added feature assert_devices

Cargo.toml

@@ -21,6 +21,10 @@ untrusted = "0.6"
 rust-crypto = "0.2"
 csv-core = "0.1.6"
 derive_builder = "0.9.0"
+crossbeam = { version = "0.7.3", optional = true }
 [dev-dependencies]
 crossbeam = "0.7.3"
 hex = "0.4.0"
+
+[features]
+assert_devices = ["crossbeam"]

examples/multiple.rs

@@ -1,8 +1,12 @@
 extern crate ctap_hmac as ctap;
 
+use crossbeam::thread;
 use crypto::digest::Digest;
 use crypto::sha2::Sha256;
-use ctap::{FidoCredential, FidoCredentialRequestBuilder, FidoAssertionRequestBuilder, AuthenticatorOptions, FidoDevice, FidoError, FidoResult};
+use ctap::{
+    FidoAssertionRequestBuilder, FidoCredential, FidoCredentialRequestBuilder, FidoDevice,
+    FidoError, FidoResult,
+};
 use failure::_core::time::Duration;
 use hex;
 use std::env::args;
@@ -11,42 +15,41 @@ use std::io::stdin;
 use std::io::stdout;
 use std::sync::mpsc::channel;
 use std::sync::Mutex;
-use crossbeam::thread;
 
 const RP_ID: &str = "ctap_demo";
 
 fn run() -> ctap::FidoResult<()> {
-    let mut credentials = args().skip(1).map(|id| FidoCredential {
-        id: hex::decode(&id).expect("Invalid credential"),
-        public_key: None,
-    }).collect::<Vec<_>>();
+    let mut credentials = args()
+        .skip(1)
+        .map(|id| FidoCredential {
+            id: hex::decode(&id).expect("Invalid credential"),
+            public_key: None,
+        })
+        .collect::<Vec<_>>();
     if credentials.len() == 0 {
-        credentials = ctap::get_devices()?.map(|h| FidoDevice::new(&h).and_then(|mut dev| FidoCredentialRequestBuilder::default()
-            .rp_id(RP_ID).build().unwrap().make_credential(&mut dev))).collect::<FidoResult<Vec<FidoCredential>>>()?;
-    }
-    let credentials = credentials.iter().collect::<Vec<_>>();
-    let (s, r) = channel();
-    thread::scope(|scope| {
-        let handles = ctap::get_devices()?.map(|h| {
-            let req = FidoAssertionRequestBuilder::default().rp_id(RP_ID).credentials(&credentials[..]).build().unwrap();
-            let s = s.clone();
-            scope.spawn(move |_| {
+        credentials = ctap::get_devices()?
+            .map(|h| {
                 FidoDevice::new(&h).and_then(|mut dev| {
-                    req.get_assertion(&mut dev).map(|res| {
-                        s.send(res.clone());
-                        res
-                    })
+                    FidoCredentialRequestBuilder::default()
+                        .rp_id(RP_ID)
+                        .build()
+                        .unwrap()
+                        .make_credential(&mut dev)
                 })
             })
-        }).collect::<Vec<_>>();
-        for h in handles {
-            h.join();
-        }
-        Ok::<(), FidoError>(())
-    }).unwrap();
-    for res in r.iter().take(credentials.len()) {
-        dbg!(res);
+            .collect::<FidoResult<Vec<FidoCredential>>>()?;
     }
+    let credentials = credentials.iter().collect::<Vec<_>>();
+    let req = FidoAssertionRequestBuilder::default()
+        .rp_id(RP_ID)
+        .credentials(&credentials[..])
+        .build()
+        .unwrap();
+    let mut devices = ctap::get_devices()?
+        .map(|handle| FidoDevice::new(&handle))
+        .collect::<FidoResult<Vec<_>>>()?;
+    let (cred, _) = ctap::get_assertion_devices(&req, devices.iter_mut())?;
+    println!("Success, got assertion for: {}", hex::encode(&cred.id));
     Ok(())
 }
 

src/error.rs

@@ -45,9 +45,9 @@ pub enum FidoErrorKind {
     EncryptPin,
     #[fail(display = "Failed to decrypt PIN.")]
     DecryptPin,
-    #[fail(display = "Supplied key has incorrect type.")]
-    VerifySignature,
     #[fail(display = "Failed to verify response signature.")]
+    VerifySignature,
+    #[fail(display = "Supplied key has incorrect type.")]
     KeyType,
     #[fail(display = "Device returned error: {}", _0)]
     CborError(CborErrorCode),

src/lib.rs

@@ -61,6 +61,7 @@ pub mod extensions;
 mod hid_common;
 mod hid_linux;
 mod packet;
+mod util;
 
 use std::cmp;
 use std::fs;
@@ -68,13 +69,11 @@ use std::io::{Cursor, Write};
 use std::u16;
 use std::u8;
 
