RFC 2078
Generic Security Service Application Program Interface, Version 2
2: Interface Descriptions This section describes the GSS-API's service interface, dividing the set of calls offered into four groups. Credential management calls are related to the acquisition and release of credentials by principals. Context-level calls are related to the management of security contexts between principals. Per-message calls are related
to the protection of individual messages on established security
contexts. Support calls provide ancillary functions useful to GSS-API
callers. Table 2 groups and summarizes the calls in tabular fashion.
Table 2: GSS-API Calls
CREDENTIAL MANAGEMENT
GSS_Acquire_cred acquire credentials for use
GSS_Release_cred release credentials after use
GSS_Inquire_cred display information about
credentials
GSS_Add_cred construct credentials incrementally
GSS_Inquire_cred_by_mech display per-mechanism credential
information
CONTEXT-LEVEL CALLS
GSS_Init_sec_context initiate outbound security context
GSS_Accept_sec_context accept inbound security context
GSS_Delete_sec_context flush context when no longer needed
GSS_Process_context_token process received control token on
context
GSS_Context_time indicate validity time remaining on
context
GSS_Inquire_context display information about context
GSS_Wrap_size_limit determine GSS_Wrap token size limit
GSS_Export_sec_context transfer context to other process
GSS_Import_sec_context import transferred context
PER-MESSAGE CALLS
GSS_GetMIC apply integrity check, receive as
token separate from message
GSS_VerifyMIC validate integrity check token
along with message
GSS_Wrap sign, optionally encrypt,
encapsulate
GSS_Unwrap decapsulate, decrypt if needed,
validate integrity check
SUPPORT CALLS
GSS_Display_status translate status codes to printable
form
GSS_Indicate_mechs indicate mech_types supported on
local system
GSS_Compare_name compare two names for equality
GSS_Display_name translate name to printable form
GSS_Import_name convert printable name to
normalized form
GSS_Release_name free storage of normalized-form
name
GSS_Release_buffer free storage of printable name
GSS_Release_OID free storage of OID object
GSS_Release_OID_set free storage of OID set object
GSS_Create_empty_OID_set create empty OID set
GSS_Add_OID_set_member add member to OID set
GSS_Test_OID_set_member test if OID is member of OID set
GSS_OID_to_str display OID as string
GSS_Str_to_OID construct OID from string
GSS_Inquire_names_for_mech indicate name types supported by
mechanism
GSS_Inquire_mechs_for_name indicates mechanisms supporting name
type
GSS_Canonicalize_name translate name to per-mechanism form
GSS_Export_name externalize per-mechanism name
GSS_Duplicate_name duplicate name object
2.1: Credential management calls
These GSS-API calls provide functions related to the management of
credentials. Their characterization with regard to whether or not
they may block pending exchanges with other network entities (e.g.,
directories or authentication servers) depends in part on OS-specific
(extra-GSS-API) issues, so is not specified in this document.
The GSS_Acquire_cred() call is defined within the GSS-API in support
of application portability, with a particular orientation towards
support of portable server applications. It is recognized that (for
certain systems and mechanisms) credentials for interactive users may
be managed differently from credentials for server processes; in such
environments, it is the GSS-API implementation's responsibility to
distinguish these cases and the procedures for making this
distinction are a local matter. The GSS_Release_cred() call provides
a means for callers to indicate to the GSS-API that use of a
credentials structure is no longer required. The GSS_Inquire_cred()
call allows callers to determine information about a credentials
structure. The GSS_Add_cred() call enables callers to append
elements to an existing credential structure, allowing iterative construction of a multi-mechanism credential. The GSS_Inquire_cred_by_mech() call enables callers to extract per- mechanism information describing a credentials structure. 2.1.1: GSS_Acquire_cred call Inputs: o desired_name INTERNAL NAME, -NULL requests locally-determined default o lifetime_req INTEGER,-in seconds; 0 requests default o desired_mechs SET OF OBJECT IDENTIFIER,-empty set requests system-selected default o cred_usage INTEGER -0=INITIATE-AND-ACCEPT, 1=INITIATE-ONLY, 2=ACCEPT-ONLY Outputs: o major_status INTEGER, o minor_status INTEGER, o output_cred_handle CREDENTIAL HANDLE, o actual_mechs SET OF OBJECT IDENTIFIER, o lifetime_rec INTEGER -in seconds, or reserved value for INDEFINITE Return major_status codes: o GSS_S_COMPLETE indicates that requested credentials were successfully established, for the duration indicated in lifetime_rec, suitable for the usage requested in cred_usage, for the set of mech_types indicated in actual_mechs, and that those credentials can be referenced for subsequent use with the handle returned in output_cred_handle. o GSS_S_BAD_MECH indicates that a mech_type unsupported by the GSS-API implementation type was requested, causing the credential establishment operation to fail.
o GSS_S_BAD_NAMETYPE indicates that the provided desired_name is
uninterpretable or of a type unsupported by the applicable
underlying GSS-API mechanism(s), so no credentials could be
established for the accompanying desired_name.
o GSS_S_BAD_NAME indicates that the provided desired_name is
inconsistent in terms of internally-incorporated type specifier
information, so no credentials could be established for the
accompanying desired_name.
o GSS_S_FAILURE indicates that credential establishment failed
for reasons unspecified at the GSS-API level, including lack
of authorization to establish and use credentials associated
with the identity named in the input desired_name argument.
GSS_Acquire_cred() is used to acquire credentials so that a
principal can (as a function of the input cred_usage parameter)
initiate and/or accept security contexts under the identity
represented by the desired_name input argument. On successful
completion, the returned output_cred_handle result provides a handle
for subsequent references to the acquired credentials. Typically,
single-user client processes requesting that default credential
behavior be applied for context establishment purposes will have no
need to invoke this call.
A caller may provide the value NULL for desired_name, signifying a
request for credentials corresponding to a principal identity
selected by default for the caller. The procedures used by GSS-API
implementations to select the appropriate principal identity in
response to such a request are local matters. It is possible that
multiple pre-established credentials may exist for the same principal
identity (for example, as a result of multiple user login sessions)
when GSS_Acquire_cred() is called; the means used in such cases to
select a specific credential are local matters. The input
lifetime_req argument to GSS_Acquire_cred() may provide useful
information for local GSS-API implementations to employ in making
this disambiguation in a manner which will best satisfy a caller's
intent.
The lifetime_rec result indicates the length of time for which the
acquired credentials will be valid, as an offset from the present. A
mechanism may return a reserved value indicating INDEFINITE if no
constraints on credential lifetime are imposed. A caller of
GSS_Acquire_cred() can request a length of time for which acquired
credentials are to be valid (lifetime_req argument), beginning at the
present, or can request credentials with a default validity interval.
