Add support for certificate_authorities extension in ClientHello

doc/dox_comments/header_files/ssl.h

@@ -15257,6 +15257,239 @@ RFC 9146 and RFC 9147.
 const unsigned char* wolfSSL_dtls_cid_parse(const unsigned char* msg,
         unsigned int msgSz, unsigned int cidSz);
 
+/*!
+    \ingroup TLS
+    \brief On the server, this sets a list of CA names to be sent to clients in
+    certificate requests as a hint for which CA's are supported by the server.
+
+    On the client, this function has no effect.
+
+    \param [in] ctx Pointer to the wolfSSL context
+    \param [in] names List of names to be set
+
+    \sa wolfSSL_set_client_CA_list
+    \sa wolfSSL_CTX_get_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_CTX_set0_CA_list
+    \sa wolfSSL_set0_CA_list
+    \sa wolfSSL_CTX_get0_CA_list
+    \sa wolfSSL_get0_CA_list
+    \sa wolfSSL_get0_peer_CA_list
+*/
+void wolfSSL_CTX_set_client_CA_list(WOLFSSL_CTX* ctx,
+                                    WOLF_STACK_OF(WOLFSSL_X509_NAME)* names);
+
+/*!
+    \ingroup TLS
+    \brief This retrieves the list previously set via
+     wolfSSL_CTX_set_client_CA_list, or NULL if no list has been set.
+
+    \param [in] ctx Pointer to the wolfSSL context
+    \return A stack of WOLFSSL_X509_NAMEs containing the CA names
+
+    \sa wolfSSL_set_client_CA_list
+    \sa wolfSSL_CTX_set_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_CTX_set0_CA_list
+    \sa wolfSSL_set0_CA_list
+    \sa wolfSSL_CTX_get0_CA_list
+    \sa wolfSSL_get0_CA_list
+    \sa wolfSSL_get0_peer_CA_list
+*/
+WOLFSSL_STACK *wolfSSL_CTX_get_client_CA_list(
+        const WOLFSSL_CTX *ctx);
+
+/*!
+    \ingroup TLS
+    \brief Same as wolfSSL_CTX_set_client_CA_list, but specific to a session.
+    If a CA list is set on both the context and the session, the list on the
+    session is used.
+
+    \param [in] ssl Pointer to the WOLFSSL object
+    \param [in] names List of names to be set.
+
+    \sa wolfSSL_CTX_set_client_CA_list
+    \sa wolfSSL_CTX_get_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_CTX_set0_CA_list
+    \sa wolfSSL_set0_CA_list
+    \sa wolfSSL_CTX_get0_CA_list
+    \sa wolfSSL_get0_CA_list
+    \sa wolfSSL_get0_peer_CA_list
+*/
+void wolfSSL_set_client_CA_list(WOLFSSL* ssl,
+                                    WOLF_STACK_OF(WOLFSSL_X509_NAME)* names);
+
+/*!
+    \ingroup TLS
+    \brief On the server, this retrieves the list previously set via
+    wolfSSL_set_client_CA_list. If none was set, returns the list previously
+    set via wolfSSL_CTX_set_client_CA_list. If no list at all was set, returns
+    NULL.
+
+    On the client, this retrieves the list that was received from the server,
+    or NULL if none was received. wolfSSL_CTX_set_cert_cb can be used to
+    register a callback to dynamically load certificates when a certificate
+    request is received from the server.
+
+    \param [in] ssl Pointer to the WOLFSSL object
+    \return A stack of WOLFSSL_X509_NAMEs containing the CA names
+
+    \sa wolfSSL_CTX_set_cert_cb
+    \sa wolfSSL_CTX_set_client_CA_list
+    \sa wolfSSL_CTX_get_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_CTX_set0_CA_list
+    \sa wolfSSL_set0_CA_list
+    \sa wolfSSL_CTX_get0_CA_list
+    \sa wolfSSL_get0_CA_list
+    \sa wolfSSL_get0_peer_CA_list
+*/
+WOLFSSL_STACK* wolfSSL_get_client_CA_list(
+            const WOLFSSL* ssl);
+
+/*!
+    \ingroup TLS
+    \brief This function sets a list of CA names to be sent to the peer as a
+    hint for which CA's are supported for its authentication.
+
+    In TLS >= 1.3, this is supported in both directions between the client and
+    the server. On the server, the CA names will be sent as part of a
+    CertificateRequest, making this function an equivalent of *_set_client_CA_list;
+    on the client, these are sent as part of ClientHello.
+
+    In TLS < 1.3, sending CA names from the client to the server is not
+    supported, therefore this function is equivalent to
+    wolfSSL_CTX_set_client_CA_list.
+
+    Note that the lists set via *_set_client_CA_list and *_set0_CA_list are
+    separate internally, i.e. calling *_get_client_CA_list will not retrieve a
+    list set via *_set0_CA_list and vice versa. If both are set, the server will
