v/tpm2-store
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity
tpm2-store/src/main.rs
Patrick Uiterwijk a2650d5234 Initial commit
2020-07-16 16:22:34 +02:00

1338 lines
44 KiB
Rust
Raw Blame History

// Copyright 2020 Patrick Uiterwijk
//
// Licensed under the EUPL-1.2-or-later
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://joinup.ec.europa.eu/collection/eupl/eupl-text-eupl-12
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
use std::convert::{TryFrom, TryInto};
use std::error::Error;
use std::fmt;
use std::fs;
extern crate base64;
extern crate biscuit;
extern crate serde;
extern crate serde_json;
extern crate tss_esapi;
use std::env;
use std::io::{self, Read, Write};
use biscuit::jwe;
use biscuit::CompactJson;
use tss_esapi::constants;
use tss_esapi::tss2_esys::{ESYS_TR, ESYS_TR_NONE, ESYS_TR_RH_OWNER};
use tss_esapi::utils;
use tss_esapi::utils::tcti;
use tss_esapi::Context;
use serde::{Deserialize, Serialize};
pub fn serialize_as_base64_url_no_pad<S>(bytes: &[u8], serializer: S) -> Result<S::Ok, S::Error>
where
S: serde::Serializer,
{
serializer.serialize_str(&base64::encode_config(bytes, base64::URL_SAFE_NO_PAD))
}
pub fn deserialize_as_base64_url_no_pad<'de, D>(deserializer: D) -> Result<Vec<u8>, D::Error>
where
D: serde::Deserializer<'de>,
{
String::deserialize(deserializer).and_then(|string| {
base64::decode_config(&string, base64::URL_SAFE_NO_PAD).map_err(serde::de::Error::custom)
})
}
pub fn serialize_as_base64<S>(bytes: &[u8], serializer: S) -> Result<S::Ok, S::Error>
where
S: serde::Serializer,
{
serializer.serialize_str(&base64::encode(bytes))
}
pub fn deserialize_as_base64<'de, D>(deserializer: D) -> Result<Vec<u8>, D::Error>
where
D: serde::Deserializer<'de>,
{
String::deserialize(deserializer)
.and_then(|string| base64::decode(&string).map_err(serde::de::Error::custom))
}
#[derive(Debug)]
enum PinError {
Text(&'static str),
NoCommand,
Serde(serde_json::Error),
IO(std::io::Error),
TPM(tss_esapi::response_code::Error),
JWE(biscuit::errors::Error),
Base64Decoding(base64::DecodeError),
Utf8(std::str::Utf8Error),
}
impl PinError {}
impl fmt::Display for PinError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
PinError::Text(e) => write!(f, "Error: {}", e),
PinError::Serde(err) => {
write!(f, "Serde error: ")?;
err.fmt(f)
}
PinError::IO(err) => {
write!(f, "IO error: ")?;
err.fmt(f)
}
PinError::TPM(err) => {
write!(f, "TPM error: ")?;
err.fmt(f)
}
PinError::JWE(err) => {
write!(f, "JWE error: ")?;
err.fmt(f)
}
PinError::Base64Decoding(err) => {
write!(f, "Base64 Decoding error: ")?;
err.fmt(f)
}
PinError::Utf8(err) => {
write!(f, "UTF8 error: ")?;
err.fmt(f)
}
PinError::NoCommand => write!(f, "No command provided"),
}
}
}
impl Error for PinError {}
impl From<&'static str> for PinError {
fn from(err: &'static str) -> Self {
PinError::Text(err)
}
}
impl From<serde_json::Error> for PinError {
fn from(err: serde_json::Error) -> Self {
PinError::Serde(err)
}
}
impl From<std::io::Error> for PinError {
fn from(err: std::io::Error) -> Self {
PinError::IO(err)
}
}
impl From<tss_esapi::response_code::Error> for PinError {
fn from(err: tss_esapi::response_code::Error) -> Self {
PinError::TPM(err)
}
}
impl From<biscuit::errors::Error> for PinError {
fn from(err: biscuit::errors::Error) -> Self {
PinError::JWE(err)
}
}
impl From<base64::DecodeError> for PinError {
fn from(err: base64::DecodeError) -> Self {
PinError::Base64Decoding(err)
}
}
impl From<std::str::Utf8Error> for PinError {
fn from(err: std::str::Utf8Error) -> Self {
PinError::Utf8(err)
}
}
#[derive(Debug)]
enum TPMPolicyStep {
NoStep,
PCRs(
tss_esapi::utils::algorithm_specifiers::HashingAlgorithm,
Vec<u64>,
Box<TPMPolicyStep>,
),
Authorized {
signkey: PublicKey,
policy_ref: Vec<u8>,
policies: Option<SignedPolicyList>,
next: Box<TPMPolicyStep>,
},
Or([Box<TPMPolicyStep>; 8]),
}
fn create_and_set_tpm2_session(
ctx: &mut tss_esapi::Context,
session_type: tss_esapi::tss2_esys::TPM2_SE,
) -> Result<ESYS_TR, PinError> {
let session = ctx.start_auth_session(
ESYS_TR_NONE,
ESYS_TR_NONE,
&[],
session_type,
utils::TpmtSymDefBuilder::aes_256_cfb(),
tss_esapi::constants::TPM2_ALG_SHA256,
)?;
let session_attr = utils::TpmaSessionBuilder::new()
.with_flag(tss_esapi::constants::TPMA_SESSION_DECRYPT)
.with_flag(tss_esapi::constants::TPMA_SESSION_ENCRYPT)
.build();
ctx.tr_sess_set_attributes(session, session_attr)?;
ctx.set_sessions((session, ESYS_TR_NONE, ESYS_TR_NONE));
