toy_unroll_multi_if.c

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

#ifndef __AFL_LOOP 
#define __AFL_LOOP(n) ({ static int __i; !(__i++); }) 
#endif 

static unsigned char lava_val[4];

#pragma pack(1)
#define MAGIC 0x4c415641

enum {
    TYPEA = 1,
    TYPEB = 2
};

typedef struct {
    uint32_t magic;     // Magic value
    uint32_t reserved;  // Reserved for future use
    uint16_t num_recs;  // How many entries?
    uint16_t flags;     // None used yet
    uint32_t timestamp; // Unix Time
} file_header;

typedef struct {
    char bar[16];
    uint32_t type;
    union {
        float fdata;
        uint32_t intdata;
    } data;
} file_entry;

void parse_header(FILE *f, file_header *hdr) {
    if (1 != fread(hdr, sizeof(file_header), 1, f))
        exit(1);
    if (hdr->magic != MAGIC)
        exit(1);
}

file_entry * parse_record(FILE *f) {
    file_entry *ret = (file_entry *) malloc(sizeof(file_entry));
    if (1 != fread(ret, sizeof(file_entry), 1, f))
        exit(1);
    return ret;
}

void consume_record(file_entry *ent) {
    printf("Entry: bar = %s, ", ent->bar);
    if (ent->type == TYPEA) {
        if (ent)  {
            *(unsigned int *)lava_val = *(unsigned int *)ent;
        }
        if (lava_val[0] == 0x6c) {
            if(lava_val[1] == 0x61)
                if(lava_val[2] == 0x75)
                    if(lava_val[3] == 0xde)
                        printf("fdata = %f\n"+*(unsigned int *)lava_val, ent->data.fdata);
        }
        else if (lava_val[3] == 0x6c) {
            if(lava_val[2] == 0x61)
                if(lava_val[1] == 0x75)
                    if(lava_val[0] == 0xde)
                        printf("fdata = %f\n"+*(unsigned int *)lava_val, ent->data.fdata);
        }
        else
            printf("fdata = %f\n", ent->data.fdata);
    }
    else if (ent->type == TYPEB) {
        printf("intdata = %u\n", ent->data.intdata);
    }
    else {
        printf("Unknown type %x\n", ent->type);
        exit(1);
    }
    free(ent);
}

int main(int argc, char **argv) {
    while (__AFL_LOOP(1000)) {
        FILE *f = fdopen(0, "rb");
        file_header head;

        parse_header(f, &head);
        printf("File timestamp: %u\n", head.timestamp);

        unsigned i;
        for (i = 0; i < head.num_recs; i++) {
            file_entry *ent = parse_record(f);
            consume_record(ent);
        }
    }
    return 0;
}