/*
 * convert from text form of subnet specification to binary
 *
 * Copyright (C) 2000  Henry Spencer.
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Library General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.  See <http://www.fsf.org/copyleft/lgpl.txt>.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
 * License for more details.
 */
#include "internal.h"
#include "libreswan.h"

#ifndef DEFAULTSUBNET
#define DEFAULTSUBNET "%default"
#endif

/*
 * ttosubnet - convert text "addr/mask" to address and mask
 * Mask can be integer bit count.
 */
err_t ttosubnet(src, srclen, af, dst)
const char *src;
size_t srclen;	/* 0 means "apply strlen" */
int af;	/* AF_INET or AF_INET6 */
ip_subnet *dst;
{
	const char *slash;
	const char *colon;
	const char *mask;
	size_t mlen;
	const char *oops;
	unsigned long bc;
	static const char def[] = DEFAULTSUBNET;
#define DEFLEN (sizeof(def) - 1)	/* -1 for NUL */
	static const char defis4[] = "0/0";
#define DEFIS4LEN (sizeof(defis4) - 1)
	static const char defis6[] = "::/0";
#define DEFIS6LEN (sizeof(defis6) - 1)
	ip_address addrtmp;
	ip_address masktmp;
	int nbits;
	int i;

	if (srclen == 0) {
		srclen = strlen(src);
		if (srclen == 0)
			return "empty string";
	}

	/*
	 * you cannot use af==AF_UNSPEC and src=0/0,
	 * makes no sense as will it be AF_INET
	 */
	if (srclen == DEFLEN && strncmp(src, def, srclen) == 0) {
		switch (af) {
		case AF_INET:
			src = defis4;
			srclen = DEFIS4LEN;
			break;
		case AF_INET6:
			src = defis6;
			srclen = DEFIS6LEN;
			break;
		default:
			return "unknown address family with " DEFAULTSUBNET " subnet not allowed.";
		}
	}

	slash = memchr(src, '/', srclen);
	if (slash == NULL)
		return "no / in subnet specification";

	mask = slash + 1;
	mlen = srclen - (mask - src);
	oops = ttoaddr(src, slash - src, af, &addrtmp);
	if (oops != NULL)
		return oops;

	if (af == AF_UNSPEC)
		af = addrtypeof(&addrtmp);

	switch (af) {
	case AF_INET:
		nbits = 32;
		break;
	case AF_INET6:
		nbits = 128;
		break;
	default:
		return "unknown address family in ttosubnet";
	}

	/* extract port, as last : */
	colon = memchr(mask, ':', mlen);
	if (colon == 0) {
		setportof(0, &addrtmp);
	} else {
		unsigned long port;

		oops =  ttoulb(colon + 1, mlen - (colon - mask + 1), 0, 0xFFFF, &port);
		if (oops != NULL)
			return oops;

		setportof(htons(port), &addrtmp);
		mlen = colon - mask;
	}

	/* extract mask */
	oops = ttoulb(mask, mlen, 10, nbits, &bc);
	if (oops == NULL) {
		/* ttoul succeeded, it's a bit-count mask */
		i = bc;
	} else if (af == AF_INET) {
		oops = ttoaddr(mask, mlen, af, &masktmp);
		if (oops != NULL)
			return oops;

		i = masktocount(&masktmp);
		if (i < 0)
			return "non-contiguous or otherwise erroneous mask";
	} else {
		return "masks are not permitted for IPv6 addresses";
	}
	return initsubnet(&addrtmp, i, '0', dst);
}

#ifdef TTOSUBNET_MAIN

#include <stdio.h>

void regress(void);

int main(int argc, char *argv[])
{
	ip_subnet s;
	char buf[100];
	char buf2[100];
	const char *oops;
	size_t n;
	int af;
	char *p;

	if (argc < 2) {
		fprintf(stderr, "Usage: %s [-6] addr/mask\n", argv[0]);
		fprintf(stderr, "   or: %s -r\n", argv[0]);
		exit(2);
	}

	if (streq(argv[1], "-r")) {
		regress();
		fprintf(stderr, "regress() returned?!?\n");
		exit(1);
	}

	af = AF_INET;
	p = argv[1];
	if (streq(argv[1], "-6")) {
		af = AF_INET6;
		p = argv[2];
	} else if (strchr(argv[1], ':') != NULL) {
		af = AF_INET6;
	}
	oops = ttosubnet(p, 0, af, &s);
	if (oops != NULL) {
		fprintf(stderr, "%s: conversion failed: %s\n", argv[0], oops);
		exit(1);
	}
	n = subnettot(&s, 0, buf, sizeof(buf));
	if (n > sizeof(buf)) {
		fprintf(stderr, "%s: reverse conversion of ", argv[0]);
		(void) addrtot(&s.addr, 0, buf2, sizeof(buf2));
		fprintf(stderr, "%s/", buf2);
		fprintf(stderr, "%d", s.maskbits);
		fprintf(stderr, " failed: need %ld bytes, have only %ld\n",
			(long)n, (long)sizeof(buf));
		exit(1);
	}
	printf("%s\n", buf);

	exit(0);
}

struct rtab {
	int family;
	char *input;
	char *output;	/* NULL means error expected */
} rtab[] = {
	{ 4, "1.2.3.0/255.255.255.0", "1.2.3.0/24" },
	{ 4, "1.2.3.0/24", "1.2.3.0/24" },
	{ 4, "1.2.3.0/24:10", "1.2.3.0/24:10" },
	{ 4, "1.2.3.0/24:-1", NULL },
	{ 4, "1.2.3.0/24:none", NULL },
	{ 4, "1.2.3.0/24:", NULL },
	{ 4, "1.2.3.0/24:0x10", "1.2.3.0/24:16" },
	{ 4, "1.2.3.0/24:0X10", "1.2.3.0/24:16" },
	{ 4, "1.2.3.0/24:010", "1.2.3.0/24:8" },
	{ 4, "1.2.3.1/255.255.255.240", "1.2.3.0/28" },
	{ 4, "1.2.3.1/32", "1.2.3.1/32" },
	{ 4, "1.2.3.1/0", "0.0.0.0/0" },
/*	{4, "1.2.3.1/255.255.127.0",	"1.2.3.0/255.255.127.0"}, */
	{ 4, "1.2.3.1/255.255.127.0", NULL },
	{ 4, "128.009.000.032/32", "128.9.0.32/32" },
	{ 4, "128.0x9.0.32/32", NULL },
	{ 4, "0x80090020/32", "128.9.0.32/32" },
	{ 4, "0x800x0020/32", NULL },
	{ 4, "128.9.0.32/0xffFF0000", "128.9.0.0/16" },
	{ 4, "128.9.0.32/0xff0000FF", NULL },
	{ 4, "128.9.0.32/0x0000ffFF", NULL },
	{ 4, "128.9.0.32/0x00ffFF0000", NULL },
	{ 4, "128.9.0.32/0xffFF", NULL },
	{ 4, "128.9.0.32.27/32", NULL },
	{ 4, "128.9.0k32/32", NULL },
	{ 4, "328.9.0.32/32", NULL },
	{ 4, "128.9..32/32", NULL },
	{ 4, "10/8", "10.0.0.0/8" },
	{ 4, "10.0/8", "10.0.0.0/8" },
	{ 4, "10.0.0/8", "10.0.0.0/8" },
	{ 4, "10.0.1/24", "10.0.1.0/24" },
	{ 4, "_", NULL },
	{ 4, "_/_", NULL },
	{ 4, "1.2.3.1", NULL },
	{ 4, "1.2.3.1/_", NULL },
	{ 4, "1.2.3.1/24._", NULL },
	{ 4, "1.2.3.1/99", NULL },
	{ 4, "localhost/32", NULL },
	{ 4, "%default", "0.0.0.0/0" },
	{ 6, "3049:1::8007:2040/0", "::/0" },
	{ 6, "3049:1::8007:2040/128", "3049:1::8007:2040/128" },
	{ 6, "3049:1::192.168.0.1/128", NULL },	/*"3049:1::c0a8:1/128",*/
	{ 6, "3049:1::8007::2040/128", NULL },
	{ 6, "3049:1::8007:2040/ffff:0", NULL },
	{ 6, "3049:1::8007:2040/64", "3049:1::/64" },
	{ 6, "3049:1::8007:2040/64:53", "3049:1::/64:53" },
	{ 6, "3049:1::8007:2040/ffff:", NULL },
	{ 6, "3049:1::8007:2040/0000:ffff::0", NULL },
	{ 6, "3049:1::8007:2040/ff1f:0", NULL },
	{ 6, "3049:1::8007:x:2040/128", NULL },
	{ 6, "3049:1t::8007:2040/128", NULL },
	{ 6, "3049:1::80071:2040/128", NULL },
	{ 6, "::/21", "::/21" },
	{ 6, "::1/128", "::1/128" },
	{ 6, "1::/21", "1::/21" },
	{ 6, "1::2/128", "1::2/128" },
	{ 6, "1:0:0:0:0:0:0:2/128", "1::2/128" },
	{ 6, "1:0:0:0:3:0:0:2/128", "1::3:0:0:2/128" },
	{ 6, "1:0:0:3:0:0:0:2/128", "1::3:0:0:0:2/128" },
	{ 6, "1:0:3:0:0:0:0:2/128", "1:0:3::2/128" },
	{ 6, "abcd:ef01:2345:6789:0:00a:000:20/128",
		"abcd:ef01:2345:6789:0:a:0:20/128" },
	{ 6, "3049:1::8007:2040/ffff:ffff:", NULL },
	{ 6, "3049:1::8007:2040/ffff:88:", NULL },
	{ 6, "3049:12::9000:3200/ffff:fff0", NULL },
	{ 6, "3049:12::9000:3200/28", "3049:10::/28" },
	{ 6, "3049:12::9000:3200/ff00:", NULL },
	{ 6, "3049:12::9000:3200/ffff:", NULL },
	{ 6, "3049:12::9000:3200/128_", NULL },
	{ 6, "3049:12::9000:3200/", NULL },
	{ 6, "%default", "::/0" },
	{ 4, NULL, NULL }
};

