include/linux/sunrpc/gss_krb5.h - third_party/kernel - Git at Google

 /*
  *  linux/include/linux/sunrpc/gss_krb5_types.h
  *
  *  Adapted from MIT Kerberos 5-1.2.1 lib/include/krb5.h,
  *  lib/gssapi/krb5/gssapiP_krb5.h, and others
  *
  *  Copyright (c) 2000-2008 The Regents of the University of Michigan.
  *  All rights reserved.
  *
  *  Andy Adamson   <andros@umich.edu>
  *  Bruce Fields   <bfields@umich.edu>
  */

 /*
  * Copyright 1995 by the Massachusetts Institute of Technology.
  * All Rights Reserved.
  *
  * Export of this software from the United States of America may
  *   require a specific license from the United States Government.
  *   It is the responsibility of any person or organization contemplating
  *   export to obtain such a license before exporting.
  *
  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
  * distribute this software and its documentation for any purpose and
  * without fee is hereby granted, provided that the above copyright
  * notice appear in all copies and that both that copyright notice and
  * this permission notice appear in supporting documentation, and that
  * the name of M.I.T. not be used in advertising or publicity pertaining
  * to distribution of the software without specific, written prior
  * permission.  Furthermore if you modify this software you must label
  * your software as modified software and not distribute it in such a
  * fashion that it might be confused with the original M.I.T. software.
  * M.I.T. makes no representations about the suitability of
  * this software for any purpose.  It is provided "as is" without express
  * or implied warranty.
  *
  */

 #include <crypto/skcipher.h>
 #include <linux/sunrpc/auth_gss.h>
 #include <linux/sunrpc/gss_err.h>
 #include <linux/sunrpc/gss_asn1.h>

 /* Length of constant used in key derivation */
 #define GSS_KRB5_K5CLENGTH (5)

 /* Maximum key length (in bytes) for the supported crypto algorithms*/
 #define GSS_KRB5_MAX_KEYLEN (32)

 /* Maximum checksum function output for the supported crypto algorithms */
 #define GSS_KRB5_MAX_CKSUM_LEN  (20)

 /* Maximum blocksize for the supported crypto algorithms */
 #define GSS_KRB5_MAX_BLOCKSIZE  (16)

 struct krb5_ctx;

 struct gss_krb5_enctype {
 	const u32		etype;		/* encryption (key) type */
 	const u32		ctype;		/* checksum type */
 	const char		*name;		/* "friendly" name */
 	const char		*encrypt_name;	/* crypto encrypt name */
 	const char		*cksum_name;	/* crypto checksum name */
 	const u16		signalg;	/* signing algorithm */
 	const u16		sealalg;	/* sealing algorithm */
 	const u32		blocksize;	/* encryption blocksize */
 	const u32		conflen;	/* confounder length
 						   (normally the same as
 						   the blocksize) */
 	const u32		cksumlength;	/* checksum length */
 	const u32		keyed_cksum;	/* is it a keyed cksum? */
 	const u32		keybytes;	/* raw key len, in bytes */
 	const u32		keylength;	/* final key len, in bytes */
 	u32 (*encrypt) (struct crypto_sync_skcipher *tfm,
 			void *iv, void *in, void *out,
 			int length);		/* encryption function */
 	u32 (*decrypt) (struct crypto_sync_skcipher *tfm,
 			void *iv, void *in, void *out,
 			int length);		/* decryption function */
 	u32 (*mk_key) (const struct gss_krb5_enctype *gk5e,
 		       struct xdr_netobj *in,
 		       struct xdr_netobj *out);	/* complete key generation */
 	u32 (*encrypt_v2) (struct krb5_ctx *kctx, u32 offset,
 			   struct xdr_buf *buf,
 			   struct page **pages); /* v2 encryption function */
 	u32 (*decrypt_v2) (struct krb5_ctx *kctx, u32 offset, u32 len,
 			   struct xdr_buf *buf, u32 *headskip,
 			   u32 *tailskip);	/* v2 decryption function */
 };

