substitute.c

samba-3.0.22.tar.gz 编译smb服务器的源码

/* 
   Unix SMB/CIFS implementation.
   string substitution functions
   Copyright (C) Andrew Tridgell 1992-2000
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program 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 General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/


#include "includes.h"

extern struct current_user current_user;

fstring local_machine="";
fstring remote_arch="UNKNOWN";
userdom_struct current_user_info;
fstring remote_proto="UNKNOWN";

static fstring remote_machine;
static fstring smb_user_name;

/** 
 * Set the 'local' machine name
 * @param local_name the name we are being called
 * @param if this is the 'final' name for us, not be be changed again
 */

void set_local_machine_name(const char* local_name, BOOL perm)
{
	static BOOL already_perm = False;
	fstring tmp_local_machine;

	fstrcpy(tmp_local_machine,local_name);
	trim_char(tmp_local_machine,' ',' ');

	/*
	 * Windows NT/2k uses "*SMBSERVER" and XP uses "*SMBSERV"
	 * arrggg!!! 
	 */

	if ( strequal(tmp_local_machine, "*SMBSERVER") || strequal(tmp_local_machine, "*SMBSERV") )  {
		fstrcpy( local_machine, client_socket_addr() );
		return;
	}

	if (already_perm)
		return;

	already_perm = perm;

	alpha_strcpy(local_machine,tmp_local_machine,SAFE_NETBIOS_CHARS,sizeof(local_machine)-1);
	strlower_m(local_machine);
}

/** 
 * Set the 'remote' machine name
 * @param remote_name the name our client wants to be called by
 * @param if this is the 'final' name for them, not be be changed again
 */

void set_remote_machine_name(const char* remote_name, BOOL perm)
{
	static BOOL already_perm = False;
	fstring tmp_remote_machine;

	if (already_perm)
		return;

	already_perm = perm;

	fstrcpy(tmp_remote_machine,remote_name);
	trim_char(tmp_remote_machine,' ',' ');
	alpha_strcpy(remote_machine,tmp_remote_machine,SAFE_NETBIOS_CHARS,sizeof(remote_machine)-1);
	strlower_m(remote_machine);
}

const char* get_remote_machine_name(void) 
{
	return remote_machine;
}

const char* get_local_machine_name(void) 
{
	if (!*local_machine) {
		return global_myname();
	}

	return local_machine;
}

/*******************************************************************
 Setup the string used by %U substitution.
********************************************************************/

void sub_set_smb_name(const char *name)
{
	fstring tmp;
	int len;
	BOOL is_machine_account = False;

	/* don't let anonymous logins override the name */
	if (! *name)
		return;


	fstrcpy( tmp, name );
	trim_char( tmp, ' ', ' ' );
	strlower_m( tmp );

	len = strlen( tmp );

	if ( len == 0 )
		return;

	/* long story but here goes....we have to allow usernames
	   ending in '$' as they are valid machine account names.
	   So check for a machine account and re-add the '$'
	   at the end after the call to alpha_strcpy().   --jerry  */
	   
	if ( tmp[len-1] == '$' )
		is_machine_account = True;
	
	alpha_strcpy( smb_user_name, tmp, SAFE_NETBIOS_CHARS, sizeof(smb_user_name)-1 );

	if ( is_machine_account ) {
		len = strlen( smb_user_name );
		smb_user_name[len-1] = '$';
	}
}

char* sub_get_smb_name( void )
{
	return smb_user_name;
}

/*******************************************************************
 Setup the strings used by substitutions. Called per packet. Ensure
 %U name is set correctly also.
********************************************************************/

void set_current_user_info(const userdom_struct *pcui)
{
	current_user_info = *pcui;
	/* The following is safe as current_user_info.smb_name
	 * has already been sanitised in register_vuid. */
	fstrcpy(smb_user_name, current_user_info.smb_name);
}

/*******************************************************************
 return the current active user name
*******************************************************************/

const char* get_current_username( void )
{
	if ( current_user_info.smb_name[0] == '\0' )
		return smb_user_name;

	return current_user_info.smb_name; 
}

/*******************************************************************
 Given a pointer to a %$(NAME) expand it as an environment variable.
 Return the number of characters by which the pointer should be advanced.
 Based on code by Branko Cibej <[e-mail]>
 When this is called p points at the '%' character.
********************************************************************/

static size_t expand_env_var(char *p, int len)
{
	fstring envname;
	char *envval;
	char *q, *r;
	int copylen;

	if (p[1] != '$')
		return 1;

	if (p[2] != '(')
		return 2;

	/*
	 * Look for the terminating ')'.
	 */

	if ((q = strchr_m(p,')')) == NULL) {
		DEBUG(0,("expand_env_var: Unterminated environment variable [%s]\n", p));
		return 2;
	}

	/*
	 * Extract the name from within the %$(NAME) string.
	 */

	r = p+3;
	copylen = MIN((q-r),(sizeof(envname)-1));
	strncpy(envname,r,copylen);
	envname[copylen] = '\0';

	if ((envval = getenv(envname)) == NULL) {
		DEBUG(0,("expand_env_var: Environment variable [%s] not set\n", envname));
		return 2;
	}

	/*
	 * Copy the full %$(NAME) into envname so it
	 * can be replaced.
	 */

	copylen = MIN((q+1-p),(sizeof(envname)-1));
	strncpy(envname,p,copylen);
	envname[copylen] = '\0';
	string_sub(p,envname,envval,len);
	return 0; /* Allow the environment contents to be parsed. */
}

