source: mainline/uspace/lib/c/generic/net/inet.c@ e4554d4

/*
 * Copyright (c) 2009 Lukas Mejdrech
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - 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.
 */

/** @addtogroup libc
 *  @{
 */

/** @file
 * Internet protocol address conversion functions implementation.
 */

#include <net/socket_codes.h>
#include <net/in.h>
#include <net/in6.h>
#include <net/inet.h>

#include <errno.h>
#include <mem.h>
#include <stdio.h>
#include <str.h>

/** Prints the address into the character buffer.
 *
 *  @param[in] family   The address family.
 *  @param[in] data     The address data.
 *  @param[out] address The character buffer to be filled.
 *  @param[in] length   The buffer length.
 *  @returns            EOK on success.
 *  @returns            EINVAL if the data or address parameter is NULL.
 *  @returns            ENOMEM if the character buffer is not long enough.
 *  @returns            ENOTSUP if the address family is not supported.
 */
int
inet_ntop(uint16_t family, const uint8_t *data, char *address, size_t length)
{
        if ((!data) || (!address))
                return EINVAL;

        switch (family) {
        case AF_INET:
                // check the output buffer size
                if (length < INET_ADDRSTRLEN)
                        return ENOMEM;
                        
                // fill the buffer with the IPv4 address
                snprintf(address, length, "%hhu.%hhu.%hhu.%hhu",
                    data[0], data[1], data[2], data[3]);

                return EOK;

        case AF_INET6:
                // check the output buffer size
                if (length < INET6_ADDRSTRLEN)
                        return ENOMEM;
                
                // fill the buffer with the IPv6 address
                snprintf(address, length,
                    "%hhx%hhx:%hhx%hhx:%hhx%hhx:%hhx%hhx:%hhx%hhx:%hhx%hhx:"
                    "%hhx%hhx:%hhx%hhx",
                    data[0], data[1], data[2], data[3], data[4], data[5],
                    data[6], data[7], data[8], data[9], data[10], data[11],
                    data[12], data[13], data[14], data[15]);
                
                return EOK;

        default:
                return ENOTSUP;
        }
}

/** Parses the character string into the address.
 *
 *  If the string is shorter than the full address, zero bytes are added.
 *
 *  @param[in] family   The address family.
 *  @param[in] address  The character buffer to be parsed.
 *  @param[out] data    The address data to be filled.
 *  @returns            EOK on success.
 *  @returns            EINVAL if the data parameter is NULL.
 *  @returns            ENOENT if the address parameter is NULL.
 *  @returns            ENOTSUP if the address family is not supported.
 */
int inet_pton(uint16_t family, const char *address, uint8_t *data)
{
        /** The base number of the values. */
        int base;
        /** The number of bytes per a section. */
        size_t bytes;
        /** The number of bytes of the address data. */
        int count;

        const char *next;
        char *last;
        int index;
        size_t shift;
        unsigned long value;

        if (!data)
                return EINVAL;

        // set the processing parameters
        switch (family) {
        case AF_INET:
                count = 4;
                base = 10;
                bytes = 1;
                break;

        case AF_INET6:
                count = 16;
                base = 16;
                bytes = 4;
                break;

        default:
                return ENOTSUP;
        }

        // erase if no address
        if (!address) {
                bzero(data, count);
                return ENOENT;
        }

        // process the string from the beginning
        next = address;
        index = 0;
        do {
                // if the actual character is set
                if (next && *next) {

                        // if not on the first character
                        if (index) {
                                // move to the next character
                                ++next;
                        }

                        // parse the actual integral value
                        value = strtoul(next, &last, base);
                        // remember the last problematic character
                        // should be either '.' or ':' but is ignored to be more
                        // generic
                        next = last;

                        // fill the address data byte by byte
                        shift = bytes - 1;
                        do {
                                // like little endian
                                data[index + shift] = value;
                                value >>= 8;
                        } while(shift --);

                        index += bytes;
                } else {
                        // erase the rest of the address
                        bzero(data + index, count - index);
                        return EOK;
                }
        } while (index < count);

        return EOK;
}

/** @}
 */