/*-------------------------------------------------------*/
/* util/mailpost.c      ( NTHU CS MapleBBS Ver 2.36 )    */
/*-------------------------------------------------------*/
/* target : (1) general user E-mail post 到看板          */
/*          (2) BM E-mail post 到精華區                  */
/*          (3) 自動審核身份認證信函之回信               */
/* create : 95/03/29                                     */
/* update : 95/12/15                                     */
/*-------------------------------------------------------*/


#include        <stdio.h>
#include        <ctype.h>
#include        <sys/stat.h>
#include        <sys/file.h>
#include        <fcntl.h>
#include        <time.h>


#include        "bbs.h"


char *fn_passwd = ".PASSWDS";
char *crypt();

#define _BBS_UTIL_C_
#include "cache.c"
#include "record.c"

userec record;
char myfrom[128], mysub[128], myname[128], mypasswd[128], myboard[128], mytitle[128], mydigest[128];

#define JUNK            0
#define NET_SAVE        1
#define LOCAL_SAVE      2

int mymode = JUNK;


#define LOG_FILE        "etc/mailog"


/* ----------------------------------------------------- */
/* buffered I/O for stdin                                */
/* ----------------------------------------------------- */


#define POOL_SIZE       8192
#define LINE_SIZE       512

char pool[POOL_SIZE];
char mybuf[LINE_SIZE];
int pool_size = POOL_SIZE;
int pool_ptr = POOL_SIZE;


int
readline(buf)
  char *buf;
{
  register char ch;
  register int len, bytes;

  len = bytes = 0;
  do
  {
    if (pool_ptr >= pool_size)
    {
      if (pool_size = fread(pool, 1, POOL_SIZE, stdin))
        pool_ptr = 0;
      else
        break;
    }
    ch = pool[pool_ptr++];
    bytes++;

    if (ch == '\r')
      continue;

    buf[len++] = ch;
  } while (ch != '\n' && len < (LINE_SIZE - 1));

  buf[len] = '\0';
  return bytes;
}


/* ----------------------------------------------------- */
/* record etc/mailog for management                      */
/* ----------------------------------------------------- */

void
mailog(mode, msg)
  char *mode, *msg;
{
  FILE *fp;

  if (fp = fopen(LOG_FILE, "a"))
  {
    time_t now;
    struct tm *p;

    time(&now);
    p = localtime(&now);
    fprintf(fp, "%02d/%02d/%02d %02d:%02d:%02d <%s> %s\n",
      p->tm_year, p->tm_mon + 1, p->tm_mday, p->tm_hour, p->tm_min, p->tm_sec,
      mode, msg);
    fclose(fp);
  }
}


void
str_lower(t, s)
  char *t, *s;
{
  register uschar ch;

  do
  {
    ch = *s++;
    *t++ = (ch >= 'A' && ch <= 'Z') ? ch | 32 : ch;
  } while (ch);
}



int
valid_ident(ident)
  char *ident;
{
  static char *invalid[] = {"unknown@", "root@", "gopher@", "bbs@",
  "@bbs", "guest@", "@ppp", "@slip", NULL};
  char buf[128];
  int i;

  str_lower(buf, ident);
  for (i = 0; invalid[i]; i++)
    if (strstr(buf, invalid[i]))
      return 0;
  return 1;
}


int
get_userec(usrnum, record)
  int usrnum;
  userec *record;
{
  int fh;

  if ((fh = open(fn_passwd, O_RDWR)) == -1)
  {
    printf(":Err: unable to open %s file.\n", fn_passwd);
  }
  else
  {
    lseek(fh, (usrnum - 1) * sizeof(userec), SEEK_SET);
    read(fh, record, sizeof(userec));
  }
  return fh;
}


/* ------------------------------------------------------- */
/* 記錄驗證資料：user 有可能正在線上，所以寫入檔案以保周全 */
/* ------------------------------------------------------- */


void
justify_user()
{
  FILE *fp;
  char buf[80];

  sprintf(buf, "home/%s/email", record.userid);

  if (fp = fopen(buf, "w"))
  {
    fprintf(fp, "%s\n", myfrom);
    fclose(fp);
  }
  strncpy(record.justify, myfrom, 43);
  record.userlevel |= PERM_LOGINOK;
}


void
verify_user(magic)
  char *magic;
{
  char *ptr, *next, ch;
  ushort checksum, usrnum;
  int fh;

  if (ptr = (char *) strchr(magic, '('))
  {
    *ptr++ = '\0';
    if (next = (char *) strchr(ptr, ':'))
    {
      *next++ = '\0';
      usrnum = atoi(ptr) - MAGIC_KEY;
      if (ptr = (char *) strchr(next, ')'))
      {
        *ptr++ = '\0';
        checksum = atoi(next);

        if ((fh = get_userec(usrnum, &record)) == -1)
          return;

