Wasm runtime: BLAKE2b implementation

Co-authored-by: Ricky Vetter <rickywvetter@gmail.com>

Author: vouillon

CHANGES.md

@@ -10,6 +10,7 @@
 * Runtime: update constant imports to use `node:fs` module (#1850)
 * Runtime: make Obj.dup work with floats and boxed numbers (#1871)
 * Lib: make the Wasm version of Json.output work with native ints and JavaScript objects (#1872)
+* Runtime: implement BLAKE2b primitives for Wasm (#1873)
 
 ## Bug fixes
 * Runtime: fix path normalization (#1848)

compiler/tests-check-prim/main.5.3.output

@@ -27,6 +27,11 @@ caml_bigstring_blit_string_to_ba
 caml_bigstring_memcmp
 caml_hash_mix_bigstring
 
+From +blake2.js:
+blake2_js_for_wasm_create
+blake2_js_for_wasm_final
+blake2_js_for_wasm_update
+
 From +effect.js:
 jsoo_effect_not_supported
 

compiler/tests-check-prim/unix-Unix.5.3.output

@@ -103,6 +103,11 @@ caml_bigstring_blit_string_to_ba
 caml_bigstring_memcmp
 caml_hash_mix_bigstring
 
+From +blake2.js:
+blake2_js_for_wasm_create
+blake2_js_for_wasm_final
+blake2_js_for_wasm_update
+
 From +effect.js:
 jsoo_effect_not_supported
 

compiler/tests-check-prim/unix-Win32.5.3.output

@@ -76,6 +76,11 @@ caml_bigstring_blit_string_to_ba
 caml_bigstring_memcmp
 caml_hash_mix_bigstring
 
+From +blake2.js:
+blake2_js_for_wasm_create
+blake2_js_for_wasm_final
+blake2_js_for_wasm_update
+
 From +effect.js:
 jsoo_effect_not_supported
 

compiler/tests-ocaml/lib-digest/dune

@@ -10,5 +10,4 @@
  (build_if
   (>= %{ocaml_version} 5.2))
  (modules digests)
- ; blake2b not supported by wasm_of_ocaml yet
- (modes js))
+ (modes js wasm))

runtime/js/blake2.js

@@ -379,3 +379,34 @@ function caml_blake2_bytes(hashlen, key, buf, ofs, len) {
   caml_blake2_update(ctx, buf, ofs, len);
   return caml_blake2_final(ctx, hashlen);
 }
+
+//Provides: blake2_js_for_wasm_create
+//Requires: caml_blake2_create, caml_string_of_jsbytes
+//Version: >= 5.2
+function blake2_js_for_wasm_create(hashlen, key) {
+  const key_jsoo_string = caml_string_of_jsbytes(key);
+  return caml_blake2_create(hashlen, key_jsoo_string);
+}
+
+//Provides: blake2_js_for_wasm_final
+//Requires: caml_blake2_final, caml_jsbytes_of_string
+//Version: >= 5.2
+function blake2_js_for_wasm_final(ctx, hashlen) {
+  return caml_jsbytes_of_string(caml_blake2_final(ctx, hashlen));
+}
+
+//Provides: blake2_js_for_wasm_update
+//Requires: caml_blake2_update, caml_bytes_of_jsbytes
+//Version: >= 5.2, < 5.3
+function blake2_js_for_wasm_update(ctx, buf, ofs, len) {
+  const buf_jsoo_string = caml_string_of_jsbytes(buf);
+  return caml_blake2_update(ctx, buf_jsoo_string, ofs, len);
+}
+
+//Provides: blake2_js_for_wasm_update
+//Requires: caml_blake2_update, caml_bytes_of_jsbytes
+//Version: >= 5.3
+function blake2_js_for_wasm_update(ctx, buf, ofs, len) {
+  const buf_jsoo_string = caml_bytes_of_jsbytes(buf);
+  return caml_blake2_update(ctx, buf_jsoo_string, ofs, len);
+}