(Requests for postdated credentials are not supported within the
GSS-API.) Certain mechanisms and implementations may bind in
credential validity period specifiers at a point preliminary to invocation of the GSS_Acquire_cred() call (e.g., in conjunction with user login procedures). As a result, callers requesting non-default values for lifetime_req must recognize that such requests cannot always be honored and must be prepared to accommodate the use of returned credentials with different lifetimes as indicated in lifetime_rec. The caller of GSS_Acquire_cred() can explicitly specify a set of mech_types which are to be accommodated in the returned credentials (desired_mechs argument), or can request credentials for a system- defined default set of mech_types. Selection of the system-specified default set is recommended in the interests of application portability. The actual_mechs return value may be interrogated by the caller to determine the set of mechanisms with which the returned credentials may be used. 2.1.2: GSS_Release_cred call Input: o cred_handle CREDENTIAL HANDLE - NULL specifies that the credential elements used when default credential behavior is requested be released. Outputs: o major_status INTEGER, o minor_status INTEGER Return major_status codes: o GSS_S_COMPLETE indicates that the credentials referenced by the input cred_handle were released for purposes of subsequent access by the caller. The effect on other processes which may be authorized shared access to such credentials is a local matter. o GSS_S_NO_CRED indicates that no release operation was performed, either because the input cred_handle was invalid or because the caller lacks authorization to access the referenced credentials. o GSS_S_FAILURE indicates that the release operation failed for reasons unspecified at the GSS-API level.
Provides a means for a caller to explicitly request that credentials be released when their use is no longer required. Note that system- specific credential management functions are also likely to exist, for example to assure that credentials shared among processes are properly deleted when all affected processes terminate, even if no explicit release requests are issued by those processes. Given the fact that multiple callers are not precluded from gaining authorized access to the same credentials, invocation of GSS_Release_cred() cannot be assumed to delete a particular set of credentials on a system-wide basis. 2.1.3: GSS_Inquire_cred call Input: o cred_handle CREDENTIAL HANDLE -NULL specifies that the credential elements used when default credential behavior is requested are to be queried Outputs: o major_status INTEGER, o minor_status INTEGER, o cred_name INTERNAL NAME, o lifetime_rec INTEGER -in seconds, or reserved value for INDEFINITE o cred_usage INTEGER, -0=INITIATE-AND-ACCEPT, 1=INITIATE-ONLY, 2=ACCEPT-ONLY o mech_set SET OF OBJECT IDENTIFIER Return major_status codes: o GSS_S_COMPLETE indicates that the credentials referenced by the input cred_handle argument were valid, and that the output cred_name, lifetime_rec, and cred_usage values represent, respectively, the credentials' associated principal name, remaining lifetime, suitable usage modes, and supported mechanism types. o GSS_S_NO_CRED indicates that no information could be returned about the referenced credentials, either because the input cred_handle was invalid or because the caller lacks authorization to access the referenced credentials.
o GSS_S_DEFECTIVE_CREDENTIAL indicates that the referenced
credentials are invalid.
o GSS_S_CREDENTIALS_EXPIRED indicates that the referenced
credentials have expired.
o GSS_S_FAILURE indicates that the operation failed for
reasons unspecified at the GSS-API level.
The GSS_Inquire_cred() call is defined primarily for the use of those
callers which request use of default credential behavior rather than
acquiring credentials explicitly with GSS_Acquire_cred(). It enables
callers to determine a credential structure's associated principal
name, remaining validity period, usability for security context
initiation and/or acceptance, and supported mechanisms.
For a multi-mechanism credential, the returned "lifetime" specifier
indicates the shortest lifetime of any of the mechanisms' elements in
the credential (for either context initiation or acceptance
purposes).
GSS_Inquire_cred() should indicate INITIATE-AND-ACCEPT for
"cred_usage" if both of the following conditions hold:
(1) there exists in the credential an element which allows context
initiation using some mechanism
(2) there exists in the credential an element which allows context
acceptance using some mechanism (allowably, but not necessarily,
one of the same mechanism(s) qualifying for (1)).
If condition (1) holds but not condition (2), GSS_Inquire_cred()
should indicate INITIATE-ONLY for "cred_usage". If condition (2)
holds but not condition (1), GSS_Inquire_cred() should indicate
ACCEPT-ONLY for "cred_usage".
Callers requiring finer disambiguation among available combinations
of lifetimes, usage modes, and mechanisms should call the
GSS_Inquire_cred_by_mech() routine, passing that routine one of the
mech OIDs returned by GSS_Inquire_cred().
2.1.4: GSS_Add_cred call Inputs: o input_cred_handle CREDENTIAL HANDLE - handle to credential structure created with prior GSS_Acquire_cred() or GSS_Add_cred() call, or NULL to append elements to the set which are applied for the caller when default credential behavior is specified. o desired_name INTERNAL NAME - NULL requests locally-determined default o initiator_time_req INTEGER - in seconds; 0 requests default o acceptor_time_req INTEGER - in seconds; 0 requests default o desired_mech OBJECT IDENTIFIER o cred_usage INTEGER - 0=INITIATE-AND-ACCEPT, 1=INITIATE-ONLY, 2=ACCEPT-ONLY Outputs: o major_status INTEGER, o minor_status INTEGER, o output_cred_handle CREDENTIAL HANDLE, - NULL to request that credential elements be added "in place" to the credential structure identified by input_cred_handle, non-NULL pointer to request that a new credential structure and handle be created. o actual_mechs SET OF OBJECT IDENTIFIER, o initiator_time_rec INTEGER - in seconds, or reserved value for INDEFINITE o acceptor_time_rec INTEGER - in seconds, or reserved value for INDEFINITE o cred_usage INTEGER, -0=INITIATE-AND-ACCEPT, 1=INITIATE-ONLY, 2=ACCEPT-ONLY o mech_set SET OF OBJECT IDENTIFIER -- full set of mechanisms supported by resulting credential.
Return major_status codes:
o GSS_S_COMPLETE indicates that the credentials referenced by
the input_cred_handle argument were valid, and that the
resulting credential from GSS_Add_cred() is valid for the
durations indicated in initiator_time_rec and acceptor_time_rec,
suitable for the usage requested in cred_usage, and for the
mechanisms indicated in actual_mechs.
o GSS_S_DUPLICATE_ELEMENT indicates that the input desired_mech
specified a mechanism for which the referenced credential
already contained a credential element with overlapping
cred_usage and validity time specifiers.
o GSS_S_BAD_MECH indicates that the input desired_mech specified
a mechanism unsupported by the GSS-API implementation, causing
the GSS_Add_cred() operation to fail.
o GSS_S_BAD_NAMETYPE indicates that the provided desired_name
is uninterpretable or of a type unsupported by the applicable
underlying GSS-API mechanism(s), so the GSS_Add_cred() operation
could not be performed for that name.
o GSS_S_BAD_NAME indicates that the provided desired_name is
inconsistent in terms of internally-incorporated type specifier
information, so the GSS_Add_cred() operation could not be
performed for that name.
o GSS_S_NO_CRED indicates that the input_cred_handle referenced
invalid or inaccessible credentials.
o GSS_S_FAILURE indicates that the operation failed for
reasons unspecified at the GSS-API level, including lack of
authorization to establish or use credentials representing
the requested identity.