Ok(session)
}
impl TPMPolicyStep {
/// Sends the generate policy to the TPM2, and sets the authorized policy as active
/// Returns the policy_digest for authInfo
fn send_policy(
self,
ctx: &mut tss_esapi::Context,
trial_policy: bool,
) -> Result<Option<tss_esapi::utils::Digest>, PinError> {
let pol_type = if trial_policy {
tss_esapi::constants::TPM2_SE_TRIAL
} else {
tss_esapi::constants::TPM2_SE_POLICY
};
let session = ctx.start_auth_session(
ESYS_TR_NONE,
ESYS_TR_NONE,
&[],
pol_type,
utils::TpmtSymDefBuilder::aes_256_cfb(),
tss_esapi::constants::TPM2_ALG_SHA256,
)?;
let session_attr = utils::TpmaSessionBuilder::new()
.with_flag(tss_esapi::constants::TPMA_SESSION_DECRYPT)
.with_flag(tss_esapi::constants::TPMA_SESSION_ENCRYPT)
.build();
ctx.tr_sess_set_attributes(session, session_attr)?;
match self {
TPMPolicyStep::NoStep => {
create_and_set_tpm2_session(ctx, tss_esapi::constants::TPM2_SE_HMAC)?;
Ok(None)
}
_ => {
self._send_policy(ctx, session)?;
let pol_digest = ctx.policy_get_digest(session)?;
if trial_policy {
create_and_set_tpm2_session(ctx, tss_esapi::constants::TPM2_SE_HMAC)?;
} else {
ctx.set_sessions((session, ESYS_TR_NONE, ESYS_TR_NONE));
}
Ok(Some(pol_digest))
}
}
}
fn _send_policy(
self,
ctx: &mut tss_esapi::Context,
policy_session: tss_esapi::tss2_esys::ESYS_TR,
) -> Result<(), PinError> {
match self {
TPMPolicyStep::NoStep => Ok(()),
TPMPolicyStep::PCRs(pcr_hash_alg, pcr_ids, next) => {
let pcr_ids: Result<Vec<tss_esapi::utils::PcrSlot>, PinError> =
pcr_ids.iter().map(|x| pcr_id_to_slot(x)).collect();
let pcr_ids: Vec<tss_esapi::utils::PcrSlot> = pcr_ids?;
let pcr_sel = tss_esapi::utils::PcrSelectionsBuilder::new()
.with_selection(pcr_hash_alg, &pcr_ids)
.build();
// Ensure PCR reading occurs with no sessions (we don't use audit sessions)
let old_ses = ctx.sessions();
ctx.set_sessions((ESYS_TR_NONE, ESYS_TR_NONE, ESYS_TR_NONE));
let (_update_counter, pcr_sel, pcr_data) = ctx.pcr_read(pcr_sel)?;
ctx.set_sessions(old_ses);
let concatenated_pcr_values: Vec<&[u8]> = pcr_ids
.iter()
.map(|x| {
pcr_data
.pcr_bank(pcr_hash_alg)
.unwrap()
.pcr_value(*x)
.unwrap()
.value()
})
.collect();
let concatenated_pcr_values = concatenated_pcr_values.as_slice().concat();
let (hashed_data, _ticket) = ctx.hash(
&concatenated_pcr_values,
tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha256,
tss_esapi::utils::Hierarchy::Owner,
)?;
ctx.policy_pcr(policy_session, &hashed_data, pcr_sel)?;
next._send_policy(ctx, policy_session)
}
TPMPolicyStep::Authorized {
signkey,
policy_ref,
policies,
next,
} => {
let policy_ref = tss_esapi::utils::Digest::try_from(policy_ref)?;
let tpm_signkey = tss_esapi::tss2_esys::TPM2B_PUBLIC::try_from(&signkey)?;
let loaded_key =
ctx.load_external_public(&tpm_signkey, tss_esapi::utils::Hierarchy::Owner)?;
let loaded_key_name = ctx.tr_get_name(loaded_key)?;
let (approved_policy, check_ticket) = match policies {
None => {
/* Some TPMs don't seem to like the Null ticket.. Let's just use a dummy
let null_ticket = tss_esapi::tss2_esys::TPMT_TK_VERIFIED {
tag: tss_esapi::constants::TPM2_ST_VERIFIED,
hierarchy: tss_esapi::tss2_esys::ESYS_TR_RH_NULL,
digest: tss_esapi::tss2_esys::TPM2B_DIGEST {
size: 32,
buffer: [0; 64],
},
};
*/
let dummy_ticket = get_dummy_ticket(ctx);
(tss_esapi::utils::Digest::try_from(vec![])?, dummy_ticket)
}
Some(policies) => find_and_play_applicable_policy(
ctx,
&policies,
policy_session,
policy_ref.value(),
signkey.get_signing_scheme(),
loaded_key,
)?,
};
ctx.policy_authorize(
policy_session,
approved_policy,
tss_esapi::tss2_esys::TPM2B_DIGEST::try_from(policy_ref)?,
loaded_key_name,
check_ticket,
)?;
next._send_policy(ctx, policy_session)
}
_ => Err(PinError::Text("Policy not implemented")),
}
}
}
fn find_and_play_applicable_policy(
ctx: &mut tss_esapi::Context,
policies: &[SignedPolicy],
policy_session: ESYS_TR,
policy_ref: &[u8],
scheme: utils::AsymSchemeUnion,
loaded_key: ESYS_TR,
) -> Result<
(
tss_esapi::utils::Digest,
tss_esapi::tss2_esys::TPMT_TK_VERIFIED,
),
PinError,
> {
for policy in policies {
if policy.policy_ref != policy_ref {
continue;
}
if let Some(policy_digest) = play_policy(ctx, &policy, policy_session)? {
// aHash ≔ H_{aHashAlg}(approvedPolicy || policyRef)
let mut ahash = Vec::new();
ahash.write_all(&policy_digest)?;
ahash.write_all(&policy_ref)?;
let ahash = ctx
.hash(
&ahash,
tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha256,
tss_esapi::utils::Hierarchy::Null,
)?
