config.c

DHCPv6协议在Linux操作系统下的一个客户端实现。

}

int
configure_global_option(void)
{
	struct cf_list *cl;

	/* DNS servers */
	if (cf_dns_list && dhcp6_mode != DHCP6_MODE_SERVER) {
		dprintf(LOG_INFO, "%s" "%s:%d server-only configuration",
		    FNAME, configfilename, cf_dns_list->line);
		goto bad;
	}
	TAILQ_INIT(&dnslist0);
	for (cl = cf_dns_list; cl; cl = cl->next) {
		/* duplication check */
		if (dhcp6_find_listval(&dnslist0, cl->ptr,
		    DHCP6_LISTVAL_ADDR6)) {
			dprintf(LOG_INFO, "%s"
			    "%s:%d duplicated DNS server: %s", FNAME,
			    configfilename, cl->line,
			    in6addr2str((struct in6_addr *)cl->ptr, 0));
			goto bad;
		}
		if (dhcp6_add_listval(&dnslist0, cl->ptr,
		    DHCP6_LISTVAL_ADDR6) == NULL) {
			dprintf(LOG_ERR, "%s" "failed to add a DNS server", 
				FNAME);
			goto bad;
		}
	}

	return 0;

  bad:
	return -1;
}

#if 0
/* we currently only construct EUI-64 based interface ID */
static int
get_default_ifid(pif)
	struct prefix_ifconf *pif;
{
	struct ifaddrs *ifa, *ifap;
	struct sockaddr *sdl;

	if (pif->ifid_len < 64) {
		dprintf(LOG_NOTICE, "%s" "ID length too short", FNAME);
		return -1;
	}

	if (getifaddrs(&ifap) < 0) {
		dprintf(LOG_ERR, "%s" "getifaddrs failed: %s",
			FNAME, strerror(errno));
		return -1;
	}
	
	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
		char *cp;

		if (strcmp(ifa->ifa_name, pif->ifname) != 0)
			continue;

		sdl = ifa->ifa_addr;
		if (sizeof(*sdl) < 6) {
			dprintf(LOG_NOTICE, "%s"
				"link layer address is too short (%s)",
				FNAME, pif->ifname);
			goto fail;
		}

		memset(pif->ifid, 0, sizeof(pif->ifid));
		cp = (char *)(sdl->sa_data + sizeof(*sdl));
		pif->ifid[8] = cp[0];
		pif->ifid[8] ^= 0x02; /* reverse the u/l bit*/
		pif->ifid[9] = cp[1];
		pif->ifid[10] = cp[2];
		pif->ifid[11] = 0xff;
		pif->ifid[12] = 0xfe;
		pif->ifid[13] = cp[3];
		pif->ifid[14] = cp[4];
		pif->ifid[15] = cp[5];

		break;
	}

	if (ifa == NULL) {
		dprintf(LOG_INFO, "%s"
			"cannot find interface information for %s",
			FNAME, pif->ifname);
		goto fail;
	}

	freeifaddrs(ifap);
	return (0);

  fail:
	freeifaddrs(ifap);
	return (-1);
}
#endif

void
configure_cleanup(void)
{
	clear_ifconf(dhcp6_ifconflist);
	dhcp6_ifconflist = NULL;
	clear_hostconf(host_conflist0);
	host_conflist0 = NULL;
	dhcp6_clear_list(&dnslist0);
	TAILQ_INIT(&dnslist0);
}

void
configure_commit(void)
{
	struct dhcp6_ifconf *ifc;
	struct dhcp6_if *ifp;

	/* commit interface configuration */
	for (ifc = dhcp6_ifconflist; ifc; ifc = ifc->next) {
		if ((ifp = find_ifconfbyname(ifc->ifname)) != NULL) {
			ifp->send_flags = ifc->send_flags;

			ifp->allow_flags = ifc->allow_flags;

			clear_options(ifp->send_options);

			ifp->send_options = ifc->send_options;
			ifc->send_options = NULL;

			dhcp6_clear_list(&ifp->reqopt_list);
			ifp->reqopt_list = ifc->reqopt_list;
			TAILQ_INIT(&ifc->reqopt_list);
			
			dhcp6_clear_list(&ifp->addr_list);
			ifp->addr_list = ifc->addr_list;
			TAILQ_INIT(&ifc->addr_list);

			dhcp6_clear_list(&ifp->prefix_list);
			ifp->prefix_list = ifc->prefix_list;
			TAILQ_INIT(&ifc->prefix_list);
			
			ifp->server_pref = ifc->server_pref;

			memcpy(&ifp->iaidinfo, &ifc->iaidinfo, sizeof(ifp->iaidinfo));
		}
	}
	clear_ifconf(dhcp6_ifconflist);

