Patch #1 for 2.3

- TLS: fix timing side-channel for RSA key exchange
- fix method Write(ReadOnlySpan<byte>) in LimitedBuffer
- ASN.1: Limit OID contents to 4096 bytes
- EdDSA: fix verification infinite loop
- EC: restrict m value in F2m curves

crypto/Contributors.html

@@ -268,9 +268,9 @@ <h3>Code Contributors:</h3>
  <li>
  <p>Matthew Sitton (https://github.com/mdsitton) - Addition of missing ALPN Protocol names.</p>
  </li>
-  <li>
- <p>Jozef Gajdo&scaron; (https://github.com/harrison314) - Time constructor optimization, RevokedStatus fix, improved thread-safe singleton code (e.g. X509Certificate/X509Crl cached encoding), SubjectPublicKeyInfo support in OpenSsl.PemWriter.</p>
-  </li>
+  <li>
+ <p>Jozef Gajdo&scaron; (https://github.com/harrison314) - Time constructor optimization, RevokedStatus fix, improved thread-safe singleton code (e.g. X509Certificate/X509Crl cached encoding), SubjectPublicKeyInfo support in OpenSsl.PemWriter, fixed PSS raw signing over spans.</p>
+  </li>
  <li>
  <p>Ben Adams (https://github.com/benaadams) - Performance optimization for AES-NI.</p>
  </li>

crypto/Readme.html

@@ -31,6 +31,8 @@ <h3><a class="mozTocH3" name="mozTocId685176"></a>Contents:<br /></h3>
  <li>
  <a href="#mozTocId3413">Notes:</a>
  <ol>
+ <li>
+ <a href="#mozTocId85332">Release 2.3.1</a>
  <li>
  <a href="#mozTocId85331">Release 2.3.0</a>
  <li>
@@ -329,6 +331,27 @@ <h3><a class="mozTocH3" name="mozTocId358608"></a>For first time users.</h3>
  <hr style="WIDTH: 100%; HEIGHT: 2px">
  <h3><a class="mozTocH3" name="mozTocId3413"></a>Notes:</h3>
 
+ <h4><a class="mozTocH4" name="mozTocId85332"></a>Release 2.3.1, Tuesday May 7, 2024</h4>
+ <h5>Defects Fixed</h5>
+ <ul>
+ <li>TLS: Fixed timing side-channel for RSA key exchange ("The Marvin Attack").</li>
+ <li>PSS: Fixed regression in 2.3.0 when updating signer from a span.</li>
+ <li>EdDSA: Fixed verification infinite loop (regression in 2.1.0)
+ - see <a href="https://github.com/bcgit/bc-java/issues/1599">corresponding bc-java issue</a>.</li>
+ </ul>
+ <h5>Additional Features and Functionality</h5>
+ <ul>
+ <li>ASN.1: Limited OID contents to 4096 bytes.</li>
+ <li>EC: Restricted m value in F2m curves.</li>
+ </ul>
+ <h5>Additional Notes</h5>
+ <ul>
+ <li>
+ See the (cumulative) list of GitHub pull requests that we have accepted at
+ <a href="https://github.com/bcgit/bc-csharp/pulls?q=is%3Apr+is%3Aclosed">bcgit/bc-csharp</a>.
+ </li>
+ </ul>
+
  <h4><a class="mozTocH4" name="mozTocId85331"></a>Release 2.3.0, Monday February 5, 2024</h4>
  <h5>Defects Fixed</h5>
  <ul>

