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#include "common.h"
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "mbedtls/ctr_drbg.h"
#if defined(MBEDTLS_PLATFORM_TIME_ALT)
mbedtls_time_t dummy_constant_time(mbedtls_time_t *time)
{
(void) time;
return 0x5af2a056;
}
#endif
void dummy_init()
{
#if defined(MBEDTLS_PLATFORM_TIME_ALT)
mbedtls_platform_set_time(dummy_constant_time);
#else
fprintf(stderr, "Warning: fuzzing without constant time\n");
#endif
}
int dummy_send(void *ctx, const unsigned char *buf, size_t len)
{
//silence warning about unused parameter
(void) ctx;
(void) buf;
//pretends we wrote everything ok
if (len > INT_MAX) {
return -1;
}
return (int) len;
}
int fuzz_recv(void *ctx, unsigned char *buf, size_t len)
{
//reads from the buffer from fuzzer
fuzzBufferOffset_t *biomemfuzz = (fuzzBufferOffset_t *) ctx;
if (biomemfuzz->Offset == biomemfuzz->Size) {
//EOF
return 0;
}
if (len > INT_MAX) {
return -1;
}
if (len + biomemfuzz->Offset > biomemfuzz->Size) {
//do not overflow
len = biomemfuzz->Size - biomemfuzz->Offset;
}
memcpy(buf, biomemfuzz->Data + biomemfuzz->Offset, len);
biomemfuzz->Offset += len;
return (int) len;
}
int dummy_random(void *p_rng, unsigned char *output, size_t output_len)
{
int ret;
size_t i;
#if defined(MBEDTLS_CTR_DRBG_C)
//use mbedtls_ctr_drbg_random to find bugs in it
ret = mbedtls_ctr_drbg_random(p_rng, output, output_len);
#else
(void) p_rng;
ret = 0;
#endif
for (i = 0; i < output_len; i++) {
//replace result with pseudo random
output[i] = (unsigned char) rand();
}
return ret;
}
int dummy_entropy(void *data, unsigned char *output, size_t len)
{
size_t i;
(void) data;
//use mbedtls_entropy_func to find bugs in it
//test performance impact of entropy
//ret = mbedtls_entropy_func(data, output, len);
for (i = 0; i < len; i++) {
//replace result with pseudo random
output[i] = (unsigned char) rand();
}
return 0;
}
int fuzz_recv_timeout(void *ctx, unsigned char *buf, size_t len,
uint32_t timeout)
{
(void) timeout;
return fuzz_recv(ctx, buf, len);
}
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