From b90db257a1948b2c6ed426994416d4bad8bf88eb Mon Sep 17 00:00:00 2001
From: David Cooper <david.cooper@nist.gov>
Date: Fri, 15 Apr 2022 08:10:05 -0400
Subject: [PATCH] Update PROTOS_OFFERED

In some rare cases, a connection to the server will fail with tls_sockets() but not with $OPENSSL. This can cause determine_optimal_sockets_params() to call add_proto_offered() to indicate that the protocol is not supported, and then determine_optimal_proto() to later call add_proto_offered() to indicate that it is supported. However, PROTOS_OFFERED does not get changed, since add_proto_offered() only modifies PROTOS_OFFERED if the protocol is not already listed.

This commit fixes the problem by allowing add_proto_offered() to change an entry for a protocol from "no" to "yes".

If determine_optimal_proto() happens to connect to the server using TLS 1.2, then this commit will set TLS12_CIPHER_OFFERED to the cipher from that connection, if TLS12_CIPHER_OFFERED was not set in determine_optimal_sockets_params(). This will allow run_protocols()'s test of a TLS 1.3 ClientHello to work better, if the problem is that no cipher supported by the server is included in TLS12_CIPHER or TLS12_CIPHER_2ND_TRY.
---
 testssl.sh | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/testssl.sh b/testssl.sh
index 173943c..e2670fb 100755
--- a/testssl.sh
+++ b/testssl.sh
@@ -5174,10 +5174,11 @@ run_prototest_openssl() {
 # arg2: available (yes) or not (no)
 add_proto_offered() {
      # the ":" is mandatory here (and @ other places), otherwise e.g. tls1 will match tls1_2
-     if [[ "$PROTOS_OFFERED" =~ $1: ]]; then
-          # we got that protocol already
-          :
-     else
+     if [[ "$2" == yes ]] && [[ "$PROTOS_OFFERED" =~ $1:no ]]; then
+          # In rare cases, a protocol may be marked as not available even though it is
+          # (e.g., the connection fails with tls_sockets() but succeeds with $OPENSSL.
+          PROTOS_OFFERED="${PROTOS_OFFERED/$1:no/$1:$2}"
+     elif [[ ! "$PROTOS_OFFERED" =~ $1: ]]; then
           PROTOS_OFFERED+="${1}:$2 "
      fi
 }
@@ -21341,6 +21342,10 @@ determine_optimal_proto() {
         [[ "$(has_server_protocol "tls1_1")" -ne 0 ]] && [[ "$(has_server_protocol "tls1")" -ne 0 ]] &&
         [[ "$(has_server_protocol "ssl3")" -ne 0 ]]; then
           TLS13_ONLY=true
+     elif [[ -z "$TLS12_CIPHER_OFFERED" ]] && [[ "$(has_server_protocol "tls1_2")" -eq 0 ]] && [[ "$(get_protocol $TMPFILE)" == TLSv1.2 ]]; then
+          TLS12_CIPHER_OFFERED="$(get_cipher $TMPFILE)"
+          TLS12_CIPHER_OFFERED="$(openssl2hexcode "$TLS12_CIPHER_OFFERED")"
+          [[ ${#TLS12_CIPHER_OFFERED} -eq 9 ]] && TLS12_CIPHER_OFFERED="${TLS12_CIPHER_OFFERED:2:2},${TLS12_CIPHER_OFFERED:7:2}" || TLS12_CIPHER_OFFERED=""
      fi
 
      if [[ "$optimal_proto" == -ssl2 ]]; then