feat(identity): make rand optional

identity/Cargo.toml

@@ -14,7 +14,7 @@ categories = ["cryptography"]
 [dependencies]
 asn1_der = { version = "0.7.6", optional = true }
 bs58 = { version = "0.5.0", optional = true }
-ed25519-dalek = { version = "2.0", optional = true, features = ["rand_core"] }
+ed25519-dalek = { version = "2.0", optional = true }
 hkdf = { version = "0.12.3", optional = true }
 libsecp256k1 = { version = "0.7.0", optional = true }
 log = "0.4"
@@ -33,11 +33,14 @@ zeroize = { version = "1.6", optional = true }
 ring = { version = "0.16.9", features = ["alloc", "std"], default-features = false, optional = true}
 
 [features]
-secp256k1 = [ "dep:libsecp256k1", "dep:asn1_der", "dep:rand", "dep:sha2", "dep:hkdf", "dep:zeroize" ]
-ecdsa = [ "dep:p256", "dep:rand", "dep:void", "dep:zeroize", "dep:sec1", "dep:sha2", "dep:hkdf" ]
+secp256k1 = [ "dep:libsecp256k1", "dep:asn1_der", "dep:sha2", "dep:hkdf", "dep:zeroize" ]
+ecdsa = [ "dep:p256", "dep:void", "dep:zeroize", "dep:sec1", "dep:sha2", "dep:hkdf" ]
 rsa = [ "dep:ring", "dep:asn1_der", "dep:rand", "dep:zeroize" ]
 ed25519 = [ "dep:ed25519-dalek", "dep:rand", "dep:zeroize", "dep:sha2", "dep:hkdf" ]
-peerid = [ "dep:multihash", "dep:bs58", "dep:rand", "dep:thiserror", "dep:sha2", "dep:hkdf" ]
+peerid = [ "dep:multihash", "dep:bs58", "dep:thiserror", "dep:sha2", "dep:hkdf" ]
+rand = ["dep:rand", "ed25519-dalek?/rand_core"]
+
+default = ["rand"]
 
 [dev-dependencies]
 quickcheck = { workspace = true }

identity/src/ecdsa.rs

@@ -44,6 +44,7 @@ pub struct Keypair {
 
 impl Keypair {
     /// Generate a new random ECDSA keypair.
+    #[cfg(feature = "rand")]
     pub fn generate() -> Keypair {
         Keypair::from(SecretKey::generate())
     }
@@ -265,6 +266,7 @@ mod tests {
     use super::*;
 
     #[test]
+    #[cfg(feature = "rand")]
     fn sign_verify() {
         let pair = Keypair::generate();
         let pk = pair.public();

identity/src/ed25519.rs

@@ -34,6 +34,7 @@ pub struct Keypair(ed25519::SigningKey);
 
 impl Keypair {
     /// Generate a new random Ed25519 keypair.
+    #[cfg(feature = "rand")]
     pub fn generate() -> Keypair {
         Keypair::from(SecretKey::generate())
     }
@@ -181,6 +182,7 @@ impl fmt::Debug for SecretKey {
 
 impl SecretKey {
     /// Generate a new Ed25519 secret key.
+    #[cfg(feature = "rand")]
     pub fn generate() -> SecretKey {
         let signing = ed25519::SigningKey::generate(&mut rand::rngs::OsRng);
         SecretKey(signing.to_bytes())
@@ -213,6 +215,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(feature = "rand")]
     fn ed25519_keypair_encode_decode() {
         fn prop() -> bool {
             let kp1 = Keypair::generate();
@@ -224,6 +227,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(feature = "rand")]
     fn ed25519_keypair_from_secret() {
         fn prop() -> bool {
             let kp1 = Keypair::generate();
@@ -235,6 +239,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(feature = "rand")]
     fn ed25519_signature() {
         let kp = Keypair::generate();
         let pk = kp.public();

identity/src/keypair.rs

@@ -102,23 +102,23 @@
 
 impl Keypair {
     /// Generate a new Ed25519 keypair.
-    #[cfg(feature = "ed25519")]
+    #[cfg(all(feature = "ed25519", feature = "rand"))]
     pub fn generate_ed25519() -> Keypair {
         Keypair {
             keypair: KeyPairInner::Ed25519(ed25519::Keypair::generate()),
         }
     }
 
     /// Generate a new Secp256k1 keypair.
-    #[cfg(feature = "secp256k1")]
+    #[cfg(all(feature = "secp256k1", feature = "rand"))]
     pub fn generate_secp256k1() -> Keypair {
         Keypair {
             keypair: KeyPairInner::Secp256k1(secp256k1::Keypair::generate()),
         }
     }
 
     /// Generate a new ECDSA keypair.
-    #[cfg(feature = "ecdsa")]
+    #[cfg(all(feature = "ecdsa", feature = "rand"))]
     pub fn generate_ecdsa() -> Keypair {
         Keypair {
             keypair: KeyPairInner::Ecdsa(ecdsa::Keypair::generate()),
@@ -343,21 +343,36 @@
         }
     }
 
