Implement internal abstraction for iostreams

fopencookie/funclose is a non-standard API and should not be used
in portable software. Additionally, the way FILE's fd is used in
non-blocking mode is undefined behaviour and cannot be relied on.

This introduces internal abstraction for io streams, that allows
implementing the desired virtualization of read/write operations
with necessary timeout handling.

ASTERISK-24515 #close
ASTERISK-24517 #close

Change-Id: Id916aef418b665ced6a7489aef74908b6e376e85

1 files changed, 91 insertions, 620 deletions

diff --git a/main/tcptls.c b/main/tcptls.c
index 262fca074..c8ebab434 100644
--- a/main/tcptls.c
+++ b/main/tcptls.c
@@ -47,506 +47,13 @@
 #include "asterisk/astobj2.h"
 #include "asterisk/pbx.h"
 
-/*! ao2 object used for the FILE stream fopencookie()/funopen() cookie. */
-struct ast_tcptls_stream {
-	/*! SSL state if not NULL */
-	SSL *ssl;
-	/*!
-	 * \brief Start time from when an I/O sequence must complete
-	 * by struct ast_tcptls_stream.timeout.
-	 *
-	 * \note If struct ast_tcptls_stream.start.tv_sec is zero then
-	 * start time is the current I/O request.
-	 */
-	struct timeval start;
-	/*!
-	 * \brief The socket returned by accept().
-	 *
-	 * \note Set to -1 if the stream is closed.
-	 */
-	int fd;
-	/*!
-	 * \brief Timeout in ms relative to struct ast_tcptls_stream.start
-	 * to wait for an event on struct ast_tcptls_stream.fd.
-	 *
-	 * \note Set to -1 to disable timeout.
-	 * \note The socket needs to be set to non-blocking for the timeout
-	 * feature to work correctly.
-	 */
-	int timeout;
-	/*! TRUE if stream can exclusively wait for fd input. */
-	int exclusive_input;
-};
-
-void ast_tcptls_stream_set_timeout_disable(struct ast_tcptls_stream *stream)
-{
-	ast_assert(stream != NULL);
-
-	stream->timeout = -1;
-}
-
-void ast_tcptls_stream_set_timeout_inactivity(struct ast_tcptls_stream *stream, int timeout)
-{
-	ast_assert(stream != NULL);
-
-	stream->start.tv_sec = 0;
-	stream->timeout = timeout;
-}
-
-void ast_tcptls_stream_set_timeout_sequence(struct ast_tcptls_stream *stream, struct timeval start, int timeout)
-{
-	ast_assert(stream != NULL);
-
-	stream->start = start;
-	stream->timeout = timeout;
-}
-
-void ast_tcptls_stream_set_exclusive_input(struct ast_tcptls_stream *stream, int exclusive_input)
-{
-	ast_assert(stream != NULL);
-
-	stream->exclusive_input = exclusive_input;
-}
-
-/*!
- * \internal
- * \brief fopencookie()/funopen() stream read function.
- *
- * \param cookie Stream control data.
- * \param buf Where to put read data.
- * \param size Size of the buffer.
- *
- * \retval number of bytes put into buf.
- * \retval 0 on end of file.
- * \retval -1 on error.
- */
-static HOOK_T tcptls_stream_read(void *cookie, char *buf, LEN_T size)
-{
-	struct ast_tcptls_stream *stream = cookie;
-	struct timeval start;
-	int ms;
-	int res;
-
-	if (!size) {
-		/* You asked for no data you got no data. */
-		return 0;
-	}
-
-	if (!stream || stream->fd == -1) {
-		errno = EBADF;
-		return -1;
-	}
-
-	if (stream->start.tv_sec) {
-		start = stream->start;
-	} else {
-		start = ast_tvnow();
-	}
-
-#if defined(DO_SSL)
-	if (stream->ssl) {
-		for (;;) {
-			res = SSL_read(stream->ssl, buf, size);
-			if (0 < res) {
-				/* We read some payload data. */
-				return res;
-			}
-			switch (SSL_get_error(stream->ssl, res)) {
