env_unix.c

来自「这是用C编写IMAP源代码」· C语言 代码 · 共 1,641 行 · 第 1/4 页

  if (lstat (name,sbuf)) return -1;
				/* forbid symbolic link */
  if ((sbuf->st_mode & S_IFMT) == S_IFLNK) {
    MM_LOG ("symbolic link on lock name",ERROR);
    syslog (LOG_CRIT,"SECURITY PROBLEM: symbolic link on lock name: %.80s",
	    name);
    return NIL;
  }
  return (long) sbuf->st_nlink;	/* return number of hard links */
}


/* Unlock file descriptor
 * Accepts: file descriptor
 *	    lock file name from lockfd()
 */

void unlockfd (int fd,char *lock)
{
				/* delete the file if no sharers */
  if (!flock (fd,LOCK_EX|LOCK_NB)) unlink (lock);
  flock (fd,LOCK_UN);		/* unlock it */
  close (fd);			/* close it */
}

/* Set proper file protection for mailbox
 * Accepts: mailbox name
 *	    actual file path name
 * Returns: T, always
 */

long set_mbx_protections (char *mailbox,char *path)
{
  struct stat sbuf;
  int mode = (int) mbx_protection;
  if (*mailbox == '#') {	/* possible namespace? */
      if (((mailbox[1] == 'f') || (mailbox[1] == 'F')) &&
	  ((mailbox[2] == 't') || (mailbox[2] == 'T')) &&
	  ((mailbox[3] == 'p') || (mailbox[3] == 'P')) &&
	  (mailbox[4] == '/')) mode = (int) ftp_protection;
      else if (((mailbox[1] == 'p') || (mailbox[1] == 'P')) &&
	       ((mailbox[2] == 'u') || (mailbox[2] == 'U')) &&
	       ((mailbox[3] == 'b') || (mailbox[3] == 'B')) &&
	       ((mailbox[4] == 'l') || (mailbox[4] == 'L')) &&
	       ((mailbox[5] == 'i') || (mailbox[5] == 'I')) &&
	       ((mailbox[6] == 'c') || (mailbox[6] == 'C')) &&
	       (mailbox[7] == '/')) mode = (int) public_protection;
      else if (((mailbox[1] == 's') || (mailbox[1] == 'S')) &&
	       ((mailbox[2] == 'h') || (mailbox[2] == 'H')) &&
	       ((mailbox[3] == 'a') || (mailbox[3] == 'A')) &&
	       ((mailbox[4] == 'r') || (mailbox[4] == 'R')) &&
	       ((mailbox[5] == 'e') || (mailbox[5] == 'E')) &&
	       ((mailbox[6] == 'd') || (mailbox[6] == 'D')) &&
	       (mailbox[7] == '/')) mode = (int) shared_protection;
  }
				/* if a directory */
  if (!stat (path,&sbuf) && ((sbuf.st_mode & S_IFMT) == S_IFDIR)) {
				/* set owner search if allow read or write */
    if (mode & 0600) mode |= 0100;
    if (mode & 060) mode |= 010;/* set group search if allow read or write */
    if (mode & 06) mode |= 01;	/* set world search if allow read or write */
				/* preserve directory SGID bit */
    if (sbuf.st_mode & S_ISGID) mode |= S_ISGID;
  }
  chmod (path,mode);		/* set the new protection, ignore failure */
  return LONGT;
}

/* Get proper directory protection
 * Accepts: mailbox name
 * Returns: directory mode, always
 */

long get_dir_protection (char *mailbox)
{
  if (*mailbox == '#') {	/* possible namespace? */
      if (((mailbox[1] == 'f') || (mailbox[1] == 'F')) &&
	  ((mailbox[2] == 't') || (mailbox[2] == 'T')) &&
	  ((mailbox[3] == 'p') || (mailbox[3] == 'P')) &&
	  (mailbox[4] == '/')) return ftp_dir_protection;
      else if (((mailbox[1] == 'p') || (mailbox[1] == 'P')) &&
	       ((mailbox[2] == 'u') || (mailbox[2] == 'U')) &&
	       ((mailbox[3] == 'b') || (mailbox[3] == 'B')) &&
	       ((mailbox[4] == 'l') || (mailbox[4] == 'L')) &&
	       ((mailbox[5] == 'i') || (mailbox[5] == 'I')) &&
	       ((mailbox[6] == 'c') || (mailbox[6] == 'C')) &&
	       (mailbox[7] == '/')) return public_dir_protection;
      else if (((mailbox[1] == 's') || (mailbox[1] == 'S')) &&
	       ((mailbox[2] == 'h') || (mailbox[2] == 'H')) &&
	       ((mailbox[3] == 'a') || (mailbox[3] == 'A')) &&
	       ((mailbox[4] == 'r') || (mailbox[4] == 'R')) &&
	       ((mailbox[5] == 'e') || (mailbox[5] == 'E')) &&
	       ((mailbox[6] == 'd') || (mailbox[6] == 'D')) &&
	       (mailbox[7] == '/')) return shared_dir_protection;
  }
  return dir_protection;
}

