rfc822.c

广泛使用的邮件服务器！同时

      case '\015':		/* handle CRLF form */
	if (CHR (bs) == '\012'){/* following LF? */
	  c = SNX (bs); i--;	/* yes, slurp it */
	}
      case '\012':		/* at start of a line, start with -- ? */
	if (!(i && i-- && ((c = SNX (bs)) == '-') && i-- &&
	      ((c = SNX (bs)) == '-'))) break;
				/* see if cookie matches */
	if (k = j - 2) for (s = s1; i-- && *s++ == (c = SNX (bs)) && --k;);
	if (k) break;		/* strings didn't match if non-zero */
				/* terminating delimiter? */
	if ((c = ((i && i--) ? (SNX (bs)) : '\012')) == '-') {
	  if ((i && i--) && ((c = SNX (bs)) == '-') &&
	      ((i && i--) ? (((c = SNX (bs)) == '\015') || (c=='\012')):T)) {
				/* if have a final part calculate its size */
	    if (part) part->body.mime.text.size =
	      (m > part->body.mime.offset) ? (m - part->body.mime.offset) :0;
	    part = NIL; i = 1;	/* terminate scan */
	  }
	  break;
	}
				/* swallow trailing whitespace */
	while ((c == ' ') || (c == '\t'))
	  c = ((i && i--) ? (SNX (bs)) : '\012');
	switch (c) {		/* need newline after all of it */
	case '\015':		/* handle CRLF form */
	  if (i && CHR (bs) == '\012') {
	    c = SNX (bs); i--;/* yes, slurp it */
	  }
	case '\012':		/* new line */
	  if (part) {		/* calculate size of previous */
	    part->body.mime.text.size =
	      (m > part->body.mime.offset) ? (m-part->body.mime.offset) : 0;
	    /* instantiate next */
	    part = part->next = mail_newbody_part ();
	  }			/* otherwise start new list */
	  else part = body->nested.part = mail_newbody_part ();
				/* digest has a different default */
	  if (f) part->body.type = TYPEMESSAGE;
				/* note offset from main body */
	  part->body.mime.offset = GETPOS (bs);
	  break;
	default:		/* whatever it was it wasn't valid */
	  break;
	}
	break;
      default:			/* not at a line */
	c = SNX (bs); i--;	/* get next character */
	break;
      }
    }

				/* calculate size of any final part */
    if (part) part->body.mime.text.size = i +
      ((GETPOS(bs) > part->body.mime.offset) ?
       (GETPOS(bs) - part->body.mime.offset) : 0);
				/* make a scratch buffer */
    s1 = (char *) fs_get ((size_t) (k = MAILTMPLEN));
				/* in case empty multipart */
    if (!body->nested.part) body->nested.part = mail_newbody_part ();
				/* parse non-empty body parts */
    for (part = body->nested.part; part; part = part->next) {
				/* part non-empty (header and/or content)? */
      if (i = part->body.mime.text.size) {
				/* move to that part of the body */
	SETPOS (bs,part->body.mime.offset);
				/* until end of header */
	while (i && ((c = CHR (bs)) != '\015') && (c != '\012')) {
				/* collect text until logical end of line */
	  for (j = 0,c = ' '; c; ) {
				/* make sure buffer big enough */
	    if (j > (k - 10)) fs_resize ((void **) &s1,k += MAILTMPLEN);
	    switch (c1 = SNX (bs)) {
	    case '\015':	/* return */
	      if (i && (CHR (bs) == '\012')) {
		c1 = SNX (bs);	/* eat any LF following */
		i--;
	      }
	    case '\012':	/* newline, possible end of logical line */
				/* tie off unless continuation */
	      if (!i || ((CHR (bs) != ' ') && (CHR (bs) != '\t')))
		s1[j] = c = '\0';
	      break;
	    case '\t':		/* tab */
	    case ' ':		/* insert whitespace if not already there */
	      if (c != ' ') s1[j++] = c = ' ';
	      break;
	    default:		/* all other characters */
	      s1[j++] = c = c1;	/* insert the character into the line */
	      break;
	    }
				/* end of data ties off the header */
	    if (!i || !--i) s1[j++] = c = '\0';
	  }

