zzuf/src/network.c

/*
 *  zzuf - general purpose fuzzer
 *  Copyright (c) 2006-2009 Sam Hocevar <sam@hocevar.net>
 *                All Rights Reserved
 *
 *  $Id$
 *
 *  This program is free software. It comes without any warranty, to
 *  the extent permitted by applicable law. You can redistribute it
 *  and/or modify it under the terms of the Do What The Fuck You Want
 *  To Public License, Version 2, as published by Sam Hocevar. See
 *  http://sam.zoy.org/wtfpl/COPYING for more details.
 */

/*
 *  network.c: network connection helper functions
 */

#include "config.h"

#if defined HAVE_STDINT_H
#   include <stdint.h>
#elif defined HAVE_INTTYPES_H
#   include <inttypes.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if defined HAVE_SYS_SOCKET_H
#   include <sys/socket.h>
#   include <netinet/in.h>
#   include <arpa/inet.h>
#endif

#include "libzzuf.h"
#include "debug.h"
#include "ranges.h"
#include "network.h"

#if defined HAVE_SYS_SOCKET_H
static unsigned int get_socket_ip(int);
static int host_in_list(unsigned int, unsigned int const *);
static unsigned int *create_host_list(char const *, unsigned int *);

/* Network IP cherry picking */
static unsigned int *allow = NULL;
static unsigned int static_allow[512];
static unsigned int *deny = NULL;
static unsigned int static_deny[512];

/* Network port cherry picking */
static int *ports = NULL;
static int static_ports[512];
#endif

void _zz_network_init(void)
{
    ;
}

void _zz_network_fini(void)
{
#if defined HAVE_SYS_SOCKET_H
    if(ports != static_ports)
        free(ports);
    if(allow != static_allow)
        free(allow);
    if(deny != static_deny)
        free(deny);
#endif
}

void _zz_allow(char const *allowlist)
{
#if defined HAVE_SYS_SOCKET_H
    allow = create_host_list(allowlist, static_allow);
#endif
}

void _zz_deny(char const *denylist)
{
#if defined HAVE_SYS_SOCKET_H
    deny = create_host_list(denylist, static_deny);
#endif
}

void _zz_ports(char const *portlist)
{
#if defined HAVE_SYS_SOCKET_H
    ports = _zz_allocrange(portlist, static_ports);
#endif
}

int _zz_portwatched(int port)
{
#if defined HAVE_SYS_SOCKET_H
    if(!ports)
        return 1;

    return _zz_isinrange(port, ports);
#else
    return 0;
#endif
}

int _zz_hostwatched(int sock)
{
#if defined HAVE_SYS_SOCKET_H
    int watch = 1;
    unsigned int ip;

    if(!allow && !deny)
        return 1;

    ip = get_socket_ip(sock);

    if(deny && host_in_list(ip, deny))
        watch = 0;
    if(allow)
        watch = host_in_list(ip, allow);

    return watch;
#else
    return 0;
#endif
}

/* XXX: the following functions are local */

#if defined HAVE_SYS_SOCKET_H
static unsigned int *create_host_list(char const *list,
                                      unsigned int *static_list)
{
    int ret;
    char *copy;
    char *parser;
    struct in_addr addr;
    unsigned int i, chunks, len, *iplist;

    len = strlen(list);
    copy = malloc(len + 1);
    if (!copy) {
        // TODO better error handling
        perror("malloc");
        exit(EXIT_FAILURE);
    }
    strncpy(copy, list, len);
    copy[len] = 0;

    /* Count commas */
    for(parser = copy, chunks = 1; *parser; parser++)
        if(*parser == ',')
            chunks++;

    if(chunks >= 512)
        iplist = malloc((chunks + 1) * sizeof(unsigned int));
    else
        iplist = static_list;

    for(parser = copy, i = 0; i < chunks; i++)
    {
        char *comma = strchr(parser, ',');
        if (comma)
            *comma = 0;

        ret = inet_aton(parser, &addr);
        if (ret)
            iplist[i] = addr.s_addr;
        else {
            i--;
            chunks--;
            debug("create_host_list: Invalid IP address '%s'. Skipping it.", parser);
        }
        parser = comma + 1;
    }

    iplist[i] = 0;
    free(copy);

    return iplist;
}

static int host_in_list(unsigned int value, unsigned int const *list)
{
    unsigned int i;

    if (!value || !list)
        return 0;

    for (i = 0; list[i]; i++)
        if (value == list[i])
            return 1;

    return 0;
}

static unsigned int get_socket_ip(int sock)
{
    int ret;
    struct sockaddr_in sin;
    socklen_t len = sizeof(sin);

    // Probably not a socket descriptor
    if (sock < 3)
        return 0;

    memset(&sin, 0, sizeof(sin));
    ret = getsockname(sock, &sin, &len);
    if (ret) {
        // TODO error handling
        return 0;
    }

    return sin.sin_addr.s_addr;
}
#endif /* HAVE_SYS_SOCKET_H */