cryptocop.c

linux内核源码

				current_out_cdesc->next = ed;
				current_out_cdesc = ed;
			} else {
				/* Set EOP in the current out descriptor since the only active module is
				 * the one needing the EOP. */

				current_out_cdesc->dma_descr->out_eop = 1;
			}
		}

		if (cipher_ctx.done && cipher_ctx.active) cipher_ctx.active = 0;
		if (digest_ctx.done && digest_ctx.active) digest_ctx.active = 0;
		if (csum_ctx.done && csum_ctx.active) csum_ctx.active = 0;
		indata_ix += odsc->length;
		odsc = odsc->next;
	} /* while (odsc) */ /* Process descriptors. */
	DEBUG(printk("cryptocop_setup_dma_list: done parsing operation descriptors\n"));
	if (cipher_ctx.tcfg && (cipher_ctx.active || !cipher_ctx.done)){
		DEBUG_API(printk("cryptocop_setup_dma_list: cipher operation not terminated.\n"));
		failed = -EINVAL;
		goto error_cleanup;
	}
	if (digest_ctx.tcfg && (digest_ctx.active || !digest_ctx.done)){
		DEBUG_API(printk("cryptocop_setup_dma_list: digest operation not terminated.\n"));
		failed = -EINVAL;
		goto error_cleanup;
	}
	if (csum_ctx.tcfg && (csum_ctx.active || !csum_ctx.done)){
		DEBUG_API(printk("cryptocop_setup_dma_list: csum operation not terminated.\n"));
		failed = -EINVAL;
		goto error_cleanup;
	}

	failed = append_input_descriptors(operation, &current_in_cdesc, &current_out_cdesc, &cipher_ctx, alloc_flag);
	if (failed){
		DEBUG_API(printk("cryptocop_setup_dma_list: append_input_descriptors cipher_ctx %d\n", failed));
		goto error_cleanup;
	}
	failed = append_input_descriptors(operation, &current_in_cdesc, &current_out_cdesc, &digest_ctx, alloc_flag);
	if (failed){
		DEBUG_API(printk("cryptocop_setup_dma_list: append_input_descriptors cipher_ctx %d\n", failed));
		goto error_cleanup;
	}
	failed = append_input_descriptors(operation, &current_in_cdesc, &current_out_cdesc, &csum_ctx, alloc_flag);
	if (failed){
		DEBUG_API(printk("cryptocop_setup_dma_list: append_input_descriptors cipher_ctx %d\n", failed));
		goto error_cleanup;
	}

	DEBUG(printk("cryptocop_setup_dma_list: int_op=0x%p, *int_op=0x%p\n", int_op, *int_op));
	(*int_op)->cdesc_out = out_cdesc_head.next;
	(*int_op)->cdesc_in = in_cdesc_head.next;
	DEBUG(printk("cryptocop_setup_dma_list: out_cdesc_head=0x%p in_cdesc_head=0x%p\n", (*int_op)->cdesc_out, (*int_op)->cdesc_in));

	setup_descr_chain(out_cdesc_head.next);
	setup_descr_chain(in_cdesc_head.next);

	/* Last but not least: mark the last DMA in descriptor for a INTR and EOL and the the
	 * last DMA out descriptor for EOL.
	 */
	current_in_cdesc->dma_descr->intr = 1;
	current_in_cdesc->dma_descr->eol = 1;
	current_out_cdesc->dma_descr->eol = 1;

	/* Setup DMA contexts. */
	(*int_op)->ctx_out.next = NULL;
	(*int_op)->ctx_out.eol = 1;
	(*int_op)->ctx_out.intr = 0;
	(*int_op)->ctx_out.store_mode = 0;
	(*int_op)->ctx_out.en = 0;
	(*int_op)->ctx_out.dis = 0;
	(*int_op)->ctx_out.md0 = 0;
	(*int_op)->ctx_out.md1 = 0;
	(*int_op)->ctx_out.md2 = 0;
	(*int_op)->ctx_out.md3 = 0;
	(*int_op)->ctx_out.md4 = 0;
	(*int_op)->ctx_out.saved_data = (dma_descr_data*)virt_to_phys((*int_op)->cdesc_out->dma_descr);
	(*int_op)->ctx_out.saved_data_buf = (*int_op)->cdesc_out->dma_descr->buf; /* Already physical address. */