				/* find header item type */
	  if (((s1[0] == 'C') || (s1[0] == 'c')) &&
	      ((s1[1] == 'O') || (s1[1] == 'o')) &&
	      ((s1[2] == 'N') || (s1[2] == 'n')) &&
	      ((s1[3] == 'T') || (s1[3] == 't')) &&
	      ((s1[4] == 'E') || (s1[4] == 'e')) &&
	      ((s1[5] == 'N') || (s1[5] == 'n')) &&
	      ((s1[6] == 'T') || (s1[6] == 't')) &&
	      (s1[7] == '-') && (s = strchr (s1+8,':'))) {
				/* tie off and flush whitespace */
	    for (*s++ = '\0'; *s == ' '; s++);
				/* parse the header */
	    rfc822_parse_content_header (&part->body,ucase (s1+8),s);
	  }
	}
				/* skip header trailing (CR)LF */
	if (i && (CHR (bs) =='\015')) {i--; c1 = SNX (bs);}
	if (i && (CHR (bs) =='\012')) {i--; c1 = SNX (bs);}
	j = bs->size;		/* save upper level size */
				/* set offset for next level, fake size to i */
	bs->size = GETPOS (bs) + i;
	part->body.mime.text.size -= i;
				/* now parse it */
	rfc822_parse_content (&part->body,bs,h,depth+1,flags);
	bs->size = j;		/* restore current level size */
      }
      else {			/* zero-length part, use default subtype */
	part->body.subtype = cpystr (rfc822_default_subtype (part->body.type));
				/* see if anything else special to do */
	switch (part->body.type) {
	case TYPETEXT:		/* text content */
				/* default parameters */
	  if (!part->body.parameter) {
	    part->body.parameter = mail_newbody_parameter ();
	    part->body.parameter->attribute = cpystr ("CHARSET");
				/* only assume US-ASCII if 7BIT */
	    part->body.parameter->value =
	      cpystr ((part->body.encoding == ENC7BIT) ?
		      "US-ASCII" : "X-UNKNOWN");
	  }
	  break;
	case TYPEMESSAGE:	/* encapsulated message in digest */
	  part->body.nested.msg = mail_newmsg ();
	  break;
	default:
	  break;
	}
      }
    }
    fs_give ((void **) &s1);	/* finished with scratch buffer */
    break;
  default:			/* nothing special to do in any other case */
    break;
  }
}

/* Parse RFC 2822 body content header
 * Accepts: body to write to
 *	    possible content name
 *	    remainder of header
 */

void rfc822_parse_content_header (BODY *body,char *name,char *s)
{
  char c,*t,tmp[MAILTMPLEN];
  long i;
  STRINGLIST *stl;
  rfc822_skipws (&s);		/* skip leading comments */
				/* flush whitespace */
  if (t = strchr (name,' ')) *t = '\0';
  switch (*name) {		/* see what kind of content */
  case 'I':			/* possible Content-ID */
    if (!(strcmp (name+1,"D") || body->id)) body->id = cpystr (s);
    break;
  case 'D':			/* possible Content-Description */
    if (!(strcmp (name+1,"ESCRIPTION") || body->description))
      body->description = cpystr (s);
    if (!(strcmp (name+1,"ISPOSITION") || body->disposition.type)) {
				/* get type word */
      if (!(name = rfc822_parse_word (s,tspecials))) break;
      c = *name;		/* remember delimiter */
      *name = '\0';		/* tie off type */
      body->disposition.type = ucase (cpystr (s));
      *name = c;		/* restore delimiter */
      rfc822_skipws (&name);	/* skip whitespace */
      rfc822_parse_parameter (&body->disposition.parameter,name);
    }
    break;
  case 'L':			/* possible Content-Language */
    if (!(strcmp (name+1,"ANGUAGE") || body->language)) {
      stl = NIL;		/* process languages */
      while (s && (name = rfc822_parse_word (s,tspecials))) {
	c = *name;		/* save delimiter */
	*name = '\0';		/* tie off subtype */
	if (stl) stl = stl->next = mail_newstringlist ();
	else stl = body->language = mail_newstringlist ();
	stl->text.data = (unsigned char *) ucase (cpystr (s));
	stl->text.size = strlen ((char *) stl->text.data);
	*name = c;		/* restore delimiter */
	rfc822_skipws (&name);	/* skip whitespace */
	if (*name == ',') {	/* any more languages? */
	  s = ++name;		/* advance to it them */
	  rfc822_skipws (&s);
	}
	else s = NIL;		/* bogus or end of list */
      }
    }
    else if (!(strcmp (name+1,"OCATION") || body->location))
      body->location = cpystr (s);
    break;
  case 'M':			/* possible Content-MD5 */
    if (!(strcmp (name+1,"D5") || body->md5)) body->md5 = cpystr (s);
    break;

