typedef struct private_prf_plus_t private_prf_plus_t;
+typedef bool (*apply_prf_t)(private_prf_plus_t *this);
+
/**
* Private data of an prf_plus_t object.
*
chunk_t seed;
/**
- * Octet which will be appended to the seed, 0 if not used
+ * Octet which will be appended to the seed if a counter is used.
*/
uint8_t counter;
* Buffer to store current PRF result.
*/
chunk_t buffer;
+
+ /**
+ * The prf application method depending on whether a counter is used.
+ */
+ apply_prf_t apply_prf;
};
+/**
+ * Apply the PRF using the running counter
+ */
+static bool apply_prf_counter(private_prf_plus_t *this)
+{
+ if (!this->prf->get_bytes(this->prf, this->seed, NULL) ||
+ !this->prf->get_bytes(this->prf, chunk_from_thing(this->counter),
+ this->buffer.ptr))
+ {
+ return FALSE;
+ }
+ this->counter++;
+ if (!this->counter)
+ { /* according to RFC 7296, section 2.13, prf+ is undefined once the
+ * counter wrapped, so let's fail for future calls */
+ this->apply_prf = (void*)return_false;
+ }
+ return TRUE;
+}
+
+/**
+ * Apply the PRF using the running counter
+ */
+static bool apply_prf(private_prf_plus_t *this)
+{
+ return this->prf->get_bytes(this->prf, this->seed, this->buffer.ptr);
+}
+
METHOD(prf_plus_t, get_bytes, bool,
private_prf_plus_t *this, size_t length, uint8_t *buffer)
{
{
return FALSE;
}
- if (this->counter)
- {
- if (!this->prf->get_bytes(this->prf, this->seed, NULL) ||
- !this->prf->get_bytes(this->prf,
- chunk_from_thing(this->counter), this->buffer.ptr))
- {
- return FALSE;
- }
- this->counter++;
- }
- else
+ if (!this->apply_prf(this))
{
- if (!this->prf->get_bytes(this->prf, this->seed,
- this->buffer.ptr))
- {
- return FALSE;
- }
+ return FALSE;
}
this->used = 0;
}
.prf = prf,
.seed = chunk_clone(seed),
.buffer = chunk_alloc(prf->get_block_size(prf)),
+ .apply_prf = counter ? apply_prf_counter : apply_prf,
+ .counter = 0x01,
);
- if (counter)
- {
- this->counter = 0x01;
- if (!this->prf->get_bytes(this->prf, this->seed, NULL) ||
- !this->prf->get_bytes(this->prf, chunk_from_thing(this->counter),
- this->buffer.ptr))
- {
- destroy(this);
- return NULL;
- }
- this->counter++;
- }
- else
+ if (!this->apply_prf(this))
{
- if (!this->prf->get_bytes(this->prf, this->seed, this->buffer.ptr))
- {
- destroy(this);
- return NULL;
- }
+ destroy(this);
+ return NULL;
}
-
return &this->public;
}
--- /dev/null
+/*
+ * Copyright (C) 2019 Tobias Brunner
+ * HSR Hochschule fuer Technik Rapperswil
+ *
+ * This program 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 2 of the License, or (at your
+ * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program 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.
+ */
+
+#include "test_suite.h"
+
+#include <crypto/prf_plus.h>
+
+static struct {
+ chunk_t key;
+ chunk_t seed;
+ chunk_t iterations[10];
+} counter_data[] = {
+ { .key = chunk_from_chars(0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,
+ 0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,
+ 0x0b,0x0b,0x0b,0x0b),
+ .seed = chunk_from_chars(0x48,0x69,0x20,0x54,0x68,0x65,0x72,0x65),
+ .iterations = {
+ chunk_from_chars(0xb9,0xbd,0xc0),
+ chunk_from_chars(0x89,0x88,0xb4,0xc2,0xb7,0x5a),
+ chunk_from_chars(0xa9,0x3e,0x59,0x6a,0xc8,0x42,0x05),
+ chunk_from_chars(0xfa,0x2d,0xdd,0xe1,0xbf,0x7a,0x25,0x72,
+ 0x06,0x7b,0x00,0xe1,0x4b,0x23,0x77,0x32),
+ chunk_from_chars(0x83,0x05,0x09,0x98,0x1a,0xd2,0xf9,0x4a),
+ chunk_from_chars(0x8c,0x32,0xa4,0x7d,0xaa,0x22,0x55,0xb6),
+ chunk_from_chars(0x60,0xc4,0x36,0x34,0x7a,0xe7,0x56,0xa6,
+ 0xed,0xc0,0x23,0x47,0x7d,0x80),
