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firmware/br-ext-chip-allwinner/board/v83x/kernel/patches/00000-fs_crypto_keyinfo.c.p...

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diff -drupN a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
--- a/fs/crypto/keyinfo.c 2018-08-06 17:23:04.000000000 +0300
+++ b/fs/crypto/keyinfo.c 2022-06-12 05:28:14.000000000 +0300
@@ -10,36 +10,32 @@
#include <keys/user-type.h>
#include <linux/scatterlist.h>
-#include <linux/fscrypto.h>
-
-static void derive_crypt_complete(struct crypto_async_request *req, int rc)
-{
- struct fscrypt_completion_result *ecr = req->data;
-
- if (rc == -EINPROGRESS)
- return;
+#include <linux/ratelimit.h>
+#include <crypto/aes.h>
+#include <crypto/sha.h>
+#include <crypto/skcipher.h>
+#include "fscrypt_private.h"
- ecr->res = rc;
- complete(&ecr->completion);
-}
+static struct crypto_shash *essiv_hash_tfm;
/**
* derive_key_aes() - Derive a key using AES-128-ECB
* @deriving_key: Encryption key used for derivation.
* @source_key: Source key to which to apply derivation.
- * @derived_key: Derived key.
+ * @derived_raw_key: Derived raw key.
*
* Return: Zero on success; non-zero otherwise.
*/
static int derive_key_aes(u8 deriving_key[FS_AES_128_ECB_KEY_SIZE],
- u8 source_key[FS_AES_256_XTS_KEY_SIZE],
- u8 derived_key[FS_AES_256_XTS_KEY_SIZE])
+ const struct fscrypt_key *source_key,
+ u8 derived_raw_key[FS_MAX_KEY_SIZE])
{
int res = 0;
struct skcipher_request *req = NULL;
- DECLARE_FS_COMPLETION_RESULT(ecr);
+ DECLARE_CRYPTO_WAIT(wait);
struct scatterlist src_sg, dst_sg;
struct crypto_skcipher *tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
+ char *buf;
if (IS_ERR(tfm)) {
res = PTR_ERR(tfm);
@@ -54,49 +50,52 @@ static int derive_key_aes(u8 deriving_ke
}
skcipher_request_set_callback(req,
CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
- derive_crypt_complete, &ecr);
+ crypto_req_done, &wait);
res = crypto_skcipher_setkey(tfm, deriving_key,
FS_AES_128_ECB_KEY_SIZE);
if (res < 0)
goto out;
-
- sg_init_one(&src_sg, source_key, FS_AES_256_XTS_KEY_SIZE);
- sg_init_one(&dst_sg, derived_key, FS_AES_256_XTS_KEY_SIZE);
- skcipher_request_set_crypt(req, &src_sg, &dst_sg,
- FS_AES_256_XTS_KEY_SIZE, NULL);
- res = crypto_skcipher_encrypt(req);
- if (res == -EINPROGRESS || res == -EBUSY) {
- wait_for_completion(&ecr.completion);
- res = ecr.res;
+ /*the source buf address is not word align,so malloc to ss*/
+ buf = kmalloc(FS_MAX_KEY_SIZE, GFP_NOFS);
+ if (buf == NULL) {
+ pr_err("kmalloc fail\n");
+ res = -EINVAL;
+ goto out;
}
+ memcpy(buf, (void *)source_key->raw, source_key->size);
+
+ sg_init_one(&src_sg, buf, source_key->size);
+ /*sg_init_one(&src_sg, source_key->raw, source_key->size);*/
+ sg_init_one(&dst_sg, derived_raw_key, source_key->size);
+ skcipher_request_set_crypt(req, &src_sg, &dst_sg, source_key->size,
+ NULL);
+ res = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
out:
skcipher_request_free(req);
crypto_free_skcipher(tfm);
+ if (buf != NULL)
+ kzfree(buf);
return res;
}
static int validate_user_key(struct fscrypt_info *crypt_info,
struct fscrypt_context *ctx, u8 *raw_key,
- u8 *prefix, int prefix_size)
+ const char *prefix, int min_keysize)
{
- u8 *full_key_descriptor;
+ char *description;
struct key *keyring_key;
struct fscrypt_key *master_key;
const struct user_key_payload *ukp;
- int full_key_len = prefix_size + (FS_KEY_DESCRIPTOR_SIZE * 2) + 1;
int res;
- full_key_descriptor = kmalloc(full_key_len, GFP_NOFS);
- if (!full_key_descriptor)
+ description = kasprintf(GFP_NOFS, "%s%*phN", prefix,
+ FS_KEY_DESCRIPTOR_SIZE,
+ ctx->master_key_descriptor);
+ if (!description)
return -ENOMEM;
- memcpy(full_key_descriptor, prefix, prefix_size);
- sprintf(full_key_descriptor + prefix_size,
- "%*phN", FS_KEY_DESCRIPTOR_SIZE,
- ctx->master_key_descriptor);
- full_key_descriptor[full_key_len - 1] = '\0';
- keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL);
- kfree(full_key_descriptor);
+ keyring_key = request_key(&key_type_logon, description, NULL);
+ kfree(description);
if (IS_ERR(keyring_key))
return PTR_ERR(keyring_key);
down_read(&keyring_key->sem);
@@ -107,7 +106,7 @@ static int validate_user_key(struct fscr
res = -ENOKEY;
goto out;
}
- ukp = user_key_payload(keyring_key);
+ ukp = user_key_payload_locked(keyring_key);
if (!ukp) {
/* key was revoked before we acquired its semaphore */
res = -EKEYREVOKED;
@@ -120,50 +119,63 @@ static int validate_user_key(struct fscr
master_key = (struct fscrypt_key *)ukp->data;
BUILD_BUG_ON(FS_AES_128_ECB_KEY_SIZE != FS_KEY_DERIVATION_NONCE_SIZE);
- if (master_key->size != FS_AES_256_XTS_KEY_SIZE) {
+ if (master_key->size < min_keysize || master_key->size > FS_MAX_KEY_SIZE
+ || master_key->size % AES_BLOCK_SIZE != 0) {
printk_once(KERN_WARNING
"%s: key size incorrect: %d\n",
__func__, master_key->size);
res = -ENOKEY;
goto out;
}
- res = derive_key_aes(ctx->nonce, master_key->raw, raw_key);
+
+ res = derive_key_aes(ctx->nonce, master_key, raw_key);
out:
up_read(&keyring_key->sem);
key_put(keyring_key);
return res;
}
+static const struct {
+ const char *cipher_str;
+ int keysize;
+} available_modes[] = {
+ [FS_ENCRYPTION_MODE_AES_256_XTS] = { "xts(aes)",
+ FS_AES_256_XTS_KEY_SIZE },
+ [FS_ENCRYPTION_MODE_AES_256_CTS] = { "cts(cbc(aes))",
+ FS_AES_256_CTS_KEY_SIZE },
+ [FS_ENCRYPTION_MODE_AES_128_CBC] = { "cbc(aes)",
+ FS_AES_128_CBC_KEY_SIZE },
+ [FS_ENCRYPTION_MODE_AES_128_CTS] = { "cts(cbc(aes))",
+ FS_AES_128_CTS_KEY_SIZE },
+ [FS_ENCRYPTION_MODE_SPECK128_256_XTS] = { "xts(speck128)", 64 },
+ [FS_ENCRYPTION_MODE_SPECK128_256_CTS] = { "cts(cbc(speck128))", 32 },
+};
+
static int determine_cipher_type(struct fscrypt_info *ci, struct inode *inode,
const char **cipher_str_ret, int *keysize_ret)
{
- if (S_ISREG(inode->i_mode)) {
- if (ci->ci_data_mode == FS_ENCRYPTION_MODE_AES_256_XTS) {
- *cipher_str_ret = "xts(aes)";
