diff --git a/tor-llcrypto/src/cipher.rs b/tor-llcrypto/src/cipher.rs
index 78de19924..5d7f606b6 100644
--- a/tor-llcrypto/src/cipher.rs
+++ b/tor-llcrypto/src/cipher.rs
@@ -4,6 +4,11 @@
 //! uses AES, and (so far) only uses AES in counter mode.
 
 /// Re-exports implementations of counter-mode AES
+///
+/// These ciphers implement the
+/// [StreamCipher](https://docs.rs/stream-cipher/0.3.2/stream_cipher/trait.StreamCipher.html)
+/// trait, so use the
+/// [stream-cipher](https://docs.rs/stream-cipher/0.3.2/stream_cipher/) crate to access them.
 pub mod aes {
     // These implement StreamCipher.
     pub use aes_ctr::{Aes128Ctr, Aes256Ctr};
diff --git a/tor-llcrypto/src/d.rs b/tor-llcrypto/src/d.rs
index fde11d5aa..e0c278ef6 100644
--- a/tor-llcrypto/src/d.rs
+++ b/tor-llcrypto/src/d.rs
@@ -4,11 +4,9 @@
 //! SHA3, and SHAKE.  We re-export them all here, implementing
 //! the Digest trait.
 //!
-//! Other code should access these digests via the Digest trait and
-//! its friends.
+//! Other code should access these digests via the traits in the
+//! [digest](https://docs.rs/digest/0.8.1/digest/) crate.
 
 pub use sha1::Sha1;
 pub use sha2::{Sha256, Sha512};
 pub use sha3::{Sha3_256, Shake128, Shake256};
-
-
diff --git a/tor-llcrypto/src/lib.rs b/tor-llcrypto/src/lib.rs
index 1cf4bff3f..413dec8ae 100644
--- a/tor-llcrypto/src/lib.rs
+++ b/tor-llcrypto/src/lib.rs
@@ -9,6 +9,7 @@
 //! Encryption is implemented in `cipher`, digests are in `d`, and
 //! public key cryptography (including signatures, encryption, and key
 //! agreement) are in `pk`.
+//!
 
 #![deny(missing_docs)]
 
diff --git a/tor-proto/src/crypto/ll/kdf.rs b/tor-proto/src/crypto/ll/kdf.rs
index 4bf67abc6..8897cef6d 100644
--- a/tor-proto/src/crypto/ll/kdf.rs
+++ b/tor-proto/src/crypto/ll/kdf.rs
@@ -1,5 +1,5 @@
 use crate::{Error, Result, SecretBytes};
-use digest::{ExtendableOutput, Digest};
+use digest::{Digest, ExtendableOutput};
 use tor_llcrypto::d::{Sha1, Sha256, Shake256};
 
 use zeroize::Zeroizing;