/*
 * Copyright 2000, International Business Machines Corporation and others.
 * All Rights Reserved.
 * 
 * This software has been released under the terms of the IBM Public
 * License.  For details, see the LICENSE file in the top-level source
 * directory or online at http://www.openafs.org/dl/license10.html
 */

#include <afs/stds.h>
#include <windows.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <malloc.h>
#include <string.h>
#include <winioctl.h>
#include <winsock2.h>
#include <nb30.h>

#include <osi.h>

#include <cm.h>
#include <cm_dir.h>
#include <cm_cell.h>
#include <cm_user.h>
#include <cm_conn.h>
#include <cm_scache.h>
#include <cm_buf.h>
#include <cm_utils.h>
#include <cm_ioctl.h>

#include <smb.h>
#include <pioctl_nt.h>

static char AFSConfigKeyName[] =
	"SYSTEM\\CurrentControlSet\\Services\\TransarcAFSDaemon\\Parameters";

#define FS_IOCTLREQUEST_MAXSIZE	8192
/* big structure for representing and storing an IOCTL request */
typedef struct fs_ioctlRequest {
	char *mp;				/* marshalling/unmarshalling ptr */
        long nbytes;				/* bytes received (when unmarshalling) */
        char data[FS_IOCTLREQUEST_MAXSIZE];	/* data we're marshalling */
} fs_ioctlRequest_t;

static int CMtoUNIXerror(int cm_code)
{
	switch (cm_code) {
		case CM_ERROR_TIMEDOUT: return ETIMEDOUT;
		case CM_ERROR_NOACCESS: return EACCES;
		case CM_ERROR_NOSUCHFILE: return ENOENT;
		case CM_ERROR_INVAL: return EINVAL;
		case CM_ERROR_BADFD: return EBADF;
		case CM_ERROR_EXISTS: return EEXIST;
		case CM_ERROR_CROSSDEVLINK: return EXDEV;
		case CM_ERROR_NOTDIR: return ENOTDIR;
		case CM_ERROR_ISDIR: return EISDIR;
		case CM_ERROR_READONLY: return EROFS;
		case CM_ERROR_WOULDBLOCK: return EWOULDBLOCK;
		case CM_ERROR_NOSUCHCELL: return ESRCH;		/* hack */
		case CM_ERROR_NOSUCHVOLUME: return EPIPE;	/* hack */
		case CM_ERROR_NOMORETOKENS: return EDOM;	/* hack */
		case CM_ERROR_TOOMANYBUFS: return EFBIG;	/* hack */
		default: return ENOTTY;
	}
}

static void InitFSRequest(fs_ioctlRequest_t *rp)
{
	rp->mp = rp->data;
        rp->nbytes = 0;
}

static long GetIoctlHandle(char *fileNamep, HANDLE *handlep)
{
	char *drivep;
	char hostName[256];
        char tbuffer[100];
	char *ctemp;
	HANDLE fh;
	HKEY parmKey;
	DWORD dummyLen;
	long code;
        int hostsize;

        if (fileNamep) {
	      drivep = strchr(fileNamep, ':');
	      if (drivep && (drivep - fileNamep) >= 1) {
		tbuffer[0] = *(drivep-1);
                tbuffer[1] = ':';
                strcpy(tbuffer+2, SMB_IOCTL_FILENAME);
	      } else
		strcpy(tbuffer, SMB_IOCTL_FILENAME);
	}
        else {
		/* No file name specified, use UNC name */
		/* First look for gateway host in Registry */
		code = RegOpenKeyEx(HKEY_LOCAL_MACHINE, AFSConfigKeyName,
					0, KEY_QUERY_VALUE, &parmKey);
		if (code != ERROR_SUCCESS)
			goto nogateway;
		dummyLen = sizeof(hostName);
		code = RegQueryValueEx(parmKey, "Gateway", NULL, NULL,
					hostName, &dummyLen);
		RegCloseKey (parmKey);
		if (code == ERROR_SUCCESS)
			goto havehost;
nogateway:
		/* No gateway name in registry; use ourself */
#ifndef AFS_WIN95_ENV
		gethostname(hostName, sizeof(hostName));
#else
                /* DJGPP version of gethostname gets the NetBIOS
                   name of the machine, so that is what we are using for
                   the AFS server name instead of the DNS name. */
                hostsize = sizeof(hostName);
                GetComputerName(hostName, &hostsize);
#endif /* AFS_WIN95_ENV */

havehost:
		ctemp = strchr(hostName, '.');	/* turn ntafs.* into ntafs */
		if (ctemp) *ctemp = 0;
		hostName[11] = 0;

		_strupr(hostName);
		sprintf(tbuffer, "\\\\%s-AFS\\all%s",
			hostName, SMB_IOCTL_FILENAME);
        }

        fflush(stdout);
	/* now open the file */
        fh = CreateFile(tbuffer, GENERIC_READ | GENERIC_WRITE,
        	FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
		OPEN_EXISTING, FILE_FLAG_WRITE_THROUGH, NULL);
        fflush(stdout);
	if (fh == INVALID_HANDLE_VALUE)
		return -1;
        
