ssl_init.c revision 330141 
1/*
2 * ssl_init.c	Common OpenSSL initialization code for the various
3 *		programs which use it.
4 *
5 * Moved from ntpd/ntp_crypto.c crypto_setup()
6 */
7#ifdef HAVE_CONFIG_H
8# include <config.h>
9#endif
10#include <ctype.h>
11#include <ntp.h>
12#include <ntp_debug.h>
13#include <lib_strbuf.h>
14
15#ifdef OPENSSL
16# include "openssl/cmac.h"
17# include "openssl/crypto.h"
18# include "openssl/err.h"
19# include "openssl/evp.h"
20# include "openssl/opensslv.h"
21# include "libssl_compat.h"
22
23# define CMAC_LENGTH	16
24# define CMAC		"AES128CMAC"
25
26int ssl_init_done;
27
28#if OPENSSL_VERSION_NUMBER < 0x10100000L
29
30static void
31atexit_ssl_cleanup(void)
32{
33	if (!ssl_init_done) {
34		return;
35	}
36
37	ssl_init_done = FALSE;
38	EVP_cleanup();
39	ERR_free_strings();
40}
41
42void
43ssl_init(void)
44{
45	init_lib();
46
47	if ( ! ssl_init_done) {
48	    ERR_load_crypto_strings();
49	    OpenSSL_add_all_algorithms();
50	    atexit(&atexit_ssl_cleanup);
51	    ssl_init_done = TRUE;
52	}
53}
54
55#else /* OPENSSL_VERSION_NUMBER >= 0x10100000L */
56
57void
58ssl_init(void)
59{
60	init_lib();
61	ssl_init_done = TRUE;
62}
63
64#endif /* OPENSSL_VERSION_NUMBER */
65
66
67void
68ssl_check_version(void)
69{
70	u_long	v;
71
72	v = OpenSSL_version_num();
73	if ((v ^ OPENSSL_VERSION_NUMBER) & ~0xff0L) {
74		msyslog(LOG_WARNING,
75		    "OpenSSL version mismatch. Built against %lx, you have %lx",
76		    (u_long)OPENSSL_VERSION_NUMBER, v);
77		fprintf(stderr,
78		    "OpenSSL version mismatch. Built against %lx, you have %lx\n",
79		    (u_long)OPENSSL_VERSION_NUMBER, v);
80	}
81
82	INIT_SSL();
83}
84
85#else	/* !OPENSSL */
86# define MD5_LENGTH	16
87#endif	/* OPENSSL */
88
89
90/*
91 * keytype_from_text	returns OpenSSL NID for digest by name, and
92 *			optionally the associated digest length.
93 *
94 * Used by ntpd authreadkeys(), ntpq and ntpdc keytype()
95 */
96int
97keytype_from_text(
98	const char *	text,
99	size_t *	pdigest_len
100	)
101{
102	int		key_type;
103	u_int		digest_len;
104#ifdef OPENSSL	/* --*-- OpenSSL code --*-- */
105	const u_long	max_digest_len = MAX_MAC_LEN - sizeof(keyid_t);
106	char *		upcased;
107	char *		pch;
108	EVP_MD const *	md;
109
110	/*
111	 * OpenSSL digest short names are capitalized, so uppercase the
112	 * digest name before passing to OBJ_sn2nid().  If it is not
113	 * recognized but matches our CMAC string use NID_cmac, or if
114	 * it begins with 'M' or 'm' use NID_md5 to be consistent with
115	 * past behavior.
116	 */
117	INIT_SSL();
118
119	/* get name in uppercase */
120	LIB_GETBUF(upcased);
121	strlcpy(upcased, text, LIB_BUFLENGTH);
122
123	for (pch = upcased; '\0' != *pch; pch++) {
124		*pch = (char)toupper((unsigned char)*pch);
125	}
126
127	key_type = OBJ_sn2nid(upcased);
128
129	if (!key_type && !strncmp(CMAC, upcased, strlen(CMAC) + 1)) {
130		key_type = NID_cmac;
131
132		if (debug) {
133			fprintf(stderr, "%s:%d:%s():%s:key\n",
134				__FILE__, __LINE__, __func__, CMAC);
135		}
136	}
137#else
138
139	key_type = 0;
140#endif
141
142	if (!key_type && 'm' == tolower((unsigned char)text[0])) {
143		key_type = NID_md5;
144	}
145
146	if (!key_type) {
147		return 0;
148	}
149
150	if (NULL != pdigest_len) {
151#ifdef OPENSSL
152		md = EVP_get_digestbynid(key_type);
153		digest_len = (md) ? EVP_MD_size(md) : 0;
154
155		if (!md || digest_len <= 0) {
156		    if (key_type == NID_cmac) {
157			digest_len = CMAC_LENGTH;
158
159			if (debug) {
160				fprintf(stderr, "%s:%d:%s():%s:len\n",
161					__FILE__, __LINE__, __func__, CMAC);
162			}
163		    } else {
164			fprintf(stderr,
165				"key type %s is not supported by OpenSSL\n",
166				keytype_name(key_type));
167			msyslog(LOG_ERR,
168				"key type %s is not supported by OpenSSL\n",
169				keytype_name(key_type));
170			return 0;
171		    }
172		}
173
174		if (digest_len > max_digest_len) {
175		    fprintf(stderr,
176			    "key type %s %u octet digests are too big, max %lu\n",
177			    keytype_name(key_type), digest_len,
178			    max_digest_len);
179		    msyslog(LOG_ERR,
180			    "key type %s %u octet digests are too big, max %lu",
181			    keytype_name(key_type), digest_len,
182			    max_digest_len);
183		    return 0;
184		}
185#else
186		digest_len = MD5_LENGTH;
187#endif
188		*pdigest_len = digest_len;
189	}
190
191	return key_type;
192}
193
194
195/*
196 * keytype_name		returns OpenSSL short name for digest by NID.
197 *
198 * Used by ntpq and ntpdc keytype()
199 */
200const char *
201keytype_name(
202	int nid
203	)
204{
205	static const char unknown_type[] = "(unknown key type)";
206	const char *name;
207
208#ifdef OPENSSL
209	INIT_SSL();
210	name = OBJ_nid2sn(nid);
211
212	if (NID_cmac == nid) {
213		name = CMAC;
214
215		if (debug) {
216			fprintf(stderr, "%s:%d:%s():%s:nid\n",
217				__FILE__, __LINE__, __func__, CMAC);
218		}
219	} else
220	if (NULL == name) {
221		name = unknown_type;
222	}
223#else	/* !OPENSSL follows */
224	if (NID_md5 == nid)
225		name = "MD5";
226	else
227		name = unknown_type;
228#endif
229	return name;
230}
231
232
233/*
234 * Use getpassphrase() if configure.ac detected it, as Suns that
235 * have it truncate the password in getpass() to 8 characters.
236 */
237#ifdef HAVE_GETPASSPHRASE
238# define	getpass(str)	getpassphrase(str)
239#endif
240
241/*
242 * getpass_keytype() -- shared between ntpq and ntpdc, only vaguely
243 *			related to the rest of ssl_init.c.
244 */
245char *
246getpass_keytype(
247	int	keytype
248	)
249{
250	char	pass_prompt[64 + 11 + 1]; /* 11 for " Password: " */
251
252	snprintf(pass_prompt, sizeof(pass_prompt),
253		 "%.64s Password: ", keytype_name(keytype));
254
255	return getpass(pass_prompt);
256}
257
258