From 294cf482ea49f690ac9eaad52f2574a90b2e51e6 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Mon, 16 May 2016 16:25:09 +0100 Subject: Convert cipher.hh to plain C --- include/olm/cipher.h | 134 +++++++++++++++++++++++++++++++++++++++++++++++++ include/olm/cipher.hh | 132 ------------------------------------------------ include/olm/ratchet.hh | 8 +-- 3 files changed, 138 insertions(+), 136 deletions(-) create mode 100644 include/olm/cipher.h delete mode 100644 include/olm/cipher.hh (limited to 'include') diff --git a/include/olm/cipher.h b/include/olm/cipher.h new file mode 100644 index 0000000..0d6fd5b --- /dev/null +++ b/include/olm/cipher.h @@ -0,0 +1,134 @@ +/* Copyright 2015 OpenMarket Ltd + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef OLM_CIPHER_H_ +#define OLM_CIPHER_H_ + +#include +#include + +#ifdef __cplusplus +extern "C" { +#endif + +struct olm_cipher; + +struct cipher_ops { + /** + * Returns the length of the message authentication code that will be + * appended to the output. + */ + size_t (*mac_length)(const struct olm_cipher *cipher); + + /** + * Returns the length of cipher-text for a given length of plain-text. + */ + size_t (*encrypt_ciphertext_length)(const struct olm_cipher *cipher, + size_t plaintext_length); + + /* + * Encrypts the plain-text into the output buffer and authenticates the + * contents of the output buffer covering both cipher-text and any other + * associated data in the output buffer. + * + * |---------------------------------------output_length-->| + * output |--ciphertext_length-->| |---mac_length-->| + * ciphertext + * + * The plain-text pointers and cipher-text pointers may be the same. + * + * Returns size_t(-1) if the length of the cipher-text or the output + * buffer is too small. Otherwise returns the length of the output buffer. + */ + size_t (*encrypt)( + const struct olm_cipher *cipher, + uint8_t const * key, size_t key_length, + uint8_t const * plaintext, size_t plaintext_length, + uint8_t * ciphertext, size_t ciphertext_length, + uint8_t * output, size_t output_length + ); + + /** + * Returns the maximum length of plain-text that a given length of + * cipher-text can contain. + */ + size_t (*decrypt_max_plaintext_length)( + const struct olm_cipher *cipher, + size_t ciphertext_length + ); + + /** + * Authenticates the input and decrypts the cipher-text into the plain-text + * buffer. + * + * |----------------------------------------input_length-->| + * input |--ciphertext_length-->| |---mac_length-->| + * ciphertext + * + * The plain-text pointers and cipher-text pointers may be the same. + * + * Returns size_t(-1) if the length of the plain-text buffer is too + * small or if the authentication check fails. Otherwise returns the length + * of the plain text. + */ + size_t (*decrypt)( + const struct olm_cipher *cipher, + uint8_t const * key, size_t key_length, + uint8_t const * input, size_t input_length, + uint8_t const * ciphertext, size_t ciphertext_length, + uint8_t * plaintext, size_t max_plaintext_length + ); + + /** destroy any private data associated with this cipher */ + void (*destruct)(struct olm_cipher *cipher); +}; + +struct olm_cipher { + const struct cipher_ops *ops; + /* cipher-specific fields follow */ +}; + +struct olm_cipher_aes_sha_256 { + struct olm_cipher base_cipher; + + uint8_t const * kdf_info; + size_t kdf_info_length; +}; + + +/** + * initialises a cipher type which uses AES256 for encryption and SHA256 for + * authentication. + * + * cipher: structure to be initialised + * + * kdf_info: context string for the HKDF used for deriving the AES256 key, HMAC + * key, and AES IV, from the key material passed to encrypt/decrypt. Note that + * this is NOT copied so must have a lifetime at least as long as the cipher + * instance. + * + * kdf_info_length: length of context string kdf_info + */ +struct olm_cipher *olm_cipher_aes_sha_256_init( + struct olm_cipher_aes_sha_256 *cipher, + uint8_t const * kdf_info, + size_t kdf_info_length); + + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* OLM_CIPHER_H_ */ diff --git a/include/olm/cipher.hh b/include/olm/cipher.hh deleted file mode 100644 index c561972..0000000 --- a/include/olm/cipher.hh +++ /dev/null @@ -1,132 +0,0 @@ -/* Copyright 