## v1.1.0 (2026-06-24)

* Add Signing_request.sign_certificate which takes the issuer as certificate and
  does some validity checks (#182 @hannesm)
* Document the need for checking KeyUsage/ExtendedKeyUsage extensions in
  Validation functions (#182 @hannesm)
* If a CA certificate has a extendedKeyUsage, it must contain Any or Server_auth
  (#182 @hannesm)
* Restrict server certificates to not have a Name_constraints extension
  (#182 @hannesm)
* Add validation of name constraints when validating the chain of trust
  (#182 @hannesm)

The last 3 fixes were tested with bettertls from Netflix.

## v1.0.6 (2025-04-15)

* Update tests to mirage-crypto-rng 1.2.0 API (@hannesm)
* Certificate.fold_pem_multiple: improve error message (#180 @hannesm)

## v1.0.5 (2024-10-28)

* Removed links to nqsb (we're no longer in charge of that domain)
  (6398b0c2a24e1a09d494d93ac65423eca9d7de24)

## v1.0.4 (2024-09-29)

* **breaking change** Allow decoding of negative serial numbers (#177 @hannesm)
  Now, `serial` returns the entire (integer) value as a string - previously the
  potentially leading 0 byte was removed. So:
  -serial d795 49bd 1a67 1751
  +serial 00d7 9549 bd1a 6717  51
  fixes in 38cc70a54d2d98526564733838769d82b10679fc and #179 (#178 @dinosaure)
* Add alternate SHA1RSA OID 1.3.14.3.2.29 (#176 @mefyl)
* Allow custom pretty printers for unknown X509 extensions (#175 @reynir)
* Minor code cleanups: remove unused algorithms, remove `def` and `def'`
  (#177 @hannesm)

## v1.0.3 (2024-09-04)

* Use the opam package kdf instead of pbkdf (@hannesm #174)

## v1.0.2 (2024-08-25)

* Fix RSA public and private key encoding and decoding (@hannesm #172, reported
  by @anmonteiro #171)

## v1.0.1 (2024-08-06)

* Speedup PEM decoding and encoding significantly (@hannesm #170)

## v1.0.0 (2024-07-20)

* **breaking change** Replace `Cstruct.t` by `string` (@dinosaure, @hannesm, #167)
* Remove P224 (@dinosaure, @hannes, #166) - which was removed in mirage-crypto-ec 1.0.0
* **breaking change** The serial number of certificates is a `string` and enforced to be a positive
  integer of at most 20 bytes in length (@hannesm, #167)
* **breaking change** `Authenticator.server_key_fingerprint` and
  `Authenticator.server_cert_fingerprint` are now known as
  `Authenticator.key_fingerprint` and `Authenticator.cert_fingerprint`
  respectively to better reflect that they do not check extended key usage is
  "server" and may as well be used for authenticating clients (@reynir, #164)
* Add Certificate.fold_decode_pem_multiple to decode multiple pem encoded certificates and make the error handling explicit (ignore, log, fail on first error). Motivated by mirage/ca-certs#30 (@art-w #169)

## v0.16.5 (2023-07-03)

* Always embed local_key_id in PKCS12 bags (reported #163 by @NightBlues,
  revised and implemented by @hannesm)

## v0.16.4 (2023-02-13)

* Adapt to mirage-crypto-rng 0.11.0 API changes (#162 @hannesm)

## v0.16.3 (2023-02-04)

* Validation: allow self-signed server certificate with BasicConstraints CA=true
  (reported by @mbacarella in mirleft/ocaml-tls#446
   (https://github.com/lightningnetwork/lnd/issues/5450), fix #161 by @hannesm)

## v0.16.2 (2022-10-05)

* Improve parse error message of Authenticator.of_string (mirage/ocaml-git#593
  by @dinosaure, mirage/ocaml-git#582 by @reynir)

## v0.16.1 (2022-09-14)

* Support ECDSA signatures where the hash algorithm output length exceeds the
  size of the elliptic curve (by truncating, and using the leftmost bits).
  Reported as #158 by @torinnd, fixed in #159 by @hannesm

## v0.16.0 (2022-02-15)

* Provide X509.Authenticator.of_string to construct an Authenticator.t from
  a string (@dinosaure #156, reviewed by @hannesm)
* Minor documentation fixes (#157 @hannesm)

## v0.15.2 (2021-11-22)

* Provide X509.Private_key.of_string (as used by awa and dns-certify). This
  takes a b64 encoded raw private key or a seed. (@reynir @hannesm #155)

