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-rw-r--r--src/groupmems.c632
1 files changed, 632 insertions, 0 deletions
diff --git a/src/groupmems.c b/src/groupmems.c
new file mode 100644
index 0000000..a0e3266
--- /dev/null
+++ b/src/groupmems.c
@@ -0,0 +1,632 @@
+/*
+ * SPDX-FileCopyrightText: 2000 , International Business Machines
+ * SPDX-FileCopyrightText: 2000 , George Kraft IV, gk4@us.ibm.com, 03/23/2000
+ * SPDX-FileCopyrightText: 2000 - 2006, Tomasz Kłoczko
+ * SPDX-FileCopyrightText: 2007 - 2011, Nicolas François
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <config.h>
+
+#include <fcntl.h>
+#include <getopt.h>
+#include <grp.h>
+#include <stdio.h>
+#include <sys/types.h>
+#ifdef USE_PAM
+#include "pam_defs.h"
+#endif /* USE_PAM */
+#include <pwd.h>
+#include "defines.h"
+#include "prototypes.h"
+#include "groupio.h"
+#ifdef SHADOWGRP
+#include "sgroupio.h"
+#endif
+#include "shadowlog.h"
+
+/* Exit Status Values */
+/*@-exitarg@*/
+#define EXIT_SUCCESS 0 /* success */
+#define EXIT_USAGE 1 /* invalid command syntax */
+#define EXIT_GROUP_FILE 2 /* group file access problems */
+#define EXIT_NOT_ROOT 3 /* not superuser */
+#define EXIT_NOT_EROOT 4 /* not effective superuser */
+#define EXIT_NOT_PRIMARY 5 /* not primary owner of group */
+#define EXIT_NOT_MEMBER 6 /* member of group does not exist */
+#define EXIT_MEMBER_EXISTS 7 /* member of group already exists */
+#define EXIT_INVALID_USER 8 /* specified user does not exist */
+#define EXIT_INVALID_GROUP 9 /* specified group does not exist */
+
+/*
+ * Global variables
+ */
+const char *Prog;
+
+static char *adduser = NULL;
+static char *deluser = NULL;
+static char *thisgroup = NULL;
+static bool purge = false;
+static bool list = false;
+static int exclusive = 0;
+static bool gr_locked = false;
+#ifdef SHADOWGRP
+/* Indicate if shadow groups are enabled on the system
+ * (/etc/gshadow present) */
+static bool is_shadowgrp;
+static bool sgr_locked = false;
+#endif
+
+/* local function prototypes */
+static char *whoami (void);
+static void add_user (const char *user,
+ const struct group *grp);
+static void remove_user (const char *user,
+ const struct group *grp);
+static void purge_members (const struct group *grp);
+static void display_members (const char *const *members);
+static /*@noreturn@*/void usage (int status);
+static void process_flags (int argc, char **argv);
+static void check_perms (void);
+static void fail_exit (int code);
+#define isroot() (getuid () == 0)
+
+static char *whoami (void)
+{
+ /* local, no need for xgetgrgid */
+ struct group *grp = getgrgid (getgid ());
+ /* local, no need for xgetpwuid */
+ struct passwd *usr = getpwuid (getuid ());
+
+ if ( (NULL != usr)
+ && (NULL != grp)
+ && (0 == strcmp (usr->pw_name, grp->gr_name))) {
+ return xstrdup (usr->pw_name);
+ } else {
+ return NULL;
+ }
+}
+
+/*
+ * add_user - Add an user to the specified group
+ */
+static void add_user (const char *user,
+ const struct group *grp)
+{
+ struct group *newgrp;
+
+ /* Make sure the user is not already part of the group */
+ if (is_on_list (grp->gr_mem, user)) {
+ fprintf (stderr,