        /* return fh and success code */
        *handlep = fh;
        return 0;
}

static long Transceive(HANDLE handle, fs_ioctlRequest_t *reqp)
{
	long rcount;
        long ioCount;

        rcount = reqp->mp - reqp->data;
	if (rcount <= 0) return EINVAL;		/* not supposed to happen */
        
        if (!WriteFile(handle, reqp->data, rcount, &ioCount, NULL)) {
		/* failed to write */
                return GetLastError();
        }
        
        if (!ReadFile(handle, reqp->data, sizeof(reqp->data), &ioCount, NULL)) {
		/* failed to read */
                return GetLastError();
        }
        
        reqp->nbytes = ioCount;		/* set # of bytes available */
        reqp->mp = reqp->data;		/* restart marshalling */

	/* return success */
        return 0;
}

static long MarshallLong(fs_ioctlRequest_t *reqp, long val)
{
	memcpy(reqp->mp, &val, 4);
        reqp->mp += 4;
        return 0;
}

static long UnmarshallLong(fs_ioctlRequest_t *reqp, long *valp)
{
	/* not enough data left */
  if (reqp->nbytes < 4) { return -1; }

	memcpy(valp, reqp->mp, 4);
        reqp->mp += 4;
        reqp->nbytes -= 4;
        return 0;
}

/* includes marshalling NULL pointer as a null (0 length) string */
static long MarshallString(fs_ioctlRequest_t *reqp, char *stringp)
{
	int count;
        
	if (stringp)
	        count = strlen(stringp) + 1;	/* space required including null */
	else count = 1;

	/* watch for buffer overflow */
        if ((reqp->mp - reqp->data) + count > sizeof(reqp->data)) return -1;
        
	if (stringp) memcpy(reqp->mp, stringp, count);
	else *(reqp->mp) = 0;
        reqp->mp += count;
        return 0;
}

/* take a path with a drive letter, possibly relative, and return a full path
 * without the drive letter.  This is the full path relative to the working
 * dir for that drive letter.  The input and output paths can be the same.
 */
static long fs_GetFullPath(char *pathp, char *outPathp, long outSize)
{
	char tpath[1000];
	char origPath[1000];
        char *firstp;
        long code;
        int pathHasDrive;
        int doSwitch;
        char newPath[3];

	if (pathp[0] != 0 && pathp[1] == ':') {
		/* there's a drive letter there */
                firstp = pathp+2;
                pathHasDrive = 1;
        }
        else {
	        firstp = pathp;
		pathHasDrive = 0;
	}
        
        if (*firstp == '\\' || *firstp == '/') {
		/* already an absolute pathname, just copy it back */
                strcpy(outPathp, firstp);
                return 0;
        }
        
        GetCurrentDirectory(sizeof(origPath), origPath);
        
	doSwitch = 0;
        if (pathHasDrive && (*pathp & ~0x20) != (origPath[0] & ~0x20)) {
		/* a drive has been specified and it isn't our current drive.
                 * to get path, switch to it first.  Must case-fold drive letters
                 * for user convenience.
                 */
		doSwitch = 1;
                newPath[0] = *pathp;
                newPath[1] = ':';
                newPath[2] = 0;
                if (!SetCurrentDirectory(newPath)) {
			code = GetLastError();
                        return code;
                }
        }
        
        /* now get the absolute path to the current wdir in this drive */
        GetCurrentDirectory(sizeof(tpath), tpath);
        strcpy(outPathp, tpath+2);	/* skip drive letter */
	/* if there is a non-null name after the drive, append it */
	if (*firstp != 0) {
	        strcat(outPathp, "\\");
	        strcat(outPathp, firstp);
	}

	/* finally, if necessary, switch back to our home drive letter */
        if (doSwitch) {
		SetCurrentDirectory(origPath);
        }
        
        return 0;
}

long pioctl(char *pathp, long opcode, struct ViceIoctl *blobp, int follow)
{
	fs_ioctlRequest_t preq;
        long code;
        long temp;
        char fullPath[1000];
        HANDLE reqHandle;

	code = GetIoctlHandle(pathp, &reqHandle);
        if (code) {
	    if (pathp)
		errno = EINVAL;
	    else
		errno = ENODEV;
	    return code;
	}

	/* init the request structure */
        InitFSRequest(&preq);

	/* marshall the opcode, the path name and the input parameters */
        MarshallLong(&preq, opcode);
	/* when marshalling the path, remove the drive letter, since we already
         * used the drive letter to find the AFS daemon; we don't need it any more.
         * Eventually we'll expand relative path names here, too, since again, only
         * we understand those.
         */
	if (pathp) {
	        code = fs_GetFullPath(pathp, fullPath, sizeof(fullPath));
	        if (code) {
		    CloseHandle(reqHandle);
		    errno = EINVAL;
		    return code;
		}
	}
	else {
		strcpy(fullPath, "");
        }

        MarshallString(&preq, fullPath);
        if (blobp->in_size) {
        	memcpy(preq.mp, blobp->in, blobp->in_size);
                preq.mp += blobp->in_size;
	}
        
	/* now make the call */
        code = Transceive(reqHandle, &preq);
        if (code) {
		CloseHandle(reqHandle);
		return code;
	}
        
        /* now unmarshall the return value */
        UnmarshallLong(&preq, &temp);
        if (temp != 0) {
		CloseHandle(reqHandle);
                errno = CMtoUNIXerror(temp);
                return -1;
	}
        
        /* otherwise, unmarshall the output parameters */
        if (blobp->out_size) {
		temp = blobp->out_size;
                if (preq.nbytes < temp) temp = preq.nbytes;
                memcpy(blobp->out, preq.mp, temp);
                blobp->out_size = temp;
        }
        
	/* and return success */
	CloseHandle(reqHandle);
        return 0;
}