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-rw-r--r--fs/crypto/crypto.c51
-rw-r--r--fs/crypto/keyinfo.c120
2 files changed, 108 insertions, 63 deletions
diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index 7f5804537d30..2fc8c43ce531 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -26,6 +26,7 @@
#include <linux/ratelimit.h>
#include <linux/bio.h>
#include <linux/dcache.h>
+#include <linux/namei.h>
#include <linux/fscrypto.h>
#include <linux/ecryptfs.h>
@@ -81,13 +82,14 @@ EXPORT_SYMBOL(fscrypt_release_ctx);
/**
* fscrypt_get_ctx() - Gets an encryption context
* @inode: The inode for which we are doing the crypto
+ * @gfp_flags: The gfp flag for memory allocation
*
* Allocates and initializes an encryption context.
*
* Return: An allocated and initialized encryption context on success; error
* value or NULL otherwise.
*/
-struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode)
+struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode, gfp_t gfp_flags)
{
struct fscrypt_ctx *ctx = NULL;
struct fscrypt_info *ci = inode->i_crypt_info;
@@ -113,7 +115,7 @@ struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode)
list_del(&ctx->free_list);
spin_unlock_irqrestore(&fscrypt_ctx_lock, flags);
if (!ctx) {
- ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, GFP_NOFS);
+ ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, gfp_flags);
if (!ctx)
return ERR_PTR(-ENOMEM);
ctx->flags |= FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
@@ -147,7 +149,8 @@ typedef enum {
static int do_page_crypto(struct inode *inode,
fscrypt_direction_t rw, pgoff_t index,
- struct page *src_page, struct page *dest_page)
+ struct page *src_page, struct page *dest_page,
+ gfp_t gfp_flags)
{
u8 xts_tweak[FS_XTS_TWEAK_SIZE];
struct skcipher_request *req = NULL;
@@ -157,7 +160,7 @@ static int do_page_crypto(struct inode *inode,
struct crypto_skcipher *tfm = ci->ci_ctfm;
int res = 0;
- req = skcipher_request_alloc(tfm, GFP_NOFS);
+ req = skcipher_request_alloc(tfm, gfp_flags);
if (!req) {
printk_ratelimited(KERN_ERR
"%s: crypto_request_alloc() failed\n",
@@ -199,10 +202,9 @@ static int do_page_crypto(struct inode *inode,
return 0;
}
-static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx)
+static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx, gfp_t gfp_flags)
{
- ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool,
- GFP_NOWAIT);
+ ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool, gfp_flags);
if (ctx->w.bounce_page == NULL)
return ERR_PTR(-ENOMEM);
ctx->flags |= FS_WRITE_PATH_FL;
@@ -213,6 +215,7 @@ static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx)
* fscypt_encrypt_page() - Encrypts a page
* @inode: The inode for which the encryption should take place
* @plaintext_page: The page to encrypt. Must be locked.
+ * @gfp_flags: The gfp flag for memory allocation
*
* Allocates a ciphertext page and encrypts plaintext_page into it using the ctx
* encryption context.
@@ -225,7 +228,7 @@ static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx)
* error value or NULL.
*/
struct page *fscrypt_encrypt_page(struct inode *inode,
- struct page *plaintext_page)
+ struct page *plaintext_page, gfp_t gfp_flags)
{
struct fscrypt_ctx *ctx;
struct page *ciphertext_page = NULL;
@@ -233,18 +236,19 @@ struct page *fscrypt_encrypt_page(struct inode *inode,
BUG_ON(!PageLocked(plaintext_page));
- ctx = fscrypt_get_ctx(inode);
+ ctx = fscrypt_get_ctx(inode, gfp_flags);
if (IS_ERR(ctx))
return (struct page *)ctx;
/* The encryption operation will require a bounce page. */
- ciphertext_page = alloc_bounce_page(ctx);
+ ciphertext_page = alloc_bounce_page(ctx, gfp_flags);
if (IS_ERR(ciphertext_page))
goto errout;
ctx->w.control_page = plaintext_page;
err = do_page_crypto(inode, FS_ENCRYPT, plaintext_page->index,
- plaintext_page, ciphertext_page);
+ plaintext_page, ciphertext_page,
+ gfp_flags);
if (err) {
ciphertext_page = ERR_PTR(err);
goto errout;
@@ -275,7 +279,7 @@ int fscrypt_decrypt_page(struct page *page)
BUG_ON(!PageLocked(page));
return do_page_crypto(page->mapping->host,
- FS_DECRYPT, page->index, page, page);
+ FS_DECRYPT, page->index, page, page, GFP_NOFS);
}
EXPORT_SYMBOL(fscrypt_decrypt_page);
@@ -289,11 +293,11 @@ int fscrypt_zeroout_range(struct inode *inode, pgoff_t lblk,
BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE);
- ctx = fscrypt_get_ctx(inode);
+ ctx = fscrypt_get_ctx(inode, GFP_NOFS);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
- ciphertext_page = alloc_bounce_page(ctx);
+ ciphertext_page = alloc_bounce_page(ctx, GFP_NOWAIT);
if (IS_ERR(ciphertext_page)) {
err = PTR_ERR(ciphertext_page);
goto errout;
@@ -301,11 +305,12 @@ int fscrypt_zeroout_range(struct inode *inode, pgoff_t lblk,
