/src/wolfssl-sp-math-all-8bit/wolfcrypt/src/chacha20_poly1305.c

Source
/* chacha.c
 *
 * Copyright (C) 2006-2025 wolfSSL Inc.
 *
 * This file is part of wolfSSL.
 *
 * wolfSSL 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; either version 3 of the License, or
 * (at your option) any later version.
 *
 * wolfSSL 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 Street, Fifth Floor, Boston, MA 02110-1335, USA
 */
/*

DESCRIPTION
This library contains implementation for the ChaCha20 stream cipher and
the Poly1305 authenticator, both as as combined-mode,
or Authenticated Encryption with Additional Data (AEAD) algorithm.

*/

#include <wolfssl/wolfcrypt/libwolfssl_sources.h>

#if defined(HAVE_CHACHA) && defined(HAVE_POLY1305)

#include <wolfssl/wolfcrypt/chacha20_poly1305.h>

#ifdef NO_INLINE
#include <wolfssl/wolfcrypt/misc.h>
#else
#define WOLFSSL_MISC_INCLUDED
#include <wolfcrypt/src/misc.c>
#endif

#define CHACHA20_POLY1305_AEAD_INITIAL_COUNTER  0
WOLFSSL_ABI
int wc_ChaCha20Poly1305_Encrypt(
                const byte inKey[CHACHA20_POLY1305_AEAD_KEYSIZE],
                const byte inIV[CHACHA20_POLY1305_AEAD_IV_SIZE],
                const byte* inAAD, const word32 inAADLen,
                const byte* inPlaintext, const word32 inPlaintextLen,
                byte* outCiphertext,
                byte outAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE])
{
    int ret;
    WC_DECLARE_VAR(aead, ChaChaPoly_Aead, 1, 0);

    /* Validate function arguments */
    if (!inKey || !inIV ||
        (inPlaintextLen > 0 && inPlaintext == NULL) ||
        !outCiphertext ||
        !outAuthTag)
    {
        return BAD_FUNC_ARG;
    }

    WC_ALLOC_VAR_EX(aead, ChaChaPoly_Aead, 1, NULL, DYNAMIC_TYPE_TMP_BUFFER,
        return MEMORY_E);

    ret = wc_ChaCha20Poly1305_Init(aead, inKey, inIV,
        CHACHA20_POLY1305_AEAD_ENCRYPT);
    if (ret == 0)
        ret = wc_ChaCha20Poly1305_UpdateAad(aead, inAAD, inAADLen);
    if (ret == 0)
        ret = wc_ChaCha20Poly1305_UpdateData(aead, inPlaintext, outCiphertext,
            inPlaintextLen);
    if (ret == 0)
        ret = wc_ChaCha20Poly1305_Final(aead, outAuthTag);

    WC_FREE_VAR_EX(aead, NULL, DYNAMIC_TYPE_TMP_BUFFER);

    return ret;
}

WOLFSSL_ABI
int wc_ChaCha20Poly1305_Decrypt(
                const byte inKey[CHACHA20_POLY1305_AEAD_KEYSIZE],
                const byte inIV[CHACHA20_POLY1305_AEAD_IV_SIZE],
                const byte* inAAD, const word32 inAADLen,
                const byte* inCiphertext, const word32 inCiphertextLen,
                const byte inAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE],
                byte* outPlaintext)
{
    int ret;
    WC_DECLARE_VAR(aead, ChaChaPoly_Aead, 1, 0);
    byte calculatedAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE];

    /* Validate function arguments */
    if (!inKey || !inIV ||
        (inCiphertextLen > 0 && inCiphertext == NULL) ||
        !inAuthTag ||
        !outPlaintext)
    {
        return BAD_FUNC_ARG;
    }

    WC_ALLOC_VAR_EX(aead, ChaChaPoly_Aead, 1, NULL, DYNAMIC_TYPE_TMP_BUFFER,
        return MEMORY_E);

    XMEMSET(calculatedAuthTag, 0, sizeof(calculatedAuthTag));

    ret = wc_ChaCha20Poly1305_Init(aead, inKey, inIV,
        CHACHA20_POLY1305_AEAD_DECRYPT);
    if (ret == 0)
        ret = wc_ChaCha20Poly1305_UpdateAad(aead, inAAD, inAADLen);
    if (ret == 0)
        ret = wc_ChaCha20Poly1305_UpdateData(aead, inCiphertext, outPlaintext,
            inCiphertextLen);
    if (ret == 0)
        ret = wc_ChaCha20Poly1305_Final(aead, calculatedAuthTag);
    if (ret == 0)
        ret = wc_ChaCha20Poly1305_CheckTag(inAuthTag, calculatedAuthTag);

