linux/net/sunrpc/auth_gss/gss_spkm3_seal.c

188 lines
5.5 KiB
C

/*
* linux/net/sunrpc/gss_spkm3_seal.c
*
* Copyright (c) 2003 The Regents of the University of Michigan.
* All rights reserved.
*
* Andy Adamson <andros@umich.edu>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/sunrpc/gss_spkm3.h>
#include <linux/random.h>
#include <linux/crypto.h>
#include <linux/pagemap.h>
#include <linux/scatterlist.h>
#include <linux/sunrpc/xdr.h>
#ifdef RPC_DEBUG
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
const struct xdr_netobj hmac_md5_oid = { 8, "\x2B\x06\x01\x05\x05\x08\x01\x01"};
const struct xdr_netobj cast5_cbc_oid = {9, "\x2A\x86\x48\x86\xF6\x7D\x07\x42\x0A"};
/*
* spkm3_make_token()
*
* Only SPKM_MIC_TOK with md5 intg-alg is supported
*/
u32
spkm3_make_token(struct spkm3_ctx *ctx,
struct xdr_buf * text, struct xdr_netobj * token,
int toktype)
{
s32 checksum_type;
char tokhdrbuf[25];
char cksumdata[16];
struct xdr_netobj md5cksum = {.len = 0, .data = cksumdata};
struct xdr_netobj mic_hdr = {.len = 0, .data = tokhdrbuf};
int tokenlen = 0;
unsigned char *ptr;
s32 now;
int ctxelen = 0, ctxzbit = 0;
int md5elen = 0, md5zbit = 0;
now = jiffies;
if (ctx->ctx_id.len != 16) {
dprintk("RPC: spkm3_make_token BAD ctx_id.len %d\n",
ctx->ctx_id.len);
goto out_err;
}
if (!g_OID_equal(&ctx->intg_alg, &hmac_md5_oid)) {
dprintk("RPC: gss_spkm3_seal: unsupported I-ALG "
"algorithm. only support hmac-md5 I-ALG.\n");
goto out_err;
} else
checksum_type = CKSUMTYPE_HMAC_MD5;
if (!g_OID_equal(&ctx->conf_alg, &cast5_cbc_oid)) {
dprintk("RPC: gss_spkm3_seal: unsupported C-ALG "
"algorithm\n");
goto out_err;
}
if (toktype == SPKM_MIC_TOK) {
/* Calculate checksum over the mic-header */
asn1_bitstring_len(&ctx->ctx_id, &ctxelen, &ctxzbit);
spkm3_mic_header(&mic_hdr.data, &mic_hdr.len, ctx->ctx_id.data,
ctxelen, ctxzbit);
if (make_spkm3_checksum(checksum_type, &ctx->derived_integ_key,
(char *)mic_hdr.data, mic_hdr.len,
text, 0, &md5cksum))
goto out_err;
asn1_bitstring_len(&md5cksum, &md5elen, &md5zbit);
tokenlen = 10 + ctxelen + 1 + md5elen + 1;
/* Create token header using generic routines */
token->len = g_token_size(&ctx->mech_used, tokenlen + 2);
ptr = token->data;
g_make_token_header(&ctx->mech_used, tokenlen + 2, &ptr);
spkm3_make_mic_token(&ptr, tokenlen, &mic_hdr, &md5cksum, md5elen, md5zbit);
} else if (toktype == SPKM_WRAP_TOK) { /* Not Supported */
dprintk("RPC: gss_spkm3_seal: SPKM_WRAP_TOK "
"not supported\n");
goto out_err;
}
/* XXX need to implement sequence numbers, and ctx->expired */
return GSS_S_COMPLETE;
out_err:
token->data = NULL;
token->len = 0;
return GSS_S_FAILURE;
}
static int
spkm3_checksummer(struct scatterlist *sg, void *data)
{
struct hash_desc *desc = data;
return crypto_hash_update(desc, sg, sg->length);
}
/* checksum the plaintext data and hdrlen bytes of the token header */
s32
make_spkm3_checksum(s32 cksumtype, struct xdr_netobj *key, char *header,
unsigned int hdrlen, struct xdr_buf *body,
unsigned int body_offset, struct xdr_netobj *cksum)
{
char *cksumname;
struct hash_desc desc; /* XXX add to ctx? */
struct scatterlist sg[1];
int err;
switch (cksumtype) {
case CKSUMTYPE_HMAC_MD5:
cksumname = "hmac(md5)";
break;
default:
dprintk("RPC: spkm3_make_checksum:"
" unsupported checksum %d", cksumtype);
return GSS_S_FAILURE;
}
if (key->data == NULL || key->len <= 0) return GSS_S_FAILURE;
desc.tfm = crypto_alloc_hash(cksumname, 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(desc.tfm))
return GSS_S_FAILURE;
cksum->len = crypto_hash_digestsize(desc.tfm);
desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
err = crypto_hash_setkey(desc.tfm, key->data, key->len);
if (err)
goto out;
err = crypto_hash_init(&desc);
if (err)
goto out;
sg_init_one(sg, header, hdrlen);
crypto_hash_update(&desc, sg, sg->length);
xdr_process_buf(body, body_offset, body->len - body_offset,
spkm3_checksummer, &desc);
crypto_hash_final(&desc, cksum->data);
out:
crypto_free_hash(desc.tfm);
return err ? GSS_S_FAILURE : 0;
}