2015 OpenMarket Ltd - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -#ifndef OLM_CIPHER_HH_ -#define OLM_CIPHER_HH_ - -#include -#include - -namespace olm { - -class Cipher { -public: - virtual ~Cipher(); - - /** - * Returns the length of the message authentication code that will be - * appended to the output. - */ - virtual std::size_t mac_length() const = 0; - - /** - * Returns the length of cipher-text for a given length of plain-text. - */ - virtual std::size_t encrypt_ciphertext_length( - std::size_t plaintext_length - ) const = 0; - - /* - * Encrypts the plain-text into the output buffer and authenticates the - * contents of the output buffer covering both cipher-text and any other - * associated data in the output buffer. - * - * |---------------------------------------output_length-->| - * output |--ciphertext_length-->| |---mac_length-->| - * ciphertext - * - * The plain-text pointers and cipher-text pointers may be the same. - * - * Returns std::size_t(-1) if the length of the cipher-text or the output - * buffer is too small. Otherwise returns the length of the output buffer. - */ - virtual std::size_t encrypt( - std::uint8_t const * key, std::size_t key_length, - std::uint8_t const * plaintext, std::size_t plaintext_length, - std::uint8_t * ciphertext, std::size_t ciphertext_length, - std::uint8_t * output, std::size_t output_length - ) const = 0; - - /** - * Returns the maximum length of plain-text that a given length of - * cipher-text can contain. - */ - virtual std::size_t decrypt_max_plaintext_length( - std::size_t ciphertext_length - ) const = 0; - - /** - * Authenticates the input and decrypts the cipher-text into the plain-text - * buffer. - * - * |----------------------------------------input_length-->| - * input |--ciphertext_length-->| |---mac_length-->| - * ciphertext - * - * The plain-text pointers and cipher-text pointers may be the same. - * - * Returns std::size_t(-1) if the length of the plain-text buffer is too - * small or if the authentication check fails. Otherwise returns the length - * of the plain text. - */ - virtual std::size_t decrypt( - std::uint8_t const * key, std::size_t key_length, - std::uint8_t const * input, std::size_t input_length, - std::uint8_t const * ciphertext, std::size_t ciphertext_length, - std::uint8_t * plaintext, std::size_t max_plaintext_length - ) const = 0; -}; - - -class CipherAesSha256 : public Cipher { -public: - CipherAesSha256( - std::uint8_t const * kdf_info, std::size_t kdf_info_length - ); - - virtual std::size_t mac_length() const; - - virtual std::size_t encrypt_ciphertext_length( - std::size_t plaintext_length - ) const; - - virtual std::size_t encrypt( - std::uint8_t const * key, std::size_t key_length, - std::uint8_t const * plaintext, std::size_t plaintext_length, - std::uint8_t * ciphertext, std::size_t ciphertext_length, - std::uint8_t * output, std::size_t output_length - ) const; - - virtual std::size_t decrypt_max_plaintext_length( - std::size_t ciphertext_length - ) const; - - virtual std::size_t decrypt( - std::uint8_t const * key, std::size_t key_length, - std::uint8_t const * input, std::size_t input_length, - std::uint8_t const * ciphertext, std::size_t ciphertext_length, - std::uint8_t * plaintext, std::size_t max_plaintext_length - ) const; - -private: - std::uint8_t const * kdf_info; - std::size_t kdf_info_length; -}; - - -} // namespace - - -#endif /* OLM_CIPHER_HH_ */ diff --git a/include/olm/ratchet.hh b/include/olm/ratchet.hh index b2787c7..e1d462d 100644 --- a/include/olm/ratchet.hh +++ b/include/olm/ratchet.hh @@ -17,9 +17,9 @@ #include "olm/list.hh" #include "olm/error.h" -namespace olm { +struct olm_cipher; -class Cipher; +namespace olm { typedef std::uint8_t SharedKey[olm::KEY_LENGTH]; @@ -69,14 +69,14 @@ struct Ratchet { Ratchet( KdfInfo const & kdf_info, - Cipher const & ratchet_cipher + olm_cipher const *ratchet_cipher ); /** A some strings identifying the application to feed into the KDF. */ KdfInfo const & kdf_info; /** The AEAD cipher to use for encrypting messages. */ - Cipher const & ratchet_cipher; + olm_cipher const *ratchet_cipher; /** The last error that happened encrypting or decrypting a message. */ OlmErrorCode last_error; -- cgit v1.2.3