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Diffstat (limited to '')
| -rw-r--r-- | mysys_ssl/my_crypt.cc | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/mysys_ssl/my_crypt.cc b/mysys_ssl/my_crypt.cc new file mode 100644 index 00000000..00447e73 --- /dev/null +++ b/mysys_ssl/my_crypt.cc @@ -0,0 +1,369 @@ +/* + Copyright (c) 2014 Google Inc. + Copyright (c) 2014, 2019, MariaDB Corporation. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */ + +#include <my_global.h> +#include <string.h> + +#define template _template /* bug in WolfSSL 4.4.0, see also violite.h */ +#include <openssl/evp.h> +#undef template +#include <openssl/aes.h> +#include <openssl/err.h> +#include <openssl/rand.h> + +#include <my_crypt.h> +#include <ssl_compat.h> +#include <cstdint> + +#define CTX_ALIGN 16 + +class MyCTX +{ +public: + char ctx_buf[EVP_CIPHER_CTX_SIZE + CTX_ALIGN]; + EVP_CIPHER_CTX* ctx; + MyCTX() + { +#if CTX_ALIGN > 0 + uintptr_t p= ((uintptr_t)ctx_buf + (CTX_ALIGN - 1)) & ~(CTX_ALIGN - 1); + ctx = reinterpret_cast<EVP_CIPHER_CTX*>(p); +#else + ctx = (EVP_CIPHER_CTX*)ctx_buf; +#endif + + EVP_CIPHER_CTX_init(ctx); + } + virtual ~MyCTX() + { + EVP_CIPHER_CTX_reset(ctx); + ERR_remove_state(0); + } + + virtual int init(const EVP_CIPHER *cipher, int encrypt, const uchar *key, + uint klen, const uchar *iv, uint ivlen) + { + compile_time_assert(MY_AES_CTX_SIZE >= sizeof(MyCTX)); + if (unlikely(!cipher)) + return MY_AES_BAD_KEYSIZE; + + if (EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, encrypt) != 1) + return MY_AES_OPENSSL_ERROR; + + DBUG_ASSERT(EVP_CIPHER_CTX_key_length(ctx) == (int)klen); + DBUG_ASSERT(EVP_CIPHER_CTX_iv_length(ctx) <= (int)ivlen); + + return MY_AES_OK; + } + virtual int update(const uchar *src, uint slen, uchar *dst, uint *dlen) + { +#ifdef HAVE_WOLFSSL + // WolfSSL checks parameters and does not like NULL pointers to be passed to function below. + if (!src) + { + static uchar dummy[MY_AES_BLOCK_SIZE]; + DBUG_ASSERT(!slen); + src=dummy; + } +#endif + + if (EVP_CipherUpdate(ctx, dst, (int*)dlen, src, slen) != 1) + return MY_AES_OPENSSL_ERROR; + return MY_AES_OK; + } + virtual int finish(uchar *dst, uint *dlen) + { + if (EVP_CipherFinal_ex(ctx, dst, (int*)dlen) != 1) + return MY_AES_BAD_DATA; + return MY_AES_OK; + } +}; + +class MyCTX_nopad : public MyCTX +{ +public: + const uchar *key; + uint klen, source_tail_len; + uchar oiv[MY_AES_BLOCK_SIZE]; + uchar source_tail[MY_AES_BLOCK_SIZE]; + + MyCTX_nopad() : MyCTX() { } + ~MyCTX_nopad() = default; + + int init(const EVP_CIPHER *cipher, int encrypt, const uchar *key, uint klen, + const uchar *iv, uint ivlen) + { + compile_time_assert(MY_AES_CTX_SIZE >= sizeof(MyCTX_nopad)); + this->key= key; + this->klen= klen; + this->source_tail_len= 0; + if (ivlen) + memcpy(oiv, iv, ivlen); + DBUG_ASSERT(ivlen == 0 || ivlen == sizeof(oiv)); + + int res= MyCTX::init(cipher, encrypt, key, klen, iv, ivlen); + + EVP_CIPHER_CTX_set_padding(ctx, 0); + return res; + } + + /** Update last partial source block, stored in source_tail array. */ + void update_source_tail(const uchar* src, uint