    WC_FREE_VAR_EX(aead, NULL, DYNAMIC_TYPE_TMP_BUFFER);

    return ret;
}

int wc_ChaCha20Poly1305_CheckTag(
    const byte authTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE],
    const byte authTagChk[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE])
{
    int ret = 0;
    if (authTag == NULL || authTagChk == NULL) {
        return BAD_FUNC_ARG;
    }
    if (ConstantCompare(authTag, authTagChk,
            CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE) != 0) {
        ret = MAC_CMP_FAILED_E;
    }
    return ret;
}

int wc_ChaCha20Poly1305_Init(ChaChaPoly_Aead* aead,
    const byte inKey[CHACHA20_POLY1305_AEAD_KEYSIZE],
    const byte inIV[CHACHA20_POLY1305_AEAD_IV_SIZE],
    int isEncrypt)
{
    int ret;
    byte authKey[CHACHA20_POLY1305_AEAD_KEYSIZE];

    /* check arguments */
    if (aead == NULL || inKey == NULL || inIV == NULL) {
        return BAD_FUNC_ARG;
    }

    /* setup aead context */
    XMEMSET(aead, 0, sizeof(ChaChaPoly_Aead));
    XMEMSET(authKey, 0, sizeof(authKey));
    aead->isEncrypt = isEncrypt ? 1 : 0;

    /* Initialize the ChaCha20 context (key and iv) */
    ret = wc_Chacha_SetKey(&aead->chacha, inKey,
        CHACHA20_POLY1305_AEAD_KEYSIZE);
    if (ret == 0) {
        ret = wc_Chacha_SetIV(&aead->chacha, inIV,
            CHACHA20_POLY1305_AEAD_INITIAL_COUNTER);
    }

    /* Create the Poly1305 key */
    if (ret == 0) {
        ret = wc_Chacha_Process(&aead->chacha, authKey, authKey,
            CHACHA20_POLY1305_AEAD_KEYSIZE);
    }

    /* Initialize Poly1305 context */
    if (ret == 0) {
        ret = wc_Poly1305SetKey(&aead->poly, authKey,
            CHACHA20_POLY1305_AEAD_KEYSIZE);
    }

    /* advance counter by 1 after creating Poly1305 key */
    if (ret == 0) {
        ret = wc_Chacha_SetIV(&aead->chacha, inIV,
            CHACHA20_POLY1305_AEAD_INITIAL_COUNTER + 1);
    }

    if (ret == 0) {
        aead->state = CHACHA20_POLY1305_STATE_READY;
    }

    return ret;
}

/* optional additional authentication data */
int wc_ChaCha20Poly1305_UpdateAad(ChaChaPoly_Aead* aead,
    const byte* inAAD, word32 inAADLen)
{
    int ret = 0;

    if (aead == NULL || (inAAD == NULL && inAADLen > 0)) {
        return BAD_FUNC_ARG;
    }
    if (aead->state != CHACHA20_POLY1305_STATE_READY &&
        aead->state != CHACHA20_POLY1305_STATE_AAD) {
        return BAD_STATE_E;
    }
    if (inAADLen > CHACHA20_POLY1305_MAX - aead->aadLen)
        return CHACHA_POLY_OVERFLOW;

    if (inAAD && inAADLen > 0) {
        ret = wc_Poly1305Update(&aead->poly, inAAD, inAADLen);
        if (ret == 0) {
            aead->aadLen += inAADLen;
            aead->state = CHACHA20_POLY1305_STATE_AAD;
        }
    }

    return ret;
}

/* inData and outData can be same pointer (inline) */
int wc_ChaCha20Poly1305_UpdateData(ChaChaPoly_Aead* aead,
    const byte* inData, byte* outData, word32 dataLen)
{
    int ret = 0;

    if (aead == NULL || inData == NULL || outData == NULL) {
        return BAD_FUNC_ARG;
    }
    if (aead->state != CHACHA20_POLY1305_STATE_READY &&
        aead->state != CHACHA20_POLY1305_STATE_AAD &&
        aead->state != CHACHA20_POLY1305_STATE_DATA) {
        return BAD_STATE_E;
    }
    if (dataLen > CHACHA20_POLY1305_MAX - aead->dataLen)
        return CHACHA_POLY_OVERFLOW;

    /* Pad the AAD */
    if (aead->state == CHACHA20_POLY1305_STATE_AAD) {
        ret = wc_Poly1305_Pad(&aead->poly, aead->aadLen);
    }

    /* advance state */
    aead->state = CHACHA20_POLY1305_STATE_DATA;

    /* Perform ChaCha20 encrypt/decrypt and Poly1305 auth calc */
    if (ret == 0) {
        if (aead->isEncrypt) {
            ret = wc_Chacha_Process(&aead->chacha, outData, inData, dataLen);
            if (ret == 0)
                ret = wc_Poly1305Update(&aead->poly, outData, dataLen);
        }
        else {
            ret = wc_Poly1305Update(&aead->poly, inData, dataLen);
            if (ret == 0)
                ret = wc_Chacha_Process(&aead->chacha, outData, inData, dataLen);
        }
    }
    if (ret == 0) {
        aead->dataLen += dataLen;
    }
    return ret;
}

int wc_ChaCha20Poly1305_Final(ChaChaPoly_Aead* aead,
    byte outAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE])
{
    int ret = 0;

    if (aead == NULL || outAuthTag == NULL) {
        return BAD_FUNC_ARG;
    }
    if (aead->state != CHACHA20_POLY1305_STATE_AAD &&
        aead->state != CHACHA20_POLY1305_STATE_DATA) {
        return BAD_STATE_E;
    }

