1 files changed, 6 insertions, 286 deletions

diff --git a/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c b/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c
index 707758a..1710e25 100644
--- a/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c
+++ b/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c
@@ -36,6 +36,7 @@
 #endif
 
 #include "crypto.h"
+#include "fscrypt.h"
 
 /* Size (prime number) of hash table for link counting */
 #define HASH_TABLE_SIZE 10099
@@ -110,66 +111,6 @@ struct inum_mapping {
 	struct stat st;
 };
 
-#ifndef FS_KEY_DESCRIPTOR_SIZE
-#define FS_KEY_DESCRIPTOR_SIZE  8
-#endif
-#define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
-#define FS_KEY_DERIVATION_NONCE_SIZE	16
-
-#ifndef FS_ENCRYPTION_MODE_AES_128_CBC
-#define FS_ENCRYPTION_MODE_AES_128_CBC 5
-#endif
-
-#ifndef FS_ENCRYPTION_MODE_AES_128_CTS
-#define FS_ENCRYPTION_MODE_AES_128_CTS 6
-#endif
-
-#ifndef FS_POLICY_FLAGS_VALID
-#define FS_POLICY_FLAGS_PAD_4		0x00
-#define FS_POLICY_FLAGS_PAD_8		0x01
-#define FS_POLICY_FLAGS_PAD_16		0x02
-#define FS_POLICY_FLAGS_PAD_32		0x03
-#define FS_POLICY_FLAGS_PAD_MASK	0x03
-#define FS_POLICY_FLAGS_VALID		0x03
-#endif
-
-#define FS_CRYPTO_BLOCK_SIZE	16
-
-/**
- * Encryption context for inode
- *
- * Protector format:
- *  1 byte: Protector format (1 = this version)
- *  1 byte: File contents encryption mode
- *  1 byte: File names encryption mode
- *  1 byte: Flags
- *  8 bytes: Master Key descriptor
- *  16 bytes: Encryption Key derivation nonce
- */
-struct fscrypt_context {
-	__u8 format;
-	__u8 contents_encryption_mode;
-	__u8 filenames_encryption_mode;
-	__u8 flags;
-	__u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
-	__u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
-} __attribute__((packed));
-
-/**
- * For encrypted symlinks, the ciphertext length is stored at the beginning
- * of the string in little-endian format.
- */
-struct fscrypt_symlink_data {
-	__le16 len;
-	char encrypted_path[1];
-} __attribute__((packed));
-
-
-#ifndef FS_MAX_KEY_SIZE
-#define FS_MAX_KEY_SIZE	64
-#endif
-static __u8 fscrypt_masterkey[FS_MAX_KEY_SIZE];
-
 /*
  * Because we copy functions from the kernel, we use a subset of the UBIFS
  * file-system description object struct ubifs_info.
@@ -186,7 +127,6 @@ int yes;
 static char *root;
 static int root_len;
 static struct fscrypt_context *root_fctx;
-static struct cipher *fscrypt_cipher;
 static struct stat root_st;
 static char *output;
 static int out_fd;
@@ -541,160 +481,6 @@ static long long get_bytes(const char *str)
 
