root/usr.sbin/pw/pw_user.c
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (C) 1996
 *      David L. Nugent.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL DAVID L. NUGENT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * 
 */

#include <sys/param.h>
#include <sys/wait.h>

#include <assert.h>
#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <pwd.h>
#include <libutil.h>
#include <login_cap.h>
#include <paths.h>
#include <string.h>
#include <sysexits.h>
#include <termios.h>
#include <unistd.h>
#include <spawn.h>

#include "pw.h"
#include "bitmap.h"
#include "psdate.h"

#define LOGNAMESIZE (MAXLOGNAME-1)

extern char **environ;
static          char locked_str[] = "*LOCKED*";

static struct passwd fakeuser = {
        "nouser",
        "*",
        -1,
        -1,
        0,
        "",
        "User &",
        "/nonexistent",
        "/bin/sh",
        0,
        0
};

static int       print_user(struct passwd *pwd, bool pretty, bool v7);
static uid_t     pw_uidpolicy(struct userconf *cnf, intmax_t id);
static uid_t     pw_gidpolicy(struct userconf *cnf, char *grname, char *nam,
    gid_t prefer, bool dryrun);
static char     *pw_homepolicy(struct userconf * cnf, char *homedir,
    const char *user);
static char     *pw_shellpolicy(struct userconf * cnf);
static char     *pw_password(struct userconf * cnf, char const * user);
static char     *shell_path(char const * path, char *shells[], char *sh);
static void     rmat(uid_t uid);

static void
mkdir_home_parents(int dfd, const char *dir)
{
        struct stat st;
        char *dirs, *tmp;
        mode_t pumask;

        pumask = umask(0);
        umask(pumask);

        if (*dir != '/')
                errx(EX_DATAERR, "invalid base directory for home '%s'", dir);
        dir++;

        if (fstatat(dfd, dir, &st, 0) != -1) {
                if (S_ISDIR(st.st_mode))
                        return;
                errx(EX_OSFILE, "root home `/%s' is not a directory", dir);
        }

        dirs = strdup(dir);
        if (dirs == NULL)
                errx(EX_UNAVAILABLE, "out of memory");

        tmp = strrchr(dirs, '/');
        if (tmp == NULL) {
                free(dirs);
                return;
        }
        tmp[0] = '\0';

        tmp = dirs;
        if (fstatat(dfd, dirs, &st, 0) == -1) {
                while ((tmp = strchr(tmp + 1, '/')) != NULL) {
                        *tmp = '\0';
                        if (fstatat(dfd, dirs, &st, 0) == -1) {
                                if (mkdirat(dfd, dirs, _DEF_DIRMODE) == -1)
                                        err(EX_OSFILE,
                                    "'%s' (home parent) is not a directory",
                                            dirs);
                                if (fchownat(dfd, dirs, 0, 0, 0) != 0)
                                        warn("chown(%s)", dirs);
                                metalog_emit(dirs,
                                    (_DEF_DIRMODE | S_IFDIR) & ~pumask, 0, 0,
                                    0);
                        }
                        *tmp = '/';
                }
        }
        if (fstatat(dfd, dirs, &st, 0) == -1) {
                if (mkdirat(dfd, dirs, _DEF_DIRMODE) == -1)
                        err(EX_OSFILE,  "'%s' (home parent) is not a directory", dirs);
                if (fchownat(dfd, dirs, 0, 0, 0) != 0)
                        warn("chown(%s)", dirs);
                metalog_emit(dirs, (_DEF_DIRMODE | S_IFDIR) & ~pumask, 0, 0, 0);
        }

        free(dirs);
}

static void
create_and_populate_homedir(struct userconf *cnf, struct passwd *pwd,
    const char *skeldir, mode_t homemode, bool update)
{
        int skelfd = -1;

        /* Create home parents directories */
        mkdir_home_parents(conf.rootfd, pwd->pw_dir);

        if (skeldir != NULL && *skeldir != '\0') {
                if (*skeldir == '/')
                        skeldir++;
                skelfd = openat(conf.rootfd, skeldir, O_DIRECTORY|O_CLOEXEC);
        }

        copymkdir(conf.rootfd, pwd->pw_dir, skelfd, homemode, pwd->pw_uid,
            pwd->pw_gid, 0);
        pw_log(cnf, update ? M_MODIFY : M_ADD, W_USER, "%s(%ju) home %s made",
            pwd->pw_name, (uintmax_t)pwd->pw_uid, pwd->pw_dir);
}

static int
pw_set_passwd(struct passwd *pwd, int fd, bool precrypted, bool update)
{
        int              b, istty;
        struct termios   t, n;
        login_cap_t     *lc;
        char            line[_PASSWORD_LEN+1];
        char            *p;

        if (fd == '-') {
                if (!pwd->pw_passwd || *pwd->pw_passwd != '*') {
                        pwd->pw_passwd = "*";   /* No access */
                        return (1);
                }
                return (0);
        }

        if ((istty = isatty(fd))) {
                if (tcgetattr(fd, &t) == -1)
                        istty = 0;
                else {
                        n = t;
                        n.c_lflag &= ~(ECHO);
                        tcsetattr(fd, TCSANOW, &n);
                        printf("%s%spassword for user %s:",
                            update ? "new " : "",
                            precrypted ? "encrypted " : "",
                            pwd->pw_name);
                        fflush(stdout);
                }
        }
        b = read(fd, line, sizeof(line) - 1);
        if (istty) {    /* Restore state */
                tcsetattr(fd, TCSANOW, &t);
                fputc('\n', stdout);
                fflush(stdout);
        }

        if (b < 0)
                err(EX_IOERR, "-%c file descriptor",
                    precrypted ? 'H' : 'h');
        line[b] = '\0';
        if ((p = strpbrk(line, "\r\n")) != NULL)
                *p = '\0';
        if (!*line)
                errx(EX_DATAERR, "empty password read on file descriptor %d",
                    fd);
        if (precrypted) {
                if (strchr(line, ':') != NULL)
                        errx(EX_DATAERR, "bad encrypted password");
                pwd->pw_passwd = strdup(line);
        } else {
                lc = login_getpwclass(pwd);
                if (lc == NULL ||
                                login_setcryptfmt(lc, "sha512", NULL) == NULL)
                        warn("setting crypt(3) format");
                login_close(lc);
                pwd->pw_passwd = pw_pwcrypt(line);
        }
        return (1);
}

static void
perform_chgpwent(const char *name, struct passwd *pwd, char *nispasswd)
{
        int rc;
        struct passwd *nispwd;

        /* duplicate for nis so that chgpwent is not modifying before NIS */
        if (nispasswd && *nispasswd == '/')
                nispwd = pw_dup(pwd);

        rc = chgpwent(name, pwd);
        if (rc == -1)
                errx(EX_IOERR, "user '%s' does not exist (NIS?)", pwd->pw_name);
        else if (rc != 0)
                err(EX_IOERR, "passwd file update");

        if (nispasswd && *nispasswd == '/') {
                rc = chgnispwent(nispasswd, name, nispwd);
                if (rc == -1)
                        warn("User '%s' not found in NIS passwd", pwd->pw_name);
                else if (rc != 0)
                        warn("NIS passwd update");
                /* NOTE: NIS-only update errors are not fatal */
        }
}

static void
pw_check_root(void)
{
        if (!conf.altroot && geteuid() != 0)
                errx(EX_NOPERM, "you must be root");
}

