env_unix.c

mgcp协议源代码。支持多种编码：g711

  long port;
  struct servent *sv;
  struct sockaddr_in sin;
  int i = sizeof (struct sockaddr_in);
  /* Don't use tcp_clienthost() since reverse DNS problems may slow down the
   * greeting message and cause the client to time out.
   */
  char *client = getpeername (0,(struct sockaddr *) &sin,(void *) &i) ?
    "UNKNOWN" : inet_ntoa (sin.sin_addr);
  switch (i = umask (022)) {	/* check old umask */
  case 0:			/* definitely unreasonable */
  case 022:			/* don't need to change it */
    break;
  default:			/* already was a reasonable value */
    umask (i);			/* so change it back */
  }
				/* set server name in syslog */
  if (server) openlog (server,LOG_PID,LOG_MAIL);
  if (service && altservice && ((port = tcp_serverport ()) >= 0)) {
    if ((sv = getservbyname (service,"tcp")) && (port == ntohs (sv->s_port)))
      syslog (LOG_DEBUG,"%s service init from %s",service,client);
    else if ((sv = getservbyname (altservice,"tcp")) &&
	     (port == ntohs (sv->s_port)))
      syslog (LOG_DEBUG,"%s alternative service init from %s",
	      altservice,client);
    else syslog (LOG_DEBUG,"port %ld service init from %s",port,client);
  }
				/* set SASL name */
  if (sasl) mail_parameters (NIL,SET_SERVICENAME,(void *) sasl);
  arm_signal (SIGALRM,clkint);	/* prepare for clock interrupt */
  arm_signal (SIGUSR2,kodint);	/* prepare for Kiss Of Death */
  arm_signal (SIGHUP,hupint);	/* prepare for hangup */
  arm_signal (SIGTERM,trmint);	/* prepare for termination */
}

/* Wait for stdin input
 * Accepts: timeout in seconds
 * Returns: T if have input on stdin, else NIL
 */

long server_input_wait (long seconds)
{
  fd_set rfd,efd;
  struct timeval tmo;
  FD_ZERO (&rfd);
  FD_ZERO (&efd);
  FD_SET (0,&rfd);
  FD_SET (0,&efd);
  tmo.tv_sec = seconds; tmo.tv_usec = 0;
  return select (1,&rfd,0,&efd,&tmo) ? LONGT : NIL;
}

/* Server log in
 * Accepts: user name string
 *	    password string
 *	    authenticating user name string
 *	    argument count
 *	    argument vector
 * Returns: T if password validated, NIL otherwise
 */

long server_login (char *user,char *pwd,char *authuser,int argc,char *argv[])
{
  char *s,usr[MAILTMPLEN],ausr[MAILTMPLEN];
  struct passwd *pw;
  struct passwd *logpw = NIL;
				/* cretins still haven't given up */
  if ((strlen (user) >= MAILTMPLEN) ||
      (authuser && (strlen (authuser) >= MAILTMPLEN))) {
    syslog (LOG_ALERT|LOG_AUTH,"SYSTEM BREAK-IN ATTEMPT, host=%.80s",
	    tcp_clienthost ());
    logtry = 0;			/* render this session useless */
  }
  else {
    strcpy (usr,user);		/* make writeable copy of user */
    if (auth_md5.server) {	/* using CRAM-MD5 authentication? */
				/* make sure user exists */
      if ((pw = getpwnam (usr)) || (pw = getpwnam (lcase (usr)))) {
				/* default authentication identity */
	if (!(authuser && *authuser))
	  s = auth_md5_pwd (strcpy (ausr,pw->pw_name));
				/* otherwise use given authentication id */
	else if (!(s = auth_md5_pwd (strcpy (ausr,authuser))))
	  s = auth_md5_pwd (lcase (ausr));
	if (s) {		/* have a CRAM-MD5 password? */
	  if (!strcmp (s,pwd) && strcmp (s,pwd+1)) logpw = pw;
				/* erase sensitive information */
	  memset (s,0,strlen (s));
	  fs_give ((void **) &s);
	}
	else syslog (LOG_NOTICE|LOG_AUTH,
		     "Login %s failed: %s has no CRAM-MD5 password host=%.80s",
		     usr,ausr,tcp_clienthost ());
      }
    }
				/* ordinary password authentication */
    else if ((authuser && *authuser) ?
	     (((pw = getpwnam (strcpy (ausr,authuser))) ||
	       (pw = getpwnam (lcase (ausr)))) &&
	      (checkpw (pw,pwd,argc,argv) ||
	       ((*pwd == ' ') && checkpw (getpwnam (ausr),pwd+1,argc,argv))) &&
	      ((pw = getpwnam (strcpy (usr,user))) ||
	       (pw = getpwnam (lcase (usr))))) :
	     (((pw = getpwnam (strcpy (ausr,user))) ||
	       (pw = getpwnam (lcase (ausr)))) &&
	      ((pw = checkpw (pw,pwd,argc,argv)) ||
	       ((*pwd == ' ') &&
		(pw = checkpw (getpwnam(ausr),pwd+1,argc,argv))))))
      logpw = pw;

