Release memory in case of error in the OpenSSL ECDSA constructor

The current code will only fail to release the allocated memory if
called with an invalid algorithm, which won't happen, or if a
memory allocation fails in which case this might not matter much.
Still, it's cleaner to release the memory properly and might avoid
mistakes later if we look at this code while implementing a new
crypto backend.

(cherry picked from commit b141d89b27e52c3a8e76ca79ec5201d001f4fce9)

diff --git a/pdns/opensslsigners.cc b/pdns/opensslsigners.cc
index 8e3bb547bd42528ff093f218e5fd144e531f039f..abfe552bd53ba4f121c34ec90db03f1ce994466e 100644 (file)
--- a/pdns/opensslsigners.cc
+++ b/pdns/opensslsigners.cc
@@ -597,14 +597,19 @@ public:
       d_ecgroup = EC_GROUP_new_by_curve_name(NID_secp384r1);
       d_len = 48;
     } else {
+      EC_KEY_free(d_eckey);
       throw runtime_error(getName()+" unknown algorithm "+std::to_string(d_algorithm));
     }
+
     if (d_ecgroup == NULL) {
+      EC_KEY_free(d_eckey);
       throw runtime_error(getName()+" allocation of group structure failed");
     }
 
-    ret = EC_KEY_set_group(d_eckey,d_ecgroup);
+    ret = EC_KEY_set_group(d_eckey, d_ecgroup);
     if (ret != 1) {
+      EC_KEY_free(d_eckey);
+      EC_GROUP_free(d_ecgroup);
       throw runtime_error(getName()+" setting key group failed");
     }