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DEFINITIONS
This source file includes following definitions.
- krb5_encrypt
- krb5_decrypt
- checksummer
- make_checksum
- encryptor
- gss_encrypt_xdr_buf
- decryptor
- gss_decrypt_xdr_buf
/*
* linux/net/sunrpc/gss_krb5_crypto.c
*
* Copyright (c) 2000 The Regents of the University of Michigan.
* All rights reserved.
*
* Andy Adamson <andros@umich.edu>
* Bruce Fields <bfields@umich.edu>
*/
/*
* 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/err.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/scatterlist.h>
#include <linux/crypto.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/sunrpc/gss_krb5.h>
#include <linux/sunrpc/xdr.h>
#ifdef RPC_DEBUG
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
u32
krb5_encrypt(
struct crypto_blkcipher *tfm,
void * iv,
void * in,
void * out,
int length)
{
u32 ret = -EINVAL;
struct scatterlist sg[1];
u8 local_iv[16] = {0};
struct blkcipher_desc desc = { .tfm = tfm, .info = local_iv };
if (length % crypto_blkcipher_blocksize(tfm) != 0)
goto out;
if (crypto_blkcipher_ivsize(tfm) > 16) {
dprintk("RPC: gss_k5encrypt: tfm iv size too large %d\n",
crypto_blkcipher_ivsize(tfm));
goto out;
}
if (iv)
memcpy(local_iv, iv, crypto_blkcipher_ivsize(tfm));
memcpy(out, in, length);
sg_init_one(sg, out, length);
ret = crypto_blkcipher_encrypt_iv(&desc, sg, sg, length);
out:
dprintk("RPC: krb5_encrypt returns %d\n", ret);
return ret;
}
u32
krb5_decrypt(
struct crypto_blkcipher *tfm,
void * iv,
void * in,
void * out,
int length)
{
u32 ret = -EINVAL;
struct scatterlist sg[1];
u8 local_iv[16] = {0};
struct blkcipher_desc desc = { .tfm = tfm, .info = local_iv };
if (length % crypto_blkcipher_blocksize(tfm) != 0)
goto out;
if (crypto_blkcipher_ivsize(tfm) > 16) {
dprintk("RPC: gss_k5decrypt: tfm iv size too large %d\n",
crypto_blkcipher_ivsize(tfm));
goto out;
}
if (iv)
memcpy(local_iv,iv, crypto_blkcipher_ivsize(tfm));
memcpy(out, in, length);
sg_init_one(sg, out, length);
ret = crypto_blkcipher_decrypt_iv(&desc, sg, sg, length);
out:
dprintk("RPC: gss_k5decrypt returns %d\n",ret);
return ret;
}
static int
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_checksum(char *cksumname, char *header, int hdrlen, struct xdr_buf *body,
int body_offset, struct xdr_netobj *cksum)
{
struct hash_desc desc; /* XXX add to ctx? */
struct scatterlist sg[1];
int err;
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_init(&desc);
if (err)
goto out;
sg_init_one(sg, header, hdrlen);
err = crypto_hash_update(&desc, sg, hdrlen);
if (err)
goto out;
err = xdr_process_buf(body, body_offset, body->len - body_offset,
checksummer, &desc);
if (err)
goto out;
err = crypto_hash_final(&desc, cksum->data);
out:
crypto_free_hash(desc.tfm);
return err ? GSS_S_FAILURE : 0;
}
struct encryptor_desc {
u8 iv[8]; /* XXX hard-coded blocksize */
struct blkcipher_desc desc;
int pos;
struct xdr_buf *outbuf;
struct page **pages;
struct scatterlist infrags[4];
struct scatterlist outfrags[4];
int fragno;
int fraglen;
};
static int
encryptor(struct scatterlist *sg, void *data)
{
struct encryptor_desc *desc = data;
struct xdr_buf *outbuf = desc->outbuf;
struct page *in_page;
int thislen = desc->fraglen + sg->length;
int fraglen, ret;
int page_pos;
/* Worst case is 4 fragments: head, end of page 1, start
