Coverage Report

Created: 2025-06-13 06:56

/src/openssl/providers/implementations/macs/kmac_prov.c
Line
Count
Source (jump to first uncovered line)
1
/*
2
 * Copyright 2018-2024 The OpenSSL Project Authors. All Rights Reserved.
3
 *
4
 * Licensed under the Apache License 2.0 (the "License").  You may not use
5
 * this file except in compliance with the License.  You can obtain a copy
6
 * in the file LICENSE in the source distribution or at
7
 * https://www.openssl.org/source/license.html
8
 */
9
10
/*
11
 * See SP800-185 "Appendix A - KMAC, .... in Terms of Keccak[c]"
12
 *
13
 * Inputs are:
14
 *    K = Key                  (len(K) < 2^2040 bits)
15
 *    X = Input
16
 *    L = Output length        (0 <= L < 2^2040 bits)
17
 *    S = Customization String Default="" (len(S) < 2^2040 bits)
18
 *
19
 * KMAC128(K, X, L, S)
20
 * {
21
 *     newX = bytepad(encode_string(K), 168) ||  X || right_encode(L).
22
 *     T = bytepad(encode_string("KMAC") || encode_string(S), 168).
23
 *     return KECCAK[256](T || newX || 00, L).
24
 * }
25
 *
26
 * KMAC256(K, X, L, S)
27
 * {
28
 *     newX = bytepad(encode_string(K), 136) ||  X || right_encode(L).
29
 *     T = bytepad(encode_string("KMAC") || encode_string(S), 136).
30
 *     return KECCAK[512](T || newX || 00, L).
31
 * }
32
 *
33
 * KMAC128XOF(K, X, L, S)
34
 * {
35
 *     newX = bytepad(encode_string(K), 168) ||  X || right_encode(0).
36
 *     T = bytepad(encode_string("KMAC") || encode_string(S), 168).
37
 *     return KECCAK[256](T || newX || 00, L).
38
 * }
39
 *
40
 * KMAC256XOF(K, X, L, S)
41
 * {
42
 *     newX = bytepad(encode_string(K), 136) ||  X || right_encode(0).
43
 *     T = bytepad(encode_string("KMAC") || encode_string(S), 136).
44
 *     return KECCAK[512](T || newX || 00, L).
45
 * }
46
 *
47
 */
48
49
#include <stdlib.h>
50
#include <string.h>
51
#include <openssl/core_dispatch.h>
52
#include <openssl/core_names.h>
53
#include <openssl/params.h>
54
#include <openssl/evp.h>
55
#include <openssl/err.h>
56
#include <openssl/proverr.h>
57
#include <openssl/fips_names.h>
58
#include "prov/securitycheck.h"
59
#include "prov/implementations.h"
60
#include "prov/provider_ctx.h"
61
#include "prov/provider_util.h"
62
#include "prov/providercommon.h"
63
#include "internal/cryptlib.h" /* ossl_assert */
64
65
/*
66
 * Forward declaration of everything implemented here.  This is not strictly
67
 * necessary for the compiler, but provides an assurance that the signatures
68
 * of the functions in the dispatch table are correct.
69
 */
70
static OSSL_FUNC_mac_newctx_fn kmac128_new;
71
static OSSL_FUNC_mac_newctx_fn kmac256_new;
72
static OSSL_FUNC_mac_dupctx_fn kmac_dup;
73
static OSSL_FUNC_mac_freectx_fn kmac_free;
74
static OSSL_FUNC_mac_gettable_ctx_params_fn kmac_gettable_ctx_params;
75
static OSSL_FUNC_mac_get_ctx_params_fn kmac_get_ctx_params;
76
static OSSL_FUNC_mac_settable_ctx_params_fn kmac_settable_ctx_params;
77
static OSSL_FUNC_mac_set_ctx_params_fn kmac_set_ctx_params;
78
static OSSL_FUNC_mac_init_fn kmac_init;
79
static OSSL_FUNC_mac_update_fn kmac_update;
80
static OSSL_FUNC_mac_final_fn kmac_final;
81
82
#define KMAC_MAX_BLOCKSIZE ((1600 - 128 * 2) / 8) /* 168 */
83
84
/*
85
 * Length encoding will be  a 1 byte size + length in bits (3 bytes max)
86
 * This gives a range of 0..0XFFFFFF bits = 2097151 bytes).
