_ Git - dnssec-prover/blob - src/lib.rs

   1 //! The DNS provides a single, global, hierarchical namespace with (when DNSSEC is used)
   2 //! cryptographic guarantees on all of its data.
   3 //!
   4 //! This makes it incredibly powerful for resolving human-readable names into arbitrary, secured
   5 //! data.
   6 //!
   7 //! Unlike TLS, this cryptographic security provides transferable proofs which can convince an
   8 //! offline device, using simple cryptographic primitives and a single root trusted key, of the
   9 //! validity of DNS data.
  10 //!
  11 //! This crate implements the creation and validation of such proofs, using the format from RFC
  12 //! 9102 to create transferable proofs of DNS entries.
  13 //!
  14 //! It is no-std (but requires `alloc`) and seeks to have minimal dependencies and a reasonably
  15 //! conservative MSRV policy, allowing it to be used in as many places as possible.
  16
  17 #![allow(deprecated)] // XXX
  18 #![deny(missing_docs)]
  19
  20 #![no_std]
  21 extern crate alloc;
  22
  23 use alloc::vec::Vec;
  24 use alloc::vec;
  25 use alloc::string::String;
  26 use alloc::borrow::ToOwned;
  27
  28 use ring::signature;
  29
  30 /// Gets the trusted root anchors
  31 ///
  32 /// These are available at <https://data.iana.org/root-anchors/root-anchors.xml>
  33 pub fn root_hints() -> Vec<DS> {
  34         #[allow(unused_mut)]
  35         let mut res = vec![DS {
  36                 name: ".".try_into().unwrap(), key_tag: 19036, alg: 8, digest_type: 2,
  37                 digest: hex_lit::hex!("49AAC11D7B6F6446702E54A1607371607A1A41855200FD2CE1CDDE32F24E8FB5").to_vec(),
  38         }, DS {
  39                 name: ".".try_into().unwrap(), key_tag: 20326, alg: 8, digest_type: 2,
  40                 digest: hex_lit::hex!("E06D44B80B8F1D39A95C0B0D7C65D08458E880409BBC683457104237C7F8EC8D").to_vec(),
  41         }];
  42         // In tests, add the trust anchor from RFC 9102
  43         #[cfg(test)]
  44         res.push(DS {
  45                 name: ".".try_into().unwrap(), key_tag: 47005, alg: 13, digest_type: 2,
  46                 digest: hex_lit::hex!("2eb6e9f2480126691594d649a5a613de3052e37861634641bb568746f2ffc4d4").to_vec(),
  47         });
  48         res
  49 }
  50
  51 /// A valid domain name.
  52 ///
  53 /// It must end with a ".", be no longer than 255 bytes, consist of only printable ASCII
  54 /// characters and each label may be no longer than 63 bytes.
  55 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
  56 pub struct Name(String);
  57 impl core::ops::Deref for Name {
  58         type Target = str;
  59         fn deref(&self) -> &str { &self.0 }
  60 }
  61 impl TryFrom<String> for Name {
  62         type Error = ();
  63         fn try_from(s: String) -> Result<Name, ()> {
  64                 if s.is_empty() { return Err(()); }
  65                 if *s.as_bytes().last().unwrap_or(&0) != b"."[0] { return Err(()); }
  66                 if s.len() > 255 { return Err(()); }
  67                 if s.chars().any(|c| !c.is_ascii_graphic() && c != '.' && c != '-') { return Err(()); }
  68                 for label in s.split(".") {
  69                         if label.len() > 63 { return Err(()); }
  70                 }
  71
  72                 Ok(Name(s))
  73         }
  74 }
  75 impl TryFrom<&str> for Name {
  76         type Error = ();
  77         fn try_from(s: &str) -> Result<Name, ()> {
  78                 Self::try_from(s.to_owned())
  79         }
  80 }
  81
  82 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
  83 /// A supported Resource Record
  84 ///
  85 /// Note that we only currently support a handful of RR types as needed to generate and validate
  86 /// TXT or TLSA record proofs.
  87 pub enum RR {
  88         /// A text resource record
  89         Txt(Txt),
  90         /// A TLS Certificate Association resource record
  91         TLSA(TLSA),
  92         /// A DNS (Public) Key resource record
  93         DnsKey(DnsKey),
  94         /// A Delegated Signer resource record
  95         DS(DS),
  96         /// A Resource Record Signature record
  97         RRSig(RRSig),
  98 }
  99 impl RR {
 100         /// Gets the name this record refers to.
 101         pub fn name(&self) -> &Name {
 102                 match self {
 103                         RR::Txt(rr) => &rr.name,
 104                         RR::TLSA(rr) => &rr.name,
 105                         RR::DnsKey(rr) => &rr.name,
 106                         RR::DS(rr) => &rr.name,
 107                         RR::RRSig(rr) => &rr.name,
 108                 }
 109         }
 110         fn ty(&self) -> u16 {
 111                 match self {
 112                         RR::Txt(_) => Txt::TYPE,
 113                         RR::TLSA(_) => TLSA::TYPE,
 114                         RR::DnsKey(_) => DnsKey::TYPE,
 115                         RR::DS(_) => DS::TYPE,
 116                         RR::RRSig(_) => RRSig::TYPE,
 117                 }
 118         }
 119         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
 120                 match self {
 121                         RR::Txt(rr) => StaticRecord::write_u16_len_prefixed_data(rr, out),
 122                         RR::TLSA(rr) => StaticRecord::write_u16_len_prefixed_data(rr, out),
 123                         RR::DnsKey(rr) => StaticRecord::write_u16_len_prefixed_data(rr, out),
 124                         RR::DS(rr) => StaticRecord::write_u16_len_prefixed_data(rr, out),
 125                         RR::RRSig(rr) => StaticRecord::write_u16_len_prefixed_data(rr, out),
 126                 }
 127         }
 128 }
 129 impl From<Txt> for RR { fn from(txt: Txt) -> RR { RR::Txt(txt) } }
 130 impl From<TLSA> for RR { fn from(tlsa: TLSA) -> RR { RR::TLSA(tlsa) } }
 131 impl From<DnsKey> for RR { fn from(dnskey: DnsKey) -> RR { RR::DnsKey(dnskey) } }
 132 impl From<DS> for RR { fn from(ds: DS) -> RR { RR::DS(ds) } }
 133 impl From<RRSig> for RR { fn from(rrsig: RRSig) -> RR { RR::RRSig(rrsig) } }
 134
 135 trait StaticRecord : Ord {
 136         // http://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml#dns-parameters-4
 137         const TYPE: u16;
 138         fn name(&self) -> &Name;
 139         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>);
 140 }
 141 /// A trait describing a resource record (including the [`RR`] enum).
 142 pub trait Record : Ord + {
 143         /// The resource record type, as maintained by IANA.
 144         ///
 145         /// Current assignments can be found at
 146         /// <http://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml#dns-parameters-4>
 147         fn ty(&self) -> u16;
 148         /// The name this record is at.
 149         fn name(&self) -> &Name;
 150         /// Writes the data of this record, prefixed by a u16 length, to the given `Vec`.