.0;
let signature = tss_esapi::utils::Signature {
scheme,
signature: tss_esapi::utils::SignatureData::RsaSignature(policy.signature.clone()),
};
let tkt = ctx.verify_signature(loaded_key, &ahash, &signature.try_into()?)?;
return Ok((policy_digest, tkt));
}
}
Err(PinError::Text("No matching authorized policy found"))
}
// This function would do a simple check whether the policy has a chance for success.
// It does explicitly not change policy_session
fn check_policy_feasibility(_ctx: &mut tss_esapi::Context, _policy: &SignedPolicy) -> Result<bool,PinError> {
Ok(true)
// TODO: Implement this, to check whether the PCRs in this branch would match
}
fn play_policy(
ctx: &mut tss_esapi::Context,
policy: &SignedPolicy,
policy_session: ESYS_TR,
) -> Result<Option<tss_esapi::utils::Digest>, PinError> {
if !check_policy_feasibility(ctx, policy)? {
return Ok(None)
}
for step in &policy.steps {
let tpmstep = TPMPolicyStep::try_from(step)?;
tpmstep._send_policy(ctx, policy_session)?;
}
Ok(Some(ctx.policy_get_digest(policy_session)?))
}
// It turns out that a Null ticket does not work for some TPMs, so let's just generate
// a dummy ticket. This is a valid ticket, but over a totally useless piece of data.
fn get_dummy_ticket(context: &mut tss_esapi::Context) -> tss_esapi::tss2_esys::TPMT_TK_VERIFIED {
let old_ses = context.sessions();
context.set_sessions((ESYS_TR_NONE, ESYS_TR_NONE, ESYS_TR_NONE));
create_and_set_tpm2_session(context, tss_esapi::constants::TPM2_SE_HMAC).unwrap();
let signing_key_pub = utils::create_unrestricted_signing_rsa_public(
tss_esapi::utils::AsymSchemeUnion::RSASSA(
tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha256,
),
2048,
0,
)
.unwrap();
let key_handle = context
.create_primary_key(ESYS_TR_RH_OWNER, &signing_key_pub, &[], &[], &[], &[])
.unwrap();
let ahash = context
.hash(
&[0x1, 0x2],
tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha256,
tss_esapi::utils::Hierarchy::Null,
)
.unwrap()
.0;
let scheme = tss_esapi::tss2_esys::TPMT_SIG_SCHEME {
scheme: tss_esapi::constants::TPM2_ALG_NULL,
details: Default::default(),
};
let validation = tss_esapi::tss2_esys::TPMT_TK_HASHCHECK {
tag: tss_esapi::constants::TPM2_ST_HASHCHECK,
hierarchy: tss_esapi::constants::TPM2_RH_NULL,
digest: Default::default(),
};
// A signature over just the policy_digest, since the policy_ref is empty
let signature = context
.sign(key_handle, &ahash, scheme, &validation)
.unwrap();
let tkt = context
.verify_signature(key_handle, &ahash, &signature.try_into().unwrap())
.unwrap();
context.set_sessions(old_ses);
tkt
}
#[derive(Serialize, Deserialize, std::fmt::Debug)]
struct TPM2Config {
hash: Option<String>,
key: Option<String>,
pcr_bank: Option<String>,
// PCR IDs can be passed in as comma-separated string or json array
pcr_ids: Option<serde_json::Value>,
pcr_digest: Option<String>,
// Public key (in JSON format) for a wildcard policy that's possibly OR'd with the PCR one
policy_pubkey_path: Option<String>,
policy_ref: Option<String>,
policy_path: Option<String>,
}
fn get_authorized_policy_step(
policy_pubkey_path: &str,
policy_path: &Option<String>,
policy_ref: &Option<String>,
) -> Result<TPMPolicyStep, PinError> {
let policy_ref = match policy_ref {
Some(policy_ref) => policy_ref.as_bytes().to_vec(),
None => vec![],
};
let signkey = {
let contents = fs::read_to_string(policy_pubkey_path)?;
serde_json::from_str::<PublicKey>(&contents)?
};
let policies = match policy_path {
None => None,
Some(policy_path) => {
let contents = fs::read_to_string(policy_path)?;
Some(serde_json::from_str::<SignedPolicyList>(&contents)?)
