/* ====================================================================
 * Copyright (c) 2011-2013 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.
 * ====================================================================
 */

#include <openssl/opensslconf.h>

#include <stdio.h>
#include <string.h>

#if !defined(OPENSSL_NO_AES) && !defined(OPENSSL_NO_SHA1)

# include <openssl/evp.h>
# include <openssl/objects.h>
# include <openssl/aes.h>
# include <openssl/sha.h>
# include "evp_locl.h"
# include "constant_time_locl.h"

# ifndef EVP_CIPH_FLAG_AEAD_CIPHER
#  define EVP_CIPH_FLAG_AEAD_CIPHER       0x200000
#  define EVP_CTRL_AEAD_TLS1_AAD          0x16
#  define EVP_CTRL_AEAD_SET_MAC_KEY       0x17
# endif

# if !defined(EVP_CIPH_FLAG_DEFAULT_ASN1)
#  define EVP_CIPH_FLAG_DEFAULT_ASN1 0
# endif

# define TLS1_1_VERSION 0x0302

typedef struct {
    AES_KEY ks;
    SHA_CTX head, tail, md;
    size_t payload_length;      /* AAD length in decrypt case */
    union {
        unsigned int tls_ver;
        unsigned char tls_aad[16]; /* 13 used */
    } aux;
} EVP_AES_HMAC_SHA1;

# define NO_PAYLOAD_LENGTH       ((size_t)-1)

# if     defined(AES_ASM) &&     ( \
        defined(__x86_64)       || defined(__x86_64__)  || \
        defined(_M_AMD64)       || defined(_M_X64)      || \
        defined(__INTEL__)      )

#  if defined(__GNUC__) && __GNUC__>=2 && !defined(PEDANTIC)
#   define BSWAP(x) ({ unsigned int r=(x); asm ("bswapl %0":"=r"(r):"0"(r)); r; })
#  endif

extern unsigned int OPENSSL_ia32cap_P[2];
#  define AESNI_CAPABLE   (1<<(57-32))

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_cbc_encrypt(const unsigned char *in,
                       unsigned char *out,
                       size_t length,
                       const AES_KEY *key, unsigned char *ivec, int enc);

void aesni_cbc_sha1_enc(const void *inp, void *out, size_t blocks,
                        const AES_KEY *key, unsigned char iv[16],
                        SHA_CTX *ctx, const void *in0);

#  define data(ctx) ((EVP_AES_HMAC_SHA1 *)(ctx)->cipher_data)

static int aesni_cbc_hmac_sha1_init_key(EVP_CIPHER_CTX *ctx,
                                        const unsigned char *inkey,
                                        const unsigned char *iv, int enc)
{
    EVP_AES_HMAC_SHA1 *key = data(ctx);
    int ret;

    if (enc)
        ret = aesni_set_encrypt_key(inkey, ctx->key_len * 8, &key->ks);
    else
        ret = aesni_set_decrypt_key(inkey, ctx->key_len * 8, &key->ks);

    SHA1_Init(&key->head);      /* handy when benchmarking */
    key->tail = key->head;
    key->md = key->head;

    key->payload_length = NO_PAYLOAD_LENGTH;

    return ret < 0 ? 0 : 1;
}

#  define STITCHED_CALL

#  if !defined(STITCHED_CALL)
#   define aes_off 0
#  endif

void sha1_block_data_order(void *c, const void *p, size_t len);

static void sha1_update(SHA_CTX *c, const void *data, size_t len)
{
    const unsigned char *ptr = data;
    size_t res;

    if ((res = c->num)) {
        res = SHA_CBLOCK - res;
        if (len < res)
            res = len;
        SHA1_Update(c, ptr, res);
        ptr += res;
        len -= res;
    }

    res = len % SHA_CBLOCK;
    len -= res;

    if (len) {
        sha1_block_data_order(c, ptr, len / SHA_CBLOCK);

        ptr += len;
        c->Nh += len >> 29;
        c->Nl += len <<= 3;
        if (c->Nl < (unsigned int)len)
            c->Nh++;
    }