/* Determine default prototype stream to user
 * Accepts: type (NIL for create, T for append)
 * Returns: default prototype stream
 */

MAILSTREAM *default_proto (long type)
{
  myusername ();		/* make sure initialized */
				/* return default driver's prototype */
  return type ? appendProto : createProto;
}


/* Set up user flags for stream
 * Accepts: MAIL stream
 * Returns: MAIL stream with user flags set up
 */

MAILSTREAM *user_flags (MAILSTREAM *stream)
{
  int i;
  myusername ();		/* make sure initialized */
  for (i = 0; i < NUSERFLAGS && userFlags[i]; ++i)
    if (!stream->user_flags[i]) stream->user_flags[i] = cpystr (userFlags[i]);
  return stream;
}


/* Return nth user flag
 * Accepts: user flag number
 * Returns: flag
 */

char *default_user_flag (unsigned long i)
{
  myusername ();		/* make sure initialized */
  return userFlags[i];
}

/* Process rc file
 * Accepts: file name
 *	    .mminit flag
 * Don't even think of using this feature.
 */

void dorc (char *file,long flag)
{
  int i;
  char *s,*t,*k,tmp[MAILTMPLEN],tmpx[MAILTMPLEN];
  extern MAILSTREAM CREATEPROTO;
  extern MAILSTREAM EMPTYPROTO;
  DRIVER *d;
  FILE *f;
				/* no file or ill-advised usage */
  if ((f = fopen (file ? file : SYSCONFIG,"r")) &&
      (s = fgets (tmp,MAILTMPLEN,f)) && (t = strchr (s,'\n')) &&
      (flag || (!strncmp (s,RISKPHRASE,sizeof (RISKPHRASE)-1) &&
		(s = fgets (tmp,MAILTMPLEN,f)) && (t = strchr (s,'\n'))))) do {
    *t++ = '\0';		/* tie off line, find second space */
    if ((k = strchr (s,' ')) && (k = strchr (++k,' '))) {
      *k++ = '\0';		/* tie off two words */
      if (!compare_cstring (s,"set keywords") && !userFlags[0]) {
	k = strtok (k,", ");	/* yes, get first keyword */
				/* copy keyword list */
	for (i = 0; k && i < NUSERFLAGS; ++i) if (strlen (k) <= MAXUSERFLAG) {
	  if (userFlags[i]) fs_give ((void **) &userFlags[i]);
	  userFlags[i] = cpystr (k);
	  k = strtok (NIL,", ");
	}
	if (flag) break;	/* found "set keywords" in .mminit */
      }
      else if (!flag) {		/* none of these valid in .mminit */

	if (myUserName) {	/* only valid if logged in */
	  if (!compare_cstring (s,"set new-folder-format")) {
	    if (!compare_cstring (k,"same-as-inbox"))
	      createProto = ((d = mail_valid (NIL,"INBOX",NIL)) &&
			     compare_cstring (d->name,"dummy")) ?
			       ((*d->open) (NIL)) : &CREATEPROTO;
	    else if (!compare_cstring (k,"system-standard"))
	      createProto = &CREATEPROTO;
	    else {		/* see if a driver name */
	      for (d = (DRIVER *) mail_parameters (NIL,GET_DRIVERS,NIL);
		   d && compare_cstring (d->name,k); d = d->next);
	      if (d) createProto = (*d->open) (NIL);
	      else {		/* duh... */
		sprintf (tmpx,"Unknown new folder format in %s: %s",file,k);
		MM_LOG (tmpx,WARN);
	      }
	    }
	  }
	  if (!compare_cstring (s,"set empty-folder-format")) {
	    if (!compare_cstring (k,"same-as-inbox"))
	      appendProto = ((d = mail_valid (NIL,"INBOX",NIL)) &&
			     compare_cstring (d->name,"dummy")) ?
			       ((*d->open) (NIL)) : &EMPTYPROTO;
	    else if (!compare_cstring (k,"system-standard"))
	      appendProto = &EMPTYPROTO;
	    else {		/* see if a driver name */
	      for (d = (DRIVER *) mail_parameters (NIL,GET_DRIVERS,NIL);
		   d && compare_cstring (d->name,k); d = d->next);
	      if (d) appendProto = (*d->open) (NIL);
	      else {		/* duh... */
		sprintf (tmpx,"Unknown empty folder format in %s: %s",file,k);
		MM_LOG (tmpx,WARN);
	      }
	    }
	  }
	}