}
};
Ok(TPMPolicyStep::Authorized {
signkey,
policy_ref,
policies,
next: Box::new(TPMPolicyStep::NoStep),
})
}
impl TryFrom<&SignedPolicyStep> for TPMPolicyStep {
type Error = PinError;
fn try_from(spolicy: &SignedPolicyStep) -> Result<Self, PinError> {
match spolicy {
SignedPolicyStep::PCRs{pcr_ids, hash_algorithm, value: _} => {
Ok(TPMPolicyStep::PCRs(
get_pcr_hash_alg_from_name(Some(&hash_algorithm)),
pcr_ids.iter().map(|x| *x as u64).collect(),
Box::new(TPMPolicyStep::NoStep),
))
},
}
}
}
impl TryFrom<&TPM2Config> for TPMPolicyStep {
type Error = PinError;
fn try_from(cfg: &TPM2Config) -> Result<Self, PinError> {
if cfg.pcr_ids.is_some() && cfg.policy_pubkey_path.is_some() {
Ok(TPMPolicyStep::Or([
Box::new(TPMPolicyStep::PCRs(
cfg.get_pcr_hash_alg(),
cfg.get_pcr_ids().unwrap(),
Box::new(TPMPolicyStep::NoStep),
)),
Box::new(get_authorized_policy_step(
cfg.policy_pubkey_path.as_ref().unwrap(),
&None,
&cfg.policy_ref,
)?),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
]))
} else if cfg.pcr_ids.is_some() {
Ok(TPMPolicyStep::PCRs(
cfg.get_pcr_hash_alg(),
cfg.get_pcr_ids().unwrap(),
Box::new(TPMPolicyStep::NoStep),
))
} else if cfg.policy_pubkey_path.is_some() {
get_authorized_policy_step(
cfg.policy_pubkey_path.as_ref().unwrap(),
&None,
&cfg.policy_ref,
)
} else {
Ok(TPMPolicyStep::NoStep)
}
}
}
fn pcr_id_to_slot(pcr: &u64) -> Result<tss_esapi::utils::PcrSlot, PinError> {
match pcr {
0 => Ok(tss_esapi::utils::PcrSlot::Slot0),
1 => Ok(tss_esapi::utils::PcrSlot::Slot1),
2 => Ok(tss_esapi::utils::PcrSlot::Slot2),
3 => Ok(tss_esapi::utils::PcrSlot::Slot3),
4 => Ok(tss_esapi::utils::PcrSlot::Slot4),
5 => Ok(tss_esapi::utils::PcrSlot::Slot5),
6 => Ok(tss_esapi::utils::PcrSlot::Slot6),
7 => Ok(tss_esapi::utils::PcrSlot::Slot7),
8 => Ok(tss_esapi::utils::PcrSlot::Slot8),
9 => Ok(tss_esapi::utils::PcrSlot::Slot9),
10 => Ok(tss_esapi::utils::PcrSlot::Slot10),
11 => Ok(tss_esapi::utils::PcrSlot::Slot11),
12 => Ok(tss_esapi::utils::PcrSlot::Slot12),
13 => Ok(tss_esapi::utils::PcrSlot::Slot13),
14 => Ok(tss_esapi::utils::PcrSlot::Slot14),
15 => Ok(tss_esapi::utils::PcrSlot::Slot15),
16 => Ok(tss_esapi::utils::PcrSlot::Slot16),
17 => Ok(tss_esapi::utils::PcrSlot::Slot17),
18 => Ok(tss_esapi::utils::PcrSlot::Slot18),
19 => Ok(tss_esapi::utils::PcrSlot::Slot19),
20 => Ok(tss_esapi::utils::PcrSlot::Slot20),
21 => Ok(tss_esapi::utils::PcrSlot::Slot21),
22 => Ok(tss_esapi::utils::PcrSlot::Slot22),
23 => Ok(tss_esapi::utils::PcrSlot::Slot23),
_ => Err(PinError::Text("Invalid PCR slot requested")),
}
}
fn get_pcr_hash_alg_from_name(
name: Option<&String>,
) -> tss_esapi::utils::algorithm_specifiers::HashingAlgorithm {
match name {
None => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha256,
Some(val) => match val.to_lowercase().as_str() {
"sha1" => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha1,
"sha256" => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha256,
"sha384" => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha384,
"sha512" => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha512,
_ => panic!(format!("Unsupported hash algo: {:?}", name)),
},
}
}
impl TPM2Config {
fn get_pcr_hash_alg(&self) -> tss_esapi::utils::algorithm_specifiers::HashingAlgorithm {
get_pcr_hash_alg_from_name(self.pcr_bank.as_ref())
}
fn get_pcr_ids(&self) -> Option<Vec<u64>> {
match &self.pcr_ids {
None => None,
Some(serde_json::Value::Array(vals)) => {
Some(vals.iter().map(|x| x.as_u64().unwrap()).collect())
}
_ => panic!("Unexpected type found for pcr_ids"),
}
}
fn get_pcr_ids_str(&self) -> Option<String> {
match &self.pcr_ids {
None => None,
Some(serde_json::Value::Array(vals)) => Some(
vals.iter()
.map(|x| x.as_u64().unwrap().to_string())
.collect::<Vec<String>>()
.join(","),
),
_ => panic!("Unexpected type found for pcr_ids"),
}
}
fn normalize(mut self) -> Result<TPM2Config, PinError> {
self.normalize_pcr_ids()?;
if self.pcr_ids.is_some() && self.pcr_bank.is_none() {
self.pcr_bank = Some("sha256".to_string());
}
if (self.policy_pubkey_path.is_some()
|| self.policy_path.is_some()
|| self.policy_ref.is_some())
&& (self.policy_pubkey_path.is_none()
|| self.policy_path.is_none()
|| self.policy_ref.is_none())
{
return Err(PinError::Text(
"Not all of policy pubkey, path and ref are specified",
));
}
Ok(self)
}
fn normalize_pcr_ids(&mut self) -> Result<(), PinError> {
// Normalize pcr_ids from comma-separated string to array
