Add similar decoding constructors to the private keys

2 files changed, 30 insertions, 4 deletions

diff --git a/src/pubkey/ecc_key/ecc_key.cpp b/src/pubkey/ecc_key/ecc_key.cpp
index f80e2bb15..4c91672d3 100644
--- a/src/pubkey/ecc_key/ecc_key.cpp
+++ b/src/pubkey/ecc_key/ecc_key.cpp
@@ -139,6 +139,29 @@ MemoryVector<byte> EC_PrivateKey::pkcs8_private_key() const
       .get_contents();
    }
 
+EC_PrivateKey::EC_PrivateKey(const AlgorithmIdentifier& alg_id,
+                             const MemoryRegion<byte>& key_bits)
+   {
+   domain_params = EC_Domain_Params(alg_id.parameters);
+
+   u32bit version;
+   SecureVector<byte> octstr_secret;
+
+   BER_Decoder(key_bits)
+      .start_cons(SEQUENCE)
+         .decode(version)
+         .decode(octstr_secret, OCTET_STRING)
+      .verify_end()
+      .end_cons();
+
+   if(version != 1)
+      throw Decoding_Error("Wrong key format version for EC key");
+
+   private_key = BigInt::decode(octstr_secret, octstr_secret.size());
+
+   public_key = domain().get_base_point() * private_key;
+   }
+
 /**
 * Return the PKCS #8 public key decoder
 */
diff --git a/src/pubkey/ecc_key/ecc_key.h b/src/pubkey/ecc_key/ecc_key.h
index 1b8ac3ff5..283813236 100644
--- a/src/pubkey/ecc_key/ecc_key.h
+++ b/src/pubkey/ecc_key/ecc_key.h
@@ -32,8 +32,6 @@ class BOTAN_DLL EC_PublicKey : public virtual Public_Key
    {
    public:
 
-      EC_PublicKey() : domain_encoding(EC_DOMPAR_ENC_EXPLICIT) {}
-
       EC_PublicKey(const EC_Domain_Params& dom_par,
                    const PointGFp& pub_point);
 
@@ -82,6 +80,8 @@ class BOTAN_DLL EC_PublicKey : public virtual Public_Key
       EC_Domain_Params_Encoding domain_format() const
          { return domain_encoding; }
    protected:
+      EC_PublicKey() : domain_encoding(EC_DOMPAR_ENC_EXPLICIT) {}
+
       virtual void X509_load_hook();
 
       EC_Domain_Params domain_params;
@@ -96,14 +96,15 @@ class BOTAN_DLL EC_PrivateKey : public virtual EC_PublicKey,
                                 public virtual Private_Key
    {
    public:
-      EC_PrivateKey() {}
-
       EC_PrivateKey(const EC_Domain_Params& domain,
                     const BigInt& private_key);
 
       EC_PrivateKey(RandomNumberGenerator& rng,
                     const EC_Domain_Params& domain);
 
+      EC_PrivateKey(const AlgorithmIdentifier& alg_id,
+                    const MemoryRegion<byte>& key_bits);
+
       virtual ~EC_PrivateKey() {}
 
       MemoryVector<byte> pkcs8_private_key() const;
@@ -121,6 +122,8 @@ class BOTAN_DLL EC_PrivateKey : public virtual EC_PublicKey,
       */
       const BigInt& private_value() const;
    protected:
+      EC_PrivateKey() {}
+
       virtual void PKCS8_load_hook(bool = false);
 
       BigInt private_key;