-use self::cbor::{
-    PublicKeyCredentialDescriptor,
-};
+use self::cbor::{AuthenticatorOptions, PublicKeyCredentialDescriptor};
 pub use self::error::*;
-pub use self::cbor::AuthenticatorOptions;
 use self::hid_linux as hid;
 use self::packet::CtapCommand;
+pub use self::util::*;
 use crate::cbor::{AuthenticatorData, GetAssertionRequest};
 use failure::{Fail, ResultExt};
 use num_traits::FromPrimitive;
@@ -99,7 +98,6 @@ pub struct FidoCredential {
     /// The public key provided by the authenticator, in uncompressed form.
     pub public_key: Option<Vec<u8>>,
 }
-
 /// An opened FIDO authenticator.
 pub struct FidoDevice {
     device: fs::File,
@@ -111,6 +109,46 @@ pub struct FidoDevice {
     aaguid: [u8; 16],
 }
 
+pub struct FidoCancelHandle {
+    device: fs::File,
+    packet_size: u16,
+    channel_id: [u8; 4],
+}
+
+impl FidoCancelHandle {
+    pub fn cancel(&mut self) -> FidoResult<()> {
+        let payload = &[1u8];
+        let to_send = payload.len() as u16;
+        let max_payload = (self.packet_size - 7) as usize;
+        let (frame, payload) = payload.split_at(cmp::min(payload.len(), max_payload));
+        packet::write_init_packet(
+            &mut self.device,
+            64,
+            &self.channel_id,
+            &CtapCommand::Cancel,
+            to_send,
+            frame,
+        )?;
+        if payload.is_empty() {
+            return Ok(());
+        }
+        let max_payload = (self.packet_size - 5) as usize;
+        for (seq, frame) in (0..u8::MAX).zip(payload.chunks(max_payload)) {
+            packet::write_cont_packet(&mut self.device, 64, &self.channel_id, seq, frame)?;
+        }
+        self.device.flush().context(FidoErrorKind::WritePacket)?;
+        Ok(())
+    }
+
+    pub fn cancel_after<T>(&mut self, body: impl Fn(()) -> T) -> FidoResult<T> {
+        let res = body(());
+        match self.cancel() {
+            Ok(_) => Ok(res),
+            Err(e) => Err(e),
+        }
+    }
+}
+
 /// Request a new credential from the authenticator. The `rp_id` should be
 /// a stable string used to identify the party for whom the credential is
 /// created, for convenience it will be returned with the credential.
@@ -198,13 +236,8 @@ pub struct FidoAssertionRequest<'a> {
 }
 
 impl<'a> FidoAssertionRequest<'a> {
-    pub fn get_assertion(
-        &self,
-        device: &mut FidoDevice,
-    ) -> FidoResult<&'a FidoCredential> {
-        device
-            .get_assertion(self)
-            .map(|res| res.0)
+    pub fn get_assertion(&self, device: &mut FidoDevice) -> FidoResult<&'a FidoCredential> {
+        device.get_assertion(self).map(|res| res.0)
     }
 }
 
@@ -324,10 +357,21 @@ impl FidoDevice {
         }
     }
 
+    pub fn cancel_handle(&mut self) -> FidoResult<FidoCancelHandle> {
+        Ok(self
+            .device
+            .try_clone()
+            .map(|device| FidoCancelHandle {
+                device,
+                packet_size: self.packet_size,
+                channel_id: self.channel_id,
+            })
+            .context(FidoErrorKind::Io)?)
+    }
 
     pub fn make_credential(
         &mut self,
-        request: &FidoCredentialRequest<'_>
+        request: &FidoCredentialRequest<'_>,
     ) -> FidoResult<FidoCredential> {
         let rp = cbor::PublicKeyCredentialRpEntity {
             id: request.rp_id,
@@ -343,7 +387,8 @@ impl FidoDevice {
 