* of page 2, tail. Anything more is a bug. */
BUG_ON(desc->fragno > 3);
page_pos = desc->pos - outbuf->head[0].iov_len;
if (page_pos >= 0 && page_pos < outbuf->page_len) {
/* pages are not in place: */
int i = (page_pos + outbuf->page_base) >> PAGE_CACHE_SHIFT;
in_page = desc->pages[i];
} else {
in_page = sg_page(sg);
}
sg_set_page(&desc->infrags[desc->fragno], in_page, sg->length,
sg->offset);
sg_set_page(&desc->outfrags[desc->fragno], sg_page(sg), sg->length,
sg->offset);
desc->fragno++;
desc->fraglen += sg->length;
desc->pos += sg->length;
fraglen = thislen & 7; /* XXX hardcoded blocksize */
thislen -= fraglen;
if (thislen == 0)
return 0;
sg_mark_end(&desc->infrags[desc->fragno - 1]);
sg_mark_end(&desc->outfrags[desc->fragno - 1]);
ret = crypto_blkcipher_encrypt_iv(&desc->desc, desc->outfrags,
desc->infrags, thislen);
if (ret)
return ret;
sg_init_table(desc->infrags, 4);
sg_init_table(desc->outfrags, 4);
if (fraglen) {
sg_set_page(&desc->outfrags[0], sg_page(sg), fraglen,
sg->offset + sg->length - fraglen);
desc->infrags[0] = desc->outfrags[0];
sg_assign_page(&desc->infrags[0], in_page);
desc->fragno = 1;
desc->fraglen = fraglen;
} else {
desc->fragno = 0;
desc->fraglen = 0;
}
return 0;
}
int
gss_encrypt_xdr_buf(struct crypto_blkcipher *tfm, struct xdr_buf *buf,
int offset, struct page **pages)
{
int ret;
struct encryptor_desc desc;
BUG_ON((buf->len - offset) % crypto_blkcipher_blocksize(tfm) != 0);
memset(desc.iv, 0, sizeof(desc.iv));
desc.desc.tfm = tfm;
desc.desc.info = desc.iv;
desc.desc.flags = 0;
desc.pos = offset;
desc.outbuf = buf;
desc.pages = pages;
desc.fragno = 0;
desc.fraglen = 0;
sg_init_table(desc.infrags, 4);
sg_init_table(desc.outfrags, 4);
ret = xdr_process_buf(buf, offset, buf->len - offset, encryptor, &desc);
return ret;
}
struct decryptor_desc {
u8 iv[8]; /* XXX hard-coded blocksize */
struct blkcipher_desc desc;
struct scatterlist frags[4];
int fragno;
int fraglen;
};
static int
decryptor(struct scatterlist *sg, void *data)
{
struct decryptor_desc *desc = data;
int thislen = desc->fraglen + sg->length;
int fraglen, ret;
/* Worst case is 4 fragments: head, end of page 1, start
* of page 2, tail. Anything more is a bug. */
BUG_ON(desc->fragno > 3);
sg_set_page(&desc->frags[desc->fragno], sg_page(sg), sg->length,
sg->offset);
desc->fragno++;
desc->fraglen += sg->length;
fraglen = thislen & 7; /* XXX hardcoded blocksize */
thislen -= fraglen;
if (thislen == 0)
return 0;
sg_mark_end(&desc->frags[desc->fragno - 1]);
ret = crypto_blkcipher_decrypt_iv(&desc->desc, desc->frags,
desc->frags, thislen);
if (ret)
return ret;
sg_init_table(desc->frags, 4);
if (fraglen) {
sg_set_page(&desc->frags[0], sg_page(sg), fraglen,
sg->offset + sg->length - fraglen);
desc->fragno = 1;
desc->fraglen = fraglen;
} else {
desc->fragno = 0;
desc->fraglen = 0;
}
return 0;
}
int
gss_decrypt_xdr_buf(struct crypto_blkcipher *tfm, struct xdr_buf *buf,
int offset)
{
struct decryptor_desc desc;
/* XXXJBF: */
BUG_ON((buf->len - offset) % crypto_blkcipher_blocksize(tfm) != 0);
memset(desc.iv, 0, sizeof(desc.iv));
desc.desc.tfm = tfm;
desc.desc.info = desc.iv;
desc.desc.flags = 0;
desc.fragno = 0;
desc.fraglen = 0;
sg_init_table(desc.frags, 4);
return xdr_process_buf(buf, offset, buf->len - offset, decryptor, &desc);
}