 /* krb5_ctx flags definitions */
 #define KRB5_CTX_FLAG_INITIATOR         0x00000001
 #define KRB5_CTX_FLAG_CFX               0x00000002
 #define KRB5_CTX_FLAG_ACCEPTOR_SUBKEY   0x00000004

 struct krb5_ctx {
 	int			initiate; /* 1 = initiating, 0 = accepting */
 	u32			enctype;
 	u32			flags;
 	const struct gss_krb5_enctype *gk5e; /* enctype-specific info */
 	struct crypto_sync_skcipher *enc;
 	struct crypto_sync_skcipher *seq;
 	struct crypto_sync_skcipher *acceptor_enc;
 	struct crypto_sync_skcipher *initiator_enc;
 	struct crypto_sync_skcipher *acceptor_enc_aux;
 	struct crypto_sync_skcipher *initiator_enc_aux;
 	u8			Ksess[GSS_KRB5_MAX_KEYLEN]; /* session key */
 	u8			cksum[GSS_KRB5_MAX_KEYLEN];
 	atomic_t		seq_send;
 	atomic64_t		seq_send64;
 	time64_t		endtime;
 	struct xdr_netobj	mech_used;
 	u8			initiator_sign[GSS_KRB5_MAX_KEYLEN];
 	u8			acceptor_sign[GSS_KRB5_MAX_KEYLEN];
 	u8			initiator_seal[GSS_KRB5_MAX_KEYLEN];
 	u8			acceptor_seal[GSS_KRB5_MAX_KEYLEN];
 	u8			initiator_integ[GSS_KRB5_MAX_KEYLEN];
 	u8			acceptor_integ[GSS_KRB5_MAX_KEYLEN];
 };

 /* The length of the Kerberos GSS token header */
 #define GSS_KRB5_TOK_HDR_LEN	(16)

 #define KG_TOK_MIC_MSG    0x0101
 #define KG_TOK_WRAP_MSG   0x0201

 #define KG2_TOK_INITIAL     0x0101
 #define KG2_TOK_RESPONSE    0x0202
 #define KG2_TOK_MIC         0x0404
 #define KG2_TOK_WRAP        0x0504

 #define KG2_TOKEN_FLAG_SENTBYACCEPTOR   0x01
 #define KG2_TOKEN_FLAG_SEALED           0x02
 #define KG2_TOKEN_FLAG_ACCEPTORSUBKEY   0x04

 #define KG2_RESP_FLAG_ERROR             0x0001
 #define KG2_RESP_FLAG_DELEG_OK          0x0002

 enum sgn_alg {
 	SGN_ALG_DES_MAC_MD5 = 0x0000,
 	SGN_ALG_MD2_5 = 0x0001,
 	SGN_ALG_DES_MAC = 0x0002,
 	SGN_ALG_3 = 0x0003,		/* not published */
 	SGN_ALG_HMAC_SHA1_DES3_KD = 0x0004
 };
 enum seal_alg {
 	SEAL_ALG_NONE = 0xffff,
 	SEAL_ALG_DES = 0x0000,
 	SEAL_ALG_1 = 0x0001,		/* not published */
 	SEAL_ALG_DES3KD = 0x0002
 };

 #define CKSUMTYPE_CRC32			0x0001
 #define CKSUMTYPE_RSA_MD4		0x0002
 #define CKSUMTYPE_RSA_MD4_DES		0x0003
 #define CKSUMTYPE_DESCBC		0x0004
 #define CKSUMTYPE_RSA_MD5		0x0007
 #define CKSUMTYPE_RSA_MD5_DES		0x0008
 #define CKSUMTYPE_NIST_SHA		0x0009
 #define CKSUMTYPE_HMAC_SHA1_DES3	0x000c
 #define CKSUMTYPE_HMAC_SHA1_96_AES128   0x000f
 #define CKSUMTYPE_HMAC_SHA1_96_AES256   0x0010
 #define CKSUMTYPE_HMAC_MD5_ARCFOUR      -138 /* Microsoft md5 hmac cksumtype */

 /* from gssapi_err_krb5.h */
 #define KG_CCACHE_NOMATCH                        (39756032L)
 #define KG_KEYTAB_NOMATCH                        (39756033L)
 #define KG_TGT_MISSING                           (39756034L)
 #define KG_NO_SUBKEY                             (39756035L)
 #define KG_CONTEXT_ESTABLISHED                   (39756036L)
 #define KG_BAD_SIGN_TYPE                         (39756037L)
 #define KG_BAD_LENGTH                            (39756038L)
 #define KG_CTX_INCOMPLETE                        (39756039L)
 #define KG_CONTEXT                               (39756040L)
 #define KG_CRED                                  (39756041L)
 #define KG_ENC_DESC                              (39756042L)
 #define KG_BAD_SEQ                               (39756043L)
 #define KG_EMPTY_CCACHE                          (39756044L)
 #define KG_NO_CTYPES                             (39756045L)

