show-tls shows mixed TLS 1.3 and TLS 1.2 ciphers. The ciphersuites
are only valid in tls-cipher or tls-ciphersuites. So this confusing and
not really helpful.

This patch modifies show-tls to show separate lists for TLS 1.2 and
TLS 1.3.
---
 src/openvpn/init.c        |  1 +
 src/openvpn/ssl_backend.h |  1 +
 src/openvpn/ssl_mbedtls.c |  2 +
 src/openvpn/ssl_openssl.c | 79 ++++++++++++++++++++++++++++++---------
 4 files changed, 65 insertions(+), 18 deletions(-)

diff --git a/src/openvpn/init.c b/src/openvpn/init.c
index b2ab2a60..ff863cf8 100644
--- a/src/openvpn/init.c
+++ b/src/openvpn/init.c
@@ -1040,6 +1040,7 @@ print_openssl_info(const struct options *options)
         if (options->show_tls_ciphers)
         {
             show_available_tls_ciphers(options->cipher_list,
+                                       options->cipher_list_tls13,
                                        options->tls_cert_profile);
         }
         if (options->show_curves)
diff --git a/src/openvpn/ssl_backend.h b/src/openvpn/ssl_backend.h
index 0995bb4c..42934230 100644
--- a/src/openvpn/ssl_backend.h
+++ b/src/openvpn/ssl_backend.h
@@ -525,6 +525,7 @@ void print_details(struct key_state_ssl *ks_ssl, const char 
*prefix);
  */
 void
 show_available_tls_ciphers(const char *cipher_list,
+                           const char *cipher_list_tls13,
                            const char *tls_cert_profile);
 
 /*
diff --git a/src/openvpn/ssl_mbedtls.c b/src/openvpn/ssl_mbedtls.c
index f23cd30a..2c6e54b3 100644
--- a/src/openvpn/ssl_mbedtls.c
+++ b/src/openvpn/ssl_mbedtls.c
@@ -1341,8 +1341,10 @@ print_details(struct key_state_ssl *ks_ssl, const char 
*prefix)
 
 void
 show_available_tls_ciphers(const char *cipher_list,
+                           const char *cipher_list_tls13,
                            const char *tls_cert_profile)
 {
+    (void) cipher_list_tls13; // Avoid unused warning
     struct tls_root_ctx tls_ctx;
     const int *ciphers = mbedtls_ssl_list_ciphersuites();
 
diff --git a/src/openvpn/ssl_openssl.c b/src/openvpn/ssl_openssl.c
index e3f02d05..044070fe 100644
--- a/src/openvpn/ssl_openssl.c
+++ b/src/openvpn/ssl_openssl.c
@@ -60,6 +60,7 @@
 #include <openssl/pkcs12.h>
 #include <openssl/rsa.h>
 #include <openssl/x509.h>
+#include <openssl/ssl.h>
 #ifndef OPENSSL_NO_EC
 #include <openssl/ec.h>
 #endif
@@ -1978,15 +1979,12 @@ print_details(struct key_state_ssl *ks_ssl, const char 
*prefix)
     msg(D_HANDSHAKE, "%s%s", s1, s2);
 }
 
-void
-show_available_tls_ciphers(const char *cipher_list,
-                           const char *tls_cert_profile)
+static void
+show_available_tls_ciphers_list(const char *cipher_list,
+                           const char *tls_cert_profile,
+                           const bool tls13)
 {
     struct tls_root_ctx tls_ctx;
-    SSL *ssl;
-    const char *cipher_name;
-    const tls_cipher_name_pair *pair;
-    int priority = 0;
 
     tls_ctx.ctx = SSL_CTX_new(SSLv23_method());
     if (!tls_ctx.ctx)
@@ -1994,22 +1992,44 @@ show_available_tls_ciphers(const char *cipher_list,
         crypto_msg(M_FATAL, "Cannot create SSL_CTX object");
     }
 
-    ssl = SSL_new(tls_ctx.ctx);
-    if (!ssl)
+#if (OPENSSL_VERSION_NUMBER >= 0x1010100fL)
+    if (tls13)
     {
-        crypto_msg(M_FATAL, "Cannot create SSL object");
+        SSL_CTX_set_min_proto_version(tls_ctx.ctx, TLS1_3_VERSION);
+    }
+    else
+#endif
+    {
+        SSL_CTX_set_max_proto_version(tls_ctx.ctx, TLS1_2_VERSION);
     }
 
     tls_ctx_set_cert_profile(&tls_ctx, tls_cert_profile);
     tls_ctx_restrict_ciphers(&tls_ctx, cipher_list);
 
-    printf("Available TLS Ciphers,\n");
-    printf("listed in order of preference:\n\n");
-    while ((cipher_name = SSL_get_cipher_list(ssl, priority++)))
+    SSL *ssl = SSL_new(tls_ctx.ctx);
+    if (!ssl)
     {
-        pair = tls_get_cipher_name_pair(cipher_name, strlen(cipher_name));
+        crypto_msg(M_FATAL, "Cannot create SSL object");
+    }
+
+#if (OPENSSL_VERSION_NUMBER < 0x1010000fL)
+    STACK_OF(SSL_CIPHER)* sk = SSL_get_ciphers(ssl);
+#else
+    STACK_OF(SSL_CIPHER)* sk = SSL_get1_supported_ciphers(ssl);
+#endif
+    for (int i=0;i < sk_SSL_CIPHER_num(sk);i++)
+    {
+        const SSL_CIPHER* c = sk_SSL_CIPHER_value(sk, i);
+
+        const char* cipher_name = SSL_CIPHER_get_name(c);
+
+        const tls_cipher_name_pair *pair = 
tls_get_cipher_name_pair(cipher_name, strlen(cipher_name));
 
-        if (NULL == pair)
+        if (tls13)
+        {
+              printf("%s\n", cipher_name);
+        }
+        else if (NULL == pair)
         {
             /* No translation found, print warning */
             printf("%s (No IANA name known to OpenVPN, use OpenSSL name.)\n", 
cipher_name);
@@ -2018,14 +2038,37 @@ show_available_tls_ciphers(const char *cipher_list,
         {
             printf("%s\n", pair->iana_name);
         }
-
     }
-    printf("\n" SHOW_TLS_CIPHER_LIST_WARNING);
-
+#if (OPENSSL_VERSION_NUMBER >= 0x1010000fL)
+    sk_SSL_CIPHER_free(sk);
+#endif
     SSL_free(ssl);
     SSL_CTX_free(tls_ctx.ctx);
 }
 
+
+
+void
+show_available_tls_ciphers(const char *cipher_list,
+                           const char *cipher_list_tls13,
+                           const char *tls_cert_profile)
+{
+    printf("Available TLS Ciphers,\n");
+    printf("listed in order of preference:\n");
+
+#if (OPENSSL_VERSION_NUMBER >= 0x1010100fL)
+    printf("\nFor TLS 1.3 and newer (--tls-ciphersuite):\n\n");
+    show_available_tls_ciphers_list(cipher_list_tls13, tls_cert_profile, true);
+#else
+    (void) cipher_list_tls13;  /* Avoid unused warning */
+#endif
+
+    printf("\nFor TLS 1.2 and older (--tls-cipher):\n\n");
+    show_available_tls_ciphers_list(cipher_list, tls_cert_profile, false);
+
+    printf("\n" SHOW_TLS_CIPHER_LIST_WARNING);
+}
+
 /*
  * Show the Elliptic curves that are available for us to use
  * in the OpenSSL library.
-- 
2.19.0



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