From ee6e381e4140efd5365ddf27a12055859103cf59 Mon Sep 17 00:00:00 2001
From: Clemens Lang <cllang@redhat.com>
Date: Fri, 17 Mar 2023 15:39:15 +0100
Subject: [PATCH] asymciphers, kem: Add explicit FIPS indicator

NIST SP 800-56Br2 section 6.4.2.1 requires either explicit key
confirmation (section 6.4.2.3.2), or assurance from a trusted third
party (section 6.4.2.3.1) for the KTS-OAEP key transport scheme and key
agreement schemes, but explicit key confirmation is not implemented and
cannot be implemented without protocol changes, and the FIPS provider
does not implement trusted third party validation, since it relies on
its callers to do that. A request for guidance sent to NIST did clarify
that OpenSSL can claim KTS-OAEP and RSASVE as approved, but we did add
an indicator to mark them as unapproved previously and should thus keep
the indicator available.

This does not affect RSA-OAEP decryption, because it is approved as
a component according to the FIPS 140-3 IG, section 2.4.G.

Resolves: rhbz#2179331
Resolves: RHEL-14083
Signed-off-by: Clemens Lang <cllang@redhat.com>
---
 include/openssl/evp.h                         |  4 +++
 .../implementations/asymciphers/rsa_enc.c     | 22 ++++++++++++++
 providers/implementations/kem/rsa_kem.c       | 30 ++++++++++++++++++-
 util/perl/OpenSSL/paramnames.pm               |  6 ++--
 4 files changed, 59 insertions(+), 3 deletions(-)

diff --git a/include/openssl/evp.h b/include/openssl/evp.h
index ec2ba46fbd..3803b03422 100644
--- a/include/openssl/evp.h
+++ b/include/openssl/evp.h
@@ -1764,6 +1764,10 @@ OSSL_DEPRECATEDIN_3_0 size_t EVP_PKEY_meth_get_count(void);
 OSSL_DEPRECATEDIN_3_0 const EVP_PKEY_METHOD *EVP_PKEY_meth_get0(size_t idx);
 # endif
 
+# define EVP_PKEY_REDHAT_FIPS_INDICATOR_UNDETERMINED 0
+# define EVP_PKEY_REDHAT_FIPS_INDICATOR_APPROVED     1
+# define EVP_PKEY_REDHAT_FIPS_INDICATOR_NOT_APPROVED 2
+
 EVP_KEYMGMT *EVP_KEYMGMT_fetch(OSSL_LIB_CTX *ctx, const char *algorithm,
                                const char *properties);
 int EVP_KEYMGMT_up_ref(EVP_KEYMGMT *keymgmt);
diff --git a/providers/implementations/asymciphers/rsa_enc.c b/providers/implementations/asymciphers/rsa_enc.c
index 568452ec56..2e7ea632d7 100644
--- a/providers/implementations/asymciphers/rsa_enc.c
+++ b/providers/implementations/asymciphers/rsa_enc.c
@@ -462,6 +462,27 @@ static int rsa_get_ctx_params(void *vprsactx, OSSL_PARAM *params)
     if (p != NULL && !OSSL_PARAM_set_uint(p, prsactx->implicit_rejection))
         return 0;
 
+#ifdef FIPS_MODULE
+    p = OSSL_PARAM_locate(params, OSSL_ASYM_CIPHER_PARAM_REDHAT_FIPS_INDICATOR);
+    if (p != NULL) {
+        int fips_indicator = EVP_PKEY_REDHAT_FIPS_INDICATOR_APPROVED;
+
+        /* NIST SP 800-56Br2 section 6.4.2.1 requires either explicit key
+         * confirmation (section 6.4.2.3.2), or assurance from a trusted third
+         * party (section 6.4.2.3.1) for the KTS-OAEP key transport scheme, but
+         * explicit key confirmation is not implemented here and cannot be
+         * implemented without protocol changes, and the FIPS provider does not
+         * implement trusted third party validation, since it relies on its
+         * callers to do that. We must thus mark RSA-OAEP as unapproved until
+         * we have received clarification from NIST on how library modules such
+         * as OpenSSL should implement TTP validation. */
+        fips_indicator = EVP_PKEY_REDHAT_FIPS_INDICATOR_NOT_APPROVED;
+
+        if (!OSSL_PARAM_set_int(p, fips_indicator))
+            return 0;
+    }
+#endif /* defined(FIPS_MODULE) */
+
     return 1;
 }
 
