+int doit_biopair(SSL *s_ssl, SSL *c_ssl, long count)
+ {
+ long cw_num = count, cr_num = count, sw_num = count, sr_num = count;
+ BIO *s_ssl_bio = NULL, *c_ssl_bio = NULL;
+ BIO *server = NULL, *server_io = NULL, *client = NULL, *client_io = NULL;
+ SSL_CIPHER *ciph;
+ int ret = 1;
+
+ size_t bufsiz = 256; /* small buffer for testing */
+
+ if (!BIO_new_bio_pair(&server, bufsiz, &server_io, bufsiz))
+ goto err;
+ if (!BIO_new_bio_pair(&client, bufsiz, &client_io, bufsiz))
+ goto err;
+
+ s_ssl_bio = BIO_new(BIO_f_ssl());
+ if (!s_ssl_bio)
+ goto err;
+
+ c_ssl_bio = BIO_new(BIO_f_ssl());
+ if (!c_ssl_bio)
+ goto err;
+
+ SSL_set_connect_state(c_ssl);
+ SSL_set_bio(c_ssl, client, client);
+ (void)BIO_set_ssl(c_ssl_bio, c_ssl, BIO_NOCLOSE);
+
+ SSL_set_accept_state(s_ssl);
+ SSL_set_bio(s_ssl, server, server);
+ (void)BIO_set_ssl(s_ssl_bio, s_ssl, BIO_NOCLOSE);
+
+ do
+ {
+ /* c_ssl_bio: SSL filter BIO
+ *
+ * client: pseudo-I/O for SSL library
+ *
+ * client_io: client's SSL communication; usually to be
+ * relayed over some I/O facility, but in this
+ * test program, we're the server, too:
+ *
+ * server_io: server's SSL communication
+ *
+ * server: pseudo-I/O for SSL library
+ *
+ * s_ssl_bio: SSL filter BIO
+ *
+ * The client and the server each employ a "BIO pair":
+ * client + client_io, server + server_io.
+ * BIO pairs are symmetric. A BIO pair behaves similar
+ * to a non-blocking socketpair (but both endpoints must
+ * be handled by the same thread).
+ *
+ * Useful functions for querying the state of BIO pair endpoints:
+ *
+ * BIO_ctrl_pending(bio) number of bytes we can read now
+ * BIO_ctrl_get_read_request(bio) number of bytes needed to fulfil
+ * other side's read attempt
+ * BIO_ctrl_get_write_gurantee(bio) number of bytes we can write now
+ *
+ * ..._read_request is never more than ..._write_guarantee;
+ * it depends on the application which one you should use.
+ */
+
+ /* We have non-blocking behaviour throughout this test program, but
+ * can be sure that there is *some* progress in each iteration; so
+ * we don't have to worry about ..._SHOULD_READ or ..._SHOULD_WRITE
+ * -- we just try everything in each iteration
+ */
+
+ {
+ /* CLIENT */
+
+ MS_STATIC char cbuf[1024*8];
+ int i, r;
+
+ if (debug)
+ if (SSL_in_init(c_ssl))
+ printf("client waiting in SSL_connect - %s\n",
+ SSL_state_string_long(c_ssl));
+
+ if (cw_num > 0)
+ {
+ /* Write to server. */
+
+ if (cw_num > (long)sizeof cbuf)
+ i = sizeof cbuf;
+ else
+ i = (int)cw_num;
+ r = BIO_write(c_ssl_bio, cbuf, i);
+ if (r == -1)
+ {
+ if (!BIO_should_retry(c_ssl_bio))
+ {
+ fprintf(stderr,"ERROR in CLIENT\n");
+ goto err;
+ }
+ /* BIO_should_retry(...) can just be ignored here.
+ * The library expects us to call BIO_write with
+ * the same arguments again, and that's what we will
+ * do in the next iteration. */
+ }
+ else if (r == 0)
+ {
+ fprintf(stderr,"SSL CLIENT STARTUP FAILED\n");
+ goto err;
+ }
+ else
+ {
+ if (debug)
+ printf("client wrote %d\n", r);
+ cw_num -= r;
+ }
+ }
+
+ if (cr_num > 0)
+ {
+ /* Read from server. */
+
+ r = BIO_read(c_ssl_bio, cbuf, sizeof(cbuf));
+ if (r < 0)
+ {
+ if (!BIO_should_retry(c_ssl_bio))
+ {
+ fprintf(stderr,"ERROR in CLIENT\n");
+ goto err;
+ }
+ /* Again, "BIO_should_retry" can be ignored. */
+ }
+ else if (r == 0)
+ {
+ fprintf(stderr,"SSL CLIENT STARTUP FAILED\n");
+ goto err;
+ }
+ else
+ {
+ if (debug)
+ printf("client read %d\n", r);
+ cr_num -= r;
+ }
+ }
+ }
+
+ {
+ /* SERVER */
+
+ MS_STATIC char sbuf[1024*8];
+ int i, r;
+
+ if (debug)
+ if (SSL_in_init(s_ssl))
+ printf("server waiting in SSL_accept - %s\n",
+ SSL_state_string_long(s_ssl));
+
+ if (sw_num > 0)
+ {
+ /* Write to client. */
+
+ if (sw_num > (long)sizeof sbuf)
+ i = sizeof sbuf;
+ else
+ i = (int)sw_num;
+ r = BIO_write(s_ssl_bio, sbuf, i);
+ if (r == -1)
+ {
+ if (!BIO_should_retry(s_ssl_bio))
+ {
+ fprintf(stderr,"ERROR in SERVER\n");
+ goto err;
+ }
+ /* Ignore "BIO_should_retry". */
+ }
+ else if (r == 0)
+ {
+ fprintf(stderr,"SSL SERVER STARTUP FAILED\n");
+ goto err;
+ }
+ else
+ {
+ if (debug)
+ printf("server wrote %d\n", r);
+ sw_num -= r;
+ }
+ }
+
+ if (sr_num > 0)
+ {
+ /* Read from client. */
+
+ r = BIO_read(s_ssl_bio, sbuf, sizeof(sbuf));
+ if (r < 0)
+ {
+ if (!BIO_should_retry(s_ssl_bio))
+ {
+ fprintf(stderr,"ERROR in SERVER\n");
+ goto err;
+ }
+ /* blah, blah */
+ }
+ else if (r == 0)
+ {
+ fprintf(stderr,"SSL SERVER STARTUP FAILED\n");
+ goto err;
+ }
+ else
+ {
+ if (debug)
+ printf("server read %d\n", r);
+ sr_num -= r;
+ }
+ }
+ }
+
+ {
+ /* "I/O" BETWEEN CLIENT AND SERVER. */
+
+#define RELAYBUFSIZ 200
+ static char buf[RELAYBUFSIZ];
+
+ /* RELAYBUF is arbitrary. When writing data over some real
+ * network, use a buffer of the same size as in the BIO_pipe
+ * and make that size large (for reading from the network
+ * small buffers usually won't hurt).
