| // Copyright 2025 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "components/trusted_vault/recovery_key_store_certificate.h" |
| |
| #include <string> |
| #include <string_view> |
| #include <vector> |
| |
| #include "base/base64.h" |
| #include "base/containers/span.h" |
| #include "base/memory/scoped_refptr.h" |
| #include "base/notimplemented.h" |
| #include "components/trusted_vault/securebox.h" |
| #include "crypto/signature_verifier.h" |
| #include "net/cert/asn1_util.h" |
| #include "net/cert/time_conversions.h" |
| #include "net/cert/x509_certificate.h" |
| #include "net/cert/x509_util.h" |
| #include "third_party/boringssl/src/pki/cert_issuer_source_static.h" |
| #include "third_party/boringssl/src/pki/parse_certificate.h" |
| #include "third_party/boringssl/src/pki/parsed_certificate.h" |
| #include "third_party/boringssl/src/pki/path_builder.h" |
| #include "third_party/boringssl/src/pki/simple_path_builder_delegate.h" |
| #include "third_party/boringssl/src/pki/trust_store_in_memory.h" |
| #include "third_party/libxml/chromium/xml_reader.h" |
| |
| namespace trusted_vault { |
| |
| namespace { |
| |
| // This is the root of trust for the backend certificate list verification. This |
| // is generated by the trusted execution platforms team |
| // (trusted-execution-platforms@google.com) and hardcoded in the server code |
| // that uses this cert in the google3 codebase. As a root CA cert, it should |
| // very rarely be changed. |
| constexpr uint8_t kRecoverableKeyStoreServiceRootCaCert[] = { |
| 0x30, 0x82, 0x05, 0x0f, 0x30, 0x82, 0x02, 0xf7, 0xa0, 0x03, 0x02, 0x01, |
| 0x02, 0x02, 0x10, 0x6c, 0xd7, 0x6e, 0x79, 0x4d, 0xa8, 0xd2, 0xf3, 0x3d, |
| 0x80, 0x6a, 0xb8, 0x37, 0xa6, 0xe1, 0x8f, 0x30, 0x0d, 0x06, 0x09, 0x2a, |
| 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x0b, 0x05, 0x00, 0x30, 0x31, |
| 0x31, 0x2f, 0x30, 0x2d, 0x06, 0x03, 0x55, 0x04, 0x03, 0x13, 0x26, 0x47, |
| 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x20, 0x43, 0x6c, 0x6f, 0x75, 0x64, 0x20, |
| 0x4b, 0x65, 0x79, 0x20, 0x56, 0x61, 0x75, 0x6c, 0x74, 0x20, 0x53, 0x65, |
| 0x72, 0x76, 0x69, 0x63, 0x65, 0x20, 0x52, 0x6f, 0x6f, 0x74, 0x20, 0x43, |
| 0x41, 0x30, 0x1e, 0x17, 0x0d, 0x31, 0x38, 0x30, 0x35, 0x30, 0x37, 0x31, |
| 0x38, 0x32, 0x34, 0x30, 0x32, 0x5a, 0x17, 0x0d, 0x33, 0x38, 0x30, 0x35, |
| 0x30, 0x38, 0x31, 0x39, 0x32, 0x34, 0x30, 0x32, 0x5a, 0x30, 0x31, 0x31, |
| 0x2f, 0x30, 0x2d, 0x06, 0x03, 0x55, 0x04, 0x03, 0x13, 0x26, 0x47, 0x6f, |
| 0x6f, 0x67, 0x6c, 0x65, 0x20, 0x43, 0x6c, 0x6f, 0x75, 0x64, 0x20, 0x4b, |
| 0x65, 0x79, 0x20, 0x56, 0x61, 0x75, 0x6c, 0x74, 0x20, 0x53, 0x65, 0x72, |
| 0x76, 0x69, 0x63, 0x65, 0x20, 0x52, 0x6f, 0x6f, 0x74, 0x20, 0x43, 0x41, |
| 0x30, 0x82, 0x02, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, |
