/*
- * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
* Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
* Copyright 2005 Nokia. All rights reserved.
*
*/
#include <stdio.h>
-#include "ssl_locl.h"
+#include "ssl_local.h"
#include "e_os.h"
#include <openssl/objects.h>
#include <openssl/x509v3.h>
#include "internal/refcount.h"
#include "internal/ktls.h"
+DEFINE_STACK_OF(X509)
+DEFINE_STACK_OF(X509_NAME)
+DEFINE_STACK_OF_CONST(SSL_CIPHER)
+DEFINE_STACK_OF(X509_EXTENSION)
+DEFINE_STACK_OF(OCSP_RESPID)
+DEFINE_STACK_OF(SRTP_PROTECTION_PROFILE)
+DEFINE_STACK_OF(SCT)
+
static int ssl_undefined_function_1(SSL *ssl, SSL3_RECORD *r, size_t s, int t)
{
(void)r;
/* Clear the verification result peername */
X509_VERIFY_PARAM_move_peername(s->param, NULL);
+ /* Clear any shared connection state */
+ OPENSSL_free(s->shared_sigalgs);
+ s->shared_sigalgs = NULL;
+ s->shared_sigalgslen = 0;
+
/*
* Check to see if we were changed into a different method, if so, revert
* back.
ctx->method = meth;
- if (!SSL_CTX_set_ciphersuites(ctx, TLS_DEFAULT_CIPHERSUITES)) {
+ if (!SSL_CTX_set_ciphersuites(ctx, OSSL_default_ciphersuites())) {
SSLerr(SSL_F_SSL_CTX_SET_SSL_VERSION, SSL_R_SSL_LIBRARY_HAS_NO_CIPHERS);
return 0;
}
ctx->tls13_ciphersuites,
&(ctx->cipher_list),
&(ctx->cipher_list_by_id),
- SSL_DEFAULT_CIPHER_LIST, ctx->cert);
+ OSSL_default_cipher_list(), ctx->cert);
if ((sk == NULL) || (sk_SSL_CIPHER_num(sk) <= 0)) {
SSLerr(SSL_F_SSL_CTX_SET_SSL_VERSION, SSL_R_SSL_LIBRARY_HAS_NO_CIPHERS);
return 0;
s->ext.ecpointformats_len =
ctx->ext.ecpointformats_len;
}
+#endif
if (ctx->ext.supportedgroups) {
s->ext.supportedgroups =
OPENSSL_memdup(ctx->ext.supportedgroups,
goto err;
s->ext.supportedgroups_len = ctx->ext.supportedgroups_len;
}
-#endif
+
#ifndef OPENSSL_NO_NEXTPROTONEG
s->ext.npn = NULL;
#endif
int SSL_CTX_set_session_id_context(SSL_CTX *ctx, const unsigned char *sid_ctx,
unsigned int sid_ctx_len)
{
- if (sid_ctx_len > sizeof(ctx->sid_ctx)) {
+ if (sid_ctx_len > SSL_MAX_SID_CTX_LENGTH) {
SSLerr(SSL_F_SSL_CTX_SET_SESSION_ID_CONTEXT,
SSL_R_SSL_SESSION_ID_CONTEXT_TOO_LONG);
return 0;
sk_SSL_CIPHER_free(s->cipher_list);
sk_SSL_CIPHER_free(s->cipher_list_by_id);
sk_SSL_CIPHER_free(s->tls13_ciphersuites);
+ sk_SSL_CIPHER_free(s->peer_ciphers);
/* Make the next call work :-) */
if (s->session != NULL) {
clear_ciphers(s);
ssl_cert_free(s->cert);
+ OPENSSL_free(s->shared_sigalgs);
/* Free up if allocated */
OPENSSL_free(s->ext.hostname);
SSL_CTX_free(s->session_ctx);
#ifndef OPENSSL_NO_EC
OPENSSL_free(s->ext.ecpointformats);
- OPENSSL_free(s->ext.supportedgroups);
+ OPENSSL_free(s->ext.peer_ecpointformats);
#endif /* OPENSSL_NO_EC */
+ OPENSSL_free(s->ext.supportedgroups);
+ OPENSSL_free(s->ext.peer_supportedgroups);
sk_X509_EXTENSION_pop_free(s->ext.ocsp.exts, X509_EXTENSION_free);
#ifndef OPENSSL_NO_OCSP
sk_OCSP_RESPID_pop_free(s->ext.ocsp.ids, OCSP_RESPID_free);
return -1;
}
-#ifndef OPENSSL_NO_KTLS
- ret = ktls_sendfile(SSL_get_wfd(s), fd, offset, size, flags);
+#ifdef OPENSSL_NO_KTLS
+ ERR_raise_data(ERR_LIB_SYS, ERR_R_INTERNAL_ERROR, "calling sendfile()");
+ return -1;