 151         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>);
 152 }
 153 impl<RR: StaticRecord> Record for RR {
 154         fn ty(&self) -> u16 { RR::TYPE }
 155         fn name(&self) -> &Name { RR::name(self) }
 156         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
 157                 RR::write_u16_len_prefixed_data(self, out)
 158         }
 159 }
 160 impl Record for RR {
 161         fn ty(&self) -> u16 { self.ty() }
 162         fn name(&self) -> &Name { self.name() }
 163         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
 164                 self.write_u16_len_prefixed_data(out)
 165         }
 166 }
 167
 168 fn read_u8(inp: &mut &[u8]) -> Result<u8, ()> {
 169         let res = *inp.get(0).ok_or(())?;
 170         *inp = &inp[1..];
 171         Ok(res)
 172 }
 173 fn read_u16(inp: &mut &[u8]) -> Result<u16, ()> {
 174         if inp.len() < 2 { return Err(()); }
 175         let mut bytes = [0; 2];
 176         bytes.copy_from_slice(&inp[..2]);
 177         *inp = &inp[2..];
 178         Ok(u16::from_be_bytes(bytes))
 179 }
 180 fn read_u32(inp: &mut &[u8]) -> Result<u32, ()> {
 181         if inp.len() < 4 { return Err(()); }
 182         let mut bytes = [0; 4];
 183         bytes.copy_from_slice(&inp[..4]);
 184         *inp = &inp[4..];
 185         Ok(u32::from_be_bytes(bytes))
 186 }
 187
 188 fn read_name(inp: &mut &[u8]) -> Result<Name, ()> {
 189         let mut name = String::with_capacity(1024);
 190         loop {
 191                 let len = read_u8(inp)? as usize;
 192                 if len == 0 {
 193                         if name.is_empty() { name += "."; }
 194                         break;
 195                 }
 196                 if inp.len() <= len { return Err(()); }
 197                 name += core::str::from_utf8(&inp[..len]).map_err(|_| ())?;
 198                 name += ".";
 199                 *inp = &inp[len..];
 200                 if name.len() > 1024 { return Err(()); }
 201         }
 202         Ok(name.try_into()?)
 203 }
 204
 205 trait Writer { fn write(&mut self, buf: &[u8]); }
 206 impl Writer for Vec<u8> { fn write(&mut self, buf: &[u8]) { self.extend_from_slice(buf); } }
 207 impl Writer for ring::digest::Context { fn write(&mut self, buf: &[u8]) { self.update(buf); } }
 208 fn write_name<W: Writer>(out: &mut W, name: &str) {
 209         let canonical_name = name.to_ascii_lowercase();
 210         if canonical_name == "." {
 211                 out.write(&[0]);
 212         } else {
 213                 for label in canonical_name.split(".") {
 214                         out.write(&(label.len() as u8).to_be_bytes());
 215                         out.write(label.as_bytes());
 216                 }
 217         }
 218 }
 219 fn name_len(name: &Name) -> u16 {
 220         if name.0 == "." {
 221                 1
 222         } else {
 223                 let mut res = 0;
 224                 for label in name.split(".") {
 225                         res += 1 + label.len();
 226                 }
 227                 res as u16
 228         }
 229 }
 230
 231 fn parse_rr(inp: &mut &[u8]) -> Result<RR, ()> {
 232         let name = read_name(inp)?;
 233         let ty = read_u16(inp)?;
 234         let class = read_u16(inp)?;
 235         if class != 1 { return Err(()); } // We only support the INternet
 236         let _ttl = read_u32(inp)?;
 237         let data_len = read_u16(inp)? as usize;
 238         if inp.len() < data_len { return Err(()); }
 239         let mut data = &inp[..data_len];
 240         *inp = &inp[data_len..];
 241
 242         match ty {
 243                 Txt::TYPE => {
 244                         let mut parsed_data = Vec::with_capacity(data_len - 1);
 245                         while !data.is_empty() {
 246                                 let len = read_u8(&mut data)? as usize;
 247                                 if data.len() < len { return Err(()); }
 248                                 parsed_data.extend_from_slice(&data[..len]);
 249                                 data = &data[len..];
 250                         }
 251                         Ok(RR::Txt(Txt { name, data: parsed_data }))
 252                 }
 253                 TLSA::TYPE => {
 254                         if data_len <= 3 { return Err(()); }
 255                         Ok(RR::TLSA(TLSA {
 256                                 name, cert_usage: read_u8(&mut data)?, selector: read_u8(&mut data)?,
 257                                 data_ty: read_u8(&mut data)?, data: data.to_vec(),
 258                         }))
 259                 },
 260                 DnsKey::TYPE => {
 261                         Ok(RR::DnsKey(DnsKey {
 262                                 name, flags: read_u16(&mut data)?, protocol: read_u8(&mut data)?,
 263                                 alg: read_u8(&mut data)?, pubkey: data.to_vec(),
 264                         }))
 265                 },
 266                 DS::TYPE => {
 267                         Ok(RR::DS(DS {
 268                                 name, key_tag: read_u16(&mut data)?, alg: read_u8(&mut data)?,
 269                                 digest_type: read_u8(&mut data)?, digest: data.to_vec(),
 270                         }))
 271                 },
 272                 RRSig::TYPE => {
 273                         Ok(RR::RRSig(RRSig {
 274                                 name, ty: read_u16(&mut data)?, alg: read_u8(&mut data)?,
 275                                 labels: read_u8(&mut data)?, orig_ttl: read_u32(&mut data)?,
 276                                 expiration: read_u32(&mut data)?, inception: read_u32(&mut data)?,
 277                                 key_tag: read_u16(&mut data)?, key_name: read_name(&mut data)?,
 278                                 signature: data.to_vec(),
 279                         }))
 280                 },
 281                 _ => Err(()),
 282         }
 283 }
 284 /// Parse a stream of [`RR`]s from the format described in [RFC 9102](https://www.rfc-editor.org/rfc/rfc9102.html).
 285 ///
 286 /// Note that this is only the series of `AuthenticationChain` records, and does not read the
 287 /// `ExtSupportLifetime` field at the start of a `DnssecChainExtension`.
 288 pub fn parse_rr_stream(mut inp: &[u8]) -> Result<Vec<RR>, ()> {
 289         let mut res = Vec::with_capacity(32);
 290         while !inp.is_empty() {
 291                 res.push(parse_rr(&mut inp)?);
 292         }
 293         Ok(res)
 294 }
 295
 296 /// Writes the given resource record in its wire encoding to the given `Vec`.
 297 ///
 298 /// An [RFC 9102](https://www.rfc-editor.org/rfc/rfc9102.html) `AuthenticationChain` is simply a
 299 /// series of such records with no additional bytes in between.
 300 pub fn write_rr<RR: Record>(rr: &RR, ttl: u32, out: &mut Vec<u8>) {
 301         write_name(out, rr.name());
 302         out.extend_from_slice(&rr.ty().to_be_bytes());
 303         out.extend_from_slice(&1u16.to_be_bytes()); // The INternet class
 304         out.extend_from_slice(&ttl.to_be_bytes());
 305         rr.write_u16_len_prefixed_data(out);
 306 }
 307
 308 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)] // TODO: ord is wrong cause need to consider len first, maybe
 309 /// A text resource record, containing arbitrary text data
 310 pub struct Txt {
 311         /// The name this record is at.
 312         pub name: Name,
 313         /// The text record itself.
 314         ///
 315         /// While this is generally UTF-8-valid, there is no specific requirement that it be, and thus
 316         /// is an arbitrary series of bytes here.
 317         data: Vec<u8>,
 318 }
 319 impl StaticRecord for Txt {
 320         const TYPE: u16 = 16;
 321         fn name(&self) -> &Name { &self.name }
 322         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
 323                 let len = (self.data.len() + self.data.len() / 255 + 1) as u16;
 324                 out.extend_from_slice(&len.to_be_bytes());
 325
 326                 let mut data_write = &self.data[..];
 327                 out.extend_from_slice(&[data_write.len().try_into().unwrap_or(255)]);
 328                 while !data_write.is_empty() {
 329                         let split_pos = core::cmp::min(255, data_write.len());
 330                         out.extend_from_slice(&data_write[..split_pos]);
 331                         data_write = &data_write[split_pos..];
 332                         if !data_write.is_empty() {
 333                                 out.extend_from_slice(&[data_write.len().try_into().unwrap_or(255)]);
 334                         }
 335                 }
 336         }
 337 }
 338
 339 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
 340 /// A TLS Certificate Association resource record containing information about the TLS certificate
 341 /// which should be expected when communicating with the host at the given name.
 342 ///
 343 /// See <https://en.wikipedia.org/wiki/DNS-based_Authentication_of_Named_Entities#TLSA_RR> for more
 344 /// info.
 345 pub struct TLSA {
 346         /// The name this record is at.