    /* Pad the AAD - Make sure it is done */
    if (aead->state == CHACHA20_POLY1305_STATE_AAD) {
        ret = wc_Poly1305_Pad(&aead->poly, aead->aadLen);
    }

    /* Pad the plaintext/ciphertext to 16 bytes */
    if (ret == 0) {
        ret = wc_Poly1305_Pad(&aead->poly, aead->dataLen);
    }

    /* Add the aad length and plaintext/ciphertext length */
    if (ret == 0) {
        ret = wc_Poly1305_EncodeSizes(&aead->poly, aead->aadLen,
            aead->dataLen);
    }

    /* Finalize the auth tag */
    if (ret == 0) {
        ret = wc_Poly1305Final(&aead->poly, outAuthTag);
    }

    /* reset and cleanup sensitive context */
    ForceZero(aead, sizeof(ChaChaPoly_Aead));

    return ret;
}

#ifdef HAVE_XCHACHA

int wc_XChaCha20Poly1305_Init(
    ChaChaPoly_Aead *aead,
    const byte *ad, word32 ad_len,
    const byte *nonce, word32 nonce_len,
    const byte *key, word32 key_len,
    int isEncrypt)
{
    byte authKey[CHACHA20_POLY1305_AEAD_KEYSIZE];
    int ret;

    if ((ad == NULL) || (nonce == NULL) || (key == NULL))
        return BAD_FUNC_ARG;

    if ((key_len != CHACHA20_POLY1305_AEAD_KEYSIZE) ||
        (nonce_len != XCHACHA20_POLY1305_AEAD_NONCE_SIZE))
        return BAD_FUNC_ARG;

    if ((ret = wc_XChacha_SetKey(&aead->chacha,
                                 key, key_len,
                                 nonce, nonce_len,
                                 0 /* counter */)) < 0)
        return ret;

    XMEMSET(authKey, 0, sizeof authKey);

    /* Create the Poly1305 key */
    if ((ret = wc_Chacha_Process(&aead->chacha, authKey, authKey,
                                 (word32)sizeof authKey)) < 0)
        return ret;
    /* advance to start of the next ChaCha block. */
    wc_Chacha_purge_current_block(&aead->chacha);

    /* Initialize Poly1305 context */
    if ((ret = wc_Poly1305SetKey(&aead->poly, authKey,
                                 (word32)sizeof authKey)) < 0)
        return ret;

    if ((ret = wc_Poly1305Update(&aead->poly, ad, (word32)ad_len)) < 0)
        return ret;

    if ((ret = wc_Poly1305_Pad(&aead->poly, (word32)ad_len)) < 0)
        return ret;

    aead->isEncrypt = isEncrypt ? 1 : 0;
    aead->state = CHACHA20_POLY1305_STATE_AAD;

    return 0;
}

static WC_INLINE int wc_XChaCha20Poly1305_crypt_oneshot(
    byte *dst, const size_t dst_space,
    const byte *src, const size_t src_len,
    const byte *ad, const size_t ad_len,
    const byte *nonce, const size_t nonce_len,
    const byte *key, const size_t key_len,
    int isEncrypt)
{
    int ret;
    long int dst_len = isEncrypt ?
        (long int)src_len + POLY1305_DIGEST_SIZE :
        (long int)src_len - POLY1305_DIGEST_SIZE;
    const byte *src_i;
    byte *dst_i;
    size_t src_len_rem;
#if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_NO_MALLOC)
    ChaChaPoly_Aead *aead = (ChaChaPoly_Aead *)XMALLOC(sizeof *aead, NULL, DYNAMIC_TYPE_TMP_BUFFER);

    if (aead == NULL)
        return MEMORY_E;
#else
    ChaChaPoly_Aead aead_buf, *aead = &aead_buf;
#endif

    if ((dst == NULL) || (src == NULL)) {
        ret = BAD_FUNC_ARG;
        goto out;
    }

    if (dst_len < 0 || (long int)dst_space < dst_len) {
        ret = BUFFER_E;
        goto out;
    }

    if ((ret = wc_XChaCha20Poly1305_Init(aead, ad, (word32)ad_len,
                                         nonce, (word32)nonce_len,
                                         key, (word32)key_len, 1)) < 0)
        goto out;

#ifdef WOLFSSL_CHECK_MEM_ZERO
    wc_MemZero_Add("wc_XChaCha20Poly1305_crypt_oneshot aead", aead,
        sizeof(ChaChaPoly_Aead));
#endif

