feat(access-control-prover): 10.1 abstract dominance relations without prover fallback

This commit is contained in:
Marius Ciepluch
2026-10-29 19:01:25 +01:00
parent f23d3f986d
commit 8ad304ffeb
3 changed files with 249 additions and 2 deletions
+1 -1
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@@ -165,7 +165,7 @@ its final resolution, dominance, fact-acquisition and measurement semantics with
- _Depends: 9.3_
- [ ] 10. Strict authorization judgment
- [ ] 10.1 Return abstract dominance relations without prover fallback
- [x] 10.1 Return abstract dominance relations without prover fallback
- Return MUST, MAY, NO or UNKNOWN with guard effect and control context.
- Keep legacy order dominance unchanged, but return UNKNOWN in prover mode for unavailable graphs or line mappings.
- Done when no prover fixture is discharged or flagged solely through textual-order fallback.
@@ -16,9 +16,11 @@ from __future__ import annotations
import re
from collections.abc import Mapping, Sequence
from dataclasses import dataclass
from typing import Any
from ..cfg import ControlContext, FunctionCfg
from .abstract_domain import EvidenceRelation
from .dominance import Dominance, OrderDominance
from .operations import Discharge, Operation
@@ -31,6 +33,15 @@ _EXIT_LINE = re.compile(r"^\s*(?P<word>return\b|raise\b|throw\b|abort\(|sys\.exi
CfgEntry = FunctionCfg | Sequence[FunctionCfg] | None
@dataclass(frozen=True)
class DominanceEvidence:
"""The strict dominance answer for prover mode: a relation, the guard's failure effect, and a reason when unknown."""
relation: EvidenceRelation
guard_effect: str | None = None
reason: str | None = None
class CfgDominance:
"""Dominance over control-flow graphs keyed by (path, function), with order as the recorded fallback."""
@@ -83,6 +94,36 @@ class CfgDominance:
return False
return cfg.effect(witness.line, operation.line, throwing=witness.kind in _THROWING) != "value_only"
def evidence(self, witness: Discharge, operation: Operation) -> DominanceEvidence:
"""Strict abstract relation (task 10.1): never falls back to order dominance.
Unavailable graphs, unmapped lines and cross-function witnesses return UNKNOWN with a
reason; the legacy boolean surface keeps its order fallback for non-opt-in callers.
"""
decided = _pre_graph_evidence(witness, operation)
if decided is not None:
return decided
guard_line = witness.line
if guard_line is None: # decided above; kept for line-type narrowing
return DominanceEvidence(EvidenceRelation.UNKNOWN, None, "dominance:no_line")
cfg = self.graph(operation.path, operation.function, operation.line)
if cfg is None:
return DominanceEvidence(EvidenceRelation.UNKNOWN, None, "cfg_unavailable")
found = cfg.relation(guard_line, operation.line)
if found is None:
return DominanceEvidence(EvidenceRelation.UNKNOWN, None, "line_without_node")
if found == "all_paths":
effect = cfg.effect(guard_line, operation.line, throwing=witness.kind in _THROWING)
if effect == "value_only":
return DominanceEvidence(EvidenceRelation.NO, effect)
return DominanceEvidence(EvidenceRelation.MUST, effect)
if found == "some_paths":
effect = cfg.effect(guard_line, operation.line, throwing=witness.kind in _THROWING)
return DominanceEvidence(EvidenceRelation.MAY, effect)
if found in ("none", "after"):
return DominanceEvidence(EvidenceRelation.NO, None)
return DominanceEvidence(EvidenceRelation.UNKNOWN, None, "dominance:unmapped_relation")
def relation(self, witness: Discharge, operation: Operation) -> str:
cfg = self._local(witness, operation)
found = cfg.relation(witness.line, operation.line) if cfg is not None and witness.line is not None else None
@@ -112,6 +153,23 @@ class CfgDominance:
return self.graph(operation.path, operation.function, operation.line)
def _pre_graph_evidence(witness: Discharge, operation: Operation) -> DominanceEvidence | None:
"""Relation facts that need no graph: scopes, in-operation kinds, cross-function witnesses, line order."""