| 0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x02, 0x0f, 0x00, |
| 0x30, 0x82, 0x02, 0x0a, 0x02, 0x82, 0x02, 0x01, 0x00, 0xad, 0x48, 0x33, |
| 0xbb, 0xee, 0x28, 0xf7, 0x29, 0x76, 0xd9, 0xea, 0xa5, 0xd4, 0x18, 0x86, |
| 0x06, 0xad, 0xe0, 0x59, 0x7a, 0x28, 0x87, 0x6a, 0xa5, 0xdc, 0x9f, 0xaf, |
| 0x56, 0xec, 0xdf, 0xfd, 0x38, 0x63, 0xcd, 0xd2, 0x20, 0xd3, 0x19, 0x24, |
| 0x93, 0x0f, 0xcd, 0x00, 0x5c, 0x58, 0x16, 0x2e, 0x3d, 0x12, 0x8d, 0x5f, |
| 0x6b, 0xf8, 0x5f, 0xf3, 0x00, 0x88, 0xa0, 0x0a, 0x82, 0x12, 0xcd, 0x65, |
| 0x0f, 0xab, 0x44, 0xdd, 0xc0, 0x83, 0xdd, 0x3d, 0xfe, 0x11, 0x03, 0xea, |
| 0xba, 0x1e, 0x82, 0x07, 0x62, 0xa6, 0x64, 0x32, 0x7a, 0x98, 0xf9, 0xd7, |
| 0xbd, 0x55, 0x25, 0x52, 0xe1, 0x6b, 0xd0, 0xed, 0x8c, 0xc1, 0x99, 0x30, |
| 0xca, 0x5a, 0x81, 0x11, 0x3c, 0xca, 0xd3, 0x1e, 0x4d, 0x08, 0x78, 0x0b, |
| 0xfe, 0x9e, 0x3b, 0xbe, 0x48, 0xe1, 0x1f, 0x1e, 0x8b, 0xa9, 0x56, 0xa8, |
| 0x6e, 0x28, 0x0a, 0x94, 0x7c, 0x6c, 0xce, 0xf5, 0x62, 0xe1, 0xf9, 0x2d, |
| 0xfe, 0xaa, 0xbb, 0x29, 0x6d, 0xd8, 0x4d, 0x5c, 0x61, 0xc1, 0xd2, 0xc6, |
| 0x11, 0xa6, 0xfe, 0x3a, 0xa4, 0x9f, 0xc0, 0xcc, 0x5d, 0x04, 0xb8, 0x4c, |
| 0x7c, 0x4d, 0x0a, 0xd1, 0xdb, 0xc5, 0xb7, 0xc6, 0xec, 0xf3, 0x22, 0x40, |
| 0x17, 0x4e, 0x03, 0x26, 0xc3, 0x1b, 0x44, 0x28, 0x45, 0x14, 0x1a, 0x53, |
| 0xd7, 0xb6, 0x74, 0xbb, 0x9d, 0xe2, 0x20, 0x00, 0x2e, 0xe6, 0xa5, 0x50, |
| 0x84, 0xaa, 0xd0, 0x5e, 0x22, 0x00, 0xc2, 0x06, 0xe8, 0x66, 0xa7, 0x7e, |
| 0x26, 0x41, 0xcb, 0x5d, 0x4d, 0x5f, 0x25, 0xe5, 0x53, 0xe5, 0x62, 0x4e, |
| 0x26, 0x0a, 0x09, 0x15, 0x61, 0xe4, 0x75, 0x69, 0x07, 0xb5, 0xae, 0x26, |
| 0x49, 0x89, 0x52, 0xef, 0x62, 0x75, 0x43, 0xdd, 0xbb, 0x24, 0x3d, 0x49, |
| 0x74, 0x44, 0xf5, 0x90, 0x5b, 0x47, 0xf8, 0x40, 0xed, 0x60, 0x0b, 0x71, |
| 0xef, 0x1e, 0xc5, 0xf7, 0x10, 0x00, 0x6d, 0xbd, 0xad, 0x30, 0x84, 0xf0, |
| 0xb3, 0xfc, 0x30, 0x77, 0x6a, 0xc0, 0xcd, 0x94, 0xd7, 0xfe, 0x4c, 0x51, |
| 0x6c, 0x39, 0x57, 0x54, 0xb4, 0xe8, 0x53, 0x4e, 0x4b, 0x15, 0x83, 0xeb, |
| 0xf9, 0xd1, 0x55, 0xd7, 0x0b, 0xd7, 0x9a, 0x2d, 0x23, 0x96, 0x42, 0x31, |
| 0x9e, 0x17, 0x5a, 0x54, 0x1a, 0x96, 0x0b, 0xdd, 0xe9, 0xe7, 0x6f, 0x14, |
| 0x89, 0x47, 0x0b, 0xa6, 0x26, 0xfe, 0x1d, 0x5c, 0xcc, 0x58, 0x67, 0x58, |
| 0x23, 0x71, 0xb5, 0x34, 0xe6, 0xbf, 0x95, 0x3a, 0x74, 0x73, 0xc2, 0xdc, |
| 0x6c, 0x98, 0xda, 0xa6, 0x28, 0x95, 0x9d, 0xe4, 0x50, 0x27, 0x77, 0x08, |
| 0xa8, 0x33, 0xce, 0x48, 0x49, 0xc4, 0xab, 0x8d, 0x21, 0xc9, 0x97, 0x75, |
| 0x8f, 0x1d, 0xc9, 0x9c, 0xec, 0x49, 0x33, 0x01, 0xec, 0xf2, 0xfe, 0x2c, |
| 0xf4, 0x62, 0x25, 0x6f, 0x70, 0x5c, 0x3a, 0x60, 0xef, 0x03, 0xf3, 0x2e, |
| 0xd3, 0xdc, 0x44, 0x30, 0xac, 0x29, 0x1c, 0x19, 0xb8, 0x4c, 0x50, 0xca, |
| 0x5d, 0xe1, 0x87, 0x39, 0x68, 0x5a, 0xed, 0xc7, 0x16, 0x10, 0x40, 0x9b, |
| 0xc8, 0xee, 0x67, 0x72, 0xee, 0x97, 0xb8, 0xdd, 0xa2, 0xcb, 0x3f, 0x52, |