 	return bytes;
 }
-
-static unsigned char *calc_fscrypt_subkey(struct fscrypt_context *fctx)
-{
-	int ret;
-	unsigned char *new_key = xmalloc(FS_MAX_KEY_SIZE);
-
-	ret = derive_key_aes(fctx->nonce, fscrypt_masterkey, FS_MAX_KEY_SIZE, new_key);
-	if (ret < 0) {
-		err_msg("derive_key_aes failed: %i\n", ret);
-
-		free(new_key);
-		new_key = NULL;
-	}
-
-	return new_key;
-}
-
-static struct fscrypt_context *inherit_fscrypt_context(struct fscrypt_context *fctx)
-{
-	struct fscrypt_context *new_fctx = NULL;
-
-	if (fctx) {
-		new_fctx = xmalloc(sizeof(*new_fctx));
-		new_fctx->format = fctx->format;
-		new_fctx->contents_encryption_mode = fctx->contents_encryption_mode;
-		new_fctx->filenames_encryption_mode = fctx->filenames_encryption_mode;
-		new_fctx->flags = fctx->flags;
-		memcpy(new_fctx->master_key_descriptor, fctx->master_key_descriptor,
-		       FS_KEY_DESCRIPTOR_SIZE);
-		RAND_bytes((void *)&new_fctx->nonce, FS_KEY_DERIVATION_NONCE_SIZE);
-	}
-
-	return new_fctx;
-}
-
-static void free_fscrypt_context(struct fscrypt_context *fctx)
-{
-	free(fctx);
-}
-
-static void print_fscrypt_master_key_descriptor(struct fscrypt_context *fctx)
-{
-	int i;
-
-	normsg_cont("fscrypt master key descriptor: ");
-	for (i = 0; i < FS_KEY_DESCRIPTOR_SIZE; i++) {
-		normsg_cont("%02x", fctx->master_key_descriptor[i]);
-	}
-	normsg("");
-}
-
-static int xdigit(int x)
-{
-	if (isupper(x))
-		return x - 'A' + 0x0A;
-	if (islower(x))
-		return x - 'a' + 0x0A;
-	return x - '0';
-}
-
-static int parse_key_descriptor(const char *desc, __u8 *dst)
-{
-	int i, hi, lo;
-
-	for (i = 0; i < FS_KEY_DESCRIPTOR_SIZE; ++i) {
-		if (!desc[i * 2] || !desc[i * 2 + 1]) {
-			err_msg("key descriptor '%s' is too short", desc);
-			return -1;
-		}
-		if (!isxdigit(desc[i * 2]) || !isxdigit(desc[i * 2 + 1])) {
-			err_msg("invalid key descriptor '%s'", desc);
-			return -1;
-		}
-
-		hi = xdigit(desc[i * 2]);
-		lo = xdigit(desc[i * 2 + 1]);
-
-		dst[i] = (hi << 4) | lo;
-	}
-
-	if (desc[i * 2]) {
-		err_msg("key descriptor '%s' is too long", desc);
-		return -1;
-	}
-	return 0;
-}
-
-static int load_master_key(const char *key_file)
-{
-	int kf;
-	ssize_t keysize;
-
-	kf = open(key_file, O_RDONLY);
-	if (kf < 0) {
-		sys_errmsg("open '%s'", key_file);
-		return -1;
-	}
-
-	keysize = read(kf, fscrypt_masterkey, sizeof(fscrypt_masterkey));
-	if (keysize < 0) {
-		sys_errmsg("read '%s'", key_file);
-		goto fail;
-	}
-	if (keysize == 0) {
-		err_msg("loading key from '%s': file is empty", key_file);
-		goto fail;
-	}
-
-	close(kf);
-	return 0;
-fail:
-	close(kf);
-	return -1;
-}
-
-static struct fscrypt_context *init_fscrypt_context(unsigned int flags,
-						const char *key_file,
-						const char *key_descriptor)
-{
-	__u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
-	__u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
-	struct fscrypt_context *new_fctx;
-
-	if (parse_key_descriptor(key_descriptor, master_key_descriptor))
-		return NULL;
-
-	if (load_master_key(key_file))
-		return NULL;
-
-	RAND_bytes((void *)nonce, FS_KEY_DERIVATION_NONCE_SIZE);
-
-	new_fctx = xmalloc(sizeof(*new_fctx));
-
-	new_fctx->format = FS_ENCRYPTION_CONTEXT_FORMAT_V1;
-	new_fctx->contents_encryption_mode = FS_ENCRYPTION_MODE_AES_128_CBC;
-	new_fctx->filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_128_CTS;
-	new_fctx->flags = flags;
-
-	memcpy(&new_fctx->nonce, nonce, FS_KEY_DERIVATION_NONCE_SIZE);
-	memcpy(&new_fctx->master_key_descriptor, master_key_descriptor,
-		FS_KEY_DESCRIPTOR_SIZE);
-	return new_fctx;
-}
-
-unsigned int fscrypt_fname_encrypted_size(struct fscrypt_context *fctx, unsigned int ilen)
-{
-	int padding;
-
-	padding = 4 << (fctx->flags & FS_POLICY_FLAGS_PAD_MASK);
-	ilen = max_t(unsigned int, ilen, FS_CRYPTO_BLOCK_SIZE);
-	return round_up(ilen, padding);
-}
-
-
 /**
  * open_ubi - open the UBI volume.
  * @node: name of the UBI volume character device to fetch information about
@@ -972,19 +758,11 @@ static int get_options(int argc, char**argv)
 		c->double_hash = 1;
 		c->encrypted = 1;
 
