1 /*	$OpenBSD: ssl.c,v 1.40 2026/05/21 14:56:34 tb Exp $	*/
2 
3 /*
4  * Copyright (c) 2007 - 2014 Reyk Floeter <reyk@openbsd.org>
5  * Copyright (c) 2006 Pierre-Yves Ritschard <pyr@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/types.h>
21 #include <sys/queue.h>
22 #include <sys/uio.h>
23 
24 #include <unistd.h>
25 #include <string.h>
26 #include <imsg.h>
27 
28 #include <openssl/ssl.h>
29 #include <openssl/err.h>
30 
31 #include "relayd.h"
32 #include "log.h"
33 
34 int	ssl_password_cb(char *, int, int, void *);
35 
36 int
37 ssl_password_cb(char *buf, int size, int rwflag, void *u)
38 {
39 	size_t	len;
40 	if (u == NULL) {
41 		explicit_bzero(buf, size);
42 		return (0);
43 	}
44 	if ((len = strlcpy(buf, u, size)) >= (size_t)size) {
45 		explicit_bzero(buf, size);
46 		return (0);
47 	}
48 	return (len);
49 }
50 
51 char *
52 ssl_load_key(struct relayd *env, const char *name, off_t *len, char *pass)
53 {
54 	FILE		*fp;
55 	EVP_PKEY	*key = NULL;
56 	BIO		*bio = NULL;
57 	long		 size;
58 	char		*data, *buf = NULL;
59 
60 	/*
61 	 * Read (possibly) encrypted key from file
62 	 */
63 	if ((fp = fopen(name, "r")) == NULL)
64 		return (NULL);
65 
66 	key = PEM_read_PrivateKey(fp, NULL, ssl_password_cb, pass);
67 	fclose(fp);
68 	if (key == NULL)
69 		goto fail;
70 
71 	/*
72 	 * Write unencrypted key to memory buffer
73 	 */
74 	if ((bio = BIO_new(BIO_s_mem())) == NULL)
75 		goto fail;
76 	if (!PEM_write_bio_PrivateKey(bio, key, NULL, NULL, 0, NULL, NULL))
77 		goto fail;
78 	if ((size = BIO_get_mem_data(bio, &data)) <= 0)
79 		goto fail;
80 	if ((buf = calloc(1, size)) == NULL)
81 		goto fail;
82 	memcpy(buf, data, size);
83 
84 	BIO_free_all(bio);
85 	EVP_PKEY_free(key);
86 
87 	*len = (off_t)size;
88 	return (buf);
89 
90  fail:
91 	free(buf);
92 	if (bio != NULL)
93 		BIO_free_all(bio);
94 	if (key != NULL)
95 		EVP_PKEY_free(key);
96 	return (NULL);
97 }
98 
99 uint8_t *
100 ssl_update_certificate(const uint8_t *oldcert, size_t oldlen, EVP_PKEY *pkey,
101     EVP_PKEY *capkey, X509 *cacert, size_t *newlen)
102 {
103 	char		 name[2][TLS_NAME_SIZE];
104 	BIO		*in, *out = NULL;
105 	BUF_MEM		*bptr = NULL;
106 	X509		*cert = NULL;
107 	uint8_t		*newcert = NULL;
108 
109 	if ((in = BIO_new_mem_buf(oldcert, oldlen)) == NULL) {
110 		log_warnx("%s: BIO_new_mem_buf failed", __func__);
111 		goto done;
112 	}
113 
114 	if ((cert = PEM_read_bio_X509(in, NULL,
115 	    ssl_password_cb, NULL)) == NULL) {
116 		log_warnx("%s: PEM_read_bio_X509 failed", __func__);
117 		goto done;
118 	}
119 
120 	BIO_free(in);
121 	in = NULL;
122 
123 	name[0][0] = name[1][0] = '\0';
124 	if (!X509_NAME_oneline(X509_get_subject_name(cert),
125 	    name[0], sizeof(name[0])) ||
126 	    !X509_NAME_oneline(X509_get_issuer_name(cert),
127 	    name[1], sizeof(name[1])))
128 		goto done;
129 
130 	/* Update certificate key and use our CA as the issuer */