crypto/src/asn1/Asn1InputStream.cs

@@ -377,7 +377,9 @@ internal static Asn1Object CreatePrimitiveDerObject(int tagNo, DefiniteLengthInp
  switch (tagNo)
  {
  case Asn1Tags.BmpString:
+ {
  return CreateDerBmpString(defIn);
+ }
  case Asn1Tags.Boolean:
  {
  GetBuffer(defIn, tmpBuffers, out var contents);
@@ -390,9 +392,16 @@ internal static Asn1Object CreatePrimitiveDerObject(int tagNo, DefiniteLengthInp
  }
  case Asn1Tags.ObjectIdentifier:
  {
+ DerObjectIdentifier.CheckContentsLength(defIn.Remaining);
  bool usedBuffer = GetBuffer(defIn, tmpBuffers, out var contents);
  return DerObjectIdentifier.CreatePrimitive(contents, clone: usedBuffer);
  }
+ case Asn1Tags.RelativeOid:
+ {
+ Asn1RelativeOid.CheckContentsLength(defIn.Remaining);
+ bool usedBuffer = GetBuffer(defIn, tmpBuffers, out var contents);
+ return Asn1RelativeOid.CreatePrimitive(contents, clone: usedBuffer);
+ }
  }
 
  byte[] bytes = defIn.ToArray();
@@ -421,8 +430,6 @@ internal static Asn1Object CreatePrimitiveDerObject(int tagNo, DefiniteLengthInp
  return Asn1OctetString.CreatePrimitive(bytes);
  case Asn1Tags.PrintableString:
  return DerPrintableString.CreatePrimitive(bytes);
- case Asn1Tags.RelativeOid:
- return Asn1RelativeOid.CreatePrimitive(bytes, false);
  case Asn1Tags.T61String:
  return DerT61String.CreatePrimitive(bytes);
  case Asn1Tags.UniversalString:

crypto/src/asn1/Asn1RelativeOid.cs

@@ -22,6 +22,16 @@ internal override Asn1Object FromImplicitPrimitive(DerOctetString octetString)
  }
  }
 
+ /// <summary>Implementation limit on the length of the contents octets for a Relative OID.</summary>
+ /// <remarks>
+ /// We adopt the same value used by OpenJDK for Object Identifier. In theory there is no limit on the length of
+ /// the contents, or the number of subidentifiers, or the length of individual subidentifiers. In practice,
+ /// supporting arbitrary lengths can lead to issues, e.g. denial-of-service attacks when attempting to convert a
+ /// parsed value to its (decimal) string form.
+ /// </remarks>
+ private const int MaxContentsLength = 4096;
+ private const int MaxIdentifierLength = MaxContentsLength * 4 - 1;
+
  public static Asn1RelativeOid FromContents(byte[] contents)
  {
  if (contents == null)
@@ -68,14 +78,18 @@ public static bool TryFromID(string identifier, out Asn1RelativeOid oid)
  {
  if (identifier == null)
  throw new ArgumentNullException(nameof(identifier));
- if (!IsValidIdentifier(identifier, 0))
+ if (identifier.Length <= MaxIdentifierLength && IsValidIdentifier(identifier, from: 0))
  {
- oid = default;
- return false;
+ byte[] contents = ParseIdentifier(identifier);
+ if (contents.Length <= MaxContentsLength)
+ {
+ oid = new Asn1RelativeOid(contents, identifier);
+ return true;
+ }
  }
 
- oid = new Asn1RelativeOid(ParseIdentifier(identifier), identifier);
- return true;
+ oid = default;
+ return false;
  }
 
  private const long LongLimit = (long.MaxValue >> 7) - 0x7F;
@@ -85,31 +99,13 @@ public static bool TryFromID(string identifier, out Asn1RelativeOid oid)
 
  public Asn1RelativeOid(string identifier)
  {
- if (identifier == null)
- throw new ArgumentNullException("identifier");
- if (!IsValidIdentifier(identifier, 0))
- throw new FormatException("string " + identifier + " not a relative OID");
-
- m_contents = ParseIdentifier(identifier);
- m_identifier = identifier;
- }
-
- private Asn1RelativeOid(Asn1RelativeOid oid, string branchID)
- {
- if (!IsValidIdentifier(branchID, 0))
- throw new FormatException("string " + branchID + " not a valid relative OID branch");
-
- m_contents = Arrays.Concatenate(oid.m_contents, ParseIdentifier(branchID));
- m_identifier = oid.GetID() + "." + branchID;
- }
+ CheckIdentifier(identifier);
 
- private Asn1RelativeOid(byte[] contents, bool clone)
- {
- if (!IsValidContents(contents))
- throw new ArgumentException("invalid relative OID contents", nameof(contents));
+ byte[] contents = ParseIdentifier(identifier);
+ CheckContentsLength(contents.Length);
 
