Provide an SSLfatal() macro
[openssl.git] / ssl / statem / statem.c
index f39a52946304ed5c5f1bc148ff7368ff24d5f56f..c9ac4fb571831485ee4680b37e7c0f14573dac91 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2015-2017 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -7,6 +7,7 @@
  * https://www.openssl.org/source/license.html
  */
 
+#include "internal/cryptlib.h"
 #include <openssl/rand.h>
 #include "../ssl_locl.h"
 #include "statem_locl.h"
@@ -105,17 +106,28 @@ void ossl_statem_clear(SSL *s)
  */
 void ossl_statem_set_renegotiate(SSL *s)
 {
-    s->statem.state = MSG_FLOW_RENEGOTIATE;
     s->statem.in_init = 1;
+    s->statem.request_state = TLS_ST_SW_HELLO_REQ;
 }
 
 /*
- * Put the state machine into an error state. This is a permanent error for
- * the current connection.
+ * Put the state machine into an error state and send an alert if appropriate.
+ * This is a permanent error for the current connection.
  */
-void ossl_statem_set_error(SSL *s)
+void ossl_statem_fatal(SSL *s, int al, int func, int reason, const char *file,
+                       int line)
 {
+    s->statem.in_init = 1;
     s->statem.state = MSG_FLOW_ERROR;
+    ERR_put_error(ERR_LIB_SSL, func, reason, file, line);
+    if (s->statem.hand_state != TLS_ST_BEFORE
+            && s->statem.hand_state != TLS_ST_CW_CLNT_HELLO) {
+        /*
+         * We only send an alert if we've got as far as actually sending or
+         * receiving a message.
+         */
+        ssl3_send_alert(s, SSL3_AL_FATAL, al);
+    }
 }
 
 /*
@@ -151,6 +163,60 @@ void ossl_statem_set_in_handshake(SSL *s, int inhand)
         s->statem.in_handshake--;
 }
 
+/* Are we in a sensible state to skip over unreadable early data? */
+int ossl_statem_skip_early_data(SSL *s)
+{
+    if (s->ext.early_data != SSL_EARLY_DATA_REJECTED)
+        return 0;
+
+    if (!s->server || s->statem.hand_state != TLS_ST_EARLY_DATA)
+        return 0;
+
+    return 1;
+}
+
+/*
+ * Called when we are in SSL_read*(), SSL_write*(), or SSL_accept()
+ * /SSL_connect()/SSL_do_handshake(). Used to test whether we are in an early
+ * data state and whether we should attempt to move the handshake on if so.
+ * |sending| is 1 if we are attempting to send data (SSL_write*()), 0 if we are
+ * attempting to read data (SSL_read*()), or -1 if we are in SSL_do_handshake()
+ * or similar.
+ */
+void ossl_statem_check_finish_init(SSL *s, int sending)
+{
+    if (sending == -1) {
+        if (s->statem.hand_state == TLS_ST_PENDING_EARLY_DATA_END
+                || s->statem.hand_state == TLS_ST_EARLY_DATA) {
+            ossl_statem_set_in_init(s, 1);
+            if (s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY) {
+                /*
+                 * SSL_connect() or SSL_do_handshake() has been called directly.
+                 * We don't allow any more writing of early data.
+                 */
+                s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
+            }
+        }
+    } else if (!s->server) {
+        if ((sending && (s->statem.hand_state == TLS_ST_PENDING_EARLY_DATA_END
+                      || s->statem.hand_state == TLS_ST_EARLY_DATA)
+                  && s->early_data_state != SSL_EARLY_DATA_WRITING)
+                || (!sending && s->statem.hand_state == TLS_ST_EARLY_DATA)) {
+            ossl_statem_set_in_init(s, 1);
+            /*
+             * SSL_write() has been called directly. We don't allow any more
+             * writing of early data.
+             */
+            if (sending && s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY)
+                s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
+        }
+    } else {
+        if (s->early_data_state == SSL_EARLY_DATA_FINISHED_READING
+                && s->statem.hand_state == TLS_ST_EARLY_DATA)
+            ossl_statem_set_in_init(s, 1);
+    }
+}
+
 void ossl_statem_set_hello_verify_done(SSL *s)
 {
     s->statem.state = MSG_FLOW_UNINITED;
@@ -189,10 +255,10 @@ static info_cb get_callback(SSL *s)
 
