From c46dc5cc0499a41c6ad08ae32bee45568ab37da6 Mon Sep 17 00:00:00 2001 From: mandree Date: Sat, 1 Jun 2013 16:47:41 +0000 Subject: - Backport fix for CVE-2013-2061 to openvpn22 and openvpn20; while it is unclear whether it affects OpenSSL-builds at all. Let's play it safe. - Reference CVE-2013-2061 name in OpenVPN's VuXML entry - Mark 2.0.9_4 <= openvpn < 2.1.0 and 2.2.2_2 < openvpn < 2.3.0 not vulnerable - Mark openvpn22 deprecated and to expire 2013-09-01. (openvpn20 is already marked to expire 2013-07-11.) Security: CVE-2013-2061 Security: 92f30415-9935-11e2-ad4c-080027ef73ec --- security/openvpn20/Makefile | 2 +- security/openvpn20/files/patch-CVE-2013-2061 | 74 ++++++++++++++++++++++++++++ 2 files changed, 75 insertions(+), 1 deletion(-) create mode 100644 security/openvpn20/files/patch-CVE-2013-2061 (limited to 'security/openvpn20') diff --git a/security/openvpn20/Makefile b/security/openvpn20/Makefile index 6d3b0cdcb587..4ee0e963858a 100644 --- a/security/openvpn20/Makefile +++ b/security/openvpn20/Makefile @@ -3,7 +3,7 @@ PORTNAME= openvpn PORTVERSION= 2.0.9 -PORTREVISION= 3 +PORTREVISION= 4 CATEGORIES= security net # MASTER_SITES points to hosts in distinct data centers, # so just one MASTER_SITES entry should be OK. diff --git a/security/openvpn20/files/patch-CVE-2013-2061 b/security/openvpn20/files/patch-CVE-2013-2061 new file mode 100644 index 000000000000..fc622b37a131 --- /dev/null +++ b/security/openvpn20/files/patch-CVE-2013-2061 @@ -0,0 +1,74 @@ +commit 11d21349a4e7e38a025849479b36ace7c2eec2ee +Author: Steffan Karger +Date: Tue Mar 19 13:01:50 2013 +0100 + + Use constant time memcmp when comparing HMACs in openvpn_decrypt. + + Signed-off-by: Steffan Karger + Acked-by: Gert Doering + Signed-off-by: Gert Doering + +diff --git a/src/openvpn/buffer.h b/src/openvpn/buffer.h +index 7cae733..93efb09 100644 +--- ./buffer.h~ ++++ ./buffer.h +@@ -668,6 +668,10 @@ buf_read_u32 (struct buffer *buf, bool *good) + } + } + ++/** ++ * Compare src buffer contents with match. ++ * *NOT* constant time. Do not use when comparing HMACs. ++ */ + static inline bool + buf_string_match (const struct buffer *src, const void *match, int size) + { +@@ -676,6 +680,10 @@ buf_string_match (const struct buffer *src, const void *match, int size) + return memcmp (BPTR (src), match, size) == 0; + } + ++/** ++ * Compare first size bytes of src buffer contents with match. ++ * *NOT* constant time. Do not use when comparing HMACs. ++ */ + static inline bool + buf_string_match_head (const struct buffer *src, const void *match, int size) + { +diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c +index 405c0aa..d9adf5b 100644 +--- ./crypto.c~ ++++ ./crypto.c +@@ -65,6 +65,24 @@ + #define CRYPT_ERROR(format) \ + do { msg (D_CRYPT_ERRORS, "%s: " format, error_prefix); goto error_exit; } while (false) + ++/** ++ * As memcmp(), but constant-time. ++ * Returns 0 when data is equal, non-zero otherwise. ++ */ ++static int ++memcmp_constant_time (const void *a, const void *b, size_t size) { ++ const uint8_t * a1 = a; ++ const uint8_t * b1 = b; ++ int ret = 0; ++ size_t i; ++ ++ for (i = 0; i < size; i++) { ++ ret |= *a1++ ^ *b1++; ++ } ++ ++ return ret; ++} ++ + void + openvpn_encrypt (struct buffer *buf, struct buffer work, + const struct crypto_options *opt, +@@ -244,7 +262,7 @@ openvpn_decrypt (struct buffer *buf, struct buffer work, + hmac_ctx_final (ctx->hmac, local_hmac); + + /* Compare locally computed HMAC with packet HMAC */ +- if (memcmp (local_hmac, BPTR (buf), hmac_len)) ++ if (memcmp_constant_time (local_hmac, BPTR (buf), hmac_len)) + CRYPT_ERROR ("packet HMAC authentication failed"); + + ASSERT (buf_advance (buf, hmac_len)); -- cgit