+/* vi: set sw=4 ts=4: */
/*
* CRONTAB
*
* usually setuid root, -c option only works if getuid() == geteuid()
*
* Copyright 1994 Matthew Dillon (dillon@apollo.west.oic.com)
- * May be distributed under the GNU General Public License
- *
- * Vladimir Oleynik <dzo@simtreas.ru> (C) 2002 to be used in busybox
+ * Vladimir Oleynik <dzo@simtreas.ru> (C) 2002
*
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <string.h>
-#include <errno.h>
-#include <time.h>
-#include <dirent.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <syslog.h>
-#include <signal.h>
-#include <getopt.h>
-#include <sys/ioctl.h>
-#include <sys/wait.h>
-#include <sys/stat.h>
-#include <sys/resource.h>
+#include "libbb.h"
#ifndef CRONTABS
#define CRONTABS "/var/spool/cron/crontabs"
#define CRONUPDATE "cron.update"
#endif
#ifndef PATH_VI
-#define PATH_VI "/bin/vi" /* location of vi */
+#define PATH_VI "/bin/vi" /* location of vi */
#endif
-#include "busybox.h"
-
-static const char *CDir = CRONTABS;
+static const char *CDir = CRONTABS;
static void EditFile(const char *user, const char *file);
static int GetReplaceStream(const char *user, const char *file);
-static int ChangeUser(const char *user, short dochdir);
+static int ChangeUser(const char *user, short dochdir);
-int
-crontab_main(int ac, char **av)
+int crontab_main(int ac, char **av);
+int crontab_main(int ac, char **av)
{
- enum { NONE, EDIT, LIST, REPLACE, DELETE } option = NONE;
- const struct passwd *pas;
- const char *repFile = NULL;
- int repFd = 0;
- int i;
- char caller[256]; /* user that ran program */
- int UserId;
-
- UserId = getuid();
- if ((pas = getpwuid(UserId)) == NULL)
- bb_perror_msg_and_die("getpwuid");
-
- strncpy(caller, pas->pw_name, sizeof(caller));
-
- i = 1;
- if (ac > 1) {
- if (av[1][0] == '-' && av[1][1] == 0) {
- option = REPLACE;
- ++i;
- } else if (av[1][0] != '-') {
- option = REPLACE;
- ++i;
- repFile = av[1];
- }
- }
-
- for (; i < ac; ++i) {
- char *ptr = av[i];
-
- if (*ptr != '-')
- break;
- ptr += 2;
-
- switch(ptr[-1]) {
- case 'l':
- if (ptr[-1] == 'l')
- option = LIST;
- /* fall through */
- case 'e':
- if (ptr[-1] == 'e')
- option = EDIT;
- /* fall through */
- case 'd':
- if (ptr[-1] == 'd')
- option = DELETE;
- /* fall through */
- case 'u':
- if (i + 1 < ac && av[i+1][0] != '-') {
- ++i;
- if (getuid() == geteuid()) {
- pas = getpwnam(av[i]);
- if (pas) {
- UserId = pas->pw_uid;
- } else {
- bb_error_msg_and_die("user %s unknown", av[i]);
- }
- } else {
- bb_error_msg_and_die("only the superuser may specify a user");
+ enum { NONE, EDIT, LIST, REPLACE, DELETE } option = NONE;
+ const struct passwd *pas;
+ const char *repFile = NULL;
+ int repFd = 0;
+ int i;
+ char caller[256]; /* user that ran program */
+ char buf[1024];
+ int UserId;
+
+ UserId = getuid();
+ pas = getpwuid(UserId);
+ if (pas == NULL)
+ bb_perror_msg_and_die("getpwuid");
+
+ safe_strncpy(caller, pas->pw_name, sizeof(caller));
+
+ i = 1;
+ if (ac > 1) {
+ if (LONE_DASH(av[1])) {
+ option = REPLACE;
+ ++i;
+ } else if (av[1][0] != '-') {
+ option = REPLACE;
+ ++i;
+ repFile = av[1];
}
- }
- break;
- case 'c':
- if (getuid() == geteuid()) {
- CDir = (*ptr) ? ptr : av[++i];
- } else {
- bb_error_msg_and_die("-c option: superuser only");
- }
- break;
- default:
- i = ac;
- break;
}
- }
- if (i != ac || option == NONE)
- bb_show_usage();
-
- /*
- * Get password entry
- */
-
- if ((pas = getpwuid(UserId)) == NULL)
- bb_perror_msg_and_die("getpwuid");
-
- /*
- * If there is a replacement file, obtain a secure descriptor to it.
