path: root/crypto/pcbc.c

/*
 * PCBC: Propagating Cipher Block Chaining mode
 *
 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * Derived from cbc.c
 * - Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 */

#include <crypto/algapi.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>

struct crypto_pcbc_ctx {
	struct crypto_cipher *child;
};

static int crypto_pcbc_setkey(struct crypto_tfm *parent, const u8 *key,
			      unsigned int keylen)
{
	struct crypto_pcbc_ctx *ctx = crypto_tfm_ctx(parent);
	struct crypto_cipher *child = ctx->child;
	int err;

	crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
	crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) &
				CRYPTO_TFM_REQ_MASK);
	err = crypto_cipher_setkey(child, key, keylen);
	crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) &
			     CRYPTO_TFM_RES_MASK);
	return err;
}

static int crypto_pcbc_encrypt_segment(struct blkcipher_desc *desc,
				       struct blkcipher_walk *walk,
				       struct crypto_cipher *tfm)
{
	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
		crypto_cipher_alg(tfm)->cia_encrypt;
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *dst = walk->dst.virt.addr;
	u8 *iv = walk->iv;

	do {
		crypto_xor(iv, src, bsize);
		fn(crypto_cipher_tfm(tfm), dst, iv);
		memcpy(iv, dst, bsize);
		crypto_xor(iv, src, bsize);

		src += bsize;
		dst += bsize;
	} while ((nbytes -= bsize) >= bsize);

	return nbytes;
}

static int crypto_pcbc_encrypt_inplace(struct blkcipher_desc *desc,
				       struct blkcipher_walk *walk,
				       struct crypto_cipher *tfm)
{
	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
		crypto_cipher_alg(tfm)->cia_encrypt;
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *iv = walk->iv;
	u8 tmpbuf[bsize];

	do {
		memcpy(tmpbuf, src, bsize);
		crypto_xor(iv, src, bsize);
		fn(crypto_cipher_tfm(tfm), src, iv);
		memcpy(iv, tmpbuf, bsize);
		crypto_xor(iv, src, bsize);

		src += bsize;
	} while ((nbytes -= bsize) >= bsize);

	memcpy(walk->iv, iv, bsize);

	return nbytes;
}

static int crypto_pcbc_encrypt(struct blkcipher_desc *desc,
			       struct scatterlist *dst, struct scatterlist *src,
			       unsigned int nbytes)
{
	struct blkcipher_walk walk;
	struct crypto_blkcipher *tfm = desc->tfm;
	struct crypto_pcbc_ctx *ctx = crypto_blkcipher_ctx(tfm);
	struct crypto_cipher *child = ctx->child;
	int err;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	while ((nbytes = walk.nbytes)) {
		if (walk.src.virt.addr == walk.dst.virt.addr)
			nbytes = crypto_pcbc_encrypt_inplace(desc, &walk,
							     child);
		else
			nbytes = crypto_pcbc_encrypt_segment(desc, &walk,
							     child);
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	return err;
}

static int crypto_pcbc_decrypt_segment(struct blkcipher_desc *desc,
				       struct blkcipher_walk *walk,
				       struct crypto_cipher *tfm)
{
	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
		crypto_cipher_alg(tfm)->cia_decrypt;
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *dst = walk->dst.virt.addr;
	u8 *iv = walk->iv;

	do {
		fn(crypto_cipher_tfm(tfm), dst, src);
		crypto_xor(dst, iv, bsize);
		memcpy(iv, src, bsize);
		crypto_xor(iv, dst, bsize);

		src += bsize;
		dst += bsize;
	} while ((nbytes -= bsize) >= bsize);

	memcpy(walk->iv, iv, bsize);

	return nbytes;
}

static int crypto_pcbc_decrypt_inplace(struct blkcipher_desc *desc,
				       struct blkcipher_walk *walk,
				       struct crypto_cipher *tfm)
{
	void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
		crypto_cipher_alg(tfm)->cia_decrypt;
	int bsize = crypto_cipher_blocksize(tfm);
	unsigned int nbytes = walk->nbytes;
	u8 *src = walk->src.virt.addr;
	u8 *iv = walk->iv;
	u8 tmpbuf[bsize];

