/*-
 * SPDX-License-Identifier: BSD-4-Clause
 *
 * Copyright (c) 1995, 1996
 *      Bill Paul <wpaul@ctr.columbia.edu>.  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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Bill Paul.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY Bill Paul 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 Bill Paul 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/fcntl.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/wait.h>

#include <arpa/inet.h>
#include <netinet/in.h>

#include <ctype.h>
#include <db.h>
#include <dirent.h>
#include <errno.h>
#include <limits.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <libgen.h>
#include <libutil.h>

#include <rpc/rpc.h>
#include <rpcsvc/yp.h>
struct dom_binding;
#include <rpcsvc/ypclnt.h>
#include "yppasswdd_extern.h"
#include "yppasswd.h"
#include "yppasswd_private.h"
#include "ypxfr_extern.h"
#include "yp_extern.h"

static struct passwd yp_password;

static void
xlate_passwd(struct x_master_passwd *xpwd, struct passwd *pwd)
{
        pwd->pw_name = xpwd->pw_name;
        pwd->pw_passwd = xpwd->pw_passwd;
        pwd->pw_uid = xpwd->pw_uid;
        pwd->pw_gid = xpwd->pw_gid;
        pwd->pw_change = xpwd->pw_change;
        pwd->pw_class = xpwd->pw_class;
        pwd->pw_gecos = xpwd->pw_gecos;
        pwd->pw_dir = xpwd->pw_dir;
        pwd->pw_shell = xpwd->pw_shell;
        pwd->pw_expire = xpwd->pw_expire;
        pwd->pw_fields = xpwd->pw_fields;
}

static void
copy_yp_pass(char *p, int x, int m)
{
        char *t, *s = p;
        static char *buf;

        yp_password.pw_fields = 0;

        buf = realloc(buf, m + 10);
        bzero(buf, m + 10);

        /* Turn all colons into NULLs */
        while (strchr(s, ':')) {
                s = (strchr(s, ':') + 1);
                *(s - 1)= '\0';
        }

        t = buf;
#define EXPAND(e) do { \
        e = t; \
        while ((*t++ = *p++)); \
} while (0)
        EXPAND(yp_password.pw_name);
        yp_password.pw_fields |= _PWF_NAME;
        EXPAND(yp_password.pw_passwd);
        yp_password.pw_fields |= _PWF_PASSWD;
        yp_password.pw_uid = atoi(p);
        p += (strlen(p) + 1);
        yp_password.pw_fields |= _PWF_UID;
        yp_password.pw_gid = atoi(p);
        p += (strlen(p) + 1);
        yp_password.pw_fields |= _PWF_GID;
        if (x) {
                EXPAND(yp_password.pw_class);
                yp_password.pw_fields |= _PWF_CLASS;
                yp_password.pw_change = atol(p);
                p += (strlen(p) + 1);
                yp_password.pw_fields |= _PWF_CHANGE;
                yp_password.pw_expire = atol(p);
                p += (strlen(p) + 1);
                yp_password.pw_fields |= _PWF_EXPIRE;
        }
        EXPAND(yp_password.pw_gecos);
        yp_password.pw_fields |= _PWF_GECOS;
        EXPAND(yp_password.pw_dir);
        yp_password.pw_fields |= _PWF_DIR;
        EXPAND(yp_password.pw_shell);
        yp_password.pw_fields |= _PWF_SHELL;
}

static int
validchars(char *arg)
{
        size_t i;

        for (i = 0; i < strlen(arg); i++) {
                if (iscntrl(arg[i])) {
                        yp_error("string contains a control character");
                        return(1);
                }
                if (arg[i] == ':') {
                        yp_error("string contains a colon");
                        return(1);
                }
                /* Be evil: truncate strings with \n in them silently. */
                if (arg[i] == '\n') {
                        arg[i] = '\0';
                        return(0);
                }
        }
        return(0);
}

static int
validate_master(struct passwd *opw __unused, struct x_master_passwd *npw)
{

        if (npw->pw_name[0] == '+' || npw->pw_name[0] == '-') {
                yp_error("client tried to modify an NIS entry");
                return(1);
        }

