Switch to libfido2 bindings

Cargo.lock

@@ -2,17 +2,6 @@
 # It is not intended for manual editing.
 version = 3
 
-[[package]]
-name = "aes"
-version = "0.8.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac1f845298e95f983ff1944b728ae08b8cebab80d684f0a832ed0fc74dfa27e2"
-dependencies = [
- "cfg-if",
- "cipher",
- "cpufeatures",
-]
-
 [[package]]
 name = "anyhow"
 version = "1.0.72"
@@ -70,12 +59,6 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4c7f02d4ea65f2c1853089ffd8d2787bdbc63de2f0d29dedbcf8ccdfa0ccd4cf"
 
-[[package]]
-name = "base64"
-version = "0.21.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "604178f6c5c21f02dc555784810edfb88d34ac2c73b2eae109655649ee73ce3d"
-
 [[package]]
 name = "base64ct"
 version = "1.6.0"
@@ -91,15 +74,6 @@ dependencies = [
  "generic-array",
 ]
 
-[[package]]
-name = "block-padding"
-version = "0.3.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a8894febbff9f758034a5b8e12d87918f56dfc64a8e1fe757d65e29041538d93"
-dependencies = [
- "generic-array",
-]
-
 [[package]]
 name = "bumpalo"
 version = "3.13.0"
@@ -112,15 +86,6 @@ version = "1.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
 
-[[package]]
-name = "cbc"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "26b52a9543ae338f279b96b0b9fed9c8093744685043739079ce85cd58f289a6"
-dependencies = [
- "cipher",
-]
-
 [[package]]
 name = "cc"
 version = "1.0.82"
@@ -136,33 +101,6 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
-[[package]]
-name = "ciborium"
-version = "0.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "effd91f6c78e5a4ace8a5d3c0b6bfaec9e2baaef55f3efc00e45fb2e477ee926"
-dependencies = [
- "ciborium-io",
- "ciborium-ll",
- "serde",
-]
-
-[[package]]
-name = "ciborium-io"
-version = "0.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cdf919175532b369853f5d5e20b26b43112613fd6fe7aee757e35f7a44642656"
-
-[[package]]
-name = "ciborium-ll"
-version = "0.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "defaa24ecc093c77630e6c15e17c51f5e187bf35ee514f4e2d67baaa96dae22b"
-dependencies = [
- "ciborium-io",
- "half",
-]
-
 [[package]]
 name = "cipher"
 version = "0.4.4"
@@ -210,29 +148,6 @@ dependencies = [
  "typenum",
 ]
 
-[[package]]
-name = "ctap-hid-fido2"
-version = "3.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3726fa3f7f978ce0a222ea73c13490115f95e7a31db3061d7c4c91bea58ea01a"
-dependencies = [
- "aes",
- "anyhow",
- "base64",
- "byteorder",
- "cbc",
- "hex",
- "hidapi",
- "num",
- "pad",
- "ring",
- "serde",
- "serde_cbor",
- "strum",
- "strum_macros",
- "x509-parser",
-]
-
 [[package]]
 name = "data-encoding"
 version = "2.4.0"
@@ -325,6 +240,12 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "equivalent"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+
 [[package]]
 name = "ff"
 version = "0.13.0"
@@ -369,34 +290,10 @@ dependencies = [
 ]
 
 [[package]]
-name = "half"
+name = "hashbrown"
-version = "1.8.2"
+version = "0.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eabb4a44450da02c90444cf74558da904edde8fb4e9035a9a6a4e15445af0bd7"
+checksum = "2c6201b9ff9fd90a5a3bac2e56a830d0caa509576f0e503818ee82c181b3437a"
-
-[[package]]
-name = "heck"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
-
-[[package]]
-name = "hex"
-version = "0.4.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
-
-[[package]]
-name = "hidapi"
-version = "1.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "798154e4b6570af74899d71155fb0072d5b17e6aa12f39c8ef22c60fb8ec99e7"
-dependencies = [
- "cc",
- "libc",
- "pkg-config",
- "winapi",
-]
 
