CTAP1/U2F accesses attestation material through the store.

This commit is contained in:
Jean-Michel Picod
2020-11-25 17:31:05 +01:00
parent 026b4a66ac
commit 41f7cc7b14

View File

@@ -13,7 +13,6 @@
// limitations under the License. // limitations under the License.
use super::hid::ChannelID; use super::hid::ChannelID;
use super::key_material::{ATTESTATION_CERTIFICATE, ATTESTATION_PRIVATE_KEY};
use super::status_code::Ctap2StatusCode; use super::status_code::Ctap2StatusCode;
use super::CtapState; use super::CtapState;
use alloc::vec::Vec; use alloc::vec::Vec;
@@ -295,14 +294,22 @@ impl Ctap1Command {
return Err(Ctap1StatusCode::SW_VENDOR_KEY_HANDLE_TOO_LONG); return Err(Ctap1StatusCode::SW_VENDOR_KEY_HANDLE_TOO_LONG);
} }
let mut response = let certificate = match ctap_state.persistent_store.attestation_certificate() {
Vec::with_capacity(105 + key_handle.len() + ATTESTATION_CERTIFICATE.len()); Ok(Some(value)) => value,
_ => return Err(Ctap1StatusCode::SW_INS_NOT_SUPPORTED),
};
let private_key = match ctap_state.persistent_store.attestation_private_key() {
Ok(Some(value)) => value,
_ => return Err(Ctap1StatusCode::SW_INS_NOT_SUPPORTED),
};
let mut response = Vec::with_capacity(105 + key_handle.len() + certificate.len());
response.push(Ctap1Command::LEGACY_BYTE); response.push(Ctap1Command::LEGACY_BYTE);
let user_pk = pk.to_uncompressed(); let user_pk = pk.to_uncompressed();
response.extend_from_slice(&user_pk); response.extend_from_slice(&user_pk);
response.push(key_handle.len() as u8); response.push(key_handle.len() as u8);
response.extend(key_handle.clone()); response.extend(key_handle.clone());
response.extend_from_slice(&ATTESTATION_CERTIFICATE); response.extend_from_slice(&certificate);
// The first byte is reserved. // The first byte is reserved.
let mut signature_data = Vec::with_capacity(66 + key_handle.len()); let mut signature_data = Vec::with_capacity(66 + key_handle.len());
@@ -312,7 +319,7 @@ impl Ctap1Command {
signature_data.extend(key_handle); signature_data.extend(key_handle);
signature_data.extend_from_slice(&user_pk); signature_data.extend_from_slice(&user_pk);
let attestation_key = crypto::ecdsa::SecKey::from_bytes(ATTESTATION_PRIVATE_KEY).unwrap(); let attestation_key = crypto::ecdsa::SecKey::from_bytes(private_key).unwrap();
let signature = attestation_key.sign_rfc6979::<crypto::sha256::Sha256>(&signature_data); let signature = attestation_key.sign_rfc6979::<crypto::sha256::Sha256>(&signature_data);
response.extend(signature.to_asn1_der()); response.extend(signature.to_asn1_der());
@@ -373,7 +380,7 @@ impl Ctap1Command {
#[cfg(test)] #[cfg(test)]
mod test { mod test {
use super::super::{CREDENTIAL_ID_BASE_SIZE, USE_SIGNATURE_COUNTER}; use super::super::{key_material, CREDENTIAL_ID_BASE_SIZE, USE_SIGNATURE_COUNTER};
use super::*; use super::*;
use crypto::rng256::ThreadRng256; use crypto::rng256::ThreadRng256;
use crypto::Hash256; use crypto::Hash256;
@@ -434,8 +441,25 @@ mod test {
ctap_state.u2f_up_state.consume_up(START_CLOCK_VALUE); ctap_state.u2f_up_state.consume_up(START_CLOCK_VALUE);
ctap_state.u2f_up_state.grant_up(START_CLOCK_VALUE); ctap_state.u2f_up_state.grant_up(START_CLOCK_VALUE);
let response = let response =
Ctap1Command::process_command(&message, &mut ctap_state, START_CLOCK_VALUE).unwrap(); Ctap1Command::process_command(&message, &mut ctap_state, START_CLOCK_VALUE);
// Certificate and private key are missing
assert_eq!(response, Err(Ctap1StatusCode::SW_INS_NOT_SUPPORTED));
let fake_key = [0x41u8; key_material::ATTESTATION_PRIVATE_KEY_LENGTH];
assert!(ctap_state.persistent_store.set_attestation_private_key(&fake_key).is_ok());
ctap_state.u2f_up_state.consume_up(START_CLOCK_VALUE);
ctap_state.u2f_up_state.grant_up(START_CLOCK_VALUE);
let response =
Ctap1Command::process_command(&message, &mut ctap_state, START_CLOCK_VALUE);
// Certificate is still missing
assert_eq!(response, Err(Ctap1StatusCode::SW_INS_NOT_SUPPORTED));
let fake_cert = [0x99u8; 100]; // Arbitrary length
assert!(ctap_state.persistent_store.set_attestation_certificate(&fake_cert[..]).is_ok());
ctap_state.u2f_up_state.consume_up(START_CLOCK_VALUE);
ctap_state.u2f_up_state.grant_up(START_CLOCK_VALUE);
let response =
Ctap1Command::process_command(&message, &mut ctap_state, START_CLOCK_VALUE).unwrap();
assert_eq!(response[0], Ctap1Command::LEGACY_BYTE); assert_eq!(response[0], Ctap1Command::LEGACY_BYTE);
assert_eq!(response[66], CREDENTIAL_ID_BASE_SIZE as u8); assert_eq!(response[66], CREDENTIAL_ID_BASE_SIZE as u8);
assert!(ctap_state assert!(ctap_state
@@ -447,8 +471,8 @@ mod test {
.is_some()); .is_some());
const CERT_START: usize = 67 + CREDENTIAL_ID_BASE_SIZE; const CERT_START: usize = 67 + CREDENTIAL_ID_BASE_SIZE;
assert_eq!( assert_eq!(
&response[CERT_START..CERT_START + ATTESTATION_CERTIFICATE.len()], &response[CERT_START..CERT_START + fake_cert.len()],
&ATTESTATION_CERTIFICATE[..] &fake_cert[..]
); );
} }