+ _("%s: user '%s' is already a member of '%s'\n"),
+ Prog, user, grp->gr_name);
+ fail_exit (EXIT_MEMBER_EXISTS);
+ }
+
+ newgrp = __gr_dup(grp);
+ if (NULL == newgrp) {
+ fprintf (stderr,
+ _("%s: Out of memory. Cannot update %s.\n"),
+ Prog, gr_dbname ());
+ fail_exit (13);
+ }
+
+ /* Add the user to the /etc/group group */
+ newgrp->gr_mem = add_list (newgrp->gr_mem, user);
+
+#ifdef SHADOWGRP
+ if (is_shadowgrp) {
+ const struct sgrp *sg = sgr_locate (newgrp->gr_name);
+ struct sgrp *newsg;
+
+ if (NULL == sg) {
+ /* Create a shadow group based on this group */
+ static struct sgrp sgrent;
+ sgrent.sg_name = xstrdup (newgrp->gr_name);
+ sgrent.sg_mem = dup_list (newgrp->gr_mem);
+ sgrent.sg_adm = (char **) xmalloc (sizeof (char *));
+#ifdef FIRST_MEMBER_IS_ADMIN
+ if (sgrent.sg_mem[0]) {
+ sgrent.sg_adm[0] = xstrdup (sgrent.sg_mem[0]);
+ sgrent.sg_adm[1] = NULL;
+ } else
+#endif
+ {
+ sgrent.sg_adm[0] = NULL;
+ }
+
+ /* Move any password to gshadow */
+ sgrent.sg_passwd = newgrp->gr_passwd;
+ newgrp->gr_passwd = SHADOW_PASSWD_STRING;
+
+ newsg = &sgrent;
+ } else {
+ newsg = __sgr_dup (sg);
+ if (NULL == newsg) {
+ fprintf (stderr,
+ _("%s: Out of memory. Cannot update %s.\n"),
+ Prog, sgr_dbname ());
+ fail_exit (13);
+ }
+ /* Add the user to the members */
+ newsg->sg_mem = add_list (newsg->sg_mem, user);
+ /* Do not touch the administrators */
+ }
+
+ if (sgr_update (newsg) == 0) {
+ fprintf (stderr,
+ _("%s: failed to prepare the new %s entry '%s'\n"),
+ Prog, sgr_dbname (), newsg->sg_name);
+ fail_exit (13);
+ }
+ }
+#endif
+
+ if (gr_update (newgrp) == 0) {
+ fprintf (stderr,
+ _("%s: failed to prepare the new %s entry '%s'\n"),
+ Prog, gr_dbname (), newgrp->gr_name);
+ fail_exit (13);
+ }
+}
+
+/*
+ * remove_user - Remove an user from a given group
+ */
+static void remove_user (const char *user,
+ const struct group *grp)
+{
+ struct group *newgrp;
+
+ /* Check if the user is a member of the specified group */
+ if (!is_on_list (grp->gr_mem, user)) {
+ fprintf (stderr,
+ _("%s: user '%s' is not a member of '%s'\n"),
+ Prog, user, grp->gr_name);
+ fail_exit (EXIT_NOT_MEMBER);
+ }
+
+ newgrp = __gr_dup (grp);
+ if (NULL == newgrp) {
+ fprintf (stderr,
+ _("%s: Out of memory. Cannot update %s.\n"),
+ Prog, gr_dbname ());
+ fail_exit (13);
+ }
+
+ /* Remove the user from the /etc/group group */
+ newgrp->gr_mem = del_list (newgrp->gr_mem, user);
+
+#ifdef SHADOWGRP
+ if (is_shadowgrp) {
+ const struct sgrp *sg = sgr_locate (newgrp->gr_name);
+ struct sgrp *newsg;
+
+ if (NULL == sg) {
+ /* Create a shadow group based on this group */
+ static struct sgrp sgrent;
+ sgrent.sg_name = xstrdup (newgrp->gr_name);
+ sgrent.sg_mem = dup_list (newgrp->gr_mem);
+ sgrent.sg_adm = (char **) xmalloc (sizeof (char *));
+#ifdef FIRST_MEMBER_IS_ADMIN
+ if (sgrent.sg_mem[0]) {
+ sgrent.sg_adm[0] = xstrdup (sgrent.sg_mem[0]);
+ sgrent.sg_adm[1] = NULL;
+ } else
+#endif
+ {
+ sgrent.sg_adm[0] = NULL;
+ }
+
+ /* Move any password to gshadow */
+ sgrent.sg_passwd = newgrp->gr_passwd;
+ newgrp->gr_passwd = SHADOW_PASSWD_STRING;
+
+ newsg = &sgrent;
+ } else {
+ newsg = __sgr_dup (sg);
+ if (NULL == newsg) {
+ fprintf (stderr,
