[Feature] add GA346 baseline version

Change-Id: Ic62933698569507dcf98240cdf5d9931ae34348f
diff --git a/src/kernel/linux/v4.19/fs/crypto/crypto.c b/src/kernel/linux/v4.19/fs/crypto/crypto.c
new file mode 100644
index 0000000..41b4fe1
--- /dev/null
+++ b/src/kernel/linux/v4.19/fs/crypto/crypto.c
@@ -0,0 +1,429 @@
+/*
+ * This contains encryption functions for per-file encryption.
+ *
+ * Copyright (C) 2015, Google, Inc.
+ * Copyright (C) 2015, Motorola Mobility
+ *
+ * Written by Michael Halcrow, 2014.
+ *
+ * Filename encryption additions
+ *	Uday Savagaonkar, 2014
+ * Encryption policy handling additions
+ *	Ildar Muslukhov, 2014
+ * Add fscrypt_pullback_bio_page()
+ *	Jaegeuk Kim, 2015.
+ *
+ * This has not yet undergone a rigorous security audit.
+ *
+ * The usage of AES-XTS should conform to recommendations in NIST
+ * Special Publication 800-38E and IEEE P1619/D16.
+ */
+
+#include <linux/pagemap.h>
+#include <linux/mempool.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/ratelimit.h>
+#include <linux/dcache.h>
+#include <linux/namei.h>
+#include <crypto/skcipher.h>
+#include "fscrypt_private.h"
+
+static unsigned int num_prealloc_crypto_pages = 32;
+
+module_param(num_prealloc_crypto_pages, uint, 0444);
+MODULE_PARM_DESC(num_prealloc_crypto_pages,
+		"Number of crypto pages to preallocate");
+
+static mempool_t *fscrypt_bounce_page_pool = NULL;
+
+static struct workqueue_struct *fscrypt_read_workqueue;
+static DEFINE_MUTEX(fscrypt_init_mutex);
+
+struct kmem_cache *fscrypt_info_cachep;
+
+void fscrypt_enqueue_decrypt_work(struct work_struct *work)
+{
+	queue_work(fscrypt_read_workqueue, work);
+}
+EXPORT_SYMBOL(fscrypt_enqueue_decrypt_work);
+
+struct page *fscrypt_alloc_bounce_page(gfp_t gfp_flags)
+{
+	return mempool_alloc(fscrypt_bounce_page_pool, gfp_flags);
+}
+
+/**
+ * fscrypt_free_bounce_page() - free a ciphertext bounce page
+ *
+ * Free a bounce page that was allocated by fscrypt_encrypt_pagecache_blocks(),
+ * or by fscrypt_alloc_bounce_page() directly.
+ */
+void fscrypt_free_bounce_page(struct page *bounce_page)
+{
+	if (!bounce_page)
+		return;
+	set_page_private(bounce_page, (unsigned long)NULL);
+	ClearPagePrivate(bounce_page);
+	mempool_free(bounce_page, fscrypt_bounce_page_pool);
+}
+EXPORT_SYMBOL(fscrypt_free_bounce_page);
+
+void fscrypt_generate_iv(union fscrypt_iv *iv, u64 lblk_num,
+			 const struct fscrypt_info *ci)
+{
+	u8 flags = fscrypt_policy_flags(&ci->ci_policy);
+
+	memset(iv, 0, ci->ci_mode->ivsize);
+
+	if (flags & FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64) {
+		WARN_ON_ONCE((u32)lblk_num != lblk_num);
+		lblk_num |= (u64)ci->ci_inode->i_ino << 32;
+	} else if (flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY) {
+		memcpy(iv->nonce, ci->ci_nonce, FS_KEY_DERIVATION_NONCE_SIZE);
+	}
+	iv->lblk_num = cpu_to_le64(lblk_num);
+}
+
+/* Encrypt or decrypt a single filesystem block of file contents */
+int fscrypt_crypt_block(const struct inode *inode, fscrypt_direction_t rw,
+			u64 lblk_num, struct page *src_page,
+			struct page *dest_page, unsigned int len,
+			unsigned int offs, gfp_t gfp_flags)
+{
+	union fscrypt_iv iv;
+	struct skcipher_request *req = NULL;
+	DECLARE_CRYPTO_WAIT(wait);
+	struct scatterlist dst, src;
+	struct fscrypt_info *ci = inode->i_crypt_info;
+	struct crypto_skcipher *tfm = ci->ci_key.tfm;
+	int res = 0;
+
+	if (WARN_ON_ONCE(len <= 0))
+		return -EINVAL;