	(*int_op)->ctx_in.next = NULL;
	(*int_op)->ctx_in.eol = 1;
	(*int_op)->ctx_in.intr = 0;
	(*int_op)->ctx_in.store_mode = 0;
	(*int_op)->ctx_in.en = 0;
	(*int_op)->ctx_in.dis = 0;
	(*int_op)->ctx_in.md0 = 0;
	(*int_op)->ctx_in.md1 = 0;
	(*int_op)->ctx_in.md2 = 0;
	(*int_op)->ctx_in.md3 = 0;
	(*int_op)->ctx_in.md4 = 0;

	(*int_op)->ctx_in.saved_data = (dma_descr_data*)virt_to_phys((*int_op)->cdesc_in->dma_descr);
	(*int_op)->ctx_in.saved_data_buf = (*int_op)->cdesc_in->dma_descr->buf; /* Already physical address. */

	DEBUG(printk("cryptocop_setup_dma_list: done\n"));
	return 0;

error_cleanup:
	{
		/* Free all allocated resources. */
		struct cryptocop_dma_desc *tmp_cdesc;
		while (digest_ctx.pad_descs){
			tmp_cdesc = digest_ctx.pad_descs->next;
			free_cdesc(digest_ctx.pad_descs);
			digest_ctx.pad_descs = tmp_cdesc;
		}
		while (csum_ctx.pad_descs){
			tmp_cdesc = csum_ctx.pad_descs->next;
			free_cdesc(csum_ctx.pad_descs);
			csum_ctx.pad_descs = tmp_cdesc;
		}
		assert(cipher_ctx.pad_descs == NULL); /* The ciphers are never padded. */

		if (*int_op != NULL) delete_internal_operation(*int_op);
	}
	DEBUG_API(printk("cryptocop_setup_dma_list: done with error %d\n", failed));
	return failed;
}


static void delete_internal_operation(struct cryptocop_int_operation *iop)
{
	void                      *ptr = iop->alloc_ptr;
	struct cryptocop_dma_desc *cd = iop->cdesc_out;
	struct cryptocop_dma_desc *next;

	DEBUG(printk("delete_internal_operation: iop=0x%p, alloc_ptr=0x%p\n", iop, ptr));

	while (cd) {
		next = cd->next;
		free_cdesc(cd);
		cd = next;
	}
	cd = iop->cdesc_in;
	while (cd) {
		next = cd->next;
		free_cdesc(cd);
		cd = next;
	}
	kfree(ptr);
}

#define MD5_MIN_PAD_LENGTH (9)
#define MD5_PAD_LENGTH_FIELD_LENGTH (8)

static int create_md5_pad(int alloc_flag, unsigned long long hashed_length, char **pad, size_t *pad_length)
{
	size_t                  padlen = MD5_BLOCK_LENGTH - (hashed_length % MD5_BLOCK_LENGTH);
	unsigned char           *p;
	int                     i;
	unsigned long long int  bit_length = hashed_length << 3;

	if (padlen < MD5_MIN_PAD_LENGTH) padlen += MD5_BLOCK_LENGTH;

	p = kmalloc(padlen, alloc_flag);
	if (!pad) return -ENOMEM;

	*p = 0x80;
	memset(p+1, 0, padlen - 1);

	DEBUG(printk("create_md5_pad: hashed_length=%lld bits == %lld bytes\n", bit_length, hashed_length));

	i = padlen - MD5_PAD_LENGTH_FIELD_LENGTH;
	while (bit_length != 0){
		p[i++] = bit_length % 0x100;
		bit_length >>= 8;
	}

	*pad = (char*)p;
	*pad_length = padlen;

	return 0;
}

#define SHA1_MIN_PAD_LENGTH (9)
#define SHA1_PAD_LENGTH_FIELD_LENGTH (8)

static int create_sha1_pad(int alloc_flag, unsigned long long hashed_length, char **pad, size_t *pad_length)
{
	size_t                  padlen = SHA1_BLOCK_LENGTH - (hashed_length % SHA1_BLOCK_LENGTH);
	unsigned char           *p;
	int                     i;
	unsigned long long int  bit_length = hashed_length << 3;

	if (padlen < SHA1_MIN_PAD_LENGTH) padlen += SHA1_BLOCK_LENGTH;

	p = kmalloc(padlen, alloc_flag);
	if (!pad) return -ENOMEM;