+    ignore *_set0_CA_list when sending CA names to the client.
+
+    \param [in] ctx Pointer to the wolfSSL context
+    \param [in] names List of names to be set
+
+    \sa wolfSSL_CTX_set_client_CA_list
+    \sa wolfSSL_set_client_CA_list
+    \sa wolfSSL_CTX_get_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_set0_CA_list
+    \sa wolfSSL_CTX_get0_CA_list
+    \sa wolfSSL_get0_CA_list
+    \sa wolfSSL_get0_peer_CA_list
+*/
+void wolfSSL_CTX_set0_CA_list(WOLFSSL_CTX *ctx,
+        WOLF_STACK_OF(WOLFSSL_X509_NAME)* names);
+
+/*!
+    \ingroup TLS
+    \brief This retrieves the list previously set via
+    wolfSSL_CTX_set0_CA_list, or NULL if no list has been set.
+
+    \param [in] ctx Pointer to the wolfSSL context
+    \return A stack of WOLFSSL_X509_NAMEs containing the CA names
+
+    \sa wolfSSL_CTX_set_client_CA_list
+    \sa wolfSSL_set_client_CA_list
+    \sa wolfSSL_CTX_get_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_CTX_set0_CA_list
+    \sa wolfSSL_set0_CA_list
+    \sa wolfSSL_get0_CA_list
+    \sa wolfSSL_get0_peer_CA_list
+*/
+WOLFSSL_STACK *wolfSSL_CTX_get0_CA_list(
+        const WOLFSSL_CTX *ctx);
+
+/*!
+    \ingroup TLS
+    \brief Same as wolfSSL_CTX_set0_CA_list, but specific to a session.
+    If a CA list is set on both the context and the session, the list on the
+    session is used.
+
+    \param [in] ssl Pointer to the WOLFSSL object
+    \param [in] names List of names to be set.
+
+    \sa wolfSSL_CTX_set_client_CA_list
+    \sa wolfSSL_set_client_CA_list
+    \sa wolfSSL_CTX_get_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_CTX_set0_CA_list
+    \sa wolfSSL_CTX_get0_CA_list
+    \sa wolfSSL_get0_CA_list
+    \sa wolfSSL_get0_peer_CA_list
+*/
+void wolfSSL_set0_CA_list(WOLFSSL *ssl,
+        WOLF_STACK_OF(WOLFSSL_X509_NAME) *names);
+
+/*!
+    \ingroup TLS
+    \brief This retrieves the list previously set via wolfSSL_set0_CA_list. If
+    none was set, returns the list previously set via
+    wolfSSL_CTX_set0_CA_list. If no list at all was set, returns NULL.
+
+    \param [in] ssl Pointer to the WOLFSSL object
+    \return A stack of WOLFSSL_X509_NAMEs containing the CA names
+
+    \sa wolfSSL_CTX_set_client_CA_list
+    \sa wolfSSL_set_client_CA_list
+    \sa wolfSSL_CTX_get_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_CTX_set0_CA_list
+    \sa wolfSSL_set0_CA_list
+    \sa wolfSSL_CTX_get0_CA_list
+    \sa wolfSSL_get0_peer_CA_list
+*/
+WOLFSSL_STACK *wolfSSL_get0_CA_list(
+        const WOLFSSL *ssl);
+
+/*!
+    \ingroup TLS
+    \brief This returns the CA list received from the peer.
+
+    On the client, this is the list sent by the server in a CertificateRequest,
+    and this function is equivalent to wolfSSL_get_client_CA_list.
+
+    On the server, this is the list sent by the client in the ClientHello message
+    in TLS >= 1.3; in TLS < 1.3, the function always returns NULL on the server
+    side.
+
+    wolfSSL_CTX_set_cert_cb can be used to register a callback to dynamically
+    load certificates when a CA list is received from the peer.
+
+    \param [in] ssl Pointer to the WOLFSSL object
+    \return A stack of WOLFSSL_X509_NAMEs containing the CA names
+
+    \sa wolfSSL_CTX_set_cert_cb
+    \sa wolfSSL_CTX_set_client_CA_list
+    \sa wolfSSL_set_client_CA_list
+    \sa wolfSSL_CTX_get_client_CA_list
+    \sa wolfSSL_get_client_CA_list
+    \sa wolfSSL_CTX_set0_CA_list
+    \sa wolfSSL_set0_CA_list
+    \sa wolfSSL_CTX_get0_CA_list
+    \sa wolfSSL_get0_CA_list
+*/
+WOLFSSL_STACK *wolfSSL_get0_peer_CA_list(const WOLFSSL *ssl);
+
+/*!
+    \ingroup TLS
+    \brief This function sets a callback that will be called whenever a
+    certificate is about to be used, to allow the application to inspect, set
+    or clear any certificates, for example to react to a CA list sent from the
+    peer.
+
+    \param [in] ctx Pointer to the wolfSSL context
+    \param [in] cb Function pointer to the callback
+    \param [in] arg Pointer that will be passed to the callback
+
+    \sa wolfSSL_get0_peer_CA_list
+    \sa wolfSSL_get_client_CA_list
+*/
+void wolfSSL_CTX_set_cert_cb(WOLFSSL_CTX* ctx,
+    int (*cb)(WOLFSSL *, void *), void *arg);
+
 /*!
     \ingroup TLS
 

