Win32 version for using the registry or resolv.conf for resolver information

lib/lwres/win32/lwconfig.c

@@ -0,0 +1,153 @@
+/*
+ * Copyright (C) 2002 Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
+ * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
+ * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
+ * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
+ * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $Id: lwconfig.c,v 1.1 2002/08/11 03:29:32 mayer Exp $ */
+
+/*
+ * We do this so that we may incorporate everything in the main routines
+ * so that we can take advantage of the fixes and changes made there
+ * without having to add them twice. We can then call the parse routine
+ * if there is a resolv.conf file and fetch our own data from the
+ * Windows environment otherwise.
+ */
+
+/*
+ * Note that on Win32 there is normally no resolv.conf since all information
+ * is stored in the registry. Therefore there is no ordering like the
+ * contents of resolv.conf. Since the "search" or "domain" keyword, on
+ * Win32 if a search list is found it is used, otherwise the domain name
+ * is used since they are mutually exclusive. The search list can be entered
+ * in the DNS tab of the "Advanced TCP/IP settings" window under the same place
+ * that you add your nameserver list.
+ */
+
+#define lwres_conf_parse generic_lwres_conf_parse
+#include "../lwconfig.c"
+#undef lwres_conf_parse
+
+#include <iphlpapi.h>
+
+#define TCPIP_SUBKEY	\
+	"SYSTEM\\CurrentControlSet\\Services\\Tcpip\\Parameters"
+
+void
+get_win32_searchlist(lwres_context_t *ctx) {
+	HKEY hKey;
+	BOOL keyFound = TRUE;
+	char searchlist[MAX_PATH];
+	DWORD searchlen = MAX_PATH;
+	char *cp;
+	int idx;
+	lwres_conf_t *confdata;
+
+	REQUIRE(ctx != NULL);
+	confdata = &ctx->confdata;
+
+	memset(searchlist, 0, MAX_PATH);
+	if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, TCPIP_SUBKEY, 0, KEY_READ, &hKey)
+		!= ERROR_SUCCESS)
+		keyFound = FALSE;
+	
+	if (keyFound == TRUE) {
+		/* Get the named directory */
+		if (RegQueryValueEx(hKey, "SearchList", NULL, NULL,
+			(LPBYTE)searchlist, &searchlen) != ERROR_SUCCESS)
+			keyFound = FALSE;
+	}
+	
+	RegCloseKey(hKey);
+
+	confdata->searchnxt = 0;
+
+	idx = 0;
+	cp = strtok((char *)searchlist, ", \0");
+	while (cp != NULL) {
+		if (confdata->searchnxt == LWRES_CONFMAXSEARCH)
+			break;
+		if (strlen(cp) <= MAX_PATH && strlen(cp) > 0) {
+			confdata->search[idx] = lwres_strdup(ctx, cp);
+		}
+		idx++;
+		confdata->searchnxt++;
+		cp = strtok(NULL, ", \0");
+	}
+}
+
+lwres_result_t
+lwres_conf_parse(lwres_context_t *ctx, const char *filename) {
+	lwres_result_t ret = LWRES_R_SUCCESS;
+	lwres_result_t res;
+	lwres_conf_t *confdata;
+	FIXED_INFO * FixedInfo;
+	ULONG    BufLen = sizeof(FIXED_INFO);
+	DWORD    dwRetVal;
+	IP_ADDR_STRING *pIPAddr;
+
+	REQUIRE(ctx != NULL);
+	confdata = &ctx->confdata;
+	REQUIRE(confdata != NULL);
+
+	/* Use the resolver if there is one */
+	ret = generic_lwres_conf_parse(ctx, filename);
+	if (confdata->nsnext > 0)
+		return (ret);
+
+	/*
+	 * We didn't get any nameservers so we need to do this ourselves
+	 */
+	FixedInfo = (FIXED_INFO *) GlobalAlloc(GPTR, BufLen);
+	dwRetVal = GetNetworkParams(FixedInfo, &BufLen);
+	if (dwRetVal == ERROR_BUFFER_OVERFLOW) {
+		GlobalFree(FixedInfo);
+		FixedInfo = GlobalAlloc(GPTR, BufLen);
+		dwRetVal = GetNetworkParams(FixedInfo, &BufLen);
+	}
+	if (dwRetVal != ERROR_SUCCESS) {
+		GlobalFree(FixedInfo);
+		return (LWRES_R_FAILURE);
+	}
+
+	/* Get the search list from the registry */
+	get_win32_searchlist(ctx);
+
+	/* Use only if there is no search list */
+	if (confdata->searchnxt == 0) {
+		confdata->domainname = lwres_strdup(ctx, FixedInfo->DomainName);
+		if (confdata->domainname == NULL) {
+			GlobalFree(FixedInfo);
+			return (LWRES_R_FAILURE);
+		}
+	}
+
+	/* Get the list of nameservers */
+	pIPAddr = &FixedInfo->DnsServerList;
+	while (pIPAddr) {
+		if (confdata->nsnext >= LWRES_CONFMAXNAMESERVERS)
+			break;
+
+		res = lwres_create_addr(pIPAddr->IpAddress.String,
+				&confdata->nameservers[confdata->nsnext++], 1);
+		if (res != LWRES_R_SUCCESS) {
+			GlobalFree(FixedInfo);
+			return (res);
+		}
+		pIPAddr = pIPAddr ->Next;
+	}
+
+	GlobalFree(FixedInfo);
+	return (ret);
+}