7 Network Working Group J. Wray
8 Request for Comments: 1509 Digital Equipment Corporation
12 Generic Security Service API : C-bindings
16 This RFC specifies an Internet standards track protocol for the
17 Internet community, and requests discussion and suggestions for
18 improvements. Please refer to the current edition of the "Internet
19 Official Protocol Standards" for the standardization state and status
20 of this protocol. Distribution of this memo is unlimited.
24 This document specifies C language bindings for the Generic Security
25 Service Application Program Interface (GSS-API), which is described
26 at a language-independent conceptual level in other documents.
28 The Generic Security Service Application Programming Interface (GSS-
29 API) provides security services to its callers, and is intended for
30 implementation atop alternative underlying cryptographic mechanisms.
31 Typically, GSS-API callers will be application protocols into which
32 security enhancements are integrated through invocation of services
33 provided by the GSS-API. The GSS-API allows a caller application to
34 authenticate a principal identity associated with a peer application,
35 to delegate rights to a peer, and to apply security services such as
36 confidentiality and integrity on a per-message basis.
40 The Generic Security Service Application Programming Interface [1]
41 provides security services to calling applications. It allows a
42 communicating application to authenticate the user associated with
43 another application, to delegate rights to another application, and
44 to apply security services such as confidentiality and integrity on a
47 There are four stages to using the GSSAPI:
49 (a) The application acquires a set of credentials with which it may
50 prove its identity to other processes. The application's
51 credentials vouch for its global identity, which may or may not
52 be related to the local username under which it is running.
60 RFC 1509 GSSAPI - Overview and C bindings September 1993
63 (b) A pair of communicating applications establish a joint security
64 context using their credentials. The security context is a
65 pair of GSSAPI data structures that contain shared state
66 information, which is required in order that per-message
67 security services may be provided. As part of the
68 establishment of a security context, the context initiator is
69 authenticated to the responder, and may require that the
70 responder is authenticated in turn. The initiator may
71 optionally give the responder the right to initiate further
72 security contexts. This transfer of rights is termed
73 delegation, and is achieved by creating a set of credentials,
74 similar to those used by the originating application, but which
75 may be used by the responder. To establish and maintain the
76 shared information that makes up the security context, certain
77 GSSAPI calls will return a token data structure, which is a
78 cryptographically protected opaque data type. The caller of
79 such a GSSAPI routine is responsible for transferring the token
80 to the peer application, which should then pass it to a
81 corresponding GSSAPI routine which will decode it and extract
84 (c) Per-message services are invoked to apply either:
86 (i) integrity and data origin authentication, or
88 (ii) confidentiality, integrity and data origin authentication
89 to application data, which are treated by GSSAPI as
90 arbitrary octet-strings. The application transmitting a
91 message that it wishes to protect will call the appropriate
92 GSSAPI routine (sign or seal) to apply protection, specifying
93 the appropriate security context, and send the result to the
94 receiving application. The receiver will pass the received
95 data to the corresponding decoding routine (verify or unseal)
96 to remove the protection and validate the data.
98 (d) At the completion of a communications session (which may extend
99 across several connections), the peer applications call GSSAPI
100 routines to delete the security context. Multiple contexts may
101 also be used (either successively or simultaneously) within a
102 single communications association.
106 This section lists the functions performed by each of the GSSAPI
107 routines and discusses their major parameters, describing how they
108 are to be passed to the routines. The routines are listed in figure
116 RFC 1509 GSSAPI - Overview and C bindings September 1993
119 Figure 4-1 GSSAPI Routines
124 gss_acquire_cred Assume a global identity
126 gss_release_cred Discard credentials
128 gss_init_sec_context Initiate a security context
129 with a peer application
131 gss_accept_sec_context Accept a security context
135 gss_process_context_token Process a token on a security
139 gss_delete_sec_context Discard a security context
141 gss_context_time Determine for how long a
142 context will remain valid
144 gss_sign Sign a message; integrity
147 gss_verify Check signature on a message
149 gss_seal Sign (optionally encrypt) a
150 message; confidentiality
153 gss_unseal Verify (optionally decrypt)
156 gss_display_status Convert an API status code
159 gss_indicate_mechs Determine underlying
160 authentication mechanism
162 gss_compare_name Compare two internal-form
165 gss_display_name Convert opaque name to text
172 RFC 1509 GSSAPI - Overview and C bindings September 1993
175 gss_import_name Convert a textual name to
178 gss_release_name Discard an internal-form
181 gss_release_buffer Discard a buffer
183 gss_release_oid_set Discard a set of object
186 gss_inquire_cred Determine information about
189 Individual GSSAPI implementations may augment these routines by
190 providing additional mechanism-specific routines if required
191 functionality is not available from the generic forms. Applications
192 are encouraged to use the generic routines wherever possible on
195 2.1. Data Types and Calling Conventions
197 The following conventions are used by the GSSAPI:
199 2.1.1. Structured data types
201 Wherever these GSSAPI C-bindings describe structured data, only
202 fields that must be provided by all GSSAPI implementation are
203 documented. Individual implementations may provide additional
204 fields, either for internal use within GSSAPI routines, or for use by
205 non-portable applications.
209 GSSAPI defines the following integer data type:
211 OM_uint32 32-bit unsigned integer
213 Where guaranteed minimum bit-count is important, this portable data
214 type is used by the GSSAPI routine definitions. Individual GSSAPI
215 implementations will include appropriate typedef definitions to map
216 this type onto a built-in data type.
218 2.1.3. String and similar data
220 Many of the GSSAPI routines take arguments and return values that
221 describe contiguous multiple-byte data. All such data is passed
222 between the GSSAPI and the caller using the gss_buffer_t data type.
228 RFC 1509 GSSAPI - Overview and C bindings September 1993
231 This data type is a pointer to a buffer descriptor, which consists of
232 a length field that contains the total number of bytes in the datum,
233 and a value field which contains a pointer to the actual datum:
235 typedef struct gss_buffer_desc_struct {
238 } gss_buffer_desc, *gss_buffer_t;
240 Storage for data passed to the application by a GSSAPI routine using
241 the gss_buffer_t conventions is allocated by the GSSAPI routine. The
242 application may free this storage by invoking the gss_release_buffer
243 routine. Allocation of the gss_buffer_desc object is always the
244 responsibility of the application; Unused gss_buffer_desc objects
245 may be initialized to the value GSS_C_EMPTY_BUFFER.
247 2.1.3.1. Opaque data types
249 Certain multiple-word data items are considered opaque data types at
250 the GSSAPI, because their internal structure has no significance
251 either to the GSSAPI or to the caller. Examples of such opaque data
252 types are the input_token parameter to gss_init_sec_context (which is
253 opaque to the caller), and the input_message parameter to gss_seal
254 (which is opaque to the GSSAPI). Opaque data is passed between the
255 GSSAPI and the application using the gss_buffer_t datatype.
257 2.1.3.2. Character strings
259 Certain multiple-word data items may be regarded as simple ISO
260 Latin-1 character strings. An example of this is the
261 input_name_buffer parameter to gss_import_name. Some GSSAPI routines
262 also return character strings. Character strings are passed between
263 the application and the GSSAPI using the gss_buffer_t datatype,
266 2.1.4. Object Identifiers
268 Certain GSSAPI procedures take parameters of the type gss_OID, or
269 Object identifier. This is a type containing ISO-defined tree-
270 structured values, and is used by the GSSAPI caller to select an
271 underlying security mechanism. A value of type gss_OID has the
274 typedef struct gss_OID_desc_struct {
277 } gss_OID_desc, *gss_OID;
284 RFC 1509 GSSAPI - Overview and C bindings September 1993
287 The elements field of this structure points to the first byte of an
288 octet string containing the ASN.1 BER encoding of the value of the
289 gss_OID. The length field contains the number of bytes in this
290 value. For example, the gss_OID value corresponding to {iso(1)
291 identified- oganization(3) icd-ecma(12) member-company(2) dec(1011)
292 cryptoAlgorithms(7) SPX(5)} meaning SPX (Digital's X.509
293 authentication mechanism) has a length field of 7 and an elements
294 field pointing to seven octets containing the following octal values:
295 53,14,2,207,163,7,5. GSSAPI implementations should provide constant
296 gss_OID values to allow callers to request any supported mechanism,
297 although applications are encouraged on portability grounds to accept
298 the default mechanism. gss_OID values should also be provided to
299 allow applications to specify particular name types (see section
300 2.1.10). Applications should treat gss_OID_desc values returned by
301 GSSAPI routines as read-only. In particular, the application should
302 not attempt to deallocate them. The gss_OID_desc datatype is
303 equivalent to the X/Open OM_object_identifier datatype [2].
305 2.1.5. Object Identifier Sets
307 Certain GSSAPI procedures take parameters of the type gss_OID_set.
308 This type represents one or more object identifiers (section 2.1.4).
309 A gss_OID_set object has the following structure:
311 typedef struct gss_OID_set_desc_struct {
314 } gss_OID_set_desc, *gss_OID_set;
316 The count field contains the number of OIDs within the set. The
317 elements field is a pointer to an array of gss_OID_desc objects, each
318 of which describes a single OID. gss_OID_set values are used to name
319 the available mechanisms supported by the GSSAPI, to request the use
320 of specific mechanisms, and to indicate which mechanisms a given
321 credential supports. Storage associated with gss_OID_set values
322 returned to the application by the GSSAPI may be deallocated by the
323 gss_release_oid_set routine.