-			case SSL_ERROR_ZERO_RETURN:
-				/* Report EOF for a shutdown */
-				ast_debug(1, "TLS clean shutdown alert reading data\n");
-				return 0;
-			case SSL_ERROR_WANT_READ:
-				if (!stream->exclusive_input) {
-					/* We cannot wait for data now. */
-					errno = EAGAIN;
-					return -1;
-				}
-				while ((ms = ast_remaining_ms(start, stream->timeout))) {
-					res = ast_wait_for_input(stream->fd, ms);
-					if (0 < res) {
-						/* Socket is ready to be read. */
-						break;
-					}
-					if (res < 0) {
-						if (errno == EINTR || errno == EAGAIN) {
-							/* Try again. */
-							continue;
-						}
-						ast_debug(1, "TLS socket error waiting for read data: %s\n",
-							strerror(errno));
-						return -1;
-					}
-				}
-				break;
-			case SSL_ERROR_WANT_WRITE:
-				while ((ms = ast_remaining_ms(start, stream->timeout))) {
-					res = ast_wait_for_output(stream->fd, ms);
-					if (0 < res) {
-						/* Socket is ready to be written. */
-						break;
-					}
-					if (res < 0) {
-						if (errno == EINTR || errno == EAGAIN) {
-							/* Try again. */
-							continue;
-						}
-						ast_debug(1, "TLS socket error waiting for write space: %s\n",
-							strerror(errno));
-						return -1;
-					}
-				}
-				break;
-			default:
-				/* Report EOF for an undecoded SSL or transport error. */
-				ast_debug(1, "TLS transport or SSL error reading data\n");
-				return 0;
-			}
-			if (!ms) {
-				/* Report EOF for a timeout */
-				ast_debug(1, "TLS timeout reading data\n");
-				return 0;
-			}
-		}
-	}
-#endif	/* defined(DO_SSL) */
-
-	for (;;) {
-		res = read(stream->fd, buf, size);
-		if (0 <= res || !stream->exclusive_input) {
-			/* Got data or we cannot wait for it. */
-			return res;
-		}
-		if (errno != EINTR && errno != EAGAIN) {
-			/* Not a retryable error. */
-			ast_debug(1, "TCP socket error reading data: %s\n",
-				strerror(errno));
-			return -1;
-		}
-		ms = ast_remaining_ms(start, stream->timeout);
-		if (!ms) {
-			/* Report EOF for a timeout */
-			ast_debug(1, "TCP timeout reading data\n");
-			return 0;
-		}
-		ast_wait_for_input(stream->fd, ms);
-	}
-}
-
-/*!
- * \internal
- * \brief fopencookie()/funopen() stream write function.
- *
- * \param cookie Stream control data.
- * \param buf Where to get data to write.
- * \param size Size of the buffer.
- *
- * \retval number of bytes written from buf.
- * \retval -1 on error.
- */
-static HOOK_T tcptls_stream_write(void *cookie, const char *buf, LEN_T size)
-{
-	struct ast_tcptls_stream *stream = cookie;
-	struct timeval start;
-	int ms;
-	int res;
-	int written;
-	int remaining;
-
-	if (!size) {
-		/* You asked to write no data you wrote no data. */
-		return 0;
-	}
-
-	if (!stream || stream->fd == -1) {
-		errno = EBADF;
-		return -1;
-	}
-
-	if (stream->start.tv_sec) {
-		start = stream->start;
-	} else {
-		start = ast_tvnow();
-	}
-
-#if defined(DO_SSL)
-	if (stream->ssl) {
-		written = 0;
-		remaining = size;
-		for (;;) {
-			res = SSL_write(stream->ssl, buf + written, remaining);
-			if (res == remaining) {
-				/* Everything was written. */
-				return size;
-			}
-			if (0 < res) {
-				/* Successfully wrote part of the buffer.  Try to write the rest. */
-				written += res;
-				remaining -= res;
-				continue;
-			}
-			switch (SSL_get_error(stream->ssl, res)) {
-			case SSL_ERROR_ZERO_RETURN:
-				ast_debug(1, "TLS clean shutdown alert writing data\n");
-				if (written) {
-					/* Report partial write. */
-					return written;
-				}
-				errno = EBADF;
-				return -1;
-			case SSL_ERROR_WANT_READ:
-				ms = ast_remaining_ms(start, stream->timeout);
-				if (!ms) {
-					/* Report partial write. */
-					ast_debug(1, "TLS timeout writing data (want read)\n");
-					return written;
-				}
-				ast_wait_for_input(stream->fd, ms);
-				break;
-			case SSL_ERROR_WANT_WRITE:
-				ms = ast_remaining_ms(start, stream->timeout);
-				if (!ms) {
-					/* Report partial write. */
-					ast_debug(1, "TLS timeout writing data (want write)\n");
-					return written;
-				}
-				ast_wait_for_output(stream->fd, ms);
-				break;
-			default:
-				/* Undecoded SSL or transport error. */
-				ast_debug(1, "TLS transport or SSL error writing data\n");
-				if (written) {
-					/* Report partial write. */
-					return written;
-				}
-				errno = EBADF;
-				return -1;
-			}
-		}
-	}
-#endif	/* defined(DO_SSL) */
-
-	written = 0;
-	remaining = size;
-	for (;;) {
-		res = write(stream->fd, buf + written, remaining);
-		if (res == remaining) {
-			/* Yay everything was written. */
-			return size;
-		}
-		if (0 < res) {
-			/* Successfully wrote part of the buffer.  Try to write the rest. */
-			written += res;
-			remaining -= res;
-			continue;
-		}
-		if (errno != EINTR && errno != EAGAIN) {
-			/* Not a retryable error. */
-			ast_debug(1, "TCP socket error writing: %s\n", strerror(errno));
-			if (written) {
-				return written;
-			}
-			return -1;
-		}
-		ms = ast_remaining_ms(start, stream->timeout);
-		if (!ms) {
-			/* Report partial write. */
-			ast_debug(1, "TCP timeout writing data\n");
-			return written;
-		}
-		ast_wait_for_output(stream->fd, ms);
-	}
-}
-
-/*!
- * \internal
- * \brief fopencookie()/funopen() stream close function.
- *
- * \param cookie Stream control data.
- *
- * \retval 0 on success.
- * \retval -1 on error.
- */
-static int tcptls_stream_close(void *cookie)
-{
-	struct ast_tcptls_stream *stream = cookie;
-
-	if (!stream) {
-		errno = EBADF;
-		return -1;
-	}
-
-	if (stream->fd != -1) {
-#if defined(DO_SSL)
-		if (stream->ssl) {
-			int res;
-
-			/*
-			 * According to the TLS standard, it is acceptable for an
-			 * application to only send its shutdown alert and then
-			 * close the underlying connection without waiting for
-			 * the peer's response (this way resources can be saved,
-			 * as the process can already terminate or serve another
-			 * connection).
-			 */
-			res = SSL_shutdown(stream->ssl);
-			if (res < 0) {
-				ast_log(LOG_ERROR, "SSL_shutdown() failed: %d\n",
-					SSL_get_error(stream->ssl, res));
-			}
-
-			if (!stream->ssl->server) {
-				/* For client threads, ensure that the error stack is cleared */
-#if OPENSSL_VERSION_NUMBER >= 0x10000000L
-				ERR_remove_thread_state(NULL);
-#else
-				ERR_remove_state(0);
-#endif	/* OPENSSL_VERSION_NUMBER >= 0x10000000L */
-			}
-
-			SSL_free(stream->ssl);
-			stream->ssl = NULL;
-		}
-#endif	/* defined(DO_SSL) */
-
-		/*
-		 * Issuing shutdown() is necessary here to avoid a race
-		 * condition where the last data written may not appear
-		 * in the TCP stream.  See ASTERISK-23548
-		 */
-		shutdown(stream->fd, SHUT_RDWR);
-		if (close(stream->fd)) {