 347         pub name: Name,
 348         /// The type of constraint on the TLS certificate(s) used which should be enforced by this
 349         /// record.
 350         pub cert_usage: u8,
 351         /// Whether to match on the full certificate, or only the public key.
 352         pub selector: u8,
 353         /// The type of data included which is used to match the TLS certificate(s).
 354         pub data_ty: u8,
 355         /// The certificate data or hash of the certificate data itself.
 356         pub data: Vec<u8>,
 357 }
 358 impl StaticRecord for TLSA {
 359         const TYPE: u16 = 52;
 360         fn name(&self) -> &Name { &self.name }
 361         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
 362                 let len = 3 + self.data.len();
 363                 out.extend_from_slice(&(len as u16).to_be_bytes());
 364                 out.extend_from_slice(&[self.cert_usage, self.selector, self.data_ty]);
 365                 out.extend_from_slice(&self.data);
 366         }
 367 }
 368
 369 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
 370 /// A public key resource record which can be used to validate [`RRSig`]s.
 371 pub struct DnsKey {
 372         /// The name this record is at.
 373         pub name: Name,
 374         /// Flags which constrain the usage of this public key.
 375         pub flags: u16,
 376         /// The protocol this key is used for (protocol `3` is DNSSEC).
 377         pub protocol: u8,
 378         /// The algorithm which this public key uses to sign data.
 379         pub alg: u8,
 380         /// The public key itself.
 381         pub pubkey: Vec<u8>,
 382 }
 383 impl StaticRecord for DnsKey {
 384         const TYPE: u16 = 48;
 385         fn name(&self) -> &Name { &self.name }
 386         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
 387                 let len = 2 + 1 + 1 + self.pubkey.len();
 388                 out.extend_from_slice(&(len as u16).to_be_bytes());
 389                 out.extend_from_slice(&self.flags.to_be_bytes());
 390                 out.extend_from_slice(&self.protocol.to_be_bytes());
 391                 out.extend_from_slice(&self.alg.to_be_bytes());
 392                 out.extend_from_slice(&self.pubkey);
 393         }
 394 }
 395 impl DnsKey {
 396         /// A short (non-cryptographic) digest which can be used to refer to this [`DnsKey`].
 397         pub fn key_tag(&self) -> u16 {
 398                 let mut res = u32::from(self.flags);
 399                 res += u32::from(self.protocol) << 8;
 400                 res += u32::from(self.alg);
 401                 for (idx, b) in self.pubkey.iter().enumerate() {
 402                         if idx % 2 == 0 {
 403                                 res += u32::from(*b) << 8;
 404                         } else {
 405                                 res += u32::from(*b);
 406                         }
 407                 }
 408                 res += (res >> 16) & 0xffff;
 409                 (res & 0xffff) as u16
 410         }
 411 }
 412
 413 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
 414 /// A Delegation Signer resource record which indicates that some alternative [`DnsKey`] can sign
 415 /// for records in the zone which matches [`DS::name`].
 416 pub struct DS {
 417         /// The name this record is at.
 418         ///
 419         /// This is also the zone that a [`DnsKey`] which matches the [`Self::digest`] can sign for.
 420         pub name: Name,
 421         /// A short tag which describes the matching [`DnsKey`].
 422         ///
 423         /// This matches the [`DnsKey::key_tag`] for the [`DnsKey`] which is referred to by this
 424         /// [`DS`].
 425         pub key_tag: u16,
 426         /// The algorithm which the [`DnsKey`] referred to by this [`DS`] uses.
 427         ///
 428         /// This matches the [`DnsKey::alg`] field in the referred-to [`DnsKey`].
 429         pub alg: u8,
 430         /// The type of digest used to hash the referred-to [`DnsKey`].
 431         pub digest_type: u8,
 432         /// The digest itself.
 433         pub digest: Vec<u8>,
 434 }
 435 impl StaticRecord for DS {
 436         const TYPE: u16 = 43;
 437         fn name(&self) -> &Name { &self.name }
 438         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
 439                 let len = 2 + 1 + 1 + self.digest.len();
 440                 out.extend_from_slice(&(len as u16).to_be_bytes());
 441                 out.extend_from_slice(&self.key_tag.to_be_bytes());
 442                 out.extend_from_slice(&self.alg.to_be_bytes());
 443                 out.extend_from_slice(&self.digest_type.to_be_bytes());
 444                 out.extend_from_slice(&self.digest);
 445         }
 446 }
 447
 448 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
 449 /// A Resource Record (set) Signature resource record. This contains a signature over all the
 450 /// resources records of the given type at the given name.
 451 pub struct RRSig {
 452         /// The name this record is at.
 453         ///
 454         /// This is also the name of any records which this signature is covering (ignoring wildcards).
 455         pub name: Name,
 456         /// The resource record type which this [`RRSig`] is signing.
 457         ///
 458         /// All resources records of this type at the same name as [`Self::name`] must be signed by
 459         /// this [`RRSig`].
 460         pub ty: u16,
 461         /// The algorithm which is being used to sign.
 462         ///
 463         /// This must match the [`DnsKey::alg`] field in the [`DnsKey`] being used to sign.
 464         pub alg: u8,
 465         /// The number of labels in the name of the records that this signature is signing.
 466         // TODO: Describe this better in terms of wildcards
 467         pub labels: u8,
 468         /// The TTL of the records which this [`RRSig`] is signing.
 469         pub orig_ttl: u32,
 470         /// The expiration (as a UNIX timestamp) of this signature.
 471         pub expiration: u32,
 472         /// The time (as a UNIX timestamp) at which this signature becomes valid.
 473         pub inception: u32,
 474         /// A short tag which describes the matching [`DnsKey`].
 475         ///
 476         /// This matches the [`DnsKey::key_tag`] for the [`DnsKey`] which created this signature.
 477         pub key_tag: u16,
 478         /// The [`DnsKey::name`] in the [`DnsKey`] which created this signature.
 479         ///
 480         /// This must be a parent of the [`Self::name`].
 481         pub key_name: Name,
 482         /// The signature itself.
 483         pub signature: Vec<u8>,
 484 }
 485 impl StaticRecord for RRSig {
 486         const TYPE: u16 = 46;
 487         fn name(&self) -> &Name { &self.name }
 488         fn write_u16_len_prefixed_data(&self, out: &mut Vec<u8>) {
 489                 let len = 2 + 1 + 1 + 4*3 + 2 + name_len(&self.key_name) + self.signature.len() as u16;
 490                 out.extend_from_slice(&len.to_be_bytes());
 491                 out.extend_from_slice(&self.ty.to_be_bytes());
 492                 out.extend_from_slice(&self.alg.to_be_bytes());
 493                 out.extend_from_slice(&self.labels.to_be_bytes());
 494                 out.extend_from_slice(&self.orig_ttl.to_be_bytes());
 495                 out.extend_from_slice(&self.expiration.to_be_bytes());
 496                 out.extend_from_slice(&self.inception.to_be_bytes());
 497                 out.extend_from_slice(&self.key_tag.to_be_bytes());
 498                 write_name(out, &self.key_name);
 499                 out.extend_from_slice(&self.signature);
 500         }
 501 }
 502
 503 #[derive(Debug, PartialEq)]
 504 /// An error when validating DNSSEC signatures or other data
 505 pub enum ValidationError {
 506         /// An algorithm used in signing was not supported.
 507         ///
 508         /// In general DNS usage the resulting data should be used anyway, as we were able to verify
 509         /// that a zone wished to use the unsupported algorithm.
 510         ///
 511         /// However, in cases where signing is mandatory, this can be treated as an error.
 512         UnsupportedAlgorithm,
 513         /// The provided data was invalid or signatures did not validate.
