OSSL_PROVIDER-FIPS - OpenSSL FIPS provider
The OpenSSL FIPS provider is a special provider that conforms to
the Federal Information Processing Standards (FIPS) specified in FIPS 140-3.
This 'module' contains an approved set of cryptographic algorithms that is
validated by an accredited testing laboratory.
The implementations in this provider specifically have these
properties defined for approved algorithms:
- "provider=fips"
- "fips=yes"
It may be used in a property query string with fetching functions
such as EVP_MD_fetch(3) or EVP_CIPHER_fetch(3), as well as
with other functions that take a property query string, such as
EVP_PKEY_CTX_new_from_name(3).
To be FIPS compliant, it is mandatory to include
"fips=yes" as part of all property
queries. This ensures that only FIPS approved implementations are used for
cryptographic operations. The "fips=yes"
query may also include other non-crypto support operations that are not in
the FIPS provider, such as asymmetric key encoders, see "Asymmetric Key
Management" in OSSL_PROVIDER-default(7).
It is not mandatory to include
"provider=fips" as part of your property
query. Including "provider=fips" in your
property query guarantees that the OpenSSL FIPS provider is used for
cryptographic operations rather than other FIPS capable providers.
Algorithms that are fetched using "fips=yes" may still
be unapproved if certain conditions are not met. See "FIPS
indicators" in fips_module(7) for additional information.
See "Provider parameters" in provider-base(7) for
a list of base parameters. The OpenSSL FIPS provider also handles FIPS
indicator related parameters as specified by "FIPS indicator
options" in fips_config(5).
The OpenSSL FIPS provider supports these operations and
algorithms:
- HKDF, see
EVP_KDF-HKDF(7)
- TLS13-KDF, see
EVP_KDF-TLS13_KDF(7)
- SSKDF, see
EVP_KDF-SS(7)
- PBKDF2, see
EVP_KDF-PBKDF2(7)
- SSHKDF, see
EVP_KDF-SSHKDF(7)
- TLS1-PRF, see
EVP_KDF-TLS1_PRF(7)
- KBKDF, see
EVP_KDF-KB(7)
- X942KDF-ASN1, see
EVP_KDF-X942-ASN1(7)
- X942KDF-CONCAT, see
EVP_KDF-X942-CONCAT(7)
- X963KDF, see
EVP_KDF-X963(7)
- RSA, see
EVP_SIGNATURE-RSA(7)
- The X931 padding mode "OSSL_PKEY_RSA_PAD_MODE_X931" is no
longer supported for signature generation, but may be used for
verification for legacy use cases. (This is a FIPS 140-3 requirement)
- DSA, see
EVP_SIGNATURE-DSA(7)
- ED25519, see
EVP_SIGNATURE-ED25519(7)
- ED448, see
EVP_SIGNATURE-ED448(7)
- ECDSA, see
EVP_SIGNATURE-ECDSA(7)
- ML-DSA-44, see
EVP_SIGNATURE-ML-DSA(7)
- ML-DSA-65, see
EVP_SIGNATURE-ML-DSA(7)
- ML-DSA-87, see
EVP_SIGNATURE-ML-DSA(7)
- SLH-DSA, see
EVP_SIGNATURE-SLH-DSA(7)
- HMAC, see
EVP_SIGNATURE-HMAC(7)
- CMAC, see
EVP_SIGNATURE-CMAC(7)
- DH, see
EVP_KEYMGMT-DH(7)
- DHX, see
EVP_KEYMGMT-DHX(7)
- DSA, see
EVP_KEYMGMT-DSA(7)
- RSA, see
EVP_KEYMGMT-RSA(7)
- RSA-PSS
- EC, see
EVP_KEYMGMT-EC(7)
- ED25519, see
EVP_KEYMGMT-ED25519(7)
- ED448, see
EVP_KEYMGMT-ED448(7)
- X25519, see
EVP_KEYMGMT-X25519(7)
- This is an unapproved algorithm. The FIPS 140-3 IG states that
"Curves that are included in SP 800-186 but not included in SP
800-56Arev3 are not approved for key agreement".
- X448, see
EVP_KEYMGMT-X448(7)
- This is an unapproved algorithm. The FIPS 140-3 IG states that
"Curves that are included in SP 800-186 but not" included in SP
800-56Arev3 are not approved for key agreement".
