/* * Program: MMDF mail routines * * Author: Mark Crispin * Networks and Distributed Computing * Computing & Communications * University of Washington * Administration Building, AG-44 * Seattle, WA 98195 * Internet: MRC@CAC.Washington.EDU * * Date: 15 May 1993 * Last Edited: 22 October 1998 * * Copyright 1998 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. * */ /* Supposedly, this page has everything the MMDF driver needs to know about * the MMDF delimiter. By changing these macros, the MMDF driver should * change with it. Note that if you change the length of MMDFHDRTXT you * also need to change the ISMMDF and RETIFMMDFWRD macros to reflect the new * size. */ /* Useful MMDF constants */ #define MMDFCHR '\01' /* MMDF character */ #define MMDFCHRS 0x01010101 /* MMDF header character spread in a word */ /* MMDF header text */ #define MMDFHDRTXT "\01\01\01\01\n" /* length of MMDF header text */ #define MMDFHDRLEN (sizeof (MMDFHDRTXT) - 1) /* Validate MMDF header * Accepts: pointer to candidate string to validate as an MMDF header * Returns: T if valid; else NIL */ #define ISMMDF(s) \ ((*(s) == MMDFCHR) && ((s)[1] == MMDFCHR) && ((s)[2] == MMDFCHR) && \ ((s)[3] == MMDFCHR) && ((s)[4] == '\n')) /* Return if a 32-bit word has the start of an MMDF header * Accepts: pointer to word of four bytes to validate as an MMDF header * Returns: pointer to MMDF header, else proceeds */ #define RETIFMMDFWRD(s) { \ if (s[3] == MMDFCHR) { \ if ((s[4] == MMDFCHR) && (s[5] == MMDFCHR) && (s[6] == MMDFCHR) && \ (s[7] == '\n')) return s + 3; \ else if (s[2] == MMDFCHR) { \ if ((s[4] == MMDFCHR) && (s[5] == MMDFCHR) && (s[6] == '\n')) \ return s + 2; \ else if (s[1] == MMDFCHR) { \ if ((s[4] == MMDFCHR) && (s[5] == '\n')) return s + 1; \ else if ((*s == MMDFCHR) && (s[4] == '\n')) return s; \ } \ } \ } \ } /* Validate line * Accepts: pointer to candidate string to validate as a From header * return pointer to end of date/time field * return pointer to offset from t of time (hours of ``mmm dd hh:mm'') * return pointer to offset from t of time zone (if non-zero) * Returns: t,ti,zn set if valid From string, else ti is NIL */ #define VALID(s,x,ti,zn) { \ ti = 0; \ if ((*s == 'F') && (s[1] == 'r') && (s[2] == 'o') && (s[3] == 'm') && \ (s[4] == ' ')) { \ for (x = s + 5; *x && *x != '\n'; x++); \ if (*x) { \ if (x - s >= 41) { \ for (zn = -1; x[zn] != ' '; zn--); \ if ((x[zn-1] == 'm') && (x[zn-2] == 'o') && (x[zn-3] == 'r') && \ (x[zn-4] == 'f') && (x[zn-5] == ' ') && (x[zn-6] == 'e') && \ (x[zn-7] == 't') && (x[zn-8] == 'o') && (x[zn-9] == 'm') && \ (x[zn-10] == 'e') && (x[zn-11] == 'r') && (x[zn-12] == ' '))\ x += zn - 12; \ } \ if (x - s >= 27) { \ if (x[-5] == ' ') { \ if (x[-8] == ':') zn = 0,ti = -5; \ else if (x[-9] == ' ') ti = zn = -9; \ else if ((x[-11] == ' ') && ((x[-10]=='+') || (x[-10]=='-'))) \ ti = zn = -11; \ } \ else if (x[-4] == ' ') { \ if (x[-9] == ' ') zn = -4,ti = -9; \ } \ else if (x[-6] == ' ') { \ if ((x[-11] == ' ') && ((x[-5] == '+') || (x[-5] == '-'))) \ zn = -6,ti = -11; \ } \ if (ti && !((x[ti - 3] == ':') && \ (x[ti -= ((x[ti - 6] == ':') ? 9 : 6)] == ' ') && \ (x[ti - 3] == ' ') && (x[ti - 7] == ' ') && \ (x[ti - 11] == ' '))) ti = 0; \ } \ } \ } \ } /* You are not expected to understand this macro, but read the next page if * you are not faint of heart. * * Known formats to the VALID macro are: * From user Wed Dec 2 05:53 1992 * BSD From user Wed Dec 2 05:53:22 1992 * SysV From user Wed Dec 2 05:53 PST 1992 * rn From user Wed Dec 2 05:53:22 PST 1992 * From user Wed Dec 2 05:53 -0700 1992 * emacs From user Wed Dec 2 05:53:22 -0700 1992 * From user Wed Dec 2 05:53 1992 PST * From user Wed Dec 2 05:53:22 1992 PST * From user Wed Dec 2 05:53 1992 -0700 * Solaris From user Wed Dec 2 05:53:22 1992 -0700 * * Plus all of the above with `` remote from xxx'' after it. Thank you very * much, smail and Solaris, for making my life considerably more complicated. */ /* * What? You want to understand the VALID macro anyway? Alright, since you * insist. Actually, it isn't really all that difficult, provided that you * take it step by step. * * Line 1 Initializes the return ti value to failure (0); * Lines 2-3 Validates that the 1st-5th characters are ``From ''. * Lines 4-5 Validates that there is an end of line and points x at it. * Lines 6-13 First checks to see if the line is at least 41 characters long. * If so, it scans backwards to find the rightmost space. From * that point, it scans backwards to see if the string matches * `` remote from''. If so, it sets x to point to the space at * the start of the string. * Line 14 Makes sure that there are at least 27 characters in the line. * Lines 15-20 Checks if the date/time ends with the year (there is a space * five characters back). If there is a