diff --git a/CHANGELOG.md b/CHANGELOG.md
index 706cae3..679dc95 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,39 +1,52 @@
-Changelog
-=========
+# Changelog
 
-#### Version 3.9.1 (2024-05-07)
+## Version 4.0.0 (2025-02-12)
+
+* Add support for utf-16 in ans1_bmp_string.dart
+* Add new oid for secp256r1 (PR #249)
+* Fix nullsafety error in padded_block_cipher_impl.dart (PR #254)
+* Fix ASN1Parser length parsing (PR #250)
+* Remove unused js dependency (PR #251)
+* Add new oids (PR #240)
+* Add new oids for elliptic curves (PR #242)
+* Add Blowfish, Camellia, Twofish block cipher engines (PR #246)
+* Reformat CHANGELOG.md to match markdown standards
+* Add factory for SHA512 in RSA-OAEP (PR #227)
+* Add generics to generateKeyPair #191
+
+## Version 3.9.1 (2024-05-07)
 
 * Add crypto in topics to pubspec.yaml (PR #237)
 * remove unnecessary ! operator from some files (PR #236)
 
-#### Version 3.9.0 (2024-04-19)
+## Version 3.9.0 (2024-04-19)
 
 * Update minimum SDK version to 3.2.0 (PR #231)
 
-#### Version 3.8.0 (2024-03-24)
+## Version 3.8.0 (2024-03-24)
 
 * Add dart2wasm support (PR #225)
 
-#### Version 3.7.4 (2024-01-15)
+## Version 3.7.4 (2024-01-15)
 
 * Support the latest version of `package:js`. (PR #220)
 * Require Dart v3.0 (PR #220)
 * Support parsing of nested objects with indefinite lengths (PR #215)
 
-#### Version 3.7.3 (2023-04-14)
+## Version 3.7.3 (2023-04-14)
 
 * PSSSigner requires only salt length to verify signature
 
-#### Version 3.7.2 (2023-03-23)
+## Version 3.7.2 (2023-03-23)
 
 * Removed duplicate oids
 
-#### Version 3.7.1 (2023-03-21)
+## Version 3.7.1 (2023-03-21)
 
 * Fix linter warnings
 * Added new oids
 
-#### Version 3.7.0 (2023-03-16)
+## Version 3.7.0 (2023-03-16)
 
 * Added RC2
 * Added RC4
@@ -46,36 +59,36 @@
 * Linting
 * Fix to BasePadding
 
-#### Version 3.6.2 (2022-09-09)
+## Version 3.6.2 (2022-09-09)
 
 * Added OIDs 2.16.840.1.114412.1.1/digiCertOVCert and
 * 2.23.140.1.2.2/organization-validated
 
-#### Version 3.6.1 (2022-06-19)
+## Version 3.6.1 (2022-06-19)
 
 * Added OID 2.5.4.26/registeredAddress
 * Support ASN1 tag 164
 
-#### Version 3.6.0 (2022-04-27)
+## Version 3.6.0 (2022-04-27)
 
 * Added ECDH Basic Agreement
 * Added ConcatKDF
 
-#### Version 3.5.2 (2022-03-07)
+## Version 3.5.2 (2022-03-07)
 
 * Added secp521r1 OID
 
-#### Version 3.5.1 (2022-02-08)
+## Version 3.5.1 (2022-02-08)
 
 * Added ASN1BMPString
 * Added emailAddress OID
 
-#### Version 3.5.0 (2021-12-30)
+## Version 3.5.0 (2021-12-30)
 
 * RSAES-OAEP with SHA256 or any digest instance.
 * Fixed bug in Keccak when updating with single bytes.
 
-#### Version 3.4.0 (2021-11-09)
+## Version 3.4.0 (2021-11-09)
 
 * Security update, fixed timing leaking in GCM implementation.
 * Fixed bug in GCM counter.
@@ -84,51 +97,51 @@
 * Security update, AESFastEngine is open to timing attacks, this has been deprecated and replaced with AESEngine.
 * validateMac in BaseAEADBlockCipher is now constant time.
 
-#### Version 3.4.0-rc2
+## Version 3.4.0-rc2
 
 * Security update, fixed timing leaking in GCM implementation.
 * Fixed bug in GCM counter.
 * Added constant time gated xor.
 * Removed more references to AESFastEngine.
 
-#### Version 3.4.0-rc1
+## Version 3.4.0-rc1
 
 * Security update, AESFastEngine is open to timing attacks, this has been deprecated and replaced with AESEngine.
 * validateMac in BaseAEADBlockCipher is now constant time.
 