        if (validchars(npw->pw_shell)) {
                yp_error("specified shell contains invalid characters");
                return(1);
        }

        if (validchars(npw->pw_gecos)) {
                yp_error("specified gecos field contains invalid characters");
                return(1);
        }

        if (validchars(npw->pw_passwd)) {
                yp_error("specified password contains invalid characters");
                return(1);
        }
        return(0);
}

static int
validate(struct passwd *opw, struct x_passwd *npw)
{

        if (npw->pw_name[0] == '+' || npw->pw_name[0] == '-') {
                yp_error("client tried to modify an NIS entry");
                return(1);
        }

        if ((uid_t)npw->pw_uid != opw->pw_uid) {
                yp_error("UID mismatch: client says user %s has UID %d",
                         npw->pw_name, npw->pw_uid);
                yp_error("database says user %s has UID %d", opw->pw_name,
                         opw->pw_uid);
                return(1);
        }

        if ((gid_t)npw->pw_gid != opw->pw_gid) {
                yp_error("GID mismatch: client says user %s has GID %d",
                         npw->pw_name, npw->pw_gid);
                yp_error("database says user %s has GID %d", opw->pw_name,
                         opw->pw_gid);
                return(1);
        }

        /*
         * Don't allow the user to shoot himself in the foot,
         * even on purpose.
         */
        if (!no_chsh && !ok_shell(npw->pw_shell)) {
                yp_error("%s is not a valid shell", npw->pw_shell);
                return(1);
        }

        if (!no_chsh && validchars(npw->pw_shell)) {
                yp_error("specified shell contains invalid characters");
                return(1);
        }

        if (validchars(npw->pw_gecos)) {
                yp_error("specified gecos field contains invalid characters");
                return(1);
        }

        if (validchars(npw->pw_passwd)) {
                yp_error("specified password contains invalid characters");
                return(1);
        }
        return(0);
}

/*
 * Kludge alert:
 * In order to have one rpc.yppasswdd support multiple domains,
 * we have to cheat: we search each directory under /var/yp
 * and try to match the user in each master.passwd.byname
 * map that we find. If the user matches (username, uid and gid
 * all agree), then we use that domain. If we match the user in
 * more than one database, we must abort.
 */
static char *
find_domain(struct x_passwd *pw)
{
        struct stat statbuf;
        struct dirent *dirp;
        DIR *dird;
        char yp_mapdir[MAXPATHLEN + 2];
        static char domain[YPMAXDOMAIN];
        char *tmp = NULL;
        DBT key, data;
        int hit = 0;

        yp_error("performing multidomain lookup");

        if ((dird = opendir(yp_dir)) == NULL) {
                yp_error("opendir(%s) failed: %s", yp_dir, strerror(errno));
                return(NULL);
        }

        while ((dirp = readdir(dird)) != NULL) {
                snprintf(yp_mapdir, sizeof yp_mapdir, "%s/%s",
                                                        yp_dir, dirp->d_name);
                if (stat(yp_mapdir, &statbuf) < 0) {
                        yp_error("stat(%s) failed: %s", yp_mapdir,
                                                        strerror(errno));
                        closedir(dird);
                        return(NULL);
                }
                if (S_ISDIR(statbuf.st_mode)) {
                        tmp = (char *)dirp->d_name;
                        key.data = pw->pw_name;
                        key.size = strlen(pw->pw_name);

                        if (yp_get_record(tmp,"master.passwd.byname",
                                        &key, &data, 0) != YP_TRUE) {
                                continue;
                        }
                        *((char *)data.data + data.size) = '\0';
                        copy_yp_pass(data.data, 1, data.size);
                        if (yp_password.pw_uid == (uid_t)pw->pw_uid &&
                            yp_password.pw_gid == (gid_t)pw->pw_gid) {
                                hit++;
                                snprintf(domain, YPMAXDOMAIN, "%s", tmp);
                        }
                }
        }

        closedir(dird);
        if (hit > 1) {
                yp_error("found same user in two different domains");
                return(NULL);
        } else
                return((char *)&domain);
}

static const char *maps[] = {
        "master.passwd.byname",
        "master.passwd.byuid",
        "passwd.byname",
        "passwd.byuid"
};

