rfc822.c

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 * Returns: T if success, NIL if failure
 */

long rfc822_output_address_list (RFC822BUFFER *buf,ADDRESS *adr,long pretty,
				 const char *specials)
{
  long n;
				/* default to rspecials */
  if (!specials) specials = rspecials;
  for (n = 0; adr; adr = adr->next) {
    char *base = buf->cur;
    if (adr->host) {		/* ordinary address? */
      if (!(pretty && n)) {	/* suppress if pretty and in group */
	if (			/* use phrase <route-addr> if phrase */
#if RFC822
	    adr->adl ||		/* or A-D-L */
#endif
	    (adr->personal && *adr->personal)) {
	  if (!((adr->personal ? rfc822_output_cat (buf,adr->personal,
						    rspecials) : LONGT) &&
		rfc822_output_string (buf," <") &&
		rfc822_output_address (buf,adr) &&
		rfc822_output_string (buf,">"))) return NIL;
	}
	else if (!rfc822_output_address (buf,adr)) return NIL;
	if (adr->next && adr->next->mailbox &&
	    !rfc822_output_string (buf,", ")) return NIL;
      }
    }
    else if (adr->mailbox) {	/* start of group? */
				/* yes, write group */
      if (!(rfc822_output_cat (buf,adr->mailbox,rspecials) &&
	    rfc822_output_string (buf,": "))) return NIL;
      ++n;			/* in a group now */
    }
    else if (n) {		/* must be end of group (but be paranoid) */
      if (!rfc822_output_char (buf,';') ||
	  ((!--n && adr->next && adr->next->mailbox) &&
	   !rfc822_output_string (buf,", "))) return NIL;
    }
    if (pretty && adr->next &&	/* pretty printing? */
	((pretty += ((buf->cur > base) ? buf->cur - base :
		     (buf->end - base) + (buf->cur - buf->beg))) >= 78)) {
      if (!(rfc822_output_string (buf,"\015\012") &&
	    rfc822_output_string (buf,RFC822CONT))) return NIL;
      base = buf->cur;	/* update base for pretty printing */
      pretty = sizeof (RFC822CONT) - 1;
    }
  }
  return LONGT;
}

/* Write RFC 2822 route-address to string
 * Accepts: buffer
 *	    pointer to single address
 * Returns: T if success, NIL if failure
 */

long rfc822_output_address (RFC822BUFFER *buf,ADDRESS *adr)
{
  return !adr || !adr->host ||
    (
#if RFC822			/* old code with A-D-L support */
     (!adr->adl || (rfc822_output_string (buf,adr->adl) &&
		    rfc822_output_char (buf,':'))) &&
#endif
     rfc822_output_cat (buf,adr->mailbox,NIL) &&
     ((*adr->host == '@') ||	/* unless null host (HIGHLY discouraged!) */
      (rfc822_output_char (buf,'@') &&
       rfc822_output_cat (buf,adr->host,NIL))));
}


/* Output RFC 2822 string with concatenation
 * Accepts: buffer
 *	    string to concatenate
 *	    list of special characters or NIL for dot-atom format
 * Returns: T if success, NIL if failure
 */

long rfc822_output_cat (RFC822BUFFER *buf,char *src,const char *specials)
{
  char *s;
  if (!*src ||			/* empty string or any specials present? */
      (specials ? (T && strpbrk (src,specials)) :
       (strpbrk (src,wspecials) || (*src == '.') || strstr (src,"..") ||
	(src[strlen (src) - 1] == '.')))) {
				/* yes, write as quoted string*/
    if (!rfc822_output_char (buf,'"')) return NIL;
				/* embedded quote characters? */
    for (; s = strpbrk (src,"\\\""); src = s + 1) {
				/* yes, insert quoting */
      if (!(rfc822_output_data (buf,src,s-src) &&
	    rfc822_output_char (buf,'\\') &&
	    rfc822_output_char (buf,*s))) return NIL;
    }
				/* return string and trailing quote*/
    return rfc822_output_string (buf,src) && rfc822_output_char (buf,'"');
  }
				/* easy case */
  return rfc822_output_string (buf,src);
}

/* Output MIME parameter list
 * Accepts: buffer
 *	    parameter list
 * Returns: T if success, NIL if failure
 */

long rfc822_output_parameter (RFC822BUFFER *buf,PARAMETER *param)
{
  while (param) {
    if (rfc822_output_string (buf,"; ") &&
	rfc822_output_string (buf,param->attribute) &&
	rfc822_output_char (buf,'=') &&
	rfc822_output_cat (buf,param->value,tspecials)) param = param->next;
    else return NIL;
  }
  return LONGT;
}


/* Output RFC 2822 stringlist
 * Accepts: buffer
 *	    stringlist
 * Returns: T if success, NIL if failure
 */

long rfc822_output_stringlist (RFC822BUFFER *buf,STRINGLIST *stl)
{
  while (stl)
    if (!rfc822_output_cat (buf,(char *) stl->text.data,tspecials) ||
	((stl = stl->next) && !rfc822_output_string (buf,", ")))
      return NIL;
  return LONGT;
}

