imapd.c

Vovida 社区开源的 SIP 协议源码

/*
 * Program:	IMAP4rev1 server
 *
 * Author:	Mark Crispin
 *		Networks and Distributed Computing
 *		Computing & Communications
 *		University of Washington
 *		Administration Building, AG-44
 *		Seattle, WA  98195
 *		Internet: [e-mail]
 *
 * Date:	5 November 1990
 * Last Edited:	13 October 2000
 *
 * Copyright 2000 by the University of Washington
 *
 *  Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose and without fee is hereby granted, provided
 * that the above copyright notice appears in all copies and that both the
 * above copyright notice and this permission notice appear in supporting
 * documentation, and that the name of the University of Washington not be
 * used in advertising or publicity pertaining to distribution of the software
 * without specific, written prior permission.  This software is made
 * available "as is", and
 * THE UNIVERSITY OF WASHINGTON DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED,
 * WITH REGARD TO THIS SOFTWARE, INCLUDING WITHOUT LIMITATION ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, AND IN
 * NO EVENT SHALL THE UNIVERSITY OF WASHINGTON BE LIABLE FOR ANY SPECIAL,
 * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, TORT
 * (INCLUDING NEGLIGENCE) OR STRICT LIABILITY, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

/* Primary I/O calls */

#define PBIN getchar		/* primary byte input */
				/* primary string input */
#define PSIN(s,n) fgets (s,n,stdin)
#define PBOUT(c) putchar (c)	/* primary byte output */
				/* primary string output */
#define PSOUT(s) fputs (s,stdout)
#define PFLUSH fflush (stdout)	/* flush primary output */
#define CRLF PSOUT ("\015\012")	/* primary output terpri */
				/* server input wait */
#define INWAIT(t) server_input_wait (t)


/* Parameter files */

#include <stdio.h>
#include <ctype.h>
#include <errno.h>
extern int errno;		/* just in case */
#include <signal.h>
#include <time.h>
#include "c-client.h"
#include <sys/stat.h>


/* Timeouts and timers */

#define MINUTES *60

#define LOGINTIMEOUT 3 MINUTES	/* not logged in autologout timer */
#define TIMEOUT 30 MINUTES	/* RFC 2060 minimum autologout timer */
#define ALERTTIMER 1 MINUTES	/* alert check timer */
#define IDLETIMER 1 MINUTES	/* IDLE command poll timer */
#define CHECKTIMER 15 MINUTES	/* IDLE command last checkpoint timer */


#define LITSTKLEN 20		/* length of literal stack */
#define MAXCLIENTLIT 10000	/* maximum non-APPEND client literal size */
#define TMPLEN 8192		/* size of temporary buffers */


/* Server states */

#define LOGIN 0
#define SELECT 1
#define OPEN 2
#define LOGOUT 3

/* Body text fetching */

typedef struct text_args {
  char *section;		/* body section */
  STRINGLIST *lines;		/* header lines */
  unsigned long first;		/* first octet to fetch */
  unsigned long last;		/* number of octets to fetch */
  long flags;			/* flags */
} TEXTARGS;


/* Append data */

typedef struct append_data {
  char *arg;			/* append argument pointer */
  char *flags;			/* message flags */
  char *date;			/* message date */
  char *msg;			/* message text */
  STRING *message;		/* message stringstruct */
} APPENDDATA;


/* Message pointer */

typedef struct msg_data {
  MAILSTREAM *stream;		/* stream */
  unsigned long msgno;		/* message number */
  char *flags;			/* current flags */
  char *date;			/* current date */
  STRING *message;		/* strintstruct of message */
} MSGDATA;