	*p = 0x80;
	memset(p+1, 0, padlen - 1);

	DEBUG(printk("create_sha1_pad: hashed_length=%lld bits == %lld bytes\n", bit_length, hashed_length));

	i = padlen - 1;
	while (bit_length != 0){
		p[i--] = bit_length % 0x100;
		bit_length >>= 8;
	}

	*pad = (char*)p;
	*pad_length = padlen;

	return 0;
}


static int transform_ok(struct cryptocop_transform_init *tinit)
{
	switch (tinit->alg){
	case cryptocop_alg_csum:
		switch (tinit->csum_mode){
		case cryptocop_csum_le:
		case cryptocop_csum_be:
			break;
		default:
			DEBUG_API(printk("transform_ok: Bad mode set for csum transform\n"));
			return -EINVAL;
		}
	case cryptocop_alg_mem2mem:
	case cryptocop_alg_md5:
	case cryptocop_alg_sha1:
		if (tinit->keylen != 0) {
			DEBUG_API(printk("transform_ok: non-zero keylength, %d, for a digest/csum algorithm\n", tinit->keylen));
			return -EINVAL; /* This check is a bit strict. */
		}
		break;
	case cryptocop_alg_des:
		if (tinit->keylen != 64) {
			DEBUG_API(printk("transform_ok: keylen %d invalid for DES\n", tinit->keylen));
			return -EINVAL;
		}
		break;
	case cryptocop_alg_3des:
		if (tinit->keylen != 192) {
			DEBUG_API(printk("transform_ok: keylen %d invalid for 3DES\n", tinit->keylen));
			return -EINVAL;
		}
		break;
	case cryptocop_alg_aes:
		if (tinit->keylen != 128 && tinit->keylen != 192 && tinit->keylen != 256) {
			DEBUG_API(printk("transform_ok: keylen %d invalid for AES\n", tinit->keylen));
			return -EINVAL;
		}
		break;
	case cryptocop_no_alg:
	default:
		DEBUG_API(printk("transform_ok: no such algorithm %d\n", tinit->alg));
		return -EINVAL;
	}

	switch (tinit->alg){
	case cryptocop_alg_des:
	case cryptocop_alg_3des:
	case cryptocop_alg_aes:
		if (tinit->cipher_mode != cryptocop_cipher_mode_ecb && tinit->cipher_mode != cryptocop_cipher_mode_cbc) return -EINVAL;
	default:
		 break;
	}
	return 0;
}


int cryptocop_new_session(cryptocop_session_id *sid, struct cryptocop_transform_init *tinit, int alloc_flag)
{
	struct cryptocop_session         *sess;
	struct cryptocop_transform_init  *tfrm_in = tinit;
	struct cryptocop_transform_init  *tmp_in;
	int                              no_tfrms = 0;
	int                              i;
	unsigned long int                flags;

	init_stream_coprocessor(); /* For safety if we are called early */

	while (tfrm_in){
		int err;
		++no_tfrms;
		if ((err = transform_ok(tfrm_in))) {
			DEBUG_API(printk("cryptocop_new_session, bad transform\n"));
			return err;
		}
		tfrm_in = tfrm_in->next;
	}
	if (0 == no_tfrms) {
		DEBUG_API(printk("cryptocop_new_session, no transforms specified\n"));
		return -EINVAL;
	}

	sess = kmalloc(sizeof(struct cryptocop_session), alloc_flag);
	if (!sess){
		DEBUG_API(printk("cryptocop_new_session, kmalloc cryptocop_session\n"));
		return -ENOMEM;
	}

	sess->tfrm_ctx = kmalloc(no_tfrms * sizeof(struct cryptocop_transform_ctx), alloc_flag);
	if (!sess->tfrm_ctx) {
		DEBUG_API(printk("cryptocop_new_session, kmalloc cryptocop_transform_ctx\n"));
		kfree(sess);
		return -ENOMEM;
	}