 /*
  * The main message flow state machine. We start in the MSG_FLOW_UNINITED or
- * MSG_FLOW_RENEGOTIATE state and finish in MSG_FLOW_FINISHED. Valid states and
+ * MSG_FLOW_FINISHED state and finish in MSG_FLOW_FINISHED. Valid states and
  * transitions are as follows:
  *
- * MSG_FLOW_UNINITED     MSG_FLOW_RENEGOTIATE
+ * MSG_FLOW_UNINITED     MSG_FLOW_FINISHED
  *        |                       |
  *        +-----------------------+
  *        v
@@ -218,7 +284,6 @@ static info_cb get_callback(SSL *s)
 static int state_machine(SSL *s, int server)
 {
     BUF_MEM *buf = NULL;
-    unsigned long Time = (unsigned long)time(NULL);
     void (*cb) (const SSL *ssl, int type, int val) = NULL;
     OSSL_STATEM *st = &s->statem;
     int ret = -1;
@@ -229,7 +294,6 @@ static int state_machine(SSL *s, int server)
         return -1;
     }
 
-    RAND_add(&Time, sizeof(Time), 0);
     ERR_clear_error();
     clear_sys_error();
 
@@ -241,10 +305,10 @@ static int state_machine(SSL *s, int server)
             return -1;
     }
 #ifndef OPENSSL_NO_SCTP
-    if (SSL_IS_DTLS(s)) {
+    if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
         /*
          * Notify SCTP BIO socket to enter handshake mode and prevent stream
-         * identifier other than 0. Will be ignored if no SCTP is used.
+         * identifier other than 0.
          */
         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
                  st->in_handshake, NULL);
@@ -252,16 +316,11 @@ static int state_machine(SSL *s, int server)
 #endif
 
     /* Initialise state machine */
-
-    if (st->state == MSG_FLOW_RENEGOTIATE) {
-        s->renegotiate = 1;
-        if (!server)
-            s->ctx->stats.sess_connect_renegotiate++;
-    }
-
-    if (st->state == MSG_FLOW_UNINITED || st->state == MSG_FLOW_RENEGOTIATE) {
+    if (st->state == MSG_FLOW_UNINITED
+            || st->state == MSG_FLOW_FINISHED) {
         if (st->state == MSG_FLOW_UNINITED) {
             st->hand_state = TLS_ST_BEFORE;
+            st->request_state = TLS_ST_BEFORE;
         }
 
         s->server = server;
@@ -318,53 +377,17 @@ static int state_machine(SSL *s, int server)
                 goto end;
             }
 
-        if (!server || st->state != MSG_FLOW_RENEGOTIATE) {
-            if (!ssl3_init_finished_mac(s)) {
-                ossl_statem_set_error(s);
+        if ((SSL_in_before(s))
+                || s->renegotiate) {
+            if (!tls_setup_handshake(s))
                 goto end;
-            }
-        }
 
-        if (server) {
-            if (st->state != MSG_FLOW_RENEGOTIATE) {
-                s->ctx->stats.sess_accept++;
-            } else if (!s->s3->send_connection_binding &&
-                       !(s->options &
-                         SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) {
-                /*
-                 * Server attempting to renegotiate with client that doesn't
-                 * support secure renegotiation.
-                 */
-                SSLerr(SSL_F_STATE_MACHINE,
-                       SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
-                ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
-                ossl_statem_set_error(s);
-                goto end;
-            } else {
-                /*
-                 * st->state == MSG_FLOW_RENEGOTIATE, we will just send a
-                 * HelloRequest
-                 */
-                s->ctx->stats.sess_accept_renegotiate++;
-            }
-        } else {
-            s->ctx->stats.sess_connect++;
-
-            /* mark client_random uninitialized */
-            memset(s->s3->client_random, 0, sizeof(s->s3->client_random));
-            s->hit = 0;
-
-            s->s3->tmp.cert_request = 0;
-            s->s3->tmp.cert_req = 0;
-
-            if (SSL_IS_DTLS(s)) {
-                st->use_timer = 1;
-            }
+            if (SSL_IS_FIRST_HANDSHAKE(s))
+                st->read_state_first_init = 1;
         }
 
         st->state = MSG_FLOW_WRITING;
         init_write_state_machine(s);
-        st->read_state_first_init = 1;
     }
 
     while (st->state != MSG_FLOW_FINISHED) {
@@ -390,22 +413,22 @@ static int state_machine(SSL *s, int server)
             }
         } else {
             /* Error */
-            ossl_statem_set_error(s);
+            SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_STATE_MACHINE,
+                     ERR_R_INTERNAL_ERROR);
             goto end;
         }
     }
 