327 A credential handle is a caller-opaque atomic datum that identifies a
328 GSSAPI credential data structure. It is represented by the caller-
329 opaque type gss_cred_id_t, which may be implemented as either an
330 arithmetic or a pointer type. Credentials describe a principal, and
331 they give their holder the ability to act as that principal. The
332 GSSAPI does not make the actual credentials available to
333 applications; instead the credential handle is used to identify a
334 particular credential, held internally by GSSAPI or underlying
340 RFC 1509 GSSAPI - Overview and C bindings September 1993
343 mechanism. Thus the credential handle contains no security-relavent
344 information, and requires no special protection by the application.
345 Depending on the implementation, a given credential handle may refer
346 to different credentials when presented to the GSSAPI by different
347 callers. Individual GSSAPI implementations should define both the
348 scope of a credential handle and the scope of a credential itself
349 (which must be at least as wide as that of a handle). Possibilities
350 for credential handle scope include the process that acquired the
351 handle, the acquiring process and its children, or all processes
352 sharing some local identification information (e.g., UID). If no
353 handles exist by which a given credential may be reached, the GSSAPI
354 may delete the credential.
356 Certain routines allow credential handle parameters to be omitted to
357 indicate the use of a default credential. The mechanism by which a
358 default credential is established and its scope should be defined by
359 the individual GSSAPI implementation.
363 The gss_ctx_id_t data type contains a caller-opaque atomic value that
364 identifies one end of a GSSAPI security context. It may be
365 implemented as either an arithmetic or a pointer type. Depending on
366 the implementation, a given gss_ctx_id_t value may refer to different
367 GSSAPI security contexts when presented to the GSSAPI by different
368 callers. The security context holds state information about each end
369 of a peer communication, including cryptographic state information.
370 Individual GSSAPI implementations should define the scope of a
371 context. Since no way is provided by which a new gss_ctx_id_t value
372 may be obtained for an existing context, the scope of a context
373 should be the same as the scope of a gss_ctx_id_t.
375 2.1.8. Authentication tokens
377 A token is a caller-opaque type that GSSAPI uses to maintain
378 synchronization between the context data structures at each end of a
379 GSSAPI security context. The token is a cryptographically protected
380 bit-string, generated by the underlying mechanism at one end of a
381 GSSAPI security context for use by the peer mechanism at the other
382 end. Encapsulation (if required) and transfer of the token are the
383 responsibility of the peer applications. A token is passed between
384 the GSSAPI and the application using the gss_buffer_t conventions.
388 One or more status codes are returned by each GSSAPI routine. Two
389 distinct sorts of status codes are returned. These are termed GSS
390 status codes and Mechanism status codes.
396 RFC 1509 GSSAPI - Overview and C bindings September 1993
399 2.1.9.1. GSS status codes
401 GSSAPI routines return GSS status codes as their OM_uint32 function
402 value. These codes indicate errors that are independent of the
403 underlying mechanism used to provide the security service. The
404 errors that can be indicated via a GSS status code are either generic
405 API routine errors (errors that are defined in the GSSAPI
406 specification) or calling errors (errors that are specific to these
409 A GSS status code can indicate a single fatal generic API error from
410 the routine and a single calling error. In addition, supplementary
411 status information may be indicated via the setting of bits in the
412 supplementary info field of a GSS status code.
414 These errors are encoded into the 32-bit GSS status code as follows:
417 |------------------------------------------------------------|
418 | Calling Error | Routine Error | Supplementary Info |
419 |------------------------------------------------------------|
422 Hence if a GSSAPI routine returns a GSS status code whose upper 16
423 bits contain a non-zero value, the call failed. If the calling error
424 field is non-zero, the invoking application's call of the routine was
425 erroneous. Calling errors are defined in table 5-1. If the routine
426 error field is non-zero, the routine failed for one of the routine-
427 specific reasons listed below in table 5-2. Whether or not the upper
428 16 bits indicate a failure or a success, the routine may indicate
429 additional information by setting bits in the supplementary info
430 field of the status code. The meaning of individual bits is listed
433 Table 5-1 Calling Errors
435 Name Value in Meaning
437 GSS_S_CALL_INACCESSIBLE_READ 1 A required input
440 GSS_S_CALL_INACCESSIBLE_WRITE 2 A required output
443 GSS_S_CALL_BAD_STRUCTURE 3 A parameter was
452 RFC 1509 GSSAPI - Overview and C bindings September 1993
455 Table 5-2 Routine Errors
457 Name Value in Meaning
460 GSS_S_BAD_MECH 1 An unsupported mechanism was
462 GSS_S_BAD_NAME 2 An invalid name was supplied
463 GSS_S_BAD_NAMETYPE 3 A supplied name was of an
465 GSS_S_BAD_BINDINGS 4 Incorrect channel bindings
467 GSS_S_BAD_STATUS 5 An invalid status code was
470 GSS_S_BAD_SIG 6 A token had an invalid
472 GSS_S_NO_CRED 7 No credentials were supplied
473 GSS_S_NO_CONTEXT 8 No context has been
475 GSS_S_DEFECTIVE_TOKEN 9 A token was invalid
476 GSS_S_DEFECTIVE_CREDENTIAL 10 A credential was invalid
477 GSS_S_CREDENTIALS_EXPIRED 11 The referenced credentials
479 GSS_S_CONTEXT_EXPIRED 12 The context has expired
480 GSS_S_FAILURE 13 Miscellaneous failure
483 Table 5-3 Supplementary Status Bits
485 Name Bit Number Meaning
486 GSS_S_CONTINUE_NEEDED 0 (LSB) The routine must be called
487 again to complete its
489 See routine documentation for
490 detailed description.
491 GSS_S_DUPLICATE_TOKEN 1 The token was a duplicate of
493 GSS_S_OLD_TOKEN 2 The token's validity period
495 GSS_S_UNSEQ_TOKEN 3 A later token has already been
498 The routine documentation also uses the name GSS_S_COMPLETE, which is
499 a zero value, to indicate an absence of any API errors or
500 supplementary information bits.
508 RFC 1509 GSSAPI - Overview and C bindings September 1993
511 All GSS_S_xxx symbols equate to complete OM_uint32 status codes,
512 rather than to bitfield values. For example, the actual value of the
513 symbol GSS_S_BAD_NAMETYPE (value 3 in the routine error field) is 3
516 The macros GSS_CALLING_ERROR(), GSS_ROUTINE_ERROR() and
517 GSS_SUPPLEMENTARY_INFO() are provided, each of which takes a GSS
518 status code and removes all but the relevant field. For example, the
519 value obtained by applying GSS_ROUTINE_ERROR to a status code removes
520 the calling errors and supplementary info fields, leaving only the
521 routine errors field. The values delivered by these macros may be
522 directly compared with a GSS_S_xxx symbol of the appropriate type.
523 The macro GSS_ERROR() is also provided, which when applied to a GSS
524 status code returns a non-zero value if the status code indicated a
525 calling or routine error, and a zero value otherwise.
527 A GSSAPI implementation may choose to signal calling errors in a
528 platform-specific manner instead of, or in addition to the routine
529 value; routine errors and supplementary info should be returned via
530 routine status values only.
532 2.1.9.2. Mechanism-specific status codes
534 GSSAPI routines return a minor_status parameter, which is used to
535 indicate specialized errors from the underlying security mechanism.
536 This parameter may contain a single mechanism-specific error,
537 indicated by a OM_uint32 value.
539 The minor_status parameter will always be set by a GSSAPI routine,
540 even if it returns a calling error or one of the generic API errors
541 indicated above as fatal, although other output parameters may remain
542 unset in such cases. However, output parameters that are expected to
543 return pointers to storage allocated by a routine must always set set
544 by the routine, even in the event of an error, although in such cases
545 the GSSAPI routine may elect to set the returned parameter value to
546 NULL to indicate that no storage was actually allocated. Any length
547 field associated with such pointers (as in a gss_buffer_desc
548 structure) should also be set to zero in such cases.
550 The GSS status code GSS_S_FAILURE is used to indicate that the
551 underlying mechanism detected an error for which no specific GSS
552 status code is defined. The mechanism status code will provide more
553 details about the error.
557 A name is used to identify a person or entity. GSSAPI authenticates
558 the relationship between a name and the entity claiming the name.
564 RFC 1509 GSSAPI - Overview and C bindings September 1993
567 Two distinct representations are defined for names:
569 (a) A printable form, for presentation to a user
571 (b) An internal form, for presentation at the API
573 The syntax of a printable name is defined by the GSSAPI
574 implementation, and may be dependent on local system configuration,
575 or on individual user preference. The internal form provides a
576 canonical representation of the name that is independent of
579 A given GSSAPI implementation may support names drawn from multiple
580 namespaces. In such an implementation, the internal form of the name
581 must include fields that identify the namespace from which the name
582 is drawn. The namespace from which a printable name is drawn is
583 specified by an accompanying object identifier.