    /* process the input in 16k pieces to accommodate src_lens that don't fit in a word32,
     * and to exploit hot cache for the input data.
     */
    src_i = src;
    src_len_rem = isEncrypt ? src_len : (size_t)dst_len;
    dst_i = dst;
    while (src_len_rem > 0) {
        word32 this_src_len =
            (src_len_rem > 16384) ?
            16384 :
            (word32)src_len_rem;

        if ((ret = wc_Chacha_Process(&aead->chacha, dst_i, src_i, this_src_len)) < 0)
            goto out;

        if ((ret = wc_Poly1305Update(&aead->poly, isEncrypt ? dst_i : src_i, this_src_len)) < 0)
            goto out;

        src_len_rem -= (size_t)this_src_len;
        src_i += this_src_len;
        dst_i += this_src_len;
    }

    if (aead->poly.leftover) {
        if ((ret = wc_Poly1305_Pad(&aead->poly, (word32)aead->poly.leftover)) < 0)
            return ret;
    }

#ifdef WORD64_AVAILABLE
    ret = wc_Poly1305_EncodeSizes64(&aead->poly, ad_len, isEncrypt ? src_len : (size_t)dst_len);
#else
    ret = wc_Poly1305_EncodeSizes(&aead->poly, ad_len, isEncrypt ? src_len : (size_t)dst_len);
#endif
    if (ret < 0)
        goto out;

    if (isEncrypt)
        ret = wc_Poly1305Final(&aead->poly, dst + src_len);
    else {
        byte outAuthTag[POLY1305_DIGEST_SIZE];

        if ((ret = wc_Poly1305Final(&aead->poly, outAuthTag)) < 0)
            goto out;

        if (ConstantCompare(outAuthTag, src + dst_len, POLY1305_DIGEST_SIZE) != 0) {
            ret = MAC_CMP_FAILED_E;
            goto out;
        }
    }

  out:

    ForceZero(aead, sizeof *aead);

#if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_NO_MALLOC)
    XFREE(aead, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#elif defined(WOLFSSL_CHECK_MEM_ZERO)
    wc_MemZero_Check(aead, sizeof(ChaChaPoly_Aead));
#endif

    return ret;
}

int wc_XChaCha20Poly1305_Encrypt(
    byte *dst, const size_t dst_space,
    const byte *src, const size_t src_len,
    const byte *ad, const size_t ad_len,
    const byte *nonce, const size_t nonce_len,
    const byte *key, const size_t key_len)
{
    return wc_XChaCha20Poly1305_crypt_oneshot(dst, dst_space, src, src_len, ad, ad_len, nonce, nonce_len, key, key_len, 1);
}

int wc_XChaCha20Poly1305_Decrypt(
    byte *dst, const size_t dst_space,
    const byte *src, const size_t src_len,
    const byte *ad, const size_t ad_len,
    const byte *nonce, const size_t nonce_len,
    const byte *key, const size_t key_len)
{
    return wc_XChaCha20Poly1305_crypt_oneshot(dst, dst_space, src, src_len, ad, ad_len, nonce, nonce_len, key, key_len, 0);
}

