Add support to test_ssl_new for testing with DTLS over SCTP
[openssl.git] / test / handshake_helper.c
index 0a27324899c569b292e095e0a99be95b18039231..4943e82d83a1c9440fb177a5532b8c2599e97789 100644 (file)
@@ -1,11 +1,10 @@
 /*
  * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
  *
- * Licensed under the OpenSSL licenses, (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
+ * Licensed under the OpenSSL license (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
  * https://www.openssl.org/source/license.html
- * or in the file LICENSE in the source distribution.
  */
 
 #include <string.h>
 #include <openssl/bio.h>
 #include <openssl/x509_vfy.h>
 #include <openssl/ssl.h>
+#ifndef OPENSSL_NO_SRP
+#include <openssl/srp.h>
+#endif
+
+#ifndef OPENSSL_NO_SOCK
+# define USE_SOCKETS
+# include "e_os.h"
+#endif
 
 #include "handshake_helper.h"
+#include "testutil.h"
+
+HANDSHAKE_RESULT *HANDSHAKE_RESULT_new()
+{
+    HANDSHAKE_RESULT *ret = OPENSSL_zalloc(sizeof(*ret));
+    TEST_check(ret != NULL);
+    return ret;
+}
+
+void HANDSHAKE_RESULT_free(HANDSHAKE_RESULT *result)
+{
+    if (result == NULL)
+        return;
+    OPENSSL_free(result->client_npn_negotiated);
+    OPENSSL_free(result->server_npn_negotiated);
+    OPENSSL_free(result->client_alpn_negotiated);
+    OPENSSL_free(result->server_alpn_negotiated);
+    sk_X509_NAME_pop_free(result->server_ca_names, X509_NAME_free);
+    sk_X509_NAME_pop_free(result->client_ca_names, X509_NAME_free);
+    OPENSSL_free(result);
+}
 
 /*
  * Since there appears to be no way to extract the sent/received alert
  * from the SSL object directly, we use the info callback and stash
  * the result in ex_data.
  */
-typedef struct handshake_ex_data {
+typedef struct handshake_ex_data_st {
     int alert_sent;
+    int num_fatal_alerts_sent;
     int alert_received;
+    int session_ticket_do_not_call;
+    ssl_servername_t servername;
 } HANDSHAKE_EX_DATA;
 
+typedef struct ctx_data_st {
+    unsigned char *npn_protocols;
+    size_t npn_protocols_len;
+    unsigned char *alpn_protocols;
+    size_t alpn_protocols_len;
+    char *srp_user;
+    char *srp_password;
+} CTX_DATA;
+
+/* |ctx_data| itself is stack-allocated. */
+static void ctx_data_free_data(CTX_DATA *ctx_data)
+{
+    OPENSSL_free(ctx_data->npn_protocols);
+    ctx_data->npn_protocols = NULL;
+    OPENSSL_free(ctx_data->alpn_protocols);
+    ctx_data->alpn_protocols = NULL;
+    OPENSSL_free(ctx_data->srp_user);
+    ctx_data->srp_user = NULL;
+    OPENSSL_free(ctx_data->srp_password);
+    ctx_data->srp_password = NULL;
+}
+
 static int ex_data_idx;
 
-static void info_callback(const SSL *s, int where, int ret)
+static void info_cb(const SSL *s, int where, int ret)
 {
     if (where & SSL_CB_ALERT) {
         HANDSHAKE_EX_DATA *ex_data =
             (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));
         if (where & SSL_CB_WRITE) {
             ex_data->alert_sent = ret;
+            if (strcmp(SSL_alert_type_string(ret), "F") == 0
+                || strcmp(SSL_alert_desc_string(ret), "CN") == 0)
+                ex_data->num_fatal_alerts_sent++;
         } else {
             ex_data->alert_received = ret;
         }
     }
 }
 
-static int verify_reject_callback(X509_STORE_CTX *ctx, void *arg) {
+/* Select the appropriate server CTX.
+ * Returns SSL_TLSEXT_ERR_OK if a match was found.
+ * If |ignore| is 1, returns SSL_TLSEXT_ERR_NOACK on mismatch.
+ * Otherwise, returns SSL_TLSEXT_ERR_ALERT_FATAL on mismatch.
+ * An empty SNI extension also returns SSL_TSLEXT_ERR_NOACK.
+ */
+static int select_server_ctx(SSL *s, void *arg, int ignore)
+{
+    const char *servername = SSL_get_servername(s, TLSEXT_NAMETYPE_host_name);
+    HANDSHAKE_EX_DATA *ex_data =
+        (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));
+
+    if (servername == NULL) {
+        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
+        return SSL_TLSEXT_ERR_NOACK;
+    }
+
+    if (strcmp(servername, "server2") == 0) {
+        SSL_CTX *new_ctx = (SSL_CTX*)arg;
+        SSL_set_SSL_CTX(s, new_ctx);
+        /*
+         * Copy over all the SSL_CTX options - reasonable behavior
+         * allows testing of cases where the options between two
+         * contexts differ/conflict
+         */
+        SSL_clear_options(s, 0xFFFFFFFFL);
+        SSL_set_options(s, SSL_CTX_get_options(new_ctx));
+
+        ex_data->servername = SSL_TEST_SERVERNAME_SERVER2;
+        return SSL_TLSEXT_ERR_OK;
+    } else if (strcmp(servername, "server1") == 0) {
+        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
+        return SSL_TLSEXT_ERR_OK;
+    } else if (ignore) {
+        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
+        return SSL_TLSEXT_ERR_NOACK;
+    } else {
+        /* Don't set an explicit alert, to test library defaults. */
+        return SSL_TLSEXT_ERR_ALERT_FATAL;
+    }
+}
+
+static int early_select_server_ctx(SSL *s, void *arg, int ignore)
+{
+    const char *servername;
+    const unsigned char *p;
+    size_t len, remaining;
+    HANDSHAKE_EX_DATA *ex_data =
+        (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));
+
+    /*
+     * The server_name extension was given too much extensibility when it
+     * was written, so parsing the normal case is a bit complex.
+     */
+    if (!SSL_early_get0_ext(s, TLSEXT_TYPE_server_name, &p, &remaining) ||
+        remaining <= 2)
+        return 0;
+    /* Extract the length of the supplied list of names. */
+    len = (*(p++) << 1);
+    len += *(p++);
+    if (len + 2 != remaining)
+        return 0;
+    remaining = len;
+    /*
+     * The list in practice only has a single element, so we only consider
+     * the first one.
+     */
+    if (remaining == 0 || *p++ != TLSEXT_NAMETYPE_host_name)
+        return 0;
+    remaining--;
+    /* Now we can finally pull out the byte array with the actual hostname. */
+    if (remaining <= 2)
+        return 0;
+    len = (*(p++) << 1);
+    len += *(p++);
+    if (len + 2 > remaining)
+        return 0;
+    remaining = len;
+    servername = (const char *)p;
+
+    if (len == strlen("server2") && strncmp(servername, "server2", len) == 0) {
+        SSL_CTX *new_ctx = arg;
+        SSL_set_SSL_CTX(s, new_ctx);
+        /*
+         * Copy over all the SSL_CTX options - reasonable behavior
+         * allows testing of cases where the options between two
+         * contexts differ/conflict
+         */
+        SSL_clear_options(s, 0xFFFFFFFFL);
+        SSL_set_options(s, SSL_CTX_get_options(new_ctx));
+
+        ex_data->servername = SSL_TEST_SERVERNAME_SERVER2;
+        return 1;
+    } else if (len == strlen("server1") &&
+               strncmp(servername, "server1", len) == 0) {
+        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
+        return 1;
+    } else if (ignore) {
+        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
+        return 1;
+    }
+    return 0;
+}
+/*
+ * (RFC 6066):
+ *  If the server understood the ClientHello extension but
+ *  does not recognize the server name, the server SHOULD take one of two
+ *  actions: either abort the handshake by sending a fatal-level
+ *  unrecognized_name(112) alert or continue the handshake.
+ *
+ * This behaviour is up to the application to configure; we test both
+ * configurations to ensure the state machine propagates the result
+ * correctly.
+ */
+static int servername_ignore_cb(SSL *s, int *ad, void *arg)
+{
+    return select_server_ctx(s, arg, 1);
+}
+
+static int servername_reject_cb(SSL *s, int *ad, void *arg)
+{
+    return select_server_ctx(s, arg, 0);
+}
+
+static int early_ignore_cb(SSL *s, int *al, void *arg)
+{
+    if (!early_select_server_ctx(s, arg, 1)) {
+        *al = SSL_AD_UNRECOGNIZED_NAME;
+        return 0;
+    }
+    return 1;
+}
+
+static int early_reject_cb(SSL *s, int *al, void *arg)
+{
+    if (!early_select_server_ctx(s, arg, 0)) {
+        *al = SSL_AD_UNRECOGNIZED_NAME;
+        return 0;
+    }
+    return 1;
+}
+
+static int early_nov12_cb(SSL *s, int *al, void *arg)
+{
+    int ret;
+    unsigned int v;
+    const unsigned char *p;
+
+    v = SSL_early_get0_legacy_version(s);
+    if (v > TLS1_2_VERSION || v < SSL3_VERSION) {
+        *al = SSL_AD_PROTOCOL_VERSION;
+        return 0;
+    }
+    (void)SSL_early_get0_session_id(s, &p);
+    if (p == NULL ||
+        SSL_early_get0_random(s, &p) == 0 ||
+        SSL_early_get0_ciphers(s, &p) == 0 ||
+        SSL_early_get0_compression_methods(s, &p) == 0) {
+        *al = SSL_AD_INTERNAL_ERROR;
+        return 0;
+    }
+    ret = early_select_server_ctx(s, arg, 0);
+    SSL_set_max_proto_version(s, TLS1_1_VERSION);
+    if (!ret)
+        *al = SSL_AD_UNRECOGNIZED_NAME;
+    return ret;
+}
+
+static unsigned char dummy_ocsp_resp_good_val = 0xff;
+static unsigned char dummy_ocsp_resp_bad_val = 0xfe;
+
+static int server_ocsp_cb(SSL *s, void *arg)
+{
+    unsigned char *resp;
+
+    resp = OPENSSL_malloc(1);
+    if (resp == NULL)
+        return SSL_TLSEXT_ERR_ALERT_FATAL;
+    /*
+     * For the purposes of testing we just send back a dummy OCSP response
+     */
+    *resp = *(unsigned char *)arg;
+    if (!SSL_set_tlsext_status_ocsp_resp(s, resp, 1))
+        return SSL_TLSEXT_ERR_ALERT_FATAL;
+
+    return SSL_TLSEXT_ERR_OK;
+}
+
+static int client_ocsp_cb(SSL *s, void *arg)
+{
+    const unsigned char *resp;
+    int len;
+
+    len = SSL_get_tlsext_status_ocsp_resp(s, &resp);
+    if (len != 1 || *resp != dummy_ocsp_resp_good_val)
+        return 0;
+
+    return 1;
+}
+
+static int verify_reject_cb(X509_STORE_CTX *ctx, void *arg) {
     X509_STORE_CTX_set_error(ctx, X509_V_ERR_APPLICATION_VERIFICATION);
     return 0;
 }
 
