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-rw-r--r--fs/ext4/Kconfig1
-rw-r--r--fs/ext4/crypto_fname.c3
-rw-r--r--fs/ext4/crypto_key.c101
-rw-r--r--fs/ext4/ext4.h1
-rw-r--r--fs/ext4/ext4_crypto.h4
-rw-r--r--fs/ext4/inline.c12
-rw-r--r--fs/ext4/inode.c50
-rw-r--r--fs/ext4/readpage.c6
8 files changed, 159 insertions, 19 deletions
diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig
index b46e9fc64196..3c8293215603 100644
--- a/fs/ext4/Kconfig
+++ b/fs/ext4/Kconfig
@@ -106,6 +106,7 @@ config EXT4_ENCRYPTION
select CRYPTO_ECB
select CRYPTO_XTS
select CRYPTO_CTS
+ select CRYPTO_HEH
select CRYPTO_CTR
select CRYPTO_SHA256
select KEYS
diff --git a/fs/ext4/crypto_fname.c b/fs/ext4/crypto_fname.c
index 2fbef8a14760..e2645ca9b95e 100644
--- a/fs/ext4/crypto_fname.c
+++ b/fs/ext4/crypto_fname.c
@@ -44,7 +44,8 @@ static void ext4_dir_crypt_complete(struct crypto_async_request *req, int res)
bool ext4_valid_filenames_enc_mode(uint32_t mode)
{
- return (mode == EXT4_ENCRYPTION_MODE_AES_256_CTS);
+ return (mode == EXT4_ENCRYPTION_MODE_AES_256_CTS ||
+ mode == EXT4_ENCRYPTION_MODE_AES_256_HEH);
}
static unsigned max_name_len(struct inode *inode)
diff --git a/fs/ext4/crypto_key.c b/fs/ext4/crypto_key.c
index 9a16d1e75a49..98d58c8ee804 100644
--- a/fs/ext4/crypto_key.c
+++ b/fs/ext4/crypto_key.c
@@ -29,16 +29,16 @@ static void derive_crypt_complete(struct crypto_async_request *req, int rc)
}
/**
- * ext4_derive_key_aes() - Derive a key using AES-128-ECB
+ * ext4_derive_key_v1() - 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.
*
- * Return: Zero on success; non-zero otherwise.
+ * Return: 0 on success, -errno on failure
*/
-static int ext4_derive_key_aes(char deriving_key[EXT4_AES_128_ECB_KEY_SIZE],
- char source_key[EXT4_AES_256_XTS_KEY_SIZE],
- char derived_key[EXT4_AES_256_XTS_KEY_SIZE])
+static int ext4_derive_key_v1(const char deriving_key[EXT4_AES_128_ECB_KEY_SIZE],
+ const char source_key[EXT4_AES_256_XTS_KEY_SIZE],
+ char derived_key[EXT4_AES_256_XTS_KEY_SIZE])
{
int res = 0;
struct ablkcipher_request *req = NULL;
@@ -83,6 +83,91 @@ out:
return res;
}
+/**
+ * ext4_derive_key_v2() - Derive a key non-reversibly
+ * @nonce: the nonce associated with the file
+ * @master_key: the master key referenced by the file
+ * @derived_key: (output) the resulting derived key
+ *
+ * This function computes the following:
+ * derived_key[0:127] = AES-256-ENCRYPT(master_key[0:255], nonce)
+ * derived_key[128:255] = AES-256-ENCRYPT(master_key[0:255], nonce ^ 0x01)
+ * derived_key[256:383] = AES-256-ENCRYPT(master_key[256:511], nonce)
+ * derived_key[384:511] = AES-256-ENCRYPT(master_key[256:511], nonce ^ 0x01)
+ *
+ * 'nonce ^ 0x01' denotes flipping the low order bit of the last byte.
+ *
+ * Unlike the v1 algorithm, the v2 algorithm is "non-reversible", meaning that
+ * compromising a derived key does not also compromise the master key.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ext4_derive_key_v2(const char nonce[EXT4_KEY_DERIVATION_NONCE_SIZE],
+ const char master_key[EXT4_MAX_KEY_SIZE],
+ char derived_key[EXT4_MAX_KEY_SIZE])
+{
+ const int noncelen = EXT4_KEY_DERIVATION_NONCE_SIZE;
+ struct crypto_cipher *tfm;
+ int err;
+ int i;
+
+ /*
+ * Since we only use each transform for a small number of encryptions,
+ * requesting just "aes" turns out to be significantly faster than
+ * "ecb(aes)", by about a factor of two.
