mirror of
https://github.com/isc-projects/bind9.git
synced 2026-05-28 04:34:54 -04:00
9bdace3fa3
Reject multi-round GSS-API negotiation (GSS_S_CONTINUE_NEEDED) in dst_gssapi_acceptctx(). Each call to gss_accept_sec_context() allocates a context inside the GSS library; without this fix, the context handle was passed back to process_gsstkey() which did not store it persistently, leaking it on every incomplete negotiation. An unauthenticated attacker could exhaust server memory by sending repeated TKEY queries with GSSAPI tokens, each leaking one GSS context. The leaked memory is allocated by the GSS library via malloc(), bypassing BIND's memory accounting. In practice, Kerberos/SPNEGO (the only mechanism used with BIND) completes in a single round, so rejecting continuation does not affect real-world deployments. See RFC 3645 Section 4.1.3. (cherry picked from commit 3d8e0d068f08694282c5ecd3bd6c332de6c75485)
189 lines
5.2 KiB
C
189 lines
5.2 KiB
C
/*
|
|
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
|
|
*
|
|
* SPDX-License-Identifier: MPL-2.0
|
|
*
|
|
* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
|
|
*
|
|
* See the COPYRIGHT file distributed with this work for additional
|
|
* information regarding copyright ownership.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
/*! \file dst/gssapi.h */
|
|
|
|
#include <inttypes.h>
|
|
#include <stdbool.h>
|
|
|
|
#include <isc/formatcheck.h>
|
|
#include <isc/lang.h>
|
|
#include <isc/types.h>
|
|
|
|
#include <dns/types.h>
|
|
|
|
typedef void *dns_gss_cred_id_t;
|
|
typedef void *dns_gss_ctx_id_t;
|
|
|
|
ISC_LANG_BEGINDECLS
|
|
|
|
/***
|
|
*** Types
|
|
***/
|
|
|
|
/***
|
|
*** Functions
|
|
***/
|
|
|
|
isc_result_t
|
|
dst_gssapi_acquirecred(const dns_name_t *name, bool initiate,
|
|
dns_gss_cred_id_t *cred);
|
|
/*
|
|
* Acquires GSS credentials.
|
|
*
|
|
* Requires:
|
|
* 'name' is a valid name, preferably one known by the GSS provider
|
|
* 'initiate' indicates whether the credentials are for initiating or
|
|
* accepting contexts
|
|
* 'cred' is a pointer to NULL, which will be allocated with the
|
|
* credential handle. Call dst_gssapi_releasecred to free
|
|
* the memory.
|
|
*
|
|
* Returns:
|
|
* ISC_R_SUCCESS msg was successfully updated to include the
|
|
* query to be sent
|
|
* other an error occurred while building the message
|
|
*/
|
|
|
|
isc_result_t
|
|
dst_gssapi_releasecred(dns_gss_cred_id_t *cred);
|
|
/*
|
|
* Releases GSS credentials. Calling this function does release the
|
|
* memory allocated for the credential in dst_gssapi_acquirecred()
|
|
*
|
|
* Requires:
|
|
* 'mctx' is a valid memory context
|
|
* 'cred' is a pointer to the credential to be released
|
|
*
|
|
* Returns:
|
|
* ISC_R_SUCCESS credential was released successfully
|
|
* other an error occurred while releaseing
|
|
* the credential
|
|
*/
|
|
|
|
isc_result_t
|
|
dst_gssapi_initctx(const dns_name_t *name, isc_buffer_t *intoken,
|
|
isc_buffer_t *outtoken, dns_gss_ctx_id_t *gssctx,
|
|
isc_mem_t *mctx, char **err_message);
|
|
/*
|
|
* Initiates a GSS context.
