path: root/source4/lib/util.c

/* 
   Unix SMB/CIFS implementation.
   Samba utility functions
   Copyright (C) Andrew Tridgell 1992-1998
   Copyright (C) Jeremy Allison 2001-2002
   Copyright (C) Simo Sorce 2001
   Copyright (C) Jim McDonough (jmcd@us.ibm.com)  2003.
   Copyright (C) James J Myers 2003
   
   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"

/**************************************************************************n
 Find a suitable temporary directory. The result should be copied immediately
 as it may be overwritten by a subsequent call.
****************************************************************************/

const char *tmpdir(void)
{
	char *p;
	if ((p = getenv("TMPDIR")))
		return p;
	return "/tmp";
}

/****************************************************************************
 Determine whether we are in the specified group.
****************************************************************************/

BOOL in_group(gid_t group, gid_t current_gid, int ngroups, const gid_t *groups)
{
	int i;

	if (group == current_gid)
		return(True);

	for (i=0;i<ngroups;i++)
		if (group == groups[i])
			return(True);

	return(False);
}

/*******************************************************************
 Check if a file exists - call vfs_file_exist for samba files.
********************************************************************/

BOOL file_exist(const char *fname,SMB_STRUCT_STAT *sbuf)
{
	SMB_STRUCT_STAT st;
	if (!sbuf)
		sbuf = &st;
  
	if (sys_stat(fname,sbuf) != 0) 
		return(False);

	return((S_ISREG(sbuf->st_mode)) || (S_ISFIFO(sbuf->st_mode)));
}

/*******************************************************************
 Check a files mod time.
********************************************************************/

time_t file_modtime(const char *fname)
{
	SMB_STRUCT_STAT st;
  
	if (sys_stat(fname,&st) != 0) 
		return(0);

	return(st.st_mtime);
}

/*******************************************************************
 Check if a directory exists.
********************************************************************/

BOOL directory_exist(const char *dname,SMB_STRUCT_STAT *st)
{
	SMB_STRUCT_STAT st2;
	BOOL ret;

	if (!st)
		st = &st2;

	if (sys_stat(dname,st) != 0) 
		return(False);

	ret = S_ISDIR(st->st_mode);
	if(!ret)
		errno = ENOTDIR;
	return ret;
}

/*******************************************************************
 Returns the size in bytes of the named file.
********************************************************************/
SMB_OFF_T get_file_size(char *file_name)
{
	SMB_STRUCT_STAT buf;
	buf.st_size = 0;
	if(sys_stat(file_name,&buf) != 0)
		return (SMB_OFF_T)-1;
	return(buf.st_size);
}

/*******************************************************************
 Close the low 3 fd's and open dev/null in their place.
********************************************************************/
void close_low_fds(BOOL stderr_too)
{
#ifndef VALGRIND
	int fd;
	int i;

	close(0);
	close(1); 

	if (stderr_too)
		close(2);

	/* try and use up these file descriptors, so silly
		library routines writing to stdout etc won't cause havoc */
	for (i=0;i<3;i++) {
		if (i == 2 && !stderr_too)
			continue;

		fd = sys_open("/dev/null",O_RDWR,0);
		if (fd < 0)
			fd = sys_open("/dev/null",O_WRONLY,0);
		if (fd < 0) {
			DEBUG(0,("Can't open /dev/null\n"));
			return;
		}
		if (fd != i) {
			DEBUG(0,("Didn't get file descriptor %d\n",i));
			return;
		}
	}
#endif
}