#endif /* HAVE_XCHACHA */

#endif /* HAVE_CHACHA && HAVE_POLY1305 */

Coverage Report

Created: 2025-11-16 07:15

Line	Count	Source
1		/* chacha.c
2		*
3		* Copyright (C) 2006-2025 wolfSSL Inc.
4		*
5		* This file is part of wolfSSL.
6		*
7		* wolfSSL is free software; you can redistribute it and/or modify
8		* it under the terms of the GNU General Public License as published by
9		* the Free Software Foundation; either version 3 of the License, or
10		* (at your option) any later version.
11		*
12		* wolfSSL is distributed in the hope that it will be useful,
13		* but WITHOUT ANY WARRANTY; without even the implied warranty of
14		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15		* GNU General Public License for more details.
16		*
17		* You should have received a copy of the GNU General Public License
18		* along with this program; if not, write to the Free Software
19		* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
20		*/
21		/*
22
23		DESCRIPTION
24		This library contains implementation for the ChaCha20 stream cipher and
25		the Poly1305 authenticator, both as as combined-mode,
26		or Authenticated Encryption with Additional Data (AEAD) algorithm.
27
28		*/
29
30		#include <wolfssl/wolfcrypt/libwolfssl_sources.h>
31
32		#if defined(HAVE_CHACHA) && defined(HAVE_POLY1305)
33
34		#include <wolfssl/wolfcrypt/chacha20_poly1305.h>
35
36		#ifdef NO_INLINE
37		#include <wolfssl/wolfcrypt/misc.h>
38		#else
39		#define WOLFSSL_MISC_INCLUDED
40		#include <wolfcrypt/src/misc.c>
41		#endif
42
43	0	#define CHACHA20_POLY1305_AEAD_INITIAL_COUNTER 0
44		WOLFSSL_ABI
45		int wc_ChaCha20Poly1305_Encrypt(
46		const byte inKey[CHACHA20_POLY1305_AEAD_KEYSIZE],
47		const byte inIV[CHACHA20_POLY1305_AEAD_IV_SIZE],
48		const byte* inAAD, const word32 inAADLen,
49		const byte* inPlaintext, const word32 inPlaintextLen,
50		byte* outCiphertext,
51		byte outAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE])
52	0	{
53	0	int ret;
54	0	WC_DECLARE_VAR(aead, ChaChaPoly_Aead, 1, 0);
55
56		/* Validate function arguments */
57	0	if (!inKey \|\| !inIV \|\|
58	0	(inPlaintextLen > 0 && inPlaintext == NULL) \|\|
59	0	!outCiphertext \|\|
60	0	!outAuthTag)
61	0	{
62	0	return BAD_FUNC_ARG;
63	0	}
64
65	0	WC_ALLOC_VAR_EX(aead, ChaChaPoly_Aead, 1, NULL, DYNAMIC_TYPE_TMP_BUFFER,
66	0	return MEMORY_E);
67
68	0	ret = wc_ChaCha20Poly1305_Init(aead, inKey, inIV,
69	0	CHACHA20_POLY1305_AEAD_ENCRYPT);
70	0	if (ret == 0)
71	0	ret = wc_ChaCha20Poly1305_UpdateAad(aead, inAAD, inAADLen);
72	0	if (ret == 0)
73	0	ret = wc_ChaCha20Poly1305_UpdateData(aead, inPlaintext, outCiphertext,
74	0	inPlaintextLen);
75	0	if (ret == 0)
76	0	ret = wc_ChaCha20Poly1305_Final(aead, outAuthTag);
77
78	0	WC_FREE_VAR_EX(aead, NULL, DYNAMIC_TYPE_TMP_BUFFER);
79
80	0	return ret;
81	0	}
82
83		WOLFSSL_ABI
84		int wc_ChaCha20Poly1305_Decrypt(
85		const byte inKey[CHACHA20_POLY1305_AEAD_KEYSIZE],
86		const byte inIV[CHACHA20_POLY1305_AEAD_IV_SIZE],
87		const byte* inAAD, const word32 inAADLen,
88		const byte* inCiphertext, const word32 inCiphertextLen,
89		const byte inAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE],
90		byte* outPlaintext)
91	0	{
92	0	int ret;
93	0	WC_DECLARE_VAR(aead, ChaChaPoly_Aead, 1, 0);
94	0	byte calculatedAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE];
95
96		/* Validate function arguments */
97	0	if (!inKey \|\| !inIV \|\|
98	0	(inCiphertextLen > 0 && inCiphertext == NULL) \|\|
99	0	!inAuthTag \|\|
100	0	!outPlaintext)
101	0	{
102	0	return BAD_FUNC_ARG;
103	0	}
104
105	0	WC_ALLOC_VAR_EX(aead, ChaChaPoly_Aead, 1, NULL, DYNAMIC_TYPE_TMP_BUFFER,
106	0	return MEMORY_E);
107
108	0	XMEMSET(calculatedAuthTag, 0, sizeof(calculatedAuthTag));
109
110	0	ret = wc_ChaCha20Poly1305_Init(aead, inKey, inIV,
111	0	CHACHA20_POLY1305_AEAD_DECRYPT);
