From a0e9065f1f47d41c6f2bd692b5027695db79de25 Mon Sep 17 00:00:00 2001 From: Mark Haines Date: Tue, 3 Mar 2015 11:26:52 +0000 Subject: Rename the ratchet source and include files from axolotl to ratchet --- include/axolotl/axolotl.hh | 167 --------------------------------------------- include/axolotl/ratchet.hh | 167 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 167 insertions(+), 167 deletions(-) delete mode 100644 include/axolotl/axolotl.hh create mode 100644 include/axolotl/ratchet.hh (limited to 'include') diff --git a/include/axolotl/axolotl.hh b/include/axolotl/axolotl.hh deleted file mode 100644 index 9d7ff9a..0000000 --- a/include/axolotl/axolotl.hh +++ /dev/null @@ -1,167 +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. - */ - -#include "axolotl/crypto.hh" -#include "axolotl/list.hh" - -namespace axolotl { - -typedef std::uint8_t SharedKey[32]; - - -struct ChainKey { - std::uint32_t index; - SharedKey key; -}; - - -struct MessageKey { - std::uint32_t index; - Aes256Key cipher_key; - SharedKey mac_key; - Aes256Iv iv; -}; - - -struct SenderChain { - Curve25519KeyPair ratchet_key; - ChainKey chain_key; -}; - - -struct ReceiverChain { - Curve25519PublicKey ratchet_key; - ChainKey chain_key; -}; - - -struct SkippedMessageKey { - Curve25519PublicKey ratchet_key; - MessageKey message_key; -}; - - -enum struct ErrorCode { - SUCCESS = 0, /*!< There wasn't an error */ - NOT_ENOUGH_RANDOM = 1, /*!< Not enough entropy was supplied */ - OUTPUT_BUFFER_TOO_SMALL = 2, /*!< Supplied output buffer is too small */ - BAD_MESSAGE_VERSION = 3, /*!< The message version is unsupported */ - BAD_MESSAGE_FORMAT = 4, /*!< The message couldn't be decoded */ - BAD_MESSAGE_MAC = 5, /*!< The message couldn't be decrypted */ -}; - - -static std::size_t const MAX_RECEIVER_CHAINS = 5; -static std::size_t const MAX_SKIPPED_MESSAGE_KEYS = 40; - - -struct KdfInfo { - std::uint8_t const * root_info; - std::size_t root_info_length; - std::uint8_t const * ratchet_info; - std::size_t ratchet_info_length; - std::uint8_t const * message_info; - std::size_t message_info_length; -}; - - -struct Session { - - Session( - KdfInfo const & kdf_info - ); - - /** A some strings identifing the application to feed into the KDF. */ - KdfInfo kdf_info; - - /** The last error that happened encypting or decrypting a message. */ - ErrorCode last_error; - - /** The root key is used to generate chain keys from the ephemeral keys. - * A new root_key derived each time a chain key is derived. */ - SharedKey root_key; - - /** The sender chain is used to send messages. Each time a new ephemeral - * key is received from the remote server we generate a new sender chain - * with a new empheral key when we next send a message. */ - List sender_chain; - - /** The receiver chain is used to decrypt recieved messages. We store the - * last few chains so we can decrypt any out of order messages we haven't - * received yet. */ - List receiver_chains; - - /** List of message keys we've skipped over when advancing the receiver - * chain. */ - List skipped_message_keys; - - /** Initialise the session using a shared secret and the public part of the - * remote's first ratchet key */ - void initialise_as_bob( - std::uint8_t const * shared_secret, std::size_t shared_secret_length, - Curve25519PublicKey const & their_ratchet_key - ); - - /** Intialise the session using a shared secret and the public/private key - * pair for the first ratchet key */ - void initialise_as_alice( - std::uint8_t const * shared_secret, std::size_t shared_secret_length, - Curve25519KeyPair const & our_ratchet_key - ); - - /** The maximum number of bytes of output the encrypt method will write for - * a given message length. */ - std::size_t encrypt_max_output_length( - std::size_t plaintext_length - ); - - /** The number of bytes of random data the encrypt method will need to - * encrypt a message. This will be 32 bytes if the session needs to - * generate a new ephemeral key, or will be 0 bytes otherwise.*/ - std::size_t encrypt_random_length(); - - /** Encrypt some plaintext. Returns the length of the encrypted message - * or std::size_t(-1) on failure. On failure last_error will be set with - * an error code. The last_error will be NOT_ENOUGH_RANDOM if the number - * of random bytes is too small. The last_error will be - * OUTPUT_BUFFER_TOO_SMALL if the output buffer is too small. */ - std::size_t encrypt( - std::uint8_t const * plaintext, std::size_t plaintext_length, - std::uint8_t const * random, std::size_t random_length, - std::uint8_t * output, std::size_t max_output_length - ); - - /** An upper bound on the number of bytes of plaintext the decrypt method - * will write for a given input message length. */ - std::size_t decrypt_max_plaintext_length( - std::size_t input_length - ); - - /** Decrypt a message. Returns the length of the decrypted plaintext or - * std::size_t(-1) on failure. On failure last_error will be set with an - * error code. The last_error will be OUTPUT_BUFFER_TOO_SMALL if the - * plaintext buffer is too small. The last_error will be - * BAD_MESSAGE_VERSION if the message was encrypted with an unsupported - * version of the protocol. The last_error will be BAD_MESSAGE_FORMAT if - * the message headers could not be decoded. The