1/*
2 * Copyright (c) 2018 Thomas Pornin <pornin@bolet.org>
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sublicense, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
24
25#include "inner.h"
26
27/* see bearssl_x509.h */
28size_t
29br_encode_rsa_raw_der(void *dest, const br_rsa_private_key *sk,
30	const br_rsa_public_key *pk, const void *d, size_t dlen)
31{
32	/*
33	 * ASN.1 format:
34	 *
35	 *   RSAPrivateKey ::= SEQUENCE {
36	 *       version           Version,
37	 *       modulus           INTEGER,  -- n
38	 *       publicExponent    INTEGER,  -- e
39	 *       privateExponent   INTEGER,  -- d
40	 *       prime1            INTEGER,  -- p
41	 *       prime2            INTEGER,  -- q
42	 *       exponent1         INTEGER,  -- d mod (p-1)
43	 *       exponent2         INTEGER,  -- d mod (q-1)
44	 *       coefficient       INTEGER,  -- (inverse of q) mod p
45	 *       otherPrimeInfos   OtherPrimeInfos OPTIONAL
46	 *   }
47	 *
48	 * The 'version' field is an INTEGER of value 0 (meaning: there
49	 * are exactly two prime factors), and 'otherPrimeInfos' will
50	 * be absent (because there are exactly two prime factors).
51	 */
52
53	br_asn1_uint num[9];
54	size_t u, slen;
55
56	/*
57	 * For all INTEGER values, get the pointer and length for the
58	 * data bytes.
59	 */
60	num[0] = br_asn1_uint_prepare(NULL, 0);
61	num[1] = br_asn1_uint_prepare(pk->n, pk->nlen);
62	num[2] = br_asn1_uint_prepare(pk->e, pk->elen);
63	num[3] = br_asn1_uint_prepare(d, dlen);
64	num[4] = br_asn1_uint_prepare(sk->p, sk->plen);
65	num[5] = br_asn1_uint_prepare(sk->q, sk->qlen);
66	num[6] = br_asn1_uint_prepare(sk->dp, sk->dplen);
67	num[7] = br_asn1_uint_prepare(sk->dq, sk->dqlen);
68	num[8] = br_asn1_uint_prepare(sk->iq, sk->iqlen);
69
70	/*
71	 * Get the length of the SEQUENCE contents.
72	 */
73	slen = 0;
74	for (u = 0; u < 9; u ++) {
75		uint32_t ilen;
76
77		ilen = num[u].asn1len;
78		slen += 1 + len_of_len(ilen) + ilen;
79	}
80
81	if (dest == NULL) {
82		return 1 + len_of_len(slen) + slen;
83	} else {
84		unsigned char *buf;
85		size_t lenlen;
86
87		buf = dest;
88		*buf ++ = 0x30;  /* SEQUENCE tag */
89		lenlen = br_asn1_encode_length(buf, slen);
90		buf += lenlen;
91		for (u = 0; u < 9; u ++) {
92			buf += br_asn1_encode_uint(buf, num[u]);
93		}
94		return 1 + lenlen + slen;
95	}
96}
97