/* Distributed Checksum Clearinghouse
 *
 * SMTP reply strings
 *
 * Copyright (c) 2006 by Rhyolite Software, LLC
 *
 * This agreement is not applicable to any entity which sells anti-spam
 * solutions to others or provides an anti-spam solution as part of a
 * security solution sold to other entities, or to a private network
 * which employs the DCC or uses data provided by operation of the DCC
 * but does not provide corresponding data to other users.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * Parties not eligible to receive a license under this agreement can
 * obtain a commercial license to use DCC and permission to use
 * U.S. Patent 6,330,590 by contacting Commtouch at http://www.commtouch.com/
 * or by email to nospam@commtouch.com.
 *
 * A commercial license would be for Distributed Checksum and Reputation
 * Clearinghouse software.  That software includes additional features.  This
 * free license for Distributed ChecksumClearinghouse Software does not in any
 * way grant permision to use Distributed Checksum and Reputation Clearinghouse
 * software
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND RHYOLITE SOFTWARE, LLC DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL RHYOLITE SOFTWARE, LLC
 * BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
 * ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 *
 * Rhyolite Software DCC 1.3.50-1.21 $Revision$
 */


#include "cmn_defs.h"

REPLY reject_reply;
REPLY reputation_reply;
REPLY grey_reply;


/* default SMTP messages */
typedef struct {
    REPLY *reply;
    const char *rcode;			/* default value such as "550" */
    const char *xcode;			/* default value such as "5.7.1" */
    const char *def_pat;		/* default -r pattern */
    const char *log_result;		/* "accept ..." etc. for log */
} REPLY_DEF;

#define	DEF_REJ_MSG "mail %s from %s rejected by DCC"
static REPLY_DEF rej_def = {&reject_reply, DCC_RCODE, DCC_XCODE,
	DEF_REJ_MSG,
	"reject"};

static REPLY_DEF rep_def = {&reputation_reply, DCC_RCODE, DCC_XCODE,
	"%s bad reputation; see http://commercial-dcc.rhyolite.com/cgi-bin/reps.cgi?tgt=%s",
	"reject by DCC reputation"};

static REPLY_DEF grey_def = {&grey_reply, "452", "4.2.1",
	"mail %s from %s temporary greylist embargoed",
	"temporary greylist embargo"};

static REPLY_DEF dnsbl_def = {0, DCC_RCODE, DCC_XCODE,
	DEF_REJ_MSG,
	"reject"};


REPLY dcc_fail_reply = {"remporary reject",
	"451", "4.4.0", DCC_XHDR_RESULT_DCC_FAIL};


/* Parse a string into RFC 821 and RFC 2034 codes and a pattern to make a
 * message, or generate the codes for a string that has a message
 * without codes.
 * The should be something like "5.7.1 550 spammer go home"
 * or "spammer go home".
 * The pattern can have as many as two "%s" references to the sendmail
 * queue-ID and SMTP client IP address.
 */
void
parse_reply(REPLY *reply,		/* to here */
	    u_char pat_ok,		/* 1=allow %s in pattern */
	    const char *xcode,		/* default value such as "5.7.1" */
	    const char *rcode,		/* default value such as "550" */
	    const char *arg,		/* using this pattern */
	    const char *log_result)	/* "reject" etc. for log */
{
	const char *p;
	char sb[5+1+3+1];
	int p_cnt, i;

	/* Does the message have a valid xcode and rcode?
	 * First check for sendmail.cf ERROR:### and ERROR:D.S.N:### */
	if (!pat_ok && !CSTRCMP(arg, "ERROR:")) {
		p = dcc_parse_word(0, sb, sizeof(sb), arg+STRZ("ERROR:"),
				   0, 0, 0);
		if (p) {
			i = strlen(sb);
			if (i == 5+1+3 && sb[5] == ':') {
				memcpy(reply->xcode, &sb[0], 5);
				memcpy(reply->rcode, &sb[6], 3);
			} else if (i == 3) {
				BUFCPY(reply->xcode, xcode);
				memcpy(reply->rcode, &sb[0], 3);
			} else {
				p = 0;
			}
		}
	} else {
		p = dcc_parse_word(0, reply->xcode, sizeof(reply->xcode), arg,
				   0, 0, 0);
		p = dcc_parse_word(0, reply->rcode, sizeof(reply->rcode), p,
				   0, 0, 0);
	}
	if (!p
	    || reply->rcode[0] < '4' || reply->rcode[0] > '5'
	    || reply->rcode[1] < '0' || reply->rcode[1] > '9'
	    || reply->rcode[2] < '0' || reply->rcode[2] > '9'
	    || reply->rcode[0] != reply->xcode[0]
	    || reply->xcode[1] != '.'
	    || reply->xcode[2] < '0' || reply->xcode[2] > '9'
	    || reply->xcode[3] != '.'
	    || reply->xcode[4] < '0' || reply->xcode[4] > '9') {
		BUFCPY(reply->xcode, xcode);
		BUFCPY(reply->rcode, rcode);
		p = arg;
	}

