Validate key type with algo in encode/decode

src/algorithms.rs

@@ -2,6 +2,13 @@ use crate::errors::{Error, ErrorKind, Result};
 use serde::{Deserialize, Serialize};
 use std::str::FromStr;
 
+#[derive(Debug, Eq, PartialEq, Copy, Clone, Serialize, Deserialize)]
+pub(crate) enum AlgorithmFamily {
+    Hmac,
+    Rsa,
+    Ec,
+}
+
 /// The algorithms supported for signing/verifying JWTs
 #[derive(Debug, PartialEq, Copy, Clone, Serialize, Deserialize)]
 pub enum Algorithm {
@@ -58,6 +65,21 @@ impl FromStr for Algorithm {
     }
 }
 
+impl Algorithm {
+    pub(crate) fn family(self) -> AlgorithmFamily {
+        match self {
+            Algorithm::HS256 | Algorithm::HS384 | Algorithm::HS512 => AlgorithmFamily::Hmac,
+            Algorithm::RS256
+            | Algorithm::RS384
+            | Algorithm::RS512
+            | Algorithm::PS256
+            | Algorithm::PS384
+            | Algorithm::PS512 => AlgorithmFamily::Rsa,
+            Algorithm::ES256 | Algorithm::ES384 => AlgorithmFamily::Ec,
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

src/decoding.rs

@@ -2,6 +2,7 @@ use std::borrow::Cow;
 
 use serde::de::DeserializeOwned;
 
+use crate::algorithms::AlgorithmFamily;
 use crate::crypto::verify;
 use crate::errors::{new_error, ErrorKind, Result};
 use crate::header::Header;
@@ -40,37 +41,70 @@ pub(crate) enum DecodingKeyKind<'a> {
 /// This key can be re-used so make sure you only initialize it once if you can for better performance
 #[derive(Debug, Clone, PartialEq)]
 pub struct DecodingKey<'a> {
+    pub(crate) family: AlgorithmFamily,
     pub(crate) kind: DecodingKeyKind<'a>,
 }
 
 impl<'a> DecodingKey<'a> {
     /// If you're using HMAC, use this.
     pub fn from_secret(secret: &'a [u8]) -> Self {
-        DecodingKey { kind: DecodingKeyKind::SecretOrDer(Cow::Borrowed(secret)) }
+        DecodingKey {
+            family: AlgorithmFamily::Hmac,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Borrowed(secret)),
+        }
+    }
+
+    /// If you're using HMAC with a base64 encoded, use this.
+    pub fn from_base64_secret(secret: &str) -> Result<Self> {
+        let out = base64::decode(&secret)?;
+        Ok(DecodingKey {
+            family: AlgorithmFamily::Hmac,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(out)),
+        })
     }
 
     /// If you are loading a public RSA key in a PEM format, use this.
     pub fn from_rsa_pem(key: &'a [u8]) -> Result<Self> {
         let pem_key = PemEncodedKey::new(key)?;
         let content = pem_key.as_rsa_key()?;
-        Ok(DecodingKey { kind: DecodingKeyKind::SecretOrDer(Cow::Owned(content.to_vec())) })
+        Ok(DecodingKey {
+            family: AlgorithmFamily::Rsa,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(content.to_vec())),
+        })
     }
 
     /// If you have (n, e) RSA public key components, use this.
     pub fn from_rsa_components(modulus: &'a str, exponent: &'a str) -> Self {
-        DecodingKey { kind: DecodingKeyKind::RsaModulusExponent { n: modulus, e: exponent } }
+        DecodingKey {
+            family: AlgorithmFamily::Rsa,
+            kind: DecodingKeyKind::RsaModulusExponent { n: modulus, e: exponent },
+        }
     }
 
     /// If you have a ECDSA public key in PEM format, use this.
     pub fn from_ec_pem(key: &'a [u8]) -> Result<Self> {
         let pem_key = PemEncodedKey::new(key)?;
         let content = pem_key.as_ec_public_key()?;
-        Ok(DecodingKey { kind: DecodingKeyKind::SecretOrDer(Cow::Owned(content.to_vec())) })
+        Ok(DecodingKey {
+            family: AlgorithmFamily::Ec,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Owned(content.to_vec())),
+        })
     }
 
