]> git.ipfire.org Git - thirdparty/postgresql.git/commitdiff
Fix handling of SCRAM-SHA-256's channel binding with RSA-PSS certificates
authorMichael Paquier <michael@paquier.xyz>
Wed, 15 Feb 2023 01:12:31 +0000 (10:12 +0900)
committerMichael Paquier <michael@paquier.xyz>
Wed, 15 Feb 2023 01:12:31 +0000 (10:12 +0900)
OpenSSL 1.1.1 and newer versions have added support for RSA-PSS
certificates, which requires the use of a specific routine in OpenSSL to
determine which hash function to use when compiling it when using
channel binding in SCRAM-SHA-256.  X509_get_signature_nid(), that is the
original routine the channel binding code has relied on, is not able to
determine which hash algorithm to use for such certificates.  However,
X509_get_signature_info(), new to OpenSSL 1.1.1, is able to do it.  This
commit switches the channel binding logic to rely on
X509_get_signature_info() over X509_get_signature_nid(), which would be
the choice when building with 1.1.1 or newer.

The error could have been triggered on the client or the server, hence
libpq and the backend need to have their related code paths patched.
Note that attempting to load an RSA-PSS certificate with OpenSSL 1.1.0
or older leads to a failure due to an unsupported algorithm.

The discovery of relying on X509_get_signature_info() comes from Jacob,
the tests have been written by Heikki (with few tweaks from me), while I
have bundled the whole together while adding the bits needed for MSVC
and meson.

This issue exists since channel binding exists, so backpatch all the way
down.  Some tests are added in 15~, triggered if compiling with OpenSSL
1.1.1 or newer, where the certificate and key files can easily be
generated for RSA-PSS.

Reported-by: Gunnar "Nick" Bluth
Author: Jacob Champion, Heikki Linnakangas
Discussion: https://postgr.es/m/17760-b6c61e752ec07060@postgresql.org
Backpatch-through: 11

14 files changed:
configure
configure.ac
src/backend/libpq/be-secure-openssl.c
src/include/libpq/libpq-be.h
src/include/pg_config.h.in
src/interfaces/libpq/fe-secure-openssl.c
src/interfaces/libpq/libpq-int.h
src/test/ssl/README
src/test/ssl/conf/server-rsapss.config [new file with mode: 0644]
src/test/ssl/ssl/server-rsapss.crt [new file with mode: 0644]
src/test/ssl/ssl/server-rsapss.key [new file with mode: 0644]
src/test/ssl/sslfiles.mk
src/test/ssl/t/002_scram.pl
src/tools/msvc/Solution.pm

index 02a6add8e0a933717b288a983e624f2c476fc9f8..6c87ca479a87d0499e400cd4902b5d6a97a423dc 100755 (executable)
--- a/configure
+++ b/configure
@@ -13260,6 +13260,18 @@ if test "x$ac_cv_func_CRYPTO_lock" = xyes; then :
 #define HAVE_CRYPTO_LOCK 1
 _ACEOF
 
+fi
+done
+
+  # Function introduced in OpenSSL 1.1.1.
+  for ac_func in X509_get_signature_info
+do :
+  ac_fn_c_check_func "$LINENO" "X509_get_signature_info" "ac_cv_func_X509_get_signature_info"
+if test "x$ac_cv_func_X509_get_signature_info" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_X509_GET_SIGNATURE_INFO 1
+_ACEOF
+
 fi
 done
 
index 9a73f50c42874d7d5f72927609ee275842da3f87..01968035f3d41b68b2ec07dc97b04bf9c0037671 100644 (file)
@@ -1352,6 +1352,8 @@ if test "$with_ssl" = openssl ; then
   # thread-safety. In 1.1.0, it's no longer required, and CRYPTO_lock()
   # function was removed.
   AC_CHECK_FUNCS([CRYPTO_lock])
+  # Function introduced in OpenSSL 1.1.1.
+  AC_CHECK_FUNCS([X509_get_signature_info])
   AC_DEFINE([USE_OPENSSL], 1, [Define to 1 to build with OpenSSL support. (--with-ssl=openssl)])
 elif test "$with_ssl" != no ; then
   AC_MSG_ERROR([--with-ssl must specify openssl])
index 3d0168a36968295d4ada9dd72f43d1ceee152e79..8f9b81c71af52a42900bded1b10e37db8f5fa95c 100644 (file)
@@ -1320,7 +1320,7 @@ be_tls_get_peer_serial(Port *port, char *ptr, size_t len)
                ptr[0] = '\0';
 }
 
