1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684
//! Cryptographic operation wrapper for Webauthn. This module exists to //! allow ease of auditing, safe operation wrappers for the webauthn library, //! and cryptographic provider abstraction. This module currently uses OpenSSL //! as the cryptographic primitive provider. #![allow(non_camel_case_types)] use openssl::{bn, ec, hash, nid, pkey, rsa, sha, sign, x509}; use std::convert::TryFrom; // use super::constants::*; use super::error::*; use crate::proto::Aaguid; // use super::proto::*; // Why OpenSSL over another rust crate? // - Well, the openssl crate allows us to reconstruct a public key from the // x/y group coords, where most others want a pkcs formatted structure. As // a result, it's easiest to use openssl as it gives us exactly what we need // for these operations, and despite it's many challenges as a library, it // has resources and investment into it's maintenance, so we can a least // assert a higher level of confidence in it that <backyard crypto here>. // Object({Integer(-3): Bytes([48, 185, 178, 204, 113, 186, 105, 138, 190, 33, 160, 46, 131, 253, 100, 177, 91, 243, 126, 128, 245, 119, 209, 59, 186, 41, 215, 196, 24, 222, 46, 102]), Integer(-2): Bytes([158, 212, 171, 234, 165, 197, 86, 55, 141, 122, 253, 6, 92, 242, 242, 114, 158, 221, 238, 163, 127, 214, 120, 157, 145, 226, 232, 250, 144, 150, 218, 138]), Integer(-1): U64(1), Integer(1): U64(2), Integer(3): I64(-7)}) // fn verify_signature( pkey: &pkey::PKeyRef<pkey::Public>, stype: COSEContentType, signature: &[u8], verification_data: &[u8], ) -> Result<bool, WebauthnError> { let mut verifier = match stype { COSEContentType::ECDSA_SHA256 => sign::Verifier::new(hash::MessageDigest::sha256(), &pkey) .map_err(|e| WebauthnError::OpenSSLError(e)), COSEContentType::RS256 => { let mut verifier = sign::Verifier::new(hash::MessageDigest::sha256(), &pkey) .map_err(|e| WebauthnError::OpenSSLError(e))?; verifier .set_rsa_padding(rsa::Padding::PKCS1) .map_err(|e| WebauthnError::OpenSSLError(e))?; Ok(verifier) } COSEContentType::INSECURE_RS1 => { let mut verifier = sign::Verifier::new(hash::MessageDigest::sha1(), &pkey) .map_err(|e| WebauthnError::OpenSSLError(e))?; verifier .set_rsa_padding(rsa::Padding::PKCS1) .map_err(|e| WebauthnError::OpenSSLError(e))?; Ok(verifier) } _ => Err(WebauthnError::COSEKeyInvalidType), }?; verifier .update(verification_data) .map_err(|e| WebauthnError::OpenSSLError(e))?; verifier .verify(signature) .map_err(|e| WebauthnError::OpenSSLError(e)) } /// An X509PublicKey. This is what is otherwise known as a public certificate /// which comprises a public key and other signed metadata related to the issuer /// of the key. pub struct X509PublicKey { pubk: x509::X509, t: COSEContentType, } impl std::fmt::Debug for X509PublicKey { fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result { write!(f, "X509PublicKey") } } impl TryFrom<(&[u8], COSEContentType)> for X509PublicKey { type Error = WebauthnError; // Must be DER bytes. If you have PEM, base64decode first! fn try_from((d, t): (&[u8], COSEContentType)) -> Result<Self, Self::Error> { let pubk = x509::X509::from_der(d).map_err(|e| WebauthnError::OpenSSLError(e))?; match &t { COSEContentType::ECDSA_SHA256 => { let pk = pubk .public_key() .map_err(|e| WebauthnError::OpenSSLError(e))?; let ec_key = pk.ec_key().map_err(|e| WebauthnError::OpenSSLError(e))?; ec_key .check_key() .map_err(|e| WebauthnError::OpenSSLError(e))?; let ec_grpref = ec_key.group(); let ec_curve = ec_grpref .curve_name() .ok_or(WebauthnError::OpenSSLErrorNoCurveName)?; if ec_curve != nid::Nid::X9_62_PRIME256V1 { return Err(WebauthnError::CertificatePublicKeyInvalid); } } _ => {} } Ok(X509PublicKey { pubk, t }) } } impl X509PublicKey { pub(crate) fn verify_signature( &self, signature: &Vec<u8>, verification_data: &Vec<u8>, ) -> Result<bool, WebauthnError> { let pkey = self .pubk .public_key() .map_err(|e| WebauthnError::OpenSSLError(e))?; verify_signature( &pkey, self.t, signature.as_slice(), verification_data.as_slice(), ) } pub(crate) fn assert_tpm_attest_req(&self) -> Result<(), WebauthnError> { // TPM attestation certificate MUST have the following fields/extensions: // Version MUST be set to 3. // version is not an attribute in openssl rust so I can't verify this // Subject field MUST be set to empty. let subject_name_ref = self.pubk.subject_name(); if subject_name_ref.entries().count() != 0 { return Err(WebauthnError::AttestationCertificateRequirementsNotMet); } // The Subject Alternative Name extension MUST be set as defined in [TPMv2-EK-Profile] section 3.2.9. // https://www.trustedcomputinggroup.org/wp-content/uploads/Credential_Profile_EK_V2.0_R14_published.pdf // // I actually have no idea how to parse or process this ... // self.pubk.subject_alt_names // Today there is no way to view eku/bc from openssl rust // The Extended Key Usage extension MUST contain the "joint-iso-itu-t(2) internationalorganizations(23) 133 tcg-kp(8) tcg-kp-AIKCertificate(3)" OID. // The Basic Constraints extension MUST have the CA component set to false. // An Authority Information Access (AIA) extension with entry id-ad-ocsp and a CRL Distribution // Point extension [RFC5280] are both OPTIONAL as the status of many attestation certificates is // available through metadata services. See, for example, the FIDO Metadata Service [FIDOMetadataService]. Ok(()) } pub(crate) fn assert_packed_attest_req(&self) -> Result<(), WebauthnError> { // Verify that attestnCert meets the requirements in § 8.2.1 Packed Attestation // Statement Certificate Requirements. // https://w3c.github.io/webauthn/#sctn-packed-attestation-cert-requirements // The attestation certificate MUST have the following fields/extensions: // Version MUST be set to 3 (which is indicated by an ASN.1 INTEGER with value 2). // Subject field MUST be set to: // // Subject-C // ISO 3166 code specifying the country where the Authenticator vendor is incorporated (PrintableString) // Subject-O // Legal name of the Authenticator vendor (UTF8String) // Subject-OU // Literal string “Authenticator Attestation” (UTF8String) // Subject-CN // A UTF8String of the vendor’s choosing let subject_name_ref = self.pubk.subject_name(); let subject_c = subject_name_ref .entries_by_nid(nid::Nid::from_raw(14)) .into_iter() .take(1) .next(); let subject_o = subject_name_ref .entries_by_nid(nid::Nid::from_raw(17)) .into_iter() .take(1) .next(); let subject_ou = subject_name_ref .entries_by_nid(nid::Nid::from_raw(18)) .into_iter() .take(1) .next(); let subject_cn = subject_name_ref .entries_by_nid(nid::Nid::from_raw(13)) .into_iter() .take(1) .next(); if subject_c.is_none() || subject_o.is_none() || subject_cn.is_none() { return Err(WebauthnError::AttestationCertificateRequirementsNotMet); } match subject_ou { Some(ou) => match ou.data().as_utf8() { Ok(ou_d) => { if ou_d.to_string() != "Authenticator Attestation" { return Err(WebauthnError::AttestationCertificateRequirementsNotMet); } } Err(_) => return Err(WebauthnError::AttestationCertificateRequirementsNotMet), }, None => return Err(WebauthnError::AttestationCertificateRequirementsNotMet), } // If the related attestation root certificate is used for multiple authenticator models, // the Extension OID 1.3.6.1.4.1.45724.1.1.4 (id-fido-gen-ce-aaguid) MUST be present, // containing the AAGUID as a 16-byte OCTET STRING. The extension MUST NOT be marked as critical. // The Basic Constraints extension MUST have the CA component set to false. // An Authority Information Access (AIA) extension with entry id-ad-ocsp and a CRL // Distribution Point extension [RFC5280] are both OPTIONAL as the status of many // attestation certificates is available through authenticator metadata services. See, for // example, the FIDO Metadata Service [FIDOMetadataService]. Ok(()) } pub(crate) fn get_fido_gen_ce_aaguid(&self) -> Option<Aaguid> { None } } /// An ECDSACurve identifier. You probabably will never need to alter /// or use this value, as it is set inside the Credential for you. #[derive(Clone, Debug, Serialize, Deserialize)] pub enum ECDSACurve { // +---------+-------+----------+------------------------------------+ // | Name | Value | Key Type | Description | // +---------+-------+----------+------------------------------------+ // | P-256 | 1 | EC2 | NIST P-256 also known as secp256r1 | // | P-384 | 2 | EC2 | NIST P-384 also known as secp384r1 | // | P-521 | 3 | EC2 | NIST P-521 also known as secp521r1 | // | X25519 | 4 | OKP | X25519 for use w/ ECDH only | // | X448 | 5 | OKP | X448 for use w/ ECDH only | // | Ed25519 | 6 | OKP | Ed25519 for use w/ EdDSA only | // | Ed448 | 7 | OKP | Ed448 for use w/ EdDSA only | // +---------+-------+----------+------------------------------------+ /// Identifies this curve as SECP256R1 (X9_62_PRIME256V1 in OpenSSL) SECP256R1 = 1, /// Identifies this curve as SECP384R1 SECP384R1 = 2, /// Identifies this curve as SECP521R1 SECP521R1 = 3, // /// Identifies this OKP as ED25519 // ED25519 = 6, } impl TryFrom<i128> for ECDSACurve { type Error = WebauthnError; fn try_from(u: i128) -> Result<Self, Self::Error> { match u { 1 => Ok(ECDSACurve::SECP256R1), 2 => Ok(ECDSACurve::SECP384R1), 3 => Ok(ECDSACurve::SECP521R1), _ => Err(WebauthnError::COSEKeyECDSAInvalidCurve), } } } impl ECDSACurve { fn to_openssl_nid(&self) -> nid::Nid { match self { ECDSACurve::SECP256R1 => nid::Nid::X9_62_PRIME256V1, ECDSACurve::SECP384R1 => nid::Nid::SECP384R1, ECDSACurve::SECP521R1 => nid::Nid::SECP521R1, } } } /// A COSE Key Content type, indicating the type of key and hash type /// that should be used with this key. You shouldn't need to alter or /// use this value. #[derive(Copy, Clone, Debug, Serialize, Deserialize, PartialEq)] pub enum COSEContentType { /// Identifies this key as ECDSA (recommended SECP256R1) with SHA256 hashing ECDSA_SHA256 = -7, // recommends curve SECP256R1 /// Identifies this key as ECDSA (recommended SECP384R1) with SHA384 hashing ECDSA_SHA384 = -35, // recommends curve SECP384R1 /// Identifies this key as ECDSA (recommended SECP521R1) with SHA512 hashing ECDSA_SHA512 = -36, // recommends curve SECP521R1 /// Identifies this key as RS256 aka RSASSA-PKCS1-v1_5 w/ SHA-256 RS256 = -257, /// Identifies this key as RS384 aka RSASSA-PKCS1-v1_5 w/ SHA-384 RS384 = -258, /// Identifies this key as RS512 aka RSASSA-PKCS1-v1_5 w/ SHA-512 RS512 = -259, /// Identifies this key as PS256 aka RSASSA-PSS w/ SHA-256 PS256 = -37, /// Identifies this key as PS384 aka RSASSA-PSS w/ SHA-384 PS384 = -38, /// Identifies this key as PS512 aka RSASSA-PSS w/ SHA-512 PS512 = -39, /// Identifies this key as EdDSA (likely curve ed25519) EDDSA = -8, /// Identifies this as an INSECURE RS1 aka RSASSA-PKCS1-v1_5 using SHA-1. This is not /// used by validators, but can exist in some windows hello tpm's INSECURE_RS1 = -65535, } impl TryFrom<i128> for COSEContentType { type Error = WebauthnError; fn try_from(i: i128) -> Result<Self, Self::Error> { match i { -7 => Ok(COSEContentType::ECDSA_SHA256), -35 => Ok(COSEContentType::ECDSA_SHA384), -36 => Ok(COSEContentType::ECDSA_SHA512), -257 => Ok(COSEContentType::RS256), -258 => Ok(COSEContentType::RS384), -259 => Ok(COSEContentType::RS512), -37 => Ok(COSEContentType::PS256), -38 => Ok(COSEContentType::PS384), -39 => Ok(COSEContentType::PS512), -8 => Ok(COSEContentType::EDDSA), -65535 => Ok(COSEContentType::INSECURE_RS1), _ => Err(WebauthnError::COSEKeyECDSAContentType), } } } impl From<&COSEContentType> for i64 { fn from(c: &COSEContentType) -> Self { match c { COSEContentType::ECDSA_SHA256 => -7, COSEContentType::ECDSA_SHA384 => -35, COSEContentType::ECDSA_SHA512 => -6, COSEContentType::RS256 => -257, COSEContentType::RS384 => -258, COSEContentType::RS512 => -259, COSEContentType::PS256 => -37, COSEContentType::PS384 => -38, COSEContentType::PS512 => -39, COSEContentType::EDDSA => -8, COSEContentType::INSECURE_RS1 => -65535, } } } impl COSEContentType { pub(crate) fn only_hash_from_type(&self, input: &[u8]) -> Result<Vec<u8>, WebauthnError> { match self { COSEContentType::INSECURE_RS1 => { // sha1 hash::hash(hash::MessageDigest::sha1(), input) .map(|dbytes| Vec::from(dbytes.as_ref())) .map_err(|e| WebauthnError::OpenSSLError(e)) } _ => Err(WebauthnError::COSEKeyInvalidType), } } } /// A COSE Eliptic Curve Public Key. This is generally the provided credential /// that an authenticator registers, and is used to authenticate the user. /// You will likely never need to interact with this value, as it is part of the Credential /// API. #[derive(Clone, Debug, Serialize, Deserialize)] pub struct COSEEC2Key { /// The curve that this key references. pub curve: ECDSACurve, /// The key's public X coordinate. pub x: [u8; 32], /// The key's public Y coordinate. pub y: [u8; 32], } /// A COSE RSA PublicKey. This is a provided credential from a registered /// authenticator. /// You will likely never need to interact with this value, as it is part of the Credential /// API. #[derive(Clone, Debug, Serialize, Deserialize)] pub struct COSERSAKey { /// An RSA modulus pub n: Vec<u8>, /// An RSA exponent pub e: [u8; 3], } /// The type of Key contained within a COSE value. You should never need /// to alter or change this type. #[derive(Clone, Debug, Serialize, Deserialize)] pub enum COSEKeyType { // +-----------+-------+-----------------------------------------------+ // | Name | Value | Description | // +-----------+-------+-----------------------------------------------+ // | OKP | 1 | Octet Key Pair | // | EC2 | 2 | Elliptic Curve Keys w/ x- and y-coordinate | // | | | pair | // | Symmetric | 4 | Symmetric Keys | // | Reserved | 0 | This value is reserved | // +-----------+-------+-----------------------------------------------+ /// Identifies this as an Eliptic Curve octet key pair EC_OKP, /// Identifies this as an Eliptic Curve EC2 key EC_EC2(COSEEC2Key), // EC_Symmetric, // EC_Reserved, // should always be invalid. /// Identifies this as an RSA key RSA(COSERSAKey), } /// A COSE Key as provided by the Authenticator. You should never need /// to alter or change these values. #[derive(Clone, Debug, Serialize, Deserialize)] pub struct COSEKey { /// The type of key that this contains pub type_: COSEContentType, /// The public key pub key: COSEKeyType, } impl TryFrom<&serde_cbor::Value> for COSEKey { type Error = WebauthnError; fn try_from(d: &serde_cbor::Value) -> Result<COSEKey, Self::Error> { let m = cbor_try_map!(d)?; // See also https://tools.ietf.org/html/rfc8152#section-3.1 // These values look like: // Object({ // // negative (-) values are per-algo specific // Integer(-3): Bytes([48, 185, 178, 204, 113, 186, 105, 138, 190, 33, 160, 46, 131, 253, 100, 177, 91, 243, 126, 128, 245, 119, 209, 59, 186, 41, 215, 196, 24, 222, 46, 102]), // Integer(-2): Bytes([158, 212, 171, 234, 165, 197, 86, 55, 141, 122, 253, 6, 92, 242, 242, 114, 158, 221, 238, 163, 127, 214, 120, 157, 145, 226, 232, 250, 144, 150, 218, 138]), // Integer(-1): U64(1), // Integer(1): U64(2), // algorithm identifier // Integer(3): I64(-7) // content type see https://tools.ietf.org/html/rfc8152#section-8.1 -7 being ES256 + SHA256 // }) // Now each of these integers has a specific meaning, and you need to parse them in order. // First, value 1 for the key type. let key_type_value = m .get(&serde_cbor::Value::Integer(1)) .ok_or(WebauthnError::COSEKeyInvalidCBORValue)?; let key_type = cbor_try_i128!(key_type_value)?; let content_type_value = m .get(&serde_cbor::Value::Integer(3)) .ok_or(WebauthnError::COSEKeyInvalidCBORValue)?; let content_type = cbor_try_i128!(content_type_value)?; // https://www.iana.org/assignments/cose/cose.xhtml // https://www.w3.org/TR/webauthn/#sctn-encoded-credPubKey-examples match key_type { // 1 => {} OctetKey 2 => { // This indicates this is an EC2 key consisting of crv, x, y, which are stored in // crv (-1), x (-2) and y (-3) // Get these values now .... let curve_type_value = m .get(&serde_cbor::Value::Integer(-1)) .ok_or(WebauthnError::COSEKeyInvalidCBORValue)?; let curve_type = cbor_try_i128!(curve_type_value)?; // Let x be the value corresponding to the "-2" key (representing x coordinate) in credentialPublicKey, and confirm its size to be of 32 bytes. If size differs or "-2" key is not found, terminate this algorithm and return an appropriate error. // Let y be the value corresponding to the "-3" key (representing y coordinate) in credentialPublicKey, and confirm its size to be of 32 bytes. If size differs or "-3" key is not found, terminate this algorithm and return an appropriate error. let x_value = m .get(&serde_cbor::Value::Integer(-2)) .ok_or(WebauthnError::COSEKeyInvalidCBORValue)?; let x = cbor_try_bytes!(x_value)?; let y_value = m .get(&serde_cbor::Value::Integer(-3)) .ok_or(WebauthnError::COSEKeyInvalidCBORValue)?; let y = cbor_try_bytes!(y_value)?; if x.len() != 32 || y.len() != 32 { return Err(WebauthnError::COSEKeyECDSAXYInvalid); } // Set the x and y, we know they are proper sizes. let mut x_temp = [0; 32]; x_temp.copy_from_slice(x.as_slice()); let mut y_temp = [0; 32]; y_temp.copy_from_slice(y.as_slice()); // Right, now build the struct. let cose_key = COSEKey { type_: COSEContentType::try_from(content_type)?, key: COSEKeyType::EC_EC2(COSEEC2Key { curve: ECDSACurve::try_from(curve_type)?, x: x_temp, y: y_temp, }), }; // The rfc additionally states: // " Applications MUST check that the curve and the key type are // consistent and reject a key if they are not." // this means feeding the values to openssl to validate them for us! cose_key.validate()?; // return it Ok(cose_key) } 3 => { // RSAKey // -37 -> PS256 // -257 -> RS256 aka RSASSA-PKCS1-v1_5 with SHA-256 // -1 -> n 256 bytes // -2 -> e 3 bytes let n_value = m .get(&serde_cbor::Value::Integer(-1)) .ok_or(WebauthnError::COSEKeyInvalidCBORValue)?; let n = cbor_try_bytes!(n_value)?; let e_value = m .get(&serde_cbor::Value::Integer(-2)) .ok_or(WebauthnError::COSEKeyInvalidCBORValue)?; let e = cbor_try_bytes!(e_value)?; if n.len() != 256 || e.len() != 3 { return Err(WebauthnError::COSEKeyRSANEInvalid); } // Set the n and e, we know they are proper sizes. let mut e_temp = [0; 3]; e_temp.copy_from_slice(e.as_slice()); // Right, now build the struct. let cose_key = COSEKey { type_: COSEContentType::try_from(content_type)?, key: COSEKeyType::RSA(COSERSAKey { n: n.to_vec(), e: e_temp, }), }; cose_key.validate()?; // return it Ok(cose_key) } _ => { log::debug!("try from"); Err(WebauthnError::COSEKeyInvalidType) } } } } impl COSEKey { pub(crate) fn get_alg_key_ecc_x962_raw(&self) -> Result<Vec<u8>, WebauthnError> { // Let publicKeyU2F be the concatenation 0x04 || x || y. // Note: This signifies uncompressed ECC key format. match &self.key { COSEKeyType::EC_EC2(ecpk) => { let r: [u8; 1] = [0x04]; Ok(r.iter() .chain(ecpk.x.iter()) .chain(ecpk.y.iter()) .map(|b| *b) .collect()) } _ => { log::debug!("get_alg_key_ecc_x962_raw"); Err(WebauthnError::COSEKeyInvalidType) } } } pub(crate) fn validate(&self) -> Result<(), WebauthnError> { match &self.key { COSEKeyType::EC_EC2(ec2k) => { // Get the curve type let curve = ec2k.curve.to_openssl_nid(); let ec_group = ec::EcGroup::from_curve_name(curve) .map_err(|e| WebauthnError::OpenSSLError(e))?; let xbn = bn::BigNum::from_slice(&ec2k.x).map_err(|e| WebauthnError::OpenSSLError(e))?; let ybn = bn::BigNum::from_slice(&ec2k.y).map_err(|e| WebauthnError::OpenSSLError(e))?; let ec_key = ec::EcKey::from_public_key_affine_coordinates(&ec_group, &xbn, &ybn) .map_err(|e| WebauthnError::OpenSSLError(e))?; ec_key .check_key() .map_err(|e| WebauthnError::OpenSSLError(e)) } COSEKeyType::RSA(rsak) => { let nbn = bn::BigNum::from_slice(&rsak.n).map_err(|e| WebauthnError::OpenSSLError(e))?; let ebn = bn::BigNum::from_slice(&rsak.e).map_err(|e| WebauthnError::OpenSSLError(e))?; let _rsa_key = rsa::Rsa::from_public_components(nbn, ebn) .map_err(|e| WebauthnError::OpenSSLError(e))?; /* // Only applies to keys with private components! rsa_key .check_key() .map_err(|e| WebauthnError::OpenSSLError(e)) */ Ok(()) } _ => Err(WebauthnError::COSEKeyInvalidType), } } fn get_openssl_pkey(&self) -> Result<pkey::PKey<pkey::Public>, WebauthnError> { match &self.key { COSEKeyType::EC_EC2(ec2k) => { // Get the curve type let curve = ec2k.curve.to_openssl_nid(); let ec_group = ec::EcGroup::from_curve_name(curve) .map_err(|e| WebauthnError::OpenSSLError(e))?; let xbn = bn::BigNum::from_slice(&ec2k.x).map_err(|e| WebauthnError::OpenSSLError(e))?; let ybn = bn::BigNum::from_slice(&ec2k.y).map_err(|e| WebauthnError::OpenSSLError(e))?; let ec_key = ec::EcKey::from_public_key_affine_coordinates(&ec_group, &xbn, &ybn) .map_err(|e| WebauthnError::OpenSSLError(e))?; // Validate the key is sound. IIRC this actually checks the values // are correctly on the curve as specified ec_key .check_key() .map_err(|e| WebauthnError::OpenSSLError(e))?; let p = pkey::PKey::from_ec_key(ec_key).map_err(|e| WebauthnError::OpenSSLError(e))?; Ok(p) } COSEKeyType::RSA(rsak) => { let nbn = bn::BigNum::from_slice(&rsak.n).map_err(|e| WebauthnError::OpenSSLError(e))?; let ebn = bn::BigNum::from_slice(&rsak.e).map_err(|e| WebauthnError::OpenSSLError(e))?; let rsa_key = rsa::Rsa::from_public_components(nbn, ebn) .map_err(|e| WebauthnError::OpenSSLError(e))?; let p = pkey::PKey::from_rsa(rsa_key).map_err(|e| WebauthnError::OpenSSLError(e))?; Ok(p) } _ => { log::debug!("get_openssl_pkey"); Err(WebauthnError::COSEKeyInvalidType) } } } pub(crate) fn verify_signature( &self, signature: &Vec<u8>, verification_data: &Vec<u8>, ) -> Result<bool, WebauthnError> { let pkey = self.get_openssl_pkey()?; verify_signature( &pkey, self.type_, signature.as_slice(), verification_data.as_slice(), ) } } pub(crate) fn compute_sha256(data: &[u8]) -> Vec<u8> { let mut hasher = sha::Sha256::new(); hasher.update(data); hasher.finish().iter().map(|b| *b).collect() }