Handle invalid public key length in Ed25519

Closes #1850

2 files changed, 20 insertions, 14 deletions

diff --git a/src/lib/pubkey/ed25519/ed25519.h b/src/lib/pubkey/ed25519/ed25519.h
index f563115dd..51c75e641 100644
--- a/src/lib/pubkey/ed25519/ed25519.h
+++ b/src/lib/pubkey/ed25519/ed25519.h
@@ -38,18 +38,11 @@ class BOTAN_PUBLIC_API(2,2) Ed25519_PublicKey : public virtual Public_Key
       Ed25519_PublicKey(const AlgorithmIdentifier& alg_id,
                         const std::vector<uint8_t>& key_bits);
 
-      /**
-      * Create a Ed25519 Public Key.
-      * @param pub 32-byte raw public key
-      */
-      explicit Ed25519_PublicKey(const std::vector<uint8_t>& pub) : m_public(pub) {}
+      template<typename Alloc>
+      Ed25519_PublicKey(const std::vector<uint8_t, Alloc>& pub) :
+         Ed25519_PublicKey(pub.data(), pub.size()) {}
 
-      /**
-      * Create a Ed25519 Public Key.
-      * @param pub 32-byte raw public key
-      */
-      explicit Ed25519_PublicKey(const secure_vector<uint8_t>& pub) :
-         m_public(pub.begin(), pub.end()) {}
+      Ed25519_PublicKey(const uint8_t pub_key[], size_t len);
 
       std::unique_ptr<PK_Ops::Verification>
          create_verification_op(const std::string& params,
diff --git a/src/lib/pubkey/ed25519/ed25519_key.cpp b/src/lib/pubkey/ed25519/ed25519_key.cpp
index ee1d19edb..1de24aa26 100644
--- a/src/lib/pubkey/ed25519/ed25519_key.cpp
+++ b/src/lib/pubkey/ed25519/ed25519_key.cpp
@@ -28,8 +28,15 @@ bool Ed25519_PublicKey::check_key(RandomNumberGenerator&, bool) const
    // TODO could check cofactor
    }
 
+Ed25519_PublicKey::Ed25519_PublicKey(const uint8_t pub_key[], size_t pub_len)
+   {
+   if(pub_len != 32)
+      throw Decoding_Error("Invalid length for Ed25519 key");
+   m_public.assign(pub_key, pub_key + pub_len);
+   }
+
 Ed25519_PublicKey::Ed25519_PublicKey(const AlgorithmIdentifier&,
-                                           const std::vector<uint8_t>& key_bits)
+                                     const std::vector<uint8_t>& key_bits)
    {
    m_public = key_bits;
 
@@ -112,7 +119,10 @@ class Ed25519_Pure_Verify_Operation final : public PK_Ops::Verification
          {
          if(sig_len != 64)
             return false;
-         const bool ok = ed25519_verify(m_msg.data(), m_msg.size(), sig, m_key.get_public_key().data());
+
+         const std::vector<uint8_t>& pub_key = m_key.get_public_key();
+         BOTAN_ASSERT_EQUAL(pub_key.size(), 32, "Expected size");
+         const bool ok = ed25519_verify(m_msg.data(), m_msg.size(), sig, pub_key.data());
          m_msg.clear();
          return ok;
          }
@@ -144,7 +154,10 @@ class Ed25519_Hashed_Verify_Operation final : public PK_Ops::Verification
             return false;
          std::vector<uint8_t> msg_hash(m_hash->output_length());
          m_hash->final(msg_hash.data());
-         return ed25519_verify(msg_hash.data(), msg_hash.size(), sig, m_key.get_public_key().data());
+
+         const std::vector<uint8_t>& pub_key = m_key.get_public_key();
+         BOTAN_ASSERT_EQUAL(pub_key.size(), 32, "Expected size");
+         return ed25519_verify(msg_hash.data(), msg_hash.size(), sig, pub_key.data());
          }
 
    private: