/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * This file contains a routine used to validate a ifconfig-style interface
 * specification
 */

#include <stdlib.h>
#include <ctype.h>
#include <alloca.h>
#include <errno.h>
#include <string.h>
#include <libinetutil.h>

/*
 * Given a token with a logical unit spec, return the logical unit converted
 * to a uint_t.
 *
 * Returns: 0 for success, nonzero if an error occurred. errno is set if
 * necessary.
 */
static int
getlun(const char *bp, int bpsize, uint_t *lun)
{
        char    *ep = (char *)&bp[bpsize - 1];
        char    *sp = strchr(bp, ':'), *tp;

        /* A logical unit spec looks like: <token>:<unsigned int>\0 */
        if (isdigit(*bp) || !isdigit(*ep) || sp == NULL ||
            strchr(sp + 1, ':') != NULL) {
                errno = EINVAL;
                return (-1);
        }

        *sp++ = '\0';

        /* Lun must be all digits */
        for (tp = sp; tp < ep && isdigit(*tp); tp++)
                /* Null body */;
        if (tp != ep) {
                errno = EINVAL;
                return (-1);
        }

        *lun = atoi(sp);
        return (0);
}

/*
 * Given a single token ending with a ppa spec, return the ppa spec converted
 * to a uint_t.
 *
 * Returns: 0 for success, nonzero if an error occurred. errno is set if
 * necessary.
 */
static int
getppa(const char *bp, int bpsize, uint_t *ppa)
{
        char    *ep = (char *)&bp[bpsize - 1];
        char    *tp;

        if (!isdigit(*ep)) {
                errno = EINVAL;
                return (-1);
        }

        for (tp = ep; tp >= bp && isdigit(*tp); tp--)
                /* Null body */;

        if (*tp == ':') {
                errno = EINVAL;
                return (-1);
        }

        *ppa = atoi(tp + 1);
        return (0);
}

/*
 * Given an ifconfig-style inet relative-path interface specification
 * (e.g: bge0:2), validate its form and decompose the contents into a
 * dynamically allocated ifspec_t.
 *
 * Returns ifspec_t for success, NULL pointer if spec is malformed.
 */
boolean_t
ifparse_ifspec(const char *ifname, ifspec_t *ifsp)
{
        char    *lp, *tp;
        char    ifnamecp[LIFNAMSIZ];

        /* snag a copy we can modify */
        if (strlcpy(ifnamecp, ifname, LIFNAMSIZ) >= LIFNAMSIZ) {
                errno = EINVAL;
                return (B_FALSE);
        }

        ifsp->ifsp_lunvalid = B_FALSE;

        /*
         * An interface name must have the format of:
         * dev[ppa][:lun]
         *
         * lun - logical unit number.
         */

        /* Any logical units? */
        lp = strchr(ifnamecp, ':');
        if (lp != NULL) {
                if (getlun(lp, strlen(lp), &ifsp->ifsp_lun) != 0)
                        return (B_FALSE);
                ifsp->ifsp_lunvalid = B_TRUE;
        }

        (void) strlcpy(ifsp->ifsp_devnm, ifnamecp, LIFNAMSIZ);

        /* Find ppa  */
        if (getppa(ifsp->ifsp_devnm, strlen(ifsp->ifsp_devnm),
            &ifsp->ifsp_ppa) != 0) {
                return (B_FALSE);
        }

        /* strip the ppa off of the device name if present */
        for (tp = &ifsp->ifsp_devnm[strlen(ifsp->ifsp_devnm) - 1];
            tp >= ifsp->ifsp_devnm && isdigit(*tp); tp--) {
                *tp = '\0';
        }

        return (B_TRUE);
}