+ _("%s: Out of memory. Cannot update %s.\n"),
+ Prog, sgr_dbname ());
+ fail_exit (13);
+ }
+ /* Remove the user from the members */
+ newsg->sg_mem = del_list (newsg->sg_mem, user);
+ /* Remove the user from the administrators */
+ newsg->sg_adm = del_list (newsg->sg_adm, user);
+ }
+
+ if (sgr_update (newsg) == 0) {
+ fprintf (stderr,
+ _("%s: failed to prepare the new %s entry '%s'\n"),
+ Prog, sgr_dbname (), newsg->sg_name);
+ fail_exit (13);
+ }
+ }
+#endif
+
+ if (gr_update (newgrp) == 0) {
+ fprintf (stderr,
+ _("%s: failed to prepare the new %s entry '%s'\n"),
+ Prog, gr_dbname (), newgrp->gr_name);
+ fail_exit (13);
+ }
+}
+
+/*
+ * purge_members - Remove every members of the specified group
+ */
+static void purge_members (const struct group *grp)
+{
+ struct group *newgrp = __gr_dup (grp);
+
+ if (NULL == newgrp) {
+ fprintf (stderr,
+ _("%s: Out of memory. Cannot update %s.\n"),
+ Prog, gr_dbname ());
+ fail_exit (13);
+ }
+
+ /* Remove all the members of the /etc/group group */
+ newgrp->gr_mem[0] = NULL;
+
+#ifdef SHADOWGRP
+ if (is_shadowgrp) {
+ const struct sgrp *sg = sgr_locate (newgrp->gr_name);
+ struct sgrp *newsg;
+
+ if (NULL == sg) {
+ /* Create a shadow group based on this group */
+ static struct sgrp sgrent;
+ sgrent.sg_name = xstrdup (newgrp->gr_name);
+ sgrent.sg_mem = (char **) xmalloc (sizeof (char *));
+ sgrent.sg_mem[0] = NULL;
+ sgrent.sg_adm = (char **) xmalloc (sizeof (char *));
+ sgrent.sg_adm[0] = NULL;
+
+ /* Move any password to gshadow */
+ sgrent.sg_passwd = newgrp->gr_passwd;
+ newgrp->gr_passwd = xstrdup(SHADOW_PASSWD_STRING);
+
+ newsg = &sgrent;
+ } else {
+ newsg = __sgr_dup (sg);
+ if (NULL == newsg) {
+ fprintf (stderr,
+ _("%s: Out of memory. Cannot update %s.\n"),
+ Prog, sgr_dbname ());
+ fail_exit (13);
+ }
+ /* Remove all the members of the /etc/gshadow
+ * group */
+ newsg->sg_mem[0] = NULL;
+ /* Remove all the administrators of the
+ * /etc/gshadow group */
+ newsg->sg_adm[0] = NULL;
+ }
+
+ if (sgr_update (newsg) == 0) {
+ fprintf (stderr,
+ _("%s: failed to prepare the new %s entry '%s'\n"),
+ Prog, sgr_dbname (), newsg->sg_name);
+ fail_exit (13);
+ }
+ }
+#endif
+
+ if (gr_update (newgrp) == 0) {
+ fprintf (stderr,
+ _("%s: failed to prepare the new %s entry '%s'\n"),
+ Prog, gr_dbname (), newgrp->gr_name);
+ fail_exit (13);
+ }
+}
+
+static void display_members (const char *const *members)
+{
+ int i;
+
+ for (i = 0; NULL != members[i]; i++) {
+ printf ("%s ", members[i]);
+
+ if (NULL == members[i + 1]) {
+ printf ("\n");
+ } else {
+ printf (" ");
+ }
+ }
+}
+
+static /*@noreturn@*/void usage (int status)
+{
+ FILE *usageout = (EXIT_SUCCESS != status) ? stderr : stdout;
+ (void) fprintf (usageout,
+ _("Usage: %s [options] [action]\n"
+ "\n"
+ "Options:\n"),
+ Prog);
+ (void) fputs (_(" -g, --group groupname change groupname instead of the user's group\n"
+ " (root only)\n"), usageout);
+ (void) fputs (_(" -R, --root CHROOT_DIR directory to chroot into\n"), usageout);
+ (void) fputs (_("\n"), usageout);
+ (void) fputs (_("Actions:\n"), usageout);
+ (void) fputs (_(" -a, --add username add username to the members of the group\n"), usageout);