-    st->state = MSG_FLOW_UNINITED;
     ret = 1;
 
  end:
     st->in_handshake--;
 
 #ifndef OPENSSL_NO_SCTP
-    if (SSL_IS_DTLS(s)) {
+    if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
         /*
          * Notify SCTP BIO socket to leave handshake mode and allow stream
-         * identifier other than 0. Will be ignored if no SCTP is used.
+         * identifier other than 0.
          */
         BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
                  st->in_handshake, NULL);
@@ -605,6 +628,7 @@ static SUB_STATE_RETURN read_state_machine(SSL *s)
             case WORK_ERROR:
             case WORK_MORE_A:
             case WORK_MORE_B:
+            case WORK_MORE_C:
                 return SUB_STATE_ERROR;
 
             case WORK_FINISHED_CONTINUE:
@@ -747,6 +771,7 @@ static SUB_STATE_RETURN write_state_machine(SSL *s)
             case WORK_ERROR:
             case WORK_MORE_A:
             case WORK_MORE_B:
+            case WORK_MORE_C:
                 return SUB_STATE_ERROR;
 
             case WORK_FINISHED_CONTINUE:
@@ -756,8 +781,17 @@ static SUB_STATE_RETURN write_state_machine(SSL *s)
             case WORK_FINISHED_STOP:
                 return SUB_STATE_END_HANDSHAKE;
             }
+            if (!get_construct_message_f(s, &pkt, &confunc, &mt)) {
+                ossl_statem_set_error(s);
+                return SUB_STATE_ERROR;
+            }
+            if (mt == SSL3_MT_DUMMY) {
+                /* Skip construction and sending. This isn't a "real" state */
+                st->write_state = WRITE_STATE_POST_WORK;
+                st->write_state_work = WORK_MORE_A;
+                break;
+            }
             if (!WPACKET_init(&pkt, s->init_buf)
-                    || !get_construct_message_f(s, &pkt, &confunc, &mt)
                     || !ssl_set_handshake_header(s, &pkt, mt)
                     || (confunc != NULL && !confunc(s, &pkt))
                     || !ssl_close_construct_packet(s, &pkt, mt)
@@ -786,6 +820,7 @@ static SUB_STATE_RETURN write_state_machine(SSL *s)
             case WORK_ERROR:
             case WORK_MORE_A:
             case WORK_MORE_B:
+            case WORK_MORE_C:
                 return SUB_STATE_ERROR;
 
             case WORK_FINISHED_CONTINUE:
@@ -819,7 +854,7 @@ int statem_flush(SSL *s)
 
 /*
  * Called by the record layer to determine whether application data is
- * allowed to be sent in the current handshake state or not.
+ * allowed to be received in the current handshake state or not.
  *
  * Return values are:
  *   1: Yes (application data allowed)
@@ -829,7 +864,7 @@ int ossl_statem_app_data_allowed(SSL *s)
 {
     OSSL_STATEM *st = &s->statem;
 
-    if (st->state == MSG_FLOW_UNINITED || st->state == MSG_FLOW_RENEGOTIATE)
+    if (st->state == MSG_FLOW_UNINITED)
         return 0;
 
     if (!s->s3->in_read_app_data || (s->s3->total_renegotiations == 0))
@@ -854,26 +889,3 @@ int ossl_statem_app_data_allowed(SSL *s)
 
     return 0;
 }
-
-#ifndef OPENSSL_NO_SCTP
-/*
- * Set flag used by SCTP to determine whether we are in the read sock state
- */
-void ossl_statem_set_sctp_read_sock(SSL *s, int read_sock)
-{
-    s->statem.in_sctp_read_sock = read_sock;
-}
-
-/*
- * Called by the record layer to determine whether we are in the read sock
- * state or not.
- *
- * Return values are:
- *   1: Yes (we are in the read sock state)
- *   0: No (we are not in the read sock state)
- */
-int ossl_statem_in_sctp_read_sock(SSL *s)
-{
-    return s->statem.in_sctp_read_sock;
-}
-#endif