87
 */
88
0
#define KMAC_MAX_OUTPUT_LEN (0xFFFFFF / 8)
89
#define KMAC_MAX_ENCODED_HEADER_LEN (1 + 3)
90
91
/*
92
 * Restrict the maximum length of the customisation string.  This must not
93
 * exceed 64 bits = 8k bytes.
94
 */
95
0
#define KMAC_MAX_CUSTOM 512
96
97
/* Maximum size of encoded custom string */
98
#define KMAC_MAX_CUSTOM_ENCODED (KMAC_MAX_CUSTOM + KMAC_MAX_ENCODED_HEADER_LEN)
99
100
/* Maximum key size in bytes = 512 (4096 bits) */
101
0
#define KMAC_MAX_KEY 512
102
0
#define KMAC_MIN_KEY 4
103
104
/*
105
 * Maximum Encoded Key size will be padded to a multiple of the blocksize
106
 * i.e KMAC_MAX_KEY + KMAC_MAX_ENCODED_HEADER_LEN = 512 + 4
107
 * Padded to a multiple of KMAC_MAX_BLOCKSIZE
108
 */
109
#define KMAC_MAX_KEY_ENCODED (KMAC_MAX_BLOCKSIZE * 4)
110
111
/* Fixed value of encode_string("KMAC") */
112
static const unsigned char kmac_string[] = {
113
    0x01, 0x20, 0x4B, 0x4D, 0x41, 0x43
114
};
115
116
#define KMAC_FLAG_XOF_MODE          1
117
118
struct kmac_data_st {
119
    void  *provctx;
120
    EVP_MD_CTX *ctx;
121
    PROV_DIGEST digest;
122
    size_t out_len;
123
    size_t key_len;
124
    size_t custom_len;
125
    /* If xof_mode = 1 then we use right_encode(0) */
126
    int xof_mode;
127
    /* key and custom are stored in encoded form */
128
    unsigned char key[KMAC_MAX_KEY_ENCODED];
129
    unsigned char custom[KMAC_MAX_CUSTOM_ENCODED];
130
#ifdef FIPS_MODULE
131
    /*
132
     * 'internal' is set to 1 if KMAC is used inside another algorithm such as a
133
     * KDF. In this case it is the parent algorithm that is responsible for
134
     * performing any conditional FIPS indicator related checks for KMAC.
135
     */
136
    int internal;
137
#endif
138
    OSSL_FIPS_IND_DECLARE
139
};
140
141
static int encode_string(unsigned char *out, size_t out_max_len, size_t *out_len,
142
                         const unsigned char *in, size_t in_len);
143
static int right_encode(unsigned char *out, size_t out_max_len, size_t *out_len,
144
                        size_t bits);
145
static int bytepad(unsigned char *out, size_t *out_len,
146
                   const unsigned char *in1, size_t in1_len,
147
                   const unsigned char *in2, size_t in2_len,
148
                   size_t w);
149
static int kmac_bytepad_encode_key(unsigned char *out, size_t out_max_len,
150
                                   size_t *out_len,
151
                                   const unsigned char *in, size_t in_len,
152
                                   size_t w);
153
154
static void kmac_free(void *vmacctx)
155
0
{
156
0
    struct kmac_data_st *kctx = vmacctx;
157
158
0
    if (kctx != NULL) {
159
0
        EVP_MD_CTX_free(kctx->ctx);
160
0
        ossl_prov_digest_reset(&kctx->digest);
161
0
        OPENSSL_cleanse(kctx->key, kctx->key_len);
162
0
        OPENSSL_cleanse(kctx->custom, kctx->custom_len);
163
0
        OPENSSL_free(kctx);
164
0
    }
165
0
}
166
167
/*
168
 * We have KMAC implemented as a hash, which we can use instead of
169
 * reimplementing the EVP functionality with direct use of
170
 * keccak_mac_init() and friends.
171
 */
172
static struct kmac_data_st *kmac_new(void *provctx)
173
0
{
174
0
    struct kmac_data_st *kctx;
175
176
0
    if (!ossl_prov_is_running())
177
0
        return NULL;
178
179
0
    if ((kctx = OPENSSL_zalloc(sizeof(*kctx))) == NULL
180
0
            || (kctx->ctx = EVP_MD_CTX_new()) == NULL) {
181
0
        kmac_free(kctx);
182
0
        return NULL;
183
0
    }
184
0
    kctx->provctx = provctx;
185
0
    OSSL_FIPS_IND_INIT(kctx)
186
0
    return kctx;
187
0
}
188
189
static void *kmac_fetch_new(void *provctx, const OSSL_PARAM *params)
190
0
{
191
0
    struct kmac_data_st *kctx = kmac_new(provctx);
192
0
    int md_size;
193
194
0
    if (kctx == NULL)
195
0
        return 0;
196
0
    if (!ossl_prov_digest_load_from_params(&kctx->digest, params,
197
0
                                      PROV_LIBCTX_OF(provctx))) {
198
0
        kmac_free(kctx);
199
0
        return 0;
200
0
    }
201
202
0
    md_size = EVP_MD_get_size(ossl_prov_digest_md(&kctx->digest));
203
0
    if (md_size <= 0) {
204
0
        kmac_free(kctx);
205
0
        return 0;
206
0
    }
207
0
    kctx->out_len = (size_t)md_size;
208
0
    return kctx;
209
0
}
210
211
static void *kmac128_new(void *provctx)
212
0
{
213
0
    static const OSSL_PARAM kmac128_params[] = {
214
0
        OSSL_PARAM_utf8_string("digest", OSSL_DIGEST_NAME_KECCAK_KMAC128,
215
0
                               sizeof(OSSL_DIGEST_NAME_KECCAK_KMAC128)),
216
0
        OSSL_PARAM_END
217
0
    };
218
0
    return kmac_fetch_new(provctx, kmac128_params);
219
0
}
220
221
static void *kmac256_new(void *provctx)
222
0
{
223
0
    static const OSSL_PARAM kmac256_params[] = {
224
0
        OSSL_PARAM_utf8_string("digest", OSSL_DIGEST_NAME_KECCAK_KMAC256,
225
0
                               sizeof(OSSL_DIGEST_NAME_KECCAK_KMAC256)),
226
0
        OSSL_PARAM_END
227
0
    };
228
0
    return kmac_fetch_new(provctx, kmac256_params);
229
0
}
230
231
static void *kmac_dup(void *vsrc)
232
0
{
233
0
    struct kmac_data_st *src = vsrc;
234
0
    struct kmac_data_st *dst;
235
236
0
    if (!ossl_prov_is_running())
237
0
        return NULL;
238
239
0
    dst = kmac_new(src->provctx);
240
0
    if (dst == NULL)
241
0
        return NULL;
242
243
0
    if (!EVP_MD_CTX_copy(dst->ctx, src->ctx)
244
0
        || !ossl_prov_digest_copy(&dst->digest, &src->digest)) {
245
0
        kmac_free(dst);
246
0
        return NULL;
247
0
    }
248
#ifdef FIPS_MODULE
249
    dst->internal = src->internal;
250
#endif
251
0
    dst->out_len = src->out_len;
252
0
    dst->key_len = src->key_len;
253
0
    dst->custom_len = src->custom_len;
254
0
    dst->xof_mode = src->xof_mode;
255
0
    memcpy(dst->key, src->key, src->key_len);
256
0
    memcpy(dst->custom, src->custom, dst->custom_len);
257
0
    OSSL_FIPS_IND_COPY(dst, src)
258
259
0
    return dst;
260
0
}
261
262
static int kmac_setkey(struct kmac_data_st *kctx, const unsigned char *key,
263
                       size_t keylen)
264
0
{
265
0
    const EVP_MD *digest = ossl_prov_digest_md(&kctx->digest);
266
0
    int w = EVP_MD_get_block_size(digest);
267
268
0
    if (keylen < KMAC_MIN_KEY || keylen > KMAC_MAX_KEY) {
269
0
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
270
0
        return 0;
271
0
    }
272
#ifdef FIPS_MODULE
273
    /*
274
     * Only do the key check if KMAC is fetched directly.