- m_contents = clone ? Arrays.Clone(contents) : contents;
- m_identifier = null;
+ m_contents = contents;
+ m_identifier = identifier;
  }
 
  private Asn1RelativeOid(byte[] contents, string identifier)
@@ -120,7 +116,14 @@ private Asn1RelativeOid(byte[] contents, string identifier)
 
  public virtual Asn1RelativeOid Branch(string branchID)
  {
- return new Asn1RelativeOid(this, branchID);
+ CheckIdentifier(branchID);
+
+ byte[] branchContents = ParseIdentifier(branchID);
+ CheckContentsLength(m_contents.Length + branchContents.Length);
+
+ return new Asn1RelativeOid(
+ contents: Arrays.Concatenate(m_contents, branchContents),
+ identifier: GetID() + "." + branchID);
  }
 
  public string GetID()
@@ -165,9 +168,30 @@ internal sealed override DerEncoding GetEncodingDerImplicit(int tagClass, int ta
  return new PrimitiveDerEncoding(tagClass, tagNo, m_contents);
  }
 
+ internal static void CheckContentsLength(int contentsLength)
+ {
+ if (contentsLength > MaxContentsLength)
+ throw new ArgumentException("exceeded relative OID contents length limit");
+ }
+
+ internal static void CheckIdentifier(string identifier)
+ {
+ if (identifier == null)
+ throw new ArgumentNullException(nameof(identifier));
+ if (identifier.Length > MaxIdentifierLength)
+ throw new ArgumentException("exceeded relative OID contents length limit");
+ if (!IsValidIdentifier(identifier, from: 0))
+ throw new FormatException("string " + identifier + " not a valid relative OID");
+ }
+
  internal static Asn1RelativeOid CreatePrimitive(byte[] contents, bool clone)
  {
- return new Asn1RelativeOid(contents, clone);
+ CheckContentsLength(contents.Length);
+
+ if (!IsValidContents(contents))
+ throw new ArgumentException("invalid relative OID contents", nameof(contents));
+
+ return new Asn1RelativeOid(clone ? Arrays.Clone(contents) : contents, identifier: null);
  }
 
  internal static bool IsValidContents(byte[] contents)

crypto/src/asn1/DerObjectIdentifier.cs

@@ -23,6 +23,16 @@ internal override Asn1Object FromImplicitPrimitive(DerOctetString octetString)
  }
  }
 
+ /// <summary>Implementation limit on the length of the contents octets for an Object Identifier.</summary>
+ /// <remarks>
+ /// We adopt the same value used by OpenJDK. In theory there is no limit on the length of the contents, or the
+ /// number of subidentifiers, or the length of individual subidentifiers. In practice, supporting arbitrary
+ /// lengths can lead to issues, e.g. denial-of-service attacks when attempting to convert a parsed value to its
+ /// (decimal) string form.
+ /// </remarks>
+ private const int MaxContentsLength = 4096;
+ private const int MaxIdentifierLength = MaxContentsLength * 4 + 1;
+
  public static DerObjectIdentifier FromContents(byte[] contents)
  {
  if (contents == null)
@@ -86,14 +96,18 @@ public static bool TryFromID(string identifier, out DerObjectIdentifier oid)
  {
  if (identifier == null)
  throw new ArgumentNullException(nameof(identifier));
- if (!IsValidIdentifier(identifier))
+ if (identifier.Length <= MaxIdentifierLength && IsValidIdentifier(identifier))
  {
- oid = default;
- return false;
+ byte[] contents = ParseIdentifier(identifier);
+ if (contents.Length <= MaxContentsLength)
+ {
+ oid = new DerObjectIdentifier(contents, identifier);
+ return true;
+ }
  }
 