slen) + { + if (!slen) + return; + uint new_tail_len= (source_tail_len + slen) % MY_AES_BLOCK_SIZE; + if (new_tail_len) + { + if (slen + source_tail_len < MY_AES_BLOCK_SIZE) + { + memcpy(source_tail + source_tail_len, src, slen); + } + else + { + DBUG_ASSERT(slen > new_tail_len); + memcpy(source_tail, src + slen - new_tail_len, new_tail_len); + } + } + source_tail_len= new_tail_len; + } + + int update(const uchar *src, uint slen, uchar *dst, uint *dlen) + { + update_source_tail(src, slen); + return MyCTX::update(src, slen, dst, dlen); + } + + int finish(uchar *dst, uint *dlen) + { + if (source_tail_len) + { + /* + Not much we can do, block ciphers cannot encrypt data that aren't + a multiple of the block length. At least not without padding. + Let's do something CTR-like for the last partial block. + */ + uchar mask[MY_AES_BLOCK_SIZE]; + uint mlen; + + int rc= my_aes_crypt(MY_AES_ECB, ENCRYPTION_FLAG_ENCRYPT | ENCRYPTION_FLAG_NOPAD, + oiv, sizeof(mask), mask, &mlen, key, klen, 0, 0); + DBUG_ASSERT(rc == MY_AES_OK); + if (rc) + return rc; + DBUG_ASSERT(mlen == sizeof(mask)); + + for (uint i=0; i < source_tail_len; i++) + dst[i]= source_tail[i] ^ mask[i]; + } + *dlen= source_tail_len; + return MY_AES_OK; + } +}; + +#define make_aes_dispatcher(mode) \ + static inline const EVP_CIPHER *aes_ ## mode(uint klen) \ + { \ + switch (klen) { \ + case 16: return EVP_aes_128_ ## mode(); \ + case 24: return EVP_aes_192_ ## mode(); \ + case 32: return EVP_aes_256_ ## mode(); \ + default: return 0; \ + } \ + } + +make_aes_dispatcher(ecb) +make_aes_dispatcher(cbc) +#ifdef HAVE_EncryptAes128Ctr +make_aes_dispatcher(ctr) +#endif /* HAVE_EncryptAes128Ctr */ +#ifdef HAVE_EncryptAes128Gcm +make_aes_dispatcher(gcm) + +/* + special implementation for GCM; to fit OpenSSL AES-GCM into the + existing my_aes_* API it does the following: + - IV tail (over 12 bytes) goes to AAD + - the tag is appended to the ciphertext +*/ + +class MyCTX_gcm : public MyCTX +{ +public: + const uchar *aad; + int aadlen; + MyCTX_gcm() : MyCTX() { } + ~MyCTX_gcm() { } + + int init(const EVP_CIPHER *cipher, int encrypt, const uchar *key, uint klen, + const uchar *iv, uint ivlen) + { + compile_time_assert(MY_AES_CTX_SIZE >= sizeof(MyCTX_gcm)); + int res= MyCTX::init(cipher, encrypt, key, klen, iv, ivlen); + int real_ivlen= EVP_CIPHER_CTX_iv_length(ctx); + aad= iv + real_ivlen; + aadlen= ivlen - real_ivlen; + return res; + } + + int update(const uchar *src, uint slen, uchar *dst, uint *dlen) + { + /* + note that this GCM class cannot do streaming decryption, because + it needs the tag (which is located at the end of encrypted data) + before decrypting the data. it can encrypt data piecewise, like, first + half, then the second half, but it must decrypt all at once + */ + if (!EVP_CIPHER_CTX_encrypting(ctx)) + { + /* encrypted string must contain authenticaton tag (see MDEV-11174) */ + if (slen < MY_AES_BLOCK_SIZE) + return MY_AES_BAD_DATA; + slen-= MY_AES_BLOCK_SIZE; + if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, MY_AES_BLOCK_SIZE, + (void*)(src + slen))) + return MY_AES_OPENSSL_ERROR; + } + int