275
     * Other algorithms that embed KMAC such as SSKDF will ignore this check.
276
     */
277
    if (!kctx->internal) {
278
        int approved = ossl_mac_check_key_size(keylen);
279
280
        if (!approved) {
281
            if (!OSSL_FIPS_IND_ON_UNAPPROVED(kctx, OSSL_FIPS_IND_SETTABLE1,
282
                                             PROV_LIBCTX_OF(kctx->provctx),
283
                                             "KMAC", "Key size",
284
                                             ossl_fips_config_kmac_key_check)) {
285
                ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
286
                return 0;
287
            }
288
        }
289
    }
290
#endif
291
0
    if (w <= 0) {
292
0
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DIGEST_LENGTH);
293
0
        return 0;
294
0
    }
295
0
    if (!kmac_bytepad_encode_key(kctx->key, sizeof(kctx->key), &kctx->key_len,
296
0
                                 key, keylen, (size_t)w))
297
0
        return 0;
298
0
    return 1;
299
0
}
300
301
/*
302
 * The init() assumes that any ctrl methods are set beforehand for
303
 * md, key and custom. Setting the fields afterwards will have no
304
 * effect on the output mac.
305
 */
306
static int kmac_init(void *vmacctx, const unsigned char *key,
307
                     size_t keylen, const OSSL_PARAM params[])
308
0
{
309
0
    struct kmac_data_st *kctx = vmacctx;
310
0
    EVP_MD_CTX *ctx = kctx->ctx;
311
0
    unsigned char *out;
312
0
    size_t out_len, block_len;
313
0
    int res, t;
314
315
0
    if (!ossl_prov_is_running() || !kmac_set_ctx_params(kctx, params))
316
0
        return 0;
317
318
0
    if (key != NULL) {
319
0
        if (!kmac_setkey(kctx, key, keylen))
320
0
            return 0;
321
0
    } else if (kctx->key_len == 0) {
322
        /* Check key has been set */
323
0
        ERR_raise(ERR_LIB_PROV, PROV_R_NO_KEY_SET);
324
0
        return 0;
325
0
    }
326
0
    if (!EVP_DigestInit_ex(kctx->ctx, ossl_prov_digest_md(&kctx->digest),
327
0
                           NULL))
328
0
        return 0;
329
330
0
    t = EVP_MD_get_block_size(ossl_prov_digest_md(&kctx->digest));
331
0
    if (t <= 0) {
332
0
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DIGEST_LENGTH);
333
0
        return 0;
334
0
    }
335
0
    block_len = t;
336
337
    /* Set default custom string if it is not already set */
338
0
    if (kctx->custom_len == 0) {
339
0
        const OSSL_PARAM cparams[] = {
340
0
            OSSL_PARAM_octet_string(OSSL_MAC_PARAM_CUSTOM, "", 0),
341
0
            OSSL_PARAM_END
342
0
        };
343
0
        (void)kmac_set_ctx_params(kctx, cparams);
344
0
    }
345
346
0
    if (!bytepad(NULL, &out_len, kmac_string, sizeof(kmac_string),
347
0
                 kctx->custom, kctx->custom_len, block_len)) {
348
0
        ERR_raise(ERR_LIB_PROV, ERR_R_INTERNAL_ERROR);
349
0
        return 0;
350
0
    }
351
0
    out = OPENSSL_malloc(out_len);
352
0
    if (out == NULL)
353
0
        return 0;
354
0
    res = bytepad(out, NULL, kmac_string, sizeof(kmac_string),
355
0
                  kctx->custom, kctx->custom_len, block_len)
356
0
          && EVP_DigestUpdate(ctx, out, out_len)
357
0
