2 files changed, 81 insertions, 33 deletions

diff --git a/include/usage.h b/include/usage.h
index 9b5f484c1..d60a4dc78 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -10,9 +10,13 @@
 #define adduser_full_usage \
         "Adds a user to the system" \
         "Options:\n" \
-            "\t-h\t\thome directory\n" \
-            "\t-s\t\tshell\n" \
-            "\t-g\t\tGECOS string\n"
+            "\t-h DIR\t\tAssign home directory DIR\n" \
+            "\t-g GECOS\t\tAssign gecos field GECOS\n" \
+            "\t-s SHELL\t\tAssign login shell SHELL\n" \
+            "\t-G\t\tAdd the user to existing group GROUP\n" \
+            "\t-S\t\tcreate a system user (ignored)\n" \
+            "\t-D\t\tDo not assign a password (logins still possible via ssh)\n" \
+            "\t-H\t\tDo not create the home directory\n"
 
 #define adjtimex_trivial_usage \
         "[-q] [-o offset] [-f frequency] [-p timeconstant] [-t tick]"
diff --git a/loginutils/adduser.c b/loginutils/adduser.c
index 6784d32cc..41dc9f019 100644
--- a/loginutils/adduser.c
+++ b/loginutils/adduser.c
@@ -21,6 +21,9 @@
  *
  */
 
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
 #include <errno.h>
 #include <fcntl.h>
 #include <stdarg.h>
@@ -29,6 +32,7 @@
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
+#include <getopt.h>
 #include <sys/param.h>
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -89,21 +93,23 @@ static int passwd_study(const char *filename, struct passwd *p)
                 }
         }
 
-        /* EDR check for an already existing gid */
-        while (getgrgid(p->pw_uid) != NULL)
-                p->pw_uid++;
+        if (p->pw_gid == 0) {
+                /* EDR check for an already existing gid */
+                while (getgrgid(p->pw_uid) != NULL)
+                        p->pw_uid++;
+
+                /* EDR also check for an existing group definition */
+                if (getgrnam(p->pw_name) != NULL)
+                        return 3;
 
-        /* EDR also check for an existing group definition */
-        if (getgrnam(p->pw_name) != NULL)
-                return 3;
+                /* EDR create new gid always = uid */
+                p->pw_gid = p->pw_uid;
+        }
 
         /* EDR bounds check */
         if ((p->pw_uid > max) || (p->pw_uid < min))
                 return 2;
 
-        /* EDR create new gid always = uid */
-        p->pw_gid = p->pw_uid;
-
         /* return 1; */
         return 0;
 }
@@ -127,7 +133,7 @@ static void passwd_wrapper(const char *login)
 }
 
 /* putpwent(3) remix */
-static int adduser(const char *filename, struct passwd *p)
+static int adduser(const char *filename, struct passwd *p, int makehome, int setpass)
 {
         FILE *passwd;
         int r;
@@ -135,6 +141,11 @@ static int adduser(const char *filename, struct passwd *p)
         FILE *shadow;
         struct spwd *sp;
 #endif
+        int new_group = 1;
+
+        /* if using a pre-existing group, don't create one */
+        if (p->pw_gid != 0)
+                new_group = 0;
 
         /* make sure everything is kosher and setup uid && gid */
         passwd = bb_wfopen(filename, "a");
@@ -181,29 +192,38 @@ static int adduser(const char *filename, struct passwd *p)
         }
 #endif
 
-        /* add to group */
-        /* addgroup should be responsible for dealing w/ gshadow */
-        addgroup_wrapper(p->pw_name, p->pw_gid);
+        if (new_group) {
+                /* add to group */
+                /* addgroup should be responsible for dealing w/ gshadow */
+                addgroup_wrapper(p->pw_name, p->pw_gid);
+        }
 
         /* Clear the umask for this process so it doesn't
          * * screw up the permissions on the mkdir and chown. */
         umask(0);
 
-        /* mkdir */
-        if (mkdir(p->pw_dir, 0755)) {
-                bb_perror_msg("%s", p->pw_dir);
-        }
-        /* Set the owner and group so it is owned by the new user. */
-        if (chown(p->pw_dir, p->pw_uid, p->pw_gid)) {
-                bb_perror_msg("%s", p->pw_dir);
+        if (makehome) {
+                /* mkdir */
+                if (mkdir(p->pw_dir, 0755)) {
+                        bb_perror_msg("%s", p->pw_dir);
+                }
+                /* Set the owner and group so it is owned by the new user. */
+                if (chown(p->pw_dir, p->pw_uid, p->pw_gid)) {
+                        bb_perror_msg("%s", p->pw_dir);
+                }
+                /* Now fix up the permissions to 2755. Can't do it before now
+                 * since chown will clear the setgid bit */
+                if (chmod(p->pw_dir, 02755)) {
+                        bb_perror_msg("%s", p->pw_dir);
+                }
         }
-        /* Now fix up the permissions to 2755. Can't do it before now
-         * since chown will clear the setgid bit */
-        if (chmod(p->pw_dir, 02755)) {
-                bb_perror_msg("%s", p->pw_dir);
+
+        if (setpass) {
+                /* interactively set passwd */
+                passwd_wrapper(p->pw_name);
         }
-        /* interactively set passwd */
-        passwd_wrapper(p->pw_name);
+
+        return 0;
 }
 
 
@@ -219,6 +239,9 @@ void if_i_am_not_root(void)
         }
 }
 
+#define SETPASS                         1
+#define MAKEHOME                        4
+
 /*
  * adduser will take a login_name as its first parameter.
  *
@@ -230,19 +253,29 @@ void if_i_am_not_root(void)
  * ________________________________________________________________________ */
 int adduser_main(int argc, char **argv)
 {
+        struct passwd pw;
         const char *login;
         const char *gecos = default_gecos;
         const char *home = NULL;
         const char *shell = default_shell;
-
-        struct passwd pw;
+        const char *usegroup = NULL;
+        int flags;
+        int setpass = 1;
+        int makehome = 1;
 
         /* init */
         if (argc < 2) {
                 bb_show_usage();
         }
         /* get args */
-        bb_getopt_ulflags(argc, argv, "h:g:s:", &home, &gecos, &shell);
+        flags = bb_getopt_ulflags(argc, argv, "h:g:s:G:DSH", &home, &gecos, &shell, &usegroup);
+
+        if (flags & SETPASS) {
+                setpass = 0;
+        }
+        if (flags & MAKEHOME) {
+                makehome = 0;
+        }
 
         /* got root? */
         if_i_am_not_root();
@@ -271,6 +304,17 @@ int adduser_main(int argc, char **argv)
         pw.pw_dir = (char *)home;
         pw.pw_shell = (char *)shell;
 
+        if (usegroup) {
+                /* Add user to a group that already exists */
+                struct group *g;
+
+                g = getgrnam(usegroup);
+                if (g == NULL)
+                        bb_error_msg_and_die("group %s does not exist", usegroup);
+
+                pw.pw_gid = g->gr_gid;
+        }
+
         /* grand finale */
-        return adduser(bb_path_passwd_file, &pw);
+        return adduser(bb_path_passwd_file, &pw, makehome, setpass);
 }