#else
- ret = -1;
-#endif
+ ret = ktls_sendfile(SSL_get_wfd(s), fd, offset, size, flags);
if (ret < 0) {
#if defined(EAGAIN) && defined(EINTR) && defined(EBUSY)
if ((get_last_sys_error() == EAGAIN) ||
BIO_set_retry_write(s->wbio);
else
#endif
-#ifdef OPENSSL_NO_KTLS
- SYSerr(SYS_F_SENDFILE, get_last_sys_error());
-#else
SSLerr(SSL_F_SSL_SENDFILE, SSL_R_UNINITIALIZED);
-#endif
return ret;
}
s->rwstate = SSL_NOTHING;
return ret;
+#endif
}
int SSL_write(SSL *s, const void *buf, int num)
return (s->renegotiate != 0);
}
+int SSL_new_session_ticket(SSL *s)
+{
+ if (SSL_in_init(s) || SSL_IS_FIRST_HANDSHAKE(s) || !s->server
+ || !SSL_IS_TLS13(s))
+ return 0;
+ s->ext.extra_tickets_expected++;
+ return 1;
+}
+
long SSL_ctrl(SSL *s, int cmd, long larg, void *parg)
{
long l;
STACK_OF(SSL_CIPHER) *SSL_get_client_ciphers(const SSL *s)
{
- if ((s == NULL) || (s->session == NULL) || !s->server)
+ if ((s == NULL) || !s->server)
return NULL;
- return s->session->ciphers;
+ return s->peer_ciphers;
}
STACK_OF(SSL_CIPHER) *SSL_get1_supported_ciphers(SSL *s)
int i;
if (!s->server
- || s->session == NULL
- || s->session->ciphers == NULL
+ || s->peer_ciphers == NULL
|| size < 2)
return NULL;
p = buf;
- clntsk = s->session->ciphers;
+ clntsk = s->peer_ciphers;
srvrsk = SSL_get_ciphers(s);
if (clntsk == NULL || srvrsk == NULL)
return NULL;
return buf;
}
-/** return a servername extension value if provided in Client Hello, or NULL.
- * So far, only host_name types are defined (RFC 3546).
+/**
+ * Return the requested servername (SNI) value. Note that the behaviour varies
+ * depending on:
+ * - whether this is called by the client or the server,
+ * - if we are before or during/after the handshake,
+ * - if a resumption or normal handshake is being attempted/has occurred
+ * - whether we have negotiated TLSv1.2 (or below) or TLSv1.3
+ *
+ * Note that only the host_name type is defined (RFC 3546).
*/
-
const char *SSL_get_servername(const SSL *s, const int type)
{
+ /*
+ * If we don't know if we are the client or the server yet then we assume
+ * client.
+ */
+ int server = s->handshake_func == NULL ? 0 : s->server;
if (type != TLSEXT_NAMETYPE_host_name)
return NULL;
- /*
- * SNI is not negotiated in pre-TLS-1.3 resumption flows, so fake up an
- * SNI value to return if we are resuming/resumed. N.B. that we still
- * call the relevant callbacks for such resumption flows, and callbacks
- * might error out if there is not a SNI value available.
- */
- if (s->hit)
- return s->session->ext.hostname;
+ if (server) {
+ /**
+ * Server side
+ * In TLSv1.3 on the server SNI is not associated with the session
+ * but in TLSv1.2 or below it is.
+ *
+ * Before the handshake:
+ * - return NULL
+ *
+ * During/after the handshake (TLSv1.2 or below resumption occurred):
+ * - If a servername was accepted by the server in the original
+ * handshake then it will return that servername, or NULL otherwise.
+ *
+ * During/after the handshake (TLSv1.2 or below resumption did not occur):
+ * - The function will return the servername requested by the client in
+ * this handshake or NULL if none was requested.