 514         Invalid,
 515 }
 516
 517 fn bytes_to_rsa_pk<'a>(pubkey: &'a [u8])
 518 -> Result<signature::RsaPublicKeyComponents<&'a [u8]>, ValidationError> {
 519         if pubkey.len() <= 3 { return Err(ValidationError::Invalid); }
 520
 521         let mut pos = 0;
 522         let exponent_length;
 523         if pubkey[0] == 0 {
 524                 exponent_length = ((pubkey[1] as usize) << 8) | (pubkey[2] as usize);
 525                 pos += 3;
 526         } else {
 527                 exponent_length = pubkey[0] as usize;
 528                 pos += 1;
 529         }
 530
 531         if pubkey.len() <= pos + exponent_length { return Err(ValidationError::Invalid); }
 532         Ok(signature::RsaPublicKeyComponents {
 533                 n: &pubkey[pos + exponent_length..],
 534                 e: &pubkey[pos..pos + exponent_length]
 535         })
 536 }
 537
 538 // TODO: return the validity period
 539 fn verify_rrsig<'a, RR: Record, Keys>(sig: &RRSig, dnskeys: Keys, mut records: Vec<&RR>)
 540 -> Result<(), ValidationError>
 541 where Keys: IntoIterator<Item = &'a DnsKey> {
 542         for record in records.iter() {
 543                 if sig.ty != record.ty() { return Err(ValidationError::Invalid); }
 544         }
 545         for dnskey in dnskeys.into_iter() {
 546                 if dnskey.key_tag() == sig.key_tag {
 547                         // Protocol must be 3, otherwise its not DNSSEC
 548                         if dnskey.protocol != 3 { continue; }
 549                         // The ZONE flag must be set if we're going to validate RRs with this key.
 550                         if dnskey.flags & 0b1_0000_0000 == 0 { continue; }
 551                         if dnskey.alg != sig.alg { continue; }
 552
 553                         // TODO: Check orig_ttl somehow?
 554
 555                         let mut signed_data = Vec::with_capacity(2048);
 556                         signed_data.extend_from_slice(&sig.ty.to_be_bytes());
 557                         signed_data.extend_from_slice(&sig.alg.to_be_bytes());
 558                         signed_data.extend_from_slice(&sig.labels.to_be_bytes()); // Check this somehow?
 559                         signed_data.extend_from_slice(&sig.orig_ttl.to_be_bytes());
 560                         signed_data.extend_from_slice(&sig.expiration.to_be_bytes()); // Return this and inception
 561                         signed_data.extend_from_slice(&sig.inception.to_be_bytes());
 562                         signed_data.extend_from_slice(&sig.key_tag.to_be_bytes());
 563                         write_name(&mut signed_data, &sig.key_name);
 564
 565                         records.sort();
 566
 567                         for record in records.iter() {
 568                                 // TODO: Handle wildcards
 569                                 write_name(&mut signed_data, record.name());
 570                                 signed_data.extend_from_slice(&record.ty().to_be_bytes());
 571                                 signed_data.extend_from_slice(&1u16.to_be_bytes()); // The INternet class
 572                                 signed_data.extend_from_slice(&sig.orig_ttl.to_be_bytes());
 573                                 record.write_u16_len_prefixed_data(&mut signed_data);
 574                         }
 575
 576                         match sig.alg {
 577                                 8|10 => {
 578                                         let alg = if sig.alg == 8 {
 579                                                 &signature::RSA_PKCS1_1024_8192_SHA256_FOR_LEGACY_USE_ONLY
 580                                         } else {
 581                                                 &signature::RSA_PKCS1_1024_8192_SHA512_FOR_LEGACY_USE_ONLY
 582                                         };
 583                                         bytes_to_rsa_pk(&dnskey.pubkey)?
 584                                                 .verify(alg, &signed_data, &sig.signature)
 585                                                 .map_err(|_| ValidationError::Invalid)?;
 586                                 },
 587                                 13|14 => {
 588                                         let alg = if sig.alg == 13 {
 589                                                 &signature::ECDSA_P256_SHA256_FIXED
 590                                         } else {
 591                                                 &signature::ECDSA_P384_SHA384_FIXED
 592                                         };
 593
 594                                         // Add 0x4 identifier to the ECDSA pubkey as expected by ring.
 595                                         let mut key = Vec::with_capacity(dnskey.pubkey.len() + 1);
 596                                         key.push(0x4);
 597                                         key.extend_from_slice(&dnskey.pubkey);
 598
 599                                         signature::UnparsedPublicKey::new(alg, &key)
 600                                                 .verify(&signed_data, &sig.signature)
 601                                                 .map_err(|_| ValidationError::Invalid)?;
 602                                 },
 603                                 15 => {
 604                                         signature::UnparsedPublicKey::new(&signature::ED25519, &dnskey.pubkey)
 605                                                 .verify(&signed_data, &sig.signature)
 606                                                 .map_err(|_| ValidationError::Invalid)?;
 607                                 },
 608                                 _ => return Err(ValidationError::UnsupportedAlgorithm),
 609                         }
 610
 611                         return Ok(());
 612                 }
 613         }
 614         Err(ValidationError::Invalid)
 615 }
 616
 617 fn verify_dnskey_rrsig<'a, T, I>(sig: &RRSig, dses: T, records: Vec<&DnsKey>)
 618 -> Result<(), ValidationError>
 619 where T: IntoIterator<IntoIter = I>, I: Iterator<Item = &'a DS> + Clone {
 620         let mut validated_dnskeys = Vec::with_capacity(records.len());
 621         let dses = dses.into_iter();
 622
 623         let mut had_known_digest_type = false;
 624         let mut had_ds = false;
 625         for ds in dses.clone() {
 626                 had_ds = true;
 627                 if ds.digest_type == 2 || ds.digest_type == 4 {
 628                         had_known_digest_type = true;
 629                         break;
 630                 }
 631         }
 632         if !had_ds { return Err(ValidationError::Invalid); }
 633         if !had_known_digest_type { return Err(ValidationError::UnsupportedAlgorithm); }
 634
 635         for dnskey in records.iter() {
 636                 for ds in dses.clone() {
 637                         if ds.digest_type != 2 && ds.digest_type != 4 { continue; }
 638                         if ds.alg != dnskey.alg { continue; }
 639                         if dnskey.key_tag() == ds.key_tag {
 640                                 let alg = match ds.digest_type {
 641                                         2 => &ring::digest::SHA256,
 642                                         4 => &ring::digest::SHA384,
 643                                         _ => continue,
 644                                 };
 645                                 let mut ctx = ring::digest::Context::new(alg);
 646                                 write_name(&mut ctx, &dnskey.name);
 647                                 ctx.update(&dnskey.flags.to_be_bytes());
 648                                 ctx.update(&dnskey.protocol.to_be_bytes());
 649                                 ctx.update(&dnskey.alg.to_be_bytes());
 650                                 ctx.update(&dnskey.pubkey);
 651                                 let hash = ctx.finish();
 652                                 if hash.as_ref() == &ds.digest {
 653                                         validated_dnskeys.push(*dnskey);
 654                                         break;
 655                                 }
 656                         }
 657                 }
 658         }
 659         verify_rrsig(sig, validated_dnskeys.iter().map(|k| *k), records)
 660 }
 661
 662 /// Verifies the given set of resource records.
 663 ///
 664 /// Given a set of arbitrary records, this attempts to validate DNSSEC data from the [`root_hints`]
 665 /// through to any supported non-DNSSEC record types.
 666 ///
 667 /// All records which could be validated are returned, though if an error is found validating any
 668 /// contained record, only `Err` will be returned.