585 Routines (gss_import_name and gss_display_name) are provided to
586 convert names between their printable representations and the
587 gss_name_t type. gss_import_name may support multiple syntaxes for
588 each supported namespace, allowing users the freedom to choose a
589 preferred name representation. gss_display_name should use an
590 implementation-chosen preferred syntax for each supported name-type.
592 Comparison of internal-form names is accomplished via the
593 gss_compare_names routine. This removes the need for the application
594 program to understand the syntaxes of the various printable names
595 that a given GSSAPI implementation may support.
597 Storage is allocated by routines that return gss_name_t values. A
598 procedure, gss_release_name, is provided to free storage associated
601 2.1.11. Channel Bindings
603 GSSAPI supports the use of user-specified tags to identify a given
604 context to the peer application. These tags are used to identify the
605 particular communications channel that carries the context. Channel
606 bindings are communicated to the GSSAPI using the following
620 RFC 1509 GSSAPI - Overview and C bindings September 1993
623 typedef struct gss_channel_bindings_struct {
624 OM_uint32 initiator_addrtype;
625 gss_buffer_desc initiator_address;
626 OM_uint32 acceptor_addrtype;
627 gss_buffer_desc acceptor_address;
628 gss_buffer_desc application_data;
629 } *gss_channel_bindings_t;
631 The initiator_addrtype and acceptor_addrtype fields denote the type
632 of addresses contained in the initiator_address and acceptor_address
633 buffers. The address type should be one of the following:
635 GSS_C_AF_UNSPEC Unspecified address type
636 GSS_C_AF_LOCAL Host-local address type
637 GSS_C_AF_INET DARPA Internet address type
638 GSS_C_AF_IMPLINK ARPAnet IMP address type (eg IP)
639 GSS_C_AF_PUP pup protocols (eg BSP) address type
640 GSS_C_AF_CHAOS MIT CHAOS protocol address type
641 GSS_C_AF_NS XEROX NS address type
642 GSS_C_AF_NBS nbs address type
643 GSS_C_AF_ECMA ECMA address type
644 GSS_C_AF_DATAKIT datakit protocols address type
645 GSS_C_AF_CCITT CCITT protocols (eg X.25)
646 GSS_C_AF_SNA IBM SNA address type
647 GSS_C_AF_DECnet DECnet address type
648 GSS_C_AF_DLI Direct data link interface address type
649 GSS_C_AF_LAT LAT address type
650 GSS_C_AF_HYLINK NSC Hyperchannel address type
651 GSS_C_AF_APPLETALK AppleTalk address type
652 GSS_C_AF_BSC BISYNC 2780/3780 address type
653 GSS_C_AF_DSS Distributed system services address type
654 GSS_C_AF_OSI OSI TP4 address type
656 GSS_C_AF_NULLADDR No address specified
658 Note that these name address families rather than specific addressing
659 formats. For address families that contain several alternative
660 address forms, the initiator_address and acceptor_address fields must
661 contain sufficient information to determine which address form is
662 used. When not otherwise specified, addresses should be specified in
665 Conceptually, the GSSAPI concatenates the initiator_addrtype,
666 initiator_address, acceptor_addrtype, acceptor_address and
667 application_data to form an octet string. The mechanism signs this
668 octet string, and binds the signature to the context establishment
669 token emitted by gss_init_sec_context. The same bindings are
670 presented by the context acceptor to gss_accept_sec_context, and a
676 RFC 1509 GSSAPI - Overview and C bindings September 1993
679 signature is calculated in the same way. The calculated signature is
680 compared with that found in the token, and if the signatures differ,
681 gss_accept_sec_context will return a GSS_S_BAD_BINDINGS error, and
682 the context will not be established. Some mechanisms may include the
683 actual channel binding data in the token (rather than just a
684 signature); applications should therefore not use confidential data
685 as channel-binding components. Individual mechanisms may impose
686 additional constraints on addresses and address types that may appear
687 in channel bindings. For example, a mechanism may verify that the
688 initiator_address field of the channel bindings presented to
689 gss_init_sec_context contains the correct network address of the host
692 2.1.12. Optional parameters
694 Various parameters are described as optional. This means that they
695 follow a convention whereby a default value may be requested. The
696 following conventions are used for omitted parameters. These
697 conventions apply only to those parameters that are explicitly
698 documented as optional.
700 2.1.12.1. gss_buffer_t types
702 Specify GSS_C_NO_BUFFER as a value. For an input parameter this
703 signifies that default behavior is requested, while for an output
704 parameter it indicates that the information that would be returned
705 via the parameter is not required by the application.
707 2.1.12.2. Integer types (input)
709 Individual parameter documentation lists values to be used to
710 indicate default actions.
712 2.1.12.3. Integer types (output)
714 Specify NULL as the value for the pointer.
716 2.1.12.4. Pointer types
718 Specify NULL as the value.
722 Specify GSS_C_NULL_OID as the value.
724 2.1.12.6. Object ID Sets
726 Specify GSS_C_NULL_OID_SET as the value.
732 RFC 1509 GSSAPI - Overview and C bindings September 1993
735 2.1.12.7. Credentials
737 Specify GSS_C_NO_CREDENTIAL to use the default credential handle.
739 2.1.12.8. Channel Bindings
741 Specify GSS_C_NO_CHANNEL_BINDINGS to indicate that channel bindings
744 3. GSSAPI routine descriptions
746 2.1. gss_acquire_cred
748 OM_uint32 gss_acquire_cred (
749 OM_uint32 * minor_status,
750 gss_name_t desired_name,
752 gss_OID_set desired_mechs,
754 gss_cred_id_t * output_cred_handle,
755 gss_OID_set * actual_mechs,
759 Allows an application to acquire a handle for a pre-existing
760 credential by name. GSSAPI implementations must impose a local
761 access-control policy on callers of this routine to prevent
762 unauthorized callers from acquiring credentials to which they are not
763 entitled. This routine is not intended to provide a "login to the
764 network" function, as such a function would result in the creation of
765 new credentials rather than merely acquiring a handle to existing
766 credentials. Such functions, if required, should be defined in
767 implementation-specific extensions to the API.
769 If credential acquisition is time-consuming for a mechanism, the
770 mechanism may chooses to delay the actual acquisition until the
771 credential is required (e.g., by gss_init_sec_context or
772 gss_accept_sec_context). Such mechanism-specific implementation
773 decisions should be invisible to the calling application; thus a call
774 of gss_inquire_cred immediately following the call of
775 gss_acquire_cred must return valid credential data, and may therefore
776 incur the overhead of a deferred credential acquisition.
780 desired_name gss_name_t, read
781 Name of principal whose credential
788 RFC 1509 GSSAPI - Overview and C bindings September 1993
791 time_req integer, read
792 number of seconds that credentials
795 desired_mechs Set of Object IDs, read
796 set of underlying security mechanisms that
797 may be used. GSS_C_NULL_OID_SET may be used
798 to obtain an implementation-specific default.
800 cred_usage integer, read
801 GSS_C_BOTH - Credentials may be used
802 either to initiate or accept
804 GSS_C_INITIATE - Credentials will only be
805 used to initiate security
807 GSS_C_ACCEPT - Credentials will only be used to
808 accept security contexts.
810 output_cred_handle gss_cred_id_t, modify
811 The returned credential handle.
813 actual_mechs Set of Object IDs, modify, optional
814 The set of mechanisms for which the
815 credential is valid. Specify NULL
818 time_rec Integer, modify, optional
819 Actual number of seconds for which the
820 returned credentials will remain valid. If the
821 implementation does not support expiration of
822 credentials, the value GSS_C_INDEFINITE will
823 be returned. Specify NULL if not required
825 minor_status Integer, modify
826 Mechanism specific status code.
831 GSS_S_COMPLETE Successful completion
833 GSS_S_BAD_MECH Unavailable mechanism requested
835 GSS_S_BAD_NAMETYPE Type contained within desired_name parameter is
838 GSS_S_BAD_NAME Value supplied for desired_name parameter is
844 RFC 1509 GSSAPI - Overview and C bindings September 1993
849 GSS_S_FAILURE Unspecified failure. The minor_status parameter
850 contains more detailed information
852 3.2. gss_release_cred
854 OM_uint32 gss_release_cred (
855 OM_uint32 * minor_status,
856 gss_cred_id_t * cred_handle)
860 Informs GSSAPI that the specified credential handle is no longer
861 required by the process. When all processes have released a
862 credential, it will be deleted.
866 cred_handle gss_cred_id_t, modify, optional
867 buffer containing opaque credential
868 handle. If GSS_C_NO_CREDENTIAL is supplied,
869 the default credential will be released
871 minor_status integer, modify
872 Mechanism specific status code.
878 GSS_S_COMPLETE Successful completion
880 GSS_S_NO_CRED Credentials could not be accessed.
900 RFC 1509 GSSAPI - Overview and C bindings September 1993
903 3.3. gss_init_sec_context
905 OM_uint32 gss_init_sec_context (
906 OM_uint32 * minor_status,
907 gss_cred_id_t claimant_cred_handle,
908 gss_ctx_id_t * context_handle,
909 gss_name_t target_name,
913 gss_channel_bindings_t
915 gss_buffer_t input_token
916 gss_OID * actual_mech_type,
917 gss_buffer_t output_token,
919 OM_uint32 * time_rec )
923 Initiates the establishment of a security context between the
924 application and a remote peer. Initially, the input_token parameter
925 should be specified as GSS_C_NO_BUFFER. The routine may return a
926 output_token which should be transferred to the peer application,
927 where the peer application will present it to gss_accept_sec_context.