|
|
*
|
|
* Requires:
|
|
* 'name' is a valid name, preferably one known by the GSS
|
|
* provider
|
|
* 'intoken' is a token received from the acceptor, or NULL if
|
|
* there isn't one
|
|
* 'outtoken' is a buffer to receive the token generated by
|
|
* gss_init_sec_context() to be sent to the acceptor
|
|
* 'context' is a pointer to a valid dns_gss_ctx_id_t
|
|
* (which may have the value DNS_GSS_C_NO_CONTEXT)
|
|
*
|
|
* Returns:
|
|
* ISC_R_SUCCESS msg was successfully updated to include the
|
|
* query to be sent
|
|
* other an error occurred while building the message
|
|
* *err_message optional error message
|
|
*/
|
|
|
|
isc_result_t
|
|
dst_gssapi_acceptctx(dns_gss_cred_id_t cred, const char *gssapi_keytab,
|
|
isc_region_t *intoken, isc_buffer_t **outtoken,
|
|
dns_gss_ctx_id_t *context, dns_name_t *principal,
|
|
isc_mem_t *mctx);
|
|
/*
|
|
* Accepts a GSS context.
|
|
*
|
|
* Requires:
|
|
* 'mctx' is a valid memory context
|
|
* 'cred' is the acceptor's valid GSS credential handle
|
|
* 'intoken' is a token received from the initiator
|
|
* 'outtoken' is a pointer a buffer pointer used to return the token
|
|
* generated by gss_accept_sec_context() to be sent to the
|
|
* initiator
|
|
* 'context' is a valid pointer to receive the generated context handle.
|
|
*
|
|
* Requires:
|
|
* 'outtoken' != NULL && *outtoken == NULL.
|
|
* 'context' != NULL && *context == NULL.
|
|
*
|
|
* Returns:
|
|
* ISC_R_SUCCESS msg was successfully updated to include
|
|
* the query to be sent
|
|
* DNS_R_INVALIDTKEY an error occurred while accepting the
|
|
* context
|
|
* ISC_R_FAILURE other error occurred
|
|
*/
|
|
|
|
isc_result_t
|
|
dst_gssapi_deletectx(isc_mem_t *mctx, dns_gss_ctx_id_t *gssctx);
|
|
/*
|
|
* Destroys a GSS context. This function deletes the context from the GSS
|
|
* provider and then frees the memory used by the context pointer.
|
|
*
|
|
* Requires:
|
|
* 'mctx' is a valid memory context
|
|
* 'context' is a valid GSS context
|
|
*
|
|
* Returns:
|
|
* ISC_R_SUCCESS
|
|
*/
|
|
|
|
void
|
|
gss_log(int level, const char *fmt, ...) ISC_FORMAT_PRINTF(2, 3);
|
|
/*
|
|
* Logging function for GSS.
|
|
*
|
|
* Requires
|
|
* 'level' is the log level to be used, as an integer
|
|
* 'fmt' is a printf format specifier
|
|
*/
|
|
|
|
char *
|
|
gss_error_tostring(uint32_t major, uint32_t minor, char *buf, size_t buflen);
|
|
/*
|
|
* Render a GSS major status/minor status pair into a string
|
|
*
|
|
* Requires:
|
|
* 'major' is a GSS major status code
|
|
* 'minor' is a GSS minor status code
|
|
*
|
|
* Returns:
|
|
* A string containing the text representation of the error codes.
|
|
* Users should copy the string if they wish to keep it.
|
|
*/
|
|
|
|
bool
|
|
dst_gssapi_identitymatchesrealmkrb5(const dns_name_t *signer,
|
|
const dns_name_t *name,
|
|
const dns_name_t *realm, bool subdomain);
|
|
/*
|
|
* Compare a "signer" (in the format of a Kerberos-format Kerberos5
|
|
* principal: host/example.com@EXAMPLE.COM) to the realm name stored
|
|
* in "name" (which represents the realm name).
|
|
*
|
|
*/
|
|
|
|
bool
|
|
dst_gssapi_identitymatchesrealmms(const dns_name_t *signer,
|
|
const dns_name_t *name,
|
|
const dns_name_t *realm, bool subdomain);
|
|
/*
|
|
* Compare a "signer" (in the format of a Kerberos-format Kerberos5
|
|
* principal: host/example.com@EXAMPLE.COM) to the realm name stored
|
|
* in "name" (which represents the realm name).
|
|
*
|
|
*/
|
|
|
|
ISC_LANG_ENDDECLS
|