tests/test_aggregator.py
| 1 | """Tests for FederatedAggregator, AggregationRound, and AggregationProof.""" |
| 2 | |
| 3 | from __future__ import annotations |
| 4 | |
| 5 | import pytest |
| 6 | from quantumshield.identity.agent import AgentIdentity |
| 7 | |
| 8 | from pqc_federated_learning import ( |
| 9 | AggregationRound, |
| 10 | FedAvgAggregator, |
| 11 | FederatedAggregator, |
| 12 | ) |
| 13 | from pqc_federated_learning.errors import ( |
| 14 | AggregationError, |
| 15 | InsufficientUpdatesError, |
| 16 | ) |
| 17 | from tests.conftest import make_signed_update |
| 18 | |
| 19 | |
| 20 | def test_verified_updates_aggregate( |
| 21 | aggregator_identity: AgentIdentity, |
| 22 | client_a_identity: AgentIdentity, |
| 23 | client_b_identity: AgentIdentity, |
| 24 | ) -> None: |
| 25 | a = make_signed_update(client_a_identity) |
| 26 | b = make_signed_update(client_b_identity) |
| 27 | round_ = AggregationRound(round_id="round-1", model_id="model-x") |
| 28 | round_.add(a) |
| 29 | round_.add(b) |
| 30 | |
| 31 | agg = FederatedAggregator( |
| 32 | identity=aggregator_identity, strategy=FedAvgAggregator() |
| 33 | ) |
| 34 | result = agg.aggregate(round_) |
| 35 | assert len(result.aggregated) == 2 |
| 36 | assert result.proof.num_tensors == 2 |
| 37 | assert result.proof.signature != "" |
| 38 | assert set(result.proof.included_client_dids) == { |
| 39 | client_a_identity.did, |
| 40 | client_b_identity.did, |
| 41 | } |
| 42 | assert not result.proof.excluded_reasons |
| 43 | |
| 44 | |
| 45 | def test_unsigned_update_excluded( |
| 46 | aggregator_identity: AgentIdentity, |
| 47 | client_a_identity: AgentIdentity, |
| 48 | client_b_identity: AgentIdentity, |
| 49 | ) -> None: |
| 50 | good = make_signed_update(client_a_identity) |
| 51 | bad = make_signed_update(client_b_identity) |
| 52 | # Strip signature from bad |
| 53 | bad.signature = "" |
| 54 | |
| 55 | round_ = AggregationRound(round_id="round-1", model_id="model-x") |
| 56 | round_.add(good) |
| 57 | round_.add(bad) |
| 58 | |
| 59 | agg = FederatedAggregator( |
| 60 | identity=aggregator_identity, strategy=FedAvgAggregator() |
| 61 | ) |
| 62 | result = agg.aggregate(round_) |
| 63 | assert client_a_identity.did in result.proof.included_client_dids |
| 64 | assert client_b_identity.did in result.proof.excluded_reasons |
| 65 | |
| 66 | |
| 67 | def test_untrusted_client_excluded( |
| 68 | aggregator_identity: AgentIdentity, |
| 69 | client_a_identity: AgentIdentity, |
| 70 | attacker_identity: AgentIdentity, |
| 71 | ) -> None: |
| 72 | good = make_signed_update(client_a_identity) |
| 73 | attacker = make_signed_update(attacker_identity) |
| 74 | |
| 75 | round_ = AggregationRound(round_id="round-1", model_id="model-x") |
| 76 | round_.add(good) |
| 77 | round_.add(attacker) |
| 78 | |
| 79 | agg = FederatedAggregator( |
| 80 | identity=aggregator_identity, |
| 81 | strategy=FedAvgAggregator(), |
| 82 | trusted_clients={client_a_identity.did}, |
| 83 | ) |
| 84 | result = agg.aggregate(round_) |
| 85 | assert client_a_identity.did in result.proof.included_client_dids |
| 86 | assert attacker_identity.did in result.proof.excluded_reasons |
| 87 | assert result.proof.excluded_reasons[attacker_identity.did] == "client not in trusted set" |
| 88 | |
| 89 | |
| 90 | def test_min_updates_enforced( |
| 91 | aggregator_identity: AgentIdentity, |
| 92 | client_a_identity: AgentIdentity, |