| 0xf9, 0x3b, 0x8c, 0xca, 0x36, 0x41, 0x13, 0x9e, 0x76, 0xa7, 0xa3, 0xee, |
| 0xe6, 0x01, 0x02, 0xdb, 0x19, 0x3e, 0xa9, 0xa6, 0xf4, 0x34, 0x60, 0xd3, |
| 0x1d, 0xd2, 0xca, 0x2d, 0xbc, 0x96, 0x9f, 0x72, 0x31, 0x76, 0x60, 0x47, |
| 0xc9, 0x3a, 0xfb, 0x88, 0xf0, 0xaa, 0x9a, 0x9c, 0x87, 0x9e, 0x09, 0x02, |
| 0xfe, 0x96, 0xc6, 0x7e, 0xf1, 0xae, 0xb1, 0xce, 0x41, 0xa4, 0x1b, 0xa0, |
| 0xb0, 0x1b, 0x65, 0xcf, 0xae, 0xe6, 0xe1, 0x15, 0x8b, 0x27, 0xbd, 0xb2, |
| 0x01, 0xe5, 0x4f, 0x3b, 0xf9, 0x72, 0xff, 0xcc, 0x38, 0xa2, 0xb3, 0x6c, |
| 0x19, 0x68, 0xe7, 0xde, 0xcd, 0x02, 0x03, 0x01, 0x00, 0x01, 0xa3, 0x23, |
| 0x30, 0x21, 0x30, 0x0e, 0x06, 0x03, 0x55, 0x1d, 0x0f, 0x01, 0x01, 0xff, |
| 0x04, 0x04, 0x03, 0x02, 0x01, 0x86, 0x30, 0x0f, 0x06, 0x03, 0x55, 0x1d, |
| 0x13, 0x01, 0x01, 0xff, 0x04, 0x05, 0x30, 0x03, 0x01, 0x01, 0xff, 0x30, |
| 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x0b, |
| 0x05, 0x00, 0x03, 0x82, 0x02, 0x01, 0x00, 0x68, 0x96, 0x96, 0xef, 0xb8, |
| 0xab, 0x2c, 0x60, 0x3d, 0xbe, 0x91, 0xb0, 0x0d, 0x26, 0xc1, 0x1e, 0xd5, |
| 0xdb, 0x55, 0x09, 0xf6, 0xb1, 0x29, 0x62, 0x14, 0x8d, 0xf8, 0x04, 0x69, |
| 0x4d, 0x61, 0xa2, 0x23, 0x6d, 0x91, 0x08, 0x94, 0x86, 0x2b, 0x46, 0x6b, |
| 0x3c, 0x67, 0x85, 0x43, 0x31, 0x36, 0x06, 0x99, 0xd5, 0x45, 0xd9, 0x8b, |
| 0x4d, 0x5e, 0x63, 0x7f, 0xd2, 0x54, 0x4a, 0xd8, 0xc7, 0xa0, 0xfb, 0xcd, |
| 0x60, 0x59, 0xf0, 0x2d, 0x32, 0x74, 0x13, 0x67, 0xbd, 0x3a, 0x58, 0xfc, |
| 0x32, 0xb1, 0xeb, 0x02, 0xe7, 0x00, 0x50, 0x52, 0xe1, 0x97, 0x8c, 0x28, |
| 0x5b, 0x3d, 0x24, 0x53, 0xf5, 0xf4, 0x10, 0x1d, 0x63, 0xe9, 0x8d, 0x92, |
| 0x5e, 0xb0, 0x1a, 0x64, 0xf8, 0x8c, 0x32, 0x9a, 0xbc, 0x04, 0xa8, 0xf7, |
| 0x98, 0x7d, 0x4c, 0x6d, 0x5e, 0x2c, 0xb5, 0x9d, 0x24, 0x88, 0x75, 0x29, |
| 0x66, 0xee, 0x8f, 0x12, 0x6a, 0xe8, 0x8d, 0x81, 0xbb, 0x14, 0xa2, 0x8d, |
| 0xdf, 0x49, 0xda, 0xdb, 0x15, 0xdf, 0x88, 0xe7, 0xe5, 0xd8, 0x9b, 0xac, |
| 0x56, 0xcc, 0x87, 0x0e, 0xa9, 0x94, 0x9f, 0xf1, 0xe3, 0x4e, 0x1e, 0xb3, |
| 0x01, 0x22, 0xaa, 0x13, 0xa8, 0x71, 0x13, 0xe1, 0x49, 0x46, 0x5d, 0x95, |
| 0x43, 0x87, 0x5c, 0xaf, 0x84, 0xaf, 0x88, 0x7b, 0x5d, 0x6e, 0x29, 0x8c, |
| 0xcb, 0x62, 0xe0, 0x84, 0xb9, 0xd9, 0xe0, 0x51, 0x38, 0x5e, 0x12, 0x60, |
| 0x46, 0x7c, 0x3d, 0x4d, 0xe4, 0x55, 0xe4, 0x2f, 0x52, 0x9f, 0xba, 0x66, |
| 0x9c, 0x00, 0x39, 0x5f, 0x40, 0xbc, 0x65, 0x78, 0x57, 0xbd, 0xfb, 0xeb, |
| 0x77, 0x1e, 0x1f, 0x2f, 0x75, 0x0a, 0x96, 0x4d, 0x4b, 0xaa, 0x56, 0xf9, |
| 0xb2, 0x4c, 0x68, 0x2b, 0x54, 0x7d, 0xc3, 0x0a, 0xfe, 0x68, 0xd2, 0x0e, |
| 0xf9, 0xcb, 0x91, 0xf0, 0x90, 0x39, 0x0e, 0x61, 0x03, 0x58, 0x5c, 0x39, |
| 0x06, 0xe7, 0x61, 0xfe, 0xe5, 0x96, 0x66, 0x50, 0x53, 0xc9, 0x55, 0xb6, |
| 0xc9, 0xb6, 0xd3, 0x07, 0xab, 0x64, 0x98, 0xe7, 0x3c, 0x73, 0x4f, 0x17, |
| 0x3a, 0x0c, 0x41, 0x68, 0xaa, 0xec, 0x5c, 0x02, 0xe6, 0x25, 0xc9, 0x6e, |
