pop3.c

Vovida 社区开源的 SIP 协议源码

    if (t) {			/* flush end of text indicator */
      if (stream->debug) mm_dlog (t);
      fs_give ((void **) &t);
    }
  }

  if (auths) {			/* got any authenticators? */
    for (t = NIL; LOCAL->netstream && auths &&
	 (at = mail_lookup_auth (find_rightmost_bit (&auths)+1)); ) {
      if (t) {			/* previous authenticator failed? */
	sprintf (tmp,"Retrying using %.80s authentication after %.80s",
		 at->name,t);
	mm_log (tmp,NIL);
	fs_give ((void **) &t);
      }
      trial = 0;		/* initial trial count */
      tmp[0] = '\0';		/* empty buffer */
      if (LOCAL->netstream) do {
	if (tmp[0]) mm_log (tmp,WARN);
	if (pop3_send (stream,"AUTH",at->name) &&
	    (*at->client) (pop3_challenge,pop3_response,mb,stream,&trial,usr)&&
	    LOCAL->response) {
	  if (*LOCAL->response == '+') return LONGT;
	  if (!trial) {		/* if main program requested cancellation */
	    mm_log ("POP3 Authentication cancelled",ERROR);
	    return NIL;
	  }
	}
	t = cpystr (LOCAL->reply);
	sprintf (tmp,"Retrying %s authentication after %s",at->name,t);
      } while (LOCAL->netstream && trial && (trial < pop3_maxlogintrials));
    }
    if (t) {			/* previous authenticator failed? */
      sprintf (tmp,"Can not authenticate to POP3 server: %.80s",t);
      mm_log (tmp,ERROR);
      fs_give ((void **) &t);
    }
  }
  else if (stream->secure)
    mm_log ("Can't do secure authentication with this server",ERROR);
  else if (mb->authuser[0])
    mm_log ("Can't do /authuser with this server",ERROR);
  else {			/* traditional login */
    for (i = 0; LOCAL->netstream && (i < pop3_maxlogintrials); ++i) {
      tmp[0] = '\0';		/* prompt user for password */
      mm_login (mb,usr,tmp,i);
      if (tmp[0]) {		/* send login sequence */
	if (pop3_send (stream,"USER",usr) && pop3_send (stream,"PASS",tmp))
	  return LONGT;		/* success */
	mm_log (LOCAL->reply,WARN);
      }
      else {			/* user refused to give a password */
	mm_log ("Login aborted",ERROR);
	return NIL;
      }
    }
    mm_log ("Too many login failures",ERROR);
  }
  return NIL;			/* ran out of authenticators */
}

/* Get challenge to authenticator in binary
 * Accepts: stream
 *	    pointer to returned size
 * Returns: challenge or NIL if not challenge
 */

void *pop3_challenge (void *s,unsigned long *len)
{
  MAILSTREAM *stream = (MAILSTREAM *) s;
  return ((*LOCAL->response == '+') && (LOCAL->response[1] == ' ')) ?
    rfc822_base64 ((unsigned char *) LOCAL->reply,strlen (LOCAL->reply),len) :
      NIL;
}


/* Send authenticator response in BASE64
 * Accepts: MAIL stream
 *	    string to send
 *	    length of string
 * Returns: T if successful, else NIL
 */

long pop3_response (void *s,char *response,unsigned long size)
{
  MAILSTREAM *stream = (MAILSTREAM *) s;
  unsigned long i,j,ret;
  char *t,*u;
  if (response) {		/* make CRLFless BASE64 string */
    if (size) {
      for (t = (char *) rfc822_binary ((void *) response,size,&i),u = t,j = 0;
	   j < i; j++) if (t[j] > ' ') *u++ = t[j];
      *u = '\0';		/* tie off string for mm_dlog() */
      if (stream->debug) mm_dlog (t);
				/* append CRLF */
      *u++ = '\015'; *u++ = '\012'; *u = '\0';
      ret = net_sout (LOCAL->netstream,t,u - t);
      fs_give ((void **) &t);
    }
    else ret = net_sout (LOCAL->netstream,"\015\012",2);
  }
				/* abort requested */
  else ret = net_sout (LOCAL->netstream,"*\015\012",3);
				/* get response */
  if (!pop3_reply (stream)) ret = NIL;
  return ret;
}

/* POP3 mail close
 * Accepts: MAIL stream
 *	    option flags
 */

void pop3_close (MAILSTREAM *stream,long options)
{
  int silent = stream->silent;
  if (LOCAL) {			/* only if a file is open */
    if (LOCAL->netstream) {	/* close POP3 connection */
      stream->silent = T;
      if (options & CL_EXPUNGE) pop3_expunge (stream);
      stream->silent = silent;
      pop3_send (stream,"QUIT",NIL);
      mm_notify (stream,LOCAL->reply,BYE);
    }
				/* close POP3 connection */
    if (LOCAL->netstream) net_close (LOCAL->netstream);
    if (LOCAL->txt) fclose (LOCAL->txt);
    LOCAL->txt = NIL;
    if (LOCAL->response) fs_give ((void **) &LOCAL->response);
				/* nuke the local data */
    fs_give ((void **) &stream->local);
    stream->dtb = NIL;		/* log out the DTB */
  }
}