112	0	if (ret == 0)
113	0	ret = wc_ChaCha20Poly1305_UpdateAad(aead, inAAD, inAADLen);
114	0	if (ret == 0)
115	0	ret = wc_ChaCha20Poly1305_UpdateData(aead, inCiphertext, outPlaintext,
116	0	inCiphertextLen);
117	0	if (ret == 0)
118	0	ret = wc_ChaCha20Poly1305_Final(aead, calculatedAuthTag);
119	0	if (ret == 0)
120	0	ret = wc_ChaCha20Poly1305_CheckTag(inAuthTag, calculatedAuthTag);
121
122	0	WC_FREE_VAR_EX(aead, NULL, DYNAMIC_TYPE_TMP_BUFFER);
123
124	0	return ret;
125	0	}
126
127		int wc_ChaCha20Poly1305_CheckTag(
128		const byte authTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE],
129		const byte authTagChk[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE])
130	0	{
131	0	int ret = 0;
132	0	if (authTag == NULL \|\| authTagChk == NULL) {
133	0	return BAD_FUNC_ARG;
134	0	}
135	0	if (ConstantCompare(authTag, authTagChk,
136	0	CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE) != 0) {
137	0	ret = MAC_CMP_FAILED_E;
138	0	}
139	0	return ret;
140	0	}
141
142		int wc_ChaCha20Poly1305_Init(ChaChaPoly_Aead* aead,
143		const byte inKey[CHACHA20_POLY1305_AEAD_KEYSIZE],
144		const byte inIV[CHACHA20_POLY1305_AEAD_IV_SIZE],
145		int isEncrypt)
146	0	{
147	0	int ret;
148	0	byte authKey[CHACHA20_POLY1305_AEAD_KEYSIZE];
149
150		/* check arguments */
151	0	if (aead == NULL \|\| inKey == NULL \|\| inIV == NULL) {
152	0	return BAD_FUNC_ARG;
153	0	}
154
155		/* setup aead context */
156	0	XMEMSET(aead, 0, sizeof(ChaChaPoly_Aead));
157	0	XMEMSET(authKey, 0, sizeof(authKey));
158	0	aead->isEncrypt = isEncrypt ? 1 : 0;
159
160		/* Initialize the ChaCha20 context (key and iv) */
161	0	ret = wc_Chacha_SetKey(&aead->chacha, inKey,
162	0	CHACHA20_POLY1305_AEAD_KEYSIZE);
163	0	if (ret == 0) {
164	0	ret = wc_Chacha_SetIV(&aead->chacha, inIV,
165	0	CHACHA20_POLY1305_AEAD_INITIAL_COUNTER);
166	0	}
167
168		/* Create the Poly1305 key */
169	0	if (ret == 0) {
170	0	ret = wc_Chacha_Process(&aead->chacha, authKey, authKey,
171	0	CHACHA20_POLY1305_AEAD_KEYSIZE);
172	0	}
173
174		/* Initialize Poly1305 context */
175	0	if (ret == 0) {
176	0	ret = wc_Poly1305SetKey(&aead->poly, authKey,
177	0	CHACHA20_POLY1305_AEAD_KEYSIZE);
178	0	}
179
180		/* advance counter by 1 after creating Poly1305 key */
181	0	if (ret == 0) {
182	0	ret = wc_Chacha_SetIV(&aead->chacha, inIV,
183	0	CHACHA20_POLY1305_AEAD_INITIAL_COUNTER + 1);
184	0	}
185
186	0	if (ret == 0) {
187	0	aead->state = CHACHA20_POLY1305_STATE_READY;
188	0	}
189
190	0	return ret;
191	0	}
192
193		/* optional additional authentication data */
194		int wc_ChaCha20Poly1305_UpdateAad(ChaChaPoly_Aead* aead,
195		const byte* inAAD, word32 inAADLen)
196	0	{
197	0	int ret = 0;
198
199	0	if (aead == NULL \|\| (inAAD == NULL && inAADLen > 0)) {
200	0	return BAD_FUNC_ARG;
201	0	}
202	0	if (aead->state != CHACHA20_POLY1305_STATE_READY &&
203	0	aead->state != CHACHA20_POLY1305_STATE_AAD) {
204	0	return BAD_STATE_E;
205	0	}
206	0	if (inAADLen > CHACHA20_POLY1305_MAX - aead->aadLen)
207	0	return CHACHA_POLY_OVERFLOW;
208
209	0	if (inAAD && inAADLen > 0) {
210	0	ret = wc_Poly1305Update(&aead->poly, inAAD, inAADLen);
211	0	if (ret == 0) {
212	0	aead->aadLen += inAADLen;
213	0	aead->state = CHACHA20_POLY1305_STATE_AAD;
214	0	}
215	0	}
216
217	0	return ret;
218	0	}
219
220		/* inData and outData can be same pointer (inline) */
221		int wc_ChaCha20Poly1305_UpdateData(ChaChaPoly_Aead* aead,
222		const byte* inData, byte* outData, word32 dataLen)
223	0	{
224	0	int ret = 0;
225
226	0	if (aead == NULL \|\| inData == NULL \|\| outData == NULL) {
227	0	return BAD_FUNC_ARG;
228	0	}
229	0	if (aead->state != CHACHA20_POLY1305_STATE_READY &&
230	0	aead->state != CHACHA20_POLY1305_STATE_AAD &&
231	0	aead->state != CHACHA20_POLY1305_STATE_DATA) {
232	0	return BAD_STATE_E;
233	0	}
