Specify 'OFF' or '0' if SAF key ring certificates are only validated to the trust anchor certificate. If a sole intermediate certificate is found in a SAF key ring and the next issuer is not found in the same SAF key ring, the intermediate certificate acts as a trust anchor and the certificate chain is considered complete. By default, SAF key ring certificates are only validated to the trust anchor certificate. This setting does not affect the validation of SSL key database file and PKCS #11 token certificates because these certificates are always validated to the root CA certificate. The default value is 'OFF'.

A value of '2459' specifies certificate validation against RFC 2459 only. A value of '3280' specifies certificate validation against RFC 3280 only. A value of '5280' specifies certificate validation against RFC 5280 only. A value of 'ANY' specifies certificate validation against RFC 2459 initially - if that fails, validate against RFC 3280 - if that fails, validate against RFC 5280. The default value is 'ANY'.

Specifies the list of elliptic curves that are supported by the client as a string consisting of 1 or more 4-character values in order of preference for use. The list is used by the client to guide the server as to which elliptic curves are preferred when using ECC-based cipher suites for TLS V1.0 and higher protocols.

Only NIST recommended curves can be specified. To use Brainpool standard curves for an SSL environment or connection, set GSK_CLIENT_ECURVE_LIST to "" or use gsk_attribute_set_buffer() to re-initialize the GSK_CLIENT_ECURVE_LIST buffer to NULL.

See Table 5 for a list of valid 4-character elliptic curve specifications.

Specifies the number of hours that a cached CRL remains valid.

The valid timeout values are 0 through 720 and defaults to 24. A value of 0 disables the CRL cache.

Specifies the level of security SSL applications use when contacting LDAP servers to check CRLs for revoked certificates during certificate validation.

CRLs located are cached according to the GSK_CRL_CACHE_TIMEOUT setting of the SSL environment. To enforce contact with the LDAP server for each CRL check, CRL caching must be disabled. If a CRL is not defined, an empty CRL is placed in the CRL cache to prevent repeated calls to the LDAP server. This entry is not cleared until the CRL cache timeout is reached. See gsk_attribute_set_numeric_value() and Environment variables for more information about the GSK_CRL_CACHE_TIMEOUT setting.

LOW - Certificate validation does not fail if the LDAP server cannot be contacted.

MEDIUM - Certificate validation requires the LDAP server to be contactable, but does not require a CRL to be defined. This is the default.

HIGH - Certificate validation requires the LDAP server to be contactable and a CRL to be defined.

Specifies whether the SSL condition handler should call the cdump() service to dump the current thread before resuming the failing routine. The dump is placed in the current directory unless LE is instructed to use a different directory by the _CEE_DMPTARG environment variable. See z/OS Language Environment Programming Guide for more information about LE callable services.

A value of '1' enables SSL dumps and a value of '0' disables SSL dumps. The default is '0'. The export file contains just the requested certificate when the DER format is selected.

GSK_EXTENDED_RENEGOTIATION_
INDICATOR

A value of “OPTIONAL” does not require the renegotiation indicator during initial handshake. This is the default.

A value of “CLIENT” allows the client initial handshake to proceed only if the server indicates support for RFC 5746 Renegotiation.

A value of “SERVER” allows the server initial handshake to proceed only if the client indicates support for RFC 5746 Renegotiation.

A value of “BOTH” will allow the server and client initial handshakes to proceed only if partner indicates support for RFC 5746 Renegotiation.

Specifies whether the hardware cryptographic support is used. Note that ICSF (Integrated Cryptographic Service Facility) must be configured and running in order for System SSL to use the hardware cryptographic support that is available in the cryptographic cards.

SHA-1, SHA-2, DES, Triple DES, and AES hardware functions can be used without ICSF if the zArchitecture message-security assist is installed.

For more information about hardware cryptographic support, see Using cryptographic features with System SSL.

