text: /* $OpenBSD: eng_aesni.c,v 1.5 2014/06/12 15:49:29 deraadt Exp $ */
  /*
   * Support for Intel AES-NI intruction set
   *   Author: Huang Ying <ying.huang@intel.com>
   *
   * Intel AES-NI is a new set of Single Instruction Multiple Data
   * (SIMD) instructions that are going to be introduced in the next
   * generation of Intel processor, as of 2009. These instructions
   * enable fast and secure data encryption and decryption, using the
   * Advanced Encryption Standard (AES), defined by FIPS Publication
   * number 197.  The architecture introduces six instructions that
   * offer full hardware support for AES. Four of them support high
   * performance data encryption and decryption, and the other two
   * instructions support the AES key expansion procedure.
   *
   * The white paper can be downloaded from:
   *   http://softwarecommunity.intel.com/isn/downloads/intelavx/AES-Instructions-Set_WP.pdf
   *
   * This file is based on engines/e_padlock.c
   */
  
  /* ====================================================================
   * Copyright (c) 1999-2001 The OpenSSL Project.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. All advertising materials mentioning features or use of this
   *    software must display the following acknowledgment:
   *    "This product includes software developed by the OpenSSL Project
   *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
   *
   * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
   *    endorse or promote products derived from this software without
   *    prior written permission. For written permission, please contact
   *    licensing@OpenSSL.org.
   *
   * 5. Products derived from this software may not be called "OpenSSL"
   *    nor may "OpenSSL" appear in their names without prior written
   *    permission of the OpenSSL Project.
   *
   * 6. Redistributions of any form whatsoever must retain the following
   *    acknowledgment:
   *    "This product includes software developed by the OpenSSL Project
   *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
   *
   * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
   * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
   * OF THE POSSIBILITY OF SUCH DAMAGE.
   * ====================================================================
   *
   * This product includes cryptographic software written by Eric Young
   * (eay@cryptsoft.com).  This product includes software written by Tim
   * Hudson (tjh@cryptsoft.com).
   *
   */
  
  
  #include <openssl/opensslconf.h>
  
  #if !defined(OPENSSL_NO_HW) && !defined(OPENSSL_NO_HW_AES_NI) && !defined(OPENSSL_NO_AES)
  
  #include <stdio.h>
  #include <assert.h>
  #include "cryptlib.h"
  #include <openssl/dso.h>
  #include <openssl/engine.h>
  #include <openssl/evp.h>
  #include <openssl/aes.h>
  #include <openssl/err.h>
  
  /* AES-NI is available *ONLY* on some x86 CPUs.  Not only that it
     doesn't exist elsewhere, but it even can't be compiled on other
     platforms! */
  #undef COMPILE_HW_AESNI
  #if (defined(__x86_64) || defined(__x86_64__) || \
       defined(_M_AMD64) || defined(_M_X64) || \
       defined(OPENSSL_IA32_SSE2)) && !defined(OPENSSL_NO_ASM) && !defined(__i386__)
  #define COMPILE_HW_AESNI
  #endif
  static ENGINE *ENGINE_aesni (void);
  
  void ENGINE_load_aesni (void)
  {
  /* On non-x86 CPUs it just returns. */
  #ifdef COMPILE_HW_AESNI
  	ENGINE *toadd = ENGINE_aesni();
  	if (!toadd)
  		return;
  	ENGINE_add (toadd);
  	ENGINE_register_complete (toadd);
  	ENGINE_free (toadd);
  	ERR_clear_error ();
  #endif
  }
  
  #ifdef COMPILE_HW_AESNI
  int aesni_set_encrypt_key(const unsigned char *userKey, int bits,
      AES_KEY *key);
  int aesni_set_decrypt_key(const unsigned char *userKey, int bits,
      AES_KEY *key);
  
  void aesni_encrypt(const unsigned char *in, unsigned char *out,
      const AES_KEY *key);
  void aesni_decrypt(const unsigned char *in, unsigned char *out,
      const AES_KEY *key);
  
  void aesni_ecb_encrypt(const unsigned char *in, unsigned char *out,
      size_t length, const AES_KEY *key, int enc);
  void aesni_cbc_encrypt(const unsigned char *in, unsigned char *out,
      size_t length, const AES_KEY *key, unsigned char *ivec, int enc);
  