-		root_fctx = init_fscrypt_context(fscrypt_flags,
+		root_fctx = init_fscrypt_context(cipher_name, fscrypt_flags,
 						key_file, key_desc);
 		if (!root_fctx)
 			return -1;
 
-		fscrypt_cipher = get_cipher(cipher_name);
-		if (!fscrypt_cipher) {
-			fprintf(stderr, "Cannot find cipher '%s'\n"
-				"Try `%s --help' for more information\n",
-				cipher_name, PROGRAM_NAME);
-			return -1;
-		}
-
 		print_fscrypt_master_key_descriptor(root_fctx);
 	}
 
@@ -1616,39 +1394,6 @@ static int set_fscrypt_context(struct ubifs_ino_node *host_ino, ino_t inum,
 			 fctx, sizeof(*fctx));
 }
 
-static int encrypt_path(void **outbuf, void *data, unsigned int data_len,
-			unsigned int max_namelen, struct fscrypt_context *fctx)
-{
-	void *inbuf, *crypt_key;
-	unsigned int padding = 4 << (fctx->flags & FS_POLICY_FLAGS_PAD_MASK);
-	unsigned int cryptlen;
-	int ret;
-
-	cryptlen = max_t(unsigned int, data_len, FS_CRYPTO_BLOCK_SIZE);
-	cryptlen = round_up(cryptlen, padding);
-	cryptlen = min(cryptlen, max_namelen);
-
-	inbuf = xmalloc(cryptlen);
-	/* CTS mode needs a block size aligned buffer */
-	*outbuf = xmalloc(round_up(cryptlen, FS_CRYPTO_BLOCK_SIZE));
-
-	memset(inbuf, 0, cryptlen);
-	memcpy(inbuf, data, data_len);
-
-	crypt_key = calc_fscrypt_subkey(fctx);
-	if (!crypt_key)
-		return err_msg("could not compute subkey");
-
-	ret = fscrypt_cipher->encrypt_fname(inbuf, cryptlen,
-					    crypt_key, *outbuf);
-	if (ret < 0)
-		return err_msg("could not encrypt filename");
-
-	free(crypt_key);
-	free(inbuf);
-	return cryptlen;
-}
-
 static int encrypt_symlink(void *dst, void *data, unsigned int data_len,
 			   struct fscrypt_context *fctx)
 {
@@ -2011,35 +1756,10 @@ static int add_file(const char *path_name, struct stat *st, ino_t inum,
 		if (!fctx) {
 			dn->compr_size = 0;
 		} else {
-			void *inbuf, *outbuf, *crypt_key;
-			size_t ret, pad_len = round_up(out_len, FS_CRYPTO_BLOCK_SIZE);
-
-			dn->compr_size = out_len;
-
-			inbuf = xzalloc(pad_len);
-			outbuf = xzalloc(pad_len);
-
-			memcpy(inbuf, &dn->data, out_len);
-
-			crypt_key = calc_fscrypt_subkey(fctx);
-			if (!crypt_key)
-				return err_msg("could not compute subkey");
-
-			ret = fscrypt_cipher->encrypt_block(inbuf, pad_len,
-							    crypt_key, block_no,
-							    outbuf);
-			if (ret != pad_len) {
-				return err_msg("encrypt_block returned %zi "
-						"instead of %zi", ret, pad_len);
-			}
-
-			memcpy(&dn->data, outbuf, pad_len);
-
-			out_len = pad_len;
-
-			free(inbuf);
-			free(outbuf);
-			free(crypt_key);
+			ret = encrypt_data_node(fctx, block_no, dn, out_len);
+			if (ret < 0)
+				return ret;
+			out_len = ret;
 		}
 
 		dn_len = UBIFS_DATA_NODE_SZ + out_len;