src/internal.c

@@ -2877,6 +2877,8 @@ void SSL_CtxResourceFree(WOLFSSL_CTX* ctx)
     #ifndef WOLFSSL_NO_CA_NAMES
         wolfSSL_sk_X509_NAME_pop_free(ctx->client_ca_names, NULL);
         ctx->client_ca_names = NULL;
+        wolfSSL_sk_X509_NAME_pop_free(ctx->ca_names, NULL);
+        ctx->ca_names = NULL;
     #endif
     #ifdef OPENSSL_EXTRA
         if (ctx->x509Chain) {
@@ -6667,9 +6669,11 @@ int InitSSL_Suites(WOLFSSL* ssl)
     byte haveAnon = 0;
     byte haveRSA = 0;
     byte haveMcast = 0;
+    byte haveCertSetupCb = 0;
 
     (void)haveAnon; /* Squash unused var warnings */
     (void)haveMcast;
+    (void)haveCertSetupCb;
 
     if (!ssl)
         return BAD_FUNC_ARG;
@@ -6688,6 +6692,10 @@ int InitSSL_Suites(WOLFSSL* ssl)
     haveMcast = (byte)ssl->options.haveMcast;
 #endif /* WOLFSSL_MULTICAST */
 #endif /* !NO_CERTS && !WOLFSSL_SESSION_EXPORT */
+#if defined(WOLFSSL_TLS13) && !defined(NO_CERTS) && defined(OPENSSL_EXTRA)
+    if (ssl->ctx->certSetupCb != NULL)
+        haveCertSetupCb = 1;
+#endif /* WOLFSSL_TLS13 && !NO_CERTS && OPENSSL_EXTRA */
 