/*
 * The M_LOCK and M_UNLOCK functions simply add or remove
 * a "*LOCKED*" prefix from in front of the password to
 * prevent it decoding correctly, and therefore prevents
 * access. Of course, this only prevents access via
 * password authentication (not ssh, kerberos or any
 * other method that does not use the UNIX password) but
 * that is a known limitation.
 */
static int
pw_userlock(char *arg1, int mode)
{
        struct passwd *pwd = NULL;
        char *passtmp = NULL;
        char *name;
        bool locked = false;
        uid_t id = (uid_t)-1;

        pw_check_root();

        if (arg1 == NULL)
                errx(EX_DATAERR, "username or id required");

        name = arg1;
        if (arg1[strspn(name, "0123456789")] == '\0')
                id = pw_checkid(name, UID_MAX);

        pwd = GETPWNAM(pw_checkname(name, 0));
        if (pwd == NULL && id != (uid_t)-1) {
                pwd = GETPWUID(id);
                if (pwd != NULL)
                        name = pwd->pw_name;
        }
        if (pwd == NULL) {
                if (id == (uid_t)-1)
                        errx(EX_NOUSER, "no such name or uid `%ju'", (uintmax_t) id);
                errx(EX_NOUSER, "no such user `%s'", name);
        }

        if (name == NULL)
                name = pwd->pw_name;

        if (strncmp(pwd->pw_passwd, locked_str, sizeof(locked_str) -1) == 0)
                locked = true;
        if (mode == M_LOCK && locked)
                errx(EX_DATAERR, "user '%s' is already locked", pwd->pw_name);
        if (mode == M_UNLOCK && !locked)
                errx(EX_DATAERR, "user '%s' is not locked", pwd->pw_name);

        if (mode == M_LOCK) {
                asprintf(&passtmp, "%s%s", locked_str, pwd->pw_passwd);
                if (passtmp == NULL)    /* disaster */
                        errx(EX_UNAVAILABLE, "out of memory");
                pwd->pw_passwd = passtmp;
        } else {
                pwd->pw_passwd += sizeof(locked_str)-1;
        }

        perform_chgpwent(name, pwd, NULL);
        free(passtmp);

        return (EXIT_SUCCESS);
}

static uid_t
pw_uidpolicy(struct userconf * cnf, intmax_t id)
{
        struct passwd  *pwd;
        struct bitmap   bm;
        uid_t           uid = (uid_t) - 1;

        /*
         * Check the given uid, if any
         */
        if (id >= 0) {
                uid = (uid_t) id;

                if ((pwd = GETPWUID(uid)) != NULL && conf.checkduplicate)
                        errx(EX_DATAERR, "uid `%ju' has already been allocated",
                            (uintmax_t)pwd->pw_uid);
                return (uid);
        }
        /*
         * We need to allocate the next available uid under one of
         * two policies a) Grab the first unused uid b) Grab the
         * highest possible unused uid
         */
        if (cnf->min_uid >= cnf->max_uid) {     /* Sanity
                                                 * claus^H^H^H^Hheck */
                cnf->min_uid = 1000;
                cnf->max_uid = 32000;
        }
        bm = bm_alloc(cnf->max_uid - cnf->min_uid + 1);

        /*
         * Now, let's fill the bitmap from the password file
         */
        SETPWENT();
        while ((pwd = GETPWENT()) != NULL)
                if (pwd->pw_uid >= (uid_t) cnf->min_uid && pwd->pw_uid <= (uid_t) cnf->max_uid)
                        bm_setbit(&bm, pwd->pw_uid - cnf->min_uid);
        ENDPWENT();

        /*
         * Then apply the policy, with fallback to reuse if necessary
         */
        if (cnf->reuse_uids || (uid = (uid_t) (bm_lastset(&bm) + cnf->min_uid + 1)) > cnf->max_uid)
                uid = (uid_t) (bm_firstunset(&bm) + cnf->min_uid);

        /*
         * Another sanity check
         */
        if (uid < cnf->min_uid || uid > cnf->max_uid)
                errx(EX_SOFTWARE, "unable to allocate a new uid - range fully used");
        bm_dealloc(&bm);
        return (uid);
}

static uid_t
pw_gidpolicy(struct userconf *cnf, char *grname, char *nam, gid_t prefer, bool dryrun)
{
        struct group   *grp;
        gid_t           gid = (uid_t) - 1;

        /*
         * Check the given gid, if any
         */
        SETGRENT();
        if (grname) {
                if ((grp = GETGRNAM(grname)) == NULL) {
                        gid = pw_checkid(grname, GID_MAX);
                        grp = GETGRGID(gid);
                }
                gid = grp->gr_gid;
        } else if ((grp = GETGRNAM(nam)) != NULL) {
                gid = grp->gr_gid;  /* Already created? Use it anyway... */
        } else {
                intmax_t                grid = -1;

                /*
                 * We need to auto-create a group with the user's name. We
                 * can send all the appropriate output to our sister routine
                 * bit first see if we can create a group with gid==uid so we
                 * can keep the user and group ids in sync. We purposely do
                 * NOT check the gid range if we can force the sync. If the
                 * user's name dups an existing group, then the group add
                 * function will happily handle that case for us and exit.
                 */
                if (GETGRGID(prefer) == NULL)
                        grid = prefer;
                if (dryrun) {
                        gid = pw_groupnext(cnf, true);
                } else {
                        if (grid == -1)
                                grid =  pw_groupnext(cnf, true);
                        groupadd(cnf, nam, grid, NULL, -1, false, false, false);
                        if ((grp = GETGRNAM(nam)) != NULL)
                                gid = grp->gr_gid;
                }
        }
        ENDGRENT();
        return (gid);
}

static char *
pw_homepolicy(struct userconf * cnf, char *homedir, const char *user)
{
        static char     home[128];

        if (homedir)
                return (homedir);

        if (cnf->home == NULL || *cnf->home == '\0')
                errx(EX_CONFIG, "no base home directory set");
        snprintf(home, sizeof(home), "%s/%s", cnf->home, user);

        return (home);
}

static char *
shell_path(char const * path, char *shells[], char *sh)
{
        if (sh != NULL && (*sh == '/' || *sh == '\0'))
                return sh;      /* specified full path or forced none */
        else {
                char           *p;
                char            paths[_UC_MAXLINE];

                /*
                 * We need to search paths
                 */
                strlcpy(paths, path, sizeof(paths));
                for (p = strtok(paths, ": \t\r\n"); p != NULL; p = strtok(NULL, ": \t\r\n")) {
                        int             i;
                        static char     shellpath[256];

                        if (sh != NULL) {
                                snprintf(shellpath, sizeof(shellpath), "%s/%s", p, sh);
                                if (access(shellpath, X_OK) == 0)
                                        return shellpath;
                        } else
                                for (i = 0; i < _UC_MAXSHELLS && shells[i] != NULL; i++) {
                                        snprintf(shellpath, sizeof(shellpath), "%s/%s", p, shells[i]);
                                        if (access(shellpath, X_OK) == 0)
                                                return shellpath;
                                }
                }
                if (sh != NULL)
                        errx(EX_OSFILE, "can't find shell `%s' in shell paths", sh);
                errx(EX_CONFIG, "no default shell available or defined");
                return NULL;
        }
}

static char *
pw_shellpolicy(struct userconf * cnf)
{

        return shell_path(cnf->shelldir, cnf->shells, cnf->shell_default);
}

#define SALTSIZE        32

static char const chars[] = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ./";

char *
pw_pwcrypt(char *password)
{
        int             i;
        char            salt[SALTSIZE + 1];
        char            *cryptpw;
        static char     buf[256];
        size_t          pwlen;

