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-rw-r--r--kernel/net/mac802154/llsec.c1056
1 files changed, 1056 insertions, 0 deletions
diff --git a/kernel/net/mac802154/llsec.c b/kernel/net/mac802154/llsec.c
new file mode 100644
index 000000000..5b2be1283
--- /dev/null
+++ b/kernel/net/mac802154/llsec.c
@@ -0,0 +1,1056 @@
+/*
+ * Copyright (C) 2014 Fraunhofer ITWM
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Written by:
+ * Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
+ */
+
+#include <linux/err.h>
+#include <linux/bug.h>
+#include <linux/completion.h>
+#include <linux/ieee802154.h>
+#include <crypto/algapi.h>
+
+#include "ieee802154_i.h"
+#include "llsec.h"
+
+static void llsec_key_put(struct mac802154_llsec_key *key);
+static bool llsec_key_id_equal(const struct ieee802154_llsec_key_id *a,
+ const struct ieee802154_llsec_key_id *b);
+
+static void llsec_dev_free(struct mac802154_llsec_device *dev);
+
+void mac802154_llsec_init(struct mac802154_llsec *sec)
+{
+ memset(sec, 0, sizeof(*sec));
+
+ memset(&sec->params.default_key_source, 0xFF, IEEE802154_ADDR_LEN);
+
+ INIT_LIST_HEAD(&sec->table.security_levels);
+ INIT_LIST_HEAD(&sec->table.devices);
+ INIT_LIST_HEAD(&sec->table.keys);
+ hash_init(sec->devices_short);
+ hash_init(sec->devices_hw);
+ rwlock_init(&sec->lock);
+}
+
+void mac802154_llsec_destroy(struct mac802154_llsec *sec)
+{
+ struct ieee802154_llsec_seclevel *sl, *sn;
+ struct ieee802154_llsec_device *dev, *dn;
+ struct ieee802154_llsec_key_entry *key, *kn;
+
+ list_for_each_entry_safe(sl, sn, &sec->table.security_levels, list) {
+ struct mac802154_llsec_seclevel *msl;
+
+ msl = container_of(sl, struct mac802154_llsec_seclevel, level);
+ list_del(&sl->list);
+ kfree(msl);
+ }
+
+ list_for_each_entry_safe(dev, dn, &sec->table.devices, list) {
+ struct mac802154_llsec_device *mdev;
+
+ mdev = container_of(dev, struct mac802154_llsec_device, dev);
+ list_del(&dev->list);
+ llsec_dev_free(mdev);
+ }
+
+ list_for_each_entry_safe(key, kn, &sec->table.keys, list) {
+ struct mac802154_llsec_key *mkey;
+
+ mkey = container_of(key->key, struct mac802154_llsec_key, key);
+ list_del(&key->list);
+ llsec_key_put(mkey);
+ kfree(key);
+ }
+}
+
+int mac802154_llsec_get_params(struct mac802154_llsec *sec,
+ struct ieee802154_llsec_params *params)
+{
+ read_lock_bh(&sec->lock);
+ *params = sec->params;
+ read_unlock_bh(&sec->lock);
+
+ return 0;
+}
+
+int mac802154_llsec_set_params(struct mac802154_llsec *sec,
+ const struct ieee802154_llsec_params *params,
+ int changed)
+{
+ write_lock_bh(&sec->lock);
+
+ if (changed & IEEE802154_LLSEC_PARAM_ENABLED)
+ sec->params.enabled = params->enabled;
+ if (changed & IEEE802154_LLSEC_PARAM_FRAME_COUNTER)
+ sec->params.frame_counter = params->frame_counter;
+ if (changed & IEEE802154_LLSEC_PARAM_OUT_LEVEL)
+ sec->params.out_level = params->out_level;
+ if (changed & IEEE802154_LLSEC_PARAM_OUT_KEY)
+ sec->params.out_key = params->out_key;
+ if (changed & IEEE802154_LLSEC_PARAM_KEY_SOURCE)
+ sec->params.default_key_source = params->default_key_source;
+ if (changed & IEEE802154_LLSEC_PARAM_PAN_ID)
+ sec->params.pan_id = params->pan_id;
+ if (changed & IEEE802154_LLSEC_PARAM_HWADDR)
+ sec->params.hwaddr = params->hwaddr;
+ if (changed & IEEE802154_LLSEC_PARAM_COORD_HWADDR)
