mbed-os/features/FEATURE_COMMON_PAL/nanostack-libservice/source/libip6string/stoip6.c

99 lines
3.1 KiB
C

/*
* Copyright (c) 2014-2015 ARM Limited. All rights reserved.
* SPDX-License-Identifier: Apache-2.0
* Licensed under the Apache License, Version 2.0 (the License); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an AS IS BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#include "common_functions.h"
#include "ip6string.h"
static uint16_t hex(const char *p);
/**
* Convert numeric IPv6 address string to a binary.
* IPv4 tunnelling addresses are not covered.
* \param ip6addr IPv6 address in string format.
* \param len Length of ipv6 string.
* \param dest buffer for address. MUST be 16 bytes.
*/
void stoip6(const char *ip6addr, size_t len, void *dest)
{
uint8_t *addr;
const char *p, *q;
int_fast8_t field_no, coloncolon = -1;
addr = dest;
if (len > 39) { // Too long, not possible. We do not support IPv4-mapped IPv6 addresses
return;
}
// First go forward the string, until end, noting :: position if any
for (field_no = 0, p = ip6addr; (len > (p - ip6addr)) && *p && field_no < 8; p = q + 1) {
q = p;
// Seek for ':' or end
while (*q && (*q != ':')) {
q++;
}
//Convert and write this part, (high-endian AKA network byte order)
addr = common_write_16_bit(hex(p), addr);
field_no++;
//Check if we reached "::"
if ((len > (q - ip6addr)) && *q && (q[0] == ':') && (q[1] == ':')) {
coloncolon = field_no;
q++;
}
}
if (coloncolon != -1) {
/* Insert zeros in the appropriate place */
uint_fast8_t head_size = 2 * coloncolon;
uint_fast8_t inserted_size = 2 * (8 - field_no);
uint_fast8_t tail_size = 16 - head_size - inserted_size;
addr = dest;
memmove(addr + head_size + inserted_size, addr + head_size, tail_size);
memset(addr + head_size, 0, inserted_size);
} else if (field_no != 8) {
/* Should really report an error if we didn't get 8 fields */
memset(addr, 0, 16 - field_no * 2);
}
}
unsigned char sipv6_prefixlength(const char *ip6addr)
{
char *ptr = strchr(ip6addr, '/');
if (ptr) {
return (unsigned char)strtoul(ptr + 1, 0, 10);
}
return 0;
}
static uint16_t hex(const char *p)
{
uint16_t val = 0;
for (;;) {
char c = *p++;
if ((c >= '0') && (c <= '9')) {
val = (val << 4) | (c - '0');
} else if ((c >= 'A') && (c <= 'F')) {
val = (val << 4) | (10 + (c - 'A'));
} else if ((c >= 'a') && (c <= 'f')) {
val = (val << 4) | (10 + (c - 'a'));
} else {
break; // Non hex character
}
}
return val;
}