-			ast_log(LOG_ERROR, "close() failed: %s\n", strerror(errno));
-		}
-		stream->fd = -1;
-	}
-	ao2_t_ref(stream, -1, "Closed tcptls stream cookie");
-
-	return 0;
-}
-
-/*!
- * \internal
- * \brief fopencookie()/funopen() stream destructor function.
- *
- * \param cookie Stream control data.
- *
- * \return Nothing
- */
-static void tcptls_stream_dtor(void *cookie)
-{
-#ifdef AST_DEVMODE
-	/* Since the ast_assert below is the only one using stream,
-	 * and ast_assert is only available with AST_DEVMODE, we
-	 * put this in a conditional to avoid compiler warnings. */
-	struct ast_tcptls_stream *stream = cookie;
-#endif
-
-	ast_assert(stream->fd == -1);
-}
-
-/*!
- * \internal
- * \brief fopencookie()/funopen() stream allocation function.
- *
- * \retval stream_cookie on success.
- * \retval NULL on error.
- */
-static struct ast_tcptls_stream *tcptls_stream_alloc(void)
-{
-	struct ast_tcptls_stream *stream;
-
-	stream = ao2_alloc_options(sizeof(*stream), tcptls_stream_dtor,
-		AO2_ALLOC_OPT_LOCK_NOLOCK);
-	if (stream) {
-		stream->fd = -1;
-		stream->timeout = -1;
-	}
-	return stream;
-}
-
-/*!
- * \internal
- * \brief Open a custom FILE stream for tcptls.
- *
- * \param stream Stream cookie control data.
- * \param ssl SSL state if not NULL.
- * \param fd Socket file descriptor.
- * \param timeout ms to wait for an event on fd. -1 if timeout disabled.
- *
- * \retval fp on success.
- * \retval NULL on error.
- */
-static FILE *tcptls_stream_fopen(struct ast_tcptls_stream *stream, SSL *ssl, int fd, int timeout)
-{
-	FILE *fp;
-
-#if defined(HAVE_FOPENCOOKIE)	/* the glibc/linux interface */
-	static const cookie_io_functions_t cookie_funcs = {
-		tcptls_stream_read,
-		tcptls_stream_write,
-		NULL,
-		tcptls_stream_close
-	};
-#endif	/* defined(HAVE_FOPENCOOKIE) */
-
-	if (fd == -1) {
-		/* Socket not open. */
-		return NULL;
-	}
-
-	stream->ssl = ssl;
-	stream->fd = fd;
-	stream->timeout = timeout;
-	ao2_t_ref(stream, +1, "Opening tcptls stream cookie");
-
-#if defined(HAVE_FUNOPEN)	/* the BSD interface */
-	fp = funopen(stream, tcptls_stream_read, tcptls_stream_write, NULL,
-		tcptls_stream_close);
-#elif defined(HAVE_FOPENCOOKIE)	/* the glibc/linux interface */
-	fp = fopencookie(stream, "w+", cookie_funcs);
-#else
-	/* could add other methods here */
-	ast_debug(2, "No stream FILE methods attempted!\n");
-	fp = NULL;
-#endif
-
-	if (!fp) {
-		stream->fd = -1;
-		ao2_t_ref(stream, -1, "Failed to open tcptls stream cookie");
-	}
-	return fp;
-}
-
-HOOK_T ast_tcptls_server_read(struct ast_tcptls_session_instance *tcptls_session, void *buf, size_t count)
-{
-	if (!tcptls_session->stream_cookie || tcptls_session->stream_cookie->fd == -1) {
-		ast_log(LOG_ERROR, "TCP/TLS read called on invalid stream.\n");
-		errno = EIO;
-		return -1;
-	}
-
-	return tcptls_stream_read(tcptls_session->stream_cookie, buf, count);
-}
-
-HOOK_T ast_tcptls_server_write(struct ast_tcptls_session_instance *tcptls_session, const void *buf, size_t count)
-{
-	if (!tcptls_session->stream_cookie || tcptls_session->stream_cookie->fd == -1) {
-		ast_log(LOG_ERROR, "TCP/TLS write called on invalid stream.\n");
-		errno = EIO;
-		return -1;
-	}
-
-	return tcptls_stream_write(tcptls_session->stream_cookie, buf, count);
-}
-
 static void session_instance_destructor(void *obj)
 {
 	struct ast_tcptls_session_instance *i = obj;
 