-static int verify_accept_callback(X509_STORE_CTX *ctx, void *arg) {
+static int verify_accept_cb(X509_STORE_CTX *ctx, void *arg) {
     return 1;
 }
 
+static int broken_session_ticket_cb(SSL *s, unsigned char *key_name, unsigned char *iv,
+                                    EVP_CIPHER_CTX *ctx, HMAC_CTX *hctx, int enc)
+{
+    return 0;
+}
+
+static int do_not_call_session_ticket_cb(SSL *s, unsigned char *key_name,
+                                         unsigned char *iv,
+                                         EVP_CIPHER_CTX *ctx,
+                                         HMAC_CTX *hctx, int enc)
+{
+    HANDSHAKE_EX_DATA *ex_data =
+        (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));
+    ex_data->session_ticket_do_not_call = 1;
+    return 0;
+}
+
+/* Parse the comma-separated list into TLS format. */
+static void parse_protos(const char *protos, unsigned char **out, size_t *outlen)
+{
+    size_t len, i, prefix;
+
+    len = strlen(protos);
+
+    /* Should never have reuse. */
+    TEST_check(*out == NULL);
+
+    /* Test values are small, so we omit length limit checks. */
+    *out = OPENSSL_malloc(len + 1);
+    TEST_check(*out != NULL);
+    *outlen = len + 1;
+
+    /*
+     * foo => '3', 'f', 'o', 'o'
+     * foo,bar => '3', 'f', 'o', 'o', '3', 'b', 'a', 'r'
+     */
+    memcpy(*out + 1, protos, len);
+
+    prefix = 0;
+    i = prefix + 1;
+    while (i <= len) {
+        if ((*out)[i] == ',') {
+            TEST_check(i - 1 - prefix > 0);
+            (*out)[prefix] = i - 1 - prefix;
+            prefix = i;
+        }
+        i++;
+    }
+    TEST_check(len - prefix > 0);
+    (*out)[prefix] = len - prefix;
+}
+
+#ifndef OPENSSL_NO_NEXTPROTONEG
+/*
+ * The client SHOULD select the first protocol advertised by the server that it
+ * also supports.  In the event that the client doesn't support any of server's
+ * protocols, or the server doesn't advertise any, it SHOULD select the first
+ * protocol that it supports.
+ */
+static int client_npn_cb(SSL *s, unsigned char **out, unsigned char *outlen,
+                         const unsigned char *in, unsigned int inlen,
+                         void *arg)
+{
+    CTX_DATA *ctx_data = (CTX_DATA*)(arg);
+    int ret;
+
+    ret = SSL_select_next_proto(out, outlen, in, inlen,
+                                ctx_data->npn_protocols,
+                                ctx_data->npn_protocols_len);
+    /* Accept both OPENSSL_NPN_NEGOTIATED and OPENSSL_NPN_NO_OVERLAP. */
+    TEST_check(ret == OPENSSL_NPN_NEGOTIATED || ret == OPENSSL_NPN_NO_OVERLAP);
+    return SSL_TLSEXT_ERR_OK;
+}
+
+static int server_npn_cb(SSL *s, const unsigned char **data,
+                         unsigned int *len, void *arg)
+{
+    CTX_DATA *ctx_data = (CTX_DATA*)(arg);
+    *data = ctx_data->npn_protocols;
+    *len = ctx_data->npn_protocols_len;
+    return SSL_TLSEXT_ERR_OK;
+}
+#endif
+
+/*
+ * The server SHOULD select the most highly preferred protocol that it supports
+ * and that is also advertised by the client.  In the event that the server
+ * supports no protocols that the client advertises, then the server SHALL
+ * respond with a fatal "no_application_protocol" alert.
+ */
+static int server_alpn_cb(SSL *s, const unsigned char **out,
+                          unsigned char *outlen, const unsigned char *in,
+                          unsigned int inlen, void *arg)
+{
+    CTX_DATA *ctx_data = (CTX_DATA*)(arg);
+    int ret;
+
+    /* SSL_select_next_proto isn't const-correct... */
+    unsigned char *tmp_out;
+
+    /*
+     * The result points either to |in| or to |ctx_data->alpn_protocols|.
+     * The callback is allowed to point to |in| or to a long-lived buffer,
+     * so we can return directly without storing a copy.
+     */
+    ret = SSL_select_next_proto(&tmp_out, outlen,
+                                ctx_data->alpn_protocols,
+                                ctx_data->alpn_protocols_len, in, inlen);
+
+    *out = tmp_out;
+    /* Unlike NPN, we don't tolerate a mismatch. */
+    return ret == OPENSSL_NPN_NEGOTIATED ? SSL_TLSEXT_ERR_OK
+        : SSL_TLSEXT_ERR_ALERT_FATAL;
+}
+
+#ifndef OPENSSL_NO_SRP
+static char *client_srp_cb(SSL *s, void *arg)
+{
+    CTX_DATA *ctx_data = (CTX_DATA*)(arg);
+    return OPENSSL_strdup(ctx_data->srp_password);
+}
+
+static int server_srp_cb(SSL *s, int *ad, void *arg)
+{
+    CTX_DATA *ctx_data = (CTX_DATA*)(arg);
+    if (strcmp(ctx_data->srp_user, SSL_get_srp_username(s)) != 0)
+        return SSL3_AL_FATAL;
+    if (SSL_set_srp_server_param_pw(s, ctx_data->srp_user,
+                                    ctx_data->srp_password,
+                                    "2048" /* known group */) < 0) {
+        *ad = SSL_AD_INTERNAL_ERROR;
+        return SSL3_AL_FATAL;
+    }
+    return SSL_ERROR_NONE;
+}
+#endif  /* !OPENSSL_NO_SRP */
+
 /*
  * Configure callbacks and other properties that can't be set directly
  * in the server/client CONF.
  */
-static void configure_handshake(SSL_CTX *server_ctx, SSL_CTX *client_ctx,
-                                const SSL_TEST_CTX *test_ctx)
+static void configure_handshake_ctx(SSL_CTX *server_ctx, SSL_CTX *server2_ctx,
+                                    SSL_CTX *client_ctx,
+                                    const SSL_TEST_CTX *test,
+                                    const SSL_TEST_EXTRA_CONF *extra,
+                                    CTX_DATA *server_ctx_data,
+                                    CTX_DATA *server2_ctx_data,
+                                    CTX_DATA *client_ctx_data)
 {
-    switch (test_ctx->client_verify_callback) {
+    unsigned char *ticket_keys;
+    size_t ticket_key_len;
+
+    TEST_check(SSL_CTX_set_max_send_fragment(server_ctx,
+                                             test->max_fragment_size) == 1);
+    if (server2_ctx != NULL) {
+        TEST_check(SSL_CTX_set_max_send_fragment(server2_ctx,
+                                                 test->max_fragment_size) == 1);
+    }
+    TEST_check(SSL_CTX_set_max_send_fragment(client_ctx,
+                                             test->max_fragment_size) == 1);
+
+    switch (extra->client.verify_callback) {
     case SSL_TEST_VERIFY_ACCEPT_ALL:
-        SSL_CTX_set_cert_verify_callback(client_ctx, &verify_accept_callback,
+        SSL_CTX_set_cert_verify_callback(client_ctx, &verify_accept_cb,
                                          NULL);
         break;
     case SSL_TEST_VERIFY_REJECT_ALL:
-        SSL_CTX_set_cert_verify_callback(client_ctx, &verify_reject_callback,
+        SSL_CTX_set_cert_verify_callback(client_ctx, &verify_reject_cb,
                                          NULL);
         break;
-    default:
+    case SSL_TEST_VERIFY_NONE:
         break;
     }
+
+    /*
+     * Link the two contexts for SNI purposes.
+     * Also do early callbacks here, as setting both early and SNI is bad.
+     */
+    switch (extra->server.servername_callback) {
+    case SSL_TEST_SERVERNAME_IGNORE_MISMATCH:
+        SSL_CTX_set_tlsext_servername_callback(server_ctx, servername_ignore_cb);
+        SSL_CTX_set_tlsext_servername_arg(server_ctx, server2_ctx);
+        break;
+    case SSL_TEST_SERVERNAME_REJECT_MISMATCH:
+        SSL_CTX_set_tlsext_servername_callback(server_ctx, servername_reject_cb);
+        SSL_CTX_set_tlsext_servername_arg(server_ctx, server2_ctx);
+        break;
+    case SSL_TEST_SERVERNAME_CB_NONE:
+        break;
+    case SSL_TEST_SERVERNAME_EARLY_IGNORE_MISMATCH:
+        SSL_CTX_set_early_cb(server_ctx, early_ignore_cb, server2_ctx);
+        break;
+    case SSL_TEST_SERVERNAME_EARLY_REJECT_MISMATCH:
+        SSL_CTX_set_early_cb(server_ctx, early_reject_cb, server2_ctx);
+        break;
+    case SSL_TEST_SERVERNAME_EARLY_NO_V12:
+        SSL_CTX_set_early_cb(server_ctx, early_nov12_cb, server2_ctx);
+    }
+
+    if (extra->server.cert_status != SSL_TEST_CERT_STATUS_NONE) {
+        SSL_CTX_set_tlsext_status_type(client_ctx, TLSEXT_STATUSTYPE_ocsp);
+        SSL_CTX_set_tlsext_status_cb(client_ctx, client_ocsp_cb);
+        SSL_CTX_set_tlsext_status_arg(client_ctx, NULL);
+        SSL_CTX_set_tlsext_status_cb(server_ctx, server_ocsp_cb);
+        SSL_CTX_set_tlsext_status_arg(server_ctx,
+            ((extra->server.cert_status == SSL_TEST_CERT_STATUS_GOOD_RESPONSE)
+            ? &dummy_ocsp_resp_good_val : &dummy_ocsp_resp_bad_val));
+    }
+
+    /*
+     * The initial_ctx/session_ctx always handles the encrypt/decrypt of the
+     * session ticket. This ticket_key callback is assigned to the second
+     * session (assigned via SNI), and should never be invoked
+     */
+    if (server2_ctx != NULL)
+        SSL_CTX_set_tlsext_ticket_key_cb(server2_ctx,
+                                         do_not_call_session_ticket_cb);
+
+    if (extra->server.broken_session_ticket) {
+        SSL_CTX_set_tlsext_ticket_key_cb(server_ctx, broken_session_ticket_cb);
+    }
+#ifndef OPENSSL_NO_NEXTPROTONEG
+    if (extra->server.npn_protocols != NULL) {
+        parse_protos(extra->server.npn_protocols,
+                     &server_ctx_data->npn_protocols,
+                     &server_ctx_data->npn_protocols_len);
+        SSL_CTX_set_npn_advertised_cb(server_ctx, server_npn_cb,
+                                      server_ctx_data);
+    }
+    if (extra->server2.npn_protocols != NULL) {
+        parse_protos(extra->server2.npn_protocols,
+                     &server2_ctx_data->npn_protocols,
+                     &server2_ctx_data->npn_protocols_len);
+        TEST_check(server2_ctx != NULL);
+        SSL_CTX_set_npn_advertised_cb(server2_ctx, server_npn_cb,
+                                      server2_ctx_data);
+    }
+    if (extra->client.npn_protocols != NULL) {
+        parse_protos(extra->client.npn_protocols,
+                     &client_ctx_data->npn_protocols,
+                     &client_ctx_data->npn_protocols_len);
+        SSL_CTX_set_next_proto_select_cb(client_ctx, client_npn_cb,
+                                         client_ctx_data);
+    }
+#endif
+    if (extra->server.alpn_protocols != NULL) {
+        parse_protos(extra->server.alpn_protocols,
+                     &server_ctx_data->alpn_protocols,
+                     &server_ctx_data->alpn_protocols_len);
+        SSL_CTX_set_alpn_select_cb(server_ctx, server_alpn_cb, server_ctx_data);
+    }
+    if (extra->server2.alpn_protocols != NULL) {
+        TEST_check(server2_ctx != NULL);
+        parse_protos(extra->server2.alpn_protocols,
+                     &server2_ctx_data->alpn_protocols,
+                     &server2_ctx_data->alpn_protocols_len);
+        SSL_CTX_set_alpn_select_cb(server2_ctx, server_alpn_cb, server2_ctx_data);
+    }
+    if (extra->client.alpn_protocols != NULL) {
+        unsigned char *alpn_protos = NULL;
+        size_t alpn_protos_len;
+        parse_protos(extra->client.alpn_protocols,
+                     &alpn_protos, &alpn_protos_len);
+        /* Reversed return value convention... */
+        TEST_check(SSL_CTX_set_alpn_protos(client_ctx, alpn_protos,
+                                           alpn_protos_len) == 0);
+        OPENSSL_free(alpn_protos);
+    }
+
+    /*
+     * Use fixed session ticket keys so that we can decrypt a ticket created with
+     * one CTX in another CTX. Don't address server2 for the moment.
+     */
+    ticket_key_len = SSL_CTX_set_tlsext_ticket_keys(server_ctx, NULL, 0);
+    ticket_keys = OPENSSL_zalloc(ticket_key_len);
+    TEST_check(ticket_keys != NULL);
+    TEST_check(SSL_CTX_set_tlsext_ticket_keys(server_ctx, ticket_keys,
+                                              ticket_key_len) == 1);
+    OPENSSL_free(ticket_keys);
+
+    /* The default log list includes EC keys, so CT can't work without EC. */
+#if !defined(OPENSSL_NO_CT) && !defined(OPENSSL_NO_EC)
+    TEST_check(SSL_CTX_set_default_ctlog_list_file(client_ctx));
+    switch (extra->client.ct_validation) {
+    case SSL_TEST_CT_VALIDATION_PERMISSIVE:
+        TEST_check(SSL_CTX_enable_ct(client_ctx, SSL_CT_VALIDATION_PERMISSIVE));
+        break;
+    case SSL_TEST_CT_VALIDATION_STRICT:
+        TEST_check(SSL_CTX_enable_ct(client_ctx, SSL_CT_VALIDATION_STRICT));
+        break;
+    case SSL_TEST_CT_VALIDATION_NONE:
+        break;
+    }
+#endif
+#ifndef OPENSSL_NO_SRP
+    if (extra->server.srp_user != NULL) {
+        SSL_CTX_set_srp_username_callback(server_ctx, server_srp_cb);
+        server_ctx_data->srp_user = OPENSSL_strdup(extra->server.srp_user);
+        server_ctx_data->srp_password = OPENSSL_strdup(extra->server.srp_password);
+        SSL_CTX_set_srp_cb_arg(server_ctx, server_ctx_data);
+    }
+    if (extra->server2.srp_user != NULL) {
+        TEST_check(server2_ctx != NULL);
+        SSL_CTX_set_srp_username_callback(server2_ctx, server_srp_cb);
+        server2_ctx_data->srp_user = OPENSSL_strdup(extra->server2.srp_user);
+        server2_ctx_data->srp_password = OPENSSL_strdup(extra->server2.srp_password);
+        SSL_CTX_set_srp_cb_arg(server2_ctx, server2_ctx_data);
+    }
+    if (extra->client.srp_user != NULL) {
+        TEST_check(SSL_CTX_set_srp_username(client_ctx, extra->client.srp_user));
+        SSL_CTX_set_srp_client_pwd_callback(client_ctx, client_srp_cb);
+        client_ctx_data->srp_password = OPENSSL_strdup(extra->client.srp_password);
+        SSL_CTX_set_srp_cb_arg(client_ctx, client_ctx_data);
+    }
+#endif  /* !OPENSSL_NO_SRP */
 }
 