	if (!compare_cstring (s,"set local-host")) {
	  fs_give ((void **) &myLocalHost);
	  myLocalHost = cpystr (k);
	}
	else if (!compare_cstring (s,"set news-active-file")) {
	  fs_give ((void **) &newsActive);
	  newsActive = cpystr (k);
	}
	else if (!compare_cstring (s,"set news-spool-directory")) {
	  fs_give ((void **) &newsSpool);
	  newsSpool = cpystr (k);
	}
	else if (!compare_cstring (s,"set news-state-file")) {
	  fs_give ((void **) &myNewsrc);
	  myNewsrc = cpystr (k);
	}
	else if (!compare_cstring (s,"set ftp-export-directory")) {
	  fs_give ((void **) &ftpHome);
	  ftpHome = cpystr (k);
	}
	else if (!compare_cstring (s,"set public-home-directory")) {
	  fs_give ((void **) &publicHome);
	  publicHome = cpystr (k);
	}
	else if (!compare_cstring (s,"set shared-home-directory")) {
	  fs_give ((void **) &sharedHome);
	  sharedHome = cpystr (k);
	}
	else if (!compare_cstring (s,"set system-inbox")) {
	  fs_give ((void **) &sysInbox);
	  sysInbox = cpystr (k);
	}
	else if (!compare_cstring (s,"set mail-subdirectory")) {
	  fs_give ((void **) &mailsubdir);
	  mailsubdir = cpystr (k);
	}
	else if (!compare_cstring (s,"set from-widget"))
	  mail_parameters (NIL,SET_FROMWIDGET,
			   compare_cstring (k,"header-only") ?
			   VOIDT : NIL);

	else if (!compare_cstring (s,"set rsh-command"))
	  mail_parameters (NIL,SET_RSHCOMMAND,(void *) k);
	else if (!compare_cstring (s,"set rsh-path"))
	  mail_parameters (NIL,SET_RSHPATH,(void *) k);
	else if (!compare_cstring (s,"set ssh-command"))
	  mail_parameters (NIL,SET_SSHCOMMAND,(void *) k);
	else if (!compare_cstring (s,"set ssh-path"))
	  mail_parameters (NIL,SET_SSHPATH,(void *) k);
	else if (!compare_cstring (s,"set tcp-open-timeout"))
	  mail_parameters (NIL,SET_OPENTIMEOUT,(void *) atol (k));
	else if (!compare_cstring (s,"set tcp-read-timeout"))
	  mail_parameters (NIL,SET_READTIMEOUT,(void *) atol (k));
	else if (!compare_cstring (s,"set tcp-write-timeout"))
	  mail_parameters (NIL,SET_WRITETIMEOUT,(void *) atol (k));
	else if (!compare_cstring (s,"set rsh-timeout"))
	  mail_parameters (NIL,SET_RSHTIMEOUT,(void *) atol (k));
	else if (!compare_cstring (s,"set ssh-timeout"))
	  mail_parameters (NIL,SET_SSHTIMEOUT,(void *) atol (k));
	else if (!compare_cstring (s,"set maximum-login-trials"))
	  mail_parameters (NIL,SET_MAXLOGINTRIALS,(void *) atol (k));
	else if (!compare_cstring (s,"set lookahead"))
	  mail_parameters (NIL,SET_LOOKAHEAD,(void *) atol (k));
	else if (!compare_cstring (s,"set prefetch"))
	  mail_parameters (NIL,SET_PREFETCH,(void *) atol (k));
	else if (!compare_cstring (s,"set close-on-error"))
	  mail_parameters (NIL,SET_CLOSEONERROR,(void *) atol (k));
	else if (!compare_cstring (s,"set imap-port"))
	  mail_parameters (NIL,SET_IMAPPORT,(void *) atol (k));
	else if (!compare_cstring (s,"set pop3-port"))
	  mail_parameters (NIL,SET_POP3PORT,(void *) atol (k));
	else if (!compare_cstring (s,"set uid-lookahead"))
	  mail_parameters (NIL,SET_UIDLOOKAHEAD,(void *) atol (k));
	else if (!compare_cstring (s,"set try-ssl-first"))
	  mail_parameters (NIL,SET_TRYSSLFIRST,(void *) atol (k));

