feat: add passphrase support

Cargo.lock

@@ -90,6 +90,18 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43a49c392881ce6d5c3b8cb70f98717b7c07aabbdff06687b9030dbfbe2725f8"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi",
+ "windows-targets",
+]
+
 [[package]]
 name = "heck"
 version = "0.4.1"
@@ -120,6 +132,7 @@ version = "0.1.0"
 dependencies = [
  "apdu-core",
  "base64",
+ "getrandom",
  "hmac",
  "iso7816-tlv",
  "ouroboros",
@@ -331,6 +344,88 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b928f33d975fc6ad9f86c8f283853ad26bdd5b10b7f1542aa2fa15e2289105a"
 
+[[package]]
+name = "wasi"
+version = "0.13.3+wasi-0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26816d2e1a4a36a2940b96c5296ce403917633dff8f3440e9b236ed6f6bacad2"
+dependencies = [
+ "wit-bindgen-rt",
+]
+
+[[package]]
+name = "windows-targets"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9b724f72796e036ab90c1021d4780d4d3d648aca59e491e6b98e725b84e99973"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_gnullvm",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32a4622180e7a0ec044bb555404c800bc9fd9ec262ec147edd5989ccd0c02cd3"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09ec2a7bb152e2252b53fa7803150007879548bc709c039df7627cabbd05d469"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e9b5ad5ab802e97eb8e295ac6720e509ee4c243f69d781394014ebfe8bbfa0b"
+
+[[package]]
+name = "windows_i686_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0eee52d38c090b3caa76c563b86c3a4bd71ef1a819287c19d586d7334ae8ed66"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "240948bc05c5e7c6dabba28bf89d89ffce3e303022809e73deaefe4f6ec56c66"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "147a5c80aabfbf0c7d901cb5895d1de30ef2907eb21fbbab29ca94c5b08b1a78"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24d5b23dc417412679681396f2b49f3de8c1473deb516bd34410872eff51ed0d"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
+
+[[package]]
+name = "wit-bindgen-rt"
+version = "0.33.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3268f3d866458b787f390cf61f4bbb563b922d091359f9608842999eaee3943c"
+dependencies = [
+ "bitflags",
+]
+
 [[package]]
 name = "yansi"
 version = "1.0.1"

Cargo.toml

@@ -1,6 +1,7 @@
 [dependencies]
 apdu-core = "0.4.0"
 base64 = "0.22.1"
+getrandom = "0.3.1"
 hmac = "0.12.1"
 iso7816-tlv = "0.4.4"
 ouroboros = "0.18.5"

src/example.rs

@@ -30,7 +30,12 @@ fn main() {
     for yubikey in yubikeys {
         let device_label: &str = yubikey;
         println!("Found device with label {}", device_label);
-        let session = OathSession::new(yubikey).unwrap();
+        let mut session = OathSession::new(yubikey).unwrap();
+
+        // session.set_key(&session.derive_key("1234")).unwrap();
+        // session.unlock_session(&session.derive_key("1234")).unwrap();
+        // session.unset_key().unwrap();
+
         println!("YubiKey version is {:?}", session.get_version());
         for c in session.list_oath_codes().unwrap() {
             println!("{}", c);
@@ -49,7 +54,7 @@ fn main() {
             println!("No credentials on device {}", device_label);
         }
 
-        std::thread::sleep(std::time::Duration::from_secs(5)); // show refresh is working
+        std::thread::sleep(std::time::Duration::from_secs(0)); // show refresh is working
 
         // Enumerate the OATH codes
         for oath in codes {

src/lib.rs

@@ -32,10 +32,6 @@ fn _hmac_sha1(key: &[u8], message: &[u8]) -> Vec<u8> {
     mac.finalize().into_bytes().to_vec()
 }
 
-fn _derive_key(salt: &[u8], passphrase: &str) -> Vec<u8> {
-    pbkdf2::pbkdf2_hmac_array::<sha1::Sha1, 16>(passphrase.as_bytes(), salt, 1000).to_vec()
-}
-
 fn _hmac_shorten_key(key: &[u8], algo: HashAlgo) -> Vec<u8> {
     if key.len() > algo.digest_size() {
         algo.get_hash_fun()(key)
@@ -44,14 +40,6 @@ fn _hmac_shorten_key(key: &[u8], algo: HashAlgo) -> Vec<u8> {
     }
 }
 
-pub struct OathSession {
-    version: Vec<u8>,
-    salt: Vec<u8>,
-    challenge: Vec<u8>,
-    transaction_context: TransactionContext,
-    pub name: String,
-}
-
 pub struct RefreshableOathCredential<'a> {
     pub cred: OathCredential,
     pub code: Option<OathCodeDisplay>,
@@ -130,6 +118,15 @@ impl<'a> RefreshableOathCredential<'a> {
     }
 }
 