-#### Version 3.3.5 (2021-10-27)
+## Version 3.3.5 (2021-10-27)
 
 * New OID
 
-#### Version 3.3.4 (2021-09-07)
+## Version 3.3.4 (2021-09-07)
 
 * Performance update to scrypt
 * SM3 implementation
 
-#### Version 3.3.3 (2021-09-03)
+## Version 3.3.3 (2021-09-03)
 
 * Argon2 in js environments.
 
-#### Version 3.3.2 (2021-08-27)
+## Version 3.3.2 (2021-08-27)
 
 * New OIDs
 
-#### Version 3.3.1 (2021-08-18)
+## Version 3.3.1 (2021-08-18)
 
 * Update to Register64 mul(...)
 * New OID
 
-#### Version 3.3.0 (2021-08-12)
+## Version 3.3.0 (2021-08-12)
 
 * ECElGamal Encryptor and Decryptor
 
-#### Version 3.2.0 (2021-07-29)
+## Version 3.2.0 (2021-07-29)
 
 * Better ASN1 Dump
 * New OIDs
 * ASN1 Fixes
 
-#### Version 3.2.0-rc0 (2021-07-05)
+## Version 3.2.0-rc0 (2021-07-05)
 
 * Extended platform detection to supply entropy source, this works on nodejs.
 * Critical fix to the examples:
@@ -139,49 +152,49 @@
 