928 If no token need be sent, gss_init_sec_context will indicate this by
929 setting the length field of the output_token argument to zero. To
930 complete the context establishment, one or more reply tokens may be
931 required from the peer application; if so, gss_init_sec_context will
932 return a status indicating GSS_S_CONTINUE_NEEDED in which case it
933 should be called again when the reply token is received from the peer
934 application, passing the token to gss_init_sec_context via the
935 input_token parameters.
937 The values returned via the ret_flags and time_rec parameters are not
938 defined unless the routine returns GSS_S_COMPLETE.
942 claimant_cred_handle gss_cred_id_t, read, optional
943 handle for credentials claimed. Supply
944 GSS_C_NO_CREDENTIAL to use default
947 context_handle gss_ctx_id_t, read/modify
948 context handle for new context. Supply
949 GSS_C_NO_CONTEXT for first call; use value
950 returned by first call in continuation calls.
956 RFC 1509 GSSAPI - Overview and C bindings September 1993
959 target_name gss_name_t, read
962 mech_type OID, read, optional
963 Object ID of desired mechanism. Supply
964 GSS_C_NULL_OID to obtain an implementation
967 req_flags bit-mask, read
968 Contains four independent flags, each of
969 which requests that the context support a
970 specific service option. Symbolic
971 names are provided for each flag, and the
972 symbolic names corresponding to the required
973 flags should be logically-ORed
974 together to form the bit-mask value. The
978 True - Delegate credentials to remote peer
979 False - Don't delegate
981 True - Request that remote peer
983 False - Authenticate self to remote peer
986 True - Enable replay detection for signed
988 False - Don't attempt to detect
991 True - Enable detection of out-of-sequence
992 signed or sealed messages
993 False - Don't attempt to detect
994 out-of-sequence messages
996 time_req integer, read
997 Desired number of seconds for which context
998 should remain valid. Supply 0 to request a
999 default validity period.
1001 input_chan_bindings channel bindings, read
1002 Application-specified bindings. Allows
1003 application to securely bind channel
1004 identification information to the security
1012 RFC 1509 GSSAPI - Overview and C bindings September 1993
1015 input_token buffer, opaque, read, optional (see text)
1016 Token received from peer application.
1017 Supply GSS_C_NO_BUFFER on initial call.
1019 actual_mech_type OID, modify
1020 actual mechanism used.
1022 output_token buffer, opaque, modify
1023 token to be sent to peer application. If
1024 the length field of the returned buffer is
1025 zero, no token need be sent to the peer
1028 ret_flags bit-mask, modify
1029 Contains six independent flags, each of which
1030 indicates that the context supports a specific
1031 service option. Symbolic names are provided
1032 for each flag, and the symbolic names
1033 corresponding to the required flags should be
1034 logically-ANDed with the ret_flags value to test
1035 whether a given option is supported by the
1036 context. The flags are:
1039 True - Credentials were delegated to
1041 False - No credentials were delegated
1043 True - Remote peer has been asked to
1044 authenticated itself
1045 False - Remote peer has not been asked to
1048 True - replay of signed or sealed messages
1050 False - replayed messages will not be
1053 True - out-of-sequence signed or sealed
1054 messages will be detected
1055 False - out-of-sequence messages will not
1058 True - Confidentiality service may be
1059 invoked by calling seal routine
1060 False - No confidentiality service (via
1061 seal) available. seal will provide
1062 message encapsulation, data-origin
1068 RFC 1509 GSSAPI - Overview and C bindings September 1993
1071 authentication and integrity
1074 True - Integrity service may be invoked by
1075 calling either gss_sign or gss_seal
1077 False - Per-message integrity service
1080 time_rec integer, modify, optional
1081 number of seconds for which the context
1082 will remain valid. If the implementation does
1083 not support credential expiration, the value
1084 GSS_C_INDEFINITE will be returned. Specify
1085 NULL if not required.
1087 minor_status integer, modify
1088 Mechanism specific status code.
1094 GSS_S_COMPLETE Successful completion
1096 GSS_S_CONTINUE_NEEDED Indicates that a token from the peer
1097 application is required to complete thecontext, and
1098 that gss_init_sec_context must be called again with
1101 GSS_S_DEFECTIVE_TOKEN Indicates that consistency checks performed on
1102 the input_token failed
1104 GSS_S_DEFECTIVE_CREDENTIAL Indicates that consistency checks
1105 performed on the credential failed.
1107 GSS_S_NO_CRED The supplied credentials were not valid for context
1108 initiation, or the credential handle did not
1109 reference any credentials.
1111 GSS_S_CREDENTIALS_EXPIRED The referenced credentials have expired
1113 GSS_S_BAD_BINDINGS The input_token contains different channel
1114 bindings to those specified via the
1115 input_chan_bindings parameter
1117 GSS_S_BAD_SIG The input_token contains an invalid signature, or a
1118 signature that could not be verified
1124 RFC 1509 GSSAPI - Overview and C bindings September 1993
1127 GSS_S_OLD_TOKEN The input_token was too old. This is a fatal error
1128 during context establishment
1130 GSS_S_DUPLICATE_TOKEN The input_token is valid, but is a duplicate of
1131 a token already processed. This is a fatal error
1132 during context establishment.
1134 GSS_S_NO_CONTEXT Indicates that the supplied context handle did not
1135 refer to a valid context
1137 GSS_S_BAD_NAMETYPE The provided target_name parameter contained an
1138 invalid or unsupported type of name
1140 GSS_S_BAD_NAME The provided target_name parameter was ill-formed.
1142 GSS_S_FAILURE Failure. See minor_status for more information
1144 3.4. gss_accept_sec_context
1146 OM_uint32 gss_accept_sec_context (
1147 OM_uint32 * minor_status,
1148 gss_ctx_id_t * context_handle,
1149 gss_cred_id_t verifier_cred_handle,
1150 gss_buffer_t input_token_buffer
1151 gss_channel_bindings_t
1152 input_chan_bindings,
1153 gss_name_t * src_name,
1154 gss_OID * mech_type,
1155 gss_buffer_t output_token,
1157 OM_uint32 * time_rec,
1158 gss_cred_id_t * delegated_cred_handle)
1162 Allows a remotely initiated security context between the application
1163 and a remote peer to be established. The routine may return a
1164 output_token which should be transferred to the peer application,
1165 where the peer application will present it to gss_init_sec_context.
1166 If no token need be sent, gss_accept_sec_context will indicate this
1167 by setting the length field of the output_token argument to zero. To
1168 complete the context establishment, one or more reply tokens may be
1169 required from the peer application; if so, gss_accept_sec_context
1170 will return a status flag of GSS_S_CONTINUE_NEEDED, in which case it
1171 should be called again when the reply token is received from the peer
1172 application, passing the token to gss_accept_sec_context via the
1173 input_token parameters.
1180 RFC 1509 GSSAPI - Overview and C bindings September 1993
1183 The values returned via the src_name, ret_flags, time_rec, and
1184 delegated_cred_handle parameters are not defined unless the routine
1185 returns GSS_S_COMPLETE.
1189 context_handle gss_ctx_id_t, read/modify
1190 context handle for new context. Supply
1191 GSS_C_NO_CONTEXT for first call; use value
1192 returned in subsequent calls.
1194 verifier_cred_handle gss_cred_id_t, read, optional
1195 Credential handle claimed by context
1197 Specify GSS_C_NO_CREDENTIAL to use default
1198 credentials. If GSS_C_NO_CREDENTIAL is
1199 specified, but the caller has no default
1200 credentials established, an
1201 implementation-defined default credential
1204 input_token_buffer buffer, opaque, read
1205 token obtained from remote application
1207 input_chan_bindings channel bindings, read
1208 Application-specified bindings. Allows
1209 application to securely bind channel
1210 identification information to the security
1213 src_name gss_name_t, modify, optional
1214 Authenticated name of context initiator.
1215 After use, this name should be deallocated by
1216 passing it to gss_release_name. If not required,
1219 mech_type Object ID, modify
1220 Security mechanism used. The returned
1221 OID value will be a pointer into static
1222 storage, and should be treated as read-only
1225 output_token buffer, opaque, modify
1226 Token to be passed to peer application. If the
1227 length field of the returned token buffer is 0,
1228 then no token need be passed to the peer
1236 RFC 1509 GSSAPI - Overview and C bindings September 1993
1239 ret_flags bit-mask, modify
1240 Contains six independent flags, each of
1241 which indicates that the context supports a
1242 specific service option. Symbolic names are
1243 provided for each flag, and the symbolic names
1244 corresponding to the required flags
1245 should be logically-ANDed with the ret_flags
1246 value to test whether a given option is
1247 supported by the context. The flags are:
1249 True - Delegated credentials are available
1250 via the delegated_cred_handle
1252 False - No credentials were delegated
1254 True - Remote peer asked for mutual
1256 False - Remote peer did not ask for mutual
1259 True - replay of signed or sealed messages
1261 False - replayed messages will not be
1264 True - out-of-sequence signed or sealed
1265 messages will be detected
1266 False - out-of-sequence messages will not
1269 True - Confidentiality service may be
1270 invoked by calling seal routine
1271 False - No confidentiality service (via
1272 seal) available. seal will
1273 provide message encapsulation,
1274 data-origin authentication and
1275 integrity services only.