+ */
+ if (s->hit && !SSL_IS_TLS13(s))
+ return s->session->ext.hostname;
+ } else {
+ /**
+ * Client side
+ *
+ * Before the handshake:
+ * - If a servername has been set via a call to
+ * SSL_set_tlsext_host_name() then it will return that servername
+ * - If one has not been set, but a TLSv1.2 resumption is being
+ * attempted and the session from the original handshake had a
+ * servername accepted by the server then it will return that
+ * servername
+ * - Otherwise it returns NULL
+ *
+ * During/after the handshake (TLSv1.2 or below resumption occurred):
+ * - If the session from the orignal handshake had a servername accepted
+ * by the server then it will return that servername.
+ * - Otherwise it returns the servername set via
+ * SSL_set_tlsext_host_name() (or NULL if it was not called).
+ *
+ * During/after the handshake (TLSv1.2 or below resumption did not occur):
+ * - It will return the servername set via SSL_set_tlsext_host_name()
+ * (or NULL if it was not called).
+ */
+ if (SSL_in_before(s)) {
+ if (s->ext.hostname == NULL
+ && s->session != NULL
+ && s->session->ssl_version != TLS1_3_VERSION)
+ return s->session->ext.hostname;
+ } else {
+ if (!SSL_IS_TLS13(s) && s->hit && s->session->ext.hostname != NULL)
+ return s->session->ext.hostname;
+ }
+ }
+
return s->ext.hostname;
}
int SSL_get_servername_type(const SSL *s)
{
- if (s->session
- && (!s->ext.hostname ? s->session->
- ext.hostname : s->ext.hostname))
+ if (SSL_get_servername(s, TLSEXT_NAMETYPE_host_name) != NULL)
return TLSEXT_NAMETYPE_host_name;
return -1;
}
unsigned *len)
{
*data = s->ext.npn;
- if (!*data) {
+ if (*data == NULL) {
*len = 0;
} else {
*len = (unsigned int)s->ext.npn_len;
* via ssl.h.
*/
-SSL_CTX *SSL_CTX_new(const SSL_METHOD *meth)
+SSL_CTX *SSL_CTX_new_with_libctx(OPENSSL_CTX *libctx, const char *propq,
+ const SSL_METHOD *meth)
{
SSL_CTX *ret = NULL;
if (meth == NULL) {
- SSLerr(SSL_F_SSL_CTX_NEW, SSL_R_NULL_SSL_METHOD_PASSED);
+ SSLerr(0, SSL_R_NULL_SSL_METHOD_PASSED);
return NULL;
}
return NULL;
if (SSL_get_ex_data_X509_STORE_CTX_idx() < 0) {
- SSLerr(SSL_F_SSL_CTX_NEW, SSL_R_X509_VERIFICATION_SETUP_PROBLEMS);
+ SSLerr(0, SSL_R_X509_VERIFICATION_SETUP_PROBLEMS);
goto err;
}
ret = OPENSSL_zalloc(sizeof(*ret));
if (ret == NULL)
goto err;
+ ret->libctx = libctx;
+ if (propq != NULL) {
+ ret->propq = OPENSSL_strdup(propq);
+ if (ret->propq == NULL)
+ goto err;
+ }
+
ret->method = meth;
ret->min_proto_version = 0;
ret->max_proto_version = 0;
ret->references = 1;
ret->lock = CRYPTO_THREAD_lock_new();
if (ret->lock == NULL) {
- SSLerr(SSL_F_SSL_CTX_NEW, ERR_R_MALLOC_FAILURE);
+ SSLerr(0, ERR_R_MALLOC_FAILURE);
OPENSSL_free(ret);
return NULL;
}
if (ret->cert_store == NULL)
goto err;
#ifndef OPENSSL_NO_CT
- ret->ctlog_store = CTLOG_STORE_new();
+ ret->ctlog_store = CTLOG_STORE_new_with_libctx(libctx, propq);
