diff --git a/man/crypttab.xml b/man/crypttab.xml
index 90d8ce95f..5f386e55f 100644
--- a/man/crypttab.xml
+++ b/man/crypttab.xml
@@ -163,6 +163,20 @@
given by the key size.
+
+ key-slot=
+
+ Specifies the key slot to
+ compare the passphrase or key against.
+ If the key slot does not match the given
+ passphrase or key, but another would, the
+ setup of the device will fail regardless.
+ This implies luks. See
+ cryptsetup8
+ for possible values. The default is to try
+ all key slots in sequential order.
+
+
luks
diff --git a/src/cryptsetup/cryptsetup.c b/src/cryptsetup/cryptsetup.c
index 0a15b503b..033c0cdb7 100644
--- a/src/cryptsetup/cryptsetup.c
+++ b/src/cryptsetup/cryptsetup.c
@@ -39,6 +39,7 @@
static const char *opt_type = NULL; /* CRYPT_LUKS1, CRYPT_TCRYPT or CRYPT_PLAIN */
static char *opt_cipher = NULL;
static unsigned opt_key_size = 0;
+static int opt_key_slot = CRYPT_ANY_SLOT;
static unsigned opt_keyfile_size = 0;
static unsigned opt_keyfile_offset = 0;
static char *opt_hash = NULL;
@@ -87,6 +88,14 @@ static int parse_one_option(const char *option) {
return 0;
}
+ } else if (startswith(option, "key-slot=")) {
+
+ opt_type = CRYPT_LUKS1;
+ if (safe_atoi(option+9, &opt_key_slot) < 0) {
+ log_error("key-slot= parse failure, ignoring.");
+ return 0;
+ }
+
} else if (startswith(option, "tcrypt-keyfile=")) {
opt_type = CRYPT_TCRYPT;
@@ -425,7 +434,7 @@ static int attach_luks_or_plain(struct crypt_device *cd,
crypt_get_device_name(cd));
if (key_file) {
- r = crypt_activate_by_keyfile_offset(cd, name, CRYPT_ANY_SLOT,
+ r = crypt_activate_by_keyfile_offset(cd, name, opt_key_slot,
key_file, opt_keyfile_size,
opt_keyfile_offset, flags);
if (r < 0) {
@@ -439,7 +448,7 @@ static int attach_luks_or_plain(struct crypt_device *cd,
if (pass_volume_key)
r = crypt_activate_by_volume_key(cd, name, *p, opt_key_size, flags);
else
- r = crypt_activate_by_passphrase(cd, name, CRYPT_ANY_SLOT, *p, strlen(*p), flags);
+ r = crypt_activate_by_passphrase(cd, name, opt_key_slot, *p, strlen(*p), flags);
if (r >= 0)
break;