	do {
		memcpy(tmpbuf, src, bsize);
		fn(crypto_cipher_tfm(tfm), src, src);
		crypto_xor(src, iv, bsize);
		memcpy(iv, tmpbuf, bsize);
		crypto_xor(iv, src, bsize);

		src += bsize;
	} while ((nbytes -= bsize) >= bsize);

	memcpy(walk->iv, iv, bsize);

	return nbytes;
}

static int crypto_pcbc_decrypt(struct blkcipher_desc *desc,
			       struct scatterlist *dst, struct scatterlist *src,
			       unsigned int nbytes)
{
	struct blkcipher_walk walk;
	struct crypto_blkcipher *tfm = desc->tfm;
	struct crypto_pcbc_ctx *ctx = crypto_blkcipher_ctx(tfm);
	struct crypto_cipher *child = ctx->child;
	int err;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	err = blkcipher_walk_virt(desc, &walk);

	while ((nbytes = walk.nbytes)) {
		if (walk.src.virt.addr == walk.dst.virt.addr)
			nbytes = crypto_pcbc_decrypt_inplace(desc, &walk,
							     child);
		else
			nbytes = crypto_pcbc_decrypt_segment(desc, &walk,
							     child);
		err = blkcipher_walk_done(desc, &walk, nbytes);
	}

	return err;
}

static int crypto_pcbc_init_tfm(struct crypto_tfm *tfm)
{
	struct crypto_instance *inst = (void *)tfm->__crt_alg;
	struct crypto_spawn *spawn = crypto_instance_ctx(inst);
	struct crypto_pcbc_ctx *ctx = crypto_tfm_ctx(tfm);
	struct crypto_cipher *cipher;

	cipher = crypto_spawn_cipher(spawn);
	if (IS_ERR(cipher))
		return PTR_ERR(cipher);

	ctx->child = cipher;
	return 0;
}

static void crypto_pcbc_exit_tfm(struct crypto_tfm *tfm)
{
	struct crypto_pcbc_ctx *ctx = crypto_tfm_ctx(tfm);
	crypto_free_cipher(ctx->child);
}

static struct crypto_instance *crypto_pcbc_alloc(struct rtattr **tb)
{
	struct crypto_instance *inst;
	struct crypto_alg *alg;
	int err;

	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER);
	if (err)
		return ERR_PTR(err);

	alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
				  CRYPTO_ALG_TYPE_MASK);
	if (IS_ERR(alg))
		return ERR_PTR(PTR_ERR(alg));

	inst = crypto_alloc_instance("pcbc", alg);
	if (IS_ERR(inst))
		goto out_put_alg;

	inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
	inst->alg.cra_priority = alg->cra_priority;
	inst->alg.cra_blocksize = alg->cra_blocksize;
	inst->alg.cra_alignmask = alg->cra_alignmask;
	inst->alg.cra_type = &crypto_blkcipher_type;

	/* We access the data as u32s when xoring. */
	inst->alg.cra_alignmask |= __alignof__(u32) - 1;
an>keys():
				print PF_WJOINT
				if event['handle'] == "kfree_skb":
					print PF_KFREE_SKB % \
						(diff_msec(base_t,
						event['comm_t']),
						event['location'])
				elif event['handle'] == "consume_skb":
					print PF_CONS_SKB % \
						diff_msec(base_t,
							event['comm_t'])
			print PF_JOINT

def trace_begin():
	global show_tx
	global show_rx
	global dev
	global debug

	for i in range(len(sys.argv)):
		if i == 0:
			continue
		arg = sys.argv[i]
		if arg == 'tx':
			show_tx = 1
		elif arg =='rx':
			show_rx = 1
		elif arg.find('dev=',0, 4) >= 0:
			dev = arg[4:]
		elif arg == 'debug':
			debug = 1
	if show_tx == 0  and show_rx == 0:
		show_tx = 1
		show_rx = 1

