dhclient.c

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	}

#if 0
	if (lease->filename)
		script_set_env(ip->client, prefix, "filename", lease->filename);
	if (lease->server_name)
		script_set_env(ip->client, prefix, "server_name",
		    lease->server_name);
#endif

	for (i = 0; i < 256; i++) {
		u_int8_t *dp = NULL;

		if (ip->client->config->defaults[i].len) {
			if (lease->options[i].len) {
				switch (
				    ip->client->config->default_actions[i]) {
				case ACTION_DEFAULT:
					dp = lease->options[i].data;
					len = lease->options[i].len;
					break;
				case ACTION_SUPERSEDE:
supersede:
					dp = ip->client->
						config->defaults[i].data;
					len = ip->client->
						config->defaults[i].len;
					break;
				case ACTION_PREPEND:
					len = ip->client->
					    config->defaults[i].len +
					    lease->options[i].len;
					if (len > sizeof(dbuf)) {
						warning("no space to %s %s",
						    "prepend option",
						    dhcp_options[i].name);
						goto supersede;
					}
					dp = dbuf;
					memcpy(dp,
						ip->client->
						config->defaults[i].data,
						ip->client->
						config->defaults[i].len);
					memcpy(dp + ip->client->
						config->defaults[i].len,
						lease->options[i].data,
						lease->options[i].len);
					dp[len] = '\0';
					break;
				case ACTION_APPEND:
					len = ip->client->
					    config->defaults[i].len +
					    lease->options[i].len;
					if (len > sizeof(dbuf)) {
						warning("no space to %s %s",
						    "append option",
						    dhcp_options[i].name);
						goto supersede;
					}
					dp = dbuf;
					memcpy(dp,
						lease->options[i].data,
						lease->options[i].len);
					memcpy(dp + lease->options[i].len,
						ip->client->
						config->defaults[i].data,
						ip->client->
						config->defaults[i].len);
					dp[len] = '\0';
				}
			} else {
				dp = ip->client->
					config->defaults[i].data;
				len = ip->client->
					config->defaults[i].len;
			}
		} else if (lease->options[i].len) {
			len = lease->options[i].len;
			dp = lease->options[i].data;
		} else {
			len = 0;
		}
#if 0
		if (len) {
			char name[256];

			if (dhcp_option_ev_name(name, sizeof(name),
			    &dhcp_options[i]))
				script_set_env(ip->client, prefix, name,
				    pretty_print_option(i, dp, len, 0, 0));
		}
#endif
	}
#if 0
	snprintf(tbuf, sizeof(tbuf), "%d", (int)lease->expiry);
	script_set_env(ip->client, prefix, "expiry", tbuf);
#endif
}

void
script_write_params(char *prefix, struct client_lease *lease)
{
	size_t		 fn_len = 0, sn_len = 0, pr_len = 0;
	struct imsg_hdr	 hdr;
	struct buf	*buf;
	int		 errs, i;

	if (lease->filename != NULL)
		fn_len = strlen(lease->filename);
	if (lease->server_name != NULL)
		sn_len = strlen(lease->server_name);
	if (prefix != NULL)
		pr_len = strlen(prefix);

	hdr.code = IMSG_SCRIPT_WRITE_PARAMS;
	hdr.len = sizeof(hdr) + sizeof(struct client_lease) +
	    sizeof(size_t) + fn_len + sizeof(size_t) + sn_len +
	    sizeof(size_t) + pr_len;

	for (i = 0; i < 256; i++)
		hdr.len += sizeof(int) + lease->options[i].len;

	scripttime = time(NULL);

	if ((buf = buf_open(hdr.len)) == NULL)
		error("buf_open: %m");

	errs = 0;
	errs += buf_add(buf, &hdr, sizeof(hdr));
	errs += buf_add(buf, lease, sizeof(struct client_lease));
	errs += buf_add(buf, &fn_len, sizeof(fn_len));
	errs += buf_add(buf, lease->filename, fn_len);
	errs += buf_add(buf, &sn_len, sizeof(sn_len));
	errs += buf_add(buf, lease->server_name, sn_len);
	errs += buf_add(buf, &pr_len, sizeof(pr_len));
	errs += buf_add(buf, prefix, pr_len);

