inet_pton: Reject IPv6 addresses with many leading zeros [BZ #16637]

2001:db8:00001::f is not a valid IPv6 address according to RFC 2373.
This commit is contained in:
Florian Weimer 2017-06-23 22:51:00 +02:00
parent fa872e1b62
commit 9a0cc8c1bd
3 changed files with 20 additions and 21 deletions

View File

@ -1,3 +1,11 @@
2017-06-23 Florian Weimer <fweimer@redhat.com>
[BZ #16637]
inet_pton: Reject invalid IPv6 addresses with many leading zeros.
* resolv/inet_pton.c (inet_pton6): Count number of hexadecimal
digits between colons.
* resolv/tst-inet_pton.c (test_cases): Adjust test expectations.
2017-05-23 Adhemerval Zanella <adhemerval.zanella@linaro.org>
Juan Manuel Torres Palma <jmtorrespalma@gmail.com>

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@ -144,7 +144,8 @@ inet_pton6 (const char *src, const char *src_endp, unsigned char *dst)
{
unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
const char *curtok;
int ch, saw_xdigit;
int ch;
size_t xdigits_seen; /* Number of hex digits since colon. */
unsigned int val;
tp = memset (tmp, '\0', NS_IN6ADDRSZ);
@ -162,7 +163,7 @@ inet_pton6 (const char *src, const char *src_endp, unsigned char *dst)
}
curtok = src;
saw_xdigit = 0;
xdigits_seen = 0;
val = 0;
while (src < src_endp)
{
@ -170,17 +171,19 @@ inet_pton6 (const char *src, const char *src_endp, unsigned char *dst)
int digit = hex_digit_value (ch);
if (digit >= 0)
{
if (xdigits_seen == 4)
return 0;
val <<= 4;
val |= digit;
if (val > 0xffff)
return 0;
saw_xdigit = 1;
++xdigits_seen;
continue;
}
if (ch == ':')
{
curtok = src;
if (!saw_xdigit)
if (xdigits_seen == 0)
{
if (colonp)
return 0;
@ -193,7 +196,7 @@ inet_pton6 (const char *src, const char *src_endp, unsigned char *dst)
return 0;
*tp++ = (unsigned char) (val >> 8) & 0xff;
*tp++ = (unsigned char) val & 0xff;
saw_xdigit = 0;
xdigits_seen = 0;
val = 0;
continue;
}
@ -201,12 +204,12 @@ inet_pton6 (const char *src, const char *src_endp, unsigned char *dst)
&& inet_pton4 (curtok, src_endp, tp) > 0)
{
tp += NS_INADDRSZ;
saw_xdigit = 0;
xdigits_seen = 0;
break; /* '\0' was seen by inet_pton4. */
}
return 0;
}
if (saw_xdigit)
if (xdigits_seen > 0)
{
if (tp + NS_INT16SZ > endp)
return 0;

View File

@ -226,13 +226,7 @@ const struct test_case test_cases[] =
},
{.input = "2", },
{.input = "2.", },
{.input = "2001:db8:00001::f",
.ipv6_ok = true,
.ipv6_expected = {
0x20, 0x1, 0xd, 0xb8, 0x0, 0x1, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xf
},
},
{.input = "2001:db8:00001::f", },
{.input = "2001:db8:10000::f", },
{.input = "2001:db8:1234:5678:abcd:ef01:2345:67",
.ipv6_ok = true,
@ -454,13 +448,7 @@ const struct test_case test_cases[] =
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0
},
},
{.input = "::00001",
.ipv6_ok = true,
.ipv6_expected = {
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1
},
},
{.input = "::00001", },
{.input = "::1",
.ipv6_ok = true,
.ipv6_expected = {