/* Function prototypes */

int main (int argc,char *argv[]);
void ping_mailbox (unsigned long uid);
time_t palert (char *file,time_t oldtime);
void msg_string_init (STRING *s,void *data,unsigned long size);
char msg_string_next (STRING *s);
void msg_string_setpos (STRING *s,unsigned long i);
void new_flags (MAILSTREAM *stream);
void clkint (void);
void kodint (void);
void hupint (void);
void trmint (void);
void slurp (char *s,int n);
char inchar (void);
char *flush (void);
char *parse_astring (char **arg,unsigned long *i,char *del);
char *snarf (char **arg);
char *snarf_list (char **arg);
STRINGLIST *parse_stringlist (char **s,int *list);
long parse_criteria (SEARCHPGM *pgm,char **arg,unsigned long maxmsg,
		     unsigned long maxuid,unsigned long depth);
long parse_criterion (SEARCHPGM *pgm,char **arg,unsigned long msgmsg,
		      unsigned long maxuid,unsigned long depth);
long crit_date (unsigned short *date,char **arg);
long crit_date_work (unsigned short *date,char **arg);
long crit_set (SEARCHSET **set,char **arg,unsigned long maxima);
long crit_number (unsigned long *number,char **arg);
long crit_string (STRINGLIST **string,char **arg);

void fetch (char *t,unsigned long uid);
typedef void (*fetchfn_t) (unsigned long i,void *args);
void fetch_work (char *t,unsigned long uid,fetchfn_t f[],void *fa[]);
void fetch_bodystructure (unsigned long i,void *args);
void fetch_body (unsigned long i,void *args);
void fetch_body_part_mime (unsigned long i,void *args);
void fetch_body_part_contents (unsigned long i,void *args);
void fetch_body_part_header (unsigned long i,void *args);
void fetch_body_part_text (unsigned long i,void *args);
void remember (unsigned long uid,char *id,SIZEDTEXT *st);
void fetch_envelope (unsigned long i,void *args);
void fetch_encoding (unsigned long i,void *args);
void changed_flags (unsigned long i,int f);
void fetch_rfc822_header_lines (unsigned long i,void *args);
void fetch_rfc822_header_lines_not (unsigned long i,void *args);
void fetch_flags (unsigned long i,void *args);
void put_flag (int *c,char *s);
void fetch_internaldate (unsigned long i,void *args);
void fetch_uid (unsigned long i,void *args);
void fetch_rfc822 (unsigned long i,void *args);
void fetch_rfc822_header (unsigned long i,void *args);
void fetch_rfc822_size (unsigned long i,void *args);
void fetch_rfc822_text (unsigned long i,void *args);
void penv (ENVELOPE *env);
void pbodystructure (BODY *body);
void pbody (BODY *body);
void pparam (PARAMETER *param);
void paddr (ADDRESS *a);
void pnum (unsigned long i);
void pstring (char *s);
void pnstring (char *label,SIZEDTEXT *st);
void pastring (char *s);
void pbodypartstring (unsigned long msgno,char *id,SIZEDTEXT *st,TEXTARGS *ta);
void pstringorlist (STRINGLIST *s);
void pstringlist (STRINGLIST *s);
void psizedtext (SIZEDTEXT *s);
void ptext (SIZEDTEXT *s);
void pthread (THREADNODE *thr);
void pcapability (long flag);
long nameok (char *ref,char *name);
char *bboardname (char *cmd,char *name);
char *imap_responder (void *challenge,unsigned long clen,unsigned long *rlen);
long proxycopy (MAILSTREAM *stream,char *sequence,char *mailbox,long options);
long proxy_append (MAILSTREAM *stream,void *data,char **flags,char **date,
		   STRING **message);
long append_msg (MAILSTREAM *stream,void *data,char **flags,char **date,
		 STRING **message);
void mm_list_work (char *what,int delimiter,char *name,long attributes);
char *lasterror (void);

