1/* BEGIN_HEADER */
2#include "mbedtls/hmac_drbg.h"
3
4typedef struct
5{
6    unsigned char *p;
7    size_t len;
8} entropy_ctx;
9
10int mbedtls_entropy_func( void *data, unsigned char *buf, size_t len )
11{
12    entropy_ctx *ctx = (entropy_ctx *) data;
13
14    if( len > ctx->len )
15        return( -1 );
16
17    memcpy( buf, ctx->p, len );
18
19    ctx->p += len;
20    ctx->len -= len;
21
22    return( 0 );
23}
24/* END_HEADER */
25
26/* BEGIN_DEPENDENCIES
27 * depends_on:MBEDTLS_HMAC_DRBG_C
28 * END_DEPENDENCIES
29 */
30
31/* BEGIN_CASE */
32void hmac_drbg_entropy_usage( int md_alg )
33{
34    unsigned char out[16];
35    unsigned char buf[1024];
36    const mbedtls_md_info_t *md_info;
37    mbedtls_hmac_drbg_context ctx;
38    entropy_ctx entropy;
39    size_t last_len, i, reps = 10;
40
41    mbedtls_hmac_drbg_init( &ctx );
42    memset( buf, 0, sizeof( buf ) );
43    memset( out, 0, sizeof( out ) );
44
45    entropy.len = sizeof( buf );
46    entropy.p = buf;
47
48    md_info = mbedtls_md_info_from_type( md_alg );
49    TEST_ASSERT( md_info != NULL );
50
51    /* Init must use entropy */
52    last_len = entropy.len;
53    TEST_ASSERT( mbedtls_hmac_drbg_seed( &ctx, md_info, mbedtls_entropy_func, &entropy,
54                                 NULL, 0 ) == 0 );
55    TEST_ASSERT( entropy.len < last_len );
56
57    /* By default, PR is off and reseed_interval is large,
58     * so the next few calls should not use entropy */
59    last_len = entropy.len;
60    for( i = 0; i < reps; i++ )
61    {
62        TEST_ASSERT( mbedtls_hmac_drbg_random( &ctx, out, sizeof( out ) - 4 ) == 0 );
63        TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, out, sizeof( out ) - 4,
64                                                buf, 16 ) == 0 );
65    }
66    TEST_ASSERT( entropy.len == last_len );
67
68    /* While at it, make sure we didn't write past the requested length */
69    TEST_ASSERT( out[sizeof( out ) - 4] == 0 );
70    TEST_ASSERT( out[sizeof( out ) - 3] == 0 );
71    TEST_ASSERT( out[sizeof( out ) - 2] == 0 );
72    TEST_ASSERT( out[sizeof( out ) - 1] == 0 );
73
74    /* Set reseed_interval to the number of calls done,
75     * so the next call should reseed */
76    mbedtls_hmac_drbg_set_reseed_interval( &ctx, 2 * reps );
77    TEST_ASSERT( mbedtls_hmac_drbg_random( &ctx, out, sizeof( out ) ) == 0 );
78    TEST_ASSERT( entropy.len < last_len );
79
80    /* The new few calls should not reseed */
81    last_len = entropy.len;
82    for( i = 0; i < reps / 2; i++ )
83    {
84        TEST_ASSERT( mbedtls_hmac_drbg_random( &ctx, out, sizeof( out ) ) == 0 );
85        TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, out, sizeof( out ) ,
86                                                buf, 16 ) == 0 );
87    }
88    TEST_ASSERT( entropy.len == last_len );
89
90    /* Now enable PR, so the next few calls should all reseed */
91    mbedtls_hmac_drbg_set_prediction_resistance( &ctx, MBEDTLS_HMAC_DRBG_PR_ON );
92    TEST_ASSERT( mbedtls_hmac_drbg_random( &ctx, out, sizeof( out ) ) == 0 );
93    TEST_ASSERT( entropy.len < last_len );
94
95    /* Finally, check setting entropy_len */
96    mbedtls_hmac_drbg_set_entropy_len( &ctx, 42 );
97    last_len = entropy.len;
98    TEST_ASSERT( mbedtls_hmac_drbg_random( &ctx, out, sizeof( out ) ) == 0 );
99    TEST_ASSERT( (int) last_len - entropy.len == 42 );
100
101    mbedtls_hmac_drbg_set_entropy_len( &ctx, 13 );
102    last_len = entropy.len;
103    TEST_ASSERT( mbedtls_hmac_drbg_random( &ctx, out, sizeof( out ) ) == 0 );
104    TEST_ASSERT( (int) last_len - entropy.len == 13 );
105
106exit:
107    mbedtls_hmac_drbg_free( &ctx );
108}
109/* END_CASE */
110
111/* BEGIN_CASE depends_on:MBEDTLS_FS_IO */
112void hmac_drbg_seed_file( int md_alg, char *path, int ret )
113{
114    const mbedtls_md_info_t *md_info;
115    mbedtls_hmac_drbg_context ctx;
116
117    mbedtls_hmac_drbg_init( &ctx );