    if (logtry <= 0)		/* excessive login failures */
      syslog (LOG_NOTICE|LOG_AUTH,
	      "Login attempt after lockout user=%.80s host=%.80s",
	      user,tcp_clienthost ());
    else if (!logpw)		/* login failed */
      syslog (LOG_NOTICE|LOG_AUTH,"%s user=%.80s host=%.80s",
	      (logtry-- > 0) ? "Login failure" : "Excessive login attempts",
	      user,tcp_clienthost ());
#ifndef PLAINTEXT_DISABLED
				/* validate with authentication ID */
    else if (pw_login (pw,ausr,pw->pw_name,pw->pw_dir,argc,argv)) return T;
#endif
  }
  sleep (3);			/* slow down possible cracker */
  return NIL;
}

/* Authenticated server log in
 * Accepts: user name string
 *	    authenticating user name string
 *	    argument count
 *	    argument vector
 * Returns: T if password validated, NIL otherwise
 */

long authserver_login (char *user,char *authuser,int argc,char *argv[])
{
  struct passwd *pw = getpwnam (user);
  return pw ? pw_login (pw,authuser,pw->pw_name,pw->pw_dir,argc,argv) : NIL;
}


/* Log in as anonymous daemon
 * Accepts: argument count
 *	    argument vector
 * Returns: T if successful, NIL if error
 */

long anonymous_login (int argc,char *argv[])
{
  struct passwd *pw = getpwnam ((char *) anonymous_user);
				/* log in Mr. A. N. Onymous */
  return pw ? pw_login (pw,NIL,NIL,NIL,argc,argv) : NIL;
}


/* Finish log in and environment initialization
 * Accepts: passwd struct for loginpw()
 *	    authentication user name
 *	    user name (NIL for anonymous)
 *	    home directory (NIL for anonymous)
 *	    argument count
 *	    argument vector
 * Returns: T if successful, NIL if error
 */

long pw_login (struct passwd *pw,char *authuser,char *user,char *home,int argc,
	       char *argv[])
{
  long ret = NIL;
				/* OK if matches authorization ID */
  if (authuser && strcmp (authuser,pw->pw_name)) {
    struct group *gr = getgrnam ((char *) admin_grp);
    char **t;
				/* scan list of mail administrators */
    for (t = gr ? gr->gr_mem : NIL; t; t++) if (!strcmp (authuser,*t)) {
      syslog (LOG_NOTICE|LOG_AUTH,"Admin %s override of user=%s host=%.80s",
	      authuser,pw->pw_name,tcp_clienthost ());
      return pw_login (pw,NIL,user,home,argc,argv);
    }
    syslog (LOG_NOTICE|LOG_AUTH,
	    "Login %s failed: invalid authentication ID %s host=%.80s",
	    pw->pw_name,authuser,tcp_clienthost ());
  }
  else if (!pw->pw_uid);	/* disallow UID 0 */
				/* if same as EUID, treat as application */
  else if (pw->pw_uid == geteuid ()) ret = env_init (user,home);
  else {			/* in case loginpw() smashes these */
    char *u = user ? cpystr (user) : NIL;
    char *h = home ? cpystr (home) : NIL;
#ifdef CHROOT_SERVER
				/* paranoid site, lock out other directories */
    if (chdir (home ? home : ANONYMOUSHOME) ||
	chroot (home ? home : ANONYMOUSHOME)) return NIL;
    home = "/";			/* home directory now root */
    closedBox = T;		/* flag that this is a closed box */
#endif
				/* log the user in */
    if (loginpw (pw,argc,argv)) ret = env_init (u,h);
    if (h) fs_give ((void **) &h);
    if (u) fs_give ((void **) &u);
  }
  if (ret) chdir (myhomedir ());/* make sure at home directory */
  return ret;			/* return status */
}

/* Initialize environment
 * Accepts: user name
 *	    home directory name
 * Returns: T, always
 */

long env_init (char *user,char *home)
{
  extern MAILSTREAM CREATEPROTO;
  extern MAILSTREAM EMPTYPROTO;
  struct passwd *pw;
  struct stat sbuf;
  char tmp[MAILTMPLEN];
  if (myUserName) fatal ("env_init called twice!");
				/* myUserName must be set before dorc() call */
  myUserName = cpystr (user ? user : (char *) anonymous_user);
  if (closedBox) {		/* closed box server */
				/* standard user can only reference home */
    if (user) nslist[0] = &nshome;
    else {			/* anonymous user */
      nslist[0] = &nsblackother; /* set root */
      anonymous = T;		/* flag as anonymous */
    }
    nslist[1] = nslist[2] = NIL;/* can't reference anything else */
				/* make sure user rc files don't try these */
    blackBoxDir = blackBoxDefaultHome = anonymousHome = "";
    sysInbox = cpystr ("INBOX");/* make system INBOX */
  }