+ */
+ tfm = crypto_alloc_cipher("aes", 0, 0);
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ BUILD_BUG_ON(4 * EXT4_KEY_DERIVATION_NONCE_SIZE != EXT4_MAX_KEY_SIZE);
+ BUILD_BUG_ON(2 * EXT4_AES_256_ECB_KEY_SIZE != EXT4_MAX_KEY_SIZE);
+ for (i = 0; i < 2; i++) {
+ memcpy(derived_key, nonce, noncelen);
+ memcpy(derived_key + noncelen, nonce, noncelen);
+ derived_key[2 * noncelen - 1] ^= 0x01;
+ err = crypto_cipher_setkey(tfm, master_key,
+ EXT4_AES_256_ECB_KEY_SIZE);
+ if (err)
+ break;
+ crypto_cipher_encrypt_one(tfm, derived_key, derived_key);
+ crypto_cipher_encrypt_one(tfm, derived_key + noncelen,
+ derived_key + noncelen);
+ master_key += EXT4_AES_256_ECB_KEY_SIZE;
+ derived_key += 2 * noncelen;
+ }
+ crypto_free_cipher(tfm);
+ return err;
+}
+
+/**
+ * ext4_derive_key() - Derive a per-file key from a nonce and master key
+ * @ctx: the encryption context associated with the file
+ * @master_key: the master key referenced by the file
+ * @derived_key: (output) the resulting derived key
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ext4_derive_key(const struct ext4_encryption_context *ctx,
+ const char master_key[EXT4_MAX_KEY_SIZE],
+ char derived_key[EXT4_MAX_KEY_SIZE])
+{
+ BUILD_BUG_ON(EXT4_AES_128_ECB_KEY_SIZE != EXT4_KEY_DERIVATION_NONCE_SIZE);
+ BUILD_BUG_ON(EXT4_AES_256_XTS_KEY_SIZE != EXT4_MAX_KEY_SIZE);
+
+ /*
+ * Although the key derivation algorithm is logically independent of the
+ * choice of encryption modes, in this kernel it is bundled with HEH
+ * encryption of filenames, which is another crypto improvement that
+ * requires an on-disk format change and requires userspace to specify
+ * different encryption policies.
+ */
+ if (ctx->filenames_encryption_mode == EXT4_ENCRYPTION_MODE_AES_256_HEH)
+ return ext4_derive_key_v2(ctx->nonce, master_key, derived_key);
+ else
+ return ext4_derive_key_v1(ctx->nonce, master_key, derived_key);
+}
+
void ext4_free_crypt_info(struct ext4_crypt_info *ci)
{
if (!ci)
@@ -182,6 +267,9 @@ retry:
case EXT4_ENCRYPTION_MODE_AES_256_CTS:
cipher_str = "cts(cbc(aes))";
break;
+ case EXT4_ENCRYPTION_MODE_AES_256_HEH:
+ cipher_str = "heh(aes)";
+ break;
default:
printk_once(KERN_WARNING
"ext4: unsupported key mode %d (ino %u)\n",
@@ -231,8 +319,7 @@ retry:
up_read(&keyring_key->sem);
goto out;
}
- res = ext4_derive_key_aes(ctx.nonce, master_key->raw,
- raw_key);
+ res = ext4_derive_key(&ctx, master_key->raw, raw_key);
up_read(&keyring_key->sem);
if (res)
goto out;
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 9f31991a5e05..8be0e4d330ab 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -589,6 +589,7 @@ enum {
#define EXT4_ENCRYPTION_MODE_AES_256_GCM 2
#define EXT4_ENCRYPTION_MODE_AES_256_CBC 3
#define EXT4_ENCRYPTION_MODE_AES_256_CTS 4
+#define EXT4_ENCRYPTION_MODE_AES_256_HEH 126
#include "ext4_crypto.h"
diff --git a/fs/ext4/ext4_crypto.h b/fs/ext4/ext4_crypto.h
index ac7d4e813796..5a1684bd083b 100644
--- a/fs/ext4/ext4_crypto.h
+++ b/fs/ext4/ext4_crypto.h
@@ -58,8 +58,10 @@ struct ext4_encryption_context {
#define EXT4_XTS_TWEAK_SIZE 16
#define EXT4_AES_128_ECB_KEY_SIZE 16
#define EXT4_AES_256_GCM_KEY_SIZE 32
+#define EXT4_AES_256_ECB_KEY_SIZE 32
#define EXT4_AES_256_CBC_KEY_SIZE 32
#define EXT4_AES_256_CTS_KEY_SIZE 32
+#define EXT4_AES_256_HEH_KEY_SIZE 32
#define EXT4_AES_256_XTS_KEY_SIZE 64
#define EXT4_MAX_KEY_SIZE 64
@@ -121,6 +123,8 @@ static inline int ext4_encryption_key_size(int mode)
return EXT4_AES_256_CBC_KEY_SIZE;
case EXT4_ENCRYPTION_MODE_AES_256_CTS:
return EXT4_AES_256_CTS_KEY_SIZE;
+ case EXT4_ENCRYPTION_MODE_AES_256_HEH:
+ return EXT4_AES_256_HEH_KEY_SIZE;
default:
BUG();
}
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index 43dcaab85201..98ca2bb1b829 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -503,8 +503,16 @@ int ext4_readpage_inline(struct inode *inode, struct page *page)
