2 * Copyright (c) 2007, Cameron Rich
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
9 * * Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 * * Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 * * Neither the name of the axTLS project nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
22 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
23 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
24 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
25 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
26 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
27 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
28 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 #ifdef CONFIG_SSL_GENERATE_X509_CERT
39 * Generate a basic X.509 certificate
42 static uint8_t set_gen_length(int len
, uint8_t *buf
, int *offset
)
44 if (len
< 0x80) /* short form */
46 buf
[(*offset
)++] = len
;
51 int i
, length_bytes
= 0;
55 else if (len
& 0x0000FF00)
57 else if (len
& 0x000000FF)
60 buf
[(*offset
)++] = 0x80 + length_bytes
;
62 for (i
= length_bytes
-1; i
>= 0; i
--)
64 buf
[*offset
+i
] = len
& 0xFF;
68 *offset
+= length_bytes
;
69 return length_bytes
+1;
73 static int pre_adjust_with_size(uint8_t type
,
74 int *seq_offset
, uint8_t *buf
, int *offset
)
76 buf
[(*offset
)++] = type
;
77 *seq_offset
= *offset
;
78 *offset
+= 4; /* fill in later */
82 static void adjust_with_size(int seq_size
, int seq_start
,
83 uint8_t *buf
, int *offset
)
85 uint8_t seq_byte_size
;
86 int orig_seq_size
= seq_size
;
87 int orig_seq_start
= seq_start
;
89 seq_size
= *offset
-seq_size
;
90 seq_byte_size
= set_gen_length(seq_size
, buf
, &seq_start
);
92 if (seq_byte_size
!= 4)
94 memmove(&buf
[orig_seq_start
+seq_byte_size
],
95 &buf
[orig_seq_size
], seq_size
);
96 *offset
-= 4-seq_byte_size
;
100 static void gen_serial_number(uint8_t *buf
, int *offset
)
102 static const uint8_t ser_oid
[] = { ASN1_INTEGER
, 1, 0x7F };
103 memcpy(&buf
[*offset
], ser_oid
, sizeof(ser_oid
));
104 *offset
+= sizeof(ser_oid
);
107 static void gen_signature_alg(uint8_t *buf
, int *offset
)
109 /* OBJECT IDENTIFIER sha1withRSAEncryption (1 2 840 113549 1 1 5) */
110 static const uint8_t sig_oid
[] =
112 ASN1_SEQUENCE
, 0x0d, ASN1_OID
, 0x09,
113 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x05,
117 memcpy(&buf
[*offset
], sig_oid
, sizeof(sig_oid
));
118 *offset
+= sizeof(sig_oid
);
121 static int gen_dn(const char *name
, uint8_t dn_type
,
122 uint8_t *buf
, int *offset
)
125 int name_size
= strlen(name
);
127 if (name_size
> 0x70) /* just too big */
133 buf
[(*offset
)++] = ASN1_SET
;
134 set_gen_length(9+name_size
, buf
, offset
);
135 buf
[(*offset
)++] = ASN1_SEQUENCE
;
136 set_gen_length(7+name_size
, buf
, offset
);
137 buf
[(*offset
)++] = ASN1_OID
;
138 buf
[(*offset
)++] = 3;
139 buf
[(*offset
)++] = 0x55;
140 buf
[(*offset
)++] = 0x04;
141 buf
[(*offset
)++] = dn_type
;
142 buf
[(*offset
)++] = ASN1_PRINTABLE_STR
;
143 buf
[(*offset
