Merge Linus master into drm-next

The merge is clean, but the arm build fails afterwards,
due to API changes in the regulator tree.

I've included the patch into the merge to fix the build.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 194 insertions, 0 deletions

diff --git a/fs/ext4/crypto_policy.c b/fs/ext4/crypto_policy.c
new file mode 100644
index 000000000000..30eaf9e9864a
--- /dev/null
+++ b/fs/ext4/crypto_policy.c
@@ -0,0 +1,194 @@
+/*
+ * linux/fs/ext4/crypto_policy.c
+ *
+ * Copyright (C) 2015, Google, Inc.
+ *
+ * This contains encryption policy functions for ext4
+ *
+ * Written by Michael Halcrow, 2015.
+ */
+
+#include <linux/random.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include "ext4.h"
+#include "xattr.h"
+
+static int ext4_inode_has_encryption_context(struct inode *inode)
+{
+	int res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
+				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, NULL, 0);
+	return (res > 0);
+}
+
+/*
+ * check whether the policy is consistent with the encryption context
+ * for the inode
+ */
+static int ext4_is_encryption_context_consistent_with_policy(
+	struct inode *inode, const struct ext4_encryption_policy *policy)
+{
+	struct ext4_encryption_context ctx;
+	int res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
+				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
+				 sizeof(ctx));
+	if (res != sizeof(ctx))
+		return 0;
+	return (memcmp(ctx.master_key_descriptor, policy->master_key_descriptor,
+			EXT4_KEY_DESCRIPTOR_SIZE) == 0 &&
+		(ctx.contents_encryption_mode ==
+		 policy->contents_encryption_mode) &&
+		(ctx.filenames_encryption_mode ==
+		 policy->filenames_encryption_mode));
+}
+
+static int ext4_create_encryption_context_from_policy(
+	struct inode *inode, const struct ext4_encryption_policy *policy)
+{
+	struct ext4_encryption_context ctx;
+	int res = 0;
+
+	ctx.format = EXT4_ENCRYPTION_CONTEXT_FORMAT_V1;
+	memcpy(ctx.master_key_descriptor, policy->master_key_descriptor,
+	       EXT4_KEY_DESCRIPTOR_SIZE);
+	if (!ext4_valid_contents_enc_mode(policy->contents_encryption_mode)) {
+		printk(KERN_WARNING
+		       "%s: Invalid contents encryption mode %d\n", __func__,
+			policy->contents_encryption_mode);
+		res = -EINVAL;
+		goto out;
+	}
+	if (!ext4_valid_filenames_enc_mode(policy->filenames_encryption_mode)) {
+		printk(KERN_WARNING
+		       "%s: Invalid filenames encryption mode %d\n", __func__,
+			policy->filenames_encryption_mode);
+		res = -EINVAL;
+		goto out;
+	}
+	ctx.contents_encryption_mode = policy->contents_encryption_mode;
+	ctx.filenames_encryption_mode = policy->filenames_encryption_mode;
+	BUILD_BUG_ON(sizeof(ctx.nonce) != EXT4_KEY_DERIVATION_NONCE_SIZE);
+	get_random_bytes(ctx.nonce, EXT4_KEY_DERIVATION_NONCE_SIZE);
+
+	res = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION,
+			     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
+			     sizeof(ctx), 0);
+out:
+	if (!res)
+		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
+	return res;
+}
+
+int ext4_process_policy(const struct ext4_encryption_policy *policy,
+			struct inode *inode)
+{
+	if (policy->version != 0)
+		return -EINVAL;
+
+	if (!ext4_inode_has_encryption_context(inode)) {
+		if (!ext4_empty_dir(inode))
+			return -ENOTEMPTY;
+		return ext4_create_encryption_context_from_policy(inode,
+								  policy);
+	}