 669 pub fn verify_rr_stream<'a>(inp: &'a [RR]) -> Result<Vec<&'a RR>, ValidationError> {
 670         let mut zone = ".";
 671         let mut res = Vec::new();
 672         let mut pending_ds_sets = Vec::with_capacity(1);
 673         'next_zone: while zone == "." || !pending_ds_sets.is_empty() {
 674                 let mut found_unsupported_alg = false;
 675                 let next_ds_set;
 676                 if let Some((next_zone, ds_set)) = pending_ds_sets.pop() {
 677                         next_ds_set = Some(ds_set);
 678                         zone = next_zone;
 679                 } else {
 680                         debug_assert_eq!(zone, ".");
 681                         next_ds_set = None;
 682                 }
 683
 684                 for rrsig in inp.iter()
 685                         .filter_map(|rr| if let RR::RRSig(sig) = rr { Some(sig) } else { None })
 686                         .filter(|rrsig| rrsig.name.0 == zone && rrsig.ty == DnsKey::TYPE)
 687                 {
 688                         let dnskeys = inp.iter()
 689                                 .filter_map(|rr| if let RR::DnsKey(dnskey) = rr { Some(dnskey) } else { None })
 690                                 .filter(move |dnskey| dnskey.name.0 == zone);
 691                         let dnskeys_verified = if zone == "." {
 692                                 verify_dnskey_rrsig(rrsig, &root_hints(), dnskeys.clone().collect())
 693                         } else {
 694                                 debug_assert!(next_ds_set.is_some());
 695                                 if next_ds_set.is_none() { break 'next_zone; }
 696                                 verify_dnskey_rrsig(rrsig, next_ds_set.clone().unwrap(), dnskeys.clone().collect())
 697                         };
 698                         if dnskeys_verified.is_ok() {
 699                                 for rrsig in inp.iter()
 700                                         .filter_map(|rr| if let RR::RRSig(sig) = rr { Some(sig) } else { None })
 701                                         .filter(move |rrsig| rrsig.key_name.0 == zone && rrsig.name.0 != zone)
 702                                 {
 703                                         if !rrsig.name.ends_with(zone) { return Err(ValidationError::Invalid); }
 704                                         let signed_records = inp.iter()
 705                                                 .filter(|rr| rr.name() == &rrsig.name && rr.ty() == rrsig.ty);
 706                                         verify_rrsig(rrsig, dnskeys.clone(), signed_records.clone().collect())?;
 707                                         match rrsig.ty {
 708                                                 // RRSigs shouldn't cover child `DnsKey`s or other `RRSig`s
 709                                                 RRSig::TYPE|DnsKey::TYPE => return Err(ValidationError::Invalid),
 710                                                 DS::TYPE => {
 711                                                         if !pending_ds_sets.iter().any(|(pending_zone, _)| pending_zone == &rrsig.name.0) {
 712                                                                 pending_ds_sets.push((
 713                                                                         &rrsig.name,
 714                                                                         signed_records.filter_map(|rr|
 715                                                                                 if let RR::DS(ds) = rr { Some(ds) }
 716                                                                                 else { debug_assert!(false, "We already filtered by type"); None })
 717                                                                 ));
 718                                                         }
 719                                                 },
 720                                                 _ => {
 721                                                         for record in signed_records {
 722                                                                 if !res.contains(&record) { res.push(record); }
 723                                                         }
 724                                                 },
 725                                         }
 726                                 }
 727                                 continue 'next_zone;
 728                         } else if dnskeys_verified == Err(ValidationError::UnsupportedAlgorithm) {
 729                                 // There may be redundant signatures by different keys, where one we don't supprt
 730                                 // and another we do. Ignore ones we don't support, but if there are no more,
 731                                 // return UnsupportedAlgorithm
 732                                 found_unsupported_alg = true;
 733                         } else {
 734                                 // We don't explicitly handle invalid signatures here, instead we move on to the
 735                                 // next RRSig (if there is one) and return `Invalid` if no `RRSig`s match.
 736                         }
 737                 }
 738                 // No RRSigs were able to verify our DnsKey set
 739                 if found_unsupported_alg {
 740                         return Err(ValidationError::UnsupportedAlgorithm);
 741                 } else {
 742                         return Err(ValidationError::Invalid);
 743                 }
 744         }
 745         if res.is_empty() { Err(ValidationError::Invalid) }
 746         else { Ok(res) }
 747 }
 748
 749 #[cfg(test)]
 750 mod tests {
 751         use super::*;
 752
 753         use hex_conservative::FromHex;
 754         use rand::seq::SliceRandom;
 755
 756         fn root_dnskey() -> (Vec<DnsKey>, Vec<RR>) {
 757                 let dnskeys = vec![DnsKey {
 758                         name: ".".try_into().unwrap(), flags: 256, protocol: 3, alg: 8,
 759                         pubkey: base64::decode("AwEAAentCcIEndLh2QSK+pHFq/PkKCwioxt75d7qNOUuTPMo0Fcte/NbwDPbocvbZ/eNb5RV/xQdapaJASQ/oDLsqzD0H1+JkHNuuKc2JLtpMxg4glSE4CnRXT2CnFTW5IwOREL+zeqZHy68OXy5ngW5KALbevRYRg/q2qFezRtCSQ0knmyPwgFsghVYLKwi116oxwEU5yZ6W7npWMxt5Z+Qs8diPNWrS5aXLgJtrWUGIIuFfuZwXYziGRP/z3o1EfMo9zZU19KLopkoLXX7Ls/diCXdSEdJXTtFA8w0/OKQviuJebfKscoElCTswukVZ1VX5gbaFEo2xWhHJ9Uo63wYaTk=").unwrap(),
 760                 }, DnsKey {
 761                         name: ".".try_into().unwrap(), flags: 257, protocol: 3, alg: 8,
