From e3d6fca1af033d00c47bcd8f9ba28fcf1aa476aa Mon Sep 17 00:00:00 2001
From: Clemens Lang <cllang@redhat.com>
Date: Tue, 7 Jun 2022 12:02:49 +0200
Subject: [PATCH] fips: Expose a FIPS indicator
FIPS 140-3 requires us to indicate whether an operation was using
approved services or not. The FIPS 140-3 implementation guidelines
provide two basic approaches to doing this: implicit indicators, and
explicit indicators.
Implicit indicators are basically the concept of "if the operation
passes, it was approved". We were originally aiming for implicit
indicators in our copy of OpenSSL. However, this proved to be a problem,
because we wanted to certify a signature service, and FIPS 140-3
requires that a signature service computes the digest to be signed
within the boundaries of the FIPS module. Since we were planning to
certify fips.so only, this means that EVP_PKEY_sign/EVP_PKEY_verify
would have to be blocked. Unfortunately, EVP_SignFinal uses
EVP_PKEY_sign internally, but outside of fips.so and thus outside of the
FIPS module boundary. This means that using implicit indicators in
combination with certifying only fips.so would require us to block both
EVP_PKEY_sign and EVP_SignFinal, which are the two APIs currently used
by most users of OpenSSL for signatures.
EVP_DigestSign would be acceptable, but has only been added in 3.0 and
is thus not yet widely used.
As a consequence, we've decided to introduce explicit indicators so that
EVP_PKEY_sign and EVP_SignFinal can continue to work for now, but
FIPS-aware applications can query the explicit indicator to check
whether the operation was approved.
To avoid affecting the ABI and public API too much, this is implemented
as an exported symbol in fips.so and a private header, so applications
that wish to use this will have to dlopen(3) fips.so, locate the
function using dlsym(3), and then call it. These applications will have
to build against the private header in order to use the returned
pointer.
Modify util/mkdef.pl to support exposing a symbol only for a specific
provider identified by its name and path.
Signed-off-by: Clemens Lang <cllang@redhat.com>
---
doc/build.info | 6 ++
doc/man7/fips_module_indicators.pod | 154 ++++++++++++++++++++++++++++
providers/fips/fipsprov.c | 71 +++++++++++++
providers/fips/indicator.h | 66 ++++++++++++
util/mkdef.pl | 25 ++++-
util/providers.num | 1 +
6 files changed, 322 insertions(+), 1 deletion(-)
create mode 100644 doc/man7/fips_module_indicators.pod
create mode 100644 providers/fips/indicator.h
diff --git a/doc/build.info b/doc/build.info
index b0aa4297a4..af235113bb 100644
--- a/doc/build.info
+++ b/doc/build.info
@@ -4389,6 +4389,10 @@ DEPEND[html/man7/fips_module.html]=man7/fips_module.pod
GENERATE[html/man7/fips_module.html]=man7/fips_module.pod
DEPEND[man/man7/fips_module.7]=man7/fips_module.pod
GENERATE[man/man7/fips_module.7]=man7/fips_module.pod
+DEPEND[html/man7/fips_module_indicators.html]=man7/fips_module_indicators.pod
+GENERATE[html/man7/fips_module_indicators.html]=man7/fips_module_indicators.pod
+DEPEND[man/man7/fips_module_indicators.7]=man7/fips_module_indicators.pod
+GENERATE[man/man7/fips_module_indicators.7]=man7/fips_module_indicators.pod
DEPEND[html/man7/life_cycle-cipher.html]=man7/life_cycle-cipher.pod
GENERATE[html/man7/life_cycle-cipher.html]=man7/life_cycle-cipher.pod
DEPEND[man/man7/life_cycle-cipher.7]=man7/life_cycle-cipher.pod
@@ -4631,6 +4635,7 @@ html/man7/ct.html \
html/man7/des_modes.html \
html/man7/evp.html \
html/man7/fips_module.html \
+html/man7/fips_module_indicators.html \
html/man7/life_cycle-cipher.html \
html/man7/life_cycle-digest.html \
html/man7/life_cycle-kdf.html \
@@ -4754,6 +4759,7 @@ man/man7/ct.7 \
man/man7/des_modes.7 \
man/man7/evp.7 \
man/man7/fips_module.7 \
+man/man7/fips_module_indicators.7 \
man/man7/life_cycle-cipher.7 \
man/man7/life_cycle-digest.7 \
man/man7/life_cycle-kdf.7 \
diff --git a/doc/man7/fips_module_indicators.pod b/doc/man7/fips_module_indicators.pod
new file mode 100644
index 0000000000..23db2b395c
--- /dev/null
+++ b/doc/man7/fips_module_indicators.pod
@@ -0,0 +1,154 @@
+=pod
+
+=head1 NAME
+
+fips_module_indicators - Red Hat OpenSSL FIPS module indicators guide
+
+=head1 DESCRIPTION
+
+This guide documents how the Red Hat Enterprise Linux 9 OpenSSL FIPS provider
+implements Approved Security Service Indicators according to the FIPS 140-3
+Implementation Guidelines, section 2.4.C. See
+L<https://csrc.nist.gov/CSRC/media/Projects/cryptographic-module-validation-program/documents/fips%20140-3/FIPS%20140-3%20IG.pdf>
+for the FIPS 140-3 Implementation Guidelines.