static const char *formats[] = {
        "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s",
        "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s",
        "%s:%s:%d:%d:%s:%s:%s",
        "%s:%s:%d:%d:%s:%s:%s"
};

static int
update_inplace(struct passwd *pw, char *domain)
{
        DB *dbp = NULL;
        DBT key = { NULL, 0 };
        DBT data = { NULL, 0 };
        char *pwbuf;
        char keybuf[20];
        int i;
        char *ptr = NULL;
        static char yp_last[] = "YP_LAST_MODIFIED";
        char yplastbuf[64];

        snprintf(yplastbuf, sizeof yplastbuf, "%llu",
            (unsigned long long)time(NULL));
        pwbuf = NULL;

        for (i = 0; i < 4; i++) {

                if (i % 2) {
                        snprintf(keybuf, sizeof keybuf,
                            "%llu", (unsigned long long)pw->pw_uid);
                        key.data = &keybuf;
                        key.size = strlen(keybuf);
                } else {
                        key.data = pw->pw_name;
                        key.size = strlen(pw->pw_name);
                }

                /*
                 * XXX The passwd.byname and passwd.byuid maps come in
                 * two flavors: secure and insecure. The secure version
                 * has a '*' in the password field whereas the insecure one
                 * has a real crypted password. The maps will be insecure
                 * if they were built with 'unsecure = TRUE' enabled in
                 * /var/yp/Makefile, but we'd have no way of knowing if
                 * this has been done unless we were to try parsing the
                 * Makefile, which is a disgusting thought. Instead, we
                 * read the records from the maps, skip to the first ':'
                 * in them, and then look at the character immediately
                 * following it. If it's an '*' then the map is 'secure'
                 * and we must not insert a real password into the pw_passwd
                 * field. If it's not an '*', then we put the real crypted
                 * password in.
                 */
                if (yp_get_record(domain,maps[i],&key,&data,1) != YP_TRUE) {
                        yp_error("couldn't read %s/%s: %s", domain,
                                                maps[i], strerror(errno));
                        goto ret1;
                }

                if ((ptr = strchr(data.data, ':')) == NULL) {
                        yp_error("no colon in passwd record?!");
                        goto ret1;
                }

                /*
                 * XXX Supposing we have more than one user with the same
                 * UID? (Or more than one user with the same name?) We could
                 * end up modifying the wrong record if were not careful.
                 */
                if (i % 2) {
                        if (strncmp(data.data, pw->pw_name,
                                                        strlen(pw->pw_name))) {
                                yp_error("warning: found entry for UID %d \
in map %s@%s with wrong name (%.*s)", pw->pw_uid, maps[i], domain,
                                    (int)(ptr - (char *)data.data),
                                    (char *)data.data);
                                yp_error("there may be more than one user \
with the same UID - continuing");
                                continue;
                        }
                } else {
                        /*
                         * We're really being ultra-paranoid here.
                         * This is generally a 'can't happen' condition.
                         */
                        free(pwbuf);
                        asprintf(&pwbuf, ":%d:%d:", pw->pw_uid, pw->pw_gid);
                        if (pwbuf == NULL) {
                                yp_error("no memory");
                                goto ret1;
                        }
                        if (!strstr(data.data, pwbuf)) {
                                yp_error("warning: found entry for user %s \
in map %s@%s with wrong UID", pw->pw_name, maps[i], domain);
                                yp_error("there may be more than one user \
with the same name - continuing");
                                continue;
                        }
                }

                if (i < 2) {
                        free(pwbuf);
                        asprintf(&pwbuf, formats[i],
                           pw->pw_name, pw->pw_passwd, pw->pw_uid,
                           pw->pw_gid, pw->pw_class, pw->pw_change,
                           pw->pw_expire, pw->pw_gecos, pw->pw_dir,
                           pw->pw_shell);
                } else {
                        free(pwbuf);
                        asprintf(&pwbuf, formats[i],
                           pw->pw_name, *(ptr+1) == '*' ? "*" : pw->pw_passwd,
                           pw->pw_uid, pw->pw_gid, pw->pw_gecos, pw->pw_dir,
                           pw->pw_shell);
                }
                if (pwbuf == NULL) {
                        yp_error("no memory");
                        goto ret1;
                }