+ sec->params.coord_hwaddr = params->coord_hwaddr;
+ if (changed & IEEE802154_LLSEC_PARAM_COORD_SHORTADDR)
+ sec->params.coord_shortaddr = params->coord_shortaddr;
+
+ write_unlock_bh(&sec->lock);
+
+ return 0;
+}
+
+static struct mac802154_llsec_key*
+llsec_key_alloc(const struct ieee802154_llsec_key *template)
+{
+ const int authsizes[3] = { 4, 8, 16 };
+ struct mac802154_llsec_key *key;
+ int i;
+
+ key = kzalloc(sizeof(*key), GFP_KERNEL);
+ if (!key)
+ return NULL;
+
+ kref_init(&key->ref);
+ key->key = *template;
+
+ BUILD_BUG_ON(ARRAY_SIZE(authsizes) != ARRAY_SIZE(key->tfm));
+
+ for (i = 0; i < ARRAY_SIZE(key->tfm); i++) {
+ key->tfm[i] = crypto_alloc_aead("ccm(aes)", 0,
+ CRYPTO_ALG_ASYNC);
+ if (IS_ERR(key->tfm[i]))
+ goto err_tfm;
+ if (crypto_aead_setkey(key->tfm[i], template->key,
+ IEEE802154_LLSEC_KEY_SIZE))
+ goto err_tfm;
+ if (crypto_aead_setauthsize(key->tfm[i], authsizes[i]))
+ goto err_tfm;
+ }
+
+ key->tfm0 = crypto_alloc_blkcipher("ctr(aes)", 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(key->tfm0))
+ goto err_tfm;
+
+ if (crypto_blkcipher_setkey(key->tfm0, template->key,
+ IEEE802154_LLSEC_KEY_SIZE))
+ goto err_tfm0;
+
+ return key;
+
+err_tfm0:
+ crypto_free_blkcipher(key->tfm0);
+err_tfm:
+ for (i = 0; i < ARRAY_SIZE(key->tfm); i++)
+ if (key->tfm[i])
+ crypto_free_aead(key->tfm[i]);
+
+ kfree(key);
+ return NULL;
+}
+
+static void llsec_key_release(struct kref *ref)
+{
+ struct mac802154_llsec_key *key;
+ int i;
+
+ key = container_of(ref, struct mac802154_llsec_key, ref);
+
+ for (i = 0; i < ARRAY_SIZE(key->tfm); i++)
+ crypto_free_aead(key->tfm[i]);
+
+ crypto_free_blkcipher(key->tfm0);
+ kfree(key);
+}
+
+static struct mac802154_llsec_key*
+llsec_key_get(struct mac802154_llsec_key *key)
+{
+ kref_get(&key->ref);
+ return key;
+}
+
+static void llsec_key_put(struct mac802154_llsec_key *key)
+{
+ kref_put(&key->ref, llsec_key_release);
+}
+
+static bool llsec_key_id_equal(const struct ieee802154_llsec_key_id *a,
+ const struct ieee802154_llsec_key_id *b)
+{
+ if (a->mode != b->mode)
+ return false;
+
+ if (a->mode == IEEE802154_SCF_KEY_IMPLICIT)
+ return ieee802154_addr_equal(&a->device_addr, &b->device_addr);
+
+ if (a->id != b->id)
+ return false;
+
+ switch (a->mode) {
+ case IEEE802154_SCF_KEY_INDEX:
+ return true;
+ case IEEE802154_SCF_KEY_SHORT_INDEX:
+ return a->short_source == b->short_source;
+ case IEEE802154_SCF_KEY_HW_INDEX:
+ return a->extended_source == b->extended_source;
+ }
+
+ return false;
+}
+
+int mac802154_llsec_key_add(struct mac802154_llsec *sec,
+ const struct ieee802154_llsec_key_id *id,
+ const struct ieee802154_llsec_key *key)
+{
+ struct mac802154_llsec_key *mkey = NULL;
+ struct ieee802154_llsec_key_entry *pos, *new;
+
+ if (!(key->frame_types & (1 << IEEE802154_FC_TYPE_MAC_CMD)) &&
+ key->cmd_frame_ids)
+ return -EINVAL;
+
+ list_for_each_entry(pos, &sec->table.keys, list) {
+ if (llsec_key_id_equal(&pos->id, id))
+ return -EEXIST;
+
+ if (memcmp(pos->key->key, key->key,
+ IEEE802154_LLSEC_KEY_SIZE))
+ continue;
+
+ mkey = container_of(pos->key, struct mac802154_llsec_key, key);
+
+ /* Don't allow multiple instances of the same AES key to have
+ * different allowed frame types/command frame ids, as this is
+ * not possible in the 802.15.4 PIB.
