From 9a0cc8c1bd7645bf3c988890ffb59639c07a5812 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Fri, 23 Jun 2017 22:51:00 +0200 Subject: 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. --- ChangeLog | 8 ++++++++ resolv/inet_pton.c | 17 ++++++++++------- resolv/tst-inet_pton.c | 16 ++-------------- 3 files changed, 20 insertions(+), 21 deletions(-) diff --git a/ChangeLog b/ChangeLog index 9b055b421e..accdd06e1d 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2017-06-23 Florian Weimer + + [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 Juan Manuel Torres Palma diff --git a/resolv/inet_pton.c b/resolv/inet_pton.c index b95da47c17..16ee33e0c0 100644 --- a/resolv/inet_pton.c +++ b/resolv/inet_pton.c @@ -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; diff --git a/resolv/tst-inet_pton.c b/resolv/tst-inet_pton.c index 7fffb24cdf..4bb9f81193 100644 --- a/resolv/tst-inet_pton.c +++ b/resolv/tst-inet_pton.c @@ -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 = { -- cgit 1.4.1