smbw.c

来自「samba-3.0.22.tar.gz 编译smb服务器的源码」· C语言 代码 · 共 1,563 行 · 第 1/3 页

/* 
   Unix SMB/CIFS implementation.
   SMB wrapper functions
   Copyright (C) Andrew Tridgell 1998
   
   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"
#include "realcalls.h"

pstring smbw_cwd;

static struct smbw_file *smbw_files;
static struct smbw_server *smbw_srvs;

struct bitmap *smbw_file_bmap;

fstring smbw_prefix = SMBW_PREFIX;

int smbw_busy=0;

/* needs to be here because of dumb include files on some systems */
int creat_bits = O_WRONLY|O_CREAT|O_TRUNC;


/***************************************************** 
initialise structures
*******************************************************/
void smbw_init(void)
{
	extern BOOL in_client;
	static int initialised;
	char *p;
	int eno;
	pstring line;

	if (initialised) return;
	initialised = 1;

	eno = errno;

	smbw_busy++;

	DEBUGLEVEL = 0;
	setup_logging("smbsh",True);

	dbf = x_stderr;

	if ((p=smbw_getshared("LOGFILE"))) {
		dbf = sys_fopen(p, "a");
	}

	smbw_file_bmap = bitmap_allocate(SMBW_MAX_OPEN);
	if (!smbw_file_bmap) {
		exit(1);
	}

	in_client = True;

	load_interfaces();

	if ((p=smbw_getshared("SERVICESF"))) {
		pstrcpy(dyn_CONFIGFILE, p);
	}

	lp_load(dyn_CONFIGFILE,True,False,False);

	if (!init_names())
		exit(1);

	if ((p=smbw_getshared("DEBUG"))) {
		DEBUGLEVEL = atoi(p);
	}

	if ((p=smbw_getshared("RESOLVE_ORDER"))) {
		lp_set_name_resolve_order(p);
	}

	if ((p=smbw_getshared("PREFIX"))) {
		slprintf(smbw_prefix,sizeof(fstring)-1, "/%s/", p);
		all_string_sub(smbw_prefix,"//", "/", 0);
		DEBUG(2,("SMBW_PREFIX is %s\n", smbw_prefix));
	}

	slprintf(line,sizeof(line)-1,"PWD_%d", (int)getpid());
	
	p = smbw_getshared(line);
	if (!p) {
		sys_getwd(smbw_cwd);
	}
	pstrcpy(smbw_cwd, p);
	DEBUG(4,("Initial cwd is %s\n", smbw_cwd));

	smbw_busy--;

	set_maxfiles(SMBW_MAX_OPEN);

	BlockSignals(True,SIGPIPE);

	errno = eno;
}

/***************************************************** 
determine if a file descriptor is a smb one
*******************************************************/
int smbw_fd(int fd)
{
	if (smbw_busy) return 0;
	return smbw_file_bmap && bitmap_query(smbw_file_bmap, fd);
}

/***************************************************** 
determine if a file descriptor is an internal smbw fd
*******************************************************/
int smbw_local_fd(int fd)
{
	struct smbw_server *srv;
	
	smbw_init();

	if (smbw_busy) return 0;
	if (smbw_shared_fd(fd)) return 1;

	for (srv=smbw_srvs;srv;srv=srv->next) {
		if (srv->cli.fd == fd) return 1;
	}

	return 0;
}

/***************************************************** 
a crude inode number generator
*******************************************************/
ino_t smbw_inode(const char *name)
{
	if (!*name) return 2;
	return (ino_t)str_checksum(name);
}

/***************************************************** 
remove redundent stuff from a filename
*******************************************************/
void clean_fname(char *name)
{
	char *p, *p2;
	int l;
	int modified = 1;

	if (!name) return;

	while (modified) {
		modified = 0;

		DEBUG(5,("cleaning %s\n", name));

		if ((p=strstr(name,"/./"))) {
			modified = 1;
			while (*p) {
				p[0] = p[2];
				p++;
			}
		}

		if ((p=strstr(name,"//"))) {
			modified = 1;
			while (*p) {
				p[0] = p[1];
				p++;
			}
		}

		if (strcmp(name,"/../")==0) {
			modified = 1;
			name[1] = 0;
		}

		if ((p=strstr(name,"/../"))) {
			modified = 1;
			for (p2=(p>name?p-1:p);p2>name;p2--) {
				if (p2[0] == '/') break;
			}
			while (*p2) {
				p2[0] = p2[3];
				p2++;
			}
		}