1277 True - Integrity service may be invoked
1278 by calling either gss_sign or
1280 False - Per-message integrity service
1283 time_rec integer, modify, optional
1284 number of seconds for which the context
1285 will remain valid. Specify NULL if not required.
1292 RFC 1509 GSSAPI - Overview and C bindings September 1993
1295 delegated_cred_handle
1296 gss_cred_id_t, modify
1297 credential handle for credentials received from
1298 context initiator. Only valid if deleg_flag in
1301 minor_status integer, modify
1302 Mechanism specific status code.
1308 GSS_S_COMPLETE Successful completion
1310 GSS_S_CONTINUE_NEEDED Indicates that a token from the peer
1311 application is required to complete the context,
1312 and that gss_accept_sec_context must be called
1313 again with that token.
1315 GSS_S_DEFECTIVE_TOKEN Indicates that consistency checks
1316 performed on the input_token failed.
1318 GSS_S_DEFECTIVE_CREDENTIAL Indicates that consistency checks
1319 performed on the credential failed.
1321 GSS_S_NO_CRED The supplied credentials were not valid for
1322 context acceptance, or the credential handle
1323 did not reference any credentials.
1325 GSS_S_CREDENTIALS_EXPIRED The referenced credentials have
1328 GSS_S_BAD_BINDINGS The input_token contains different channel
1329 bindings to those specified via the
1330 input_chan_bindings parameter.
1332 GSS_S_NO_CONTEXT Indicates that the supplied context handle did
1333 not refer to a valid context.
1335 GSS_S_BAD_SIG The input_token contains an invalid signature.
1337 GSS_S_OLD_TOKEN The input_token was too old. This is a fatal
1338 error during context establishment.
1340 GSS_S_DUPLICATE_TOKEN The input_token is valid, but is a
1341 duplicate of a token already processed. This
1342 is a fatal error during context establishment.
1348 RFC 1509 GSSAPI - Overview and C bindings September 1993
1351 GSS_S_FAILURE Failure. See minor_status for more information.
1353 3.5. gss_process_context_token
1355 OM_uint32 gss_process_context_token (
1356 OM_uint32 * minor_status,
1357 gss_ctx_id_t context_handle,
1358 gss_buffer_t token_buffer)
1362 Provides a way to pass a token to the security service. Usually,
1363 tokens are associated either with context establishment (when they
1364 would be passed to gss_init_sec_context or gss_accept_sec_context) or
1365 with per-message security service (when they would be passed to
1366 gss_verify or gss_unseal). Occasionally, tokens may be received at
1367 other times, and gss_process_context_token allows such tokens to be
1368 passed to the underlying security service for processing. At
1369 present, such additional tokens may only be generated by
1370 gss_delete_sec_context. GSSAPI implementation may use this service
1371 to implement deletion of the security context.
1375 context_handle gss_ctx_id_t, read
1376 context handle of context on which token is to
1379 token_buffer buffer, opaque, read
1380 pointer to first byte of token to process
1382 minor_status integer, modify
1383 Implementation specific status code.
1389 GSS_S_COMPLETE Successful completion
1391 GSS_S_DEFECTIVE_TOKEN Indicates that consistency checks
1392 performed on the token failed
1394 GSS_S_FAILURE Failure. See minor_status for more information
1396 GSS_S_NO_CONTEXT The context_handle did not refer to a valid
1404 RFC 1509 GSSAPI - Overview and C bindings September 1993
1407 3.6. gss_delete_sec_context
1409 OM_uint32 gss_delete_sec_context (
1410 OM_uint32 * minor_status,
1411 gss_ctx_id_t * context_handle,
1412 gss_buffer_t output_token)
1416 Delete a security context. gss_delete_sec_context will delete the
1417 local data structures associated with the specified security context,
1418 and generate an output_token, which when passed to the peer
1419 gss_process_context_token will instruct it to do likewise. No
1420 further security services may be obtained using the context specified
1425 minor_status integer, modify
1426 Mechanism specific status code.
1428 context_handle gss_ctx_id_t, modify
1429 context handle identifying context to delete.
1431 output_token buffer, opaque, modify
1432 token to be sent to remote application to
1433 instruct it to also delete the context
1439 GSS_S_COMPLETE Successful completion
1441 GSS_S_FAILURE Failure, see minor_status for more information
1443 GSS_S_NO_CONTEXT No valid context was supplied
1445 3.7. gss_context_time
1447 OM_uint32 gss_context_time (
1448 OM_uint32 * minor_status,
1449 gss_ctx_id_t context_handle,
1450 OM_uint32 * time_rec)
1453 Determines the number of seconds for which the specified context will
1460 RFC 1509 GSSAPI - Overview and C bindings September 1993
1465 minor_status integer, modify
1466 Implementation specific status code.
1468 context_handle gss_ctx_id_t, read
1469 Identifies the context to be interrogated.
1471 time_rec integer, modify
1472 Number of seconds that the context will remain
1473 valid. If the context has already expired,
1474 zero will be returned.
1479 GSS_S_COMPLETE Successful completion
1481 GSS_S_CONTEXT_EXPIRED The context has already expired
1483 GSS_S_CREDENTIALS_EXPIRED The context is recognized, but
1484 associated credentials have expired
1486 GSS_S_NO_CONTEXT The context_handle parameter did not identify a
1491 OM_uint32 gss_sign (
1492 OM_uint32 * minor_status,
1493 gss_ctx_id_t context_handle,
1495 gss_buffer_t message_buffer,
1496 gss_buffer_t msg_token)
1499 Generates a cryptographic signature for the supplied message, and
1500 places the signature in a token for transfer to the peer application.
1501 The qop_req parameter allows a choice between several cryptographic
1502 algorithms, if supported by the chosen mechanism.
1506 minor_status integer, modify
1507 Implementation specific status code.
1509 context_handle gss_ctx_id_t, read
1510 identifies the context on which the message
1516 RFC 1509 GSSAPI - Overview and C bindings September 1993
1521 qop_req integer, read, optional
1522 Specifies requested quality of protection.
1523 Callers are encouraged, on portability grounds,
1524 to accept the default quality of protection
1525 offered by the chosen mechanism, which may be
1526 requested by specifying GSS_C_QOP_DEFAULT for
1527 this parameter. If an unsupported protection
1528 strength is requested, gss_sign will return a
1529 major_status of GSS_S_FAILURE.
1531 message_buffer buffer, opaque, read
1532 message to be signed
1534 msg_token buffer, opaque, modify
1535 buffer to receive token
1541 GSS_S_COMPLETE Successful completion
1543 GSS_S_CONTEXT_EXPIRED The context has already expired
1545 GSS_S_CREDENTIALS_EXPIRED The context is recognized, but
1546 associated credentials have expired
1548 GSS_S_NO_CONTEXT The context_handle parameter did not identify a
1551 GSS_S_FAILURE Failure. See minor_status for more information.
1555 OM_uint32 gss_verify (
1556 OM_uint32 * minor_status,
1557 gss_ctx_id_t context_handle,
1558 gss_buffer_t message_buffer,
1559 gss_buffer_t token_buffer,
1563 Verifies that a cryptographic signature, contained in the token
1564 parameter, fits the supplied message. The qop_state parameter allows
1565 a message recipient to determine the strength of protection that was
1566 applied to the message.
1572 RFC 1509 GSSAPI - Overview and C bindings September 1993
1577 minor_status integer, modify
1578 Mechanism specific status code.
1580 context_handle gss_ctx_id_t, read
1581 identifies the context on which the message
1584 message_buffer buffer, opaque, read
1585 message to be verified
1587 token_buffer buffer, opaque, read
1588 token associated with message
1590 qop_state integer, modify
1591 quality of protection gained from signature
1597 GSS_S_COMPLETE Successful completion
1599 GSS_S_DEFECTIVE_TOKEN The token failed consistency checks
1601 GSS_S_BAD_SIG The signature was incorrect
1603 GSS_S_DUPLICATE_TOKEN The token was valid, and contained a correct
1604 signature for the message, but it had already
1607 GSS_S_OLD_TOKEN The token was valid, and contained a correct
1608 signature for the message, but it is too old
1610 GSS_S_UNSEQ_TOKEN The token was valid, and contained a correct
1611 signature for the message, but has been
1612 verified out of sequence; an earlier token has
1613 been signed or sealed by the remote
1614 application, but not yet been processed
1617 GSS_S_CONTEXT_EXPIRED The context has already expired
1619 GSS_S_CREDENTIALS_EXPIRED The context is recognized, but
1620 associated credentials have expired
1628 RFC 1509 GSSAPI - Overview and C bindings September 1993
1631 GSS_S_NO_CONTEXT The context_handle parameter did not identify a
1634 GSS_S_FAILURE Failure. See minor_status for more information.
1638 OM_uint32 gss_seal (
1639 OM_uint32 * minor_status,
1640 gss_ctx_id_t context_handle,
1643 gss_buffer_t input_message_buffer,
1645 gss_buffer_t output_message_buffer)
1649 Cryptographically signs and optionally encrypts the specified
1650 input_message. The output_message contains both the signature and
1651 the message. The qop_req parameter allows a choice between several
1652 cryptographic algorithms, if supported by the chosen mechanism.