-#ifdef HAVE_X509_GET_SIGNATURE_NID
+#if defined(HAVE_X509_GET_SIGNATURE_NID) || defined(HAVE_X509_GET_SIGNATURE_INFO)
 char *
 be_tls_get_certificate_hash(Port *port, size_t *len)
 {
@@ -1338,10 +1338,15 @@ be_tls_get_certificate_hash(Port *port, size_t *len)
 
        /*
         * Get the signature algorithm of the certificate to determine the hash
-        * algorithm to use for the result.
+        * algorithm to use for the result.  Prefer X509_get_signature_info(),
+        * introduced in OpenSSL 1.1.1, which can handle RSA-PSS signatures.
         */
+#if HAVE_X509_GET_SIGNATURE_INFO
+       if (!X509_get_signature_info(server_cert, &algo_nid, NULL, NULL, NULL))
+#else
        if (!OBJ_find_sigid_algs(X509_get_signature_nid(server_cert),
                                                         &algo_nid, NULL))
+#endif
                elog(ERROR, "could not determine server certificate signature algorithm");
 
        /*
index 90c20da22bf6685987cbcfe4cd0795ced31b516a..351b4f4d971d01128f8902bcaa445f4043f44b7c 100644 (file)
@@ -300,7 +300,7 @@ extern void be_tls_get_peer_serial(Port *port, char *ptr, size_t len);
  * This is not supported with old versions of OpenSSL that don't have
  * the X509_get_signature_nid() function.
  */
-#if defined(USE_OPENSSL) && defined(HAVE_X509_GET_SIGNATURE_NID)
+#if defined(USE_OPENSSL) && (defined(HAVE_X509_GET_SIGNATURE_NID) || defined(HAVE_X509_GET_SIGNATURE_INFO))
 #define HAVE_BE_TLS_GET_CERTIFICATE_HASH
 extern char *be_tls_get_certificate_hash(Port *port, size_t *len);
 #endif
index cdd742cb55bf84718754dcc94c8d42008403013a..d09e9f9a1c3fa55cad86374c1f435d3e77eaa958 100644 (file)
 /* Define to 1 if you have the `writev' function. */
 #undef HAVE_WRITEV
 
+/* Define to 1 if you have the `X509_get_signature_info' function. */
+#undef HAVE_X509_GET_SIGNATURE_INFO
+
 /* Define to 1 if you have the `X509_get_signature_nid' function. */
 #undef HAVE_X509_GET_SIGNATURE_NID
 
index fe1e98a3b0d91b63e26eec649162639267b4637f..af59ff49f7060c7e9d25aa2693f40500590e2418 100644 (file)
@@ -380,7 +380,7 @@ pgtls_write(PGconn *conn, const void *ptr, size_t len)
        return n;
 }
 
-#ifdef HAVE_X509_GET_SIGNATURE_NID
+#if defined(HAVE_X509_GET_SIGNATURE_NID) || defined(HAVE_X509_GET_SIGNATURE_INFO)
 char *
 pgtls_get_peer_certificate_hash(PGconn *conn, size_t *len)
 {
@@ -400,10 +400,15 @@ pgtls_get_peer_certificate_hash(PGconn *conn, size_t *len)
 
