1 /** Code to exercise a PSA key object, i.e. validate that it seems well-formed
2  * and can do what it is supposed to do.
3  */
4 /*
5  *  Copyright The Mbed TLS Contributors
6  *  SPDX-License-Identifier: Apache-2.0
7  *
8  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
9  *  not use this file except in compliance with the License.
10  *  You may obtain a copy of the License at
11  *
12  *  http://www.apache.org/licenses/LICENSE-2.0
13  *
14  *  Unless required by applicable law or agreed to in writing, software
15  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
16  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17  *  See the License for the specific language governing permissions and
18  *  limitations under the License.
19  */
20 
21 #ifndef PSA_EXERCISE_KEY_H
22 #define PSA_EXERCISE_KEY_H
23 
24 #include "test/helpers.h"
25 #include "test/psa_crypto_helpers.h"
26 
27 #include <psa/crypto.h>
28 
29 /** \def KNOWN_SUPPORTED_HASH_ALG
30  *
31  * A hash algorithm that is known to be supported.
32  *
33  * This is used in some smoke tests.
34  */
35 #if defined(PSA_WANT_ALG_MD5)
36 #define KNOWN_SUPPORTED_HASH_ALG PSA_ALG_MD5
37 /* MBEDTLS_RIPEMD160_C omitted. This is necessary for the sake of
38  * exercise_signature_key() because Mbed TLS doesn't support RIPEMD160
39  * in RSA PKCS#1v1.5 signatures. A RIPEMD160-only configuration would be
40  * implausible anyway. */
41 #elif defined(PSA_WANT_ALG_SHA_1)
42 #define KNOWN_SUPPORTED_HASH_ALG PSA_ALG_SHA_1
43 #elif defined(PSA_WANT_ALG_SHA_256)
44 #define KNOWN_SUPPORTED_HASH_ALG PSA_ALG_SHA_256
45 #elif defined(PSA_WANT_ALG_SHA_384)
46 #define KNOWN_SUPPORTED_HASH_ALG PSA_ALG_SHA_384
47 #elif defined(PSA_WANT_ALG_SHA_512)
48 #define KNOWN_SUPPORTED_HASH_ALG PSA_ALG_SHA_512
49 #elif defined(PSA_WANT_ALG_SHA3_256)
50 #define KNOWN_SUPPORTED_HASH_ALG PSA_ALG_SHA3_256
51 #else
52 #undef KNOWN_SUPPORTED_HASH_ALG
53 #endif
54 
55 /** \def KNOWN_SUPPORTED_BLOCK_CIPHER
56  *
57  * A block cipher that is known to be supported.
58  *
59  * For simplicity's sake, stick to block ciphers with 16-byte blocks.
60  */
61 #if defined(MBEDTLS_AES_C)
62 #define KNOWN_SUPPORTED_BLOCK_CIPHER PSA_KEY_TYPE_AES
63 #elif defined(MBEDTLS_ARIA_C)
64 #define KNOWN_SUPPORTED_BLOCK_CIPHER PSA_KEY_TYPE_ARIA
65 #elif defined(MBEDTLS_CAMELLIA_C)
66 #define KNOWN_SUPPORTED_BLOCK_CIPHER PSA_KEY_TYPE_CAMELLIA
67 #undef KNOWN_SUPPORTED_BLOCK_CIPHER
68 #endif
69 
70 /** \def KNOWN_SUPPORTED_MAC_ALG
71  *
72  * A MAC mode that is known to be supported.
73  *
74  * It must either be HMAC with #KNOWN_SUPPORTED_HASH_ALG or
75  * a block cipher-based MAC with #KNOWN_SUPPORTED_BLOCK_CIPHER.
76  *
77  * This is used in some smoke tests.