#define FLAGS O_RDWR|O_CREAT

                if ((dbp = yp_open_db_rw(domain, maps[i], FLAGS)) == NULL) {
                        yp_error("couldn't open %s/%s r/w: %s",domain,
                                                maps[i],strerror(errno));
                        goto ret1;
                }

                data.data = pwbuf;
                data.size = strlen(pwbuf);

                if (yp_put_record(dbp, &key, &data, 1) != YP_TRUE) {
                        yp_error("failed to update record in %s/%s", domain,
                                                                maps[i]);
                        (void)(dbp->close)(dbp);
                        goto ret1;
                }

                key.data = yp_last;
                key.size = strlen(yp_last);
                data.data = (char *)&yplastbuf;
                data.size = strlen(yplastbuf);

                if (yp_put_record(dbp, &key, &data, 1) != YP_TRUE) {
                        yp_error("failed to update timestamp in %s/%s", domain,
                                                                maps[i]);
                        (void)(dbp->close)(dbp);
                        goto ret1;
                }

                (void)(dbp->close)(dbp);
        }

        free(pwbuf);
        return (0);
ret1:
        free(pwbuf);
        return (1);
}

int *
yppasswdproc_update_1_svc(yppasswd *argp, struct svc_req *rqstp)
{
        static int  result;
        struct sockaddr_in *rqhost;
        DBT key, data;
        int rval = 0;
        int pfd, tfd;
        int pid;
        int passwd_changed = 0;
        int shell_changed = 0;
        int gecos_changed = 0;
        char *cryptpw;
        char *oldshell = NULL;
        char *oldgecos = NULL;
        char *passdir;
        char *passfile_hold;
        char passdir_buf[MAXPATHLEN + 2];
        char passfile_buf[MAXPATHLEN + 2];
        char passfile_hold_buf[MAXPATHLEN + 2];
        char *domain = yppasswd_domain;
        static struct sockaddr_in clntaddr;
        static struct timeval t_saved, t_test;

        /*
         * Normal user updates always use the 'default' master.passwd file.
         */

        passfile = passfile_default;
        result = 1;

        rqhost = svc_getcaller(rqstp->rq_xprt);

        gettimeofday(&t_test, NULL);
        if (!bcmp(rqhost, &clntaddr, sizeof *rqhost) &&
                t_test.tv_sec > t_saved.tv_sec &&
                t_test.tv_sec - t_saved.tv_sec < 300) {

                bzero(&clntaddr, sizeof clntaddr);
                bzero(&t_saved, sizeof t_saved);
                return(NULL);
        }

        bcopy(rqhost, &clntaddr, sizeof clntaddr);
        gettimeofday(&t_saved, NULL);

        if (yp_access(resvport ? "master.passwd.byname" : NULL, rqstp)) {
                yp_error("rejected update request from unauthorized host");
                svcerr_auth(rqstp->rq_xprt, AUTH_BADCRED);
                return(&result);
        }

        /*
         * Step one: find the user. (It's kinda pointless to
         * proceed if the user doesn't exist.) We look for the
         * user in the master.passwd.byname database, _NOT_ by
         * using getpwent() and friends! We can't use getpwent()
         * since the NIS master server is not guaranteed to be
         * configured as an NIS client.
         */

        if (multidomain) {
                if ((domain = find_domain(&argp->newpw)) == NULL) {
                        yp_error("multidomain lookup failed - aborting update");
                        return(&result);
                } else
                        yp_error("updating user %s in domain %s",
                                        argp->newpw.pw_name, domain);
        }

        key.data = argp->newpw.pw_name;
        key.size = strlen(argp->newpw.pw_name);

        if ((rval = yp_get_record(domain,"master.passwd.byname",
                        &key, &data, 0)) != YP_TRUE) {
                if (rval == YP_NOKEY) {
                        yp_error("user %s not found in passwd database",
                                argp->newpw.pw_name);
                } else {
                        yp_error("database access error: %s",
                                yperr_string(rval));
                }
                return(&result);
        }