void regress(void)
{
	struct rtab *r;
	int status = 0;
	ip_subnet s;
	char in[100];
	char buf[100];
	const char *oops;
	size_t n;
	int af;

	for (r = rtab; r->input != NULL; r++) {
		af = (r->family == 4) ? AF_INET : AF_INET6;
		strcpy(in, r->input);
		printf("Testing `%s' ... ", in);
		oops = ttosubnet(in, 0, af, &s);
		if (oops != NULL && r->output == NULL)
			/* Error was expected, do nothing */
			printf("OK (%s)\n", oops);
		if (oops == NULL && r->output != NULL)
			/* No error, no error expected */
			printf("OK\n");
		if (oops == NULL && r->output == NULL) {
			/* If no errors, but we expected one */
			printf("`%s' ttosubnet succeeded unexpectedly\n",
				r->input);
			status = 1;
		}
		if (oops != NULL && r->output != NULL) {
			/* Error occurred, but we didn't expect one  */
			printf("`%s' ttosubnet failed: %s\n", r->input, oops);
			status = 1;
			n = subnetporttot(&s, 0, buf, sizeof(buf));
			if (n > sizeof(buf))
				printf("`%s' subnettot failed:  need %ld\n",
					r->input, (long)n);
			else if (!streq(r->output, buf))
				printf("`%s' gave `%s', expected `%s'\n",
					r->input, buf, r->output);
		}
	}
	exit(status);
}

#endif	/* TTOSUBNET_MAIN */