heimdal/kadmin/stash.c

/*
 * Copyright (c) 2004 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden). 
 * 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. Neither the name of the Institute nor the names of its contributors 
 *    may be used to endorse or promote products derived from this software 
 *    without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 THE INSTITUTE 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 "kadmin_locl.h"
#include "kadmin-commands.h"

RCSID("$Id$");

extern int local_flag;

int
stash(struct stash_options *opt, int argc, char **argv)
{
    char buf[1024];
    krb5_error_code ret;
    krb5_enctype enctype;
    hdb_master_key mkey;
    
    if(!local_flag) {
	krb5_warnx(context, "stash is only available in local (-l) mode");
	return 0;
    }

    ret = krb5_string_to_enctype(context, opt->enctype_string, &enctype);
    if(ret) {
	krb5_warn(context, ret, "%s", opt->enctype_string);
	return 0;
    }

    if(opt->key_file_string == NULL)
	opt->key_file_string = HDB_DB_DIR "/m-key";

    ret = hdb_read_master_key(context, opt->key_file_string, &mkey);
    if(ret && ret != ENOENT) {
	krb5_warn(context, ret, "reading master key from %s", 
		  opt->key_file_string);
	return 0;
    }

    if (opt->convert_file_flag) {
	if (ret)
	    krb5_warn(context, ret, "reading master key from %s", 
		      opt->key_file_string);
	return 0;
    } else {
	krb5_keyblock key;
	krb5_salt salt;
	salt.salttype = KRB5_PW_SALT;
	/* XXX better value? */
	salt.saltvalue.data = NULL;
	salt.saltvalue.length = 0;
	if(opt->master_key_fd_integer != -1) {
	    ssize_t n;
	    n = read(opt->master_key_fd_integer, buf, sizeof(buf));
	    if(n == 0)
		krb5_warnx(context, "end of file reading passphrase");
	    else if(n < 0)
		krb5_warn(context, errno, "reading passphrase");
	    buf[n] = '\0';
	    buf[strcspn(buf, "\r\n")] = '\0';
	} else {
	    if(UI_UTIL_read_pw_string(buf, sizeof(buf), "Master key: ", 1)) {
		hdb_free_master_key(context, mkey);
		return 0;
	    }
	}
	ret = krb5_string_to_key_salt(context, enctype, buf, salt, &key);
	ret = hdb_add_master_key(context, &key, &mkey);
	krb5_free_keyblock_contents(context, &key);
    }
    
    {
	char *new, *old;
	asprintf(&old, "%s.old", opt->key_file_string);
	asprintf(&new, "%s.new", opt->key_file_string);
	if(old == NULL || new == NULL) {
	    ret = ENOMEM;
	    goto out;
	}
	    
	if(unlink(new) < 0 && errno != ENOENT) {
	    ret = errno;
	    goto out;
	}
	krb5_warnx(context, "writing key to \"%s\"", opt->key_file_string);
	ret = hdb_write_master_key(context, new, mkey);
	if(ret)
	    unlink(new);
	else {
	    unlink(old);
	    if(link(opt->key_file_string, old) < 0 && errno != ENOENT) {
		ret = errno;
		unlink(new);
	    } else if(rename(new, opt->key_file_string) < 0) {
		ret = errno;
	    }
	}
    out:
	free(old);
	free(new);
	if(ret)
	    krb5_warn(context, errno, "writing master key file");
    }

    hdb_free_master_key(context, mkey);
    return 0;
}