/* POP3 mail fetch fast information
 * Accepts: MAIL stream
 *	    sequence
 *	    option flags
 * This is ugly and slow
 */

void pop3_fetchfast (MAILSTREAM *stream,char *sequence,long flags)
{
  unsigned long i;
  MESSAGECACHE *elt;
				/* get sequence */
  if (stream && LOCAL && ((flags & FT_UID) ?
			  mail_uid_sequence (stream,sequence) :
			  mail_sequence (stream,sequence)))
    for (i = 1; i <= stream->nmsgs; i++)
      if ((elt = mail_elt (stream,i))->sequence &&
	  !(elt->day && !elt->rfc822_size)) {
	ENVELOPE **env = NIL;
	ENVELOPE *e = NIL;
	if (!stream->scache) env = &elt->private.msg.env;
	else if (stream->msgno == i) env = &stream->env;
	else env = &e;
	if (!*env || !elt->rfc822_size) {
	  STRING bs;
	  unsigned long hs;
	  char *ht = (*stream->dtb->header) (stream,i,&hs,NIL);
				/* need to make an envelope? */
	  if (!*env) rfc822_parse_msg (env,NIL,ht,hs,NIL,BADHOST,
				       stream->dtb->flags);
				/* need message size too, ugh */
	  if (!elt->rfc822_size) {
	    (*stream->dtb->text) (stream,i,&bs,FT_PEEK);
	    elt->rfc822_size = hs + SIZE (&bs) - GETPOS (&bs);
	  }
	}
				/* if need date, have date in envelope? */
	if (!elt->day && *env && (*env)->date)
	  mail_parse_date (elt,(*env)->date);
				/* sigh, fill in bogus default */
	if (!elt->day) mail_parse_date (elt,"01-JAN-1969 00:00:00 +0000");
	mail_free_envelope (&e);
      }
}

/* POP3 fetch header as text
 * Accepts: mail stream
 *	    message number
 *	    pointer to return size
 *	    flags
 * Returns: header text
 */

char *pop3_header (MAILSTREAM *stream,unsigned long msgno,unsigned long *size,
		   long flags)
{
  MESSAGECACHE *elt;
  if ((flags & FT_UID) && !(msgno = mail_msgno (stream,msgno))) return NIL;
				/* have header text? */
  if (!(elt = mail_elt (stream,msgno))->private.msg.header.text.data) {
    elt->private.msg.header.text.size = pop3_cache (stream,elt);
				/* read the header */
    fread (elt->private.msg.header.text.data = (unsigned char *)
	   fs_get ((size_t) elt->private.msg.header.text.size + 1),
	   (size_t) 1,(size_t) elt->private.msg.header.text.size,LOCAL->txt);
    elt->private.msg.header.text.data[elt->private.msg.header.text.size] ='\0';
  }
				/* return size of text */
  if (size) *size = elt->private.msg.header.text.size;
  return (char *) elt->private.msg.header.text.data;
}

/* POP3 fetch body
 * Accepts: mail stream
 *	    message number
 *	    pointer to stringstruct to initialize
 *	    flags
 * Returns: T if successful, else NIL
 */

long pop3_text (MAILSTREAM *stream,unsigned long msgno,STRING *bs,long flags)
{
  MESSAGECACHE *elt;
  INIT (bs,mail_string,(void *) "",0);
  if ((flags & FT_UID) && !(msgno = mail_msgno (stream,msgno))) return NIL;
  elt = mail_elt (stream,msgno);
  pop3_cache (stream,elt);	/* make sure cache loaded */
  if (!LOCAL->txt) return NIL;	/* error if don't have a file */
  if (!(flags & FT_PEEK)) {	/* mark seen if needed */
    elt->seen = T;
    mm_flags (stream,elt->msgno);
  }
  INIT (bs,file_string,(void *) LOCAL->txt,elt->rfc822_size);
  SETPOS (bs,LOCAL->hdrsize);	/* skip past header */
  return T;
}

/* POP3 cache message
 * Accepts: mail stream
 *	    message number
 * Returns: header size
 */

unsigned long pop3_cache (MAILSTREAM *stream,MESSAGECACHE *elt)
{
				/* already cached? */
  if (LOCAL->msgno != elt->msgno) {
				/* no, close current file */
    if (LOCAL->txt) fclose (LOCAL->txt);
    LOCAL->txt = NIL;
    LOCAL->msgno = LOCAL->hdrsize = 0;
    if (pop3_send_num (stream,"RETR",elt->msgno)) {
      LOCAL->msgno = elt->msgno;/* set as current message number */
				/* load the cache */
      LOCAL->txt = netmsg_slurp (LOCAL->netstream,&elt->rfc822_size,
				 &LOCAL->hdrsize);
    }
    else elt->deleted = T;
  }
  return LOCAL->hdrsize;
}

