xref: /freebsd/crypto/heimdal/kdc/kstash.c (revision 81ad626541db97eb356e2c1d4a20eb2a26a766ab)
1 /*
2  * Copyright (c) 1997-2004 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "headers.h"
35 
36 krb5_context context;
37 
38 static char *keyfile;
39 static int convert_flag;
40 static int help_flag;
41 static int version_flag;
42 
43 static int master_key_fd = -1;
44 static int random_key_flag;
45 
46 static const char *enctype_str = "des3-cbc-sha1";
47 
48 static struct getargs args[] = {
49     { "enctype", 'e', arg_string, rk_UNCONST(&enctype_str), "encryption type",
50 	NULL },
51     { "key-file", 'k', arg_string, &keyfile, "master key file", "file" },
52     { "convert-file", 0, arg_flag, &convert_flag,
53       "just convert keyfile to new format", NULL },
54     { "master-key-fd", 0, arg_integer, &master_key_fd,
55       "filedescriptor to read passphrase from", "fd" },
56     { "random-key", 0, arg_flag, &random_key_flag,
57 	"generate a random master key", NULL },
58     { "help", 'h', arg_flag, &help_flag, NULL, NULL },
59     { "version", 0, arg_flag, &version_flag, NULL, NULL }
60 };
61 
62 int num_args = sizeof(args) / sizeof(args[0]);
63 
64 int
65 main(int argc, char **argv)
66 {
67     char buf[1024];
68     krb5_error_code ret;
69 
70     krb5_enctype enctype;
71 
72     hdb_master_key mkey;
73 
74     krb5_program_setup(&context, argc, argv, args, num_args, NULL);
75 
76     if(help_flag)
77 	krb5_std_usage(0, args, num_args);
78     if(version_flag){
79 	print_version(NULL);
80 	exit(0);
81     }
82 
83     if (master_key_fd != -1 && random_key_flag)
84 	krb5_errx(context, 1, "random-key and master-key-fd "
85 		  "is mutual exclusive");
86 
87     if (keyfile == NULL)
88 	asprintf(&keyfile, "%s/m-key", hdb_db_dir(context));
89 
90     ret = krb5_string_to_enctype(context, enctype_str, &enctype);
91     if(ret)
92 	krb5_err(context, 1, ret, "krb5_string_to_enctype");
93 
94     ret = hdb_read_master_key(context, keyfile, &mkey);
95     if(ret && ret != ENOENT)
96 	krb5_err(context, 1, ret, "reading master key from %s", keyfile);
97 
98     if (convert_flag) {
99 	if (ret)
100 	    krb5_err(context, 1, ret, "reading master key from %s", keyfile);
101     } else {
102 	krb5_keyblock key;
103 	krb5_salt salt;
104 	salt.salttype = KRB5_PW_SALT;
105 	/* XXX better value? */
106 	salt.saltvalue.data = NULL;
107 	salt.saltvalue.length = 0;
108 	if (random_key_flag) {
109 	    ret = krb5_generate_random_keyblock(context, enctype, &key);
110 	    if (ret)
111 		krb5_err(context, 1, ret, "krb5_generate_random_keyblock");
112 
113 	} else {
114 	    if(master_key_fd != -1) {
115 		ssize_t n;
116 		n = read(master_key_fd, buf, sizeof(buf));
117 		if(n <= 0)
118 		    krb5_err(context, 1, errno, "failed to read passphrase");
119 		buf[n] = '\0';
120 		buf[strcspn(buf, "\r\n")] = '\0';
121 
122 	    } else {
123 		if(UI_UTIL_read_pw_string(buf, sizeof(buf), "Master key: ", 1))
124 		    exit(1);
125 	    }
126 	    krb5_string_to_key_salt(context, enctype, buf, salt, &key);
127 	}
128 	ret = hdb_add_master_key(context, &key, &mkey);
129         if (ret)
130             krb5_err(context, 1, ret, "hdb_add_master_key");
131 
132 	krb5_free_keyblock_contents(context, &key);
133 
134     }
135 
136     {
137 	char *new, *old;
138 	asprintf(&old, "%s.old", keyfile);
139 	asprintf(&new, "%s.new", keyfile);
140 	if(unlink(new) < 0 && errno != ENOENT) {
141 	    ret = errno;
142 	    goto out;
143 	}
144 	krb5_warnx(context, "writing key to `%s'", keyfile);
145 	ret = hdb_write_master_key(context, new, mkey);
146 	if(ret)
147 	    unlink(new);
148 	else {
149 #ifndef NO_POSIX_LINKS
150 	    unlink(old);
151 	    if(link(keyfile, old) < 0 && errno != ENOENT) {
152 		ret = errno;
153 		unlink(new);
154 	    } else {
155 #endif
156 		if(rename(new, keyfile) < 0) {
157 		    ret = errno;
158 		}
159 #ifndef NO_POSIX_LINKS
160 	    }
161 #endif
162 	}
163     out:
164 	free(old);
165 	free(new);
166 	if(ret)
167 	    krb5_warn(context, errno, "writing master key file");
168     }
169 
170     hdb_free_master_key(context, mkey);
171 
172     exit(ret != 0);
173 }
174