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-rw-r--r--fs/crypto/crypto.c11
-rw-r--r--fs/crypto/fname.c85
-rw-r--r--fs/crypto/keyinfo.c71
3 files changed, 93 insertions, 74 deletions
diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index c502c116924c..61057b7dbddb 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -28,7 +28,6 @@
#include <linux/dcache.h>
#include <linux/namei.h>
#include <linux/fscrypto.h>
-#include <linux/ecryptfs.h>
static unsigned int num_prealloc_crypto_pages = 32;
static unsigned int num_prealloc_crypto_ctxs = 128;
@@ -128,11 +127,11 @@ struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode, gfp_t gfp_flags)
EXPORT_SYMBOL(fscrypt_get_ctx);
/**
- * fscrypt_complete() - The completion callback for page encryption
- * @req: The asynchronous encryption request context
- * @res: The result of the encryption operation
+ * page_crypt_complete() - completion callback for page crypto
+ * @req: The asynchronous cipher request context
+ * @res: The result of the cipher operation
*/
-static void fscrypt_complete(struct crypto_async_request *req, int res)
+static void page_crypt_complete(struct crypto_async_request *req, int res)
{
struct fscrypt_completion_result *ecr = req->data;
@@ -170,7 +169,7 @@ static int do_page_crypto(struct inode *inode,
skcipher_request_set_callback(
req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
- fscrypt_complete, &ecr);
+ page_crypt_complete, &ecr);
BUILD_BUG_ON(FS_XTS_TWEAK_SIZE < sizeof(index));
memcpy(xts_tweak, &index, sizeof(index));
diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 5d6d49113efa..9a28133ac3b8 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -10,21 +10,16 @@
* This has not yet undergone a rigorous security audit.
*/
-#include <keys/encrypted-type.h>
-#include <keys/user-type.h>
#include <linux/scatterlist.h>
#include <linux/ratelimit.h>
#include <linux/fscrypto.h>
-static u32 size_round_up(size_t size, size_t blksize)
-{
- return ((size + blksize - 1) / blksize) * blksize;
-}
-
/**
- * dir_crypt_complete() -
+ * fname_crypt_complete() - completion callback for filename crypto
+ * @req: The asynchronous cipher request context
+ * @res: The result of the cipher operation
*/
-static void dir_crypt_complete(struct crypto_async_request *req, int res)
+static void fname_crypt_complete(struct crypto_async_request *req, int res)
{
struct fscrypt_completion_result *ecr = req->data;
@@ -35,11 +30,11 @@ static void dir_crypt_complete(struct crypto_async_request *req, int res)
}
/**
- * fname_encrypt() -
+ * fname_encrypt() - encrypt a filename
*
- * This function encrypts the input filename, and returns the length of the
- * ciphertext. Errors are returned as negative numbers. We trust the caller to
- * allocate sufficient memory to oname string.
+ * The caller must have allocated sufficient memory for the @oname string.
+ *
+ * Return: 0 on success, -errno on failure
*/
static int fname_encrypt(struct inode *inode,
const struct qstr *iname, struct fscrypt_str *oname)
@@ -60,10 +55,9 @@ static int fname_encrypt(struct inode *inode,
if (iname->len <= 0 || iname->len > lim)
return -EIO;
- ciphertext_len = (iname->len < FS_CRYPTO_BLOCK_SIZE) ?
- FS_CRYPTO_BLOCK_SIZE : iname->len;
- ciphertext_len = size_round_up(ciphertext_len, padding);
- ciphertext_len = (ciphertext_len > lim) ? lim : ciphertext_len;
+ ciphertext_len = max(iname->len, (u32)FS_CRYPTO_BLOCK_SIZE);
+ ciphertext_len = round_up(ciphertext_len, padding);
+ ciphertext_len = min(ciphertext_len, lim);
if (ciphertext_len <= sizeof(buf)) {
workbuf = buf;
@@ -84,7 +78,7 @@ static int fname_encrypt(struct inode *inode,
}
skcipher_request_set_callback(req,
CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
- dir_crypt_complete, &ecr);
+ fname_crypt_complete, &ecr);
/* Copy the input */
memcpy(workbuf, iname->name, iname->len);
@@ -105,20 +99,22 @@ static int fname_encrypt(struct inode *inode,
}
kfree(alloc_buf);
skcipher_request_free(req);
- if (res < 0)
+ if (res < 0) {
printk_ratelimited(KERN_ERR
"%s: Error (error code %d)\n", __func__, res);
+ return res;
+ }
oname->len = ciphertext_len;
- return res;
+ return 0;
}
-/*
- * fname_decrypt()
- * This function decrypts the input filename, and returns
- * the length of the plaintext.