        if (!ci_strcmp(magic, record.userid))
        {
          ptr = myfrom;         /* record.email; */
          while (ch = *ptr++)
          {
            if (ch <= ' ')
              break;
            if (ch >= 'A' && ch <= 'Z')
              ch |= 0x20;
            usrnum = (usrnum << 1) ^ ch;
          }
          if ((usrnum == checksum) && valid_ident(myfrom))
          {
            justify_user();
            lseek(fh, -(sizeof record), SEEK_CUR);
            write(fh, &record, sizeof record);
            sprintf(mybuf, "[%s]%s", record.userid, myfrom);
            mailog("verify", mybuf);
          }
        }
        close(fh);
      }
    }
  }
}


int
post_article()
{
  fileheader header;
  char index[64], fpath[80];
  FILE *fidx;
  struct stat st;

  sprintf(fpath, "boards/%s", mymode ? myboard : "junk");
  sprintf(index, "%s/.DIR", fpath);

  if (mymode == JUNK)
  {
    pool_ptr = 0;
    if (!readline(mybuf))
      exit(0);

    if (!*myname)
      strcpy(myname, "系統備忘錄");
    if (!*mytitle)
      strcpy(mytitle, *mysub ? mysub : "[原信照登]");
  }
  else
  {
    char msgbuf[256];

    sprintf(msgbuf, "[%s]%s => %s", record.userid, myfrom, myboard);
    mailog("mailpost", msgbuf);
  }

#ifdef  VERBOSE
  if (stat(fpath, &st) == -1)
  {
    if (mkdir(fpath, 0755) == -1)
    {
      printf("board dir create error\n");
      return -1;
    }
  }
  else if (!(st.st_mode & S_IFDIR))
  {
    printf("board dir error\n");
    return -1;
  }

  printf("dir: %s\n", fpath);
#endif

  stampfile(fpath, &header);
  fidx = fopen(fpath, "w");

  printf("post to %s\n", fpath);

  if (mymode)
  {
    time_t now = time(NULL);

    fprintf(fidx, "作者: %s (%s) %s: %s\n標題: %s\n時間: %s\n",
      myname, record.username, (mymode == LOCAL_SAVE ? "站內" : "看板"),
      myboard, mytitle, ctime(&now));

    if (mymode == LOCAL_SAVE)
    {
      header.savemode = 'L';    /* local article */
      header.filemode = FILE_LOCAL;
    }
    else
      header.savemode = 'S';    /* 須轉信 */
  }

  do
  {
    fputs(mybuf, fidx);
  } while (readline(mybuf));
  fclose(fidx);

  strncpy(header.owner, myname, IDLEN);
  strncpy(header.title, mytitle, TTLEN);
  append_record(index, &header, sizeof(header));

  if ((mymode == NET_SAVE) && (fidx = fopen("innd/out.bntp", "a")))
  {
    fprintf(fidx, "%s\t%s\t%s\t%s\t%s\n",
      myboard, header.filename, myname, record.username, mytitle);
    fclose(fidx);
  }
  return 0;
}


int
digest_article()
{
  char *str_mandex = "/.Names";
  char index[256], mpath[80], *ptr, ch;
  FILE *fh;
  time_t now;
  struct tm *ptime;

  sprintf(mybuf, "[%s]%s => %s", record.userid, myfrom, myboard);
  mailog("digest", mybuf);

  sprintf(mpath, "man/%s", myboard);
  sprintf(index, "%s%s", mpath, str_mandex);
  if (!(fh = fopen(index, "r")))
  {
    printf(":Err: Unable to digest in %s.\n", myboard);
    return -1;
  }

  ch = 1;
  while (fgets(index, 256, fh))
  {
    if (!strncmp(index, "# Title=", 8))
    {
      ch = 0;
      break;
    }
  }
  fclose(fh);

  if (ch)
    return -1;

  if (ptr = (char *) strstr(index, myname))
  {
    ch = ptr[-1];
    if ((ch == '[') || (ch == '/'))
    {
      ch = ptr[strlen(myname)];
      if ((ch == ']') || (ch == '/'))
      {
        /* truncate long lines */

        mydigest[79] = mytitle[62] = '\0';
        if (ptr = (char *) strchr(mydigest, ' '))
          *ptr = '\0';

        sprintf(index, "%s/%s", mpath, mydigest);
        if (fh = fopen(index, "a+"))
        {
          printf("digest: %s\n", index);

          do
          {
            fputs(mybuf, fh);
          } while (readline(mybuf));
          fclose(fh);

          now = time(NULL);
          ptime = localtime(&now);
          ptr = (char *) strrchr(index, '/');
          strcpy(mydigest, ptr + 1);
          strcpy(ptr, str_mandex);
          fh = fopen(index, "a+");
          fprintf(fh, "Name=◇ %s\nDate=%02d/%02d/%02d\nPath=%s\n\n",
            mytitle, ptime->tm_mon + 1, ptime->tm_mday, ptime->tm_year, mydigest);
          fclose(fh);
          return 0;
        }
      }
    }
  }
  return -1;
}


int
mailpost()
{
  int uid, fh, dirty;
  char *ip, *ptr;
  char *token, *key;