+pub struct OathSession {
+    version: Vec<u8>,
+    salt: Vec<u8>,
+    challenge: Option<Vec<u8>>,
+    transaction_context: TransactionContext,
+    pub locked: bool,
+    pub name: String,
+}
+
 impl OathSession {
     pub fn new(name: &str) -> Result<Self, Error> {
         let transaction_context = TransactionContext::from_name(name)?;
@@ -142,7 +139,9 @@ impl OathSession {
             println!("{:?}: {:?}", tag, data);
         }
 
+        let challenge = info_map.get(&(Tag::Challenge as u8)).map(Vec::to_owned);
         Ok(Self {
+            locked: challenge.is_some(),
             version: info_map
                 .get(&(Tag::Version as u8))
                 .unwrap_or(&vec![0u8; 0])
@@ -151,10 +150,7 @@ impl OathSession {
                 .get(&(Tag::Name as u8))
                 .unwrap_or(&vec![0u8; 0])
                 .to_owned(),
-            challenge: info_map
+            challenge,
-                .get(&(Tag::Challenge as u8))
-                .unwrap_or(&vec![0u8; 0])
-                .to_owned(),
             name: name.to_string(),
             transaction_context,
         })
@@ -164,6 +160,76 @@ impl OathSession {
         &self.version
     }
 
+    pub fn unlock_session(&mut self, key: &[u8]) -> Result<(), Error> {
+        let chal = match self.challenge.to_owned() {
+            Some(chal) => chal,
+            None => return Ok(()),
+        };
+
+        if !self.locked {
+            return Ok(());
+        }
+
+        let hmac = _hmac_sha1(key, &chal);
+        let random_chal = getrandom::u64().unwrap().to_be_bytes(); // FIXME: unwrap
+        let data = &[
+            to_tlv(Tag::Response, &hmac),
+            to_tlv(Tag::Challenge, &random_chal),
+        ]
+        .concat();
+        let resp =
+            self.transaction_context
+                .apdu(0, Instruction::Validate as u8, 0, 0, Some(data))?;
+        let verification = _hmac_sha1(key, &random_chal);
+        if tlv_to_map(resp.buf)
+            .get(&(Tag::Response as u8))
+            .map(|v| *v == verification)
+            .unwrap_or(false)
+        {
+            self.locked = false;
+            Ok(())
+        } else {
+            Err(Error::FailedAuthentication)
+        }
+    }
+
+    pub fn set_key(&mut self, key: &[u8]) -> Result<(), Error> {
+        let random_chal = getrandom::u64().unwrap().to_be_bytes(); // FIXME: unwrap
+        let hmac = _hmac_sha1(key, &random_chal);
+        let data = &[
+            to_tlv(
+                Tag::Key,
+                &[&[(OathType::Totp as u8) | (HashAlgo::Sha1 as u8); 1], key].concat(),
+            ),
+            to_tlv(Tag::Challenge, &random_chal),
+            to_tlv(Tag::Response, &hmac),
+        ]
+        .concat();
+        self.transaction_context
+            .apdu(0, Instruction::SetCode as u8, 0, 0, Some(data))?;
+        let info_buffer =
+            self.transaction_context
+                .apdu_read_all(0, INS_SELECT, 0x04, 0, Some(&OATH_AID))?;
+        let info_map = tlv_to_map(info_buffer);
+        self.challenge = info_map.get(&(Tag::Challenge as u8)).map(Vec::to_owned);
+        self.locked = self.challenge.is_some();
+
+        self.unlock_session(key)
+    }
+
+    pub fn unset_key(&mut self) -> Result<(), Error> {
+        self.transaction_context.apdu(
+            0,
+            Instruction::SetCode as u8,
+            0,
+            0,
+            Some(&to_tlv(Tag::Key, &[0u8; 0])),
+        )?;
+        self.locked = false;
+        self.challenge = None;
+        Ok(())
+    }
+
     pub fn rename_credential(
         &self,
         old: CredentialIDData,
@@ -190,6 +256,11 @@ impl OathSession {
         )
     }
 
+    pub fn derive_key(&self, passphrase: &str) -> Vec<u8> {
+        pbkdf2::pbkdf2_hmac_array::<sha1::Sha1, 16>(passphrase.as_bytes(), &self.salt, 1000)
+            .to_vec()
+    }
+
     pub fn calculate_code(
         &self,
         cred: OathCredential,

src/transaction.rs

@@ -14,6 +14,7 @@ pub enum Error {
     Pcsc(pcsc::Error),
     Parsing(String),
     DeviceMismatch,
+    FailedAuthentication,
 }
 
 impl Error {
@@ -46,6 +47,7 @@ impl Display for Error {
             Self::Pcsc(error) => f.write_fmt(format_args!("{}", error)),
             Self::Parsing(msg) => f.write_str(msg),
             Self::DeviceMismatch => f.write_str("Devices do not match"),
+            Error::FailedAuthentication => f.write_str("Authentication failure"),
         }
     }
 }