/* $OpenBSD: aes.c,v 1.19 2026/07/31 03:59:50 kenjiro Exp $ */
/* ====================================================================
 * Copyright (c) 2002-2006 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
 *    openssl-core@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 <string.h>

#include <openssl/aes.h>
#include <openssl/bio.h>
#include <openssl/crypto.h>
#include <openssl/modes.h>

#include "aes_local.h"
#include "crypto_arch.h"
#include "crypto_internal.h"
#include "modes_local.h"

static const unsigned char aes_wrap_default_iv[] = {
        0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6,
};

int aes_set_encrypt_key_internal(const unsigned char *userKey, const int bits,
    AES_KEY *key);
int aes_set_decrypt_key_internal(const unsigned char *userKey, const int bits,
    AES_KEY *key);
void aes_encrypt_internal(const unsigned char *in, unsigned char *out,
    const AES_KEY *key);
void aes_decrypt_internal(const unsigned char *in, unsigned char *out,
    const AES_KEY *key);

static int
aes_rounds_for_key_length(int bits)
{
        if (bits == 128)
                return 10;
        if (bits == 192)
                return 12;
        if (bits == 256)
                return 14;

        return 0;
}

int
AES_set_encrypt_key(const unsigned char *userKey, const int bits, AES_KEY *key)
{
        if (userKey == NULL || key == NULL)
                return -1;

        explicit_bzero(key->rd_key, sizeof(key->rd_key));

        if ((key->rounds = aes_rounds_for_key_length(bits)) <= 0)
                return -2;

        return aes_set_encrypt_key_internal(userKey, bits, key);
}
LCRYPTO_ALIAS(AES_set_encrypt_key);

int
AES_set_decrypt_key(const unsigned char *userKey, const int bits, AES_KEY *key)
{
        if (userKey == NULL || key == NULL)
                return -1;

        explicit_bzero(key->rd_key, sizeof(key->rd_key));

        if ((key->rounds = aes_rounds_for_key_length(bits)) <= 0)
                return -2;

        return aes_set_decrypt_key_internal(userKey, bits, key);
}
LCRYPTO_ALIAS(AES_set_decrypt_key);

void
AES_encrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
{
        aes_encrypt_internal(in, out, key);
}
LCRYPTO_ALIAS(AES_encrypt);

void
AES_decrypt(const unsigned char *in, unsigned char *out, const AES_KEY *key)
{
        aes_decrypt_internal(in, out, key);
}
LCRYPTO_ALIAS(AES_decrypt);

void
aes_encrypt_block128(const unsigned char *in, unsigned char *out, const void *key)
{
        aes_encrypt_internal(in, out, key);
}

static void
aes_decrypt_block128(const unsigned char *in, unsigned char *out, const void *key)
{
        aes_decrypt_internal(in, out, key);
}

#ifdef HAVE_AES_CBC_ENCRYPT_INTERNAL
void aes_cbc_encrypt_internal(const unsigned char *in, unsigned char *out,
    size_t len, const AES_KEY *key, unsigned char *ivec, const int enc);

#else
static inline void
aes_cbc_encrypt_internal(const unsigned char *in, unsigned char *out,
    size_t len, const AES_KEY *key, unsigned char *ivec, const int enc)
{
        if (enc)
                CRYPTO_cbc128_encrypt(in, out, len, key, ivec,
                    aes_encrypt_block128);
        else
                CRYPTO_cbc128_decrypt(in, out, len, key, ivec,
                    aes_decrypt_block128);
}
#endif

void
AES_cbc_encrypt(const unsigned char *in, unsigned char *out,
    size_t len, const AES_KEY *key, unsigned char *ivec, const int enc)
{
        aes_cbc_encrypt_internal(in, out, len, key, ivec, enc);
}
LCRYPTO_ALIAS(AES_cbc_encrypt);

/*
 * 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;
 */

void
AES_cfb128_encrypt(const unsigned char *in, unsigned char *out, size_t length,
    const AES_KEY *key, unsigned char *ivec, int *num, const int enc)
{
        CRYPTO_cfb128_encrypt(in, out, length, key, ivec, num, enc,
            aes_encrypt_block128);
}
LCRYPTO_ALIAS(AES_cfb128_encrypt);