+ */
+ if (pos->key->frame_types != key->frame_types ||
+ pos->key->cmd_frame_ids != key->cmd_frame_ids)
+ return -EEXIST;
+
+ break;
+ }
+
+ new = kzalloc(sizeof(*new), GFP_KERNEL);
+ if (!new)
+ return -ENOMEM;
+
+ if (!mkey)
+ mkey = llsec_key_alloc(key);
+ else
+ mkey = llsec_key_get(mkey);
+
+ if (!mkey)
+ goto fail;
+
+ new->id = *id;
+ new->key = &mkey->key;
+
+ list_add_rcu(&new->list, &sec->table.keys);
+
+ return 0;
+
+fail:
+ kfree(new);
+ return -ENOMEM;
+}
+
+int mac802154_llsec_key_del(struct mac802154_llsec *sec,
+ const struct ieee802154_llsec_key_id *key)
+{
+ struct ieee802154_llsec_key_entry *pos;
+
+ list_for_each_entry(pos, &sec->table.keys, list) {
+ struct mac802154_llsec_key *mkey;
+
+ mkey = container_of(pos->key, struct mac802154_llsec_key, key);
+
+ if (llsec_key_id_equal(&pos->id, key)) {
+ list_del_rcu(&pos->list);
+ llsec_key_put(mkey);
+ return 0;
+ }
+ }
+
+ return -ENOENT;
+}
+
+static bool llsec_dev_use_shortaddr(__le16 short_addr)
+{
+ return short_addr != cpu_to_le16(IEEE802154_ADDR_UNDEF) &&
+ short_addr != cpu_to_le16(0xffff);
+}
+
+static u32 llsec_dev_hash_short(__le16 short_addr, __le16 pan_id)
+{
+ return ((__force u16)short_addr) << 16 | (__force u16)pan_id;
+}
+
+static u64 llsec_dev_hash_long(__le64 hwaddr)
+{
+ return (__force u64)hwaddr;
+}
+
+static struct mac802154_llsec_device*
+llsec_dev_find_short(struct mac802154_llsec *sec, __le16 short_addr,
+ __le16 pan_id)
+{
+ struct mac802154_llsec_device *dev;
+ u32 key = llsec_dev_hash_short(short_addr, pan_id);
+
+ hash_for_each_possible_rcu(sec->devices_short, dev, bucket_s, key) {
+ if (dev->dev.short_addr == short_addr &&
+ dev->dev.pan_id == pan_id)
+ return dev;
+ }
+
+ return NULL;
+}
+
+static struct mac802154_llsec_device*
+llsec_dev_find_long(struct mac802154_llsec *sec, __le64 hwaddr)
+{
+ struct mac802154_llsec_device *dev;
+ u64 key = llsec_dev_hash_long(hwaddr);
+
+ hash_for_each_possible_rcu(sec->devices_hw, dev, bucket_hw, key) {
+ if (dev->dev.hwaddr == hwaddr)
+ return dev;
+ }
+
+ return NULL;
+}
+
+static void llsec_dev_free(struct mac802154_llsec_device *dev)
+{
+ struct ieee802154_llsec_device_key *pos, *pn;
+ struct mac802154_llsec_device_key *devkey;
+
+ list_for_each_entry_safe(pos, pn, &dev->dev.keys, list) {
+ devkey = container_of(pos, struct mac802154_llsec_device_key,
+ devkey);
+
+ list_del(&pos->list);
+ kfree(devkey);
+ }
+
+ kfree(dev);
+}
+
+int mac802154_llsec_dev_add(struct mac802154_llsec *sec,
+ const struct ieee802154_llsec_device *dev)
+{
+ struct mac802154_llsec_device *entry;
+ u32 skey = llsec_dev_hash_short(dev->short_addr, dev->pan_id);
+ u64 hwkey = llsec_dev_hash_long(dev->hwaddr);
+
+ BUILD_BUG_ON(sizeof(hwkey) != IEEE802154_ADDR_LEN);
+
+ if ((llsec_dev_use_shortaddr(dev->short_addr) &&
+ llsec_dev_find_short(sec, dev->short_addr, dev->pan_id)) ||
+ llsec_dev_find_long(sec, dev->hwaddr))
+ return -EEXIST;
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->dev = *dev;
+ spin_lock_init(&entry->lock);
+ INIT_LIST_HEAD(&entry->dev.keys);
+
+ if (llsec_dev_use_shortaddr(dev->short_addr))
+ hash_add_rcu(sec->devices_short, &entry->bucket_s, skey);
+ else
+ INIT_HLIST_NODE(&entry->bucket_s);
+
+ hash_add_rcu(sec->devices_hw, &entry->bucket_hw, hwkey);