   ```Platform.instance.platformEntropySource().getBytes(_how many_)``` to provide the seed.
 
-#### Version 3.1.3 (2021-06-29)
+## Version 3.1.3 (2021-06-29)
 
 * Add Argon2
 * Fix to ASN1 parsing, calculation of start position.
 
-#### Version 3.1.2 (2021-06-17)
+## Version 3.1.2 (2021-06-17)
 
-* Critical fixed to Blake2b and additional test vectors see https://github.com/bcgit/pc-dart/pull/108
+* Critical fixed to Blake2b and additional test vectors see <https://github.com/bcgit/pc-dart/pull/108>
 
-#### Version 3.1.1 (2021-06-04)
+## Version 3.1.1 (2021-06-04)
 
 * Updated pubspec
 
-#### Version 3.1.0 (2021-05-31)
+## Version 3.1.0 (2021-05-31)
 
 * SRP support
 * Readme correction
 * not published
 
-#### Version 3.0.1 (2021-03-24)
+## Version 3.0.1 (2021-03-24)
 
 First non-nullable-by-default release
 
-#### Version 3.0.0-nullsafety.2 (2021-02-05)
+## Version 3.0.0-nullsafety.2 (2021-02-05)
 
 * Ports this library to non-nullable-by-default, a new feature in the Dart language
 * This is a breaking change: client code (libraries and apps) will have to migrate as well to use new releases of this
   library.
 * This library's existing APIs should not have changed functionally from Version 2.0.1; any such change should be
-  reported at https://github.com/bcgit/pc-dart/issues
+  reported at <https://github.com/bcgit/pc-dart/issues>
 * The block cipher modes IGE and CCM were also added in this update.
-* More info about migration: https://dart.dev/null-safety/migration-guide
-* More info about null safety: https://dart.dev/null-safety
+* More info about migration: <https://dart.dev/null-safety/migration-guide>
+* More info about null safety: <https://dart.dev/null-safety>
 
-#### Version 3.0.0-nullsafety.1
+## Version 3.0.0-nullsafety.1
 
 * not published
 
-#### Version 3.0.0-nullsafety.0
+## Version 3.0.0-nullsafety.0
 
 * not published
 
-#### Version 2.0.1 (2021-01-16)
+## Version 2.0.1 (2021-01-16)
 
 * Bug fix, ASN1Utils
 * Removal of 'dart:io'
@@ -192,23 +205,24 @@
 decodeBigInt and encodeBigInt.
 
 **utils.dart:**
-- decodeBigInt is twos compliment.
-- encodeBigInt is twos compliment and adds padding to preserve sign.
-- encodeBigIntAsUnsigned writes the magnitude without any padding.
-- decodeBigIntWithSign allows the specification of an arbitrary sign.
-- Previous uses of decodeBigInt where the expectation is an unsigned integer have been updated with
+
+* decodeBigInt is twos compliment.
+* encodeBigInt is twos compliment and adds padding to preserve sign.
+* encodeBigIntAsUnsigned writes the magnitude without any padding.
+* decodeBigIntWithSign allows the specification of an arbitrary sign.
+* Previous uses of decodeBigInt where the expectation is an unsigned integer have been updated with
   decodeBigIntWithSign(1, magnitude).
 
-#### Version 2.0.0 (2020-10-02)
+## Version 2.0.0 (2020-10-02)
 
 * No changes from 2.0.0-rc2
 
-#### Version 2.0.0-rc2 (2020-09-25)
+## Version 2.0.0-rc2 (2020-09-25)
 
 * Linter Fixes
 * Updates to ASN1 API
 
-#### Version 2.0.0-rc1 (2020-09-11) (Dart SDK version 2.1.1)
+## Version 2.0.0-rc1 (2020-09-11) (Dart SDK version 2.1.1)
 
 * Fixed OAEPEncoding and PKCS1Encoding to use provided output offset value.
 * Fixed RSA block length and offset checks in RSAEngine.processBlock.
@@ -221,40 +235,39 @@
 * Reduce copies in CBC mode.
 * Linter issues fixed.
 * FixedSecureRandom to use seed only once.
-* ASN1 - BOOLEAN, INTEGER, BIT_STRING, OCTET_STRING, NULL, OBJECT_IDENTIFIER, 
+* ASN1 - BOOLEAN, INTEGER, BIT_STRING, OCTET_STRING, NULL, OBJECT_IDENTIFIER,
   ENUMERATED, UTF8_STRING, SEQUENCE, SET, PRINTABLE_STRING, IA5_STRING & UTC_TIME
 * ASN1 Encoding - DER & BER
 * RSA Keys - Private Key carries public key exponent, added publicExponent and privateExponent where necessary
   and deprecated single variable getters in for those values.
 
-##### Thanks, Steven
- At this release the Point Castle Crypto API has been fully handed over to the 
- Legion of the Bouncy Castle Inc. Steven Roose, it is no small thing to single headedly 
- manage a cryptography API and your effort is rightfully respected by the Pointy Castle user 
+### Thanks, Steven
+
+ At this release the Point Castle Crypto API has been fully handed over to the
+ Legion of the Bouncy Castle Inc. Steven Roose, it is no small thing to single headedly
+ manage a cryptography API and your effort is rightfully respected by the Pointy Castle user
  base. We would like to thank you for your trust in us to carry the project forward, and we
  wish you all the best!
   
-  
-#### Version 1.0.2 (2019-11-15)
+## Version 1.0.2 (2019-11-15)
 
 * Add non-Keccak SHA3 support
 * Add CMAC support ("AES/CMAC")
 * Add ISO7816-4 padding support
 * Fixes in CBCBlockCipherMac and CMac
 
-#### Version 1.0.1 (2019-02-20)
+## Version 1.0.1 (2019-02-20)
 
 * Add Blake2b support
 
-#### Version 1.0.0 (2018-12-17) (Dart SDK version 2.0)
+## Version 1.0.0 (2018-12-17) (Dart SDK version 2.0)
 
 * Support Dart 2 and Strong Mode
 * Migrate from `package:bignum.BigInteger` to `dart:core.BigInt`
 * Remove Quiver and fixnum dependency
 * OAEP encoding for block ciphers
 
-
-#### Version 0.10.0 (2016-02-04) (Dart SDK version 0.14.0)
+## Version 0.10.0 (2016-02-04) (Dart SDK version 0.14.0)
 
 * First Pointy Castle release.
 
@@ -265,17 +278,15 @@
 
 * Migrated from unittest to test package.
 
-
 ### cipher releases
 
-#### Version 0.8.0 (2014-??-??) (Dart SDK version ???)
+## Version 0.8.0 (2014-??-??) (Dart SDK version ???)
 
-* **[bug 80]** PaddedBlockCipher doesn't add padding when data length is a multiple of the block 
+* **[bug 80]** PaddedBlockCipher doesn't add padding when data length is a multiple of the block
                 size. This fix introduces a **BREAKING CHANGE** in PaddedBlockCipher specification.
                 Read its API documentation to know about the changes.
 
-
-#### Version 0.7.0 (2014-03-22) (Dart SDK version 1.3.0-dev.5.2)
+## Version 0.7.0 (2014-03-22) (Dart SDK version 1.3.0-dev.5.2)
 
 * **[enh 15]** Implement stream cipher benchmarks.
 * **[enh 64]** Benchmark and optimize digests.
diff --git a/pubspec.yaml b/pubspec.yaml
index b04d42a..c4571de 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,9 +1,12 @@
 name: pointycastle
-version: 3.9.1
+version: 4.0.0
 description: A Dart library implementing cryptographic algorithms and primitives, modeled on the BouncyCastle library.
 homepage: https://github.com/bcgit/pc-dart
 topics:
  - crypto
+ - rsa
+ - ecc
+ - asn1
 
 environment:
   sdk: ^3.2.0