  else {			/* open or black box */
				/* do systemwide configuration */
    dorc ("/etc/c-client.cf",NIL);
    if (!anonymousHome) anonymousHome = cpystr (ANONYMOUSHOME);
    if (user) {			/* remember user name and home directory */
      if (blackBoxDir) {	/* build black box directory name */
	sprintf (tmp,"%s/%s",blackBoxDir,myUserName);
				/* if black box if exists and directory */
	if (home = (!stat (tmp,&sbuf) && (sbuf.st_mode & S_IFDIR)) ?
	    tmp : blackBoxDefaultHome) {
	  sysInbox = (char *) fs_get (strlen (home) + 7);
				/* set system INBOX */
	  sprintf (sysInbox,"%s/INBOX",home);
	  blackBox = T;		/* mark that it's a black box */
				/* mbox meaningless if black box */
	  mail_parameters (NIL,DISABLE_DRIVER,(void *) "mbox");
	}
      }
      if (blackBox)		/* black box? */
	nslist[0] = &nshome,nslist[1] = &nsblackother,nslist[2] = &nsshared;
      else {			/* not a black box */
	nslist[0] = &nshome;	/* home directory */
				/* other users */
	nslist[1] = &nsunixother;
#ifdef ADVERTISE_THE_WORLD
	nslist[2] = &nsworld;	/* you probably don't want to do this! */
#else
	nslist[2] = &nsshared;	/* what, me paranoid? */
#endif
				/* make sure user rc files don't try this */
	blackBoxDir = blackBoxDefaultHome = "";
      }
    }
    else {			/* anonymous user */
      nslist[0] = nslist[1] = NIL,nslist[2] = &nsftp;
      sprintf (tmp,"%s/INBOX",home = anonymousHome);
      sysInbox = cpystr (tmp);	/* make system INBOX */
      anonymous = T;		/* flag as anonymous */
				/* make sure an error message happens */
      if (!blackBoxDir) blackBoxDir = blackBoxDefaultHome = anonymousHome;
    }
  }

				/* use real home directory */
  myHomeDir = cpystr (home ? home : ANONYMOUSHOME);
  dorc (strcat (strcpy (tmp,myHomeDir),"/.mminit"),T);
  dorc (strcat (strcpy (tmp,myHomeDir),"/.imaprc"),NIL);
  if (!closedBox) {		/* can't do this on closed server */
				/* #ftp namespace */
    if (!ftpHome && (pw = getpwnam ("ftp"))) ftpHome = cpystr (pw->pw_dir);
				/* #public namespace */
    if (!publicHome && (pw = getpwnam ("imappublic")))
      publicHome = cpystr (pw->pw_dir);
				/* #shared namespace */
    if (!anonymous && !sharedHome && (pw = getpwnam ("imapshared")))
      sharedHome = cpystr (pw->pw_dir);
  }
  if (!myLocalHost) mylocalhost ();
  if (!myNewsrc) myNewsrc = cpystr(strcat (strcpy (tmp,myHomeDir),"/.newsrc"));
  if (!newsActive) newsActive = cpystr (ACTIVEFILE);
  if (!newsSpool) newsSpool = cpystr (NEWSSPOOL);
				/* force default prototype to be set */
  if (!createProto) createProto = &CREATEPROTO;
  if (!appendProto) appendProto = &EMPTYPROTO;
				/* re-do open action to get flags */
  (*createProto->dtb->open) (NIL);
  endpwent ();			/* close pw database */
  return T;
}
 
/* Return my user name
 * Accepts: pointer to optional flags
 * Returns: my user name
 */

char *myusername_full (unsigned long *flags)
{
  char *ret = (char *) unlogged_user;
  if (!myUserName) {		/* get user name if don't have it yet */
    struct passwd *pw;
    struct stat sbuf;
    unsigned long euid = geteuid ();
    char *s = (char *) (euid ? getlogin () : NIL);
				/* look up getlogin() user name or EUID */
    if (!((s && *s && (strlen (s) < NETMAXUSER) && (pw = getpwnam (s)) &&
	   (pw->pw_uid == euid)) || (pw = getpwuid (euid))))
      fatal ("Unable to look up user name");
				/* init environment if not root */
    if (euid) env_init (pw->pw_name,((s = getenv ("HOME")) && *s &&
				     (strlen (s) < NETMAXMBX) &&
				     !stat (s,&sbuf) &&
				     ((sbuf.st_mode & S_IFMT) == S_IFDIR)) ?
			s : pw->pw_dir);
    else ret = pw->pw_name;	/* in case UID 0 user is other than root */
  }
  if (myUserName) {		/* logged in? */
    if (flags) *flags = anonymous ? MU_ANONYMOUS : MU_LOGGEDIN;
    ret = myUserName;		/* return user name */
  }
  else if (flags) *flags = MU_NOTLOGGEDIN;
  return ret;
}


/* Return my local host name
 * Returns: my local host name
 */

char *mylocalhost ()
{
  char tmp[MAILTMPLEN];
  struct hostent *host_name;
  if (!myLocalHost) {
    gethostname(tmp,MAILTMPLEN);/* get local host name */
    myLocalHost = cpystr ((host_name = gethostbyname (tmp)) ?
			  host_name->h_name : tmp);
  }
  return myLocalHost;
}

/* Return my home directory name
 * Returns: my home directory name
 */

char *myhomedir ()