/src/libzip/lib/zip_winzip_aes.c

Source (jump to first uncovered line)
/*
  zip_winzip_aes.c -- Winzip AES de/encryption backend routines
  Copyright (C) 2017-2022 Dieter Baron and Thomas Klausner

  This file is part of libzip, a library to manipulate ZIP archives.
  The authors can be contacted at <info@libzip.org>

  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. The names of the authors may not be used to endorse or promote
  products derived from this software without specific prior
  written permission.

  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
  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 AUTHORS 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 "zipint.h"

#include "zip_crypto.h"

#include <stdlib.h>
#include <string.h>


#define MAX_KEY_LENGTH 256
#define PBKDF2_ITERATIONS 1000

struct _zip_winzip_aes {
    _zip_crypto_aes_t *aes;
    _zip_crypto_hmac_t *hmac;
    zip_uint8_t counter[ZIP_CRYPTO_AES_BLOCK_LENGTH];
    zip_uint8_t pad[ZIP_CRYPTO_AES_BLOCK_LENGTH];
    int pad_offset;
};

static bool
aes_crypt(zip_winzip_aes_t *ctx, zip_uint8_t *data, zip_uint64_t length) {
    zip_uint64_t i, j;

    for (i = 0; i < length; i++) {
        if (ctx->pad_offset == AES_BLOCK_SIZE) {
            for (j = 0; j < 8; j++) {
                ctx->counter[j]++;
                if (ctx->counter[j] != 0) {
                    break;
                }
            }
            if (!_zip_crypto_aes_encrypt_block(ctx->aes, ctx->counter, ctx->pad)) {
                return false;
            }
            ctx->pad_offset = 0;
        }
        data[i] ^= ctx->pad[ctx->pad_offset++];
    }

    return true;
}


zip_winzip_aes_t *
_zip_winzip_aes_new(const zip_uint8_t *password, zip_uint64_t password_length, const zip_uint8_t *salt, zip_uint16_t encryption_method, zip_uint8_t *password_verify, zip_error_t *error) {
    zip_winzip_aes_t *ctx;
    zip_uint8_t buffer[2 * (MAX_KEY_LENGTH / 8) + WINZIP_AES_PASSWORD_VERIFY_LENGTH];
    zip_uint16_t key_size = 0; /* in bits */
    zip_uint16_t key_length;   /* in bytes */

    switch (encryption_method) {
    case ZIP_EM_AES_128:
        key_size = 128;
        break;
    case ZIP_EM_AES_192:
        key_size = 192;
        break;
    case ZIP_EM_AES_256:
        key_size = 256;
        break;
    }

    if (key_size == 0 || salt == NULL || password == NULL || password_length == 0) {
        zip_error_set(error, ZIP_ER_INVAL, 0);
        return NULL;
    }

    key_length = key_size / 8;

    if ((ctx = (zip_winzip_aes_t *)malloc(sizeof(*ctx))) == NULL) {
        zip_error_set(error, ZIP_ER_MEMORY, 0);
        return NULL;
    }

    memset(ctx->counter, 0, sizeof(ctx->counter));
    ctx->pad_offset = ZIP_CRYPTO_AES_BLOCK_LENGTH;

    if (!_zip_crypto_pbkdf2(password, password_length, salt, key_length / 2, PBKDF2_ITERATIONS, buffer, 2 * key_length + WINZIP_AES_PASSWORD_VERIFY_LENGTH)) {
        free(ctx);
        return NULL;
    }

    if ((ctx->aes = _zip_crypto_aes_new(buffer, key_size, error)) == NULL) {
        _zip_crypto_clear(ctx, sizeof(*ctx));
        free(ctx);
        return NULL;
    }
    if ((ctx->hmac = _zip_crypto_hmac_new(buffer + key_length, key_length, error)) == NULL) {
        _zip_crypto_aes_free(ctx->aes);
        free(ctx);
        return NULL;
    }