        /* Nul terminate, please. */
        *((char *)data.data + data.size) = '\0';

        copy_yp_pass(data.data, 1, data.size);

        /* Step 2: check that the supplied oldpass is valid. */

        cryptpw = crypt(argp->oldpass, yp_password.pw_passwd);
        if (cryptpw == NULL || strcmp(cryptpw, yp_password.pw_passwd)) {
                yp_error("rejected change attempt -- bad password");
                yp_error("client address: %s username: %s",
                          inet_ntoa(rqhost->sin_addr),
                          argp->newpw.pw_name);
                return(&result);
        }

        /* Step 3: validate the arguments passed to us by the client. */

        if (validate(&yp_password, &argp->newpw)) {
                yp_error("rejecting change attempt: bad arguments");
                yp_error("client address: %s username: %s",
                         inet_ntoa(rqhost->sin_addr),
                         argp->newpw.pw_name);
                svcerr_decode(rqstp->rq_xprt);
                return(&result);
        }

        /* Step 4: update the user's passwd structure. */

        if (!no_chsh && strcmp(argp->newpw.pw_shell, yp_password.pw_shell)) {
                oldshell = yp_password.pw_shell;
                yp_password.pw_shell = argp->newpw.pw_shell;
                shell_changed++;
        }


        if (!no_chfn && strcmp(argp->newpw.pw_gecos, yp_password.pw_gecos)) {
                oldgecos = yp_password.pw_gecos;
                yp_password.pw_gecos = argp->newpw.pw_gecos;
                gecos_changed++;
        }

        if (strcmp(argp->newpw.pw_passwd, yp_password.pw_passwd)) {
                yp_password.pw_passwd = argp->newpw.pw_passwd;
                yp_password.pw_change = 0;
                passwd_changed++;
        }

        /*
         * If the caller specified a domain other than our 'default'
         * domain, change the path to master.passwd accordingly.
         */

        if (strcmp(domain, yppasswd_domain)) {
                snprintf(passfile_buf, sizeof(passfile_buf),
                        "%s/%s/master.passwd", yp_dir, domain);
                passfile = (char *)&passfile_buf;
        }

        /*
         * Create a filename to hold the original master.passwd
         * so if our call to yppwupdate fails we can roll back
         */
        snprintf(passfile_hold_buf, sizeof(passfile_hold_buf),
            "%s.hold", passfile);
        passfile_hold = (char *)&passfile_hold_buf;


        /* Step 5: make a new password file with the updated info. */

        snprintf(passdir_buf, sizeof(passdir_buf), "%s", passfile);
        passdir = dirname(passdir_buf);

        if (pw_init(passdir, passfile)) {
                yp_error("pw_init() failed");
                return &result;
        }
        if ((pfd = pw_lock()) == -1) {
                pw_fini();
                yp_error("pw_lock() failed");
                return &result;
        }
        if ((tfd = pw_tmp(-1)) == -1) {
                pw_fini();
                yp_error("pw_tmp() failed");
                return &result;
        }
        if (pw_copy(pfd, tfd, &yp_password, NULL) == -1) {
                pw_fini();
                yp_error("pw_copy() failed");
                return &result;
        }
        if (rename(passfile, passfile_hold) == -1) {
                pw_fini();
                yp_error("rename of %s to %s failed", passfile,
                    passfile_hold);
                return &result;
        }

        if (strcmp(passfile, _PATH_MASTERPASSWD) == 0) { 
                /*
                 * NIS server is exporting the system's master.passwd.
                 * Call pw_mkdb to rebuild passwd and the .db files
                 */
                if (pw_mkdb(yp_password.pw_name) == -1) {
                        pw_fini();
                        yp_error("pw_mkdb() failed");
                        rename(passfile_hold, passfile);
                        return &result;
                }
        } else {
                /*
                 * NIS server is exporting a private master.passwd.
                 * Rename tempfile into final location
                 */
                if (rename(pw_tempname(), passfile) == -1) {
                        pw_fini();
                        yp_error("rename of %s to %s failed",
                            pw_tempname(), passfile);
                        rename(passfile_hold, passfile);
                        return &result;
                }
        }

