/*
* 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>
#if IS_ENABLED([31mCONFIG_SUNRPC_DEBUG[0m)
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
DEFINE_SPINLOCK(krb5_seq_lock);
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;
s32 now;
u32 seq_send;
u8 *cksumkey;
dprintk("RPC: %s\n", __func__);
BUG_ON(ctx == NULL);
now = get_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);
spin_lock(&krb5_seq_lock);
seq_send = ctx->seq_send++;
spin_unlock(&krb5_seq_lock);
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;
s32 now;
u64 seq_send;
u8 *cksumkey;
unsigned int cksum_usage;
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 */
spin_lock(&krb5_seq_lock);
seq_send = ctx->seq_send64++;
spin_unlock(&krb5_seq_lock);
*((__be64 *)(krb5_hdr + 8)) = cpu_to_be64(seq_send);
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 = get_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:
case ENCTYPE_ARCFOUR_HMAC:
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);
}
}