/*******************************************************************
 Given a pointer to a %$(NAME) in p and the whole string in str
 expand it as an environment variable.
 Return a new allocated and expanded string.
 Based on code by Branko Cibej <[e-mail]>
 When this is called p points at the '%' character.
 May substitute multiple occurrencies of the same env var.
********************************************************************/


static char * realloc_expand_env_var(char *str, char *p)
{
	char *envname;
	char *envval;
	char *q, *r;
	int copylen;

	if (p[0] != '%' || p[1] != '$' || p[2] != '(')
		return str;

	/*
	 * Look for the terminating ')'.
	 */

	if ((q = strchr_m(p,')')) == NULL) {
		DEBUG(0,("expand_env_var: Unterminated environment variable [%s]\n", p));
		return str;
	}

	/*
	 * Extract the name from within the %$(NAME) string.
	 */

	r = p + 3;
	copylen = q - r;
	envname = (char *)SMB_MALLOC(copylen + 1 + 4); /* reserve space for use later add %$() chars */
	if (envname == NULL) return NULL;
	strncpy(envname,r,copylen);
	envname[copylen] = '\0';

	if ((envval = getenv(envname)) == NULL) {
		DEBUG(0,("expand_env_var: Environment variable [%s] not set\n", envname));
		SAFE_FREE(envname);
		return str;
	}

	/*
	 * Copy the full %$(NAME) into envname so it
	 * can be replaced.
	 */

	copylen = q + 1 - p;
	strncpy(envname,p,copylen);
	envname[copylen] = '\0';
	r = realloc_string_sub(str, envname, envval);
	SAFE_FREE(envname);
	if (r == NULL) return NULL;
	return r;
}

/*******************************************************************
 Patch from [e-mail]
 Added this to implement %p (NIS auto-map version of %H)
*******************************************************************/

static char *automount_path(const char *user_name)
{
	static pstring server_path;

	/* use the passwd entry as the default */
	/* this will be the default if WITH_AUTOMOUNT is not used or fails */

	pstrcpy(server_path, get_user_home_dir(user_name));

#if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))

	if (lp_nis_home_map()) {
		const char *home_path_start;
		const char *automount_value = automount_lookup(user_name);

		if(strlen(automount_value) > 0) {
			home_path_start = strchr_m(automount_value,':');
			if (home_path_start != NULL) {
				DEBUG(5, ("NIS lookup succeeded.  Home path is: %s\n",
						home_path_start?(home_path_start+1):""));
				pstrcpy(server_path, home_path_start+1);
			}
		} else {
			/* NIS key lookup failed: default to user home directory from password file */
			DEBUG(5, ("NIS lookup failed. Using Home path from passwd file. Home path is: %s\n", server_path ));
		}
	}
#endif

	DEBUG(4,("Home server path: %s\n", server_path));

	return server_path;
}

/*******************************************************************
 Patch from [e-mail]
 This is Luke's original function with the NIS lookup code
 moved out to a separate function.
*******************************************************************/

static const char *automount_server(const char *user_name)
{
	static pstring server_name;
	const char *local_machine_name = get_local_machine_name(); 

	/* use the local machine name as the default */
	/* this will be the default if WITH_AUTOMOUNT is not used or fails */
	if (local_machine_name && *local_machine_name)
		pstrcpy(server_name, local_machine_name);
	else
		pstrcpy(server_name, global_myname());
	
#if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))

	if (lp_nis_home_map()) {
	        int home_server_len;
		char *automount_value = automount_lookup(user_name);
		home_server_len = strcspn(automount_value,":");
		DEBUG(5, ("NIS lookup succeeded.  Home server length: %d\n",home_server_len));
		if (home_server_len > sizeof(pstring))
			home_server_len = sizeof(pstring);
		strncpy(server_name, automount_value, home_server_len);
                server_name[home_server_len] = '\0';
	}
#endif

	DEBUG(4,("Home server: %s\n", server_name));

	return server_name;
}

/****************************************************************************
 Do some standard substitutions in a string.
 len is the length in bytes of the space allowed in string str. If zero means
 don't allow expansions.
****************************************************************************/

void standard_sub_basic(const char *smb_name, char *str,size_t len)
{
	char *p, *s;
	fstring pidstr;
	struct passwd *pass;
	const char *local_machine_name = get_local_machine_name();

	for (s=str; (p=strchr_m(s, '%'));s=p) {
		fstring tmp_str;

		int l = (int)len - (int)(p-str);

		if (l < 0)
			l = 0;
		
		switch (*(p+1)) {
		case 'U' : 
			fstrcpy(tmp_str, smb_name);
			strlower_m(tmp_str);
			string_sub(p,"%U",tmp_str,l);
			break;
		case 'G' :
			fstrcpy(tmp_str, smb_name);
			if ((pass = Get_Pwnam(tmp_str))!=NULL) {
				string_sub(p,"%G",gidtoname(pass->pw_gid),l);
			} else {
				p += 2;
			}
			break;
		case 'D' :
			fstrcpy(tmp_str, current_user_info.domain);
			strupper_m(tmp_str);
			string_sub(p,"%D", tmp_str,l);
			break;
		case 'I' :
			string_sub(p,"%I", client_addr(),l);
			break;
		case 'i' :
			string_sub(p,"%i", client_socket_addr(),l);
			break;
		case 'L' :
			if (!StrnCaseCmp(p, "%LOGONSERVER%", strlen("%LOGONSERVER%"))) {
				p++;
				break;
			}

			if (local_machine_name && *local_machine_name) {
				string_sub_once(p, "%L", local_machine_name, l); 
			} else {
				pstring temp_name;

				pstrcpy(temp_name, global_myname());
				strlower_m(temp_name);
				string_sub_once(p, "%L", temp_name, l); 
			}
			break;
		case 'M' :