From 589eb3898896c1ac916bc20069ecd5adb8534850 Mon Sep 17 00:00:00 2001 From: Clemens Lang Date: Fri, 17 Feb 2023 15:31:08 +0100 Subject: [PATCH] GCM: Implement explicit FIPS indicator for IV gen Implementation Guidance for FIPS 140-3 and the Cryptographic Module Verification Program, Section C.H requires guarantees about the uniqueness of key/iv pairs, and proposes a few approaches to ensure this. Provide an indicator for option 2 "The IV may be generated internally at its entirety randomly." Resolves: rhbz#2168289 Signed-off-by: Clemens Lang --- include/openssl/core_names.h | 1 + include/openssl/evp.h | 4 +++ .../implementations/ciphers/ciphercommon.c | 4 +++ .../ciphers/ciphercommon_gcm.c | 25 +++++++++++++++++++ 4 files changed, 34 insertions(+) Index: openssl-3.1.4/include/openssl/core_names.h =================================================================== --- openssl-3.1.4.orig/include/openssl/core_names.h +++ openssl-3.1.4/include/openssl/core_names.h @@ -99,6 +99,7 @@ extern "C" { #define OSSL_CIPHER_PARAM_CTS_MODE "cts_mode" /* utf8_string */ /* For passing the AlgorithmIdentifier parameter in DER form */ #define OSSL_CIPHER_PARAM_ALGORITHM_ID_PARAMS "alg_id_param" /* octet_string */ +#define OSSL_CIPHER_PARAM_SUSE_FIPS_INDICATOR "suse-fips-indicator" /* int */ #define OSSL_CIPHER_PARAM_TLS1_MULTIBLOCK_MAX_SEND_FRAGMENT \ "tls1multi_maxsndfrag" /* uint */ Index: openssl-3.1.4/include/openssl/evp.h =================================================================== --- openssl-3.1.4.orig/include/openssl/evp.h +++ openssl-3.1.4/include/openssl/evp.h @@ -750,6 +750,10 @@ void EVP_CIPHER_CTX_set_flags(EVP_CIPHER void EVP_CIPHER_CTX_clear_flags(EVP_CIPHER_CTX *ctx, int flags); int EVP_CIPHER_CTX_test_flags(const EVP_CIPHER_CTX *ctx, int flags); +# define EVP_CIPHER_SUSE_FIPS_INDICATOR_UNDETERMINED 0 +# define EVP_CIPHER_SUSE_FIPS_INDICATOR_APPROVED 1 +# define EVP_CIPHER_SUSE_FIPS_INDICATOR_NOT_APPROVED 2 + __owur int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, const unsigned char *key, const unsigned char *iv); /*__owur*/ int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, Index: openssl-3.1.4/providers/implementations/ciphers/ciphercommon.c =================================================================== --- openssl-3.1.4.orig/providers/implementations/ciphers/ciphercommon.c +++ openssl-3.1.4/providers/implementations/ciphers/ciphercommon.c @@ -149,6 +149,10 @@ static const OSSL_PARAM cipher_aead_know OSSL_PARAM_octet_string(OSSL_CIPHER_PARAM_AEAD_TAG, NULL, 0), OSSL_PARAM_size_t(OSSL_CIPHER_PARAM_AEAD_TLS1_AAD_PAD, NULL), OSSL_PARAM_octet_string(OSSL_CIPHER_PARAM_AEAD_TLS1_GET_IV_GEN, NULL, 0), + /* normally we would hide this under an #ifdef FIPS_MODULE, but that does + * not work in ciphercommon.c because it is compiled only once into + * libcommon.a */ + OSSL_PARAM_int(OSSL_CIPHER_PARAM_SUSE_FIPS_INDICATOR, NULL), OSSL_PARAM_END }; const OSSL_PARAM *ossl_cipher_aead_gettable_ctx_params( Index: openssl-3.1.4/providers/implementations/ciphers/ciphercommon_gcm.c =================================================================== --- openssl-3.1.4.orig/providers/implementations/ciphers/ciphercommon_gcm.c +++ openssl-3.1.4/providers/implementations/ciphers/ciphercommon_gcm.c @@ -224,6 +224,31 @@ int ossl_gcm_get_ctx_params(void *vctx, || !getivgen(ctx, p->data, p->data_size)) return 0; } + + /* We would usually hide this under #ifdef FIPS_MODULE, but + * ciphercommon_gcm.c is only compiled once into libcommon.a, so ifdefs do + * not work here. */ + p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_SUSE_FIPS_INDICATOR); + if (p != NULL) { + int fips_indicator = EVP_CIPHER_SUSE_FIPS_INDICATOR_APPROVED; + + /* Implementation Guidance for FIPS 140-3 and the Cryptographic Module + * Verification Program, Section C.H requires guarantees about the + * uniqueness of key/iv pairs, and proposes a few approaches to ensure + * this. This provides an indicator for option 2 "The IV may be + * generated internally at its entirety randomly." Note that one of the + * conditions of this option is that "The IV length shall be at least + * 96 bits (per SP 800-38D)." We do not specically check for this + * condition here, because gcm_iv_generate will fail in this case. */ + if (ctx->enc && !ctx->iv_gen_rand) + fips_indicator = EVP_CIPHER_SUSE_FIPS_INDICATOR_NOT_APPROVED; + + if (!OSSL_PARAM_set_int(p, fips_indicator)) { + ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); + return 0; + } + } + return 1; }