+
+For all approved services except signatures, the Red Hat OpenSSL FIPS provider
+uses the return code as the indicator as understood by FIPS 140-3. That means
+that every operation that succeeds denotes use of an approved security service.
+Operations that do not succeed may not have been approved security services, or
+may have been used incorrectly.
+
+For signatures, an explicit indicator API is available to determine whether
+a selected operation is an approved security service, in combination with the
+return code of the operation. For a signature operation to be approved, the
+explicit indicator must claim it as approved, and it must succeed.
+
+=head2 Querying the explicit indicator
+
+The Red Hat OpenSSL FIPS provider exports a symbol named
+I<redhat_ossl_query_fipsindicator> that provides information on which signature
+operations are approved security functions. To use this function, either link
+against I<fips.so> directly, or load it at runtime using dlopen(3) and
+dlsym(3).
+
+ #include <openssl/core_dispatch.h>
+ #include "providers/fips/indicator.h"
+
+ void *provider = dlopen("/usr/lib64/ossl-modules/fips.so", RTLD_LAZY);
+ if (provider == NULL) {
+ fprintf(stderr, "%s\n", dlerror());
+ // handle error
+ }
+
+ const OSSL_RH_FIPSINDICATOR_ALORITHM *(*redhat_ossl_query_fipsindicator)(int) \
+ = dlsym(provider, "redhat_ossl_query_fipsindicator");
+ if (redhat_ossl_query_fipsindicator == NULL) {
+ fprintf(stderr, "%s\n", dlerror());
+ fprintf(stderr, "Does your copy of fips.so have the required Red Hat"
+ " patches?\n");
+ // handle error
+ }
+
+Note that this uses the I<providers/fips/indicator.h> header, which is not
+public. Install the I<openssl-debugsource> package from the I<BaseOS-debuginfo>
+repository using I<dnf debuginfo-install openssl> and include
+I</usr/src/debug/openssl-3.*/> in the compiler's include path.
+
+I<redhat_ossl_query_fipsindicator> expects an operation ID as its only
+argument. Currently, the only supported operation ID is I<OSSL_OP_SIGNATURE> to
+obtain the indicators for signature operations. On success, the return value is
+a pointer to an array of I<OSSL_RH_FIPSINDICATOR_STRUCT>s. On failure, NULL is
+returned. The last entry in the array is indicated by I<algorithm_names> being
+NULL.
+
+ typedef struct ossl_rh_fipsindicator_algorithm_st {
+ const char *algorithm_names; /* key */
+ const char *property_definition; /* key */
+ const OSSL_RH_FIPSINDICATOR_DISPATCH *indicators;
+ } OSSL_RH_FIPSINDICATOR_ALGORITHM;
+
+ typedef struct ossl_rh_fipsindicator_dispatch_st {
+ int function_id;
+ int approved;
+ } OSSL_RH_FIPSINDICATOR_DISPATCH;
+
+The I<algorithm_names> field is a colon-separated list of algorithm names from
+one of the I<PROV_NAMES_...> constants, e.g., I<PROV_NAMES_RSA>. strtok(3) can
+be used to locate the appropriate entry. See the example below, where
+I<algorithm> contains the algorithm name to search for:
+
+ const OSSL_RH_FIPSINDICATOR_DISPATCH *indicator_dispatch = NULL;
+ const OSSL_RH_FIPSINDICATOR_ALGORITHM *indicator =
+ redhat_ossl_query_fipsindicator(operation_id);
+ if (indicator == NULL) {
+ fprintf(stderr, "No indicator for operation, probably using implicit"
+ " indicators.\n");
+ // handle error
+ }
+
+ for (; indicator->algorithm_names != NULL; ++indicator) {
+ char *algorithm_names = strdup(indicator->algorithm_names);
+ if (algorithm_names == NULL) {
+ perror("strdup(3)");
+ // handle error
+ }
+
+ const char *algorithm_name = strtok(algorithm_names, ":");
+ for (; algorithm_name != NULL; algorithm_name = strtok(NULL, ":")) {
+ if (strcasecmp(algorithm_name, algorithm) == 0) {
+ indicator_dispatch = indicator->indicators;
+ free(algorithm_names);
+ algorithm_names = NULL;
+ break;
+ }
+ }
+ free(algorithm_names);
+ }
+ if (indicator_dispatch == NULL) {
+ fprintf(stderr, "No indicator for algorithm %s.\n", algorithm);
+ // handle error
+ }
+
+If an appropriate I<OSSL_RH_FIPSINDICATOR_DISPATCH> array is available for the
+given algorithm name, it maps function IDs to their approval status. The last
+entry is indicated by a zero I<function_id>. I<approved> is
+I<OSSL_RH_FIPSINDICATOR_APPROVED> if the operation is an approved security
+service, or part of an approved security service, or
+I<OSSL_RH_FIPSINDICATOR_UNAPPROVED> otherwise. Any other value is invalid.