		if (strcmp(name,"/..")==0) {
			modified = 1;
			name[1] = 0;
		}

		l = strlen(name);
		p = l>=3?(name+l-3):name;
		if (strcmp(p,"/..")==0) {
			modified = 1;
			for (p2=p-1;p2>name;p2--) {
				if (p2[0] == '/') break;
			}
			if (p2==name) {
				p[0] = '/';
				p[1] = 0;
			} else {
				p2[0] = 0;
			}
		}

		l = strlen(name);
		p = l>=2?(name+l-2):name;
		if (strcmp(p,"/.")==0) {
			if (p == name) {
				p[1] = 0;
			} else {
				p[0] = 0;
			}
		}

		if (strncmp(p=name,"./",2) == 0) {      
			modified = 1;
			do {
				p[0] = p[2];
			} while (*p++);
		}

		l = strlen(p=name);
		if (l > 1 && p[l-1] == '/') {
			modified = 1;
			p[l-1] = 0;
		}
	}
}



/***************************************************** 
find a workgroup (any workgroup!) that has a master 
browser on the local network
*******************************************************/
static char *smbw_find_workgroup(void)
{
	fstring server;
	char *p;
	struct in_addr *ip_list = NULL;
	int count = 0;
	int i;

	/* first off see if an existing workgroup name exists */
	p = smbw_getshared("WORKGROUP");
	if (!p) p = lp_workgroup();
	
	slprintf(server, sizeof(server), "%s#1D", p);
	if (smbw_server(server, "IPC$")) return p;

	/* go looking for workgroups */
	if (!name_resolve_bcast(MSBROWSE, 1, &ip_list, &count)) {
		DEBUG(1,("No workgroups found!"));
		return p;
	}

	for (i=0;i<count;i++) {
		static fstring name;
		if (name_status_find("*", 0, 0x1d, ip_list[i], name)) {
			slprintf(server, sizeof(server), "%s#1D", name);
			if (smbw_server(server, "IPC$")) {
				smbw_setshared("WORKGROUP", name);
				SAFE_FREE(ip_list);
				return name;
			}
		}
	}

	SAFE_FREE(ip_list);

	return p;
}

/***************************************************** 
parse a smb path into its components. 
server is one of
  1) the name of the SMB server
  2) WORKGROUP#1D for share listing
  3) WORKGROUP#__ for workgroup listing
share is the share on the server to query
path is the SMB path on the server
return the full path (ie. add cwd if needed)
*******************************************************/
char *smbw_parse_path(const char *fname, char *server, char *share, char *path)
{
	static pstring s;
	char *p;
	int len;
	fstring workgroup;

	/* add cwd if necessary */
	if (fname[0] != '/') {
		slprintf(s, sizeof(s), "%s/%s", smbw_cwd, fname);
	} else {
		pstrcpy(s, fname);
	}
	clean_fname(s);

	/* see if it has the right prefix */
	len = strlen(smbw_prefix)-1;
	if (strncmp(s,smbw_prefix,len) || 
	    (s[len] != '/' && s[len] != 0)) return s;

	/* ok, its for us. Now parse out the workgroup, share etc. */
	p = s+len;
	if (*p == '/') p++;
	if (!next_token(&p, workgroup, "/", sizeof(fstring))) {
		/* we're in /smb - give a list of workgroups */
		slprintf(server,sizeof(fstring), "%s#01", smbw_find_workgroup());
		fstrcpy(share,"IPC$");
		pstrcpy(path,"");
		return s;
	}

	if (!next_token(&p, server, "/", sizeof(fstring))) {
		/* we are in /smb/WORKGROUP */
		slprintf(server,sizeof(fstring), "%s#1D", workgroup);
		fstrcpy(share,"IPC$");
		pstrcpy(path,"");
	}

	if (!next_token(&p, share, "/", sizeof(fstring))) {
		/* we are in /smb/WORKGROUP/SERVER */
		fstrcpy(share,"IPC$");
		pstrcpy(path,"");
	}

	pstrcpy(path, p);

	all_string_sub(path, "/", "\\", 0);

	return s;
}

/***************************************************** 
determine if a path name (possibly relative) is in the 
smb name space
*******************************************************/
int smbw_path(const char *path)
{
	fstring server, share;
	pstring s;
	char *cwd;
	int len;

	if(!path)
		return 0;

