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