GSS_Add_cred() enables callers to construct credentials iteratively
by adding credential elements in successive operations, corresponding
to different mechanisms. This offers particular value in multi-
mechanism environments, as the major_status and minor_status values
returned on each iteration are individually visible and can therefore
be interpreted unambiguously on a per-mechanism basis.
The same input desired_name, or default reference, should be used on
all GSS_Acquire_cred() and GSS_Add_cred() calls corresponding to a
particular credential.
2.1.5: GSS_Inquire_cred_by_mech call Inputs: o cred_handle CREDENTIAL HANDLE -- NULL specifies that the credential elements used when default credential behavior is requested are to be queried o mech_type OBJECT IDENTIFIER -- specific mechanism for which credentials are being queried Outputs: o major_status INTEGER, o minor_status INTEGER, o cred_name INTERNAL NAME, -- guaranteed to be MN o lifetime_rec_initiate INTEGER -- in seconds, or reserved value for INDEFINITE o lifetime_rec_accept INTEGER -- in seconds, or reserved value for INDEFINITE o cred_usage INTEGER, -0=INITIATE-AND-ACCEPT, 1=INITIATE-ONLY, 2=ACCEPT-ONLY Return major_status codes: o GSS_S_COMPLETE indicates that the credentials referenced by the input cred_handle argument were valid, that the mechanism indicated by the input mech_type was represented with elements within those credentials, and that the output cred_name, lifetime_rec_initiate, lifetime_rec_accept, and cred_usage values represent, respectively, the credentials' associated principal name, remaining lifetimes, and suitable usage modes. o GSS_S_NO_CRED indicates that no information could be returned about the referenced credentials, either because the input cred_handle was invalid or because the caller lacks authorization to access the referenced credentials. o GSS_S_DEFECTIVE_CREDENTIAL indicates that the referenced credentials are invalid. o GSS_S_CREDENTIALS_EXPIRED indicates that the referenced credentials have expired.
o GSS_S_BAD_MECH indicates that the referenced credentials do not
contain elements for the requested mechanism.
o GSS_S_FAILURE indicates that the operation failed for reasons
unspecified at the GSS-API level.
The GSS_Inquire_cred_by_mech() call enables callers in multi-
mechanism environments to acquire specific data about available
combinations of lifetimes, usage modes, and mechanisms within a
credential structure. The lifetime_rec_initiate result indicates the
available lifetime for context initiation purposes; the
lifetime_rec_accept result indicates the available lifetime for
context acceptance purposes.
2.2: Context-level calls
This group of calls is devoted to the establishment and management of
security contexts between peers. A context's initiator calls
GSS_Init_sec_context(), resulting in generation of a token which the
caller passes to the target. At the target, that token is passed to
GSS_Accept_sec_context(). Depending on the underlying mech_type and
specified options, additional token exchanges may be performed in the
course of context establishment; such exchanges are accommodated by
GSS_S_CONTINUE_NEEDED status returns from GSS_Init_sec_context() and
GSS_Accept_sec_context().
Either party to an established context may invoke
GSS_Delete_sec_context() to flush context information when a context
is no longer required. GSS_Process_context_token() is used to
process received tokens carrying context-level control information.
GSS_Context_time() allows a caller to determine the length of time
for which an established context will remain valid.
GSS_Inquire_context() returns status information describing context
characteristics. GSS_Wrap_size_limit() allows a caller to determine
the size of a token which will be generated by a GSS_Wrap()
operation. GSS_Export_sec_context() and GSS_Import_sec_context()
enable transfer of active contexts between processes on an end
system.
2.2.1: GSS_Init_sec_context call
Inputs:
o claimant_cred_handle CREDENTIAL HANDLE, -NULL specifies "use
default"
o input_context_handle CONTEXT HANDLE, -0 specifies "none assigned
yet"
o targ_name INTERNAL NAME,
o mech_type OBJECT IDENTIFIER, -NULL parameter specifies "use
default"
o deleg_req_flag BOOLEAN,
o mutual_req_flag BOOLEAN,
o replay_det_req_flag BOOLEAN,
o sequence_req_flag BOOLEAN,
o anon_req_flag BOOLEAN,
o lifetime_req INTEGER,-0 specifies default lifetime
o chan_bindings OCTET STRING,
o input_token OCTET STRING-NULL or token received from target
Outputs:
o major_status INTEGER,
o minor_status INTEGER,
o output_context_handle CONTEXT HANDLE,
o mech_type OBJECT IDENTIFIER, -actual mechanism always
indicated, never NULL
o output_token OCTET STRING, -NULL or token to pass to context
target
o deleg_state BOOLEAN,
o mutual_state BOOLEAN,
o replay_det_state BOOLEAN,
o sequence_state BOOLEAN,
o anon_state BOOLEAN,
o trans_state BOOLEAN,
o prot_ready_state BOOLEAN, -- see Section 1.2.7
o conf_avail BOOLEAN,
o integ_avail BOOLEAN,
o lifetime_rec INTEGER - in seconds, or reserved value for
INDEFINITE
This call may block pending network interactions for those mech_types
in which an authentication server or other network entity must be
consulted on behalf of a context initiator in order to generate an
output_token suitable for presentation to a specified target.
Return major_status codes:
o GSS_S_COMPLETE indicates that context-level information was
successfully initialized, and that the returned output_token
will provide sufficient information for the target to perform
per-message processing on the newly-established context.
o GSS_S_CONTINUE_NEEDED indicates that control information in the
returned output_token must be sent to the target, and that a
reply must be received and passed as the input_token argument
to a continuation call to GSS_Init_sec_context(), before
per-message processing can be performed in conjunction with
this context.
o GSS_S_DEFECTIVE_TOKEN indicates that consistency checks
performed on the input_token failed, preventing further
processing from being performed based on that token.
o GSS_S_DEFECTIVE_CREDENTIAL indicates that consistency checks
performed on the credential structure referenced by
claimant_cred_handle failed, preventing further processing from
being performed using that credential structure.
o GSS_S_BAD_SIG indicates that the received input_token
contains an incorrect integrity check, so context setup cannot
be accomplished.
o GSS_S_NO_CRED indicates that no context was established,
either because the input cred_handle was invalid, because the
referenced credentials are valid for context acceptor use
only, or because the caller lacks authorization to access the
referenced credentials.
o GSS_S_CREDENTIALS_EXPIRED indicates that the credentials
provided through the input claimant_cred_handle argument are no
longer valid, so context establishment cannot be completed.
