vdelivermail.c

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 */
int deliver_mail(char *address, char *quota)
{
 time_t tm;
 off_t file_count;
 long unsigned pid;
 long unsigned inject_pid = 0;
 int child;
 int write_fd;
 FILE *fs;
 char tmp_file[256];

    /* This is a comment, ignore it */
    if ( *address == '#' ) return(0);

    /* check if the email is looping to this user */
    if ( is_looping( address ) == 1 ) {
        printf("message is looping %s\n", address );
        return(-3);
    }
    
#ifdef MAKE_SEEKABLE
    /* at this point we know the message size - if its 0 drop out silently */
    if (message_size==0)
        return(0);
#endif

    /* This is an command */
    if ( *address == '|' ) { 

        /* run the command */ 
        run_command(address);
        return(0);
      }

    /* Starts with '.' or '/', then it's an mbox or maildir delivery */
    else if ((*address == '.') || (*address == '/')) {
        /* check for mbox delivery and exit accordingly */
        if (address[strlen(address)-1] != '/') {
            printf ("can't handle mbox delivery for %s", address);
            vexit(111);
        }

        /* if the user has a quota set */
        if ( strncmp(quota, "NOQUOTA", 2) != 0 ) {

            /* If the user is over their quota, return it back
             * to the sender.
             */
            if (user_over_maildirquota(address,format_maildirquota(quota))==1) {

                /* check for over quota message in domain */
                sprintf(tmp_file, "%s/.over-quota.msg",TheDomainDir);
                if ( (fs=fopen(tmp_file, "r")) == NULL ) {
                    /* if no domain over quota then check in vpopmail dir */
                    sprintf(tmp_file, "%s/domains/.over-quota.msg",VPOPMAILDIR);
                    fs=fopen(tmp_file, "r");
                }

                if ( fs == NULL ) {
                    printf("user is over quota\n");
                } else {
                    while( fgets( tmp_file, 256, fs ) != NULL ) {
                        fputs(tmp_file, stdout);
                    }
                    fclose(fs);
                }
                deliver_quota_warning(address, format_maildirquota(quota));
                return(-1);
            }
            if (QUOTA_WARN_PERCENT >= 0 &&
                vmaildir_readquota(address, format_maildirquota(quota))
                    >= QUOTA_WARN_PERCENT) {
                deliver_quota_warning(address, format_maildirquota(quota));
            }
        }

#ifdef DOMAIN_QUOTAS
	/* bk: check domain quota */
        if (domain_over_maildirquota(address)==1)
        {
            /* check for over quota message in domain */
            sprintf(tmp_file, "%s/.over-quota.msg",TheDomainDir);
            if ( (fs=fopen(tmp_file, "r")) == NULL ) {
                /* if no domain over quota then check in vpopmail dir */
                sprintf(tmp_file, "%s/domains/.over-quota.msg",VPOPMAILDIR);
                fs=fopen(tmp_file, "r");
            }

            if ( fs == NULL ) {
                printf("domain is over quota\n");
            } else {
                while( fgets( tmp_file, 256, fs ) != NULL ) {
                    fputs(tmp_file, stdout);
                }
                fclose(fs);
            }
            deliver_quota_warning(address, format_maildirquota(quota));
            return(-1);
        }
#endif

        /* Format the email file name */
        gethostname(hostname,sizeof(hostname));
        pid=getpid();
        time (&tm);
        snprintf(local_file, 156, "%stmp/%lu.%lu.%s,S=%lu",
            address,(long unsigned)tm,(long unsigned)pid,
            hostname, (long unsigned)message_size);
        snprintf(local_file_new, 156, "%snew/%lu.%lu.%s,S=%lu",
            address,(long unsigned)tm,(long unsigned)pid,hostname, 
        (long unsigned)message_size);

        /* open the new email file */
        if ((write_fd=open(local_file,O_CREAT|O_RDWR,S_IRUSR|S_IWUSR))== -1) {
            printf("can not open new email file errno=%d file=%s\n", 
                errno, local_file);
            return(-2);
        }
 
