net/sunrpc/auth_gss/gss_krb5_seal.c - third_party/kernel - Git at Google

 /*
  *  linux/net/sunrpc/gss_krb5_seal.c
  *
  *  Adapted from MIT Kerberos 5-1.2.1 lib/gssapi/krb5/k5seal.c
  *
  *  Copyright (c) 2000-2008 The Regents of the University of Michigan.
  *  All rights reserved.
  *
  *  Andy Adamson	<andros@umich.edu>
  *  J. Bruce Fields	<bfields@umich.edu>
  */

 /*
  * Copyright 1993 by OpenVision Technologies, Inc.
  *
  * Permission to use, copy, modify, distribute, and sell this software
  * and its documentation for any purpose is hereby granted without fee,
  * provided that the above copyright notice appears in all copies and
  * that both that copyright notice and this permission notice appear in
  * supporting documentation, and that the name of OpenVision not be used
  * in advertising or publicity pertaining to distribution of the software
  * without specific, written prior permission. OpenVision makes no
  * representations about the suitability of this software for any
  * purpose.  It is provided "as is" without express or implied warranty.
  *
  * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
  * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
  * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  * PERFORMANCE OF THIS SOFTWARE.
  */

 /*
  * Copyright (C) 1998 by the FundsXpress, INC.
  *
  * 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 FundsXpress. not be used in advertising or publicity pertaining
  * to distribution of the software without specific, written prior
  * permission.  FundsXpress makes no representations about the suitability of
  * this software for any purpose.  It is provided "as is" without express
  * or implied warranty.
  *
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  */

 #include <linux/types.h>
 #include <linux/jiffies.h>
 #include <linux/sunrpc/gss_krb5.h>
 #include <linux/random.h>
 #include <linux/crypto.h>
 #include <linux/atomic.h>

 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 # define RPCDBG_FACILITY        RPCDBG_AUTH
 #endif

 static void *
 setup_token(struct krb5_ctx *ctx, struct xdr_netobj *token)
 {
 	u16 *ptr;
 	void *krb5_hdr;
 	int body_size = GSS_KRB5_TOK_HDR_LEN + ctx->gk5e->cksumlength;

 	token->len = g_token_size(&ctx->mech_used, body_size);

 	ptr = (u16 *)token->data;
 	g_make_token_header(&ctx->mech_used, body_size, (unsigned char **)&ptr);

 	/* ptr now at start of header described in rfc 1964, section 1.2.1: */
 	krb5_hdr = ptr;
 	*ptr++ = KG_TOK_MIC_MSG;
 	/*
 	 * signalg is stored as if it were converted from LE to host endian, even
 	 * though it's an opaque pair of bytes according to the RFC.
 	 */
 	*ptr++ = (__force u16)cpu_to_le16(ctx->gk5e->signalg);
 	*ptr++ = SEAL_ALG_NONE;
 	*ptr = 0xffff;

 	return krb5_hdr;
 }

 static void *
 setup_token_v2(struct krb5_ctx *ctx, struct xdr_netobj *token)
 {
 	u16 *ptr;
 	void *krb5_hdr;
 	u8 *p, flags = 0x00;

 	if ((ctx->flags & KRB5_CTX_FLAG_INITIATOR) == 0)
 		flags |= 0x01;
 	if (ctx->flags & KRB5_CTX_FLAG_ACCEPTOR_SUBKEY)
 		flags |= 0x04;

 	/* Per rfc 4121, sec 4.2.6.1, there is no header,
 	 * just start the token */
 	krb5_hdr = ptr = (u16 *)token->data;

 	*ptr++ = KG2_TOK_MIC;
 	p = (u8 *)ptr;
 	*p++ = flags;
 	*p++ = 0xff;
 	ptr = (u16 *)p;
 	*ptr++ = 0xffff;
 	*ptr = 0xffff;

 	token->len = GSS_KRB5_TOK_HDR_LEN + ctx->gk5e->cksumlength;
 	return krb5_hdr;
 }

 static u32
 gss_get_mic_v1(struct krb5_ctx *ctx, struct xdr_buf *text,
 		struct xdr_netobj *token)
 {
 	char			cksumdata[GSS_KRB5_MAX_CKSUM_LEN];
 	struct xdr_netobj	md5cksum = {.len = sizeof(cksumdata),
 					    .data = cksumdata};
 	void			*ptr;
 	time64_t		now;
 	u32			seq_send;
 	u8			*cksumkey;

 	dprintk("RPC:       %s\n", __func__);
 	BUG_ON(ctx == NULL);

 	now = ktime_get_real_seconds();

 	ptr = setup_token(ctx, token);

 	if (ctx->gk5e->keyed_cksum)
 		cksumkey = ctx->cksum;
 	else
 		cksumkey = NULL;

 	if (make_checksum(ctx, ptr, 8, text, 0, cksumkey,
 			  KG_USAGE_SIGN, &md5cksum))
 		return GSS_S_FAILURE;