 /* per Kerberos v5 protocol spec crypto types from the wire.
  * these get mapped to linux kernel crypto routines.
  */
 #define ENCTYPE_NULL            0x0000
 #define ENCTYPE_DES_CBC_CRC     0x0001	/* DES cbc mode with CRC-32 */
 #define ENCTYPE_DES_CBC_MD4     0x0002	/* DES cbc mode with RSA-MD4 */
 #define ENCTYPE_DES_CBC_MD5     0x0003	/* DES cbc mode with RSA-MD5 */
 #define ENCTYPE_DES_CBC_RAW     0x0004	/* DES cbc mode raw */
 /* XXX deprecated? */
 #define ENCTYPE_DES3_CBC_SHA    0x0005	/* DES-3 cbc mode with NIST-SHA */
 #define ENCTYPE_DES3_CBC_RAW    0x0006	/* DES-3 cbc mode raw */
 #define ENCTYPE_DES_HMAC_SHA1   0x0008
 #define ENCTYPE_DES3_CBC_SHA1   0x0010
 #define ENCTYPE_AES128_CTS_HMAC_SHA1_96 0x0011
 #define ENCTYPE_AES256_CTS_HMAC_SHA1_96 0x0012
 #define ENCTYPE_ARCFOUR_HMAC            0x0017
 #define ENCTYPE_ARCFOUR_HMAC_EXP        0x0018
 #define ENCTYPE_UNKNOWN         0x01ff

 /*
  * Constants used for key derivation
  */
 /* for 3DES */
 #define KG_USAGE_SEAL (22)
 #define KG_USAGE_SIGN (23)
 #define KG_USAGE_SEQ  (24)

 /* from rfc3961 */
 #define KEY_USAGE_SEED_CHECKSUM         (0x99)
 #define KEY_USAGE_SEED_ENCRYPTION       (0xAA)
 #define KEY_USAGE_SEED_INTEGRITY        (0x55)

 /* from rfc4121 */
 #define KG_USAGE_ACCEPTOR_SEAL  (22)
 #define KG_USAGE_ACCEPTOR_SIGN  (23)
 #define KG_USAGE_INITIATOR_SEAL (24)
 #define KG_USAGE_INITIATOR_SIGN (25)

 /*
  * This compile-time check verifies that we will not exceed the
  * slack space allotted by the client and server auth_gss code
  * before they call gss_wrap().
  */
 #define GSS_KRB5_MAX_SLACK_NEEDED \
 	(GSS_KRB5_TOK_HDR_LEN     /* gss token header */         \
 	+ GSS_KRB5_MAX_CKSUM_LEN  /* gss token checksum */       \
 	+ GSS_KRB5_MAX_BLOCKSIZE  /* confounder */               \
 	+ GSS_KRB5_MAX_BLOCKSIZE  /* possible padding */         \
 	+ GSS_KRB5_TOK_HDR_LEN    /* encrypted hdr in v2 token */\
 	+ GSS_KRB5_MAX_CKSUM_LEN  /* encryption hmac */          \
 	+ 4 + 4                   /* RPC verifier */             \
 	+ GSS_KRB5_TOK_HDR_LEN                                   \
 	+ GSS_KRB5_MAX_CKSUM_LEN)

 u32
 make_checksum(struct krb5_ctx *kctx, char *header, int hdrlen,
 		struct xdr_buf *body, int body_offset, u8 *cksumkey,
 		unsigned int usage, struct xdr_netobj *cksumout);

 u32
 make_checksum_v2(struct krb5_ctx *, char *header, int hdrlen,
 		 struct xdr_buf *body, int body_offset, u8 *key,
 		 unsigned int usage, struct xdr_netobj *cksum);

 u32 gss_get_mic_kerberos(struct gss_ctx *, struct xdr_buf *,
 		struct xdr_netobj *);