| 0x69, 0xb8, 0xe6, 0x37, 0x58, 0xe9, 0xf3, 0x56, 0x9e, 0xd5, 0xea, 0x5e, |
| 0x37, 0x7d, 0x63, 0x27, 0x83, 0x79, 0x20, 0x4e, 0x5a, 0xab, 0xb5, 0xdb, |
| 0x4c, 0x59, 0x8a, 0x93, 0x0a, 0x60, 0x4d, 0x3b, 0xc9, 0x9a, 0xa0, 0x91, |
| 0xd9, 0x7c, 0xd6, 0xba, 0x39, 0x6f, 0x75, 0xb7, 0x63, 0x7e, 0x20, 0x01, |
| 0x96, 0x25, 0xac, 0x9c, 0xbc, 0xcb, 0x40, 0x23, 0xfc, 0x79, 0x9c, 0x1c, |
| 0x33, 0x82, 0xc0, 0xe5, 0x42, 0xb7, 0x7f, 0x59, 0x2d, 0x1e, 0x89, 0x6b, |
| 0xd4, 0xe2, 0x3d, 0x7a, 0xd4, 0x8e, 0x91, 0xe6, 0xc4, 0xda, 0x9c, 0xbc, |
| 0x2c, 0xf6, 0x01, 0x25, 0x69, 0x57, 0xdf, 0xab, 0x51, 0x01, 0xa8, 0x19, |
| 0x85, 0x4f, 0xcd, 0xa3, 0x23, 0xad, 0xbe, 0x14, 0x73, 0xab, 0xda, 0xdb, |
| 0xde, 0xb6, 0xdf, 0xf7, 0xa0, 0x0f, 0x10, 0x72, 0x94, 0x16, 0xc5, 0xc6, |
| 0xf6, 0x70, 0x44, 0x77, 0x60, 0x54, 0x29, 0x98, 0x21, 0x2c, 0xa3, 0xdf, |
| 0xf8, 0x93, 0x42, 0x53, 0xfd, 0xa9, 0x38, 0x6c, 0x74, 0x8d, 0xd3, 0x1c, |
| 0x7f, 0xe2, 0xbe, 0x6b, 0x50, 0xde, 0x1b, 0x46, 0x33, 0x19, 0x83, 0x11, |
| 0x90, 0x5b, 0xe9, 0x37, 0x78, 0x6f, 0x1d, 0x8a, 0xc9, 0x74, 0x1c, 0x8b, |
| 0xde, 0x44, 0x8f, 0xdd, 0x4b, 0x43, 0xd0, 0x7d, 0xa0, 0xf0, 0xfb, 0x3b, |
| 0x81, 0x12, 0xc4, 0x2c, 0x6d, 0x87, 0x38, 0x3c, 0x5b, 0x4a, 0x7f, 0x0f, |
| 0x57, 0x75, 0xed, 0xb9, 0x2b, 0xf1, 0x55, 0xa9, 0xc0, 0xea, 0xec, 0x9a, |
| 0x69, 0x2d, 0xc0, 0x67, 0xa4, 0xb1, 0x79, 0x52, 0xef, 0x9b, 0x0e, 0x74, |
| 0xed, 0xa6, 0x08}; |
| |
| // Returns a list of certificates from a certificate tag, traversing its entire |
| // contents. Ignores anything that is not a <cert> tag directly below the |
| // certificate tag. |
| // |xml_reader| must be pointing at the opening element that wraps certificates. |
| // After processing, |xml_reader| will be pointing at the matching closing tag. |
| // <intermediates> <-- Point xml_reader here to start. |
| // <cert>cert1</cert> |
| // <not-cert>not a certificate</not-cert> <-- ignored |
| // <cert>cert2</cert> |
| // </intermediates> <-- xml_reader will point here after processing. |
| // In this case, the return value would be { cert1, cert2 }. |
| std::vector<std::string> ParseCertList(XmlReader* xml_reader) { |
| std::vector<std::string> cert_list; |
| const int starting_depth = xml_reader->Depth(); |
| while (xml_reader->Read() && xml_reader->Depth() > starting_depth) { |
| // Look for a <cert> element nested just under the starting tag. |
| if (!xml_reader->IsElement() || xml_reader->Depth() != starting_depth + 1 || |
| xml_reader->NodeName() != "cert") { |
| continue; |
| } |
| std::string cert; |
| if (!xml_reader->ReadElementContent(&cert) || cert.empty()) { |
| continue; |
| } |
| cert_list.push_back(std::move(cert)); |
| } |
| return cert_list; |
| } |
| |
| // Given a base64-encoded x509 certificate, returns the bssl representation (or |