if (ret->ctlog_store == NULL)
goto err;
#endif
- if (!SSL_CTX_set_ciphersuites(ret, TLS_DEFAULT_CIPHERSUITES))
+ /* initialize cipher/digest methods table */
+ if (!ssl_load_ciphers(ret))
+ goto err2;
+ /* initialise sig algs */
+ if (!ssl_setup_sig_algs(ret))
+ goto err2;
+
+
+ if (!SSL_CTX_set_ciphersuites(ret, OSSL_default_ciphersuites()))
goto err;
if (!ssl_create_cipher_list(ret->method,
ret->tls13_ciphersuites,
&ret->cipher_list, &ret->cipher_list_by_id,
- SSL_DEFAULT_CIPHER_LIST, ret->cert)
+ OSSL_default_cipher_list(), ret->cert)
|| sk_SSL_CIPHER_num(ret->cipher_list) <= 0) {
- SSLerr(SSL_F_SSL_CTX_NEW, SSL_R_LIBRARY_HAS_NO_CIPHERS);
+ SSLerr(0, SSL_R_LIBRARY_HAS_NO_CIPHERS);
goto err2;
}
if (ret->param == NULL)
goto err;
- if ((ret->md5 = EVP_get_digestbyname("ssl3-md5")) == NULL) {
- SSLerr(SSL_F_SSL_CTX_NEW, SSL_R_UNABLE_TO_LOAD_SSL3_MD5_ROUTINES);
- goto err2;
- }
- if ((ret->sha1 = EVP_get_digestbyname("ssl3-sha1")) == NULL) {
- SSLerr(SSL_F_SSL_CTX_NEW, SSL_R_UNABLE_TO_LOAD_SSL3_SHA1_ROUTINES);
- goto err2;
- }
+ /*
+ * If these aren't available from the provider we'll get NULL returns.
+ * That's fine but will cause errors later if SSLv3 is negotiated
+ */
+ ret->md5 = ssl_evp_md_fetch(libctx, NID_md5, propq);
+ ret->sha1 = ssl_evp_md_fetch(libctx, NID_sha1, propq);
if ((ret->ca_names = sk_X509_NAME_new_null()) == NULL)
goto err;
ret->split_send_fragment = SSL3_RT_MAX_PLAIN_LENGTH;
/* Setup RFC5077 ticket keys */
- if ((RAND_bytes(ret->ext.tick_key_name,
- sizeof(ret->ext.tick_key_name)) <= 0)
- || (RAND_priv_bytes(ret->ext.secure->tick_hmac_key,
- sizeof(ret->ext.secure->tick_hmac_key)) <= 0)
- || (RAND_priv_bytes(ret->ext.secure->tick_aes_key,
- sizeof(ret->ext.secure->tick_aes_key)) <= 0))
+ if ((RAND_bytes_ex(libctx, ret->ext.tick_key_name,
+ sizeof(ret->ext.tick_key_name)) <= 0)
+ || (RAND_priv_bytes_ex(libctx, ret->ext.secure->tick_hmac_key,
+ sizeof(ret->ext.secure->tick_hmac_key)) <= 0)
+ || (RAND_priv_bytes_ex(libctx, ret->ext.secure->tick_aes_key,
+ sizeof(ret->ext.secure->tick_aes_key)) <= 0))
ret->options |= SSL_OP_NO_TICKET;
- if (RAND_priv_bytes(ret->ext.cookie_hmac_key,
- sizeof(ret->ext.cookie_hmac_key)) <= 0)
+ if (RAND_priv_bytes_ex(libctx, ret->ext.cookie_hmac_key,
+ sizeof(ret->ext.cookie_hmac_key)) <= 0)
goto err;
#ifndef OPENSSL_NO_SRP
return ret;
err:
- SSLerr(SSL_F_SSL_CTX_NEW, ERR_R_MALLOC_FAILURE);
+ SSLerr(0, ERR_R_MALLOC_FAILURE);
err2:
SSL_CTX_free(ret);
return NULL;
}
+SSL_CTX *SSL_CTX_new(const SSL_METHOD *meth)
+{
+ return SSL_CTX_new_with_libctx(NULL, NULL, meth);
+}
+
int SSL_CTX_up_ref(SSL_CTX *ctx)
{
int i;
#ifndef OPENSSL_NO_EC
OPENSSL_free(a->ext.ecpointformats);
- OPENSSL_free(a->ext.supportedgroups);
#endif
+ OPENSSL_free(a->ext.supportedgroups);
OPENSSL_free(a->ext.alpn);
OPENSSL_secure_free(a->ext.secure);
+ ssl_evp_md_free(a->md5);
+ ssl_evp_md_free(a->sha1);