+	if (WARN_ON_ONCE(len % FS_CRYPTO_BLOCK_SIZE != 0))
+		return -EINVAL;
+
+	fscrypt_generate_iv(&iv, lblk_num, ci);
+
+	req = skcipher_request_alloc(tfm, gfp_flags);
+	if (!req)
+		return -ENOMEM;
+
+	skcipher_request_set_callback(
+		req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
+		crypto_req_done, &wait);
+
+	sg_init_table(&dst, 1);
+	sg_set_page(&dst, dest_page, len, offs);
+	sg_init_table(&src, 1);
+	sg_set_page(&src, src_page, len, offs);
+	skcipher_request_set_crypt(req, &src, &dst, len, &iv);
+	if (rw == FS_DECRYPT)
+		res = crypto_wait_req(crypto_skcipher_decrypt(req), &wait);
+	else
+		res = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
+	skcipher_request_free(req);
+	if (res) {
+		fscrypt_err(inode, "%scryption failed for block %llu: %d",
+			    (rw == FS_DECRYPT ? "De" : "En"), lblk_num, res);
+		return res;
+	}
+	return 0;
+}
+
+/**
+ * fscrypt_encrypt_pagecache_blocks() - Encrypt filesystem blocks from a pagecache page
+ * @page:      The locked pagecache page containing the block(s) to encrypt
+ * @len:       Total size of the block(s) to encrypt.  Must be a nonzero
+ *		multiple of the filesystem's block size.
+ * @offs:      Byte offset within @page of the first block to encrypt.  Must be
+ *		a multiple of the filesystem's block size.
+ * @gfp_flags: Memory allocation flags
+ *
+ * A new bounce page is allocated, and the specified block(s) are encrypted into
+ * it.  In the bounce page, the ciphertext block(s) will be located at the same
+ * offsets at which the plaintext block(s) were located in the source page; any
+ * other parts of the bounce page will be left uninitialized.  However, normally
+ * blocksize == PAGE_SIZE and the whole page is encrypted at once.
+ *
+ * This is for use by the filesystem's ->writepages() method.
+ *
+ * Return: the new encrypted bounce page on success; an ERR_PTR() on failure
+ */
+struct page *fscrypt_encrypt_pagecache_blocks(struct page *page,
+					      unsigned int len,
+					      unsigned int offs,
+					      gfp_t gfp_flags)
+
+{
+	const struct inode *inode = page->mapping->host;
+	const unsigned int blockbits = inode->i_blkbits;
+	const unsigned int blocksize = 1 << blockbits;
+	struct page *ciphertext_page;
+	u64 lblk_num = ((u64)page->index << (PAGE_SHIFT - blockbits)) +
+		       (offs >> blockbits);
+	unsigned int i;
+	int err;
+
+	if (WARN_ON_ONCE(!PageLocked(page)))
+		return ERR_PTR(-EINVAL);
+
+	if (WARN_ON_ONCE(len <= 0 || !IS_ALIGNED(len | offs, blocksize)))
+		return ERR_PTR(-EINVAL);
+
+	ciphertext_page = fscrypt_alloc_bounce_page(gfp_flags);
+	if (!ciphertext_page)
+		return ERR_PTR(-ENOMEM);
+
+	for (i = offs; i < offs + len; i += blocksize, lblk_num++) {
+		err = fscrypt_crypt_block(inode, FS_ENCRYPT, lblk_num,
+					  page, ciphertext_page,
+					  blocksize, i, gfp_flags);
+		if (err) {
+			fscrypt_free_bounce_page(ciphertext_page);
+			return ERR_PTR(err);
+		}
+	}
+	SetPagePrivate(ciphertext_page);
+	set_page_private(ciphertext_page, (unsigned long)page);
+	return ciphertext_page;
+}
+EXPORT_SYMBOL(fscrypt_encrypt_pagecache_blocks);
+
+/**
+ * fscrypt_encrypt_block_inplace() - Encrypt a filesystem block in-place
+ * @inode:     The inode to which this block belongs
+ * @page:      The page containing the block to encrypt
+ * @len:       Size of block to encrypt.  Doesn't need to be a multiple of the
+ *		fs block size, but must be a multiple of FS_CRYPTO_BLOCK_SIZE.