        /*
         * Get the signature algorithm of the certificate to determine the hash
-        * algorithm to use for the result.
+        * algorithm to use for the result.  Prefer X509_get_signature_info(),
+        * introduced in OpenSSL 1.1.1, which can handle RSA-PSS signatures.
         */
+#if HAVE_X509_GET_SIGNATURE_INFO
+       if (!X509_get_signature_info(peer_cert, &algo_nid, NULL, NULL, NULL))
+#else
        if (!OBJ_find_sigid_algs(X509_get_signature_nid(peer_cert),
                                                         &algo_nid, NULL))
+#endif
        {
                appendPQExpBufferStr(&conn->errorMessage,
                                                         libpq_gettext("could not determine server certificate signature algorithm\n"));
index a27dd3785e11fd8bd333629f3a373a421ceb61cc..ac9042ffdcc4989b240d1dcf76e8df53c22374a2 100644 (file)
@@ -804,7 +804,7 @@ extern ssize_t pgtls_write(PGconn *conn, const void *ptr, size_t len);
  * This is not supported with old versions of OpenSSL that don't have
  * the X509_get_signature_nid() function.
  */
-#if defined(USE_OPENSSL) && defined(HAVE_X509_GET_SIGNATURE_NID)
+#if defined(USE_OPENSSL) && (defined(HAVE_X509_GET_SIGNATURE_NID) || defined(HAVE_X509_GET_SIGNATURE_INFO))
 #define HAVE_PGTLS_GET_PEER_CERTIFICATE_HASH
 extern char *pgtls_get_peer_certificate_hash(PGconn *conn, size_t *len);
 #endif
index 7e6070065204527b8dccee9dcedf1191e552438a..ff55697c0a033dcb840b7e4037b18823bf0e900d 100644 (file)
@@ -92,6 +92,7 @@ ssl/ subdirectory. The Makefile also contains a rule, "make sslfiles", to
 recreate them if you need to make changes. "make sslfiles-clean" is required
 in order to recreate the full set of keypairs and certificates. To rebuild
 separate files, touch (or remove) the files in question and run "make sslfiles".
+This step requires at least OpenSSL 1.1.1.
 
 TODO
 ====
diff --git a/src/test/ssl/conf/server-rsapss.config b/src/test/ssl/conf/server-rsapss.config
new file mode 100644 (file)
index 0000000..391f9b8
--- /dev/null
@@ -0,0 +1,14 @@
+# An OpenSSL format CSR config file for creating a server certificate.
+#
+# This is identical to server-cn-only certificate, but we specify
+# RSA-PSS as the algorithm on the command line.
+
+[ req ]
+distinguished_name     = req_distinguished_name
+prompt                 = no
+
+[ req_distinguished_name ]
+CN = common-name.pg-ssltest.test
+OU = PostgreSQL test suite
+
+# No Subject Alternative Names
\ No newline at end of file
diff --git a/src/test/ssl/ssl/server-rsapss.crt b/src/test/ssl/ssl/server-rsapss.crt
new file mode 100644 (file)
index 0000000..1c35956
--- /dev/null
@@ -0,0 +1,21 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/src/test/ssl/ssl/server-rsapss.key b/src/test/ssl/ssl/server-rsapss.key
new file mode 100644 (file)
index 0000000..a5bc297
--- /dev/null
@@ -0,0 +1,28 @@
+-----BEGIN PRIVATE KEY-----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+-----END PRIVATE KEY-----
index cc023667af1a5ddcc353600a736ed89ea1ef8a6d..5d5e1376ad5aa37631d1a8623befe07f3059fe80 100644 (file)
@@ -36,13 +36,17 @@ SERVERS := server-cn-and-alt-names \
 CLIENTS := client client-dn client-revoked client_ext
 
 #
-# To add a new non-standard key, add it to SPECIAL_KEYS and then add a recipe
-# for creating it to the "Special-case keys" section below.
+# To add a new non-standard certificate, add it to SPECIAL_CERTS and then add
+# a recipe for creating it to the "Special-case certificates" section below.
 #
+SPECIAL_CERTS := ssl/server-rsapss.crt
+
+# Likewise for non-standard keys
 SPECIAL_KEYS := ssl/server-password.key \
        ssl/client-der.key \
        ssl/client-encrypted-pem.key \
-       ssl/client-encrypted-der.key
+       ssl/client-encrypted-der.key \
+       ssl/server-rsapss.key
 
 #
 # These files are just concatenations of other files. You can add new ones to
@@ -65,7 +69,13 @@ CRLS := ssl/root.crl \
        ssl/client.crl \
        ssl/server.crl
 
-SSLFILES := $(STANDARD_CERTS) $(STANDARD_KEYS) $(SPECIAL_KEYS) $(COMBINATIONS) $(CRLS)
+SSLFILES := \
+       $(STANDARD_CERTS) \
+       $(STANDARD_KEYS) \
+       $(SPECIAL_CERTS) \
+       $(SPECIAL_KEYS) \
+       $(COMBINATIONS) \
+       $(CRLS)
 SSLDIRS := ssl/client-crldir \
        ssl/server-crldir \
        ssl/root+client-crldir \
@@ -85,6 +95,10 @@ sslfiles: $(SSLFILES) $(SSLDIRS)
 ssl/root_ca.crt: ssl/root_ca.key conf/root_ca.config
        openssl req -new -x509 -config conf/root_ca.config -days 10000 -key $< -out $@
 
