From d9e5a17ab08b0386bbb32c1f0cbdeae876829be9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Damir=20Jeli=C4=87?= <poljar@termina.org.uk>
Date: Tue, 8 Dec 2020 16:17:41 +0100
Subject: [PATCH] crypto: Use a native Rust sha2 implementation to calculate
 the commitment

---
 matrix_sdk_crypto/src/verification/sas/helpers.rs | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/matrix_sdk_crypto/src/verification/sas/helpers.rs b/matrix_sdk_crypto/src/verification/sas/helpers.rs
index 5a85e958..37974d14 100644
--- a/matrix_sdk_crypto/src/verification/sas/helpers.rs
+++ b/matrix_sdk_crypto/src/verification/sas/helpers.rs
@@ -14,9 +14,10 @@
 
 use std::{collections::BTreeMap, convert::TryInto};
 
+use sha2::{Digest, Sha256};
 use tracing::{trace, warn};
 
-use olm_rs::{sas::OlmSas, utility::OlmUtility};
+use olm_rs::sas::OlmSas;
 
 use matrix_sdk_common::{
     api::r0::to_device::DeviceIdOrAllDevices,
@@ -33,6 +34,7 @@ use matrix_sdk_common::{
 
 use crate::{
     identities::{ReadOnlyDevice, UserIdentities},
+    utilities::encode,
     ReadOnlyAccount, ToDeviceRequest,
 };
 
@@ -59,8 +61,11 @@ pub fn calculate_commitment(public_key: &str, content: &StartToDeviceEventConten
         .try_into()
         .expect("Can't canonicalize content");
 
-    let utility = OlmUtility::new();
-    utility.sha256_utf8_msg(&format!("{}{}", public_key, json_content))
+    encode(
+        Sha256::new()
+            .chain(&format!("{}{}", public_key, json_content))
+            .finalize(),
+    )
 }
 
 /// Get a tuple of an emoji and a description of the emoji using a number.