+ (void) fputs (_(" -d, --delete username remove username from the members of the group\n"), usageout);
+ (void) fputs (_(" -h, --help display this help message and exit\n"), usageout);
+ (void) fputs (_(" -p, --purge purge all members from the group\n"), usageout);
+ (void) fputs (_(" -l, --list list the members of the group\n"), usageout);
+ exit (status);
+}
+
+/*
+ * process_flags - perform command line argument setting
+ */
+static void process_flags (int argc, char **argv)
+{
+ int c;
+ static struct option long_options[] = {
+ {"add", required_argument, NULL, 'a'},
+ {"delete", required_argument, NULL, 'd'},
+ {"group", required_argument, NULL, 'g'},
+ {"help", no_argument, NULL, 'h'},
+ {"list", no_argument, NULL, 'l'},
+ {"purge", no_argument, NULL, 'p'},
+ {"root", required_argument, NULL, 'R'},
+ {NULL, 0, NULL, '\0'}
+ };
+
+ while ((c = getopt_long (argc, argv, "a:d:g:hlpR:",
+ long_options, NULL)) != EOF) {
+ switch (c) {
+ case 'a':
+ adduser = xstrdup (optarg);
+ ++exclusive;
+ break;
+ case 'd':
+ deluser = xstrdup (optarg);
+ ++exclusive;
+ break;
+ case 'g':
+ thisgroup = xstrdup (optarg);
+ break;
+ case 'h':
+ usage (EXIT_SUCCESS);
+ /*@notreached@*/break;
+ case 'l':
+ list = true;
+ ++exclusive;
+ break;
+ case 'p':
+ purge = true;
+ ++exclusive;
+ break;
+ case 'R': /* no-op, handled in process_root_flag () */
+ break;
+ default:
+ usage (EXIT_USAGE);
+ }
+ }
+
+ if ((exclusive > 1) || (optind < argc)) {
+ usage (EXIT_USAGE);
+ }
+
+ /* local, no need for xgetpwnam */
+ if ( (NULL != adduser)
+ && (getpwnam (adduser) == NULL)) {
+ fprintf (stderr, _("%s: user '%s' does not exist\n"),
+ Prog, adduser);
+ fail_exit (EXIT_INVALID_USER);
+ }
+
+}
+
+static void check_perms (void)
+{
+ if (!list) {
+#ifdef USE_PAM
+ pam_handle_t *pamh = NULL;
+ int retval;
+ struct passwd *pampw;
+
+ pampw = getpwuid (getuid ()); /* local, no need for xgetpwuid */
+ if (NULL == pampw) {
+ fprintf (stderr,
+ _("%s: Cannot determine your user name.\n"),
+ Prog);
+ fail_exit (1);
+ }
+
+ retval = pam_start ("groupmems", pampw->pw_name, &conv, &pamh);
+
+ if (PAM_SUCCESS == retval) {
+ retval = pam_authenticate (pamh, 0);
+ }
+
+ if (PAM_SUCCESS == retval) {
+ retval = pam_acct_mgmt (pamh, 0);
+ }
+
+ if (PAM_SUCCESS != retval) {
+ fprintf (stderr, _("%s: PAM: %s\n"),
+ Prog, pam_strerror (pamh, retval));
+ SYSLOG((LOG_ERR, "%s", pam_strerror (pamh, retval)));
+ if (NULL != pamh) {
+ (void) pam_end (pamh, retval);
+ }
+ fail_exit (1);
+ }
+ (void) pam_end (pamh, retval);
+#endif
+ }
+}
+
+static void fail_exit (int code)
+{
+ if (gr_locked) {
+ if (gr_unlock () == 0) {
+ fprintf (stderr,
+ _("%s: failed to unlock %s\n"),
+ Prog, gr_dbname ());
+ SYSLOG ((LOG_ERR, "failed to unlock %s", gr_dbname ()));
+ /* continue */
+ }
+ }
+
+#ifdef SHADOWGRP
+ if (sgr_locked) {
+ if (sgr_unlock () == 0) {
+ fprintf (stderr,
+ _("%s: failed to unlock %s\n"),
+ Prog, sgr_dbname ());
+ SYSLOG ((LOG_ERR, "failed to unlock %s", sgr_dbname ()));
+ /* continue */
+ }
+ }
+#endif
+
+ exit (code);
+}
+
+static void open_files (void)
+{
+ if (!list) {
+ if (gr_lock () == 0) {
+ fprintf (stderr,