  case 'T':			/* possible Content-Type/Transfer-Encoding */
    if (!(strcmp (name+1,"YPE") || body->subtype || body->parameter)) {
				/* get type word */
      if (!(name = rfc822_parse_word (s,tspecials))) break;
      c = *name;		/* remember delimiter */
      *name = '\0';		/* tie off type */
				/* search for body type */
      for (i = 0,s = rfc822_cpy (s);
	   (i <= TYPEMAX) && body_types[i] &&
	     compare_cstring (s,body_types[i]); i++);
      if (i > TYPEMAX) {	/* fell off end of loop? */
	body->type = TYPEOTHER;	/* coerce to X-UNKNOWN */
	sprintf (tmp,"MIME type table overflow: %.100s",s);
	MM_LOG (tmp,PARSE);
      }
      else {			/* record body type index */
	body->type = (unsigned short) i;
				/* and name if new type */
	if (body_types[body->type]) fs_give ((void **) &s);
	else {			/* major MIME body type unknown to us */
	  body_types[body->type] = ucase (s);
	  sprintf (tmp,"Unknown MIME type: %.100s",s);
	  MM_LOG (tmp,PARSE);
	}
      }
      *name = c;		/* restore delimiter */
      rfc822_skipws (&name);	/* skip whitespace */
      if ((*name == '/') &&	/* subtype? */
	  (name = rfc822_parse_word ((s = ++name),tspecials))) {
	c = *name;		/* save delimiter */
	*name = '\0';		/* tie off subtype */
	rfc822_skipws (&s);	/* copy subtype */
	if (s) body->subtype = ucase (rfc822_cpy (s));
	*name = c;		/* restore delimiter */
	rfc822_skipws (&name);	/* skip whitespace */
      }
      else if (!name) {		/* no subtype, was a subtype delimiter? */
	name = s;		/* barf, restore pointer */
	rfc822_skipws (&name);	/* skip leading whitespace */
      }
      rfc822_parse_parameter (&body->parameter,name);
    }

    else if (!strcmp (name+1,"RANSFER-ENCODING")) {
      if (!(name = rfc822_parse_word (s,tspecials))) break;
      c = *name;		/* remember delimiter */
      *name = '\0';		/* tie off encoding */
				/* search for body encoding */      
      for (i = 0,s = rfc822_cpy (s);
	   (i <= ENCMAX) && body_encodings[i] &&
	     compare_cstring (s,body_encodings[i]); i++);
      if (i > ENCMAX) {		/* fell off end of loop? */
	body->encoding = ENCOTHER;
	sprintf (tmp,"MIME encoding table overflow: %.100s",s);
	MM_LOG (tmp,PARSE);
      }
      else {			/* record body encoding index */
	body->encoding = (unsigned short) i;
				/* and name if new encoding */
	if (body_encodings[body->encoding]) fs_give ((void **) &s);
	else {
	  body_encodings[body->encoding] = ucase (s);
	  sprintf (tmp,"Unknown MIME transfer encoding: %.100s",s);
	  MM_LOG (tmp,PARSE);
	}
      }
      *name = c;		/* restore delimiter */
      /* ??check for cruft here?? */
    }
    break;
  default:			/* otherwise unknown */
    break;
  }
}