	p += strspn(p, DCC_WHITESPACE);
	if (!pat_ok || !strchr(p, '%')) {
		BUFCPY(reply->buf, p);
	} else {
		u_char c;
		char *new_pat;

		p_cnt = 0;
		new_pat = reply->buf;
		do {
			c = *p++;
			if (c == '\0')
				break;
			if (c == '%') {
				if (*p != 's' || ++p_cnt > 2)
					*new_pat++ = '%';
			} else if (c < ' ' || c > '~') {
				/* sendmail does not like control characters in
				 * SMTP status messages */
				c = '.';
			}
			*new_pat++ = c;
		} while (new_pat < LAST(reply->buf)-2);
		*new_pat = '\0';
	}

	reply->log_result = log_result;
}



static inline void
finish_reply(const REPLY_DEF *def, const char *pat)
{
	parse_reply(def->reply, 1, def->xcode, def->rcode, pat,
		    def->log_result);
}



void
finish_replies(void)
{
	/* make SMTP status strings for cases not set with -rPATTERN */
	if (reject_reply.rcode[0] == '\0')
		finish_reply(&rej_def, rej_def.def_pat);
	if (reputation_reply.rcode[0] == '\0')
		finish_reply(&rep_def, rep_def.def_pat);
	if (grey_reply.rcode[0] == '\0')
		finish_reply(&grey_def, grey_def.def_pat);
}



/* parse another "-r pattern" argument */
void
parse_reply_arg(const char *arg)
{
	/* a blank string implies the default */
	arg += strspn(arg, DCC_WHITESPACE);

	/* each -r finishes the next SMTP rejection message */

	if (reject_reply.rcode[0] == '\0') {
		if (*arg == '\0')
			finish_reply(&rej_def, rej_def.def_pat);
		else
			finish_reply(&rej_def, arg);
		return;
	}

	if (grey_reply.rcode[0] == '\0') {
		if (*arg == '\0') {
			finish_reply(&grey_def, grey_def.def_pat);
			return;
		}
		finish_reply(&grey_def, arg);
		if (grey_reply.rcode[0] != '4'
		    || grey_reply.xcode[0] != '4') {
			dcc_error_msg("invalid greylist message: %s", arg);
			finish_reply(&grey_def, grey_def.def_pat);
		}
		return;
	}

	if (reputation_reply.rcode[0] == '\0') {
		if (*arg == '\0')
			finish_reply(&rep_def, rep_def.def_pat);
		else
			finish_reply(&rep_def, arg);
		return;
	}

	dcc_error_msg("more than 3 -r settings");
}



/* set up the DNSBL SMTP error message for all threads based on a -B arg
 *	allow % patterns and so forth */
const REPLY *
dnsbl_parse_reply(const char *pat)
{
	REPLY *reply;

	reply = malloc(sizeof(REPLY));
	memset(reply, 0, sizeof(*reply));
	parse_reply(reply, 1, dnsbl_def.xcode, dnsbl_def.rcode, pat,
		    dnsbl_def.log_result);
	return reply;
}



void
make_reply(REPLY *reply, const REPLY *template, const CMN_WORK *cwp)
{
	memcpy(reply->rcode, template->rcode, sizeof(reply->rcode));
	memcpy(reply->xcode, template->xcode, sizeof(reply->xcode));
	snprintf(reply->buf, sizeof(reply->buf),
		 template->buf, cwp->id, dcc_trim_ffff(cwp->clnt_str));

	reply->log_result = template->log_result;
}