1656 minor_status integer, modify
1657 Mechanism specific status code.
1659 context_handle gss_ctx_id_t, read
1660 identifies the context on which the message
1663 conf_req_flag boolean, read
1664 True - Both confidentiality and integrity
1665 services are requested
1666 False - Only integrity service is requested
1668 qop_req integer, read, optional
1669 Specifies required quality of protection. A
1670 mechanism-specific default may be requested by
1671 setting qop_req to GSS_C_QOP_DEFAULT. If an
1672 unsupported protection strength is requested,
1673 gss_seal will return a major_status of
1676 input_message_buffer buffer, opaque, read
1677 message to be sealed
1684 RFC 1509 GSSAPI - Overview and C bindings September 1993
1687 conf_state boolean, modify
1688 True - Confidentiality, data origin
1689 authentication and integrity services
1691 False - Integrity and data origin services only
1694 output_message_buffer buffer, opaque, modify
1695 buffer to receive sealed message
1701 GSS_S_COMPLETE Successful completion
1703 GSS_S_CONTEXT_EXPIRED The context has already expired
1705 GSS_S_CREDENTIALS_EXPIRED The context is recognized, but
1706 associated credentials have expired
1708 GSS_S_NO_CONTEXT The context_handle parameter did not identify a
1711 GSS_S_FAILURE Failure. See minor_status for more information.
1715 OM_uint32 gss_unseal (
1716 OM_uint32 * minor_status,
1717 gss_ctx_id_t context_handle,
1718 gss_buffer_t input_message_buffer,
1719 gss_buffer_t output_message_buffer,
1725 Converts a previously sealed message back to a usable form, verifying
1726 the embedded signature. The conf_state parameter indicates whether
1727 the message was encrypted; the qop_state parameter indicates the
1728 strength of protection that was used to provide the confidentiality
1729 and integrity services.
1733 minor_status integer, modify
1734 Mechanism specific status code.
1740 RFC 1509 GSSAPI - Overview and C bindings September 1993
1743 context_handle gss_ctx_id_t, read
1744 identifies the context on which the message
1747 input_message_buffer buffer, opaque, read
1750 output_message_buffer buffer, opaque, modify
1751 buffer to receive unsealed message
1753 conf_state boolean, modify
1754 True - Confidentiality and integrity protection
1756 False - Inteegrity service only was used
1758 qop_state integer, modify
1759 quality of protection gained from signature
1765 GSS_S_COMPLETE Successful completion
1767 GSS_S_DEFECTIVE_TOKEN The token failed consistency checks
1769 GSS_S_BAD_SIG The signature was incorrect
1771 GSS_S_DUPLICATE_TOKEN The token was valid, and contained a
1772 correct signature for the message, but it had
1773 already been processed
1775 GSS_S_OLD_TOKEN The token was valid, and contained a correct
1776 signature for the message, but it is too old
1778 GSS_S_UNSEQ_TOKEN The token was valid, and contained a correct
1779 signature for the message, but has been
1780 verified out of sequence; an earlier token has
1781 been signed or sealed by the remote
1782 application, but not yet been processed
1785 GSS_S_CONTEXT_EXPIRED The context has already expired
1787 GSS_S_CREDENTIALS_EXPIRED The context is recognized, but
1788 associated credentials have expired
1796 RFC 1509 GSSAPI - Overview and C bindings September 1993
1799 GSS_S_NO_CONTEXT The context_handle parameter did not identify a
1802 GSS_S_FAILURE Failure. See minor_status for more information.
1804 3.12. gss_display_status
1806 OM_uint32 gss_display_status (
1807 OM_uint32 * minor_status,
1811 int * message_context,
1812 gss_buffer_t status_string)
1816 Allows an application to obtain a textual representation of a GSSAPI
1817 status code, for display to the user or for logging purposes. Since
1818 some status values may indicate multiple errors, applications may
1819 need to call gss_display_status multiple times, each call generating
1820 a single text string. The message_context parameter is used to
1821 indicate which error message should be extracted from a given
1822 status_value; message_context should be initialized to 0, and
1823 gss_display_status will return a non-zero value if there are further
1824 messages to extract.
1828 minor_status integer, modify
1829 Mechanism specific status code.
1831 status_value integer, read
1832 Status value to be converted
1834 status_type integer, read
1835 GSS_C_GSS_CODE - status_value is a GSS status
1837 GSS_C_MECH_CODE - status_value is a mechanism
1840 mech_type Object ID, read, optional
1841 Underlying mechanism (used to interpret a
1842 minor status value) Supply GSS_C_NULL_OID to
1843 obtain the system default.
1845 message_context integer, read/modify
1846 Should be initialized to zero by caller
1852 RFC 1509 GSSAPI - Overview and C bindings September 1993
1855 on first call. If further messages are
1856 contained in the status_value parameter,
1857 message_context will be non-zero on return,
1858 and this value should be passed back to
1859 subsequent calls, along with the same
1860 status_value, status_type and mech_type
1863 status_string buffer, character string, modify
1864 textual interpretation of the status_value
1870 GSS_S_COMPLETE Successful completion
1872 GSS_S_BAD_MECH Indicates that translation in accordance with
1873 an unsupported mechanism type was requested
1875 GSS_S_BAD_STATUS The status value was not recognized, or the
1876 status type was neither GSS_C_GSS_CODE nor
1880 3.13. gss_indicate_mechs
1882 OM_uint32 gss_indicate_mechs (
1883 OM_uint32 * minor_status,
1884 gss_OID_set * mech_set)
1888 Allows an application to determine which underlying security
1889 mechanisms are available.
1893 minor_status integer, modify
1894 Mechanism specific status code.
1896 mech_set set of Object IDs, modify
1897 set of implementation-supported mechanisms.
1898 The returned gss_OID_set value will be a
1899 pointer into static storage, and should be
1900 treated as read-only by the caller.
1908 RFC 1509 GSSAPI - Overview and C bindings September 1993
1915 GSS_S_COMPLETE Successful completion
1917 3.14. gss_compare_name
1919 OM_uint32 gss_compare_name (
1920 OM_uint32 * minor_status,
1927 Allows an application to compare two internal-form names to determine
1928 whether they refer to the same entity.
1932 minor_status integer, modify
1933 Mechanism specific status code.
1935 name1 gss_name_t, read
1938 name2 gss_name_t, read
1941 name_equal boolean, modify
1942 True - names refer to same entity
1943 False - names refer to different entities
1944 (strictly, the names are not known to
1945 refer to the same identity).
1950 GSS_S_COMPLETE Successful completion
1952 GSS_S_BAD_NAMETYPE The type contained within either name1 or
1953 name2 was unrecognized, or the names were of
1956 GSS_S_BAD_NAME One or both of name1 or name2 was ill-formed
1964 RFC 1509 GSSAPI - Overview and C bindings September 1993
1967 3.15. gss_display_name
1969 OM_uint32 gss_display_name (
1970 OM_uint32 * minor_status,
1971 gss_name_t input_name,
1972 gss_buffer_t output_name_buffer,
1973 gss_OID * output_name_type)
1977 Allows an application to obtain a textual representation of an opaque
1978 internal-form name for display purposes. The syntax of a printable
1979 name is defined by the GSSAPI implementation.
1983 minor_status integer, modify
1984 Mechanism specific status code.
1986 input_name gss_name_t, read
1987 name to be displayed
1989 output_name_buffer buffer, character-string, modify
1990 buffer to receive textual name string
1992 output_name_type Object ID, modify
1993 The type of the returned name. The returned
1994 gss_OID will be a pointer into static storage,
1995 and should be treated as read-only by the caller
2001 GSS_S_COMPLETE Successful completion
2003 GSS_S_BAD_NAMETYPE The type of input_name was not recognized
2005 GSS_S_BAD_NAME input_name was ill-formed
2007 3.16. gss_import_name
2009 OM_uint32 gss_import_name (
2010 OM_uint32 * minor_status,
2011 gss_buffer_t input_name_buffer,
2012 gss_OID input_name_type,
2013 gss_name_t * output_name)
2020 RFC 1509 GSSAPI - Overview and C bindings September 1993
2025 Convert a printable name to internal form.
2029 minor_status integer, modify
2030 Mechanism specific status code
2032 input_name_buffer buffer, character-string, read
2033 buffer containing printable name to convert
2035 input_name_type Object ID, read, optional
2036 Object Id specifying type of printable
2037 name. Applications may specify either
2038 GSS_C_NULL_OID to use a local system-specific
2039 printable syntax, or an OID registered by the
2040 GSSAPI implementation to name a particular
2043 output_name gss_name_t, modify
2044 returned name in internal form
2050 GSS_S_COMPLETE Successful completion
2052 GSS_S_BAD_NAMETYPE The input_name_type was unrecognized
2054 GSS_S_BAD_NAME The input_name parameter could not be
2055 interpreted as a name of the specified type
2057 3.17. gss_release_name
2059 OM_uint32 gss_release_name (
2060 OM_uint32 * minor_status,
2065 Free GSSAPI-allocated storage associated with an internal form name.
2069 minor_status integer, modify
2070 Mechanism specific status code
2076 RFC 1509 GSSAPI - Overview and C bindings September 1993
2079 name gss_name_t, modify
2080 The name to be deleted
2086 GSS_S_COMPLETE Successful completion
2088 GSS_S_BAD_NAME The name parameter did not contain a valid name
2090 3.18. gss_release_buffer
2092 OM_uint32 gss_release_buffer (
2093 OM_uint32 * minor_status,
2094 gss_buffer_t buffer)
2098 Free storage associated with a buffer format name. The storage must
2099 have been allocated by a GSSAPI routine. In addition to freeing the
2100 associated storage, the routine will zero the length field in the
2105 minor_status integer, modify
2106 Mechanism specific status code
2108 buffer buffer, modify
2109 The storage associated with the buffer will be
2110 deleted. The gss_buffer_desc object will not
2111 be freed, but its length field will be zeroed.
