From: Eric Biggers <[email protected]> Currently fscrypt-crypt-util assumes that the number of the first block encrypted/decrypted is 0. I.e., it replicates either contents encryption from the start of a file, or encryption of a filename.
However, to easily test compression+encryption on f2fs, we need the ability to specify a different starting block number. Add a --block-number option which does this. Signed-off-by: Eric Biggers <[email protected]> --- src/fscrypt-crypt-util.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/src/fscrypt-crypt-util.c b/src/fscrypt-crypt-util.c index 5c065116..26698d7a 100644 --- a/src/fscrypt-crypt-util.c +++ b/src/fscrypt-crypt-util.c @@ -59,6 +59,8 @@ static void usage(FILE *fp) "WARNING: this program is only meant for testing, not for \"real\" use!\n" "\n" "Options:\n" +" --block-number=BNUM Starting block number for IV generation.\n" +" Default: 0\n" " --block-size=BLOCK_SIZE Encrypt each BLOCK_SIZE bytes independently.\n" " Default: 4096 bytes\n" " --decrypt Decrypt instead of encrypt\n" @@ -1787,6 +1789,7 @@ struct key_and_iv_params { bool file_nonce_specified; bool iv_ino_lblk_64; bool iv_ino_lblk_32; + u64 block_number; u64 inode_number; u8 fs_uuid[UUID_SIZE]; bool fs_uuid_specified; @@ -1839,6 +1842,9 @@ static void get_key_and_iv(const struct key_and_iv_params *params, memset(iv, 0, sizeof(*iv)); + /* Overridden later for iv_ino_lblk_{64,32} */ + iv->block_number = cpu_to_le64(params->block_number); + if (params->iv_ino_lblk_64 || params->iv_ino_lblk_32) { const char *opt = params->iv_ino_lblk_64 ? "--iv-ino-lblk-64" : "--iv-ino-lblk-32"; @@ -1852,6 +1858,8 @@ static void get_key_and_iv(const struct key_and_iv_params *params, die("%s requires --inode-number", opt); if (params->mode_num == 0) die("%s requires --mode-num", opt); + if (params->block_number > UINT32_MAX) + die("%s can't use --block-number > UINT32_MAX", opt); if (params->inode_number > UINT32_MAX) die("%s can't use --inode-number > UINT32_MAX", opt); } @@ -1881,6 +1889,7 @@ static void get_key_and_iv(const struct key_and_iv_params *params, info[infolen++] = params->mode_num; memcpy(&info[infolen], params->fs_uuid, UUID_SIZE); infolen += UUID_SIZE; + iv->block_number32 = cpu_to_le32(params->block_number); iv->inode_number = cpu_to_le32(params->inode_number); } else if (params->iv_ino_lblk_32) { info[infolen++] = HKDF_CONTEXT_IV_INO_LBLK_32_KEY; @@ -1888,7 +1897,9 @@ static void get_key_and_iv(const struct key_and_iv_params *params, memcpy(&info[infolen], params->fs_uuid, UUID_SIZE); infolen += UUID_SIZE; iv->block_number32 = - cpu_to_le32(hash_inode_number(params)); + cpu_to_le32(hash_inode_number(params) + + params->block_number); + iv->inode_number = 0; } else if (params->mode_num != 0) { info[infolen++] = HKDF_CONTEXT_DIRECT_KEY; info[infolen++] = params->mode_num; @@ -1913,6 +1924,7 @@ static void get_key_and_iv(const struct key_and_iv_params *params, } enum { + OPT_BLOCK_NUMBER, OPT_BLOCK_SIZE, OPT_DECRYPT, OPT_FILE_NONCE, @@ -1927,6 +1939,7 @@ enum { }; static const struct option longopts[] = { + { "block-number", required_argument, NULL, OPT_BLOCK_NUMBER }, { "block-size", required_argument, NULL, OPT_BLOCK_SIZE }, { "decrypt", no_argument, NULL, OPT_DECRYPT }, { "file-nonce", required_argument, NULL, OPT_FILE_NONCE }, @@ -1968,6 +1981,12 @@ int main(int argc, char *argv[]) while ((c = getopt_long(argc, argv, "", longopts, NULL)) != -1) { switch (c) { + case OPT_BLOCK_NUMBER: + errno = 0; + params.block_number = strtoull(optarg, &tmp, 10); + if (*tmp || errno) + die("Invalid block number: %s", optarg); + break; case OPT_BLOCK_SIZE: errno = 0; block_size = strtoul(optarg, &tmp, 10); -- 2.28.0 _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