o GSS_S_BAD_BINDINGS indicates that a mismatch between the
caller-provided chan_bindings and those extracted from the
input_token was detected, signifying a security-relevant
event and preventing context establishment. (This result will
be returned by GSS_Init_sec_context only for contexts where
mutual_state is TRUE.)
o GSS_S_OLD_TOKEN indicates that the input_token is too old to
be checked for integrity. This is a fatal error during context
establishment.
o GSS_S_DUPLICATE_TOKEN indicates that the input token has a
correct integrity check, but is a duplicate of a token already
processed. This is a fatal error during context establishment.
o GSS_S_NO_CONTEXT indicates that no valid context was recognized
for the input context_handle provided; this major status will
be returned only for successor calls following GSS_S_CONTINUE_
NEEDED status returns.
o GSS_S_BAD_NAMETYPE indicates that the provided targ_name is
of a type uninterpretable or unsupported by the applicable
underlying GSS-API mechanism(s), so context establishment
cannot be completed.
o GSS_S_BAD_NAME indicates that the provided targ_name is
inconsistent in terms of internally-incorporated type specifier
information, so context establishment cannot be accomplished.
o GSS_S_BAD_MECH indicates receipt of a context establishment token
or of a caller request specifying a mechanism unsupported by
the local system or with the caller's active credentials
o GSS_S_FAILURE indicates that context setup could not be
accomplished for reasons unspecified at the GSS-API level, and
that no interface-defined recovery action is available.
This routine is used by a context initiator, and ordinarily emits one
(or, for the case of a multi-step exchange, more than one)
output_token suitable for use by the target within the selected
mech_type's protocol. Using information in the credentials structure
referenced by claimant_cred_handle, GSS_Init_sec_context()
initializes the data structures required to establish a security
context with target targ_name. The targ_name may be any valid
INTERNAL NAME; it need not be an MN. The claimant_cred_handle must
correspond to the same valid credentials structure on the initial
call to GSS_Init_sec_context() and on any successor calls resulting
from GSS_S_CONTINUE_NEEDED status returns; different protocol
sequences modeled by the GSS_S_CONTINUE_NEEDED facility will require access to credentials at different points in the context establishment sequence. The input_context_handle argument is 0, specifying "not yet assigned", on the first GSS_Init_sec_context() call relating to a given context. If successful (i.e., if accompanied by major_status GSS_S_COMPLETE or GSS_S_CONTINUE_NEEDED), and only if successful, the initial GSS_Init_sec_context() call returns a non-zero output_context_handle for use in future references to this context. Once a non-zero output_context_handle has been returned, GSS-API callers should call GSS_Delete_sec_context() to release context- related resources if errors occur in later phases of context establishment, or when an established context is no longer required. When continuation attempts to GSS_Init_sec_context() are needed to perform context establishment, the previously-returned non-zero handle value is entered into the input_context_handle argument and will be echoed in the returned output_context_handle argument. On such continuation attempts (and only on continuation attempts) the input_token value is used, to provide the token returned from the context's target. The chan_bindings argument is used by the caller to provide information binding the security context to security-related characteristics (e.g., addresses, cryptographic keys) of the underlying communications channel. See Section 1.1.6 of this document for more discussion of this argument's usage. The input_token argument contains a message received from the target, and is significant only on a call to GSS_Init_sec_context() which follows a previous return indicating GSS_S_CONTINUE_NEEDED major_status. It is the caller's responsibility to establish a communications path to the target, and to transmit any returned output_token (independent of the accompanying returned major_status value) to the target over that path. The output_token can, however, be transmitted along with the first application-provided input message to be processed by GSS_GetMIC() or GSS_Wrap() in conjunction with a successfully- established context. The initiator may request various context-level functions through input flags: the deleg_req_flag requests delegation of access rights, the mutual_req_flag requests mutual authentication, the replay_det_req_flag requests that replay detection features be applied to messages transferred on the established context, and the sequence_req_flag requests that sequencing be enforced. (See Section
1.2.3 for more information on replay detection and sequencing features.) The anon_req_flag requests that the initiator's identity not be transferred within tokens to be sent to the acceptor. Not all of the optionally-requestable features will be available in all underlying mech_types. The corresponding return state values deleg_state, mutual_state, replay_det_state, and sequence_state indicate, as a function of mech_type processing capabilities and initiator-provided input flags, the set of features which will be active on the context. The returned trans_state value indicates whether the context is transferable to other processes through use of GSS_Export_sec_context(). These state indicators' values are undefined unless either the routine's major_status indicates GSS_S_COMPLETE, or TRUE prot_ready_state is returned along with GSS_S_CONTINUE_NEEDED major_status; for the latter case, it is possible that additional features, not confirmed or indicated along with TRUE prot_ready_state, will be confirmed and indicated when GSS_S_COMPLETE is subsequently returned. The returned anon_state and prot_ready_state values are significant for both GSS_S_COMPLETE and GSS_S_CONTINUE_NEEDED major_status returns from GSS_Init_sec_context(). When anon_state is returned TRUE, this indicates that neither the current token nor its predecessors delivers or has delivered the initiator's identity. Callers wishing to perform context establishment only if anonymity support is provided should transfer a returned token from GSS_Init_sec_context() to the peer only if it is accompanied by a TRUE anon_state indicator. When prot_ready_state is returned TRUE in conjunction with GSS_S_CONTINUE_NEEDED major_status, this indicates that per-message protection operations may be applied on the context: see Section 1.2.7 for further discussion of this facility. Failure to provide the precise set of features requested by the caller does not cause context establishment to fail; it is the caller's prerogative to delete the context if the feature set provided is unsuitable for the caller's use. The returned mech_type value indicates the specific mechanism employed on the context, is valid only along with major_status GSS_S_COMPLETE, and will never indicate the value for "default". Note that, for the case of certain mechanisms which themselves perform negotiation, the returned mech_type result may indicate selection of a mechanism identified by an OID different than that passed in the input mech_type argument. The conf_avail return value indicates whether the context supports per-message confidentiality services, and so informs the caller whether or not a request for encryption through the conf_req_flag
input to GSS_Wrap() can be honored. In similar fashion, the integ_avail return value indicates whether per-message integrity services are available (through either GSS_GetMIC() or GSS_Wrap()) on the established context. These state indicators' values are undefined unless either the routine's major_status indicates GSS_S_COMPLETE, or TRUE prot_ready_state is returned along with GSS_S_CONTINUE_NEEDED major_status. The lifetime_req input specifies a desired upper bound for the lifetime of the context to be established, with a value of 0 used to request a default lifetime. The lifetime_rec return value indicates the length of time for which the context will be valid, expressed as an offset from the present; depending on mechanism capabilities, credential lifetimes, and local policy, it may not correspond to the value requested in lifetime_req. If no constraints on context lifetime are imposed, this may be indicated by returning a reserved value representing INDEFINITE lifetime_req. The value of lifetime_rec is undefined unless the routine's major_status indicates GSS_S_COMPLETE. If the mutual_state is TRUE, this fact will be reflected within the output_token. A call to GSS_Accept_sec_context() at the target in conjunction with such a context will return a token, to be processed by a continuation call to GSS_Init_sec_context(), in order to achieve mutual authentication. 2.2.2: GSS_Accept_sec_context call Inputs: o acceptor_cred_handle CREDENTIAL HANDLE, -- NULL specifies "use default" o input_context_handle CONTEXT HANDLE, -- 0 specifies "not yet assigned" o chan_bindings OCTET STRING, o input_token OCTET STRING Outputs: o major_status INTEGER, o minor_status INTEGER, o src_name INTERNAL NAME, -- guaranteed to be MN
o mech_type OBJECT IDENTIFIER,
o output_context_handle CONTEXT HANDLE,
o deleg_state BOOLEAN,
o mutual_state BOOLEAN,
o replay_det_state BOOLEAN,
o sequence_state BOOLEAN,
o anon_state BOOLEAN,
o trans_state BOOLEAN,
o prot_ready_state BOOLEAN, -- see Section 1.2.7 for discussion
o conf_avail BOOLEAN,
o integ_avail BOOLEAN,
o lifetime_rec INTEGER, - in seconds, or reserved value for
INDEFINITE
o delegated_cred_handle CREDENTIAL HANDLE,
o output_token OCTET STRING -NULL or token to pass to context
initiator
This call may block pending network interactions for those mech_types
in which a directory service or other network entity must be
consulted on behalf of a context acceptor in order to validate a
received input_token.