- oid = new DerObjectIdentifier(ParseIdentifier(identifier), identifier);
- return true;
+ oid = default;
+ return false;
  }
 
  private const long LongLimit = (long.MaxValue >> 7) - 0x7F;
@@ -105,22 +119,13 @@ public static bool TryFromID(string identifier, out DerObjectIdentifier oid)
 
  public DerObjectIdentifier(string identifier)
  {
- if (identifier == null)
- throw new ArgumentNullException("identifier");
- if (!IsValidIdentifier(identifier))
- throw new FormatException("string " + identifier + " not an OID");
+ CheckIdentifier(identifier);
 
- m_contents = ParseIdentifier(identifier);
- m_identifier = identifier;
- }
+ byte[] contents = ParseIdentifier(identifier);
+ CheckContentsLength(contents.Length);
 
- private DerObjectIdentifier(byte[] contents, bool clone)
- {
- if (!Asn1RelativeOid.IsValidContents(contents))
- throw new ArgumentException("invalid OID contents", nameof(contents));
-
- m_contents = clone ? Arrays.Clone(contents) : contents;
- m_identifier = null;
+ m_contents = contents;
+ m_identifier = identifier;
  }
 
  private DerObjectIdentifier(byte[] contents, string identifier)
@@ -131,11 +136,13 @@ private DerObjectIdentifier(byte[] contents, string identifier)
 
  public virtual DerObjectIdentifier Branch(string branchID)
  {
- if (!Asn1RelativeOid.IsValidIdentifier(branchID, 0))
- throw new FormatException("string " + branchID + " not a valid OID branch");
+ Asn1RelativeOid.CheckIdentifier(branchID);
+
+ byte[] branchContents = Asn1RelativeOid.ParseIdentifier(branchID);
+ CheckContentsLength(m_contents.Length + branchContents.Length);
 
  return new DerObjectIdentifier(
- contents: Arrays.Concatenate(m_contents, Asn1RelativeOid.ParseIdentifier(branchID)),
+ contents: Arrays.Concatenate(m_contents, branchContents),
  identifier: GetID() + "." + branchID);
  }
 
@@ -195,9 +202,27 @@ internal sealed override DerEncoding GetEncodingDerImplicit(int tagClass, int ta
  return new PrimitiveDerEncoding(tagClass, tagNo, m_contents);
  }
 
+ internal static void CheckContentsLength(int contentsLength)
+ {
+ if (contentsLength > MaxContentsLength)
+ throw new ArgumentException("exceeded OID contents length limit");
+ }
+
+ internal static void CheckIdentifier(string identifier)
+ {
+ if (identifier == null)
+ throw new ArgumentNullException(nameof(identifier));
+ if (identifier.Length > MaxIdentifierLength)
+ throw new ArgumentException("exceeded OID contents length limit");
+ if (!IsValidIdentifier(identifier))
+ throw new FormatException("string " + identifier + " not a valid OID");
+ }
+
  internal static DerObjectIdentifier CreatePrimitive(byte[] contents, bool clone)
  {
- int index = Arrays.GetHashCode(contents);
+ CheckContentsLength(contents.Length);
+
+ uint index = (uint)Arrays.GetHashCode(contents);
 
  index ^= index >> 20;
  index ^= index >> 10;
@@ -207,7 +232,10 @@ internal static DerObjectIdentifier CreatePrimitive(byte[] contents, bool clone)
  if (originalEntry != null && Arrays.AreEqual(contents, originalEntry.m_contents))
  return originalEntry;
 
- var newEntry = new DerObjectIdentifier(contents, clone);
+ if (!Asn1RelativeOid.IsValidContents(contents))
+ throw new ArgumentException("invalid OID contents", nameof(contents));
+
+ var newEntry = new DerObjectIdentifier(clone ? Arrays.Clone(contents) : contents, identifier: null);
 
  var exchangedEntry = Interlocked.CompareExchange(ref Cache[index], newEntry, originalEntry);
  if (exchangedEntry != originalEntry)
@@ -228,7 +256,7 @@ private static bool IsValidIdentifier(string identifier)
  if (first < '0' || first > '2')
  return false;
 
- if (!Asn1RelativeOid.IsValidIdentifier(identifier, 2))
+ if (!Asn1RelativeOid.IsValidIdentifier(identifier, from: 2))
  return false;
 
  if (first == '2')