 762                         pubkey: base64::decode("AwEAAaz/tAm8yTn4Mfeh5eyI96WSVexTBAvkMgJzkKTOiW1vkIbzxeF3+/4RgWOq7HrxRixHlFlExOLAJr5emLvN7SWXgnLh4+B5xQlNVz8Og8kvArMtNROxVQuCaSnIDdD5LKyWbRd2n9WGe2R8PzgCmr3EgVLrjyBxWezF0jLHwVN8efS3rCj/EWgvIWgb9tarpVUDK/b58Da+sqqls3eNbuv7pr+eoZG+SrDK6nWeL3c6H5Apxz7LjVc1uTIdsIXxuOLYA4/ilBmSVIzuDWfdRUfhHdY6+cn8HFRm+2hM8AnXGXws9555KrUB5qihylGa8subX2Nn6UwNR1AkUTV74bU=").unwrap(),
 763                 }];
 764                 let dnskey_rrsig = RRSig {
 765                         name: ".".try_into().unwrap(), ty: DnsKey::TYPE, alg: 8, labels: 0, orig_ttl: 172800,
 766                         expiration: 1708473600, inception: 1706659200, key_tag: 20326, key_name: ".".try_into().unwrap(),
 767                         signature: base64::decode("ZO8LbjtwAiVkkBzOnGbiI/3ilGUPmmJpagsLSBVbIZRG6o/8a+hUZpIPTvk5ERZ1rAW4x0YxKAU8qtaHQpKIp3qYA6u97DYytVD7RdtXKHmGYAvR6QbD5eVTkCw1Sz705rJxbwt6+YM5OBweSUAy5Glo6JSQPDQwRDwj/bV2fLRhJbvfsBgxqaXJA0SaE/ceyvK8gB2NIaguTJNrztr2TENrHxi86OKOuHYDHthOW0TFoPfr19qj/P2eEC6dYniTVovUwHT7e+Hqrb05dJF4mI4ZjaIb5mFf8i5RehT1aRlnb3CLiwJ01bEjrRBo3xUn5I3PkCnglHhx3EvkO73OzA==").unwrap(),
 768                 };
 769                 let root_hints = root_hints();
 770                 verify_dnskey_rrsig(&dnskey_rrsig, &root_hints, dnskeys.iter().collect()).unwrap();
 771                 let rrs = vec![dnskeys[0].clone().into(), dnskeys[1].clone().into(), dnskey_rrsig.into()];
 772                 (dnskeys, rrs)
 773         }
 774
 775         fn com_dnskey() -> (Vec<DnsKey>, Vec<RR>) {
 776                 let root_dnskeys = root_dnskey().0;
 777                 let mut com_ds = vec![DS {
 778                         name: "com.".try_into().unwrap(), key_tag: 19718, alg: 13, digest_type: 2,
 779                         digest: Vec::from_hex("8ACBB0CD28F41250A80A491389424D341522D946B0DA0C0291F2D3D771D7805A").unwrap(),
 780                 }];
 781                 let ds_rrsig = RRSig {
 782                         name: "com.".try_into().unwrap(), ty: DS::TYPE, alg: 8, labels: 1, orig_ttl: 86400,
 783                         expiration: 1708189200, inception: 1707062400, key_tag: 30903, key_name: ".".try_into().unwrap(),
 784                         signature: base64::decode("vwMOBBwqRBdlmGZB+0FKfyMSignEtpYW9sD4TzPW2E+wdbF7O7epR5cmKmvcv0RUJdM0dGC/QmhCfgf/yqw1Xp7TpmPaYzaruW70hjGXZJO2nY3G6stUVe4S7lM2CzHL7nbbpaB5B+iSu6Ua9dZ+nyKrxfB7855HBLCLrHrkMGxWQiEPTallXXS8tEM1Y2XrsuzAQu2vZ2D2ClhFspFbPwwOdw+G6+NsZ8PnIfTkCj6DuKcgbdxjmGaYmw/6hVt9OU3kGCOBaJaEy4LrD8Kwzfu4S7axMwTKP4y4c5Y/E4k/mVAW0cuUtv549HaDfD2V0CvW1bDl6PqRkOiVsqM/lA==").unwrap(),
 785                 };
 786                 verify_rrsig(&ds_rrsig, &root_dnskeys, com_ds.iter().collect()).unwrap();
 787                 let dnskeys = vec![DnsKey {
 788                         name: "com.".try_into().unwrap(), flags: 256, protocol: 3, alg: 13,
 789                         pubkey: base64::decode("5i9qjJgyH+9MBz7VO269/srLQB/xRRllyUoVq8oLBZshPe4CGzDSFGnXAM3L/QPzB9ULpJuuy7jcxmBZ5Ebo7A==").unwrap(),
 790                 }, DnsKey {
 791                         name: "com.".try_into().unwrap(), flags: 257, protocol: 3, alg: 13,
 792                         pubkey: base64::decode("tx8EZRAd2+K/DJRV0S+hbBzaRPS/G6JVNBitHzqpsGlz8huE61Ms9ANe6NSDLKJtiTBqfTJWDAywEp1FCsEINQ==").unwrap(),
 793                 }];
 794                 let dnskey_rrsig = RRSig {
 795                         name: "com.".try_into().unwrap(), ty: DnsKey::TYPE, alg: 13, labels: 1, orig_ttl: 86400,
 796                         expiration: 1707750155, inception: 1706453855, key_tag: 19718, key_name: "com.".try_into().unwrap(),
 797                         signature: base64::decode("ZFGChM7QfJt0QSqVWerWnG5pMjpL1pXyJAmuHe8dHI/olmaNCxm+mqNHv9i3AploFY6JoNtiHmeBiC6zuFj/ZQ==").unwrap(),
 798                 };
 799                 verify_dnskey_rrsig(&dnskey_rrsig, &com_ds, dnskeys.iter().collect()).unwrap();
 800                 let rrs = vec![com_ds.pop().unwrap().into(), ds_rrsig.into(),
 801                         dnskeys[0].clone().into(), dnskeys[1].clone().into(), dnskey_rrsig.into()];
 802                 (dnskeys, rrs)
 803         }
 804
 805         fn mattcorallo_dnskey() -> (Vec<DnsKey>, Vec<RR>) {
 806                 let com_dnskeys = com_dnskey().0;
 807                 let mut mattcorallo_ds = vec![DS {
 808                         name: "mattcorallo.com.".try_into().unwrap(), key_tag: 25630, alg: 13, digest_type: 2,
 809                         digest: Vec::from_hex("DC608CA62BE89B3B9DB1593F9A59930D24FBA79D486E19C88A7792711EC00735").unwrap(),
 810                 }];
 811                 let ds_rrsig = RRSig {
 812                         name: "mattcorallo.com.".try_into().unwrap(), ty: DS::TYPE, alg: 13, labels: 2, orig_ttl: 86400,
 813                         expiration: 1707631252, inception: 1707022252, key_tag: 4534, key_name: "com.".try_into().unwrap(),
 814                         signature: base64::decode("M7Fk+CjfLz6hRsY5iSuw5bwc2OqlS3XtKH8FDs7lcbhEiR63n+DzOF0I8L+3k06SXFnE89uuofQECzWmAyef6Q==").unwrap(),
 815                 };
 816                 verify_rrsig(&ds_rrsig, &com_dnskeys, mattcorallo_ds.iter().collect()).unwrap();
 817                 let dnskeys = vec![DnsKey {
 818                         name: "mattcorallo.com.".try_into().unwrap(), flags: 257, protocol: 3, alg: 13,
 819                         pubkey: base64::decode("8BP51Etiu4V6cHvGCYqwNqCip4pvHChjEgkgG4zpdDvO9YRcTGuV/p71hAUut2/qEdxqXfUOT/082BJ/Z089DA==").unwrap(),
 820                 }, DnsKey {
 821                         name: "mattcorallo.com.".try_into().unwrap(), flags: 256, protocol: 3, alg: 13,
 822                         pubkey: base64::decode("AhUlQ8qk7413R0m4zKfTDHb/FQRlKag+ncGXxNxT+qTzSZTb9E5IGjo9VCEp6+IMqqpkd4GrXpN9AzDvlcU9Ig==").unwrap(),
 823                 }];
 824                 let dnskey_rrsig = RRSig {
 825                         name: "mattcorallo.com.".try_into().unwrap(), ty: DnsKey::TYPE, alg: 13, labels: 2, orig_ttl: 604800,
 826                         expiration: 1708278650, inception: 1707063650, key_tag: 25630, key_name: "mattcorallo.com.".try_into().unwrap(),
 827                         signature: base64::decode("nyVDwG+la8d5dyWgB7m+H3BQwCvTWLQ/kAqNruMzdLmn9B3VC9u/rvM/ortEu0WPbA1FZWJbRKpF1Ohkj3ltNw==").unwrap(),
 828                 };
 829                 verify_dnskey_rrsig(&dnskey_rrsig, &mattcorallo_ds, dnskeys.iter().collect()).unwrap();
 830                 let rrs = vec![mattcorallo_ds.pop().unwrap().into(), ds_rrsig.into(),
 831                         dnskeys[0].clone().into(), dnskeys[1].clone().into(), dnskey_rrsig.into()];
 832                 (dnskeys, rrs)
 833         }
 834
