man pages section 5: Standards, Environments, and Macros

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Updated: July 2014



openssl - OpenSSL cryptographic and Secure Sockets Layer toolkit


OpenSSL is a cryptography toolkit that implements the Secure Sockets Layer (SSLv2/v3) and Transport Layer Security (TLS v1) network protocols.

The following features are omitted from the binaries for issues including but not limited to patents, trademark, and US export restrictions: ECC, IDEA, MDC2, RC3, RC5, 4758_CCA Engine, AEP Engine, Atalla Engine, CHIL Engine, CSWIFT Engine, GMP Engine, NURON Engine, PadLock Engine, Sureware Engine, and UBSEC Engine.

The Dynamic Engine Support

The dynamic engine support has been enabled, which allows an external engine, in the form of a shared library, to be dynamically bound and used by an OpenSSL-based application.

Run the following command to see if the dynamic engine is supported:

$openssl engine dynamic
(dynamic) Dynamic engine loading support

The PKCS#11 Engine

The PKCS#11 engine has been included with the ENGINE name pkcs11. The engine was developed within Oracle and is not integrated in the OpenSSL project.

The PKCS#11 is a dynamic engine, and it is configured to use the Oracle Solaris Cryptographic Framework. See cryptoadm (1M) for configuration information.


The set of mechanisms available depends on installed Crypto Framework providers. To see what mechanisms can be offloaded to the Cryptographic Framework through the PKCS#11 engine on a given machine, run the following command:

$ /usr/sfw/bin/openssl engine dynamic -pre
SO_PATH:/lib/openssl/engines/64/ -pre LOAD -t -c

In order to verify the use of the PKCS#11 engine and the use of hardware acceleration with the OpenSSL application, you must specify the EVP option. EVP stands for "EnVeloPE" API, which is the API applications such as Apache use to access OpenSSL cryptography. Use the EVP option to get the most accurate "openssl speed" results.

$ /usr/bin/openssl speed -evp aes-128-cbc -engine pkcs11

Due to requirements of the PKCS#11 standard regarding fork(2) behavior, some applications that use the OpenSSL EVP interfaces and fork() with active crypto contexts might experience unexpected behavior.

Using FIPS Mode

FIPS-140 capable OpenSSL is available in Oracle Solaris.

The IPS package mediator feature is used to activate the non-FIPS-140 version or the FIPS-140 version of OpenSSL.

By default, the non-FIPS-140 version (default implementation) is activated. Use the pkg set-mediator command to switch to the FIPS-140 version of OpenSSL. Before switching to the fips-140 implementation, ensure that the fips-140 implementation exists in the list shown by the pkg mediator -a openssl command. Otherwise, the system might become unusable.

# pkg set-mediator -I fips-140 openssl

To switch back to the default non-FIPS-140 version, use the following command:

# pkg set-mediator -I default openssl

It is recommended to perform the mediator implementation change in an alternate BE.

For more information, see Managing Encryption and Certificates in Oracle Solaris 11.2 .

When the FIPS-140 version of OpenSSL is activated, an application can run in FIPS-140 mode or non-FIPS-140 mode. An application must explicitly call FIPS_mode_set() in order to activate FIPS-140 mode.

Building an OpenSSL Application

To build an OpenSSL application, use the following cc command line options:

cc [ flag... ] file... -lcrypto -lssl [ library... ]

Accessing RSA Keys in PKCS#11 Keystores

OpenSSL can access RSA keys in PKCS#11 keystores using the following functions of the ENGINE API:

EVP_PKEY *ENGINE_load_private_key(ENGINE *e,
 const char *key_id, UI_METHOD *ui_method,
 void *callback_data)

EVP_PKEY *ENGINE_load_public_key(ENGINE *e,
 const char *key_id, UI_METHOD *ui_method,
 void *callback_data)

key_id, formerly for filenames only, can be now also set to a PKCS#11 URI. The EVP_PKEY structure is newly allocated and caller is responsible to free the structure later. To avoid clashes with existing filenames, file:// prefix for filenames is now also accepted but only when the PKCS#11 engine is in use. The PKCS#11 URI specification follows:


The ordering of keywords is not significant. The PKCS#11 engine uses the keystore for the slot chosen for public key operations, which is metaslot on a standard configured machine. Currently, the PKCS#11 engine ignores the objecttype keyword. The only mandatory keyword is object which is the key object label. For information on how to use a different, possibly hardware, keystore with metaslot, see libpkcs11 (3LIB) .

The token PIN is provided by way of the passphrasedialog keyword and is either read from the terminal (builtin) or from the output of an external command (exec:<file>). The PIN is used to log into the token and by default is deleted from the memory then. The keyword pin is intentionally not provided due to inherent security problems of possible use of a password in the process arguments.

Due to fork safety issues the application must re-login if the child continues to use the PKCS#11 engine. It is done inside of the engine automatically if fork is detected and in that case, exec:<file> option of the passphrasedialog keyword can be used. Alternatively, an environment variable OPENSSL_PKCS11_PIN_CACHING_POLICY can be used to allow the PIN to be cached in memory and reused in the child. It can be set to none which is the default, memory to store the PIN in memory, and mlocked-memory to keep the PIN in a locked page using mlock(3C). PRIV_PROC_LOCK_MEMORY privilege is required in that case.

Sensitive parts of private keys are never read from the token to the process memory no matter whether the key is tagged with sensitive flag or not. The PKCS#11 engine uses the public components as a search key to get a PKCS#11 object handle to the private key.

To use the RSA keys by reference, high level API functions such as RSA_public_decrypt(), EVP_PKEY_set1_RSA(), or EVP_SignInit() must be used. Low level functions might go around the engine and fail to make use of the feature.

OpenSSL Thread and Fork Safety

OpenSSL provides an interface CRYPTO_set_locking_callback() for any consumers to set its own locking callback function. However, setting of the callback function by a library can lead to segmentation fault, if the library is unloaded while other parts of the stack are still using OpenSSL.

In order to prevent this issue, OpenSSL on Solaris sets up the mutexes and the locking callback function internally within OpenSSL. An application or library might still call CRYPTO_set_locking_callback(), but setting of their own callback function will be ignored.

Additional Documentation

Extensive additional documentation for OpenSSL modules is available in the /usr/share/man/man1openssl, /usr/share/man/man3openssl, /usr/share/man/man5openssl, and /usr/share/man/man7openssl directories.

To view the license terms, attribution, and copyright for OpenSSL, run pkg info --license library/security/openssl.


Example 1 Generating and Printing a Public Key

The following example generates and prints a public key stored in an already initialized PKCS#11 keystore. Notice the use of -engine pkcs11 and -inform e.

$ pktool gencert keystore=pkcs11 label=mykey \
   subject="CN=test" keytype=rsa keylen=1024 serial=01
$ openssl rsa -in "pkcs11:object=mykey;passphrasedialog=builtin"\
   -pubout -text -engine pkcs11 -inform e


See attributes(5) for a description of the following attributes:

library/security/openssl, library/security/openssl
Interface Stability

See also

crle(1), cryptoadm(1M), libpkcs11(3LIB), attributes(5), privileges(5)

/usr/share/man/man1openssl/openssl.1openssl, /usr/share/man/man1openssl/CRYPTO_num_locks.3openssl, /usr/share/man/man3openssl/engine.3, /usr/share/man/man3openssl/evp.3