def trace_end():
	# order all events in time
	all_event_list.sort(lambda a,b :cmp(a[EINFO_IDX_TIME],
					    b[EINFO_IDX_TIME]))
	# process all events
	for i in range(len(all_event_list)):
		event_info = all_event_list[i]
		name = event_info[EINFO_IDX_NAME]
		if name == 'irq__softirq_exit':
			handle_irq_softirq_exit(event_info)
		elif name == 'irq__softirq_entry':
			handle_irq_softirq_entry(event_info)
		elif name == 'irq__softirq_raise':
			handle_irq_softirq_raise(event_info)
		elif name == 'irq__irq_handler_entry':
			handle_irq_handler_entry(event_info)
		elif name == 'irq__irq_handler_exit':
			handle_irq_handler_exit(event_info)
		elif name == 'napi__napi_poll':
			handle_napi_poll(event_info)
		elif name == 'net__netif_receive_skb':
			handle_netif_receive_skb(event_info)
		elif name == 'net__netif_rx':
			handle_netif_rx(event_info)
		elif name == 'skb__skb_copy_datagram_iovec':
			handle_skb_copy_datagram_iovec(event_info)
		elif name == 'net__net_dev_queue':
			handle_net_dev_queue(event_info)
		elif name == 'net__net_dev_xmit':
			handle_net_dev_xmit(event_info)
		elif name == 'skb__kfree_skb':
			handle_kfree_skb(event_info)
		elif name == 'skb__consume_skb':
			handle_consume_skb(event_info)
	# display receive hunks
	if show_rx:
		for i in range(len(receive_hunk_list)):
			print_receive(receive_hunk_list[i])
	# display transmit hunks
	if show_tx:
		print "   dev    len      Qdisc        " \
			"       netdevice             free"
		for i in range(len(tx_free_list)):
			print_transmit(tx_free_list[i])
	if debug:
		print "debug buffer status"
		print "----------------------------"
		print "xmit Qdisc:remain:%d overflow:%d" % \
			(len(tx_queue_list), of_count_tx_queue_list)
		print "xmit netdevice:remain:%d overflow:%d" % \
			(len(tx_xmit_list), of_count_tx_xmit_list)
		print "receive:remain:%d overflow:%d" % \
			(len(rx_skb_list), of_count_rx_skb_list)

# called from perf, when it finds a correspoinding event
def irq__softirq_entry(name, context, cpu, sec, nsec, pid, comm, vec):
	if symbol_str("irq__softirq_entry", "vec", vec) != "NET_RX":
		return
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm, vec)
	all_event_list.append(event_info)

def irq__softirq_exit(name, context, cpu, sec, nsec, pid, comm, vec):
	if symbol_str("irq__softirq_entry", "vec", vec) != "NET_RX":
		return
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm, vec)
	all_event_list.append(event_info)

def irq__softirq_raise(name, context, cpu, sec, nsec, pid, comm, vec):
	if symbol_str("irq__softirq_entry", "vec", vec) != "NET_RX":
		return
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm, vec)
	all_event_list.append(event_info)

def irq__irq_handler_entry(name, context, cpu, sec, nsec, pid, comm,
			irq, irq_name):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			irq, irq_name)
	all_event_list.append(event_info)

def irq__irq_handler_exit(name, context, cpu, sec, nsec, pid, comm, irq, ret):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm, irq, ret)
	all_event_list.append(event_info)

def napi__napi_poll(name, context, cpu, sec, nsec, pid, comm, napi, dev_name):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			napi, dev_name)
	all_event_list.append(event_info)

def net__netif_receive_skb(name, context, cpu, sec, nsec, pid, comm, skbaddr,
			skblen, dev_name):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			skbaddr, skblen, dev_name)
	all_event_list.append(event_info)