+/* Configure per-SSL callbacks and other properties. */
+static void configure_handshake_ssl(SSL *server, SSL *client,
+                                    const SSL_TEST_EXTRA_CONF *extra)
+{
+    if (extra->client.servername != SSL_TEST_SERVERNAME_NONE)
+        SSL_set_tlsext_host_name(client,
+                                 ssl_servername_name(extra->client.servername));
+}
 
+/* The status for each connection phase. */
 typedef enum {
     PEER_SUCCESS,
     PEER_RETRY,
-    PEER_ERROR
+    PEER_ERROR,
+    PEER_WAITING
 } peer_status_t;
 
-static peer_status_t do_handshake_step(SSL *ssl)
+/* An SSL object and associated read-write buffers. */
+typedef struct peer_st {
+    SSL *ssl;
+    /* Buffer lengths are int to match the SSL read/write API. */
+    unsigned char *write_buf;
+    int write_buf_len;
+    unsigned char *read_buf;
+    int read_buf_len;
+    int bytes_to_write;
+    int bytes_to_read;
+    peer_status_t status;
+} PEER;
+
+static void create_peer(PEER *peer, SSL_CTX *ctx)
+{
+    static const int peer_buffer_size = 64 * 1024;
+
+    peer->ssl = SSL_new(ctx);
+    TEST_check(peer->ssl != NULL);
+    peer->write_buf = OPENSSL_zalloc(peer_buffer_size);
+    TEST_check(peer->write_buf != NULL);
+    peer->read_buf = OPENSSL_zalloc(peer_buffer_size);
+    TEST_check(peer->read_buf != NULL);
+    peer->write_buf_len = peer->read_buf_len = peer_buffer_size;
+}
+
+static void peer_free_data(PEER *peer)
+{
+    SSL_free(peer->ssl);
+    OPENSSL_free(peer->write_buf);
+    OPENSSL_free(peer->read_buf);
+}
+
+/*
+ * Note that we could do the handshake transparently under an SSL_write,
+ * but separating the steps is more helpful for debugging test failures.
+ */
+static void do_handshake_step(PEER *peer)
 {
     int ret;
 
-    ret = SSL_do_handshake(ssl);
+    TEST_check(peer->status == PEER_RETRY);
+    ret = SSL_do_handshake(peer->ssl);
 
