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#include "ipv6.h"
#include "ipv4.h"
static int hex2bin(char c)
{
switch (c) {
case '0': return 0x0;
case '1': return 0x1;
case '2': return 0x2;
case '3': return 0x3;
case '4': return 0x4;
case '5': return 0x5;
case '6': return 0x6;
case '7': return 0x7;
case '8': return 0x8;
case '9': return 0x9;
case 'A': case 'a': return 0xa;
case 'B': case 'b': return 0xb;
case 'C': case 'c': return 0xc;
case 'D': case 'd': return 0xd;
case 'E': case 'e': return 0xe;
case 'F': case 'f': return 0xf;
default: return -1;
}
}
static const char* parse_hexpart(const char* s, uint16* num)
{
int i = 0;
int t;
while ((t = hex2bin(*s)) != -1) {
++s;
i = (i << 4) | t;
if (i > 0xffff)
return 0;
}
*num = i;
return s;
}
static void set(ipv6addr* addr, int offset, uint16 bit)
{
offset *= 2;
addr->addr[offset++] = bit >> 8;
addr->addr[offset] = bit;
}
/** Scan a C string for an IPv6 address.
\return \c NULL if parsing failed, otherwise a pointer to the
first character after the end of the address.
*/
const char* ipv6_scan(const char* s, ipv6addr* addr)
{
uint16 bits[8];
unsigned len1;
unsigned len2;
unsigned i;
len1 = len2 = 0;
if (s[0] == ':' && s[1] == ':')
++s;
else {
while (len1 < 8) {
const char* news;
if ((news = parse_hexpart(s, &bits[len1])) == 0 ||
(news == s && *news != ':'))
return 0;
s = news + (*news == ':');
++len1;
if (*s == ':')
break;
}
for (i = 0; i < len1; ++i)
set(addr, i, bits[i]);
}
if (len1 < 8) {
++s;
while (len2 < 8-len1) {
const char* news;
if ((news = parse_hexpart(s, &bits[len2])) == 0)
return 0;
if (news == s) break;
s = news;
++len2;
if (*s != ':') break;
++s;
}
for (i = len1; i < 8-len2; ++i)
set(addr, i, 0);
for (i = 0; i < len2; ++i)
set(addr, i+8-len2, bits[i]);
}
/* handle IPv4 convenience addresses */
if (len1+len2 <= 6 && *s == '.') {
ipv4addr i4;
while (*--s != ':') ;
++s;
--len2;
for (i = len1; i < 6-len2; ++i)
set(addr, i, 0);
for (i = 0; i < len2; ++i)
set(addr, i+6-len2, bits[i]);
// Parse IPv4 address here
if ((s = ipv4_scan(s, &i4)) == 0)
return 0;
addr->addr[12] = i4.addr[0];
addr->addr[13] = i4.addr[1];
addr->addr[14] = i4.addr[2];
addr->addr[15] = i4.addr[3];
}
return s;
}
#ifdef SELFTEST_MAIN
static void test(const char* start)
{
ipv6addr ip;
int i;
const char* end;
obuf_put2s(&outbuf, start, "=");
end = ipv6_scan(start, &ip);
if (end == 0)
obuf_puts(&outbuf, "NULL");
else {
for (i = 0; i < 16; ++i) {
obuf_putxw(&outbuf, ip.addr[i], 2, '0');
}
obuf_putc(&outbuf, '+');
if (*end != 0)
obuf_puts(&outbuf, end);
}
NL();
obuf_flush(&outbuf);
}
MAIN
{
test("::");
test("::1");
test("::0.0.0.2");
test("::FFFF:1.20.100.200");
test("::FFFF:1.20.100.200x");
test("::101:0:0:0:0:0");
test("1080::8:800:200C:417A");
test("FF01::101");
test("FF01::");
test("FF01::x");
test("112:2334:4556:6778:899A:ABBC:CDDE:EFF0");
test("112:2334:4556:6778:899A:ABBC:CDDE:EFF0x");
}
#endif
#ifdef SELFTEST_EXP
::=00000000000000000000000000000000+
::1=00000000000000000000000000000001+
::0.0.0.2=00000000000000000000000000000002+
::FFFF:1.20.100.200=00000000000000000000ffff011464c8+
::FFFF:1.20.100.200x=00000000000000000000ffff011464c8+x
::101:0:0:0:0:0=00000000010100000000000000000000+
1080::8:800:200C:417A=108000000000000000080800200c417a+
FF01::101=ff010000000000000000000000000101+
FF01::=ff010000000000000000000000000000+
FF01::x=ff010000000000000000000000000000+x
112:2334:4556:6778:899A:ABBC:CDDE:EFF0=0112233445566778899aabbccddeeff0+
112:2334:4556:6778:899A:ABBC:CDDE:EFF0x=0112233445566778899aabbccddeeff0+x
#endif
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