	for (i = 0; i < 256; i++) {
		errs += buf_add(buf, &lease->options[i].len,
		    sizeof(lease->options[i].len));
		errs += buf_add(buf, lease->options[i].data,
		    lease->options[i].len);
	}

	if (errs)
		error("buf_add: %m");

	if (buf_close(privfd, buf) == -1)
		error("buf_close: %m");
}

int
dhcp_option_ev_name(char *buf, size_t buflen, struct dhcp_option *option)
{
	int i;

	for (i = 0; option->name[i]; i++) {
		if (i + 1 == buflen)
			return 0;
		if (option->name[i] == '-')
			buf[i] = '_';
		else
			buf[i] = option->name[i];
	}

	buf[i] = 0;
	return 1;
}

#if 0
void
go_daemon(void)
{
	static int state = 0;

	if (no_daemon || state)
		return;

	state = 1;

	/* Stop logging to stderr... */
	log_perror = 0;

	if (daemon(1, 0) == -1)
		error("daemon");

	/* we are chrooted, daemon(3) fails to open /dev/null */
	if (nullfd != -1) {
		dup2(nullfd, STDIN_FILENO);
		dup2(nullfd, STDOUT_FILENO);
		dup2(nullfd, STDERR_FILENO);
		close(nullfd);
		nullfd = -1;
	}
}
#endif

int
check_option(struct client_lease *l, int option)
{
	char *opbuf;
	char *sbuf;

	/* we use this, since this is what gets passed to dhclient-script */

	opbuf = pretty_print_option(option, l->options[option].data,
	    l->options[option].len, 0, 0);

	sbuf = option_as_string(option, l->options[option].data,
	    l->options[option].len);

	switch (option) {
	case DHO_SUBNET_MASK:
	case DHO_TIME_SERVERS:
	case DHO_NAME_SERVERS:
	case DHO_ROUTERS:
	case DHO_DOMAIN_NAME_SERVERS:
	case DHO_LOG_SERVERS:
	case DHO_COOKIE_SERVERS:
	case DHO_LPR_SERVERS:
	case DHO_IMPRESS_SERVERS:
	case DHO_RESOURCE_LOCATION_SERVERS:
	case DHO_SWAP_SERVER:
	case DHO_BROADCAST_ADDRESS:
	case DHO_NIS_SERVERS:
	case DHO_NTP_SERVERS:
	case DHO_NETBIOS_NAME_SERVERS:
	case DHO_NETBIOS_DD_SERVER:
	case DHO_FONT_SERVERS:
	case DHO_DHCP_SERVER_IDENTIFIER:
		if (!ipv4addrs(opbuf)) {
                        warning("Invalid IP address in option(%d): %s", option, opbuf);
			return (0);
		}
		return (1)  ;
	case DHO_HOST_NAME:
	case DHO_DOMAIN_NAME:
	case DHO_NIS_DOMAIN:
		if (!res_hnok(sbuf)) {
			warning("Bogus Host Name option %d: %s (%s)", option,
			    sbuf, opbuf);
			return (0);
		}
		return (1);
	case DHO_PAD:
	case DHO_TIME_OFFSET:
	case DHO_BOOT_SIZE:
	case DHO_MERIT_DUMP:
	case DHO_ROOT_PATH:
	case DHO_EXTENSIONS_PATH:
	case DHO_IP_FORWARDING:
	case DHO_NON_LOCAL_SOURCE_ROUTING:
	case DHO_POLICY_FILTER:
	case DHO_MAX_DGRAM_REASSEMBLY:
	case DHO_DEFAULT_IP_TTL:
	case DHO_PATH_MTU_AGING_TIMEOUT:
	case DHO_PATH_MTU_PLATEAU_TABLE:
	case DHO_INTERFACE_MTU:
	case DHO_ALL_SUBNETS_LOCAL:
	case DHO_PERFORM_MASK_DISCOVERY:
	case DHO_MASK_SUPPLIER:
	case DHO_ROUTER_DISCOVERY:
	case DHO_ROUTER_SOLICITATION_ADDRESS:
	case DHO_STATIC_ROUTES:
	case DHO_TRAILER_ENCAPSULATION:
	case DHO_ARP_CACHE_TIMEOUT:
	case DHO_IEEE802_3_ENCAPSULATION:
	case DHO_DEFAULT_TCP_TTL:
	case DHO_TCP_KEEPALIVE_INTERVAL:
	case DHO_TCP_KEEPALIVE_GARBAGE:
	case DHO_VENDOR_ENCAPSULATED_OPTIONS:
	case DHO_NETBIOS_NODE_TYPE:
	case DHO_NETBIOS_SCOPE:
	case DHO_X_DISPLAY_MANAGER:
	case DHO_DHCP_REQUESTED_ADDRESS:
	case DHO_DHCP_LEASE_TIME:
	case DHO_DHCP_OPTION_OVERLOAD:
	case DHO_DHCP_MESSAGE_TYPE:
	case DHO_DHCP_PARAMETER_REQUEST_LIST:
	case DHO_DHCP_MESSAGE:
	case DHO_DHCP_MAX_MESSAGE_SIZE:
	case DHO_DHCP_RENEWAL_TIME:
	case DHO_DHCP_REBINDING_TIME:
	case DHO_DHCP_CLASS_IDENTIFIER:
	case DHO_DHCP_CLIENT_IDENTIFIER:
	case DHO_DHCP_USER_CLASS_ID:
	case DHO_END:
		return (1);
	default:
		warning("unknown dhcp option value 0x%x", option);
		return (unknown_ok);
	}
}