- */
-
- if (repFile) {
- repFd = GetReplaceStream(caller, repFile);
- if (repFd < 0)
- bb_error_msg_and_die("unable to read replacement file");
- }
-
- /*
- * Change directory to our crontab directory
- */
-
- if (chdir(CDir) < 0)
- bb_perror_msg_and_die("cannot change dir to %s", CDir);
-
- /*
- * Handle options as appropriate
- */
-
- switch(option) {
- case LIST:
- {
- FILE *fi;
- char buf[1024];
-
- if ((fi = fopen(pas->pw_name, "r"))) {
- while (fgets(buf, sizeof(buf), fi) != NULL)
- fputs(buf, stdout);
- fclose(fi);
- } else {
- bb_error_msg("no crontab for %s", pas->pw_name);
- }
- }
- break;
- case EDIT:
- {
- FILE *fi;
- int fd;
- int n;
- char tmp[128];
- char buf[1024];
-
- snprintf(tmp, sizeof(tmp), TMPDIR "/crontab.%d", getpid());
- if ((fd = open(tmp, O_RDWR|O_CREAT|O_TRUNC|O_EXCL, 0600)) >= 0) {
- chown(tmp, getuid(), getgid());
- if ((fi = fopen(pas->pw_name, "r"))) {
- while ((n = fread(buf, 1, sizeof(buf), fi)) > 0)
- write(fd, buf, n);
+
+ for (; i < ac; ++i) {
+ char *ptr = av[i];
+
+ if (*ptr != '-')
+ break;
+ ptr += 2;
+
+ switch (ptr[-1]) {
+ case 'l':
+ if (ptr[-1] == 'l')
+ option = LIST;
+ /* fall through */
+ case 'e':
+ if (ptr[-1] == 'e')
+ option = EDIT;
+ /* fall through */
+ case 'd':
+ if (ptr[-1] == 'd')
+ option = DELETE;
+ /* fall through */
+ case 'u':
+ if (i + 1 < ac && av[i+1][0] != '-') {
+ ++i;
+ if (getuid() == geteuid()) {
+ pas = getpwnam(av[i]);
+ if (pas) {
+ UserId = pas->pw_uid;
+ } else {
+ bb_error_msg_and_die("user %s unknown", av[i]);
+ }
+ } else {
+ bb_error_msg_and_die("only the superuser may specify a user");
+ }
+ }
+ break;
+ case 'c':
+ if (getuid() == geteuid()) {
+ CDir = (*ptr) ? ptr : av[++i];
+ } else {
+ bb_error_msg_and_die("-c option: superuser only");
+ }
+ break;
+ default:
+ i = ac;
+ break;
}
- EditFile(caller, tmp);
- remove(tmp);
- lseek(fd, 0L, 0);
- repFd = fd;
- } else {
- bb_error_msg_and_die("unable to create %s", tmp);
- }
+ }
+ if (i != ac || option == NONE)
+ bb_show_usage();
+
+ /*
+ * Get password entry
+ */
+
+ pas = getpwuid(UserId);
+ if (pas == NULL)
+ bb_perror_msg_and_die("getpwuid");
+
+ /*
+ * If there is a replacement file, obtain a secure descriptor to it.
+ */
+ if (repFile) {
+ repFd = GetReplaceStream(caller, repFile);
+ if (repFd < 0)
+ bb_error_msg_and_die("cannot read replacement file");
}
- option = REPLACE;
- /* fall through */
- case REPLACE:
- {
- char buf[1024];
- char path[1024];
- int fd;
- int n;
-
- snprintf(path, sizeof(path), "%s.new", pas->pw_name);
- if ((fd = open(path, O_CREAT|O_TRUNC|O_APPEND|O_WRONLY, 0600)) >= 0) {
- while ((n = read(repFd, buf, sizeof(buf))) > 0) {
- write(fd, buf, n);
+
+ /*
+ * Change directory to our crontab directory
+ */
+
+ xchdir(CDir);
+
+ /*
+ * Handle options as appropriate
+ */
+
+ switch (option) {
+ case LIST:
+ {
+ FILE *fi;
+
+ fi = fopen(pas->pw_name, "r");
+ if (fi) {
+ while (fgets(buf, sizeof(buf), fi) != NULL)
+ fputs(buf, stdout);
+ fclose(fi);
+ } else {
+ bb_error_msg("no crontab for %s", pas->pw_name);
+ }
}
- close(fd);
- rename(path, pas->pw_name);
- } else {
- bb_error_msg("unable to create %s/%s", CDir, path);
- }
- close(repFd);
- }
- break;
- case DELETE:
- remove(pas->pw_name);
- break;
- case NONE:
- default:
- break;
- }
-
- /*
- * Bump notification file. Handle window where crond picks file up
- * before we can write our entry out.