last_error will be - * BAD_MESSAGE_MAC if the message could not be verified */ - std::size_t decrypt( - std::uint8_t const * input, std::size_t input_length, - std::uint8_t * plaintext, std::size_t max_plaintext_length - ); -}; - - -} // namespace axolotl diff --git a/include/axolotl/ratchet.hh b/include/axolotl/ratchet.hh new file mode 100644 index 0000000..9d7ff9a --- /dev/null +++ b/include/axolotl/ratchet.hh @@ -0,0 +1,167 @@ +/* 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. + */ + +#include "axolotl/crypto.hh" +#include "axolotl/list.hh" + +namespace axolotl { + +typedef std::uint8_t SharedKey[32]; + + +struct ChainKey { + std::uint32_t index; + SharedKey key; +}; + + +struct MessageKey { + std::uint32_t index; + Aes256Key cipher_key; + SharedKey mac_key; + Aes256Iv iv; +}; + + +struct SenderChain { + Curve25519KeyPair ratchet_key; + ChainKey chain_key; +}; + + +struct ReceiverChain { + Curve25519PublicKey ratchet_key; + ChainKey chain_key; +}; + + +struct SkippedMessageKey { + Curve25519PublicKey ratchet_key; + MessageKey message_key; +}; + + +enum struct ErrorCode { + SUCCESS = 0, /*!< There wasn't an error */ + NOT_ENOUGH_RANDOM = 1, /*!< Not enough entropy was supplied */ + OUTPUT_BUFFER_TOO_SMALL = 2, /*!< Supplied output buffer is too small */ + BAD_MESSAGE_VERSION = 3, /*!< The message version is unsupported */ + BAD_MESSAGE_FORMAT = 4, /*!< The message couldn't be decoded */ + BAD_MESSAGE_MAC = 5, /*!< The message couldn't be decrypted */ +}; + + +static std::size_t const MAX_RECEIVER_CHAINS = 5; +static std::size_t const MAX_SKIPPED_MESSAGE_KEYS = 40; + + +struct KdfInfo { + std::uint8_t const * root_info; + std::size_t root_info_length; + std::uint8_t const * ratchet_info; + std::size_t ratchet_info_length; + std::uint8_t const * message_info; + std::size_t message_info_length; +}; + + +struct Session { + + Session( + KdfInfo const & kdf_info + ); + + /** A some strings identifing the application to feed into the KDF. */ + KdfInfo kdf_info; + + /** The last error that happened encypting or decrypting a message. */ + ErrorCode last_error; + + /** The root key is used to generate chain keys from the ephemeral keys. + * A new root_key derived each time a chain key is derived. */ + SharedKey root_key; + + /** The sender chain is used to send messages. Each time a new ephemeral + * key is received from the remote server we generate a new sender chain + * with a new empheral key when we next send a message. */ + List sender_chain; + + /** The receiver chain is used to decrypt recieved messages. We store the + * last few chains so we can decrypt any out of order messages we haven't + * received yet. */ + List receiver_chains; + + /** List of message keys we've skipped over when advancing the receiver + * chain. */ + List skipped_message_keys; + + /** Initialise the session using a shared secret and the public part of the + * remote's first ratchet key */ + void initialise_as_bob( + std::uint8_t const * shared_secret, std::size_t shared_secret_length, + Curve25519PublicKey const & their_ratchet_key + ); + + /** Intialise the session using a shared secret and the public/private key + * pair for the first ratchet key */ + void initialise_as_alice( + std::uint8_t const * shared_secret, std::size_t shared_secret_length, + Curve25519KeyPair const & our_ratchet_key + ); + + /** The maximum number of bytes of output the encrypt method will write for + * a given message length. */ + std::size_t encrypt_max_output_length( + std::size_t plaintext_length + ); + + /** The number of bytes of random data the encrypt method will need to + * encrypt a message. This will be 32 bytes if the session needs to + * generate a new ephemeral key, or will be 0 bytes otherwise.*/ + std::size_t encrypt_random_length(); + + /** Encrypt some plaintext. Returns the length of the encrypted message + * or std::size_t(-1) on failure. On failure last_error will be set with + * an error code. The last_error will be NOT_ENOUGH_RANDOM if the number + * of random bytes is too small. The last_error will be + * OUTPUT_BUFFER_TOO_SMALL if the output buffer is too small. */ + std::size_t encrypt( + std::uint8_t const * plaintext, std::size_t plaintext_length, + std::uint8_t const * random, std::size_t random_length, + std::uint8_t * output, std::size_t max_output_length + ); + + /** An upper bound on the number of bytes of plaintext the decrypt method + * will write for a given input message length. */ + std::size_t decrypt_max_plaintext_length( + std::size_t input_length + ); + + /** Decrypt a message. Returns the length of the decrypted plaintext or + * std::size_t(-1) on failure. On failure last_error will be set with an + * error code. The last_error will be OUTPUT_BUFFER_TOO_SMALL if the + * plaintext buffer is too small. The last_error will be + * BAD_MESSAGE_VERSION if the message was encrypted with an unsupported + * version of the protocol. The last_error will be BAD_MESSAGE_FORMAT if + * the message headers could not be decoded. The last_error will be + * BAD_MESSAGE_MAC if the message could not be verified */ + std::size_t decrypt( + std::uint8_t const * input, std::size_t input_length, + std::uint8_t * plaintext, std::size_t max_plaintext_length + ); +}; + + +} // namespace axolotl -- cgit v1.2.3