+ * @offs:      Byte offset within @page at which the block to encrypt begins
+ * @lblk_num:  Filesystem logical block number of the block, i.e. the 0-based
+ *		number of the block within the file
+ * @gfp_flags: Memory allocation flags
+ *
+ * Encrypt a possibly-compressed filesystem block that is located in an
+ * arbitrary page, not necessarily in the original pagecache page.  The @inode
+ * and @lblk_num must be specified, as they can't be determined from @page.
+ *
+ * Return: 0 on success; -errno on failure
+ */
+int fscrypt_encrypt_block_inplace(const struct inode *inode, struct page *page,
+				  unsigned int len, unsigned int offs,
+				  u64 lblk_num, gfp_t gfp_flags)
+{
+	return fscrypt_crypt_block(inode, FS_ENCRYPT, lblk_num, page, page,
+				   len, offs, gfp_flags);
+}
+EXPORT_SYMBOL(fscrypt_encrypt_block_inplace);
+
+/**
+ * fscrypt_decrypt_pagecache_blocks() - Decrypt filesystem blocks in a pagecache page
+ * @page:      The locked pagecache page containing the block(s) to decrypt
+ * @len:       Total size of the block(s) to decrypt.  Must be a nonzero
+ *		multiple of the filesystem's block size.
+ * @offs:      Byte offset within @page of the first block to decrypt.  Must be
+ *		a multiple of the filesystem's block size.
+ *
+ * The specified block(s) are decrypted in-place within the pagecache page,
+ * which must still be locked and not uptodate.  Normally, blocksize ==
+ * PAGE_SIZE and the whole page is decrypted at once.
+ *
+ * This is for use by the filesystem's ->readpages() method.
+ *
+ * Return: 0 on success; -errno on failure
+ */
+int fscrypt_decrypt_pagecache_blocks(struct page *page, unsigned int len,
+				     unsigned int offs)
+{
+	const struct inode *inode = page->mapping->host;
+	const unsigned int blockbits = inode->i_blkbits;
+	const unsigned int blocksize = 1 << blockbits;
+	u64 lblk_num = ((u64)page->index << (PAGE_SHIFT - blockbits)) +
+		       (offs >> blockbits);
+	unsigned int i;
+	int err;
+
+	if (WARN_ON_ONCE(!PageLocked(page)))
+		return -EINVAL;
+
+	if (WARN_ON_ONCE(len <= 0 || !IS_ALIGNED(len | offs, blocksize)))
+		return -EINVAL;
+
+	for (i = offs; i < offs + len; i += blocksize, lblk_num++) {
+		err = fscrypt_crypt_block(inode, FS_DECRYPT, lblk_num, page,
+					  page, blocksize, i, GFP_NOFS);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(fscrypt_decrypt_pagecache_blocks);
+
+/**
+ * fscrypt_decrypt_block_inplace() - Decrypt a filesystem block in-place
+ * @inode:     The inode to which this block belongs
+ * @page:      The page containing the block to decrypt
+ * @len:       Size of block to decrypt.  Doesn't need to be a multiple of the
+ *		fs block size, but must be a multiple of FS_CRYPTO_BLOCK_SIZE.
+ * @offs:      Byte offset within @page at which the block to decrypt begins
+ * @lblk_num:  Filesystem logical block number of the block, i.e. the 0-based
+ *		number of the block within the file
+ *
+ * Decrypt a possibly-compressed filesystem block that is located in an
+ * arbitrary page, not necessarily in the original pagecache page.  The @inode
+ * and @lblk_num must be specified, as they can't be determined from @page.
+ *
+ * Return: 0 on success; -errno on failure
+ */
+int fscrypt_decrypt_block_inplace(const struct inode *inode, struct page *page,
+				  unsigned int len, unsigned int offs,
+				  u64 lblk_num)
+{
+	return fscrypt_crypt_block(inode, FS_DECRYPT, lblk_num, page, page,
+				   len, offs, GFP_NOFS);
+}
+EXPORT_SYMBOL(fscrypt_decrypt_block_inplace);
+
+/*
+ * Validate dentries in encrypted directories to make sure we aren't potentially
+ * caching stale dentries after a key has been added.
+ */
+static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+	struct dentry *dir;
+	int err;
+	int valid;
+
+	/*
+	 * Plaintext names are always valid, since fscrypt doesn't support
+	 * reverting to ciphertext names without evicting the directory's inode
+	 * -- which implies eviction of the dentries in the directory.
