view fuzz-harness.c @ 1715:3974f087d9c0

Disallow leading lines before the ident for server (#102) Per RFC4253 4.2 clients must be able to process other lines of data before the version string, server behavior is not defined neither with MUST/SHOULD nor with MAY. If server process up to 50 lines too - it may cause too long hanging session with invalid/evil client that consume host resources and potentially may lead to DDoS on poor embedded boxes. Let's require first line from client to be version string and fail early if it's not - matches both RFC and real OpenSSH behavior.
author Vladislav Grishenko <themiron@users.noreply.github.com>
date Mon, 15 Jun 2020 18:22:18 +0500
parents bff41a61a1b6
children dfbe947bdf0d
line wrap: on
line source

#include "includes.h"
#include "buffer.h"
#include "dbutil.h"

extern int LLVMFuzzerTestOneInput(const unsigned char *data, size_t size);

int main(int argc, char ** argv) {
    int i;
    buffer *input = buf_new(100000);

    for (i = 1; i < argc; i++) {
        printf("arg %s\n", argv[i]);
#if DEBUG_TRACE
        if (strcmp(argv[i], "-v") == 0) {
            debug_trace = 1;
            TRACE(("debug printing on"))
        }
#endif
    }

    int old_fuzz_wrapfds = 0;
    for (i = 1; i < argc; i++) {
        if (argv[i][0] == '-') {
            /* ignore arguments */
            continue;
        }

        char* fn = argv[i];
        buf_setlen(input, 0);
        buf_readfile(input, fn);
        buf_setpos(input, 0);

        fuzz.wrapfds = old_fuzz_wrapfds;
        printf("Running %s once \n", fn);
        LLVMFuzzerTestOneInput(input->data, input->len);
        printf("Running %s twice \n", fn);
        LLVMFuzzerTestOneInput(input->data, input->len);
        printf("Done %s\n", fn);

        /* Disable wrapfd so it won't interfere with buf_readfile() above */
        old_fuzz_wrapfds = fuzz.wrapfds;
        fuzz.wrapfds = 0;
    }

    printf("Finished\n");

    return 0;
}