)++] = name_size
;
144 strcpy(&buf
[*offset
], name
);
145 *offset
+= name_size
;
151 static int gen_issuer(const char * dn
[], uint8_t *buf
, int *offset
)
155 int seq_size
= pre_adjust_with_size(
156 ASN1_SEQUENCE
, &seq_offset
, buf
, offset
);
159 /* we need the common name, so if not configured, work out the fully
160 * qualified domain name */
161 if (dn
[X509_COMMON_NAME
] == NULL
|| strlen(dn
[X509_COMMON_NAME
]) == 0)
164 gethostname(fqdn
, sizeof(fqdn
));
165 fqdn_len
= strlen(fqdn
);
166 fqdn
[fqdn_len
++] = '.';
167 getdomainname(&fqdn
[fqdn_len
], sizeof(fqdn
)-fqdn_len
);
168 fqdn_len
= strlen(fqdn
);
170 if (fqdn
[fqdn_len
-1] == '.') /* ensure '.' is not last char */
171 fqdn
[fqdn_len
-1] = 0;
173 dn
[X509_COMMON_NAME
] = fqdn
;
176 if ((ret
= gen_dn(dn
[X509_COMMON_NAME
], 3, buf
, offset
)))
179 if (dn
[X509_ORGANIZATION
] != NULL
&& strlen(dn
[X509_ORGANIZATION
]) > 0)
181 if ((ret
= gen_dn(dn
[X509_ORGANIZATION
], 10, buf
, offset
)))
185 if (dn
[X509_ORGANIZATIONAL_UNIT
] != NULL
&&
186 strlen(dn
[X509_ORGANIZATIONAL_UNIT
]) > 0)
188 if ((ret
= gen_dn(dn
[X509_ORGANIZATIONAL_UNIT
], 11, buf
, offset
)))
192 adjust_with_size(seq_size
, seq_offset
, buf
, offset
);
198 static void gen_utc_time(uint8_t *buf
, int *offset
)
200 static const uint8_t time_seq
[] =
204 '0', '7', '0', '1', '0', '1', '0', '0', '0', '0', '0', '0', 'Z',
205 ASN1_UTC_TIME
, 13, /* make it good for 30 or so years */
206 '3', '8', '0', '1', '0', '1', '0', '0', '0', '0', '0', '0', 'Z'
210 memcpy(&buf
[*offset
], time_seq
, sizeof(time_seq
));
211 *offset
+= sizeof(time_seq
);
214 static void gen_pub_key2(const RSA_CTX
*rsa_ctx
, uint8_t *buf
, int *offset
)
216 static const uint8_t pub_key_seq
[] =
218 ASN1_INTEGER
, 0x03, 0x01, 0x00, 0x01 /* INTEGER 65537 */
222 int pub_key_size
= rsa_ctx
->num_octets
;
223 uint8_t *block
= (uint8_t *)alloca(pub_key_size
);
224 int seq_size
= pre_adjust_with_size(
225 ASN1_SEQUENCE
, &seq_offset
, buf
, offset
);
226 buf
[(*offset
)++] = ASN1_INTEGER
;
227 bi_export(rsa_ctx
->bi_ctx
, rsa_ctx
->m
, block
, pub_key_size
);
229 if (*block
& 0x80) /* make integer positive */
231 set_gen_length(pub_key_size
+1, buf
, offset
);
232 buf
[(*offset
)++] = 0;
235 set_gen_length(pub_key_size
, buf
, offset
);
237 memcpy(&buf
[*offset
], block
, pub_key_size
);
238 *offset
+= pub_key_size
;
239 memcpy(&buf
[*offset
], pub_key_seq
, sizeof(pub_key_seq
));
240 *offset
+= sizeof(pub_key_seq
);
241 adjust_with_size(seq_size
, seq_offset
, buf
, offset
);
244 static void gen_pub_key1(const RSA_CTX
*rsa_ctx
, uint8_t *buf
, int *offset
)
247 int seq_size
= pre_adjust_with_size(
248 ASN1_BIT_STRING
, &seq_offset
, buf
, offset
);
249 buf
[(*offset
)++] = 0; /* bit string is multiple of 8 */
250 gen_pub_key2(rsa_ctx
, buf
, offset
);
251 adjust_with_size(seq_size
, seq_offset
, buf
, offset
);
254 static void gen_pub_key(const RSA_CTX
*rsa_ctx
, uint8_t *buf
, int *offset
)
256 /* OBJECT IDENTIFIER rsaEncryption (1 2 840 113549 1 1 1) */