    if (password_verify) {
        (void)memcpy_s(password_verify, WINZIP_AES_PASSWORD_VERIFY_LENGTH, buffer + (2 * key_size / 8), WINZIP_AES_PASSWORD_VERIFY_LENGTH);
    }

    return ctx;
}


bool
_zip_winzip_aes_encrypt(zip_winzip_aes_t *ctx, zip_uint8_t *data, zip_uint64_t length) {
    return aes_crypt(ctx, data, length) && _zip_crypto_hmac(ctx->hmac, data, length);
}


bool
_zip_winzip_aes_decrypt(zip_winzip_aes_t *ctx, zip_uint8_t *data, zip_uint64_t length) {
    return _zip_crypto_hmac(ctx->hmac, data, length) && aes_crypt(ctx, data, length);
}


bool
_zip_winzip_aes_finish(zip_winzip_aes_t *ctx, zip_uint8_t *hmac) {
    return _zip_crypto_hmac_output(ctx->hmac, hmac);
}


void
_zip_winzip_aes_free(zip_winzip_aes_t *ctx) {
    if (ctx == NULL) {
        return;
    }

    _zip_crypto_aes_free(ctx->aes);
    _zip_crypto_hmac_free(ctx->hmac);
    free(ctx);
}

Line	Count	Source (jump to first uncovered line)
1		/*
2		zip_winzip_aes.c -- Winzip AES de/encryption backend routines
3		Copyright (C) 2017-2022 Dieter Baron and Thomas Klausner
4
5		This file is part of libzip, a library to manipulate ZIP archives.
6		The authors can be contacted at <info@libzip.org>
7
8		Redistribution and use in source and binary forms, with or without
9		modification, are permitted provided that the following conditions
10		are met:
11		1. Redistributions of source code must retain the above copyright
12		notice, this list of conditions and the following disclaimer.
13		2. Redistributions in binary form must reproduce the above copyright
14		notice, this list of conditions and the following disclaimer in
15		the documentation and/or other materials provided with the
16		distribution.
17		3. The names of the authors may not be used to endorse or promote
18		products derived from this software without specific prior
19		written permission.
20
21		THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
22		OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23		WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24		ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
25		DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26		DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27		GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28		INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
29		IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30		OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
31		IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32		*/
33
34		#include "zipint.h"
35
36		#include "zip_crypto.h"
37
38		#include <stdlib.h>
39		#include <string.h>
40
41
42		#define MAX_KEY_LENGTH 256
43		#define PBKDF2_ITERATIONS 1000
44
45		struct _zip_winzip_aes {
46		_zip_crypto_aes_t *aes;
47		_zip_crypto_hmac_t *hmac;
48		zip_uint8_t counter[ZIP_CRYPTO_AES_BLOCK_LENGTH];
49		zip_uint8_t pad[ZIP_CRYPTO_AES_BLOCK_LENGTH];
50		int pad_offset;
51		};
52
53		static bool
54	11.0k	aes_crypt(zip_winzip_aes_t ctx, zip_uint8_t data, zip_uint64_t length) {
55	11.0k	zip_uint64_t i, j;
56
57	85.6M	for (i = 0; i < length; i++) {
58	85.6M	if (ctx->pad_offset == AES_BLOCK_SIZE) {
59	5.37M	for (j = 0; j < 8; j++) {