        /*
         * Calculate a salt value
         */
        for (i = 0; i < SALTSIZE; i++)
                salt[i] = chars[arc4random_uniform(sizeof(chars) - 1)];
        salt[SALTSIZE] = '\0';

        cryptpw = crypt(password, salt);
        if (cryptpw == NULL)
                errx(EX_CONFIG, "crypt(3) failure");
        pwlen = strlcpy(buf, cryptpw, sizeof(buf));
        assert(pwlen < sizeof(buf));
        return (buf);
}

static char *
pw_password(struct userconf * cnf, char const * user)
{
        int             i, l;
        char            pwbuf[32];

        switch (cnf->default_password) {
        case P_NONE:            /* No password at all! */
                return "";
        case P_RANDOM:                  /* Random password */
                l = (arc4random() % 8 + 8);     /* 8 - 16 chars */
                for (i = 0; i < l; i++)
                        pwbuf[i] = chars[arc4random_uniform(sizeof(chars)-1)];
                pwbuf[i] = '\0';

                /*
                 * We give this information back to the user
                 */
                if (conf.fd == -1) {
                        if (isatty(STDOUT_FILENO))
                                printf("Password for '%s' is: ", user);
                        printf("%s\n", pwbuf);
                        fflush(stdout);
                }
                break;
        case P_YES:             /* user's name */
                strlcpy(pwbuf, user, sizeof(pwbuf));
                break;
        case P_NO:              /* No login - default */
                                /* FALLTHROUGH */
        default:
                return "*";
        }
        return pw_pwcrypt(pwbuf);
}

static int
print_user(struct passwd * pwd, bool pretty, bool v7)
{
        int             j;
        char           *p;
        struct group   *grp = GETGRGID(pwd->pw_gid);
        char            uname[60] = "User &", office[60] = "[None]",
                        wphone[60] = "[None]", hphone[60] = "[None]";
        char            acexpire[32] = "[None]", pwexpire[32] = "[None]";
        struct tm *    tptr;

        if (!pretty) {
                p = v7 ? pw_make_v7(pwd) : pw_make(pwd);
                printf("%s\n", p);
                free(p);
                return (EXIT_SUCCESS);
        }

        if ((p = strtok(pwd->pw_gecos, ",")) != NULL) {
                strlcpy(uname, p, sizeof(uname));
                if ((p = strtok(NULL, ",")) != NULL) {
                        strlcpy(office, p, sizeof(office));
                        if ((p = strtok(NULL, ",")) != NULL) {
                                strlcpy(wphone, p, sizeof(wphone));
                                if ((p = strtok(NULL, "")) != NULL) {
                                        strlcpy(hphone, p, sizeof(hphone));
                                }
                        }
                }
        }
        /*
         * Handle '&' in gecos field
         */
        if ((p = strchr(uname, '&')) != NULL) {
                int             l = strlen(pwd->pw_name);
                int             m = strlen(p);

                memmove(p + l, p + 1, m);
                memmove(p, pwd->pw_name, l);
                *p = (char) toupper((unsigned char)*p);
        }
        if (pwd->pw_expire > (time_t)0 && (tptr = localtime(&pwd->pw_expire)) != NULL)
                strftime(acexpire, sizeof acexpire, "%c", tptr);
        if (pwd->pw_change > (time_t)0 && (tptr = localtime(&pwd->pw_change)) != NULL)
                strftime(pwexpire, sizeof pwexpire, "%c", tptr);
        printf("Login Name: %-15s   #%-12ju Group: %-15s   #%ju\n"
               " Full Name: %s\n"
               "      Home: %-26.26s      Class: %s\n"
               "     Shell: %-26.26s     Office: %s\n"
               "Work Phone: %-26.26s Home Phone: %s\n"
               "Acc Expire: %-26.26s Pwd Expire: %s\n",
               pwd->pw_name, (uintmax_t)pwd->pw_uid,
               grp ? grp->gr_name : "(invalid)", (uintmax_t)pwd->pw_gid,
               uname, pwd->pw_dir, pwd->pw_class,
               pwd->pw_shell, office, wphone, hphone,
               acexpire, pwexpire);
        SETGRENT();
        j = 0;
        while ((grp=GETGRENT()) != NULL) {
                int     i = 0;
                if (grp->gr_mem != NULL) {
                        while (grp->gr_mem[i] != NULL) {
                                if (strcmp(grp->gr_mem[i], pwd->pw_name)==0) {
                                        printf(j++ == 0 ? "    Groups: %s" : ",%s", grp->gr_name);
                                        break;
                                }
                                ++i;
                        }
                }
        }
        ENDGRENT();
        printf("%s", j ? "\n" : "");
        return (EXIT_SUCCESS);
}

char *
pw_checkname(char *name, int gecos)
{
        char showch[8];
        const char *badchars, *ch, *showtype;
        int reject;

        ch = name;
        reject = 0;
        if (gecos) {
                /* See if the name is valid as a gecos (comment) field. */
                badchars = ":";
                showtype = "gecos field";
        } else {
                /* See if the name is valid as a userid or group. */
                badchars = " ,\t:+&#%$^()!@~*?<>=|\\/\";";
                showtype = "userid/group name";
                /* Userids and groups can not have a leading '-'. */
                if (*ch == '-')
                        reject = 1;
        }
        if (!reject) {
                while (*ch) {
                        if (strchr(badchars, *ch) != NULL ||
                            (!gecos && *ch < ' ') ||
                            *ch == 127) {
                                reject = 1;
                                break;
                        }
                        /* 8-bit characters are only allowed in GECOS fields */
                        if (!gecos && (*ch & 0x80)) {
                                reject = 1;
                                break;
                        }
                        ch++;
                }
        }
        /*
         * A `$' is allowed as the final character for userids and groups,
         * mainly for the benefit of samba.
         */
        if (reject && !gecos) {
                if (*ch == '$' && *(ch + 1) == '\0') {
                        reject = 0;
                        ch++;
                }
        }
        if (reject) {
                snprintf(showch, sizeof(showch), (*ch >= ' ' && *ch < 127)
                    ? "`%c'" : "0x%02x", *ch);
                errx(EX_DATAERR, "invalid character %s at position %td in %s",
                    showch, (ch - name), showtype);
        }
        if (!gecos && (ch - name) > LOGNAMESIZE)
                errx(EX_USAGE, "name too long `%s' (max is %d)", name,
                    LOGNAMESIZE);

        return (name);
}

static void
rmat(uid_t uid)
{
        DIR            *d = opendir("/var/at/jobs");

        if (d != NULL) {
                struct dirent  *e;

                while ((e = readdir(d)) != NULL) {
                        struct stat     st;
                        pid_t           pid;