     if (ret == 1) {
-        return PEER_SUCCESS;
+        peer->status = PEER_SUCCESS;
     } else if (ret == 0) {
-        return PEER_ERROR;
+        peer->status = PEER_ERROR;
     } else {
-        int error = SSL_get_error(ssl, ret);
+        int error = SSL_get_error(peer->ssl, ret);
         /* Memory bios should never block with SSL_ERROR_WANT_WRITE. */
-        if (error == SSL_ERROR_WANT_READ)
-            return PEER_RETRY;
-        else
-            return PEER_ERROR;
+        if (error != SSL_ERROR_WANT_READ)
+            peer->status = PEER_ERROR;
+    }
+}
+
+/*-
+ * Send/receive some application data. The read-write sequence is
+ * Peer A: (R) W - first read will yield no data
+ * Peer B:  R  W
+ * ...
+ * Peer A:  R  W
+ * Peer B:  R  W
+ * Peer A:  R
+ */
+static void do_app_data_step(PEER *peer)
+{
+    int ret = 1, write_bytes;
+
+    TEST_check(peer->status == PEER_RETRY);
+
+    /* We read everything available... */
+    while (ret > 0 && peer->bytes_to_read) {
+        ret = SSL_read(peer->ssl, peer->read_buf, peer->read_buf_len);
+        if (ret > 0) {
+            TEST_check(ret <= peer->bytes_to_read);
+            peer->bytes_to_read -= ret;
+        } else if (ret == 0) {
+            peer->status = PEER_ERROR;
+            return;
+        } else {
+            int error = SSL_get_error(peer->ssl, ret);
+            if (error != SSL_ERROR_WANT_READ) {
+                peer->status = PEER_ERROR;
+                return;
+            } /* Else continue with write. */
+        }
+    }
+
+    /* ... but we only write one write-buffer-full of data. */
+    write_bytes = peer->bytes_to_write < peer->write_buf_len ? peer->bytes_to_write :
+        peer->write_buf_len;
+    if (write_bytes) {
+        ret = SSL_write(peer->ssl, peer->write_buf, write_bytes);
+        if (ret > 0) {
+            /* SSL_write will only succeed with a complete write. */
+            TEST_check(ret == write_bytes);
+            peer->bytes_to_write -= ret;
+        } else {
+            /*
+             * We should perhaps check for SSL_ERROR_WANT_READ/WRITE here
+             * but this doesn't yet occur with current app data sizes.
+             */
+            peer->status = PEER_ERROR;
+            return;
+        }
+    }
+
+    /*
+     * We could simply finish when there was nothing to read, and we have
+     * nothing left to write. But keeping track of the expected number of bytes
+     * to read gives us somewhat better guarantees that all data sent is in fact
+     * received.
+     */
+    if (!peer->bytes_to_write && !peer->bytes_to_read) {
+        peer->status = PEER_SUCCESS;
+    }
+}
+
+static void do_reneg_setup_step(const SSL_TEST_CTX *test_ctx, PEER *peer)
+{
+    int ret;
+    char buf;
+
+    TEST_check(peer->status == PEER_RETRY);
+    TEST_check(test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_RENEG_SERVER
+                || test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_RENEG_CLIENT
+                || test_ctx->handshake_mode
+                   == SSL_TEST_HANDSHAKE_KEY_UPDATE_SERVER
+                || test_ctx->handshake_mode
+                   == SSL_TEST_HANDSHAKE_KEY_UPDATE_CLIENT);
+
+    /* Reset the count of the amount of app data we need to read/write */
+    peer->bytes_to_write = peer->bytes_to_read = test_ctx->app_data_size;
+
+    /* Check if we are the peer that is going to initiate */
+    if ((test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_RENEG_SERVER
+                && SSL_is_server(peer->ssl))
+            || (test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_RENEG_CLIENT
+                && !SSL_is_server(peer->ssl))) {
+        /*
+         * If we already asked for a renegotiation then fall through to the
+         * SSL_read() below.
+         */
+        if (!SSL_renegotiate_pending(peer->ssl)) {
+            /*
+             * If we are the client we will always attempt to resume the
+             * session. The server may or may not resume dependant on the
+             * setting of SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
+             */
+            if (SSL_is_server(peer->ssl)) {
+                ret = SSL_renegotiate(peer->ssl);
+            } else {
+                if (test_ctx->extra.client.reneg_ciphers != NULL) {
+                    if (!SSL_set_cipher_list(peer->ssl,
+                                test_ctx->extra.client.reneg_ciphers)) {
+                        peer->status = PEER_ERROR;
+                        return;
+                    }
+                    ret = SSL_renegotiate(peer->ssl);
+                } else {
+                    ret = SSL_renegotiate_abbreviated(peer->ssl);
+                }
+            }
+            if (!ret) {
+                peer->status = PEER_ERROR;
+                return;
+            }
+            do_handshake_step(peer);
+            /*
+             * If status is PEER_RETRY it means we're waiting on the peer to
+             * continue the handshake. As far as setting up the renegotiation is
+             * concerned that is a success. The next step will continue the
+             * handshake to its conclusion.
+             *
+             * If status is PEER_SUCCESS then we are the server and we have
+             * successfully sent the HelloRequest. We need to continue to wait
+             * until the handshake arrives from the client.
+             */
+            if (peer->status == PEER_RETRY)
+                peer->status = PEER_SUCCESS;
+            else if (peer->status == PEER_SUCCESS)
+                peer->status = PEER_RETRY;
+            return;
+        }
+    } else if (test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_KEY_UPDATE_SERVER
+               || test_ctx->handshake_mode
+                  == SSL_TEST_HANDSHAKE_KEY_UPDATE_CLIENT) {
+        if (SSL_is_server(peer->ssl)
+                != (test_ctx->handshake_mode
+                    == SSL_TEST_HANDSHAKE_KEY_UPDATE_SERVER)) {
+            peer->status = PEER_SUCCESS;
+            return;
+        }
+
+        ret = SSL_key_update(peer->ssl, test_ctx->key_update_type);
+        if (!ret) {
+            peer->status = PEER_ERROR;
+            return;
+        }
+        do_handshake_step(peer);
+        /*
+         * This is a one step handshake. We shouldn't get anything other than
+         * PEER_SUCCESS
+         */
+        if (peer->status != PEER_SUCCESS)
+            peer->status = PEER_ERROR;
+        return;
+    }
+
+    /*
+     * The SSL object is still expecting app data, even though it's going to
+     * get a handshake message. We try to read, and it should fail - after which
+     * we should be in a handshake
+     */
+    ret = SSL_read(peer->ssl, &buf, sizeof(buf));
+    if (ret >= 0) {
+        /*
+         * We're not actually expecting data - we're expecting a reneg to
+         * start
+         */
+        peer->status = PEER_ERROR;
+        return;
+    } else {
+        int error = SSL_get_error(peer->ssl, ret);
+        if (error != SSL_ERROR_WANT_READ) {
+            peer->status = PEER_ERROR;
+            return;
+        }
+        /* If we're not in init yet then we're not done with setup yet */
+        if (!SSL_in_init(peer->ssl))
+            return;
+    }
+
+    peer->status = PEER_SUCCESS;
+}
+
+
+/*
+ * RFC 5246 says:
+ *
+ * Note that as of TLS 1.1,
+ *     failure to properly close a connection no longer requires that a
+ *     session not be resumed.  This is a change from TLS 1.0 to conform
+ *     with widespread implementation practice.
+ *
+ * However,
+ * (a) OpenSSL requires that a connection be shutdown for all protocol versions.
+ * (b) We test lower versions, too.
+ * So we just implement shutdown. We do a full bidirectional shutdown so that we
+ * can compare sent and received close_notify alerts and get some test coverage
+ * for SSL_shutdown as a bonus.
+ */
+static void do_shutdown_step(PEER *peer)
+{
+    int ret;
+
+    TEST_check(peer->status == PEER_RETRY);
+    ret = SSL_shutdown(peer->ssl);
+
+    if (ret == 1) {
+        peer->status = PEER_SUCCESS;
+    } else if (ret < 0) { /* On 0, we retry. */
+        int error = SSL_get_error(peer->ssl, ret);
+
+        if (error != SSL_ERROR_WANT_READ && error != SSL_ERROR_WANT_WRITE)
+            peer->status = PEER_ERROR;
+    }
+}
+
+typedef enum {
+    HANDSHAKE,
+    RENEG_APPLICATION_DATA,
+    RENEG_SETUP,
+    RENEG_HANDSHAKE,
+    APPLICATION_DATA,
+    SHUTDOWN,
+    CONNECTION_DONE
+} connect_phase_t;
+
+static connect_phase_t next_phase(const SSL_TEST_CTX *test_ctx,
+                                  connect_phase_t phase)
+{
+    switch (phase) {
+    case HANDSHAKE:
+        if (test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_RENEG_SERVER
+                || test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_RENEG_CLIENT
+                || test_ctx->handshake_mode
+                   == SSL_TEST_HANDSHAKE_KEY_UPDATE_CLIENT
+                || test_ctx->handshake_mode
+                   == SSL_TEST_HANDSHAKE_KEY_UPDATE_SERVER)
+            return RENEG_APPLICATION_DATA;
+        return APPLICATION_DATA;
+    case RENEG_APPLICATION_DATA:
+        return RENEG_SETUP;
+    case RENEG_SETUP:
+        if (test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_KEY_UPDATE_SERVER
+                || test_ctx->handshake_mode
+                   == SSL_TEST_HANDSHAKE_KEY_UPDATE_CLIENT)
+            return APPLICATION_DATA;
+        return RENEG_HANDSHAKE;
+    case RENEG_HANDSHAKE:
+        return APPLICATION_DATA;
+    case APPLICATION_DATA:
+        return SHUTDOWN;
+    case SHUTDOWN:
+        return CONNECTION_DONE;
+    case CONNECTION_DONE:
+        TEST_check(0);
+        break;
+    }
+    return -1;
+}
+
+static void do_connect_step(const SSL_TEST_CTX *test_ctx, PEER *peer,
+                            connect_phase_t phase)
+{
+    switch (phase) {
+    case HANDSHAKE:
+        do_handshake_step(peer);
+        break;
+    case RENEG_APPLICATION_DATA:
+        do_app_data_step(peer);
+        break;
+    case RENEG_SETUP:
+        do_reneg_setup_step(test_ctx, peer);
+        break;
+    case RENEG_HANDSHAKE:
+        do_handshake_step(peer);
+        break;
+    case APPLICATION_DATA:
+        do_app_data_step(peer);
+        break;
+    case SHUTDOWN:
+        do_shutdown_step(peer);
+        break;
+    case CONNECTION_DONE:
+        TEST_check(0);
+        break;
     }
 }
 
