sess.c

Linux内核自带的cifs模块

/*
 *   fs/cifs/sess.c
 *
 *   SMB/CIFS session setup handling routines
 *
 *   Copyright (c) International Business Machines  Corp., 2006, 2007
 *   Author(s): Steve French ([e-mail])
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/fs.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "ntlmssp.h"
#include "nterr.h"
#include <linux/utsname.h>

extern void SMBNTencrypt(unsigned char *passwd, unsigned char *c8,
			 unsigned char *p24);

static __u32 cifs_ssetup_hdr(struct cifsSesInfo *ses, SESSION_SETUP_ANDX *pSMB)
{
	__u32 capabilities = 0;

	/* init fields common to all four types of SessSetup */
	/* note that header is initialized to zero in header_assemble */
	pSMB->req.AndXCommand = 0xFF;
	pSMB->req.MaxBufferSize = cpu_to_le16(ses->server->maxBuf);
	pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);

	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */

	/* BB verify whether signing required on neg or just on auth frame
	   (and NTLM case) */

	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;

	if (ses->server->secMode &
	    (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;

	if (ses->capabilities & CAP_UNICODE) {
		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
		capabilities |= CAP_UNICODE;
	}
	if (ses->capabilities & CAP_STATUS32) {
		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
		capabilities |= CAP_STATUS32;
	}
	if (ses->capabilities & CAP_DFS) {
		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
		capabilities |= CAP_DFS;
	}
	if (ses->capabilities & CAP_UNIX)
		capabilities |= CAP_UNIX;

	/* BB check whether to init vcnum BB */
	return capabilities;
}

static void unicode_ssetup_strings(char **pbcc_area, struct cifsSesInfo *ses,
				   const struct nls_table *nls_cp)
{
	char *bcc_ptr = *pbcc_area;
	int bytes_ret = 0;

	/* BB FIXME add check that strings total less
	than 335 or will need to send them as arrays */

	/* unicode strings, must be word aligned before the call */
/*	if ((long) bcc_ptr % 2)	{
		*bcc_ptr = 0;
		bcc_ptr++;
	} */
	/* copy user */
	if (ses->userName == NULL) {
		/* null user mount */
		*bcc_ptr = 0;
		*(bcc_ptr+1) = 0;
	} else { /* 300 should be long enough for any conceivable user name */
		bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->userName,
					  300, nls_cp);
	}
	bcc_ptr += 2 * bytes_ret;
	bcc_ptr += 2; /* account for null termination */
	/* copy domain */
	if (ses->domainName == NULL) {
		/* Sending null domain better than using a bogus domain name (as
		we did briefly in 2.6.18) since server will use its default */
		*bcc_ptr = 0;
		*(bcc_ptr+1) = 0;
		bytes_ret = 0;
	} else
		bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->domainName,
					  256, nls_cp);
	bcc_ptr += 2 * bytes_ret;
	bcc_ptr += 2;  /* account for null terminator */

	/* Copy OS version */
	bytes_ret = cifs_strtoUCS((__le16 *)bcc_ptr, "Linux version ", 32,
				  nls_cp);
	bcc_ptr += 2 * bytes_ret;
#if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 18)
	bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, init_utsname()->release,
				  32, nls_cp);
#else
	bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, system_utsname.release,
				  32, nls_cp);
#endif
	bcc_ptr += 2 * bytes_ret;
	bcc_ptr += 2; /* trailing null */

	bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
				  32, nls_cp);
	bcc_ptr += 2 * bytes_ret;
	bcc_ptr += 2; /* trailing null */

	*pbcc_area = bcc_ptr;
}

static void ascii_ssetup_strings(char **pbcc_area, struct cifsSesInfo *ses,
				 const struct nls_table *nls_cp)
{
	char *bcc_ptr = *pbcc_area;

	/* copy user */
	/* BB what about null user mounts - check that we do this BB */
	/* copy user */
	if (ses->userName == NULL) {
		/* BB what about null user mounts - check that we do this BB */
	} else { /* 300 should be long enough for any conceivable user name */
		strncpy(bcc_ptr, ses->userName, 300);
	}
	/* BB improve check for overflow */
	bcc_ptr += strnlen(ses->userName, 300);
	*bcc_ptr = 0;
	bcc_ptr++; /* account for null termination */

