Test TLS interoperability between LibreSSL and OpenSSL.

Implement simple SSL client and server in C.  Create four binaries
by linking them with LibreSSL or OpenSSL.  This way API compatibility
is tested.  Connect and accept with netcat to test protocol
compatibility with libtls.

Currently OpenSSL 1.0.2p from ports is used.  Plan is to move to
OpenSSL 1.1 and and test TLS 1.3.

idea from beck@; help from jsing@

1 files changed, 136 insertions, 0 deletions

diff --git a/src/regress/lib/libssl/interop/client.c b/src/regress/lib/libssl/interop/client.c
new file mode 100644
index 0000000000..d4d4f1e94d
--- /dev/null
+++ b/src/regress/lib/libssl/interop/client.c
@@ -0,0 +1,136 @@
+/*      $OpenBSD: client.c,v 1.1.1.1 2018/11/07 01:08:49 bluhm Exp $    */
+/*
+ * Copyright (c) 2018 Alexander Bluhm <bluhm@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <err.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include <openssl/err.h>
+#include <openssl/ssl.h>
+
+#include "util.h"
+
+void __dead usage(void);
+
+void __dead
+usage(void)
+{
+        fprintf(stderr, "usage: client host port");
+        exit(2);
+}
+
+int
+main(int argc, char *argv[])
+{
+        const SSL_METHOD *method;
+        SSL_CTX *ctx;
+        SSL *ssl;
+        BIO *bio;
+        SSL_SESSION *session;
+        int error;
+        char buf[256];
+        char *host_port, *host, *port;
+
+        if (argc == 3) {
+                host = argv[1];
+                port = argv[2];
+        } else {
+                usage();
+        }
+        if (asprintf(&host_port, strchr(host, ':') ? "[%s]:%s" : "%s:%s",
+            host, port) == -1)
+                err(1, "asprintf host port");
+
+        SSL_library_init();
+        SSL_load_error_strings();
+
+        /* setup method and context */
+        method = SSLv23_client_method();
+        if (method == NULL)
+                err_ssl(1, "SSLv23_client_method");
+        ctx = SSL_CTX_new(method);
+        if (ctx == NULL)
+                err_ssl(1, "SSL_CTX_new");
+
+        /* setup ssl and bio for socket operations */
+        ssl = SSL_new(ctx);
+        if (ssl == NULL)
+                err_ssl(1, "SSL_new");
+        bio = BIO_new_connect(host_port);
+        if (bio == NULL)
+                err_ssl(1, "BIO_new_connect");
+
+        print_ciphers(SSL_get_ciphers(ssl));
+
+        /* connect */
+        if (BIO_do_connect(bio) <= 0)
+                err_ssl(1, "BIO_do_connect");
+        printf("connect ");
+        print_sockname(bio);
+        printf("connect ");
+        print_peername(bio);
+
+        /* do ssl client handshake */
+        SSL_set_bio(ssl, bio, bio);
+        if ((error = SSL_connect(ssl)) <= 0)
+                err_ssl(1, "SSL_connect %d", error);
+
+        /* print session statistics */
+        session = SSL_get_session(ssl);
+        if (session == NULL)
+                err_ssl(1, "SSL_get_session");
+        if (SSL_SESSION_print_fp(stdout, session) <= 0)
+                err_ssl(1, "SSL_SESSION_print_fp");
+
+        /* read server greeting and write client hello over TLS connection */
+        if ((error = SSL_read(ssl, buf, 9)) <= 0)
+                err_ssl(1, "SSL_read %d", error);
+        if (error != 9)
+                errx(1, "read not 9 bytes greeting: %d", error);
+        buf[9] = '\0';
+        printf("<<< %s", buf);
+        if (fflush(stdout) != 0)
+                err(1, "fflush stdout");
+        strlcpy(buf, "hello\n", sizeof(buf));
+        printf(">>> %s", buf);
+        if (fflush(stdout) != 0)
+                err(1, "fflush stdout");
+        if ((error = SSL_write(ssl, buf, 6)) <= 0)
+                err_ssl(1, "SSL_write %d", error);
+        if (error != 6)
+                errx(1, "write not 6 bytes hello: %d", error);
+
+        /* shutdown connection */
+        if ((error = SSL_shutdown(ssl)) < 0)
+                err_ssl(1, "SSL_shutdown unidirectional %d", error);
+        if (error <= 0) {
+                if ((error = SSL_shutdown(ssl)) <= 0)
+                        err_ssl(1, "SSL_shutdown bidirectional %d", error);
+        }
+
+        /* cleanup and free resources */
+        SSL_free(ssl);
+        SSL_CTX_free(ctx);
+
+        printf("success\n");
+
+        return 0;
+}