1 files changed, 36 insertions, 0 deletions
diff --git a/identity/support/src/IdentityCredentialSupport.cpp b/identity/support/src/IdentityCredentialSupport.cpp
index dc49ddc992..e9d5d6c7cc 100644
--- a/identity/support/src/IdentityCredentialSupport.cpp
+++ b/identity/support/src/IdentityCredentialSupport.cpp
@@ -1047,6 +1047,42 @@ optional<vector<uint8_t>> ecKeyPairGetPrivateKey(const vector<uint8_t>& keyPair)
     return privateKey;
 }
 
+optional<vector<uint8_t>> ecPrivateKeyToKeyPair(const vector<uint8_t>& privateKey) {
+    auto bn = BIGNUM_Ptr(BN_bin2bn(privateKey.data(), privateKey.size(), nullptr));
+    if (bn.get() == nullptr) {
+        LOG(ERROR) << "Error creating BIGNUM";
+        return {};
+    }
+
+    auto ecKey = EC_KEY_Ptr(EC_KEY_new_by_curve_name(NID_X9_62_prime256v1));
+    if (EC_KEY_set_private_key(ecKey.get(), bn.get()) != 1) {
+        LOG(ERROR) << "Error setting private key from BIGNUM";
+        return {};
+    }
+
+    auto pkey = EVP_PKEY_Ptr(EVP_PKEY_new());
+    if (pkey.get() == nullptr) {
+        LOG(ERROR) << "Memory allocation failed";
+        return {};
+    }
+
+    if (EVP_PKEY_set1_EC_KEY(pkey.get(), ecKey.get()) != 1) {
+        LOG(ERROR) << "Error getting private key";
+        return {};
+    }
+
+    int size = i2d_PrivateKey(pkey.get(), nullptr);
+    if (size == 0) {
+        LOG(ERROR) << "Error generating public key encoding";
+        return {};
+    }
+    vector<uint8_t> keyPair;
+    keyPair.resize(size);
+    unsigned char* p = keyPair.data();
+    i2d_PrivateKey(pkey.get(), &p);
+    return keyPair;
+}
+
 optional<vector<uint8_t>> ecKeyPairGetPkcs12(const vector<uint8_t>& keyPair, const string& name,
                                              const string& serialDecimal, const string& issuer,
                                              const string& subject, time_t validityNotBefore,