          && EVP_DigestUpdate(ctx, kctx->key, kctx->key_len);
358
0
    OPENSSL_free(out);
359
0
    return res;
360
0
}
361
362
static int kmac_update(void *vmacctx, const unsigned char *data,
363
                       size_t datalen)
364
0
{
365
0
    struct kmac_data_st *kctx = vmacctx;
366
367
0
    return EVP_DigestUpdate(kctx->ctx, data, datalen);
368
0
}
369
370
static int kmac_final(void *vmacctx, unsigned char *out, size_t *outl,
371
                      size_t outsize)
372
0
{
373
0
    struct kmac_data_st *kctx = vmacctx;
374
0
    EVP_MD_CTX *ctx = kctx->ctx;
375
0
    size_t lbits, len;
376
0
    unsigned char encoded_outlen[KMAC_MAX_ENCODED_HEADER_LEN];
377
0
    int ok;
378
379
0
    if (!ossl_prov_is_running())
380
0
        return 0;
381
382
    /* KMAC XOF mode sets the encoded length to 0 */
383
0
    lbits = (kctx->xof_mode ? 0 : (kctx->out_len * 8));
384
385
0
    ok = right_encode(encoded_outlen, sizeof(encoded_outlen), &len, lbits)
386
0
        && EVP_DigestUpdate(ctx, encoded_outlen, len)
387
0
        && EVP_DigestFinalXOF(ctx, out, kctx->out_len);
388
0
    *outl = kctx->out_len;
389
0
    return ok;
390
0
}
391
392
static const OSSL_PARAM known_gettable_ctx_params[] = {
393
    OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
394
    OSSL_PARAM_size_t(OSSL_MAC_PARAM_BLOCK_SIZE, NULL),
395
    OSSL_FIPS_IND_GETTABLE_CTX_PARAM()
396
    OSSL_PARAM_END
397
};
398
static const OSSL_PARAM *kmac_gettable_ctx_params(ossl_unused void *ctx,
399
                                                  ossl_unused void *provctx)
400
0
{
401
0
    return known_gettable_ctx_params;
402
0
}
403
404
static int kmac_get_ctx_params(void *vmacctx, OSSL_PARAM params[])
405
0
{
406
0
    struct kmac_data_st *kctx = vmacctx;
407
0
    OSSL_PARAM *p;
408
0
    int sz;
409
410
0
    if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_SIZE)) != NULL
411
0
            && !OSSL_PARAM_set_size_t(p, kctx->out_len))
412
0
        return 0;
413
414
0
    if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_BLOCK_SIZE)) != NULL) {
415
0
        sz = EVP_MD_block_size(ossl_prov_digest_md(&kctx->digest));
416
0
        if (!OSSL_PARAM_set_int(p, sz))
417
0
            return 0;
418
0
    }
419
420
0
    if (!OSSL_FIPS_IND_GET_CTX_PARAM(kctx, params))
421
0
        return 0;
422
423
0
    return 1;
424
0
}
425
426
static const OSSL_PARAM known_settable_ctx_params[] = {
427
    OSSL_PARAM_int(OSSL_MAC_PARAM_XOF, NULL),
428
    OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
429
    OSSL_PARAM_octet_string(OSSL_MAC_PARAM_KEY, NULL, 0),
430
    OSSL_PARAM_octet_string(OSSL_MAC_PARAM_CUSTOM, NULL, 0),
431
    OSSL_FIPS_IND_SETTABLE_CTX_PARAM(OSSL_MAC_PARAM_FIPS_NO_SHORT_MAC)
432
    OSSL_FIPS_IND_SETTABLE_CTX_PARAM(OSSL_MAC_PARAM_FIPS_KEY_CHECK)
433
    OSSL_PARAM_END
434
};
435
static const OSSL_PARAM *kmac_settable_ctx_params(ossl_unused void *ctx,
436
                                                  ossl_unused void *provctx)
437
0
{
438
0
    return known_settable_ctx_params;
439
0
}
440
441
/*
442
 * The following params can be set any time before final():
443
 *     - "outlen" or "size":    The requested output length.