-    /// If you know what you're doing and have the DER encoded public key, use this.
-    pub fn from_der(der: &'a [u8]) -> Self {
-        DecodingKey { kind: DecodingKeyKind::SecretOrDer(Cow::Borrowed(der)) }
+    /// If you know what you're doing and have a RSA DER encoded public key, use this.
+    pub fn from_rsa_der(der: &'a [u8]) -> Self {
+        DecodingKey {
+            family: AlgorithmFamily::Rsa,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Borrowed(der)),
+        }
+    }
+
+    /// If you know what you're doing and have a RSA EC encoded public key, use this.
+    pub fn from_ec_der(der: &'a [u8]) -> Self {
+        DecodingKey {
+            family: AlgorithmFamily::Ec,
+            kind: DecodingKeyKind::SecretOrDer(Cow::Borrowed(der)),
+        }
     }
 
     pub(crate) fn as_bytes(&self) -> &[u8] {
@@ -104,6 +138,12 @@ pub fn decode<T: DeserializeOwned>(
     key: &DecodingKey,
     validation: &Validation,
 ) -> Result<TokenData<T>> {
+    for alg in &validation.algorithms {
+        if key.family != alg.family() {
+            return Err(new_error(ErrorKind::InvalidAlgorithm));
+        }
+    }
+
     let (signature, message) = expect_two!(token.rsplitn(2, '.'));
     let (claims, header) = expect_two!(message.rsplitn(2, '.'));
     let header = Header::from_encoded(header)?;

src/encoding.rs

@@ -1,7 +1,8 @@
 use serde::ser::Serialize;
 
+use crate::algorithms::AlgorithmFamily;
 use crate::crypto;
-use crate::errors::Result;
+use crate::errors::{new_error, ErrorKind, Result};
 use crate::header::Header;
 use crate::pem::decoder::PemEncodedKey;
 use crate::serialization::b64_encode_part;
@@ -10,13 +11,20 @@ use crate::serialization::b64_encode_part;
 /// This key can be re-used so make sure you only initialize it once if you can for better performance
 #[derive(Debug, Clone, PartialEq)]
 pub struct EncodingKey {
+    pub(crate) family: AlgorithmFamily,
     content: Vec<u8>,
 }
 
 impl EncodingKey {
-    /// If you're using HMAC, use that.
+    /// If you're using a HMAC secret that is not base64, use that.
     pub fn from_secret(secret: &[u8]) -> Self {
-        EncodingKey { content: secret.to_vec() }
+        EncodingKey { family: AlgorithmFamily::Hmac, content: secret.to_vec() }
+    }
+
+    /// If you have a base64 HMAC secret, use that.
+    pub fn from_base64_secret(secret: &str) -> Result<Self> {
+        let out = base64::decode(&secret)?;
+        Ok(EncodingKey { family: AlgorithmFamily::Hmac, content: out })
     }
 
     /// If you are loading a RSA key from a .pem file.
@@ -24,7 +32,7 @@ impl EncodingKey {
     pub fn from_rsa_pem(key: &[u8]) -> Result<Self> {
         let pem_key = PemEncodedKey::new(key)?;
         let content = pem_key.as_rsa_key()?;
-        Ok(EncodingKey { content: content.to_vec() })
+        Ok(EncodingKey { family: AlgorithmFamily::Rsa, content: content.to_vec() })
     }
 
     /// If you are loading a ECDSA key from a .pem file
@@ -32,12 +40,17 @@ impl EncodingKey {
     pub fn from_ec_pem(key: &[u8]) -> Result<Self> {
         let pem_key = PemEncodedKey::new(key)?;
         let content = pem_key.as_ec_private_key()?;
-        Ok(EncodingKey { content: content.to_vec() })
+        Ok(EncodingKey { family: AlgorithmFamily::Ec, content: content.to_vec() })
     }
 
