NAME

gss_verify_mic, gss_verify — Check a MIC against a message; verify integrity of a received message

SYNOPSIS

#include <gssapi/gssapi.h>

OM_uint32
gss_verify_mic(OM_uint32 *minor_status, const gss_ctx_id_t context_handle, const gss_buffer_t message_buffer, const gss_buffer_t token_buffer, gss_qop_t *qop_state);

OM_uint32
gss_verify(OM_uint32 *minor_status, gss_ctx_id_t context_handle, gss_buffer_t message_buffer, gss_buffer_t token_buffer, gss_qop_t *qop_state);

DESCRIPTION

Verifies that a cryptographic MIC, contained in the token parameter, fits the supplied message. The qop_state parameter allows a message recipient to determine the strength of protection that was applied to the message.

Since some application-level protocols may wish to use tokens emitted by gss_wrap() to provide "secure framing", implementations must support the calculation and verification of MICs over zero-length messages.

The gss_verify() routine is an obsolete variant of gss_verify_mic(). It is provided for backwards compatibility with applications using the GSS-API V1 interface. A distinct entrypoint (as opposed to #define) is provided, both to allow GSS-API V1 applications to link and to retain the slight parameter type differences between the obsolete versions of this routine and its current form.

PARAMETERS

minor_status: Mechanism specific status code.
context_handle: Identifies the context on which the message arrived.
message_buffer: Message to be verified.
token_buffer: Token associated with message.
qop_state: Quality of protection gained from MIC. Specify NULL if not required.

RETURN VALUES

GSS_S_COMPLETE: Successful completion
GSS_S_DEFECTIVE_TOKEN: The token failed consistency checks
GSS_S_BAD_SIG: The MIC was incorrect
GSS_S_DUPLICATE_TOKEN: The token was valid, and contained a correct MIC for the message, but it had already been processed
GSS_S_OLD_TOKEN: The token was valid, and contained a correct MIC for the message, but it is too old to check for duplication
GSS_S_UNSEQ_TOKEN: The token was valid, and contained a correct MIC for the message, but has been verified out of sequence; a later token has already been received.
GSS_S_GAP_TOKEN: The token was valid, and contained a correct MIC for the message, but has been verified out of sequence; an earlier expected token has not yet been received
GSS_S_CONTEXT_EXPIRED: The context has already expired
GSS_S_NO_CONTEXT: The context_handle parameter did not identify a valid context

STANDARDS

RFC 2743: Generic Security Service Application Program Interface Version 2, Update 1
RFC 2744: Generic Security Service API Version 2 : C-bindings

HISTORY

The gss_verify_mic function first appeared in FreeBSD 7.0.

AUTHORS

John Wray, Iris Associates

COPYRIGHT

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