        pw_fini();

        if (inplace) {
                if ((rval = update_inplace(&yp_password, domain))) {
                        yp_error("inplace update failed -- rebuilding maps");
                }
        }

        switch ((pid = fork())) {
        case 0:
                if (inplace && !rval) {
                        execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
                                yppasswd_domain, "pushpw", (char *)NULL);
                } else {
                        execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
                                yppasswd_domain, (char *)NULL);
                }
                yp_error("couldn't exec map update process: %s",
                                        strerror(errno));
                unlink(passfile);
                rename(passfile_hold, passfile);
                exit(1);
                break;
        case -1:
                yp_error("fork() failed: %s", strerror(errno));
                unlink(passfile);
                rename(passfile_hold, passfile);
                return(&result);
                break;
        default:
                unlink(passfile_hold);
                break;
        }

        if (verbose) {
                yp_error("update completed for user %s (uid %d) in %s:",
                    argp->newpw.pw_name, argp->newpw.pw_uid, passfile);

                if (passwd_changed)
                        yp_error("password changed");

                if (gecos_changed)
                        yp_error("gecos changed ('%s' -> '%s')",
                                        oldgecos, argp->newpw.pw_gecos);

                if (shell_changed)
                        yp_error("shell changed ('%s' -> '%s')",
                                        oldshell, argp->newpw.pw_shell);
        }

        result = 0;
        return (&result);
}

/*
 * Note that this function performs a little less sanity checking
 * than the last one. Since only the superuser is allowed to use it,
 * it is assumed that the caller knows what he's doing.
 */
int *
yppasswdproc_update_master_1_svc(master_yppasswd *argp,
    struct svc_req *rqstp)
{
        static int result;
        int pfd, tfd;
        int pid;
        uid_t uid;
        int rval = 0;
        DBT key, data;
        char *passdir;
        char *passfile_hold;
        char passdir_buf[MAXPATHLEN + 2];
        char passfile_buf[MAXPATHLEN + 2];
        char passfile_hold_buf[MAXPATHLEN + 2];
        struct sockaddr_in *rqhost;
        SVCXPRT *transp;
        struct passwd newpasswd;

        result = 1;
        transp = rqstp->rq_xprt;

        /*
         * NO AF_INET CONNETCIONS ALLOWED!
         */
        rqhost = svc_getcaller(transp);
        if (rqhost->sin_family != AF_UNIX) {
                yp_error("Alert! %s/%d attempted to use superuser-only \
procedure!\n", inet_ntoa(rqhost->sin_addr), rqhost->sin_port);
                svcerr_auth(transp, AUTH_BADCRED);
                return(&result);
        }

        if (rqstp->rq_cred.oa_flavor != AUTH_SYS) {
                yp_error("caller didn't send proper credentials");
                svcerr_auth(transp, AUTH_BADCRED);
                return(&result);
        }

        if (__rpc_get_local_uid(transp, &uid) < 0) {
                yp_error("caller didn't send proper credentials");
                svcerr_auth(transp, AUTH_BADCRED);
                return(&result);
        }

        if (uid) {
                yp_error("caller euid is %d, expecting 0 -- rejecting request",
                    uid);
                svcerr_auth(rqstp->rq_xprt, AUTH_BADCRED);
                return(&result);
        }

        passfile = passfile_default;

        key.data = argp->newpw.pw_name;
        key.size = strlen(argp->newpw.pw_name);

        /*
         * The superuser may add entries to the passwd maps if
         * rpc.yppasswdd is started with the -a flag. Paranoia
         * prevents me from allowing additions by default.
         */
        if ((rval = yp_get_record(argp->domain, "master.passwd.byname",
                          &key, &data, 0)) != YP_TRUE) {
                if (rval == YP_NOKEY) {
                        yp_error("user %s not found in passwd database",
                                 argp->newpw.pw_name);
                        if (allow_additions)
                                yp_error("notice: adding user %s to \
master.passwd database for domain %s", argp->newpw.pw_name, argp->domain);
                        else
                                yp_error("restart rpc.yppasswdd with the -a flag to \
allow additions to be made to the password database");
                } else {
                        yp_error("database access error: %s",
                                 yperr_string(rval));
                }
                if (!allow_additions)
                        return(&result);
        } else {

