file proper -- kludged it by stopping after first error. + * vix 31mar87 + */ + Set_LineNum(1 - NHEADER_LINES) + CheckErrorCount = 0; eof = FALSE; + while (!CheckErrorCount && !eof) { + switch (load_env(envstr, tmp)) { + case ERR: + eof = TRUE; + break; + case FALSE: + e = load_entry(tmp, check_error, pw, envp); + if (e) + free(e); + break; + case TRUE: + break; + } + } + + if (CheckErrorCount != 0) { + fprintf(stderr, "errors in crontab file, can't install.\n"); + fclose(tmp); unlink(tn); + return (-1); + } + +#ifdef HAS_FCHOWN + if (fchown(fileno(tmp), ROOT_UID, -1) < OK) +#else + if (chown(tn, ROOT_UID, -1) < OK) +#endif + { + perror("chown"); + fclose(tmp); unlink(tn); + return (-2); + } + +#ifdef HAS_FCHMOD + if (fchmod(fileno(tmp), 0600) < OK) +#else + if (chmod(tn, 0600) < OK) +#endif + { + perror("chown"); + fclose(tmp); unlink(tn); + return (-2); + } + + if (fclose(tmp) == EOF) { + perror("fclose"); + unlink(tn); + return (-2); + } + + (void) sprintf(n, CRON_TAB(User)); + if (rename(tn, n)) { + fprintf(stderr, "%s: error renaming %s to %s\n", + ProgramName, tn, n); + perror("rename"); + unlink(tn); + return (-2); + } + log_it(RealUser, Pid, "REPLACE", User); + + poke_daemon(); + + return (0); +} + + +static void +poke_daemon() { +#ifdef USE_UTIMES + struct timeval tvs[2]; + struct timezone tz; + + (void) gettimeofday(&tvs[0], &tz); + tvs[1] = tvs[0]; + if (utimes(SPOOL_DIR, tvs) < OK) { + fprintf(stderr, "crontab: can't update mtime on spooldir\n"); + perror(SPOOL_DIR); + return; + } +#else + if (utime(SPOOL_DIR, NULL) < OK) { + fprintf(stderr, "crontab: can't update mtime on spooldir\n"); + perror(SPOOL_DIR); + return; + } +#endif /*USE_UTIMES*/ +} |