usr/src/usr.sbin/pwd_mkdb/pwd_mkdb.c

/*-
 * Copyright (c) 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * %sccs.include.redist.c%
 */

#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1991, 1993\n\
        The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)pwd_mkdb.c  8.2 (Berkeley) %G%";
#endif /* not lint */

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

#include <db.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "pw_scan.h"

#define INSECURE        1
#define SECURE          2
#define PERM_INSECURE   (S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)
#define PERM_SECURE     (S_IRUSR|S_IWUSR)

HASHINFO openinfo = {
        4096,           /* bsize */
        32,             /* ffactor */
        256,            /* nelem */
        2048 * 1024,    /* cachesize */
        NULL,           /* hash() */
        0               /* lorder */
};

static enum state { FILE_INSECURE, FILE_SECURE, FILE_ORIG } clean;
static struct passwd pwd;                       /* password structure */
static char *pname;                             /* password file name */

void    cleanup __P((void));
void    error __P((char *));
void    mv __P((char *, char *));
int     scan __P((FILE *, struct passwd *));
void    usage __P((void));

int
main(argc, argv)
        int argc;
        char *argv[];
{
        DB *dp, *edp;
        DBT data, key;
        FILE *fp, *oldfp;
        sigset_t set;
        int ch, cnt, len, makeold, tfd;
        char *p, *t;
        char buf[MAX(MAXPATHLEN, LINE_MAX * 2)], tbuf[1024];

        makeold = 0;
        while ((ch = getopt(argc, argv, "pv")) != EOF)
                switch(ch) {
                case 'p':                       /* create V7 "file.orig" */
                        makeold = 1;
                        break;
                case 'v':                       /* backward compatible */
                        break;
                case '?':
                default:
                        usage();
                }
        argc -= optind;
        argv += optind;

        if (argc != 1)
                usage();

        /*
         * This could be changed to allow the user to interrupt.
         * Probably not worth the effort.
         */
        sigemptyset(&set);
        sigaddset(&set, SIGTSTP);
        sigaddset(&set, SIGHUP);
        sigaddset(&set, SIGINT);
        sigaddset(&set, SIGQUIT);
        sigaddset(&set, SIGTERM);
        (void)sigprocmask(SIG_BLOCK, &set, (sigset_t *)NULL);

        pname = *argv;
        /* Open the original password file */
        if (!(fp = fopen(pname, "r")))
                error(pname);

        /* Open the temporary insecure password database. */
        (void)snprintf(buf, sizeof(buf), "%s.tmp", _PATH_MP_DB);
        dp = dbopen(buf,
            O_RDWR|O_CREAT|O_EXCL, PERM_INSECURE, DB_HASH, &openinfo);
        if (dp == NULL)
                error(buf);
        clean = FILE_INSECURE;

        /*
         * Open file for old password file.  Minor trickiness -- don't want to
         * chance the file already existing, since someone (stupidly) might
         * still be using this for permission checking.  So, open it first and
         * fdopen the resulting fd.  Don't really care who reads it.
         */
        if (makeold) {
                (void)snprintf(buf, sizeof(buf), "%s.orig", pname);
                if ((tfd = open(buf,
                    O_WRONLY|O_CREAT|O_EXCL, PERM_INSECURE)) < 0)
                        error(buf);
                if ((oldfp = fdopen(tfd, "w")) == NULL)
                        error(buf);
                clean = FILE_ORIG;
        }

        /*
         * The databases actually contain three copies of the original data.
         * Each password file entry is converted into a rough approximation
         * of a ``struct passwd'', with the strings placed inline.  This
         * object is then stored as the data for three separate keys.  The
         * first key * is the pw_name field prepended by the _PW_KEYBYNAME
         * character.  The second key is the pw_uid field prepended by the
         * _PW_KEYBYUID character.  The third key is the line number in the
         * original file prepended by the _PW_KEYBYNUM character.  (The special
         * characters are prepended to ensure that the keys do not collide.)
         */
        data.data = (u_char *)buf;
        key.data = (u_char *)tbuf;
        for (cnt = 1; scan(fp, &pwd); ++cnt) {
#define COMPACT(e)      t = e; while (*p++ = *t++);
                /* Create insecure data. */
                p = buf;
                COMPACT(pwd.pw_name);
                COMPACT("*");
                memmove(p, &pwd.pw_uid, sizeof(int));
                p += sizeof(int);
                memmove(p, &pwd.pw_gid, sizeof(int));
                p += sizeof(int);
                memmove(p, &pwd.pw_change, sizeof(time_t));
                p += sizeof(time_t);
                COMPACT(pwd.pw_class);
                COMPACT(pwd.pw_gecos);
                COMPACT(pwd.pw_dir);
                COMPACT(pwd.pw_shell);
                memmove(p, &pwd.pw_expire, sizeof(time_t));
                p += sizeof(time_t);
                data.size = p - buf;

                /* Store insecure by name. */
                tbuf[0] = _PW_KEYBYNAME;
                len = strlen(pwd.pw_name);
                memmove(tbuf + 1, pwd.pw_name, len);
                key.size = len + 1;
                if ((dp->put)(dp, &key, &data, R_NOOVERWRITE) == -1)
                        error("put");

                /* Store insecure by number. */
                tbuf[0] = _PW_KEYBYNUM;
                memmove(tbuf + 1, &cnt, sizeof(cnt));
                key.size = sizeof(cnt) + 1;
                if ((dp->put)(dp, &key, &data, R_NOOVERWRITE) == -1)
                        error("put");