runtime/wasm/blake2.wat

@@ -0,0 +1,90 @@
+(module
+(@if (>= ocaml_version (5 2 0))
+(@then
+   (import "jslib" "wrap" (func $wrap (param anyref) (result (ref eq))))
+   (import "jslib" "unwrap" (func $unwrap (param (ref eq)) (result anyref)))
+   (import "jslib" "caml_string_of_jsbytes"
+      (func $caml_string_of_jsbytes (param (ref eq)) (result (ref eq))))
+   (import "jslib" "caml_jsbytes_of_string"
+      (func $caml_jsbytes_of_string (param (ref eq)) (result (ref eq))))
+
+   (import "js" "blake2_js_for_wasm_create"
+      (func $blake2_js_for_wasm_create (param (ref eq) anyref) (result anyref)))
+
+   (import "js" "blake2_js_for_wasm_update"
+      (func $blake2_js_for_wasm_update (param anyref anyref i32 i32)))
+
+   (import "js" "blake2_js_for_wasm_string"
+      (func $blake2_js_for_wasm_string
+         (param (ref eq) anyref anyref i32 i32) (result anyref)))
+
+   (import "js" "blake2_js_for_wasm_final"
+      (func $blake2_js_for_wasm_final (param anyref (ref eq)) (result anyref)))
+
+   (type $bytes (array (mut i8)))
+
+   (func (export "caml_blake2_create")
+      (param $hashlen (ref eq)) (param $key (ref eq)) (result (ref eq))
+      (return_call $wrap
+         (call $blake2_js_for_wasm_create
+            (local.get $hashlen)
+            (call $unwrap (call $caml_jsbytes_of_string (local.get $key))))))
+
+   (func $jsbytes_of_substring
+      (param $vbuf (ref eq)) (param $vofs (ref eq)) (param $vlen (ref eq))
+      (result anyref i32 i32)
+      (local $buf (ref $bytes)) (local $buf' (ref $bytes))
+      (local $ofs i32) (local $len i32)
+      (local.set $buf (ref.cast (ref $bytes) (local.get $vbuf)))
+      (local.set $ofs (i31.get_u (ref.cast (ref i31) (local.get $vofs))))
+      (local.set $len (i31.get_u (ref.cast (ref i31) (local.get $vlen))))
+      ;; We copy the relevant part of the buffer if we only use a small portion
+      (if (i32.le_u (i32.shl (local.get $len) (i32.const 1))
+             (array.len (local.get $buf)))
+         (then
+            (local.set $buf' (array.new $bytes (i32.const 0) (local.get $len)))
+            (array.copy $bytes $bytes
+               (local.get $buf') (i32.const 0)
+               (local.get $buf) (local.get $ofs) (local.get $len))
+            (local.set $buf (local.get $buf'))
+            (local.set $ofs (i32.const 0))))
+      (tuple.make 3
+         (call $unwrap (call $caml_jsbytes_of_string (local.get $buf)))
+         (local.get $ofs)
+         (local.get $len)))
+
+   (func (export "caml_blake2_update")
+      (param $ctx (ref eq)) (param $buf (ref eq)) (param $ofs (ref eq))
+      (param $len (ref eq)) (result (ref eq))
+      (call $blake2_js_for_wasm_update
+         (call $unwrap (local.get $ctx))
+         (call $jsbytes_of_substring
+            (local.get $buf) (local.get $ofs) (local.get $len)))
+      (ref.i31 (i32.const 0)))
+
+   (func (export "caml_blake2_final")
+      (param $ctx (ref eq)) (param $hashlen (ref eq)) (result (ref eq))
+      (return_call $caml_string_of_jsbytes
+         (call $wrap
+            (call $blake2_js_for_wasm_final
+               (call $unwrap (local.get $ctx))
+               (local.get $hashlen)))))
+
+   (func (export "caml_blake2_string") (export "caml_blake2_bytes")
+      (param $hashlen (ref eq)) (param $key (ref eq)) (param $buf (ref eq))
+      (param $ofs (ref eq)) (param $len (ref eq)) (result (ref eq))
+      (local $ctx anyref)
+      (local.set $ctx
+         (call $blake2_js_for_wasm_create
+            (local.get $hashlen)
+            (call $unwrap (call $caml_jsbytes_of_string (local.get $key)))))
+      (call $blake2_js_for_wasm_update
+         (local.get $ctx)
+         (call $jsbytes_of_substring
+            (local.get $buf) (local.get $ofs) (local.get $len)))
+      (return_call $caml_string_of_jsbytes
+         (call $wrap
+            (call $blake2_js_for_wasm_final
+               (local.get $ctx) (local.get $hashlen)))))
+))
+)