/* N.B. This expects the input to be packed, MS bit first */
void
AES_cfb1_encrypt(const unsigned char *in, unsigned char *out, size_t length,
    const AES_KEY *key, unsigned char *ivec, int *num, const int enc)
{
        CRYPTO_cfb128_1_encrypt(in, out, length, key, ivec, num, enc,
            aes_encrypt_block128);
}
LCRYPTO_ALIAS(AES_cfb1_encrypt);

void
AES_cfb8_encrypt(const unsigned char *in, unsigned char *out, size_t length,
    const AES_KEY *key, unsigned char *ivec, int *num, const int enc)
{
        CRYPTO_cfb128_8_encrypt(in, out, length, key, ivec, num, enc,
            aes_encrypt_block128);
}
LCRYPTO_ALIAS(AES_cfb8_encrypt);

void
aes_ccm64_encrypt_generic(const unsigned char *in, unsigned char *out,
    size_t blocks, const void *key, const unsigned char ivec[16],
    unsigned char cmac[16], int encrypt)
{
        uint8_t iv[AES_BLOCK_SIZE], buf[AES_BLOCK_SIZE];
        uint8_t in_mask;
        uint64_t ctr;
        int i;

        in_mask = 0 - (encrypt != 0);

        memcpy(iv, ivec, sizeof(iv));

        ctr = crypto_load_be64toh(&iv[8]);

        while (blocks > 0) {
                crypto_store_htobe64(&iv[8], ctr);
                aes_encrypt_internal(iv, buf, key);
                ctr++;

                for (i = 0; i < 16; i++) {
                        out[i] = in[i] ^ buf[i];
                        cmac[i] ^= (in[i] & in_mask) | (out[i] & ~in_mask);
                }

                aes_encrypt_internal(cmac, cmac, key);

                in += 16;
                out += 16;
                blocks--;
        }

        explicit_bzero(buf, sizeof(buf));
        explicit_bzero(iv, sizeof(iv));
}

#ifdef HAVE_AES_CCM64_ENCRYPT_INTERNAL
void aes_ccm64_encrypt_internal(const unsigned char *in, unsigned char *out,
    size_t blocks, const void *key, const unsigned char ivec[16],
    unsigned char cmac[16], int encrypt);

#else
static inline void
aes_ccm64_encrypt_internal(const unsigned char *in, unsigned char *out,
    size_t blocks, const void *key, const unsigned char ivec[16],
    unsigned char cmac[16], int encrypt)
{
        aes_ccm64_encrypt_generic(in, out, blocks, key, ivec, cmac, encrypt);
}
#endif

void
aes_ccm64_encrypt_ccm128f(const unsigned char *in, unsigned char *out,
    size_t blocks, const void *key, const unsigned char ivec[16],
    unsigned char cmac[16])
{
        aes_ccm64_encrypt_internal(in, out, blocks, key, ivec, cmac, 1);
}

void
aes_ccm64_decrypt_ccm128f(const unsigned char *in, unsigned char *out,
    size_t blocks, const void *key, const unsigned char ivec[16],
    unsigned char cmac[16])
{
        aes_ccm64_encrypt_internal(in, out, blocks, key, ivec, cmac, 0);
}

void
aes_ctr32_encrypt_generic(const unsigned char *in, unsigned char *out,
    size_t blocks, const AES_KEY *key, const unsigned char ivec[AES_BLOCK_SIZE])
{
        uint8_t iv[AES_BLOCK_SIZE], buf[AES_BLOCK_SIZE];
        uint32_t ctr;
        int i;

        memcpy(iv, ivec, sizeof(iv));

        ctr = crypto_load_be32toh(&iv[12]);

        while (blocks > 0) {
                crypto_store_htobe32(&iv[12], ctr);
                aes_encrypt_internal(iv, buf, key);
                ctr++;

                for (i = 0; i < AES_BLOCK_SIZE; i++)
                        out[i] = in[i] ^ buf[i];

                in += 16;
                out += 16;
                blocks--;
        }

        explicit_bzero(buf, sizeof(buf));
        explicit_bzero(iv, sizeof(iv));
}

#ifdef HAVE_AES_CTR32_ENCRYPT_INTERNAL
void aes_ctr32_encrypt_internal(const unsigned char *in, unsigned char *out,
    size_t blocks, const AES_KEY *key, const unsigned char ivec[AES_BLOCK_SIZE]);