131 	if (!X509_set_pubkey(cert, pkey)) {
132 		log_warnx("%s: X509_set_pubkey failed", __func__);
133 		goto done;
134 	}
135 	if (!X509_set_issuer_name(cert, X509_get_subject_name(cacert))) {
136 		log_warnx("%s: X509_get_issuer_name failed", __func__);
137 		goto done;
138 	}
139 
140 	/* Sign with our CA */
141 	if (!X509_sign(cert, capkey, EVP_sha256())) {
142 		log_warnx("%s: X509_sign failed", __func__);
143 		goto done;
144 	}
145 
146 #if DEBUG_CERT
147 	log_debug("%s: subject %s", __func__, name[0]);
148 	log_debug("%s: issuer %s", __func__, name[1]);
149 #if DEBUG > 2
150 	X509_print_fp(stdout, cert);
151 #endif
152 #endif
153 
154 	/* write cert as PEM file */
155 	out = BIO_new(BIO_s_mem());
156 	if (out == NULL) {
157 		log_warnx("%s: BIO_new failed", __func__);
158 		goto done;
159 	}
160 	if (!PEM_write_bio_X509(out, cert)) {
161 		log_warnx("%s: PEM_write_bio_X509 failed", __func__);
162 		goto done;
163 	}
164 	BIO_get_mem_ptr(out, &bptr);
165 	if ((newcert = malloc(bptr->length)) == NULL) {
166 		log_warn("%s: malloc", __func__);
167 		goto done;
168 	}
169 	memcpy(newcert, bptr->data, bptr->length);
170 	*newlen = bptr->length;
171 
172 done:
173 	if (in)
174 		BIO_free(in);
175 	if (out)
176 		BIO_free(out);
177 	if (cert)
178 		X509_free(cert);
179 	return (newcert);
180 }
181 
182 int
183 ssl_load_pkey(char *buf, off_t len, X509 **x509ptr, EVP_PKEY **pkeyptr)
184 {
185 	BIO		*in;
186 	X509		*x509 = NULL;
187 	EVP_PKEY	*pkey = NULL;
188 	RSA		*rsa = NULL;
189 	char		*hash = NULL;
190 
191 	if ((in = BIO_new_mem_buf(buf, len)) == NULL) {
192 		log_warnx("%s: BIO_new_mem_buf failed", __func__);
193 		return (0);
194 	}
195 	if ((x509 = PEM_read_bio_X509(in, NULL,
196 	    ssl_password_cb, NULL)) == NULL) {
197 		log_warnx("%s: PEM_read_bio_X509 failed", __func__);
198 		goto fail;
199 	}
200 	if ((pkey = X509_get_pubkey(x509)) == NULL) {
201 		log_warnx("%s: X509_get_pubkey failed", __func__);
202 		goto fail;
203 	}
204 	if ((rsa = EVP_PKEY_get1_RSA(pkey)) == NULL) {
205 		log_warnx("%s: failed to extract RSA", __func__);
206 		goto fail;
207 	}
208 	if ((hash = malloc(TLS_CERT_HASH_SIZE)) == NULL) {
209 		log_warn("%s: allocate hash failed", __func__);
210 		goto fail;
211 	}
212 	hash_x509(x509, hash, TLS_CERT_HASH_SIZE);
213 	if (RSA_set_ex_data(rsa, 0, hash) != 1) {
214 		log_warnx("%s: failed to set hash as exdata", __func__);
215 		goto fail;
216 	}
217 
218 	RSA_free(rsa); /* dereference, will be cleaned up with pkey */
219 	*pkeyptr = pkey;
220 	if (x509ptr != NULL)
221 		*x509ptr = x509;
222 	else
223 		X509_free(x509);
224 	BIO_free(in);
225 
226 	return (1);
227 
228  fail:
229 	free(hash);
230 	if (rsa != NULL)
231 		RSA_free(rsa);
232 	if (pkey != NULL)
233 		EVP_PKEY_free(pkey);
234 	if (x509 != NULL)
235 		X509_free(x509);
236 	BIO_free(in);
237 
238 	return (0);
239 }