Ignore -named_curve auto value to improve backwards compatibility

Fixes #3490

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3518)

diff --git a/CHANGES b/CHANGES
index 0e8d9225db970d8c4cdcf8f3fa27629bc25942e1..97bfa554848c3a4d3a7cf781df30443a0e31f212 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -14,6 +14,10 @@
      than just the call where this user data is passed.
      [Richard Levitte]
 
+  *) Ignore the '-named_curve auto' value for compatibility of applications
+     with OpenSSL 1.0.2.
+     [Tomas Mraz <tmraz@fedoraproject.org>]
+
   *) Fragmented SSL/TLS alerts are no longer accepted. An alert message is 2
      bytes long. In theory it is permissible in SSLv3 - TLSv1.2 to fragment such
      alerts across multiple records (some of which could be empty). In practice

diff --git a/ssl/ssl_conf.c b/ssl/ssl_conf.c
index 41c7ff7d8335961e8cfb7ae23901d409971ebdcb..ab0a94ddd74a5cf0d9aac4fd33b4b346134a61e2 100644 (file)
--- a/ssl/ssl_conf.c
+++ b/ssl/ssl_conf.c
@@ -227,6 +227,14 @@ static int cmd_ECDHParameters(SSL_CONF_CTX *cctx, const char *value)
     EC_KEY *ecdh;
     int nid;
 
+    /* Ignore values supported by 1.0.2 for the automatic selection */
+    if ((cctx->flags & SSL_CONF_FLAG_FILE) &&
+        strcasecmp(value, "+automatic") == 0)
+        return 1;
+    if ((cctx->flags & SSL_CONF_FLAG_CMDLINE) &&
+        strcmp(value, "auto") == 0)
+        return 1;
+
     nid = EC_curve_nist2nid(value);
     if (nid == NID_undef)
         nid = OBJ_sn2nid(value);