@@ -139,24 +1023,20 @@ static handshake_status_t handshake_status(peer_status_t last_status,
         }
 
     case PEER_RETRY:
-        if (previous_status == PEER_RETRY) {
-            /* Neither peer is done. */
-            return HANDSHAKE_RETRY;
-        } else {
-            /*
-             * Deadlock: second peer is waiting for more input while first
-             * peer thinks they're done (no more input is coming).
-             */
-            return INTERNAL_ERROR;
-        }
+        return HANDSHAKE_RETRY;
+
     case PEER_ERROR:
         switch (previous_status) {
+        case PEER_WAITING:
+            /* The client failed immediately before sending the ClientHello */
+            return client_spoke_last ? CLIENT_ERROR : INTERNAL_ERROR;
         case PEER_SUCCESS:
             /*
              * First peer succeeded but second peer errored.
              * TODO(emilia): we should be able to continue here (with some
              * application data?) to ensure the first peer receives the
              * alert / close_notify.
+             * (No tests currently exercise this branch.)
              */
             return client_spoke_last ? CLIENT_ERROR : SERVER_ERROR;
         case PEER_RETRY:
@@ -171,56 +1051,260 @@ static handshake_status_t handshake_status(peer_status_t last_status,
     return INTERNAL_ERROR;
 }
 
-HANDSHAKE_RESULT do_handshake(SSL_CTX *server_ctx, SSL_CTX *client_ctx,
-                              const SSL_TEST_CTX *test_ctx)
+/* Convert unsigned char buf's that shouldn't contain any NUL-bytes to char. */
+static char *dup_str(const unsigned char *in, size_t len)
+{
+    char *ret;
+
+    if (len == 0)
+        return NULL;
+
+    /* Assert that the string does not contain NUL-bytes. */
+    TEST_check(OPENSSL_strnlen((const char*)(in), len) == len);
+    ret = OPENSSL_strndup((const char*)(in), len);
+    TEST_check(ret != NULL);
+    return ret;
+}
+
+static int pkey_type(EVP_PKEY *pkey)
 {
-    SSL *server, *client;
-    BIO *client_to_server, *server_to_client;
+    int nid = EVP_PKEY_id(pkey);
+
+#ifndef OPENSSL_NO_EC
+    if (nid == EVP_PKEY_EC) {
+        const EC_KEY *ec = EVP_PKEY_get0_EC_KEY(pkey);
+        return EC_GROUP_get_curve_name(EC_KEY_get0_group(ec));
+    }
+#endif
+    return nid;
+}
+
+static int peer_pkey_type(SSL *s)
+{
+    X509 *x = SSL_get_peer_certificate(s);
+
+    if (x != NULL) {
+        int nid = pkey_type(X509_get0_pubkey(x));
+
+        X509_free(x);
+        return nid;
+    }
+    return NID_undef;
+}
+
+#if !defined(OPENSSL_NO_SCTP) && !defined(OPENSSL_NO_SOCK)
+static int set_sock_as_sctp(int sock)
+{
+    /*
+     * For SCTP we have to set various options on the socket prior to
+     * connecting. This is done automatically by BIO_new_dgram_sctp().
+     * We don't actually need the created BIO though so we free it again
+     * immediately.
+     */
+    BIO *tmpbio = BIO_new_dgram_sctp(sock, BIO_NOCLOSE);
+
+    if (tmpbio == NULL)
+        return 0;
+    BIO_free(tmpbio);
+
+    return 1;
+}
+
+static int create_sctp_socks(int *ssock, int *csock)
+{
+    BIO_ADDRINFO *res = NULL;
+    const BIO_ADDRINFO *ai = NULL;
+    int lsock = INVALID_SOCKET, asock = INVALID_SOCKET;
+    int consock = INVALID_SOCKET;
+    int ret = 0;
+    int family = 0;
+
+    if (!BIO_sock_init())
+        return 0;
+
+    /*
+     * Port is 4463. It could be anything. It will fail if it's already being
+     * used for some other SCTP service. It seems unlikely though so we don't
+     * worry about it here.
+     */
+    if (!BIO_lookup_ex(NULL, "4463", BIO_LOOKUP_SERVER, family, SOCK_STREAM,
+                       IPPROTO_SCTP, &res))
+        return 0;
+
+    for (ai = res; ai != NULL; ai = BIO_ADDRINFO_next(ai)) {
+        family = BIO_ADDRINFO_family(ai);
+        lsock = BIO_socket(family, SOCK_STREAM, IPPROTO_SCTP, 0);
+        if (lsock == INVALID_SOCKET) {
+            /* Maybe the kernel doesn't support the socket family, even if
+             * BIO_lookup() added it in the returned result...
+             */
+            continue;
+        }
+
+        if (!set_sock_as_sctp(lsock)
+                || !BIO_listen(lsock, BIO_ADDRINFO_address(ai),
+                               BIO_SOCK_REUSEADDR)) {
+            BIO_closesocket(lsock);
+            lsock = INVALID_SOCKET;
+            continue;
+        }
+
+        /* Success, don't try any more addresses */
+        break;
+    }
+
+    if (lsock == INVALID_SOCKET)
+        goto err;
+
+    BIO_ADDRINFO_free(res);
+    res = NULL;
+
+    if (!BIO_lookup_ex(NULL, "4463", BIO_LOOKUP_CLIENT, family, SOCK_STREAM,
+                        IPPROTO_SCTP, &res))
+        goto err;
+
+    consock = BIO_socket(family, SOCK_STREAM, IPPROTO_SCTP, 0);
+    if (consock == INVALID_SOCKET)
+        goto err;
+
+    if (!set_sock_as_sctp(consock)
+            || !BIO_connect(consock, BIO_ADDRINFO_address(res), 0)
+            || !BIO_socket_nbio(consock, 1))
+        goto err;
+
+    asock = BIO_accept_ex(lsock, NULL, BIO_SOCK_NONBLOCK);
+    if (asock == INVALID_SOCKET)
+        goto err;
+
+    *csock = consock;
+    *ssock = asock;
+    consock = asock = INVALID_SOCKET;
+    ret = 1;
+
+ err:
+    BIO_ADDRINFO_free(res);
+    if (consock != INVALID_SOCKET)
+        BIO_closesocket(consock);
+    if (lsock != INVALID_SOCKET)
+        BIO_closesocket(lsock);
+    if (asock != INVALID_SOCKET)
+        BIO_closesocket(asock);
+    return ret;
+}
+#endif
+
+/*
+ * Note that |extra| points to the correct client/server configuration
+ * within |test_ctx|. When configuring the handshake, general mode settings
+ * are taken from |test_ctx|, and client/server-specific settings should be
+ * taken from |extra|.
+ *
+ * The configuration code should never reach into |test_ctx->extra| or
+ * |test_ctx->resume_extra| directly.
+ *
+ * (We could refactor test mode settings into a substructure. This would result
+ * in cleaner argument passing but would complicate the test configuration
+ * parsing.)
+ */
+static HANDSHAKE_RESULT *do_handshake_internal(
+    SSL_CTX *server_ctx, SSL_CTX *server2_ctx, SSL_CTX *client_ctx,
+    const SSL_TEST_CTX *test_ctx, const SSL_TEST_EXTRA_CONF *extra,
+    SSL_SESSION *session_in, SSL_SESSION **session_out)
+{
+    PEER server, client;
+    BIO *client_to_server = NULL, *server_to_client = NULL;
     HANDSHAKE_EX_DATA server_ex_data, client_ex_data;
-    HANDSHAKE_RESULT ret;
-    int client_turn = 1;
-    peer_status_t client_status = PEER_RETRY, server_status = PEER_RETRY;
+    CTX_DATA client_ctx_data, server_ctx_data, server2_ctx_data;
+    HANDSHAKE_RESULT *ret = HANDSHAKE_RESULT_new();
+    int client_turn = 1, client_turn_count = 0;
+    connect_phase_t phase = HANDSHAKE;
     handshake_status_t status = HANDSHAKE_RETRY;
+    const unsigned char* tick = NULL;
+    size_t tick_len = 0;
+    SSL_SESSION* sess = NULL;
+    const unsigned char *proto = NULL;
+    /* API dictates unsigned int rather than size_t. */
+    unsigned int proto_len = 0;
+    EVP_PKEY *tmp_key;
+    const STACK_OF(X509_NAME) *names;
+    time_t start;
+
+    memset(&server_ctx_data, 0, sizeof(server_ctx_data));
+    memset(&server2_ctx_data, 0, sizeof(server2_ctx_data));
+    memset(&client_ctx_data, 0, sizeof(client_ctx_data));
+    memset(&server, 0, sizeof(server));
+    memset(&client, 0, sizeof(client));
 