        /* Set the Delivered-To: header */
        if ( strcmp( address, bounce) == 0 ) {
            snprintf(DeliveredTo, sizeof(DeliveredTo), 
                "%sDelivered-To: %s@%s\n", getenv("RPLINE"), 
                 TheUser, TheDomain);
        } else {
        
            snprintf(DeliveredTo, sizeof(DeliveredTo), 
                "%sDelivered-To: %s\n", getenv("RPLINE"), 
                maildir_to_email(address));
        }

    /* must be an email address */
    } else {
      char *dtline;
      char *atpos;
      int dtlen;

      inject_pid = qmail_inject_open(address);
      write_fd = fdm;

      /* use the DTLINE variable, but skip past the dash in 
       * domain-user@domain 
       */

      if ( (dtline = getenv("DTLINE")) != NULL ) {
        dtlen = strlen(dtline);
        /* make sure dtline is at least as long as "Delivered-To: " */
        if (dtlen < 15) {
          dtline = NULL;
        } else {
          dtline += 14;  /* skip "Delivered-To: " */
          dtlen -= 14;
          atpos = strchr (dtline, '@');
          /* ex: dtline = "[e-mail]\n"
           * dtlen = 25, atpos = dtline+14
           * add 25 - 14 - 1 = 10 bytes to dtline,
           * now points to "[e-mail]\n".
           */
          if (atpos != NULL) {
            dtline += (dtlen - (atpos - dtline) - 1);
          }
        }
      }
      if (dtline == NULL) {
        if (*address=='&') ++address;  /* will this case ever happen? */
        snprintf(DeliveredTo, sizeof(DeliveredTo), 
          "%sDelivered-To: %s\n", getenv("RPLINE"), address);
      } else {
        snprintf(DeliveredTo, sizeof(DeliveredTo), 
          "%sDelivered-To: %s", getenv("RPLINE"), dtline);
      }
    }

#ifdef MAKE_SEEKABLE
    if (!Seekable(0))
        MakeSeekable(stdin);
#endif

    if ( lseek(0, 0L, SEEK_SET) < 0 ) {
        printf("lseek errno=%d\n", errno);
        return(-2);
    }

    /* write the Return-Path: and Delivered-To: headers */
    if (write(write_fd,DeliveredTo,strlen(DeliveredTo))!= 
              strlen(DeliveredTo)) {

        close(write_fd);
        /* Check if the user is over quota */
        if ( errno == EDQUOT ) {
            return(-1);
        } else {
            printf("failed to write delivered to line errno=%d\n",errno);
           return(-2);
        }
    }


    /* read it in chunks and write it to the new file */
    while((file_count=read(0,msgbuf,MSG_BUF_SIZE))>0) {
        if ( write(write_fd,msgbuf,file_count) == -1 ) {
            close(write_fd);

            /* if the write fails and we are writing to a Maildir
             * then unlink the file
             */
            if ( unlink(local_file) != 0 ) {
                printf("unlink failed %s errno = %d\n", local_file, errno);
                return(-2);
            }

            /* Check if the user is over quota */
            if ( errno == EDQUOT ) {
                return(-1);
            } else {
                printf("write failed errno = %d\n", errno);
                return(-2);
            }
        }
    }
    if ( inject_pid != 0 ) {
        close(write_fd);
        waitpid(inject_pid,&child,0);
        return(wait_exitcode(child));
    }

    /* if we are writing to a Maildir, move it
     * into the new directory
     */

    /* sync the data to disk and close the file */
    errno = 0;
    if ( 
#ifdef FILE_SYNC
#ifdef HAVE_FDATASYNC
        fdatasync(write_fd) == 0 &&
#else
        fsync(write_fd) == 0 &&
#endif
#endif
        close(write_fd) == 0 ) {

        /* if this succeeds link the file to the new directory */
        if ( link( local_file, local_file_new ) == 0 ) {
            if ( unlink(local_file) != 0 ) {
                printf("unlink failed %s errno = %d\n", local_file, errno);
            }
        } else {

            /* coda fs has problems with link, check for that error */
            if ( errno==EXDEV ) {

                /* try to rename the file instead */
                if (rename(local_file, local_file_new)!=0) {

                    /* even rename failed, time to give up */
                    printf("rename failed %s %s errno = %d\n", 
                        local_file, local_file_new, errno);
                    /* shouldn't we unlink the file here? */
                    return(-2);

                /* rename worked, so we are okay now */
                } else {
                    errno = 0;
                }