                        if (strncmp(e->d_name, ".lock", 5) != 0 &&
                            stat(e->d_name, &st) == 0 &&
                            !S_ISDIR(st.st_mode) &&
                            st.st_uid == uid) {
                                const char *argv[] = {
                                        "/usr/sbin/atrm",
                                        e->d_name,
                                        NULL
                                };
                                if (posix_spawn(&pid, argv[0], NULL, NULL,
                                    (char *const *) argv, environ)) {
                                        warn("Failed to execute '%s %s'",
                                            argv[0], argv[1]);
                                } else
                                        (void) waitpid(pid, NULL, 0);
                        }
                }
                closedir(d);
        }
}

int
pw_user_next(int argc, char **argv, char *name __unused)
{
        struct userconf *cnf = NULL;
        const char *cfg = NULL;
        int ch;
        bool quiet = false;
        uid_t next;

        while ((ch = getopt(argc, argv, "C:q")) != -1) {
                switch (ch) {
                case 'C':
                        cfg = optarg;
                        break;
                case 'q':
                        quiet = true;
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if (argc > 0)
                usage();

        if (quiet)
                freopen(_PATH_DEVNULL, "w", stderr);

        cnf = get_userconfig(cfg);

        next = pw_uidpolicy(cnf, -1);

        printf("%ju:", (uintmax_t)next);
        pw_groupnext(cnf, quiet);

        return (EXIT_SUCCESS);
}

int
pw_user_show(int argc, char **argv, char *arg1)
{
        struct passwd *pwd = NULL;
        char *name = NULL;
        intmax_t id = -1;
        int ch;
        bool all = false;
        bool pretty = false;
        bool force = false;
        bool v7 = false;
        bool quiet = false;

        if (arg1 != NULL) {
                if (arg1[strspn(arg1, "0123456789")] == '\0')
                        id = pw_checkid(arg1, UID_MAX);
                else
                        name = arg1;
        }

        while ((ch = getopt(argc, argv, "C:qn:u:FPa7")) != -1) {
                switch (ch) {
                case 'C':
                        /* ignore compatibility */
                        break;
                case 'q':
                        quiet = true;
                        break;
                case 'n':
                        name = optarg;
                        break;
                case 'u':
                        id = pw_checkid(optarg, UID_MAX);
                        break;
                case 'F':
                        force = true;
                        break;
                case 'P':
                        pretty = true;
                        break;
                case 'a':
                        all = true;
                        break;
                case '7':
                        v7 = true;
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if (argc > 0)
                usage();

        if (quiet)
                freopen(_PATH_DEVNULL, "w", stderr);

        if (all) {
                SETPWENT();
                while ((pwd = GETPWENT()) != NULL)
                        print_user(pwd, pretty, v7);
                ENDPWENT();
                return (EXIT_SUCCESS);
        }

        if (id < 0 && name == NULL)
                errx(EX_DATAERR, "username or id required");

        pwd = (name != NULL) ? GETPWNAM(pw_checkname(name, 0)) : GETPWUID(id);
        if (pwd == NULL) {
                if (force) {
                        pwd = &fakeuser;
                } else {
                        if (name == NULL)
                                errx(EX_NOUSER, "no such uid `%ju'",
                                    (uintmax_t) id);
                        errx(EX_NOUSER, "no such user `%s'", name);
                }
        }

        return (print_user(pwd, pretty, v7));
}

int
pw_user_del(int argc, char **argv, char *arg1)
{
        struct userconf *cnf = NULL;
        struct passwd *pwd = NULL;
        struct group *gr, *grp;
        char *name = NULL;
        char grname[MAXLOGNAME];
        char *nispasswd = NULL;
        char file[MAXPATHLEN];
        char home[MAXPATHLEN];
        const char *cfg = NULL;
        struct stat st;
        intmax_t id = -1;
        int ch, rc;
        bool nis = false;
        bool deletehome = false;
        bool quiet = false;

        if (arg1 != NULL) {
                if (arg1[strspn(arg1, "0123456789")] == '\0')
                        id = pw_checkid(arg1, UID_MAX);
                else
                        name = arg1;
        }

        while ((ch = getopt(argc, argv, "C:qn:u:rYy:")) != -1) {
                switch (ch) {
                case 'C':
                        cfg = optarg;
                        break;
                case 'q':
                        quiet = true;
                        break;
                case 'n':
                        name = optarg;
                        break;
                case 'u':
                        id = pw_checkid(optarg, UID_MAX);
                        break;
                case 'r':
                        deletehome = true;
                        break;
                case 'y':
                        nispasswd = optarg;
                        break;
                case 'Y':
                        nis = true;
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if (argc > 0)
                usage();

        if (quiet)
                freopen(_PATH_DEVNULL, "w", stderr);

        if (id < 0 && name == NULL)
                errx(EX_DATAERR, "username or id required");

        cnf = get_userconfig(cfg);

        if (nispasswd == NULL)
                nispasswd = cnf->nispasswd;

        pwd = (name != NULL) ? GETPWNAM(pw_checkname(name, 0)) : GETPWUID(id);
        if (pwd == NULL) {
                if (name == NULL)
                        errx(EX_NOUSER, "no such uid `%ju'", (uintmax_t) id);
                errx(EX_NOUSER, "no such user `%s'", name);
        }

        if (PWF._altdir == PWF_REGULAR &&
            ((pwd->pw_fields & _PWF_SOURCE) != _PWF_FILES)) {
                if ((pwd->pw_fields & _PWF_SOURCE) == _PWF_NIS) {
                        if (!nis && nispasswd && *nispasswd != '/')
                                errx(EX_NOUSER, "Cannot remove NIS user `%s'",
                                    name);
                } else {
                        errx(EX_NOUSER, "Cannot remove non local user `%s'",
                            name);
                }
        }

        id = pwd->pw_uid;
        if (name == NULL)
                name = pwd->pw_name;

        if (strcmp(pwd->pw_name, "root") == 0)
                errx(EX_DATAERR, "cannot remove user 'root'");

        if (!PWALTDIR()) {
                /* Remove crontabs */
                snprintf(file, sizeof(file), "/var/cron/tabs/%s", pwd->pw_name);
                if (access(file, F_OK) == 0) {
                        const char *argv[] = {
                                "crontab",
                                "-u",
                                pwd->pw_name,
                                "-r",
                                NULL
                        };
                        pid_t pid;

                        if (posix_spawnp(&pid, argv[0], NULL, NULL,
                                                (char *const *) argv, environ)) {
                                warn("Failed to execute '%s %s'",
                                                argv[0], argv[1]);
                        } else
                                (void) waitpid(pid, NULL, 0);
                }
        }

        /*
         * Save these for later, since contents of pwd may be
         * invalidated by deletion
         */
        snprintf(file, sizeof(file), "%s/%s", _PATH_MAILDIR, pwd->pw_name);
        strlcpy(home, pwd->pw_dir, sizeof(home));
        gr = GETGRGID(pwd->pw_gid);
        if (gr != NULL)
                strlcpy(grname, gr->gr_name, LOGNAMESIZE);
        else
                grname[0] = '\0';

        rc = delpwent(pwd);
        if (rc == -1)
                err(EX_IOERR, "user '%s' does not exist", pwd->pw_name);
        else if (rc != 0)
                err(EX_IOERR, "passwd update");

        if (nis && nispasswd && *nispasswd=='/') {
                rc = delnispwent(nispasswd, name);
                if (rc == -1)
                        warnx("WARNING: user '%s' does not exist in NIS passwd",
                            pwd->pw_name);
                else if (rc != 0)
                        warn("WARNING: NIS passwd update");
        }

        grp = GETGRNAM(name);
        if (grp != NULL &&
            (grp->gr_mem == NULL || *grp->gr_mem == NULL) &&
            strcmp(name, grname) == 0)
                delgrent(GETGRNAM(name));
        SETGRENT();
        while ((grp = GETGRENT()) != NULL) {
                int i, j;
                char group[MAXLOGNAME];
                if (grp->gr_mem == NULL)
                        continue;

                for (i = 0; grp->gr_mem[i] != NULL; i++) {
                        if (strcmp(grp->gr_mem[i], name) != 0)
                                continue;