+Function IDs are I<OSSL_FUNC_*> constants from I<openssl/core_dispatch.h>,
+e.g., I<OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE> or I<OSSL_FUNC_SIGNATURE_SIGN>.
+
+Assuming I<function_id> is the function in question, the following code can be
+used to query the approval status:
+
+ for (; indicator_dispatch->function_id != 0; ++indicator_dispatch) {
+ if (indicator_dispatch->function_id == function_id) {
+ switch (indicator_dispatch->approved) {
+ case OSSL_RH_FIPSINDICATOR_APPROVED:
+ // approved security service
+ break;
+ case OSSL_RH_FIPSINDICATOR_UNAPPROVED:
+ // unapproved security service
+ break;
+ default:
+ // invalid result
+ break;
+ }
+ break;
+ }
+ }
+
+=head1 SEE ALSO
+
+L<fips_module(7)>, L<provider(7)>
+
+=head1 COPYRIGHT
+
+Copyright 2022 Red Hat, Inc. All Rights Reserved.
+
+Licensed under the Apache License 2.0 (the "License"). You may not use
+this file except in compliance with the License. You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+=cut
diff --git a/providers/fips/fipsprov.c b/providers/fips/fipsprov.c
index de391ce067..1cfd71c5cf 100644
--- a/providers/fips/fipsprov.c
+++ b/providers/fips/fipsprov.c
@@ -23,6 +23,7 @@
#include "prov/seeding.h"
#include "self_test.h"
#include "internal/core.h"
+#include "indicator.h"
static const char FIPS_DEFAULT_PROPERTIES[] = "provider=fips,fips=yes";
static const char FIPS_UNAPPROVED_PROPERTIES[] = "provider=fips,fips=no";
@@ -425,6 +426,68 @@ static const OSSL_ALGORITHM fips_signature[] = {
{ NULL, NULL, NULL }
};
+static const OSSL_RH_FIPSINDICATOR_DISPATCH redhat_rsa_signature_indicators[] = {
+ { OSSL_FUNC_SIGNATURE_NEWCTX, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SIGN_INIT, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_SIGN, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_VERIFY_INIT, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_VERIFY, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_VERIFY_RECOVER_INIT, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_VERIFY_RECOVER, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_FREECTX, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DUPCTX, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { 0, OSSL_RH_FIPSINDICATOR_UNAPPROVED }
+};
+
+static const OSSL_RH_FIPSINDICATOR_DISPATCH redhat_ecdsa_signature_indicators[] = {
+ { OSSL_FUNC_SIGNATURE_NEWCTX, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SIGN_INIT, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_SIGN, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_VERIFY_INIT, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_VERIFY, OSSL_RH_FIPSINDICATOR_UNAPPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_FREECTX, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_DUPCTX, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS, OSSL_RH_FIPSINDICATOR_APPROVED },
+ { 0, OSSL_RH_FIPSINDICATOR_UNAPPROVED }
+};
+
+static const OSSL_RH_FIPSINDICATOR_ALGORITHM redhat_indicator_fips_signature[] = {
+ { PROV_NAMES_RSA, FIPS_DEFAULT_PROPERTIES,
+ redhat_rsa_signature_indicators },
+#ifndef OPENSSL_NO_EC
+ { PROV_NAMES_ECDSA, FIPS_DEFAULT_PROPERTIES,
+ redhat_ecdsa_signature_indicators },
+#endif
+ { NULL, NULL, NULL }
+};
+
static const OSSL_ALGORITHM fips_asym_cipher[] = {
{ PROV_NAMES_RSA, FIPS_DEFAULT_PROPERTIES, ossl_rsa_asym_cipher_functions },
{ NULL, NULL, NULL }
@@ -527,6 +590,14 @@ static void fips_deinit_casecmp(void) {
freelocale(loc);
}
+const OSSL_RH_FIPSINDICATOR_ALGORITHM *redhat_ossl_query_fipsindicator(int operation_id) {
+ switch (operation_id) {
+ case OSSL_OP_SIGNATURE:
+ return redhat_indicator_fips_signature;
+ }
+ return NULL;
+}
+
static void fips_teardown(void *provctx)
{
OSSL_LIB_CTX_free(PROV_LIBCTX_OF(provctx));
diff --git a/providers/fips/indicator.h b/providers/fips/indicator.h
new file mode 100644
index 0000000000..b323efe44c
--- /dev/null
+++ b/providers/fips/indicator.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#ifndef OPENSSL_FIPS_INDICATOR_H
+# define OPENSSL_FIPS_INDICATOR_H
+# pragma once
+
+# ifdef __cplusplus
+extern "C" {
+# endif
+
+# define OSSL_RH_FIPSINDICATOR_UNAPPROVED (0)
+# define OSSL_RH_FIPSINDICATOR_APPROVED (1)
+
+/*
+ * FIPS indicator dispatch table element. function_id numbers and the
+ * functions are defined in core_dispatch.h, see macros with
+ * 'OSSL_CORE_MAKE_FUNC' in their names.