if let Some(serde_json::Value::String(val)) = &self.pcr_ids {
// Was a string, do a split
let newval: Vec<serde_json::Value> = val
.split(',')
.map(|x| serde_json::Value::String(x.to_string()))
.collect();
self.pcr_ids = Some(serde_json::Value::Array(newval));
}
// Normalize pcr_ids from array of Strings to array of Numbers
if let Some(serde_json::Value::Array(vals)) = &self.pcr_ids {
let newvals: Result<Vec<serde_json::Value>, _> = vals
.iter()
.map(|x| match x {
serde_json::Value::String(val) => match val.parse::<serde_json::Number>() {
Ok(res) => {
let new = serde_json::Value::Number(res);
if !new.is_u64() {
return Err("Non-positive string int");
}
Ok(new)
}
Err(_) => Err("Unparseable string int"),
},
serde_json::Value::Number(n) => {
let new = serde_json::Value::Number(n.clone());
if !new.is_u64() {
return Err("Non-positive int");
}
Ok(new)
}
_ => Err("Invalid value in pcr_ids"),
})
.collect();
self.pcr_ids = Some(serde_json::Value::Array(newvals?));
}
match &self.pcr_ids {
None => Ok(()),
// The normalization above would've caught any non-ints
Some(serde_json::Value::Array(_)) => Ok(()),
_ => Err(PinError::Text("Invalid type")),
}
}
}
// if ! tpm2_createprimary -Q -H "$auth" -g "$hash" -G "$key" -C "$TMP"/primary.context; then
#[derive(Debug)]
enum ActionMode {
Encrypt,
Decrypt,
}
fn get_mode_and_cfg(args: &[String]) -> Result<(ActionMode, Option<TPM2Config>), PinError> {
let (mode, cfgstr) = if args[0].contains("encrypt") && args.len() == 2 {
(ActionMode::Encrypt, Some(&args[1]))
} else if args[0].contains("decrypt") {
(ActionMode::Decrypt, None)
} else if args.len() > 1 {
if args[1] == "encrypt" && args.len() == 3 {
(ActionMode::Encrypt, Some(&args[2]))
} else if args[1] == "decrypt" {
(ActionMode::Decrypt, None)
} else {
return Err(PinError::NoCommand);
}
} else {
return Err(PinError::NoCommand);
};
let cfg: Option<TPM2Config> = match cfgstr {
None => None,
Some(cfgstr) => Some(serde_json::from_str::<TPM2Config>(cfgstr)?.normalize()?),
};
Ok((mode, cfg))
}
fn create_tpm2b_public_sealed_object(
policy: Option<tss_esapi::utils::Digest>,
) -> Result<tss_esapi::tss2_esys::TPM2B_PUBLIC, PinError> {
let mut object_attributes = utils::ObjectAttributes(0);
object_attributes.set_fixed_tpm(true);
object_attributes.set_fixed_parent(true);
object_attributes.set_no_da(true);
object_attributes.set_admin_with_policy(true);
if policy.is_none() {
object_attributes.set_user_with_auth(true);
}
let policy = match policy {
Some(p) => p,
None => tss_esapi::utils::Digest::try_from(vec![])?,
};
let mut params: tss_esapi::tss2_esys::TPMU_PUBLIC_PARMS = Default::default();
params.keyedHashDetail.scheme.scheme = tss_esapi::constants::TPM2_ALG_NULL;
Ok(tss_esapi::tss2_esys::TPM2B_PUBLIC {
size: std::mem::size_of::<tss_esapi::tss2_esys::TPMT_PUBLIC>() as u16,
publicArea: tss_esapi::tss2_esys::TPMT_PUBLIC {
type_: tss_esapi::constants::TPM2_ALG_KEYEDHASH,
nameAlg: tss_esapi::constants::TPM2_ALG_SHA256,
objectAttributes: object_attributes.0,
authPolicy: tss_esapi::tss2_esys::TPM2B_DIGEST::try_from(policy)?,
parameters: params,
unique: Default::default(),
},
})
}
fn perform_encrypt(cfg: TPM2Config, input: &str) -> Result<(), PinError> {
let key_type = match &cfg.key {
None => "ecc",
Some(key_type) => key_type,
};
let key_public = get_key_public(&key_type)?;
let mut ctx = get_tpm2_ctx()?;
let key_handle = get_tpm2_primary_key(&mut ctx, &key_public)?;
let policy_runner: TPMPolicyStep = TPMPolicyStep::try_from(&cfg)?;
let pin_type = match policy_runner {
TPMPolicyStep::NoStep => "tpm2",
TPMPolicyStep::PCRs(_, _, _) => "tpm2",
_ => "tpm2plus",
};
let policy_digest = policy_runner.send_policy(&mut ctx, true)?;
let key_bytes: Vec<u8> = ctx.get_random(32)?;
let mut jwk = biscuit::jwk::JWK::new_octet_key(&key_bytes, biscuit::Empty {});
jwk.common.algorithm = Some(biscuit::jwa::Algorithm::ContentEncryption(
biscuit::jwa::ContentEncryptionAlgorithm::A256GCM,
));
jwk.common.key_operations = Some(vec![
biscuit::jwk::KeyOperations::Encrypt,
biscuit::jwk::KeyOperations::Decrypt,
]);
let jwk_str = serde_json::to_string(&jwk)?;
let public = create_tpm2b_public_sealed_object(policy_digest)?;
let (jwk_priv, jwk_pub) =
ctx.create_key(key_handle, &public, &[], jwk_str.as_bytes(), &[], &[])?;
let jwk_priv = get_tpm2b_private(jwk_priv)?;
let jwk_pub = get_tpm2b_public(jwk_pub)?;
let hdr: biscuit::jwe::Header<ClevisHeader> = biscuit::jwe::Header {
registered: biscuit::jwe::RegisteredHeader {
