/*
* reslist.c - get nameservers from windows *
*
* ircd-ratbox related changes are as follows
*
* Copyright (C) 2008 Aaron Sethman <androsyn@ratbox.org>
* Copyright (C) 2008-2012 ircd-ratbox development team
*
* pretty much all of this was yanked from c-ares ares_init.c here is the original
* header from there --
*
* Id: ares_init.c,v 1.72 2008-05-15 00:00:19 yangtse Exp $
* Copyright 1998 by the Massachusetts Institute of Technology.
* Copyright (C) 2007-2008 by Daniel Stenberg
*
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
* fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright
* notice and this permission notice appear in supporting
* documentation, and that the name of M.I.T. not be used in
* advertising or publicity pertaining to distribution of the
* software without specific, written prior permission.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is"
* without express or implied warranty.
*
*
*/
#ifdef _WIN32
#include <rb_lib.h>
#include <windows.h>
#include <iphlpapi.h>
const char *get_windows_nameservers(void);
#define IS_NT() ((int)GetVersion() > 0)
#define WIN_NS_9X "System\\CurrentControlSet\\Services\\VxD\\MSTCP"
#define WIN_NS_NT_KEY "System\\CurrentControlSet\\Services\\Tcpip\\Parameters"
#define NAMESERVER "NameServer"
#define DHCPNAMESERVER "DhcpNameServer"
#define DATABASEPATH "DatabasePath"
#define WIN_PATH_HOSTS "\\hosts"
static int
get_iphlpapi_dns_info(char *ret_buf, size_t ret_size)
{
FIXED_INFO *fi = alloca(sizeof(*fi));
DWORD size = sizeof(*fi);
typedef DWORD(WINAPI * get_net_param_func) (FIXED_INFO *, DWORD *);
get_net_param_func xxGetNetworkParams; /* available only on Win-98/2000+ */
HMODULE handle;
IP_ADDR_STRING *ipAddr;
int i, count = 0;
int debug = 0;
size_t ip_size = sizeof("255.255.255.255,") - 1;
size_t left = ret_size;
char *ret = ret_buf;
HRESULT res;
if(!fi)
return (0);
handle = LoadLibrary("iphlpapi.dll");
if(!handle)
return (0);
xxGetNetworkParams = (get_net_param_func) GetProcAddress(handle, "GetNetworkParams");
if(!xxGetNetworkParams)
goto quit;
res = (*xxGetNetworkParams) (fi, &size);
if((res != ERROR_BUFFER_OVERFLOW) && (res != ERROR_SUCCESS))
goto quit;
fi = alloca(size);
if(!fi || (*xxGetNetworkParams) (fi, &size) != ERROR_SUCCESS)
goto quit;
if(debug)
{
printf("Host Name: %s\n", fi->HostName);
printf("Domain Name: %s\n", fi->DomainName);
printf("DNS Servers:\n" " %s (primary)\n", fi->DnsServerList.IpAddress.String);
}
if(strlen(fi->DnsServerList.IpAddress.String) > 0 &&
inet_addr(fi->DnsServerList.IpAddress.String) != INADDR_NONE && left > ip_size)
{
ret += sprintf(ret, "%s,", fi->DnsServerList.IpAddress.String);
left -= ret - ret_buf;
count++;
}
for(i = 0, ipAddr = fi->DnsServerList.Next; ipAddr && left > ip_size;
ipAddr = ipAddr->Next, i++)
{
if(inet_addr(ipAddr->IpAddress.String) != INADDR_NONE)
{
ret += sprintf(ret, "%s,", ipAddr->IpAddress.String);
left -= ret - ret_buf;
count++;
}
if(debug)
printf(" %s (secondary %d)\n", ipAddr->IpAddress.String, i + 1);
}
quit:
if(handle)
FreeLibrary(handle);
if(debug && left <= ip_size)
printf("Too many nameservers. Truncating to %d addressess", count);
if(ret > ret_buf)
ret[-1] = '\0';
return (count);
}
/*
* Warning: returns a dynamically allocated buffer, the user MUST