                /* Nul terminate, please. */
                *((char *)data.data + data.size) = '\0';

                copy_yp_pass(data.data, 1, data.size);
        }

        /*
         * Perform a small bit of sanity checking.
         */
        if (validate_master(rval == YP_TRUE ? &yp_password:NULL,&argp->newpw)){
                yp_error("rejecting update attempt for %s: bad arguments",
                         argp->newpw.pw_name);
                return(&result);
        }

        /*
         * If the caller specified a domain other than our 'default'
         * domain, change the path to master.passwd accordingly.
         */

        if (strcmp(argp->domain, yppasswd_domain)) {
                snprintf(passfile_buf, sizeof(passfile_buf),
                        "%s/%s/master.passwd", yp_dir, argp->domain);
                passfile = (char *)&passfile_buf;
        }

        /*
         * Create a filename to hold the original master.passwd
         * so if our call to yppwupdate fails we can roll back
         */
        snprintf(passfile_hold_buf, sizeof(passfile_hold_buf),
            "%s.hold", passfile);
        passfile_hold = (char *)&passfile_hold_buf;

        snprintf(passdir_buf, sizeof(passdir_buf), "%s", passfile);
        passdir = dirname(passdir_buf);

        if (pw_init(passdir, passfile)) {
                yp_error("pw_init() failed");
                return &result;
        }
        if ((pfd = pw_lock()) == -1) {
                pw_fini();
                yp_error("pw_lock() failed");
                return &result;
        }
        if ((tfd = pw_tmp(-1)) == -1) {
                pw_fini();
                yp_error("pw_tmp() failed");
                return &result;
        }
        xlate_passwd(&argp->newpw, &newpasswd);
        if (pw_copy(pfd, tfd, &newpasswd, NULL) == -1) {
                pw_fini();
                yp_error("pw_copy() failed");
                return &result;
        }
        if (rename(passfile, passfile_hold) == -1) {
                pw_fini();
                yp_error("rename of %s to %s failed", passfile,
                    passfile_hold);
                return &result;
        }
        if (strcmp(passfile, _PATH_MASTERPASSWD) == 0) {
                /*
                 * NIS server is exporting the system's master.passwd.
                 * Call pw_mkdb to rebuild passwd and the .db files
                 */
                if (pw_mkdb(argp->newpw.pw_name) == -1) {
                        pw_fini();
                        yp_error("pw_mkdb() failed");
                        rename(passfile_hold, passfile);
                        return &result;
                }
        } else {
                /*
                 * NIS server is exporting a private master.passwd.
                 * Rename tempfile into final location
                 */
                if (rename(pw_tempname(), passfile) == -1) {
                        pw_fini();
                        yp_error("rename of %s to %s failed",
                            pw_tempname(), passfile);
                        rename(passfile_hold, passfile);
                        return &result;
                }
        }
        pw_fini();

        if (inplace) {
                xlate_passwd(&argp->newpw, &newpasswd);
                if ((rval = update_inplace(&newpasswd, argp->domain))) {
                        yp_error("inplace update failed -- rebuilding maps");
                }
        }

        switch ((pid = fork())) {
        case 0:
                if (inplace && !rval) {
                        execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
                                argp->domain, "pushpw", (char *)NULL);
                } else {
                        execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile,
                                argp->domain, (char *)NULL);
                }
                yp_error("couldn't exec map update process: %s",
                                        strerror(errno));
                unlink(passfile);
                rename(passfile_hold, passfile);
                exit(1);
                break;
        case -1:
                yp_error("fork() failed: %s", strerror(errno));
                unlink(passfile);
                rename(passfile_hold, passfile);
                return(&result);
                break;
        default:
                unlink(passfile_hold);
                break;
        }

        yp_error("performed update of user %s (uid %d) domain %s",
                                                argp->newpw.pw_name,
                                                argp->newpw.pw_uid,
                                                argp->domain);

        result = 0;
        return(&result);
}