diff --git a/attest/eventlog.go b/attest/eventlog.go index a3c4d7d..b041e27 100644 --- a/attest/eventlog.go +++ b/attest/eventlog.go @@ -444,9 +444,13 @@ func parseSpecIDEvent(b []byte) (*specIDEvent, error) { // TODO(ericchiang): Check errata? Or do we expect that to change in ways // we're okay with? - algs := make([]specAlgSize, header.NumAlgs) - if err := binary.Read(r, binary.LittleEndian, &algs); err != nil { - return nil, fmt.Errorf("reading algorithms: %v", err) + specAlg := specAlgSize{} + e := specIDEvent{} + for i := 0; i < int(header.NumAlgs); i++ { + if err := binary.Read(r, binary.LittleEndian, &specAlg); err != nil { + return nil, fmt.Errorf("reading algorithm: %v", err) + } + e.algs = append(e.algs, specAlg.ID) } var vendorInfoSize uint8 @@ -456,10 +460,6 @@ func parseSpecIDEvent(b []byte) (*specIDEvent, error) { if r.Len() != int(vendorInfoSize) { return nil, fmt.Errorf("reading vendor info, expected %d remaining bytes, got %d", vendorInfoSize, r.Len()) } - var e specIDEvent - for _, alg := range algs { - e.algs = append(e.algs, alg.ID) - } return &e, nil } diff --git a/attest/eventlog_test.go b/attest/eventlog_test.go index a6b4631..169aa60 100644 --- a/attest/eventlog_test.go +++ b/attest/eventlog_test.go @@ -148,3 +148,111 @@ func TestParseEventLogEventSizeTooLarge(t *testing.T) { t.Fatalf("expected parsing invalid event log to fail") } } + +func TestParseSpecIDEvent(t *testing.T) { + tests := []struct { + name string + data []byte + want []uint16 + wantErr bool + }{ + { + name: "sha1", + data: append( + []byte("Spec ID Event03"), 0x0, + 0x0, 0x0, 0x0, 0x0, // platform class + 0x0, // verison minor + 0x2, // version major + 0x0, // errata + 0x8, // uintn size + 0x1, 0x0, 0x0, 0x0, // num algs + 0x04, 0x0, // SHA1 + 0x14, 0x0, // size + 0x2, // vendor info size + 0x0, 0x0, + ), + want: []uint16{0x0004}, + }, + { + name: "sha1_and_sha256", + data: append( + []byte("Spec ID Event03"), 0x0, + 0x0, 0x0, 0x0, 0x0, // platform class + 0x0, // verison minor + 0x2, // version major + 0x0, // errata + 0x8, // uintn size + 0x2, 0x0, 0x0, 0x0, // num algs + 0x04, 0x0, // SHA1 + 0x14, 0x0, // size + 0x0B, 0x0, // SHA256 + 0x20, 0x0, // size + 0x2, // vendor info size + 0x0, 0x0, + ), + want: []uint16{0x0004, 0x000B}, + }, + { + name: "invalid_version", + data: append( + []byte("Spec ID Event03"), 0x0, + 0x0, 0x0, 0x0, 0x0, // platform class + 0x2, // verison minor + 0x1, // version major + 0x0, // errata + 0x8, // uintn size + 0x2, 0x0, 0x0, 0x0, // num algs + 0x04, 0x0, // SHA1 + 0x14, 0x0, // size + 0x0B, 0x0, // SHA256 + 0x20, 0x0, // size + 0x2, // vendor info size + 0x0, 0x0, + ), + wantErr: true, + }, + { + name: "malicious_number_of_algs", + data: append( + []byte("Spec ID Event03"), 0x0, + 0x0, 0x0, 0x0, 0x0, // platform class + 0x0, // verison minor + 0x2, // version major + 0x0, // errata + 0x8, // uintn size + 0xff, 0xff, 0xff, 0xff, // num algs + 0x04, 0x0, // SHA1 + 0x14, 0x0, // size + 0x2, // vendor info size + 0x0, 0x0, + ), + wantErr: true, + }, + } + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + spec, err := parseSpecIDEvent(test.data) + if (err != nil) != test.wantErr { + t.Fatalf("parsing spec, wantErr=%t, got=%v", test.wantErr, err) + } + if err != nil { + return + } + algsEq := func(got, want []uint16) bool { + if len(got) != len(want) { + return false + } + for i, alg := range got { + if want[i] != alg { + return false + } + } + return true + } + + if !algsEq(test.want, spec.algs) { + t.Errorf("algorithms, got=%x, want=%x", spec.algs, test.want) + } + }) + } +}