/****************************************************************************
 Set a fd into blocking/nonblocking mode. Uses POSIX O_NONBLOCK if available,
 else
  if SYSV use O_NDELAY
  if BSD use FNDELAY
****************************************************************************/

int set_blocking(int fd, BOOL set)
{
	int val;
#ifdef O_NONBLOCK
#define FLAG_TO_SET O_NONBLOCK
#else
#ifdef SYSV
#define FLAG_TO_SET O_NDELAY
#else /* BSD */
#define FLAG_TO_SET FNDELAY
#endif
#endif

	if((val = sys_fcntl_long(fd, F_GETFL, 0)) == -1)
		return -1;
	if(set) /* Turn blocking on - ie. clear nonblock flag */
		val &= ~FLAG_TO_SET;
	else
		val |= FLAG_TO_SET;
	return sys_fcntl_long( fd, F_SETFL, val);
#undef FLAG_TO_SET
}


/*******************************************************************
 Sleep for a specified number of milliseconds.
********************************************************************/

void msleep(uint_t t)
{
	struct timeval tval;  

	tval.tv_sec = t/1000;
	tval.tv_usec = 1000*(t%1000);
	/* this should be the real select - do NOT replace
	   with sys_select() */
	select(0,NULL,NULL,NULL,&tval);
}

/****************************************************************************
 Become a daemon, discarding the controlling terminal.
****************************************************************************/

void become_daemon(BOOL Fork)
{
	if (Fork) {
		if (fork()) {
			_exit(0);
		}
	}

  /* detach from the terminal */
#ifdef HAVE_SETSID
	setsid();
#elif defined(TIOCNOTTY)
	{
		int i = sys_open("/dev/tty", O_RDWR, 0);
		if (i != -1) {
			ioctl(i, (int) TIOCNOTTY, (char *)0);      
			close(i);
		}
	}
#endif /* HAVE_SETSID */

	/* Close fd's 0,1,2. Needed if started by rsh */
	close_low_fds(False);  /* Don't close stderr, let the debug system
				  attach it to the logfile */
}


/****************************************************************************
 Expand a pointer to be a particular size.
****************************************************************************/

void *Realloc(void *p,size_t size)
{
	void *ret=NULL;

	if (size == 0) {
		SAFE_FREE(p);
		DEBUG(5,("Realloc asked for 0 bytes\n"));
		return NULL;
	}

	if (!p)
		ret = (void *)malloc(size);
	else
		ret = (void *)realloc(p,size);

	if (!ret)
		DEBUG(0,("Memory allocation error: failed to expand to %d bytes\n",(int)size));

	return(ret);
}

/****************************************************************************
 Free memory, checks for NULL.
 Use directly SAFE_FREE()
 Exists only because we need to pass a function pointer somewhere --SSS
****************************************************************************/

void safe_free(void *p)
{
	SAFE_FREE(p);
}


/*
  see if a string matches either our primary or one of our secondary 
  netbios aliases. do a case insensitive match
*/
BOOL is_myname(const char *name)
{
	const char **aliases;
	int i;

	if (strcasecmp(name, lp_netbios_name()) == 0) {
		return True;
	}

	aliases = lp_netbios_aliases();
	for (i=0; aliases && aliases[i]; i++) {
		if (strcasecmp(name, aliases[i]) == 0) {
			return True;
		}
	}

	return False;
}


/****************************************************************************
 Get my own name, return in malloc'ed storage.
****************************************************************************/

char* get_myname(void)
{
	char *hostname;
	const int host_name_max = 255;
	char *p;

	hostname = malloc(host_name_max+1);
	*hostname = 0;

	/* get my host name */
	if (gethostname(hostname, host_name_max+1) == -1) {
		DEBUG(0,("gethostname failed\n"));
		return NULL;
	} 

	/* Ensure null termination. */
	hostname[host_name_max] = '\0';

	/* split off any parts after an initial . */
	p = strchr_m(hostname,'.');

	if (p)
		*p = 0;
	
	return hostname;
}

/****************************************************************************
 Get my own name, including domain.
****************************************************************************/

BOOL get_myfullname(char *my_name)
{
	pstring hostname;

	*hostname = 0;

	/* get my host name */
	if (gethostname(hostname, sizeof(hostname)) == -1) {
		DEBUG(0,("gethostname failed\n"));
		return False;
	} 

