Expose AEAD_Mode::tag_size

4 files changed, 11 insertions, 6 deletions

diff --git a/src/modes/aead/aead.h b/src/modes/aead/aead.h
index 25958a36a..d03cb295d 100644
--- a/src/modes/aead/aead.h
+++ b/src/modes/aead/aead.h
@@ -49,6 +49,11 @@ class BOTAN_DLL AEAD_Mode : public Cipher_Mode
       * modes, and large enough that random collisions are unlikely).
       */
       size_t default_nonce_size() const override { return 12; }
+
+      /**
+      * Return the size of the authentication tag used (in bytes)
+      */
+      virtual size_t tag_size() const = 0;
    };
 
 /**
diff --git a/src/modes/aead/eax/eax.h b/src/modes/aead/eax/eax.h
index 6815e3ce0..a4673a34f 100644
--- a/src/modes/aead/eax/eax.h
+++ b/src/modes/aead/eax/eax.h
@@ -35,6 +35,8 @@ class BOTAN_DLL EAX_Mode : public AEAD_Mode
       // EAX supports arbitrary nonce lengths
       bool valid_nonce_length(size_t) const override { return true; }
 
+      size_t tag_size() const { return m_tag_size; }
+
       void clear();
    protected:
       void key_schedule(const byte key[], size_t length) override;
@@ -45,8 +47,6 @@ class BOTAN_DLL EAX_Mode : public AEAD_Mode
       */
       EAX_Mode(BlockCipher* cipher, size_t tag_size);
 
-      size_t tag_size() const { return m_tag_size; }
-
       size_t block_size() const { return m_cipher->block_size(); }
 
       size_t m_tag_size;
diff --git a/src/modes/aead/gcm/gcm.h b/src/modes/aead/gcm/gcm.h
index e1479c27f..e0789f960 100644
--- a/src/modes/aead/gcm/gcm.h
+++ b/src/modes/aead/gcm/gcm.h
@@ -34,14 +34,14 @@ class BOTAN_DLL GCM_Mode : public AEAD_Mode
       // GCM supports arbitrary nonce lengths
       bool valid_nonce_length(size_t) const override { return true; }
 
+      size_t tag_size() const { return m_tag_size; }
+
       void clear();
    protected:
       void key_schedule(const byte key[], size_t length) override;
 
       GCM_Mode(BlockCipher* cipher, size_t tag_size);
 
-      size_t tag_size() const { return m_tag_size; }
-
       static const size_t BS = 16;
 
       const size_t m_tag_size;
diff --git a/src/modes/aead/ocb/ocb.h b/src/modes/aead/ocb/ocb.h
index ea7729348..c61983f44 100644
--- a/src/modes/aead/ocb/ocb.h
+++ b/src/modes/aead/ocb/ocb.h
@@ -42,6 +42,8 @@ class BOTAN_DLL OCB_Mode : public AEAD_Mode
 
       bool valid_nonce_length(size_t) const override;
 
+      size_t tag_size() const { return m_tag_size; }
+
       void clear();
 
       ~OCB_Mode();
@@ -56,8 +58,6 @@ class BOTAN_DLL OCB_Mode : public AEAD_Mode
 
       void key_schedule(const byte key[], size_t length) override;
 
-      size_t tag_size() const { return m_tag_size; }
-
       // fixme make these private
       std::unique_ptr<BlockCipher> m_cipher;
       std::unique_ptr<L_computer> m_L;