/* Output body content header
 * Accepts: buffer
 *	    body to interpret
 * Returns: T if success, NIL if failure
 */

long rfc822_output_body_header (RFC822BUFFER *buf,BODY *body)
{
  return			/* type and subtype*/
    rfc822_output_string (buf,"Content-Type: ") &&
    rfc822_output_string (buf,body_types[body->type]) &&
    rfc822_output_char (buf,'/') &&
    rfc822_output_string (buf,body->subtype ? body->subtype :
			  rfc822_default_subtype (body->type)) &&
				/* parameters (w/ US-ASCII default */
    (body->parameter ? rfc822_output_parameter (buf,body->parameter) :
     ((body->type != TYPETEXT) ||
      (rfc822_output_string (buf,"; CHARSET=") &&
       rfc822_output_string (buf,(body->encoding == ENC7BIT) ?
			     "US-ASCII" : "X-UNKNOWN")))) &&
    (!body->encoding ||	    /* note: 7BIT never output as encoding! */
     (rfc822_output_string (buf,"\015\012Content-Transfer-Encoding: ") &&
      rfc822_output_string (buf,body_encodings[body->encoding]))) &&
    (!body->id ||		/* identification */
     (rfc822_output_string (buf,"\015\012Content-ID: ") &&
      rfc822_output_string (buf,body->id))) &&
    (!body->description ||	/* description */
     (rfc822_output_string (buf,"\015\012Content-Description: ") &&
      rfc822_output_string (buf,body->description))) &&
    (!body->md5 ||		/* MD5 checksum */
     (rfc822_output_string (buf,"\015\012Content-MD5: ") &&
      rfc822_output_string (buf,body->md5))) &&
    (!body->language ||		/* language */
     (rfc822_output_string (buf,"\015\012Content-Language: ") &&
      rfc822_output_stringlist (buf,body->language))) &&
    (!body->location ||		/* location */
     (rfc822_output_string (buf,"\015\012Content-Location: ") &&
      rfc822_output_string (buf,body->location))) &&
    (!body->disposition.type ||	/* disposition */
     (rfc822_output_string (buf,"\015\012Content-Disposition: ") &&
      rfc822_output_string (buf,body->disposition.type) &&
      rfc822_output_parameter (buf,body->disposition.parameter))) &&
    rfc822_output_string (buf,"\015\012");
}

/* Encode a body for 7BIT transmittal
 * Accepts: envelope
 *	    body
 */

void rfc822_encode_body_7bit (ENVELOPE *env,BODY *body)
{
  void *f;
  PART *part;
  PARAMETER **param;
  if (body) switch (body->type) {
  case TYPEMULTIPART:		/* multi-part */
    for (param = &body->parameter;
	 *param && strcmp ((*param)->attribute,"BOUNDARY");
	 param = &(*param)->next);
    if (!*param) {		/* cookie not set up yet? */
      char tmp[MAILTMPLEN];	/* make cookie not in BASE64 or QUOTEPRINT*/
      sprintf (tmp,"%lu-%lu-%lu=:%lu",(unsigned long) gethostid (),
	       (unsigned long) random (),(unsigned long) time (0),
	       (unsigned long) getpid ());
      (*param) = mail_newbody_parameter ();
      (*param)->attribute = cpystr ("BOUNDARY");
      (*param)->value = cpystr (tmp);
    }
    part = body->nested.part;	/* encode body parts */
    do rfc822_encode_body_7bit (env,&part->body);
    while (part = part->next);	/* until done */
    break;
  case TYPEMESSAGE:		/* encapsulated message */
    switch (body->encoding) {
    case ENC7BIT:
      break;
    case ENC8BIT:
      MM_LOG ("8-bit included message in 7-bit message body",PARSE);
      break;
    case ENCBINARY:
      MM_LOG ("Binary included message in 7-bit message body",PARSE);
      break;
    default:
      fatal ("Invalid rfc822_encode_body_7bit message encoding");
    }
    break;			/* can't change encoding */
  default:			/* all else has some encoding */
    switch (body->encoding) {
    case ENC8BIT:		/* encode 8BIT into QUOTED-PRINTABLE */
				/* remember old 8-bit contents */
      f = (void *) body->contents.text.data;
      body->contents.text.data =
	rfc822_8bit (body->contents.text.data,
		     body->contents.text.size,&body->contents.text.size);
      body->encoding = ENCQUOTEDPRINTABLE;
      fs_give (&f);		/* flush old binary contents */
      break;
    case ENCBINARY:		/* encode binary into BASE64 */
				/* remember old binary contents */
      f = (void *) body->contents.text.data;
      body->contents.text.data =
	rfc822_binary ((void *) body->contents.text.data,
		       body->contents.text.size,&body->contents.text.size);
      body->encoding = ENCBASE64;
      fs_give (&f);		/* flush old binary contents */
    default:			/* otherwise OK */
      break;
    }
    break;
  }
}

