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hbeberman merged 1 commit into from
Oct 22, 2020
+105 −2
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Patch gnutls CVE-2020-24659 #247

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97 changes: 97 additions & 0 deletions SPECS/gnutls/CVE-2020-24659.patch
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@@ -0,0 +1,97 @@
diff --git a/fuzz/gnutls_client_fuzzer.in/00ea40761ce11e769f1817a04b3d3f7dcc0ab4571cf0df3b67ab7e1005e9e7a8 b/fuzz/gnutls_client_fuzzer.in/00ea40761ce11e769f1817a04b3d3f7dcc0ab4571cf0df3b67ab7e1005e9e7a8
new file mode 100644
index 0000000000000000000000000000000000000000..73a2d97ba20483dc4f8c7766a043cb737e27c942
Binary files /dev/null and b/fuzz/gnutls_client_fuzzer.in/00ea40761ce11e769f1817a04b3d3f7dcc0ab4571cf0df3b67ab7e1005e9e7a8 differ
diff --git a/fuzz/gnutls_psk_client_fuzzer.in/b16434290b77e13d7a983d1da801fb3c6d1f7f846f227721e221adea08aa319c b/fuzz/gnutls_psk_client_fuzzer.in/b16434290b77e13d7a983d1da801fb3c6d1f7f846f227721e221adea08aa319c
new file mode 100644
index 0000000000000000000000000000000000000000..7ebb883f4d4c3401f32834f3bcc725d2404996f5
Binary files /dev/null and b/fuzz/gnutls_psk_client_fuzzer.in/b16434290b77e13d7a983d1da801fb3c6d1f7f846f227721e221adea08aa319c differ
diff --git a/lib/gnutls_int.h b/lib/gnutls_int.h
index bb6c19713851e1f59f98237b587deb86429ad0e0..31cec5c0cddbe2562d726368bebc5bba224f534c 100644
--- a/lib/gnutls_int.h
+++ b/lib/gnutls_int.h
@@ -1370,6 +1370,7 @@ typedef struct {
#define HSK_RECORD_SIZE_LIMIT_RECEIVED (1<<26) /* server: record_size_limit extension was seen but not accepted yet */
#define HSK_OCSP_REQUESTED (1<<27) /* server: client requested OCSP stapling */
#define HSK_CLIENT_OCSP_REQUESTED (1<<28) /* client: server requested OCSP stapling */
+#define HSK_SERVER_HELLO_RECEIVED (1<<29) /* client: Server Hello message has been received */

/* The hsk_flags are for use within the ongoing handshake;
* they are reset to zero prior to handshake start by gnutls_handshake. */
diff --git a/lib/handshake.c b/lib/handshake.c
index b40f84b3d972057be1c2dccdbc2f4fc4ab2948a8..ce2d160e2077c6d971de58e63ec86b9b035af853 100644
--- a/lib/handshake.c
+++ b/lib/handshake.c
@@ -2061,6 +2061,8 @@ read_server_hello(gnutls_session_t session,
if (ret < 0)
return gnutls_assert_val(ret);

+ session->internals.hsk_flags |= HSK_SERVER_HELLO_RECEIVED;
+
return 0;
}

@@ -2585,16 +2587,42 @@ int gnutls_rehandshake(gnutls_session_t session)
return 0;
}

+/* This function checks whether the error code should be treated fatal
+ * or not, and also does the necessary state transition. In
+ * particular, in the case of a rehandshake abort it resets the
+ * handshake's internal state.
+ */
inline static int
_gnutls_abort_handshake(gnutls_session_t session, int ret)
{
- if (((ret == GNUTLS_E_WARNING_ALERT_RECEIVED) &&
- (gnutls_alert_get(session) == GNUTLS_A_NO_RENEGOTIATION))
- || ret == GNUTLS_E_GOT_APPLICATION_DATA)
- return 0;
+ switch (ret) {
+ case GNUTLS_E_WARNING_ALERT_RECEIVED:
+ if (gnutls_alert_get(session) == GNUTLS_A_NO_RENEGOTIATION) {
+ /* The server always toleretes a "no_renegotiation" alert. */
+ if (session->security_parameters.entity == GNUTLS_SERVER) {
+ STATE = STATE0;
+ return ret;
+ }
+
+ /* The client should tolerete a "no_renegotiation" alert only if:
+ * - the initial handshake has completed, or
+ * - a Server Hello is not yet received
+ */
+ if (session->internals.initial_negotiation_completed ||
+ !(session->internals.hsk_flags & HSK_SERVER_HELLO_RECEIVED)) {
+ STATE = STATE0;
+ return ret;
+ }

- /* this doesn't matter */
- return GNUTLS_E_INTERNAL_ERROR;
+ return gnutls_assert_val(GNUTLS_E_UNEXPECTED_PACKET);
+ }
+ return ret;
+ case GNUTLS_E_GOT_APPLICATION_DATA:
+ STATE = STATE0;
+ return ret;
+ default:
+ return ret;
+ }
}


@@ -2756,13 +2784,7 @@ int gnutls_handshake(gnutls_session_t session)
}

if (ret < 0) {
- /* In the case of a rehandshake abort
- * we should reset the handshake's internal state.
- */
- if (_gnutls_abort_handshake(session, ret) == 0)
- STATE = STATE0;
-
- return ret;
+ return _gnutls_abort_handshake(session, ret);
}

/* clear handshake buffer */
10 changes: 8 additions & 2 deletions SPECS/gnutls/gnutls.spec
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Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
Summary: The GnuTLS Transport Layer Security Library
Name: gnutls
Version: 3.6.14
Release: 2%{?dist}
Release: 3%{?dist}
License: GPLv3+ and LGPLv2+
URL: https://www.gnutls.org
Source0: ftp://ftp.gnutls.org/gcrypt/gnutls/v3.6/%{name}-%{version}.tar.xz
Expand All @@ -22,6 +22,8 @@ Requires: gmp
Requires: guile
Requires: gc

Patch0: CVE-2020-24659.patch

%description
GnuTLS is a secure communications library implementing the SSL, TLS and DTLS protocols and technologies around them. It provides a simple C language application programming interface (API) to access the secure communications protocols as well as APIs to parse and write X.509, PKCS #12, OpenPGP and other required structures. It is aimed to be portable and efficient with focus on security and interoperability.

Expand All @@ -36,7 +38,8 @@ The package contains libraries and header files for
developing applications that use gnutls.

%prep
%setup -q
%autosetup -p1

%build

%configure \
Expand Down Expand Up @@ -88,6 +91,9 @@ make %{?_smp_mflags} check
%{_mandir}/man3/*

%changelog
* Wed Oct 21 2020 Henry Beberman <henry.beberman@microsoft.com> 3.6.14-3
- Apply patch for CVE-2020-24659 from upstream.
- Switch setup to autosetup.
* Wed Oct 07 2020 Pawel Winogrodzki <pawelwi@microsoft.com> 3.6.14-2
- Updating certificate bundle path to include full set of trust information.
* Fri Aug 21 2020 Andrew Phelps <anphel@microsoft.com> 3.6.14-1
Expand Down