def net__netif_rx(name, context, cpu, sec, nsec, pid, comm, skbaddr,
			skblen, dev_name):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			skbaddr, skblen, dev_name)
	all_event_list.append(event_info)

def net__net_dev_queue(name, context, cpu, sec, nsec, pid, comm,
			skbaddr, skblen, dev_name):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			skbaddr, skblen, dev_name)
	all_event_list.append(event_info)

def net__net_dev_xmit(name, context, cpu, sec, nsec, pid, comm,
			skbaddr, skblen, rc, dev_name):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			skbaddr, skblen, rc ,dev_name)
	all_event_list.append(event_info)

def skb__kfree_skb(name, context, cpu, sec, nsec, pid, comm,
			skbaddr, protocol, location):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			skbaddr, protocol, location)
	all_event_list.append(event_info)

def skb__consume_skb(name, context, cpu, sec, nsec, pid, comm, skbaddr):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			skbaddr)
	all_event_list.append(event_info)

def skb__skb_copy_datagram_iovec(name, context, cpu, sec, nsec, pid, comm,
	skbaddr, skblen):
	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
			skbaddr, skblen)
	all_event_list.append(event_info)

def handle_irq_handler_entry(event_info):
	(name, context, cpu, time, pid, comm, irq, irq_name) = event_info
	if cpu not in irq_dic.keys():
		irq_dic[cpu] = []
	irq_record = {'irq':irq, 'name':irq_name, 'cpu':cpu, 'irq_ent_t':time}
	irq_dic[cpu].append(irq_record)

def handle_irq_handler_exit(event_info):
	(name, context, cpu, time, pid, comm, irq, ret) = event_info
	if cpu not in irq_dic.keys():
		return
	irq_record = irq_dic[cpu].pop()
	if irq != irq_record['irq']:
		return
	irq_record.update({'irq_ext_t':time})
	# if an irq doesn't include NET_RX softirq, drop.
	if 'event_list' in irq_record.keys():
		irq_dic[cpu].append(irq_record)

def handle_irq_softirq_raise(event_info):
	(name, context, cpu, time, pid, comm, vec) = event_info
	if cpu not in irq_dic.keys() \
	or len(irq_dic[cpu]) == 0:
		return
	irq_record = irq_dic[cpu].pop()
	if 'event_list' in irq_record.keys():
		irq_event_list = irq_record['event_list']
	else:
		irq_event_list = []
	irq_event_list.append({'time':time, 'event':'sirq_raise'})
	irq_record.update({'event_list':irq_event_list})
	irq_dic[cpu].append(irq_record)

def handle_irq_softirq_entry(event_info):
	(name, context, cpu, time, pid, comm, vec) = event_info
	net_rx_dic[cpu] = {'sirq_ent_t':time, 'event_list':[]}

def handle_irq_softirq_exit(event_info):
	(name, context, cpu, time, pid, comm, vec) = event_info
	irq_list = []
	event_list = 0
	if cpu in irq_dic.keys():
		irq_list = irq_dic[cpu]
		del irq_dic[cpu]
	if cpu in net_rx_dic.keys():
		sirq_ent_t = net_rx_dic[cpu]['sirq_ent_t']
		event_list = net_rx_dic[cpu]['event_list']
		del net_rx_dic[cpu]
	if irq_list == [] or event_list == 0:
		return
	rec_data = {'sirq_ent_t':sirq_ent_t, 'sirq_ext_t':time,
		    'irq_list':irq_list, 'event_list':event_list}
	# merge information realted to a NET_RX softirq
	receive_hunk_list.append(rec_data)

def handle_napi_poll(event_info):
	(name, context, cpu, time, pid, comm, napi, dev_name) = event_info
	if cpu in net_rx_dic.keys():
		event_list = net_rx_dic[cpu]['event_list']
		rec_data = {'event_name':'napi_poll',
				'dev':dev_name, 'event_t':time}
		event_list.append(rec_data)