-    /// Deterministically derive a new secret from this [`Keypair`], taking into account the provided domain.
-    ///
-    /// This works for all key types except RSA where it returns `None`.
-    ///
-    /// # Example
-    ///
-    /// ```
-    /// # fn main() {
-    /// # use libp2p_identity as identity;
-    ///
-    /// let key = identity::Keypair::generate_ed25519();
-    ///
-    /// let new_key = key.derive_secret(b"my encryption key").expect("can derive secret for ed25519");
-    /// # }
-    /// ```
+    #[doc = r##"
+    Deterministically derive a new secret from this [`Keypair`], taking into account the provided domain.
+
+    This works for all key types except RSA where it returns `None`.
+
+    # Example
+
+    "##]
+    #[cfg_attr(
+        feature = "rand",
+        doc = r##"
+    ```
+    "##
+    )]
+    #[cfg_attr(
+        not(feature = "rand"),
+        doc = r##"
+    ```ignore
+    "##
+    )]
+    #[doc = r##"
+    # fn main() {
+    # use libp2p_identity as identity;
+    let key = identity::Keypair::generate_ed25519();
+
+    let new_key = key.derive_secret(b"my encryption key").expect("can derive secret for ed25519");
+    # }
+    ```
+    "##
+    ]
     #[allow(unused_variables, unreachable_code)]
     pub fn derive_secret(&self, domain: &[u8]) -> Option<[u8; 32]> {
         #[cfg(any(
@@ -382,7 +397,7 @@
             #[cfg(feature = "ed25519")]
             KeyPairInner::Ed25519(ref inner) => Some(inner.secret().to_bytes()),
             #[cfg(all(feature = "rsa", not(target_arch = "wasm32")))]
             KeyPairInner::Rsa(_) => return None,
             #[cfg(feature = "secp256k1")]
             KeyPairInner::Secp256k1(ref inner) => Some(inner.secret().to_bytes()),
             #[cfg(feature = "ecdsa")]
@@ -916,7 +931,7 @@
     }
 
     #[test]
-    #[cfg(feature = "ed25519")]
+    #[cfg(all(feature = "ed25519", feature = "rand"))]
     fn test_publickey_from_ed25519_public_key() {
         let pubkey = Keypair::generate_ed25519().public();
         let ed25519_pubkey = pubkey
@@ -931,7 +946,7 @@
     }
 
     #[test]
-    #[cfg(feature = "secp256k1")]
+    #[cfg(all(feature = "secp256k1", feature = "rand"))]
     fn test_publickey_from_secp256k1_public_key() {
         let pubkey = Keypair::generate_secp256k1().public();
         let secp256k1_pubkey = pubkey
@@ -945,7 +960,7 @@
     }
 
     #[test]
-    #[cfg(feature = "ecdsa")]
+    #[cfg(all(feature = "ecdsa", feature = "rand"))]
     fn test_publickey_from_ecdsa_public_key() {
         let pubkey = Keypair::generate_ecdsa().public();
         let ecdsa_pubkey = pubkey.clone().try_into_ecdsa().expect("A ecdsa keypair");

identity/src/peer_id.rs

@@ -18,6 +18,7 @@
 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
 
+#[cfg(feature = "rand")]
 use rand::Rng;
 use sha2::Digest as _;
 use std::{convert::TryFrom, fmt, str::FromStr};
@@ -101,6 +102,7 @@ impl PeerId {
     /// Generates a random peer ID from a cryptographically secure PRNG.
     ///
     /// This is useful for randomly walking on a DHT, or for testing purposes.
+    #[cfg(feature = "rand")]
     pub fn random() -> PeerId {
         let peer_id = rand::thread_rng().gen::<[u8; 32]>();
         PeerId {
@@ -247,22 +249,23 @@ mod tests {
     use super::*;
 
     #[test]
-    #[cfg(feature = "ed25519")]
+    #[cfg(all(feature = "ed25519", feature = "rand"))]
     fn peer_id_into_bytes_then_from_bytes() {
         let peer_id = crate::Keypair::generate_ed25519().public().to_peer_id();
         let second = PeerId::from_bytes(&peer_id.to_bytes()).unwrap();
         assert_eq!(peer_id, second);
     }
 
     #[test]
-    #[cfg(feature = "ed25519")]
+    #[cfg(all(feature = "ed25519", feature = "rand"))]
     fn peer_id_to_base58_then_back() {
         let peer_id = crate::Keypair::generate_ed25519().public().to_peer_id();
         let second: PeerId = peer_id.to_base58().parse().unwrap();
         assert_eq!(peer_id, second);
     }
 
     #[test]
+    #[cfg(feature = "rand")]
     fn random_peer_id_is_valid() {
         for _ in 0..5000 {
             let peer_id = PeerId::random();

identity/src/secp256k1.rs

@@ -38,6 +38,7 @@ pub struct Keypair {
 
 impl Keypair {
     /// Generate a new sec256k1 `Keypair`.
+    #[cfg(feature = "rand")]
     pub fn generate() -> Keypair {
         Keypair::from(SecretKey::generate())
     }
@@ -88,6 +89,7 @@ impl fmt::Debug for SecretKey {
 
 impl SecretKey {
     /// Generate a new random Secp256k1 secret key.
+    #[cfg(feature = "rand")]
     pub fn generate() -> SecretKey {
         SecretKey(libsecp256k1::SecretKey::random(&mut rand::thread_rng()))
     }
@@ -226,6 +228,7 @@ mod tests {
     use super::*;
 
     #[test]
+    #[cfg(feature = "rand")]
     fn secp256k1_secret_from_bytes() {
         let sk1 = SecretKey::generate();
         let mut sk_bytes = [0; 32];