 #ifdef WOLFSSL_EARLY_DATA
     if (ssl->options.side == WOLFSSL_SERVER_END)
@@ -6715,10 +6723,11 @@ int InitSSL_Suites(WOLFSSL* ssl)
     }
 
 #if !defined(NO_CERTS) && !defined(WOLFSSL_SESSION_EXPORT)
-    /* make sure server has cert and key unless using PSK, Anon, or
-     * Multicast. This should be true even if just switching ssl ctx */
+    /* make sure server has cert and key unless using PSK, Anon,
+     * Multicast or cert setup callback. This should be true even if just
+     * switching ssl ctx */
     if (ssl->options.side == WOLFSSL_SERVER_END &&
-            !havePSK && !haveAnon && !haveMcast) {
+            !havePSK && !haveAnon && !haveMcast && !haveCertSetupCb) {
 
         /* server certificate must be loaded */
         if (!ssl->buffers.certificate || !ssl->buffers.certificate->buffer) {
@@ -8789,6 +8798,10 @@ void wolfSSL_ResourceFree(WOLFSSL* ssl)
 #ifndef WOLFSSL_NO_CA_NAMES
     wolfSSL_sk_X509_NAME_pop_free(ssl->client_ca_names, NULL);
     ssl->client_ca_names = NULL;
+    wolfSSL_sk_X509_NAME_pop_free(ssl->ca_names, NULL);
+    ssl->ca_names = NULL;
+    wolfSSL_sk_X509_NAME_pop_free(ssl->peer_ca_names, NULL);
+    ssl->peer_ca_names = NULL;
 #endif
 #ifdef WOLFSSL_DTLS13
     Dtls13FreeFsmResources(ssl);
@@ -24823,7 +24836,7 @@ int SendCertificateRequest(WOLFSSL* ssl)
 
 #ifndef WOLFSSL_NO_CA_NAMES
     /* Certificate Authorities */
-    names = SSL_CA_NAMES(ssl);
+    names = SSL_PRIORITY_CA_NAMES(ssl);
     while (names != NULL) {
         byte seq[MAX_SEQ_SZ];
         WOLFSSL_X509_NAME* name = names->data.name;
@@ -24915,7 +24928,7 @@ int SendCertificateRequest(WOLFSSL* ssl)
     c16toa((word16)dnLen, &output[i]);  /* auth's */
     i += REQ_HEADER_SZ;
 #ifndef WOLFSSL_NO_CA_NAMES
-    names = SSL_CA_NAMES(ssl);
+    names = SSL_PRIORITY_CA_NAMES(ssl);
     while (names != NULL) {
         byte seq[MAX_SEQ_SZ];
         WOLFSSL_X509_NAME* name = names->data.name;
@@ -31745,10 +31758,9 @@ static int HashSkeData(WOLFSSL* ssl, enum wc_HashType hashType,
             return BUFFER_ERROR;
 
     #if defined(OPENSSL_ALL) || defined(WOLFSSL_NGINX) || defined(HAVE_LIGHTY)
-        if (ssl->client_ca_names != ssl->ctx->client_ca_names)
-            wolfSSL_sk_X509_NAME_pop_free(ssl->client_ca_names, NULL);
-        ssl->client_ca_names = wolfSSL_sk_X509_NAME_new(NULL);
-        if (ssl->client_ca_names == NULL) {
+        wolfSSL_sk_X509_NAME_pop_free(ssl->peer_ca_names, NULL);
+        ssl->peer_ca_names = wolfSSL_sk_X509_NAME_new(NULL);
+        if (ssl->peer_ca_names == NULL) {
             return MEMORY_ERROR;
         }
     #endif
@@ -31793,7 +31805,7 @@ static int HashSkeData(WOLFSSL* ssl, enum wc_HashType hashType,
                 }
 
                 if (ret == 0) {
-                    if (wolfSSL_sk_X509_NAME_push(ssl->client_ca_names, name)
+                    if (wolfSSL_sk_X509_NAME_push(ssl->peer_ca_names, name)
                         <= 0)
                     {
                         ret = MEMORY_ERROR;