                        for (j = i; grp->gr_mem[j] != NULL; j++)
                                grp->gr_mem[j] = grp->gr_mem[j+1];
                        strlcpy(group, grp->gr_name, MAXLOGNAME);
                        chggrent(group, grp);
                }
        }
        ENDGRENT();

        pw_log(cnf, M_DELETE, W_USER, "%s(%ju) account removed", name,
            (uintmax_t)id);

        /* Remove mail file */
        if (PWALTDIR() != PWF_ALT)
                unlinkat(conf.rootfd, file + 1, 0);

        /* Remove at jobs */
        if (!PWALTDIR() && getpwuid(id) == NULL)
                rmat(id);

        /* Remove home directory and contents */
        if (PWALTDIR() != PWF_ALT && deletehome && *home == '/' &&
            GETPWUID(id) == NULL &&
            fstatat(conf.rootfd, home + 1, &st, 0) != -1) {
                rm_r(conf.rootfd, home, id);
                pw_log(cnf, M_DELETE, W_USER, "%s(%ju) home '%s' %s"
                    "removed", name, (uintmax_t)id, home,
                     fstatat(conf.rootfd, home + 1, &st, 0) == -1 ? "" : "not "
                     "completely ");
        }

        return (EXIT_SUCCESS);
}

int
pw_user_lock(int argc, char **argv, char *arg1)
{
        int ch;

        while ((ch = getopt(argc, argv, "Cq")) != -1) {
                switch (ch) {
                case 'C':
                case 'q':
                        /* compatibility */
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if (argc > 0)
                usage();

        return (pw_userlock(arg1, M_LOCK));
}

int
pw_user_unlock(int argc, char **argv, char *arg1)
{
        int ch;

        while ((ch = getopt(argc, argv, "Cq")) != -1) {
                switch (ch) {
                case 'C':
                case 'q':
                        /* compatibility */
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if (argc > 0)
                usage();

        return (pw_userlock(arg1, M_UNLOCK));
}

static struct group *
group_from_name_or_id(char *name)
{
        const char *errstr = NULL;
        struct group *grp;
        uintmax_t id;

        if ((grp = GETGRNAM(name)) == NULL) {
                id = strtounum(name, 0, GID_MAX, &errstr);
                if (errstr)
                        errx(EX_NOUSER, "group `%s' does not exist", name);
                grp = GETGRGID(id);
                if (grp == NULL)
                        errx(EX_NOUSER, "group `%s' does not exist", name);
        }

        return (grp);
}

static void
split_groups(StringList **groups, char *groupsstr)
{
        struct group *grp;
        char *p;
        char tok[] = ", \t";

        if (*groups == NULL)
                *groups = sl_init();
        for (p = strtok(groupsstr, tok); p != NULL; p = strtok(NULL, tok)) {
                grp = group_from_name_or_id(p);
                sl_add(*groups, newstr(grp->gr_name));
        }
}

static void
validate_grname(struct userconf *cnf, char *group)
{
        struct group *grp;

        if (group == NULL || *group == '\0') {
                cnf->default_group = "";
                return;
        }
        grp = group_from_name_or_id(group);
        cnf->default_group = newstr(grp->gr_name);
}

static mode_t
validate_mode(char *mode)
{
        mode_t m;
        void *set;

        if ((set = setmode(mode)) == NULL)
                errx(EX_DATAERR, "invalid directory creation mode '%s'", mode);

        m = getmode(set, _DEF_DIRMODE);
        free(set);
        return (m);
}

static long
validate_expire(char *str, int opt)
{
        if (!numerics(str))
                errx(EX_DATAERR, "-%c argument must be numeric "
                     "when setting defaults: %s", (char)opt, str);
        return strtol(str, NULL, 0);
}

static void
mix_config(struct userconf *cmdcnf, struct userconf *cfg)
{

        if (cmdcnf->default_password < 0)
                cmdcnf->default_password = cfg->default_password;
        if (cmdcnf->reuse_uids == 0)
                cmdcnf->reuse_uids = cfg->reuse_uids;
        if (cmdcnf->reuse_gids == 0)
                cmdcnf->reuse_gids = cfg->reuse_gids;
        if (cmdcnf->nispasswd == NULL)
                cmdcnf->nispasswd = cfg->nispasswd;
        if (cmdcnf->dotdir == NULL)
                cmdcnf->dotdir = cfg->dotdir;
        if (cmdcnf->newmail == NULL)
                cmdcnf->newmail = cfg->newmail;
        if (cmdcnf->logfile == NULL)
                cmdcnf->logfile = cfg->logfile;
        if (cmdcnf->home == NULL)
                cmdcnf->home = cfg->home;
        if (cmdcnf->homemode == 0)
                cmdcnf->homemode = cfg->homemode;
        if (cmdcnf->shelldir == NULL)
                cmdcnf->shelldir = cfg->shelldir;
        if (cmdcnf->shells == NULL)
                cmdcnf->shells = cfg->shells;
        if (cmdcnf->shell_default == NULL)
                cmdcnf->shell_default = cfg->shell_default;
        if (cmdcnf->default_group == NULL)
                cmdcnf->default_group = cfg->default_group;
        if (cmdcnf->groups == NULL)
                cmdcnf->groups = cfg->groups;
        if (cmdcnf->default_class == NULL)
                cmdcnf->default_class = cfg->default_class;
        if (cmdcnf->min_uid == 0)
                cmdcnf->min_uid = cfg->min_uid;
        if (cmdcnf->max_uid == 0)
                cmdcnf->max_uid = cfg->max_uid;
        if (cmdcnf->min_gid == 0)
                cmdcnf->min_gid = cfg->min_gid;
        if (cmdcnf->max_gid == 0)
                cmdcnf->max_gid = cfg->max_gid;
        if (cmdcnf->expire_days < 0)
                cmdcnf->expire_days = cfg->expire_days;
        if (cmdcnf->password_days < 0)
                cmdcnf->password_days = cfg->password_days;
}

int
pw_user_add(int argc, char **argv, char *arg1)
{
        struct userconf *cnf, *cmdcnf;
        struct passwd *pwd;
        struct group *grp;
        struct stat st;
        char args[] = "C:qn:u:c:d:e:p:g:G:mM:k:s:oL:i:w:h:H:Db:NPy:Y";
        char line[_PASSWORD_LEN+1], path[MAXPATHLEN];
        char *gecos, *homedir, *skel, *walk, *userid, *groupid, *grname;
        char *default_passwd, *name, *p;
        const char *cfg = NULL;
        login_cap_t *lc;
        FILE *pfp, *fp;
        intmax_t id = -1;
        time_t now;
        int rc, ch, fd = -1;
        size_t i;
        bool dryrun, nis, pretty, quiet, createhome, precrypted, genconf;

        dryrun = nis = pretty = quiet = createhome = precrypted = false;
        genconf = false;
        gecos = homedir = skel = userid = groupid = default_passwd = NULL;
        grname = name = NULL;

