diff options
Diffstat (limited to 'fs/ext4/crypto.c')
| -rw-r--r-- | fs/ext4/crypto.c | 80 |
1 files changed, 67 insertions, 13 deletions
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c index c8021208a7eb..edc053a81914 100644 --- a/fs/ext4/crypto.c +++ b/fs/ext4/crypto.c @@ -18,11 +18,9 @@ * Special Publication 800-38E and IEEE P1619/D16. */ -#include <crypto/hash.h> -#include <crypto/sha.h> +#include <crypto/skcipher.h> #include <keys/user-type.h> #include <keys/encrypted-type.h> -#include <linux/crypto.h> #include <linux/ecryptfs.h> #include <linux/gfp.h> #include <linux/kernel.h> @@ -261,21 +259,21 @@ static int ext4_page_crypto(struct inode *inode, { u8 xts_tweak[EXT4_XTS_TWEAK_SIZE]; - struct ablkcipher_request *req = NULL; + struct skcipher_request *req = NULL; DECLARE_EXT4_COMPLETION_RESULT(ecr); struct scatterlist dst, src; struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info; - struct crypto_ablkcipher *tfm = ci->ci_ctfm; + struct crypto_skcipher *tfm = ci->ci_ctfm; int res = 0; - req = ablkcipher_request_alloc(tfm, GFP_NOFS); + req = skcipher_request_alloc(tfm, GFP_NOFS); if (!req) { printk_ratelimited(KERN_ERR "%s: crypto_request_alloc() failed\n", __func__); return -ENOMEM; } - ablkcipher_request_set_callback( + skcipher_request_set_callback( req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, ext4_crypt_complete, &ecr); @@ -288,21 +286,21 @@ static int ext4_page_crypto(struct inode *inode, sg_set_page(&dst, dest_page, PAGE_CACHE_SIZE, 0); sg_init_table(&src, 1); sg_set_page(&src, src_page, PAGE_CACHE_SIZE, 0); - ablkcipher_request_set_crypt(req, &src, &dst, PAGE_CACHE_SIZE, - xts_tweak); + skcipher_request_set_crypt(req, &src, &dst, PAGE_CACHE_SIZE, + xts_tweak); if (rw == EXT4_DECRYPT) - res = crypto_ablkcipher_decrypt(req); + res = crypto_skcipher_decrypt(req); else - res = crypto_ablkcipher_encrypt(req); + res = crypto_skcipher_encrypt(req); if (res == -EINPROGRESS || res == -EBUSY) { wait_for_completion(&ecr.completion); res = ecr.res; } - ablkcipher_request_free(req); + skcipher_request_free(req); if (res) { printk_ratelimited( KERN_ERR - "%s: crypto_ablkcipher_encrypt() returned %d\n", + "%s: crypto_skcipher_encrypt() returned %d\n", __func__, res); return res; } @@ -467,3 +465,59 @@ uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size) return size; return 0; } + +/* + * Validate dentries for encrypted directories to make sure we aren't + * potentially caching stale data after a key has been added or + * removed. + */ +static int ext4_d_revalidate(struct dentry *dentry, unsigned int flags) +{ + struct inode *dir = d_inode(dentry->d_parent); + struct ext4_crypt_info *ci = EXT4_I(dir)->i_crypt_info; + int dir_has_key, cached_with_key; + + if (!ext4_encrypted_inode(dir)) + return 0; + + if (ci && ci->ci_keyring_key && + (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) | + (1 << KEY_FLAG_REVOKED) | + (1 << KEY_FLAG_DEAD)))) + ci = NULL; + + /* this should eventually be an flag in d_flags */ + cached_with_key = dentry->d_fsdata != NULL; + dir_has_key = (ci != NULL); + + /* + * If the dentry was cached without the key, and it is a + * negative dentry, it might be a valid name. We can't check + * if the key has since been made available due to locking + * reasons, so we fail the validation so ext4_lookup() can do + * this check. + * + * We also fail the validation if the dentry was created with + * the key present, but we no longer have the key, or vice versa. + */ + if ((!cached_with_key && d_is_negative(dentry)) || + (!cached_with_key && dir_has_key) || + (cached_with_key && !dir_has_key)) { +#if 0 /* Revalidation debug */ + char buf[80]; + char *cp = simple_dname(dentry, buf, sizeof(buf)); + + if (IS_ERR(cp)) + cp = (char *) "???"; + pr_err("revalidate: %s %p %d %d %d\n", cp, dentry->d_fsdata, + cached_with_key, d_is_negative(dentry), + dir_has_key); +#endif + return 0; + } + return 1; +} + +const struct dentry_operations ext4_encrypted_d_ops = { + .d_revalidate = ext4_d_revalidate, +}; |