  /* Function for ENGINE detection and control */
  static int aesni_init(ENGINE *e);
  
  /* Cipher Stuff */
  static int aesni_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
      const int **nids, int nid);
  
  #define AESNI_MIN_ALIGN	16
  #define AESNI_ALIGN(x) \
  	((void *)(((unsigned long)(x)+AESNI_MIN_ALIGN-1)&~(AESNI_MIN_ALIGN-1)))
  
  /* Engine names */
  static const char   aesni_id[] = "aesni",
      aesni_name[] = "Intel AES-NI engine",
      no_aesni_name[] = "Intel AES-NI engine (no-aesni)";
  
  
  /* The input and output encrypted as though 128bit cfb mode is being
   * used.  The extra state information to record how much of the
   * 128bit block we have used is contained in *num;
   */
  static void
  aesni_cfb128_encrypt(const unsigned char *in, unsigned char *out,
      unsigned int len, const void *key, unsigned char ivec[16], int *num,
      int enc)
  {
  	unsigned int n;
  	size_t l = 0;
  
  	assert(in && out && key && ivec && num);
  
  	n = *num;
  
  	if (enc) {
  #if !defined(OPENSSL_SMALL_FOOTPRINT)
  			if (16%sizeof(size_t) == 0) do {	/* always true actually */
  			while (n && len) {
  				*(out++) = ivec[n] ^= *(in++);
  				--len;
  				n = (n + 1) % 16;
  			}
  			while (len >= 16) {
  				aesni_encrypt(ivec, ivec, key);
  				for (n = 0; n < 16; n += sizeof(size_t)) {
  					*(size_t*)(out + n) =
  					    *(size_t*)(ivec + n) ^= *(size_t*)(in + n);
  				}
  				len -= 16;
  				out += 16;
  				in += 16;
  			}
  			n = 0;
  			if (len) {
  				aesni_encrypt(ivec, ivec, key);
  				while (len--) {
  					out[n] = ivec[n] ^= in[n];
  					++n;
  				}
  			}
  			*num = n;
  			return;
  		} while (0);
  		/* the rest would be commonly eliminated by x86* compiler */
  #endif
  		while (l < len) {
  			if (n == 0) {
  				aesni_encrypt(ivec, ivec, key);
  			}
  			out[l] = ivec[n] ^= in[l];
  			++l;
  			n = (n + 1) % 16;
  		}
  		*num = n;
  	} else {
  #if !defined(OPENSSL_SMALL_FOOTPRINT)
  			if (16%sizeof(size_t) == 0) do {	/* always true actually */
  			while (n && len) {
  				unsigned char c;
  				*(out++) = ivec[n] ^ (c = *(in++));
  				ivec[n] = c;
  				--len;
  				n = (n + 1) % 16;
  			}
  			while (len >= 16) {
  				aesni_encrypt(ivec, ivec, key);
  				for (n = 0; n < 16; n += sizeof(size_t)) {
  					size_t t = *(size_t*)(in + n);
  					*(size_t*)(out + n) = *(size_t*)(ivec + n) ^ t;
  					*(size_t*)(ivec + n) = t;
  				}
  				len -= 16;
  				out += 16;
  				in += 16;
  			}
  			n = 0;
  			if (len) {
  				aesni_encrypt(ivec, ivec, key);
  				while (len--) {
  					unsigned char c;
  					out[n] = ivec[n] ^ (c = in[n]);
  					ivec[n] = c;
  					++n;
  				}
  			}
  			*num = n;
  			return;
  		} while (0);
  		/* the rest would be commonly eliminated by x86* compiler */
  #endif
  		while (l < len) {
  			unsigned char c;
  			if (n == 0) {
  				aesni_encrypt(ivec, ivec, key);
  			}
  			out[l] = ivec[n] ^ (c = in[l]);
  			ivec[n] = c;
  			++l;
  			n = (n + 1) % 16;
  		}
  		*num = n;
  	}
  }
  