| // nullptr if decoding failed). |
| std::shared_ptr<const bssl::ParsedCertificate> CertificateFromBase64( |
| std::string_view b64) { |
| std::optional<std::vector<uint8_t>> certificate_data = |
| base::Base64Decode(b64); |
| if (!certificate_data) { |
| return nullptr; |
| } |
| return bssl::ParsedCertificate::Create( |
| net::x509_util::CreateCryptoBuffer(*certificate_data), |
| net::x509_util::DefaultParseCertificateOptions(), /*errors=*/nullptr); |
| } |
| |
| // Returns a fresh trusted cert store for the cloud root. |
| std::unique_ptr<bssl::TrustStoreInMemory> ConstructTrustedCertStore() { |
| // This code will run at most once a day. So there's no point keeping the |
| // trust store around after use. |
| auto trust_store = std::make_unique<bssl::TrustStoreInMemory>(); |
| std::shared_ptr<const bssl::ParsedCertificate> root_cert = |
| bssl::ParsedCertificate::Create( |
| net::x509_util::CreateCryptoBuffer( |
| kRecoverableKeyStoreServiceRootCaCert), |
| net::x509_util::DefaultParseCertificateOptions(), /*errors=*/nullptr); |
| CHECK(root_cert); |
| trust_store->AddTrustAnchor(root_cert); |
| return trust_store; |
| } |
| |
| } // namespace |
| |
| namespace internal { |
| |
| ParsedRecoveryKeyStoreCertXML::ParsedRecoveryKeyStoreCertXML( |
| std::vector<std::string> intermediates, |
| std::vector<std::string> endpoints) |
| : intermediates(std::move(intermediates)), |
| endpoints(std::move(endpoints)) {} |
| |
| ParsedRecoveryKeyStoreCertXML::ParsedRecoveryKeyStoreCertXML( |
| ParsedRecoveryKeyStoreCertXML&&) = default; |
| ParsedRecoveryKeyStoreCertXML& ParsedRecoveryKeyStoreCertXML::operator=( |
| ParsedRecoveryKeyStoreCertXML&&) = default; |
| |
| ParsedRecoveryKeyStoreCertXML::~ParsedRecoveryKeyStoreCertXML() = default; |
| |
| ParsedRecoveryKeyStoreSigXML::ParsedRecoveryKeyStoreSigXML( |
| std::vector<std::string> intermediates, |
| std::string certificate, |
| std::string signature) |
| : intermediates(std::move(intermediates)), |
| certificate(std::move(certificate)), |
| signature(std::move(signature)) {} |
| |
| ParsedRecoveryKeyStoreSigXML::ParsedRecoveryKeyStoreSigXML( |
| ParsedRecoveryKeyStoreSigXML&&) = default; |
| ParsedRecoveryKeyStoreSigXML& ParsedRecoveryKeyStoreSigXML::operator=( |
| ParsedRecoveryKeyStoreSigXML&&) = default; |
| |
| ParsedRecoveryKeyStoreSigXML::~ParsedRecoveryKeyStoreSigXML() = default; |
| |
| std::optional<ParsedRecoveryKeyStoreCertXML> ParseRecoveryKeyStoreCertXML( |
| std::string_view cert_xml) { |
| XmlReader xml_reader; |
| xml_reader.Load(cert_xml); |
| if (!xml_reader.Read() || xml_reader.NodeName() != "certificate") { |
| return std::nullopt; |
| } |
| std::vector<std::string> intermediates; |
| std::vector<std::string> endpoints; |
| while (xml_reader.Read()) { |