+	 */
+	if (!(dentry->d_flags & DCACHE_ENCRYPTED_NAME))
+		return 1;
+
+	/*
+	 * Ciphertext name; valid if the directory's key is still unavailable.
+	 *
+	 * Although fscrypt forbids rename() on ciphertext names, we still must
+	 * use dget_parent() here rather than use ->d_parent directly.  That's
+	 * because a corrupted fs image may contain directory hard links, which
+	 * the VFS handles by moving the directory's dentry tree in the dcache
+	 * each time ->lookup() finds the directory and it already has a dentry
+	 * elsewhere.  Thus ->d_parent can be changing, and we must safely grab
+	 * a reference to some ->d_parent to prevent it from being freed.
+	 */
+
+	if (flags & LOOKUP_RCU)
+		return -ECHILD;
+
+	dir = dget_parent(dentry);
+	err = fscrypt_get_encryption_info(d_inode(dir));
+	valid = !fscrypt_has_encryption_key(d_inode(dir));
+	dput(dir);
+
+	if (err < 0)
+		return err;
+
+	return valid;
+}
+
+const struct dentry_operations fscrypt_d_ops = {
+	.d_revalidate = fscrypt_d_revalidate,
+};
+
+/**
+ * fscrypt_initialize() - allocate major buffers for fs encryption.
+ * @cop_flags:  fscrypt operations flags
+ *
+ * We only call this when we start accessing encrypted files, since it
+ * results in memory getting allocated that wouldn't otherwise be used.
+ *
+ * Return: 0 on success; -errno on failure
+ */
+int fscrypt_initialize(unsigned int cop_flags)
+{
+	int err = 0;
+
+	/* No need to allocate a bounce page pool if this FS won't use it. */
+	if (cop_flags & FS_CFLG_OWN_PAGES)
+		return 0;
+
+	mutex_lock(&fscrypt_init_mutex);
+	if (fscrypt_bounce_page_pool)
+		goto out_unlock;
+
+	err = -ENOMEM;
+	fscrypt_bounce_page_pool =
+		mempool_create_page_pool(num_prealloc_crypto_pages, 0);
+	if (!fscrypt_bounce_page_pool)
+		goto out_unlock;
+
+	err = 0;
+out_unlock:
+	mutex_unlock(&fscrypt_init_mutex);
+	return err;
+}
+
+void fscrypt_msg(const struct inode *inode, const char *level,
+		 const char *fmt, ...)
+{
+	static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
+				      DEFAULT_RATELIMIT_BURST);
+	struct va_format vaf;
+	va_list args;
+
+	if (!__ratelimit(&rs))
+		return;
+
+	va_start(args, fmt);
+	vaf.fmt = fmt;
+	vaf.va = &args;
+	if (inode)
+		printk("%sfscrypt (%s, inode %lu): %pV\n",
+		       level, inode->i_sb->s_id, inode->i_ino, &vaf);
+	else
+		printk("%sfscrypt: %pV\n", level, &vaf);
+	va_end(args);
+}
+
+/**
+ * fscrypt_init() - Set up for fs encryption.
+ */
+static int __init fscrypt_init(void)
+{
+	int err = -ENOMEM;
+
+	/*
+	 * Use an unbound workqueue to allow bios to be decrypted in parallel
+	 * even when they happen to complete on the same CPU.  This sacrifices
+	 * locality, but it's worthwhile since decryption is CPU-intensive.
+	 *
+	 * Also use a high-priority workqueue to prioritize decryption work,
+	 * which blocks reads from completing, over regular application tasks.
+	 */
+	fscrypt_read_workqueue = alloc_workqueue("fscrypt_read_queue",
+						 WQ_UNBOUND | WQ_HIGHPRI,
+						 num_online_cpus());
+	if (!fscrypt_read_workqueue)
+		goto fail;
+
+	fscrypt_info_cachep = KMEM_CACHE(fscrypt_info, SLAB_RECLAIM_ACCOUNT);
+	if (!fscrypt_info_cachep)
+		goto fail_free_queue;
+
+	err = fscrypt_init_keyring();
+	if (err)
+		goto fail_free_info;
+
+	return 0;
+
+fail_free_info:
+	kmem_cache_destroy(fscrypt_info_cachep);
+fail_free_queue:
+	destroy_workqueue(fscrypt_read_workqueue);
+fail:
+	return err;
+}
+late_initcall(fscrypt_init)