+ *
+ * An array of these is always terminated by function_id == 0
+ */
+typedef struct ossl_rh_fipsindicator_dispatch_st {
+ int function_id;
+ int approved;
+} OSSL_RH_FIPSINDICATOR_DISPATCH;
+
+/*
+ * Type to tie together algorithm names, property definition string and the
+ * algorithm implementation's FIPS indicator status in the form of a FIPS
+ * indicator dispatch table.
+ *
+ * An array of these is always terminated by algorithm_names == NULL
+ */
+typedef struct ossl_rh_fipsindicator_algorithm_st {
+ const char *algorithm_names; /* key */
+ const char *property_definition; /* key */
+ const OSSL_RH_FIPSINDICATOR_DISPATCH *indicators;
+} OSSL_RH_FIPSINDICATOR_ALGORITHM;
+
+/**
+ * Query FIPS indicator status for the given operation. Possible values for
+ * 'operation_id' are currently only OSSL_OP_SIGNATURE, as all other algorithms
+ * use implicit indicators. The return value is an array of
+ * OSSL_RH_FIPSINDICATOR_ALGORITHMs, terminated by an entry with
+ * algorithm_names == NULL. 'algorithm_names' is a colon-separated list of
+ * algorithm names, 'property_definition' a comma-separated list of properties,
+ * and 'indicators' is a list of OSSL_RH_FIPSINDICATOR_DISPATCH structs. This
+ * list is terminated by function_id == 0. 'function_id' is one of the
+ * OSSL_FUNC_* constants, e.g., OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL.
+ *
+ * If there is no entry in the returned struct for the given operation_id,
+ * algorithm name, or function_id, the algorithm is unapproved.
+ */
+const OSSL_RH_FIPSINDICATOR_ALGORITHM *redhat_ossl_query_fipsindicator(int operation_id);
+
+# ifdef __cplusplus
+}
+# endif
+
+#endif
diff --git a/util/mkdef.pl b/util/mkdef.pl
index a1c76f7c97..eda39b71ee 100755
--- a/util/mkdef.pl
+++ b/util/mkdef.pl
@@ -149,7 +149,8 @@ $ordinal_opts{filter} =
return
$item->exists()
&& platform_filter($item)
- && feature_filter($item);
+ && feature_filter($item)
+ && fips_filter($item, $name);
};
my $ordinals = OpenSSL::Ordinals->new(from => $ordinals_file);
@@ -205,6 +206,28 @@ sub feature_filter {
return $verdict;
}
+sub fips_filter {
+ my $item = shift;
+ my $name = uc(shift);
+ my @features = ( $item->features() );
+
+ # True if no features are defined
+ return 1 if scalar @features == 0;
+
+ my @matches = grep(/^ONLY_.*$/, @features);
+ if (@matches) {
+ # There is at least one only_* flag on this symbol, check if any of
+ # them match the name
+ for (@matches) {
+ if ($_ eq "ONLY_${name}") {
+ return 1;
+ }
+ }
+ return 0;
+ }
+ return 1;
+}
+
sub sorter_unix {
my $by_name = OpenSSL::Ordinals::by_name();
my %weight = (
diff --git a/util/providers.num b/util/providers.num
index 4e2fa81b98..77879d0e5f 100644
--- a/util/providers.num
+++ b/util/providers.num
@@ -1 +1,2 @@
OSSL_provider_init 1 * EXIST::FUNCTION:
+redhat_ossl_query_fipsindicator 1 * EXIST::FUNCTION:ONLY_PROVIDERS/FIPS
--
2.35.3