diff options
Diffstat (limited to 'Documentation/security/keys.txt')
| -rw-r--r-- | Documentation/security/keys.txt | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt index 5fe04a7cc03d..5f554aab8751 100644 --- a/Documentation/security/keys.txt +++ b/Documentation/security/keys.txt @@ -857,6 +857,31 @@ The keyctl syscall functions are: supported, error ENOKEY if the key could not be found, or error EACCES if the key is not readable by the caller. + (*) Restrict keyring linkage + + long keyctl(KEYCTL_RESTRICT_KEYRING, key_serial_t keyring, + const char *type, const char *restriction); + + An existing keyring can restrict linkage of additional keys by evaluating + the contents of the key according to a restriction scheme. + + "keyring" is the key ID for an existing keyring to apply a restriction + to. It may be empty or may already have keys linked. Existing linked keys + will remain in the keyring even if the new restriction would reject them. + + "type" is a registered key type. + + "restriction" is a string describing how key linkage is to be restricted. + The format varies depending on the key type, and the string is passed to + the lookup_restriction() function for the requested type. It may specify + a method and relevant data for the restriction such as signature + verification or constraints on key payload. If the requested key type is + later unregistered, no keys may be added to the keyring after the key type + is removed. + + To apply a keyring restriction the process must have Set Attribute + permission and the keyring must not be previously restricted. + =============== KERNEL SERVICES =============== |