mpp.c

/*
 * $Id$
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>
#include <ctype.h>
#include <string.h>

#include "mailer_config.h"

char *arpadate(char *);

/* mpp msgfile outfile hostname */
int main(int argc, char *argv[])
{
    FILE *f,*o;
    struct stat sbuf;
    char line[MAX_LINE_LEN+1];
    char *message,*p;
    char *longdate;
    char from_addr[MAX_ADDR_LEN + 1];
    char *user,*host;
    time_t utime;
    struct tm *ltime;
    int hdr,reqhdr;
#if defined(USE_IDTAGS)
    char idtag[MAX_ADDR_LEN+40];
    char body_idtag[MAX_ADDR_LEN+40];
#endif /* USE_IDTAGS */

    if(argc != 4)
    {
	fprintf(stderr,"Usage: mpp msgfile tmpfile from_addr\n");
	exit(1);
    }

    if(stat(argv[1],&sbuf)==-1)
    {
	perror("stat (message)");
	exit(1);
    }

    if(!(message=malloc((sbuf.st_size*2)+512)))
    {
	perror("malloc (message)");
	exit(1);
    }

    if(!(f=fopen(argv[1],"r")))
    {
	perror("fopen (message)");
	exit(1);
    }

    if(!(o=fopen(argv[2],"w")))
    {
	perror("fopen (temp file)");
	exit(1);
    }

    /* break from_addr into user@host */
    strcpy(from_addr, argv[3]);
    host=rindex(from_addr,'@');
    if(host == (char *) NULL) {
	fprintf(stderr,"Couldn't parse %s into user@host\n",from_addr);
	exit(1);
    }
    *host='\0';
    ++host;
    user=from_addr;

    p=message;

#define H_FROM	1
#define H_TO	2
#define H_SUBJ	4
#define H_REQ	(H_FROM|H_TO|H_SUBJ)

    hdr=1;
    reqhdr=0;

    /* per RFC822 4.1: preferred order of headers is: "Return-Path",
     * "Received", "Date", "From", "Subject", "Sender", "To"
     */

    longdate=arpadate(NULL);
    utime=time(NULL);
    ltime = localtime(&utime);

#if defined(USE_IDTAGS)
    /* make the ID tags (used in message ID, optionally from and body)
     * be careful about changing these (see do_list.c)
     */

    sprintf(idtag,"%s.%04d%02d%02d.%c%s.%d", HEADER_HEADER,
	    ltime->tm_year+1900, ltime->tm_mon+1, ltime->tm_mday,
	    '\xff',"00000.000", (int) utime);

    /* short/reshuffled version of idtag, embedded in the body */
    sprintf(body_idtag,"%c%s%1d", 
	     '\xff',"00000", ltime->tm_wday);
#endif /* USE_IDTAGS */

    /* received header */
    sprintf(p,"Received: from local (localhost)\r\n"
	    "\tby %s (mailer 1.10) with SMTP", host);
    p+=strlen(p);
#if defined(USE_IDTAGS) && defined(TWEAK_RCVHDR)
    sprintf(p," id <%s>", idtag);
    p+=strlen(p);
#endif
    sprintf(p,";\r\n\t%s\r\n",longdate);
    p+=strlen(p);
    sprintf(p,"Date: %s\r\n",longdate);
    p+=strlen(p);

    /* Message-Id: */
#if defined(USE_IDTAGS) && defined(TWEAK_MSGID)
    sprintf(p,"Message-Id: <%s@%s>\r\n",idtag,host);
#else
    sprintf(p,"Message-Id: <%s.%d@%s>\r\n",HEADER_HEADER,
	    (int)time(NULL),host);
#endif

    p+=strlen(p);

    while(fgets(line,MAX_LINE_LEN+1,f))
    {
	int l;

	l=strlen(line);

	while(l>0 && (line[l-1] == '\n' || line[l-1] == '\r'))
	    line[--l]='\0';

	if(l > MAX_LINE_LEN-2)
	{
	    fprintf(stderr, "Warning: line too long (>%d characters) in "
		    "message, truncated.\n", MAX_LINE_LEN);
	}

	if(l==0 && hdr) {	/* blank line, end of headers */
	    hdr=0;

	    if(reqhdr != H_REQ)
	    {
		fprintf(stderr,
			"Missing required header(s) from message: %s%s%s\n",
			(reqhdr & H_FROM) ? "" : "From: ",
			(reqhdr & H_TO) ? "" : "To: ",
			(reqhdr & H_SUBJ) ? "" : "Subject: ");

		exit(1);
	    }
	}

	/* Add cr/lf */

	line[l++]='\r'; line[l++]='\n'; line[l]='\0';

	if(hdr)
	{
	    char *t;
	    int i,tl,upcase,discard,newhdr;

	    if(!(t=strchr(line,':')))
	    {
		fprintf(stderr,"Bad header: %s",line);
		exit(1);
	    }
	    tl=t-line;

	    upcase=1;
	    line[0]=toupper(line[0]);
	    for(i=0;i<tl;++i)
	    { 
		line[i]=(upcase ? toupper (line[i])
			 : tolower(line[i]));

		upcase=(line[i]=='-');
	    }

	    discard=newhdr=0;

	    if(!strncmp(line,"From: ",tl))		    newhdr = H_FROM;
	    else if(!strncmp(line,"To: ",tl))		    newhdr = H_TO;
	    else if(!strncmp(line,"Subject: ",tl))	    newhdr = H_SUBJ;
	    else if(!strncmp(line,"Date: ",tl))		    discard = 1;
	    else if(!strncasecmp(line,"Message-Id: ",tl))   discard = 1;

	    if((reqhdr & newhdr) || discard)
	    {
		fprintf(stderr,"Warning: discarding extra header: %s",line);			continue;
	    }

#if defined(USE_IDTAGS) && defined(TWEAK_FROMADDR)
	    if(newhdr == H_FROM) {
		char *aptr;
		aptr=index(line,'<');
		if(aptr == (char *) NULL) {
		    aptr=index(line,'\r');
		} else {
		    --aptr;
		}
		/* be careful that this looks like the message-id
		 * above!
		 */
		sprintf(aptr," <%s+%s@%s>\r\n", user, idtag, host);
	    }
#endif

	    reqhdr |= newhdr;
	}

	if(line[0]=='.') { *p='.'; ++p; }
	sprintf(p,"%s",line);
	p+=strlen(p);
    }

#if defined(USE_IDTAGS) && defined(TWEAK_BODY)
    /* add this at the end of the message.  We'll strip it out later (in
     * deliver() if we don't want it.
     */

    sprintf(p,"<%s>\r\n",body_idtag);
    p+=strlen(p);
#endif

    /* EOM sentinel.  Don't change this without looking at deliver.c */
    sprintf(p-2,"\r\n.\r\n");
    p+=strlen(p);

    fprintf(o,"%s",message);
    fclose(o);
    fclose(f);
    return 0;
}