KeyMint VTS: x25519 pubkey as SubjectPublicKeyInfo

The data for a key agreement operation should always send in the
SubjectPublicKeyInfo structure, not a raw key for X25519.

Test: VtsAidlKeyMintTargetTest
Bug: 231959070
Change-Id: Ib5157da6a986d957162fab60dbe927017cfdd703
diff --git a/security/keymint/aidl/vts/functional/KeyMintTest.cpp b/security/keymint/aidl/vts/functional/KeyMintTest.cpp
index c9e57d5..c4c7d73 100644
--- a/security/keymint/aidl/vts/functional/KeyMintTest.cpp
+++ b/security/keymint/aidl/vts/functional/KeyMintTest.cpp
@@ -7482,7 +7482,6 @@
             uint8_t privKeyData[32];
             uint8_t pubKeyData[32];
             X25519_keypair(pubKeyData, privKeyData);
-            *localPublicKey = vector<uint8_t>(pubKeyData, pubKeyData + 32);
             *localPrivKey = EVP_PKEY_Ptr(EVP_PKEY_new_raw_private_key(
                     EVP_PKEY_X25519, nullptr, privKeyData, sizeof(privKeyData)));
         } else {
@@ -7494,16 +7493,15 @@
             ASSERT_EQ(EC_KEY_generate_key(ecKey.get()), 1);
             *localPrivKey = EVP_PKEY_Ptr(EVP_PKEY_new());
             ASSERT_EQ(EVP_PKEY_set1_EC_KEY(localPrivKey->get(), ecKey.get()), 1);
-
-            // Get encoded form of the public part of the locally generated key...
-            unsigned char* p = nullptr;
-            int localPublicKeySize = i2d_PUBKEY(localPrivKey->get(), &p);
-            ASSERT_GT(localPublicKeySize, 0);
-            *localPublicKey =
-                    vector<uint8_t>(reinterpret_cast<const uint8_t*>(p),
-                                    reinterpret_cast<const uint8_t*>(p + localPublicKeySize));
-            OPENSSL_free(p);
         }
+
+        // Get encoded form of the public part of the locally generated key...
+        unsigned char* p = nullptr;
+        int localPublicKeySize = i2d_PUBKEY(localPrivKey->get(), &p);
+        ASSERT_GT(localPublicKeySize, 0);
+        *localPublicKey = vector<uint8_t>(reinterpret_cast<const uint8_t*>(p),
+                                          reinterpret_cast<const uint8_t*>(p + localPublicKeySize));
+        OPENSSL_free(p);
     }
 
     void GenerateKeyMintEcKey(EcCurve curve, EVP_PKEY_Ptr* kmPubKey) {
@@ -7598,6 +7596,9 @@
     //
     for (auto curve : ValidCurves()) {
         for (auto localCurve : ValidCurves()) {
+            SCOPED_TRACE(testing::Message()
+                         << "local-curve-" << localCurve << "-keymint-curve-" << curve);
+
             // Generate EC key locally (with access to private key material)
             EVP_PKEY_Ptr localPrivKey;
             vector<uint8_t> localPublicKey;