- * Errors are returned as negative numbers.
- * We trust the caller to allocate sufficient memory to oname string.
+/**
+ * fname_decrypt() - decrypt a filename
+ *
+ * The caller must have allocated sufficient memory for the @oname string.
+ *
+ * Return: 0 on success, -errno on failure
*/
static int fname_decrypt(struct inode *inode,
const struct fscrypt_str *iname,
@@ -146,7 +142,7 @@ static int fname_decrypt(struct inode *inode,
}
skcipher_request_set_callback(req,
CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
- dir_crypt_complete, &ecr);
+ fname_crypt_complete, &ecr);
/* Initialize IV */
memset(iv, 0, FS_CRYPTO_BLOCK_SIZE);
@@ -168,7 +164,7 @@ static int fname_decrypt(struct inode *inode,
}
oname->len = strnlen(oname->name, iname->len);
- return oname->len;
+ return 0;
}
static const char *lookup_table =
@@ -231,9 +227,8 @@ u32 fscrypt_fname_encrypted_size(struct inode *inode, u32 ilen)
if (ci)
padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK);
- if (ilen < FS_CRYPTO_BLOCK_SIZE)
- ilen = FS_CRYPTO_BLOCK_SIZE;
- return size_round_up(ilen, padding);
+ ilen = max(ilen, (u32)FS_CRYPTO_BLOCK_SIZE);
+ return round_up(ilen, padding);
}
EXPORT_SYMBOL(fscrypt_fname_encrypted_size);
@@ -279,6 +274,10 @@ EXPORT_SYMBOL(fscrypt_fname_free_buffer);
/**
* fscrypt_fname_disk_to_usr() - converts a filename from disk space to user
* space
+ *
+ * The caller must have allocated sufficient memory for the @oname string.
+ *
+ * Return: 0 on success, -errno on failure
*/
int fscrypt_fname_disk_to_usr(struct inode *inode,
u32 hash, u32 minor_hash,
@@ -287,13 +286,12 @@ int fscrypt_fname_disk_to_usr(struct inode *inode,
{
const struct qstr qname = FSTR_TO_QSTR(iname);
char buf[24];
- int ret;
if (fscrypt_is_dot_dotdot(&qname)) {
oname->name[0] = '.';
oname->name[iname->len - 1] = '.';
oname->len = iname->len;
- return oname->len;
+ return 0;
}
if (iname->len < FS_CRYPTO_BLOCK_SIZE)
@@ -303,9 +301,9 @@ int fscrypt_fname_disk_to_usr(struct inode *inode,
return fname_decrypt(inode, iname, oname);
if (iname->len <= FS_FNAME_CRYPTO_DIGEST_SIZE) {
- ret = digest_encode(iname->name, iname->len, oname->name);
- oname->len = ret;
- return ret;
+ oname->len = digest_encode(iname->name, iname->len,
+ oname->name);
+ return 0;
}
if (hash) {
memcpy(buf, &hash, 4);
@@ -315,15 +313,18 @@ int fscrypt_fname_disk_to_usr(struct inode *inode,
}
memcpy(buf + 8, iname->name + iname->len - 16, 16);
oname->name[0] = '_';
- ret = digest_encode(buf, 24, oname->name + 1);
- oname->len = ret + 1;
- return ret + 1;
+ oname->len = 1 + digest_encode(buf, 24, oname->name + 1);
+ return 0;
}
EXPORT_SYMBOL(fscrypt_fname_disk_to_usr);
/**
* fscrypt_fname_usr_to_disk() - converts a filename from user space to disk
* space
+ *
+ * The caller must have allocated sufficient memory for the @oname string.