+ list_add_tail_rcu(&entry->dev.list, &sec->table.devices);
+
+ return 0;
+}
+
+static void llsec_dev_free_rcu(struct rcu_head *rcu)
+{
+ llsec_dev_free(container_of(rcu, struct mac802154_llsec_device, rcu));
+}
+
+int mac802154_llsec_dev_del(struct mac802154_llsec *sec, __le64 device_addr)
+{
+ struct mac802154_llsec_device *pos;
+
+ pos = llsec_dev_find_long(sec, device_addr);
+ if (!pos)
+ return -ENOENT;
+
+ hash_del_rcu(&pos->bucket_s);
+ hash_del_rcu(&pos->bucket_hw);
+ call_rcu(&pos->rcu, llsec_dev_free_rcu);
+
+ return 0;
+}
+
+static struct mac802154_llsec_device_key*
+llsec_devkey_find(struct mac802154_llsec_device *dev,
+ const struct ieee802154_llsec_key_id *key)
+{
+ struct ieee802154_llsec_device_key *devkey;
+
+ list_for_each_entry_rcu(devkey, &dev->dev.keys, list) {
+ if (!llsec_key_id_equal(key, &devkey->key_id))
+ continue;
+
+ return container_of(devkey, struct mac802154_llsec_device_key,
+ devkey);
+ }
+
+ return NULL;
+}
+
+int mac802154_llsec_devkey_add(struct mac802154_llsec *sec,
+ __le64 dev_addr,
+ const struct ieee802154_llsec_device_key *key)
+{
+ struct mac802154_llsec_device *dev;
+ struct mac802154_llsec_device_key *devkey;
+
+ dev = llsec_dev_find_long(sec, dev_addr);
+
+ if (!dev)
+ return -ENOENT;
+
+ if (llsec_devkey_find(dev, &key->key_id))
+ return -EEXIST;
+
+ devkey = kmalloc(sizeof(*devkey), GFP_KERNEL);
+ if (!devkey)
+ return -ENOMEM;
+
+ devkey->devkey = *key;
+ list_add_tail_rcu(&devkey->devkey.list, &dev->dev.keys);
+ return 0;
+}
+
+int mac802154_llsec_devkey_del(struct mac802154_llsec *sec,
+ __le64 dev_addr,
+ const struct ieee802154_llsec_device_key *key)
+{
+ struct mac802154_llsec_device *dev;
+ struct mac802154_llsec_device_key *devkey;
+
+ dev = llsec_dev_find_long(sec, dev_addr);
+
+ if (!dev)
+ return -ENOENT;
+
+ devkey = llsec_devkey_find(dev, &key->key_id);
+ if (!devkey)
+ return -ENOENT;
+
+ list_del_rcu(&devkey->devkey.list);
+ kfree_rcu(devkey, rcu);
+ return 0;
+}
+
+static struct mac802154_llsec_seclevel*
+llsec_find_seclevel(const struct mac802154_llsec *sec,
+ const struct ieee802154_llsec_seclevel *sl)
+{
+ struct ieee802154_llsec_seclevel *pos;
+
+ list_for_each_entry(pos, &sec->table.security_levels, list) {
+ if (pos->frame_type != sl->frame_type ||
+ (pos->frame_type == IEEE802154_FC_TYPE_MAC_CMD &&
+ pos->cmd_frame_id != sl->cmd_frame_id) ||
+ pos->device_override != sl->device_override ||
+ pos->sec_levels != sl->sec_levels)
+ continue;
+
+ return container_of(pos, struct mac802154_llsec_seclevel,
+ level);
+ }
+
+ return NULL;
+}
+
+int mac802154_llsec_seclevel_add(struct mac802154_llsec *sec,
+ const struct ieee802154_llsec_seclevel *sl)
+{
+ struct mac802154_llsec_seclevel *entry;
+
+ if (llsec_find_seclevel(sec, sl))
+ return -EEXIST;
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->level = *sl;
+
+ list_add_tail_rcu(&entry->level.list, &sec->table.security_levels);
+
+ return 0;
+}
+
+int mac802154_llsec_seclevel_del(struct mac802154_llsec *sec,
+ const struct ieee802154_llsec_seclevel *sl)
+{
+ struct mac802154_llsec_seclevel *pos;
+
+ pos = llsec_find_seclevel(sec, sl);
+ if (!pos)
+ return -ENOENT;
+
+ list_del_rcu(&pos->level.list);
+ kfree_rcu(pos, rcu);
