Correctly display the signing/hmac algorithm in the dgst app

In OpenSSL 1.1.1 doing an HMAC operation with (say) SHA1 would produce
output like this:

HMAC-SHA1(README.md)= 553154e4c0109ddc320bb495735906ad7135c2f1

Prior to this change master would instead display this like so:

SHA1(README.md)= 553154e4c0109ddc320bb495735906ad7135c2f1

The problem is that dgst was using EVP_PKEY_asn1_get0_info() to get
the algorithm name from the EVP_PKEY. This doesn't work with provider
based keys. Instead we introduce a new EVP_PKEY_get0_first_alg_name()
function, and an equivalent EVP_KEYMGMT_get0_first_name() function.

Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/12850)

1 files changed, 17 insertions, 0 deletions

diff --git a/crypto/evp/evp_pkey.c b/crypto/evp/evp_pkey.c
index d435c86087..f31d1d68f8 100644
--- a/crypto/evp/evp_pkey.c
+++ b/crypto/evp/evp_pkey.c
@@ -163,3 +163,20 @@ int EVP_PKEY_add1_attr_by_txt(EVP_PKEY *key,
         return 1;
     return 0;
 }
+
+const char *EVP_PKEY_get0_first_alg_name(const EVP_PKEY *key)
+{
+    const EVP_PKEY_ASN1_METHOD *ameth;
+    const char *name = NULL;
+
+    if (key->keymgmt != NULL)
+        return EVP_KEYMGMT_get0_first_name(key->keymgmt);
+
+    /* Otherwise fallback to legacy */
+    ameth = EVP_PKEY_get0_asn1(key);
+    if (ameth != NULL)
+        EVP_PKEY_asn1_get0_info(NULL, NULL,
+                                NULL, NULL, &name, ameth);
+
+    return name;
+}