Interfaces for the AES-CBC-128 Confidentiality Algo
Change-Id: I62c06435dfe95bf86c2a49873d8ab25116588afb
Signed-off-by: Tom Joseph <tomjoseph@in.ibm.com>
diff --git a/crypt_algo.hpp b/crypt_algo.hpp
index deabf53..763a8ba 100644
--- a/crypt_algo.hpp
+++ b/crypt_algo.hpp
@@ -86,6 +86,122 @@
key k2;
};
+/**
+ * @class AlgoAES128
+ *
+ * @brief Implementation of the AES-CBC-128 Confidentiality algorithm
+ *
+ * AES-128 uses a 128-bit Cipher Key. The Cipher Key is the first 128-bits of
+ * key “K2”.Once the Cipher Key has been generated it is used to encrypt
+ * the payload data. The payload data is padded to make it an integral numbers
+ * of blocks in length (a block is 16 bytes for AES). The payload is then
+ * encrypted one block at a time from the lowest data offset to the highest
+ * using Cipher_Key as specified in AES.
+ */
+class AlgoAES128 final : public Interface
+{
+ public:
+ static constexpr size_t AESCBC128ConfHeader = 16;
+ static constexpr size_t AESCBC128BlockSize = 16;
+
+ /**
+ * RSP needs more keying material than can be provided by session
+ * integrity key alone. As a result all keying material for the RSP
+ * confidentiality algorithms will be generated by processing a
+ * pre-defined set of constants using HMAC per [RFC2104], keyed by SIK.
+ * These constants are constructed using a hexadecimal octet value
+ * repeated up to the HMAC block size in length starting with the
+ * constant 01h. This mechanism can be used to derive up to 255
+ * HMAC-block-length pieces of keying material from a single SIK.For the
+ * mandatory confidentiality algorithm AES-CBC-128, processing the
+ * following constant will generate the required amount of keying
+ * material.
+ */
+ static constexpr key const2 = { 0x02, 0x02, 0x02, 0x02, 0x02,
+ 0x02, 0x02, 0x02, 0x02, 0x02,
+ 0x02, 0x02, 0x02, 0x02, 0x02,
+ 0x02, 0x02, 0x02, 0x02, 0x02
+ };
+
+ /**
+ * If confidentiality bytes are present, the value of the first byte is
+ * one (01h). and all subsequent bytes shall have a monotonically
+ * increasing value (e.g., 02h, 03h, 04h, etc). The receiver, as an
+ * additional check for proper decryption, shall check the value of each
+ * byte of Confidentiality Pad. For AES algorithm, the pad bytes will
+ * range from 0 to 15 bytes. This predefined array would help in
+ * doing the additional check.
+ */
+ static constexpr std::array<uint8_t, AESCBC128BlockSize -1>
+ confPadBytes =
+ { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08,
+ 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F };
+
+ /**
+ * @brief Constructor for AlgoAES128
+ *
+ * @param[in] - Session Integrity key
+ */
+ explicit AlgoAES128(const buffer& sik) : Interface(sik, const2) {}
+
+ AlgoAES128() = delete;
+ ~AlgoAES128() = default;
+ AlgoAES128(const AlgoAES128&) = default;
+ AlgoAES128& operator=(const AlgoAES128&) = default;
+ AlgoAES128(AlgoAES128&&) = default;
+ AlgoAES128& operator=(AlgoAES128&&) = default;
+
+ /**
+ * @brief Decrypt the incoming payload
+ *
+ * @param[in] packet - Incoming IPMI packet
+ * @param[in] sessHeaderLen - Length of the IPMI Session Header
+ * @param[in] payloadLen - Length of the encrypted IPMI payload
+ *
+ * @return decrypted payload if the operation is successful
+ */
+ buffer decryptPayload(
+ const buffer& packet,
+ const size_t sessHeaderLen,
+ const size_t payloadLen) const override;
+
+ /**
+ * @brief Encrypt the outgoing payload
+ *
+ * @param[in] payload - plain payload for the outgoing IPMI packet
+ *
+ * @return encrypted payload if the operation is successful
+ *
+ */
+ buffer encryptPayload(buffer& payload) const override;
+
+ private:
+
+ /**
+ * @brief Decrypt the passed data
+ *
+ * @param[in] iv - Initialization vector
+ * @param[in] input - Pointer to input data
+ * @param[in] inputLen - Length of input data
+ *
+ * @return decrypted data if the operation is successful
+ */
+ buffer decryptData(const uint8_t* iv,
+ const uint8_t* input,
+ const int inputLen) const;
+
+ /**
+ * @brief Encrypt the passed data
+ *
+ * @param[in] input - Pointer to input data
+ * @param[in] inputLen - Length of input data
+ *
+ * @return encrypted data if the operation is successful
+ */
+ buffer encryptData(const uint8_t* input,
+ const int inputLen) const;
+};
+
}// namespace crypt
}// namespace cipher