| 93 | ) -> None: |
| 94 | a = make_signed_update(client_a_identity) |
| 95 | round_ = AggregationRound(round_id="round-1", model_id="model-x") |
| 96 | round_.add(a) |
| 97 | |
| 98 | agg = FederatedAggregator( |
| 99 | identity=aggregator_identity, |
| 100 | strategy=FedAvgAggregator(), |
| 101 | min_updates=2, |
| 102 | ) |
| 103 | with pytest.raises(InsufficientUpdatesError): |
| 104 | agg.aggregate(round_) |
| 105 | |
| 106 | |
| 107 | def test_proof_signed_and_verifiable( |
| 108 | aggregator_identity: AgentIdentity, |
| 109 | client_a_identity: AgentIdentity, |
| 110 | client_b_identity: AgentIdentity, |
| 111 | ) -> None: |
| 112 | a = make_signed_update(client_a_identity) |
| 113 | b = make_signed_update(client_b_identity) |
| 114 | round_ = AggregationRound(round_id="round-1", model_id="model-x") |
| 115 | round_.add(a) |
| 116 | round_.add(b) |
| 117 | |
| 118 | agg = FederatedAggregator( |
| 119 | identity=aggregator_identity, strategy=FedAvgAggregator() |
| 120 | ) |
| 121 | result = agg.aggregate(round_) |
| 122 | assert FederatedAggregator.verify_proof(result.proof) is True |
| 123 | assert result.proof.signer_did == aggregator_identity.did |
| 124 | |
| 125 | |
| 126 | def test_tampered_proof_rejected( |
| 127 | aggregator_identity: AgentIdentity, |
| 128 | client_a_identity: AgentIdentity, |
| 129 | client_b_identity: AgentIdentity, |
| 130 | ) -> None: |
| 131 | a = make_signed_update(client_a_identity) |
| 132 | b = make_signed_update(client_b_identity) |
| 133 | round_ = AggregationRound(round_id="round-1", model_id="model-x") |
| 134 | round_.add(a) |
| 135 | round_.add(b) |
| 136 | |
| 137 | agg = FederatedAggregator( |
| 138 | identity=aggregator_identity, strategy=FedAvgAggregator() |
| 139 | ) |
| 140 | result = agg.aggregate(round_) |
| 141 | # Flip result hash |
| 142 | result.proof.result_hash = "0" * 64 |
| 143 | assert FederatedAggregator.verify_proof(result.proof) is False |
| 144 | |
| 145 | |
| 146 | def test_round_add_validates_round_and_model( |
| 147 | client_a_identity: AgentIdentity, |
| 148 | ) -> None: |
| 149 | round_ = AggregationRound(round_id="round-1", model_id="model-x") |
| 150 | |
| 151 | wrong_round = make_signed_update(client_a_identity, round_id="round-2", model_id="model-x") |
| 152 | with pytest.raises(AggregationError): |
| 153 | round_.add(wrong_round) |
| 154 | |
| 155 | wrong_model = make_signed_update(client_a_identity, round_id="round-1", model_id="model-y") |
| 156 | with pytest.raises(AggregationError): |
| 157 | round_.add(wrong_model) |
| 158 | |
| 159 | |
| 160 | def test_proof_roundtrip_to_dict( |
| 161 | aggregator_identity: AgentIdentity, |
| 162 | client_a_identity: AgentIdentity, |
| 163 | client_b_identity: AgentIdentity, |
| 164 | ) -> None: |
| 165 | a = make_signed_update(client_a_identity) |
| 166 | b = make_signed_update(client_b_identity) |
| 167 | round_ = AggregationRound(round_id="round-1", model_id="model-x") |
| 168 | round_.add(a) |
| 169 | round_.add(b) |
| 170 | |
| 171 | agg = FederatedAggregator( |
| 172 | identity=aggregator_identity, strategy=FedAvgAggregator() |
| 173 | ) |
| 174 | result = agg.aggregate(round_) |
| 175 | from pqc_federated_learning import AggregationProof |
| 176 | |
| 177 | d = result.proof.to_dict() |
| 178 | proof2 = AggregationProof.from_dict(d) |
| 179 | assert FederatedAggregator.verify_proof(proof2) is True |
| 180 | |