2117 GSS_S_COMPLETE Successful completion
2119 3.19. gss_release_oid_set
2121 OM_uint32 gss_release_oid_set (
2122 OM_uint32 * minor_status,
2132 RFC 1509 GSSAPI - Overview and C bindings September 1993
2135 Free storage associated with a gss_OID_set object. The storage must
2136 have been allocated by a GSSAPI routine.
2140 minor_status integer, modify
2141 Mechanism specific status code
2143 set Set of Object IDs, modify
2144 The storage associated with the gss_OID_set
2151 GSS_S_COMPLETE Successful completion
2153 3.20. gss_inquire_cred
2155 OM_uint32 gss_inquire_cred (
2156 OM_uint32 * minor_status,
2157 gss_cred_id_t cred_handle,
2159 OM_uint32 * lifetime,
2161 gss_OID_set * mechanisms )
2165 Obtains information about a credential. The caller must already have
2166 obtained a handle that refers to the credential.
2170 minor_status integer, modify
2171 Mechanism specific status code
2173 cred_handle gss_cred_id_t, read
2174 A handle that refers to the target credential.
2175 Specify GSS_C_NO_CREDENTIAL to inquire about
2176 the default credential.
2178 name gss_name_t, modify
2179 The name whose identity the credential asserts.
2180 Specify NULL if not required.
2182 lifetime Integer, modify
2188 RFC 1509 GSSAPI - Overview and C bindings September 1993
2191 The number of seconds for which the credential
2192 will remain valid. If the credential has
2193 expired, this parameter will be set to zero.
2194 If the implementation does not support
2195 credential expiration, the value
2196 GSS_C_INDEFINITE will be returned. Specify
2197 NULL if not required.
2199 cred_usage Integer, modify
2200 How the credential may be used. One of the
2205 Specify NULL if not required.
2207 mechanisms gss_OID_set, modify
2208 Set of mechanisms supported by the credential.
2209 Specify NULL if not required.
2215 GSS_S_COMPLETE Successful completion
2217 GSS_S_NO_CRED The referenced credentials could not be
2220 GSS_S_DEFECTIVE_CREDENTIAL The referenced credentials were
2223 GSS_S_CREDENTIALS_EXPIRED The referenced credentials have expired.
2224 If the lifetime parameter was not passed as
2225 NULL, it will be set to 0.
2232 * First, define the platform-dependent types.
2234 typedef <platform-specific> OM_uint32;
2235 typedef <platform-specific> gss_ctx_id_t;
2236 typedef <platform-specific> gss_cred_id_t;
2237 typedef <platform-specific> gss_name_t;
2244 RFC 1509 GSSAPI - Overview and C bindings September 1993
2248 * Note that a platform supporting the xom.h X/Open header file
2249 * may make use of that header for the definitions of OM_uint32
2250 * and the structure to which gss_OID_desc equates.
2253 typedef struct gss_OID_desc_struct {
2256 } gss_OID_desc, *gss_OID;
2258 typedef struct gss_OID_set_desc_struct {
2261 } gss_OID_set_desc, *gss_OID_set;
2263 typedef struct gss_buffer_desc_struct {
2266 } gss_buffer_desc, *gss_buffer_t;
2268 typedef struct gss_channel_bindings_struct {
2269 OM_uint32 initiator_addrtype;
2270 gss_buffer_desc initiator_address;
2271 OM_uint32 acceptor_addrtype;
2272 gss_buffer_desc acceptor_address;
2273 gss_buffer_desc application_data;
2274 } *gss_channel_bindings_t;
2278 * Six independent flags each of which indicates that a context
2279 * supports a specific service option.
2281 #define GSS_C_DELEG_FLAG 1
2282 #define GSS_C_MUTUAL_FLAG 2
2283 #define GSS_C_REPLAY_FLAG 4
2284 #define GSS_C_SEQUENCE_FLAG 8
2285 #define GSS_C_CONF_FLAG 16
2286 #define GSS_C_INTEG_FLAG 32
2290 * Credential usage options
2292 #define GSS_C_BOTH 0
2293 #define GSS_C_INITIATE 1
2294 #define GSS_C_ACCEPT 2
2300 RFC 1509 GSSAPI - Overview and C bindings September 1993
2304 * Status code types for gss_display_status
2306 #define GSS_C_GSS_CODE 1
2307 #define GSS_C_MECH_CODE 2
2310 * The constant definitions for channel-bindings address families
2312 #define GSS_C_AF_UNSPEC 0;
2313 #define GSS_C_AF_LOCAL 1;
2314 #define GSS_C_AF_INET 2;
2315 #define GSS_C_AF_IMPLINK 3;
2316 #define GSS_C_AF_PUP 4;
2317 #define GSS_C_AF_CHAOS 5;
2318 #define GSS_C_AF_NS 6;
2319 #define GSS_C_AF_NBS 7;
2320 #define GSS_C_AF_ECMA 8;
2321 #define GSS_C_AF_DATAKIT 9;
2322 #define GSS_C_AF_CCITT 10;
2323 #define GSS_C_AF_SNA 11;
2324 #define GSS_C_AF_DECnet 12;
2325 #define GSS_C_AF_DLI 13;
2326 #define GSS_C_AF_LAT 14;
2327 #define GSS_C_AF_HYLINK 15;
2328 #define GSS_C_AF_APPLETALK 16;
2329 #define GSS_C_AF_BSC 17;
2330 #define GSS_C_AF_DSS 18;
2331 #define GSS_C_AF_OSI 19;
2332 #define GSS_C_AF_X25 21;
2334 #define GSS_C_AF_NULLADDR 255;
2336 #define GSS_C_NO_BUFFER ((gss_buffer_t) 0)
2337 #define GSS_C_NULL_OID ((gss_OID) 0)
2338 #define GSS_C_NULL_OID_SET ((gss_OID_set) 0)
2339 #define GSS_C_NO_CONTEXT ((gss_ctx_id_t) 0)
2340 #define GSS_C_NO_CREDENTIAL ((gss_cred_id_t) 0)
2341 #define GSS_C_NO_CHANNEL_BINDINGS ((gss_channel_bindings_t) 0)
2342 #define GSS_C_EMPTY_BUFFER {0, NULL}
2345 * Define the default Quality of Protection for per-message
2346 * services. Note that an implementation that offers multiple
2347 * levels of QOP may either reserve a value (for example zero,
2348 * as assumed here) to mean "default protection", or alternatively
2349 * may simply equate GSS_C_QOP_DEFAULT to a specific explicit QOP
2356 RFC 1509 GSSAPI - Overview and C bindings September 1993
2360 #define GSS_C_QOP_DEFAULT 0
2363 * Expiration time of 2^32-1 seconds means infinite lifetime for a
2364 * credential or security context
2366 #define GSS_C_INDEFINITE 0xfffffffful
2369 /* Major status codes */
2371 #define GSS_S_COMPLETE 0
2374 * Some "helper" definitions to make the status code macros obvious.