## v0.15.1 (2021-10-26)

* avoid usae of deprecated functions of fmt (@hannesm)
* remove rresult dependency (@hannesm)

## v0.15.0 (2021-09-27)

* FEATURE support validation of an IP address in the leaf certificate
  (#152 #153 @reynir @hannesm)
* FEATURE provide Certificate.ips and Certificate.supports_ip
  (#152 @reynir @hannesm)
* BREAKING revise certificate and public key fingerprint authenticators API:
  now a single fingerprint is supported, previously a list of pairs of
  hostname and fingerprint was used (#153 @hannesm)
* BREAKING The Authenticator.t type has been extended with ?ip:Ipaddr.t
  (#153 @hannesm)

## v0.14.1 (2021-08-04)

* Use Cstruct.length instead of deprecated Cstruct.len, bump minimum cstruct
  to 6.0.0 (#151 by @hannesm)

## v0.14.0 (2021-06-17)

* FEATURE support Online Certificate Status Protocol (OCSP, RFC 6960)
  (#148 @NightBlues, #149 @hannesm)

## v0.13.0 (2021-04-22)

* FEATURE support for RFC 5915 "BEGIN EC PRIVATE KEY" pem encoded private keys
  (#147 @hannesm, requested by @ulrikstrid)
* BREAKING remove EC_pub _ from Public_key.t and EC _ from Certificate.key_type
  (#147 by @hannesm)
* BREAKING move Certificate.key_type to Key_type.t (#147 @hannesm)
* FEATURE some private key utilities (of_cstruct, generate, sign), and
  Public_key.verify (#report #146, fix #147 @hannesm)
* BREAKING rename hash_whitelist to allowed_hashes (#147 @hannesm)
* BREAKING provide Key_type.signature_scheme and use across the API
  (#147 @hannesm)

## v0.12.0 (2021-04-05)

* FEATURE PKCS12 support (#114 by @hannesm)
* FEATURE ECDSA and EDDSA support via mirage-crypto-ec (#145 by @hannesm)
  This breaks some clients since the Private_key.t and Public_key.t variants
  are extended (may result in partial pattern matches of users of this library).
* CRL.is_revoked has `crls` as last parameter to avoid warning 16
  (4.12 compatibility) (#144 by @hannesm)
* Signing_request.sign: add optional labelled argument `~subject` to allow
  changing the subject when signing a signing request (#139 by @reynir)
* BUGFIX Encoding of Distinguished_name components (adhere to specification)
  DomainComponent and EMail are now serialised using a IA5String; Serialnumber,
  CountryName and DnQualifier as PrintableString (reported in #69, fixed #140
  by @NightBlues)
* BREAKING Remove `~sloppy` from Private_key.decode_{pem,der}. The seemingly
  bad RSA keys were valid and should have been accepted by mirage-crypto.
  (#142 by @psafont)

## v0.11.2 (2020-05-14)

* Private_key.decode_{pem,der} now has a `~sloppy` option to recover from
  bad keys (where e.g. the private exponent d is wrong).
  (#135 by @hannesm, reported by @mattjbray in mirage/mirage-crypto#62)

## v0.11.1 (2020-04-27)

* open variant for errors to make the composable (#133 by @dinosaure,
  review by @hannesm)
* BUGFIX avoid fractional seconds in generalized_time: truncate on serialising,
  validate them to be 0 on deserialising, as required in RFC 5280 4.1.2.5.2
  (#134 by @hannesm, reported by @ansiwen)

## v0.11.0 (2020-04-07)

* BREAKING Validation.validate_raw_signature results in a
  `(unit, signature_error) result` and logs (Logs.warn) if a weak (non-SHA2)
  hash algorithm was used. This function is used for verifying signatures
  on certificates, signing requests, and certificate revocation lists.
* The `` `CAInvalidSelfSignature `` constructor (Validation.ca_error) and
  `` `ChainInvalidSignature `` constructor (Validation.chain_validation_error)
  have been removed.
* BREAKING The polymorphic variant `Validation.chain_error` is now flat (the
  tags `` `Chain `` and `` `Leaf `` have been removed)
* BREAKING Adapted return type of CRL.validate and CRL.verify
* The pretty-printer Public_key.pp is now provided
* All implemented by @hannesm in #132 based on private conversation with @cfcs
  (who kindly reviewed the changes)

