diff options
Diffstat (limited to 'src/lib/prov/openssl/openssl_mode.cpp')
| -rw-r--r-- | src/lib/prov/openssl/openssl_mode.cpp | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/src/lib/prov/openssl/openssl_mode.cpp b/src/lib/prov/openssl/openssl_mode.cpp new file mode 100644 index 000000000..77682bf5c --- /dev/null +++ b/src/lib/prov/openssl/openssl_mode.cpp @@ -0,0 +1,200 @@ +/* +* Cipher Modes via OpenSSL +* (C) 1999-2010,2015 Jack Lloyd +* (C) 2017 Alexander Bluhm (genua GmbH) +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/cipher_mode.h> +#include <botan/internal/rounding.h> +#include <botan/internal/openssl.h> +#include <openssl/evp.h> + +namespace Botan { + +namespace { + +class BOTAN_DLL OpenSSL_Cipher_Mode : public Cipher_Mode + { + public: + OpenSSL_Cipher_Mode(const std::string& name, + const EVP_CIPHER* cipher, + Cipher_Dir direction); + ~OpenSSL_Cipher_Mode(); + + std::string provider() const override { return "openssl"; } + std::string name() const override { return m_mode_name; } + + void start_msg(const uint8_t nonce[], size_t nonce_len) override; + size_t process(uint8_t msg[], size_t msg_len) override; + void finish(secure_vector<uint8_t>& final_block, size_t offset0) override; + size_t output_length(size_t input_length) const override; + size_t update_granularity() const override; + size_t minimum_final_size() const override; + size_t default_nonce_length() const override; + bool valid_nonce_length(size_t nonce_len) const override; + void clear() override; + void reset() override; + Key_Length_Specification key_spec() const override; + + private: + void key_schedule(const uint8_t key[], size_t length) override; + + const std::string m_mode_name; + const Cipher_Dir m_direction; + size_t m_block_size; + EVP_CIPHER_CTX m_cipher; + }; + +OpenSSL_Cipher_Mode::OpenSSL_Cipher_Mode(const std::string& name, + const EVP_CIPHER* algo, + Cipher_Dir direction) : + m_mode_name(name), + m_direction(direction) + { + m_block_size = EVP_CIPHER_block_size(algo); + + if(EVP_CIPHER_mode(algo) != EVP_CIPH_CBC_MODE) + throw Invalid_Argument("OpenSSL_BlockCipher: Non-CBC EVP was passed in"); + + EVP_CIPHER_CTX_init(&m_cipher); + if(!EVP_CipherInit_ex(&m_cipher, algo, nullptr, nullptr, nullptr, + m_direction == ENCRYPTION ? 1 : 0)) + throw Internal_Error("EVP_CipherInit_ex failed"); + if(!EVP_CIPHER_CTX_set_padding(&m_cipher, 0)) + throw Internal_Error("EVP_CIPHER_CTX_set_padding failed"); + } + +OpenSSL_Cipher_Mode::~OpenSSL_Cipher_Mode() + { + EVP_CIPHER_CTX_cleanup(&m_cipher); + } + +void OpenSSL_Cipher_Mode::start_msg(const uint8_t nonce[], size_t nonce_len) + { + if(!valid_nonce_length(nonce_len)) + throw Invalid_IV_Length(name(), nonce_len); + if(nonce_len) + { + if(!EVP_CipherInit_ex(&m_cipher, nullptr, nullptr, nullptr, nonce, -1)) + throw Internal_Error("EVP_CipherInit_ex nonce failed"); + } + } + +size_t OpenSSL_Cipher_Mode::process(uint8_t msg[], size_t msg_len) + { + if(msg_len == 0) + return 0; + if(msg_len > INT_MAX) + throw Internal_Error("msg_len overflow"); + int outl = msg_len; + secure_vector<uint8_t> out(outl); + + if(!EVP_CipherUpdate(&m_cipher, out.data(), &outl, msg, msg_len)) + throw