| // Skip anything that is not an element nested under the root. |
| if (!xml_reader.IsElement() || xml_reader.Depth() != 1) { |
| continue; |
| } |
| // We expect a single <intermediates> and <endpoints> tags. This code only |
| // has the last tags take effect, but that should be okay. |
| if (xml_reader.NodeName() == "intermediates") { |
| intermediates = ParseCertList(&xml_reader); |
| } else if (xml_reader.NodeName() == "endpoints") { |
| endpoints = ParseCertList(&xml_reader); |
| } |
| } |
| if (intermediates.empty() || endpoints.empty()) { |
| return std::nullopt; |
| } |
| return ParsedRecoveryKeyStoreCertXML(std::move(intermediates), |
| std::move(endpoints)); |
| } |
| |
| std::optional<ParsedRecoveryKeyStoreSigXML> ParseRecoveryKeyStoreSigXML( |
| std::string_view sig_xml) { |
| XmlReader xml_reader; |
| xml_reader.Load(sig_xml); |
| if (!xml_reader.Read() || xml_reader.NodeName() != "signature") { |
| return std::nullopt; |
| } |
| std::vector<std::string> intermediates; |
| std::string certificate; |
| std::string signature; |
| while (xml_reader.Read()) { |
| // Skip anything that is not an element nested under the root. |
| if (!xml_reader.IsElement() || xml_reader.Depth() != 1) { |
| continue; |
| } |
| // We expect a single <intermediates>, <certificate>, and <value> tags. This |
| // code only has the last tags take effect, but that should be okay. |
| if (xml_reader.NodeName() == "intermediates") { |
| intermediates = ParseCertList(&xml_reader); |
| } else if (xml_reader.NodeName() == "certificate") { |
| if (!xml_reader.ReadElementContent(&certificate)) { |
| return std::nullopt; |
| } |
| } else if (xml_reader.NodeName() == "value") { |
| if (!xml_reader.ReadElementContent(&signature)) { |
| return std::nullopt; |
| } |
| } |
| } |
| if (intermediates.empty() || certificate.empty() || signature.empty()) { |
| return std::nullopt; |
| } |
| return ParsedRecoveryKeyStoreSigXML( |
| std::move(intermediates), std::move(certificate), std::move(signature)); |
| } |
| |
| std::shared_ptr<const bssl::ParsedCertificate> VerifySignatureChain( |
| std::string_view certificate_b64, |
| base::span<std::string> intermediates_b64, |
| base::Time current_time) { |
| std::shared_ptr<const bssl::ParsedCertificate> certificate = |
| CertificateFromBase64(certificate_b64); |
| if (!certificate) { |
| return nullptr; |
| } |
| |
| bssl::CertIssuerSourceStatic intermediates; |
| for (const auto& intermediate_b64 : intermediates_b64) { |
| std::shared_ptr<const bssl::ParsedCertificate> intermediate = |
| CertificateFromBase64(intermediate_b64); |
| if (!intermediate) { |
| // Ignore invalid base64. We may still be able to build a valid path. |
| continue; |
| } |
| intermediates.AddCert(std::move(intermediate)); |
| } |
| |
| std::unique_ptr<bssl::TrustStoreInMemory> trusted_cert_store = |