	/* Ensure null termination. */
	hostname[sizeof(hostname)-1] = '\0';

	if (my_name)
		fstrcpy(my_name, hostname);
	return True;
}

/****************************************************************************
 Get my own domain name.
****************************************************************************/

BOOL get_mydomname(fstring my_domname)
{
	pstring hostname;
	char *p;

	*hostname = 0;
	/* get my host name */
	if (gethostname(hostname, sizeof(hostname)) == -1) {
		DEBUG(0,("gethostname failed\n"));
		return False;
	} 

	/* Ensure null termination. */
	hostname[sizeof(hostname)-1] = '\0';

	p = strchr_m(hostname, '.');

	if (!p)
		return False;

	p++;
	
	if (my_domname)
		fstrcpy(my_domname, p);

	return True;
}

/****************************************************************************
 Interpret a protocol description string, with a default.
****************************************************************************/

int interpret_protocol(char *str,int def)
{
	if (strequal(str,"NT1"))
		return(PROTOCOL_NT1);
	if (strequal(str,"LANMAN2"))
		return(PROTOCOL_LANMAN2);
	if (strequal(str,"LANMAN1"))
		return(PROTOCOL_LANMAN1);
	if (strequal(str,"CORE"))
		return(PROTOCOL_CORE);
	if (strequal(str,"COREPLUS"))
		return(PROTOCOL_COREPLUS);
	if (strequal(str,"CORE+"))
		return(PROTOCOL_COREPLUS);
  
	DEBUG(0,("Unrecognised protocol level %s\n",str));
  
	return(def);
}

/****************************************************************************
 Return true if a string could be a pure IP address.
****************************************************************************/

BOOL is_ipaddress(const char *str)
{
	BOOL pure_address = True;
	int i;
  
	for (i=0; pure_address && str[i]; i++)
		if (!(isdigit((int)str[i]) || str[i] == '.'))
			pure_address = False;

	/* Check that a pure number is not misinterpreted as an IP */
	pure_address = pure_address && (strchr_m(str, '.') != NULL);

	return pure_address;
}

/****************************************************************************
 Interpret an internet address or name into an IP address in 4 byte form.
****************************************************************************/

uint32_t interpret_addr(const char *str)
{
	struct hostent *hp;
	uint32_t res;

	if (strcmp(str,"0.0.0.0") == 0)
		return(0);
	if (strcmp(str,"255.255.255.255") == 0)
		return(0xFFFFFFFF);

	/* if it's in the form of an IP address then get the lib to interpret it */
	if (is_ipaddress(str)) {
		res = inet_addr(str);
	} else {
		/* otherwise assume it's a network name of some sort and use 
			sys_gethostbyname */
		if ((hp = sys_gethostbyname(str)) == 0) {
			DEBUG(3,("sys_gethostbyname: Unknown host. %s\n",str));
			return 0;
		}

		if(hp->h_addr == NULL) {
			DEBUG(3,("sys_gethostbyname: host address is invalid for host %s\n",str));
			return 0;
		}
		putip((char *)&res,(char *)hp->h_addr);
	}

	if (res == (uint32_t)-1)
		return(0);

	return(res);
}

/*******************************************************************
 A convenient addition to interpret_addr().
******************************************************************/

struct in_addr *interpret_addr2(TALLOC_CTX *mem_ctx, const char *str)
{
	struct in_addr *ret;
	uint32_t a = interpret_addr(str);
	
	ret = talloc(mem_ctx, sizeof(struct in_addr));
	if (!ret) return NULL;
	ret->s_addr = a;
	return(ret);
}

/*******************************************************************
 Check if an IP is the 0.0.0.0.
******************************************************************/

BOOL is_zero_ip(struct in_addr ip)
{
	uint32_t a;
	putip((char *)&a,(char *)&ip);
	return(a == 0);
}