 [[package]]
 name = "hmac"
@@ -407,13 +304,22 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "indexmap"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d5477fe2230a79769d8dc68e0eabf5437907c0457a5614a9e8dddb67f65eb65d"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
 [[package]]
 name = "inout"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a0c10553d664a4d0bcff9f4215d0aac67a639cc68ef660840afe309b807bc9f5"
 dependencies = [
- "block-padding",
  "generic-array",
 ]
 
@@ -447,6 +353,26 @@ version = "0.2.147"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b4668fb0ea861c1df094127ac5f1da3409a82116a4ba74fca2e58ef927159bb3"
 
+[[package]]
+name = "libfido2"
+version = "0.1.0"
+dependencies = [
+ "libfido2-sys",
+ "num_enum",
+ "paste",
+ "thiserror",
+]
+
+[[package]]
+name = "libfido2-sys"
+version = "0.2.0"
+dependencies = [
+ "anyhow",
+ "cfg-if",
+ "pkg-config",
+ "vcpkg",
+]
+
 [[package]]
 name = "libm"
 version = "0.2.7"
@@ -481,20 +407,6 @@ dependencies = [
  "minimal-lexical",
 ]
 
-[[package]]
-name = "num"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b05180d69e3da0e530ba2a1dae5110317e49e3b7f3d41be227dc5f92e49ee7af"
-dependencies = [
- "num-bigint",
- "num-complex",
- "num-integer",
- "num-iter",
- "num-rational",
- "num-traits",
-]
-
 [[package]]
 name = "num-bigint"
 version = "0.4.3"
@@ -524,12 +436,14 @@ dependencies = [
 ]
 
 [[package]]
-name = "num-complex"
+name = "num-derive"
-version = "0.4.3"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "02e0d21255c828d6f128a1e41534206671e8c3ea0c62f32291e808dc82cff17d"
+checksum = "9e6a0fd4f737c707bd9086cc16c925f294943eb62eb71499e9fd4cf71f8b9f4e"
 dependencies = [
- "num-traits",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.28",
 ]
 
 [[package]]
@@ -553,18 +467,6 @@ dependencies = [
  "num-traits",
 ]
 
-[[package]]
-name = "num-rational"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0638a1c9d0a3c0914158145bc76cff373a75a627e6ecbfb71cbe6f453a5a19b0"
-dependencies = [
- "autocfg",
- "num-bigint",
- "num-integer",
- "num-traits",
-]
-
 [[package]]
 name = "num-traits"
 version = "0.2.16"
@@ -575,6 +477,27 @@ dependencies = [
  "libm",
 ]
 
+[[package]]
+name = "num_enum"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70bf6736f74634d299d00086f02986875b3c2d924781a6a2cb6c201e73da0ceb"
+dependencies = [
+ "num_enum_derive",
+]
+
+[[package]]
+name = "num_enum_derive"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56ea360eafe1022f7cc56cd7b869ed57330fb2453d0c7831d99b74c65d2f5597"
+dependencies = [
+ "proc-macro-crate",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.28",
+]
+
 [[package]]
 name = "oid-registry"
 version = "0.6.1"
@@ -615,13 +538,10 @@ dependencies = [
 ]
 
 [[package]]
-name = "pad"
+name = "paste"
-version = "0.1.6"
+version = "1.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d2ad9b889f1b12e0b9ee24db044b5129150d5eada288edc800f789928dc8c0e3"
+checksum = "de3145af08024dea9fa9914f381a17b8fc6034dfb00f3a84013f7ff43f29ed4c"
-dependencies = [
- "unicode-width",
-]
 
 [[package]]
 name = "pem-rfc7468"
@@ -674,6 +594,16 @@ dependencies = [
  "elliptic-curve",
 ]
 
+[[package]]
+name = "proc-macro-crate"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f4c021e1093a56626774e81216a4ce732a735e5bad4868a03f3ed65ca0c3919"
+dependencies = [
+ "once_cell",
+ "toml_edit",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.66"
@@ -778,12 +708,6 @@ dependencies = [
  "nom",
 ]
 
