| // Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| library googleapis_auth.pem; |
| |
| import 'dart:convert'; |
| import 'dart:typed_data'; |
| |
| import 'asn1.dart'; |
| import 'rsa.dart'; |
| |
| /// Decode a [RSAPrivateKey] from the string content of a PEM file. |
| /// |
| /// A PEM file can be extracted from a .p12 cryptostore with |
| /// $ openssl pkcs12 -nocerts -nodes -passin pass:notasecret \ |
| /// -in *-privatekey.p12 -out *-privatekey.pem |
| RSAPrivateKey keyFromString(String pemFileString) { |
| if (pemFileString == null) { |
| throw new ArgumentError('Argument must not be null.'); |
| } |
| var bytes = _getBytesFromPEMString(pemFileString); |
| return _extractRSAKeyFromDERBytes(bytes); |
| } |
| |
| /// Helper function for decoding the base64 in [pemString]. |
| Uint8List _getBytesFromPEMString(String pemString) { |
| var lines = LineSplitter.split(pemString) |
| .map((line) => line.trim()) |
| .where((line) => line.isNotEmpty) |
| .toList(); |
| |
| if (lines.length < 2 || |
| !lines.first.startsWith('-----BEGIN') || |
| !lines.last.startsWith('-----END')) { |
| throw new ArgumentError('The given string does not have the correct ' |
| 'begin/end markers expected in a PEM file.'); |
| } |
| var base64 = lines.sublist(1, lines.length - 1).join(''); |
| return new Uint8List.fromList(base64Decode(base64)); |
| } |
| |
| /// Helper to decode the ASN.1/DER bytes in [bytes] into an [RSAPrivateKey]. |
| RSAPrivateKey _extractRSAKeyFromDERBytes(Uint8List bytes) { |
| // We recognize two formats: |
| // Real format: |
| // |
| // PrivateKey := seq[int/version=0, int/n, int/e, int/d, int/p, |
| // int/q, int/dmp1, int/dmq1, int/coeff] |
| // |
| // Or the above `PrivateKey` embeddded inside another ASN object: |
| // Encapsulated := seq[int/version=0, |
| // seq[obj-id/rsa-id, null-obj], |
| // octet-string/PrivateKey] |
| // |
| |
| RSAPrivateKey privateKeyFromSequence(ASN1Sequence asnSequence) { |
| var objects = asnSequence.objects; |
| |
| var asnIntegers = objects.take(9).map((o) => o as ASN1Integer).toList(); |
| |
| var version = asnIntegers.first; |
| if (version.integer != BigInt.zero) { |
| throw new ArgumentError('Expected version 0, got: ${version.integer}.'); |
| } |
| |
| var key = new RSAPrivateKey( |
| asnIntegers[1].integer, |
| asnIntegers[2].integer, |
| asnIntegers[3].integer, |
| asnIntegers[4].integer, |
| asnIntegers[5].integer, |
| asnIntegers[6].integer, |
| asnIntegers[7].integer, |
| asnIntegers[8].integer); |
| |
| var bitLength = key.bitLength; |
| if (bitLength != 1024 && bitLength != 2048 && bitLength != 4096) { |
| throw new ArgumentError('The RSA modulus has a bit length of $bitLength. ' |
| 'Only 1024, 2048 and 4096 are supported.'); |
| } |
| return key; |
| } |
| |
| try { |
| var asn = ASN1Parser.parse(bytes); |
| if (asn is ASN1Sequence) { |
| var objects = asn.objects; |
| if (objects.length == 3 && objects[2] is ASN1OctetString) { |
| ASN1OctetString string = objects[2]; |