return -EAGAIN;
}
- trace_android_fs_dataread_start(inode, page_offset(page), PAGE_SIZE,
- current->pid, current->comm);
+ if (trace_android_fs_dataread_start_enabled()) {
+ char *path, pathbuf[MAX_TRACE_PATHBUF_LEN];
+
+ path = android_fstrace_get_pathname(pathbuf,
+ MAX_TRACE_PATHBUF_LEN,
+ inode);
+ trace_android_fs_dataread_start(inode, page_offset(page),
+ PAGE_SIZE, current->pid,
+ path, current->comm);
+ }
/*
* Current inline data can only exist in the 1st page,
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index c33fcb4f8533..790961e33961 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1017,8 +1017,16 @@ static int ext4_write_begin(struct file *file, struct address_space *mapping,
pgoff_t index;
unsigned from, to;
- trace_android_fs_datawrite_start(inode, pos, len,
- current->pid, current->comm);
+ if (trace_android_fs_datawrite_start_enabled()) {
+ char *path, pathbuf[MAX_TRACE_PATHBUF_LEN];
+
+ path = android_fstrace_get_pathname(pathbuf,
+ MAX_TRACE_PATHBUF_LEN,
+ inode);
+ trace_android_fs_datawrite_start(inode, pos, len,
+ current->pid, path,
+ current->comm);
+ }
trace_ext4_write_begin(inode, pos, len, flags);
/*
* Reserve one block more for addition to orphan list in case
@@ -2732,8 +2740,16 @@ static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
len, flags, pagep, fsdata);
}
*fsdata = (void *)0;
- trace_android_fs_datawrite_start(inode, pos, len,
- current->pid, current->comm);
+ if (trace_android_fs_datawrite_start_enabled()) {
+ char *path, pathbuf[MAX_TRACE_PATHBUF_LEN];
+
+ path = android_fstrace_get_pathname(pathbuf,
+ MAX_TRACE_PATHBUF_LEN,
+ inode);
+ trace_android_fs_datawrite_start(inode, pos, len,
+ current->pid,
+ path, current->comm);
+ }
trace_ext4_da_write_begin(inode, pos, len, flags);
if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
@@ -3342,16 +3358,27 @@ static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
return 0;
if (trace_android_fs_dataread_start_enabled() &&
- (iov_iter_rw(iter) == READ))
+ (iov_iter_rw(iter) == READ)) {
+ char *path, pathbuf[MAX_TRACE_PATHBUF_LEN];
+
+ path = android_fstrace_get_pathname(pathbuf,
+ MAX_TRACE_PATHBUF_LEN,
+ inode);
trace_android_fs_dataread_start(inode, offset, count,
- current->pid,
+ current->pid, path,
current->comm);
+ }
if (trace_android_fs_datawrite_start_enabled() &&
- (iov_iter_rw(iter) == WRITE))
+ (iov_iter_rw(iter) == WRITE)) {
+ char *path, pathbuf[MAX_TRACE_PATHBUF_LEN];
+
+ path = android_fstrace_get_pathname(pathbuf,
+ MAX_TRACE_PATHBUF_LEN,
+ inode);
trace_android_fs_datawrite_start(inode, offset, count,
- current->pid,
+ current->pid, path,
current->comm);
-
+ }
trace_ext4_direct_IO_enter(inode, offset, count, iov_iter_rw(iter));
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
ret = ext4_ext_direct_IO(iocb, iter, offset);
@@ -3587,6 +3614,11 @@ static int ext4_block_truncate_page(handle_t *handle,
unsigned blocksize;
struct inode *inode = mapping->host;
+ /* If we are processing an encrypted inode during orphan list
+ * handling */
+ if (ext4_encrypted_inode(inode) && !ext4_has_encryption_key(inode))
+ return 0;
+
blocksize = inode->i_sb->s_blocksize;
length = blocksize - (offset & (blocksize - 1));
diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index 1ce24a6759a0..1c5db9fd9c8f 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -152,11 +152,17 @@ ext4_submit_bio_read(struct bio *bio)
struct page *first_page = bio->bi_io_vec[0].bv_page;
if (first_page != NULL) {
+ char *path, pathbuf[MAX_TRACE_PATHBUF_LEN];
+
+ path = android_fstrace_get_pathname(pathbuf,
+ MAX_TRACE_PATHBUF_LEN,
+ first_page->mapping->host);
trace_android_fs_dataread_start(
first_page->mapping->host,
page_offset(first_page),
bio->bi_iter.bi_size,
current->pid,
+ path,
current->comm);
}
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-11 09:37:17 +0000