Selected hardware cryptographic functions can be disabled by setting the appropriate bits to zero in the GSK_HW_CRYPTO value. The corresponding software algorithms are used when a hardware function is disabled. These bit assignments are defined:

• 1 = SHA-1 digest generation
• 2 = 56-bit DES encryption/decryption
• 4 = 168-bit Triple DES encryption/decryption
• 8 = Public key encryption/decryption
• 16 = AES 128-bit encryption/decryption
• 32 = SHA-256 digest generation
• 64 = AES-256-bit encryption/decryption
• 128 = SHA-224 digest generation
• 256 = SHA-384 digest generation
• 512 = SHA-512 digest generation

A value of '0' disables the use of hardware support while a value of '65535' enables the use of hardware support. The default value is '65535' and only available hardware support is used.

Specifies the label of the key that is used to authenticate the application.

Any key label. The default key is used if a key label is not specified.

Specifies the name of the key database file, SAF key ring, or z/OS® PKCS #11 token. A key database is used if the GSK_KEYRING_PW or GSK_KEYRING_STASH environment variable is also specified. Otherwise, a SAF key ring or z/OS PKCS #11 token is used.

Note that certificate private keys are not available when using a SAF key ring owned by another user.

The user must have READ access to resource USER.tokenname in the CRYPTOZ class.

The SAF key ring name is specified as "userid/keyring". The current user ID is used if the user ID is omitted.

The z/OS PKCS #11 token name is specified as "*TOKEN*/token-name".

If no certificate source is specified, defaults to NULL.

Specifies the password for the key database.

NULL or value consisting of up to 128 characters.

The default value is NULL

Specifies the name of the key database password stash file.

The stash file name always has an extension of ".sth" and the supplied name is changed if it does not have the correct extension. The GSK_KEYRING_PW environment variable is used instead of the GSK_KEYRING_STASH environment variable if it is also specified.

The default value is NULL.

Specifies the password to use when connecting to the LDAP server.

The default value is NULL.

Specifies the LDAP server port.

Port must be between 1 and 65535. Port 389 is used if no LDAP server port is specified.

Specifies one or more blank-separated LDAP server host names. The LDAP server is used to obtain CA certificates when validating a certificate and the local database does not contain the required certificate. The local database must contain the required certificates if no LDAP server is specified. Even when an LDAP server is used, root CA certificates must be found in the local database since the LDAP server is not a trusted data source. The LDAP server is also used to obtain certificate revocation lists.

Each host name can contain an optional port number that is separated from the host name by a colon.

The default value is NULL.

Specifies the distinguished name to use when connecting to the LDAP server.

The default value is NULL.

Specifies whether the SSL V2 protocol is supported. The SSL V2 protocol should be disabled whenever possible since the SSL V3 protocol provides significant security enhancements. This variable has no effect when operating in FIPS mode.

A value of "0", "OFF" or "DISABLED" disables the SSL V2 protocol while a value of "1", "ON" or "ENABLED" enables the SSL V2 protocol. The default value is 'ON'.

Specifies whether the SSL V3 protocol is supported. This variable has no effect when operating in FIPS mode.

A value of "0", "OFF" or "DISABLED" disables the SSL V3 protocol while a value of "1", "ON" or "ENABLED" enables the SSL V3 protocol. The default value is 'ON'.

Specifies whether the TLS V1.0 protocol is supported.

A value of "0", "OFF" or "DISABLED" disables the TLS V1.0 protocol while a value of "1", "ON" or "ENABLED" enables the TLS V1.0 protocol. The default value is 'ON'.

Specifies whether the TLS V1.1 protocol is supported.

A value of "0", "OFF" or "DISABLED" disables the TLS V1.1 protocol while a value of "1", "ON" or "ENABLED" enables the TLS V1.1 protocol. The default value is 'OFF'.

A value of "NONE" disables SSL V3 and TLS handshake renegotiation as a server and allow RFC 5746 renegotiation. This is the default.

A value of "DISABLED" disables SSL V3 and TLS handshake renegotiation as a server and also disable RFC 5746 renegotiation.

A value of "ALL" allows SSL V3 and TLS handshake renegotiation as a server while also allowing RFC 5746 renegotiation.