## v0.10.0 (2020-03-11)

* BREAKING #131 use mirage-crypto and mirage-crypto-pk instead of nocrypto
  raise lower OCaml bound to 4.07.0, test 4.10.0 in CI
* BREAKING #131 Certificate.Host_set is now Host.Set, and has pretty-printers
* BREAKING #131 Authenticator.null was removed (fixes #130, suggested by @emillon)
* BREAKING #131 Authenticator.t now requires (non-optional) ~host and ~time
  arguments which may return an option. This allows to more easily spot the
  cases where None is provided. Also, time is (unit -> Ptime.t option) instead
  of Ptime.t -- thus the timestamp at the time of certificate verification is
  used instead of the time of Authenticator construction. Similar changes in
  Validation for verify_chain, verify_chain_of_trust, trust_key_fingerprint,
  trust_cert_fingerprint.
  fixes #130, suggested by @emillon

## v0.9.0 (2020-01-22)

* BREAKING add a whitelist of hash algorithms used for signatures. The default
  whitelist is the SHA-2 family (without SHA-224), Validation.valid_ca{,s} use
  all algorithms as default
  reported by @emillon in #123, fixed in #128
* BREAKING Certificate.hostnames and Signing_request.hostnames (new) return a
  set of [`Wildcard|`Strict] * [`host] Domain_name.t (Certificate.Host_set.t)
  reported by @mmaker in #88, fixed in #127
* BREAKING #127 Signing_request.sign returns a result type now, an error is
  returned if the signing request was not properly signed
* BREAKING #127 Validation.{verify_chain_of_trust, trust_key_fingerprint,
  trust_cert_fingerptint} and the type Authenticator.t changed, no longer use
  of a Certificate.host, but instead a [`host] Domain_name.t (previously, it was
  a pair)
* BUGFIX support AlgorithmIdentifier of RSA signature algorithms with parameter
  not present
  reported by @Ulrar in #108, fixed in #129
* BUGFIX #127 preserve a signed signing request (Country in a DN sometimes uses
  a non-utf8 string encoding)
* remove deprecation from Validation.trust_cert_fingerprint and
  Authenticator.server_cert_fingerprint
  requested by @mben-romdhane in #125, fixed in #126
* Certificate.signature_algorithm, CRL.signature_algorithm, and
  Signing_request.signature_algorithm are now provided, returning a
  ([`RSA|`ECDSA] * Nocrypto.Hash.hash) option
  requested by @psafont in #123, fixed in #128

## v0.8.1 (2019-10-10)

* export Private_key.decode_der and encode_der

## v0.8.0 (2019-10-10)

* export X509.Distinguished_name.common_name : t -> string option, which
  extracts the common name of a distinguished name
* Distinguished_name.t is now a Relative_distinguished_name.t list, a
  Relative_distinguished_name is a Set.S with element type attribute, a variant.
  It used to be an attribute (expressed as GADT) Gmap.t, but this representation
  did not conform to RFC 5280, reported by @paurkedal (#117, fixed by #118)
* Now using Set.find_first_opt, which bumps lower OCaml bound to 4.05.0
* Improved pretty-printing for DNs including RFC 4514 conformance (@paurkedal, #119).
* Extension.pp now outputs extension key and its value (#120)
* rename Distinguished_name.SP constructor (stateOrProvince) to ST, as widely used (#121)
* support Street and UID in Distinguished_name to satisfy RFC 4514 demands (#121)

## v0.7.1 (2019-08-09)

* revert General_name.t (DNS and IP components) to string/Cstruct.t list
  - NameConstraints uses DNSname with strings with leading dots (.example.com),
    which are not valid RFC1034 domain names
  - NameConstraints uses IP with IP/netmask, i.e. using 8 octets for an IPv4
    address
  - X509.Certificate.hostnames still return a Domain_name.Set.t
  - reported by @reynir
* drop ipaddr dependency

## 0.7.0 (2019-07-24)

* major restructuring, it is unlikely any pre-0.7.0 users will work with 0.7.0+
* remove sexp de&encoders
* provide pretty-printers for validation errors (and types) instead of to_string functions
* use result type and Rresult instead of custom result types and control monad
* use a GADT map for certificate & csr extensions, distinguished names, general names (avoiding multiple extensions with the same OID, uses the gmap library)
* use domain-name library for hostname validation (instead of custom string matching)
* use ipaddr library for IPs in SubjectAlternativeName extension
* remove Encoding module, provide {en,de}code_{der,pem} in the respective modules (which decoders return (_, [> `Msg of string ]) result, no exceptions raised)
* fix DistributionPoint extension: the CRLissuer is a GeneralName, not a DistinguishedName
* remove Extension.reason_code (Extension.reason was there before, and is now used)
* remove bindings from toplevel, t is now Certificate.t, public_key is now Public_key.t
* use alcotest instead of oUnit

