diff options
| -rw-r--r-- | crypto/src/security/JksStore.cs | 144 | ||||
| -rw-r--r-- | crypto/test/data/jks/cacerts.jks | bin | 0 -> 156996 bytes | |||
| -rw-r--r-- | crypto/test/src/security/test/JksStoreTest.cs | 16 |
3 files changed, 141 insertions, 19 deletions
diff --git a/crypto/src/security/JksStore.cs b/crypto/src/security/JksStore.cs index 4df0b39db..a7d3f6ca3 100644 --- a/crypto/src/security/JksStore.cs +++ b/crypto/src/security/JksStore.cs @@ -726,20 +726,81 @@ namespace Org.BouncyCastle.Security private static string ReadUtf(BinaryReader br) { - byte[] utfBytes = ReadBufferWithInt16Length(br); + byte[] mUtfBytes = ReadBufferWithInt16Length(br); + + int i = 0; + MemoryStream utfBytes = new MemoryStream(mUtfBytes.Length); + + while (i < mUtfBytes.Length) + { + // Modified UTF-8 differs from regular UTF-8 in the following + // ways: + // + // 1. NULL bytes never occur in the stream and are always + // two-byte encoded. + // 2. There are no four-byte values and are instead always + // encoded using surrogate pairs. + // + // See also: https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/io/DataInput.html#modified-utf-8 + byte mUtfByte = mUtfBytes[i]; + if (mUtfByte == 0) + throw new NotSupportedException("Unexpected NULL byte in modified UTF-8 encoding in JKS"); + + if ((mUtfByte & 0x80) == 0) + { + // No transformation is applied to non-NULL ASCII bytes. + utfBytes.WriteByte(mUtfByte); + i += 1; + } + else if ((mUtfByte & 0xE0) == 0xC0) + { + // Validate we have another byte. + if ((i + 1) >= mUtfBytes.Length) + throw new NotSupportedException("Two-byte sentinel found at end of input stream"); - /* - * FIXME JKS actually uses a "modified UTF-8" format. For the moment we will just support single-byte - * encodings that aren't null bytes. - */ - for (int i = 0; i < utfBytes.Length; ++i) - { - byte utfByte = utfBytes[i]; - if (utfByte == 0 || (utfByte & 0x80) != 0) - throw new NotSupportedException("Currently missing support for modified UTF-8 encoding in JKS"); + byte mUtfByteSecond = mUtfBytes[i+1]; + if ((mUtfByteSecond & 0xC0) != 0x80) + throw new NotSupportedException("Second byte in two-byte modified UTF-8 encoding malformed"); + + // We might have encoded the NULL byte as two bytes. + if (mUtfByte == 0xC0 && mUtfByteSecond == 0x80) + { + utfBytes.WriteByte(0x00); + } else { + utfBytes.WriteByte(mUtfByte); + utfBytes.WriteByte(mUtfByteSecond); + } + + i += 2; + } + else if ((mUtfByte & 0xF0) == 0xE0) + { + // Validate we have enough bytes. + if ((i + 2) >= mUtfBytes.Length) + throw new NotSupportedException("Three-byte sentinel found at end of input stream"); + + byte mUtfByteSecond = mUtfBytes[i+1]; + if ((mUtfByteSecond & 0xC0) != 0x80) + throw new NotSupportedException("Second byte in two-byte modified UTF-8 encoding malformed"); + + byte mUtfByteThird = mUtfBytes[i+2]; + if ((mUtfByteThird & 0xC0) != 0x80) + throw new NotSupportedException("Third byte in two-byte modified UTF-8 encoding malformed"); + + utfBytes.WriteByte(mUtfByte); + utfBytes.WriteByte(mUtfByteSecond); + utfBytes.WriteByte(mUtfByteThird); + + i += 3; + } + else + { + // Reachable when we have a non-standard four-byte sentinel mask. + throw new NotSupportedException("Malformed modified UTF-8 encoding at index " + i); + } } - return Encoding.UTF8.GetString(utfBytes); + return Encoding.UTF8.GetString(utfBytes.ToArray()); } private