- TLS1-PRF
- HKDF
- HMAC, see
EVP_KEYMGMT-HMAC(7)
- CMAC, see
EVP_KEYMGMT-CMAC(7)
- ML-DSA-44, see
EVP_KEYMGMT-ML-DSA(7)
- ML-DSA-65, see
EVP_KEYMGMT-ML-DSA(7)
- ML-DSA-87, see
EVP_KEYMGMT-ML-DSA(7)
- SLH-DSA-SHA2-128s, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHA2-128f, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHA2-192s, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHA2-192f, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHA2-256s, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHA2-256f, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHAKE-128s, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHAKE-128f, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHAKE-192s, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHAKE-192f, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHAKE-256s, see
EVP_KEYMGMT-SLH-DSA(7)
- SLH-DSA-SHAKE-256f, see
EVP_KEYMGMT-SLH-DSA(7)
A requirement of FIPS modules is to run cryptographic algorithm
self tests. FIPS 140-3 requires known answer tests to be run on startup as
well as conditional tests that run during cryptographic operations.
An optional callback mechanism is available to return information
to the user using OSSL_SELF_TEST_set_callback(3).
The parameters passed to the callback are described in
OSSL_SELF_TEST_new(3)
The OpenSSL FIPS module uses the following mechanism to provide
information about the self tests as they run. This is useful for debugging
if a self test is failing. The callback also allows forcing any self test to
fail, in order to check that it operates correctly on failure. Note that all
self tests run even if a self test failure occurs.
The FIPS module passes the following type(s) to
OSSL_SELF_TEST_onbegin().
- "Module_Integrity"
(OSSL_SELF_TEST_TYPE_MODULE_INTEGRITY)
- Uses HMAC SHA256 on the module file to validate that the module has not
been modified. The integrity value is compared to a value written to a
configuration file during installation.
- "KAT_Integrity" (OSSL_SELF_TEST_TYPE_KAT_INTEGRITY)
- Used during the Module Integrity test to perform a known answer test on
HMAC SHA256 prior to using it.
- "KAT_Cipher" (OSSL_SELF_TEST_TYPE_KAT_CIPHER)
- Known answer test for a symmetric cipher.
- "KAT_AsymmetricCipher"
(OSSL_SELF_TEST_TYPE_KAT_ASYM_CIPHER)
- Known answer test for a asymmetric cipher.
- "KAT_Digest" (OSSL_SELF_TEST_TYPE_KAT_DIGEST)
- Known answer test for a digest.
- "KAT_AsymmetricKeyGeneration"
(OSSL_SELF_TEST_TYPE_KAT_ASYM_KEYGEN)
- Known answer test for asymmetric key generation.
- "KAT_Signature" (OSSL_SELF_TEST_TYPE_KAT_SIGNATURE)
- Known answer test for a signature.
- "PCT_Signature" (OSSL_SELF_TEST_TYPE_PCT_SIGNATURE)
- Pairwise Consistency check for a signature.
- "KAT_KDF" (OSSL_SELF_TEST_TYPE_KAT_KDF)
- Known answer test for a key derivation function.
- "KAT_KA" (OSSL_SELF_TEST_TYPE_KAT_KA)
- Known answer test for key agreement.
- "KAT_KEM" (OSSL_SELF_TEST_TYPE_KAT_KEM)
- Known answer test for key encapsulation.
- "DRBG" (OSSL_SELF_TEST_TYPE_DRBG)
- Known answer test for a Deterministic Random Bit Generator.
- "Conditional_PCT" (OSSL_SELF_TEST_TYPE_PCT)
- Conditional test that is run during the generation of key pairs.
- "Import_PCT" (OSSL_SELF_TEST_TYPE_PCT_IMPORT)
- Conditional test that is run during the import of key pairs.
- "Conditional_KAT" (OSSL_SELF_TEST_TYPE_PCT_KAT)
- Conditional test run during generation that derive the public key from the
private key and checks that the public key matches. This is a SP 800-56A
requirement.
- "Continuous_RNG_Test" (OSSL_SELF_TEST_TYPE_CRNG)
- Continuous random number generator test.