#else
static inline void
aes_ctr32_encrypt_internal(const unsigned char *in, unsigned char *out,
    size_t blocks, const AES_KEY *key, const unsigned char ivec[AES_BLOCK_SIZE])
{
        aes_ctr32_encrypt_generic(in, out, blocks, key, ivec);
}
#endif

void
aes_ctr32_encrypt_ctr128f(const unsigned char *in, unsigned char *out, size_t blocks,
    const void *key, const unsigned char ivec[AES_BLOCK_SIZE])
{
        aes_ctr32_encrypt_internal(in, out, blocks, key, ivec);
}

void
AES_ctr128_encrypt(const unsigned char *in, unsigned char *out,
    size_t length, const AES_KEY *key, unsigned char ivec[AES_BLOCK_SIZE],
    unsigned char ecount_buf[AES_BLOCK_SIZE], unsigned int *num)
{
        CRYPTO_ctr128_encrypt_ctr32(in, out, length, key, ivec, ecount_buf,
            num, aes_ctr32_encrypt_ctr128f);
}
LCRYPTO_ALIAS(AES_ctr128_encrypt);

void
AES_ecb_encrypt(const unsigned char *in, unsigned char *out,
    const AES_KEY *key, const int enc)
{
        if (AES_ENCRYPT == enc)
                AES_encrypt(in, out, key);
        else
                AES_decrypt(in, out, key);
}
LCRYPTO_ALIAS(AES_ecb_encrypt);

#ifndef HAVE_AES_ECB_ENCRYPT_INTERNAL
void
aes_ecb_encrypt_internal(const unsigned char *in, unsigned char *out,
    size_t len, const AES_KEY *key, int encrypt)
{
        while (len >= AES_BLOCK_SIZE) {
                AES_ecb_encrypt(in, out, key, encrypt);
                in += AES_BLOCK_SIZE;
                out += AES_BLOCK_SIZE;
                len -= AES_BLOCK_SIZE;
        }
}
#endif

#define N_WORDS (AES_BLOCK_SIZE / sizeof(unsigned long))
typedef struct {
        unsigned long data[N_WORDS];
} aes_block_t;

void
AES_ige_encrypt(const unsigned char *in, unsigned char *out, size_t length,
    const AES_KEY *key, unsigned char *ivec, const int enc)
{
        aes_block_t tmp, tmp2;
        aes_block_t iv;
        aes_block_t iv2;
        size_t n;
        size_t len;

        /* N.B. The IV for this mode is _twice_ the block size */

        OPENSSL_assert((length % AES_BLOCK_SIZE) == 0);

        len = length / AES_BLOCK_SIZE;

        memcpy(iv.data, ivec, AES_BLOCK_SIZE);
        memcpy(iv2.data, ivec + AES_BLOCK_SIZE, AES_BLOCK_SIZE);

        if (AES_ENCRYPT == enc) {
                while (len) {
                        memcpy(tmp.data, in, AES_BLOCK_SIZE);
                        for (n = 0; n < N_WORDS; ++n)
                                tmp2.data[n] = tmp.data[n] ^ iv.data[n];
                        AES_encrypt((unsigned char *)tmp2.data,
                            (unsigned char *)tmp2.data, key);
                        for (n = 0; n < N_WORDS; ++n)
                                tmp2.data[n] ^= iv2.data[n];
                        memcpy(out, tmp2.data, AES_BLOCK_SIZE);
                        iv = tmp2;
                        iv2 = tmp;
                        --len;
                        in += AES_BLOCK_SIZE;
                        out += AES_BLOCK_SIZE;
                }
        } else {
                while (len) {
                        memcpy(tmp.data, in, AES_BLOCK_SIZE);
                        tmp2 = tmp;
                        for (n = 0; n < N_WORDS; ++n)
                                tmp.data[n] ^= iv2.data[n];
                        AES_decrypt((unsigned char *)tmp.data,
                            (unsigned char *)tmp.data, key);
                        for (n = 0; n < N_WORDS; ++n)
                                tmp.data[n] ^= iv.data[n];
                        memcpy(out, tmp.data, AES_BLOCK_SIZE);
                        iv = tmp2;
                        iv2 = tmp;
                        --len;
                        in += AES_BLOCK_SIZE;
                        out += AES_BLOCK_SIZE;
                }
        }
        memcpy(ivec, iv.data, AES_BLOCK_SIZE);
        memcpy(ivec + AES_BLOCK_SIZE, iv2.data, AES_BLOCK_SIZE);
}
LCRYPTO_ALIAS(AES_ige_encrypt);

