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/* $OpenBSD: ct_local.h,v 1.8 2021/12/20 17:19:19 jsing Exp $ */
/*
* Written by Rob Percival (robpercival@google.com) for the OpenSSL project.
*/
/* ====================================================================
* Copyright (c) 2016 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* licensing@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*/
#include <stddef.h>
#include <openssl/ct.h>
#include <openssl/evp.h>
#include <openssl/safestack.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include "bytestring.h"
/* Number of bytes in an SCT v1 LogID - see RFC 6962 section 3.2. */
#define CT_V1_LOG_ID_LEN 32
/* Maximum size of an SCT - see RFC 6962 section 3.3. */
#define MAX_SCT_SIZE 65535
#define MAX_SCT_LIST_SIZE MAX_SCT_SIZE
/*
* Macros to write integers in network-byte order.
*/
#define s2n(s,c) ((c[0]=(unsigned char)(((s)>> 8)&0xff), \
c[1]=(unsigned char)(((s) )&0xff)),c+=2)
#define l2n3(l,c) ((c[0]=(unsigned char)(((l)>>16)&0xff), \
c[1]=(unsigned char)(((l)>> 8)&0xff), \
c[2]=(unsigned char)(((l) )&0xff)),c+=3)
#define l2n8(l,c) (*((c)++)=(unsigned char)(((l)>>56)&0xff), \
*((c)++)=(unsigned char)(((l)>>48)&0xff), \
*((c)++)=(unsigned char)(((l)>>40)&0xff), \
*((c)++)=(unsigned char)(((l)>>32)&0xff), \
*((c)++)=(unsigned char)(((l)>>24)&0xff), \
*((c)++)=(unsigned char)(((l)>>16)&0xff), \
*((c)++)=(unsigned char)(((l)>> 8)&0xff), \
*((c)++)=(unsigned char)(((l) )&0xff))
/* Signed Certificate Timestamp */
struct sct_st {
sct_version_t version;
/* If version is not SCT_VERSION_V1, this contains the encoded SCT */
unsigned char *sct;
size_t sct_len;
/*
* If version is SCT_VERSION_V1, fields below contain components of
* the SCT
*/
unsigned char *log_id;
size_t log_id_len;
/*
* Note, we cannot distinguish between an unset timestamp, and one
* that is set to 0. However since CT didn't exist in 1970, no real
* SCT should ever be set as such.
*/
uint64_t timestamp;
unsigned char *ext;
size_t ext_len;
unsigned char hash_alg;
unsigned char sig_alg;
unsigned char *sig;
size_t sig_len;
/* Log entry type */
ct_log_entry_type_t entry_type;
/* Where this SCT was found, e.g. certificate, OCSP response, etc. */
sct_source_t source;
/* The result of the last attempt to validate this SCT. */
sct_validation_status_t validation_status;
};
/* Miscellaneous data that is useful when verifying an SCT */
struct sct_ctx_st {
/* Public key */
EVP_PKEY *pkey;
/* Hash of public key */
unsigned char *pkeyhash;
size_t pkeyhashlen;
/* For pre-certificate: issuer public key hash */
unsigned char *ihash;
size_t ihashlen;
/* certificate encoding */
unsigned char *certder;
size_t certderlen;
/* pre-certificate encoding */
unsigned char *preder;
size_t prederlen;
/*
* milliseconds since epoch (to check that the SCT isn't from the
* future)
*/
uint64_t epoch_time_in_ms;
};
/* Context when evaluating whether a Certificate Transparency policy is met */
struct ct_policy_eval_ctx_st {
X509 *cert;
X509 *issuer;
CTLOG_STORE *log_store;
/*
* milliseconds since epoch (to check that the SCT isn't from the
* future)
*/
uint64_t epoch_time_in_ms;
};
/*
* Creates a new context for verifying an SCT.
*/
SCT_CTX *SCT_CTX_new(void);
/*
* Deletes an SCT verification context.
*/
void SCT_CTX_free(SCT_CTX *sctx);
/*
* Sets the certificate that the SCT was created for.
* If *cert does not have a poison extension, presigner must be NULL.
* If *cert does not have a poison extension, it may have a single SCT
* (NID_ct_precert_scts) extension.
* If either *cert or *presigner have an AKID (NID_authority_key_identifier)
* extension, both must have one.
* Returns 1 on success, 0 on failure.
*/
int SCT_CTX_set1_cert(SCT_CTX *sctx, X509 *cert, X509 *presigner);
/*
* Sets the issuer of the certificate that the SCT was created for.
* This is just a convenience method to save extracting the public key and
* calling SCT_CTX_set1_issuer_pubkey().
* Issuer must not be NULL.
* Returns 1 on success, 0 on failure.
*/
int SCT_CTX_set1_issuer(SCT_CTX *sctx, const X509 *issuer);
/*
* Sets the public key of the issuer of the certificate that the SCT was created
* for.
* The public key must not be NULL.
* Returns 1 on success, 0 on failure.
*/
int SCT_CTX_set1_issuer_pubkey(SCT_CTX *sctx, X509_PUBKEY *pubkey);
/*
* Sets the public key of the CT log that the SCT is from.
* Returns 1 on success, 0 on failure.
*/
int SCT_CTX_set1_pubkey(SCT_CTX *sctx, X509_PUBKEY *pubkey);
/*
* Sets the time to evaluate the SCT against, in milliseconds since the Unix
* epoch. If the SCT's timestamp is after this time, it will be interpreted as
* having been issued in the future. RFC6962 states that "TLS clients MUST
* reject SCTs whose timestamp is in the future", so an SCT will not validate
* in this case.
*/
void SCT_CTX_set_time(SCT_CTX *sctx, uint64_t time_in_ms);
/*
* Verifies an SCT with the given context.
* Returns 1 if the SCT verifies successfully; any other value indicates
* failure. See EVP_DigestVerifyFinal() for the meaning of those values.
*/
int SCT_CTX_verify(const SCT_CTX *sctx, const SCT *sct);
/*
* Does this SCT have the minimum fields populated to be usable?
* Returns 1 if so, 0 otherwise.
*/
int SCT_is_complete(const SCT *sct);
/*
* Does this SCT have the signature-related fields populated?
* Returns 1 if so, 0 otherwise.
* This checks that the signature and hash algorithms are set to supported
* values and that the signature field is set.
*/
int SCT_signature_is_complete(const SCT *sct);
/*
* TODO(RJPercival): Create an SCT_signature struct and make i2o_SCT_signature
* and o2i_SCT_signature conform to the i2d/d2i conventions.
*/
/*
* Serialize (to TLS format) an |sct| signature and write it to |out|.
* If |out| is null, no signature will be output but the length will be returned.
* If |out| points to a null pointer, a string will be allocated to hold the
* TLS-format signature. It is the responsibility of the caller to free it.
* If |out| points to an allocated string, the signature will be written to it.
* The length of the signature in TLS format will be returned.
*/
int i2o_SCT_signature(const SCT *sct, unsigned char **out);
/*
* Parses an SCT signature in TLS format and populates the |sct| with it.
* |in| should be a pointer to a string containing the TLS-format signature.
* |in| will be advanced to the end of the signature if parsing succeeds.
* |len| should be the length of the signature in |in|.
* Returns the number of bytes parsed, or a negative integer if an error occurs.
* If an error occurs, the SCT's signature NID may be updated whilst the
* signature field itself remains unset.
*/
int o2i_SCT_signature(SCT *sct, CBS *cbs);
/*
* Handlers for Certificate Transparency X509v3/OCSP extensions
*/
extern const X509V3_EXT_METHOD v3_ct_scts[3];
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