        if ((cmdcnf = calloc(1, sizeof(struct userconf))) == NULL)
                err(EXIT_FAILURE, "calloc()");

        cmdcnf->default_password = cmdcnf->expire_days = cmdcnf->password_days = -1; 
        now = time(NULL);

        if (arg1 != NULL) {
                if (arg1[strspn(arg1, "0123456789")] == '\0')
                        id = pw_checkid(arg1, UID_MAX);
                else
                        name = pw_checkname(arg1, 0);
        }

        while ((ch = getopt(argc, argv, args)) != -1) {
                switch (ch) {
                case 'C':
                        cfg = optarg;
                        break;
                case 'q':
                        quiet = true;
                        break;
                case 'n':
                        name = pw_checkname(optarg, 0);
                        break;
                case 'u':
                        userid = optarg;
                        break;
                case 'c':
                        gecos = pw_checkname(optarg, 1);
                        break;
                case 'd':
                        homedir = optarg;
                        break;
                case 'e':
                        if (genconf)
                            cmdcnf->expire_days = validate_expire(optarg, ch);
                        else
                            cmdcnf->expire_days = parse_date(now, optarg);
                        break;
                case 'p':
                        if (genconf)
                            cmdcnf->password_days = validate_expire(optarg, ch);
                        else
                            cmdcnf->password_days = parse_date(now, optarg);
                        break;
                case 'g':
                        validate_grname(cmdcnf, optarg);
                        grname = optarg;
                        break;
                case 'G':
                        split_groups(&cmdcnf->groups, optarg);
                        break;
                case 'm':
                        createhome = true;
                        break;
                case 'M':
                        cmdcnf->homemode = validate_mode(optarg);
                        break;
                case 'k':
                        walk = skel = optarg;
                        if (*walk == '/')
                                walk++;
                        if (fstatat(conf.rootfd, walk, &st, 0) == -1)
                                errx(EX_OSFILE, "skeleton `%s' does not "
                                    "exists", skel);
                        if (!S_ISDIR(st.st_mode))
                                errx(EX_OSFILE, "skeleton `%s' is not a "
                                    "directory", skel);
                        cmdcnf->dotdir = skel;
                        break;
                case 's':
                        cmdcnf->shell_default = optarg;
                        break;
                case 'o':
                        conf.checkduplicate = false;
                        break;
                case 'L':
                        cmdcnf->default_class = pw_checkname(optarg, 0);
                        break;
                case 'i':
                        groupid = optarg;
                        break;
                case 'w':
                        default_passwd = optarg;
                        break;
                case 'H':
                        if (fd != -1)
                                errx(EX_USAGE, "'-h' and '-H' are mutually "
                                    "exclusive options");
                        fd = pw_checkfd(optarg);
                        precrypted = true;
                        if (fd == '-')
                                errx(EX_USAGE, "-H expects a file descriptor");
                        break;
                case 'h':
                        if (fd != -1)
                                errx(EX_USAGE, "'-h' and '-H' are mutually "
                                    "exclusive options");
                        fd = pw_checkfd(optarg);
                        break;
                case 'D':
                        genconf = true;
                        break;
                case 'b':
                        cmdcnf->home = optarg;
                        break;
                case 'N':
                        dryrun = true;
                        break;
                case 'P':
                        pretty = true;
                        break;
                case 'y':
                        cmdcnf->nispasswd = optarg;
                        break;
                case 'Y':
                        nis = true;
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if (argc > 0)
                usage();

        if (!dryrun)
                pw_check_root();

        if (quiet)
                freopen(_PATH_DEVNULL, "w", stderr);

        cnf = get_userconfig(cfg);

        mix_config(cmdcnf, cnf);
        if (default_passwd)
                cmdcnf->default_password = passwd_val(default_passwd,
                    cnf->default_password);
        if (genconf) {
                if (name != NULL)
                        errx(EX_DATAERR, "can't combine `-D' with `-n name'");
                if (userid != NULL) {
                        if ((p = strtok(userid, ", \t")) != NULL)
                                cmdcnf->min_uid = pw_checkid(p, UID_MAX);
                        if (cmdcnf->min_uid == 0)
                                cmdcnf->min_uid = 1000;
                        if ((p = strtok(NULL, " ,\t")) != NULL)
                                cmdcnf->max_uid = pw_checkid(p, UID_MAX);
                        if (cmdcnf->max_uid == 0)
                                cmdcnf->max_uid = 32000;
                }
                if (groupid != NULL) {
                        if ((p = strtok(groupid, ", \t")) != NULL)
                                cmdcnf->min_gid = pw_checkid(p, GID_MAX);
                        if (cmdcnf->min_gid == 0)
                                cmdcnf->min_gid = 1000;
                        if ((p = strtok(NULL, " ,\t")) != NULL)
                                cmdcnf->max_gid = pw_checkid(p, GID_MAX);
                        if (cmdcnf->max_gid == 0)
                                cmdcnf->max_gid = 32000;
                }
                if (write_userconfig(cmdcnf, cfg))
                        return (EXIT_SUCCESS);
                err(EX_IOERR, "config update");
        }

        if (userid)
                id = pw_checkid(userid, UID_MAX);
        if (id < 0 && name == NULL)
                errx(EX_DATAERR, "user name or id required");

        if (name == NULL)
                errx(EX_DATAERR, "login name required");

        if (GETPWNAM(name) != NULL)
                errx(EX_DATAERR, "login name `%s' already exists", name);

        if (!grname)
                grname = cmdcnf->default_group;

        pwd = &fakeuser;
        pwd->pw_name = name;
        pwd->pw_class = cmdcnf->default_class ? cmdcnf->default_class : "";
        pwd->pw_uid = pw_uidpolicy(cmdcnf, id);
        pwd->pw_gid = pw_gidpolicy(cnf, grname, pwd->pw_name,
            (gid_t) pwd->pw_uid, dryrun);

        /* cmdcnf->password_days and cmdcnf->expire_days hold unixtime here */
        if (cmdcnf->password_days > 0)
                pwd->pw_change = cmdcnf->password_days;
        if (cmdcnf->expire_days > 0)
                pwd->pw_expire = cmdcnf->expire_days;

        pwd->pw_dir = pw_homepolicy(cmdcnf, homedir, pwd->pw_name);
        pwd->pw_shell = pw_shellpolicy(cmdcnf);
        lc = login_getpwclass(pwd);
        if (lc == NULL || login_setcryptfmt(lc, "sha512", NULL) == NULL)
                warn("setting crypt(3) format");
        login_close(lc);
        pwd->pw_passwd = pw_password(cmdcnf, pwd->pw_name);
        if (pwd->pw_uid == 0 && strcmp(pwd->pw_name, "root") != 0)
                warnx("WARNING: new account `%s' has a uid of 0 "
                    "(superuser access!)", pwd->pw_name);
        if (gecos)
                pwd->pw_gecos = gecos;

        if (fd != -1)
                pw_set_passwd(pwd, fd, precrypted, false);

        if (dryrun)
                return (print_user(pwd, pretty, false));