Return major_status codes:
o GSS_S_COMPLETE indicates that context-level data structures
were successfully initialized, and that per-message processing
can now be performed in conjunction with this context.
o GSS_S_CONTINUE_NEEDED indicates that control information in the
returned output_token must be sent to the initiator, and that
a response must be received and passed as the input_token
argument to a continuation call to GSS_Accept_sec_context(),
before per-message processing can be performed in conjunction
with this context.
o GSS_S_DEFECTIVE_TOKEN indicates that consistency checks performed
on the input_token failed, preventing further processing from
being performed based on that token.
o GSS_S_DEFECTIVE_CREDENTIAL indicates that consistency checks
performed on the credential structure referenced by
acceptor_cred_handle failed, preventing further processing from
being performed using that credential structure.
o GSS_S_BAD_SIG indicates that the received input_token contains
an incorrect integrity check, so context setup cannot be
accomplished.
o GSS_S_DUPLICATE_TOKEN indicates that the integrity check on the
received input_token was correct, but that the input_token
was recognized as a duplicate of an input_token already
processed. No new context is established.
o GSS_S_OLD_TOKEN indicates that the integrity check on the received
input_token was correct, but that the input_token is too old
to be checked for duplication against previously-processed
input_tokens. No new context is established.
o GSS_S_NO_CRED indicates that no context was established, either
because the input cred_handle was invalid, because the
referenced credentials are valid for context initiator use
only, or because the caller lacks authorization to access the
referenced credentials.
o GSS_S_CREDENTIALS_EXPIRED indicates that the credentials provided
through the input acceptor_cred_handle argument are no
longer valid, so context establishment cannot be completed.
o GSS_S_BAD_BINDINGS indicates that a mismatch between the
caller-provided chan_bindings and those extracted from the
input_token was detected, signifying a security-relevant
event and preventing context establishment.
o GSS_S_NO_CONTEXT indicates that no valid context was recognized
for the input context_handle provided; this major status will
be returned only for successor calls following GSS_S_CONTINUE_
NEEDED status returns.
o GSS_S_BAD_MECH indicates receipt of a context establishment token
specifying a mechanism unsupported by the local system or with
the caller's active credentials.
o GSS_S_FAILURE indicates that context setup could not be
accomplished for reasons unspecified at the GSS-API level, and
that no interface-defined recovery action is available.
The GSS_Accept_sec_context() routine is used by a context target.
Using information in the credentials structure referenced by the
input acceptor_cred_handle, it verifies the incoming input_token and
(following the successful completion of a context establishment
sequence) returns the authenticated src_name and the mech_type used.
The returned src_name is guaranteed to be an MN, processed by the
mechanism under which the context was established. The
acceptor_cred_handle must correspond to the same valid credentials
structure on the initial call to GSS_Accept_sec_context() and on any
successor calls resulting from GSS_S_CONTINUE_NEEDED status returns;
different protocol sequences modeled by the GSS_S_CONTINUE_NEEDED
mechanism will require access to credentials at different points in
the context establishment sequence.
The input_context_handle argument is 0, specifying "not yet
assigned", on the first GSS_Accept_sec_context() call relating to a
given context. If successful (i.e., if accompanied by major_status
GSS_S_COMPLETE or GSS_S_CONTINUE_NEEDED), and only if successful, the
initial GSS_Accept_sec_context() call returns a non-zero
output_context_handle for use in future references to this context.
Once a non-zero output_context_handle has been returned, GSS-API
callers should call GSS_Delete_sec_context() to release context-
related resources if errors occur in later phases of context
establishment, or when an established context is no longer required.
The chan_bindings argument is used by the caller to provide
information binding the security context to security-related
characteristics (e.g., addresses, cryptographic keys) of the
underlying communications channel. See Section 1.1.6 of this document
for more discussion of this argument's usage.
The returned state results (deleg_state, mutual_state,
replay_det_state, sequence_state, anon_state, trans_state, and
prot_ready_state) reflect the same information as described for
GSS_Init_sec_context(), and their values are significant under the
same return state conditions.
The conf_avail return value indicates whether the context supports per-message confidentiality services, and so informs the caller whether or not a request for encryption through the conf_req_flag input to GSS_Wrap() can be honored. In similar fashion, the integ_avail return value indicates whether per-message integrity services are available (through either GSS_GetMIC() or GSS_Wrap()) on the established context. These values are significant under the same return state conditions as described under GSS_Init_sec_context(). The lifetime_rec return value is significant only in conjunction with GSS_S_COMPLETE major_status, and indicates the length of time for which the context will be valid, expressed as an offset from the present. The mech_type return value indicates the specific mechanism employed on the context, is valid only along with major_status GSS_S_COMPLETE, and will never indicate the value for "default". The delegated_cred_handle result is significant only when deleg_state is TRUE, and provides a means for the target to reference the delegated credentials. The output_token result, when non-NULL, provides a context-level token to be returned to the context initiator to continue a multi-step context establishment sequence. As noted with GSS_Init_sec_context(), any returned token should be transferred to the context's peer (in this case, the context initiator), independent of the value of the accompanying returned major_status. Note: A target must be able to distinguish a context-level input_token, which is passed to GSS_Accept_sec_context(), from the per-message data elements passed to GSS_VerifyMIC() or GSS_Unwrap(). These data elements may arrive in a single application message, and GSS_Accept_sec_context() must be performed before per-message processing can be performed successfully. 2.2.3: GSS_Delete_sec_context call Input: o context_handle CONTEXT HANDLE Outputs: o major_status INTEGER, o minor_status INTEGER,
o output_context_token OCTET STRING
Return major_status codes:
o GSS_S_COMPLETE indicates that the context was recognized, and that
relevant context-specific information was flushed. If the caller
provides a non-null buffer to receive an output_context_token, and
the mechanism returns a non-NULL token into that buffer, the
returned output_context_token is ready for transfer to the
context's peer.
o GSS_S_NO_CONTEXT indicates that no valid context was recognized
for the input context_handle provided, so no deletion was
performed.
o GSS_S_FAILURE indicates that the context is recognized, but
that the GSS_Delete_sec_context() operation could not be
performed for reasons unspecified at the GSS-API level.