## 0.6.3 (2019-04-02)

* provide X509.Encoding.distinguished_name_of_cs -- similar to #87 which provided distinguished_name_to_cs
* provide X509.Encoding.{public_key_of_cstruct,public_key_to_cstruct}, as requested by @dinosaure
* support of cstruct 4.0.0, which split up the sexp de&encoders
* removes result dependency (now requires >= 4.04.2)
* upgrades opam file to version 2.0
* build system is now dune

## 0.6.2 (2018-08-24)

* compatibility with ppx_sexp_conv >v0.11.0 (#109), required for 4.07.0

## 0.6.1 (2017-12-21)

* provide X509.distinguished_name sexp converter (#103)
* drop non-exported X509_types module from distinguished_name (#102, @yomimono)

## 0.6.0 (2017-12-13)

* Certificate Revocation List (CRL) support (#99)
* track asn1-combinators 0.2.0 changes (#97)
* provide Extension.subject_alt_names (#95)
* compute length of certificate length, instead of hardcoding 4 (#95)
* enable safe-string (#89)
* use astring instead of custom String_ext.split (#89)
* use topkg instead of oasis (#88, #89)
* provide Encoding.cs_of_distinguished_name (#87 by @reynir)

## 0.5.3 (2016-09-13)

* provide Encoding.parse_signing_request and Encoding.cs_of_signing_request (#81)
* provide validity : t -> (Time.t * Time.t) (#86, fixes #85)

## 0.5.2 (2016-04-13)

* fix building of certificate paths

## 0.5.1 (2016-03-21)

* use ppx_sexp_conv instead of sexplib.syntax
* no more Stream syntax, use lists

## 0.5.0 (2015-12-04)

* avoid dependency on sexplib.syntax (#55)
* document how to combine extensions and a CSR into a certificate (@reynir, #63 #64)
* expose `fingerprint : t -> hash -> Cstruct.t`, the hash of the certificate (@cfcs, #66)
* trust_fingerprint / server_fingerprint are renamed to trust_cert_fingerprint / server_cert_fingerprint (now deprecated!)
* fingerprint public keys (rather than certificates): trust_key_fingerprint / server_key_fingerprint
* build certificate paths from the received set (RFC 4158) instead of requiring a strict chain (#74)
* the given trust anchors to `Authenticator.chain_of_trust` are not validated (to contain KeyUsage / BasicConstraint extensions) anymore, users can use `valid_ca` and `valid_cas` to filter CAs upfront

## 0.4.0 (2015-07-02)

* certificate signing request support (PKCS10)
* basic CA functionality (in CA module): create and sign certificate signing requests
* PEM encoding of X.509 certificates, RSA public and private keys, and certificate signing requests
* new module Extension contains X509v3 extensions as polymorphic variants
* expose distinguished_name as polymorphic variant
* type pubkey is now public_key
* function cert_pubkey is now public_key
* functions supports_usage, supports_extended_usage are now in Extension module
* types key_usage, extended_key_usage are now in Extension module
* Encoding.Pem.Cert has been renamed to Encoding.Pem.Certificate
* Encoding.Pem.PK has been renamed to Encoding.Pem.Private_key (now uses type private_key instead of Nocrypto.Rsa.priv)

## 0.3.1 (2015-05-02)

* PKCS8 private key info support (only unencrypted keys so far)

## 0.3.0 (2015-03-19)

* more detailed error messages (type certificate_failure modified)
* no longer Printf.printf debug messages
* error reporting: `Ok of certificate option | `Fail of certificate_failure
* fingerprint verification can work with None as host (useful for client authentication where host is not known upfront)
* API reshape: X509 is the only public module, X509.t is the abstract certificate

## 0.2.1 (2014-12-21)

* server_fingerprint authenticator which validates the server certificate based on a hash algorithm and (server_name * fingerprint) list instead of a set of trust anchors
* whitelist CAcert certificates (which do not include mandatory X.509v3 KeyUsage extension)

## 0.2.0 (2014-10-30)

* expose Certificate.cert_hostnames, wildcard_matches
* Certificate.verify_chain_of_trust and X509.authenticate both return now
  [ `Ok of certificate | `Fail of certificate_failure ], where [certificate] is the trust anchor

## 0.1.0 (2014-07-08)

* initial beta release