        if ((rc = addpwent(pwd)) != 0) {
                if (rc == -1)
                        errx(EX_IOERR, "user '%s' already exists",
                            pwd->pw_name);
                else if (rc != 0)
                        err(EX_IOERR, "passwd file update");
        }
        if (nis && cmdcnf->nispasswd && *cmdcnf->nispasswd == '/') {
                printf("%s\n", cmdcnf->nispasswd);
                rc = addnispwent(cmdcnf->nispasswd, pwd);
                if (rc == -1)
                        warnx("User '%s' already exists in NIS passwd",
                            pwd->pw_name);
                else if (rc != 0)
                        warn("NIS passwd update");
                /* NOTE: we treat NIS-only update errors as non-fatal */
        }

        if (cmdcnf->groups != NULL) {
                for (i = 0; i < cmdcnf->groups->sl_cur; i++) {
                        grp = GETGRNAM(cmdcnf->groups->sl_str[i]);
                        /* gr_add doesn't check if new member is already in group */
                        if (grp_has_member(grp, pwd->pw_name))
                                continue;
                        grp = gr_add(grp, pwd->pw_name);
                        /*
                         * grp can only be NULL in 2 cases:
                         * - the new member is already a member
                         * - a problem with memory occurs
                         * in both cases we want to skip now.
                         */
                        if (grp == NULL)
                                continue;
                        chggrent(grp->gr_name, grp);
                        free(grp);
                }
        }

        pwd = GETPWNAM(name);
        if (pwd == NULL)
                errx(EX_NOUSER, "user '%s' disappeared during update", name);

        grp = GETGRGID(pwd->pw_gid);
        pw_log(cnf, M_ADD, W_USER, "%s(%ju):%s(%ju):%s:%s:%s",
               pwd->pw_name, (uintmax_t)pwd->pw_uid,
            grp ? grp->gr_name : "unknown",
               (uintmax_t)(grp ? grp->gr_gid : (uid_t)-1),
               pwd->pw_gecos, pwd->pw_dir, pwd->pw_shell);

        /*
         * let's touch and chown the user's mail file. This is not
         * strictly necessary under BSD with a 0755 maildir but it also
         * doesn't hurt anything to create the empty mailfile
         */
        if (PWALTDIR() != PWF_ALT) {
                snprintf(path, sizeof(path), "%s/%s", _PATH_MAILDIR,
                    pwd->pw_name);
                /* Preserve contents & mtime */
                close(openat(conf.rootfd, path +1, O_RDWR | O_CREAT, 0600));
                fchownat(conf.rootfd, path + 1, pwd->pw_uid, pwd->pw_gid,
                    AT_SYMLINK_NOFOLLOW);
        }

        /*
         * Let's create and populate the user's home directory. Note
         * that this also `works' for editing users if -m is used, but
         * existing files will *not* be overwritten.
         */
        if (PWALTDIR() != PWF_ALT && createhome && pwd->pw_dir &&
            *pwd->pw_dir == '/' && pwd->pw_dir[1])
                create_and_populate_homedir(cmdcnf, pwd, cmdcnf->dotdir,
                    cmdcnf->homemode, false);

        if (!PWALTDIR() && cmdcnf->newmail && *cmdcnf->newmail &&
            (fp = fopen(cnf->newmail, "r")) != NULL) {
                if ((pfp = popen(_PATH_SENDMAIL " -t", "w")) == NULL)
                        warn("sendmail");
                else {
                        fprintf(pfp, "From: root\n" "To: %s\n"
                            "Subject: Welcome!\n\n", pwd->pw_name);
                        while (fgets(line, sizeof(line), fp) != NULL) {
                                /* Do substitutions? */
                                fputs(line, pfp);
                        }
                        pclose(pfp);
                        pw_log(cnf, M_ADD, W_USER, "%s(%ju) new user mail sent",
                            pwd->pw_name, (uintmax_t)pwd->pw_uid);
                }
                fclose(fp);
        }

        if (nis && nis_update() == 0)
                pw_log(cnf, M_ADD, W_USER, "NIS maps updated");

        return (EXIT_SUCCESS);
}

int
pw_user_mod(int argc, char **argv, char *arg1)
{
        struct userconf *cnf;
        struct passwd *pwd;
        struct group *grp;
        StringList *groups = NULL;
        char args[] = "C:qn:u:c:d:e:p:g:G:mM:l:k:s:w:L:h:H:NPYy:";
        const char *cfg = NULL;
        char *gecos, *homedir, *grname, *name, *newname, *walk, *skel, *shell;
        char *passwd, *class, *nispasswd;
        login_cap_t *lc;
        struct stat st;
        intmax_t id = -1;
        int ch, fd = -1;
        size_t i, j;
        bool quiet, createhome, pretty, dryrun, nis, edited;
        bool precrypted;
        mode_t homemode = 0;
        time_t expire_time, password_time, now;

        expire_time = password_time = -1;
        gecos = homedir = grname = name = newname = skel = shell =NULL;
        passwd = NULL;
        class = nispasswd = NULL;
        quiet = createhome = pretty = dryrun = nis = precrypted = false;
        edited = false;
        now = time(NULL);

        if (arg1 != NULL) {
                if (arg1[strspn(arg1, "0123456789")] == '\0')
                        id = pw_checkid(arg1, UID_MAX);
                else
                        name = arg1;
        }

        while ((ch = getopt(argc, argv, args)) != -1) {
                switch (ch) {
                case 'C':
                        cfg = optarg;
                        break;
                case 'q':
                        quiet = true;
                        break;
                case 'n':
                        name = optarg;
                        break;
                case 'u':
                        id = pw_checkid(optarg, UID_MAX);
                        break;
                case 'c':
                        gecos = pw_checkname(optarg, 1);
                        break;
                case 'd':
                        homedir = optarg;
                        break;
                case 'e':
                        expire_time = parse_date(now, optarg);
                        break;
                case 'p':
                        password_time = parse_date(now, optarg);
                        break;
                case 'g':
                        group_from_name_or_id(optarg);
                        grname = optarg;
                        break;
                case 'G':
                        split_groups(&groups, optarg);
                        break;
                case 'm':
                        createhome = true;
                        break;
                case 'M':
                        homemode = validate_mode(optarg);
                        break;
                case 'l':
                        newname = optarg;
                        break;
                case 'k':
                        walk = skel = optarg;
                        if (*walk == '/')
                                walk++;
                        if (fstatat(conf.rootfd, walk, &st, 0) == -1)
                                errx(EX_OSFILE, "skeleton `%s' does not "
                                    "exists", skel);
                        if (!S_ISDIR(st.st_mode))
                                errx(EX_OSFILE, "skeleton `%s' is not a "
                                    "directory", skel);
                        break;
                case 's':
                        shell = optarg;
                        break;
                case 'w':
                        passwd = optarg;
                        break;
                case 'L':
                        class = pw_checkname(optarg, 0);
                        break;
                case 'H':
                        if (fd != -1)
                                errx(EX_USAGE, "'-h' and '-H' are mutually "
                                    "exclusive options");
                        fd = pw_checkfd(optarg);
                        precrypted = true;
                        if (fd == '-')
                                errx(EX_USAGE, "-H expects a file descriptor");
                        break;
                case 'h':
                        if (fd != -1)
                                errx(EX_USAGE, "'-h' and '-H' are mutually "
                                    "exclusive options");
                        fd = pw_checkfd(optarg);
                        break;
                case 'N':
                        dryrun = true;
                        break;
                case 'P':
                        pretty = true;
                        break;
                case 'y':
                        nispasswd = optarg;
                        break;
                case 'Y':
                        nis = true;
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if (argc > 0)
                usage();