  /* The input and output encrypted as though 128bit ofb mode is being
   * used.  The extra state information to record how much of the
   * 128bit block we have used is contained in *num;
   */
  static void
  aesni_ofb128_encrypt(const unsigned char *in, unsigned char *out,
      unsigned int len, const void *key, unsigned char ivec[16], int *num)
  {
  	unsigned int n;
  	size_t l = 0;
  
  	assert(in && out && key && ivec && num);
  
  	n = *num;
  
  #if !defined(OPENSSL_SMALL_FOOTPRINT)
  		if (16%sizeof(size_t) == 0) do { /* always true actually */
  		while (n && len) {
  			*(out++) = *(in++) ^ ivec[n];
  			--len;
  			n = (n + 1) % 16;
  		}
  		while (len >= 16) {
  			aesni_encrypt(ivec, ivec, key);
  			for (n = 0; n < 16; n += sizeof(size_t))
  				*(size_t*)(out + n) =
  				    *(size_t*)(in + n) ^ *(size_t*)(ivec + n);
  			len -= 16;
  			out += 16;
  			in += 16;
  		}
  		n = 0;
  		if (len) {
  			aesni_encrypt(ivec, ivec, key);
  			while (len--) {
  				out[n] = in[n] ^ ivec[n];
  				++n;
  			}
  		}
  		*num = n;
  		return;
  	} while (0);
  	/* the rest would be commonly eliminated by x86* compiler */
  #endif
  	while (l < len) {
  		if (n == 0) {
  			aesni_encrypt(ivec, ivec, key);
  		}
  		out[l] = in[l] ^ ivec[n];
  		++l;
  		n = (n + 1) % 16;
  	}
  
  	*num = n;
  }
  /* ===== Engine "management" functions ===== */
  
  typedef unsigned long long IA32CAP;
  
  /* Prepare the ENGINE structure for registration */
  static int
  aesni_bind_helper(ENGINE *e)
  {
  	int engage;
  
  	if (sizeof(OPENSSL_ia32cap_P) > 4) {
  		engage = ((IA32CAP)OPENSSL_ia32cap_P >> 57) & 1;
  	} else {
  		IA32CAP OPENSSL_ia32_cpuid(void);
  		engage = (OPENSSL_ia32_cpuid() >> 57) & 1;
  	}
  
  	/* Register everything or return with an error */
  	if (!ENGINE_set_id(e, aesni_id) ||
  	    !ENGINE_set_name(e, engage ? aesni_name : no_aesni_name) ||
  	    !ENGINE_set_init_function(e, aesni_init) ||
  	    (engage && !ENGINE_set_ciphers (e, aesni_ciphers)))
  		return 0;
  
  	/* Everything looks good */
  	return 1;
  }
  
  /* Constructor */
  static ENGINE *
  ENGINE_aesni(void)
  {
  	ENGINE *eng = ENGINE_new();
  
  	if (!eng) {
  		return NULL;
  	}
  
  	if (!aesni_bind_helper(eng)) {
  		ENGINE_free(eng);
  		return NULL;
  	}
  
  	return eng;
  }
  
  /* Check availability of the engine */
  static int
  aesni_init(ENGINE *e)
  {
  	return 1;
  }
  
  #if defined(NID_aes_128_cfb128) && ! defined (NID_aes_128_cfb)
  #define NID_aes_128_cfb	NID_aes_128_cfb128
  #endif
  
  #if defined(NID_aes_128_ofb128) && ! defined (NID_aes_128_ofb)
  #define NID_aes_128_ofb	NID_aes_128_ofb128
  #endif
  