257 static const uint8_t rsa_enc_oid
[] =
259 ASN1_SEQUENCE
, 0x0d, ASN1_OID
, 0x09,
260 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01,
265 int seq_size
= pre_adjust_with_size(
266 ASN1_SEQUENCE
, &seq_offset
, buf
, offset
);
268 memcpy(&buf
[*offset
], rsa_enc_oid
, sizeof(rsa_enc_oid
));
269 *offset
+= sizeof(rsa_enc_oid
);
270 gen_pub_key1(rsa_ctx
, buf
, offset
);
271 adjust_with_size(seq_size
, seq_offset
, buf
, offset
);
274 static void gen_signature(const RSA_CTX
*rsa_ctx
, const uint8_t *sha_dgst
,
275 uint8_t *buf
, int *offset
)
277 static const uint8_t asn1_sig
[] =
279 ASN1_SEQUENCE
, 0x21, ASN1_SEQUENCE
, 0x09, ASN1_OID
, 0x05,
280 0x2b, 0x0e, 0x03, 0x02, 0x1a, /* sha1 (1 3 14 3 2 26) */
281 ASN1_NULL
, 0x00, ASN1_OCTET_STRING
, 0x14
284 uint8_t *enc_block
= (uint8_t *)alloca(rsa_ctx
->num_octets
);
285 uint8_t *block
= (uint8_t *)alloca(sizeof(asn1_sig
) + SHA1_SIZE
);
288 /* add the digest as an embedded asn.1 sequence */
289 memcpy(block
, asn1_sig
, sizeof(asn1_sig
));
290 memcpy(&block
[sizeof(asn1_sig
)], sha_dgst
, SHA1_SIZE
);
292 sig_size
= RSA_encrypt(rsa_ctx
, block
,
293 sizeof(asn1_sig
) + SHA1_SIZE
, enc_block
, 1);
295 buf
[(*offset
)++] = ASN1_BIT_STRING
;
296 set_gen_length(sig_size
+1, buf
, offset
);
297 buf
[(*offset
)++] = 0; /* bit string is multiple of 8 */
298 memcpy(&buf
[*offset
], enc_block
, sig_size
);
302 static int gen_tbs_cert(const char * dn
[],
303 const RSA_CTX
*rsa_ctx
, uint8_t *buf
, int *offset
,
309 int begin_tbs
= *offset
;
310 int seq_size
= pre_adjust_with_size(
311 ASN1_SEQUENCE
, &seq_offset
, buf
, offset
);
313 gen_serial_number(buf
, offset
);
314 gen_signature_alg(buf
, offset
);
316 /* CA certicate issuer */
317 if ((ret
= gen_issuer(dn
, buf
, offset
)))
320 gen_utc_time(buf
, offset
);
322 /* certificate issuer */
323 if ((ret
= gen_issuer(dn
, buf
, offset
)))
326 gen_pub_key(rsa_ctx
, buf
, offset
);
327 adjust_with_size(seq_size
, seq_offset
, buf
, offset
);
330 SHA1_Update(&sha_ctx
, &buf
[begin_tbs
], *offset
-begin_tbs
);
331 SHA1_Final(sha_dgst
, &sha_ctx
);
338 * Create a new certificate.
340 EXP_FUNC
int STDCALL
ssl_x509_create(SSL_CTX
*ssl_ctx
, uint32_t options
, const char * dn
[], uint8_t **cert_data
)
342 int ret
= X509_OK
, offset
= 0, seq_offset
;
343 /* allocate enough space to load a new certificate */
344 uint8_t *buf
= (uint8_t *)alloca(ssl_ctx
->rsa_ctx
->num_octets
*2 + 512);
345 uint8_t sha_dgst
[SHA1_SIZE
];
346 int seq_size
= pre_adjust_with_size(ASN1_SEQUENCE
,
347 &seq_offset
, buf
, &offset
);
349 if ((ret
= gen_tbs_cert(dn
, ssl_ctx
->rsa_ctx
, buf
, &offset
, sha_dgst
)) < 0)
352 gen_signature_alg(buf
, &offset
);
353 gen_signature(ssl_ctx
->rsa_ctx
, sha_dgst
, buf
, &offset
);
354 adjust_with_size(seq_size
, seq_offset
, buf
, &offset
);
355 *cert_data
= (uint8_t *)malloc(offset
); /* create the exact memory for it */
356 memcpy(*cert_data
, buf
, offset
);
359 return ret
< 0 ? ret
: offset
;