        if (!dryrun)
                pw_check_root();

        if (quiet)
                freopen(_PATH_DEVNULL, "w", stderr);

        cnf = get_userconfig(cfg);

        if (id < 0 && name == NULL)
                errx(EX_DATAERR, "username or id required");

        pwd = (name != NULL) ? GETPWNAM(pw_checkname(name, 0)) : GETPWUID(id);
        if (pwd == NULL) {
                if (name == NULL)
                        errx(EX_NOUSER, "no such uid `%ju'",
                            (uintmax_t) id);
                errx(EX_NOUSER, "no such user `%s'", name);
        }

        if (name == NULL)
                name = pwd->pw_name;

        if (nis && nispasswd == NULL)
                nispasswd = cnf->nispasswd;

        if (PWF._altdir == PWF_REGULAR &&
            ((pwd->pw_fields & _PWF_SOURCE) != _PWF_FILES)) {
                if ((pwd->pw_fields & _PWF_SOURCE) == _PWF_NIS) {
                        if (!nis && nispasswd && *nispasswd != '/')
                                errx(EX_NOUSER, "Cannot modify NIS user `%s'",
                                    name);
                } else {
                        errx(EX_NOUSER, "Cannot modify non local user `%s'",
                            name);
                }
        }

        if (newname) {
                if (strcmp(pwd->pw_name, "root") == 0)
                        errx(EX_DATAERR, "can't rename `root' account");
                if (strcmp(pwd->pw_name, newname) != 0) {
                        pwd->pw_name = pw_checkname(newname, 0);
                        edited = true;
                }
        }

        if (id >= 0 && pwd->pw_uid != id) {
                pwd->pw_uid = id;
                edited = true;
                if (pwd->pw_uid != 0 && strcmp(pwd->pw_name, "root") == 0)
                        errx(EX_DATAERR, "can't change uid of `root' account");
                if (pwd->pw_uid == 0 && strcmp(pwd->pw_name, "root") != 0)
                        warnx("WARNING: account `%s' will have a uid of 0 "
                            "(superuser access!)", pwd->pw_name);
        }

        if (grname && pwd->pw_uid != 0) {
                grp = GETGRNAM(grname);
                if (grp == NULL)
                        grp = GETGRGID(pw_checkid(grname, GID_MAX));
                if (grp->gr_gid != pwd->pw_gid) {
                        pwd->pw_gid = grp->gr_gid;
                        edited = true;
                }
        }


        if (password_time >= 0 && pwd->pw_change != password_time) {
                pwd->pw_change = password_time;
                edited = true;
        }

        if (expire_time >= 0 && pwd->pw_expire != expire_time) {
                pwd->pw_expire = expire_time;
                edited = true;
        }

        if (shell) {
                shell = shell_path(cnf->shelldir, cnf->shells, shell);
                if (shell == NULL)
                        shell = "";
                if (strcmp(shell, pwd->pw_shell) != 0) {
                        pwd->pw_shell = shell;
                        edited = true;
                }
        }

        if (class && strcmp(pwd->pw_class, class) != 0) {
                pwd->pw_class = class;
                edited = true;
        }

        if (homedir && strcmp(pwd->pw_dir, homedir) != 0) {
                pwd->pw_dir = homedir;
                edited = true;
                if (fstatat(conf.rootfd, pwd->pw_dir, &st, 0) == -1) {
                        if (!createhome)
                                warnx("WARNING: home `%s' does not exist",
                                    pwd->pw_dir);
                } else if (!S_ISDIR(st.st_mode)) {
                        warnx("WARNING: home `%s' is not a directory",
                            pwd->pw_dir);
                }
        }

        if (passwd && conf.fd == -1) {
                lc = login_getpwclass(pwd);
                if (lc == NULL || login_setcryptfmt(lc, "sha512", NULL) == NULL)
                        warn("setting crypt(3) format");
                login_close(lc);
                cnf->default_password = passwd_val(passwd,
                    cnf->default_password);
                pwd->pw_passwd = pw_password(cnf, pwd->pw_name);
                edited = true;
        }

        if (gecos && strcmp(pwd->pw_gecos, gecos) != 0) {
                pwd->pw_gecos = gecos;
                edited = true;
        }

        if (fd != -1)
                edited = pw_set_passwd(pwd, fd, precrypted, true);

        if (dryrun)
                return (print_user(pwd, pretty, false));

        if (edited) /* Only updated this if required */
                perform_chgpwent(name, pwd, nis ? nispasswd : NULL);
        /* Now perform the needed changes concern groups */
        if (groups != NULL) {
                /* Delete User from groups using old name */
                SETGRENT();
                while ((grp = GETGRENT()) != NULL) {
                        if (grp->gr_mem == NULL)
                                continue;
                        for (i = 0; grp->gr_mem[i] != NULL; i++) {
                                if (strcmp(grp->gr_mem[i] , name) != 0)
                                        continue;
                                for (j = i; grp->gr_mem[j] != NULL ; j++)
                                        grp->gr_mem[j] = grp->gr_mem[j+1];
                                chggrent(grp->gr_name, grp);
                                break;
                        }
                }
                ENDGRENT();
                /* Add the user to the needed groups */
                for (i = 0; i < groups->sl_cur; i++) {
                        grp = GETGRNAM(groups->sl_str[i]);
                        grp = gr_add(grp, pwd->pw_name);
                        if (grp == NULL)
                                continue;
                        chggrent(grp->gr_name, grp);
                        free(grp);
                }
        }
        /* In case of rename we need to walk over the different groups */
        if (newname) {
                SETGRENT();
                while ((grp = GETGRENT()) != NULL) {
                        if (grp->gr_mem == NULL)
                                continue;
                        for (i = 0; grp->gr_mem[i] != NULL; i++) {
                                if (strcmp(grp->gr_mem[i], name) != 0)
                                        continue;
                                grp->gr_mem[i] = newname;
                                chggrent(grp->gr_name, grp);
                                break;
                        }
                }
        }

        /* go get a current version of pwd */
        if (newname)
                name = newname;
        pwd = GETPWNAM(name);
        if (pwd == NULL)
                errx(EX_NOUSER, "user '%s' disappeared during update", name);
        grp = GETGRGID(pwd->pw_gid);
        pw_log(cnf, M_MODIFY, W_USER, "%s(%ju):%s(%ju):%s:%s:%s",
            pwd->pw_name, (uintmax_t)pwd->pw_uid,
            grp ? grp->gr_name : "unknown",
            (uintmax_t)(grp ? grp->gr_gid : (uid_t)-1),
            pwd->pw_gecos, pwd->pw_dir, pwd->pw_shell);

        /*
         * Let's create and populate the user's home directory. Note
         * that this also `works' for editing users if -m is used, but
         * existing files will *not* be overwritten.
         */
        if (PWALTDIR() != PWF_ALT && createhome && pwd->pw_dir &&
            *pwd->pw_dir == '/' && pwd->pw_dir[1]) {
                if (!skel)
                        skel = cnf->dotdir;
                if (homemode == 0)
                        homemode = cnf->homemode;
                create_and_populate_homedir(cnf, pwd, skel, homemode, true);
        }

        if (nis && nis_update() == 0)
                pw_log(cnf, M_MODIFY, W_USER, "NIS maps updated");

        return (EXIT_SUCCESS);
}