* use free() / rb_free() if the function returns 1
*/
static int
get_res_nt(HKEY hKey, const char *subkey, char **obuf)
{
/* Test for the size we need */
DWORD size = 0;
int result;
result = RegQueryValueEx(hKey, subkey, 0, NULL, NULL, &size);
if((result != ERROR_SUCCESS && result != ERROR_MORE_DATA) || !size)
return 0;
*obuf = rb_malloc(size + 1);
if(!*obuf)
return 0;
if(RegQueryValueEx(hKey, subkey, 0, NULL, (LPBYTE) * obuf, &size) != ERROR_SUCCESS)
{
rb_free(*obuf);
return 0;
}
if(size == 1)
{
rb_free(*obuf);
return 0;
}
return 1;
}
static int
get_res_interfaces_nt(HKEY hKey, const char *subkey, char **obuf)
{
char enumbuf[39]; /* GUIDs are 38 chars + 1 for NULL */
DWORD enum_size = 39;
int idx = 0;
HKEY hVal;
while(RegEnumKeyEx(hKey, idx++, enumbuf, &enum_size, 0,
NULL, NULL, NULL) != ERROR_NO_MORE_ITEMS)
{
int rc;
enum_size = 39;
if(RegOpenKeyEx(hKey, enumbuf, 0, KEY_QUERY_VALUE, &hVal) != ERROR_SUCCESS)
continue;
rc = get_res_nt(hVal, subkey, obuf);
RegCloseKey(hVal);
if(rc)
return 1;
}
return 0;
}
const char *
get_windows_nameservers(void)
{
/*
NameServer info via IPHLPAPI (IP helper API):
GetNetworkParams() should be the trusted source for this.
Available in Win-98/2000 and later. If that fail, fall-back to
registry information.
NameServer Registry:
On Windows 9X, the DNS server can be found in:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP\NameServer
On Windows NT/2000/XP/2003:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\NameServer
or
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\DhcpNameServer
or
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\{AdapterID}\
NameServer
or
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\{AdapterID}\
DhcpNameServer
*/
static char namelist[512];
HKEY mykey;
HKEY subkey;
DWORD data_type;
DWORD bytes;
DWORD result;
char *line = NULL;
memset(&namelist, 0, sizeof(namelist));
if(get_iphlpapi_dns_info(namelist, sizeof(namelist)) > 0)
{
return namelist;
}
if(IS_NT())
{
if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0,
KEY_READ, &mykey) == ERROR_SUCCESS)
{
RegOpenKeyEx(mykey, "Interfaces", 0,
KEY_QUERY_VALUE | KEY_ENUMERATE_SUB_KEYS, &subkey);
if(get_res_nt(mykey, NAMESERVER, &line))
{
rb_strlcpy(namelist, line, sizeof(namelist));
return namelist;
}
else if(get_res_nt(mykey, DHCPNAMESERVER, &line))
{
rb_strlcpy(namelist, line, sizeof(namelist));
rb_free(line);
}
/* Try the interfaces */
else if(get_res_interfaces_nt(subkey, NAMESERVER, &line))
{
rb_strlcpy(namelist, line, sizeof(namelist));
rb_free(line);
}
else if(get_res_interfaces_nt(subkey, DHCPNAMESERVER, &line))
{
rb_strlcpy(namelist, line, sizeof(namelist));
rb_free(line);
}
RegCloseKey(subkey);
RegCloseKey(mykey);
}
}
else
{
if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_9X, 0,
KEY_READ, &mykey) == ERROR_SUCCESS)
{
if((result = RegQueryValueEx(mykey, NAMESERVER, NULL, &data_type,
NULL, &bytes)) == ERROR_SUCCESS ||
result == ERROR_MORE_DATA)
{
if(bytes)
{
line = (char *)rb_malloc(bytes + 1);
if(RegQueryValueEx(mykey, NAMESERVER, NULL, &data_type,
(unsigned char *)line, &bytes) ==
ERROR_SUCCESS)
{
rb_strlcpy(namelist, line, sizeof(namelist));
}
free(line);
}
}
}
RegCloseKey(mykey);
}
if(strlen(namelist) > 0)
return namelist;
return NULL;
}
#endif