- *keysize_ret = FS_AES_256_XTS_KEY_SIZE;
- return 0;
- }
- pr_warn_once("fscrypto: unsupported contents encryption mode "
- "%d for inode %lu\n",
- ci->ci_data_mode, inode->i_ino);
- return -ENOKEY;
+ u32 mode;
+
+ if (!fscrypt_valid_enc_modes(ci->ci_data_mode, ci->ci_filename_mode)) {
+ pr_warn_ratelimited("fscrypt: inode %lu uses unsupported encryption modes (contents mode %d, filenames mode %d)\n",
+ inode->i_ino,
+ ci->ci_data_mode, ci->ci_filename_mode);
+ return -EINVAL;
}
- if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) {
- if (ci->ci_filename_mode == FS_ENCRYPTION_MODE_AES_256_CTS) {
- *cipher_str_ret = "cts(cbc(aes))";
- *keysize_ret = FS_AES_256_CTS_KEY_SIZE;
- return 0;
- }
- pr_warn_once("fscrypto: unsupported filenames encryption mode "
- "%d for inode %lu\n",
- ci->ci_filename_mode, inode->i_ino);
- return -ENOKEY;
+ if (S_ISREG(inode->i_mode)) {
+ mode = ci->ci_data_mode;
+ } else if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) {
+ mode = ci->ci_filename_mode;
+ } else {
+ WARN_ONCE(1, "fscrypt: filesystem tried to load encryption info for inode %lu, which is not encryptable (file type %d)\n",
+ inode->i_ino, (inode->i_mode & S_IFMT));
+ return -EINVAL;
}
- pr_warn_once("fscrypto: unsupported file type %d for inode %lu\n",
- (inode->i_mode & S_IFMT), inode->i_ino);
- return -ENOKEY;
+ *cipher_str_ret = available_modes[mode].cipher_str;
+ *keysize_ret = available_modes[mode].keysize;
+ return 0;
}
static void put_crypt_info(struct fscrypt_info *ci)
@@ -172,9 +184,76 @@ static void put_crypt_info(struct fscryp
return;
crypto_free_skcipher(ci->ci_ctfm);
+ crypto_free_cipher(ci->ci_essiv_tfm);
kmem_cache_free(fscrypt_info_cachep, ci);
}
+static int derive_essiv_salt(const u8 *key, int keysize, u8 *salt)
+{
+ struct crypto_shash *tfm = READ_ONCE(essiv_hash_tfm);
+
+ /* init hash transform on demand */
+ if (unlikely(!tfm)) {
+ struct crypto_shash *prev_tfm;
+
+ tfm = crypto_alloc_shash("sha256", 0, 0);
+ if (IS_ERR(tfm)) {
+ pr_warn_ratelimited("fscrypt: error allocating SHA-256 transform: %ld\n",
+ PTR_ERR(tfm));
+ return PTR_ERR(tfm);
+ }
+ prev_tfm = cmpxchg(&essiv_hash_tfm, NULL, tfm);
+ if (prev_tfm) {
+ crypto_free_shash(tfm);
+ tfm = prev_tfm;
+ }
+ }
+
+ {
+ SHASH_DESC_ON_STACK(desc, tfm);
+ desc->tfm = tfm;
+ desc->flags = 0;
+
+ return crypto_shash_digest(desc, key, keysize, salt);
+ }
+}
+
+static int init_essiv_generator(struct fscrypt_info *ci, const u8 *raw_key,
+ int keysize)
+{
+ int err;
+ struct crypto_cipher *essiv_tfm;
+ u8 salt[SHA256_DIGEST_SIZE];
+
+ essiv_tfm = crypto_alloc_cipher("aes", 0, 0);
+ if (IS_ERR(essiv_tfm))
+ return PTR_ERR(essiv_tfm);
+
+ ci->ci_essiv_tfm = essiv_tfm;
+
+ err = derive_essiv_salt(raw_key, keysize, salt);
+ if (err)
+ goto out;
+
+ /*
+ * Using SHA256 to derive the salt/key will result in AES-256 being
+ * used for IV generation. File contents encryption will still use the
+ * configured keysize (AES-128) nevertheless.