+
+ for (i = 0; i < SSL_ENC_NUM_IDX; i++)
+ ssl_evp_cipher_free(a->ssl_cipher_methods[i]);
+ for (i = 0; i < SSL_MD_NUM_IDX; i++)
+ ssl_evp_md_free(a->ssl_digest_methods[i]);
+
+ OPENSSL_free(a->sigalg_lookup_cache);
+
CRYPTO_THREAD_lock_free(a->lock);
+ OPENSSL_free(a->propq);
+
OPENSSL_free(a);
}
#ifndef OPENSSL_NO_GOST
if (ssl_has_cert(s, SSL_PKEY_GOST12_512)) {
- mask_k |= SSL_kGOST;
+ mask_k |= SSL_kGOST | SSL_kGOST18;
mask_a |= SSL_aGOST12;
}
if (ssl_has_cert(s, SSL_PKEY_GOST12_256)) {
- mask_k |= SSL_kGOST;
+ mask_k |= SSL_kGOST | SSL_kGOST18;
mask_a |= SSL_aGOST12;
}
if (ssl_has_cert(s, SSL_PKEY_GOST01)) {
lookup = X509_STORE_add_lookup(ctx->cert_store, X509_LOOKUP_hash_dir());
if (lookup == NULL)
return 0;
+
+ /* We ignore errors, in case the directory doesn't exist */
+ ERR_set_mark();
+
X509_LOOKUP_add_dir(lookup, NULL, X509_FILETYPE_DEFAULT);
- /* Clear any errors if the default directory does not exist */
- ERR_clear_error();
+ ERR_pop_to_mark();
return 1;
}
if (lookup == NULL)
return 0;
+ /* We ignore errors, in case the directory doesn't exist */
+ ERR_set_mark();
+
X509_LOOKUP_load_file(lookup, NULL, X509_FILETYPE_DEFAULT);
- /* Clear any errors if the default file does not exist */
- ERR_clear_error();
+ ERR_pop_to_mark();
return 1;
}
+int SSL_CTX_set_default_verify_store(SSL_CTX *ctx)
+{
+ X509_LOOKUP *lookup;
+
+ lookup = X509_STORE_add_lookup(ctx->cert_store, X509_LOOKUP_store());
+ if (lookup == NULL)
+ return 0;
+
+ /* We ignore errors, in case the directory doesn't exist */
+ ERR_set_mark();
+
+ X509_LOOKUP_add_store(lookup, NULL);
+
+ ERR_pop_to_mark();
+
+ return 1;
+}
+
+int SSL_CTX_load_verify_file(SSL_CTX *ctx, const char *CAfile)
+{
+ return X509_STORE_load_file(ctx->cert_store, CAfile);
+}
+
+int SSL_CTX_load_verify_dir(SSL_CTX *ctx, const char *CApath)
+{
+ return X509_STORE_load_path(ctx->cert_store, CApath);
+}
+
+int SSL_CTX_load_verify_store(SSL_CTX *ctx, const char *CAstore)
+{
+ return X509_STORE_load_store(ctx->cert_store, CAstore);
+}
+
int SSL_CTX_load_verify_locations(SSL_CTX *ctx, const char *CAfile,
const char *CApath)
{
- return X509_STORE_load_locations(ctx->cert_store, CAfile, CApath);
+ if (CAfile == NULL && CApath == NULL)
+ return 0;
+ if (CAfile != NULL && !SSL_CTX_load_verify_file(ctx, CAfile))
+ return 0;
+ if (CApath != NULL && !SSL_CTX_load_verify_dir(ctx, CApath))
+ return 0;
+ return 1;
}
void SSL_set_info_callback(SSL *ssl,
return 1;
}
-void SSL_set_record_padding_callback(SSL *ssl,
+int SSL_set_record_padding_callback(SSL *ssl,
size_t (*cb) (SSL *ssl, int type,
size_t len, void *arg))
{
- ssl->record_padding_cb = cb;
+ BIO *b;
+
+ b = SSL_get_wbio(ssl);
+ if (b == NULL || !BIO_get_ktls_send(b)) {
+ ssl->record_padding_cb = cb;
+ return 1;
+ }
+ return 0;
}
void SSL_set_record_padding_callback_arg(SSL *ssl, void *arg)
return ret;
}