  #if defined(NID_aes_192_cfb128) && ! defined (NID_aes_192_cfb)
  #define NID_aes_192_cfb	NID_aes_192_cfb128
  #endif
  
  #if defined(NID_aes_192_ofb128) && ! defined (NID_aes_192_ofb)
  #define NID_aes_192_ofb	NID_aes_192_ofb128
  #endif
  
  #if defined(NID_aes_256_cfb128) && ! defined (NID_aes_256_cfb)
  #define NID_aes_256_cfb	NID_aes_256_cfb128
  #endif
  
  #if defined(NID_aes_256_ofb128) && ! defined (NID_aes_256_ofb)
  #define NID_aes_256_ofb	NID_aes_256_ofb128
  #endif
  
  /* List of supported ciphers. */
  static int aesni_cipher_nids[] = {
  	NID_aes_128_ecb,
  	NID_aes_128_cbc,
  	NID_aes_128_cfb,
  	NID_aes_128_ofb,
  
  	NID_aes_192_ecb,
  	NID_aes_192_cbc,
  	NID_aes_192_cfb,
  	NID_aes_192_ofb,
  
  	NID_aes_256_ecb,
  	NID_aes_256_cbc,
  	NID_aes_256_cfb,
  	NID_aes_256_ofb,
  };
  static int aesni_cipher_nids_num =
      (sizeof(aesni_cipher_nids) / sizeof(aesni_cipher_nids[0]));
  
  typedef struct {
  	AES_KEY ks;
  	unsigned int _pad1[3];
  } AESNI_KEY;
  
  static int
  aesni_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *user_key,
      const unsigned char *iv, int enc)
  {
  	int ret;
  	AES_KEY *key = AESNI_ALIGN(ctx->cipher_data);
  
  	if ((ctx->cipher->flags & EVP_CIPH_MODE) == EVP_CIPH_CFB_MODE ||
  	    (ctx->cipher->flags & EVP_CIPH_MODE) == EVP_CIPH_OFB_MODE ||
  	    enc)
  		ret = aesni_set_encrypt_key(user_key, ctx->key_len * 8, key);
  	else
  		ret = aesni_set_decrypt_key(user_key, ctx->key_len * 8, key);
  
  	if (ret < 0) {
  		EVPerr(EVP_F_AESNI_INIT_KEY, EVP_R_AES_KEY_SETUP_FAILED);
  		return 0;
  	}
  
  	return 1;
  }
  
  static int
  aesni_cipher_ecb(EVP_CIPHER_CTX *ctx, unsigned char *out,
      const unsigned char *in, size_t inl)
  {
  	AES_KEY *key = AESNI_ALIGN(ctx->cipher_data);
  
  	aesni_ecb_encrypt(in, out, inl, key, ctx->encrypt);
  	return 1;
  }
  
  static int
  aesni_cipher_cbc(EVP_CIPHER_CTX *ctx, unsigned char *out,
      const unsigned char *in, size_t inl)
  {
  	AES_KEY *key = AESNI_ALIGN(ctx->cipher_data);
  
  	aesni_cbc_encrypt(in, out, inl, key, ctx->iv, ctx->encrypt);
  	return 1;
  }
  
  static int
  aesni_cipher_cfb(EVP_CIPHER_CTX *ctx, unsigned char *out,
      const unsigned char *in, size_t inl)
  {
  	AES_KEY *key = AESNI_ALIGN(ctx->cipher_data);
  
  	aesni_cfb128_encrypt(in, out, inl, key, ctx->iv, &ctx->num,
  	    ctx->encrypt);
  	return 1;
  }
  
  static int
  aesni_cipher_ofb(EVP_CIPHER_CTX *ctx, unsigned char *out,
      const unsigned char *in, size_t inl)
  {
  	AES_KEY *key = AESNI_ALIGN(ctx->cipher_data);
  
  	aesni_ofb128_encrypt(in, out, inl, key, ctx->iv, &ctx->num);
  	return 1;
  }
  
  #define AES_BLOCK_SIZE		16
  
  #define EVP_CIPHER_block_size_ECB	AES_BLOCK_SIZE
  #define EVP_CIPHER_block_size_CBC	AES_BLOCK_SIZE
  #define EVP_CIPHER_block_size_OFB	1
  #define EVP_CIPHER_block_size_CFB	1
  