/* Global storage */

char *version = "2000.282";	/* version number of this server */
time_t alerttime = 0;		/* time of last alert */
time_t sysalerttime = 0;	/* time of last system alert */
time_t useralerttime = 0;	/* time of last user alert */
time_t lastcheck = 0;		/* time of last checkpoint */
int state = LOGIN;		/* server state */
int cancelled = NIL;		/* authenticate cancelled */
int trycreate = 0;		/* saw a trycreate */
int finding = NIL;		/* doing old FIND command */
int anonymous = 0;		/* non-zero if anonymous */
int critical = NIL;		/* non-zero if in critical code */
int quell_events = NIL;		/* non-zero if in FETCH response */
int existsquelled = NIL;	/* non-zero if an EXISTS was quelled */
MAILSTREAM *stream = NIL;	/* mailbox stream */
DRIVER *curdriver = NIL;	/* note current driver */
MAILSTREAM *tstream = NIL;	/* temporary mailbox stream */
unsigned long nmsgs =0xffffffff;/* last reported # of messages and recent */
unsigned long recent = 0xffffffff;
char *user = NIL;		/* user name */
char *pass = NIL;		/* password */
char cmdbuf[TMPLEN];		/* command buffer */
char *tag;			/* tag portion of command */
char *cmd;			/* command portion of command */
char *arg;			/* pointer to current argument of command */
char *lstwrn = NIL;		/* last warning message from c-client */
char *lsterr = NIL;		/* last error message from c-client */
char *response = NIL;		/* command response */
int litsp = 0;			/* literal stack pointer */
char *litstk[LITSTKLEN];	/* stack to hold literals */
unsigned long lastuid = 0;	/* last fetched uid */
char *lastid = NIL;		/* last fetched body id for this message */
SIZEDTEXT lastst = {NIL,0};	/* last sizedtext */


/* Response texts which appear in multiple places */

char *win = "%.80s OK %.80s completed\015\012";
char *altwin = "%.80s OK %.900s\015\012";
char *lose = "%.80s NO %.80s failed: %.900s\015\012";
char *losetry = "%.80s NO [TRYCREATE] %.80s failed: %.900s\015\012";
char *misarg = "%.80s BAD Missing required argument to %.80s\015\012";
char *badarg = "%.80s BAD Argument given to %.80s when none expected\015\012";
char *badseq = "%.80s BAD Bogus sequence in %.80s\015\012";
char *badatt = "%.80s BAD Bogus attribute list in %.80s\015\012";
char *argrdy = "+ Ready for argument\015\012";


/* Message string driver for message stringstructs */

STRINGDRIVER msg_string = {
  msg_string_init,		/* initialize string structure */
  msg_string_next,		/* get next byte in string structure */
  msg_string_setpos		/* set position in string structure */
};

/* Main program */

int main (int argc,char *argv[])
{
  unsigned long i,j,k,m,uid;
  long f;
  char *s,*t,*u,*v,tmp[MAILTMPLEN];
  struct stat sbuf;
  time_t autologouttime = 0;
#include "linkage.c"
  rfc822_date (tmp);		/* get date/time at startup */
				/* initialize server */
  server_init (argv[0],"imap","imaps","imap",clkint,kodint,hupint,trmint);
				/* forbid automatic untagged expunge */
  mail_parameters (NIL,SET_EXPUNGEATPING,NIL);
				/* arm proxy copy callback */
  mail_parameters (NIL,SET_MAILPROXYCOPY,(void *) proxycopy);
  s = myusername_full (&i);	/* get user name and flags */
  switch (i) {
  case MU_NOTLOGGEDIN:
    PSOUT ("* OK [");		/* not logged in, ordinary startup */
    pcapability (-1);
    break;
  case MU_ANONYMOUS:
    anonymous = T;		/* anonymous user, fall into default */
    s = "ANONYMOUS";
  case MU_LOGGEDIN:
    PSOUT ("* PREAUTH [");	/* already logged in, pre-authorized */
    pcapability (1);
    user = cpystr (s);		/* copy user name */
    pass = cpystr ("*");	/* set fake password */
    state = SELECT;		/* enter select state */
    break;
  default:
    fatal ("Unknown state from myusername_full()");
  }
  PSOUT ("] ");
  PSOUT (tcp_serverhost ());
  PSOUT (" IMAP4rev1 ");
  PSOUT (version);
  PSOUT (" at ");
  PSOUT (tmp);
  CRLF;
  PFLUSH;			/* dump output buffer */
  switch (state) {		/* do this after the banner */
  case LOGIN:
    autologouttime = time (0) + LOGINTIMEOUT;
    break;
  case SELECT:
    syslog (LOG_INFO,"Preauthenticated user=%.80s host=%.80s",
	    user,tcp_clienthost ());
    break;
  }

