diff --git a/crypto/src/asn1/DerObjectIdentifier.cs b/crypto/src/asn1/DerObjectIdentifier.cs
index 04792cbdd..7e1d5c2ff 100644
--- a/crypto/src/asn1/DerObjectIdentifier.cs
+++ b/crypto/src/asn1/DerObjectIdentifier.cs
@@ -23,6 +23,16 @@ namespace Org.BouncyCastle.Asn1
}
}
+ /// <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 @@ namespace Org.BouncyCastle.Asn1
{
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 @@ namespace Org.BouncyCastle.Asn1
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 @@ namespace Org.BouncyCastle.Asn1
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 @@ namespace Org.BouncyCastle.Asn1
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 @@ namespace Org.BouncyCastle.Asn1
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 @@ namespace Org.BouncyCastle.Asn1
if (first < '0' || first > '2')
return false;
- if (!Asn1RelativeOid.IsValidIdentifier(identifier, 2))
+ if (!Asn1RelativeOid.IsValidIdentifier(identifier, from: 2))
return false;
if (first == '2')
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