/*******************************************************************
 Set an IP to 0.0.0.0.
******************************************************************/

void zero_ip(struct in_addr *ip)
{
	*ip = inet_makeaddr(0,0);
	return;
}


/*******************************************************************
 Are two IPs on the same subnet?
********************************************************************/

BOOL same_net(struct in_addr ip1,struct in_addr ip2,struct in_addr mask)
{
	uint32_t net1,net2,nmask;

	nmask = ntohl(mask.s_addr);
	net1  = ntohl(ip1.s_addr);
	net2  = ntohl(ip2.s_addr);
            
	return((net1 & nmask) == (net2 & nmask));
}


/****************************************************************************
 Check if a process exists. Does this work on all unixes?
****************************************************************************/

BOOL process_exists(pid_t pid)
{
	/* Doing kill with a non-positive pid causes messages to be
	 * sent to places we don't want. */
	SMB_ASSERT(pid > 0);
	return(kill(pid,0) == 0 || errno != ESRCH);
}

/****************************************************************************
 Simple routine to do POSIX file locking. Cruft in NFS and 64->32 bit mapping
 is dealt with in posix.c
****************************************************************************/

BOOL fcntl_lock(int fd, int op, SMB_OFF_T offset, SMB_OFF_T count, int type)
{
	SMB_STRUCT_FLOCK lock;
	int ret;

	DEBUG(8,("fcntl_lock %d %d %.0f %.0f %d\n",fd,op,(double)offset,(double)count,type));

	lock.l_type = type;
	lock.l_whence = SEEK_SET;
	lock.l_start = offset;
	lock.l_len = count;
	lock.l_pid = 0;

	ret = sys_fcntl_ptr(fd,op,&lock);

	if (ret == -1 && errno != 0)
		DEBUG(3,("fcntl_lock: fcntl lock gave errno %d (%s)\n",errno,strerror(errno)));

	/* a lock query */
	if (op == SMB_F_GETLK) {
		if ((ret != -1) &&
				(lock.l_type != F_UNLCK) && 
				(lock.l_pid != 0) && 
				(lock.l_pid != getpid())) {
			DEBUG(3,("fcntl_lock: fd %d is locked by pid %d\n",fd,(int)lock.l_pid));
			return(True);
		}

		/* it must be not locked or locked by me */
		return(False);
	}

	/* a lock set or unset */
	if (ret == -1) {
		DEBUG(3,("fcntl_lock: lock failed at offset %.0f count %.0f op %d type %d (%s)\n",
			(double)offset,(double)count,op,type,strerror(errno)));
		return(False);
	}

	/* everything went OK */
	DEBUG(8,("fcntl_lock: Lock call successful\n"));

	return(True);
}

/*******************************************************************
 Set the remote_arch string based on an enum. This is used in places
where we desperately need to distinguish client type. 
********************************************************************/
void set_remote_arch(struct smbsrv_connection *smb, enum remote_arch_types type)
{
	const char *arch;

	smb->negotiate.ra_type = type;
	switch (type) {
	case RA_WFWG:
		arch = "WfWg";
		return;
	case RA_OS2:
		arch = "OS2";
		return;
	case RA_WIN95:
		arch = "Win95";
		return;
	case RA_WINNT:
		arch = "WinNT";
		return;
	case RA_WIN2K:
		arch = "Win2K";
		return;
	case RA_WINXP:
		arch = "WinXP";
		return;
	case RA_SAMBA:
		arch = "Samba";
		return;
	default:
		smb->negotiate.ra_type = RA_UNKNOWN;
		arch = "UNKNOWN";
		break;
	}

	sub_set_remote_arch(arch);
}


static void print_asc(int level, const uint8_t *buf,int len)
{
	int i;
	for (i=0;i<len;i++)
		DEBUGADD(level,("%c", isprint(buf[i])?buf[i]:'.'));
}

void dump_data(int level, const char *buf1,int len)
{
	const uint8_t *buf = (const uint8_t *)buf1;
	int i=0;
	if (len<=0) return;

	if (!DEBUGLVL(level)) return;
	