	else if (!compare_cstring (s,"set mailbox-protection"))
	  mbx_protection = atol (k);
	else if (!compare_cstring (s,"set directory-protection"))
	  dir_protection = atol (k);
	else if (!compare_cstring (s,"set lock-protection"))
	  lock_protection = atol (k);
	else if (!compare_cstring (s,"set ftp-protection"))
	  ftp_protection = atol (k);
	else if (!compare_cstring (s,"set public-protection"))
	  public_protection = atol (k);
	else if (!compare_cstring (s,"set shared-protection"))
	  shared_protection = atol (k);
	else if (!compare_cstring (s,"set ftp-directory-protection"))
	  ftp_dir_protection = atol (k);
	else if (!compare_cstring (s,"set public-directory-protection"))
	  public_dir_protection = atol (k);
	else if (!compare_cstring (s,"set shared-directory-protection"))
	  shared_dir_protection = atol (k);
	else if (!compare_cstring (s,"set dot-lock-file-timeout"))
	  locktimeout = atoi (k);
	else if (!compare_cstring (s,"set disable-fcntl-locking"))
	  disableFcntlLock = atoi (k);
	else if (!compare_cstring (s,"set disable-lock-warning"))
	  disableLockWarning = atoi (k);
	else if (!compare_cstring (s,"set hide-dot-files"))
	  hideDotFiles = atoi (k);
	else if (!compare_cstring (s,"set list-maximum-level"))
	  list_max_level = atol (k);
	else if (!compare_cstring (s,"set trust-dns"))
	  mail_parameters (NIL,SET_TRUSTDNS,(void *) atol (k));
	else if (!compare_cstring (s,"set sasl-uses-ptr-name"))
	  mail_parameters (NIL,SET_SASLUSESPTRNAME,(void *) atol (k));
	else if (!compare_cstring (s,"set network-filesystem-stat-bug"))
	  netfsstatbug = atoi (k);

	else if (!file) {	/* only allowed in system init */
	  if (!compare_cstring (s,"set black-box-directory") &&
	      !blackBoxDir) blackBoxDir = cpystr (k);
	  else if (!compare_cstring(s,"set black-box-default-home-directory")&&
		   blackBoxDir && !blackBoxDefaultHome)
	    blackBoxDefaultHome = cpystr (k);
	  else if (!compare_cstring (s,"set anonymous-home-directory") &&
		   !anonymousHome) anonymousHome = cpystr (k);
	  else if (!compare_cstring (s,"set disable-plaintext"))
	    disablePlaintext = atoi (k);
	  else if (!compare_cstring (s,"set allowed-login-attempts"))
	    logtry = atoi (k);
	  else if (!compare_cstring (s,"set chroot-server"))
	    closedBox = atoi (k);
	  else if (!compare_cstring (s,"set restrict-mailbox-access")) {
	    for (k = strtok (k,", "); k; k = strtok (NIL,", ")) {
	      if (!compare_cstring (k,"root")) restrictBox |= RESTRICTROOT;
	      else if (!compare_cstring (k,"otherusers"))
		restrictBox |= RESTRICTOTHERUSER;
	      else if (!compare_cstring (k,"all")) restrictBox = -1;
	    }
	  }
	  else if (!compare_cstring (s,"set advertise-the-world"))
	    advertisetheworld = atoi (k);
	  else if (!compare_cstring (s,"set limited-advertise"))
	    limitedadvertise = atoi (k);
	  else if (!compare_cstring
		   (s,"set disable-automatic-shared-namespaces"))
	    noautomaticsharedns = atoi (k);
	  else if (!compare_cstring (s,"set allow-user-config"))
	    allowuserconfig = atoi (k);
	  else if (!compare_cstring (s,"set allow-reverse-dns"))
	    mail_parameters (NIL,SET_ALLOWREVERSEDNS,(void *) atol (k));
	}
      }
    }
  } while ((s = fgets (tmp,MAILTMPLEN,f)) && (t = strchr (s,'\n')));
  if (f) fclose (f);		/* flush the file */
}

/* INBOX create function for tmail/dmail use only
 * Accepts: mail stream
 *	    path name buffer, preloaded with driver-dependent path
 * Returns: T on success, NIL on failure
 *
 * This routine is evil and a truly incredible kludge.  It is private for
 * tmail/dmail and is not supported for any other application.
 */

long path_create (MAILSTREAM *stream,char *path)
{
  long ret;
  short rsave = restrictBox;
  restrictBox = NIL;		/* can't restrict */
  if (blackBox) {		/* if black box */
				/* toss out driver dependent names */
    printf (path,"%s/INBOX",mymailboxdir ());
    blackBox = NIL;		/* well that's evil - evil is going on */
    ret = mail_create (stream,path);
    blackBox = T;		/* restore the box */
  }
				/* easy thing otherwise */
  else ret = mail_create (stream,path);
  restrictBox = rsave;		/* restore restrictions */
  return ret;
}

/* Default block notify routine
 * Accepts: reason for calling
 *	    data
 * Returns: data
 */

void *mm_blocknotify (int reason,void *data)
{
  void *ret = data;
  switch (reason) {
  case BLOCK_SENSITIVE:		/* entering sensitive code */
    ret = (void *) alarm (0);
    break;
  case BLOCK_NONSENSITIVE:	/* exiting sensitive code */
    if ((unsigned int) data) alarm ((unsigned int) data);
    break;
  default:			/* ignore all other reasons */
    break;
  }
  return ret;
}