/* Parse RFC 2822 body parameter list
 * Accepts: parameter list to write to
 *	    text of list
 */

void rfc822_parse_parameter (PARAMETER **par,char *text)
{
  char c,*s,tmp[MAILTMPLEN];
  PARAMETER *param = NIL;
				/* parameter list? */
  while (text && (*text == ';') &&
	 (text = rfc822_parse_word ((s = ++text),tspecials))) {
    c = *text;			/* remember delimiter */
    *text = '\0';		/* tie off attribute name */
    rfc822_skipws (&s);		/* skip leading attribute whitespace */
    if (!*s) *text = c;		/* must have an attribute name */
    else {			/* instantiate a new parameter */
      if (*par) param = param->next = mail_newbody_parameter ();
      else param = *par = mail_newbody_parameter ();
      param->attribute = ucase (cpystr (s));
      *text = c;		/* restore delimiter */
      rfc822_skipws (&text);	/* skip whitespace before equal sign */
      if ((*text == '=') &&	/* make sure have value */
	  (text = rfc822_parse_word ((s = ++text),tspecials))) {
	c = *text;		/* remember delimiter */
	*text = '\0';		/* tie off value */
	rfc822_skipws (&s);	/* skip leading value whitespace */
	if (*s) param->value = rfc822_cpy (s);
	*text = c;		/* restore delimiter */
	rfc822_skipws (&text);
      }
      if (!param->value) {	/* value not found? */
	param->value = cpystr ("MISSING_PARAMETER_VALUE");
	sprintf (tmp,"Missing parameter value: %.80s",param->attribute);
	MM_LOG (tmp,PARSE);
      }
    }
  }
				/* string not present */
  if (!text) MM_LOG ("Missing parameter",PARSE);
  else if (*text) {		/* must be end of poop */
    sprintf (tmp,"Unexpected characters at end of parameters: %.80s",text);
    MM_LOG (tmp,PARSE);
  }
}

/* Parse RFC 2822 address list
 * Accepts: address list to write to
 *	    input string
 *	    default host name
 */

void rfc822_parse_adrlist (ADDRESS **lst,char *string,char *host)
{
  int c;
  char *s,tmp[MAILTMPLEN];
  ADDRESS *last = *lst;
  ADDRESS *adr;
  if (!string) return;		/* no string */
  rfc822_skipws (&string);	/* skip leading WS */
  if (!*string) return;		/* empty string */
				/* run to tail of list */
  if (last) while (last->next) last = last->next;
  while (string) {		/* loop until string exhausted */
    while (*string == ',') {	/* RFC 822 allowed null addresses!! */
      ++string;			/* skip the comma */
      rfc822_skipws (&string);	/* and any leading WS */
    }
    if (!*string) string = NIL;	/* punt if ran out of string */
				/* got an address? */
    else if (adr = rfc822_parse_address (lst,last,&string,host,0)) {
      last = adr;		/* new tail address */
      if (string) {		/* analyze what follows */
	rfc822_skipws (&string);
	switch (c = *(unsigned char *) string) {
	case ',':		/* comma? */
	  ++string;		/* then another address follows */
	  break;
	default:
	  s = isalnum (c) ? "Must use comma to separate addresses: %.80s" :
	    "Unexpected characters at end of address: %.80s";
	  sprintf (tmp,s,string);
	  MM_LOG (tmp,PARSE);
	  last = last->next = mail_newaddr ();
	  last->mailbox = cpystr ("UNEXPECTED_DATA_AFTER_ADDRESS");
	  last->host = cpystr (errhst);
				/* falls through */
	case '\0':		/* null-specified address? */
	  string = NIL;		/* punt remainder of parse */
	  break;
	}
      }
    }
    else if (string) {		/* bad mailbox */
      rfc822_skipws (&string);	/* skip WS */
      if (!*string) strcpy (tmp,"Missing address after comma");
      else sprintf (tmp,"Invalid mailbox list: %.80s",string);
      MM_LOG (tmp,PARSE);