    if (res)
        SHA1_Update(c, ptr, res);
}

#  ifdef SHA1_Update
#   undef SHA1_Update
#  endif
#  define SHA1_Update sha1_update

static int aesni_cbc_hmac_sha1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
                                      const unsigned char *in, size_t len)
{
    EVP_AES_HMAC_SHA1 *key = data(ctx);
    unsigned int l;
    size_t plen = key->payload_length, iv = 0, /* explicit IV in TLS 1.1 and
                                                * later */
        sha_off = 0;
#  if defined(STITCHED_CALL)
    size_t aes_off = 0, blocks;

    sha_off = SHA_CBLOCK - key->md.num;
#  endif

    key->payload_length = NO_PAYLOAD_LENGTH;

    if (len % AES_BLOCK_SIZE)
        return 0;

    if (ctx->encrypt) {
        if (plen == NO_PAYLOAD_LENGTH)
            plen = len;
        else if (len !=
                 ((plen + SHA_DIGEST_LENGTH +
                   AES_BLOCK_SIZE) & -AES_BLOCK_SIZE))
            return 0;
        else if (key->aux.tls_ver >= TLS1_1_VERSION)
            iv = AES_BLOCK_SIZE;

#  if defined(STITCHED_CALL)
        if (plen > (sha_off + iv)
            && (blocks = (plen - (sha_off + iv)) / SHA_CBLOCK)) {
            SHA1_Update(&key->md, in + iv, sha_off);

            aesni_cbc_sha1_enc(in, out, blocks, &key->ks,
                               ctx->iv, &key->md, in + iv + sha_off);
            blocks *= SHA_CBLOCK;
            aes_off += blocks;
            sha_off += blocks;
            key->md.Nh += blocks >> 29;
            key->md.Nl += blocks <<= 3;
            if (key->md.Nl < (unsigned int)blocks)
                key->md.Nh++;
        } else {
            sha_off = 0;
        }
#  endif
        sha_off += iv;
        SHA1_Update(&key->md, in + sha_off, plen - sha_off);

        if (plen != len) {      /* "TLS" mode of operation */
            if (in != out)
                memcpy(out + aes_off, in + aes_off, plen - aes_off);

            /* calculate HMAC and append it to payload */
            SHA1_Final(out + plen, &key->md);
            key->md = key->tail;
            SHA1_Update(&key->md, out + plen, SHA_DIGEST_LENGTH);
            SHA1_Final(out + plen, &key->md);

            /* pad the payload|hmac */
            plen += SHA_DIGEST_LENGTH;
            for (l = len - plen - 1; plen < len; plen++)
                out[plen] = l;
            /* encrypt HMAC|padding at once */
            aesni_cbc_encrypt(out + aes_off, out + aes_off, len - aes_off,
                              &key->ks, ctx->iv, 1);
        } else {
            aesni_cbc_encrypt(in + aes_off, out + aes_off, len - aes_off,
                              &key->ks, ctx->iv, 1);
        }
    } else {
        union {
            unsigned int u[SHA_DIGEST_LENGTH / sizeof(unsigned int)];
            unsigned char c[32 + SHA_DIGEST_LENGTH];
        } mac, *pmac;

        /* arrange cache line alignment */
        pmac = (void *)(((size_t)mac.c + 31) & ((size_t)0 - 32));

        /* decrypt HMAC|padding at once */
        aesni_cbc_encrypt(in, out, len, &key->ks, ctx->iv, 0);

        if (plen) {             /* "TLS" mode of operation */
            size_t inp_len, mask, j, i;
            unsigned int res, maxpad, pad, bitlen;
            int ret = 1;
            union {
                unsigned int u[SHA_LBLOCK];
                unsigned char c[SHA_CBLOCK];
            } *data = (void *)key->md.data;

            if ((key->aux.tls_aad[plen - 4] << 8 | key->aux.tls_aad[plen - 3])
                >= TLS1_1_VERSION)
                iv = AES_BLOCK_SIZE;

            if (len < (iv + SHA_DIGEST_LENGTH + 1))
                return 0;

            /* omit explicit iv */
            out += iv;
            len -= iv;