-    configure_handshake(server_ctx, client_ctx, test_ctx);
+    configure_handshake_ctx(server_ctx, server2_ctx, client_ctx, test_ctx, extra,
+                            &server_ctx_data, &server2_ctx_data, &client_ctx_data);
 
-    server = SSL_new(server_ctx);
-    client = SSL_new(client_ctx);
-    OPENSSL_assert(server != NULL && client != NULL);
+    /* Setup SSL and buffers; additional configuration happens below. */
+    create_peer(&server, server_ctx);
+    create_peer(&client, client_ctx);
+
+    server.bytes_to_write = client.bytes_to_read = test_ctx->app_data_size;
+    client.bytes_to_write = server.bytes_to_read = test_ctx->app_data_size;
+
+    configure_handshake_ssl(server.ssl, client.ssl, extra);
+    if (session_in != NULL) {
+        /* In case we're testing resumption without tickets. */
+        TEST_check(SSL_CTX_add_session(server_ctx, session_in));
+        TEST_check(SSL_set_session(client.ssl, session_in));
+    }
 
     memset(&server_ex_data, 0, sizeof(server_ex_data));
     memset(&client_ex_data, 0, sizeof(client_ex_data));
-    memset(&ret, 0, sizeof(ret));
-    ret.result = SSL_TEST_INTERNAL_ERROR;
 
-    client_to_server = BIO_new(BIO_s_mem());
-    server_to_client = BIO_new(BIO_s_mem());
+    ret->result = SSL_TEST_INTERNAL_ERROR;
 
-    OPENSSL_assert(client_to_server != NULL && server_to_client != NULL);
+    if (test_ctx->use_sctp) {
+#if !defined(OPENSSL_NO_SCTP) && !defined(OPENSSL_NO_SOCK)
+        int csock, ssock;
+
+        if (create_sctp_socks(&ssock, &csock)) {
+            client_to_server = BIO_new_dgram_sctp(csock, BIO_CLOSE);
+            server_to_client = BIO_new_dgram_sctp(ssock, BIO_CLOSE);
+        }
+#endif
+    } else {
+        client_to_server = BIO_new(BIO_s_mem());
+        server_to_client = BIO_new(BIO_s_mem());
+    }
+
+    TEST_check(client_to_server != NULL);
+    TEST_check(server_to_client != NULL);
 
     /* Non-blocking bio. */
     BIO_set_nbio(client_to_server, 1);
     BIO_set_nbio(server_to_client, 1);
 
-    SSL_set_connect_state(client);
-    SSL_set_accept_state(server);
+    SSL_set_connect_state(client.ssl);
+    SSL_set_accept_state(server.ssl);
 
     /* The bios are now owned by the SSL object. */
-    SSL_set_bio(client, server_to_client, client_to_server);
-    OPENSSL_assert(BIO_up_ref(server_to_client) > 0);
-    OPENSSL_assert(BIO_up_ref(client_to_server) > 0);
-    SSL_set_bio(server, client_to_server, server_to_client);
+    if (test_ctx->use_sctp) {
+        SSL_set_bio(client.ssl, client_to_server, client_to_server);
+        SSL_set_bio(server.ssl, server_to_client, server_to_client);
+    } else {
+        SSL_set_bio(client.ssl, server_to_client, client_to_server);
+        TEST_check(BIO_up_ref(server_to_client) > 0);
+        TEST_check(BIO_up_ref(client_to_server) > 0);
+        SSL_set_bio(server.ssl, client_to_server, server_to_client);
+    }
 
     ex_data_idx = SSL_get_ex_new_index(0, "ex data", NULL, NULL, NULL);
-    OPENSSL_assert(ex_data_idx >= 0);
+    TEST_check(ex_data_idx >= 0);
 
-    OPENSSL_assert(SSL_set_ex_data(server, ex_data_idx,
-                                   &server_ex_data) == 1);
-    OPENSSL_assert(SSL_set_ex_data(client, ex_data_idx,
-                                   &client_ex_data) == 1);
+    TEST_check(SSL_set_ex_data(server.ssl, ex_data_idx, &server_ex_data) == 1);
+    TEST_check(SSL_set_ex_data(client.ssl, ex_data_idx, &client_ex_data) == 1);
 
-    SSL_set_info_callback(server, &info_callback);
-    SSL_set_info_callback(client, &info_callback);
+    SSL_set_info_callback(server.ssl, &info_cb);
+    SSL_set_info_callback(client.ssl, &info_cb);
+
+    client.status = PEER_RETRY;
+    server.status = PEER_WAITING;
+
+    start = time(NULL);
 