118
119    md_info = mbedtls_md_info_from_type( md_alg );
120    TEST_ASSERT( md_info != NULL );
121
122    TEST_ASSERT( mbedtls_hmac_drbg_seed( &ctx, md_info, rnd_std_rand, NULL,
123                                 NULL, 0 ) == 0 );
124
125    TEST_ASSERT( mbedtls_hmac_drbg_write_seed_file( &ctx, path ) == ret );
126    TEST_ASSERT( mbedtls_hmac_drbg_update_seed_file( &ctx, path ) == ret );
127
128exit:
129    mbedtls_hmac_drbg_free( &ctx );
130}
131/* END_CASE */
132
133/* BEGIN_CASE */
134void hmac_drbg_buf( int md_alg )
135{
136    unsigned char out[16];
137    unsigned char buf[100];
138    const mbedtls_md_info_t *md_info;
139    mbedtls_hmac_drbg_context ctx;
140    size_t i;
141
142    mbedtls_hmac_drbg_init( &ctx );
143    memset( buf, 0, sizeof( buf ) );
144    memset( out, 0, sizeof( out ) );
145
146    md_info = mbedtls_md_info_from_type( md_alg );
147    TEST_ASSERT( md_info != NULL );
148    TEST_ASSERT( mbedtls_hmac_drbg_seed_buf( &ctx, md_info, buf, sizeof( buf ) ) == 0 );
149
150    /* Make sure it never tries to reseed (would segfault otherwise) */
151    mbedtls_hmac_drbg_set_reseed_interval( &ctx, 3 );
152    mbedtls_hmac_drbg_set_prediction_resistance( &ctx, MBEDTLS_HMAC_DRBG_PR_ON );
153
154    for( i = 0; i < 30; i++ )
155        TEST_ASSERT( mbedtls_hmac_drbg_random( &ctx, out, sizeof( out ) ) == 0 );
156
157exit:
158    mbedtls_hmac_drbg_free( &ctx );
159}
160/* END_CASE */
161
162/* BEGIN_CASE */
163void hmac_drbg_no_reseed( int md_alg,
164                          char *entropy_hex, char *custom_hex,
165                          char *add1_hex, char *add2_hex,
166                          char *output_hex )
167{
168    unsigned char data[1024];
169    unsigned char entropy[512];
170    unsigned char custom[512];
171    unsigned char add1[512];
172    unsigned char add2[512];
173    unsigned char output[512];
174    unsigned char my_output[512];
175    size_t custom_len, add1_len, add2_len, out_len;
176    entropy_ctx p_entropy;
177    const mbedtls_md_info_t *md_info;
178    mbedtls_hmac_drbg_context ctx;
179
180    mbedtls_hmac_drbg_init( &ctx );
181    memset( my_output, 0, sizeof my_output );
182
183    custom_len = unhexify( custom, custom_hex );
184    add1_len = unhexify( add1, add1_hex );
185    add2_len = unhexify( add2, add2_hex );
186    out_len = unhexify( output, output_hex );
187    p_entropy.len = unhexify( entropy, entropy_hex );
188    p_entropy.p = entropy;
189
190    md_info = mbedtls_md_info_from_type( md_alg );
191    TEST_ASSERT( md_info != NULL );
192
193    /* Test the simplified buffer-based variant */
194    memcpy( data, entropy, p_entropy.len );
195    memcpy( data + p_entropy.len, custom, custom_len );
196    TEST_ASSERT( mbedtls_hmac_drbg_seed_buf( &ctx, md_info,
197                                     data, p_entropy.len + custom_len ) == 0 );
198    TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, my_output, out_len,
199                                            add1, add1_len ) == 0 );
200    TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, my_output, out_len,
201                                            add2, add2_len ) == 0 );
202
203    /* clear for second run */
204    mbedtls_hmac_drbg_free( &ctx );
205
206    TEST_ASSERT( memcmp( my_output, output, out_len ) == 0 );
207
208    /* And now the normal entropy-based variant */
209    TEST_ASSERT( mbedtls_hmac_drbg_seed( &ctx, md_info, mbedtls_entropy_func, &p_entropy,
210                                 custom, custom_len ) == 0 );
211    TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, my_output, out_len,
212                                            add1, add1_len ) == 0 );
213    TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, my_output, out_len,
214                                            add2, add2_len ) == 0 );
215    TEST_ASSERT( memcmp( my_output, output, out_len ) == 0 );