Internal_Error("EVP_CipherUpdate failed"); + memcpy(msg, out.data(), outl); + return outl; + } + +void OpenSSL_Cipher_Mode::finish(secure_vector<uint8_t>& buffer, + size_t offset) + { + BOTAN_ASSERT(buffer.size() >= offset, "Offset ok"); + uint8_t* buf = buffer.data() + offset; + const size_t buf_size = buffer.size() - offset; + + size_t written = process(buf, buf_size); + int outl = buf_size - written; + secure_vector<uint8_t> out(outl); + + if(!EVP_CipherFinal_ex(&m_cipher, out.data(), &outl)) + throw Internal_Error("EVP_CipherFinal_ex failed"); + memcpy(buf + written, out.data(), outl); + written += outl; + buffer.resize(offset + written); + } + +size_t OpenSSL_Cipher_Mode::update_granularity() const + { + return m_block_size * BOTAN_BLOCK_CIPHER_PAR_MULT; + } + +size_t OpenSSL_Cipher_Mode::minimum_final_size() const + { + return 0; // no padding + } + +size_t OpenSSL_Cipher_Mode::default_nonce_length() const + { + return m_block_size; + } + +bool OpenSSL_Cipher_Mode::valid_nonce_length(size_t nonce_len) const + { + return (nonce_len == 0 || nonce_len == m_block_size); + } + +size_t OpenSSL_Cipher_Mode::output_length(size_t input_length) const + { + if(input_length == 0) + return m_block_size; + else + return round_up(input_length, m_block_size); + } + +void OpenSSL_Cipher_Mode::clear() + { + const EVP_CIPHER* algo = EVP_CIPHER_CTX_cipher(&m_cipher); + + if(!EVP_CIPHER_CTX_cleanup(&m_cipher)) + throw Internal_Error("EVP_CIPHER_CTX_cleanup failed"); + EVP_CIPHER_CTX_init(&m_cipher); + if(!EVP_CipherInit_ex(&m_cipher, algo, nullptr, nullptr, nullptr, + m_direction == ENCRYPTION ? 1 : 0)) + throw Internal_Error("EVP_CipherInit_ex clear failed"); + if(!EVP_CIPHER_CTX_set_padding(&m_cipher, 0)) + throw Internal_Error("EVP_CIPHER_CTX_set_padding clear failed"); + } + +void OpenSSL_Cipher_Mode::reset() + { + if(!EVP_CipherInit_ex(&m_cipher, nullptr, nullptr, nullptr, nullptr, -1)) + throw Internal_Error("EVP_CipherInit_ex clear failed"); + } + +Key_Length_Specification OpenSSL_Cipher_Mode::key_spec() const + { + return Key_Length_Specification(EVP_CIPHER_CTX_key_length(&m_cipher)); + } + +void OpenSSL_Cipher_Mode::key_schedule(const uint8_t key[], size_t length) + { + if(!EVP_CIPHER_CTX_set_key_length(&m_cipher, length)) + throw Invalid_Argument("EVP_CIPHER_CTX_set_key_length failed"); + if(!EVP_CipherInit_ex(&m_cipher, nullptr, nullptr, key, nullptr, -1)) + throw Internal_Error("EVP_CipherInit_ex key failed"); + } + +} + +Cipher_Mode* +make_openssl_cipher_mode(const std::string& name, Cipher_Dir direction) + { +#define MAKE_OPENSSL_MODE(evp_fn) \ + new OpenSSL_Cipher_Mode(name, (evp_fn)(), direction) + +#if defined(BOTAN_HAS_AES) && defined(BOTAN_HAS_MODE_CBC) && !defined(OPENSSL_NO_AES) + if(name == "AES-128/CBC/NoPadding") + return MAKE_OPENSSL_MODE(EVP_aes_128_cbc); + if(name == "AES-192/CBC/NoPadding") + return MAKE_OPENSSL_MODE(EVP_aes_192_cbc); + if(name == "AES-256/CBC/NoPadding") + return MAKE_OPENSSL_MODE(EVP_aes_256_cbc); +#endif + +#undef MAKE_OPENSSL_MODE + return nullptr; + } + +} |