| // Seems like the embedded form. |
| // TODO: Validate that rsa identifier matches! |
| return privateKeyFromSequence(ASN1Parser.parse(string.bytes)); |
| } |
| } |
| return privateKeyFromSequence(asn); |
| } catch (error) { |
| throw new ArgumentError( |
| 'Error while extracting private key from DER bytes: $error'); |
| } |
| } |
| |
| /* |
| * Example of generating a public/private RSA keypair with 2048 bits and dumping |
| * the structure of the resulting private key. |
| |
| $ openssl genrsa -out key.pem 2048 |
| Generating RSA private key, 2048 bit long modulus |
| ..................................................+++ |
| ..................................................+++ |
| e is 65537 (0x10001) |
| |
| $ cat key.pem |
| -----BEGIN RSA PRIVATE KEY----- |
| MIIEowIBAAKCAQEAuDOwXO14ltE1j2O0iDSuqtbw/1kMKjeiki3oehk2zNoUte42 |
| /s2rX15nYCkKtYG/r8WYvKzb31P4Uow1S4fFydKNWxgX4VtEjHgeqfPxeCL9wiJc |
| 9KkEt4fyhj1Jo7193gCLtovLAFwPzAMbFLiXWkfqalJ5Z77fOE4Mo7u4pEgxNPgL |
| VFGe0cEOAsHsKlsze+m1pmPHwWNVTcoKe5o0hOzy6hCPgVc6me6Y7aO8Fb4OVg0l |
| XQdQpWn2ikVBpzBcZ6InnYyJ/CJNa3WL1LJ65mmYnfHtKGoMqhLK48OReguwRwwF |
| e9/2+8UcdZcN5rsvt7yg3ZrKNH8rx+wZ36sRewIDAQABAoIBAQCn1HCcOsHkqDlk |
| rDOQ5m8+uRhbj4bF8GrvRWTL2q1TeF/mY2U4Q6wg+KK3uq1HMzCzthWz0suCb7+R |
| dq4YY1ySxoSEuy8G5WFPmyJVNy6Lh1Yty6FmSZlCn1sZdD3kMoK8A0NIz5Xmffrm |
| pu3Fs2ozl9K9jOeQ3xgC9RoPFLrm8lHJ45Vn+SnTxZnsXT6pwpg3TnFIx5ZinU8k |
| l0Um1n80qD2QQDakQ5jyr2odAELLBDlyCkxAglBXAVt4nk9Kl6nxb4snd9dnrL70 |
| WjLynWQsDczaV9TZIl2hYkMud+9OLVlUUtB+0c5b0p2t2P0sLltDaq3H6pT6yu2G |
| 8E86J9IBAoGBAPJaTNV5ysVOFn+YwWwRztzrvNArUJkVq8abN0gGp3gUvDEZnvzK |
| weF7+lfZzcwVRmQkL3mWLzzZvCx77RfulAzLi5iFuRBPhhhxAPDiDuyL9B7O81G/ |
| M/W5DPctGOyD/9cnLuh72oij0unc5MLSfzJf8wblpcjJnPBDqIVh6Qt9AoGBAMKT |
| Gacf4iSj1xW+0wrnbZlDuyCl6Msptj8ePcvLQrFqQmBwsXmWgVR+gFc/1G3lRft0 |
| QC6chsmafQHIIPpaDjq3sQ01/tUu7LXL+g/Hw9XtUHbkg3sZIQBtC26rKdStfHNS |
| KTvuCgn/dAJNjiohfhWMt9R4Q6E5FV6PqQHJzPJXAoGAC41qZDKuC8GxKNvrPG+M |
| 4NML6RBngySZT5pOhExs5zh10BFclshDfbAfOtjTCotpE5T1/mG+VrQ6WBSANMfW |
| ntWFDfwx2ikwRzH7zX+5HmV9eYp75sWqgGgVyiKIMZ4JMARaJBLjU+gbQbKZ5P+L |
| uKcCOq3vvSZ/KKTQ/6qvJTECgYBiWgbCgoxF5wdmd4Gn5llw+lqRYyur3hbACuJD |
| rCe3FDYfF3euNRSEiDkJYTtYnWbldtqmdPpw14VOrEF3KqQ8q/Nz8RIx4jlGn6dz |
| 6I8mCIH+xv1q8MXMuFHqC9zmIxdgF2y+XVF3wkd6jodI5oscC3g0juHokbkqhkVw |
| oPfWmwKBgBfR6jv0gWWeWTfkNwj+cMLHQV1uvz6JyLH5K4iISEDFxYkd37jrHB8A |
| 9hz9UDfmCbSs2j8CXDg7zCayM6tfu4Vtx+8S5g3oN6sa1JXFY1Os7SoXhTfX9M+7 |
| QpYYDJZwkgZrVQoKMIdCs9xfyVhZERq945NYLekwE1t2W+tOVBgR |
| -----END RSA PRIVATE KEY----- |
| |
| $ openssl enc -d -base64 -in key.pem -out key.bin |
| |
| $ dumpasn1 key.bin |
| 0 1187: SEQUENCE { |
| 4 1: INTEGER 0 |
| 7 257: INTEGER |
| : 00 B8 33 B0 5C ED 78 96 D1 35 8F 63 B4 88 34 AE |
| : AA D6 F0 FF 59 0C 2A 37 A2 92 2D E8 7A 19 36 CC |
| : DA 14 B5 EE 36 FE CD AB 5F 5E 67 60 29 0A B5 81 |
| : BF AF C5 98 BC AC DB DF 53 F8 52 8C 35 4B 87 C5 |
| : C9 D2 8D 5B 18 17 E1 5B 44 8C 78 1E A9 F3 F1 78 |
| : 22 FD C2 22 5C F4 A9 04 B7 87 F2 86 3D 49 A3 BD |