444
 *     - "xof":                 If set, this indicates that right_encoded(0)
445
 *                              is part of the digested data, otherwise it
446
 *                              uses right_encoded(requested output length).
447
 *
448
 * All other params should be set before init().
449
 */
450
static int kmac_set_ctx_params(void *vmacctx, const OSSL_PARAM *params)
451
0
{
452
0
    struct kmac_data_st *kctx = vmacctx;
453
0
    const OSSL_PARAM *p;
454
455
0
    if (ossl_param_is_empty(params))
456
0
        return 1;
457
458
0
    if (!OSSL_FIPS_IND_SET_CTX_PARAM(kctx, OSSL_FIPS_IND_SETTABLE0, params,
459
0
                                     OSSL_MAC_PARAM_FIPS_NO_SHORT_MAC))
460
0
        return 0;
461
0
    if (!OSSL_FIPS_IND_SET_CTX_PARAM(kctx, OSSL_FIPS_IND_SETTABLE1, params,
462
0
                                     OSSL_MAC_PARAM_FIPS_KEY_CHECK))
463
0
        return 0;
464
465
0
    if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_XOF)) != NULL
466
0
        && !OSSL_PARAM_get_int(p, &kctx->xof_mode))
467
0
        return 0;
468
0
    if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_SIZE)) != NULL) {
469
0
        size_t sz = 0;
470
471
0
        if (!OSSL_PARAM_get_size_t(p, &sz))
472
0
            return 0;
473
0
        if (sz > KMAC_MAX_OUTPUT_LEN) {
474
0
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_OUTPUT_LENGTH);
475
0
            return 0;
476
0
        }
477
#ifdef FIPS_MODULE
478
        /* SP 800-185 8.4.2 mandates a minimum of 32 bits of output */
479
        if (sz < 32 / 8) {
480
            if (!OSSL_FIPS_IND_ON_UNAPPROVED(kctx, OSSL_FIPS_IND_SETTABLE0,
481
                                             PROV_LIBCTX_OF(kctx->provctx),
482
                                             "KMAC", "length",
483
                                             ossl_fips_config_no_short_mac)) {
484
                ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_OUTPUT_LENGTH);
485
                return 0;
486
            }
487
        }
488
#endif
489
0
        kctx->out_len = sz;
490
0
    }
491
0
    if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_KEY)) != NULL
492
0
            && !kmac_setkey(kctx, p->data, p->data_size))
493
0
        return 0;
494
0
    if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_CUSTOM))
495
0
        != NULL) {
496
0
        if (p->data_size > KMAC_MAX_CUSTOM) {
497
0
            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_CUSTOM_LENGTH);
498
0
            return 0;
499
0
        }
500
0
        if (!encode_string(kctx->custom, sizeof(kctx->custom), &kctx->custom_len,
501
0
                           p->data, p->data_size))
502
0
            return 0;
503
0
    }
504
0
    return 1;
505
0
}
506
507
/* Encoding/Padding Methods. */
508
509
/* Returns the number of bytes required to store 'bits' into a byte array */
510
static unsigned int get_encode_size(size_t bits)
511
0
{
512
0
    unsigned int cnt = 0, sz = sizeof(size_t);
513
514
0
    while (bits && (cnt < sz)) {
515
0
        ++cnt;
516
0
        bits >>= 8;
517
0
    }
518
    /* If bits is zero 1 byte is required */
519
0
    if (cnt == 0)
520
0
        cnt = 1;
521
0
    return cnt;
522
0
}
523
524
/*
525
 * Convert an integer into bytes . The number of bytes is appended
526
 * to the end of the buffer. Returns an array of bytes 'out' of size
527
 * *out_len.