234	0	if (dataLen > CHACHA20_POLY1305_MAX - aead->dataLen)
235	0	return CHACHA_POLY_OVERFLOW;
236
237		/* Pad the AAD */
238	0	if (aead->state == CHACHA20_POLY1305_STATE_AAD) {
239	0	ret = wc_Poly1305_Pad(&aead->poly, aead->aadLen);
240	0	}
241
242		/* advance state */
243	0	aead->state = CHACHA20_POLY1305_STATE_DATA;
244
245		/* Perform ChaCha20 encrypt/decrypt and Poly1305 auth calc */
246	0	if (ret == 0) {
247	0	if (aead->isEncrypt) {
248	0	ret = wc_Chacha_Process(&aead->chacha, outData, inData, dataLen);
249	0	if (ret == 0)
250	0	ret = wc_Poly1305Update(&aead->poly, outData, dataLen);
251	0	}
252	0	else {
253	0	ret = wc_Poly1305Update(&aead->poly, inData, dataLen);
254	0	if (ret == 0)
255	0	ret = wc_Chacha_Process(&aead->chacha, outData, inData, dataLen);
256	0	}
257	0	}
258	0	if (ret == 0) {
259	0	aead->dataLen += dataLen;
260	0	}
261	0	return ret;
262	0	}
263
264		int wc_ChaCha20Poly1305_Final(ChaChaPoly_Aead* aead,
265		byte outAuthTag[CHACHA20_POLY1305_AEAD_AUTHTAG_SIZE])
266	0	{
267	0	int ret = 0;
268
269	0	if (aead == NULL \|\| outAuthTag == NULL) {
270	0	return BAD_FUNC_ARG;
271	0	}
272	0	if (aead->state != CHACHA20_POLY1305_STATE_AAD &&
273	0	aead->state != CHACHA20_POLY1305_STATE_DATA) {
274	0	return BAD_STATE_E;
275	0	}
276
277		/* Pad the AAD - Make sure it is done */
278	0	if (aead->state == CHACHA20_POLY1305_STATE_AAD) {
279	0	ret = wc_Poly1305_Pad(&aead->poly, aead->aadLen);
280	0	}
281
282		/* Pad the plaintext/ciphertext to 16 bytes */
283	0	if (ret == 0) {
284	0	ret = wc_Poly1305_Pad(&aead->poly, aead->dataLen);
285	0	}
286
287		/* Add the aad length and plaintext/ciphertext length */
288	0	if (ret == 0) {
289	0	ret = wc_Poly1305_EncodeSizes(&aead->poly, aead->aadLen,
290	0	aead->dataLen);
291	0	}
292
293		/* Finalize the auth tag */
294	0	if (ret == 0) {
295	0	ret = wc_Poly1305Final(&aead->poly, outAuthTag);
296	0	}
297
298		/* reset and cleanup sensitive context */
299	0	ForceZero(aead, sizeof(ChaChaPoly_Aead));
300
301	0	return ret;
302	0	}
303
304		#ifdef HAVE_XCHACHA
305
306		int wc_XChaCha20Poly1305_Init(
307		ChaChaPoly_Aead *aead,
308		const byte *ad, word32 ad_len,
309		const byte *nonce, word32 nonce_len,
310		const byte *key, word32 key_len,
311		int isEncrypt)
312	0	{
313	0	byte authKey[CHACHA20_POLY1305_AEAD_KEYSIZE];
314	0	int ret;
315
316	0	if ((ad == NULL) \|\| (nonce == NULL) \|\| (key == NULL))
317	0	return BAD_FUNC_ARG;
318
319	0	if ((key_len != CHACHA20_POLY1305_AEAD_KEYSIZE) \|\|
320	0	(nonce_len != XCHACHA20_POLY1305_AEAD_NONCE_SIZE))
321	0	return BAD_FUNC_ARG;
322
323	0	if ((ret = wc_XChacha_SetKey(&aead->chacha,
324	0	key, key_len,
325	0	nonce, nonce_len,
326	0	0 /* counter */)) < 0)
327	0	return ret;
328
329	0	XMEMSET(authKey, 0, sizeof authKey);
330
331		/* Create the Poly1305 key */
332	0	if ((ret = wc_Chacha_Process(&aead->chacha, authKey, authKey,
333	0	(word32)sizeof authKey)) < 0)
334	0	return ret;
335		/* advance to start of the next ChaCha block. */
336	0	wc_Chacha_purge_current_block(&aead->chacha);
337
338		/* Initialize Poly1305 context */
339	0	if ((ret = wc_Poly1305SetKey(&aead->poly, authKey,
340	0	(word32)sizeof authKey)) < 0)
341	0	return ret;
342
343	0	if ((ret = wc_Poly1305Update(&aead->poly, ad, (word32)ad_len)) < 0)
344	0	return ret;
345
346	0	if ((ret = wc_Poly1305_Pad(&aead->poly, (word32)ad_len)) < 0)
347	0	return ret;
348
349	0	aead->isEncrypt = isEncrypt ? 1 : 0;
350	0	aead->state = CHACHA20_POLY1305_STATE_AAD;
351
352	0	return 0;
353	0	}
354
355		static WC_INLINE int wc_XChaCha20Poly1305_crypt_oneshot(
356		byte *dst, const size_t dst_space,
357		const byte *src, const size_t src_len,
358		const byte *ad, const size_t ad_len,
359		const byte *nonce, const size_t nonce_len,
360		const byte *key, const size_t key_len,
361		int isEncrypt)
362	0	{