/* Encode a body for 8BIT transmittal
 * Accepts: envelope
 *	    body
 */

void rfc822_encode_body_8bit (ENVELOPE *env,BODY *body)
{
  void *f;
  PART *part;
  PARAMETER **param;
  if (body) switch (body->type) {
  case TYPEMULTIPART:		/* multi-part */
    for (param = &body->parameter;
	 *param && strcmp ((*param)->attribute,"BOUNDARY");
	 param = &(*param)->next);
    if (!*param) {		/* cookie not set up yet? */
      char tmp[MAILTMPLEN];	/* make cookie not in BASE64 or QUOTEPRINT*/
      sprintf (tmp,"%lu-%lu-%lu=:%lu",(unsigned long) gethostid (),
	       (unsigned long) random (),(unsigned long) time (0),
	       (unsigned long) getpid ());
      (*param) = mail_newbody_parameter ();
      (*param)->attribute = cpystr ("BOUNDARY");
      (*param)->value = cpystr (tmp);
    }
    part = body->nested.part;	/* encode body parts */
    do rfc822_encode_body_8bit (env,&part->body);
    while (part = part->next);	/* until done */
    break;
  case TYPEMESSAGE:		/* encapsulated message */
    switch (body->encoding) {
    case ENC7BIT:
    case ENC8BIT:
      break;
    case ENCBINARY:
      MM_LOG ("Binary included message in 8-bit message body",PARSE);
      break;
    default:
      fatal ("Invalid rfc822_encode_body_7bit message encoding");
    }
    break;			/* can't change encoding */
  default:			/* other type, encode binary into BASE64 */
    if (body->encoding == ENCBINARY) {
				/* remember old binary contents */
      f = (void *) body->contents.text.data;
      body->contents.text.data =
	rfc822_binary ((void *) body->contents.text.data,
		       body->contents.text.size,&body->contents.text.size);
      body->encoding = ENCBASE64;
      fs_give (&f);		/* flush old binary contents */
    }
    break;
  }
}

/* Output RFC 822 text
 * Accepts: buffer
 *	    body
 * Returns: T if successful, NIL if failure
 */

long rfc822_output_text (RFC822BUFFER *buf,BODY *body)
{
				/* MULTIPART gets special handling */
  if (body->type == TYPEMULTIPART) {
    char *cookie,tmp[MAILTMPLEN];
    PARAMETER *param;
    PART *part;
				/* find cookie */
    for (param = body->parameter; param && strcmp (param->attribute,"BOUNDARY");
	 param = param->next);
    if (param) cookie = param->value;
    else {		  /* make cookie not in BASE64 or QUOTEPRINT*/
      sprintf (cookie = tmp,"%lu-%lu-%lu=:%lu",(unsigned long) gethostid (),
	       (unsigned long) random (),(unsigned long) time (0),
	       (unsigned long) getpid ());
      (param = mail_newbody_parameter ())->attribute = cpystr ("BOUNDARY");
      param->value = cpystr (tmp);
      param->next = body->parameter;
      body->parameter = param;
    }
				/* output each part */
    for (part = body->nested.part; part; part = part->next)
      if (!(rfc822_output_string (buf,"--") &&
	    rfc822_output_string (buf,cookie) &&
	    rfc822_output_string (buf,"\015\012") &&
	    rfc822_output_body_header (buf,&part->body) &&
	    rfc822_output_string (buf,"\015\012") &&
	    rfc822_output_text (buf,&part->body))) return NIL;
				/* output trailing cookie */
    return rfc822_output_string (buf,"--") &&
      rfc822_output_string (buf,cookie) &&
      rfc822_output_string (buf,"--\015\012");
  }
				/* output segment and trailing CRLF */
  return (!body->contents.text.data ||
	  rfc822_output_string (buf,(char *) body->contents.text.data)) &&
    rfc822_output_string (buf,"\015\012");
}

/* Body contents encoding/decoding routines */


/* Convert BASE64 contents to binary
 * Accepts: source
 *	    length of source
 *	    pointer to return destination length
 * Returns: destination as binary or NIL if error
 */

#define WSP 0176		/* NUL, TAB, LF, FF, CR, SPC */
#define JNK 0177
#define PAD 0100

void *rfc822_base64 (unsigned char *src,unsigned long srcl,unsigned long *len)
{
  char c,*s,tmp[MAILTMPLEN];
  void *ret = fs_get ((size_t) ((*len = 4 + ((srcl * 3) / 4))) + 1);
  char *d = (char *) ret;
  int e;
  static char decode[256] = {
   WSP,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,WSP,WSP,JNK,WSP,WSP,JNK,JNK,
   JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,
   WSP,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,076,JNK,JNK,JNK,077,
   064,065,066,067,070,071,072,073,074,075,JNK,JNK,JNK,PAD,JNK,JNK,
   JNK,000,001,002,003,004,005,006,007,010,011,012,013,014,015,016,
   017,020,021,022,023,024,025,026,027,030,031,JNK,JNK,JNK,JNK,JNK,
   JNK,032,033,034,035,036,037,040,041,042,043,044,045,046,047,050,
   051,052,053,054,055,056,057,060,061,062,063,JNK,JNK,JNK,JNK,JNK,
   JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,JNK,
   JNK,JNK,J