         let options = Some(AuthenticatorOptions {
             up: false,
-            uv: request.uv, rk: request.rk
+            uv: request.uv,
+            rk: request.rk,
         });
         if self.needs_pin && self.pin_token.is_none() {
             Err(FidoErrorKind::PinRequired)?
@@ -364,13 +409,17 @@ impl FidoDevice {
             rp,
             user,
             pub_key_cred_params: &pub_key_cred_params,
-            exclude_list: &request.exclude_list.iter()
+            exclude_list: &request
+                .exclude_list
+                .iter()
                 .map(|cred| PublicKeyCredentialDescriptor {
                     cred_type: "public-key".into(),
                     id: cred.id.clone(),
                 })
                 .collect::<Vec<_>>()[..],
-            extensions: &request.extension_data.iter()
+            extensions: &request
+                .extension_data
+                .iter()
                 .map(|(name, data)| (*name, *data))
                 .collect::<Vec<_>>()[..],
             options,
@@ -388,7 +437,7 @@ impl FidoDevice {
                 .attested_credential_data
                 .credential_public_key,
         )?
-            .bytes();
+        .bytes();
         Ok(FidoCredential {
             id: response.auth_data.attested_credential_data.credential_id,
             public_key: Some(Vec::from(&public_key[..])),
@@ -409,7 +458,6 @@ impl FidoDevice {
     /// This method will fail if a PIN is required but the device is not
     /// unlocked or if the device returns malformed data.
 
-
     pub fn get_assertion<'a>(
         &mut self,
         assertion: &FidoAssertionRequest<'a>,
@@ -446,7 +494,7 @@ impl FidoDevice {
             options: Some(AuthenticatorOptions {
                 rk: assertion.rk,
                 uv: assertion.uv,
-                up: assertion.up
+                up: assertion.up,
             }),
             pin_auth: pin_auth,
             pin_protocol: pin_auth.and(Some(0x01)),
@@ -467,19 +515,28 @@ impl FidoDevice {
             })
             .next();
 
-        credential.and_then(|cred| {
-            cred.public_key.as_ref().map(|public_key|
-                Some(crypto::verify_signature(
+        credential
+            .and_then(|cred| {
+                if cred
+                    .public_key
+                    .as_ref()
+                    .map(|public_key| {
+                        crypto::verify_signature(
                             &public_key,
                             &assertion.client_data_hash,
                             &response.auth_data_bytes,
                             &response.signature,
                         )
-            ).unwrap_or(true)).iter().filter_map( |valid| match valid {
-                true => Some(cred),
-                false => None,
-            }).next()
-        }).ok_or(FidoError::from(FidoErrorKind::VerifySignature)).map(|cred| (cred, response.auth_data))
+                    })
+                    .unwrap_or(true)
+                {
+                    Some(cred)
+                } else {
+                    None
+                }
+            })
+            .ok_or(FidoError::from(FidoErrorKind::VerifySignature))
+            .map(|cred| (cred, response.auth_data))
     }
 
     fn cbor(&mut self, request: cbor::Request) -> FidoResult<cbor::Response> {

src/util.rs

@@ -0,0 +1,44 @@
+use crate::cbor::AuthenticatorData;
+use crate::{FidoAssertionRequest, FidoCredential, FidoDevice, FidoErrorKind, FidoResult};
+use std::sync::mpsc::channel;
+#[cfg(feature = "assert_devices")]
+use crossbeam::thread;
+
+/// Will send the `assertion` to all supplied `devices` and return either the first successful assertion or the last error
+#[cfg(feature = "assert_devices")]
+pub fn get_assertion_devices<'a>(
+    assertion: &'a FidoAssertionRequest,
+    devices: impl Iterator<Item = &'a mut FidoDevice>,
+) -> FidoResult<(&'a FidoCredential, AuthenticatorData)> {
+    thread::scope(
+        |scope| -> FidoResult<(&'a FidoCredential, AuthenticatorData)> {
+            let (tx, rx) = channel();
+            let handles = devices
+                .map(|device| {
+                    let cancel = device.cancel_handle()?;
+                    let tx = tx.clone();
+                    let thread_handle =
+                        scope.spawn(move |_| tx.send(device.get_assertion(assertion)));
+                    Ok((cancel, thread_handle))
+                })
+                .collect::<FidoResult<Vec<_>>>()?;
+
+            let mut err = None;
+            for res in rx.iter().take(handles.len()) {
+                match res {
+                    Ok(_) => {
+                        for (mut cancel, join) in handles {
+                            // Canceling out of courtesy don't care if it fails
+                            let _ = cancel.cancel();
+                            let _ = join.join();
+                        }
+                        return res;
+                    }
+                    e => err = Some(e),
+                }
+            }
+            err.unwrap_or(Err(FidoErrorKind::DeviceUnsupported.into()))
+        },
+    )
+    .unwrap()
+}