 	memcpy(ptr + GSS_KRB5_TOK_HDR_LEN, md5cksum.data, md5cksum.len);

 	seq_send = atomic_fetch_inc(&ctx->seq_send);

 	if (krb5_make_seq_num(ctx, ctx->seq, ctx->initiate ? 0 : 0xff,
 			      seq_send, ptr + GSS_KRB5_TOK_HDR_LEN, ptr + 8))
 		return GSS_S_FAILURE;

 	return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE;
 }

 static u32
 gss_get_mic_v2(struct krb5_ctx *ctx, struct xdr_buf *text,
 		struct xdr_netobj *token)
 {
 	char cksumdata[GSS_KRB5_MAX_CKSUM_LEN];
 	struct xdr_netobj cksumobj = { .len = sizeof(cksumdata),
 				       .data = cksumdata};
 	void *krb5_hdr;
 	time64_t now;
 	u8 *cksumkey;
 	unsigned int cksum_usage;
 	__be64 seq_send_be64;

 	dprintk("RPC:       %s\n", __func__);

 	krb5_hdr = setup_token_v2(ctx, token);

 	/* Set up the sequence number. Now 64-bits in clear
 	 * text and w/o direction indicator */
 	seq_send_be64 = cpu_to_be64(atomic64_fetch_inc(&ctx->seq_send64));
 	memcpy(krb5_hdr + 8, (char *) &seq_send_be64, 8);

 	if (ctx->initiate) {
 		cksumkey = ctx->initiator_sign;
 		cksum_usage = KG_USAGE_INITIATOR_SIGN;
 	} else {
 		cksumkey = ctx->acceptor_sign;
 		cksum_usage = KG_USAGE_ACCEPTOR_SIGN;
 	}

 	if (make_checksum_v2(ctx, krb5_hdr, GSS_KRB5_TOK_HDR_LEN,
 			     text, 0, cksumkey, cksum_usage, &cksumobj))
 		return GSS_S_FAILURE;

 	memcpy(krb5_hdr + GSS_KRB5_TOK_HDR_LEN, cksumobj.data, cksumobj.len);

 	now = ktime_get_real_seconds();

 	return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE;
 }

 u32
 gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text,
 		     struct xdr_netobj *token)
 {
 	struct krb5_ctx		*ctx = gss_ctx->internal_ctx_id;

 	switch (ctx->enctype) {
 	default:
 		BUG();
 	case ENCTYPE_DES_CBC_RAW:
 	case ENCTYPE_DES3_CBC_RAW:
 		return gss_get_mic_v1(ctx, text, token);
 	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
 	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
 		return gss_get_mic_v2(ctx, text, token);
 	}
 }
	/*
	* linux/net/sunrpc/gss_krb5_seal.c
	*
	* Adapted from MIT Kerberos 5-1.2.1 lib/gssapi/krb5/k5seal.c
	*
	* Copyright (c) 2000-2008 The Regents of the University of Michigan.
	* All rights reserved.
	*
	* Andy Adamson <andros@umich.edu>
	* J. Bruce Fields <bfields@umich.edu>
	*/

	/*
	* Copyright 1993 by OpenVision Technologies, Inc.
	*
	* Permission to use, copy, modify, distribute, and sell this software
	* and its documentation for any purpose is hereby granted without fee,
	* provided that the above copyright notice appears in all copies and
	* that both that copyright notice and this permission notice appear in
	* supporting documentation, and that the name of OpenVision not be used
	* in advertising or publicity pertaining to distribution of the software
	* without specific, written prior permission. OpenVision makes no
	* representations about the suitability of this software for any
	* purpose. It is provided "as is" without express or implied warranty.
	*
	* OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
	* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
	* EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR
	* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
	* USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
	* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
	* PERFORMANCE OF THIS SOFTWARE.
	*/

	/*
	* Copyright (C) 1998 by the FundsXpress, INC.
	*
	* 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 FundsXpress. not be used in advertising or publicity pertaining
	* to distribution of the software without specific, written prior
	* permission. FundsXpress makes no representations about the suitability of
	* this software for any purpose. It is provided "as is" without express
	* or implied warranty.
	*
	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
	* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
	* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
	*/

	#include <linux/types.h>
	#include <linux/jiffies.h>
	#include <linux/sunrpc/gss_krb5.h>
	#include <linux/random.h>
	#include <linux/crypto.h>
	#include <linux/atomic.h>

	#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
	# define RPCDBG_FACILITY RPCDBG_AUTH
	#endif

	static void *
	setup_token(struct krb5_ctx ctx, struct xdr_netobj token)
	{
	u16 *ptr;
	void *krb5_hdr;
	int body_size = GSS_KRB5_TOK_HDR_LEN + ctx->gk5e->cksumlength;

	token->len = g_token_size(&ctx->mech_used, body_size);

	ptr = (u16 *)token->data;
	g_make_token_header(&ctx->mech_used, body_size, (unsigned char **)&ptr);

