fixes #201 TLS configuration should support files for certificates and keys

This adds support for configuration of TLS websockets using the files
for keys, certificates, and CRLs.  Significant changes to the websocket,
TLS, and HTTP layers were made here.  We now expect TLS configuration to
be tied to the HTTP layer, and the HTTP code creates default configuration
objects based on the URL supplied.  (HTTP dialers and listeners are now
created with a URL rather than a sockaddr, giving them access to the scheme
as well.)

We fixed several bugs affecting TLS validation, and added a test suite
that confirms that validation works as it should.  We also fixed an orphaned
socket during HTTP negotiation, responsible for an occasional assertion
error if the http handshake does not complete successfully.  Finally several
use-after-free races were closed.

TLS layer changes include reporting of handshake failures using newly
created "standard" error codes for peer authentication and cryptographic
failures.

The use of the '*' wild card in URLs at bind time is no longer supported
for websocket at least.

Documentation updates for all this are in place as well.

1 files changed, 103 insertions, 12 deletions

diff --git a/src/supplemental/http/client.c b/src/supplemental/http/client.c
index b1794f93..7542043d 100644
--- a/src/supplemental/http/client.c
+++ b/src/supplemental/http/client.c
@@ -1,6 +1,6 @@
 //
-// Copyright 2017 Staysail Systems, Inc. <info@staysail.tech>
-// Copyright 2017 Capitar IT Group BV <info@capitar.com>
+// Copyright 2018 Staysail Systems, Inc. <info@staysail.tech>
+// Copyright 2018 Capitar IT Group BV <info@capitar.com>
 //
 // This software is supplied under the terms of the MIT License, a
 // copy of which should be located in the distribution where this
@@ -19,12 +19,12 @@
 #include "http.h"
 
 struct nni_http_client {
-	nng_sockaddr     addr;
 	nni_list         aios;
 	nni_mtx          mtx;
 	bool             closed;
 	nng_tls_config * tls;
 	nni_aio *        connaio;
+	nni_url *        url;
 	nni_plat_tcp_ep *tep;
 };
 
@@ -92,26 +92,98 @@ nni_http_client_fini(nni_http_client *c)
 		nni_tls_config_fini(c->tls);
 	}
 #endif
+	if (c->url != NULL) {
+		nni_url_free(c->url);
+	}
 	NNI_FREE_STRUCT(c);
 }
 
 int
-nni_http_client_init(nni_http_client **cp, nng_sockaddr *sa)
+nni_http_client_init(nni_http_client **cp, const char *urlstr)
 {
-	int rv;
-
+	int              rv;
+	nni_url *        url;
 	nni_http_client *c;
-	if ((c = NNI_ALLOC_STRUCT(c)) == NULL) {
-		return (NNG_ENOMEM);
+	nni_aio *        aio;
+	nni_sockaddr     sa;
+	char *           host;
+	char *           port;
+
+	if ((rv = nni_url_parse(&url, urlstr)) != 0) {
+		return (rv);
+	}
+
+	if (strlen(url->u_hostname) == 0) {
+		// We require a valid hostname.
+		nni_url_free(url);
+		return (NNG_EADDRINVAL);
+	}
+	if ((strcmp(url->u_scheme, "http") != 0) &&
+#ifdef NNG_SUPP_TLS
+	    (strcmp(url->u_scheme, "https") != 0) &&
+	    (strcmp(url->u_scheme, "wss") != 0) &&
+#endif
+	    (strcmp(url->u_scheme, "ws") != 0)) {
+		return (NNG_EADDRINVAL);
 	}
-	c->addr = *sa;
-	rv = nni_plat_tcp_ep_init(&c->tep, NULL, &c->addr, NNI_EP_MODE_DIAL);
+
+	// For now we are looking up the address.  We would really like
+	// to do this later, but we need TcP support for this.  One
+	// imagines the ability to create a tcp dialer that does the
+	// necessary DNS lookups, etc. all asynchronously.
+	if ((rv = nni_aio_init(&aio, NULL, NULL)) != 0) {
+		nni_url_free(url);
+		return (rv);
+	}
+	aio->a_addr = &sa;
+	host        = (strlen(url->u_hostname) != 0) ? url->u_hostname : NULL;
+	port        = (strlen(url->u_port) != 0) ? url->u_port : NULL;
+	nni_plat_tcp_resolv(host, port, NNG_AF_UNSPEC, false, aio);
+	nni_aio_wait(aio);
+	rv = nni_aio_result(aio);
+	nni_aio_fini(aio);
 	if (rv != 0) {
-		NNI_FREE_STRUCT(c);
+		nni_url_free(url);
 		return (rv);
 	}
+
+	if ((c = NNI_ALLOC_STRUCT(c)) == NULL) {
+		return (NNG_ENOMEM);
+	}
 	nni_mtx_init(&c->mtx);
 	nni_aio_list_init(&c->aios);
+	c->url = url;
+
+#ifdef NNG_SUPP_TLS
+	if ((strcmp(url->u_scheme, "https") == 0) ||
+	    (strcmp(url->u_scheme, "wss") == 0)) {
+		rv = nni_tls_config_init(&c->tls, NNG_TLS_MODE_CLIENT);
+		if (rv != 0) {
+			nni_http_client_fini(c);
+			return (rv);
+		}
+		// Take the server name right from the client URL. We only
+		// consider the name, as the port is never part of the
+		// certificate.
+		rv = nng_tls_config_server_name(c->tls, url->u_hostname);
+		if (rv != 0) {
+			nni_http_client_fini(c);
+			return (rv);
+		}
+
+		// Note that the application has to supply the location of
+		// certificates.  We could probably use a default based
+		// on environment or common locations used by OpenSSL, but
+		// as there is no way to *unload* the cert file, lets not
+		// do that.  (We might want to consider a mode to reset.)
+	}
+#endif
+
+	rv = nni_plat_tcp_ep_init(&c->tep, NULL, &sa, NNI_EP_MODE_DIAL);
+	if (rv != 0) {
+		nni_http_client_fini(c);
+		return (rv);
+	}
 
 	if ((rv = nni_aio_init(&c->connaio, http_conn_done, c)) != 0) {
 		nni_http_client_fini(c);
@@ -121,10 +193,10 @@ nni_http_client_init(nni_http_client **cp, nng_sockaddr *sa)
 	return (0);
 }
 
-#ifdef NNG_SUPP_TLS
 int
 nni_http_client_set_tls(nni_http_client *c, nng_tls_config *tls)
 {
+#ifdef NNG_SUPP_TLS
 	nng_tls_config *old;
 	nni_mtx_lock(&c->mtx);
 	old    = c->tls;
@@ -137,8 +209,27 @@ nni_http_client_set_tls(nni_http_client *c, nng_tls_config *tls)
 		nni_tls_config_fini(old);
 	}
 	return (0);
+#else
+	return (NNG_EINVAL);
+#endif
 }
+
+int
+nni_http_client_get_tls(nni_http_client *c, nng_tls_config **tlsp)
+{
+#ifdef NNG_SUPP_TLS
+	nni_mtx_lock(&c->mtx);
+	if (c->tls == NULL) {
+		nni_mtx_unlock(&c->mtx);
+		return (NNG_EINVAL);
+	}
+	*tlsp = c->tls;
+	nni_mtx_unlock(&c->mtx);
+	return (0);
+#else
+	return (NNG_ENOTSUP);
 #endif
+}
 
 static void
 http_connect_cancel(nni_aio *aio, int rv)