  /* Declaring so many ciphers by hand would be a pain.
     Instead introduce a bit of preprocessor magic :-) */
  #define	DECLARE_AES_EVP(ksize,lmode,umode)	\
  static const EVP_CIPHER aesni_##ksize##_##lmode = {	\
  	NID_aes_##ksize##_##lmode,			\
  	EVP_CIPHER_block_size_##umode,			\
  	ksize / 8,					\
  	AES_BLOCK_SIZE,					\
  	0 | EVP_CIPH_##umode##_MODE,			\
  	aesni_init_key,				\
  	aesni_cipher_##lmode,				\
  	NULL,						\
  	sizeof(AESNI_KEY),				\
  	EVP_CIPHER_set_asn1_iv,				\
  	EVP_CIPHER_get_asn1_iv,				\
  	NULL,						\
  	NULL						\
  }
  
  DECLARE_AES_EVP(128, ecb, ECB);
  DECLARE_AES_EVP(128, cbc, CBC);
  DECLARE_AES_EVP(128, cfb, CFB);
  DECLARE_AES_EVP(128, ofb, OFB);
  
  DECLARE_AES_EVP(192, ecb, ECB);
  DECLARE_AES_EVP(192, cbc, CBC);
  DECLARE_AES_EVP(192, cfb, CFB);
  DECLARE_AES_EVP(192, ofb, OFB);
  
  DECLARE_AES_EVP(256, ecb, ECB);
  DECLARE_AES_EVP(256, cbc, CBC);
  DECLARE_AES_EVP(256, cfb, CFB);
  DECLARE_AES_EVP(256, ofb, OFB);
  
  static int
  aesni_ciphers(ENGINE *e, const EVP_CIPHER **cipher, const int **nids, int nid)
  {
  	/* No specific cipher => return a list of supported nids ... */
  	if (!cipher) {
  		*nids = aesni_cipher_nids;
  		return aesni_cipher_nids_num;
  	}
  
  	/* ... or the requested "cipher" otherwise */
  	switch (nid) {
  	case NID_aes_128_ecb:
  		*cipher = &aesni_128_ecb;
  		break;
  	case NID_aes_128_cbc:
  		*cipher = &aesni_128_cbc;
  		break;
  	case NID_aes_128_cfb:
  		*cipher = &aesni_128_cfb;
  		break;
  	case NID_aes_128_ofb:
  		*cipher = &aesni_128_ofb;
  		break;
  
  	case NID_aes_192_ecb:
  		*cipher = &aesni_192_ecb;
  		break;
  	case NID_aes_192_cbc:
  		*cipher = &aesni_192_cbc;
  		break;
  	case NID_aes_192_cfb:
  		*cipher = &aesni_192_cfb;
  		break;
  	case NID_aes_192_ofb:
  		*cipher = &aesni_192_ofb;
  		break;
  
  	case NID_aes_256_ecb:
  		*cipher = &aesni_256_ecb;
  		break;
  	case NID_aes_256_cbc:
  		*cipher = &aesni_256_cbc;
  		break;
  	case NID_aes_256_cfb:
  		*cipher = &aesni_256_cfb;
  		break;
  	case NID_aes_256_ofb:
  		*cipher = &aesni_256_ofb;
  		break;
  
  	default:
  		/* Sorry, we don't support this NID */
  		*cipher = NULL;
  		return 0;
  	}
  	return 1;
  }
  
  #endif /* COMPILE_HW_AESNI */
  #endif /* !defined(OPENSSL_NO_HW) && !defined(OPENSSL_NO_HW_AESNI) && !defined(OPENSSL_NO_AES) */
  