From 2144f88af24e03879b4c09fe15c5c982d296b7a3 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Thu, 18 Oct 2018 16:36:53 +0200 Subject: mkfs.ubifs: Move symlink data encryption to helper function Signed-off-by: David Oberhollenzer Signed-off-by: Richard Weinberger --- ubifs-utils/mkfs.ubifs/mkfs.ubifs.c | 81 ++++++++++++++++++++----------------- 1 file changed, 44 insertions(+), 37 deletions(-) diff --git a/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c b/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c index b7d68c6..b402945 100644 --- a/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c +++ b/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c @@ -1443,6 +1443,46 @@ static int set_fscrypt_context(struct ubifs_ino_node *host_ino, ino_t inum, fctx, sizeof(*fctx)); } +static int encrypt_symlink(void *dst, void *data, unsigned int data_len, + struct fscrypt_context *fctx) +{ + struct fscrypt_symlink_data *sd; + void *inbuf, *outbuf, *crypt_key; + unsigned int max_namelen = UBIFS_MAX_INO_DATA; + unsigned int padding = 4 << (fctx->flags & FS_POLICY_FLAGS_PAD_MASK); + unsigned int cryptlen; + unsigned int link_disk_len = fscrypt_fname_encrypted_size(fctx, data_len) + sizeof(struct fscrypt_symlink_data); + + cryptlen = max_t(unsigned int, data_len, FS_CRYPTO_BLOCK_SIZE); + cryptlen = round_up(cryptlen, padding); + cryptlen = min(cryptlen, max_namelen); + + sd = xzalloc(link_disk_len); + 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"); + if (encrypt_aes128_cbc_cts(inbuf, cryptlen, crypt_key, outbuf) < 0) + return err_msg("could not encrypt filename"); + + memcpy(sd->encrypted_path, outbuf, cryptlen); + sd->len = cpu_to_le16(cryptlen); + memcpy(dst, sd, link_disk_len); + ((char *)dst)[link_disk_len - 1] = '\0'; + + free(crypt_key); + free(inbuf); + free(outbuf); + free(sd); + return link_disk_len; +} + /** * add_inode - write an inode. * @st: stat information of source inode @@ -1503,43 +1543,10 @@ static int add_inode(struct stat *st, ino_t inum, void *data, if (!fctx) { memcpy(&ino->data, data, data_len); } else { - //TODO turn this into a common helper - struct fscrypt_symlink_data *sd; - void *inbuf, *outbuf, *crypt_key; - unsigned int max_namelen = UBIFS_MAX_INO_DATA; - unsigned int padding = 4 << (fctx->flags & FS_POLICY_FLAGS_PAD_MASK); - unsigned int cryptlen; - unsigned int link_disk_len = fscrypt_fname_encrypted_size(fctx, data_len) + sizeof(struct fscrypt_symlink_data); - - cryptlen = max_t(unsigned int, data_len, FS_CRYPTO_BLOCK_SIZE); - cryptlen = round_up(cryptlen, padding); - cryptlen = min(cryptlen, max_namelen); - - sd = xzalloc(link_disk_len); - 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"); - if (encrypt_aes128_cbc_cts(inbuf, cryptlen, crypt_key, outbuf) < 0) - return err_msg("could not encrypt filename"); - - memcpy(sd->encrypted_path, outbuf, cryptlen); - sd->len = cpu_to_le16(cryptlen); - memcpy(&ino->data, sd, link_disk_len); - ((char *)&ino->data)[link_disk_len - 1] = '\0'; - - data_len = link_disk_len; - - free(crypt_key); - free(inbuf); - free(outbuf); - free(sd); + ret = encrypt_symlink(&ino->data, data, data_len, fctx); + if (ret < 0) + return ret; + data_len = ret; } } ino->data_len = cpu_to_le32(data_len); -- cgit v1.2.3