            /* link failed and we are not on coda */
            } else {
                printf("link REALLY failed %s %s errno = %d\n", 
                    local_file, local_file_new, errno);
                unlink(local_file);
                return(-2);
            }
        }
    }

    /* return success */
    return(0);
}

/* Check if the vpopmail user has a .qmail file in thier directory
 * and foward to each email address, Maildir or program 
 *  that is found there in that file
 *
 * Return: 1 if we found and delivered email
 *       : 0 if not found
 *       : -1 if no user .qmail file 
 *
 */
int check_forward_deliver(char *dir)
{
 static char qmail_line[500];
 char tmpbuf[500];
 FILE *fs;
 int i;
 int return_value = 0;
 int deliver_err;
   
    chdir(dir);

    /* format the file name */
    if ( (fs = fopen(".qmail","r")) == NULL ) {

        /* no file, so just return */
        return(-1);
    }

    /* format a simple loop checker name */
    snprintf(tmpbuf, 500, "%s@%s", TheUser, TheDomain);

    /* read the file, line by line */
    while ( fgets(qmail_line, 500, fs ) != NULL ) {
        if (*qmail_line == '#') continue;

        /* remove the trailing new line */
        for(i=0;qmail_line[i]!=0;++i) {
            if (qmail_line[i] == '\n') qmail_line[i] = 0;
        }

        /* simple loop check, if they are sending it to themselves
         * then skip this line
         */
        if ( strcmp( qmail_line, tmpbuf) == 0 ) continue;
        /* check for &[e-mail] as well */
        if ((*qmail_line == '&') && (strcmp (qmail_line + 1, tmpbuf) == 0))
            continue;

        deliver_err = deliver_mail(qmail_line, "NOQUOTA");
        if (deliver_err == -2) {
            printf("system error\n");
            vexit(111);
        } else if (deliver_err == -3) {
            printf("mail is looping\n");
            vexit(111);
        }
        return_value = 1;
    }

    /* close the file */
    fclose(fs);

    /* return if we found one or not */
    return(return_value);
}

void sig_catch(sig,f)
int sig;
void (*f)();
{
#ifdef HAVE_SIGACTION
  struct sigaction sa;
  sa.sa_handler = f;
  sa.sa_flags = 0;
  sigemptyset(&sa.sa_mask);
  sigaction(sig,&sa,(struct sigaction *) 0);
#else
  signal(sig,f); /* won't work under System V, even nowadays---dorks */
#endif
}


/* open a pipe to a command 
 * return the pid or -1 if error
 */
void run_command(char *prog)
{
 int child;
 char *(args[4]);
 int wstat;

 while (*prog==' ') ++prog;
 while (*prog=='|') ++prog;

#ifdef MAKE_SEEKABLE
    if (!Seekable(0))
        MakeSeekable(stdin);
#endif

    if ( lseek(0, 0L, SEEK_SET) < 0 ) {
        printf("lseek errno=%d\n", errno);
        return;
    }

 switch(child = fork())
  {
   case -1:
     printf("unable to fork\n"); 
     exit(0);
   case 0:
     args[0] = "/bin/sh"; args[1] = "-c"; args[2] = prog; args[3] = 0;
     sig_catch(SIGPIPE,SIG_DFL);
     execv(*args,args);
     printf("Unable to run /bin/sh: ");
     exit(-1);
  }

  wait(&wstat);
  waitpid(wstat,&child,0);
  switch(wait_exitcode(wstat))
   {
    case 64: case 65: case 70: case 76: case 77: case 78: case 100: case 112: _exit(100);
    case 99: _exit(99);
    case 0: break;
    default: _exit(111);
   }

}

/* Check for a looping message
 * This is done by checking for a matching line
 * in the email headers for Delivered-To: which
 * we put in each email
 * 
 * Return 1 if looping
 * Return 0 if not looping
 * Return -1 on error 
 */
int is_looping( char *address ) 
{
 int i;
 int found;
 char *dtline;

    /* if we don't know the message size then get it */
    if ( message_size == 0 ) {
        /* read the message to get the size */
        message_size = get_message_size();
    }
    if (*address=='&') ++address;

    /* check the DTLINE */
    dtline = getenv("DTLINE");
    if ( dtline != NULL && is_loop_match(dtline, address) == 1 ) {
      return(1);