+
+ return 0;
+}
+
+static int llsec_recover_addr(struct mac802154_llsec *sec,
+ struct ieee802154_addr *addr)
+{
+ __le16 caddr = sec->params.coord_shortaddr;
+
+ addr->pan_id = sec->params.pan_id;
+
+ if (caddr == cpu_to_le16(IEEE802154_ADDR_BROADCAST)) {
+ return -EINVAL;
+ } else if (caddr == cpu_to_le16(IEEE802154_ADDR_UNDEF)) {
+ addr->extended_addr = sec->params.coord_hwaddr;
+ addr->mode = IEEE802154_ADDR_LONG;
+ } else {
+ addr->short_addr = sec->params.coord_shortaddr;
+ addr->mode = IEEE802154_ADDR_SHORT;
+ }
+
+ return 0;
+}
+
+static struct mac802154_llsec_key*
+llsec_lookup_key(struct mac802154_llsec *sec,
+ const struct ieee802154_hdr *hdr,
+ const struct ieee802154_addr *addr,
+ struct ieee802154_llsec_key_id *key_id)
+{
+ struct ieee802154_addr devaddr = *addr;
+ u8 key_id_mode = hdr->sec.key_id_mode;
+ struct ieee802154_llsec_key_entry *key_entry;
+ struct mac802154_llsec_key *key;
+
+ if (key_id_mode == IEEE802154_SCF_KEY_IMPLICIT &&
+ devaddr.mode == IEEE802154_ADDR_NONE) {
+ if (hdr->fc.type == IEEE802154_FC_TYPE_BEACON) {
+ devaddr.extended_addr = sec->params.coord_hwaddr;
+ devaddr.mode = IEEE802154_ADDR_LONG;
+ } else if (llsec_recover_addr(sec, &devaddr) < 0) {
+ return NULL;
+ }
+ }
+
+ list_for_each_entry_rcu(key_entry, &sec->table.keys, list) {
+ const struct ieee802154_llsec_key_id *id = &key_entry->id;
+
+ if (!(key_entry->key->frame_types & BIT(hdr->fc.type)))
+ continue;
+
+ if (id->mode != key_id_mode)
+ continue;
+
+ if (key_id_mode == IEEE802154_SCF_KEY_IMPLICIT) {
+ if (ieee802154_addr_equal(&devaddr, &id->device_addr))
+ goto found;
+ } else {
+ if (id->id != hdr->sec.key_id)
+ continue;
+
+ if ((key_id_mode == IEEE802154_SCF_KEY_INDEX) ||
+ (key_id_mode == IEEE802154_SCF_KEY_SHORT_INDEX &&
+ id->short_source == hdr->sec.short_src) ||
+ (key_id_mode == IEEE802154_SCF_KEY_HW_INDEX &&
+ id->extended_source == hdr->sec.extended_src))
+ goto found;
+ }
+ }
+
+ return NULL;
+
+found:
+ key = container_of(key_entry->key, struct mac802154_llsec_key, key);
+ if (key_id)
+ *key_id = key_entry->id;
+ return llsec_key_get(key);
+}
+
+static void llsec_geniv(u8 iv[16], __le64 addr,
+ const struct ieee802154_sechdr *sec)
+{
+ __be64 addr_bytes = (__force __be64) swab64((__force u64) addr);
+ __be32 frame_counter = (__force __be32) swab32((__force u32) sec->frame_counter);
+
+ iv[0] = 1; /* L' = L - 1 = 1 */
+ memcpy(iv + 1, &addr_bytes, sizeof(addr_bytes));
+ memcpy(iv + 9, &frame_counter, sizeof(frame_counter));
+ iv[13] = sec->level;
+ iv[14] = 0;
+ iv[15] = 1;
+}
+
+static int
+llsec_do_encrypt_unauth(struct sk_buff *skb, const struct mac802154_llsec *sec,
+ const struct ieee802154_hdr *hdr,
+ struct mac802154_llsec_key *key)
+{
+ u8 iv[16];
+ struct scatterlist src;
+ struct blkcipher_desc req = {
+ .tfm = key->tfm0,
+ .info = iv,
+ .flags = 0,
+ };
+
+ llsec_geniv(iv, sec->params.hwaddr, &hdr->sec);
+ sg_init_one(&src, skb->data, skb->len);
+ return crypto_blkcipher_encrypt_iv(&req, &src, &src, skb->len);
+}
+
+static struct crypto_aead*
+llsec_tfm_by_len(struct mac802154_llsec_key *key, int authlen)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(key->tfm); i++)
+ if (crypto_aead_authsize(key->tfm[i]) == authlen)
+ return key->tfm[i];
