xref: /openbsd/usr.sbin/acme-client/key.c (revision 274d7c50)
1 /*	$Id: key.c,v 1.2 2019/06/17 15:41:59 florian Exp $ */
2 /*
3  * Copyright (c) 2019 Renaud Allard <renaud@allard.it>
4  * Copyright (c) 2016 Kristaps Dzonsons <kristaps@bsd.lv>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <err.h>
20 #include <stdlib.h>
21 #include <unistd.h>
22 
23 #include <openssl/evp.h>
24 #include <openssl/pem.h>
25 #include <openssl/rsa.h>
26 #include <openssl/ecdsa.h>
27 #include <openssl/ec.h>
28 #include <openssl/obj_mac.h>
29 
30 #include "key.h"
31 
32 /*
33  * Default number of bits when creating a new RSA key.
34  */
35 #define	KBITS 4096
36 #define ECCTYPE NID_secp384r1
37 
38 /*
39  * Create an RSA key with the default KBITS number of bits.
40  */
41 EVP_PKEY *
42 rsa_key_create(FILE *f, const char *fname)
43 {
44 	EVP_PKEY_CTX	*ctx = NULL;
45 	EVP_PKEY	*pkey = NULL;
46 
47 	/* First, create the context and the key. */
48 
49 	if ((ctx = EVP_PKEY_CTX_new_id(EVP_PKEY_RSA, NULL)) == NULL) {
50 		warnx("EVP_PKEY_CTX_new_id");
51 		goto err;
52 	} else if (EVP_PKEY_keygen_init(ctx) <= 0) {
53 		warnx("EVP_PKEY_keygen_init");
54 		goto err;
55 	} else if (EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, KBITS) <= 0) {
56 		warnx("EVP_PKEY_set_rsa_keygen_bits");
57 		goto err;
58 	} else if (EVP_PKEY_keygen(ctx, &pkey) <= 0) {
59 		warnx("EVP_PKEY_keygen");
60 		goto err;
61 	}
62 
63 	/* Serialise the key to the disc. */
64 
65 	if (PEM_write_PrivateKey(f, pkey, NULL, NULL, 0, NULL, NULL))
66 		goto out;
67 
68 	warnx("%s: PEM_write_PrivateKey", fname);
69 
70 err:
71 	EVP_PKEY_free(pkey);
72 	pkey = NULL;
73 out:
74 	EVP_PKEY_CTX_free(ctx);
75 	return pkey;
76 }
77 
78 EVP_PKEY *
79 ec_key_create(FILE *f, const char *fname)
80 {
81 	EC_KEY		*eckey = NULL;
82 	EVP_PKEY	*pkey = NULL;
83 
84 	if ((eckey = EC_KEY_new_by_curve_name(ECCTYPE)) == NULL ) {
85 		warnx("EC_KEY_new_by_curve_name");
86 		goto err;
87 	}
88 
89 	if (!EC_KEY_generate_key(eckey)) {
90 		warnx("EC_KEY_generate_key");
91 		goto err;
92 	}
93 
94 	/* set OPENSSL_EC_NAMED_CURVE to be able to load the key */
95 
96 	EC_KEY_set_asn1_flag(eckey, OPENSSL_EC_NAMED_CURVE);
97 
98 	/* Serialise the key to the disc in EC format */
99 
100 	if (!PEM_write_ECPrivateKey(f, eckey, NULL, NULL, 0, NULL, NULL)) {
101 		warnx("PEM_write_ECPrivateKey");
102 		goto err;
103 	}
104 
105 	/* Convert the EC key into a PKEY structure */
106 
107 	if ((pkey=EVP_PKEY_new()) == NULL) {
108 		warnx("EVP_PKEY_new");
109 		goto err;
110 	}
111 	if (!EVP_PKEY_set1_EC_KEY(pkey, eckey)) {
112 		warnx("EVP_PKEY_assign_EC_KEY");
113 		goto err;
114 	}
115 
116 	warnx("%s: PEM_write_ECPrivateKey", fname);
117 
118 	goto out;
119 
120 err:
121 	EC_KEY_free(eckey);
122 	EVP_PKEY_free(pkey);
123 	pkey = NULL;
124 out:
125 	return pkey;
126 }
127 
128 
129 
130 EVP_PKEY *
131 key_load(FILE *f, const char *fname)
132 {
133 	EVP_PKEY	*pkey;
134 
135 	pkey = PEM_read_PrivateKey(f, NULL, NULL, NULL);
136 	if (pkey == NULL) {
137 		warnx("%s: PEM_read_PrivateKey", fname);
138 		return NULL;
139 	} else if (EVP_PKEY_type(pkey->type) == EVP_PKEY_RSA ||
140 		   EVP_PKEY_type(pkey->type) == EVP_PKEY_EC )
141 		return pkey;
142 
143 	warnx("%s: unsupported key type", fname);
144 	EVP_PKEY_free(pkey);
145 	return NULL;
146 }
147