cek_algorithm: biscuit::jwa::KeyManagementAlgorithm::DirectSymmetricKey,
enc_algorithm: biscuit::jwa::ContentEncryptionAlgorithm::A256GCM,
compression_algorithm: None,
media_type: None,
content_type: None,
web_key_url: None,
web_key: None,
key_id: None,
x509_url: None,
x509_chain: None,
x509_fingerprint: None,
critical: None,
},
cek_algorithm: biscuit::jwe::CekAlgorithmHeader {
nonce: None,
tag: None,
},
private: ClevisHeader {
clevis: ClevisInner {
pin: pin_type.to_string(),
tpm2: Tpm2Inner {
hash: "sha256".to_string(),
key: key_type.to_string(),
jwk_pub,
jwk_priv,
pcr_bank: cfg.pcr_bank.clone(),
pcr_ids: cfg.get_pcr_ids_str(),
policy_pubkey_path: cfg.policy_pubkey_path,
policy_ref: cfg.policy_ref,
policy_path: cfg.policy_path,
},
},
},
};
let rand_nonce = ctx.get_random(12)?;
let jwe_enc_options = biscuit::jwa::EncryptionOptions::AES_GCM { nonce: rand_nonce };
let jwe_token = biscuit::jwe::Compact::new_decrypted(hdr, input.as_bytes().to_vec());
let jwe_token_compact = jwe_token.encrypt(&jwk, &jwe_enc_options)?;
let encoded_token = jwe_token_compact.encrypted()?.encode();
io::stdout().write_all(encoded_token.as_bytes())?;
Ok(())
}
#[derive(Debug, Serialize, Deserialize, Clone)]
struct Tpm2Inner {
hash: String,
#[serde(
deserialize_with = "deserialize_as_base64_url_no_pad",
serialize_with = "serialize_as_base64_url_no_pad"
)]
jwk_priv: Vec<u8>,
#[serde(
deserialize_with = "deserialize_as_base64_url_no_pad",
serialize_with = "serialize_as_base64_url_no_pad"
)]
jwk_pub: Vec<u8>,
key: String,
// PCR Binding may be specified, may not
#[serde(skip_serializing_if = "Option::is_none")]
pcr_bank: Option<String>,
#[serde(skip_serializing_if = "Option::is_none")]
pcr_ids: Option<String>,
// Public key (in PEM format) for a wildcard policy that's OR'd with the PCR one
#[serde(skip_serializing_if = "Option::is_none")]
policy_pubkey_path: Option<String>,
#[serde(skip_serializing_if = "Option::is_none")]
policy_ref: Option<String>,
#[serde(skip_serializing_if = "Option::is_none")]
policy_path: Option<String>,
}
impl Tpm2Inner {
fn get_pcr_ids(&self) -> Option<Vec<u64>> {
Some(
self.pcr_ids
.as_ref()?
.split(',')
.map(|x| x.parse::<u64>().unwrap())
.collect(),
)
}
}
impl TryFrom<&Tpm2Inner> for TPMPolicyStep {
type Error = PinError;
fn try_from(cfg: &Tpm2Inner) -> Result<Self, PinError> {
if cfg.pcr_ids.is_some() && cfg.policy_pubkey_path.is_some() {
Ok(TPMPolicyStep::Or([
Box::new(TPMPolicyStep::PCRs(
get_pcr_hash_alg_from_name(cfg.pcr_bank.as_ref()),
cfg.get_pcr_ids().unwrap(),
Box::new(TPMPolicyStep::NoStep),
)),
Box::new(get_authorized_policy_step(
cfg.policy_pubkey_path.as_ref().unwrap(),
&cfg.policy_path,
&cfg.policy_ref,
)?),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
Box::new(TPMPolicyStep::NoStep),
]))
} else if cfg.pcr_ids.is_some() {
Ok(TPMPolicyStep::PCRs(
get_pcr_hash_alg_from_name(cfg.pcr_bank.as_ref()),
cfg.get_pcr_ids().unwrap(),
Box::new(TPMPolicyStep::NoStep),
))
} else if cfg.policy_pubkey_path.is_some() {
get_authorized_policy_step(
cfg.policy_pubkey_path.as_ref().unwrap(),
&cfg.policy_path,
&cfg.policy_ref,
)
} else {
Ok(TPMPolicyStep::NoStep)
}
}
}
#[derive(Debug, Serialize, Deserialize, Clone)]
struct ClevisInner {
pin: String,
tpm2: Tpm2Inner,
}
#[derive(Debug, Serialize, Deserialize, Clone)]
struct ClevisHeader {
clevis: ClevisInner,
}
impl CompactJson for Tpm2Inner {}
impl CompactJson for ClevisHeader {}
impl CompactJson for ClevisInner {}
fn get_tpm2b_public(val: tss_esapi::tss2_esys::TPM2B_PUBLIC) -> Result<Vec<u8>, PinError> {
let mut offset = 0 as u64;
let mut resp = Vec::with_capacity((val.size + 4) as usize);
unsafe {
let res = tss_esapi::tss2_esys::Tss2_MU_TPM2B_PUBLIC_Marshal(
&val,
resp.as_mut_ptr(),
resp.capacity() as u64,
&mut offset,
);
if res != 0 {
return Err(PinError::Text("Marshalling tpm2b_public failed"));
}
resp.set_len(offset as usize);
}
Ok(resp)
}
fn get_tpm2b_private(val: tss_esapi::tss2_esys::TPM2B_PRIVATE) -> Result<Vec<u8>, PinError> {
let mut offset = 0 as u64;
let mut resp = Vec::with_capacity((val.size + 4) as usize);
unsafe {
let res = tss_esapi::tss2_esys::Tss2_MU_TPM2B_PRIVATE_Marshal(
&val,
resp.as_mut_ptr(),
resp.capacity() as u64,
&mut offset,
);
if res != 0 {
return Err(PinError::Text("Marshalling tpm2b_private failed"));
}
resp.set_len(offset as usize);
}
Ok(resp)
}
fn build_tpm2b_private(val: &[u8]) -> Result<tss_esapi::tss2_esys::TPM2B_PRIVATE, PinError> {
