cryptodev.c

linux下基于加密芯片的加密设备

/*	$OpenBSD: cryptodev.c,v 1.52 2002/06/19 07:22:46 deraadt Exp $	*/

/*
 * The linux port of this code done by David McCullough <[e-mail]>
 * The license and original author are listed below.
 * Copyright (C) 2004 David McCullough <[e-mail]>
 *
 * Copyright (c) 2001 Theo de Raadt
 *
 * 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. The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 *
 * Effort sponsored in part by the Defense Advanced Research Projects
 * Agency (DARPA) and Air Force Research Laboratory, Air Force
 * Materiel Command, USAF, under agreement number F30602-01-2-0537.
 */

static int errno = -1;
#define __KERNEL_SYSCALLS__ 1

#include <linux/config.h>
#include <linux/types.h>
#include <linux/time.h>
#include <linux/list.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/unistd.h>
#include <linux/module.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/miscdevice.h>
#include <asm/uaccess.h>

#include <cryptodev.h>
#include <uio.h>

static int debug = 0;
MODULE_PARM(debug, "i");
MODULE_PARM_DESC(debug,
	   "Enable debug");

static int crypto_devsel = 0;
MODULE_PARM(crypto_devsel, "i");
MODULE_PARM_DESC(crypto_devsel,
	   "Select cryptodev drivers: -1=software only, 1=HW only, 0=any");

struct csession_info {
	u_int16_t	blocksize;
	u_int16_t	minkey, maxkey;

	u_int16_t	keysize;
	/* u_int16_t	hashsize;  */
	u_int16_t	authsize;
	/* u_int16_t	ctxsize; */
};

struct csession {
	struct list_head	list;
	u_int64_t	sid;
	u_int32_t	ses;

	wait_queue_head_t waitq;

	u_int32_t	cipher;

	u_int32_t	mac;

	caddr_t		key;
	int		keylen;
	u_char		tmp_iv[EALG_MAX_BLOCK_LEN];

	caddr_t		mackey;
	int		mackeylen;
	u_char		tmp_mac[CRYPTO_MAX_MAC_LEN];

	struct csession_info info;

	struct iovec	iovec;
	struct uio	uio;
	int		error;
};

struct fcrypt {
	struct list_head	csessions;
	int		sesn;
};

static struct csession *csefind(struct fcrypt *, u_int);
static int csedelete(struct fcrypt *, struct csession *);
static struct csession *cseadd(struct fcrypt *, struct csession *);
static struct csession *csecreate(struct fcrypt *, u_int64_t,
		struct cryptoini *crie, struct cryptoini *cria, struct csession_info *);
static int csefree(struct csession *);

static	int cryptodev_op(struct csession *, struct crypt_op *);
static	int cryptodev_key(struct crypt_kop *);

static int cryptodev_cb(void *);

static int
cryptodev_op(struct csession *cse, struct crypt_op *cop)
{
	struct cryptop *crp = NULL;
	struct cryptodesc *crde = NULL, *crda = NULL;
	int error;

	dprintk("%s()\n", __FUNCTION__);
	if (cop->len > 256*1024-4) {
		dprintk("%s: %d > 256k\n", __FUNCTION__, cop->len);
		return (E2BIG);
	}

	if (cse->info.blocksize && (cop->len % cse->info.blocksize) != 0) {
		dprintk("%s: blocksize=%d len=%d\n", __FUNCTION__, cse->info.blocksize,
				cop->len);
		return (EINVAL);
	}

	cse->uio.uio_iov = &cse->iovec;
	cse->uio.uio_iovcnt = 1;
	cse->uio.uio_offset = 0;
#if 0
	cse->uio.uio_resid = cop->len;
	cse->uio.uio_segflg = UIO_SYSSPACE;
	cse->uio.uio_rw = UIO_WRITE;
	cse->uio.uio_td = td;
#endif
	cse->uio.uio_iov[0].iov_len = cop->len;
	cse->uio.uio_iov[0].iov_base = kmalloc(cop->len, GFP_KERNEL);

	crp = crypto_getreq((cse->info.blocksize != 0) + (cse->info.authsize != 0));
	if (crp == NULL) {
		dprintk("%s: ENOMEM\n", __FUNCTION__);
		error = ENOMEM;
		goto bail;
	}