2376 #define GSS_C_CALLING_ERROR_OFFSET 24
2377 #define GSS_C_ROUTINE_ERROR_OFFSET 16
2378 #define GSS_C_SUPPLEMENTARY_OFFSET 0
2379 #define GSS_C_CALLING_ERROR_MASK 0377ul
2380 #define GSS_C_ROUTINE_ERROR_MASK 0377ul
2381 #define GSS_C_SUPPLEMENTARY_MASK 0177777ul
2384 * The macros that test status codes for error conditions
2386 #define GSS_CALLING_ERROR(x) \
2387 (x & (GSS_C_CALLING_ERROR_MASK << GSS_C_CALLING_ERROR_OFFSET))
2388 #define GSS_ROUTINE_ERROR(x) \
2389 (x & (GSS_C_ROUTINE_ERROR_MASK << GSS_C_ROUTINE_ERROR_OFFSET))
2390 #define GSS_SUPPLEMENTARY_INFO(x) \
2391 (x & (GSS_C_SUPPLEMENTARY_MASK << GSS_C_SUPPLEMENTARY_OFFSET))
2392 #define GSS_ERROR(x) \
2393 ((GSS_CALLING_ERROR(x) != 0) || (GSS_ROUTINE_ERROR(x) != 0))
2397 * Now the actual status code definitions
2403 #define GSS_S_CALL_INACCESSIBLE_READ \
2404 (1ul << GSS_C_CALLING_ERROR_OFFSET)
2405 #define GSS_S_CALL_INACCESSIBLE_WRITE \
2406 (2ul << GSS_C_CALLING_ERROR_OFFSET)
2412 RFC 1509 GSSAPI - Overview and C bindings September 1993
2415 #define GSS_S_CALL_BAD_STRUCTURE \
2416 (3ul << GSS_C_CALLING_ERROR_OFFSET)
2421 #define GSS_S_BAD_MECH (1ul << GSS_C_ROUTINE_ERROR_OFFSET)
2422 #define GSS_S_BAD_NAME (2ul << GSS_C_ROUTINE_ERROR_OFFSET)
2423 #define GSS_S_BAD_NAMETYPE (3ul << GSS_C_ROUTINE_ERROR_OFFSET)
2424 #define GSS_S_BAD_BINDINGS (4ul << GSS_C_ROUTINE_ERROR_OFFSET)
2425 #define GSS_S_BAD_STATUS (5ul << GSS_C_ROUTINE_ERROR_OFFSET)
2426 #define GSS_S_BAD_SIG (6ul << GSS_C_ROUTINE_ERROR_OFFSET)
2427 #define GSS_S_NO_CRED (7ul << GSS_C_ROUTINE_ERROR_OFFSET)
2428 #define GSS_S_NO_CONTEXT (8ul << GSS_C_ROUTINE_ERROR_OFFSET)
2429 #define GSS_S_DEFECTIVE_TOKEN (9ul << GSS_C_ROUTINE_ERROR_OFFSET)
2430 #define GSS_S_DEFECTIVE_CREDENTIAL (10ul << GSS_C_ROUTINE_ERROR_OFFSET)
2431 #define GSS_S_CREDENTIALS_EXPIRED (11ul << GSS_C_ROUTINE_ERROR_OFFSET)
2432 #define GSS_S_CONTEXT_EXPIRED (12ul << GSS_C_ROUTINE_ERROR_OFFSET)
2433 #define GSS_S_FAILURE (13ul << GSS_C_ROUTINE_ERROR_OFFSET)
2436 * Supplementary info bits:
2438 #define GSS_S_CONTINUE_NEEDED (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 0))
2439 #define GSS_S_DUPLICATE_TOKEN (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 1))
2440 #define GSS_S_OLD_TOKEN (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 2))
2441 #define GSS_S_UNSEQ_TOKEN (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 3))
2445 * Finally, function prototypes for the GSSAPI routines.
2448 OM_uint32 gss_acquire_cred
2449 (OM_uint32*, /* minor_status */
2450 gss_name_t, /* desired_name */
2451 OM_uint32, /* time_req */
2452 gss_OID_set, /* desired_mechs */
2453 int, /* cred_usage */
2454 gss_cred_id_t*, /* output_cred_handle */
2455 gss_OID_set*, /* actual_mechs */
2456 OM_uint32* /* time_rec */
2459 OM_uint32 gss_release_cred,
2460 (OM_uint32*, /* minor_status */
2461 gss_cred_id_t* /* cred_handle */
2468 RFC 1509 GSSAPI - Overview and C bindings September 1993
2471 OM_uint32 gss_init_sec_context
2472 (OM_uint32*, /* minor_status */
2473 gss_cred_id_t, /* claimant_cred_handle */
2474 gss_ctx_id_t*, /* context_handle */
2475 gss_name_t, /* target_name */
2476 gss_OID, /* mech_type */
2477 int, /* req_flags */
2478 OM_uint32, /* time_req */
2479 gss_channel_bindings_t,
2480 /* input_chan_bindings */
2481 gss_buffer_t, /* input_token */
2482 gss_OID*, /* actual_mech_type */
2483 gss_buffer_t, /* output_token */
2484 int*, /* ret_flags */
2485 OM_uint32* /* time_rec */
2488 OM_uint32 gss_accept_sec_context
2489 (OM_uint32*, /* minor_status */
2490 gss_ctx_id_t*, /* context_handle */
2491 gss_cred_id_t, /* verifier_cred_handle */
2492 gss_buffer_t, /* input_token_buffer */
2493 gss_channel_bindings_t,
2494 /* input_chan_bindings */
2495 gss_name_t*, /* src_name */
2496 gss_OID*, /* mech_type */
2497 gss_buffer_t, /* output_token */
2498 int*, /* ret_flags */
2499 OM_uint32*, /* time_rec */
2500 gss_cred_id_t* /* delegated_cred_handle */
2503 OM_uint32 gss_process_context_token
2504 (OM_uint32*, /* minor_status */
2505 gss_ctx_id_t, /* context_handle */
2506 gss_buffer_t /* token_buffer */
2509 OM_uint32 gss_delete_sec_context
2510 (OM_uint32*, /* minor_status */
2511 gss_ctx_id_t*, /* context_handle */
2512 gss_buffer_t /* output_token */
2524 RFC 1509 GSSAPI - Overview and C bindings September 1993
2527 OM_uint32 gss_context_time
2528 (OM_uint32*, /* minor_status */
2529 gss_ctx_id_t, /* context_handle */
2530 OM_uint32* /* time_rec */
2534 (OM_uint32*, /* minor_status */
2535 gss_ctx_id_t, /* context_handle */
2537 gss_buffer_t, /* message_buffer */
2538 gss_buffer_t /* message_token */
2541 OM_uitn32 gss_verify
2542 (OM_uint32*, /* minor_status */
2543 gss_ctx_id_t, /* context_handle */
2544 gss_buffer_t, /* message_buffer */
2545 gss_buffer_t, /* token_buffer */
2546 int* /* qop_state */
2550 (OM_uint32*, /* minor_status */
2551 gss_ctx_id_t, /* context_handle */
2552 int, /* conf_req_flag */
2554 gss_buffer_t, /* input_message_buffer */
2555 int*, /* conf_state */
2556 gss_buffer_t /* output_message_buffer */
2559 OM_uint32 gss_unseal
2560 (OM_uint32*, /* minor_status */
2561 gss_ctx_id_t, /* context_handle */
2562 gss_buffer_t, /* input_message_buffer */
2563 gss_buffer_t, /* output_message_buffer */
2564 int*, /* conf_state */
2565 int* /* qop_state */
2580 RFC 1509 GSSAPI - Overview and C bindings September 1993
2583 OM_uint32 gss_display_status
2584 (OM_uint32*, /* minor_status */
2585 OM_uint32, /* status_value */
2586 int, /* status_type */
2587 gss_OID, /* mech_type */
2588 int*, /* message_context */
2589 gss_buffer_t /* status_string */
2592 OM_uint32 gss_indicate_mechs
2593 (OM_uint32*, /* minor_status */
2594 gss_OID_set* /* mech_set */
2597 OM_uint32 gss_compare_name
2598 (OM_uint32*, /* minor_status */
2599 gss_name_t, /* name1 */
2600 gss_name_t, /* name2 */
2601 int* /* name_equal */
2604 OM_uint32 gss_display_name,
2605 (OM_uint32*, /* minor_status */
2606 gss_name_t, /* input_name */
2607 gss_buffer_t, /* output_name_buffer */
2608 gss_OID* /* output_name_type */
2611 OM_uint32 gss_import_name
2612 (OM_uint32*, /* minor_status */
2613 gss_buffer_t, /* input_name_buffer */
2614 gss_OID, /* input_name_type */
2615 gss_name_t* /* output_name */
2618 OM_uint32 gss_release_name
2619 (OM_uint32*, /* minor_status */
2620 gss_name_t* /* input_name */
2623 OM_uint32 gss_release_buffer
2624 (OM_uint32*, /* minor_status */
2625 gss_buffer_t /* buffer */
2628 OM_uint32 gss_release_oid_set
2629 (OM_uint32*, /* minor_status */
2630 gss_OID_set* /* set */
2636 RFC 1509 GSSAPI - Overview and C bindings September 1993
2641 OM_uint32 gss_inquire_cred
2642 (OM_uint32 *, /* minor_status */
2643 gss_cred_id_t, /* cred_handle */
2644 gss_name_t *, /* name */
2645 OM_uint32 *, /* lifetime */
2646 int *, /* cred_usage */
2647 gss_OID_set * /* mechanisms */
2652 #endif /* GSSAPI_H_ */
2656 [1] Linn, J., "Generic Security Service Application Program
2657 Interface", RFC 1508, Geer Zolot Associate, September 1993.
2659 [2] "OSI Object Management API Specification, Version 2.0 t", X.400
2660 API Association & X/Open Company Limited, August 24, 1990.
2661 Specification of datatypes and routines for manipulating
2662 information objects.
2664 Security Considerations
2666 Security issues are discussed throughout this memo.
2671 Digital Equipment Corporation
2672 550 King Street, LKG2-2/AA6
2676 Phone: +1-508-486-5210
2677 EMail: Wray@tuxedo.enet.dec.com