528
 *
529
 * e.g if bits = 32, out[2] = { 0x20, 0x01 }
530
 */
531
static int right_encode(unsigned char *out, size_t out_max_len, size_t *out_len,
532
                        size_t bits)
533
0
{
534
0
    unsigned int len = get_encode_size(bits);
535
0
    int i;
536
537
0
    if (len >= out_max_len) {
538
0
        ERR_raise(ERR_LIB_PROV, PROV_R_LENGTH_TOO_LARGE);
539
0
        return 0;
540
0
    }
541
542
    /* MSB's are at the start of the bytes array */
543
0
    for (i = len - 1; i >= 0; --i) {
544
0
        out[i] = (unsigned char)(bits & 0xFF);
545
0
        bits >>= 8;
546
0
    }
547
    /* Tack the length onto the end */
548
0
    out[len] = (unsigned char)len;
549
550
    /* The Returned length includes the tacked on byte */
551
0
    *out_len = len + 1;
552
0
    return 1;
553
0
}
554
555
/*
556
 * Encodes a string with a left encoded length added. Note that the
557
 * in_len is converted to bits (*8).
558
 *
559
 * e.g- in="KMAC" gives out[6] = { 0x01, 0x20, 0x4B, 0x4D, 0x41, 0x43 }
560
 *                                 len   bits    K     M     A     C
561
 */
562
static int encode_string(unsigned char *out, size_t out_max_len, size_t *out_len,
563
                         const unsigned char *in, size_t in_len)
564
0
{
565
0
    if (in == NULL) {
566
0
        *out_len = 0;
567
0
    } else {
568
0
        size_t i, bits, len, sz;
569
570
0
        bits = 8 * in_len;
571
0
        len = get_encode_size(bits);
572
0
        sz = 1 + len + in_len;
573
574
0
        if (sz > out_max_len) {
575
0
            ERR_raise(ERR_LIB_PROV, PROV_R_LENGTH_TOO_LARGE);
576
0
            return 0;
577
0
        }
578
579
0
        out[0] = (unsigned char)len;
580
0
        for (i = len; i > 0; --i) {
581
0
            out[i] = (bits & 0xFF);
582
0
            bits >>= 8;
583
0
        }
584
0
        memcpy(out + len + 1, in, in_len);
585
0
        *out_len = sz;
586
0
    }
587
0
    return 1;
588
0
}
589
590
/*
591
 * Returns a zero padded encoding of the inputs in1 and an optional
592
 * in2 (can be NULL). The padded output must be a multiple of the blocksize 'w'.
593
 * The value of w is in bytes (< 256).