static void WriteBufferWithInt16Length(BinaryWriter bw, byte[] buffer) @@ -770,18 +831,63 @@ namespace Org.BouncyCastle.Security { byte[] utfBytes = Encoding.UTF8.GetBytes(s); - /* - * FIXME JKS actually uses a "modified UTF-8" format. For the moment we will just support single-byte - * encodings that aren't null bytes. - */ - for (int i = 0; i < utfBytes.Length; ++i) + int i = 0; + MemoryStream mUtfBytes = new MemoryStream(); + while (i < utfBytes.Length) { byte utfByte = utfBytes[i]; - if (utfByte == 0 || (utfByte & 0x80) != 0) - throw new NotSupportedException("Currently missing support for modified UTF-8 encoding in JKS"); + if (utfByte == 0) + { + // The NULL byte is encoded in two byte format. + mUtfBytes.WriteByte(0xC0); + mUtfBytes.WriteByte(0x80); + i += 1; + } + else if ((utfByte & 0x80) == 0) + { + // One byte UTF-8 bytes are written directly. + mUtfBytes.WriteByte(utfByte); + i += 1; + } + else if ((utfByte & 0xE0) == 0xC0) + { + // Two byte UTF-8 values are preserved as-is. + if ((i + 1) >= utfBytes.Length) + throw new NotSupportedException("Malformed UTF-8: trailing two-byte character at end of string"); + + if ((utfBytes[i+1] & 0xC0) != 0x80) + throw new NotSupportedException("Malformed UTF-8: second byte has invalid prefix"); + + mUtfBytes.WriteByte(utfByte); + mUtfBytes.WriteByte(utfBytes[i+1]); + i += 2; + } + else if ((utfByte & 0xF0) == 0xE0) + { + // Three byte UTF-8 values are preserved as-is. + if ((i + 2) >= utfBytes.Length) + throw new NotSupportedException("Malformed UTF-8: trailing three-byte character at end of string"); + + if ((utfBytes[i+1] & 0xC0) != 0x80) + throw new NotSupportedException("Malformed UTF-8: second byte has invalid prefix"); + + if ((utfBytes[i+2] & 0xC0) != 0x80) + throw new NotSupportedException("Malformed UTF-8: third byte has invalid prefix"); + + mUtfBytes.WriteByte(utfByte); + mUtfBytes.WriteByte(utfBytes[i+1]); + mUtfBytes.WriteByte(utfBytes[i+2]); + i += 3; + + } + else + { + // Reachable when we have a non-standard four-byte sentinel mask. + throw new NotSupportedException("Malformed modified UTF-8 encoding at index " + i); + } } - WriteBufferWithInt16Length(bw, utfBytes); + WriteBufferWithInt16Length(bw, mUtfBytes.ToArray()); } /** diff --git a/crypto/test/data/jks/cacerts.jks b/crypto/test/data/jks/cacerts.jks new file mode 100644 index 000000000..ca0cbd33e --- /dev/null +++ b/crypto/test/data/jks/cacerts.jks Binary files differdiff --git a/crypto/test/src/security/test/JksStoreTest.cs b/crypto/test/src/security/test/JksStoreTest.cs index 335786f5e..8794d48a6 100644 --- a/crypto/test/src/security/test/JksStoreTest.cs +++ b/crypto/test/src/security/test/JksStoreTest.cs @@ -9,6 +9,8 @@ using Org.BouncyCastle.Crypto.Parameters; using Org.BouncyCastle.Math; using Org.BouncyCastle.Utilities.Encoders; +using Org.BouncyCastle.Utilities.Test; + namespace Org.BouncyCastle.Security.Tests { [TestFixture] @@ -177,5 +179,19 @@ namespace Org.BouncyCastle.Security.Tests // Expected } } + + [Test] + public void TestJksModifiedUtf8Roundtrip() + { + JksStore ks = new JksStore(); + Stream fIn = SimpleTest.GetTestDataAsStream("jks.cacerts.jks"); + + ks.Load(fIn, "changeit".ToCharArray()); + + MemoryStream bOut = new MemoryStream(); + ks.Save(bOut, "changedit".ToCharArray()); + + ks.Load(new MemoryStream(bOut.ToArray()), "changedit".ToCharArray()); + } } } |