@@ -465,6 +483,7 @@ static const OSSL_PARAM known_gettable_ctx_params[] = {
     OSSL_PARAM_uint(OSSL_ASYM_CIPHER_PARAM_TLS_NEGOTIATED_VERSION, NULL),
 #ifdef FIPS_MODULE
     OSSL_PARAM_octet_string(OSSL_ASYM_CIPHER_PARAM_REDHAT_KAT_OEAP_SEED, NULL, 0),
+    OSSL_PARAM_int(OSSL_ASYM_CIPHER_PARAM_REDHAT_FIPS_INDICATOR, NULL),
 #endif /* FIPS_MODULE */
     OSSL_PARAM_uint(OSSL_ASYM_CIPHER_PARAM_IMPLICIT_REJECTION, NULL),
     OSSL_PARAM_END
diff --git a/providers/implementations/kem/rsa_kem.c b/providers/implementations/kem/rsa_kem.c
index 882cf16125..b4cc0f9237 100644
--- a/providers/implementations/kem/rsa_kem.c
+++ b/providers/implementations/kem/rsa_kem.c
@@ -151,11 +151,39 @@ static int rsakem_decapsulate_init(void *vprsactx, void *vrsa,
 static int rsakem_get_ctx_params(void *vprsactx, OSSL_PARAM *params)
 {
     PROV_RSA_CTX *ctx = (PROV_RSA_CTX *)vprsactx;
+#ifdef FIPS_MODULE
+    OSSL_PARAM *p;
+#endif /* defined(FIPS_MODULE) */
+
+    if (ctx == NULL)
+        return 0;
+
+#ifdef FIPS_MODULE
+    p = OSSL_PARAM_locate(params, OSSL_KEM_PARAM_REDHAT_FIPS_INDICATOR);
+    if (p != NULL) {
+        /* NIST SP 800-56Br2 section 6.4.2.1 requires either explicit key
+         * confirmation (section 6.4.2.3.2), or assurance from a trusted third
+         * party (section 6.4.2.3.1) for key agreement or key transport, but
+         * explicit key confirmation is not implemented here and cannot be
+         * implemented without protocol changes, and the FIPS provider does not
+         * implement trusted third party validation, since it relies on its
+         * callers to do that. We must thus mark RSASVE unapproved until we
+         * have received clarification from NIST on how library modules such as
+         * OpenSSL should implement TTP validation. */
+        int fips_indicator = EVP_PKEY_REDHAT_FIPS_INDICATOR_NOT_APPROVED;
+
+        if (!OSSL_PARAM_set_int(p, fips_indicator))
+            return 0;
+    }
+#endif /* defined(FIPS_MODULE) */
 
-    return ctx != NULL;
+    return 1;
 }
 
 static const OSSL_PARAM known_gettable_rsakem_ctx_params[] = {
+#ifdef FIPS_MODULE
+    OSSL_PARAM_int(OSSL_KEM_PARAM_REDHAT_FIPS_INDICATOR, NULL),
+#endif /* defined(FIPS_MODULE) */
     OSSL_PARAM_END
 };
 
diff --git a/util/perl/OpenSSL/paramnames.pm b/util/perl/OpenSSL/paramnames.pm
index 64e9809387..45ab0c8dc4 100644
--- a/util/perl/OpenSSL/paramnames.pm
+++ b/util/perl/OpenSSL/paramnames.pm
@@ -406,6 +406,7 @@ my %params = (
     'ASYM_CIPHER_PARAM_TLS_NEGOTIATED_VERSION' =>   "tls-negotiated-version",
     'ASYM_CIPHER_PARAM_IMPLICIT_REJECTION' =>       "implicit-rejection",
     'ASYM_CIPHER_PARAM_REDHAT_KAT_OEAP_SEED' =>     "redhat-kat-oaep-seed",
+    'ASYM_CIPHER_PARAM_REDHAT_FIPS_INDICATOR' =>    "redhat-fips-indicator",
 
 # Encoder / decoder parameters
 
@@ -438,8 +439,9 @@ my %params = (
     'SIGNATURE_PARAM_KAT' =>     "kat",
 
 # KEM parameters
-    'KEM_PARAM_OPERATION' =>            "operation",
-    'KEM_PARAM_IKME' =>                 "ikme",
+    'KEM_PARAM_OPERATION' =>             "operation",
+    'KEM_PARAM_REDHAT_FIPS_INDICATOR' => "redhat-fips-indicator",
+    'KEM_PARAM_IKME' =>                  "ikme",
 
 # Capabilities
 
-- 
2.39.2