colon three characters * further back, there is no timezone field, so zn is set to 0 * and ti is set in front of the year. Otherwise, there must * either to be a space four characters back for a three-letter * timezone, or a space six characters back followed by a + or - * for a numeric timezone; in either case, zn and ti become the * offset of the space immediately before it. * Lines 21-23 Are the failure case for line 14. If there is a space four * characters back, it is a three-letter timezone; there must be a * space for the year nine characters back. zn is the zone * offset; ti is the offset of the space. * Lines 24-27 Are the failure case for line 20. If there is a space six * characters back, it is a numeric timezone; there must be a * space eleven characters back and a + or - five characters back. * zn is the zone offset; ti is the offset of the space. * Line 28-31 If ti is valid, make sure that the string before ti is of the * form www mmm dd hh:mm or www mmm dd hh:mm:ss, otherwise * invalidate ti. There must be a colon three characters back * and a space six or nine characters back (depending upon * whether or not the character six characters back is a colon). * There must be a space three characters further back (in front * of the day), one seven characters back (in front of the month), * and one eleven characters back (in front of the day of week). * ti is set to be the offset of the space before the time. * * Why a macro? It gets invoked a *lot* in a tight loop. On some of the * newer pipelined machines it is faster being open-coded than it would be if * subroutines are called. * * Why does it scan backwards from the end of the line, instead of doing the * much easier forward scan? There is no deterministic way to parse the * ``user'' field, because it may contain unquoted spaces! Yes, I tested it to * see if unquoted spaces were possible. They are, and I've encountered enough * evil mail to be totally unwilling to trust that ``it will never happen''. */ /* Build parameters */ #define KODRETRY 15 /* kiss-of-death retry in seconds */ #define LOCKTIMEOUT 5 /* lock timeout in minutes */ #define CHUNK 16384 /* read-in chunk size */ /* MMDF I/O stream local data */ typedef struct mmdf_local { unsigned int dirty : 1; /* disk copy needs updating */ int fd; /* mailbox file descriptor */ int ld; /* lock file descriptor */ char *name; /* local file name for recycle case */ char *lname; /* lock file name */ off_t filesize; /* file size parsed */ time_t filetime; /* last file time */ char *buf; /* temporary buffer */ unsigned long buflen; /* current size of temporary buffer */ char *line; /* returned line */ } MMDFLOCAL; /* Convenient access to local data */ #define LOCAL ((MMDFLOCAL *) stream->local) /* Function prototypes */ DRIVER *mmdf_valid (char *name); long mmdf_isvalid (char *name,char *tmp); long mmdf_isvalid_fd (int fd,char *tmp); void *mmdf_parameters (long function,void *value); void mmdf_scan (MAILSTREAM *stream,char *ref,char *pat,char *contents); void mmdf_list (MAILSTREAM *stream,char *ref,char *pat); void mmdf_lsub (MAILSTREAM *stream,char *ref,char *pat); long mmdf_create (MAILSTREAM *stream,char *mailbox); long mmdf_delete (MAILSTREAM *stream,char *mailbox); long mmdf_rename (MAILSTREAM *stream,char *old,char *newname); MAILSTREAM *mmdf_open (MAILSTREAM *stream); void mmdf_close (MAILSTREAM *stream,long options); char *mmdf_header (MAILSTREAM *stream,unsigned long msgno, unsigned long *length,long flags); long mmdf_text (MAILSTREAM *stream,unsigned long msgno,STRING *bs,long flags); char *mmdf_text_work (MAILSTREAM *stream,MESSAGECACHE *elt, unsigned long *length,long flags); void mmdf_flagmsg (MAILSTREAM *stream,MESSAGECACHE *elt); long mmdf_ping (MAILSTREAM *stream); void mmdf_check (MAILSTREAM *stream); void mmdf_check (MAILSTREAM *stream); void mmdf_expunge (MAILSTREAM *stream); long mmdf_copy (MAILSTREAM *stream,char *sequence,char *mailbox,long options); long mmdf_append (MAILSTREAM *stream,char *mailbox,char *flags,char *date, STRING *message); void mmdf_abort (MAILSTREAM *stream); char *mmdf_file (char *dst,char *name); int mmdf_lock (char *file,int flags,int mode,char *lock,int op); void mmdf_unlock (int fd,MAILSTREAM *stream,char *lock); int mmdf_parse (MAILSTREAM *stream,char *lock,int op); char *mmdf_mbxline (MAILSTREAM *stream,STRING *bs,unsigned long *size); unsigned long mmdf_pseudo (MAILSTREAM *stream,char *hdr); unsigned long mmdf_xstatus (MAILSTREAM *stream,char *status,MESSAGECACHE *elt, long flag); long mmdf_rewrite (MAILSTREAM *stream,unsigned long *nexp); long mmdf_write_message (FILE *f,MAILSTREAM *stream,MESSAGECACHE *elt, unsigned long *size); long mmdf_fwrite (FILE *f,char *s,unsigned long i,unsigned long *size); long mmdf_punt_scratch (FILE *f);