+ *
+ * Return: 0 on success, -errno on failure
*/
int fscrypt_fname_usr_to_disk(struct inode *inode,
const struct qstr *iname,
@@ -333,7 +334,7 @@ int fscrypt_fname_usr_to_disk(struct inode *inode,
oname->name[0] = '.';
oname->name[iname->len - 1] = '.';
oname->len = iname->len;
- return oname->len;
+ return 0;
}
if (inode->i_crypt_info)
return fname_encrypt(inode, iname, oname);
@@ -367,10 +368,10 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
if (dir->i_crypt_info) {
ret = fscrypt_fname_alloc_buffer(dir, iname->len,
&fname->crypto_buf);
- if (ret < 0)
+ if (ret)
return ret;
ret = fname_encrypt(dir, iname, &fname->crypto_buf);
- if (ret < 0)
+ if (ret)
goto errout;
fname->disk_name.name = fname->crypto_buf.name;
fname->disk_name.len = fname->crypto_buf.len;
diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
index 1ac263eddc4e..82f0285f5d08 100644
--- a/fs/crypto/keyinfo.c
+++ b/fs/crypto/keyinfo.c
@@ -8,11 +8,8 @@
* Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
*/
-#include <keys/encrypted-type.h>
#include <keys/user-type.h>
-#include <linux/random.h>
#include <linux/scatterlist.h>
-#include <uapi/linux/keyctl.h>
#include <linux/fscrypto.h>
static void derive_crypt_complete(struct crypto_async_request *req, int rc)
@@ -139,6 +136,38 @@ out:
return res;
}
+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;
+ }
+
+ 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;
+ }
+
+ pr_warn_once("fscrypto: unsupported file type %d for inode %lu\n",
+ (inode->i_mode & S_IFMT), inode->i_ino);
+ return -ENOKEY;
+}
+
static void put_crypt_info(struct fscrypt_info *ci)
{
if (!ci)
@@ -155,8 +184,8 @@ int get_crypt_info(struct inode *inode)
struct fscrypt_context ctx;
struct crypto_skcipher *ctfm;
const char *cipher_str;
+ int keysize;
u8 raw_key[FS_MAX_KEY_SIZE];
- u8 mode;
int res;
res = fscrypt_initialize();
@@ -179,13 +208,19 @@ retry:
if (res < 0) {
if (!fscrypt_dummy_context_enabled(inode))
return res;
+ 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;
} else if (res != sizeof(ctx)) {
return -EINVAL;
}
- res = 0;
+
+ if (ctx.format != FS_ENCRYPTION_CONTEXT_FORMAT_V1)
+ return -EINVAL;
+
+ if (ctx.flags & ~FS_POLICY_FLAGS_VALID)
+ return -EINVAL;
crypt_info = kmem_cache_alloc(fscrypt_info_cachep, GFP_NOFS);
if (!crypt_info)
@@ -198,27 +233,11 @@ retry:
crypt_info->ci_keyring_key = NULL;
memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor,
sizeof(crypt_info->ci_master_key));
- if (S_ISREG(inode->i_mode))
- mode = crypt_info->ci_data_mode;
- else if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
- mode = crypt_info->ci_filename_mode;
- else
- BUG();
-
- switch (mode) {
- case FS_ENCRYPTION_MODE_AES_256_XTS:
- cipher_str = "xts(aes)";
- break;
- case FS_ENCRYPTION_MODE_AES_256_CTS:
- cipher_str = "cts(cbc(aes))";
- break;
- default:
- printk_once(KERN_WARNING
- "%s: unsupported key mode %d (ino %u)\n",
- __func__, mode, (unsigned) inode->i_ino);
- res = -ENOKEY;
+
+ res = determine_cipher_type(crypt_info, inode, &cipher_str, &keysize);
+ if (res)
goto out;
- }
+
if (fscrypt_dummy_context_enabled(inode)) {
memset(raw_key, 0x42, FS_AES_256_XTS_KEY_SIZE);
goto got_key;
@@ -253,7 +272,7 @@ got_key:
crypt_info->ci_ctfm = ctfm;
crypto_skcipher_clear_flags(ctfm, ~0);
crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_REQ_WEAK_KEY);
- res = crypto_skcipher_setkey(ctfm, raw_key, fscrypt_key_size(mode));
+ res = crypto_skcipher_setkey(ctfm, raw_key, keysize);
if (res)
goto out;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-19 20:48:19 +0000