This call may block pending network interactions for mech_types in
which active notification must be made to a central server when a
security context is to be deleted.
This call can be made by either peer in a security context, to flush
context-specific information. If a non-null output_context_token
parameter is provided by the caller, an output_context_token may be
returned to the caller. If an output_context_token is provided to
the caller, it can be passed to the context's peer to inform the
peer's GSS-API implementation that the peer's corresponding context
information can also be flushed. (Once a context is established, the
peers involved are expected to retain cached credential and context-
related information until the information's expiration time is
reached or until a GSS_Delete_sec_context() call is made.)
The facility for context_token usage to signal context deletion is
retained for compatibility with GSS-API Version 1. For current
usage, it is recommended that both peers to a context invoke
GSS_Delete_sec_context() independently, passing a null
output_context_token buffer to indicate that no context_token is
required. Implementations of GSS_Delete_sec_context() should delete
relevant locally-stored context information.
Attempts to perform per-message processing on a deleted context will
result in error returns.
2.2.4: GSS_Process_context_token call Inputs: o context_handle CONTEXT HANDLE, o input_context_token OCTET STRING Outputs: o major_status INTEGER, o minor_status INTEGER, Return major_status codes: o GSS_S_COMPLETE indicates that the input_context_token was successfully processed in conjunction with the context referenced by context_handle. o GSS_S_DEFECTIVE_TOKEN indicates that consistency checks performed on the received context_token failed, preventing further processing from being performed with that token. o GSS_S_NO_CONTEXT indicates that no valid context was recognized for the input context_handle provided. o GSS_S_FAILURE indicates that the context is recognized, but that the GSS_Process_context_token() operation could not be performed for reasons unspecified at the GSS-API level. This call is used to process context_tokens received from a peer once a context has been established, with corresponding impact on context-level state information. One use for this facility is processing of the context_tokens generated by GSS_Delete_sec_context(); GSS_Process_context_token() will not block pending network interactions for that purpose. Another use is to process tokens indicating remote-peer context establishment failures after the point where the local GSS-API implementation has already indicated GSS_S_COMPLETE status.
2.2.5: GSS_Context_time call Input: o context_handle CONTEXT HANDLE, Outputs: o major_status INTEGER, o minor_status INTEGER, o lifetime_rec INTEGER - in seconds, or reserved value for INDEFINITE Return major_status codes: o GSS_S_COMPLETE indicates that the referenced context is valid, and will remain valid for the amount of time indicated in lifetime_rec. o GSS_S_CONTEXT_EXPIRED indicates that data items related to the referenced context have expired. o GSS_S_CREDENTIALS_EXPIRED indicates that the context is recognized, but that its associated credentials have expired. o GSS_S_NO_CONTEXT indicates that no valid context was recognized for the input context_handle provided. o GSS_S_FAILURE indicates that the requested operation failed for reasons unspecified at the GSS-API level. This call is used to determine the amount of time for which a currently established context will remain valid. 2.2.6: GSS_Inquire_context call Input: o context_handle CONTEXT HANDLE, Outputs: o major_status INTEGER, o minor_status INTEGER,
o src_name INTERNAL NAME, -- name of context initiator,
-- guaranteed to be MN
o targ_name INTERNAL NAME, -- name of context target,
-- guaranteed to be MN
o lifetime_rec INTEGER -- in seconds, or reserved value for
INDEFINITE,
o mech_type OBJECT IDENTIFIER, -- the mechanism supporting this
security context
o deleg_state BOOLEAN,
o mutual_state BOOLEAN,
o replay_det_state BOOLEAN,
o sequence_state BOOLEAN,
o anon_state BOOLEAN,
o trans_state BOOLEAN,
o prot_ready_state BOOLEAN,
o conf_avail BOOLEAN,
o integ_avail BOOLEAN,
o locally_initiated BOOLEAN, -- TRUE if initiator, FALSE if acceptor
Return major_status codes:
o GSS_S_COMPLETE indicates that the referenced context is valid
and that src_name, targ_name, lifetime_rec, mech_type, deleg_state,
mutual_state, replay_det_state, sequence_state, anon_state,
trans_state, prot_ready_state, conf_avail, integ_avail, and
locally_initiated return values describe the corresponding
characteristics of the context.
o GSS_S_CONTEXT_EXPIRED indicates that the provided input
context_handle is recognized, but that the referenced context
has expired. Return values other than major_status and
minor_status are undefined.
o GSS_S_NO_CONTEXT indicates that no valid context was recognized
for the input context_handle provided. Return values other than
major_status and minor_status are undefined.
o GSS_S_FAILURE indicates that the requested operation failed for
reasons unspecified at the GSS-API level. Return values other than
major_status and minor_status are undefined.
This call is used to extract information describing characteristics
of a security context.
2.2.7: GSS_Wrap_size_limit call
Inputs:
o context_handle CONTEXT HANDLE,
o qop INTEGER,
o output_size INTEGER
Outputs:
o major_status INTEGER,
o minor_status INTEGER,
o max_input_size INTEGER
Return major_status codes:
o GSS_S_COMPLETE indicates a successful token size determination:
an input message with a length in octets equal to the
returned max_input_size value will, when passed to GSS_Wrap()
for processing on the context identified by the context_handle
parameter and with the quality of protection specifier provided
in the qop parameter, yield an output token no larger than the
value of the provided output_size parameter.
o GSS_S_CONTEXT_EXPIRED indicates that the provided input
context_handle is recognized, but that the referenced context
has expired. Return values other than major_status and
minor_status are undefined.
o GSS_S_NO_CONTEXT indicates that no valid context was recognized
for the input context_handle provided. Return values other than
major_status and minor_status are undefined.