-	if (i->stream_cookie) {
-		ao2_t_ref(i->stream_cookie, -1, "Destroying tcptls session instance");
-		i->stream_cookie = NULL;
+	if (i->stream) {
+		ast_iostream_close(i->stream);
+		i->stream = NULL;
 	}
 	ast_free(i->overflow_buf);
 	ao2_cleanup(i->private_data);
@@ -591,9 +98,7 @@ static void *handle_tcptls_connection(void *data)
 {
 	struct ast_tcptls_session_instance *tcptls_session = data;
 #ifdef DO_SSL
-	int (*ssl_setup)(SSL *) = (tcptls_session->client) ? SSL_connect : SSL_accept;
-	int ret;
-	char err[256];
+	SSL *ssl;
 #endif
 
 	/* TCP/TLS connections are associated with external protocols, and
@@ -608,123 +113,94 @@ static void *handle_tcptls_connection(void *data)
 		return NULL;
 	}
 
-	tcptls_session->stream_cookie = tcptls_stream_alloc();
-	if (!tcptls_session->stream_cookie) {
-		ast_tcptls_close_session_file(tcptls_session);
-		ao2_ref(tcptls_session, -1);
-		return NULL;
-	}
+	if (tcptls_session->parent->tls_cfg) {
+#ifdef DO_SSL
+		if (ast_iostream_start_tls(&tcptls_session->stream, tcptls_session->parent->tls_cfg->ssl_ctx, tcptls_session->client) < 0) {
+			ast_tcptls_close_session_file(tcptls_session);
+			ao2_ref(tcptls_session, -1);
+			return NULL;
+		}
 
-	/*
-	* open a FILE * as appropriate.
-	*/
-	if (!tcptls_session->parent->tls_cfg) {
-		tcptls_session->f = tcptls_stream_fopen(tcptls_session->stream_cookie, NULL,
-			tcptls_session->fd, -1);
-		if (tcptls_session->f) {
-			if (setvbuf(tcptls_session->f, NULL, _IONBF, 0)) {
+		ssl = ast_iostream_get_ssl(tcptls_session->stream);
+		if ((tcptls_session->client && !ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_DONT_VERIFY_SERVER))
+			|| (!tcptls_session->client && ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_VERIFY_CLIENT))) {
+			X509 *peer;
+			long res;
+			peer = SSL_get_peer_certificate(ssl);
+			if (!peer) {
+				ast_log(LOG_ERROR, "No peer SSL certificate to verify\n");
 				ast_tcptls_close_session_file(tcptls_session);
+				ao2_ref(tcptls_session, -1);
+				return NULL;
 			}
-		}
-	}
-#ifdef DO_SSL
-	else if ( (tcptls_session->ssl = SSL_new(tcptls_session->parent->tls_cfg->ssl_ctx)) ) {
-		SSL_set_fd(tcptls_session->ssl, tcptls_session->fd);
-		if ((ret = ssl_setup(tcptls_session->ssl)) <= 0) {
-			ast_log(LOG_ERROR, "Problem setting up ssl connection: %s\n", ERR_error_string(ERR_get_error(), err));
-		} else if ((tcptls_session->f = tcptls_stream_fopen(tcptls_session->stream_cookie,
-			tcptls_session->ssl, tcptls_session->fd, -1))) {
-			if ((tcptls_session->client && !ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_DONT_VERIFY_SERVER))
-				|| (!tcptls_session->client && ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_VERIFY_CLIENT))) {
-				X509 *peer;
-				long res;
-				peer = SSL_get_peer_certificate(tcptls_session->ssl);
-				if (!peer) {
-					ast_log(LOG_ERROR, "No peer SSL certificate to verify\n");
-					ast_tcptls_close_session_file(tcptls_session);
-					ao2_ref(tcptls_session, -1);
-					return NULL;
-				}
 
