diff options
Diffstat (limited to 'fs/crypto/policy.c')
| -rw-r--r-- | fs/crypto/policy.c | 35 |
1 files changed, 29 insertions, 6 deletions
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c index 8a054e6d1e68..80b8ca0f340b 100644 --- a/fs/crypto/policy.c +++ b/fs/crypto/policy.c @@ -694,6 +694,32 @@ const union fscrypt_policy *fscrypt_policy_to_inherit(struct inode *dir) } /** + * fscrypt_context_for_new_inode() - create an encryption context for a new inode + * @ctx: where context should be written + * @inode: inode from which to fetch policy and nonce + * + * Given an in-core "prepared" (via fscrypt_prepare_new_inode) inode, + * generate a new context and write it to ctx. ctx _must_ be at least + * FSCRYPT_SET_CONTEXT_MAX_SIZE bytes. + * + * Return: size of the resulting context or a negative error code. + */ +int fscrypt_context_for_new_inode(void *ctx, struct inode *inode) +{ + struct fscrypt_info *ci = inode->i_crypt_info; + + BUILD_BUG_ON(sizeof(union fscrypt_context) != + FSCRYPT_SET_CONTEXT_MAX_SIZE); + + /* fscrypt_prepare_new_inode() should have set up the key already. */ + if (WARN_ON_ONCE(!ci)) + return -ENOKEY; + + return fscrypt_new_context(ctx, &ci->ci_policy, ci->ci_nonce); +} +EXPORT_SYMBOL_GPL(fscrypt_context_for_new_inode); + +/** * fscrypt_set_context() - Set the fscrypt context of a new inode * @inode: a new inode * @fs_data: private data given by FS and passed to ->set_context() @@ -709,12 +735,9 @@ int fscrypt_set_context(struct inode *inode, void *fs_data) union fscrypt_context ctx; int ctxsize; - /* fscrypt_prepare_new_inode() should have set up the key already. */ - if (WARN_ON_ONCE(!ci)) - return -ENOKEY; - - BUILD_BUG_ON(sizeof(ctx) != FSCRYPT_SET_CONTEXT_MAX_SIZE); - ctxsize = fscrypt_new_context(&ctx, &ci->ci_policy, ci->ci_nonce); + ctxsize = fscrypt_context_for_new_inode(&ctx, inode); + if (ctxsize < 0) + return ctxsize; /* * This may be the first time the inode number is available, so do any |