78  */
79 #if defined(KNOWN_SUPPORTED_HASH_ALG) && defined(PSA_WANT_ALG_HMAC)
80 #define KNOWN_SUPPORTED_MAC_ALG ( PSA_ALG_HMAC( KNOWN_SUPPORTED_HASH_ALG ) )
81 #define KNOWN_SUPPORTED_MAC_KEY_TYPE PSA_KEY_TYPE_HMAC
82 #elif defined(KNOWN_SUPPORTED_BLOCK_CIPHER) && defined(MBEDTLS_CMAC_C)
83 #define KNOWN_SUPPORTED_MAC_ALG PSA_ALG_CMAC
84 #define KNOWN_SUPPORTED_MAC_KEY_TYPE KNOWN_SUPPORTED_BLOCK_CIPHER
85 #else
86 #undef KNOWN_SUPPORTED_MAC_ALG
87 #undef KNOWN_SUPPORTED_MAC_KEY_TYPE
88 #endif
89 
90 /** \def KNOWN_SUPPORTED_BLOCK_CIPHER_ALG
91  *
92  * A cipher algorithm and key type that are known to be supported.
93  *
94  * This is used in some smoke tests.
95  */
96 #if defined(KNOWN_SUPPORTED_BLOCK_CIPHER) && defined(MBEDTLS_CIPHER_MODE_CTR)
97 #define KNOWN_SUPPORTED_BLOCK_CIPHER_ALG PSA_ALG_CTR
98 #elif defined(KNOWN_SUPPORTED_BLOCK_CIPHER) && defined(MBEDTLS_CIPHER_MODE_CBC)
99 #define KNOWN_SUPPORTED_BLOCK_CIPHER_ALG PSA_ALG_CBC_NO_PADDING
100 #elif defined(KNOWN_SUPPORTED_BLOCK_CIPHER) && defined(MBEDTLS_CIPHER_MODE_CFB)
101 #define KNOWN_SUPPORTED_BLOCK_CIPHER_ALG PSA_ALG_CFB
102 #elif defined(KNOWN_SUPPORTED_BLOCK_CIPHER) && defined(MBEDTLS_CIPHER_MODE_OFB)
103 #define KNOWN_SUPPORTED_BLOCK_CIPHER_ALG PSA_ALG_OFB
104 #else
105 #undef KNOWN_SUPPORTED_BLOCK_CIPHER_ALG
106 #endif
107 #if defined(KNOWN_SUPPORTED_BLOCK_CIPHER_ALG)
108 #define KNOWN_SUPPORTED_CIPHER_ALG KNOWN_SUPPORTED_BLOCK_CIPHER_ALG
109 #define KNOWN_SUPPORTED_CIPHER_KEY_TYPE KNOWN_SUPPORTED_BLOCK_CIPHER
110 #else
111 #undef KNOWN_SUPPORTED_CIPHER_ALG
112 #undef KNOWN_SUPPORTED_CIPHER_KEY_TYPE
113 #endif
114 
115 /** Convenience function to set up a key derivation.
116  *
117  * In case of failure, mark the current test case as failed.
118  *
119  * The inputs \p input1 and \p input2 are, in order:
120  * - HKDF: salt, info.
121  * - TKS 1.2 PRF, TLS 1.2 PSK-to-MS: seed, label.
122  *
123  * \param operation         The operation object to use.
124  *                          It must be in the initialized state.
125  * \param key               The key to use.
126  * \param alg               The algorithm to use.
127  * \param input1            The first input to pass.
128  * \param input1_length     The length of \p input1 in bytes.
129  * \param input2            The first input to pass.
130  * \param input2_length     The length of \p input2 in bytes.
131  * \param capacity          The capacity to set.
132  *
133  * \return                  \c 1 on success, \c 0 on failure.
134  */
135 int mbedtls_test_psa_setup_key_derivation_wrap(
136     psa_key_derivation_operation_t* operation,
137     mbedtls_svc_key_id_t key,
138     psa_algorithm_t alg,
139     const unsigned char* input1, size_t input1_length,
140     const unsigned char* input2, size_t input2_length,
141     size_t capacity );
142 
143 /** Perform a key agreement using the given key pair against its public key
144  * using psa_raw_key_agreement().
