From 18ec03543c3731e1ea25182ef72c49ac5ec2d1c7 Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Wed, 16 Oct 2013 20:41:56 -0500 Subject: useradd, groupadd, and mkpasswd submitted by Ashwini Sharma. --- toys/pending/useradd.c | 246 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 246 insertions(+) create mode 100644 toys/pending/useradd.c (limited to 'toys/pending/useradd.c') diff --git a/toys/pending/useradd.c b/toys/pending/useradd.c new file mode 100644 index 00000000..ecfd638f --- /dev/null +++ b/toys/pending/useradd.c @@ -0,0 +1,246 @@ +/* useradd.c - add a new user + * + * Copyright 2013 Ashwini Kumar + * Copyright 2013 Kyungwan Han + * + * See http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/useradd.html + +USE_USERADD(NEWTOY(useradd, "<1>2u#<0G:s:g:h:SDH", TOYFLAG_NEEDROOT|TOYFLAG_SBIN)) +USE_USERADD(OLDTOY(adduser, useradd, OPTSTR_useradd, TOYFLAG_NEEDROOT|TOYFLAG_SBIN)) + +config USERADD + bool "useradd" + default n + help + usage: useradd [-SDH] [-hDIR] [-sSHELL] [-G GRP] [-gGECOS] [-uUID] USER [GROUP] + + Create new user, or add USER to GROUP + + -h DIR Home directory + -g GECOS GECOS field + -s SHELL Login shell + -G GRP Add user to existing group + -S Create a system user + -D Don't assign a password + -H Don't create home directory + -u UID User id +*/ + +#define FOR_useradd +#include "toys.h" + +GLOBALS( + char *dir; + char *gecos; + char *shell; + char *u_grp; + long uid; + long gid; +) + +static char* get_shell(void) +{ + char *shell = getenv("SHELL"); + + if (!shell) { + struct passwd *pw; + pw = getpwuid(getuid()); + if (pw && pw->pw_shell && pw->pw_shell[0]) + shell = pw->pw_shell; + else shell = "/bin/sh"; + } + return xstrdup(shell); +} + +/* exec_wait() function does a fork(), and exec the command, + * waits for the child to exit and return the status to parent + */ +static int exec_wait(char **args) +{ + int status = 0; + pid_t pid = fork(); + + if (!pid) xexec(args); + else if (pid > 0) waitpid(pid, &status, 0); + else perror_exit("fork failed"); + return WEXITSTATUS(status); +} + +/* create_copy_skel(), This function will create the home directory of the + * user, by copying /etc/skel/ contents to /home/. + * Then change the ownership of home dir to the UID and GID of new user, + * and Mode to 0700, i.e. rwx------ for user. + */ +static void create_copy_skel(char *skel, char *hdir) +{ + char *args[5]; + struct stat sb; + + if (toys.optflags & FLAG_H) return; + + umask(0); + args[4] = NULL; + if (stat(hdir, &sb)) { + args[0] = "cp"; + args[1] = "-R"; + args[2] = skel; + args[3] = hdir; + // Copy /etc/skel to home dir + toys.exitval = exec_wait(args); + + args[0] = "chown"; + args[1] = "-R"; + args[2] = xmsprintf("%u:%u", TT.uid, TT.gid); + args[3] = hdir; + //Change ownership to that of UID and GID of new user + toys.exitval = exec_wait(args); + + } else xprintf("Warning: home directory for the user already exists\n" + "Not copying any file from skel directory into it.\n"); + + if (chown(hdir, TT.uid, TT.gid) || chmod(hdir, 0700)) + perror_exit("chown/chmod failed for '%s'", hdir); +} + +/* Add a new group to the system, if UID is given then that is validated + * to be free, else a free UID is choosen by self. + * SYSTEM IDs are considered in the range 100 ... 999 + * add_user(), add a new entry in /etc/passwd, /etc/shadow files + */ +static void new_user() +{ + struct passwd pwd; + char *entry, *args[4]; + int max = INT_MAX; + + pwd.pw_name = *toys.optargs; + pwd.pw_passwd = (char *)"x"; + if (toys.optflags & FLAG_g) pwd.pw_gecos = TT.gecos; + else pwd.pw_gecos = "Linux User,"; + if (toys.optflags & FLAG_h) pwd.pw_dir = TT.dir; + else pwd.pw_dir = xmsprintf("/home/%s", *toys.optargs); + if (toys.optflags & FLAG_s) pwd.pw_shell = TT.shell; + else pwd.pw_shell = get_shell(); + + if (toys.optflags & FLAG_u) { + if (TT.uid > INT_MAX) error_exit("uid should be less than '%d' ", INT_MAX); + if (getpwuid(TT.uid)) error_exit("user '%ld' is in use", TT.uid); + pwd.pw_uid = TT.uid; + } else { + if (toys.optflags & FLAG_S) { + TT.uid = SYS_FIRST_ID; + max = SYS_LAST_ID; + } else { + TT.uid = SYS_LAST_ID + 1; //i.e. starting from 1000 + max = 60000; // as per config file on Linux desktop + } + //find unused uid + while (TT.uid <= max) { + if (!getpwuid(TT.uid)) break; + if (TT.uid == max) error_exit("no more free uids left"); + TT.uid++; + } + pwd.pw_uid = TT.uid; + } + + if (toys.optflags & FLAG_G) { + struct group *gr = getgrnam(TT.u_grp); + if (!gr) error_exit("The group '%s' doesn't exist", TT.u_grp); + TT.gid = gr->gr_gid; + } else { + // Set the GID for the user, if not specified + if (toys.optflags & FLAG_S) { + TT.gid = SYS_FIRST_ID; + max = SYS_LAST_ID; + } else TT.gid = ((TT.uid > SYS_LAST_ID) ? TT.uid : SYS_LAST_ID + 1); + if (getgrnam(pwd.pw_name)) error_exit("group '%s' is in use", pwd.pw_name); + //find unused gid + while (TT.gid <= max) { + if (!getgrgid(TT.gid)) break; + if (TT.gid == max) error_exit("no more free gids left"); + TT.gid++; + } + } + pwd.pw_gid = TT.gid; + + if (!(toys.optflags & FLAG_G)) { + // Create a new group for user + //add group, invoke addgroup command + args[0] = "groupadd"; + args[1] = toys.optargs[0]; + args[2] = xmsprintf("-g%ld", pwd.pw_gid); + args[3] = NULL; + if (exec_wait(args)) error_msg("addgroup fail"); + } + + /*add user to system + * 1. add an entry to /etc/passwd and /etcshadow file + * 2. Copy /etc/skel dir contents to use home dir + * 3. update the user passwd by running 'passwd' utility + */ + + // 1. add an entry to /etc/passwd and /etc/shadow file + entry = xmsprintf("%s:%s:%ld:%ld:%s:%s:%s", pwd.pw_name, pwd.pw_passwd, + pwd.pw_uid, pwd.pw_gid, pwd.pw_gecos, pwd.pw_dir, pwd.pw_shell); + if (update_password("/etc/passwd", pwd.pw_name, entry)) error_exit("updating passwd file failed"); + free(entry); + + if (toys.optflags & FLAG_S) + entry = xmsprintf("%s:!!:%u::::::", pwd.pw_name, + (unsigned)(time(NULL))/(24*60*60)); //passwd is not set initially + else entry = xmsprintf("%s:!!:%u:%ld:%ld:%ld:::", pwd.pw_name, + (unsigned)(time(NULL))/(24*60*60), 0, 99999, 7); //passwd is not set initially + update_password("/etc/shadow", pwd.pw_name, entry); + free(entry); + + //2. craete home dir & copy skel dir to home + if (!(toys.optflags & FLAG_S)) create_copy_skel("/etc/skel", pwd.pw_dir); + + //3. update the user passwd by running 'passwd' utility + if (!(toys.optflags & FLAG_D)) { + args[0] = "passwd"; + args[1] = pwd.pw_name; + args[2] = NULL; + if (exec_wait(args)) error_exit("changing user passwd failed"); + } + if (toys.optflags & FLAG_G) { + /*add user to the existing group, invoke addgroup command */ + args[0] = "groupadd"; + args[1] = toys.optargs[0]; + args[2] = TT.u_grp; + args[3] = NULL; + if (exec_wait(args)) error_exit("adding user to group Failed"); + } +} + +/* Entry point for useradd feature + * Specifying options and User, Group at cmdline is treated as error. + * If only 2 parameters (Non-Option) are given, then User is added to the + * Group + */ +void useradd_main(void) +{ + struct passwd *pwd = NULL; + + if (toys.optflags && toys.optc == 2) { + toys.exithelp = 1; + error_exit("options, user and group can't be together"); + } + + if (toys.optc == 2) { + //add user to group + //toys.optargs[0]- user, toys.optargs[1] - group + char *args[4]; + args[0] = "groupadd"; + args[1] = toys.optargs[0]; + args[2] = toys.optargs[1]; + args[3] = NULL; + toys.exitval = exec_wait(args); + } else { //new user to be created + // investigate the user to be created + if ((pwd = getpwnam(*toys.optargs))) + error_exit("user '%s' is in use", *toys.optargs); + is_valid_username(*toys.optargs); //validate the user name + new_user(); + } +} -- cgit v1.2.3