     /*
      * Half-duplex handshake loop.
@@ -232,43 +1316,179 @@ HANDSHAKE_RESULT do_handshake(SSL_CTX *server_ctx, SSL_CTX *client_ctx,
      */
     for(;;) {
         if (client_turn) {
-            client_status = do_handshake_step(client);
-            status = handshake_status(client_status, server_status,
+            do_connect_step(test_ctx, &client, phase);
+            status = handshake_status(client.status, server.status,
                                       1 /* client went last */);
+            if (server.status == PEER_WAITING)
+                server.status = PEER_RETRY;
         } else {
-            server_status = do_handshake_step(server);
-            status = handshake_status(server_status, client_status,
+            do_connect_step(test_ctx, &server, phase);
+            status = handshake_status(server.status, client.status,
                                       0 /* server went last */);
         }
 
         switch (status) {
         case HANDSHAKE_SUCCESS:
-            ret.result = SSL_TEST_SUCCESS;
-            goto err;
+            client_turn_count = 0;
+            phase = next_phase(test_ctx, phase);
+            if (phase == CONNECTION_DONE) {
+                ret->result = SSL_TEST_SUCCESS;
+                goto err;
+            } else {
+                client.status = server.status = PEER_RETRY;
+                /*
+                 * For now, client starts each phase. Since each phase is
+                 * started separately, we can later control this more
+                 * precisely, for example, to test client-initiated and
+                 * server-initiated shutdown.
+                 */
+                client_turn = 1;
+                break;
+            }
         case CLIENT_ERROR:
-            ret.result = SSL_TEST_CLIENT_FAIL;
+            ret->result = SSL_TEST_CLIENT_FAIL;
             goto err;
         case SERVER_ERROR:
-            ret.result = SSL_TEST_SERVER_FAIL;
+            ret->result = SSL_TEST_SERVER_FAIL;
             goto err;
         case INTERNAL_ERROR:
-            ret.result = SSL_TEST_INTERNAL_ERROR;
+            ret->result = SSL_TEST_INTERNAL_ERROR;
             goto err;
         case HANDSHAKE_RETRY:
-            /* Continue. */
-            client_turn ^= 1;
+            if (test_ctx->use_sctp) {
+                if (time(NULL) - start > 3) {
+                    /*
+                     * We've waited for too long. Give up.
+                     */
+                    ret->result = SSL_TEST_INTERNAL_ERROR;
+                    goto err;
+                }
+                /*
+                 * With "real" sockets we only swap to processing the peer
+                 * if they are expecting to retry. Otherwise we just retry the
+                 * same endpoint again.
+                 */
+                if ((client_turn && server.status == PEER_RETRY)
+                        || (!client_turn && client.status == PEER_RETRY))
+                    client_turn ^= 1;
+            } else {
+                if (client_turn_count++ >= 2000) {
+                    /*
+                     * At this point, there's been so many PEER_RETRY in a row
+                     * that it's likely both sides are stuck waiting for a read.
+                     * It's time to give up.
+                     */
+                    ret->result = SSL_TEST_INTERNAL_ERROR;
+                    goto err;
+                }
+
+                /* Continue. */
+                client_turn ^= 1;
+            }
             break;
         }
     }
  err:
-    ret.server_alert_sent = server_ex_data.alert_sent;
-    ret.server_alert_received = client_ex_data.alert_received;
-    ret.client_alert_sent = client_ex_data.alert_sent;
-    ret.client_alert_received = server_ex_data.alert_received;
-    ret.server_protocol = SSL_version(server);
-    ret.client_protocol = SSL_version(client);
-
-    SSL_free(server);
-    SSL_free(client);
+    ret->server_alert_sent = server_ex_data.alert_sent;
+    ret->server_num_fatal_alerts_sent = server_ex_data.num_fatal_alerts_sent;
+    ret->server_alert_received = client_ex_data.alert_received;
+    ret->client_alert_sent = client_ex_data.alert_sent;
+    ret->client_num_fatal_alerts_sent = client_ex_data.num_fatal_alerts_sent;
+    ret->client_alert_received = server_ex_data.alert_received;
+    ret->server_protocol = SSL_version(server.ssl);
+    ret->client_protocol = SSL_version(client.ssl);
+    ret->servername = server_ex_data.servername;
+    if ((sess = SSL_get0_session(client.ssl)) != NULL)
+        SSL_SESSION_get0_ticket(sess, &tick, &tick_len);
+    if (tick == NULL || tick_len == 0)
+        ret->session_ticket = SSL_TEST_SESSION_TICKET_NO;
+    else
+        ret->session_ticket = SSL_TEST_SESSION_TICKET_YES;
+    ret->compression = (SSL_get_current_compression(client.ssl) == NULL)
+                       ? SSL_TEST_COMPRESSION_NO
+                       : SSL_TEST_COMPRESSION_YES;
+    ret->session_ticket_do_not_call = server_ex_data.session_ticket_do_not_call;
+
+#ifndef OPENSSL_NO_NEXTPROTONEG
+    SSL_get0_next_proto_negotiated(client.ssl, &proto, &proto_len);
+    ret->client_npn_negotiated = dup_str(proto, proto_len);
+
+    SSL_get0_next_proto_negotiated(server.ssl, &proto, &proto_len);
+    ret->server_npn_negotiated = dup_str(proto, proto_len);
+#endif
+
+    SSL_get0_alpn_selected(client.ssl, &proto, &proto_len);
+    ret->client_alpn_negotiated = dup_str(proto, proto_len);
+
+    SSL_get0_alpn_selected(server.ssl, &proto, &proto_len);
+    ret->server_alpn_negotiated = dup_str(proto, proto_len);
+
+    ret->client_resumed = SSL_session_reused(client.ssl);
+    ret->server_resumed = SSL_session_reused(server.ssl);
+
+    if (session_out != NULL)
+        *session_out = SSL_get1_session(client.ssl);
+
+    if (SSL_get_server_tmp_key(client.ssl, &tmp_key)) {
+        ret->tmp_key_type = pkey_type(tmp_key);
+        EVP_PKEY_free(tmp_key);
+    }
+
+    SSL_get_peer_signature_nid(client.ssl, &ret->server_sign_hash);
+    SSL_get_peer_signature_nid(server.ssl, &ret->client_sign_hash);
+
+    SSL_get_peer_signature_type_nid(client.ssl, &ret->server_sign_type);
+    SSL_get_peer_signature_type_nid(server.ssl, &ret->client_sign_type);
+
+    names = SSL_get0_peer_CA_list(client.ssl);
+    if (names == NULL)
+        ret->client_ca_names = NULL;
+    else
+        ret->client_ca_names = SSL_dup_CA_list(names);
+
+    names = SSL_get0_peer_CA_list(server.ssl);
+    if (names == NULL)
+        ret->server_ca_names = NULL;
+    else
+        ret->server_ca_names = SSL_dup_CA_list(names);
+
+    ret->server_cert_type = peer_pkey_type(client.ssl);
+    ret->client_cert_type = peer_pkey_type(server.ssl);
+
+    ctx_data_free_data(&server_ctx_data);
+    ctx_data_free_data(&server2_ctx_data);
+    ctx_data_free_data(&client_ctx_data);
+
+    peer_free_data(&server);
+    peer_free_data(&client);
     return ret;
 }
+
+HANDSHAKE_RESULT *do_handshake(SSL_CTX *server_ctx, SSL_CTX *server2_ctx,
+                               SSL_CTX *client_ctx, SSL_CTX *resume_server_ctx,
+                               SSL_CTX *resume_client_ctx,
+                               const SSL_TEST_CTX *test_ctx)
+{
+    HANDSHAKE_RESULT *result;
+    SSL_SESSION *session = NULL;
+
+    result = do_handshake_internal(server_ctx, server2_ctx, client_ctx,
+                                   test_ctx, &test_ctx->extra,
+                                   NULL, &session);
+    if (test_ctx->handshake_mode != SSL_TEST_HANDSHAKE_RESUME)
+        goto end;
+
+    if (result->result != SSL_TEST_SUCCESS) {
+        result->result = SSL_TEST_FIRST_HANDSHAKE_FAILED;
+        goto end;
+    }
+
+    HANDSHAKE_RESULT_free(result);
+    /* We don't support SNI on second handshake yet, so server2_ctx is NULL. */
+    result = do_handshake_internal(resume_server_ctx, NULL, resume_client_ctx,
+                                   test_ctx, &test_ctx->resume_extra,
+                                   session, NULL);
+ end:
+    SSL_SESSION_free(session);
+    return result;
+}