+
+ BUG();
+}
+
+static int
+llsec_do_encrypt_auth(struct sk_buff *skb, const struct mac802154_llsec *sec,
+ const struct ieee802154_hdr *hdr,
+ struct mac802154_llsec_key *key)
+{
+ u8 iv[16];
+ unsigned char *data;
+ int authlen, assoclen, datalen, rc;
+ struct scatterlist src, assoc[2], dst[2];
+ struct aead_request *req;
+
+ authlen = ieee802154_sechdr_authtag_len(&hdr->sec);
+ llsec_geniv(iv, sec->params.hwaddr, &hdr->sec);
+
+ req = aead_request_alloc(llsec_tfm_by_len(key, authlen), GFP_ATOMIC);
+ if (!req)
+ return -ENOMEM;
+
+ sg_init_table(assoc, 2);
+ sg_set_buf(&assoc[0], skb_mac_header(skb), skb->mac_len);
+ assoclen = skb->mac_len;
+
+ data = skb_mac_header(skb) + skb->mac_len;
+ datalen = skb_tail_pointer(skb) - data;
+
+ if (hdr->sec.level & IEEE802154_SCF_SECLEVEL_ENC) {
+ sg_set_buf(&assoc[1], data, 0);
+ } else {
+ sg_set_buf(&assoc[1], data, datalen);
+ assoclen += datalen;
+ datalen = 0;
+ }
+
+ sg_init_one(&src, data, datalen);
+
+ sg_init_table(dst, 2);
+ sg_set_buf(&dst[0], data, datalen);
+ sg_set_buf(&dst[1], skb_put(skb, authlen), authlen);
+
+ aead_request_set_callback(req, 0, NULL, NULL);
+ aead_request_set_assoc(req, assoc, assoclen);
+ aead_request_set_crypt(req, &src, dst, datalen, iv);
+
+ rc = crypto_aead_encrypt(req);
+
+ kfree(req);
+
+ return rc;
+}
+
+static int llsec_do_encrypt(struct sk_buff *skb,
+ const struct mac802154_llsec *sec,
+ const struct ieee802154_hdr *hdr,
+ struct mac802154_llsec_key *key)
+{
+ if (hdr->sec.level == IEEE802154_SCF_SECLEVEL_ENC)
+ return llsec_do_encrypt_unauth(skb, sec, hdr, key);
+ else
+ return llsec_do_encrypt_auth(skb, sec, hdr, key);
+}
+
+int mac802154_llsec_encrypt(struct mac802154_llsec *sec, struct sk_buff *skb)
+{
+ struct ieee802154_hdr hdr;
+ int rc, authlen, hlen;
+ struct mac802154_llsec_key *key;
+ u32 frame_ctr;
+
+ hlen = ieee802154_hdr_pull(skb, &hdr);
+
+ if (hlen < 0 || hdr.fc.type != IEEE802154_FC_TYPE_DATA)
+ return -EINVAL;
+
+ if (!hdr.fc.security_enabled || hdr.sec.level == 0) {
+ skb_push(skb, hlen);
+ return 0;
+ }
+
+ authlen = ieee802154_sechdr_authtag_len(&hdr.sec);
+
+ if (skb->len + hlen + authlen + IEEE802154_MFR_SIZE > IEEE802154_MTU)
+ return -EMSGSIZE;
+
+ rcu_read_lock();
+
+ read_lock_bh(&sec->lock);
+
+ if (!sec->params.enabled) {
+ rc = -EINVAL;
+ goto fail_read;
+ }
+
+ key = llsec_lookup_key(sec, &hdr, &hdr.dest, NULL);
+ if (!key) {
+ rc = -ENOKEY;
+ goto fail_read;
+ }
+
+ read_unlock_bh(&sec->lock);
+
+ write_lock_bh(&sec->lock);
+
+ frame_ctr = be32_to_cpu(sec->params.frame_counter);
+ hdr.sec.frame_counter = cpu_to_le32(frame_ctr);
+ if (frame_ctr == 0xFFFFFFFF) {
+ write_unlock_bh(&sec->lock);
+ llsec_key_put(key);
+ rc = -EOVERFLOW;
+ goto fail;
+ }
+
+ sec->params.frame_counter = cpu_to_be32(frame_ctr + 1);
+
+ write_unlock_bh(&sec->lock);
+
+ rcu_read_unlock();
+
+ skb->mac_len = ieee802154_hdr_push(skb, &hdr);
+ skb_reset_mac_header(skb);
+
+ rc = llsec_do_encrypt(skb, sec, &hdr, key);
+ llsec_key_put(key);
+
+ return rc;
+
+fail_read:
+ read_unlock_bh(&sec->lock);
+fail:
+ rcu_read_unlock();
+ return rc;
+}
+
+static struct mac802154_llsec_device*
+llsec_lookup_dev(struct mac802154_llsec *sec,
+ const struct ieee802154_addr *addr)
+{
