diff options
Diffstat (limited to 'comm/third_party/botan/src/lib/ffi/ffi_rng.cpp')
| -rw-r--r-- | comm/third_party/botan/src/lib/ffi/ffi_rng.cpp | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/ffi/ffi_rng.cpp b/comm/third_party/botan/src/lib/ffi/ffi_rng.cpp new file mode 100644 index 0000000000..7bb365a248 --- /dev/null +++ b/comm/third_party/botan/src/lib/ffi/ffi_rng.cpp @@ -0,0 +1,183 @@ +/* +* (C) 2015,2017 Jack Lloyd +* (C) 2021 René Fischer +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/ffi.h> +#include <botan/internal/ffi_util.h> +#include <botan/internal/ffi_rng.h> +#include <botan/system_rng.h> +#include <botan/auto_rng.h> + +#include <functional> + +#if defined(BOTAN_HAS_PROCESSOR_RNG) + #include <botan/processor_rng.h> +#endif + +extern "C" { + +using namespace Botan_FFI; + +int botan_rng_init(botan_rng_t* rng_out, const char* rng_type) + { + return ffi_guard_thunk(__func__, [=]() -> int { + if(rng_out == nullptr) + return BOTAN_FFI_ERROR_NULL_POINTER; + + const std::string rng_type_s(rng_type ? rng_type : "system"); + + std::unique_ptr<Botan::RandomNumberGenerator> rng; + + if(rng_type_s == "system") + { + rng.reset(new Botan::System_RNG); + } + else if(rng_type_s == "user" || rng_type_s == "user-threadsafe") + { + rng.reset(new Botan::AutoSeeded_RNG); + } + else if(rng_type_s == "null") + { + rng.reset(new Botan::Null_RNG); + } +#if defined(BOTAN_HAS_PROCESSOR_RNG) + else if((rng_type_s == "rdrand" || rng_type_s == "hwrng") && Botan::Processor_RNG::available()) + { + rng.reset(new Botan::Processor_RNG); + } +#endif + + if(!rng) + { + return BOTAN_FFI_ERROR_NOT_IMPLEMENTED; + } + + *rng_out = new botan_rng_struct(rng.release()); + return BOTAN_FFI_SUCCESS; + }); + } + +int botan_rng_init_custom(botan_rng_t* rng_out, const char* rng_name, void* context, + int(* get_cb)(void* context, uint8_t* out, size_t out_len), + int(* add_entropy_cb)(void* context, const uint8_t input[], size_t length), + void(* destroy_cb)(void* context)) +{ +return ffi_guard_thunk(__func__,[=]() -> int { + if(rng_out == nullptr) + return BOTAN_FFI_ERROR_NULL_POINTER; + + if(rng_name == nullptr) + return BOTAN_FFI_ERROR_NULL_POINTER; + + if(get_cb == nullptr) + return BOTAN_FFI_ERROR_NULL_POINTER; + + class Custom_RNG : public Botan::RandomNumberGenerator + { + public: + Custom_RNG(const std::string& name, void* context, + int(* get_cb)(void* context, uint8_t* out, size_t out_len), + int(* add_entropy_cb)(void* context, const uint8_t input[], size_t length), + void(* destroy_cb)(void* context)) : + m_name(name) + { + m_context = context; + m_get_cb = get_cb; + m_add_entropy_cb = add_entropy_cb; + m_destroy_cb = destroy_cb; + } + + ~Custom_RNG() + { + if(m_destroy_cb) + { + m_destroy_cb(m_context); + } + } + + void randomize(uint8_t output[], size_t length) override + { + int rc = m_get_cb(m_context, output, length); + if(rc) + { + throw Botan::Invalid_State("Failed to get random from C callback, rc=" + std::to_string(rc)); + } + } + + bool accepts_input() const override + { + return m_add_entropy_cb != nullptr; + } + + void add_entropy(const uint8_t input[], size_t length) override + { + if(m_add_entropy_cb == nullptr) + { + return; + } + + int rc = m_add_entropy_cb(m_context, input, length); + if(rc) + { + throw Botan::Invalid_State("Failed to add entropy via C callback, rc=" + std::to_string(rc)); + } + } + + std::string name() const override + { + return m_name; + } + + void clear() override + { + } + + bool is_seeded() const override + { + return true; + } + + private: + std::string m_name; + void* m_context; + std::function<int(void* context, uint8_t* out, size_t out_len)> m_get_cb; + std::function<int(void* context, const uint8_t input[], size_t length)> m_add_entropy_cb; + std::function<void(void* context)> m_destroy_cb; + }; + + std::unique_ptr<Botan::RandomNumberGenerator> rng(new Custom_RNG(rng_name, context, get_cb, add_entropy_cb, destroy_cb)); + + *rng_out = new botan_rng_struct(rng.release()); + return BOTAN_FFI_SUCCESS; + }); +} + +int botan_rng_destroy(botan_rng_t rng) + { + return BOTAN_FFI_CHECKED_DELETE(rng); + } + +int botan_rng_get(botan_rng_t rng, uint8_t* out, size_t out_len) + { + return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.randomize(out, out_len); }); + } + +int botan_rng_reseed(botan_rng_t rng, size_t bits) + { + return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.reseed_from_rng(Botan::system_rng(), bits); }); + } + +int botan_rng_add_entropy(botan_rng_t rng, const uint8_t* input, size_t len) + { + return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.add_entropy(input, len); }); + } + +int botan_rng_reseed_from_rng(botan_rng_t rng, botan_rng_t source_rng, size_t bits) + { + return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.reseed_from_rng(safe_get(source_rng), bits); }); + } + +} |