A value of "ABBREVIATED" allows SSL V3 and TLS abbreviated handshake renegotiation as a server for resuming the current session only, while disabling SSL V3 and TLS full handshake renegotiation as a server. With this value specified, the System SSL session ID cache is not checked when resuming the current session. RFC 5746 renegotiation is allowed if this value is specified.

GSK_RENEGOTIATION_PEER_CERT_
CHECK

A value of "OFF" or "0" does not perform an identity check against the peer's certificate during renegotiation. This allows the peer certificate to change during renegotiation. This is the default.

A value of "ON" or "1" performs a comparison against the peer's certificate to ensure that certificate does not change during renegotiation.

Specifies whether the SSL random number generator, gsk_generate_random_bytes includes bytes with a zero value in the random byte output stream, or remove them.

The GSK_RNG_ALLOW_ZERO_BYTES environment variable is processed during System SSL initialization and is not checked afterward.

A value of “TRUE”, “ON” or “1” sets the random number generator to retain bytes with a zero value in the output stream. A value of “FALSE”, “OFF” or “0” results in bytes with a zero value being removed. The default setting is "TRUE".

Setting this environment variable to 1 causes a series of messages to be written to stderr during System SSL initialization. These messages displays the current status of the hardware cryptographic support. These messages are intended for diagnostic use only and are not translated based on the setting of the LANG environment variable.

Specify "1” to have messages written. Any other value is ignored, which is the default.

Setting this environment variable to 1 causes a message to be written to stderr when an ICSF callable service returns an error. These messages are intended for diagnostic use only and are not translated based on the setting of the LANG environment variable.

Specify "1” to have messages written. Any other value is ignored, which is the default.

Specifies the fully-qualified name of the file to receive standard error messages generated using SSL message services. Messages displayed from externally documented messages is written to stderr if this environment variable is not defined.

If fully qualified file not specified, the default action is to write standard errors to stderr.

Specifies the fully-qualified name of the file to receive standard output messages generated using SSL message services. Messages displayed from externally documented messages is written to stdout if this environment variable is not defined.

If fully qualified file not specified, the default action is to write standard output to stdout.

Specifies the Suite B profile to be applied to TLS sessions.

A Suite B compliant TLS V1.2 or later client must offer only the following cipher suites when conversing with a TLS V1.2 Suite B compliant server.

A value of "OFF" specifies that Suite B compliant profiles are not in use for TLS sessions. This is the default value.

A value of "128" specifies that only ciphers defined within 128-bit Suite B compliant profile can be used for a TLS session.

A value of "192" specifies that only ciphers defined within 192-bit Suite B compliant profile can be used for a TLS session.

A value of "ALL" specifies that ciphers defined within both the 128-bit and 192-bit Suite B compliant profiles can be used for a TLS session.

Specifies whether sysplex session caching is supported for this application.

A value of "0", "OFF" or "DISABLED" disables sysplex session caching while a value of "1", "ON" or "ENABLED" enables sysplex session caching. The default value is "OFF".

Specifies the character set for ASN.1 TELETEXSTRING conversions. The T.61 character set is supposed to be used for strings tagged as TELETEXSTRING. The X.690 ASN.1 definition specifies the 7-bit T.61character set (ISO IR-102). However, many certificate authorities issue certificates using the 8-bit ISO8859-1 character set (ISO IR-100) instead of the 7-bit T.61 character set. This causes conversion errors when the certificate is decoded. To add to the confusion, the 8-bit T.61 character set (ISO IR-103) is also used by some implementations.

If the GSK_T61_AS_LATIN1 environment variable is set to YES or 1, the 8-bit ISO8859-1 character set is used when processing a TELETEX string. If the GSK_T61_AS_LATIN1 environment variable is set to NO or 0, the 8-bit T.61 character set is used. The default is to use the ISO8859-1 character set. The GSK_T61_AS_LATIN1 environment variable is processed during System SSL initialization and is not checked afterward. Note that selecting the incorrect character set can cause strings to be converted incorrectly.

Specifies the list of hash and signature algorithm pair specifications supported by the client or server as a string consisting of 1 or more 4-character values in order of preference for use.

The signature algorithm pair specifications are sent by either the client or server to the session partner to indicate which signature/hash algorithm combinations are supported for digital signatures.