+ struct ieee802154_addr devaddr = *addr;
+ struct mac802154_llsec_device *dev = NULL;
+
+ if (devaddr.mode == IEEE802154_ADDR_NONE &&
+ llsec_recover_addr(sec, &devaddr) < 0)
+ return NULL;
+
+ if (devaddr.mode == IEEE802154_ADDR_SHORT) {
+ u32 key = llsec_dev_hash_short(devaddr.short_addr,
+ devaddr.pan_id);
+
+ hash_for_each_possible_rcu(sec->devices_short, dev,
+ bucket_s, key) {
+ if (dev->dev.pan_id == devaddr.pan_id &&
+ dev->dev.short_addr == devaddr.short_addr)
+ return dev;
+ }
+ } else {
+ u64 key = llsec_dev_hash_long(devaddr.extended_addr);
+
+ hash_for_each_possible_rcu(sec->devices_hw, dev,
+ bucket_hw, key) {
+ if (dev->dev.hwaddr == devaddr.extended_addr)
+ return dev;
+ }
+ }
+
+ return NULL;
+}
+
+static int
+llsec_lookup_seclevel(const struct mac802154_llsec *sec,
+ u8 frame_type, u8 cmd_frame_id,
+ struct ieee802154_llsec_seclevel *rlevel)
+{
+ struct ieee802154_llsec_seclevel *level;
+
+ list_for_each_entry_rcu(level, &sec->table.security_levels, list) {
+ if (level->frame_type == frame_type &&
+ (frame_type != IEEE802154_FC_TYPE_MAC_CMD ||
+ level->cmd_frame_id == cmd_frame_id)) {
+ *rlevel = *level;
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static int
+llsec_do_decrypt_unauth(struct sk_buff *skb, const struct mac802154_llsec *sec,
+ const struct ieee802154_hdr *hdr,
+ struct mac802154_llsec_key *key, __le64 dev_addr)
+{
+ u8 iv[16];
+ unsigned char *data;
+ int datalen;
+ struct scatterlist src;
+ struct blkcipher_desc req = {
+ .tfm = key->tfm0,
+ .info = iv,
+ .flags = 0,
+ };
+
+ llsec_geniv(iv, dev_addr, &hdr->sec);
+ data = skb_mac_header(skb) + skb->mac_len;
+ datalen = skb_tail_pointer(skb) - data;
+
+ sg_init_one(&src, data, datalen);
+
+ return crypto_blkcipher_decrypt_iv(&req, &src, &src, datalen);
+}
+
+static int
+llsec_do_decrypt_auth(struct sk_buff *skb, const struct mac802154_llsec *sec,
+ const struct ieee802154_hdr *hdr,
+ struct mac802154_llsec_key *key, __le64 dev_addr)
+{
+ u8 iv[16];
+ unsigned char *data;
+ int authlen, datalen, assoclen, rc;
+ struct scatterlist src, assoc[2];
+ struct aead_request *req;
+
+ authlen = ieee802154_sechdr_authtag_len(&hdr->sec);
+ llsec_geniv(iv, dev_addr, &hdr->sec);
+
+ req = aead_request_alloc(llsec_tfm_by_len(key, authlen), GFP_ATOMIC);
+ if (!req)
+ return -ENOMEM;
+
+ sg_init_table(assoc, 2);
+ sg_set_buf(&assoc[0], skb_mac_header(skb), skb->mac_len);
+ assoclen = skb->mac_len;
+
+ data = skb_mac_header(skb) + skb->mac_len;
+ datalen = skb_tail_pointer(skb) - data;
+
+ if (hdr->sec.level & IEEE802154_SCF_SECLEVEL_ENC) {
+ sg_set_buf(&assoc[1], data, 0);
+ } else {
+ sg_set_buf(&assoc[1], data, datalen - authlen);
+ assoclen += datalen - authlen;
+ data += datalen - authlen;
+ datalen = authlen;
+ }
+
+ sg_init_one(&src, data, datalen);
+
+ aead_request_set_callback(req, 0, NULL, NULL);
+ aead_request_set_assoc(req, assoc, assoclen);
+ aead_request_set_crypt(req, &src, &src, datalen, iv);
+
+ rc = crypto_aead_decrypt(req);
+
+ kfree(req);
+ skb_trim(skb, skb->len - authlen);
+
+ return rc;
+}
+
+static int
+llsec_do_decrypt(struct sk_buff *skb, const struct mac802154_llsec *sec,
+ const struct ieee802154_hdr *hdr,
+ struct mac802154_llsec_key *key, __le64 dev_addr)
+{