+ _("%s: cannot lock %s; try again later.\n"),
+ Prog, gr_dbname ());
+ fail_exit (EXIT_GROUP_FILE);
+ }
+ gr_locked = true;
+
+#ifdef SHADOWGRP
+ if (is_shadowgrp) {
+ if (sgr_lock () == 0) {
+ fprintf (stderr,
+ _("%s: cannot lock %s; try again later.\n"),
+ Prog, sgr_dbname ());
+ fail_exit (EXIT_GROUP_FILE);
+ }
+ sgr_locked = true;
+ }
+#endif
+ }
+
+ if (gr_open (list ? O_RDONLY : O_CREAT | O_RDWR) == 0) {
+ fprintf (stderr, _("%s: cannot open %s\n"), Prog, gr_dbname ());
+ fail_exit (EXIT_GROUP_FILE);
+ }
+
+#ifdef SHADOWGRP
+ if (is_shadowgrp) {
+ if (sgr_open (list ? O_RDONLY : O_CREAT | O_RDWR) == 0) {
+ fprintf (stderr, _("%s: cannot open %s\n"), Prog, sgr_dbname ());
+ fail_exit (EXIT_GROUP_FILE);
+ }
+ }
+#endif
+}
+
+static void close_files (void)
+{
+ if ((gr_close () == 0) && !list) {
+ fprintf (stderr, _("%s: failure while writing changes to %s\n"), Prog, gr_dbname ());
+ SYSLOG ((LOG_ERR, "failure while writing changes to %s", gr_dbname ()));
+ fail_exit (EXIT_GROUP_FILE);
+ }
+ if (gr_locked) {
+ if (gr_unlock () == 0) {
+ fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, gr_dbname ());
+ SYSLOG ((LOG_ERR, "failed to unlock %s", gr_dbname ()));
+ /* continue */
+ }
+ gr_locked = false;
+ }
+
+#ifdef SHADOWGRP
+ if (is_shadowgrp) {
+ if ((sgr_close () == 0) && !list) {
+ fprintf (stderr, _("%s: failure while writing changes to %s\n"), Prog, sgr_dbname ());
+ SYSLOG ((LOG_ERR, "failure while writing changes to %s", sgr_dbname ()));
+ fail_exit (EXIT_GROUP_FILE);
+ }
+ if (sgr_locked) {
+ if (sgr_unlock () == 0) {
+ fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, sgr_dbname ());
+ SYSLOG ((LOG_ERR, "failed to unlock %s", sgr_dbname ()));
+ /* continue */
+ }
+ sgr_locked = false;
+ }
+ }
+#endif
+}
+
+int main (int argc, char **argv)
+{
+ char *name;
+ const struct group *grp;
+
+ /*
+ * Get my name so that I can use it to report errors.
+ */
+ Prog = Basename (argv[0]);
+ log_set_progname(Prog);
+ log_set_logfd(stderr);
+
+ (void) setlocale (LC_ALL, "");
+ (void) bindtextdomain (PACKAGE, LOCALEDIR);
+ (void) textdomain (PACKAGE);
+
+ process_root_flag ("-R", argc, argv);
+
+ OPENLOG ("groupmems");
+
+#ifdef SHADOWGRP
+ is_shadowgrp = sgr_file_present ();
+#endif
+
+ process_flags (argc, argv);
+
+ if (NULL == thisgroup) {
+ name = whoami ();
+ if (!list && (NULL == name)) {
+ fprintf (stderr, _("%s: your groupname does not match your username\n"), Prog);
+ fail_exit (EXIT_NOT_PRIMARY);
+ }
+ } else {
+ name = thisgroup;
+ if (!list && !isroot ()) {
+ fprintf (stderr, _("%s: only root can use the -g/--group option\n"), Prog);
+ fail_exit (EXIT_NOT_ROOT);
+ }
+ }
+
+ check_perms ();
+
+ open_files ();
+
+ grp = gr_locate (name);
+ if (NULL == grp) {
+ fprintf (stderr, _("%s: group '%s' does not exist in %s\n"),
+ Prog, name, gr_dbname ());
+ fail_exit (EXIT_INVALID_GROUP);
+ }
+
+ if (list) {
+ display_members ((const char *const *)grp->gr_mem);
+ } else if (NULL != adduser) {
+ add_user (adduser, grp);
+ } else if (NULL != deluser) {
+ remove_user (deluser, grp);
+ } else if (purge) {
+ purge_members (grp);
+ }
+
+ close_files ();
+
+ exit (EXIT_SUCCESS);
+}
+