def handle_netif_rx(event_info):
	(name, context, cpu, time, pid, comm,
		skbaddr, skblen, dev_name) = event_info
	if cpu not in irq_dic.keys() \
	or len(irq_dic[cpu]) == 0:
		return
	irq_record = irq_dic[cpu].pop()
	if 'event_list' in irq_record.keys():
		irq_event_list = irq_record['event_list']
	else:
		irq_event_list = []
	irq_event_list.append({'time':time, 'event':'netif_rx',
		'skbaddr':skbaddr, 'skblen':skblen, 'dev_name':dev_name})
	irq_record.update({'event_list':irq_event_list})
	irq_dic[cpu].append(irq_record)

def handle_netif_receive_skb(event_info):
	global of_count_rx_skb_list

	(name, context, cpu, time, pid, comm,
		skbaddr, skblen, dev_name) = event_info
	if cpu in net_rx_dic.keys():
		rec_data = {'event_name':'netif_receive_skb',
			    'event_t':time, 'skbaddr':skbaddr, 'len':skblen}
		event_list = net_rx_dic[cpu]['event_list']
		event_list.append(rec_data)
		rx_skb_list.insert(0, rec_data)
		if len(rx_skb_list) > buffer_budget:
			rx_skb_list.pop()
			of_count_rx_skb_list += 1

def handle_net_dev_queue(event_info):
	global of_count_tx_queue_list

	(name, context, cpu, time, pid, comm,
		skbaddr, skblen, dev_name) = event_info
	skb = {'dev':dev_name, 'skbaddr':skbaddr, 'len':skblen, 'queue_t':time}
	tx_queue_list.insert(0, skb)
	if len(tx_queue_list) > buffer_budget:
		tx_queue_list.pop()
		of_count_tx_queue_list += 1

def handle_net_dev_xmit(event_info):
	global of_count_tx_xmit_list

	(name, context, cpu, time, pid, comm,
		skbaddr, skblen, rc, dev_name) = event_info
	if rc == 0: # NETDEV_TX_OK
		for i in range(len(tx_queue_list)):
			skb = tx_queue_list[i]
			if skb['skbaddr'] == skbaddr:
				skb['xmit_t'] = time
				tx_xmit_list.insert(0, skb)
				del tx_queue_list[i]
				if len(tx_xmit_list) > buffer_budget:
					tx_xmit_list.pop()
					of_count_tx_xmit_list += 1
				return

def handle_kfree_skb(event_info):
	(name, context, cpu, time, pid, comm,
		skbaddr, protocol, location) = event_info
	for i in range(len(tx_queue_list)):
		skb = tx_queue_list[i]
		if skb['skbaddr'] == skbaddr:
			del tx_queue_list[i]
			return
	for i in range(len(tx_xmit_list)):
		skb = tx_xmit_list[i]
		if skb['skbaddr'] == skbaddr:
			skb['free_t'] = time
			tx_free_list.append(skb)
			del tx_xmit_list[i]
			return
	for i in range(len(rx_skb_list)):
		rec_data = rx_skb_list[i]
		if rec_data['skbaddr'] == skbaddr:
			rec_data.update({'handle':"kfree_skb",
					'comm':comm, 'pid':pid, 'comm_t':time})
			del rx_skb_list[i]
			return

def handle_consume_skb(event_info):
	(name, context, cpu, time, pid, comm, skbaddr) = event_info
	for i in range(len(tx_xmit_list)):
		skb = tx_xmit_list[i]
		if skb['skbaddr'] == skbaddr:
			skb['free_t'] = time
			tx_free_list.append(skb)
			del tx_xmit_list[i]
			return

def handle_skb_copy_datagram_iovec(event_info):
	(name, context, cpu, time, pid, comm, skbaddr, skblen) = event_info
	for i in range(len(rx_skb_list)):
		rec_data = rx_skb_list[i]
		if skbaddr == rec_data['skbaddr']:
			rec_data.update({'handle':"skb_copy_datagram_iovec",
					'comm':comm, 'pid':pid, 'comm_t':time})
			del rx_skb_list[i]
			return