594
 *
595
 * The returned output is:
596
 *    zero_padded(multiple of w, (left_encode(w) || in1 [|| in2])
597
 */
598
static int bytepad(unsigned char *out, size_t *out_len,
599
                   const unsigned char *in1, size_t in1_len,
600
                   const unsigned char *in2, size_t in2_len, size_t w)
601
0
{
602
0
    int len;
603
0
    unsigned char *p = out;
604
0
    int sz = w;
605
606
0
    if (out == NULL) {
607
0
        if (out_len == NULL) {
608
0
            ERR_raise(ERR_LIB_PROV, ERR_R_PASSED_NULL_PARAMETER);
609
0
            return 0;
610
0
        }
611
0
        sz = 2 + in1_len + (in2 != NULL ? in2_len : 0);
612
0
        *out_len = (sz + w - 1) / w * w;
613
0
        return 1;
614
0
    }
615
616
0
    if (!ossl_assert(w <= 255))
617
0
        return 0;
618
619
    /* Left encoded w */
620
0
    *p++ = 1;
621
0
    *p++ = (unsigned char)w;
622
    /* || in1 */
623
0
    memcpy(p, in1, in1_len);
624
0
    p += in1_len;
625
    /* [ || in2 ] */
626
0
    if (in2 != NULL && in2_len > 0) {
627
0
        memcpy(p, in2, in2_len);
628
0
        p += in2_len;
629
0
    }
630
    /* Figure out the pad size (divisible by w) */
631
0
    len = p - out;
632
0
    sz = (len + w - 1) / w * w;
633
    /* zero pad the end of the buffer */
634
0
    if (sz != len)
635
0
        memset(p, 0, sz - len);
636
0
    if (out_len != NULL)
637
0
        *out_len = sz;
638
0
    return 1;
639
0
}
640
641
/* Returns out = bytepad(encode_string(in), w) */
642
static int kmac_bytepad_encode_key(unsigned char *out, size_t out_max_len,
643
                                   size_t *out_len,
644
                                   const unsigned char *in, size_t in_len,
645
                                   size_t w)
646
0
{
647
0
    unsigned char tmp[KMAC_MAX_KEY + KMAC_MAX_ENCODED_HEADER_LEN];
648
0
    size_t tmp_len;
649
650
0
    if (!encode_string(tmp, sizeof(tmp), &tmp_len, in, in_len))
651
0
        return 0;
652
0
    if (!bytepad(NULL, out_len, tmp, tmp_len, NULL, 0, w))
653
0
        return 0;
654
0
    if (!ossl_assert(*out_len <= out_max_len))
655
0
        return 0;
656
0
    return bytepad(out, NULL, tmp, tmp_len, NULL, 0, w);
657
0
}
658
659
#define IMPLEMENT_KMAC_TABLE(size, funcname, newname)                          \
660
const OSSL_DISPATCH ossl_kmac##size##_##funcname[] =                           \
661
{                                                                              \
662
    { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))kmac##size##_##newname },          \
663
    { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))kmac_dup },                        \
664
    { OSSL_FUNC_MAC_FREECTX, (void (*)(void))kmac_free },                      \
665
    { OSSL_FUNC_MAC_INIT, (void (*)(void))kmac_init },                         \
666
    { OSSL_FUNC_MAC_UPDATE, (void (*)(void))kmac_update },                     \
667
    { OSSL_FUNC_MAC_FINAL, (void (*)(void))kmac_final },                       \
668
    { OSSL_FUNC_MAC_GETTABLE_CTX_PARAMS,                                       \
669
      (void (*)(void))kmac_gettable_ctx_params },                              \
670
    { OSSL_FUNC_MAC_GET_CTX_PARAMS, (void (*)(void))kmac_get_ctx_params },     \
671
    { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS,                                       \
672
      (void (*)(void))kmac_settable_ctx_params },                              \
673
    { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))kmac_set_ctx_params },     \
674
    OSSL_DISPATCH_END                                                          \
675
}
676
677
#define KMAC_TABLE(size) IMPLEMENT_KMAC_TABLE(size, functions, new)
678
679
KMAC_TABLE(128);
680
KMAC_TABLE(256);
681
682
#ifdef FIPS_MODULE
683
# define KMAC_INTERNAL_TABLE(size)                                             \
684
static OSSL_FUNC_mac_newctx_fn kmac##size##_internal_new;                      \
685
static void *kmac##size##_internal_new(void *provctx)                          \
686
{                                                                              \
687
    struct kmac_data_st *macctx = kmac##size##_new(provctx);                   \
688
                                                                               \
689
    if (macctx != NULL)                                                        \
690
        macctx->internal = 1;                                                  \
691
    return macctx;                                                             \
692
}                                                                              \
693
IMPLEMENT_KMAC_TABLE(size, internal_functions, internal_new)
694
695
KMAC_INTERNAL_TABLE(128);
696
KMAC_INTERNAL_TABLE(256);
697
#endif /* FIPS_MODULE */