	/* this is needed to prevent recursion with the BSD malloc which
	   opens /etc/malloc.conf on the first call */
	if (strncmp(path,"/etc/", 5) == 0) {
		return 0;
	}

	smbw_init();

	len = strlen(smbw_prefix)-1;

	if (path[0] == '/' && strncmp(path,smbw_prefix,len)) {
		return 0;
	}

	if (smbw_busy) return 0;

	DEBUG(3,("smbw_path(%s)\n", path));

	cwd = smbw_parse_path(path, server, share, s);

	if (strncmp(cwd,smbw_prefix,len) == 0 &&
	    (cwd[len] == '/' || cwd[len] == 0)) {
		return 1;
	}

	return 0;
}

/***************************************************** 
return a unix errno from a SMB error pair
*******************************************************/
int smbw_errno(struct cli_state *c)
{
	return cli_errno(c);
}

/* Return a username and password given a server and share name */

void get_envvar_auth_data(char *server, char *share, char **workgroup,
			  char **username, char **password)
{
	/* Fall back to shared memory/environment variables */

	*username = smbw_getshared("USER");
	if (!*username) *username = getenv("USER");
	if (!*username) *username = "guest";

	*workgroup = smbw_getshared("WORKGROUP");
	if (!*workgroup) *workgroup = lp_workgroup();

	*password = smbw_getshared("PASSWORD");
	if (!*password) *password = "";
}

static smbw_get_auth_data_fn get_auth_data_fn = get_envvar_auth_data;

/*****************************************************
set the get auth data function
******************************************************/
void smbw_set_auth_data_fn(smbw_get_auth_data_fn fn)
{
	get_auth_data_fn = fn;
}

/***************************************************** 
return a connection to a server (existing or new)
*******************************************************/
struct smbw_server *smbw_server(char *server, char *share)
{
	struct smbw_server *srv=NULL;
	struct cli_state c;
	char *username;
	char *password;
	char *workgroup;
	struct nmb_name called, calling;
	char *p, *server_n = server;
	fstring group;
	pstring ipenv;
	struct in_addr ip;

        zero_ip(&ip);
	ZERO_STRUCT(c);

	get_auth_data_fn(server, share, &workgroup, &username, &password);

	/* try to use an existing connection */
	for (srv=smbw_srvs;srv;srv=srv->next) {
		if (strcmp(server,srv->server_name)==0 &&
		    strcmp(share,srv->share_name)==0 &&
		    strcmp(workgroup,srv->workgroup)==0 &&
		    strcmp(username, srv->username) == 0) 
			return srv;
	}

	if (server[0] == 0) {
		errno = EPERM;
		return NULL;
	}

	make_nmb_name(&calling, global_myname(), 0x0);
	make_nmb_name(&called , server, 0x20);

	DEBUG(4,("server_n=[%s] server=[%s]\n", server_n, server));

	if ((p=strchr_m(server_n,'#')) && 
	    (strcmp(p+1,"1D")==0 || strcmp(p+1,"01")==0)) {
		struct in_addr sip;
		pstring s;

		fstrcpy(group, server_n);
		p = strchr_m(group,'#');
		*p = 0;
		
		/* cache the workgroup master lookup */
		slprintf(s,sizeof(s)-1,"MASTER_%s", group);
		if (!(server_n = smbw_getshared(s))) {
			if (!find_master_ip(group, &sip)) {
				errno = ENOENT;
				return NULL;
			}
			fstrcpy(group, inet_ntoa(sip));
			server_n = group;
			smbw_setshared(s,server_n);
		}
	}

	DEBUG(4,(" -> server_n=[%s] server=[%s]\n", server_n, server));

 again:
	slprintf(ipenv,sizeof(ipenv)-1,"HOST_%s", server_n);

        zero_ip(&ip);
	if ((p=smbw_getshared(ipenv))) {
		ip = *(interpret_addr2(p));
	}

	/* have to open a new connection */
	if (!cli_initialise(&c) || !cli_connect(&c, server_n, &ip)) {
		errno = ENOENT;
		return NULL;
	}

	if (!cli_session_request(&c, &calling, &called)) {
		cli_shutdown(&c);
		if (strcmp(called.name, "*SMBSERVER")) {
			make_nmb_name(&called , "*SMBSERVER", 0x20);
			goto again;
		}
		errno = ENOENT;
		return NULL;
	}

	DEBUG(4,(" session request ok\n"));

	if (!cli_negprot(&c)) {
		cli_shutdown(&c);
		errno = ENOENT;