 u32 gss_verify_mic_kerberos(struct gss_ctx *, struct xdr_buf *,
 		struct xdr_netobj *);

 u32
 gss_wrap_kerberos(struct gss_ctx *ctx_id, int offset,
 		struct xdr_buf *outbuf, struct page **pages);

 u32
 gss_unwrap_kerberos(struct gss_ctx *ctx_id, int offset, int len,
 		struct xdr_buf *buf);


 u32
 krb5_encrypt(struct crypto_sync_skcipher *key,
 	     void *iv, void *in, void *out, int length);

 u32
 krb5_decrypt(struct crypto_sync_skcipher *key,
 	     void *iv, void *in, void *out, int length);

 int
 gss_encrypt_xdr_buf(struct crypto_sync_skcipher *tfm, struct xdr_buf *outbuf,
 		    int offset, struct page **pages);

 int
 gss_decrypt_xdr_buf(struct crypto_sync_skcipher *tfm, struct xdr_buf *inbuf,
 		    int offset);

 s32
 krb5_make_seq_num(struct krb5_ctx *kctx,
 		struct crypto_sync_skcipher *key,
 		int direction,
 		u32 seqnum, unsigned char *cksum, unsigned char *buf);

 s32
 krb5_get_seq_num(struct krb5_ctx *kctx,
 	       unsigned char *cksum,
 	       unsigned char *buf, int *direction, u32 *seqnum);

 int
 xdr_extend_head(struct xdr_buf *buf, unsigned int base, unsigned int shiftlen);

 u32
 krb5_derive_key(const struct gss_krb5_enctype *gk5e,
 		const struct xdr_netobj *inkey,
 		struct xdr_netobj *outkey,
 		const struct xdr_netobj *in_constant,
 		gfp_t gfp_mask);

 u32
 gss_krb5_des3_make_key(const struct gss_krb5_enctype *gk5e,
 		       struct xdr_netobj *randombits,
 		       struct xdr_netobj *key);

 u32
 gss_krb5_aes_make_key(const struct gss_krb5_enctype *gk5e,
 		      struct xdr_netobj *randombits,
 		      struct xdr_netobj *key);

 u32
 gss_krb5_aes_encrypt(struct krb5_ctx *kctx, u32 offset,
 		     struct xdr_buf *buf,
 		     struct page **pages);

 u32
 gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
 		     struct xdr_buf *buf, u32 *plainoffset,
 		     u32 *plainlen);

 void
 gss_krb5_make_confounder(char *p, u32 conflen);
	/*
	* linux/include/linux/sunrpc/gss_krb5_types.h
	*
	* Adapted from MIT Kerberos 5-1.2.1 lib/include/krb5.h,
	* lib/gssapi/krb5/gssapiP_krb5.h, and others
	*
	* Copyright (c) 2000-2008 The Regents of the University of Michigan.
	* All rights reserved.
	*
	* Andy Adamson <andros@umich.edu>
	* Bruce Fields <bfields@umich.edu>
	*/

	/*
	* Copyright 1995 by the Massachusetts Institute of Technology.
	* All Rights Reserved.
	*
	* Export of this software from the United States of America may
	* require a specific license from the United States Government.
	* It is the responsibility of any person or organization contemplating
	* export to obtain such a license before exporting.
	*
	* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
	* distribute this software and its documentation for any purpose and
	* without fee is hereby granted, provided that the above copyright
	* notice appear in all copies and that both that copyright notice and
	* this permission notice appear in supporting documentation, and that
	* the name of M.I.T. not be used in advertising or publicity pertaining
	* to distribution of the software without specific, written prior
	* permission. Furthermore if you modify this software you must label
	* your software as modified software and not distribute it in such a
	* fashion that it might be confused with the original M.I.T. software.
	* M.I.T. makes no representations about the suitability of
	* this software for any purpose. It is provided "as is" without express
	* or implied warranty.
	*
	*/

	#include <crypto/skcipher.h>
	#include <linux/sunrpc/auth_gss.h>
	#include <linux/sunrpc/gss_err.h>
	#include <linux/sunrpc/gss_asn1.h>

	/* Length of constant used in key derivation */
	#define GSS_KRB5_K5CLENGTH (5)