int
res_hnok(const char *dn)
{
	int pch = PERIOD, ch = *dn++;

	while (ch != '\0') {
		int nch = *dn++;

		if (periodchar(ch)) {
			;
		} else if (periodchar(pch)) {
			if (!borderchar(ch))
				return (0);
		} else if (periodchar(nch) || nch == '\0') {
			if (!borderchar(ch))
				return (0);
		} else {
			if (!middlechar(ch))
				return (0);
		}
		pch = ch, ch = nch;
	}
	return (1);
}

/* Does buf consist only of dotted decimal ipv4 addrs?
 * return how many if so,
 * otherwise, return 0
 */
int
ipv4addrs(char * buf)
{
    char *tmp;
    struct in_addr jnk;
    int i = 0;

    note("Input: %s", buf);

    do {
        tmp = strtok(buf, " ");
        note("got %s", tmp);
		if( tmp && inet_aton(tmp, &jnk) ) i++;
        buf = NULL;
    } while( tmp );

    return (i);
}


char *
option_as_string(unsigned int code, unsigned char *data, int len)
{
	static char optbuf[32768]; /* XXX */
	char *op = optbuf;
	int opleft = sizeof(optbuf);
	unsigned char *dp = data;

	if (code > 255)
		error("option_as_string: bad code %d", code);

	for (; dp < data + len; dp++) {
		if (!isascii(*dp) || !isprint(*dp)) {
			if (dp + 1 != data + len || *dp != 0) {
				_snprintf(op, opleft, "\\%03o", *dp);
				op += 4;
				opleft -= 4;
			}
		} else if (*dp == '"' || *dp == '\'' || *dp == '$' ||
		    *dp == '`' || *dp == '\\') {
			*op++ = '\\';
			*op++ = *dp;
			opleft -= 2;
		} else {
			*op++ = *dp;
			opleft--;
		}
	}
	if (opleft < 1)
		goto toobig;
	*op = 0;
	return optbuf;
toobig:
	warning("dhcp option too large");
	return "<error>";
}

#if 0
int
fork_privchld(int fd, int fd2)
{
	struct pollfd pfd[1];
	int nfds;

	switch (fork()) {
	case -1:
		error("cannot fork");
	case 0:
		break;
	default:
		return (0);
	}

	setproctitle("%s [priv]", ifi->name);

	dup2(nullfd, STDIN_FILENO);
	dup2(nullfd, STDOUT_FILENO);
	dup2(nullfd, STDERR_FILENO);
	close(nullfd);
	close(fd2);

	for (;;) {
		pfd[0].fd = fd;
		pfd[0].events = POLLIN;
		if ((nfds = poll(pfd, 1, INFTIM)) == -1)
			if (errno != EINTR)
				error("poll error");

		if (nfds == 0 || !(pfd[0].revents & POLLIN))
			continue;

		dispatch_imsg(fd);
	}
}
#endif