/* POP3 mail ping mailbox
 * Accepts: MAIL stream
 * Returns: T if stream alive, else NIL
 */

long pop3_ping (MAILSTREAM *stream)
{
  return pop3_send (stream,"NOOP",NIL);
}


/* POP3 mail check mailbox
 * Accepts: MAIL stream
 */

void pop3_check (MAILSTREAM *stream)
{
  if (pop3_ping (stream)) mm_log ("Check completed",NIL);
}


/* POP3 mail expunge mailbox
 * Accepts: MAIL stream
 */

void pop3_expunge (MAILSTREAM *stream)
{
  char tmp[MAILTMPLEN];
  unsigned long i = 1,n = 0;
  while (i <= stream->nmsgs) {
    if (mail_elt (stream,i)->deleted && pop3_send_num (stream,"DELE",i)) {
      mail_expunged (stream,i);
      n++;
    }
    else i++;			/* try next message */
  }
  if (!stream->silent) {	/* only if not silent */
    if (n) {			/* did we expunge anything? */
      sprintf (tmp,"Expunged %lu messages",n);
      mm_log (tmp,(long) NIL);
    }
    else mm_log ("No messages deleted, so no update needed",(long) NIL);
  }
}

/* POP3 mail copy message(s)
 * Accepts: MAIL stream
 *	    sequence
 *	    destination mailbox
 *	    option flags
 * Returns: T if copy successful, else NIL
 */

long pop3_copy (MAILSTREAM *stream,char *sequence,char *mailbox,long options)
{
  mailproxycopy_t pc =
    (mailproxycopy_t) mail_parameters (stream,GET_MAILPROXYCOPY,NIL);
  if (pc) return (*pc) (stream,sequence,mailbox,options);
  mm_log ("Copy not valid for POP3",ERROR);
  return NIL;
}


/* POP3 mail append message from stringstruct
 * Accepts: MAIL stream
 *	    destination mailbox
 *	    append callback
 *	    data for callback
 * Returns: T if append successful, else NIL
 */

long pop3_append (MAILSTREAM *stream,char *mailbox,append_t af,void *data)
{
  mm_log ("Append not valid for POP3",ERROR);
  return NIL;
}

/* Internal routines */


/* Post Office Protocol 3 send command with number argument
 * Accepts: MAIL stream
 *	    command
 *	    number
 * Returns: T if successful, NIL if failure
 */

long pop3_send_num (MAILSTREAM *stream,char *command,unsigned long n)
{
  char tmp[MAILTMPLEN];
  sprintf (tmp,"%lu",mail_uid (stream,n));
  return pop3_send (stream,command,tmp);
}


/* Post Office Protocol 3 send command
 * Accepts: MAIL stream
 *	    command
 *	    command argument
 * Returns: T if successful, NIL if failure
 */

long pop3_send (MAILSTREAM *stream,char *command,char *args)
{
  long ret;
  char *s = (char *) fs_get (strlen (command) + (args ? strlen (args) + 1: 0)
			     + 3);
  mail_lock (stream);		/* lock up the stream */
  if (!LOCAL->netstream) ret = pop3_fake (stream,"No-op dead stream");
  else {			/* build the complete command */
    if (args) sprintf (s,"%s %s",command,args);
    else strcpy (s,command);
    if (stream->debug) mm_dlog (s);
    strcat (s,"\015\012");
				/* send the command */
    ret = net_soutr (LOCAL->netstream,s) ? pop3_reply (stream) :
      pop3_fake (stream,"POP3 connection broken in command");
  }
  fs_give ((void **) &s);
  mail_unlock (stream);		/* unlock stream */
  return ret;
}

/* Post Office Protocol 3 get reply
 * Accepts: MAIL stream
 * Returns: T if success reply, NIL if error reply
 */

long pop3_reply (MAILSTREAM *stream)
{
  char *s;
				/* flush old reply */
  if (LOCAL->response) fs_give ((void **) &LOCAL->response);
  				/* get reply */
  if (!(LOCAL->response = net_getline (LOCAL->netstream)))
    return pop3_fake (stream,"POP3 connection broken in response");
  if (stream->debug) mm_dlog (LOCAL->response);
  LOCAL->reply = (s = strchr (LOCAL->response,' ')) ? s + 1 : LOCAL->response;
				/* return success or failure */
  return (*LOCAL->response =='+') ? T : NIL;
}


/* Post Office Protocol 3 set fake error
 * Accepts: MAIL stream
 *	    error text
 * Returns: NIL, always
 */

long pop3_fake (MAILSTREAM *stream,char *text)
{
  mm_notify (stream,text,BYE);	/* send bye alert */
  if (LOCAL->netstream) net_close (LOCAL->netstream);
  LOCAL->netstream = NIL;	/* farewell, dear TCP stream */
				/* flush any old reply */
  if (LOCAL->response) fs_give ((void **) &LOCAL->response);
  LOCAL->reply = text;		/* set up pseudo-reply string */
  return NIL;			/* return error code */
}