+# Certificate using RSA-PSS algorithm. Also self-signed.
+ssl/server-rsapss.crt: ssl/server-rsapss.key conf/server-rsapss.config
+       $(OPENSSL) req -new -x509 -config conf/server-rsapss.config -key $< -out $@
+
 #
 # Special-case keys
 #
@@ -95,6 +109,10 @@ ssl/root_ca.crt: ssl/root_ca.key conf/root_ca.config
 ssl/server-password.key: ssl/server-cn-only.key
        openssl rsa -aes256 -in $< -out $@ -passout 'pass:secret1'
 
+# Key that uses the RSA-PSS algorithm
+ssl/server-rsapss.key:
+       $(OPENSSL) genpkey -algorithm rsa-pss -out $@
+
 # DER-encoded version of client.key
 ssl/client-der.key: ssl/client.key
        openssl rsa -in $< -outform DER -out $@
index 588f47a39b990dd271074c09eb6f54d53eecc060..566cb1256ba11ef00d274e0052a84e7a4133ec3c 100644 (file)
@@ -42,6 +42,10 @@ my $SERVERHOSTCIDR = '127.0.0.1/32';
 # Determine whether build supports tls-server-end-point.
 my $supports_tls_server_end_point =
   check_pg_config("#define HAVE_X509_GET_SIGNATURE_NID 1");
+# Determine whether build supports detection of hash algorithms for
+# RSA-PSS certificates.
+my $supports_rsapss_certs =
+  check_pg_config("#define HAVE_X509_GET_SIGNATURE_INFO 1");
 
 # Allocation of base connection string shared among multiple tests.
 my $common_connstr;
@@ -132,4 +136,17 @@ $node->connect_ok(
                qr/connection authenticated: identity="ssltestuser" method=scram-sha-256/
        ]);
 
+# Now test with a server certificate that uses the RSA-PSS algorithm.
+# This checks that the certificate can be loaded and that channel binding
+# works. (see bug #17760)
+if ($supports_rsapss_certs)
+{
+       switch_server_cert($node, certfile => 'server-rsapss');
+       $node->connect_ok(
+               "$common_connstr user=ssltestuser channel_binding=require",
+               "SCRAM with SSL and channel_binding=require, server certificate uses 'rsassaPss'",
+               log_like => [
+                       qr/connection authenticated: identity="ssltestuser" method=scram-sha-256/
+               ]);
+}
 done_testing();
index d30e8fcb117be3167d3ce55c85d2218b8d973cb3..790f03b05e654e97f5ea01baa4419eccc459dad8 100644 (file)
@@ -433,6 +433,7 @@ sub GenerateFiles
                HAVE_WCTYPE_H                            => 1,
                HAVE_WRITEV                              => undef,
                HAVE_X509_GET_SIGNATURE_NID              => 1,
+               HAVE_X509_GET_SIGNATURE_INFO             => undef,
                HAVE_X86_64_POPCNTQ                      => undef,
                HAVE__BOOL                               => undef,
                HAVE__BUILTIN_BSWAP16                    => undef,
@@ -553,7 +554,14 @@ sub GenerateFiles
 
                my ($digit1, $digit2, $digit3) = $self->GetOpenSSLVersion();
 
-               # More symbols are needed with OpenSSL 1.1.0 and above.
+               # Symbols needed with OpenSSL 1.1.1 and above.
+               if (   ($digit1 >= '3' && $digit2 >= '0' && $digit3 >= '0')
+                       || ($digit1 >= '1' && $digit2 >= '1' && $digit3 >= '1'))
+               {
+                       $define{HAVE_X509_GET_SIGNATURE_INFO} = 1;
+               }
+
+               # Symbols needed with OpenSSL 1.1.0 and above.
                if (   ($digit1 >= '3' && $digit2 >= '0' && $digit3 >= '0')
                        || ($digit1 >= '1' && $digit2 >= '1' && $digit3 >= '0'))
                {