216
217exit:
218    mbedtls_hmac_drbg_free( &ctx );
219}
220/* END_CASE */
221
222/* BEGIN_CASE */
223void hmac_drbg_nopr( int md_alg,
224                     char *entropy_hex, char *custom_hex,
225                     char *add1_hex, char *add2_hex, char *add3_hex,
226                     char *output_hex )
227{
228    unsigned char entropy[512];
229    unsigned char custom[512];
230    unsigned char add1[512];
231    unsigned char add2[512];
232    unsigned char add3[512];
233    unsigned char output[512];
234    unsigned char my_output[512];
235    size_t custom_len, add1_len, add2_len, add3_len, out_len;
236    entropy_ctx p_entropy;
237    const mbedtls_md_info_t *md_info;
238    mbedtls_hmac_drbg_context ctx;
239
240    mbedtls_hmac_drbg_init( &ctx );
241    memset( my_output, 0, sizeof my_output );
242
243    custom_len = unhexify( custom, custom_hex );
244    add1_len = unhexify( add1, add1_hex );
245    add2_len = unhexify( add2, add2_hex );
246    add3_len = unhexify( add3, add3_hex );
247    out_len = unhexify( output, output_hex );
248    p_entropy.len = unhexify( entropy, entropy_hex );
249    p_entropy.p = entropy;
250
251    md_info = mbedtls_md_info_from_type( md_alg );
252    TEST_ASSERT( md_info != NULL );
253
254    TEST_ASSERT( mbedtls_hmac_drbg_seed( &ctx, md_info, mbedtls_entropy_func, &p_entropy,
255                                 custom, custom_len ) == 0 );
256    TEST_ASSERT( mbedtls_hmac_drbg_reseed( &ctx, add1, add1_len ) == 0 );
257    TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, my_output, out_len,
258                                            add2, add2_len ) == 0 );
259    TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, my_output, out_len,
260                                            add3, add3_len ) == 0 );
261
262    TEST_ASSERT( memcmp( my_output, output, out_len ) == 0 );
263
264exit:
265    mbedtls_hmac_drbg_free( &ctx );
266}
267/* END_CASE */
268
269/* BEGIN_CASE */
270void hmac_drbg_pr( int md_alg,
271                   char *entropy_hex, char *custom_hex,
272                   char *add1_hex, char *add2_hex,
273                   char *output_hex )
274{
275    unsigned char entropy[512];
276    unsigned char custom[512];
277    unsigned char add1[512];
278    unsigned char add2[512];
279    unsigned char output[512];
280    unsigned char my_output[512];
281    size_t custom_len, add1_len, add2_len, out_len;
282    entropy_ctx p_entropy;
283    const mbedtls_md_info_t *md_info;
284    mbedtls_hmac_drbg_context ctx;
285
286    mbedtls_hmac_drbg_init( &ctx );
287    memset( my_output, 0, sizeof my_output );
288
289    custom_len = unhexify( custom, custom_hex );
290    add1_len = unhexify( add1, add1_hex );
291    add2_len = unhexify( add2, add2_hex );
292    out_len = unhexify( output, output_hex );
293    p_entropy.len = unhexify( entropy, entropy_hex );
294    p_entropy.p = entropy;
295
296    md_info = mbedtls_md_info_from_type( md_alg );
297    TEST_ASSERT( md_info != NULL );
298
299    TEST_ASSERT( mbedtls_hmac_drbg_seed( &ctx, md_info, mbedtls_entropy_func, &p_entropy,
300                                 custom, custom_len ) == 0 );
301    mbedtls_hmac_drbg_set_prediction_resistance( &ctx, MBEDTLS_HMAC_DRBG_PR_ON );
302    TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, my_output, out_len,
303                                            add1, add1_len ) == 0 );
304    TEST_ASSERT( mbedtls_hmac_drbg_random_with_add( &ctx, my_output, out_len,
305                                            add2, add2_len ) == 0 );
306
307    TEST_ASSERT( memcmp( my_output, output, out_len ) == 0 );
308
309exit:
310    mbedtls_hmac_drbg_free( &ctx );
311}
312/* END_CASE */
313
314/* BEGIN_CASE depends_on:MBEDTLS_SELF_TEST */
315void hmac_drbg_selftest( )
316{
317    TEST_ASSERT( mbedtls_hmac_drbg_self_test( 1 ) == 0 );
318}
319/* END_CASE */
320