	DEBUGADD(level,("[%03X] ",i));
	for (i=0;i<len;) {
		DEBUGADD(level,("%02X ",(int)buf[i]));
		i++;
		if (i%8 == 0) DEBUGADD(level,(" "));
		if (i%16 == 0) {      
			print_asc(level,&buf[i-16],8); DEBUGADD(level,(" "));
			print_asc(level,&buf[i-8],8); DEBUGADD(level,("\n"));
			if (i<len) DEBUGADD(level,("[%03X] ",i));
		}
	}
	if (i%16) {
		int n;
		n = 16 - (i%16);
		DEBUGADD(level,(" "));
		if (n>8) DEBUGADD(level,(" "));
		while (n--) DEBUGADD(level,("   "));
		n = MIN(8,i%16);
		print_asc(level,&buf[i-(i%16)],n); DEBUGADD(level,( " " ));
		n = (i%16) - n;
		if (n>0) print_asc(level,&buf[i-n],n); 
		DEBUGADD(level,("\n"));    
	}	
}

/*****************************************************************
 Possibly replace mkstemp if it is broken.
*****************************************************************/  

int smb_mkstemp(char *template)
{
#if HAVE_SECURE_MKSTEMP
	return mkstemp(template);
#else
	/* have a reasonable go at emulating it. Hope that
	   the system mktemp() isn't completly hopeless */
	char *p = mktemp(template);
	if (!p)
		return -1;
	return open(p, O_CREAT|O_EXCL|O_RDWR, 0600);
#endif
}

/*****************************************************************
 malloc that aborts with smb_panic on fail or zero size.
 *****************************************************************/  

void *smb_xmalloc(size_t size)
{
	void *p;
	if (size == 0)
		smb_panic("smb_xmalloc: called with zero size.\n");
	if ((p = malloc(size)) == NULL)
		smb_panic("smb_xmalloc: malloc fail.\n");
	return p;
}

/**
 Memdup with smb_panic on fail.
**/

void *smb_xmemdup(const void *p, size_t size)
{
	void *p2;
	p2 = smb_xmalloc(size);
	memcpy(p2, p, size);
	return p2;
}

/**
 strdup that aborts on malloc fail.
**/

char *smb_xstrdup(const char *s)
{
	char *s1 = strdup(s);
	if (!s1)
		smb_panic("smb_xstrdup: malloc fail\n");
	return s1;
}


/*****************************************************************
 Like strdup but for memory.
*****************************************************************/  

void *memdup(const void *p, size_t size)
{
	void *p2;
	if (size == 0)
		return NULL;
	p2 = malloc(size);
	if (!p2)
		return NULL;
	memcpy(p2, p, size);
	return p2;
}

/*****************************************************************
 Get local hostname and cache result.
*****************************************************************/  

char *myhostname(TALLOC_CTX *mem_ctx)
{
	char *myname, *ret;
	myname = get_myname();
	ret = talloc_strdup(mem_ctx, myname);
	free(myname);
	return ret;

}

/**********************************************************************
 Converts a name to a fully qalified domain name.
***********************************************************************/

char *name_to_fqdn(TALLOC_CTX *mem_ctx, const char *name)
{
	struct hostent *hp = sys_gethostbyname(name);
	if ( hp && hp->h_name && *hp->h_name ) {
		DEBUG(10,("name_to_fqdn: lookup for %s -> %s.\n", name, hp->h_name));
		return talloc_strdup(mem_ctx, hp->h_name);
	} else {
		DEBUG(10,("name_to_fqdn: lookup for %s failed.\n", name));
		return talloc_strdup(mem_ctx, name);
	}
}