	/* commit prefix configuration */
	if (host_conflist) {
		/* clear previous configuration. (need more work?) */
		clear_hostconf(host_conflist);
	}
	host_conflist = host_conflist0;
	host_conflist0 = NULL;
}

static void
clear_ifconf(struct dhcp6_ifconf *iflist)
{
	struct dhcp6_ifconf *ifc, *ifc_next;

	for (ifc = iflist; ifc; ifc = ifc_next) {
		ifc_next = ifc->next;

		free(ifc->ifname);
		clear_options(ifc->send_options);
		dhcp6_clear_list(&ifc->reqopt_list);

		free(ifc);
	}
}

static void
clear_hostconf(struct host_conf *hlist)
{
	struct host_conf *host, *host_next;
	struct dhcp6_listval *p;

	for (host = hlist; host; host = host_next) {
		host_next = host->next;

		free(host->name);
		while ((p = TAILQ_FIRST(&host->prefix_list)) != NULL) {
			TAILQ_REMOVE(&host->prefix_list, p, link);
			free(p);
		}
		if (host->duid.duid_id)
			free(host->duid.duid_id);
		free(host);
	}
}

static void
clear_options(struct dhcp6_optconf *opt0)
{
	struct dhcp6_optconf *opt, *opt_next;

	for (opt = opt0; opt; opt = opt_next) {
		opt_next = opt->next;

		free(opt->val);
		free(opt);
	}
}

static int
add_options(int opcode,	struct dhcp6_ifconf *ifc,
	    struct cf_list *cfl0)
{
	struct dhcp6_listval *opt;
	struct cf_list *cfl;
	int opttype;

	for (cfl = cfl0; cfl; cfl = cfl->next) {
		if (opcode ==  DHCPOPTCODE_REQUEST) {
			for (opt = TAILQ_FIRST(&ifc->reqopt_list); opt;
			     opt = TAILQ_NEXT(opt, link)) {
				if (opt->val_num == cfl->type) {
					dprintf(LOG_INFO, "%s"
						"duplicated requested"
						" option: %s", FNAME,
						dhcp6optstr(cfl->type));
					goto next; /* ignore it */
				}
			}
		}

		switch(cfl->type) {
		case DHCPOPT_RAPID_COMMIT:
			switch(opcode) {
			case DHCPOPTCODE_SEND:
				ifc->send_flags |= DHCIFF_RAPID_COMMIT;
				break;
			case DHCPOPTCODE_ALLOW:
				ifc->allow_flags |= DHCIFF_RAPID_COMMIT;
				break;
			default:
				dprintf(LOG_ERR, "%s" "invalid operation (%d) "
					"for option type (%d)",
					FNAME, opcode, cfl->type);
				return (-1);
			}
			break;
		case DHCPOPT_PREFIX_DELEGATION:
			switch(opcode) {
			case DHCPOPTCODE_REQUEST:
				ifc->send_flags |= DHCIFF_PREFIX_DELEGATION;
				break;
			default:
				dprintf(LOG_ERR, "%s" "invalid operation (%d) "
					"for option type (%d)",
					FNAME, opcode, cfl->type);
				return (-1);
			}
			break;

		case DHCPOPT_DNS:
			switch(opcode) {
			case DHCPOPTCODE_REQUEST:
				opttype = DH6OPT_DNS_RESOLVERS;
				if (dhcp6_add_listval(&ifc->reqopt_list,
				    &opttype, DHCP6_LISTVAL_NUM) == NULL) {
					dprintf(LOG_ERR, "%s" "failed to "
					    "configure an option", FNAME);
					return (-1);
				}
				break;
			default:
				dprintf(LOG_ERR, "%s" "invalid operation (%d) "
					"for option type (%d)",
					FNAME, opcode, cfl->type);
				break;
			}
			break;
		default:
			dprintf(LOG_ERR, "%s"
				"unknown option type: %d", FNAME, cfl->type);
				return (-1);
		}

	next:;
	}

	return (0);
}

static int
add_address(struct dhcp6_list *addr_list,
	    struct dhcp6_addr *v6addr)
{
	struct dhcp6_listval *lv, *val;
	
	/* avoid invalid addresses */
	if (IN6_IS_ADDR_RESERVED(&v6addr->addr)) {
		dprintf(LOG_ERR, "%s" "invalid address: %s",
			FNAME, in6addr2str(&v6addr->addr, 0));
		return (-1);
	}

	/* address duplication check */
	for (lv = TAILQ_FIRST(addr_list); lv;
	     lv = TAILQ_NEXT(lv, link)) {
		if (IN6_ARE_ADDR_EQUAL(&lv->val_dhcp6addr.addr, &v6addr->addr) &&
		    lv->val_dhcp6addr.plen == v6addr->plen) {
			dprintf(LOG_ERR, "%s"
				"duplicated address: %s/%d ", FNAME,
				in6addr2str(&v6addr->addr, 0), v6addr->plen);
			return (-1);
		}
	}
	if ((val = (struct dhcp6_listval *)malloc(sizeof(*val))) == NULL)
		dprintf(LOG_ERR, "%s" "memory allocation failed", FNAME);
	memset(val, 0, sizeof(*val));
	memcpy(&val->val_dhcp6addr, v6addr, sizeof(val->val_dhcp6addr));
	dprintf(LOG_DEBUG, "%s" "add address: %s",
		FNAME, in6addr2str(&v6addr->addr, 0));
	TAILQ_INSERT_TAIL(addr_list, val, link);
	return (0);
}