	if (cse->info.authsize) {
		crda = crp->crp_desc;
		if (cse->info.blocksize)
			crde = crda->crd_next;
	} else {
		if (cse->info.blocksize)
			crde = crp->crp_desc;
		else {
			dprintk("%s: bad request\n", __FUNCTION__);
			error = EINVAL;
			goto bail;
		}
	}

	if ((error = copy_from_user(cse->uio.uio_iov[0].iov_base, cop->src,
					cop->len))) {
		dprintk("%s: bad copy\n", __FUNCTION__);
		goto bail;
	}

	if (crda) {
		crda->crd_skip = 0;
		crda->crd_len = cop->len;
		crda->crd_inject = 0;	/* ??? */

		crda->crd_alg = cse->mac;
		crda->crd_key = cse->mackey;
		crda->crd_klen = cse->mackeylen * 8;
	}

	if (crde) {
		if (cop->op == COP_ENCRYPT)
			crde->crd_flags |= CRD_F_ENCRYPT;
		else
			crde->crd_flags &= ~CRD_F_ENCRYPT;
		crde->crd_len = cop->len;
		crde->crd_inject = 0;

		crde->crd_alg = cse->cipher;
		crde->crd_key = cse->key;
		crde->crd_klen = cse->keylen * 8;
	}

	crp->crp_ilen = cop->len;
	crp->crp_flags = CRYPTO_F_IOV | CRYPTO_F_CBIMM
		       | (cop->flags & COP_F_BATCH);
	crp->crp_buf = (caddr_t)&cse->uio;
	crp->crp_callback = (int (*) (struct cryptop *)) cryptodev_cb;
	crp->crp_sid = cse->sid;
	crp->crp_opaque = (void *)cse;

	if (cop->iv) {
		if (crde == NULL) {
			error = EINVAL;
			dprintk("%s no crde\n", __FUNCTION__);
			goto bail;
		}
		if (cse->cipher == CRYPTO_ARC4) { /* XXX use flag? */
			error = EINVAL;
			dprintk("%s arc4 with IV\n", __FUNCTION__);
			goto bail;
		}
		if ((error = copy_from_user(cse->tmp_iv, cop->iv,
						cse->info.blocksize))) {
			dprintk("%s bad iv copy\n", __FUNCTION__);
			goto bail;
		}
		memcpy(crde->crd_iv, cse->tmp_iv, cse->info.blocksize);
		crde->crd_flags |= CRD_F_IV_EXPLICIT | CRD_F_IV_PRESENT;
		crde->crd_skip = 0;
	} else if (cse->cipher == CRYPTO_ARC4) { /* XXX use flag? */
		crde->crd_skip = 0;
	} else if (crde) {
		crde->crd_flags |= CRD_F_IV_PRESENT;
		crde->crd_skip = cse->info.blocksize;
		crde->crd_len -= cse->info.blocksize;
	}

	if (cop->mac) {
		if (crda == NULL) {
			error = EINVAL;
			dprintk("%s no crda\n", __FUNCTION__);
			goto bail;
		}
		crp->crp_mac=cse->tmp_mac;
	}

	/*
	 * Let the dispatch run unlocked, then, interlock against the
	 * callback before checking if the operation completed and going
	 * to sleep.  This insures drivers don't inherit our lock which
	 * results in a lock order reversal between crypto_dispatch forced
	 * entry and the crypto_done callback into us.
	 */
	error = crypto_dispatch(crp);
	if (error == 0) {
		dprintk("%s about to WAIT\n", __FUNCTION__);
		/*
		 * we really need to wait for driver to complete to maintain
		 * state,  luckily interrupts will be remembered
		 */
		do {
			error = wait_event_interruptible(crp->crp_waitq,
					((crp->crp_flags & CRYPTO_F_DONE) != 0));
			error = -error;
		} while ((crp->crp_flags & CRYPTO_F_DONE) == 0);
		dprintk("%s finished WAITING error=%d\n", __FUNCTION__, error);
	}

	if (crp->crp_etype != 0) {
		error = crp->crp_etype;
		dprintk("%s error in crp processing\n", __FUNCTION__);
		goto bail;
	}

	if (cse->error) {
		error = cse->error;
		dprintk("%s error in cse processing\n", __FUNCTION__);
		goto bail;
	}

	if (cop->dst && (error = copy_to_user(cop->dst,
					cse->uio.uio_iov[0].iov_base, cop->len))) {
		dprintk("%s bad dst copy\n", __FUNCTION__);
		goto bail;
	}