60	5.37M	ctx->counter[j]++;
61	5.37M	if (ctx->counter[j] != 0) {
62	5.35M	break;
63	5.35M	}
64	5.37M	}
65	5.35M	if (!_zip_crypto_aes_encrypt_block(ctx->aes, ctx->counter, ctx->pad)) {
66	0	return false;
67	0	}
68	5.35M	ctx->pad_offset = 0;
69	5.35M	}
70	85.6M	data[i] ^= ctx->pad[ctx->pad_offset++];
71	85.6M	}
72
73	11.0k	return true;
74	11.0k	}
75
76
77		zip_winzip_aes_t *
78	921	_zip_winzip_aes_new(const zip_uint8_t password, zip_uint64_t password_length, const zip_uint8_t salt, zip_uint16_t encryption_method, zip_uint8_t password_verify, zip_error_t error) {
79	921	zip_winzip_aes_t *ctx;
80	921	zip_uint8_t buffer[2 * (MAX_KEY_LENGTH / 8) + WINZIP_AES_PASSWORD_VERIFY_LENGTH];
81	921	zip_uint16_t key_size = 0; /* in bits */
82	921	zip_uint16_t key_length; /* in bytes */
83
84	921	switch (encryption_method) {
85	290	case ZIP_EM_AES_128:
86	290	key_size = 128;
87	290	break;
88	30	case ZIP_EM_AES_192:
89	30	key_size = 192;
90	30	break;
91	601	case ZIP_EM_AES_256:
92	601	key_size = 256;
93	601	break;
94	921	}
95
96	921	if (key_size == 0 \|\| salt == NULL \|\| password == NULL \|\| password_length == 0) {
97	0	zip_error_set(error, ZIP_ER_INVAL, 0);
98	0	return NULL;
99	0	}
100
101	921	key_length = key_size / 8;
102
103	921	if ((ctx = (zip_winzip_aes_t )malloc(sizeof(ctx))) == NULL) {
104	0	zip_error_set(error, ZIP_ER_MEMORY, 0);
105	0	return NULL;
106	0	}
107
108	921	memset(ctx->counter, 0, sizeof(ctx->counter));
109	921	ctx->pad_offset = ZIP_CRYPTO_AES_BLOCK_LENGTH;
110
111	921	if (!_zip_crypto_pbkdf2(password, password_length, salt, key_length / 2, PBKDF2_ITERATIONS, buffer, 2 * key_length + WINZIP_AES_PASSWORD_VERIFY_LENGTH)) {
112	0	free(ctx);
113	0	return NULL;
114	0	}
115
116	921	if ((ctx->aes = _zip_crypto_aes_new(buffer, key_size, error)) == NULL) {
117	0	_zip_crypto_clear(ctx, sizeof(*ctx));
118	0	free(ctx);
119	0	return NULL;
120	0	}
121	921	if ((ctx->hmac = _zip_crypto_hmac_new(buffer + key_length, key_length, error)) == NULL) {
122	0	_zip_crypto_aes_free(ctx->aes);
123	0	free(ctx);
124	0	return NULL;
125	0	}
126
127	921	if (password_verify) {
128	921	(void)memcpy_s(password_verify, WINZIP_AES_PASSWORD_VERIFY_LENGTH, buffer + (2 * key_size / 8), WINZIP_AES_PASSWORD_VERIFY_LENGTH);
129	921	}
130
131	921	return ctx;
132	921	}
133
134
135		bool
136	9.54k	_zip_winzip_aes_encrypt(zip_winzip_aes_t ctx, zip_uint8_t data, zip_uint64_t length) {
137	9.54k	return aes_crypt(ctx, data, length) && _zip_crypto_hmac(ctx->hmac, data, length);
138	9.54k	}
139
140
141		bool
142	1.50k	_zip_winzip_aes_decrypt(zip_winzip_aes_t ctx, zip_uint8_t data, zip_uint64_t length) {
143	1.50k	return _zip_crypto_hmac(ctx->hmac, data, length) && aes_crypt(ctx, data, length);
144	1.50k	}
145
146
147		bool
148	619	_zip_winzip_aes_finish(zip_winzip_aes_t ctx, zip_uint8_t hmac) {
149	619	return _zip_crypto_hmac_output(ctx->hmac, hmac);
150	619	}
151
152
153		void
154	1.66k	_zip_winzip_aes_free(zip_winzip_aes_t *ctx) {
155	1.66k	if (ctx == NULL) {
156	743	return;
157	743	}
158
159	921	_zip_crypto_aes_free(ctx->aes);
160	921	_zip_crypto_hmac_free(ctx->hmac);
161	921	free(ctx);
162	921	}

Coverage Report

Created: 2025-07-11 06:24