- */
-
- if (option == REPLACE || option == DELETE) {
- FILE *fo;
- struct stat st;
-
- while ((fo = fopen(CRONUPDATE, "a"))) {
- fprintf(fo, "%s\n", pas->pw_name);
- fflush(fo);
- if (fstat(fileno(fo), &st) != 0 || st.st_nlink != 0) {
- fclose(fo);
break;
- }
- fclose(fo);
- /* loop */
+ case EDIT:
+ {
+/* FIXME: messy code here! we have file copying helpers for this! */
+ FILE *fi;
+ int fd;
+ int n;
+ char tmp[128];
+
+ snprintf(tmp, sizeof(tmp), TMPDIR "/crontab.%d", getpid());
+ fd = xopen3(tmp, O_RDWR|O_CREAT|O_TRUNC|O_EXCL, 0600);
+/* race, use fchown */
+ chown(tmp, getuid(), getgid());
+ fi = fopen(pas->pw_name, "r");
+ if (fi) {
+ while ((n = fread(buf, 1, sizeof(buf), fi)) > 0)
+ full_write(fd, buf, n);
+ }
+ EditFile(caller, tmp);
+ remove(tmp);
+ lseek(fd, 0L, SEEK_SET);
+ repFd = fd;
+ }
+ option = REPLACE;
+ /* fall through */
+ case REPLACE:
+ {
+/* same here */
+ char path[1024];
+ int fd;
+ int n;
+
+ snprintf(path, sizeof(path), "%s.new", pas->pw_name);
+ fd = open(path, O_CREAT|O_TRUNC|O_APPEND|O_WRONLY, 0600);
+ if (fd >= 0) {
+ while ((n = read(repFd, buf, sizeof(buf))) > 0) {
+ full_write(fd, buf, n);
+ }
+ close(fd);
+ rename(path, pas->pw_name);
+ } else {
+ bb_error_msg("cannot create %s/%s", CDir, path);
+ }
+ close(repFd);
+ }
+ break;
+ case DELETE:
+ remove(pas->pw_name);
+ break;
+ case NONE:
+ default:
+ break;
}
- if (fo == NULL) {
- bb_error_msg("unable to append to %s/%s", CDir, CRONUPDATE);
+
+ /*
+ * Bump notification file. Handle window where crond picks file up
+ * before we can write our entry out.
+ */
+
+ if (option == REPLACE || option == DELETE) {
+ FILE *fo;
+ struct stat st;
+
+ while ((fo = fopen(CRONUPDATE, "a"))) {
+ fprintf(fo, "%s\n", pas->pw_name);
+ fflush(fo);
+ if (fstat(fileno(fo), &st) != 0 || st.st_nlink != 0) {
+ fclose(fo);
+ break;
+ }
+ fclose(fo);
+ /* loop */
+ }
+ if (fo == NULL) {
+ bb_error_msg("cannot append to %s/%s", CDir, CRONUPDATE);
+ }
}
- }
- return 0;
+ return 0;
}
-static int
-GetReplaceStream(const char *user, const char *file)
+static int GetReplaceStream(const char *user, const char *file)
{
- int filedes[2];
- int pid;
- int fd;
- int n;
- char buf[1024];
-
- if (pipe(filedes) < 0) {
- perror("pipe");
- return(-1);
- }
- if ((pid = fork()) < 0) {
- perror("fork");
- return(-1);
- }
- if (pid > 0) {
+ int filedes[2];
+ int pid;
+ int fd;
+ int n;
+ char buf[1024];
+
+ if (pipe(filedes) < 0) {
+ perror("pipe");
+ return -1;
+ }
+ pid = fork();
+ if (pid < 0) {
+ perror("fork");
+ return -1;
+ }
+ if (pid > 0) {
+ /*
+ * PARENT
+ */
+
+ close(filedes[1]);
+ if (read(filedes[0], buf, 1) != 1) {
+ close(filedes[0]);
+ filedes[0] = -1;
+ }
+ return filedes[0];
+ }
+
/*
- * PARENT
+ * CHILD
*/
- close(filedes[1]);
- if (read(filedes[0], buf, 1) != 1) {
- close(filedes[0]);
- filedes[0] = -1;
- }
- return(filedes[0]);
- }
-
- /*
- * CHILD
- */
+ close(filedes[0]);
- close(filedes[0]);
+ if (ChangeUser(user, 0) < 0)
