diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c index 80ae695..9eeaed0 100644 --- a/src/openvpn/tun.c +++ b/src/openvpn/tun.c @@ -149,6 +149,61 @@ out: } static bool +do_dns_domain_service(bool add, const struct tuntap *tt) +{ + bool ret = false; + ack_message_t ack; + struct gc_arena gc = gc_new(); + HANDLE pipe = tt->options.msg_channel; + + if (!tt->options.domain) /* no domain to add or delete */ + { + return true; + } + + /* Use dns_cfg_msg with addr_len = 0 for setting only the DOMAIN */ + dns_cfg_message_t dns = { + .header = { + (add ? msg_add_dns_cfg : msg_del_dns_cfg), + sizeof(dns_cfg_message_t), + 0 + }, + .iface = { .index = tt->adapter_index, .name = "" }, + .domains = "", /* set below */ + .family = AF_INET, /* unused */ + .addr_len = 0 /* add/delete only the domain, not DNS servers */ + }; + + strncpynt(dns.iface.name, tt->actual_name, sizeof(dns.iface.name)); + strncpynt(dns.domains, tt->options.domain, sizeof(dns.domains)); + /* truncation of domain name is not checked as it can't happen + * with 512 bytes room in dns.domains. + */ + + msg(D_LOW, "%s dns domain on '%s' (if_index = %d) using service", + (add ? "Setting" : "Deleting"), dns.iface.name, dns.iface.index); + if (!send_msg_iservice(pipe, &dns, sizeof(dns), &ack, "TUN")) + { + goto out; + } + + if (ack.error_number != NO_ERROR) + { + msg(M_WARN, "TUN: %s dns domain failed using service: %s [status=%u if_name=%s]", + (add ? "adding" : "deleting"), strerror_win32(ack.error_number, &gc), + ack.error_number, dns.iface.name); + goto out; + } + + msg(M_INFO, "DNS domain %s using service", (add ? "set" : "deleted")); + ret = true; + +out: + gc_free(&gc); + return ret; +} + +static bool do_dns_service(bool add, const short family, const struct tuntap *tt) { bool ret = false; @@ -164,6 +219,7 @@ do_dns_service(bool add, const short family, const struct tuntap *tt) return true; } + /* Use dns_cfg_msg with domain = "" for setting only the DNS servers */ dns_cfg_message_t dns = { .header = { (add ? msg_add_dns_cfg : msg_del_dns_cfg), @@ -1100,6 +1156,11 @@ do_ifconfig_ipv6(struct tuntap *tt, const char *ifname, int tun_mtu, } do_dns_service(true, AF_INET6, tt); do_set_mtu_service(tt, AF_INET6, tun_mtu); + /* If IPv4 is not enabled, set DNS domain here */ + if (!tt->did_ifconfig_setup) + { + do_dns_domain_service(true, tt); + } } else { @@ -1485,6 +1546,7 @@ do_ifconfig_ipv4(struct tuntap *tt, const char *ifname, int tun_mtu, { do_address_service(true, AF_INET, tt); do_dns_service(true, AF_INET, tt); + do_dns_domain_service(true, tt); } else if (tt->options.ip_win32_type == IPW32_SET_NETSH) { @@ -6761,6 +6823,11 @@ close_tun(struct tuntap *tt, openvpn_net_ctx_t *ctx) } else if (tt->options.msg_channel) { + /* If IPv4 is not enabled, delete DNS domain here */ + if (!tt->did_ifconfig_setup) + { + do_dns_domain_service(false, tt); + } if (tt->options.dns6_len > 0) { do_dns_service(false, AF_INET6, tt); @@ -6786,6 +6853,7 @@ close_tun(struct tuntap *tt, openvpn_net_ctx_t *ctx) } else if (tt->options.msg_channel) { + do_dns_domain_service(false, tt); do_dns_service(false, AF_INET, tt); do_address_service(false, AF_INET, tt); } diff --git a/src/openvpnserv/interactive.c b/src/openvpnserv/interactive.c index 207cc4a..1793caf 100644 --- a/src/openvpnserv/interactive.c +++ b/src/openvpnserv/interactive.c @@ -91,6 +91,7 @@ typedef enum { block_dns, undo_dns4, undo_dns6, + undo_domain, _undo_type_max } undo_type_t; typedef list_item_t *undo_lists_t[_undo_type_max]; @@ -564,6 +565,24 @@ InterfaceLuid(const char *iface_name, PNET_LUID luid) return status; } +static DWORD +ConvertInterfaceNameToIndex(const wchar_t *ifname, NET_IFINDEX *index) +{ + NET_LUID luid; + DWORD err; + + err = ConvertInterfaceAliasToLuid(ifname, &luid); + if (err == ERROR_SUCCESS) + { + err = ConvertInterfaceLuidToIndex(&luid, index); + } + if (err != ERROR_SUCCESS) + { + MsgToEventLog(M_ERR, L"Failed to find interface index for <%s>", ifname); + } + return err; +} + static BOOL CmpAddress(LPVOID item, LPVOID address) { @@ -1057,6 +1076,53 @@ out: return err; } +/** + * Run command: wmic nicconfig (InterfaceIndex=$if_index) call $action ($data) + * @param if_index "index of interface" + * @param action e.g., "SetDNSDomain" + * @param