Add functions to get size of PK ciphertext,plaintext

Needed for https://github.com/strongswan/strongswan/pull/109

2 files changed, 5 insertions, 1 deletions

diff --git a/src/lib/prov/openssl/openssl_ec.cpp b/src/lib/prov/openssl/openssl_ec.cpp
index 33f277d5a..5da466c0c 100644
--- a/src/lib/prov/openssl/openssl_ec.cpp
+++ b/src/lib/prov/openssl/openssl_ec.cpp
@@ -232,7 +232,7 @@ class OpenSSL_ECDSA_Signing_Operation final : public PK_Ops::Signature_with_EMSA
          m_order_bytes = (m_order_bits + 7) / 8;
          }
 
-      size_t signature_length() const { return 2*m_order_bytes; }
+      size_t signature_length() const override { return 2*m_order_bytes; }
 
       secure_vector<uint8_t> raw_sign(const uint8_t msg[], size_t msg_len,
                                    RandomNumberGenerator&) override
diff --git a/src/lib/prov/openssl/openssl_rsa.cpp b/src/lib/prov/openssl/openssl_rsa.cpp
index cf9c2b52b..8108526a1 100644
--- a/src/lib/prov/openssl/openssl_rsa.cpp
+++ b/src/lib/prov/openssl/openssl_rsa.cpp
@@ -57,6 +57,8 @@ class OpenSSL_RSA_Encryption_Operation final : public PK_Ops::Encryption
          m_bits = 8 * (n_size() - pad_overhead) - 1;
          }
 
+      size_t ciphertext_length(size_t) const override { return ::RSA_size(m_openssl_rsa.get()); }
+
       size_t max_input_bits() const override { return m_bits; };
 
       secure_vector<uint8_t> encrypt(const uint8_t msg[], size_t msg_len,
@@ -110,6 +112,8 @@ class OpenSSL_RSA_Decryption_Operation final : public PK_Ops::Decryption
             throw OpenSSL_Error("d2i_RSAPrivateKey");
          }
 
+      size_t plaintext_length(size_t) const override { return ::RSA_size(m_openssl_rsa.get()); }
+
       secure_vector<uint8_t> decrypt(uint8_t& valid_mask,
                                   const uint8_t msg[], size_t msg_len) override
          {