-[[package]]
-name = "rustversion"
-version = "1.0.14"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7ffc183a10b4478d04cbbbfc96d0873219d962dd5accaff2ffbd4ceb7df837f4"
-
 [[package]]
 name = "sec1"
 version = "0.7.3"
@@ -803,30 +727,6 @@ name = "serde"
 version = "1.0.183"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32ac8da02677876d532745a130fc9d8e6edfa81a269b107c5b00829b91d8eb3c"
-dependencies = [
- "serde_derive",
-]
-
-[[package]]
-name = "serde_cbor"
-version = "0.11.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2bef2ebfde456fb76bbcf9f59315333decc4fda0b2b44b420243c11e0f5ec1f5"
-dependencies = [
- "half",
- "serde",
-]
-
-[[package]]
-name = "serde_derive"
-version = "1.0.183"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aafe972d60b0b9bee71a91b92fee2d4fb3c9d7e8f6b179aa99f27203d99a4816"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.28",
-]
 
 [[package]]
 name = "sha2"
@@ -916,33 +816,14 @@ name = "ssh_attest_verifier"
 version = "0.1.0"
 dependencies = [
  "anyhow",
- "ciborium",
+ "libfido2",
- "ctap-hid-fido2",
+ "num-derive",
  "ssh-encoding",
  "ssh-key",
  "thiserror",
  "x509-parser",
 ]
 
-[[package]]
-name = "strum"
-version = "0.24.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "063e6045c0e62079840579a7e47a355ae92f60eb74daaf156fb1e84ba164e63f"
-
-[[package]]
-name = "strum_macros"
-version = "0.24.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1e385be0d24f186b4ce2f9982191e7101bb737312ad61c1f2f984f34bcf85d59"
-dependencies = [
- "heck",
- "proc-macro2",
- "quote",
- "rustversion",
- "syn 1.0.109",
-]
-
 [[package]]
 name = "subtle"
 version = "2.5.0"
@@ -985,18 +866,18 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "1.0.44"
+version = "1.0.47"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "611040a08a0439f8248d1990b111c95baa9c704c805fa1f62104b39655fd7f90"
+checksum = "97a802ec30afc17eee47b2855fc72e0c4cd62be9b4efe6591edde0ec5bd68d8f"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.44"
+version = "1.0.47"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "090198534930841fab3a5d1bb637cde49e339654e606195f8d9c76eeb081dc96"
+checksum = "6bb623b56e39ab7dcd4b1b98bb6c8f8d907ed255b18de254088016b27a8ee19b"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1031,6 +912,23 @@ dependencies = [
  "time-core",
 ]
 
+[[package]]
+name = "toml_datetime"
+version = "0.6.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7cda73e2f1397b1262d6dfdcef8aafae14d1de7748d66822d3bfeeb6d03e5e4b"
+
+[[package]]
+name = "toml_edit"
+version = "0.19.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f8123f27e969974a3dfba720fdb560be359f57b44302d280ba72e76a74480e8a"
+dependencies = [
+ "indexmap",
+ "toml_datetime",
+ "winnow",
+]
+
 [[package]]
 name = "typenum"
 version = "1.16.0"
@@ -1043,12 +941,6 @@ version = "1.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "301abaae475aa91687eb82514b328ab47a211a533026cb25fc3e519b86adfc3c"
 
-[[package]]
-name = "unicode-width"
-version = "0.1.10"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c0edd1e5b14653f783770bce4a4dabb4a5108a5370a5f5d8cfe8710c361f6c8b"
-
 [[package]]
 name = "unicode-xid"
 version = "0.2.4"
@@ -1061,6 +953,12 @@ version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a156c684c91ea7d62626509bce3cb4e1d9ed5c4d978f7b4352658f96a4c26b4a"
 
+[[package]]
+name = "vcpkg"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "accd4ea62f7bb7a82fe23066fb0957d48ef677f6eeb8215f372f52e48bb32426"
+
 [[package]]
 name = "version_check"
 version = "0.9.4"
@@ -1159,6 +1057,15 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
+[[package]]
+name = "winnow"
+version = "0.5.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7c2e3184b9c4e92ad5167ca73039d0c42476302ab603e2fec4487511f38ccefc"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "x509-parser"
 version = "0.15.1"