  /* parse header */

  readline(mybuf);
  if (strncasecmp(mybuf, "From", 4))
    return post_article();      /* junk */

  dirty = *myfrom = *mysub = *myname = *mypasswd = *myboard = *mytitle = *mydigest = 0;

  while (!*myname || !*mypasswd || !*myboard || !*mytitle)
  {
    if (mybuf[0] == '#')
    {
      key = mybuf + 1;

      /* skip trailing space */

      if (ptr = strchr(key, '\n'))
      {
        do
        {
          *ptr = '\0';
          fh = *(--ptr);
        } while (fh == ' ' || fh == '\t');
      }

      /* split token & skip leading space */

      if (token = strchr(key, ':'))
      {
        *token = '\0';
        do
        {
          fh = *(++token);
        } while (fh == ' ' || fh == '\t');
      }

      if (!ci_strcmp(key, "name"))
      {
        strcpy(myname, token);
      }
      else if (!ci_strcmp(key, "passwd") || !ci_strcmp(key, "password") || !ci_strcmp(key, "passward"))
      {
        strcpy(mypasswd, token);
      }
      else if (!ci_strcmp(key, "board"))
      {
        strcpy(myboard, token);
      }
      else if (!ci_strcmp(key, "title") || !ci_strcmp(key, "subject"))
      {
        strcpy(mytitle, token);
      }
      else if (!ci_strcmp(key, "digest"))
      {
        strcpy(mydigest, token);
      }
      else if (!ci_strcmp(key, "local"))
      {
        mymode = LOCAL_SAVE;
      }
    }
    else if (!strncasecmp(mybuf, "From", 4))
    {
      str_lower(myfrom, mybuf + 4);
      if (strstr(myfrom, "mailer-daemon"))
        return post_article();

      if ((ip = strchr(mybuf, '<')) && (ptr = strrchr(ip, '>')))
      {
        *ptr = '\0';
        if (ip[-1] == ' ')
          ip[-1] = '\0';
        ptr = (char *) strchr(mybuf, ' ');
        while (*++ptr == ' ');
        sprintf(myfrom, "%s (%s)", ip + 1, ptr);
      }
      else
      {
        strtok(mybuf, " ");
        strcpy(myfrom, (char *) strtok(NULL, " "));
      }
    }
    else if (!strncmp(mybuf, "Subject: ", 9))
    {
      /* audit justify mail */

      if (ptr = strstr(mybuf, "[MapleBBS]To "))
      {
        verify_user(ptr + 13);
        return -1;
      }
      if (ptr = strstr(mybuf, "[MapleBridge]To "))
      {
        verify_user(ptr + 16);
        return -1;
      }
      if (ptr = strchr(token = mybuf + 9, '\n'))
        *ptr = '\0';
      strcpy(mysub, token);
    }

    if ((++dirty > 50) || !readline(mybuf))
    {
      mymode = JUNK;
      return post_article();    /* junk */
    }
  }

  dirty = 0;

  /* check if the userid is in our bbs now */
  if (!(uid = searchuser(myname)))
  {
    printf("BBS user <%s> not existed\n", myname);
    return -1;
  }

  if ((fh = get_userec(uid, &record)) == -1)
  {
    return -1;
  }

  /* check password */

  key = crypt(mypasswd, record.passwd);
  if (strcmp(key, record.passwd))
  {
    printf(":Err: user [%s] password incorrect!\n", myname);
    close(fh);
    return -1;
  }

  if (valid_ident(myfrom))
  {

    /* ------------------------------ */
    /* 順便記錄 user's E-mail address */
    /* ------------------------------ */

    justify_user();
    dirty = YEA;
  }

  /* check permission */

  if (!*mydigest)
  {
    if (mymode != LOCAL_SAVE)
      mymode = NET_SAVE;

    if (!strstr(myboard, "test"))
    {
      record.numposts++;
      dirty = YEA;
    }
  }

  while (mybuf[0] && mybuf[0] != '\n')
    readline(mybuf);

  while (mybuf[0] == '\n')
    readline(mybuf);

  if (dirty && mybuf[0])
  {
    lseek(fh, -sizeof(struct userec), SEEK_CUR);
    write(fh, &record, sizeof(struct userec));
  }
  close(fh);

  if (mybuf[0])
    return (*mydigest) ? digest_article() : post_article();

  mymode = JUNK;
  return post_article();
}


void
main(void)
{
  chdir(BBSHOME);
  if (mailpost())
  {
    /* eat mail queue */
    while (fread(pool, 1, POOL_SIZE, stdin));
  }
  exit(0);
}