  do {				/* command processing loop */
    slurp (cmdbuf,TMPLEN);	/* slurp command */
				/* no more last error or literal */
    if (lstwrn) fs_give ((void **) &lstwrn);
    if (lsterr) fs_give ((void **) &lsterr);
    while (litsp) fs_give ((void **) &litstk[--litsp]);
				/* find end of line */
    if (!strchr (cmdbuf,'\012')) {
      if (t = strchr (cmdbuf,' ')) *t = '\0';
      if ((t - cmdbuf) > 100) t = NIL;
      flush ();			/* flush excess */
      if (state == LOGIN)	/* error if NLI */
	syslog (LOG_INFO,"Line too long before authentication host=%.80s",
		tcp_clienthost ());
      sprintf (tmp,response,t ? cmdbuf : "*");
      PSOUT (tmp);
    }
    else if (!(tag = strtok (cmdbuf," \015\012"))) {
      if (state == LOGIN)	/* error if NLI */
	syslog (LOG_INFO,"Null command before authentication host=%.80s",
		tcp_clienthost ());
      PSOUT ("* BAD Null command\015\012");
    }
    else if (strlen (tag) > 50) PSOUT ("* BAD Excessively long tag\015\012");
    else if (!(cmd = strtok (NIL," \015\012"))) {
      if (state == LOGIN)	/* error if NLI */
	syslog (LOG_INFO,"Missing command before authentication host=%.80s",
		tcp_clienthost ());
      PSOUT (tag);
      PSOUT (" BAD Missing command\015\012");
    }
    else {			/* parse command */
      response = win;		/* set default response */
      finding = NIL;		/* no longer FINDing */
      ucase (cmd);		/* canonicalize command case */
				/* UID command? */
      if (!strcmp (cmd,"UID") && strtok (NIL," \015\012")) {
	uid = T;		/* a UID command */
	cmd[3] = ' ';		/* restore the space delimiter */
	ucase (cmd);		/* make sure command all uppercase */
      }
      else uid = NIL;		/* not a UID command */
				/* snarf argument */
      arg = strtok (NIL,"\015\012");

				/* these commands always valid */
      if (!strcmp (cmd,"NOOP")) {
	if (arg) response = badarg;
	else if (stream)	/* allow untagged EXPUNGE */
	  mail_parameters (stream,SET_ONETIMEEXPUNGEATPING,(void *) stream);
      }
      else if (!strcmp (cmd,"LOGOUT")) {
	if (arg) response = badarg;
	else {			/* time to say farewell */
	  server_init (NIL,NIL,NIL,NIL,SIG_IGN,SIG_IGN,SIG_IGN,SIG_IGN);
	  if (state == OPEN) mail_close (stream);
	  state = LOGOUT;
	  stream = NIL;
	  PSOUT ("* BYE ");
	  PSOUT (mylocalhost ());
	  PSOUT (" IMAP4rev1 server terminating connection\015\012");
	}
      }
      else if (!strcmp (cmd,"CAPABILITY")) {
	if (arg) response = badarg;
	else {
	  PSOUT ("* ");
	  pcapability (0);	/* print capabilities */
	  CRLF;
	}
	if (stream)		/* allow untagged EXPUNGE */
	  mail_parameters (stream,SET_ONETIMEEXPUNGEATPING,(void *) stream);
      }