let mut resp = tss_esapi::tss2_esys::TPM2B_PRIVATE::default();
let mut offset = 0 as u64;
unsafe {
let res = tss_esapi::tss2_esys::Tss2_MU_TPM2B_PRIVATE_Unmarshal(
val[..].as_ptr(),
val.len() as u64,
&mut offset,
&mut resp,
);
if res != 0 {
return Err(PinError::Text("Unmarshalling tpm2b_private failed"));
}
}
Ok(resp)
}
fn build_tpm2b_public(val: &[u8]) -> Result<tss_esapi::tss2_esys::TPM2B_PUBLIC, PinError> {
let mut resp = tss_esapi::tss2_esys::TPM2B_PUBLIC::default();
let mut offset = 0 as u64;
unsafe {
let res = tss_esapi::tss2_esys::Tss2_MU_TPM2B_PUBLIC_Unmarshal(
val[..].as_ptr(),
val.len() as u64,
&mut offset,
&mut resp,
);
if res != 0 {
return Err(PinError::Text("Unmarshalling tpm2b_public failed"));
}
}
Ok(resp)
}
fn create_restricted_ecc_public() -> tss_esapi::tss2_esys::TPM2B_PUBLIC {
let ecc_params = utils::TpmsEccParmsBuilder::new_restricted_decryption_key(
utils::algorithm_specifiers::Cipher::aes_128_cfb(),
utils::algorithm_specifiers::EllipticCurve::NistP256,
)
.build()
.unwrap();
let mut object_attributes = utils::ObjectAttributes(0);
object_attributes.set_fixed_tpm(true);
object_attributes.set_fixed_parent(true);
object_attributes.set_sensitive_data_origin(true);
object_attributes.set_user_with_auth(true);
object_attributes.set_decrypt(true);
object_attributes.set_sign_encrypt(false);
object_attributes.set_restricted(true);
utils::Tpm2BPublicBuilder::new()
.with_type(constants::TPM2_ALG_ECC)
.with_name_alg(constants::TPM2_ALG_SHA256)
.with_object_attributes(object_attributes)
.with_parms(utils::PublicParmsUnion::EccDetail(ecc_params))
.build()
.unwrap()
}
fn get_key_public(key_type: &str) -> Result<tss_esapi::tss2_esys::TPM2B_PUBLIC, PinError> {
match key_type {
"ecc" => Ok(create_restricted_ecc_public()),
"rsa" => Ok(tss_esapi::utils::create_restricted_decryption_rsa_public(
utils::algorithm_specifiers::Cipher::aes_128_cfb(),
2048,
0,
)?),
_ => Err(PinError::Text("Unsupported key type used")),
}
}
#[derive(Debug, Serialize, Deserialize)]
enum SignedPolicyStep {
PCRs {
pcr_ids: Vec<u16>,
hash_algorithm: String,
#[serde(
deserialize_with = "deserialize_as_base64",
serialize_with = "serialize_as_base64"
)]
value: Vec<u8>,
},
}
#[derive(Debug, Serialize, Deserialize)]
struct SignedPolicy {
// policy_ref contains the policy_ref used in the aHash, used to determine the policy to use from a list
#[serde(
deserialize_with = "deserialize_as_base64",
serialize_with = "serialize_as_base64"
)]
policy_ref: Vec<u8>,
// steps contains the policy steps that are signed
steps: Vec<SignedPolicyStep>,
// signature contains the signature over aHash
#[serde(
deserialize_with = "deserialize_as_base64",
serialize_with = "serialize_as_base64"
)]
signature: Vec<u8>,
}
type SignedPolicyList = Vec<SignedPolicy>;
#[derive(Debug, Serialize, Deserialize)]
enum RSAPublicKeyScheme {
RSAPSS,
RSASSA,
}
impl RSAPublicKeyScheme {
fn to_scheme(&self, hash_algo: &HashAlgo) -> tss_esapi::utils::AsymSchemeUnion {
match self {
RSAPublicKeyScheme::RSAPSS => {
tss_esapi::utils::AsymSchemeUnion::RSAPSS(hash_algo.into())
}
RSAPublicKeyScheme::RSASSA => {
tss_esapi::utils::AsymSchemeUnion::RSASSA(hash_algo.into())
}
}
}
}
#[derive(Debug, Serialize, Deserialize)]
pub enum HashAlgo {
SHA1,
SHA256,
SHA384,
SHA512,
SM3_256,
SHA3_256,
SHA3_384,
SHA3_512,
}
impl HashAlgo {
fn to_tpmi_alg_hash(&self) -> tss_esapi::tss2_esys::TPMI_ALG_HASH {
let alg: tss_esapi::utils::algorithm_specifiers::HashingAlgorithm = self.into();
alg.into()
}
}
impl From<&HashAlgo> for tss_esapi::utils::algorithm_specifiers::HashingAlgorithm {
fn from(halg: &HashAlgo) -> Self {
match halg {
HashAlgo::SHA1 => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha1,
HashAlgo::SHA256 => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha256,
HashAlgo::SHA384 => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha384,
HashAlgo::SHA512 => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha512,
HashAlgo::SM3_256 => tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sm3_256,
HashAlgo::SHA3_256 => {
tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha3_256
}
HashAlgo::SHA3_384 => {
tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha3_384
}
HashAlgo::SHA3_512 => {
tss_esapi::utils::algorithm_specifiers::HashingAlgorithm::Sha3_512
}
}
}
}
#[derive(Debug, Serialize, Deserialize)]
enum PublicKey {
RSA {
scheme: RSAPublicKeyScheme,
hashing_algo: HashAlgo,
exponent: u32,
