/*      $NetBSD: type_ipv4.c,v 1.11 2016/03/09 19:47:13 christos Exp $  */

/*-
 * Copyright (c) 1998-1999 Brett Lymn
 *                         (blymn@baea.com.au, brett_lymn@yahoo.com.au)
 * All rights reserved.
 *
 * This code has been donated to The NetBSD Foundation by the Author.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *
 */

#include <sys/cdefs.h>
__RCSID("$NetBSD: type_ipv4.c,v 1.11 2016/03/09 19:47:13 christos Exp $");

#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include "form.h"
#include "internals.h"

/*
 * The IP v4 address type handling.
 */

/*
 * define the styles of address we can have, they are:
 *    FORMI_DOTTED_QUAD    address of form aaa.bbb.ccc.ddd
 *    FORMI_HEX            address of form 0xaabbccdd
 *    FORMI_CLASSLESS      address of form aaa.bbb.ccc.ddd/ee
 */
#define FORMI_DOTTED_QUAD  0
#define FORMI_HEX          1
#define FORMI_CLASSLESS    2

/*
 * Check the contents of the field buffer are a valid IPv4 address only.
 */
static int
ipv4_check_field(FIELD *field, char *args)
{
        char *buf, *buf1, *keeper, *p, *slash;
        unsigned int vals[4], style, start, mask;
        unsigned long hex_val, working;
        int i;

        if (args == NULL)
                return FALSE;
        
        if (asprintf(&keeper, "%s", args) < 0)
                return FALSE;

#ifdef DEBUG
        _formi_dbg_printf("%s: enter with args of %s\n", __func__, keeper);
#endif
        style = FORMI_DOTTED_QUAD;
        buf = keeper;
        hex_val = 0;
        mask = 0;
        
        if ((slash = index(buf, '/')) != NULL)
                style = FORMI_CLASSLESS;
        else {
                start = _formi_skip_blanks(buf, 0);
                if ((buf[start] != '\0') && (buf[start + 1] != '\0') &&
                    (buf[start] == '0') && ((buf[start + 1] == 'x') ||
                                            (buf[start + 1] == 'X')))
                        style = FORMI_HEX;
        }

        switch (style) {
        case FORMI_CLASSLESS:
                *slash = '\0';
                slash++;
                mask = atoi(slash);
                if (mask > 32)
                        goto FAIL;
                  /* FALLTHROUGH */
                
        case FORMI_DOTTED_QUAD:
                for (i = 0; i < 4; i++) {
                        p = strsep(&buf, ".");
                        if ((p == NULL) || (*p == '\0'))
                                goto FAIL;
                        vals[i] = atoi(p);
                        if (vals[i] > 255)
                                goto FAIL;
                }
                break;

                
        case FORMI_HEX:
                errno = 0;
                hex_val = strtoul(buf, NULL, 16);
                if ((hex_val == ULONG_MAX) && (errno == ERANGE))
                        goto FAIL;
                
                working = hex_val;
                for (i = 3; i >= 0; i--) {
                        vals[i] = (unsigned int)(working & 0xffUL);
                        working = working >> 8;
                }
                break;

        }
        
        free(keeper);

        buf1 = NULL;
        
        switch (style) {
        case FORMI_DOTTED_QUAD:
                if (asprintf(&buf, "%d.%d.%d.%d", vals[0], vals[1], vals[2],
                             vals[3]) < 0)
                        return FALSE;
                if (asprintf(&buf1, "%d.%d.%d.%d", vals[0], vals[1],
                             vals[2], vals[3]) < 0)
                        return FALSE;
                break;

        case FORMI_CLASSLESS:
                if (asprintf(&buf, "%d.%d.%d.%d/%d", vals[0], vals[1],
                             vals[2], vals[3], mask) < 0)
                        return FALSE;
                if (asprintf(&buf1, "%d.%d.%d.%d", vals[0], vals[1],
                             vals[2], vals[3]) < 0)
                        return FALSE;
                break;

        case FORMI_HEX:
                if (asprintf(&buf, "0x%.8lx", hex_val) < 0)
                        return FALSE;
                if (asprintf(&buf1, "%d.%d.%d.%d", vals[0], vals[1],
                             vals[2], vals[3]) < 0)
                        return FALSE;
                break;
        }
        
          /* re-set the field buffer to be the reformatted IPv4 address */
        set_field_buffer(field, 0, buf);

          /*
           * Set the field buffer 1 to the dotted quad format regardless
           * of the input format, only if buffer 1 exists.
           */
        if (field->nbuf > 1)
                set_field_buffer(field, 1, buf1);

#ifdef DEBUG
        _formi_dbg_printf("%s: buf0 set to %s\n", __func__, buf);
        _formi_dbg_printf("%s: buf1 set to %s\n", __func__, buf1);
#endif
        free(buf);
        free(buf1);
        
        return TRUE;

          /* bail out point if we got a bad entry */
  FAIL:
        free(keeper);
        return FALSE;
        
}

/*
 * Check the given character is numeric, return TRUE if it is.
 */
static int
ipv4_check_char(/* ARGSUSED1 */ int c, char *args)
{
        return (isxdigit(c) || (c == '.') || (tolower(c) == 'x') ||
                (c == '/'))? TRUE : FALSE;
}

static FIELDTYPE builtin_ipv4 = {
        _TYPE_IS_BUILTIN,                   /* flags */
        0,                                  /* refcount */
        NULL,                               /* link */
        NULL,                               /* make_args */
        NULL,                               /* copy_args */
        NULL,                               /* free_args */
        ipv4_check_field,                   /* field_check */
        ipv4_check_char,                    /* char_check */
        NULL,                               /* next_choice */
        NULL                                /* prev_choice */
};

FIELDTYPE *TYPE_IPV4 = &builtin_ipv4;