Stop requiring TLS 1.3 for ECDSA so curl HTTP/1.1 can handshake, and put the curl origin back on RSA TLS 1.2.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: apeters1971

src/XrdTls/XrdTlsContext.cc

@@ -464,36 +464,20 @@ bool PkeyIsRsa(EVP_PKEY *pkey)
           ;
 }
 
-bool PkeyIsEc(EVP_PKEY *pkey)
-{
-   if (!pkey)
-      return false;
-#if OPENSSL_VERSION_NUMBER >= 0x30000000L
-   if (EVP_PKEY_is_a(pkey, "EC"))
-      return true;
-#endif
-   return EVP_PKEY_base_id(pkey) == EVP_PKEY_EC;
-}
-
 // RHEL crypto-policies omit rsa_pss_rsae_* from the client's
 // signature_algorithms, so TLS 1.3 with an RSA host cert fails
 // tls_choose_sigalg. SSL_CTX_set1_sigalgs* aborts after HTTPS plugin
-// init. Cap RSA at TLS 1.2 (rsa_pkcs1). ECDSA hosts require TLS 1.3
-// so curl --http1.1 cannot fall back to a TLS 1.2 cipher mismatch.
+// init. Cap RSA at TLS 1.2 (rsa_pkcs1). Do not raise the floor for
+// ECDSA: curl --http1.1 on this platform still sends TLS 1.2.
 void LimitServerProtoByKey(SSL_CTX *ctx)
 {
 #ifdef TLS1_2_VERSION
-   EVP_PKEY *pkey = ServerPkey(ctx);
-   if (PkeyIsRsa(pkey)) {
+   if (PkeyIsRsa(ServerPkey(ctx))) {
       SSL_CTX_set_max_proto_version(ctx, TLS1_2_VERSION);
 #ifdef SSL_OP_NO_TLSv1_3
       SSL_CTX_set_options(ctx, SSL_OP_NO_TLSv1_3);
 #endif
    }
-#ifdef TLS1_3_VERSION
-   else if (PkeyIsEc(pkey))
-      SSL_CTX_set_min_proto_version(ctx, TLS1_3_VERSION);
-#endif
 #else
    (void)ctx;
 #endif
@@ -515,10 +499,6 @@ void LimitSessionProtoByKey(SSL *ssl)
       SSL_set_options(ssl, SSL_OP_NO_TLSv1_3);
 #endif
    }
-#ifdef TLS1_3_VERSION
-   else if (PkeyIsEc(pkey))
-      SSL_set_min_proto_version(ssl, TLS1_3_VERSION);
-#endif
 #else
    (void)ssl;
 #endif

tests/XrdClHttp/setup.sh

@@ -105,11 +105,10 @@ if ! "$OPENSSL_BIN" req -x509 -key tlscakey.pem -config tlsca.ini -out tlsca.pem
   exit 1
 fi
 
-# ECDSA P-256 host cert: TLS 1.3 uses ecdsa_secp256r1_sha256 (works on
-# this RHEL policy). RSA host certs fail TLS 1.3 tls_choose_sigalg.
-# The server requires TLS 1.3 for EC keys so curl --http1.1 cannot
-# fall back to a TLS 1.2 cipher mismatch.
-"$OPENSSL_BIN" ecparam -name prime256v1 -genkey -noout -out tls.key
+# RSA host cert: curl --http1.1 on this platform speaks TLS 1.2.
+# The server caps RSA at TLS 1.2 so tls_choose_sigalg cannot fire.
+# httph2 keeps host-ec.pem for TLS 1.3 / HTTP/2.
+"$OPENSSL_BIN" genrsa -out tls.key 2048
 chmod 0400 tls.key
 if ! "$OPENSSL_BIN" req -new -key tls.key -config tlsca.ini -out tls.csr -outform PEM -subj /CN=localhost 0<&-; then
   echo "Failed to generate host certificate request"
@@ -427,7 +426,7 @@ echo "Origin started at port $ORIGIN_PORT"
 # Confirm origin is accepting HTTPS before starting the cache. If this
 # fails the cache Stat of https://127.0.0.1:9443 becomes connection-refused
 # and checksum tests hang dumping a growing log.
-if ! curl --http1.1 --tlsv1.3 --max-time 5 --cacert "$CA_DIR/tlsca.pem" \
+if ! curl --http1.1 --tls-max 1.2 --max-time 5 --cacert "$CA_DIR/tlsca.pem" \
     "https://localhost:${ORIGIN_PORT}/.well-known/openid-configuration" \
     -o /dev/null; then
   echo "Origin is not serving HTTPS on port ${ORIGIN_PORT}"