+
+	if (ext4_is_encryption_context_consistent_with_policy(inode, policy))
+		return 0;
+
+	printk(KERN_WARNING "%s: Policy inconsistent with encryption context\n",
+	       __func__);
+	return -EINVAL;
+}
+
+int ext4_get_policy(struct inode *inode, struct ext4_encryption_policy *policy)
+{
+	struct ext4_encryption_context ctx;
+
+	int res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
+				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
+				 &ctx, sizeof(ctx));
+	if (res != sizeof(ctx))
+		return -ENOENT;
+	if (ctx.format != EXT4_ENCRYPTION_CONTEXT_FORMAT_V1)
+		return -EINVAL;
+	policy->version = 0;
+	policy->contents_encryption_mode = ctx.contents_encryption_mode;
+	policy->filenames_encryption_mode = ctx.filenames_encryption_mode;
+	memcpy(&policy->master_key_descriptor, ctx.master_key_descriptor,
+	       EXT4_KEY_DESCRIPTOR_SIZE);
+	return 0;
+}
+
+int ext4_is_child_context_consistent_with_parent(struct inode *parent,
+						 struct inode *child)
+{
+	struct ext4_encryption_context parent_ctx, child_ctx;
+	int res;
+
+	if ((parent == NULL) || (child == NULL)) {
+		pr_err("parent %p child %p\n", parent, child);
+		BUG_ON(1);
+	}
+	/* no restrictions if the parent directory is not encrypted */
+	if (!ext4_encrypted_inode(parent))
+		return 1;
+	res = ext4_xattr_get(parent, EXT4_XATTR_INDEX_ENCRYPTION,
+			     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
+			     &parent_ctx, sizeof(parent_ctx));
+	if (res != sizeof(parent_ctx))
+		return 0;
+	/* if the child directory is not encrypted, this is always a problem */
+	if (!ext4_encrypted_inode(child))
+		return 0;
+	res = ext4_xattr_get(child, EXT4_XATTR_INDEX_ENCRYPTION,
+			     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
+			     &child_ctx, sizeof(child_ctx));
+	if (res != sizeof(child_ctx))
+		return 0;
+	return (memcmp(parent_ctx.master_key_descriptor,
+		       child_ctx.master_key_descriptor,
+		       EXT4_KEY_DESCRIPTOR_SIZE) == 0 &&
+		(parent_ctx.contents_encryption_mode ==
+		 child_ctx.contents_encryption_mode) &&
+		(parent_ctx.filenames_encryption_mode ==
+		 child_ctx.filenames_encryption_mode));
+}
+
+/**
+ * ext4_inherit_context() - Sets a child context from its parent
+ * @parent: Parent inode from which the context is inherited.
+ * @child:  Child inode that inherits the context from @parent.
+ *
+ * Return: Zero on success, non-zero otherwise
+ */
+int ext4_inherit_context(struct inode *parent, struct inode *child)
+{
+	struct ext4_encryption_context ctx;
+	int res = ext4_xattr_get(parent, EXT4_XATTR_INDEX_ENCRYPTION,
+				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
+				 &ctx, sizeof(ctx));
+
+	if (res != sizeof(ctx)) {
+		if (DUMMY_ENCRYPTION_ENABLED(EXT4_SB(parent->i_sb))) {
+			ctx.format = EXT4_ENCRYPTION_CONTEXT_FORMAT_V1;
+			ctx.contents_encryption_mode =
+				EXT4_ENCRYPTION_MODE_AES_256_XTS;
+			ctx.filenames_encryption_mode =
+				EXT4_ENCRYPTION_MODE_AES_256_CTS;
+			memset(ctx.master_key_descriptor, 0x42,
+			       EXT4_KEY_DESCRIPTOR_SIZE);
+			res = 0;
+		} else {
+			goto out;
+		}
+	}
+	get_random_bytes(ctx.nonce, EXT4_KEY_DERIVATION_NONCE_SIZE);
+	res = ext4_xattr_set(child, EXT4_XATTR_INDEX_ENCRYPTION,
+			     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
+			     sizeof(ctx), 0);
+out:
+	if (!res)
+		ext4_set_inode_flag(child, EXT4_INODE_ENCRYPT);
+	return res;
+}