-				res = SSL_get_verify_result(tcptls_session->ssl);
-				if (res != X509_V_OK) {
-					ast_log(LOG_ERROR, "Certificate did not verify: %s\n", X509_verify_cert_error_string(res));
-					X509_free(peer);
-					ast_tcptls_close_session_file(tcptls_session);
-					ao2_ref(tcptls_session, -1);
-					return NULL;
-				}
-				if (!ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_IGNORE_COMMON_NAME)) {
-					ASN1_STRING *str;
-					X509_NAME *name = X509_get_subject_name(peer);
-					STACK_OF(GENERAL_NAME) *alt_names;
-					int pos = -1;
-					int found = 0;
-
-					for (;;) {
-						/* Walk the certificate to check all available "Common Name" */
-						/* XXX Probably should do a gethostbyname on the hostname and compare that as well */
-						pos = X509_NAME_get_index_by_NID(name, NID_commonName, pos);
-						if (pos < 0) {
-							break;
-						}
-
-						str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, pos));
-						if (!check_tcptls_cert_name(str, tcptls_session->parent->hostname, "common name")) {
-							found = 1;
-							break;
-						}
+			res = SSL_get_verify_result(ssl);
+			if (res != X509_V_OK) {
+				ast_log(LOG_ERROR, "Certificate did not verify: %s\n", X509_verify_cert_error_string(res));
+				X509_free(peer);
+				ast_tcptls_close_session_file(tcptls_session);
+				ao2_ref(tcptls_session, -1);
+				return NULL;
+			}
+			if (!ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_IGNORE_COMMON_NAME)) {
+				ASN1_STRING *str;
+				X509_NAME *name = X509_get_subject_name(peer);
+				STACK_OF(GENERAL_NAME) *alt_names;
+				int pos = -1;
+				int found = 0;
+
+				for (;;) {
+					/* Walk the certificate to check all available "Common Name" */
+					/* XXX Probably should do a gethostbyname on the hostname and compare that as well */
+					pos = X509_NAME_get_index_by_NID(name, NID_commonName, pos);
+					if (pos < 0) {
+						break;
 					}
+					str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, pos));
+					if (!check_tcptls_cert_name(str, tcptls_session->parent->hostname, "common name")) {
+						found = 1;
+						break;
+					}
+				}
 
-					if (!found) {
-						alt_names = X509_get_ext_d2i(peer, NID_subject_alt_name, NULL, NULL);
-						if (alt_names != NULL) {
-							int alt_names_count = sk_GENERAL_NAME_num(alt_names);
-
-							for (pos = 0; pos < alt_names_count; pos++) {
-								const GENERAL_NAME *alt_name = sk_GENERAL_NAME_value(alt_names, pos);
+				if (!found) {
+					alt_names = X509_get_ext_d2i(peer, NID_subject_alt_name, NULL, NULL);
+					if (alt_names != NULL) {
+						int alt_names_count = sk_GENERAL_NAME_num(alt_names);
 
-								if (alt_name->type != GEN_DNS) {
-									continue;
-								}
+						for (pos = 0; pos < alt_names_count; pos++) {
+							const GENERAL_NAME *alt_name = sk_GENERAL_NAME_value(alt_names, pos);
 
-								if (!check_tcptls_cert_name(alt_name->d.dNSName, tcptls_session->parent->hostname, "alt name")) {
-									found = 1;
-									break;
-								}
+							if (alt_name->type != GEN_DNS) {
+								continue;
 							}
 
-							sk_GENERAL_NAME_pop_free(alt_names, GENERAL_NAME_free);
+							if (!check_tcptls_cert_name(alt_name->d.dNSName, tcptls_session->parent->hostname, "alt name")) {
+								found = 1;
+								break;
+							}
 						}
-					}
 
-					if (!found) {
-						ast_log(LOG_ERROR, "Certificate common name did not match (%s)\n", tcptls_session->parent->hostname);
-						X509_free(peer);
-						ast_tcptls_close_session_file(tcptls_session);
-						ao2_ref(tcptls_session, -1);
-						return NULL;
+						sk_GENERAL_NAME_pop_free(alt_names, GENERAL_NAME_free);
 					}
 				}
-				X509_free(peer);
+
+				if (!found) {
+					ast_log(LOG_ERROR, "Certificate common name did not match (%s)\n", tcptls_session->parent->hostname);
+					X509_free(peer);
+					ast_tcptls_close_session_file(tcptls_session);
+					ao2_ref(tcptls_session, -1);
+					return NULL;
+				}
 			}
+			X509_free(peer);
 		}
-		if (!tcptls_session->f) {	/* no success opening descriptor stacking */
-			SSL_free(tcptls_session->ssl);
-		}
-	}
-#endif /* DO_SSL */
-
-	if (!tcptls_session->f) {
+#else
+		ast_log(LOG_ERROR, "Attempted a TLS connection without OpenSSL support. This will not work!\n");
 		ast_tcptls_close_session_file(tcptls_session);
-		ast_log(LOG_WARNING, "FILE * open failed!\n");
-#ifndef DO_SSL
-		if (tcptls_session->parent->tls_cfg) {
-			ast_log(LOG_ERROR, "Attempted a TLS connection without OpenSSL support. This will not work!\n");
-		}
-#endif
 		ao2_ref(tcptls_session, -1);
 		return NULL;
+#endif /* DO_SSL */
 	}
 