 835         fn mattcorallo_txt_record() -> (Txt, RRSig) {
 836                 let txt_resp = Txt {
 837                         name: "matt.user._bitcoin-payment.mattcorallo.com.".try_into().unwrap(),
 838                         data: "bitcoin:?b12=lno1qsgqmqvgm96frzdg8m0gc6nzeqffvzsqzrxqy32afmr3jn9ggkwg3egfwch2hy0l6jut6vfd8vpsc3h89l6u3dm4q2d6nuamav3w27xvdmv3lpgklhg7l5teypqz9l53hj7zvuaenh34xqsz2sa967yzqkylfu9xtcd5ymcmfp32h083e805y7jfd236w9afhavqqvl8uyma7x77yun4ehe9pnhu2gekjguexmxpqjcr2j822xr7q34p078gzslf9wpwz5y57alxu99s0z2ql0kfqvwhzycqq45ehh58xnfpuek80hw6spvwrvttjrrq9pphh0dpydh06qqspp5uq4gpyt6n9mwexde44qv7lstzzq60nr40ff38u27un6y53aypmx0p4qruk2tf9mjwqlhxak4znvna5y".to_owned().into_bytes(),
 839                 };
 840                 let txt_rrsig = RRSig {
 841                         name: "matt.user._bitcoin-payment.mattcorallo.com.".try_into().unwrap(),
 842                         ty: Txt::TYPE, alg: 13, labels: 5, orig_ttl: 3600, expiration: 1708123318,
 843                         inception: 1706908318, key_tag: 47959, key_name: "mattcorallo.com.".try_into().unwrap(),
 844                         signature: base64::decode("mgU6iwyMWO0w9nj2Gmt1+RmaIJIU3KO7DWVZiCD1bmU9e9zNefXCtnWOC2HtwjUsn/QYkWluvuSfYpBrt1IjpQ==").unwrap(),
 845                 };
 846                 (txt_resp, txt_rrsig)
 847         }
 848
 849         fn matcorallo_dnskey() -> (Vec<DnsKey>, Vec<RR>) {
 850                 let com_dnskeys = com_dnskey().0;
 851                 let mut matcorallo_ds = vec![DS {
 852                         name: "matcorallo.com.".try_into().unwrap(), key_tag: 24930, alg: 13, digest_type: 2,
 853                         digest: Vec::from_hex("693E990CBB1CE1095E387092D3C04BCE907C008891F32A88D41D3ECB129E5E23").unwrap(),
 854                 }];
 855                 let ds_rrsig = RRSig {
 856                         name: "matcorallo.com.".try_into().unwrap(), ty: DS::TYPE, alg: 13, labels: 2, orig_ttl: 86400,
 857                         expiration: 1707628636, inception: 1707019636, key_tag: 4534, key_name: "com.".try_into().unwrap(),
 858                         signature: base64::decode("l9b+DhtnJSIzR6y4Bwx+0L9kep77UNCBoTg74RTSL6oMrQd8w4OobHxzwDyXqnLfyxVP18V+AnQp4DdJ2nUW1g==").unwrap(),
 859                 };
 860                 verify_rrsig(&ds_rrsig, &com_dnskeys, matcorallo_ds.iter().collect()).unwrap();
 861                 let dnskeys = vec![DnsKey {
 862                         name: "matcorallo.com.".try_into().unwrap(), flags: 257, protocol: 3, alg: 13,
 863                         pubkey: base64::decode("pfO3ow3SrKhLS7AMEi3b5W9P28nCOB9vryxfSXhqMcXFP1x9V4xAt0/JLr0zNodsqRD/8d9Yhu4Wf3hnSlaavw==").unwrap(),
 864                 }, DnsKey {
 865                         name: "matcorallo.com.".try_into().unwrap(), flags: 256, protocol: 3, alg: 13,
 866                         pubkey: base64::decode("OO6LQTV1mnRsFgn6YQoyeo/SDqS3eajfVv8WGQVnuSYO/bTS9St1tJiox2fgU6wRWDU3chhjz1Pj0unKUAQKig==").unwrap(),
 867                 }];
 868                 let dnskey_rrsig = RRSig {
 869                         name: "matcorallo.com.".try_into().unwrap(), ty: DnsKey::TYPE, alg: 13, labels: 2, orig_ttl: 604800,
 870                         expiration: 1708309135, inception: 1707094135, key_tag: 24930, key_name: "matcorallo.com.".try_into().unwrap(),
 871                         signature: base64::decode("2MKg3bTn9zf4ThwCoKRFadqD6l1D6SuLksRieKxFC0QQnzUOCRgZSK2/IlT0DMEoM0+mGrJZo7UG79UILMGUyg==").unwrap(),
 872                 };
 873                 verify_dnskey_rrsig(&dnskey_rrsig, &matcorallo_ds, dnskeys.iter().collect()).unwrap();
 874                 let rrs = vec![matcorallo_ds.pop().unwrap().into(), ds_rrsig.into(),
 875                         dnskeys[0].clone().into(), dnskeys[1].clone().into(), dnskey_rrsig.into()];
 876                 (dnskeys, rrs)
 877         }
 878
 879         fn matcorallo_txt_record() -> (Txt, RRSig) {
 880                 let txt_resp = Txt {
 881                         name: "txt_test.matcorallo.com.".try_into().unwrap(),
 882                         data: "dnssec_prover_test".to_owned().into_bytes(),
 883                 };
 884                 let txt_rrsig = RRSig {
 885                         name: "txt_test.matcorallo.com.".try_into().unwrap(),
 886                         ty: Txt::TYPE, alg: 13, labels: 3, orig_ttl: 30, expiration: 1708319203,
 887                         inception: 1707104203, key_tag: 34530, key_name: "matcorallo.com.".try_into().unwrap(),
 888                         signature: base64::decode("4vaE5Jex2VvIT39JpuMNT7Ds7O0OfzTik5f8WcRRxO0IJnGAO16syAsNUkNkNqsMYknnjHDF0lI4agszgzdpsw==").unwrap(),
 889                 };
 890                 (txt_resp, txt_rrsig)
 891         }
 892
 893         #[test]
 894         fn check_txt_record_a() {
 895                 let dnskeys = mattcorallo_dnskey().0;
 896                 let (txt, txt_rrsig) = mattcorallo_txt_record();
 897                 let txt_resp = [txt];
 898                 verify_rrsig(&txt_rrsig, &dnskeys, txt_resp.iter().collect()).unwrap();
 899         }
 900
 901         #[test]
 902         fn check_single_txt_proof() {
 903                 let mut rr_stream = Vec::new();
 904                 for rr in root_dnskey().1 { write_rr(&rr, 1, &mut rr_stream); }
 905                 for rr in com_dnskey().1 { write_rr(&rr, 1, &mut rr_stream); }
 906                 for rr in mattcorallo_dnskey().1 { write_rr(&rr, 1, &mut rr_stream); }
 907                 let (txt, txt_rrsig) = mattcorallo_txt_record();
 908                 for rr in [RR::Txt(txt), RR::RRSig(txt_rrsig)] { write_rr(&rr, 1, &mut rr_stream); }
 909
 910                 let mut rrs = parse_rr_stream(&rr_stream).unwrap();
 911                 rrs.shuffle(&mut rand::rngs::OsRng);
 912                 let verified_rrs = verify_rr_stream(&rrs).unwrap();
 913                 assert_eq!(verified_rrs.len(), 1);
 914                 if let RR::Txt(txt) = &verified_rrs[0] {
 915                         assert_eq!(txt.name.0, "matt.user._bitcoin-payment.mattcorallo.com.");
 916                         assert_eq!(txt.data, b"bitcoin:?b12=lno1qsgqmqvgm96frzdg8m0gc6nzeqffvzsqzrxqy32afmr3jn9ggkwg3egfwch2hy0l6jut6vfd8vpsc3h89l6u3dm4q2d6nuamav3w27xvdmv3lpgklhg7l5teypqz9l53hj7zvuaenh34xqsz2sa967yzqkylfu9xtcd5ymcmfp32h083e805y7jfd236w9afhavqqvl8uyma7x77yun4ehe9pnhu2gekjguexmxpqjcr2j822xr7q34p078gzslf9wpwz5y57alxu99s0z2ql0kfqvwhzycqq45ehh58xnfpuek80hw6spvwrvttjrrq9pphh0dpydh06qqspp5uq4gpyt6n9mwexde44qv7lstzzq60nr40ff38u27un6y53aypmx0p4qruk2tf9mjwqlhxak4znvna5y");
 917                 } else { panic!(); }
 918         }
 919