- "Install_Integrity"
(OSSL_SELF_TEST_TYPE_INSTALL_INTEGRITY)
- This is deprecated. The option is no longer used since FIPS 140-3 requires
self tests to always run on startup. Previous FIPS 140-2 validations
allowed the self tests to be run just once.
The FIPS module passes the following descriptions(s) to
OSSL_SELF_TEST_onbegin().
- "HMAC" (OSSL_SELF_TEST_DESC_INTEGRITY_HMAC)
- "Module_Integrity" uses this.
- "RSA" (OSSL_SELF_TEST_DESC_PCT_RSA_PKCS1)
- "RSA" (OSSL_SELF_TEST_DESC_PCT_RSA)
- "ECDSA" (OSSL_SELF_TEST_DESC_PCT_ECDSA)
- "EDDSA" (OSSL_SELF_TEST_DESC_PCT_EDDSA)
- "DSA" (OSSL_SELF_TEST_DESC_PCT_DSA)
- "ML-DSA" (OSSL_SELF_TEST_DESC_PCT_ML_DSA)
- "ML-KEM" (OSSL_SELF_TEST_DESC_PCT_ML_KEM)
- "SLH-DSA" (OSSL_SELF_TEST_DESC_PCT_SLH_DSA)
- Key generation tests used with the "Pairwise_Consistency_Test"
type.
- "RSA_Encrypt" (OSSL_SELF_TEST_DESC_ASYM_RSA_ENC)
- "RSA_Decrypt" (OSSL_SELF_TEST_DESC_ASYM_RSA_DEC)
- "KAT_AsymmetricCipher" uses this to indicate an encrypt or
decrypt KAT.
- "ML-DSA" (OSSL_SELF_TEST_DESC_KEYGEN_ML_DSA)
- "ML-KEM" (OSSL_SELF_TEST_DESC_KEYGEN_ML_KEM)
- "SLH-DSA" (OSSL_SELF_TEST_DESC_KEYGEN_SLH_DSA)
- "KAT_AsymmetricKeyGeneration" uses this to indicate a key
generation KAT.
- "AES_GCM" (OSSL_SELF_TEST_DESC_CIPHER_AES_GCM)
- "AES_ECB_Decrypt"
(OSSL_SELF_TEST_DESC_CIPHER_AES_ECB)
- "TDES" (OSSL_SELF_TEST_DESC_CIPHER_TDES)
- Symmetric cipher tests used with the "KAT_Cipher" type.
- "SHA1" (OSSL_SELF_TEST_DESC_MD_SHA1)
- "SHA2" (OSSL_SELF_TEST_DESC_MD_SHA2)
- "SHA3" (OSSL_SELF_TEST_DESC_MD_SHA3)
- Digest tests used with the "KAT_Digest" type.
- "DSA" (OSSL_SELF_TEST_DESC_SIGN_DSA)
- "RSA" (OSSL_SELF_TEST_DESC_SIGN_RSA)
- "ECDSA" (OSSL_SELF_TEST_DESC_SIGN_ECDSA)
- "EDDSA" (OSSL_SELF_TEST_DESC_SIGN_EDDSA)
- "ML-DSA" (OSSL_SELF_TEST_DESC_SIGN_ML_DSA)
- "SLH-DSA" (OSSL_SELF_TEST_DESC_SIGN_SLH_DSA)
- Signature tests used with the "KAT_Signature" type.
- "ECDH" (OSSL_SELF_TEST_DESC_KA_ECDH)
- "DH" (OSSL_SELF_TEST_DESC_KA_DH)
- Key agreement tests used with the "KAT_KA" type.
- "HKDF" (OSSL_SELF_TEST_DESC_KDF_HKDF)
- "TLS13_KDF_EXTRACT"
(OSSL_SELF_TEST_DESC_KDF_TLS13_EXTRACT)
- "TLS13_KDF_EXPAND"
(OSSL_SELF_TEST_DESC_KDF_TLS13_EXPAND)
- "SSKDF" (OSSL_SELF_TEST_DESC_KDF_SSKDF)
- "X963KDF" (OSSL_SELF_TEST_DESC_KDF_X963KDF)
- "X942KDF" (OSSL_SELF_TEST_DESC_KDF_X942KDF)
- "PBKDF2" (OSSL_SELF_TEST_DESC_KDF_PBKDF2)
- "SSHKDF" (OSSL_SELF_TEST_DESC_KDF_SSHKDF)
- "TLS12_PRF" (OSSL_SELF_TEST_DESC_KDF_TLS12_PRF)
- "KBKDF" (OSSL_SELF_TEST_DESC_KDF_KBKDF)
- Key Encapsulation Function tests used with the "KAT_KEM"
type.