+ */
+ err = crypto_cipher_setkey(essiv_tfm, salt, sizeof(salt));
+ if (err)
+ goto out;
+
+out:
+ memzero_explicit(salt, sizeof(salt));
+ return err;
+}
+
+void __exit fscrypt_essiv_cleanup(void)
+{
+ crypto_free_shash(essiv_hash_tfm);
+}
+
int fscrypt_get_encryption_info(struct inode *inode)
{
struct fscrypt_info *crypt_info;
@@ -188,21 +267,21 @@ int fscrypt_get_encryption_info(struct i
if (inode->i_crypt_info)
return 0;
- res = fscrypt_initialize();
+ res = fscrypt_initialize(inode->i_sb->s_cop->flags);
if (res)
return res;
- if (!inode->i_sb->s_cop->get_context)
- return -EOPNOTSUPP;
-
res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
if (res < 0) {
- if (!fscrypt_dummy_context_enabled(inode))
+ if (!fscrypt_dummy_context_enabled(inode) ||
+ IS_ENCRYPTED(inode))
return res;
+ /* Fake up a context for an unencrypted directory */
+ memset(&ctx, 0, sizeof(ctx));
ctx.format = FS_ENCRYPTION_CONTEXT_FORMAT_V1;
ctx.contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS;
ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS;
- ctx.flags = 0;
+ memset(ctx.master_key_descriptor, 0x42, FS_KEY_DESCRIPTOR_SIZE);
} else if (res != sizeof(ctx)) {
return -EINVAL;
}
@@ -221,6 +300,7 @@ int fscrypt_get_encryption_info(struct i
crypt_info->ci_data_mode = ctx.contents_encryption_mode;
crypt_info->ci_filename_mode = ctx.filenames_encryption_mode;
crypt_info->ci_ctfm = NULL;
+ crypt_info->ci_essiv_tfm = NULL;
memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor,
sizeof(crypt_info->ci_master_key));
@@ -237,20 +317,12 @@ int fscrypt_get_encryption_info(struct i
if (!raw_key)
goto out;
- if (fscrypt_dummy_context_enabled(inode)) {
- memset(raw_key, 0x42, FS_AES_256_XTS_KEY_SIZE);
- goto got_key;
- }
-
- res = validate_user_key(crypt_info, &ctx, raw_key,
- FS_KEY_DESC_PREFIX, FS_KEY_DESC_PREFIX_SIZE);
+ res = validate_user_key(crypt_info, &ctx, raw_key, FS_KEY_DESC_PREFIX,
+ keysize);
if (res && inode->i_sb->s_cop->key_prefix) {
- u8 *prefix = NULL;
- int prefix_size, res2;
-
- prefix_size = inode->i_sb->s_cop->key_prefix(inode, &prefix);
- res2 = validate_user_key(crypt_info, &ctx, raw_key,
- prefix, prefix_size);
+ int res2 = validate_user_key(crypt_info, &ctx, raw_key,
+ inode->i_sb->s_cop->key_prefix,
+ keysize);
if (res2) {
if (res2 == -ENOKEY)
res = -ENOKEY;
@@ -259,22 +331,33 @@ int fscrypt_get_encryption_info(struct i
} else if (res) {
goto out;
}
-got_key:
ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
if (!ctfm || IS_ERR(ctfm)) {
res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
- printk(KERN_DEBUG
- "%s: error %d (inode %u) allocating crypto tfm\n",
- __func__, res, (unsigned) inode->i_ino);
+ pr_debug("%s: error %d (inode %lu) allocating crypto tfm\n",
+ __func__, res, inode->i_ino);
goto out;
}
crypt_info->ci_ctfm = ctfm;
crypto_skcipher_clear_flags(ctfm, ~0);
crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_REQ_WEAK_KEY);
+ /*
+ * if the provided key is longer than keysize, we use the first
+ * keysize bytes of the derived key only
+ */
res = crypto_skcipher_setkey(ctfm, raw_key, keysize);
if (res)
goto out;
+ if (S_ISREG(inode->i_mode) &&
+ crypt_info->ci_data_mode == FS_ENCRYPTION_MODE_AES_128_CBC) {
+ res = init_essiv_generator(crypt_info, raw_key, keysize);
+ if (res) {
+ pr_debug("%s: error %d (inode %lu) allocating essiv tfm\n",
+ __func__, res, inode->i_ino);
+ goto out;
+ }
+ }
if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) == NULL)
crypt_info = NULL;
out:
@@ -286,19 +369,9 @@ out:
}
EXPORT_SYMBOL(fscrypt_get_encryption_info);
-void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci)
+void fscrypt_put_encryption_info(struct inode *inode)
{
- struct fscrypt_info *prev;
-
- if (ci == NULL)
- ci = ACCESS_ONCE(inode->i_crypt_info);
- if (ci == NULL)
- return;
-
- prev = cmpxchg(&inode->i_crypt_info, ci, NULL);
- if (prev != ci)
- return;
-
- put_crypt_info(ci);
+ put_crypt_info(inode->i_crypt_info);
+ inode->i_crypt_info = NULL;
}
EXPORT_SYMBOL(fscrypt_put_encryption_info);
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