unused; + if (aadlen && !EVP_CipherUpdate(ctx, NULL, &unused, aad, aadlen)) + return MY_AES_OPENSSL_ERROR; + aadlen= 0; + return MyCTX::update(src, slen, dst, dlen); + } + + int finish(uchar *dst, uint *dlen) + { + int fin; + if (!EVP_CipherFinal_ex(ctx, dst, &fin)) + return MY_AES_BAD_DATA; + DBUG_ASSERT(fin == 0); + + if (EVP_CIPHER_CTX_encrypting(ctx)) + { + if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, MY_AES_BLOCK_SIZE, dst)) + return MY_AES_OPENSSL_ERROR; + *dlen= MY_AES_BLOCK_SIZE; + } + else + *dlen= 0; + return MY_AES_OK; + } +}; + +#endif + +const EVP_CIPHER *(*ciphers[])(uint)= { + aes_ecb, aes_cbc +#ifdef HAVE_EncryptAes128Ctr + , aes_ctr +#ifdef HAVE_EncryptAes128Gcm + , aes_gcm +#endif +#endif +}; + +extern "C" { + +int my_aes_crypt_init(void *ctx, enum my_aes_mode mode, int flags, + const unsigned char* key, unsigned int klen, + const unsigned char* iv, unsigned int ivlen) +{ +#ifdef HAVE_EncryptAes128Ctr +#ifdef HAVE_EncryptAes128Gcm + if (mode == MY_AES_GCM) + if (flags & ENCRYPTION_FLAG_NOPAD) + return MY_AES_OPENSSL_ERROR; + else + new (ctx) MyCTX_gcm(); + else +#endif + if (mode == MY_AES_CTR) + new (ctx) MyCTX(); + else +#endif + if (flags & ENCRYPTION_FLAG_NOPAD) + new (ctx) MyCTX_nopad(); + else + new (ctx) MyCTX(); + return ((MyCTX*)ctx)->init(ciphers[mode](klen), flags & 1, + key, klen, iv, ivlen); +} + +int my_aes_crypt_update(void *ctx, const uchar *src, uint slen, + uchar *dst, uint *dlen) +{ + return ((MyCTX*)ctx)->update(src, slen, dst, dlen); +} + +int my_aes_crypt_finish(void *ctx, uchar *dst, uint *dlen) +{ + int res= ((MyCTX*)ctx)->finish(dst, dlen); + ((MyCTX*)ctx)->~MyCTX(); + return res; +} + +int my_aes_crypt(enum my_aes_mode mode, int flags, + const uchar *src, uint slen, uchar *dst, uint *dlen, + const uchar *key, uint klen, const uchar *iv, uint ivlen) +{ + void *ctx= alloca(MY_AES_CTX_SIZE); + int res1, res2; + uint d1= 0, d2; + if ((res1= my_aes_crypt_init(ctx, mode, flags, key, klen, iv, ivlen))) + return res1; + res1= my_aes_crypt_update(ctx, src, slen, dst, &d1); + res2= my_aes_crypt_finish(ctx, dst + d1, &d2); + if (res1 || res2) + ERR_remove_state(0); /* in case of failure clear error queue */ + else + *dlen= d1 + d2; + return res1 ? res1 : res2; +} + + +/* + calculate the length of the cyphertext from the length of the plaintext + for different AES encryption modes with padding enabled. + Without padding (ENCRYPTION_FLAG_NOPAD) cyphertext has the same length + as the plaintext +*/ +unsigned int my_aes_get_size(enum my_aes_mode mode __attribute__((unused)), unsigned int source_length) +{ +#ifdef HAVE_EncryptAes128Ctr + if (mode == MY_AES_CTR) + return source_length; +#ifdef HAVE_EncryptAes128Gcm + if (mode == MY_AES_GCM) + return source_length + MY_AES_BLOCK_SIZE; +#endif +#endif + return (source_length / MY_AES_BLOCK_SIZE + 1) * MY_AES_BLOCK_SIZE; +} + + +unsigned int my_aes_ctx_size(enum my_aes_mode) +{ + return MY_AES_CTX_SIZE; +} + +int my_random_bytes(uchar *buf, int num) +{ + if (RAND_bytes(buf, num) != 1) + return MY_AES_OPENSSL_ERROR; + return MY_AES_OK; +} + +} |