            /* figure out payload length */
            pad = out[len - 1];
            maxpad = len - (SHA_DIGEST_LENGTH + 1);
            maxpad |= (255 - maxpad) >> (sizeof(maxpad) * 8 - 8);
            maxpad &= 255;

            ret &= constant_time_ge(maxpad, pad);

            inp_len = len - (SHA_DIGEST_LENGTH + pad + 1);
            mask = (0 - ((inp_len - len) >> (sizeof(inp_len) * 8 - 1)));
            inp_len &= mask;
            ret &= (int)mask;

            key->aux.tls_aad[plen - 2] = inp_len >> 8;
            key->aux.tls_aad[plen - 1] = inp_len;

            /* calculate HMAC */
            key->md = key->head;
            SHA1_Update(&key->md, key->aux.tls_aad, plen);

#  if 1
            len -= SHA_DIGEST_LENGTH; /* amend mac */
            if (len >= (256 + SHA_CBLOCK)) {
                j = (len - (256 + SHA_CBLOCK)) & (0 - SHA_CBLOCK);
                j += SHA_CBLOCK - key->md.num;
                SHA1_Update(&key->md, out, j);
                out += j;
                len -= j;
                inp_len -= j;
            }

            /* but pretend as if we hashed padded payload */
            bitlen = key->md.Nl + (inp_len << 3); /* at most 18 bits */
#   ifdef BSWAP
            bitlen = BSWAP(bitlen);
#   else
            mac.c[0] = 0;
            mac.c[1] = (unsigned char)(bitlen >> 16);
            mac.c[2] = (unsigned char)(bitlen >> 8);
            mac.c[3] = (unsigned char)bitlen;
            bitlen = mac.u[0];
#   endif

            pmac->u[0] = 0;
            pmac->u[1] = 0;
            pmac->u[2] = 0;
            pmac->u[3] = 0;
            pmac->u[4] = 0;

            for (res = key->md.num, j = 0; j < len; j++) {
                size_t c = out[j];
                mask = (j - inp_len) >> (sizeof(j) * 8 - 8);
                c &= mask;
                c |= 0x80 & ~mask & ~((inp_len - j) >> (sizeof(j) * 8 - 8));
                data->c[res++] = (unsigned char)c;

                if (res != SHA_CBLOCK)
                    continue;

                /* j is not incremented yet */
                mask = 0 - ((inp_len + 7 - j) >> (sizeof(j) * 8 - 1));
                data->u[SHA_LBLOCK - 1] |= bitlen & mask;
                sha1_block_data_order(&key->md, data, 1);
                mask &= 0 - ((j - inp_len - 72) >> (sizeof(j) * 8 - 1));
                pmac->u[0] |= key->md.h0 & mask;
                pmac->u[1] |= key->md.h1 & mask;
                pmac->u[2] |= key->md.h2 & mask;
                pmac->u[3] |= key->md.h3 & mask;
                pmac->u[4] |= key->md.h4 & mask;
                res = 0;
            }

            for (i = res; i < SHA_CBLOCK; i++, j++)
                data->c[i] = 0;

            if (res > SHA_CBLOCK - 8) {
                mask = 0 - ((inp_len + 8 - j) >> (sizeof(j) * 8 - 1));
                data->u[SHA_LBLOCK - 1] |= bitlen & mask;
                sha1_block_data_order(&key->md, data, 1);
                mask &= 0 - ((j - inp_len - 73) >> (sizeof(j) * 8 - 1));
                pmac->u[0] |= key->md.h0 & mask;
                pmac->u[1] |= key->md.h1 & mask;
                pmac->u[2] |= key->md.h2 & mask;
                pmac->u[3] |= key->md.h3 & mask;
                pmac->u[4] |= key->md.h4 & mask;

                memset(data, 0, SHA_CBLOCK);
                j += 64;
            }
            data->u[SHA_LBLOCK - 1] = bitlen;
            sha1_block_data_order(&key->md, data, 1);
            mask = 0 - ((j - inp_len - 73) >> (sizeof(j) * 8 - 1));
            pmac->u[0] |= key->md.h0 & mask;
            pmac->u[1] |= key->md.h1 & mask;
            pmac->u[2] |= key->md.h2 & mask;
            pmac->u[3] |= key->md.h3 & mask;
            pmac->u[4] |= key->md.h4 & mask;