| ConstructTrustedCertStore(); |
| bssl::SimplePathBuilderDelegate builder_delegate( |
| /*min_rsa_modulus_length_bits=*/2048, |
| bssl::SimplePathBuilderDelegate::DigestPolicy::kStrong); |
| bssl::der::GeneralizedTime verification_time; |
| CHECK(net::EncodeTimeAsGeneralizedTime(current_time, &verification_time)); |
| bssl::CertPathBuilder path_builder(certificate, trusted_cert_store.get(), |
| &builder_delegate, verification_time, |
| bssl::KeyPurpose::ANY_EKU, |
| bssl::InitialExplicitPolicy::kFalse, |
| {bssl::der::Input(bssl::kAnyPolicyOid)}, |
| bssl::InitialPolicyMappingInhibit::kFalse, |
| bssl::InitialAnyPolicyInhibit::kFalse); |
| path_builder.AddCertIssuerSource(&intermediates); |
| bssl::CertPathBuilder::Result result = path_builder.Run(); |
| if (!result.HasValidPath()) { |
| return nullptr; |
| } |
| return certificate; |
| } |
| |
| bool VerifySignature(std::shared_ptr<const bssl::ParsedCertificate> certificate, |
| std::string_view cert_xml, |
| std::string_view signature_b64) { |
| std::optional<std::vector<uint8_t>> signature = |
| base::Base64Decode(signature_b64); |
| if (!signature) { |
| return false; |
| } |
| size_t size_bits; |
| net::X509Certificate::PublicKeyType type; |
| net::X509Certificate::GetPublicKeyInfo(certificate->cert_buffer(), &size_bits, |
| &type); |
| crypto::SignatureVerifier::SignatureAlgorithm algo; |
| switch (type) { |
| case net::X509Certificate::PublicKeyType::kPublicKeyTypeECDSA: |
| algo = crypto::SignatureVerifier::SignatureAlgorithm::ECDSA_SHA256; |
| break; |
| case net::X509Certificate::PublicKeyType::kPublicKeyTypeRSA: |
| algo = crypto::SignatureVerifier::SignatureAlgorithm::RSA_PKCS1_SHA256; |
| break; |
| case net::X509Certificate::PublicKeyType::kPublicKeyTypeUnknown: |
| return false; |
| } |
| crypto::SignatureVerifier signature_verifier; |
| if (!net::x509_util::SignatureVerifierInitWithCertificate( |
| &signature_verifier, algo, *signature, certificate->cert_buffer())) { |
| return false; |
| } |
| signature_verifier.VerifyUpdate(base::as_byte_span(cert_xml)); |
| return signature_verifier.VerifyFinal(); |
| } |
| |
| std::vector<std::unique_ptr<SecureBoxPublicKey>> ExtractEndpointPublicKeys( |
| ParsedRecoveryKeyStoreCertXML cert_xml, |
| base::Time current_time) { |
| std::vector<std::unique_ptr<SecureBoxPublicKey>> result; |
| for (const auto& endpoint : cert_xml.endpoints) { |
| std::shared_ptr<const bssl::ParsedCertificate> certificate = |
| VerifySignatureChain(endpoint, cert_xml.intermediates, current_time); |
| if (!certificate) { |
| continue; |
| } |
| // Only ECDSA public keys are supported. |
| size_t size_bits; |
| net::X509Certificate::PublicKeyType type; |
| net::X509Certificate::GetPublicKeyInfo(certificate->cert_buffer(), |
| &size_bits, &type); |