	/* ptr now at start of header described in rfc 1964, section 1.2.1: */
	krb5_hdr = ptr;
	*ptr++ = KG_TOK_MIC_MSG;
	/*
	* signalg is stored as if it were converted from LE to host endian, even
	* though it's an opaque pair of bytes according to the RFC.
	*/
	*ptr++ = (__force u16)cpu_to_le16(ctx->gk5e->signalg);
	*ptr++ = SEAL_ALG_NONE;
	*ptr = 0xffff;

	return krb5_hdr;
	}

	static void *
	setup_token_v2(struct krb5_ctx ctx, struct xdr_netobj token)
	{
	u16 *ptr;
	void *krb5_hdr;
	u8 *p, flags = 0x00;

	if ((ctx->flags & KRB5_CTX_FLAG_INITIATOR) == 0)
	flags \|= 0x01;
	if (ctx->flags & KRB5_CTX_FLAG_ACCEPTOR_SUBKEY)
	flags \|= 0x04;

	/* Per rfc 4121, sec 4.2.6.1, there is no header,
	* just start the token */
	krb5_hdr = ptr = (u16 *)token->data;

	*ptr++ = KG2_TOK_MIC;
	p = (u8 *)ptr;
	*p++ = flags;
	*p++ = 0xff;
	ptr = (u16 *)p;
	*ptr++ = 0xffff;
	*ptr = 0xffff;

	token->len = GSS_KRB5_TOK_HDR_LEN + ctx->gk5e->cksumlength;
	return krb5_hdr;
	}

	static u32
	gss_get_mic_v1(struct krb5_ctx ctx, struct xdr_buf text,
	struct xdr_netobj *token)
	{
	char cksumdata[GSS_KRB5_MAX_CKSUM_LEN];
	struct xdr_netobj md5cksum = {.len = sizeof(cksumdata),
	.data = cksumdata};
	void *ptr;
	time64_t now;
	u32 seq_send;
	u8 *cksumkey;

	dprintk("RPC: %s\n", __func__);
	BUG_ON(ctx == NULL);

	now = ktime_get_real_seconds();

	ptr = setup_token(ctx, token);

	if (ctx->gk5e->keyed_cksum)
	cksumkey = ctx->cksum;
	else
	cksumkey = NULL;

	if (make_checksum(ctx, ptr, 8, text, 0, cksumkey,
	KG_USAGE_SIGN, &md5cksum))
	return GSS_S_FAILURE;

	memcpy(ptr + GSS_KRB5_TOK_HDR_LEN, md5cksum.data, md5cksum.len);

	seq_send = atomic_fetch_inc(&ctx->seq_send);

	if (krb5_make_seq_num(ctx, ctx->seq, ctx->initiate ? 0 : 0xff,
	seq_send, ptr + GSS_KRB5_TOK_HDR_LEN, ptr + 8))
	return GSS_S_FAILURE;

	return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE;
	}

	static u32
	gss_get_mic_v2(struct krb5_ctx ctx, struct xdr_buf text,
	struct xdr_netobj *token)
	{
	char cksumdata[GSS_KRB5_MAX_CKSUM_LEN];
	struct xdr_netobj cksumobj = { .len = sizeof(cksumdata),
	.data = cksumdata};
	void *krb5_hdr;
	time64_t now;
	u8 *cksumkey;
	unsigned int cksum_usage;
	__be64 seq_send_be64;

	dprintk("RPC: %s\n", __func__);

	krb5_hdr = setup_token_v2(ctx, token);

	/* Set up the sequence number. Now 64-bits in clear
	* text and w/o direction indicator */
	seq_send_be64 = cpu_to_be64(atomic64_fetch_inc(&ctx->seq_send64));
	memcpy(krb5_hdr + 8, (char *) &seq_send_be64, 8);

	if (ctx->initiate) {
	cksumkey = ctx->initiator_sign;
	cksum_usage = KG_USAGE_INITIATOR_SIGN;
	} else {
	cksumkey = ctx->acceptor_sign;
	cksum_usage = KG_USAGE_ACCEPTOR_SIGN;
	}

	if (make_checksum_v2(ctx, krb5_hdr, GSS_KRB5_TOK_HDR_LEN,
	text, 0, cksumkey, cksum_usage, &cksumobj))
	return GSS_S_FAILURE;

	memcpy(krb5_hdr + GSS_KRB5_TOK_HDR_LEN, cksumobj.data, cksumobj.len);

	now = ktime_get_real_seconds();

	return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE;
	}

	u32
	gss_get_mic_kerberos(struct gss_ctx gss_ctx, struct xdr_buf text,
	struct xdr_netobj *token)
	{
	struct krb5_ctx *ctx = gss_ctx->internal_ctx_id;

	switch (ctx->enctype) {
	default:
	BUG();
	case ENCTYPE_DES_CBC_RAW:
	case ENCTYPE_DES3_CBC_RAW:
	return gss_get_mic_v1(ctx, text, token);
	case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
	case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
	return gss_get_mic_v2(ctx, text, token);
	}
	}