Cargo.toml

@@ -7,8 +7,8 @@ edition = "2021"
 
 [dependencies]
 anyhow = "1.0.72"
-ciborium = "0.2.1"
+libfido2 = { version = "0.1.0", path = "../libfido2" }
-ctap-hid-fido2 = "3.5.0"
+num-derive = "0.4.0"
 ssh-encoding = "0.2.0"
 ssh-key = { version = "0.6.0" }
 thiserror = "1.0.44"

src/error.rs

@@ -1,4 +1,3 @@
-use ssh_key::Algorithm;
 use thiserror::Error;
 use x509_parser::prelude::X509Error;
 
@@ -20,8 +19,6 @@ pub enum Error {
     InvalidRootCa(String),
     #[error("FIDO public key type unsupported")]
     UnsupportedFidoKeyType,
-    #[error("SSH public key type {} does not match FIDO public key type {}", .ssh.as_str(), .fido.as_str())]
-    SshFidoTypeMismatch { ssh: Algorithm, fido: Algorithm },
     #[error("SSH public key des not match FIDO public key")]
     SshFidoKeyMismatch,
 }

src/lib.rs

@@ -1,14 +1,11 @@
 mod error;
 mod ssh_attest;
 
-use ctap_hid_fido2::{
-    public_key::PublicKeyType,
-    verifier,
-};
 pub use error::Error;
+use libfido2::{cred::{Credential, CredType}, fido_init};
 use ssh_attest::SshAttestationInfo;
 use ssh_encoding::Decode;
-use ssh_key::{public::KeyData, Algorithm, PublicKey};
+use ssh_key::{public::KeyData, PublicKey, Algorithm};
 pub use x509_parser;
 use x509_parser::{prelude::*, x509::X509Name};
 
@@ -25,13 +22,26 @@ pub fn verify_attestation(
     challenge: Vec<u8>,
     ssh_pubkey: PublicKey,
 ) -> Result<(), Error> {
+    fido_init(true);
     // Decode the SSH attestation file
     let attestation = SshAttestationInfo::decode(&mut ssh_attest.as_slice())
         .map_err(|e| Error::AttestationDecodeError(e))?;
     let attestation_cert = attestation
         .decode_cert()
         .map_err(|e| Error::AttestationCertDecodeError(e))?;
-    let attestation = attestation.to_fido_attestation().map_err(|_e| Error::AttestationInvalidAuthData)?;
+
+    // Reconstruct the credential from the attestation
+    let mut credential = Credential::new().unwrap();
+    match ssh_pubkey.algorithm() {
+        Algorithm::SkEcdsaSha2NistP256 => credential.set_type(CredType::Ecdsa256).unwrap(),
+        Algorithm::SkEd25519 => credential.set_type(CredType::Ed25519).unwrap(),
+        _ => return Err(Error::NonFidoSshKey.into()),
+    };
+    credential.set_authdata_raw(attestation.auth_data.as_ref().unwrap().as_slice()).unwrap();
+    credential.set_sig(attestation.enroll_sig.as_slice()).unwrap();
+    credential.set_clientdata(challenge.as_slice()).unwrap();
+    credential.set_x509(attestation.attestation_cert.as_slice()).unwrap();
+    credential.set_fmt("packed").unwrap();
 
     // Extract the RPID from the SSH public key
     let application = match ssh_pubkey.key_data() {
@@ -40,9 +50,10 @@ pub fn verify_attestation(
         _ => return Err(Error::NonFidoSshKey.into()),
     };
 
+    credential.set_rp(application, "").unwrap();
+
     // Verify the attestation RPID & signature
-    let verify_result = verifier::verify_attestation(&application, &challenge, &attestation);
+    if  credential.verify().is_err() {
-    if !verify_result.is_success {
         return Err(Error::AttestationVerificationFailed);
     }
 
