From: Eric Biggers <ebiggers@xxxxxxxxxx>
Add an 'add_enckey' command to xfs_io, to provide a command-line
interface to the FS_IOC_ADD_ENCRYPTION_KEY ioctl.
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
io/encrypt.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++
man/man8/xfs_io.8 | 15 +++++++
2 files changed, 124 insertions(+)
diff --git a/io/encrypt.c b/io/encrypt.c
index 603d569b..056f15bc 100644
--- a/io/encrypt.c
+++ b/io/encrypt.c
@@ -149,6 +149,7 @@ static const struct {
static cmdinfo_t get_encpolicy_cmd;
static cmdinfo_t set_encpolicy_cmd;
+static cmdinfo_t add_enckey_cmd;
static void
get_encpolicy_help(void)
@@ -203,6 +204,22 @@ set_encpolicy_help(void)
"\n"));
}
+static void
+add_enckey_help(void)
+{
+ printf(_(
+"\n"
+" add an encryption key to the filesystem\n"
+"\n"
+" Examples:\n"
+" 'add_enckey' - add key for v2 policies\n"
+" 'add_enckey -d 0000111122223333' - add key for v1 policies w/ given descriptor\n"
+"\n"
+"The key in binary is read from standard input.\n"
+" -d DESCRIPTOR -- master_key_descriptor\n"
+"\n"));
+}
+
static bool
parse_byte_value(const char *arg, __u8 *value_ret)
{
@@ -606,6 +623,88 @@ set_encpolicy_f(int argc, char **argv)
return 0;
}
+static ssize_t
+read_until_limit_or_eof(int fd, void *buf, size_t limit)
+{
+ size_t bytes_read = 0;
+ ssize_t res;
+
+ while (limit) {
+ res = read(fd, buf, limit);
+ if (res < 0)
+ return res;
+ if (res == 0)
+ break;
+ buf += res;
+ bytes_read += res;
+ limit -= res;
+ }
+ return bytes_read;
+}
+
+static int
+add_enckey_f(int argc, char **argv)
+{
+ int c;
+ struct fscrypt_add_key_arg *arg;
+ ssize_t raw_size;
+
+ arg = calloc(1, sizeof(*arg) + FSCRYPT_MAX_KEY_SIZE + 1);
+ if (!arg) {
+ perror("calloc");
+ exitcode = 1;
+ return 0;
+ }
+
+ arg->key_spec.type = FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER;
+
+ while ((c = getopt(argc, argv, "d:")) != EOF) {
+ switch (c) {
+ case 'd':
+ arg->key_spec.type = FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR;
+ if (!str2keydesc(optarg, arg->key_spec.u.descriptor))
+ goto out;
+ break;
+ default:
+ return command_usage(&add_enckey_cmd);
+ }
+ }
+ argc -= optind;
+ argv += optind;
+
+ if (argc != 0)
+ return command_usage(&add_enckey_cmd);
+
+ raw_size = read_until_limit_or_eof(STDIN_FILENO, arg->raw,
+ FSCRYPT_MAX_KEY_SIZE + 1);
+ if (raw_size < 0) {
+ fprintf(stderr, _("Error reading key from stdin: %s\n"),
+ strerror(errno));
+ exitcode = 1;
+ goto out;
+ }
+ if (raw_size > FSCRYPT_MAX_KEY_SIZE) {
+ fprintf(stderr,
+ _("Invalid key; got > FSCRYPT_MAX_KEY_SIZE (%d) bytes on stdin!\n"),
+ FSCRYPT_MAX_KEY_SIZE);
+ goto out;
+ }
+ arg->raw_size = raw_size;
+
+ if (ioctl(file->fd, FS_IOC_ADD_ENCRYPTION_KEY, arg) != 0) {
+ fprintf(stderr, _("Error adding encryption key: %s\n"),
+ strerror(errno));
+ exitcode = 1;
+ goto out;
+ }
+ printf(_("Added encryption key with %s %s\n"),
+ keyspectype(&arg->key_spec), keyspec2str(&arg->key_spec));
+out:
+ memset(arg->raw, 0, FSCRYPT_MAX_KEY_SIZE + 1);
+ free(arg);
+ return 0;
+}
+
void
encrypt_init(void)
{
@@ -630,6 +729,16 @@ encrypt_init(void)
_("assign an encryption policy to the current file");
set_encpolicy_cmd.help = set_encpolicy_help;
+ add_enckey_cmd.name = "add_enckey";
+ add_enckey_cmd.cfunc = add_enckey_f;
+ add_enckey_cmd.args = _("[-d descriptor]");
+ add_enckey_cmd.argmin = 0;
+ add_enckey_cmd.argmax = -1;
+ add_enckey_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK;
+ add_enckey_cmd.oneline = _("add an encryption key to the filesystem");
+ add_enckey_cmd.help = add_enckey_help;
+
add_command(&get_encpolicy_cmd);
add_command(&set_encpolicy_cmd);
+ add_command(&add_enckey_cmd);
}
diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
index 18fcde0f..7d6a23fe 100644
--- a/man/man8/xfs_io.8
+++ b/man/man8/xfs_io.8
@@ -749,6 +749,21 @@ Test whether v2 encryption policies are supported. Prints "supported",
.RE
.PD
.TP
+.BI "add_enckey [ \-d " descriptor " ]"
+On filesystems that support encryption, add an encryption key to the filesystem
+containing the currently open file. The key in binary (typically 64 bytes long)
+is read from standard input.
+.RS 1.0i
+.PD 0
+.TP 0.4i
+.BI \-d " descriptor"
+key descriptor, as a 16-character hex string (8 bytes). If given, the key will
+be available for use by v1 encryption policies that use this descriptor.
+Otherwise, the key is added as a v2 policy key, and on success the resulting
+"key identifier" will be printed.
+.RE
+.PD
+.TP
.BR lsattr " [ " \-R " | " \-D " | " \-a " | " \-v " ]"
List extended inode flags on the currently open file. If the
.B \-R
--
2.23.0.444.g18eeb5a265-goog
