Adapt to mirage_crypto 1.0.0

dream.opam

@@ -54,6 +54,7 @@ depends: [
   "caqti-lwt" {>= "2.0.0"}
   ("conf-libev" {os != "win32"} | "ocaml" {os = "win32"})
   "cstruct" {>= "6.0.0"}
+  "digestif" {>= "0.7"}  # to_raw_string.
   "dream-httpaf" {>= "1.0.0~alpha3"}
   "dream-pure" {>= "1.0.0~alpha2"}
   "dune" {>= "2.7.0"}  # --instrument-with.
@@ -68,8 +69,8 @@ depends: [
   "magic-mime"
   "markup" {>= "1.0.2"}
   "mirage-clock" {>= "3.0.0"}  # now_d_ps : unit -> int * int64.
-  "mirage-crypto" {>= "0.8.1"}  # AES-256-GCM.
-  "mirage-crypto-rng"
+  "mirage-crypto" {>= "1.0.0"}
+  "mirage-crypto-rng" {>= "1.0.0"}
   "mirage-crypto-rng-lwt"
   "multipart_form" {>= "0.4.0"}
   "multipart_form-lwt"

src/cipher/cipher.ml

@@ -70,32 +70,26 @@ struct
 
   let derive_key secret =
     secret
-    |> Cstruct.of_string
-    |> Mirage_crypto.Hash.SHA256.digest
-    |> Mirage_crypto.Cipher_block.AES.GCM.of_secret
+    |> Digestif.SHA256.digest_string
+    |> Digestif.SHA256.to_raw_string
+    |> Mirage_crypto.AES.GCM.of_secret
 
   (* TODO Memoize keys or otherwise avoid key derivation on every call. *)
   let encrypt_with_nonce secret nonce plaintext associated_data =
     let key = derive_key secret in
-    let adata = Option.map Cstruct.of_string associated_data in
+    let adata = associated_data in
     let ciphertext =
-      Mirage_crypto.Cipher_block.AES.GCM.authenticate_encrypt
-        ~key
-        ~nonce
-        ?adata
-        (Cstruct.of_string plaintext)
-      |> Cstruct.to_string
-    in
+      Mirage_crypto.AES.GCM.authenticate_encrypt ~key ~nonce ?adata plaintext in
 
-    "\x00" ^ (Cstruct.to_string nonce) ^ ciphertext
+    "\x00" ^ nonce ^ ciphertext
 
   let encrypt ?associated_data ~secret plaintext =
     encrypt_with_nonce
       secret (Random.random_buffer 12) plaintext associated_data
 
   let test_encrypt ?associated_data ~secret ~nonce plaintext =
     encrypt_with_nonce
-      secret (Cstruct.of_string nonce) plaintext associated_data
+      secret nonce plaintext associated_data
 
   let decrypt ?associated_data ~secret ciphertext =
     let key = derive_key secret in
@@ -105,17 +99,15 @@ struct
       if ciphertext.[0] != prefix then
         None
       else
-        let adata = Option.map Cstruct.of_string associated_data in
+        let adata = associated_data in
         let plaintext =
-          Mirage_crypto.Cipher_block.AES.GCM.authenticate_decrypt
+          Mirage_crypto.AES.GCM.authenticate_decrypt
             ~key
-            ~nonce:(Cstruct.of_string ~off:1 ~len:12 ciphertext)
+            ~nonce:(String.sub ciphertext 1 12)
             ?adata
-            (Cstruct.of_string ciphertext ~off:13)
+            (String.sub ciphertext 13 (String.length ciphertext - 13))
         in
-        match plaintext with
-        | None -> None
-        | Some plaintext -> Some (Cstruct.to_string plaintext)
+        plaintext
 end
 
 let secrets_field =

src/cipher/dune

@@ -3,6 +3,7 @@
  (name dream__cipher)
  (libraries
   cstruct
+  digestif
   dream-pure
   mirage-crypto
   mirage-crypto-rng

src/cipher/random.ml

@@ -22,4 +22,4 @@ let random_buffer n =
   Mirage_crypto_rng.generate n
 
 let random n =
-  Cstruct.to_string (random_buffer n)
+  random_buffer n