#   ifdef BSWAP
            pmac->u[0] = BSWAP(pmac->u[0]);
            pmac->u[1] = BSWAP(pmac->u[1]);
            pmac->u[2] = BSWAP(pmac->u[2]);
            pmac->u[3] = BSWAP(pmac->u[3]);
            pmac->u[4] = BSWAP(pmac->u[4]);
#   else
            for (i = 0; i < 5; i++) {
                res = pmac->u[i];
                pmac->c[4 * i + 0] = (unsigned char)(res >> 24);
                pmac->c[4 * i + 1] = (unsigned char)(res >> 16);
                pmac->c[4 * i + 2] = (unsigned char)(res >> 8);
                pmac->c[4 * i + 3] = (unsigned char)res;
            }
#   endif
            len += SHA_DIGEST_LENGTH;
#  else
            SHA1_Update(&key->md, out, inp_len);
            res = key->md.num;
            SHA1_Final(pmac->c, &key->md);

            {
                unsigned int inp_blocks, pad_blocks;

                /* but pretend as if we hashed padded payload */
                inp_blocks =
                    1 + ((SHA_CBLOCK - 9 - res) >> (sizeof(res) * 8 - 1));
                res += (unsigned int)(len - inp_len);
                pad_blocks = res / SHA_CBLOCK;
                res %= SHA_CBLOCK;
                pad_blocks +=
                    1 + ((SHA_CBLOCK - 9 - res) >> (sizeof(res) * 8 - 1));
                for (; inp_blocks < pad_blocks; inp_blocks++)
                    sha1_block_data_order(&key->md, data, 1);
            }
#  endif
            key->md = key->tail;
            SHA1_Update(&key->md, pmac->c, SHA_DIGEST_LENGTH);
            SHA1_Final(pmac->c, &key->md);

            /* verify HMAC */
            out += inp_len;
            len -= inp_len;
#  if 1
            {
                unsigned char *p = out + len - 1 - maxpad - SHA_DIGEST_LENGTH;
                size_t off = out - p;
                unsigned int c, cmask;

                maxpad += SHA_DIGEST_LENGTH;
                for (res = 0, i = 0, j = 0; j < maxpad; j++) {
                    c = p[j];
                    cmask =
                        ((int)(j - off - SHA_DIGEST_LENGTH)) >> (sizeof(int) *
                                                                 8 - 1);
                    res |= (c ^ pad) & ~cmask; /* ... and padding */
                    cmask &= ((int)(off - 1 - j)) >> (sizeof(int) * 8 - 1);
                    res |= (c ^ pmac->c[i]) & cmask;
                    i += 1 & cmask;
                }
                maxpad -= SHA_DIGEST_LENGTH;

                res = 0 - ((0 - res) >> (sizeof(res) * 8 - 1));
                ret &= (int)~res;
            }
#  else
            for (res = 0, i = 0; i < SHA_DIGEST_LENGTH; i++)
                res |= out[i] ^ pmac->c[i];
            res = 0 - ((0 - res) >> (sizeof(res) * 8 - 1));
            ret &= (int)~res;

            /* verify padding */
            pad = (pad & ~res) | (maxpad & res);
            out = out + len - 1 - pad;
            for (res = 0, i = 0; i < pad; i++)
                res |= out[i] ^ pad;

            res = (0 - res) >> (sizeof(res) * 8 - 1);
            ret &= (int)~res;
#  endif
            return ret;
        } else {
            SHA1_Update(&key->md, out, len);
        }
    }

    return 1;
}

static int aesni_cbc_hmac_sha1_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg,
                                    void *ptr)
{
    EVP_AES_HMAC_SHA1 *key = data(ctx);

    switch (type) {
    case EVP_CTRL_AEAD_SET_MAC_KEY:
        {
            unsigned int i;
            unsigned char hmac_key[64];

            memset(hmac_key, 0, sizeof(hmac_key));

            if (arg > (int)sizeof(hmac_key)) {
                SHA1_Init(&key->head);
                SHA1_Update(&key->head, ptr, arg);
                SHA1_Final(hmac_key, &key->head);
            } else {
                memcpy(hmac_key, ptr, arg);
            }

            for (i = 0; i < sizeof(hmac_key); i++)
                hmac_key[i] ^= 0x36; /* ipad */
            SHA1_Init(&key->head);
            SHA1_Update(&key->head, hmac_key, sizeof(hmac_key));

            for (i = 0; i < sizeof(hmac_key); i++)
                hmac_key[i] ^= 0x36 ^ 0x5c; /* opad */
            SHA1_Init(&key->tail);
            SHA1_Update(&key->tail, hmac_key, sizeof(hmac_key));

