1 #include "common.h"
2 #include <limits.h>
3 #include <stdio.h>
4 #include <string.h>
5 #include <stdlib.h>
6 #include "mbedtls/ctr_drbg.h"
7
8 #if defined(MBEDTLS_PLATFORM_TIME_ALT)
dummy_constant_time(mbedtls_time_t * time)9 mbedtls_time_t dummy_constant_time( mbedtls_time_t* time )
10 {
11 (void) time;
12 return 0x5af2a056;
13 }
14 #endif
15
dummy_init()16 void dummy_init()
17 {
18 #if defined(MBEDTLS_PLATFORM_TIME_ALT)
19 mbedtls_platform_set_time( dummy_constant_time );
20 #else
21 fprintf(stderr, "Warning: fuzzing without constant time\n");
22 #endif
23 }
24
dummy_send(void * ctx,const unsigned char * buf,size_t len)25 int dummy_send( void *ctx, const unsigned char *buf, size_t len )
26 {
27 //silence warning about unused parameter
28 (void) ctx;
29 (void) buf;
30
31 //pretends we wrote everything ok
32 if( len > INT_MAX ) {
33 return( -1 );
34 }
35 return( (int) len );
36 }
37
fuzz_recv(void * ctx,unsigned char * buf,size_t len)38 int fuzz_recv( void *ctx, unsigned char *buf, size_t len )
39 {
40 //reads from the buffer from fuzzer
41 fuzzBufferOffset_t * biomemfuzz = (fuzzBufferOffset_t *) ctx;
42
43 if(biomemfuzz->Offset == biomemfuzz->Size) {
44 //EOF
45 return( 0 );
46 }
47 if( len > INT_MAX ) {
48 return( -1 );
49 }
50 if( len + biomemfuzz->Offset > biomemfuzz->Size ) {
51 //do not overflow
52 len = biomemfuzz->Size - biomemfuzz->Offset;
53 }
54 memcpy(buf, biomemfuzz->Data + biomemfuzz->Offset, len);
55 biomemfuzz->Offset += len;
56 return( (int) len );
57 }
58
dummy_random(void * p_rng,unsigned char * output,size_t output_len)59 int dummy_random( void *p_rng, unsigned char *output, size_t output_len )
60 {
61 int ret;
62 size_t i;
63
64 #if defined(MBEDTLS_CTR_DRBG_C)
65 //mbedtls_ctr_drbg_random requires a valid mbedtls_ctr_drbg_context in p_rng
66 if( p_rng != NULL ) {
67 //use mbedtls_ctr_drbg_random to find bugs in it
68 ret = mbedtls_ctr_drbg_random(p_rng, output, output_len);
69 } else {
70 //fall through to pseudo-random
71 ret = 0;
72 }
73 #else
74 (void) p_rng;
75 ret = 0;
76 #endif
77 for (i=0; i<output_len; i++) {
78 //replace result with pseudo random
79 output[i] = (unsigned char) rand();
80 }
81 return( ret );
82 }
83
dummy_entropy(void * data,unsigned char * output,size_t len)84 int dummy_entropy( void *data, unsigned char *output, size_t len )
85 {
86 size_t i;
87 (void) data;
88
89 //use mbedtls_entropy_func to find bugs in it
90 //test performance impact of entropy
91 //ret = mbedtls_entropy_func(data, output, len);
92 for (i=0; i<len; i++) {
93 //replace result with pseudo random
94 output[i] = (unsigned char) rand();
95 }
96 return( 0 );
97 }
98
fuzz_recv_timeout(void * ctx,unsigned char * buf,size_t len,uint32_t timeout)99 int fuzz_recv_timeout( void *ctx, unsigned char *buf, size_t len,
100 uint32_t timeout )
101 {
102 (void) timeout;
103
104 return fuzz_recv(ctx, buf, len);
105 }
106