/*****************************************************************
 A useful function for returning a path in the Samba lock directory.
*****************************************************************/  

char *lock_path(TALLOC_CTX* mem_ctx, const char *name)
{
	char *fname;

	fname = talloc_strdup(mem_ctx, lp_lockdir());
	trim_string(fname,"","/");
	
	if (!directory_exist(fname,NULL))
		mkdir(fname,0755);
	
	fname = talloc_asprintf(mem_ctx, "%s/%s", fname, name);

	return fname;
}

/**
 * @brief Returns an absolute path to a file in the Samba lib directory.
 *
 * @param name File to find, relative to LIBDIR.
 *
 * @retval Pointer to a talloc'ed string containing the full path.
 **/

char *lib_path(TALLOC_CTX* mem_ctx, const char *name)
{
	char *fname;
	fname = talloc_asprintf(mem_ctx, "%s/%s", dyn_LIBDIR, name);
	return fname;
}

/**
 * @brief Returns the platform specific shared library extension.
 *
 * @retval Pointer to a static #fstring containing the extension.
 **/

const char *shlib_ext(void)
{
  return dyn_SHLIBEXT;
}


/*********************************************************
 Recursive routine that is called by unix_wild_match.
*********************************************************/

static BOOL unix_do_match(char *regexp, char *str)
{
	char *p;

	for( p = regexp; *p && *str; ) {

		switch(*p) {
			case '?':
				str++;
				p++;
				break;

			case '*':

				/*
				 * Look for a character matching 
				 * the one after the '*'.
				 */
				p++;
				if(!*p)
					return True; /* Automatic match */
				while(*str) {

					while(*str && (*p != *str))
						str++;

					/*
					 * Patch from weidel@multichart.de. In the case of the regexp
					 * '*XX*' we want to ensure there are at least 2 'X' characters
					 * in the string after the '*' for a match to be made.
					 */

					{
						int matchcount=0;

						/*
						 * Eat all the characters that match, but count how many there were.
						 */

						while(*str && (*p == *str)) {
							str++;
							matchcount++;
						}

						/*
						 * Now check that if the regexp had n identical characters that
						 * matchcount had at least that many matches.
						 */

						while ( *(p+1) && (*(p+1) == *p)) {
							p++;
							matchcount--;
						}

						if ( matchcount <= 0 )
							return False;
					}

					str--; /* We've eaten the match char after the '*' */

					if(unix_do_match(p, str))
						return True;

					if(!*str)
						return False;
					else
						str++;
				}
				return False;

			default:
				if(*str != *p)
					return False;
				str++;
				p++;
				break;
		}
	}

	if(!*p && !*str)
		return True;

	if (!*p && str[0] == '.' && str[1] == 0)
		return(True);
  
	if (!*str && *p == '?') {
		while (*p == '?')
			p++;
		return(!*p);
	}

	if(!*str && (*p == '*' && p[1] == '\0'))
		return True;

	return False;
}

void dump_data_pw(const char *msg, const uint8_t * data, size_t len)
{
#ifdef DEBUG_PASSWORD
	DEBUG(11, ("%s", msg));
	if (data != NULL && len > 0)
	{
		dump_data(11, data, len);
	}
#endif
}


/* see if a range of memory is all zero. A NULL pointer is considered
   to be all zero */
BOOL all_zero(const char *ptr, uint_t size)
{
	int i;
	if (!ptr) return True;
	for (i=0;i<size;i++) {
		if (ptr[i]) return False;
	}
	return True;
}


/*
  this is a warning hack. The idea is to use this everywhere that we
  get the "discarding const" warning from gcc, effectively moving all
  the warnings to this one place. That doesn't actually fix the
  problem of course, but it means that when we do get to cleaning them
  up we can do it by searching the code for discard_const.

  It also means that other error types aren't as swamped by the noise
  of hundreds of const warnings, so we are more likely to notice when
  we get new errors.

  Please only add more calls to this function when you find it
  _really_ hard to fix const warnings. Our aim is to eventually use
  this function in only a very few places.

  Also, please call this via the discard_const_p() macro interface, as that
  makes the return type safe.
*/
void *discard_const(const void *ptr)
{
	return (void *)ptr;
}