data data if required for action + * - a single word for SetDNSDomain, empty or NULL to delete + * - comma separated values for a list + */ +static DWORD +wmic_nicconfig_cmd(const wchar_t *action, const NET_IFINDEX if_index, + const wchar_t *data) +{ + DWORD err = 0; + wchar_t argv0[MAX_PATH]; + wchar_t *cmdline = NULL; + int timeout = 10000; /* in msec */ + + swprintf(argv0, _countof(argv0), L"%s\\%s", get_win_sys_path(), L"wbem\\wmic.exe"); + argv0[_countof(argv0) - 1] = L'\0'; + + const wchar_t *fmt; + /* comma separated list must be enclosed in parenthesis */ + if (data && wcschr(data, L',')) + { + fmt = L"wmic nicconfig where (InterfaceIndex=%ld) call %s (%s)"; + } + else + { + fmt = L"wmic nicconfig where (InterfaceIndex=%ld) call %s %s"; + } + + size_t ncmdline = wcslen(fmt) + 20 + wcslen(action) /* max 20 for ifindex */ + + (data ? wcslen(data) + 1 : 1); + cmdline = malloc(ncmdline*sizeof(wchar_t)); + if (!cmdline) + { + return ERROR_OUTOFMEMORY; + } + + openvpn_sntprintf(cmdline, ncmdline, fmt, if_index, action, + data? data : L""); + err = ExecCommand(argv0, cmdline, timeout); + + free(cmdline); + return err; +} + /* Delete all IPv4 or IPv6 dns servers for an interface */ static DWORD DeleteDNS(short family, wchar_t *if_name) @@ -1079,6 +1145,54 @@ CmpWString(LPVOID item, LPVOID str) return (wcscmp(item, str) == 0) ? TRUE : FALSE; } +/** + * Set interface specific DNS domain suffix + * @param if_name name of the the interface + * @param domain a single domain name + * @param lists pointer to the undo lists. If NULL + * undo lists are not altered. + * Will delete the currently set value if domain is empty. + */ +static DWORD +SetDNSDomain(const wchar_t *if_name, const char *domain, undo_lists_t *lists) +{ + NET_IFINDEX if_index; + + DWORD err = ConvertInterfaceNameToIndex(if_name, &if_index); + if (err != ERROR_SUCCESS) + { + return err; + } + + wchar_t *wdomain = utf8to16(domain); /* utf8 to wide-char */ + if (!wdomain) + { + return ERROR_OUTOFMEMORY; + } + + /* free undo list if previously set */ + if (lists) + { + free(RemoveListItem(&(*lists)[undo_domain], CmpWString, (void *)if_name)); + } + + err = wmic_nicconfig_cmd(L"SetDNSDomain", if_index, wdomain); + + /* Add to undo list if domain is non-empty */ + if (err == 0 && wdomain[0] && lists) + { + wchar_t *tmp_name = wcsdup(if_name); + if (!tmp_name || AddListItem(&(*lists)[undo_domain], tmp_name)) + { + free(tmp_name); + err = ERROR_OUTOFMEMORY; + } + } + + free(wdomain); + return err; +} + static DWORD HandleDNSConfigMessage(const dns_cfg_message_t *msg, undo_lists_t *lists) { @@ -1098,6 +1212,13 @@ HandleDNSConfigMessage(const dns_cfg_message_t *msg, undo_lists_t *lists) return ERROR_MESSAGE_DATA; } + /* use a non-const reference with limited scope to enforce null-termination of strings from client */ + { + dns_cfg_message_t *msgptr = (dns_cfg_message_t *) msg; + msgptr->iface.name[_countof(msg->iface.name)-1] = '\0'; + msgptr->domains[_countof(msg->domains)-1] = '\0'; + } + wchar_t *wide_name = utf8to16(msg->iface.name); /* utf8 to wide-char */ if (!wide_name) { @@ -1117,9 +1238,14 @@ HandleDNSConfigMessage(const dns_cfg_message_t *msg, undo_lists_t *lists) free(RemoveListItem(&(*lists)[undo_type], CmpWString, wide_name)); } - if (msg->header.type == msg_del_dns_cfg) /* job done */ + if (msg->header.type == msg_del_dns_cfg) { - goto out; + if (msg->domains[0]) + { + /* setting an empty domain removes any previous value */ + err = SetDNSDomain(wide_name, "", lists); + } + goto out; /* job done */ } for (int i = 0; i < addr_len; ++i) @@ -1142,6 +1268,8 @@ HandleDNSConfigMessage(const dns_cfg_message_t *msg, undo_lists_t *lists) */ } + err = 0; + if (msg->addr_len > 0) { wchar_t *tmp_name = wcsdup(wide_name); @@ -1154,7 +1282,9 @@ HandleDNSConfigMessage(const dns_cfg_message_t *msg, undo_lists_t *lists) } } - err = 0; + if (msg->domains[0]) { + err = SetDNSDomain(wide_name, msg->domains, lists); + } out: free(wide_name); @@ -1445,6 +1575,10 @@ Undo(undo_lists_t *lists) DeleteDNS(AF_INET6, item->data); break; + case undo_domain: + SetDNSDomain(item->data, "", NULL); + break; + case block_dns: interface_data = (block_dns_data_t *)(item->data); delete_block_dns_filters(interface_data->engine);