void
AES_ofb128_encrypt(const unsigned char *in, unsigned char *out, size_t length,
    const AES_KEY *key, unsigned char *ivec, int *num)
{
        CRYPTO_ofb128_encrypt(in, out, length, key, ivec, num,
            aes_encrypt_block128);
}
LCRYPTO_ALIAS(AES_ofb128_encrypt);

void
aes_xts_encrypt_generic(const unsigned char *in, unsigned char *out, size_t len,
    const AES_KEY *key1, const AES_KEY *key2, const unsigned char iv[16],
    int encrypt)
{
        XTS128_CONTEXT xctx;

        if (encrypt)
                xctx.block1 = aes_encrypt_block128;
        else 
                xctx.block1 = aes_decrypt_block128;

        xctx.block2 = aes_encrypt_block128;
        xctx.key1 = key1;
        xctx.key2 = key2;

        CRYPTO_xts128_encrypt(&xctx, iv, in, out, len, encrypt);
}

#ifndef HAVE_AES_XTS_ENCRYPT_INTERNAL
void
aes_xts_encrypt_internal(const unsigned char *in, unsigned char *out, size_t len,
    const AES_KEY *key1, const AES_KEY *key2, const unsigned char iv[16],
    int encrypt)
{
        aes_xts_encrypt_generic(in, out, len, key1, key2, iv, encrypt);
}
#endif

int
AES_wrap_key(AES_KEY *key, const unsigned char *iv, unsigned char *out,
    const unsigned char *in, unsigned int inlen)
{
        unsigned char *A, B[16], *R;
        unsigned int i, j, t;

        if ((inlen & 0x7) || (inlen < 16))
                return -1;
        A = B;
        t = 1;
        memmove(out + 8, in, inlen);
        if (!iv)
                iv = aes_wrap_default_iv;

        memcpy(A, iv, 8);

        for (j = 0; j < 6; j++) {
                R = out + 8;
                for (i = 0; i < inlen; i += 8, t++, R += 8) {
                        memcpy(B + 8, R, 8);
                        AES_encrypt(B, B, key);
                        A[7] ^= (unsigned char)(t & 0xff);
                        if (t > 0xff) {
                                A[6] ^= (unsigned char)((t >> 8) & 0xff);
                                A[5] ^= (unsigned char)((t >> 16) & 0xff);
                                A[4] ^= (unsigned char)((t >> 24) & 0xff);
                        }
                        memcpy(R, B + 8, 8);
                }
        }
        memcpy(out, A, 8);
        return inlen + 8;
}
LCRYPTO_ALIAS(AES_wrap_key);

int
AES_unwrap_key(AES_KEY *key, const unsigned char *iv, unsigned char *out,
    const unsigned char *in, unsigned int inlen)
{
        unsigned char *A, B[16], *R;
        unsigned int i, j, t;

        if ((inlen & 0x7) || (inlen < 24))
                return -1;
        inlen -= 8;
        A = B;
        t = 6 * (inlen >> 3);
        memcpy(A, in, 8);
        memmove(out, in + 8, inlen);
        for (j = 0; j < 6; j++) {
                R = out + inlen - 8;
                for (i = 0; i < inlen; i += 8, t--, R -= 8) {
                        A[7] ^= (unsigned char)(t & 0xff);
                        if (t > 0xff) {
                                A[6] ^= (unsigned char)((t >> 8) & 0xff);
                                A[5] ^= (unsigned char)((t >> 16) & 0xff);
                                A[4] ^= (unsigned char)((t >> 24) & 0xff);
                        }
                        memcpy(B + 8, R, 8);
                        AES_decrypt(B, B, key);
                        memcpy(R, B + 8, 8);
                }
        }
        if (!iv)
                iv = aes_wrap_default_iv;
        if (timingsafe_memcmp(A, iv, 8) != 0) {
                explicit_bzero(out, inlen);
                return 0;
        }
        return inlen;
}
LCRYPTO_ALIAS(AES_unwrap_key);