	tfrm_in = tinit;
	for (i = 0; i < no_tfrms; i++){
		tmp_in = tfrm_in->next;
		while (tmp_in){
			if (tmp_in->tid == tfrm_in->tid) {
				DEBUG_API(printk("cryptocop_new_session, duplicate transform ids\n"));
				kfree(sess->tfrm_ctx);
				kfree(sess);
				return -EINVAL;
			}
			tmp_in = tmp_in->next;
		}
		memcpy(&sess->tfrm_ctx[i].init, tfrm_in, sizeof(struct cryptocop_transform_init));
		sess->tfrm_ctx[i].dec_key_set = 0;
		sess->tfrm_ctx[i].next = &sess->tfrm_ctx[i] + 1;

		tfrm_in = tfrm_in->next;
	}
	sess->tfrm_ctx[i-1].next = NULL;

	spin_lock_irqsave(&cryptocop_sessions_lock, flags);
	sess->sid = next_sid;
	next_sid++;
	/* TODO If we are really paranoid we should do duplicate check to handle sid wraparound.
	 *      OTOH 2^64 is a really large number of session. */
	if (next_sid == 0) next_sid = 1;

	/* Prepend to session list. */
	sess->next = cryptocop_sessions;
	cryptocop_sessions = sess;
	spin_unlock_irqrestore(&cryptocop_sessions_lock, flags);
	*sid = sess->sid;
	return 0;
}


int cryptocop_free_session(cryptocop_session_id sid)
{
	struct cryptocop_transform_ctx    *tc;
	struct cryptocop_session          *sess = NULL;
	struct cryptocop_session          *psess = NULL;
	unsigned long int                 flags;
	int                               i;
	LIST_HEAD(remove_list);
	struct list_head                  *node, *tmp;
	struct cryptocop_prio_job         *pj;

	DEBUG(printk("cryptocop_free_session: sid=%lld\n", sid));

	spin_lock_irqsave(&cryptocop_sessions_lock, flags);
	sess = cryptocop_sessions;
	while (sess && sess->sid != sid){
		psess = sess;
		sess = sess->next;
	}
	if (sess){
		if (psess){
			psess->next = sess->next;
		} else {
			cryptocop_sessions = sess->next;
		}
	}
	spin_unlock_irqrestore(&cryptocop_sessions_lock, flags);

	if (!sess) return -EINVAL;

	/* Remove queued jobs. */
	spin_lock_irqsave(&cryptocop_job_queue_lock, flags);

	for (i = 0; i < cryptocop_prio_no_prios; i++){
		if (!list_empty(&(cryptocop_job_queues[i].jobs))){
			list_for_each_safe(node, tmp, &(cryptocop_job_queues[i].jobs)) {
				pj = list_entry(node, struct cryptocop_prio_job, node);
				if (pj->oper->sid == sid) {
					list_move_tail(node, &remove_list);
				}
			}
		}
	}
	spin_unlock_irqrestore(&cryptocop_job_queue_lock, flags);

	list_for_each_safe(node, tmp, &remove_list) {
		list_del(node);
		pj = list_entry(node, struct cryptocop_prio_job, node);
		pj->oper->operation_status = -EAGAIN;  /* EAGAIN is not ideal for job/session terminated but it's the best choice I know of. */
		DEBUG(printk("cryptocop_free_session: pj=0x%p, pj->oper=0x%p, pj->iop=0x%p\n", pj, pj->oper, pj->iop));
		pj->oper->cb(pj->oper, pj->oper->cb_data);
		delete_internal_operation(pj->iop);
		kfree(pj);
	}

	tc = sess->tfrm_ctx;
	/* Erase keying data. */
	while (tc){
		DEBUG(printk("cryptocop_free_session: memset keys, tfrm id=%d\n", tc->init.tid));
		memset(tc->init.key, 0xff, CRYPTOCOP_MAX_KEY_LENGTH);
		memset(tc->dec_key, 0xff, CRYPTOCOP_MAX_KEY_LENGTH);
		tc = tc->next;
	}
	kfree(sess->tfrm_ctx);
	kfree(sess);

	return 0;
}

static struct cryptocop_session *get_session(cryptocop_session_id sid)
{
	struct cryptocop_session    *sess;
	unsigned long int           flags;