rfc822.c

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/* Parse RFC 2822 word
 * Accepts: string pointer
 *	    delimiter (or NIL for phrase word parsing)
 * Returns: pointer to end of word
 */

char *rfc822_parse_word (char *s,const char *delimiters)
{
  char *st,*str;
  if (!s) return NIL;		/* no string */
  rfc822_skipws (&s);		/* flush leading whitespace */
  if (!*s) return NIL;		/* empty string */
  str = s;			/* hunt pointer for strpbrk */
  while (T) {			/* look for delimiter, return if none */
    if (!(st = strpbrk (str,delimiters ? delimiters : wspecials)))
      return str + strlen (str);
				/* ESC in phrase */
    if (!delimiters && (*st == I2C_ESC)) {
      str = ++st;		/* always skip past ESC */
      switch (*st) {		/* special hack for RFC 1468 (ISO-2022-JP) */
      case I2C_MULTI:		/* multi byte sequence */
	switch (*++st) {
	case I2CS_94x94_JIS_OLD:/* old JIS (1978) */
	case I2CS_94x94_JIS_NEW:/* new JIS (1983) */
	  str = ++st;		/* skip past the shift to JIS */
	  while (st = strchr (st,I2C_ESC))
	    if ((*++st == I2C_G0_94) && ((st[1] == I2CS_94_ASCII) ||
					 (st[1] == I2CS_94_JIS_ROMAN) ||
					 (st[1] == I2CS_94_JIS_BUGROM))) {
	      str = st += 2;	/* skip past the shift back to ASCII */
	      break;
	    }
				/* eats entire text if no shift back */
	  if (!st || !*st) return str + strlen (str);
	}
	break;
      case I2C_G0_94:		/* single byte sequence */
	switch (st[1]) {
	case I2CS_94_ASCII:	/* shift to ASCII */
	case I2CS_94_JIS_ROMAN:	/* shift to JIS-Roman */
	case I2CS_94_JIS_BUGROM:/* old buggy definition of JIS-Roman */
	  str = st + 2;		/* skip past the shift */
	  break;
	}
      }
    }

    else switch (*st) {		/* dispatch based on delimiter */
    case '"':			/* quoted string */
				/* look for close quote */
      while (*++st != '"') switch (*st) {
      case '\0':		/* unbalanced quoted string */
	return NIL;		/* sick sick sick */
      case '\\':		/* quoted character */
	if (!*++st) return NIL;	/* skip the next character */
      default:			/* ordinary character */
	break;			/* no special action */
      }
      str = ++st;		/* continue parse */
      break;
    case '\\':			/* quoted character */
      /* This is wrong; a quoted-pair can not be part of a word.  However,
       * domain-literal is parsed as a word and quoted-pairs can be used
       * *there*.  Either way, it's pretty pathological.
       */
      if (st[1]) {		/* not on NUL though... */
	str = st + 2;		/* skip quoted character and go on */
	break;
      }
    default:			/* found a word delimiter */
      return (st == s) ? NIL : st;
    }
  }
}

/* Copy an RFC 2822 format string
 * Accepts: string
 * Returns: copy of string
 */

char *rfc822_cpy (char *src)
{
				/* copy and unquote */
  return rfc822_quote (cpystr (src));
}


/* Unquote an RFC 2822 format string
 * Accepts: string
 * Returns: string
 */

char *rfc822_quote (char *src)
{
  char *ret = src;
  if (strpbrk (src,"\\\"")) {	/* any quoting in string? */
    char *dst = ret;
    while (*src) {		/* copy string */
      if (*src == '\"') src++;	/* skip double quote entirely */
      else {
	if (*src == '\\') src++;/* skip over single quote, copy next always */
	*dst++ = *src++;	/* copy character */
      }
    }
    *dst = '\0';		/* tie off string */
  }
  return ret;			/* return our string */
}


/* Copy address list
 * Accepts: address list
 * Returns: address list
 */

ADDRESS *rfc822_cpy_adr (ADDRESS *adr)
{
  ADDRESS *dadr;
  ADDRESS *ret = NIL;
  ADDRESS *prev = NIL;
  while (adr) {			/* loop while there's still an MAP adr */
    dadr = mail_newaddr ();	/* instantiate a new address */
    if (!ret) ret = dadr;	/* note return */
    if (prev) prev->next = dadr;/* tie on to the end of any previous */
    dadr->personal = cpystr (adr->personal);
    dadr->adl = cpystr (adr->adl);
    dadr->mailbox = cpystr (adr->mailbox);
    dadr->host = cpystr (adr->host);
    prev = dadr;		/* this is now the previous */
    adr = adr->next;		/* go to next address in list */
  }
  return (ret);			/* return the MTP address list */
}

/* Skips RFC 2822 whitespace
 * Accepts: pointer to string pointer
 */

void rfc822_skipws (char **s)
{
  while (T) switch (**s) {
  case ' ': case '\t': case '\015': case '\012':
    ++*s;			/* skip all forms of LWSP */
    break;
  case '(':			/* start of comment */
    if (rfc822_skip_comment (s,(long) NIL)) break;
  default:
    return;			/* end of whitespace */
  }
}


/* Skips RFC 2822 comment
 * Accepts: pointer to string pointer
 *	    trim flag
 * Returns: pointer to first non-blank character of comment
 */

char *rfc822_skip_comment (char **s,long trim)
{
  char *ret,tmp[MAILTMPLEN];
  char *s1 = *s;
  char *t = NIL;
				/* skip past whitespace */
  for (ret = ++s1; *ret == ' '; ret++);
  do switch (*s1) {		/* get character of comment */
  case '(':			/* nested comment? */
    if (!rfc822_skip_comment (&s1,(long) NIL)) return NIL;
    t = --s1;			/* last significant char at end of comment */
    break;
  case ')':			/* end of comment? */
    *s = ++s1;			/* skip past end of comment */
    if (trim) {			/* if level 0, must trim */
      if (t) t[1] = '\0';	/* tie off comment string */
      else *ret = '\0';		/* empty comment */
    }
    return ret;
  case '\\':			/* quote next character? */
    if (*++s1) {		/* next character non-null? */
      t = s1;			/* update last significant character pointer */
      break;			/* all OK */
    }
  case '\0':			/* end of string */
    sprintf (tmp,"Unterminated comment: %.80s",*s);
    MM_LOG (tmp,PARSE);
    **s = '\0';			/* nuke duplicate messages in case reparse */
    return NIL;			/* this is wierd if it happens */
  case ' ':			/* whitespace isn't significant */
    break;
  default:			/* random character */
    t = s1;			/* update last significant character pointer */
    break;
  } while (s1++);
  return NIL;			/* impossible, but pacify lint et al */
}

/* Buffered output routines */


/* Output character to buffer
 * Accepts: buffer
 *	    character to write
 * Returns: T if success, NIL if error
 */

static long rfc822_output_char (RFC822BUFFER *buf,int c)
{
  if ((buf->cur == buf->end) && !rfc822_output_flush (buf)) return NIL;
  *buf->cur++ = c;		/* add character, soutr buffer if full */
  return (buf->cur == buf->end) ? rfc822_output_flush (buf) : LONGT;
}


/* Output data to buffer
 * Accepts: buffer
 *	    data to write
 *	    size of data
 * Returns: T if success, NIL if error
 */

static long rfc822_output_data (RFC822BUFFER *buf,char *string,long len)
{
  while (len) {			/* until request satified */
    long i;
    if (i = min (len,buf->end - buf->cur)) {
      memcpy (buf->cur,string,i);
      buf->cur += i;		/* blat data */
      string += i;
      len -= i;
    }
				/* soutr buffer now if full */
    if ((len || (buf->cur == buf->end)) && !rfc822_output_flush (buf))
      return NIL;
  }
  return LONGT;
}

/* Output string to buffer
 * Accepts: buffer
 *	    string to write
 * Returns: T if success, NIL if error
 */

static long rfc822_output_string (RFC822BUFFER *buf,char *string)
{
  return rfc822_output_data (buf,string,strlen (string));
}


/* Flush buffer
 * Accepts: buffer
 *	    I/O routine
 *	    stream for I/O routine
 * Returns: T if success, NIL if error
 */

long rfc822_output_flush (RFC822BUFFER *buf)
{
  *buf->cur = '\0';		/* tie off buffer at this point */
  return (*buf->f) (buf->s,buf->cur = buf->beg);
}

/* Message writing routines */


/* Output RFC 822 message
 * Accepts: temporary buffer as a SIZEDTEXT
 *	    envelope
 *	    body
 *	    I/O routine
 *	    stream for I/O routine
 *	    non-zero if 8-bit output desired
 * Returns: T if successful, NIL if failure
 *
 * This routine always uses standard specials for phrases and does not write
 * bcc entries, since it is called from the SMTP and NNTP routines.  If you
 * need to do something different you need to arm an rfc822outfull_t and/or
 * rfc822out_t function.
 */

long rfc822_output_full (RFC822BUFFER *buf,ENVELOPE *env,BODY *body,long ok8)
{
  rfc822outfull_t r822of =
    (rfc822outfull_t) mail_parameters (NIL,GET_RFC822OUTPUTFULL,NIL);
  rfc822out_t r822o = (rfc822out_t) mail_parameters (NIL,GET_RFC822OUTPUT,NIL);
				/* call external RFC 2822 output generator */
  if (r822of) return (*r822of) (buf,env,body,ok8);
  else if (r822o) return (*r822o) (buf->cur,env,body,buf->f,buf->s,ok8);
				/* encode body as necessary */
  if (ok8) rfc822_encode_body_8bit (env,body);
  else rfc822_encode_body_7bit (env,body);
				/* output header and body */
  return rfc822_output_header (buf,env,body,NIL,NIL) &&
    rfc822_output_text (buf,body) && rfc822_output_flush (buf);
}

/* Output RFC 822 header
 * Accepts: buffer
 *	    envelope
 *	    body
 *	    non-standard specials to be used for phrases if non-NIL
 *	    flags (non-zero to include bcc
 * Returns: T if success, NIL if failure
 */

long rfc822_output_header (RFC822BUFFER *buf,ENVELOPE *env,BODY *body,
			   const char *specials,long flags)
{
  long i = env->remail ? strlen (env->remail) : 0;
  return			/* write header */
    (!i ||		      /* snip extra CRLF from remail header */
     rfc822_output_data (buf,env->remail,
			 ((i > 4) && (env->remail[i-4] == '\015')) ?
			 i - 2 : i)) &&
    rfc822_output_header_line (buf,"Newsgroups",i,env->newsgroups) &&
    rfc822_output_header_line (buf,"Date",i,env->date) &&
    rfc822_output_address_line (buf,"From",i,env->from,specials) &&
    rfc822_output_address_line (buf,"Sender",i,env->sender,specials) &&
    rfc822_output_address_line (buf,"Reply-To",i,env->reply_to,specials) &&
    rfc822_output_header_line (buf,"Subject",i,env->subject) &&
    ((env->bcc && !(env->to || env->cc)) ?
     rfc822_output_string (buf,"To: undisclosed recipients: ;\015\012") :
     LONGT) &&
    rfc822_output_address_line (buf,"To",i,env->to,specials) &&
    rfc822_output_address_line (buf,"cc",i,env->cc,specials) &&
    (flags ? rfc822_output_address_line (buf,"bcc",i,env->bcc,specials) : T) &&
    rfc822_output_header_line (buf,"In-Reply-To",i,env->in_reply_to) &&
    rfc822_output_header_line (buf,"Message-ID",i,env->message_id) &&
    rfc822_output_header_line (buf,"Followup-to",i,env->followup_to) &&
    rfc822_output_header_line (buf,"References",i,env->references) &&
    (env->remail || !body ||
     (rfc822_output_string (buf,"MIME-Version: 1.0\015\012") &&
      rfc822_output_body_header (buf,body))) &&
				/* write terminating blank line */
    rfc822_output_string (buf,"\015\012");
}

/* Output RFC 2822 header text line
 * Accepts: buffer
 *	    pointer to header type
 *	    non-NIL if resending
 *	    pointer to text
 * Returns: T if success, NIL if failure
 */

long rfc822_output_header_line (RFC822BUFFER *buf,char *type,long resent,
				char *text)
{
  return !text ||
    ((resent ? rfc822_output_string (buf,resentprefix) : LONGT) &&
     rfc822_output_string (buf,type) && rfc822_output_string (buf,": ") &&
     rfc822_output_string (buf,text) && rfc822_output_string (buf,"\015\012"));
}


/* Output RFC 2822 header address line
 * Accepts: buffer
 *	    pointer to header type
 *	    non-NIL if resending
 *	    address(s) to interpret
 *	    non-standard specials to be used for phrases if non-NIL
 * Returns: T if success, NIL if failure
 */

long rfc822_output_address_line (RFC822BUFFER *buf,char *type,long resent,
				 ADDRESS *adr,const char *specials)
{
  long pretty = strlen (type);
  return !adr ||
    ((resent ? rfc822_output_string (buf,resentprefix) : LONGT) &&
     rfc822_output_data (buf,type,pretty) && rfc822_output_string (buf,": ") &&
     rfc822_output_address_list (buf,adr,
				 resent ? pretty + sizeof (RESENTPREFIX) - 1 :
				 pretty,specials) &&
     rfc822_output_string (buf,"\015\012"));
}

/* Output RFC 2822 address list
 * Accepts: buffer
 *	    pointer to address list
 *	    non-zero if pretty-printing
 *	    non-standard specials to be used for phrases if non-NIL