+ exit(0);
- if (ChangeUser(user, 0) < 0)
+ xfunc_error_retval = 0;
+ fd = xopen(file, O_RDONLY);
+ buf[0] = 0;
+ write(filedes[1], buf, 1);
+ while ((n = read(fd, buf, sizeof(buf))) > 0) {
+ write(filedes[1], buf, n);
+ }
exit(0);
+}
- fd = open(file, O_RDONLY);
- if (fd < 0) {
- bb_error_msg("unable to open %s", file);
- exit(0);
- }
- buf[0] = 0;
- write(filedes[1], buf, 1);
- while ((n = read(fd, buf, sizeof(buf))) > 0) {
- write(filedes[1], buf, n);
- }
- exit(0);
+static void EditFile(const char *user, const char *file)
+{
+ int pid = fork();
+
+ if (pid == 0) {
+ /*
+ * CHILD - change user and run editor
+ */
+ const char *ptr;
+
+ if (ChangeUser(user, 1) < 0)
+ exit(0);
+ ptr = getenv("VISUAL");
+ if (ptr == NULL || strlen(ptr) > 256)
+ ptr = PATH_VI;
+
+ ptr = xasprintf("%s %s", ptr, file);
+ execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", ptr, NULL);
+ bb_perror_msg_and_die("exec");
+ }
+ if (pid < 0) {
+ /*
+ * PARENT - failure
+ */
+ bb_perror_msg_and_die("fork");
+ }
+ wait4(pid, NULL, 0, NULL);
}
-static void
-EditFile(const char *user, const char *file)
+static int ChangeUser(const char *user, short dochdir)
{
- int pid;
+ struct passwd *pas;
- if ((pid = fork()) == 0) {
/*
- * CHILD - change user and run editor
+ * Obtain password entry and change privileges
*/
- char *ptr;
- char visual[1024];
- if (ChangeUser(user, 1) < 0)
- exit(0);
- if ((ptr = getenv("VISUAL")) == NULL || strlen(ptr) > 256)
- ptr = PATH_VI;
+ pas = getpwnam(user);
+ if (pas == NULL) {
+ bb_perror_msg_and_die("failed to get uid for %s", user);
+ }
+ setenv("USER", pas->pw_name, 1);
+ setenv("HOME", pas->pw_dir, 1);
+ setenv("SHELL", DEFAULT_SHELL, 1);
- snprintf(visual, sizeof(visual), "%s %s", ptr, file);
- execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", visual, NULL);
- perror("exec");
- exit(0);
- }
- if (pid < 0) {
/*
- * PARENT - failure
+ * Change running state to the user in question
*/
- bb_perror_msg_and_die("fork");
- }
- wait4(pid, NULL, 0, NULL);
-}
+ change_identity(pas);
-static int
-ChangeUser(const char *user, short dochdir)
-{
- struct passwd *pas;
-
- /*
- * Obtain password entry and change privileges
- */
-
- if ((pas = getpwnam(user)) == 0) {
- bb_perror_msg_and_die("failed to get uid for %s", user);
- return(-1);
- }
- setenv("USER", pas->pw_name, 1);
- setenv("HOME", pas->pw_dir, 1);
- setenv("SHELL", DEFAULT_SHELL, 1);
-
- /*
- * Change running state to the user in question
- */
- change_identity(pas);
-
- if (dochdir) {
- if (chdir(pas->pw_dir) < 0) {
- bb_perror_msg_and_die("chdir failed: %s %s", user, pas->pw_dir);
- if (chdir(TMPDIR) < 0) {
- bb_perror_msg_and_die("chdir failed: %s %s", user, TMPDIR);
- return(-1);
- }
+ if (dochdir) {
+ if (chdir(pas->pw_dir) < 0) {
+ bb_perror_msg("chdir(%s) by %s failed", pas->pw_dir, user);
+ xchdir(TMPDIR);
+ }
}
- }
- return(pas->pw_uid);
+ return pas->pw_uid;
}
projects / oweals / busybox.git / blobdiff