Botan 2.19.5 Crypto and TLS for C&

chacha20poly1305.h
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1/*
2* ChaCha20Poly1305 AEAD
3* (C) 2014 Jack Lloyd
4* (C) 2016 Daniel Neus, Rohde & Schwarz Cybersecurity
5*
6* Botan is released under the Simplified BSD License (see license.txt)
7*/
8
9#ifndef BOTAN_AEAD_CHACHA20_POLY1305_H_
10#define BOTAN_AEAD_CHACHA20_POLY1305_H_
11
12#include <botan/aead.h>
13#include <botan/stream_cipher.h>
14#include <botan/mac.h>
15
16 BOTAN_FUTURE_INTERNAL_HEADER(chacha20poly1305.h)
17
18namespace Botan {
19
20/**
21* Base class
22* See draft-irtf-cfrg-chacha20-poly1305-03 for specification
23* If a nonce of 64 bits is used the older version described in
24* draft-agl-tls-chacha20poly1305-04 is used instead.
25* If a nonce of 192 bits is used, XChaCha20Poly1305 is selected.
26*/
27 class BOTAN_PUBLIC_API(2,0) ChaCha20Poly1305_Mode : public AEAD_Mode
28 {
29 public:
30 void set_associated_data(const uint8_t ad[], size_t ad_len) override;
31
32 bool associated_data_requires_key() const override { return false; }
33
34 std::string name() const override { return "ChaCha20Poly1305"; }
35
36 size_t update_granularity() const override { return 64; }
37
38 Key_Length_Specification key_spec() const override
39 { return Key_Length_Specification(32); }
40
41 bool valid_nonce_length(size_t n) const override;
42
43 size_t tag_size() const override { return 16; }
44
45 void clear() override;
46
47 void reset() override;
48
49 protected:
50 std::unique_ptr<StreamCipher> m_chacha;
51 std::unique_ptr<MessageAuthenticationCode> m_poly1305;
52
53 ChaCha20Poly1305_Mode();
54
55 secure_vector<uint8_t> m_ad;
56 size_t m_nonce_len = 0;
57 size_t m_ctext_len = 0;
58
59 bool cfrg_version() const { return m_nonce_len == 12 || m_nonce_len == 24; }
60 void update_len(size_t len);
61 private:
62 void start_msg(const uint8_t nonce[], size_t nonce_len) override;
63
64 void key_schedule(const uint8_t key[], size_t length) override;
65 };
66
67/**
68* ChaCha20Poly1305 Encryption
69*/
70 class BOTAN_PUBLIC_API(2,0) ChaCha20Poly1305_Encryption final : public ChaCha20Poly1305_Mode
71 {
72 public:
73 size_t output_length(size_t input_length) const override
74 { return input_length + tag_size(); }
75
76 size_t minimum_final_size() const override { return 0; }
77
78 size_t process(uint8_t buf[], size_t size) override;
79
80 void finish(secure_vector<uint8_t>& final_block, size_t offset = 0) override;
81 };
82
83/**
84* ChaCha20Poly1305 Decryption
85*/
86 class BOTAN_PUBLIC_API(2,0) ChaCha20Poly1305_Decryption final : public ChaCha20Poly1305_Mode
87 {
88 public:
89 size_t output_length(size_t input_length) const override
90 {
91 BOTAN_ASSERT(input_length >= tag_size(), "Sufficient input");
92 return input_length - tag_size();
93 }
94
95 size_t minimum_final_size() const override { return tag_size(); }
96
97 size_t process(uint8_t buf[], size_t size) override;
98
99 void finish(secure_vector<uint8_t>& final_block, size_t offset = 0) override;
100 };
101
102}
103
104#endif
BOTAN_ASSERT
#define BOTAN_ASSERT(expr, assertion_made)
Definition: assert.h:55
Botan::AEAD_Mode
Definition: aead.h:23
Botan::AEAD_Mode::set_associated_data
virtual void set_associated_data(const uint8_t ad[], size_t ad_len)=0
Botan::ChaCha20Poly1305_Decryption
Definition: chacha20poly1305.h:87
Botan::ChaCha20Poly1305_Decryption::output_length
size_t output_length(size_t input_length) const override
Definition: chacha20poly1305.h:89
Botan::ChaCha20Poly1305_Decryption::minimum_final_size
size_t minimum_final_size() const override
Definition: chacha20poly1305.h:95
Botan::ChaCha20Poly1305_Encryption
Definition: chacha20poly1305.h:71
Botan::ChaCha20Poly1305_Encryption::minimum_final_size
size_t minimum_final_size() const override
Definition: chacha20poly1305.h:76
Botan::ChaCha20Poly1305_Encryption::output_length
size_t output_length(size_t input_length) const override
Definition: chacha20poly1305.h:73
Botan::ChaCha20Poly1305_Mode
Definition: chacha20poly1305.h:28
Botan::ChaCha20Poly1305_Mode::m_ad
secure_vector< uint8_t > m_ad
Definition: chacha20poly1305.h:55
Botan::ChaCha20Poly1305_Mode::name
std::string name() const override
Definition: chacha20poly1305.h:34
Botan::ChaCha20Poly1305_Mode::m_chacha
std::unique_ptr< StreamCipher > m_chacha
Definition: chacha20poly1305.h:50
Botan::ChaCha20Poly1305_Mode::update_granularity
size_t update_granularity() const override
Definition: chacha20poly1305.h:36
Botan::ChaCha20Poly1305_Mode::cfrg_version
bool cfrg_version() const
Definition: chacha20poly1305.h:59
Botan::ChaCha20Poly1305_Mode::tag_size
size_t tag_size() const override
Definition: chacha20poly1305.h:43
Botan::ChaCha20Poly1305_Mode::associated_data_requires_key
bool associated_data_requires_key() const override
Definition: chacha20poly1305.h:32
Botan::ChaCha20Poly1305_Mode::key_spec
Key_Length_Specification key_spec() const override
Definition: chacha20poly1305.h:38
Botan::ChaCha20Poly1305_Mode::m_poly1305
std::unique_ptr< MessageAuthenticationCode > m_poly1305
Definition: chacha20poly1305.h:51
Botan::Cipher_Mode::start_msg
virtual void start_msg(const uint8_t nonce[], size_t nonce_len)=0
Botan::Cipher_Mode::process
virtual size_t process(uint8_t msg[], size_t msg_len)=0
Botan::Cipher_Mode::reset
virtual void reset()=0
Botan::Cipher_Mode::finish
virtual void finish(secure_vector< uint8_t > &final_block, size_t offset=0)=0
Botan::Cipher_Mode::tag_size
virtual size_t tag_size() const
Definition: cipher_mode.h:174
Botan::Cipher_Mode::valid_nonce_length
virtual bool valid_nonce_length(size_t nonce_len) const =0
Botan::Key_Length_Specification
Definition: sym_algo.h:20
Botan::SymmetricAlgorithm::clear
virtual void clear()=0
final
int(* final)(unsigned char *, CTX *)
Definition: commoncrypto_hash.cpp:29
BOTAN_PUBLIC_API
#define BOTAN_PUBLIC_API(maj, min)
Definition: compiler.h:31
BOTAN_FUTURE_INTERNAL_HEADER
#define BOTAN_FUTURE_INTERNAL_HEADER(hdr)
Definition: compiler.h:136
Botan
Definition: alg_id.cpp:13
Botan::secure_vector
std::vector< T, secure_allocator< T > > secure_vector
Definition: secmem.h:65