92 lines
2.0 KiB
C++
92 lines
2.0 KiB
C++
#include "receiver.h"
|
|
|
|
#include <sodium.h>
|
|
|
|
#include "json.hpp"
|
|
|
|
#include "expiring_signature.h"
|
|
#include "sodium_helpers.h"
|
|
#include "string_helpers.h"
|
|
#include "time_helpers.h"
|
|
|
|
namespace BareMinimumCrypto::Receiver {
|
|
using nlohmann::json;
|
|
|
|
bool is_pubkey_length (const vector <uint8_t> & v) {
|
|
return v.size () == crypto_sign_PUBLICKEYBYTES;
|
|
}
|
|
|
|
optional <vector <uint8_t>> try_verify_signed_data (
|
|
const ExpiringSignature & sig,
|
|
const vector <uint8_t> & pubkey,
|
|
Instant now
|
|
) {
|
|
try_sodium_init ();
|
|
|
|
if (! is_pubkey_length (pubkey)) {
|
|
return nullopt;
|
|
}
|
|
|
|
if (crypto_sign_verify_detached (
|
|
sig.sig.data (),
|
|
(const uint8_t *)sig.cert_s.data (),
|
|
sig.cert_s.size (),
|
|
pubkey.data ()
|
|
) != 0) {
|
|
return nullopt;
|
|
}
|
|
|
|
const json j = json::parse (sig.cert_s);
|
|
|
|
const TimeRange tr {
|
|
j ["not_before"],
|
|
j ["not_after"]
|
|
};
|
|
|
|
if (! tr.contains (now)) {
|
|
return nullopt;
|
|
}
|
|
|
|
const string payload_b64 = j ["payload_b64"];
|
|
const auto payload = std::move (*BareMinimumCrypto::base64_decode (payload_b64));
|
|
|
|
return payload;
|
|
}
|
|
|
|
optional <vector <uint8_t>> verify_signed_data (
|
|
const ExpiringSignature & sig,
|
|
const vector <uint8_t> & pubkey,
|
|
Instant now
|
|
) {
|
|
try {
|
|
return try_verify_signed_data (sig, pubkey, now);
|
|
}
|
|
catch (json::exception &) {
|
|
return nullopt;
|
|
}
|
|
}
|
|
|
|
optional <vector <uint8_t>> verify_cert_and_data (
|
|
const ExpiringSignature & signed_cert,
|
|
const ExpiringSignature & signed_data,
|
|
const vector <uint8_t> & root_pubkey,
|
|
Instant now
|
|
) {
|
|
auto subkey_opt = verify_signed_data (signed_cert, root_pubkey, now);
|
|
if (! subkey_opt) {
|
|
return nullopt;
|
|
}
|
|
const auto subkey = std::move (*subkey_opt);
|
|
|
|
return verify_signed_data (signed_data, subkey, now);
|
|
}
|
|
|
|
optional <vector <uint8_t>> verify_cert_and_data (
|
|
const ExpiringSignature & signed_cert,
|
|
const ExpiringSignature & signed_data,
|
|
const vector <uint8_t> & root_pubkey
|
|
) {
|
|
return verify_cert_and_data (signed_cert, signed_data, root_pubkey, Instant::now ());
|
|
}
|
|
}
|