                /* Store insecure by uid. */
                tbuf[0] = _PW_KEYBYUID;
                memmove(tbuf + 1, &pwd.pw_uid, sizeof(pwd.pw_uid));
                key.size = sizeof(pwd.pw_uid) + 1;
                if ((dp->put)(dp, &key, &data, R_NOOVERWRITE) == -1)
                        error("put");

                /* Create original format password file entry */
                if (makeold)
                        (void)fprintf(oldfp, "%s:*:%d:%d:%s:%s:%s\n",
                            pwd.pw_name, pwd.pw_uid, pwd.pw_gid, pwd.pw_gecos,
                            pwd.pw_dir, pwd.pw_shell);
        }
        (void)(dp->close)(dp);
        if (makeold) {
                (void)fflush(oldfp);
                (void)fclose(oldfp);
        }

        /* Open the temporary encrypted password database. */
        (void)snprintf(buf, sizeof(buf), "%s.tmp", _PATH_SMP_DB);
        edp = dbopen(buf,
            O_RDWR|O_CREAT|O_EXCL, PERM_SECURE, DB_HASH, &openinfo);
        if (!edp)
                error(buf);
        clean = FILE_SECURE;

        rewind(fp);
        for (cnt = 1; scan(fp, &pwd); ++cnt) {

                /* Create secure data. */
                p = buf;
                COMPACT(pwd.pw_name);
                COMPACT(pwd.pw_passwd);
                memmove(p, &pwd.pw_uid, sizeof(int));
                p += sizeof(int);
                memmove(p, &pwd.pw_gid, sizeof(int));
                p += sizeof(int);
                memmove(p, &pwd.pw_change, sizeof(time_t));
                p += sizeof(time_t);
                COMPACT(pwd.pw_class);
                COMPACT(pwd.pw_gecos);
                COMPACT(pwd.pw_dir);
                COMPACT(pwd.pw_shell);
                memmove(p, &pwd.pw_expire, sizeof(time_t));
                p += sizeof(time_t);
                data.size = p - buf;

                /* Store secure by name. */
                tbuf[0] = _PW_KEYBYNAME;
                len = strlen(pwd.pw_name);
                memmove(tbuf + 1, pwd.pw_name, len);
                key.size = len + 1;
                if ((dp->put)(edp, &key, &data, R_NOOVERWRITE) == -1)
                        error("put");

                /* Store secure by number. */
                tbuf[0] = _PW_KEYBYNUM;
                memmove(tbuf + 1, &cnt, sizeof(cnt));
                key.size = sizeof(cnt) + 1;
                if ((dp->put)(edp, &key, &data, R_NOOVERWRITE) == -1)
                        error("put");

                /* Store secure by uid. */
                tbuf[0] = _PW_KEYBYUID;
                memmove(tbuf + 1, &pwd.pw_uid, sizeof(pwd.pw_uid));
                key.size = sizeof(pwd.pw_uid) + 1;
                if ((dp->put)(edp, &key, &data, R_NOOVERWRITE) == -1)
                        error("put");
        }

        (void)(edp->close)(edp);

        /* Set master.passwd permissions, in case caller forgot. */
        (void)fchmod(fileno(fp), S_IRUSR|S_IWUSR);
        (void)fclose(fp);

        /* Install as the real password files. */
        (void)snprintf(buf, sizeof(buf), "%s.tmp", _PATH_MP_DB);
        mv(buf, _PATH_MP_DB);
        (void)snprintf(buf, sizeof(buf), "%s.tmp", _PATH_SMP_DB);
        mv(buf, _PATH_SMP_DB);
        if (makeold) {
                (void)snprintf(buf, sizeof(buf), "%s.orig", pname);
                mv(buf, _PATH_PASSWD);
        }
        /*
         * Move the master password LAST -- chpass(1), passwd(1) and vipw(8)
         * all use flock(2) on it to block other incarnations of themselves.
         * The rename means that everything is unlocked, as the original file
         * can no longer be accessed.
         */
        mv(pname, _PATH_MASTERPASSWD);
        exit(0);
}

int
scan(fp, pw)
        FILE *fp;
        struct passwd *pw;
{
        static int lcnt;
        static char line[LINE_MAX];
        char *p;

        if (!fgets(line, sizeof(line), fp))
                return (0);
        ++lcnt;
        /*
         * ``... if I swallow anything evil, put your fingers down my
         * throat...''
         *      -- The Who
         */
        if (!(p = strchr(line, '\n'))) {
                warnx("line too long");
                goto fmt;

        }
        *p = '\0';
        if (!pw_scan(line, pw)) {
                warnx("at line #%d", lcnt);
fmt:            errno = EFTYPE; /* XXX */
                error(pname);
        }

        return (1);
}

void
mv(from, to)
        char *from, *to;
{
        char buf[MAXPATHLEN];

        if (rename(from, to)) {
                int sverrno = errno;
                (void)snprintf(buf, sizeof(buf), "%s to %s", from, to);
                errno = sverrno;
                error(buf);
        }
}

void
error(name)
        char *name;
{

        warn(name);
        cleanup();
        exit(1);
}

void
cleanup()
{
        char buf[MAXPATHLEN];

        switch(clean) {
        case FILE_ORIG:
                (void)snprintf(buf, sizeof(buf), "%s.orig", pname);
                (void)unlink(buf);
                /* FALLTHROUGH */
        case FILE_SECURE:
                (void)snprintf(buf, sizeof(buf), "%s.tmp", _PATH_SMP_DB);
                (void)unlink(buf);
                /* FALLTHROUGH */
        case FILE_INSECURE:
                (void)snprintf(buf, sizeof(buf), "%s.tmp", _PATH_MP_DB);
                (void)unlink(buf);
        }
}

void
usage()
{

        (void)fprintf(stderr, "usage: pwd_mkdb [-p] file\n");
        exit(1);
}