Coverage Report

Created: 2025-03-01 06:26

/src/mbedtls/programs/fuzz/common.c
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Source (jump to first uncovered line)
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#include "common.h"
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#include <limits.h>
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include "mbedtls/ctr_drbg.h"
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#if defined(MBEDTLS_PLATFORM_TIME_ALT)
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mbedtls_time_t dummy_constant_time(mbedtls_time_t *time)
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13.8k
{
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13.8k
    (void) time;
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13.8k
    return 0x5af2a056;
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13.8k
}
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#endif
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void dummy_init(void)
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{
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#if defined(MBEDTLS_PLATFORM_TIME_ALT)
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6
    mbedtls_platform_set_time(dummy_constant_time);
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#else
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    fprintf(stderr, "Warning: fuzzing without constant time\n");
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#endif
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}
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int dummy_send(void *ctx, const unsigned char *buf, size_t len)
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25.7k
{
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    //silence warning about unused parameter
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25.7k
    (void) ctx;
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25.7k
    (void) buf;
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    //pretends we wrote everything ok
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25.7k
    if (len > INT_MAX) {
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0
        return -1;
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0
    }
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25.7k
    return (int) len;
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25.7k
}
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int fuzz_recv(void *ctx, unsigned char *buf, size_t len)
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33.8k
{
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    //reads from the buffer from fuzzer
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33.8k
    fuzzBufferOffset_t *biomemfuzz = (fuzzBufferOffset_t *) ctx;
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33.8k
    if (biomemfuzz->Offset == biomemfuzz->Size) {
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        //EOF
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1.66k
        return 0;
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1.66k
    }
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32.1k
    if (len > INT_MAX) {
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0
        return -1;
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0
    }
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32.1k
    if (len + biomemfuzz->Offset > biomemfuzz->Size) {
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        //do not overflow
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7.04k
        len = biomemfuzz->Size - biomemfuzz->Offset;
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7.04k
    }
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32.1k
    memcpy(buf, biomemfuzz->Data + biomemfuzz->Offset, len);
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32.1k
    biomemfuzz->Offset += len;
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32.1k
    return (int) len;
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32.1k
}
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int dummy_random(void *p_rng, unsigned char *output, size_t output_len)
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71.8k
{
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71.8k
    int ret;
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71.8k
    size_t i;
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71.8k
#if defined(MBEDTLS_CTR_DRBG_C)
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    //mbedtls_ctr_drbg_random requires a valid mbedtls_ctr_drbg_context in p_rng
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71.8k
    if (p_rng != NULL) {
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        //use mbedtls_ctr_drbg_random to find bugs in it
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71.8k
        ret = mbedtls_ctr_drbg_random(p_rng, output, output_len);
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71.8k
    } else {
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        //fall through to pseudo-random
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0
        ret = 0;
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0
    }
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#else
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    (void) p_rng;
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    ret = 0;
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#endif
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741k
    for (i = 0; i < output_len; i++) {
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        //replace result with pseudo random
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669k
        output[i] = (unsigned char) rand();
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669k
    }
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71.8k
    return ret;
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71.8k
}
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int dummy_entropy(void *data, unsigned char *output, size_t len)
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12.7k
{
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12.7k
    size_t i;
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12.7k
    (void) data;
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    //use mbedtls_entropy_func to find bugs in it
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    //test performance impact of entropy
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    //ret = mbedtls_entropy_func(data, output, len);
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626k
    for (i = 0; i < len; i++) {
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        //replace result with pseudo random
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613k
        output[i] = (unsigned char) rand();
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613k
    }
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12.7k
    return 0;
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12.7k
}
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int fuzz_recv_timeout(void *ctx, unsigned char *buf, size_t len,
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                      uint32_t timeout)
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9.16k
{
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9.16k
    (void) timeout;
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9.16k
    return fuzz_recv(ctx, buf, len);
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9.16k
}