 920         #[test]
 921         fn check_txt_record_b() {
 922                 let dnskeys = matcorallo_dnskey().0;
 923                 let (txt, txt_rrsig) = matcorallo_txt_record();
 924                 let txt_resp = [txt];
 925                 verify_rrsig(&txt_rrsig, &dnskeys, txt_resp.iter().collect()).unwrap();
 926         }
 927
 928         #[test]
 929         fn check_double_txt_proof() {
 930                 let mut rr_stream = Vec::new();
 931                 for rr in root_dnskey().1 { write_rr(&rr, 1, &mut rr_stream); }
 932                 for rr in com_dnskey().1 { write_rr(&rr, 1, &mut rr_stream); }
 933                 for rr in mattcorallo_dnskey().1 { write_rr(&rr, 1, &mut rr_stream); }
 934                 let (txt, txt_rrsig) = mattcorallo_txt_record();
 935                 for rr in [RR::Txt(txt), RR::RRSig(txt_rrsig)] { write_rr(&rr, 1, &mut rr_stream); }
 936                 for rr in matcorallo_dnskey().1 { write_rr(&rr, 1, &mut rr_stream); }
 937                 let (txt, txt_rrsig) = matcorallo_txt_record();
 938                 for rr in [RR::Txt(txt), RR::RRSig(txt_rrsig)] { write_rr(&rr, 1, &mut rr_stream); }
 939
 940                 let mut rrs = parse_rr_stream(&rr_stream).unwrap();
 941                 rrs.shuffle(&mut rand::rngs::OsRng);
 942                 let mut verified_rrs = verify_rr_stream(&rrs).unwrap();
 943                 verified_rrs.sort();
 944                 assert_eq!(verified_rrs.len(), 2);
 945                 if let RR::Txt(txt) = &verified_rrs[0] {
 946                         assert_eq!(txt.name.0, "matt.user._bitcoin-payment.mattcorallo.com.");
 947                         assert_eq!(txt.data, b"bitcoin:?b12=lno1qsgqmqvgm96frzdg8m0gc6nzeqffvzsqzrxqy32afmr3jn9ggkwg3egfwch2hy0l6jut6vfd8vpsc3h89l6u3dm4q2d6nuamav3w27xvdmv3lpgklhg7l5teypqz9l53hj7zvuaenh34xqsz2sa967yzqkylfu9xtcd5ymcmfp32h083e805y7jfd236w9afhavqqvl8uyma7x77yun4ehe9pnhu2gekjguexmxpqjcr2j822xr7q34p078gzslf9wpwz5y57alxu99s0z2ql0kfqvwhzycqq45ehh58xnfpuek80hw6spvwrvttjrrq9pphh0dpydh06qqspp5uq4gpyt6n9mwexde44qv7lstzzq60nr40ff38u27un6y53aypmx0p4qruk2tf9mjwqlhxak4znvna5y");
 948                 } else { panic!(); }
 949                 if let RR::Txt(txt) = &verified_rrs[1] {
 950                         assert_eq!(txt.name.0, "txt_test.matcorallo.com.");
 951                         assert_eq!(txt.data, b"dnssec_prover_test");
 952                 } else { panic!(); }
 953         }
 954
 955         #[test]
 956         fn rfc9102_parse_test() {
 957                 // Note that this is the `AuthenticationChain` field only, and ignores the
 958                 // `ExtSupportLifetime` field (stripping the top two 0 bytes from the front).
 959 let rfc9102_test_vector = Vec::from_hex("045f343433045f74637003777777076578616d706c6503636f6d000034000100000e1000230301018bd1da95272f7fa4ffb24137fc0ed03aae67e5c4d8b3c50734e1050a7920b922045f343433045f74637003777777076578616d706c6503636f6d00002e000100000e10005f00340d0500000e105fc6d9005bfdda80074e076578616d706c6503636f6d00ce1d3adeb7dc7cee656d61cfb472c5977c8c9caeae9b765155c518fb107b6a1fe0355fbaaf753c192832fa621fa73a8b85ed79d374117387598fcc812e1ef3fb076578616d706c6503636f6d000030000100000e1000440101030d2670355e0c894d9cfea6c5af6eb7d458b57a50ba88272512d8241d8541fd54adf96ec956789a51ceb971094b3bb3f4ec49f64c686595be5b2e89e8799c7717cc076578616d706c6503636f6d00002e000100000e10005f00300d0200000e105fc6d9005bfdda80074e076578616d706c6503636f6d004628383075b8e34b743a209b27ae148d110d4e1a246138a91083249cb4a12a2d9bc4c2d7ab5eb3afb9f5d1037e4d5da8339c162a9298e9be180741a8ca74accc076578616d706c6503636f6d00002b00010002a3000024074e0d02e9b533a049798e900b5c29c90cd25a986e8a44f319ac3cd302bafc08f5b81e16076578616d706c6503636f6d00002e00010002a3000057002b0d020002a3005fc6d9005bfdda80861703636f6d00a203e704a6facbeb13fc9384fdd6de6b50de5659271f38ce81498684e6363172d47e2319fdb4a22a58a231edc2f1ff4fb2811a1807be72cb5241aa26fdaee03903636f6d00003000010002a30000440100030dec8204e43a25f2348c52a1d3bce3a265aa5d11b43dc2a471162ff341c49db9f50a2e1a41caf2e9cd20104ea0968f7511219f0bdc56b68012cc3995336751900b03636f6d00003000010002a30000440101030d45b91c3bef7a5d99a7a7c8d822e33896bc80a777a04234a605a4a8880ec7efa4e6d112c73cd3d4c65564fa74347c873723cc5f643370f166b43dedff836400ff03636f6d00003000010002a30000440101030db3373b6e22e8e49e0e1e591a9f5bd9ac5e1a0f86187fe34703f180a9d36c958f71c4af48ce0ebc5c792a724e11b43895937ee53404268129476eb1aed323939003636f6d00002e00010002a300005700300d010002a3005fc6d9005bfdda8049f303636f6d0018a948eb23d44f80abc99238fcb43c5a18debe57004f7343593f6deb6ed71e04654a433f7aa1972130d9bd921c73dcf63fcf665f2f05a0aaebafb059dc12c96503636f6d00002e00010002a300005700300d010002a3005fc6d9005bfdda80708903636f6d006170e6959bd9ed6e575837b6f580bd99dbd24a44682b0a359626a246b1812f5f9096b75e157e77848f068ae0085e1a609fc19298c33b736863fbccd4d81f5eb203636f6d00002b000100015180002449f30d0220f7a9db42d0e2042fbbb9f9ea015941202f9eabb94487e658c188e7bcb5211503636f6d00002b000100015180002470890d02ad66b3276f796223aa45eda773e92c6d98e70643bbde681db342a9e5cf2bb38003636f6d00002e0001000151800053002b0d01000151805fc6d9005bfdda807cae00122e276d45d9e9816f7922ad6ea2e73e82d26fce0a4b718625f314531ac92f8ae82418df9b898f989d32e80bc4deaba7c4a7c8f172adb57ced7fb5e77a784b0700003000010001518000440100030dccacfe0c25a4340fefba17a254f706aac1f8d14f38299025acc448ca8ce3f561f37fc3ec169fe847c8fcbe68e358ff7c71bb5ee1df0dbe518bc736d4ce8dfe1400003000010001518000440100030df303196789731ddc8a6787eff24cacfeddd032582f11a75bb1bcaa5ab321c1d7525c2658191aec01b3e98ab7915b16d571dd55b4eae51417110cc4cdd11d171100003000010001518000440101030dcaf5fe54d4d48f16621afb6bd3ad2155bacf57d1faad5bac42d17d948c421736d9389c4c4011666ea95cf17725bd0fa00ce5e714e4ec82cfdfacc9b1c863ad4600002e000100015180005300300d00000151805fc6d9005bfdda80b79d00de7a6740eeecba4bda1e5c2dd4899b2c965893f3786ce747f41e50d9de8c0a72df82560dfb48d714de3283ae99a49c0fcb50d3aaadb1a3fc62ee3a8a0988b6be").unwrap();
 960
 961                 let mut rrs = parse_rr_stream(&rfc9102_test_vector).unwrap();
 962                 rrs.shuffle(&mut rand::rngs::OsRng);
 963                 let verified_rrs = verify_rr_stream(&rrs).unwrap();
 964                 assert_eq!(verified_rrs.len(), 1);
 965                 if let RR::TLSA(tlsa) = &verified_rrs[0] {
 966                         assert_eq!(tlsa.cert_usage, 3);
 967                         assert_eq!(tlsa.selector, 1);
 968                         assert_eq!(tlsa.data_ty, 1);
 969                         assert_eq!(tlsa.data, Vec::from_hex("8bd1da95272f7fa4ffb24137fc0ed03aae67e5c4d8b3c50734e1050a7920b922").unwrap());
 970                 } else { panic!(); }
 971         }
 972 }