2 * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
11 # error "CT is disabled"
17 #include <openssl/err.h>
18 #include <openssl/obj_mac.h>
19 #include <openssl/x509.h>
23 SCT_CTX
*SCT_CTX_new(void)
25 SCT_CTX
*sctx
= OPENSSL_zalloc(sizeof(*sctx
));
28 CTerr(CT_F_SCT_CTX_NEW
, ERR_R_MALLOC_FAILURE
);
33 void SCT_CTX_free(SCT_CTX
*sctx
)
37 EVP_PKEY_free(sctx
->pkey
);
38 OPENSSL_free(sctx
->pkeyhash
);
39 OPENSSL_free(sctx
->ihash
);
40 OPENSSL_free(sctx
->certder
);
41 OPENSSL_free(sctx
->preder
);
46 * Finds the index of the first extension with the given NID in cert.
47 * If there is more than one extension with that NID, *is_duplicated is set to
48 * 1, otherwise 0 (unless it is NULL).
50 static int ct_x509_get_ext(X509
*cert
, int nid
, int *is_duplicated
)
52 int ret
= X509_get_ext_by_NID(cert
, nid
, -1);
54 if (is_duplicated
!= NULL
)
55 *is_duplicated
= ret
>= 0 && X509_get_ext_by_NID(cert
, nid
, ret
) >= 0;
61 * Modifies a certificate by deleting extensions and copying the issuer and
62 * AKID from the presigner certificate, if necessary.
63 * Returns 1 on success, 0 otherwise.
65 __owur
static int ct_x509_cert_fixup(X509
*cert
, X509
*presigner
)
68 int pre_akid_ext_is_dup
, cert_akid_ext_is_dup
;
70 if (presigner
== NULL
)
73 preidx
= ct_x509_get_ext(presigner
, NID_authority_key_identifier
,
74 &pre_akid_ext_is_dup
);
75 certidx
= ct_x509_get_ext(cert
, NID_authority_key_identifier
,
76 &cert_akid_ext_is_dup
);
78 /* An error occurred whilst searching for the extension */
79 if (preidx
< -1 || certidx
< -1)
81 /* Invalid certificate if they contain duplicate extensions */
82 if (pre_akid_ext_is_dup
|| cert_akid_ext_is_dup
)
84 /* AKID must be present in both certificate or absent in both */
85 if (preidx
>= 0 && certidx
== -1)
87 if (preidx
== -1 && certidx
>= 0)
89 /* Copy issuer name */
90 if (!X509_set_issuer_name(cert
, X509_get_issuer_name(presigner
)))
93 /* Retrieve and copy AKID encoding */
94 X509_EXTENSION
*preext
= X509_get_ext(presigner
, preidx
);
95 X509_EXTENSION
*certext
= X509_get_ext(cert
, certidx
);
96 ASN1_OCTET_STRING
*preextdata
;
98 /* Should never happen */
99 if (preext
== NULL
|| certext
== NULL
)
101 preextdata
= X509_EXTENSION_get_data(preext
);
102 if (preextdata
== NULL
||
103 !X509_EXTENSION_set_data(certext
, preextdata
))
109 int SCT_CTX_set1_cert(SCT_CTX
*sctx
, X509
*cert
, X509
*presigner
)
111 unsigned char *certder
= NULL
, *preder
= NULL
;
113 int certderlen
= 0, prederlen
= 0;
115 int poison_ext_is_dup
, sct_ext_is_dup
;
116 int poison_idx
= ct_x509_get_ext(cert
, NID_ct_precert_poison
, &poison_ext_is_dup
);
118 /* Duplicate poison extensions are present - error */
119 if (poison_ext_is_dup
)
122 /* If *cert doesn't have a poison extension, it isn't a precert */
123 if (poison_idx
== -1) {
124 /* cert isn't a precert, so we shouldn't have a presigner */
125 if (presigner
!= NULL
)
128 certderlen
= i2d_X509(cert
, &certder
);
133 /* See if cert has a precert SCTs extension */
134 idx
= ct_x509_get_ext(cert
, NID_ct_precert_scts
, &sct_ext_is_dup
);
135 /* Duplicate SCT extensions are present - error */
139 if (idx
>= 0 && poison_idx
>= 0) {
141 * cert can't both contain SCTs (i.e. have an SCT extension) and be a
142 * precert (i.e. have a poison extension).
152 * If either a poison or SCT extension is present, remove it before encoding
153 * cert. This, along with ct_x509_cert_fixup(), gets a TBSCertificate (see
154 * RFC5280) from cert, which is what the CT log signed when it produced the
160 /* Take a copy of certificate so we don't modify passed version */
161 pretmp
= X509_dup(cert
);
165 ext
= X509_delete_ext(pretmp
, idx
);
166 X509_EXTENSION_free(ext
);
168 if (!ct_x509_cert_fixup(pretmp
, presigner
))
171 prederlen
= i2d_re_X509_tbs(pretmp
, &preder
);
178 OPENSSL_free(sctx
->certder
);
179 sctx
->certder
= certder
;
180 sctx
->certderlen
= certderlen
;
182 OPENSSL_free(sctx
->preder
);
183 sctx
->preder
= preder
;
184 sctx
->prederlen
= prederlen
;
188 OPENSSL_free(certder
);
189 OPENSSL_free(preder
);
194 __owur
static int ct_public_key_hash(X509_PUBKEY
*pkey
, unsigned char **hash
,
198 unsigned char *md
= NULL
, *der
= NULL
;
202 /* Reuse buffer if possible */
203 if (*hash
!= NULL
&& *hash_len
>= SHA256_DIGEST_LENGTH
) {
206 md
= OPENSSL_malloc(SHA256_DIGEST_LENGTH
);
211 /* Calculate key hash */
212 der_len
= i2d_X509_PUBKEY(pkey
, &der
);
216 if (!EVP_Digest(der
, der_len
, md
, &md_len
, EVP_sha256(), NULL
))
222 *hash_len
= SHA256_DIGEST_LENGTH
;
233 int SCT_CTX_set1_issuer(SCT_CTX
*sctx
, const X509
*issuer
)
235 return SCT_CTX_set1_issuer_pubkey(sctx
, X509_get_X509_PUBKEY(issuer
));
238 int SCT_CTX_set1_issuer_pubkey(SCT_CTX
*sctx
, X509_PUBKEY
*pubkey
)
240 return ct_public_key_hash(pubkey
, &sctx
->ihash
, &sctx
->ihashlen
);
243 int SCT_CTX_set1_pubkey(SCT_CTX
*sctx
, X509_PUBKEY
*pubkey
)
245 EVP_PKEY
*pkey
= X509_PUBKEY_get(pubkey
);
250 if (!ct_public_key_hash(pubkey
, &sctx
->pkeyhash
, &sctx
->pkeyhashlen
)) {
255 EVP_PKEY_free(sctx
->pkey
);
260 void SCT_CTX_set_time(SCT_CTX
*sctx
, uint64_t time_in_ms
)
262 sctx
->epoch_time_in_ms
= time_in_ms
;