The signature algorithm pair specification only has relevance for sessions using TLS V1.2 or higher protocols.

See Table 6 for a list of valid 4-character signature algorithm pairs specifications.

Specifies a bit mask enabling System SSL trace options. No trace option is enabled if the bit mask is 0 and all trace options are enabled if the bit mask is 0xffff. The bit mask can be specified as a decimal (nnn), octal (0nnnn) or hexadecimal (0xhh) value.

These trace options are available:

• 0x01 = Trace function entry
• 0x02 = Trace function exit
• 0x04 = Trace errors
• 0x08 = Include informational messages
• 0x10 = Include EBCDIC data dumps
• 0x20 = Include ASCII data dumps

The default value is 0x00.

Specifies the name of the trace file. The gsktrace command is used to format the trace file. The trace file is not used if the GSK_TRACE environment variable is not defined or is set to 0.

The current process identifier is included as part of the trace file name when the name contains a percent sign (%). For example, if GSK_TRACE_FILE is set to /tmp/gskssl.%.trc and the current process identifier is 247, then the trace file name is /tmp/gskssl.247.trc.

Must be set to the name of an UNIX System Services file in a directory for which the executing application has write permission.

The default trace file is /tmp/gskssl.%.trc.

Specifies the SSL V2 cipher specifications in order of preference as a string consisting of 1 or more 1-character values.

See Table 1 for the list of the supported ciphers.

If Security Level 3 is installed, the default is "713642", otherwise, the default is "642".

Specifies the session timeout value in seconds for the SSL V2 protocol.

The valid timeout values are 0 through 100, default value is 100.

Specifies the number of session identifiers that can be contained in the SSL V2 cache.

The valid cache sizes are 0 through 32000 and defaults to 256. The SSL V2 cache is disabled if 0 is specified. The session identifier cache is allocated using the requested size rounded up to a power of 2 with a minimum size of 16.

Specifies the SSL V3 cipher specifications in order of preference as a string consisting of 1 or more 2-character values. The SSL V3 cipher specifications are used for the SSL V3, TLS V1.0, and higher protocols.

For protocols TLS V1.1 and above, export cipher suites is not used. 40-bit ciphers are ignored if these security protocols are negotiated.

For protocols TLS V1.2 and above, 56-bit DES cipher suites are not used. DES ciphers are ignored if these communications protocols are negotiated.

Any ciphers that use SHA-256 or greater message authentication or use AES-GCM encryption can only be used if TLS V1.2 or higher is the negotiated protocol.

See Table 2 for the list of the supported 2-character ciphers.

For protocols TLS V1.1 and above export cipher suites are not used. 40-bit ciphers are ignored if these security protocols are negotiated.

For protocols TLS V1.2 and above, 56-bit DES cipher suites are not used. DES ciphers are ignored if these communications protocols are negotiated.

Any ciphers that use SHA-256 or greater message authentication or use AES-GCM encryption can only be used if TLS V1.2 or higher is the negotiated protocol.

See Table 3 for the list of the supported 4-character ciphers.

Specifies the session timeout value in seconds for the SSL V3, TLS V1.0 and higher protocols.

The valid timeout values are 0 through 86400 and defaults to 86400. The timeout is disabled if 0 is specified.

Specifies the number of session identifiers that can be contained in the SSL V3 cache. The SSL V3 session cache is used for the SSL V3, TLS V1.0 and higher protocols.

The valid cache sizes are 0 through 64000 and defaults to 512. The SSL V3 cache is disabled if 0 is specified. The session identifier cache is allocated by using the requested size rounded up to a power of 2 with a minimum size of 16.

Used to control the size limit for a V2 session cache. This variable is for use only with the deprecated API set.

The valid cache sizes are 0 through 32000 and defaults to 256.

Used to control the size limit for a V3 session cache. This variable is for use only with the deprecated API set.

The valid cache sizes are 0 through 64000 and defaults to 512 entries.

The default location is /usr/lib/nls/msg/%L/%N:/usr/lib/nls/msg/ En_US.IBM-1047/%N