@@ -61,21 +72,6 @@ pub fn verify_attestation(
         return Err(Error::InvalidAttestationCertSignature.into());
     }
 
-    let fido_pubkey = &verify_result.credential_public_key;
-
-    // Verify the FIDO public key is the same type as the SSH public key
-    let fido_pubkey_alg = match fido_pubkey.key_type {
-        PublicKeyType::Ecdsa256 => Algorithm::SkEcdsaSha2NistP256,
-        PublicKeyType::Ed25519 => Algorithm::SkEd25519,
-        PublicKeyType::Unknown => return Err(Error::UnsupportedFidoKeyType),
-    };
-
-    if fido_pubkey_alg != ssh_pubkey.algorithm() {
-        return Err(Error::SshFidoTypeMismatch {
-            ssh: ssh_pubkey.algorithm(),
-            fido: fido_pubkey_alg,
-        });
-    }
 
     // Verify that the  SSH public key data matches the FIDO public key data
     let key_data = match ssh_pubkey.key_data() {
@@ -83,7 +79,7 @@ pub fn verify_attestation(
         KeyData::SkEd25519(key) => key.public_key().0.as_slice(),
         _ => unreachable!(),
     };
-    if key_data != fido_pubkey.der {
+    if key_data != credential.pubkey() {
         return Err(Error::SshFidoKeyMismatch.into());
     }
     Ok(())

src/main.rs

@@ -27,9 +27,9 @@ fn main() -> anyhow::Result<()> {
         })
         .collect::<Result<Vec<_>, _>>()?;
 
-    let ssh_attest = std::fs::read("id_ecdsa_rustgen_sk_attest.bin")?;
+    let ssh_attest = std::fs::read("id_ed25519-sk_attest.bin")?;
-    let challenge = std::fs::read("id_ecdsa_rustgen_sk_attest_chall.bin")?;
+    let challenge = std::fs::read("id_ed25519-sk_attest_chall.bin")?;
-    let ssh_pubkey = ssh_key::PublicKey::read_openssh_file(Path::new("id_ecdsa_rustgen_sk.pub"))?;
+    let ssh_pubkey = ssh_key::PublicKey::read_openssh_file(Path::new("id_ed25519-sk.pub"))?;
 
     verify_attestation(root_cas, ssh_attest, challenge, ssh_pubkey)?;
     println!("Attestation verified successfully");

src/ssh_attest.rs

@@ -1,7 +1,5 @@
 use std::str::FromStr;
 
-use ciborium::Value;
-use ctap_hid_fido2::fidokey::make_credential::{Attestation, make_credential_response};
 use ssh_encoding::{Decode, Label, LabelError};
 use x509_parser::{nom::Finish, prelude::*};
 
@@ -49,43 +47,6 @@ impl SshAttestationInfo {
             .finish()
             .map(|(_, cert)| cert)
     }
-
-    pub fn to_fido_attestation(&self) -> Result<Attestation, anyhow::Error> {
-       let mut attestation_map_bytes = Vec::new();
-        ciborium::into_writer(
-            &Value::from(
-                [
-                    (0x01.into(), "packed".into()),
-                    (
-                        0x02.into(),
-                        self.auth_data.as_deref().unwrap().into(),
-                    ),
-                    (
-                        0x03.into(),
-                        [
-                            // TODO: Don't hardcode algorithm
-                            // -7: ECDSA P256
-                            ("alg".into(), (-7).into()),
-                            ("sig".into(), self.enroll_sig.as_slice().into()),
-                            (
-                                "x5c".into(),
-                                [Value::from(self.attestation_cert.as_slice())]
-                                    .as_slice()
-                                    .into(),
-                            ),
-                        ]
-                        .as_slice()
-                        .into(),
-                    ),
-                ]
-                .as_slice(),
-            ),
-            &mut attestation_map_bytes,
-        )
-        .expect("Failed to serialize CBOR attestation info");
-        make_credential_response::parse_cbor(&attestation_map_bytes)
-
-    }
 }
 
 impl Decode for SshAttestationInfo {