+ chunk_from_chars(0x95,0x90,0xe6,0x82,0xf6,0x1d,0x9c,0x04,
+ 0xb0,0x6b,0x4a,0xd9,0x71,0xa3,0x4c,0x81,
+ 0x47,0xfa,0x66,0x79),
+ chunk_from_chars(0x2f,0xf1,0x43,0x4b,0x93,0xc7,0x22,0xb3,
+ 0x2e,0x12,0xf4,0x88,0x32,0xeb,0xc1,0x5c,
+ 0xe2,0x36,0x9c,0xe7,0x1f,0xe9,0xb7,0xb8,
+ 0x1e,0x57,0x04,0xc1,0x4d,0x0f,0x52,0x80,
+ 0xa6,0xec,0x62,0x6e,0x99,0x2d,0x7a,0x9f),
+ },
+ },
+};
+
+START_TEST(test_vectors_counter)
+{
+ prf_plus_t *prf_plus;
+ prf_t *prf;
+ chunk_t *iter = counter_data[_i].iterations, out;
+
+ prf = lib->crypto->create_prf(lib->crypto, PRF_HMAC_SHA2_256);
+ ck_assert(prf->set_key(prf, counter_data[_i].key));
+ prf_plus = prf_plus_create(prf, TRUE, counter_data[_i].seed);
+ while (iter->ptr)
+ {
+ ck_assert(prf_plus->allocate_bytes(prf_plus, iter->len, &out));
+ ck_assert_chunk_eq(*iter, out);
+ chunk_free(&out);
+ iter++;
+ }
+ prf_plus->destroy(prf_plus);
+ prf->destroy(prf);
+}
+END_TEST
+
+START_TEST(test_wrap)
+{
+ prf_plus_t *prf_plus;
+ prf_t *prf;
+ u_char buf[32];
+ int i;
+
+ prf = lib->crypto->create_prf(lib->crypto, PRF_HMAC_SHA2_256);
+ ck_assert(prf->set_key(prf, counter_data[0].key));
+ prf_plus = prf_plus_create(prf, TRUE, counter_data[0].seed);
+ for (i = 1; i < 256; i++)
+ {
+ ck_assert(prf_plus->get_bytes(prf_plus, sizeof(buf), buf));
+ }
+ ck_assert(!prf_plus->get_bytes(prf_plus, sizeof(buf), buf));
+ prf_plus->destroy(prf_plus);
+ prf->destroy(prf);
+}
+END_TEST
+
+static struct {
+ chunk_t key;
+ chunk_t seed;
+ chunk_t iterations[10];
+} classic_data[] = {
+ { .key = chunk_from_chars(0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,
+ 0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,0x0b,
+ 0x0b,0x0b,0x0b,0x0b),
+ .seed = chunk_from_chars(0x48,0x69,0x20,0x54,0x68,0x65,0x72,0x65),
+ .iterations = {
+ chunk_from_chars(0xb0,0x34,0x4c),
+ chunk_from_chars(0x61,0xd8,0xdb,0x38,0x53,0x5c),
+ chunk_from_chars(0xa8,0xaf,0xce,0xaf,0x0b,0xf1,0x2b),
+ chunk_from_chars(0x88,0x1d,0xc2,0x00,0xc9,0x83,0x3d,0xa7,
+ 0x26,0xe9,0x37,0x6c,0x2e,0x32,0xcf,0xf7),
+ chunk_from_chars(0xd0,0x9a,0xe2,0x4b,0x3a,0x83,0xff,0xd4),
+ chunk_from_chars(0xb1,0xef,0xa5,0x94,0x5c,0xc5,0xed,0x85),
+ chunk_from_chars(0xb0,0xb2,0xcc,0x56,0xfc,0xf7,0x5d,0x23,
+ 0xa0,0xa3,0x4c,0xa4,0xdb,0xff,),
+ chunk_from_chars(0xea,0xfd,0xaa,0x6a,0x3b,0xf4,0x11,0x34,
+ 0x24,0xe4,0x50,0x2d,0xf9,0x7a,0x76,0x93,
+ 0x24,0xf6,0x11,0x24),
+ chunk_from_chars(0x24,0x3b,0x99,0x6e,0x7d,0x0f,0x35,0x99,
+ 0x88,0x79,0x73,0x6b,0xdb,0x70,0x65,0x9a,
+ 0x6e,0xfa,0xd2,0x39,0x94,0x10,0xe6,0xce,
+ 0x80,0x45,0x6e,0xb6,0x07,0x07,0x8f,0xe1,
+ 0xc4,0x7c,0x6b,0x5e,0x81,0x65,0x47,0x8a),
+ },
+ },
+};
+
+START_TEST(test_vectors_classic)
+{
+ prf_plus_t *prf_plus;
+ prf_t *prf;
+ chunk_t *iter = classic_data[_i].iterations, out;
+
+ prf = lib->crypto->create_prf(lib->crypto, PRF_HMAC_SHA2_256);
+ ck_assert(prf->set_key(prf, classic_data[_i].key));
+ prf_plus = prf_plus_create(prf, FALSE, classic_data[_i].seed);
+ while (iter->ptr)
+ {
+ ck_assert(prf_plus->allocate_bytes(prf_plus, iter->len, &out));
+ ck_assert_chunk_eq(*iter, out);
+ chunk_free(&out);
+ iter++;
+ }
+ prf_plus->destroy(prf_plus);
+ prf->destroy(prf);
+}
+END_TEST
+
+Suite *prf_plus_suite_create()
+{
+ Suite *s;
+ TCase *tc;
+
+ s = suite_create("prf_plus");
+
+ tc = tcase_create("counter");
+ tcase_add_loop_test(tc, test_vectors_counter, 0, countof(counter_data));
+ tcase_add_test(tc, test_wrap);
+ suite_add_tcase(s, tc);
+
+ tc = tcase_create("no counter");
+ tcase_add_loop_test(tc, test_vectors_classic, 0, countof(classic_data));
+ suite_add_tcase(s, tc);
+
+ return s;
+}