1 files changed, 104 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/modes/aead/chacha20poly1305/chacha20poly1305.h b/comm/third_party/botan/src/lib/modes/aead/chacha20poly1305/chacha20poly1305.h
new file mode 100644
index 0000000000..dbba58cc93
--- /dev/null
+++ b/comm/third_party/botan/src/lib/modes/aead/chacha20poly1305/chacha20poly1305.h
@@ -0,0 +1,104 @@
+/*
+* ChaCha20Poly1305 AEAD
+* (C) 2014 Jack Lloyd
+* (C) 2016 Daniel Neus, Rohde & Schwarz Cybersecurity
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_AEAD_CHACHA20_POLY1305_H_
+#define BOTAN_AEAD_CHACHA20_POLY1305_H_
+
+#include <botan/aead.h>
+#include <botan/stream_cipher.h>
+#include <botan/mac.h>
+
+BOTAN_FUTURE_INTERNAL_HEADER(chacha20poly1305.h)
+
+namespace Botan {
+
+/**
+* Base class
+* See draft-irtf-cfrg-chacha20-poly1305-03 for specification
+* If a nonce of 64 bits is used the older version described in
+* draft-agl-tls-chacha20poly1305-04 is used instead.
+* If a nonce of 192 bits is used, XChaCha20Poly1305 is selected.
+*/
+class BOTAN_PUBLIC_API(2,0) ChaCha20Poly1305_Mode : public AEAD_Mode
+   {
+   public:
+      void set_associated_data(const uint8_t ad[], size_t ad_len) override;
+
+      bool associated_data_requires_key() const override { return false; }
+
+      std::string name() const override { return "ChaCha20Poly1305"; }
+
+      size_t update_granularity() const override { return 64; }
+
+      Key_Length_Specification key_spec() const override
+         { return Key_Length_Specification(32); }
+
+      bool valid_nonce_length(size_t n) const override;
+
+      size_t tag_size() const override { return 16; }
+
+      void clear() override;
+
+      void reset() override;
+
+   protected:
+      std::unique_ptr<StreamCipher> m_chacha;
+      std::unique_ptr<MessageAuthenticationCode> m_poly1305;
+
+      ChaCha20Poly1305_Mode();
+
+      secure_vector<uint8_t> m_ad;
+      size_t m_nonce_len = 0;
+      size_t m_ctext_len = 0;
+
+      bool cfrg_version() const { return m_nonce_len == 12 || m_nonce_len == 24; }
+      void update_len(size_t len);
+   private:
+      void start_msg(const uint8_t nonce[], size_t nonce_len) override;
+
+      void key_schedule(const uint8_t key[], size_t length) override;
+   };
+
+/**
+* ChaCha20Poly1305 Encryption
+*/
+class BOTAN_PUBLIC_API(2,0) ChaCha20Poly1305_Encryption final : public ChaCha20Poly1305_Mode
+   {
+   public:
+      size_t output_length(size_t input_length) const override
+         { return input_length + tag_size(); }
+
+      size_t minimum_final_size() const override { return 0; }
+
+      size_t process(uint8_t buf[], size_t size) override;
+
+      void finish(secure_vector<uint8_t>& final_block, size_t offset = 0) override;
+   };
+
+/**
+* ChaCha20Poly1305 Decryption
+*/
+class BOTAN_PUBLIC_API(2,0) ChaCha20Poly1305_Decryption final : public ChaCha20Poly1305_Mode
+   {
+   public:
+      size_t output_length(size_t input_length) const override
+         {
+         BOTAN_ASSERT(input_length >= tag_size(), "Sufficient input");
+         return input_length - tag_size();
+         }
+
+      size_t minimum_final_size() const override { return tag_size(); }
+
+      size_t process(uint8_t buf[], size_t size) override;
+
+      void finish(secure_vector<uint8_t>& final_block, size_t offset = 0) override;
+   };
+
+}
+
+#endif