	/* Maximum key length (in bytes) for the supported crypto algorithms*/
	#define GSS_KRB5_MAX_KEYLEN (32)

	/* Maximum checksum function output for the supported crypto algorithms */
	#define GSS_KRB5_MAX_CKSUM_LEN (20)

	/* Maximum blocksize for the supported crypto algorithms */
	#define GSS_KRB5_MAX_BLOCKSIZE (16)

	struct krb5_ctx;

	struct gss_krb5_enctype {
	const u32 etype; /* encryption (key) type */
	const u32 ctype; /* checksum type */
	const char name; / "friendly" name */
	const char encrypt_name; / crypto encrypt name */
	const char cksum_name; / crypto checksum name */
	const u16 signalg; /* signing algorithm */
	const u16 sealalg; /* sealing algorithm */
	const u32 blocksize; /* encryption blocksize */
	const u32 conflen; /* confounder length
	(normally the same as
	the blocksize) */
	const u32 cksumlength; /* checksum length */
	const u32 keyed_cksum; /* is it a keyed cksum? */
	const u32 keybytes; /* raw key len, in bytes */
	const u32 keylength; /* final key len, in bytes */
	u32 (encrypt) (struct crypto_sync_skcipher tfm,
	void iv, void in, void *out,
	int length); /* encryption function */
	u32 (decrypt) (struct crypto_sync_skcipher tfm,
	void iv, void in, void *out,
	int length); /* decryption function */
	u32 (mk_key) (const struct gss_krb5_enctype gk5e,
	struct xdr_netobj *in,
	struct xdr_netobj out); / complete key generation */
	u32 (encrypt_v2) (struct krb5_ctx kctx, u32 offset,
	struct xdr_buf *buf,
	struct page *pages); / v2 encryption function */
	u32 (decrypt_v2) (struct krb5_ctx kctx, u32 offset, u32 len,
	struct xdr_buf buf, u32 headskip,
	u32 tailskip); / v2 decryption function */
	};

	/* krb5_ctx flags definitions */
	#define KRB5_CTX_FLAG_INITIATOR 0x00000001
	#define KRB5_CTX_FLAG_CFX 0x00000002
	#define KRB5_CTX_FLAG_ACCEPTOR_SUBKEY 0x00000004

	struct krb5_ctx {
	int initiate; /* 1 = initiating, 0 = accepting */
	u32 enctype;
	u32 flags;
	const struct gss_krb5_enctype gk5e; / enctype-specific info */
	struct crypto_sync_skcipher *enc;
	struct crypto_sync_skcipher *seq;
	struct crypto_sync_skcipher *acceptor_enc;
	struct crypto_sync_skcipher *initiator_enc;
	struct crypto_sync_skcipher *acceptor_enc_aux;
	struct crypto_sync_skcipher *initiator_enc_aux;
	u8 Ksess[GSS_KRB5_MAX_KEYLEN]; /* session key */
	u8 cksum[GSS_KRB5_MAX_KEYLEN];
	atomic_t seq_send;
	atomic64_t seq_send64;
	time64_t endtime;
	struct xdr_netobj mech_used;
	u8 initiator_sign[GSS_KRB5_MAX_KEYLEN];
	u8 acceptor_sign[GSS_KRB5_MAX_KEYLEN];
	u8 initiator_seal[GSS_KRB5_MAX_KEYLEN];
	u8 acceptor_seal[GSS_KRB5_MAX_KEYLEN];
	u8 initiator_integ[GSS_KRB5_MAX_KEYLEN];
	u8 acceptor_integ[GSS_KRB5_MAX_KEYLEN];
	};

	/* The length of the Kerberos GSS token header */
	#define GSS_KRB5_TOK_HDR_LEN (16)

	#define KG_TOK_MIC_MSG 0x0101
	#define KG_TOK_WRAP_MSG 0x0201

	#define KG2_TOK_INITIAL 0x0101
	#define KG2_TOK_RESPONSE 0x0202
	#define KG2_TOK_MIC 0x0404
	#define KG2_TOK_WRAP 0x0504

	#define KG2_TOKEN_FLAG_SENTBYACCEPTOR 0x01
	#define KG2_TOKEN_FLAG_SEALED 0x02
	#define KG2_TOKEN_FLAG_ACCEPTORSUBKEY 0x04