| : 7D DE 00 8B B6 8B CB 00 5C 0F CC 03 1B 14 B8 97 |
| : 5A 47 EA 6A 52 79 67 BE DF 38 4E 0C A3 BB B8 A4 |
| : [ Another 129 bytes skipped ] |
| 268 3: INTEGER 65537 |
| 273 257: INTEGER |
| : 00 A7 D4 70 9C 3A C1 E4 A8 39 64 AC 33 90 E6 6F |
| : 3E B9 18 5B 8F 86 C5 F0 6A EF 45 64 CB DA AD 53 |
| : 78 5F E6 63 65 38 43 AC 20 F8 A2 B7 BA AD 47 33 |
| : 30 B3 B6 15 B3 D2 CB 82 6F BF 91 76 AE 18 63 5C |
| : 92 C6 84 84 BB 2F 06 E5 61 4F 9B 22 55 37 2E 8B |
| : 87 56 2D CB A1 66 49 99 42 9F 5B 19 74 3D E4 32 |
| : 82 BC 03 43 48 CF 95 E6 7D FA E6 A6 ED C5 B3 6A |
| : 33 97 D2 BD 8C E7 90 DF 18 02 F5 1A 0F 14 BA E6 |
| : [ Another 129 bytes skipped ] |
| 534 129: INTEGER |
| : 00 F2 5A 4C D5 79 CA C5 4E 16 7F 98 C1 6C 11 CE |
| : DC EB BC D0 2B 50 99 15 AB C6 9B 37 48 06 A7 78 |
| : 14 BC 31 19 9E FC CA C1 E1 7B FA 57 D9 CD CC 15 |
| : 46 64 24 2F 79 96 2F 3C D9 BC 2C 7B ED 17 EE 94 |
| : 0C CB 8B 98 85 B9 10 4F 86 18 71 00 F0 E2 0E EC |
| : 8B F4 1E CE F3 51 BF 33 F5 B9 0C F7 2D 18 EC 83 |
| : FF D7 27 2E E8 7B DA 88 A3 D2 E9 DC E4 C2 D2 7F |
| : 32 5F F3 06 E5 A5 C8 C9 9C F0 43 A8 85 61 E9 0B |
| : [ Another 1 bytes skipped ] |
| 666 129: INTEGER |
| : 00 C2 93 19 A7 1F E2 24 A3 D7 15 BE D3 0A E7 6D |
| : 99 43 BB 20 A5 E8 CB 29 B6 3F 1E 3D CB CB 42 B1 |
| : 6A 42 60 70 B1 79 96 81 54 7E 80 57 3F D4 6D E5 |
| : 45 FB 74 40 2E 9C 86 C9 9A 7D 01 C8 20 FA 5A 0E |
| : 3A B7 B1 0D 35 FE D5 2E EC B5 CB FA 0F C7 C3 D5 |
| : ED 50 76 E4 83 7B 19 21 00 6D 0B 6E AB 29 D4 AD |
| : 7C 73 52 29 3B EE 0A 09 FF 74 02 4D 8E 2A 21 7E |
| : 15 8C B7 D4 78 43 A1 39 15 5E 8F A9 01 C9 CC F2 |
| : [ Another 1 bytes skipped ] |
| 798 128: INTEGER |
| : 0B 8D 6A 64 32 AE 0B C1 B1 28 DB EB 3C 6F 8C E0 |
| : D3 0B E9 10 67 83 24 99 4F 9A 4E 84 4C 6C E7 38 |
| : 75 D0 11 5C 96 C8 43 7D B0 1F 3A D8 D3 0A 8B 69 |
| : 13 94 F5 FE 61 BE 56 B4 3A 58 14 80 34 C7 D6 9E |
| : D5 85 0D FC 31 DA 29 30 47 31 FB CD 7F B9 1E 65 |
| : 7D 79 8A 7B E6 C5 AA 80 68 15 CA 22 88 31 9E 09 |
| : 30 04 5A 24 12 E3 53 E8 1B 41 B2 99 E4 FF 8B B8 |
| : A7 02 3A AD EF BD 26 7F 28 A4 D0 FF AA AF 25 31 |
| 929 128: INTEGER |
| : 62 5A 06 C2 82 8C 45 E7 07 66 77 81 A7 E6 59 70 |
| : FA 5A 91 63 2B AB DE 16 C0 0A E2 43 AC 27 B7 14 |
| : 36 1F 17 77 AE 35 14 84 88 39 09 61 3B 58 9D 66 |
| : E5 76 DA A6 74 FA 70 D7 85 4E AC 41 77 2A A4 3C |
| : AB F3 73 F1 12 31 E2 39 46 9F A7 73 E8 8F 26 08 |
| : 81 FE C6 FD 6A F0 C5 CC B8 51 EA 0B DC E6 23 17 |
| : 60 17 6C BE 5D 51 77 C2 47 7A 8E 87 48 E6 8B 1C |
| : 0B 78 34 8E E1 E8 91 B9 2A 86 45 70 A0 F7 D6 9B |
| 1060 128: INTEGER |
| : 17 D1 EA 3B F4 81 65 9E 59 37 E4 37 08 FE 70 C2 |
| : C7 41 5D 6E BF 3E 89 C8 B1 F9 2B 88 88 48 40 C5 |
| : C5 89 1D DF B8 EB 1C 1F 00 F6 1C FD 50 37 E6 09 |
| : B4 AC DA 3F 02 5C 38 3B CC 26 B2 33 AB 5F BB 85 |
| : 6D C7 EF 12 E6 0D E8 37 AB 1A D4 95 C5 63 53 AC |
| : ED 2A 17 85 37 D7 F4 CF BB 42 96 18 0C 96 70 92 |
| : 06 6B 55 0A 0A 30 87 42 B3 DC 5F C9 58 59 11 1A |
| : BD E3 93 58 2D E9 30 13 5B 76 5B EB 4E 54 18 11 |
| : } |
| */ |
