commit d4504fe5792b2dcf8ae6ef35634f1494e72d109b
author Matt Caswell <matt@openssl.org> Fri Jul 14 14:50:48 2017 +0100
committer Matt Caswell <matt@openssl.org> Tue Jul 18 16:51:58 2017 +0100
tree 7b51694b056efe6d8c86b92b6677b6eecf83372a
parent 1e3f62a3823f7e3db9d403f724fd9d66f5b04cf8

Fix early_data with an HRR

early_data is not allowed after an HRR. We failed to handle that
correctly.

Reviewed-by: Ben Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/3933)

ssl/statem/extensions_srvr.c

diff --git a/ssl/statem/extensions_srvr.c b/ssl/statem/extensions_srvr.c
index 7f30ac7..9fe58a7 100644
--- a/ssl/statem/extensions_srvr.c
+++ b/ssl/statem/extensions_srvr.c
@@ -678,6 +678,11 @@
         return 0;
     }
 
+    if (s->hello_retry_request) {
+        *al = SSL_AD_ILLEGAL_PARAMETER;
+        return 0;
+    }
+
     return 1;
 }
 

ssl/statem/statem.c

diff --git a/ssl/statem/statem.c b/ssl/statem/statem.c
index 9eab8ce..e5a50c4 100644
--- a/ssl/statem/statem.c
+++ b/ssl/statem/statem.c
@@ -157,13 +157,8 @@
     if (s->ext.early_data != SSL_EARLY_DATA_REJECTED)
         return 0;
 
-    if (s->hello_retry_request) {
-        if (s->statem.hand_state != TLS_ST_SW_HELLO_RETRY_REQUEST)
-            return 0;
-    } else {
-        if (!s->server || s->statem.hand_state != TLS_ST_EARLY_DATA)
-            return 0;
-    }
+    if (!s->server || s->statem.hand_state != TLS_ST_EARLY_DATA)
+        return 0;
 
     return 1;
 }

ssl/statem/statem_clnt.c

diff --git a/ssl/statem/statem_clnt.c b/ssl/statem/statem_clnt.c
index 55ac4dd..ed9bd5c 100644
--- a/ssl/statem/statem_clnt.c
+++ b/ssl/statem/statem_clnt.c
@@ -1571,6 +1571,13 @@
 
     s->hello_retry_request = 1;
 
+    /*
+     * If we were sending early_data then the enc_write_ctx is now invalid and
+     * should not be used.
+     */
+    EVP_CIPHER_CTX_free(s->enc_write_ctx);
+    s->enc_write_ctx = NULL;
+
     /* This will fail if it doesn't choose TLSv1.3+ */
     errorcode = ssl_choose_client_version(s, sversion, 0, &al);
     if (errorcode != 0) {

ssl/statem/statem_srvr.c

diff --git a/ssl/statem/statem_srvr.c b/ssl/statem/statem_srvr.c
index f3f54d4..9d3c387 100644
--- a/ssl/statem/statem_srvr.c
+++ b/ssl/statem/statem_srvr.c
@@ -48,15 +48,14 @@
     default:
         break;
 
-    case TLS_ST_SW_HELLO_RETRY_REQUEST:
-        if (mt == SSL3_MT_CLIENT_HELLO) {
-            st->hand_state = TLS_ST_SR_CLNT_HELLO;
-            return 1;
-        }
-        break;
-
     case TLS_ST_EARLY_DATA:
-        if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED) {
+        if (s->hello_retry_request) {
+            if (mt == SSL3_MT_CLIENT_HELLO) {
+                st->hand_state = TLS_ST_SR_CLNT_HELLO;
+                return 1;
+            }
+            break;
+        } else if (s->ext.early_data == SSL_EARLY_DATA_ACCEPTED) {
             if (mt == SSL3_MT_END_OF_EARLY_DATA) {
                 st->hand_state = TLS_ST_SR_END_OF_EARLY_DATA;
                 return 1;
@@ -397,7 +396,8 @@
         return WRITE_TRAN_CONTINUE;
 
     case TLS_ST_SW_HELLO_RETRY_REQUEST:
-        return WRITE_TRAN_FINISHED;
+        st->hand_state = TLS_ST_EARLY_DATA;
+        return WRITE_TRAN_CONTINUE;
 
     case TLS_ST_SW_SRVR_HELLO:
         st->hand_state = TLS_ST_SW_ENCRYPTED_EXTENSIONS;