-    /// If you know what you're doing and have the DER-encoded key, for RSA or ECDSA
-    pub fn from_der(der: &[u8]) -> Self {
-        EncodingKey { content: der.to_vec() }
+    /// If you know what you're doing and have the DER-encoded key, for RSA only
+    pub fn from_rsa_der(der: &[u8]) -> Self {
+        EncodingKey { family: AlgorithmFamily::Rsa, content: der.to_vec() }
+    }
+
+    /// If you know what you're doing and have the DER-encoded key, for ECDSA
+    pub fn from_ec_der(der: &[u8]) -> Self {
+        EncodingKey { family: AlgorithmFamily::Ec, content: der.to_vec() }
     }
 
     pub(crate) fn inner(&self) -> &[u8] {
@@ -68,6 +81,9 @@ impl EncodingKey {
 /// let token = encode(&Header::default(), &my_claims, &EncodingKey::from_secret("secret".as_ref())).unwrap();
 /// ```
 pub fn encode<T: Serialize>(header: &Header, claims: &T, key: &EncodingKey) -> Result<String> {
+    if key.family != header.alg.family() {
+        return Err(new_error(ErrorKind::InvalidAlgorithm));
+    }
     let encoded_header = b64_encode_part(&header)?;
     let encoded_claims = b64_encode_part(&claims)?;
     let message = [encoded_header.as_ref(), encoded_claims.as_ref()].join(".");

src/errors.rs

@@ -56,7 +56,8 @@ pub enum ErrorKind {
     InvalidSubject,
     /// When a token’s nbf claim represents a time in the future
     ImmatureSignature,
-    /// When the algorithm in the header doesn't match the one passed to `decode`
+    /// When the algorithm in the header doesn't match the one passed to `decode` or the encoding/decoding key
+    /// used doesn't match the alg requested
     InvalidAlgorithm,
 
     // 3rd party errors

tests/ecdsa/mod.rs

@@ -17,8 +17,11 @@ fn round_trip_sign_verification_pk8() {
     let privkey = include_bytes!("private_ecdsa_key.pk8");
     let pubkey = include_bytes!("public_ecdsa_key.pk8");
 
-    let encrypted = sign("hello world", &EncodingKey::from_der(privkey), Algorithm::ES256).unwrap();
-    let is_valid = verify(&encrypted, "hello world", &DecodingKey::from_der(pubkey), Algorithm::ES256).unwrap();
+    let encrypted =
+        sign("hello world", &EncodingKey::from_ec_der(privkey), Algorithm::ES256).unwrap();
+    let is_valid =
+        verify(&encrypted, "hello world", &DecodingKey::from_ec_der(pubkey), Algorithm::ES256)
+            .unwrap();
     assert!(is_valid);
 }
 

tests/hmac.rs

@@ -102,6 +102,18 @@ fn decode_token_wrong_algorithm() {
     claims.unwrap();
 }
 
+#[test]
+#[should_panic(expected = "InvalidAlgorithm")]
+fn encode_wrong_alg_family() {
+    let my_claims = Claims {
+        sub: "b@b.com".to_string(),
+        company: "ACME".to_string(),
+        exp: Utc::now().timestamp() + 10000,
+    };
+    let claims = encode(&Header::default(), &my_claims, &EncodingKey::from_rsa_der(b"secret"));
+    claims.unwrap();
+}
+
 #[test]
 fn decode_token_with_bytes_secret() {
     let token = "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJiQGIuY29tIiwiY29tcGFueSI6IkFDTUUiLCJleHAiOjI1MzI1MjQ4OTF9.Hm0yvKH25TavFPz7J_coST9lZFYH1hQo0tvhvImmaks";

tests/rsa/mod.rs

@@ -57,11 +57,9 @@ fn round_trip_sign_verification_der() {
     let pubkey_der = include_bytes!("public_rsa_key.der");
 
     for &alg in RSA_ALGORITHMS {
-        let encrypted =
-            sign("hello world", &EncodingKey::from_der(privkey_der), alg).unwrap();
+        let encrypted = sign("hello world", &EncodingKey::from_rsa_der(privkey_der), alg).unwrap();
         let is_valid =
-            verify(&encrypted, "hello world", &DecodingKey::from_der(pubkey_der), alg)
-                .unwrap();
+            verify(&encrypted, "hello world", &DecodingKey::from_rsa_der(pubkey_der), alg).unwrap();
         assert!(is_valid);
     }
 }