while (len--) {
err = do_page_crypto(inode, FS_ENCRYPT, lblk,
- ZERO_PAGE(0), ciphertext_page);
+ ZERO_PAGE(0), ciphertext_page,
+ GFP_NOFS);
if (err)
goto errout;
- bio = bio_alloc(GFP_KERNEL, 1);
+ bio = bio_alloc(GFP_NOWAIT, 1);
if (!bio) {
err = -ENOMEM;
goto errout;
@@ -345,13 +350,20 @@ EXPORT_SYMBOL(fscrypt_zeroout_range);
*/
static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
{
- struct inode *dir = d_inode(dentry->d_parent);
- struct fscrypt_info *ci = dir->i_crypt_info;
+ struct dentry *dir;
+ struct fscrypt_info *ci;
int dir_has_key, cached_with_key;
- if (!dir->i_sb->s_cop->is_encrypted(dir))
+ if (flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ dir = dget_parent(dentry);
+ if (!d_inode(dir)->i_sb->s_cop->is_encrypted(d_inode(dir))) {
+ dput(dir);
return 0;
+ }
+ ci = d_inode(dir)->i_crypt_info;
if (ci && ci->ci_keyring_key &&
(ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
(1 << KEY_FLAG_REVOKED) |
@@ -363,6 +375,7 @@ static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
cached_with_key = dentry->d_flags & DCACHE_ENCRYPTED_WITH_KEY;
spin_unlock(&dentry->d_lock);
dir_has_key = (ci != NULL);
+ dput(dir);
/*
* If the dentry was cached without the key, and it is a
diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
index 06f5aa478bf2..1ac263eddc4e 100644
--- a/fs/crypto/keyinfo.c
+++ b/fs/crypto/keyinfo.c
@@ -78,6 +78,67 @@ out:
return res;
}
+static int validate_user_key(struct fscrypt_info *crypt_info,
+ struct fscrypt_context *ctx, u8 *raw_key,
+ u8 *prefix, int prefix_size)
+{
+ u8 *full_key_descriptor;
+ 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)
+ 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);
+ if (IS_ERR(keyring_key))
+ return PTR_ERR(keyring_key);
+
+ if (keyring_key->type != &key_type_logon) {
+ printk_once(KERN_WARNING
+ "%s: key type must be logon\n", __func__);
+ res = -ENOKEY;
+ goto out;
+ }
+ down_read(&keyring_key->sem);
+ ukp = user_key_payload(keyring_key);
+ if (ukp->datalen != sizeof(struct fscrypt_key)) {
+ res = -EINVAL;
+ up_read(&keyring_key->sem);
+ goto out;
+ }
+ 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) {
+ printk_once(KERN_WARNING
+ "%s: key size incorrect: %d\n",
+ __func__, master_key->size);
+ res = -ENOKEY;
+ up_read(&keyring_key->sem);
+ goto out;
+ }
+ res = derive_key_aes(ctx->nonce, master_key->raw, raw_key);
+ up_read(&keyring_key->sem);
+ if (res)
+ goto out;
+
+ crypt_info->ci_keyring_key = keyring_key;
+ return 0;
+out:
+ key_put(keyring_key);
+ return res;
+}
+
static void put_crypt_info(struct fscrypt_info *ci)
{
if (!ci)
@@ -91,12 +152,7 @@ static void put_crypt_info(struct fscrypt_info *ci)
int get_crypt_info(struct inode *inode)
{
struct fscrypt_info *crypt_info;
- u8 full_key_descriptor[FS_KEY_DESC_PREFIX_SIZE +
- (FS_KEY_DESCRIPTOR_SIZE * 2) + 1];
- struct key *keyring_key = NULL;
- struct fscrypt_key *master_key;
struct fscrypt_context ctx;
- const struct user_key_payload *ukp;
struct crypto_skcipher *ctfm;
const char *cipher_str;
u8 raw_key[FS_MAX_KEY_SIZE];
@@ -167,48 +223,24 @@ retry:
memset(raw_key, 0x42, FS_AES_256_XTS_KEY_SIZE);
goto got_key;
}
- memcpy(full_key_descriptor, FS_KEY_DESC_PREFIX,
- FS_KEY_DESC_PREFIX_SIZE);
- sprintf(full_key_descriptor + FS_KEY_DESC_PREFIX_SIZE,
- "%*phN", FS_KEY_DESCRIPTOR_SIZE,
- ctx.master_key_descriptor);
- full_key_descriptor[FS_KEY_DESC_PREFIX_SIZE +
- (2 * FS_KEY_DESCRIPTOR_SIZE)] = '\0';
- keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL);
- if (IS_ERR(keyring_key)) {
- res = PTR_ERR(keyring_key);
- keyring_key = NULL;
- goto out;
- }
- crypt_info->ci_keyring_key = keyring_key;
- if (keyring_key->type != &key_type_logon) {
- printk_once(KERN_WARNING
- "%s: key type must be logon\n", __func__);
- res = -ENOKEY;
- goto out;
- }
- down_read(&keyring_key->sem);
- ukp = user_key_payload(keyring_key);
- if (ukp->datalen != sizeof(struct fscrypt_key)) {
- res = -EINVAL;
- up_read(&keyring_key->sem);
- goto out;
- }
- 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) {
- printk_once(KERN_WARNING
- "%s: key size incorrect: %d\n",
- __func__, master_key->size);
- res = -ENOKEY;
- up_read(&keyring_key->sem);
+ res = validate_user_key(crypt_info, &ctx, raw_key,
+ FS_KEY_DESC_PREFIX, FS_KEY_DESC_PREFIX_SIZE);
+ 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);
+ if (res2) {
+ if (res2 == -ENOKEY)
+ res = -ENOKEY;
+ goto out;
+ }
+ } else if (res) {
goto out;
}
- res = derive_key_aes(ctx.nonce, master_key->raw, raw_key);
- up_read(&keyring_key->sem);
- if (res)
- goto out;
got_key:
ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
if (!ctfm || IS_ERR(ctfm)) {
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