if witness.scope in _SCOPED:
return DominanceEvidence(EvidenceRelation.MUST, "handler")
if witness.scope == "hop" or (witness.path, witness.function) != (operation.path, operation.function):
return DominanceEvidence(EvidenceRelation.UNKNOWN, None, "dominance:cross_function")
if witness.kind in _IN_OPERATION:
if witness.line == operation.line:
return DominanceEvidence(EvidenceRelation.MUST, "constrains")
return DominanceEvidence(EvidenceRelation.NO, "constrains")
if witness.line is None:
return DominanceEvidence(EvidenceRelation.UNKNOWN, None, "dominance:no_line")
if witness.line >= operation.line:
return DominanceEvidence(EvidenceRelation.NO, None)
return None
def describe(dominance: Dominance, witness: Discharge, operation: Operation, texts: Mapping[str, str]) -> tuple[str, str]:
"""A witness's relation to an operation and its failure effect, from the graph when the dominance has one."""
relation = getattr(dominance, "relation", None)
@@ -154,4 +212,4 @@ def _order_effect(texts: Mapping[str, str], witness: Discharge, operation: Opera
return "value_only"
__all__ = ["CfgDominance", "describe", "operation_context"]
__all__ = ["CfgDominance", "DominanceEvidence", "describe", "operation_context"]
+189
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@@ -0,0 +1,189 @@
"""Strict abstract-dominance relations over the CFG (Task 10.1, Reqs 10.1-10.7)."""
import pytest
from openultrasast.semantic.cfg import FunctionCfg
from openultrasast.semantic.cst import parse_function_nodes
from openultrasast.semantic.extra import grammar_for
from openultrasast.semantic.obligations.abstract_domain import EvidenceRelation
from openultrasast.semantic.obligations.cfg_dominance import CfgDominance, DominanceEvidence
from openultrasast.semantic.obligations.operations import Discharge, Operation
PATH = "src/C.java"
JAVA_GUARD = """class C {
void handle(Request request) {
if (!request.user.isAdmin()) { throw new IllegalStateException(); }
request.store.deleteAll();
}
}
"""
JAVA_VALUE_ONLY = """class C {
void handle(Request request) {
boolean admin = request.user.isAdmin();
request.store.deleteAll();
}
}
"""
JAVA_AFTER = """class C {
void handle(Request request) {
request.store.deleteAll();
if (!request.user.isAdmin()) { throw new IllegalStateException(); }
}
}
"""
JAVA_SOME_PATHS = """class C {
void handle(Request request) {
if (request.flag) {
if (!request.user.isAdmin()) { throw new IllegalStateException(); }
}
request.store.deleteAll();
}
}
"""
def _witness(line: int | None, *, kind: str = "path_guard", scope: str = "statement") -> Discharge:
return Discharge(
path=PATH,
line=line,
function="handle",
kind=kind,
fact_id="f:guard",
provenance="call",
scope=scope,
detail="",
)
def _operation(line: int) -> Operation:
return Operation(
path=PATH,
line=line,
function="handle",
kind="protected_read",
fact_id="f:op",
resource="store",
requires=("path_guard",),
)
def _dominance(text: str) -> CfgDominance:
if grammar_for("java") is None:
pytest.skip("no Java grammar installed")
nodes = parse_function_nodes(PATH, text, "java")
assert nodes, "the parser read no function"
cfg = FunctionCfg.from_cst(nodes[0], "java")
return CfgDominance({PATH: text}, {(PATH, "handle"): cfg})
def _lines(text: str) -> dict[str, int]:
file_lines = text.splitlines()
return {
"guard": next(number for number, line_text in enumerate(file_lines, start=1) if "isAdmin" in line_text),
"operation": next(number for number, line_text in enumerate(file_lines, start=1) if "deleteAll" in line_text),
}
def test_throwing_guard_on_all_paths_is_must() -> None:
dominance = _dominance(JAVA_GUARD)
lines = _lines(JAVA_GUARD)
evidence = dominance.evidence(_witness(lines["guard"]), _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.MUST
assert evidence.guard_effect == "throws"
def test_value_only_guard_on_all_paths_is_no() -> None:
dominance = _dominance(JAVA_VALUE_ONLY)
lines = _lines(JAVA_VALUE_ONLY)
evidence = dominance.evidence(_witness(lines["guard"], kind="ownership_check"), _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.NO
assert evidence.guard_effect == "value_only"
def test_guard_after_operation_is_no() -> None:
dominance = _dominance(JAVA_AFTER)
lines = _lines(JAVA_AFTER)
evidence = dominance.evidence(_witness(lines["guard"]), _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.NO
def test_branch_conditional_guard_is_may() -> None:
dominance = _dominance(JAVA_SOME_PATHS)
lines = _lines(JAVA_SOME_PATHS)
evidence = dominance.evidence(_witness(lines["guard"]), _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.MAY
def test_missing_graph_is_unknown_never_order_fallback() -> None:
dominance = CfgDominance({PATH: JAVA_GUARD}, {})
lines = _lines(JAVA_GUARD)
evidence = dominance.evidence(_witness(lines["guard"]), _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.UNKNOWN
assert evidence.reason == "cfg_unavailable"
def test_line_without_graph_node_is_unknown() -> None:
dominance = _dominance(JAVA_GUARD)
lines = _lines(JAVA_GUARD)
evidence = dominance.evidence(_witness(1), _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.UNKNOWN
assert evidence.reason == "line_without_node"
def test_cross_function_witness_is_unknown_never_order() -> None:
dominance = _dominance(JAVA_GUARD)
lines = _lines(JAVA_GUARD)
cross_function_witness = Discharge(
path=PATH,
line=lines["guard"],
function="other",
kind="path_guard",
fact_id="f:guard",
provenance="call",
scope="hop",
detail="",
)
evidence = dominance.evidence(cross_function_witness, _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.UNKNOWN
assert evidence.reason == "dominance:cross_function"
def test_scoped_witness_dominates_whole_handler() -> None:
dominance = _dominance(JAVA_GUARD)
lines = _lines(JAVA_GUARD)
scoped = _witness(None, scope="router")
evidence = dominance.evidence(scoped, _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.MUST
def test_in_operation_witness_same_line_is_must() -> None:
dominance = _dominance(JAVA_GUARD)
lines = _lines(JAVA_GUARD)
constraint = _witness(lines["operation"], kind="identity_constraint")
evidence = dominance.evidence(constraint, _operation(lines["operation"]))
assert evidence.relation is EvidenceRelation.MUST
def test_legacy_boolean_surface_unchanged() -> None:
dominance = CfgDominance({PATH: JAVA_GUARD}, {})
lines = _lines(JAVA_GUARD)
assert dominance.dominates(_witness(lines["guard"]), _operation(lines["operation"]), ()) is True
assert isinstance(dominance.relation(_witness(lines["guard"]), _operation(lines["operation"])), str)
def test_dominance_evidence_is_frozen() -> None:
evidence = DominanceEvidence(relation=EvidenceRelation.MUST, guard_effect="throws", reason=None)
with pytest.raises(Exception): # noqa: B017 - frozen dataclass raises on assignment
evidence.relation = EvidenceRelation.NO # type: ignore[misc]
def test_evidence_is_deterministic() -> None:
dominance = _dominance(JAVA_GUARD)
lines = _lines(JAVA_GUARD)
first = dominance.evidence(_witness(lines["guard"]), _operation(lines["operation"]))
second = dominance.evidence(_witness(lines["guard"]), _operation(lines["operation"]))
assert first == second