363	0	int ret;
364	0	long int dst_len = isEncrypt ?
365	0	(long int)src_len + POLY1305_DIGEST_SIZE :
366	0	(long int)src_len - POLY1305_DIGEST_SIZE;
367	0	const byte *src_i;
368	0	byte *dst_i;
369	0	size_t src_len_rem;
370	0	#if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_NO_MALLOC)
371	0	ChaChaPoly_Aead aead = (ChaChaPoly_Aead )XMALLOC(sizeof *aead, NULL, DYNAMIC_TYPE_TMP_BUFFER);
372
373	0	if (aead == NULL)
374	0	return MEMORY_E;
375		#else
376		ChaChaPoly_Aead aead_buf, *aead = &aead_buf;
377		#endif
378
379	0	if ((dst == NULL) \|\| (src == NULL)) {
380	0	ret = BAD_FUNC_ARG;
381	0	goto out;
382	0	}
383
384	0	if (dst_len < 0 \|\| (long int)dst_space < dst_len) {
385	0	ret = BUFFER_E;
386	0	goto out;
387	0	}
388
389	0	if ((ret = wc_XChaCha20Poly1305_Init(aead, ad, (word32)ad_len,
390	0	nonce, (word32)nonce_len,
391	0	key, (word32)key_len, 1)) < 0)
392	0	goto out;
393
394		#ifdef WOLFSSL_CHECK_MEM_ZERO
395		wc_MemZero_Add("wc_XChaCha20Poly1305_crypt_oneshot aead", aead,
396		sizeof(ChaChaPoly_Aead));
397		#endif
398
399		/* process the input in 16k pieces to accommodate src_lens that don't fit in a word32,
400		* and to exploit hot cache for the input data.
401		*/
402	0	src_i = src;
403	0	src_len_rem = isEncrypt ? src_len : (size_t)dst_len;
404	0	dst_i = dst;
405	0	while (src_len_rem > 0) {
406	0	word32 this_src_len =
407	0	(src_len_rem > 16384) ?
408	0	16384 :
409	0	(word32)src_len_rem;
410
411	0	if ((ret = wc_Chacha_Process(&aead->chacha, dst_i, src_i, this_src_len)) < 0)
412	0	goto out;
413
414	0	if ((ret = wc_Poly1305Update(&aead->poly, isEncrypt ? dst_i : src_i, this_src_len)) < 0)
415	0	goto out;
416
417	0	src_len_rem -= (size_t)this_src_len;
418	0	src_i += this_src_len;
419	0	dst_i += this_src_len;
420	0	}
421
422	0	if (aead->poly.leftover) {
423	0	if ((ret = wc_Poly1305_Pad(&aead->poly, (word32)aead->poly.leftover)) < 0)
424	0	return ret;
425	0	}
426
427	0	#ifdef WORD64_AVAILABLE
428	0	ret = wc_Poly1305_EncodeSizes64(&aead->poly, ad_len, isEncrypt ? src_len : (size_t)dst_len);
429		#else
430		ret = wc_Poly1305_EncodeSizes(&aead->poly, ad_len, isEncrypt ? src_len : (size_t)dst_len);
431		#endif
432	0	if (ret < 0)
433	0	goto out;
434
435	0	if (isEncrypt)
436	0	ret = wc_Poly1305Final(&aead->poly, dst + src_len);
437	0	else {
438	0	byte outAuthTag[POLY1305_DIGEST_SIZE];
439
440	0	if ((ret = wc_Poly1305Final(&aead->poly, outAuthTag)) < 0)
441	0	goto out;
442
443	0	if (ConstantCompare(outAuthTag, src + dst_len, POLY1305_DIGEST_SIZE) != 0) {
444	0	ret = MAC_CMP_FAILED_E;
445	0	goto out;
446	0	}
447	0	}
448
449	0	out:
450
451	0	ForceZero(aead, sizeof *aead);
452
453	0	#if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_NO_MALLOC)
454	0	XFREE(aead, NULL, DYNAMIC_TYPE_TMP_BUFFER);
455		#elif defined(WOLFSSL_CHECK_MEM_ZERO)
456		wc_MemZero_Check(aead, sizeof(ChaChaPoly_Aead));
457		#endif
458
459	0	return ret;
460	0	}
461
462		int wc_XChaCha20Poly1305_Encrypt(
463		byte *dst, const size_t dst_space,
464		const byte *src, const size_t src_len,
465		const byte *ad, const size_t ad_len,
466		const byte *nonce, const size_t nonce_len,
467		const byte *key, const size_t key_len)
468	0	{
469	0	return wc_XChaCha20Poly1305_crypt_oneshot(dst, dst_space, src, src_len, ad, ad_len, nonce, nonce_len, key, key_len, 1);
470	0	}
471
472		int wc_XChaCha20Poly1305_Decrypt(
473		byte *dst, const size_t dst_space,
474		const byte *src, const size_t src_len,
475		const byte *ad, const size_t ad_len,
476		const byte *nonce, const size_t nonce_len,
477		const byte *key, const size_t key_len)
478	0	{
479	0	return wc_XChaCha20Poly1305_crypt_oneshot(dst, dst_space, src, src_len, ad, ad_len, nonce, nonce_len, key, key_len, 0);
480	0	}
481
482		#endif /* HAVE_XCHACHA */
483
484		#endif /* HAVE_CHACHA && HAVE_POLY1305 */