Add a compatability shim for libsodium

Not complete, just trying to hit the most commonly used APIs plus the
ones that are easy to do.

1 files changed, 109 insertions, 0 deletions

diff --git a/src/lib/compat/sodium/sodium_chacha.cpp b/src/lib/compat/sodium/sodium_chacha.cpp
new file mode 100644
index 000000000..fed7a52f6
--- /dev/null
+++ b/src/lib/compat/sodium/sodium_chacha.cpp
@@ -0,0 +1,109 @@
+/*
+* (C) 2019 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/sodium.h>
+#include <botan/stream_cipher.h>
+
+namespace Botan {
+
+int Sodium::crypto_stream_chacha20(uint8_t out[], size_t out_len,
+                                   const uint8_t nonce[], const uint8_t key[])
+   {
+   auto chacha = StreamCipher::create_or_throw("ChaCha(20)");
+   chacha->set_key(key, crypto_stream_chacha20_KEYBYTES);
+   chacha->set_iv(nonce, crypto_stream_chacha20_NONCEBYTES);
+   chacha->write_keystream(out, out_len);
+   return 0;
+   }
+
+int Sodium::crypto_stream_chacha20_xor(uint8_t out[], const uint8_t in[],
+                                       size_t in_len, const uint8_t nonce[],
+                                       const uint8_t key[])
+   {
+   return crypto_stream_chacha20_xor_ic(out, in, in_len, nonce, 0, key);
+   }
+
+int Sodium::crypto_stream_chacha20_xor_ic(uint8_t out[], const uint8_t in[],
+                                          size_t in_len,
+                                          const uint8_t nonce[], uint64_t ic,
+                                          const uint8_t key[])
+   {
+   if((ic >> 6) != 0) // otherwise multiply overflows
+      return -1;
+
+   auto chacha = StreamCipher::create_or_throw("ChaCha(20)");
+   chacha->set_key(key, crypto_stream_chacha20_KEYBYTES);
+   chacha->set_iv(nonce, crypto_stream_chacha20_NONCEBYTES);
+   chacha->seek(ic * 64);
+   chacha->cipher(in, out, in_len);
+   return 0;
+   }
+
+int Sodium::crypto_stream_chacha20_ietf(uint8_t out[], size_t out_len,
+                                        const uint8_t nonce[], const uint8_t key[])
+   {
+   auto chacha = StreamCipher::create_or_throw("ChaCha(20)");
+   chacha->set_key(key, crypto_stream_chacha20_ietf_KEYBYTES);
+   chacha->set_iv(nonce, crypto_stream_chacha20_ietf_NONCEBYTES);
+   chacha->write_keystream(out, out_len);
+   return 0;
+   }
+
+int Sodium::crypto_stream_chacha20_ietf_xor(uint8_t out[],
+                                            const uint8_t in[], size_t in_len,
+                                            const uint8_t nonce[],
+                                            const uint8_t key[])
+   {
+   return crypto_stream_chacha20_ietf_xor_ic(out, in, in_len, nonce, 0, key);
+   }
+
+int Sodium::crypto_stream_chacha20_ietf_xor_ic(uint8_t out[],
+                                               const uint8_t in[], size_t in_len,
+                                               const uint8_t nonce[], uint32_t ic,
+                                               const uint8_t key[])
+   {
+   auto chacha = StreamCipher::create_or_throw("ChaCha(20)");
+   chacha->set_key(key, crypto_stream_chacha20_ietf_KEYBYTES);
+   chacha->set_iv(nonce, crypto_stream_chacha20_ietf_NONCEBYTES);
+   chacha->seek(static_cast<uint64_t>(ic) * 64);
+   chacha->cipher(in, out, in_len);
+   return 0;
+   }
+
+int Sodium::crypto_stream_xchacha20(uint8_t out[], size_t out_len,
+                                    const uint8_t nonce[], const uint8_t key[])
+   {
+   auto chacha = StreamCipher::create_or_throw("ChaCha(20)");
+   chacha->set_key(key, crypto_stream_xchacha20_KEYBYTES);
+   chacha->set_iv(nonce, crypto_stream_xchacha20_NONCEBYTES);
+   chacha->write_keystream(out, out_len);
+   return 0;
+   }
+
+int Sodium::crypto_stream_xchacha20_xor(uint8_t out[], const uint8_t in[],
+                                       size_t in_len, const uint8_t nonce[],
+                                       const uint8_t key[])
+   {
+   return crypto_stream_xchacha20_xor_ic(out, in, in_len, nonce, 0, key);
+   }
+
+int Sodium::crypto_stream_xchacha20_xor_ic(uint8_t out[], const uint8_t in[],
+                                           size_t in_len,
+                                           const uint8_t nonce[], uint64_t ic,
+                                           const uint8_t key[])
+   {
+   if((ic >> 6) != 0) // otherwise multiply overflows
+      return -1;
+
+   auto chacha = StreamCipher::create_or_throw("ChaCha(20)");
+   chacha->set_key(key, crypto_stream_xchacha20_KEYBYTES);
+   chacha->set_iv(nonce, crypto_stream_xchacha20_NONCEBYTES);
+   chacha->seek(ic * 64);
+   chacha->cipher(in, out, in_len);
+   return 0;
+   }
+
+}