145  *
146  * The result is discarded. The purpose of this function is to smoke-test a key.
147  *
148  * In case of failure, mark the current test case as failed.
149  *
150  * \param alg               A key agreement algorithm compatible with \p key.
151  * \param key               A key that allows key agreement with \p alg.
152  *
153  * \return                  \c 1 on success, \c 0 on failure.
154  */
155 psa_status_t mbedtls_test_psa_raw_key_agreement_with_self(
156     psa_algorithm_t alg,
157     mbedtls_svc_key_id_t key );
158 
159 /** Perform a key agreement using the given key pair against its public key
160  * using psa_key_derivation_raw_key().
161  *
162  * The result is discarded. The purpose of this function is to smoke-test a key.
163  *
164  * In case of failure, mark the current test case as failed.
165  *
166  * \param operation         An operation that has been set up for a key
167  *                          agreement algorithm that is compatible with
168  *                          \p key.
169  * \param key               A key pair object that is suitable for a key
170  *                          agreement with \p operation.
171  *
172  * \return                  \c 1 on success, \c 0 on failure.
173  */
174 psa_status_t mbedtls_test_psa_key_agreement_with_self(
175     psa_key_derivation_operation_t *operation,
176     mbedtls_svc_key_id_t key );
177 
178 /** Perform sanity checks on the given key representation.
179  *
180  * If any of the checks fail, mark the current test case as failed.
181  *
182  * The checks depend on the key type.
183  * - All types: check the export size against maximum-size macros.
184  * - DES: parity bits.
185  * - RSA: check the ASN.1 structure and the size and parity of the integers.
186  * - ECC private or public key: exact representation length.
187  * - Montgomery public key: first byte.
188  *
189  * \param type              The key type.
190  * \param bits              The key size in bits.
191  * \param exported          A buffer containing the key representation.
192  * \param exported_length   The length of \p exported in bytes.
193  *
194  * \return                  \c 1 if all checks passed, \c 0 on failure.
195  */
196 int mbedtls_test_psa_exported_key_sanity_check(
197     psa_key_type_t type, size_t bits,
198     const uint8_t *exported, size_t exported_length );
199 
200 /** Do smoke tests on a key.
201  *
202  * Perform one of each operation indicated by \p alg (decrypt/encrypt,
203  * sign/verify, or derivation) that is permitted according to \p usage.
204  * \p usage and \p alg should correspond to the expected policy on the
205  * key.
206  *
207  * Export the key if permitted by \p usage, and check that the output
208  * looks sensible. If \p usage forbids export, check that
209  * \p psa_export_key correctly rejects the attempt. If the key is
210  * asymmetric, also check \p psa_export_public_key.
211  *
212  * If the key fails the tests, this function calls the test framework's
213  * `mbedtls_test_fail` function and returns false. Otherwise this function
214  * returns true. Therefore it should be used as follows:
215  * ```
216  * if( ! exercise_key( ... ) ) goto exit;
217  * ```
218  *
219  * \param key       The key to exercise. It should be capable of performing
220  *                  \p alg.
221  * \param usage     The usage flags to assume.
222  * \param alg       The algorithm to exercise.
223  *
224  * \retval 0 The key failed the smoke tests.
225  * \retval 1 The key passed the smoke tests.
226  */
227 int mbedtls_test_psa_exercise_key( mbedtls_svc_key_id_t key,
228                                    psa_key_usage_t usage,
229                                    psa_algorithm_t alg );
230 
231 psa_key_usage_t mbedtls_test_psa_usage_to_exercise( psa_key_type_t type,
232                                                     psa_algorithm_t alg );
233 
234 #endif /* PSA_EXERCISE_KEY_H */
235