	if (cop->mac && (error=copy_to_user(cop->mac, crp->crp_mac,
					cse->info.authsize))) {
		dprintk("%s bad mac copy\n", __FUNCTION__);
		goto bail;
	}

bail:
	if (crp)
		crypto_freereq(crp);
	if (cse->uio.uio_iov[0].iov_base)
		kfree(cse->uio.uio_iov[0].iov_base);

	return (error);
}

static int
cryptodev_cb(void *op)
{
	struct cryptop *crp = (struct cryptop *) op;
	struct csession *cse = (struct csession *)crp->crp_opaque;

	dprintk("%s()\n", __FUNCTION__);
	cse->error = crp->crp_etype;
	if (crp->crp_etype == EAGAIN) {
		crp->crp_flags &= ~CRYPTO_F_DONE;
#ifdef NOTYET
		/*
		 * DAVIDM I am fairly sure that we should turn this into a batch
		 * request to stop bad karma/lockup, revisit
		 */
		crp->crp_flags |= CRYPTO_F_BATCH;
#endif
		return crypto_dispatch(crp);
	}
	wake_up_interruptible(&crp->crp_waitq);
	return (0);
}

static int
cryptodevkey_cb(void *op)
{
	struct cryptkop *krp = (struct cryptkop *) op;
	dprintk("%s()\n", __FUNCTION__);
	wake_up_interruptible(&krp->krp_waitq);
	return (0);
}

static int
cryptodev_key(struct crypt_kop *kop)
{
	struct cryptkop *krp = NULL;
	int error = EINVAL;
	int in, out, size, i;

	dprintk("%s()\n", __FUNCTION__);
	if (kop->crk_iparams + kop->crk_oparams > CRK_MAXPARAM) {
		dprintk("%s params too big\n", __FUNCTION__);
		return (EFBIG);
	}

	in = kop->crk_iparams;
	out = kop->crk_oparams;
	switch (kop->crk_op) {
	case CRK_MOD_EXP:
		if (in == 3 && out == 1)
			break;
		return (EINVAL);
	case CRK_MOD_EXP_CRT:
		if (in == 6 && out == 1)
			break;
		return (EINVAL);
	case CRK_DSA_SIGN:
		if (in == 5 && out == 2)
			break;
		return (EINVAL);
	case CRK_DSA_VERIFY:
		if (in == 7 && out == 0)
			break;
		return (EINVAL);
	case CRK_DH_COMPUTE_KEY:
		if (in == 3 && out == 1)
			break;
		return (EINVAL);
	default:
		return (EINVAL);
	}

	krp = (struct cryptkop *)kmalloc(sizeof *krp, GFP_KERNEL);
	if (!krp)
		return (ENOMEM);
	memset(krp, 0, sizeof *krp);
	krp->krp_op = kop->crk_op;
	krp->krp_status = kop->crk_status;
	krp->krp_iparams = kop->crk_iparams;
	krp->krp_oparams = kop->crk_oparams;
	krp->krp_status = 0;
	krp->krp_callback = (int (*) (struct cryptkop *)) cryptodevkey_cb;
	init_waitqueue_head(&krp->krp_waitq);

	for (i = 0; i < CRK_MAXPARAM; i++)
		krp->krp_param[i].crp_nbits = kop->crk_param[i].crp_nbits;
	for (i = 0; i < krp->krp_iparams + krp->krp_oparams; i++) {
		size = (krp->krp_param[i].crp_nbits + 7) / 8;
		if (size == 0)
			continue;
		krp->krp_param[i].crp_p = (caddr_t) kmalloc(size, GFP_KERNEL);
		if (i >= krp->krp_iparams)
			continue;
		error = copy_from_user(krp->krp_param[i].crp_p,
				kop->crk_param[i].crp_p, size);
		if (error)
			goto fail;
	}

	error = crypto_kdispatch(krp);
	if (error)
		goto fail;

	interruptible_sleep_on(&krp->krp_waitq);
	
	if (krp->krp_status != 0) {
		error = krp->krp_status;
		goto fail;
	}

	for (i = krp->krp_iparams; i < krp->krp_iparams + krp->krp_oparams; i++) {
		size = (krp->krp_param[i].crp_nbits + 7) / 8;
		if (size == 0)
			continue;
		error = copy_to_user(kop->crk_param[i].crp_p, krp->krp_param[i].crp_p,
				size);
		if (error)