-int SSL_session_reused(SSL *s)
+int SSL_session_reused(const SSL *s)
{
return s->hit;
}
return s->server;
}
-#if !OPENSSL_API_1_1_0
+#ifndef OPENSSL_NO_DEPRECATED_1_1_0
void SSL_set_debug(SSL *s, int debug)
{
/* Old function was do-nothing anyway... */
}
}
- ctx = CT_POLICY_EVAL_CTX_new();
+ ctx = CT_POLICY_EVAL_CTX_new_with_libctx(s->ctx->libctx, s->ctx->propq);
if (ctx == NULL) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_SSL_VALIDATE_CT,
ERR_R_MALLOC_FAILURE);
s->allow_early_data_cb = cb;
s->allow_early_data_cb_data = arg;
}
+
+const EVP_CIPHER *ssl_evp_cipher_fetch(OPENSSL_CTX *libctx,
+ int nid,
+ const char *properties)
+{
+ EVP_CIPHER *ciph;
+
+#ifndef OPENSSL_NO_ENGINE
+ ENGINE *eng;
+
+ /*
+ * If there is an Engine available for this cipher we use the "implicit"
+ * form to ensure we use that engine later.
+ */
+ eng = ENGINE_get_cipher_engine(nid);
+ if (eng != NULL) {
+ ENGINE_finish(eng);
+ return EVP_get_cipherbynid(nid);
+ }
+#endif
+
+ /* Otherwise we do an explicit fetch. This may fail and that could be ok */
+ ERR_set_mark();
+ ciph = EVP_CIPHER_fetch(libctx, OBJ_nid2sn(nid), properties);
+ ERR_pop_to_mark();
+ return ciph;
+}
+
+
+int ssl_evp_cipher_up_ref(const EVP_CIPHER *cipher)
+{
+ /* Don't up-ref an implicit EVP_CIPHER */
+ if (EVP_CIPHER_provider(cipher) == NULL)
+ return 1;
+
+ /*
+ * The cipher was explicitly fetched and therefore it is safe to cast
+ * away the const
+ */
+ return EVP_CIPHER_up_ref((EVP_CIPHER *)cipher);
+}
+
+void ssl_evp_cipher_free(const EVP_CIPHER *cipher)
+{
+ if (cipher == NULL)
+ return;
+
+ if (EVP_CIPHER_provider(cipher) != NULL) {
+ /*
+ * The cipher was explicitly fetched and therefore it is safe to cast
+ * away the const
+ */
+ EVP_CIPHER_free((EVP_CIPHER *)cipher);
+ }
+}
+
+const EVP_MD *ssl_evp_md_fetch(OPENSSL_CTX *libctx,
+ int nid,
+ const char *properties)
+{
+ EVP_MD *md;
+
+#ifndef OPENSSL_NO_ENGINE
+ ENGINE *eng;
+
+ /*
+ * If there is an Engine available for this digest we use the "implicit"
+ * form to ensure we use that engine later.
+ */
+ eng = ENGINE_get_digest_engine(nid);
+ if (eng != NULL) {
+ ENGINE_finish(eng);
+ return EVP_get_digestbynid(nid);
+ }
+#endif
+
+ /* Otherwise we do an explicit fetch */
+ ERR_set_mark();
+ md = EVP_MD_fetch(libctx, OBJ_nid2sn(nid), properties);
+ ERR_pop_to_mark();
+ return md;
+}
+
+int ssl_evp_md_up_ref(const EVP_MD *md)
+{
+ /* Don't up-ref an implicit EVP_MD */
+ if (EVP_MD_provider(md) == NULL)
+ return 1;
+
+ /*
+ * The digest was explicitly fetched and therefore it is safe to cast
+ * away the const
+ */
+ return EVP_MD_up_ref((EVP_MD *)md);
+}
+
+void ssl_evp_md_free(const EVP_MD *md)
+{
+ if (md == NULL)
+ return;
+
+ if (EVP_MD_provider(md) != NULL) {
+ /*
+ * The digest was explicitly fetched and therefore it is safe to cast
+ * away the const
+ */
+ EVP_MD_free((EVP_MD *)md);
+ }
+}