o GSS_S_BAD_QOP indicates that the provided QOP value is not recognized or supported for the context. o GSS_S_FAILURE indicates that the requested operation failed for reasons unspecified at the GSS-API level. Return values other than major_status and minor_status are undefined. This call is used to determine the largest input datum which may be passed to GSS_Wrap() without yielding an output token larger than a caller-specified value. 2.2.8: GSS_Export_sec_context call Inputs: o context_handle CONTEXT HANDLE Outputs: o major_status INTEGER, o minor_status INTEGER, o interprocess_token OCTET STRING Return major_status codes: o GSS_S_COMPLETE indicates that the referenced context has been successfully exported to a representation in the interprocess_token, and is no longer available for use by the caller. o GSS_S_UNAVAILABLE indicates that the context export facility is not available for use on the referenced context. (This status should occur only for contexts for which the trans_state value is FALSE.) Return values other than major_status and minor_status are undefined. o GSS_S_CONTEXT_EXPIRED indicates that the provided input context_handle is recognized, but that the referenced context has expired. Return values other than major_status and minor_status are undefined. o GSS_S_NO_CONTEXT indicates that no valid context was recognized for the input context_handle provided. Return values other than major_status and minor_status are undefined.
o GSS_S_FAILURE indicates that the requested operation failed for reasons unspecified at the GSS-API level. Return values other than major_status and minor_status are undefined. This call generates an interprocess token for transfer to another process within an end system, in order to transfer control of a security context to that process. The recipient of the interprocess token will call GSS_Import_sec_context() to accept the transfer. The GSS_Export_sec_context() operation is defined for use only with security contexts which are fully and successfully established (i.e., those for which GSS_Init_sec_context() and GSS_Accept_sec_context() have returned GSS_S_COMPLETE major_status). To ensure portability, a caller of GSS_Export_sec_context() must not assume that a context may continue to be used once it has been exported; following export, the context referenced by the context_handle cannot be assumed to remain valid. Further, portable callers must not assume that a given interprocess token can be imported by GSS_Import_sec_context() more than once, thereby creating multiple instantiations of a single context. GSS-API implementations may detect and reject attempted multiple imports, but are not required to do so. The internal representation contained within the interprocess token is an implementation-defined local matter. Interprocess tokens cannot be assumed to be transferable across different GSS-API implementations. It is recommended that GSS-API implementations adopt policies suited to their operational environments in order to define the set of processes eligible to import a context, but specific constraints in this area are local matters. Candidate examples include transfers between processes operating on behalf of the same user identity, or processes comprising a common job. However, it may be impossible to enforce such policies in some implementations. In support of the above goals, implementations may protect the transferred context data by using cryptography to protect data within the interprocess token, or by using interprocess tokens as a means to reference local interprocess communication facilities (protected by other means) rather than storing the context data directly within the tokens. Transfer of an open context may, for certain mechanisms and implementations, reveal data about the credential which was used to establish the context. Callers should, therefore, be cautious about the trustworthiness of processes to which they transfer contexts. Although the GSS-API implementation may provide its own set of
protections over the exported context, the caller is responsible for protecting the interprocess token from disclosure, and for taking care that the context is transferred to an appropriate destination process. 2.2.9: GSS_Import_sec_context call Inputs: o interprocess_token OCTET STRING Outputs: o major_status INTEGER, o minor_status INTEGER, o context_handle CONTEXT HANDLE Return major_status codes: o GSS_S_COMPLETE indicates that the context represented by the input interprocess_token has been successfully transferred to the caller, and is available for future use via the output context_handle. o GSS_S_CONTEXT_EXPIRED indicates that the context represented by the input interprocess_token has expired. Return values other than major_status and minor_status are undefined. o GSS_S_NO_CONTEXT indicates that the context represented by the input interprocess_token was invalid. Return values other than major_status and minor_status are undefined. o GSS_S_DEFECTIVE_TOKEN indicates that the input interprocess_token was defective. Return values other than major_status and minor_status are undefined. o GSS_S_UNAVAILABLE indicates that the context import facility is not available for use on the referenced context. Return values other than major_status and minor_status are undefined. o GSS_S_UNAUTHORIZED indicates that the context represented by the input interprocess_token is unauthorized for transfer to the caller. Return values other than major_status and minor_status are undefined.
o GSS_S_FAILURE indicates that the requested operation failed for reasons unspecified at the GSS-API level. Return values other than major_status and minor_status are undefined. This call processes an interprocess token generated by GSS_Export_sec_context(), making the transferred context available for use by the caller. After a successful GSS_Import_sec_context() operation, the imported context is available for use by the importing process. For further discussion of the security and authorization issues regarding this call, please see the discussion in Section 2.2.8. 2.3: Per-message calls This group of calls is used to perform per-message protection processing on an established security context. None of these calls block pending network interactions. These calls may be invoked by a context's initiator or by the context's target. The four members of this group should be considered as two pairs; the output from GSS_GetMIC() is properly input to GSS_VerifyMIC(), and the output from GSS_Wrap() is properly input to GSS_Unwrap(). GSS_GetMIC() and GSS_VerifyMIC() support data origin authentication and data integrity services. When GSS_GetMIC() is invoked on an input message, it yields a per-message token containing data items which allow underlying mechanisms to provide the specified security services. The original message, along with the generated per-message token, is passed to the remote peer; these two data elements are processed by GSS_VerifyMIC(), which validates the message in conjunction with the separate token. GSS_Wrap() and GSS_Unwrap() support caller-requested confidentiality in addition to the data origin authentication and data integrity services offered by GSS_GetMIC() and GSS_VerifyMIC(). GSS_Wrap() outputs a single data element, encapsulating optionally enciphered user data as well as associated token data items. The data element output from GSS_Wrap() is passed to the remote peer and processed by GSS_Unwrap() at that system. GSS_Unwrap() combines decipherment (as required) with validation of data items related to authentication and integrity.
2.3.1: GSS_GetMIC call Note: This call is functionally equivalent to the GSS_Sign call as defined in previous versions of this specification. In the interests of backward compatibility, it is recommended that implementations support this function under both names for the present; future references to this function as GSS_Sign are deprecated. Inputs: o context_handle CONTEXT HANDLE, o qop_req INTEGER,-0 specifies default QOP o message OCTET STRING Outputs: o major_status INTEGER, o minor_status INTEGER, o per_msg_token OCTET STRING Return major_status codes: o GSS_S_COMPLETE indicates that an integrity check, suitable for an established security context, was successfully applied and that the message and corresponding per_msg_token are ready for transmission. o GSS_S_CONTEXT_EXPIRED indicates that context-related data items have expired, so that the requested operation cannot be performed. o GSS_S_CREDENTIALS_EXPIRED indicates that the context is recognized, but that its associated credentials have expired, so that the requested operation cannot be performed. o GSS_S_NO_CONTEXT indicates that no valid context was recognized for the input context_handle provided. o GSS_S_BAD_QOP indicates that the provided QOP value is not recognized or supported for the context. o GSS_S_FAILURE indicates that the context is recognized, but that the requested operation could not be performed for reasons unspecified at the GSS-API level.