 	if (tcptls_session->parent->worker_fn) {
@@ -772,7 +248,13 @@ void *ast_tcptls_server_root(void *data)
 		tcptls_session->overflow_buf = ast_str_create(128);
 		flags = fcntl(fd, F_GETFL);
 		fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
-		tcptls_session->fd = fd;
+
+		tcptls_session->stream = ast_iostream_from_fd(&fd);
+		if (!tcptls_session->stream) {
+			ast_log(LOG_WARNING, "No memory for new session iostream\n");
+			continue;
+		}
+
 		tcptls_session->parent = desc;
 		ast_sockaddr_copy(&tcptls_session->remote_address, &addr);
 
@@ -1036,7 +518,7 @@ client_start_error:
 
 struct ast_tcptls_session_instance *ast_tcptls_client_create(struct ast_tcptls_session_args *desc)
 {
-	int x = 1;
+	int fd, x = 1;
 	struct ast_tcptls_session_instance *tcptls_session = NULL;
 
 	/* Do nothing if nothing has changed */
@@ -1052,8 +534,8 @@ struct ast_tcptls_session_instance *ast_tcptls_client_create(struct ast_tcptls_s
 		close(desc->accept_fd);
 	}
 
-	desc->accept_fd = socket(ast_sockaddr_is_ipv6(&desc->remote_address) ?
-				 AF_INET6 : AF_INET, SOCK_STREAM, IPPROTO_TCP);
+	fd = desc->accept_fd = socket(ast_sockaddr_is_ipv6(&desc->remote_address) ?
+				      AF_INET6 : AF_INET, SOCK_STREAM, IPPROTO_TCP);
 	if (desc->accept_fd < 0) {
 		ast_log(LOG_ERROR, "Unable to allocate socket for %s: %s\n",
 			desc->name, strerror(errno));
@@ -1079,7 +561,11 @@ struct ast_tcptls_session_instance *ast_tcptls_client_create(struct ast_tcptls_s
 
 	tcptls_session->overflow_buf = ast_str_create(128);
 	tcptls_session->client = 1;
-	tcptls_session->fd = desc->accept_fd;
+	tcptls_session->stream = ast_iostream_from_fd(&fd);
+	if (!tcptls_session->stream) {
+		goto error;
+	}
+
 	tcptls_session->parent = desc;
 	tcptls_session->parent->worker_fn = NULL;
 	ast_sockaddr_copy(&tcptls_session->remote_address,
@@ -1170,24 +656,9 @@ error:
 
 void ast_tcptls_close_session_file(struct ast_tcptls_session_instance *tcptls_session)
 {
-	if (tcptls_session->f) {
-		fflush(tcptls_session->f);
-		if (fclose(tcptls_session->f)) {
-			ast_log(LOG_ERROR, "fclose() failed: %s\n", strerror(errno));
-		}
-		tcptls_session->f = NULL;
-		tcptls_session->fd = -1;
-	} else if (tcptls_session->fd != -1) {
-		/*
-		 * Issuing shutdown() is necessary here to avoid a race
-		 * condition where the last data written may not appear
-		 * in the TCP stream.  See ASTERISK-23548
-		 */
-		shutdown(tcptls_session->fd, SHUT_RDWR);
-		if (close(tcptls_session->fd)) {
-			ast_log(LOG_ERROR, "close() failed: %s\n", strerror(errno));
-		}
-		tcptls_session->fd = -1;
+	if (tcptls_session->stream) {
+		ast_iostream_close(tcptls_session->stream);
+		tcptls_session->stream = NULL;
 	} else {
 		ast_log(LOG_ERROR, "ast_tcptls_close_session_file invoked on session instance without file or file descriptor\n");
 	}