	#define KG2_RESP_FLAG_ERROR 0x0001
	#define KG2_RESP_FLAG_DELEG_OK 0x0002

	enum sgn_alg {
	SGN_ALG_DES_MAC_MD5 = 0x0000,
	SGN_ALG_MD2_5 = 0x0001,
	SGN_ALG_DES_MAC = 0x0002,
	SGN_ALG_3 = 0x0003, /* not published */
	SGN_ALG_HMAC_SHA1_DES3_KD = 0x0004
	};
	enum seal_alg {
	SEAL_ALG_NONE = 0xffff,
	SEAL_ALG_DES = 0x0000,
	SEAL_ALG_1 = 0x0001, /* not published */
	SEAL_ALG_DES3KD = 0x0002
	};

	#define CKSUMTYPE_CRC32 0x0001
	#define CKSUMTYPE_RSA_MD4 0x0002
	#define CKSUMTYPE_RSA_MD4_DES 0x0003
	#define CKSUMTYPE_DESCBC 0x0004
	#define CKSUMTYPE_RSA_MD5 0x0007
	#define CKSUMTYPE_RSA_MD5_DES 0x0008
	#define CKSUMTYPE_NIST_SHA 0x0009
	#define CKSUMTYPE_HMAC_SHA1_DES3 0x000c
	#define CKSUMTYPE_HMAC_SHA1_96_AES128 0x000f
	#define CKSUMTYPE_HMAC_SHA1_96_AES256 0x0010
	#define CKSUMTYPE_HMAC_MD5_ARCFOUR -138 /* Microsoft md5 hmac cksumtype */

	/* from gssapi_err_krb5.h */
	#define KG_CCACHE_NOMATCH (39756032L)
	#define KG_KEYTAB_NOMATCH (39756033L)
	#define KG_TGT_MISSING (39756034L)
	#define KG_NO_SUBKEY (39756035L)
	#define KG_CONTEXT_ESTABLISHED (39756036L)
	#define KG_BAD_SIGN_TYPE (39756037L)
	#define KG_BAD_LENGTH (39756038L)
	#define KG_CTX_INCOMPLETE (39756039L)
	#define KG_CONTEXT (39756040L)
	#define KG_CRED (39756041L)
	#define KG_ENC_DESC (39756042L)
	#define KG_BAD_SEQ (39756043L)
	#define KG_EMPTY_CCACHE (39756044L)
	#define KG_NO_CTYPES (39756045L)

	/* per Kerberos v5 protocol spec crypto types from the wire.
	* these get mapped to linux kernel crypto routines.
	*/
	#define ENCTYPE_NULL 0x0000
	#define ENCTYPE_DES_CBC_CRC 0x0001 /* DES cbc mode with CRC-32 */
	#define ENCTYPE_DES_CBC_MD4 0x0002 /* DES cbc mode with RSA-MD4 */
	#define ENCTYPE_DES_CBC_MD5 0x0003 /* DES cbc mode with RSA-MD5 */
	#define ENCTYPE_DES_CBC_RAW 0x0004 /* DES cbc mode raw */
	/* XXX deprecated? */
	#define ENCTYPE_DES3_CBC_SHA 0x0005 /* DES-3 cbc mode with NIST-SHA */
	#define ENCTYPE_DES3_CBC_RAW 0x0006 /* DES-3 cbc mode raw */
	#define ENCTYPE_DES_HMAC_SHA1 0x0008
	#define ENCTYPE_DES3_CBC_SHA1 0x0010
	#define ENCTYPE_AES128_CTS_HMAC_SHA1_96 0x0011
	#define ENCTYPE_AES256_CTS_HMAC_SHA1_96 0x0012
	#define ENCTYPE_ARCFOUR_HMAC 0x0017
	#define ENCTYPE_ARCFOUR_HMAC_EXP 0x0018
	#define ENCTYPE_UNKNOWN 0x01ff

	/*
	* Constants used for key derivation
	*/
	/* for 3DES */
	#define KG_USAGE_SEAL (22)
	#define KG_USAGE_SIGN (23)
	#define KG_USAGE_SEQ (24)

	/* from rfc3961 */
	#define KEY_USAGE_SEED_CHECKSUM (0x99)
	#define KEY_USAGE_SEED_ENCRYPTION (0xAA)
	#define KEY_USAGE_SEED_INTEGRITY (0x55)