| if (type != net::X509Certificate::kPublicKeyTypeECDSA) { |
| continue; |
| } |
| // Extract the public key from the SPKI. |
| std::string_view ec_point_oct; |
| if (!net::asn1::ExtractSubjectPublicKeyFromSPKI( |
| certificate->tbs().spki_tlv.AsStringView(), &ec_point_oct)) { |
| continue; |
| } |
| // ExtractSubjectPublicKeyFromSPKI does not remove the initial octet |
| // encoding the number of unused bits in the ASN.1 BIT STRING so we do it |
| // here. The public key is always byte-aligned. |
| ec_point_oct.remove_prefix(1); |
| |
| std::unique_ptr<SecureBoxPublicKey> key = |
| SecureBoxPublicKey::CreateByImport(base::as_byte_span(ec_point_oct)); |
| if (!key) { |
| continue; |
| } |
| result.push_back(std::move(key)); |
| } |
| return result; |
| } |
| |
| } // namespace internal |
| |
| // static |
| std::optional<RecoveryKeyStoreCertificate> RecoveryKeyStoreCertificate::Parse( |
| std::string_view cert_xml, |
| std::string_view sig_xml, |
| base::Time current_time) { |
| std::optional<internal::ParsedRecoveryKeyStoreSigXML> parsed_sig_xml = |
| internal::ParseRecoveryKeyStoreSigXML(sig_xml); |
| if (!parsed_sig_xml) { |
| return std::nullopt; |
| } |
| std::shared_ptr<const bssl::ParsedCertificate> signing_certificate = |
| internal::VerifySignatureChain(std::move(parsed_sig_xml->certificate), |
| parsed_sig_xml->intermediates, |
| current_time); |
| if (!signing_certificate || !signing_certificate->has_key_usage() || |
| !signing_certificate->key_usage().AssertsBit( |
| bssl::KEY_USAGE_BIT_DIGITAL_SIGNATURE)) { |
| return std::nullopt; |
| } |
| if (!internal::VerifySignature(std::move(signing_certificate), cert_xml, |
| parsed_sig_xml->signature)) { |
| return std::nullopt; |
| } |
| std::optional<internal::ParsedRecoveryKeyStoreCertXML> parsed_cert_xml = |
| internal::ParseRecoveryKeyStoreCertXML(cert_xml); |
| if (!parsed_cert_xml) { |
| return std::nullopt; |
| } |
| std::vector<std::unique_ptr<SecureBoxPublicKey>> endpoint_public_keys = |
| internal::ExtractEndpointPublicKeys(std::move(*parsed_cert_xml), |
| current_time); |
| if (endpoint_public_keys.empty()) { |
| return std::nullopt; |
| } |
| return RecoveryKeyStoreCertificate(std::move(endpoint_public_keys)); |
| } |
| |
| RecoveryKeyStoreCertificate::RecoveryKeyStoreCertificate( |
| RecoveryKeyStoreCertificate&& other) = default; |
| RecoveryKeyStoreCertificate& RecoveryKeyStoreCertificate::operator=( |
| RecoveryKeyStoreCertificate&& other) = default; |
| RecoveryKeyStoreCertificate::~RecoveryKeyStoreCertificate() = default; |
| |
| RecoveryKeyStoreCertificate::RecoveryKeyStoreCertificate( |
| std::vector<std::unique_ptr<SecureBoxPublicKey>> endpoint_public_keys) |
| : endpoint_public_keys_(std::move(endpoint_public_keys)) {} |
| |
| } // namespace trusted_vault |