#[serde(
deserialize_with = "deserialize_as_base64_url_no_pad",
serialize_with = "serialize_as_base64_url_no_pad"
)]
modulus: Vec<u8>,
},
}
impl PublicKey {
fn get_signing_scheme(&self) -> tss_esapi::utils::AsymSchemeUnion {
match self {
PublicKey::RSA {
scheme,
hashing_algo,
exponent: _,
modulus: _,
} => scheme.to_scheme(hashing_algo),
}
}
}
impl TryFrom<&PublicKey> for tss_esapi::tss2_esys::TPM2B_PUBLIC {
type Error = PinError;
fn try_from(publickey: &PublicKey) -> Result<Self, Self::Error> {
match publickey {
PublicKey::RSA {
scheme,
hashing_algo,
modulus,
exponent,
} => {
let mut object_attributes = tss_esapi::utils::ObjectAttributes(0);
object_attributes.set_fixed_tpm(false);
object_attributes.set_fixed_parent(false);
object_attributes.set_sensitive_data_origin(false);
object_attributes.set_user_with_auth(true);
object_attributes.set_decrypt(false);
object_attributes.set_sign_encrypt(true);
object_attributes.set_restricted(false);
let len = modulus.len();
let mut buffer = [0_u8; 512];
buffer[..len].clone_from_slice(&modulus[..len]);
let rsa_uniq = Box::new(tss_esapi::tss2_esys::TPM2B_PUBLIC_KEY_RSA {
size: len as u16,
buffer,
});
Ok(tss_esapi::utils::Tpm2BPublicBuilder::new()
.with_type(tss_esapi::constants::TPM2_ALG_RSA)
.with_name_alg(hashing_algo.to_tpmi_alg_hash())
.with_parms(tss_esapi::utils::PublicParmsUnion::RsaDetail(
tss_esapi::utils::TpmsRsaParmsBuilder::new_unrestricted_signing_key(
scheme.to_scheme(&hashing_algo),
(modulus.len() * 8) as u16,
*exponent,
)
.build()?,
))
.with_object_attributes(object_attributes)
.with_unique(tss_esapi::utils::PublicIdUnion::Rsa(rsa_uniq))
.build()?)
}
}
}
}
fn perform_decrypt(input: &str) -> Result<(), PinError> {
let token = biscuit::Compact::decode(input.trim());
let hdr: biscuit::jwe::Header<ClevisHeader> = token.part(0)?;
if hdr.private.clevis.pin != "tpm2" && hdr.private.clevis.pin != "tpm2plus" {
return Err(PinError::Text("JWE pin mismatch"));
}
let jwkpub = build_tpm2b_public(&hdr.private.clevis.tpm2.jwk_pub)?;
let jwkpriv = build_tpm2b_private(&hdr.private.clevis.tpm2.jwk_priv)?;
let policy = TPMPolicyStep::try_from(&hdr.private.clevis.tpm2)?;
let key_public = get_key_public(hdr.private.clevis.tpm2.key.as_str())?;
let mut ctx = get_tpm2_ctx()?;
let key_handle = get_tpm2_primary_key(&mut ctx, &key_public)?;
create_and_set_tpm2_session(&mut ctx, tss_esapi::constants::TPM2_SE_HMAC)?;
let key = ctx.load(key_handle, jwkpriv, jwkpub)?;
policy.send_policy(&mut ctx, false)?;
let unsealed = ctx.unseal(key)?;
let unsealed = &unsealed.value();
let unsealed = std::str::from_utf8(unsealed)?;
let jwk: biscuit::jwk::JWK<biscuit::Empty> = serde_json::from_str(unsealed)?;
let token: biscuit::jwe::Compact<Vec<u8>, biscuit::Empty> = jwe::Compact::Encrypted(token);
let token = token.decrypt(
&jwk,
biscuit::jwa::KeyManagementAlgorithm::DirectSymmetricKey,
biscuit::jwa::ContentEncryptionAlgorithm::A256GCM,
)?;
// We just decrypted the token, there should be a payload
let payload = token.payload()?;
io::stdout().write_all(payload)?;
Ok(())
}
fn read_input_token() -> Result<String, PinError> {
let mut buffer = String::new();
io::stdin().read_to_string(&mut buffer)?;
if buffer.is_empty() {
return Err(PinError::Text("No data provided"));
}
Ok(buffer)
}
fn main() {
let args: Vec<String> = env::args().collect();
let (mode, cfg) = match get_mode_and_cfg(&args) {
Err(e) => {
eprintln!("Error during parsing operation: {}", e);
std::process::exit(1);
}
Ok((mode, cfg)) => (mode, cfg),
};
let input = match read_input_token() {
Err(e) => {
eprintln!("Error getting input token: {}", e);
std::process::exit(1);
}
Ok(input) => input,
};
if let Err(e) = match mode {
ActionMode::Encrypt => perform_encrypt(cfg.unwrap(), &input),
ActionMode::Decrypt => perform_decrypt(&input),
} {
eprintln!("Error executing command: {}", e);
std::process::exit(2);
}
}
fn get_tpm2_ctx() -> Result<Context, tss_esapi::response_code::Error> {
unsafe { Context::new(tcti::Tcti::Tabrmd(Default::default())) }
}
fn get_tpm2_primary_key(
ctx: &mut Context,
pub_template: &tss_esapi::tss2_esys::TPM2B_PUBLIC,
) -> Result<ESYS_TR, PinError> {
let cur_sessions = ctx.sessions();
create_and_set_tpm2_session(ctx, tss_esapi::constants::TPM2_SE_HMAC)?;
let key_handle = ctx.create_primary_key(ESYS_TR_RH_OWNER, pub_template, &[], &[], &[], &[])?;
ctx.set_sessions(cur_sessions);
Ok(key_handle)
}
Reference in a new issue View git blame Copy permalink