	/* from rfc4121 */
	#define KG_USAGE_ACCEPTOR_SEAL (22)
	#define KG_USAGE_ACCEPTOR_SIGN (23)
	#define KG_USAGE_INITIATOR_SEAL (24)
	#define KG_USAGE_INITIATOR_SIGN (25)

	/*
	* This compile-time check verifies that we will not exceed the
	* slack space allotted by the client and server auth_gss code
	* before they call gss_wrap().
	*/
	#define GSS_KRB5_MAX_SLACK_NEEDED \
	(GSS_KRB5_TOK_HDR_LEN /* gss token header */ \
	+ GSS_KRB5_MAX_CKSUM_LEN /* gss token checksum */ \
	+ GSS_KRB5_MAX_BLOCKSIZE /* confounder */ \
	+ GSS_KRB5_MAX_BLOCKSIZE /* possible padding */ \
	+ GSS_KRB5_TOK_HDR_LEN /* encrypted hdr in v2 token */\
	+ GSS_KRB5_MAX_CKSUM_LEN /* encryption hmac */ \
	+ 4 + 4 /* RPC verifier */ \
	+ GSS_KRB5_TOK_HDR_LEN \
	+ GSS_KRB5_MAX_CKSUM_LEN)

	u32
	make_checksum(struct krb5_ctx kctx, char header, int hdrlen,
	struct xdr_buf body, int body_offset, u8 cksumkey,
	unsigned int usage, struct xdr_netobj *cksumout);

	u32
	make_checksum_v2(struct krb5_ctx , char header, int hdrlen,
	struct xdr_buf body, int body_offset, u8 key,
	unsigned int usage, struct xdr_netobj *cksum);

	u32 gss_get_mic_kerberos(struct gss_ctx , struct xdr_buf ,
	struct xdr_netobj *);

	u32 gss_verify_mic_kerberos(struct gss_ctx , struct xdr_buf ,
	struct xdr_netobj *);

	u32
	gss_wrap_kerberos(struct gss_ctx *ctx_id, int offset,
	struct xdr_buf outbuf, struct page *pages);

	u32
	gss_unwrap_kerberos(struct gss_ctx *ctx_id, int offset, int len,
	struct xdr_buf *buf);


	u32
	krb5_encrypt(struct crypto_sync_skcipher *key,
	void iv, void in, void *out, int length);

	u32
	krb5_decrypt(struct crypto_sync_skcipher *key,
	void iv, void in, void *out, int length);

	int
	gss_encrypt_xdr_buf(struct crypto_sync_skcipher tfm, struct xdr_buf outbuf,
	int offset, struct page **pages);

	int
	gss_decrypt_xdr_buf(struct crypto_sync_skcipher tfm, struct xdr_buf inbuf,
	int offset);

	s32
	krb5_make_seq_num(struct krb5_ctx *kctx,
	struct crypto_sync_skcipher *key,
	int direction,
	u32 seqnum, unsigned char cksum, unsigned char buf);

	s32
	krb5_get_seq_num(struct krb5_ctx *kctx,
	unsigned char *cksum,
	unsigned char buf, int direction, u32 *seqnum);

	int
	xdr_extend_head(struct xdr_buf *buf, unsigned int base, unsigned int shiftlen);

	u32
	krb5_derive_key(const struct gss_krb5_enctype *gk5e,
	const struct xdr_netobj *inkey,
	struct xdr_netobj *outkey,
	const struct xdr_netobj *in_constant,
	gfp_t gfp_mask);

	u32
	gss_krb5_des3_make_key(const struct gss_krb5_enctype *gk5e,
	struct xdr_netobj *randombits,
	struct xdr_netobj *key);

	u32
	gss_krb5_aes_make_key(const struct gss_krb5_enctype *gk5e,
	struct xdr_netobj *randombits,
	struct xdr_netobj *key);

	u32
	gss_krb5_aes_encrypt(struct krb5_ctx *kctx, u32 offset,
	struct xdr_buf *buf,
	struct page **pages);

	u32
	gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
	struct xdr_buf buf, u32 plainoffset,
	u32 *plainlen);

	void
	gss_krb5_make_confounder(char *p, u32 conflen);