diff options
Diffstat (limited to 'comm/third_party/botan/src/lib/modes/aead/aead.h')
-rw-r--r-- | comm/third_party/botan/src/lib/modes/aead/aead.h | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/modes/aead/aead.h b/comm/third_party/botan/src/lib/modes/aead/aead.h new file mode 100644 index 0000000000..442eb8ed7f --- /dev/null +++ b/comm/third_party/botan/src/lib/modes/aead/aead.h @@ -0,0 +1,147 @@ +/* +* Interface for AEAD modes +* (C) 2013 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#ifndef BOTAN_AEAD_MODE_H_ +#define BOTAN_AEAD_MODE_H_ + +#include <botan/cipher_mode.h> + +namespace Botan { + +/** +* Interface for AEAD (Authenticated Encryption with Associated Data) +* modes. These modes provide both encryption and message +* authentication, and can authenticate additional per-message data +* which is not included in the ciphertext (for instance a sequence +* number). +*/ +class BOTAN_PUBLIC_API(2,0) AEAD_Mode : public Cipher_Mode + { + public: + /** + * Create an AEAD mode + * @param algo the algorithm to create + * @param direction specify if this should be an encryption or decryption AEAD + * @param provider optional specification for provider to use + * @return an AEAD mode or a null pointer if not available + */ + static std::unique_ptr<AEAD_Mode> create(const std::string& algo, + Cipher_Dir direction, + const std::string& provider = ""); + + /** + * Create an AEAD mode, or throw + * @param algo the algorithm to create + * @param direction specify if this should be an encryption or decryption AEAD + * @param provider optional specification for provider to use + * @return an AEAD mode, or throw an exception + */ + static std::unique_ptr<AEAD_Mode> create_or_throw(const std::string& algo, + Cipher_Dir direction, + const std::string& provider = ""); + + bool authenticated() const override { return true; } + + /** + * Set associated data that is not included in the ciphertext but + * that should be authenticated. Must be called after set_key and + * before start. + * + * Unless reset by another call, the associated data is kept + * between messages. Thus, if the AD does not change, calling + * once (after set_key) is the optimum. + * + * @param ad the associated data + * @param ad_len length of add in bytes + */ + virtual void set_associated_data(const uint8_t ad[], size_t ad_len) = 0; + + /** + * Set associated data that is not included in the ciphertext but + * that should be authenticated. Must be called after set_key and + * before start. + * + * Unless reset by another call, the associated data is kept + * between messages. Thus, if the AD does not change, calling + * once (after set_key) is the optimum. + * + * Some AEADs (namely SIV) support multiple AD inputs. For + * all other modes only nominal AD input 0 is supported; all + * other values of i will cause an exception. + * + * @param ad the associated data + * @param ad_len length of add in bytes + */ + virtual void set_associated_data_n(size_t i, const uint8_t ad[], size_t ad_len); + + /** + * Returns the maximum supported number of associated data inputs which + * can be provided to set_associated_data_n + * + * If returns 0, then no associated data is supported. + */ + virtual size_t maximum_associated_data_inputs() const { return 1; } + + /** + * Most AEADs require the key to be set prior to setting the AD + * A few allow the AD to be set even before the cipher is keyed. + * Such ciphers would return false from this function. + */ + virtual bool associated_data_requires_key() const { return true; } + + /** + * Set associated data that is not included in the ciphertext but + * that should be authenticated. Must be called after set_key and + * before start. + * + * See @ref set_associated_data(). + * + * @param ad the associated data + */ + template<typename Alloc> + void set_associated_data_vec(const std::vector<uint8_t, Alloc>& ad) + { + set_associated_data(ad.data(), ad.size()); + } + + /** + * Set associated data that is not included in the ciphertext but + * that should be authenticated. Must be called after set_key and + * before start. + * + * See @ref set_associated_data(). + * + * @param ad the associated data + */ + template<typename Alloc> + void set_ad(const std::vector<uint8_t, Alloc>& ad) + { + set_associated_data(ad.data(), ad.size()); + } + + /** + * @return default AEAD nonce size (a commonly supported value among AEAD + * modes, and large enough that random collisions are unlikely) + */ + size_t default_nonce_length() const override { return 12; } + + virtual ~AEAD_Mode() = default; + }; + +/** +* Get an AEAD mode by name (eg "AES-128/GCM" or "Serpent/EAX") +* @param name AEAD name +* @param direction ENCRYPTION or DECRYPTION +*/ +inline AEAD_Mode* get_aead(const std::string& name, Cipher_Dir direction) + { + return AEAD_Mode::create(name, direction, "").release(); + } + +} + +#endif |