	/* copy domain */

	if (ses->domainName != NULL) {
		strncpy(bcc_ptr, ses->domainName, 256);
		bcc_ptr += strnlen(ses->domainName, 256);
	} /* else we will send a null domain name
	     so the server will default to its own domain */
	*bcc_ptr = 0;
	bcc_ptr++;

	/* BB check for overflow here */

	strcpy(bcc_ptr, "Linux version ");
	bcc_ptr += strlen("Linux version ");
#if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 18)
	strcpy(bcc_ptr, init_utsname()->release);
	bcc_ptr += strlen(init_utsname()->release) + 1;
#else
	strcpy(bcc_ptr, system_utsname.release);
	bcc_ptr += strlen(system_utsname.release) + 1;
#endif
	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;

	*pbcc_area = bcc_ptr;
}

static int decode_unicode_ssetup(char **pbcc_area, int bleft,
				 struct cifsSesInfo *ses,
				 const struct nls_table *nls_cp)
{
	int rc = 0;
	int words_left, len;
	char *data = *pbcc_area;



	cFYI(1, ("bleft %d", bleft));


	/* SMB header is unaligned, so cifs servers word align start of
	   Unicode strings */
	data++;
	bleft--; /* Windows servers do not always double null terminate
		    their final Unicode string - in which case we
		    now will not attempt to decode the byte of junk
		    which follows it */

	words_left = bleft / 2;

	/* save off server operating system */
	len = UniStrnlen((wchar_t *) data, words_left);

/* We look for obvious messed up bcc or strings in response so we do not go off
   the end since (at least) WIN2K and Windows XP have a major bug in not null
   terminating last Unicode string in response  */
	if (len >= words_left)
		return rc;

	kfree(ses->serverOS);
	/* UTF-8 string will not grow more than four times as big as UCS-16 */
	ses->serverOS = kzalloc(4 * len, GFP_KERNEL);
	if (ses->serverOS != NULL)
		cifs_strfromUCS_le(ses->serverOS, (__le16 *)data, len, nls_cp);
	data += 2 * (len + 1);
	words_left -= len + 1;

	/* save off server network operating system */
	len = UniStrnlen((wchar_t *) data, words_left);

	if (len >= words_left)
		return rc;

	kfree(ses->serverNOS);
	ses->serverNOS = kzalloc(4 * len, GFP_KERNEL); /* BB this is wrong length FIXME BB */
	if (ses->serverNOS != NULL) {
		cifs_strfromUCS_le(ses->serverNOS, (__le16 *)data, len,
				   nls_cp);
		if (strncmp(ses->serverNOS, "NT LAN Manager 4", 16) == 0) {
			cFYI(1, ("NT4 server"));
			ses->flags |= CIFS_SES_NT4;
		}
	}
	data += 2 * (len + 1);
	words_left -= len + 1;

	/* save off server domain */
	len = UniStrnlen((wchar_t *) data, words_left);

	if (len > words_left)
		return rc;

	kfree(ses->serverDomain);
	ses->serverDomain = kzalloc(2 * (len + 1), GFP_KERNEL); /* BB FIXME wrong length */
	if (ses->serverDomain != NULL) {
		cifs_strfromUCS_le(ses->serverDomain, (__le16 *)data, len,
				   nls_cp);
		ses->serverDomain[2*len] = 0;
		ses->serverDomain[(2*len) + 1] = 0;
	}
	data += 2 * (len + 1);
	words_left -= len + 1;

	cFYI(1, ("words left: %d", words_left));

	return rc;
}

static int decode_ascii_ssetup(char **pbcc_area, int bleft,
			       struct cifsSesInfo *ses,
			       const struct nls_table *nls_cp)
{
	int rc = 0;
	int len;
	char *bcc_ptr = *pbcc_area;

	cFYI(1, ("decode sessetup ascii. bleft %d", bleft));

	len = strnlen(bcc_ptr, bleft);
	if (len >= bleft)
		return rc;

	kfree(ses->serverOS);