- "KEM_Encap" (OSSL_SELF_TEST_DESC_ENCAP_KEM)
- "KEM_Decap" (OSSL_SELF_TEST_DESC_DECAP_KEM)
- "KEM_Decap_Reject"
(OSSL_SELF_TEST_DESC_DECAP_REJ_KEM)
- Key Derivation Function tests used with the "KAT_KDF" type.
- "CTR" (OSSL_SELF_TEST_DESC_DRBG_CTR)
- "HASH" (OSSL_SELF_TEST_DESC_DRBG_HASH)
- "HMAC" (OSSL_SELF_TEST_DESC_DRBG_HMAC)
- DRBG tests used with the "DRBG" type.
- "RNG" (OSSL_SELF_TEST_DESC_RNG)
- "Continuous_RNG_Test" uses this.
A simple self test callback is shown below for illustrative
purposes.
#include <openssl/self_test.h>
static OSSL_CALLBACK self_test_cb;
static int self_test_cb(const OSSL_PARAM params[], void *arg)
{
int ret = 0;
const OSSL_PARAM *p = NULL;
const char *phase = NULL, *type = NULL, *desc = NULL;
p = OSSL_PARAM_locate_const(params, OSSL_PROV_PARAM_SELF_TEST_PHASE);
if (p == NULL || p->data_type != OSSL_PARAM_UTF8_STRING)
goto err;
phase = (const char *)p->data;
p = OSSL_PARAM_locate_const(params, OSSL_PROV_PARAM_SELF_TEST_DESC);
if (p == NULL || p->data_type != OSSL_PARAM_UTF8_STRING)
goto err;
desc = (const char *)p->data;
p = OSSL_PARAM_locate_const(params, OSSL_PROV_PARAM_SELF_TEST_TYPE);
if (p == NULL || p->data_type != OSSL_PARAM_UTF8_STRING)
goto err;
type = (const char *)p->data;
/* Do some logging */
if (strcmp(phase, OSSL_SELF_TEST_PHASE_START) == 0)
BIO_printf(bio_out, "%s : (%s) : ", desc, type);
if (strcmp(phase, OSSL_SELF_TEST_PHASE_PASS) == 0
|| strcmp(phase, OSSL_SELF_TEST_PHASE_FAIL) == 0)
BIO_printf(bio_out, "%s\n", phase);
/* Corrupt the SHA1 self test during the 'corrupt' phase by returning 0 */
if (strcmp(phase, OSSL_SELF_TEST_PHASE_CORRUPT) == 0
&& strcmp(desc, OSSL_SELF_TEST_DESC_MD_SHA1) == 0) {
BIO_printf(bio_out, "%s %s", phase, desc);
return 0;
}
ret = 1;
err:
return ret;
}
Some released versions of OpenSSL do not include a validated FIPS
provider. To determine which versions have undergone the validation process,
please refer to the OpenSSL Downloads page
<https://www.openssl.org/source/>. If you require FIPS-approved
functionality, it is essential to build your FIPS provider using one of the
validated versions listed there. Normally, it is possible to utilize a FIPS
provider constructed from one of the validated versions alongside
libcrypto and libssl compiled from any release within the same
major release series. This flexibility enables you to address bug fixes and
CVEs that fall outside the FIPS boundary.
You can load the FIPS provider into multiple library contexts as
any other provider. However the following restriction applies. The FIPS
provider cannot be used by multiple copies of OpenSSL libcrypto in a single
process.
As the provider saves core callbacks to the libcrypto obtained in
the OSSL_provider_init() call to global data it will fail if
subsequent invocations of its OSSL_provider_init() function yield
different addresses of these callbacks than in the initial call. This
happens when different copies of libcrypto are present in the memory of the
process and both try to load the same FIPS provider. A workaround is to have
a different copy of the FIPS provider loaded for each of the libcrypto
instances in the process.
This functionality was added in OpenSSL 3.0.
Copyright 2019-2025 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>.