+ * Here sizes differ for testing. */
+
+ size_t r1, r2;
+ size_t num;
+ int r;
+ static int prev_progress = 1;
+ int progress = 0;
+
+ /* client to server */
+ do
+ {
+ r1 = BIO_ctrl_pending(client_io);
+ r2 = BIO_ctrl_get_write_guarantee(server_io);
+
+ num = r1;
+ if (r2 < num)
+ num = r2;
+ if (num)
+ {
+ if (sizeof buf < num)
+ num = sizeof buf;
+ if (INT_MAX < num) /* yeah, right */
+ num = INT_MAX;
+
+ r = BIO_read(client_io, buf, (int)num);
+ if (r != (int)num) /* can't happen */
+ {
+ fprintf(stderr, "ERROR: BIO_read could not read "
+ "BIO_ctrl_pending() bytes");
+ goto err;
+ }
+ r = BIO_write(server_io, buf, (int)num);
+ if (r != (int)num) /* can't happen */
+ {
+ fprintf(stderr, "ERROR: BIO_write could not write "
+ "BIO_ctrl_get_write_guarantee() bytes");
+ goto err;
+ }
+ progress = 1;
+
+ if (debug)
+ printf("C->S relaying: %d bytes\n", (int)num);
+ }
+ }
+ while (r1 && r2);
+
+ /* server to client */
+ do
+ {
+ r1 = BIO_ctrl_pending(server_io);
+ r2 = BIO_ctrl_get_write_guarantee(client_io);
+
+ num = r1;
+ if (r2 < num)
+ num = r2;
+ if (num)
+ {
+ if (sizeof buf < num)
+ num = sizeof buf;
+ if (INT_MAX < num)
+ num = INT_MAX;
+
+ r = BIO_read(server_io, buf, (int)num);
+ if (r != (int)num) /* can't happen */
+ {
+ fprintf(stderr, "ERROR: BIO_read could not read "
+ "BIO_ctrl_pending() bytes");
+ goto err;
+ }
+ r = BIO_write(client_io, buf, (int)num);
+ if (r != (int)num) /* can't happen */
+ {
+ fprintf(stderr, "ERROR: BIO_write could not write "
+ "BIO_ctrl_get_write_guarantee() bytes");
+ goto err;
+ }
+ progress = 1;
+
+ if (debug)
+ printf("S->C relaying: %d bytes\n", (int)num);
+ }
+ }
+ while (r1 && r2);
+
+ if (!progress && !prev_progress)
+ if (cw_num > 0 || cr_num > 0 || sw_num > 0 || sr_num > 0)
+ {
+ fprintf(stderr, "ERROR: got stuck\n");
+ if (strcmp("SSLv2", SSL_get_version(c_ssl)) == 0)
+ {
+ fprintf(stderr, "This can happen for SSL2 because "
+ "CLIENT-FINISHED and SERVER-VERIFY are written \n"
+ "concurrently ...");
+ if (strncmp("2SCF", SSL_state_string(c_ssl), 4) == 0
+ && strncmp("2SSV", SSL_state_string(s_ssl), 4) == 0)
+ {
+ fprintf(stderr, " ok.\n");
+ goto end;
+ }
+ }
+ fprintf(stderr, " ERROR.\n");
+ goto err;
+ }
+ prev_progress = progress;
+ }
+ }
+ while (cw_num > 0 || cr_num > 0 || sw_num > 0 || sr_num > 0);
+
+ ciph = SSL_get_current_cipher(c_ssl);
+ if (verbose)
+ fprintf(stdout,"DONE via BIO pair, protocol %s, cipher %s, %s\n",
+ SSL_get_version(c_ssl),
+ SSL_CIPHER_get_version(ciph),
+ SSL_CIPHER_get_name(ciph));
+ end:
+ ret = 0;
+
+ err:
+ ERR_print_errors(bio_err);
+
+ if (server)
+ BIO_free(server);
+ if (server_io)
+ BIO_free(server_io);
+ if (client)
+ BIO_free(client);
+ if (client_io)
+ BIO_free(client_io);
+ if (s_ssl_bio)
+ BIO_free(s_ssl_bio);
+ if (c_ssl_bio)
+ BIO_free(c_ssl_bio);
+
+ return ret;
+ }
+
+