            OPENSSL_cleanse(hmac_key, sizeof(hmac_key));

            return 1;
        }
    case EVP_CTRL_AEAD_TLS1_AAD:
        {
            unsigned char *p = ptr;
            unsigned int len;

            if (arg != EVP_AEAD_TLS1_AAD_LEN)
                return -1;
 
            len = p[arg - 2] << 8 | p[arg - 1];

            if (ctx->encrypt) {
                key->payload_length = len;
                if ((key->aux.tls_ver =
                     p[arg - 4] << 8 | p[arg - 3]) >= TLS1_1_VERSION) {
                    len -= AES_BLOCK_SIZE;
                    p[arg - 2] = len >> 8;
                    p[arg - 1] = len;
                }
                key->md = key->head;
                SHA1_Update(&key->md, p, arg);

                return (int)(((len + SHA_DIGEST_LENGTH +
                               AES_BLOCK_SIZE) & -AES_BLOCK_SIZE)
                             - len);
            } else {
                memcpy(key->aux.tls_aad, ptr, arg);
                key->payload_length = arg;

                return SHA_DIGEST_LENGTH;
            }
        }
    default:
        return -1;
    }
}

static EVP_CIPHER aesni_128_cbc_hmac_sha1_cipher = {
#  ifdef NID_aes_128_cbc_hmac_sha1
    NID_aes_128_cbc_hmac_sha1,
#  else
    NID_undef,
#  endif
    16, 16, 16,
    EVP_CIPH_CBC_MODE | EVP_CIPH_FLAG_DEFAULT_ASN1 |
        EVP_CIPH_FLAG_AEAD_CIPHER,
    aesni_cbc_hmac_sha1_init_key,
    aesni_cbc_hmac_sha1_cipher,
    NULL,
    sizeof(EVP_AES_HMAC_SHA1),
    EVP_CIPH_FLAG_DEFAULT_ASN1 ? NULL : EVP_CIPHER_set_asn1_iv,
    EVP_CIPH_FLAG_DEFAULT_ASN1 ? NULL : EVP_CIPHER_get_asn1_iv,
    aesni_cbc_hmac_sha1_ctrl,
    NULL
};

static EVP_CIPHER aesni_256_cbc_hmac_sha1_cipher = {
#  ifdef NID_aes_256_cbc_hmac_sha1
    NID_aes_256_cbc_hmac_sha1,
#  else
    NID_undef,
#  endif
    16, 32, 16,
    EVP_CIPH_CBC_MODE | EVP_CIPH_FLAG_DEFAULT_ASN1 |
        EVP_CIPH_FLAG_AEAD_CIPHER,
    aesni_cbc_hmac_sha1_init_key,
    aesni_cbc_hmac_sha1_cipher,
    NULL,
    sizeof(EVP_AES_HMAC_SHA1),
    EVP_CIPH_FLAG_DEFAULT_ASN1 ? NULL : EVP_CIPHER_set_asn1_iv,
    EVP_CIPH_FLAG_DEFAULT_ASN1 ? NULL : EVP_CIPHER_get_asn1_iv,
    aesni_cbc_hmac_sha1_ctrl,
    NULL
};

const EVP_CIPHER *EVP_aes_128_cbc_hmac_sha1(void)
{
    return (OPENSSL_ia32cap_P[1] & AESNI_CAPABLE ?
            &aesni_128_cbc_hmac_sha1_cipher : NULL);
}

const EVP_CIPHER *EVP_aes_256_cbc_hmac_sha1(void)
{
    return (OPENSSL_ia32cap_P[1] & AESNI_CAPABLE ?
            &aesni_256_cbc_hmac_sha1_cipher : NULL);
}
# else
const EVP_CIPHER *EVP_aes_128_cbc_hmac_sha1(void)
{
    return NULL;
}

const EVP_CIPHER *EVP_aes_256_cbc_hmac_sha1(void)
{
    return NULL;
}
# endif
#endif