Using the security context referenced by context_handle, apply an integrity check to the input message (along with timestamps and/or other data included in support of mech_type-specific mechanisms) and return the result in per_msg_token. The qop_req parameter, interpretation of which is discussed in Section 1.2.4, allows quality-of-protection control. The caller passes the message and the per_msg_token to the target. The GSS_GetMIC() function completes before the message and per_msg_token is sent to the peer; successful application of GSS_GetMIC() does not guarantee that a corresponding GSS_VerifyMIC() has been (or can necessarily be) performed successfully when the message arrives at the destination. Mechanisms which do not support per-message protection services should return GSS_S_FAILURE if this routine is called. 2.3.2: GSS_VerifyMIC call Note: This call is functionally equivalent to the GSS_Verify call as defined in previous versions of this specification. In the interests of backward compatibility, it is recommended that implementations support this function under both names for the present; future references to this function as GSS_Verify are deprecated. Inputs: o context_handle CONTEXT HANDLE, o message OCTET STRING, o per_msg_token OCTET STRING Outputs: o qop_state INTEGER, o major_status INTEGER, o minor_status INTEGER, Return major_status codes: o GSS_S_COMPLETE indicates that the message was successfully verified.
o GSS_S_DEFECTIVE_TOKEN indicates that consistency checks performed
on the received per_msg_token failed, preventing
further processing from being performed with that token.
o GSS_S_BAD_SIG indicates that the received per_msg_token contains
an incorrect integrity check for the message.
o GSS_S_DUPLICATE_TOKEN, GSS_S_OLD_TOKEN, GSS_S_UNSEQ_TOKEN,
and GSS_S_GAP_TOKEN values appear in conjunction with the
optional per-message replay detection features described
in Section 1.2.3; their semantics are described in that section.
o GSS_S_CONTEXT_EXPIRED indicates that context-related data
items have expired, so that the requested operation cannot be
performed.
o GSS_S_CREDENTIALS_EXPIRED indicates that the context is
recognized,
but that its associated credentials have expired, so
that the requested operation cannot be performed.
o GSS_S_NO_CONTEXT indicates that no valid context was recognized
for the input context_handle provided.
o GSS_S_FAILURE indicates that the context is recognized, but
that the GSS_VerifyMIC() operation could not be performed for
reasons unspecified at the GSS-API level.
Using the security context referenced by context_handle, verify that
the input per_msg_token contains an appropriate integrity check for
the input message, and apply any active replay detection or
sequencing features. Return an indication of the quality-of-
protection applied to the processed message in the qop_state result.
Since the GSS_VerifyMIC() routine never provides a confidentiality
service, its implementations should not return non-zero values in the
confidentiality fields of the output qop_state.
Mechanisms which do not support per-message protection services
should return GSS_S_FAILURE if this routine is called.
2.3.3: GSS_Wrap call
Note: This call is functionally equivalent to the GSS_Seal call as
defined in previous versions of this specification. In the interests
of backward compatibility, it is recommended that implementations
support this function under both names for the present; future
references to this function as GSS_Seal are deprecated.
Inputs:
o context_handle CONTEXT HANDLE,
o conf_req_flag BOOLEAN,
o qop_req INTEGER,-0 specifies default QOP
o input_message OCTET STRING
Outputs:
o major_status INTEGER,
o minor_status INTEGER,
o conf_state BOOLEAN,
o output_message OCTET STRING
Return major_status codes:
o GSS_S_COMPLETE indicates that the input_message was successfully
processed and that the output_message is ready for
transmission.
o GSS_S_CONTEXT_EXPIRED indicates that context-related data
items have expired, so that the requested operation cannot be
performed.
o GSS_S_CREDENTIALS_EXPIRED indicates that the context is
recognized,
but that its associated credentials have expired, so
that the requested operation cannot be performed.
o GSS_S_NO_CONTEXT indicates that no valid context was recognized
for the input context_handle provided.
o GSS_S_BAD_QOP indicates that the provided QOP value is not
recognized or supported for the context.
o GSS_S_FAILURE indicates that the context is recognized, but
that the GSS_Wrap() operation could not be performed for
reasons unspecified at the GSS-API level.
Performs the data origin authentication and data integrity functions
of GSS_GetMIC(). If the input conf_req_flag is TRUE, requests that
confidentiality be applied to the input_message. Confidentiality may
not be supported in all mech_types or by all implementations; the returned conf_state flag indicates whether confidentiality was provided for the input_message. The qop_req parameter, interpretation of which is discussed in Section 1.2.4, allows quality-of-protection control. In all cases, the GSS_Wrap() call yields a single output_message data element containing (optionally enciphered) user data as well as control information. Mechanisms which do not support per-message protection services should return GSS_S_FAILURE if this routine is called. 2.3.4: GSS_Unwrap call Note: This call is functionally equivalent to the GSS_Unseal call as defined in previous versions of this specification. In the interests of backward compatibility, it is recommended that implementations support this function under both names for the present; future references to this function as GSS_Unseal are deprecated. Inputs: o context_handle CONTEXT HANDLE, o input_message OCTET STRING Outputs: o conf_state BOOLEAN, o qop_state INTEGER, o major_status INTEGER, o minor_status INTEGER, o output_message OCTET STRING Return major_status codes: o GSS_S_COMPLETE indicates that the input_message was successfully processed and that the resulting output_message is available. o GSS_S_DEFECTIVE_TOKEN indicates that consistency checks performed on the per_msg_token extracted from the input_message failed, preventing further processing from being performed.
o GSS_S_BAD_SIG indicates that an incorrect integrity check was
detected
for the message.
o GSS_S_DUPLICATE_TOKEN, GSS_S_OLD_TOKEN, GSS_S_UNSEQ_TOKEN,
and GSS_S_GAP_TOKEN values appear in conjunction with the
optional per-message replay detection features described
in Section 1.2.3; their semantics are described in that section.
o GSS_S_CONTEXT_EXPIRED indicates that context-related data
items have expired, so that the requested operation cannot be
performed.
o GSS_S_CREDENTIALS_EXPIRED indicates that the context is
recognized,
but that its associated credentials have expired, so
that the requested operation cannot be performed.
o GSS_S_NO_CONTEXT indicates that no valid context was recognized
for the input context_handle provided.
o GSS_S_FAILURE indicates that the context is recognized, but
that the GSS_Unwrap() operation could not be performed for
reasons unspecified at the GSS-API level.
Processes a data element generated (and optionally enciphered) by
GSS_Wrap(), provided as input_message. The returned conf_state value
indicates whether confidentiality was applied to the input_message.
If conf_state is TRUE, GSS_Unwrap() deciphers the input_message.
Returns an indication of the quality-of-protection applied to the
processed message in the qop_state result. GSS_Wrap() performs the
data integrity and data origin authentication checking functions of
GSS_VerifyMIC() on the plaintext data. Plaintext data is returned in
output_message.
Mechanisms which do not support per-message protection services
should return GSS_S_FAILURE if this routine is called.
(page 59 continued on part 3)