+ if (hdr->sec.level == IEEE802154_SCF_SECLEVEL_ENC)
+ return llsec_do_decrypt_unauth(skb, sec, hdr, key, dev_addr);
+ else
+ return llsec_do_decrypt_auth(skb, sec, hdr, key, dev_addr);
+}
+
+static int
+llsec_update_devkey_record(struct mac802154_llsec_device *dev,
+ const struct ieee802154_llsec_key_id *in_key)
+{
+ struct mac802154_llsec_device_key *devkey;
+
+ devkey = llsec_devkey_find(dev, in_key);
+
+ if (!devkey) {
+ struct mac802154_llsec_device_key *next;
+
+ next = kzalloc(sizeof(*devkey), GFP_ATOMIC);
+ if (!next)
+ return -ENOMEM;
+
+ next->devkey.key_id = *in_key;
+
+ spin_lock_bh(&dev->lock);
+
+ devkey = llsec_devkey_find(dev, in_key);
+ if (!devkey)
+ list_add_rcu(&next->devkey.list, &dev->dev.keys);
+ else
+ kfree(next);
+
+ spin_unlock_bh(&dev->lock);
+ }
+
+ return 0;
+}
+
+static int
+llsec_update_devkey_info(struct mac802154_llsec_device *dev,
+ const struct ieee802154_llsec_key_id *in_key,
+ u32 frame_counter)
+{
+ struct mac802154_llsec_device_key *devkey = NULL;
+
+ if (dev->dev.key_mode == IEEE802154_LLSEC_DEVKEY_RESTRICT) {
+ devkey = llsec_devkey_find(dev, in_key);
+ if (!devkey)
+ return -ENOENT;
+ }
+
+ if (dev->dev.key_mode == IEEE802154_LLSEC_DEVKEY_RECORD) {
+ int rc = llsec_update_devkey_record(dev, in_key);
+
+ if (rc < 0)
+ return rc;
+ }
+
+ spin_lock_bh(&dev->lock);
+
+ if ((!devkey && frame_counter < dev->dev.frame_counter) ||
+ (devkey && frame_counter < devkey->devkey.frame_counter)) {
+ spin_unlock_bh(&dev->lock);
+ return -EINVAL;
+ }
+
+ if (devkey)
+ devkey->devkey.frame_counter = frame_counter + 1;
+ else
+ dev->dev.frame_counter = frame_counter + 1;
+
+ spin_unlock_bh(&dev->lock);
+
+ return 0;
+}
+
+int mac802154_llsec_decrypt(struct mac802154_llsec *sec, struct sk_buff *skb)
+{
+ struct ieee802154_hdr hdr;
+ struct mac802154_llsec_key *key;
+ struct ieee802154_llsec_key_id key_id;
+ struct mac802154_llsec_device *dev;
+ struct ieee802154_llsec_seclevel seclevel;
+ int err;
+ __le64 dev_addr;
+ u32 frame_ctr;
+
+ if (ieee802154_hdr_peek(skb, &hdr) < 0)
+ return -EINVAL;
+ if (!hdr.fc.security_enabled)
+ return 0;
+ if (hdr.fc.version == 0)
+ return -EINVAL;
+
+ read_lock_bh(&sec->lock);
+ if (!sec->params.enabled) {
+ read_unlock_bh(&sec->lock);
+ return -EINVAL;
+ }
+ read_unlock_bh(&sec->lock);
+
+ rcu_read_lock();
+
+ key = llsec_lookup_key(sec, &hdr, &hdr.source, &key_id);
+ if (!key) {
+ err = -ENOKEY;
+ goto fail;
+ }
+
+ dev = llsec_lookup_dev(sec, &hdr.source);
+ if (!dev) {
+ err = -EINVAL;
+ goto fail_dev;
+ }
+
+ if (llsec_lookup_seclevel(sec, hdr.fc.type, 0, &seclevel) < 0) {
+ err = -EINVAL;
+ goto fail_dev;
+ }
+
+ if (!(seclevel.sec_levels & BIT(hdr.sec.level)) &&
+ (hdr.sec.level == 0 && seclevel.device_override &&
+ !dev->dev.seclevel_exempt)) {
+ err = -EINVAL;
+ goto fail_dev;
+ }
+
+ frame_ctr = le32_to_cpu(hdr.sec.frame_counter);
+
+ if (frame_ctr == 0xffffffff) {
+ err = -EOVERFLOW;
+ goto fail_dev;
+ }
+
+ err = llsec_update_devkey_info(dev, &key_id, frame_ctr);
+ if (err)
+ goto fail_dev;
+
+ dev_addr = dev->dev.hwaddr;
+
+ rcu_read_unlock();
+
+ err = llsec_do_decrypt(skb, sec, &hdr, key, dev_addr);
+ llsec_key_put(key);
+ return err;
+
+fail_dev:
+ llsec_key_put(key);
+fail:
+ rcu_read_unlock();
+ return err;
+}