From ed7666b445666a57f938e7e55c08975fbea3246e Mon Sep 17 00:00:00 2001
From: Claudio DeSouza <cdesouza@brave.com>
Date: Sat, 12 Jul 2025 05:46:38 +0100
Subject: [PATCH] [cr140] `SignatureCreator` deleted

This change removes the only use in Brave for `SignatureCreator`, and
replaces it with `crypto::sign::Sign`.

Chromium changes:
https://chromium.googlesource.com/chromium/src/+/cb74f0799e82a75b96c414272adbeddf48db0a6b
https://chromium.googlesource.com/chromium/src/+/7e517f85c0974949ee096e089e65dcdd8173f587

commit cb74f0799e82a75b96c414272adbeddf48db0a6b
Author: Elly <ellyjones@chromium.org>
Date:   Tue Jul 8 20:24:53 2025 -0700

    crypto: get rid of SignatureCreator

    All the remaining deps on it are gone now.

    Bug: 406190025
    Change-Id: I10b9f37007c5308b98b64c02756d9d382eb1d838
    Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6711257
    Reviewed-by: David Benjamin <davidben@chromium.org>
    Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
    Commit-Queue: Elly FJ <ellyjones@chromium.org>
    Reviewed-by: Sergey Poromov <poromov@chromium.org>
    Cr-Commit-Position: refs/heads/main@{#1484137}

commit 7e517f85c0974949ee096e089e65dcdd8173f587
Author: Elly <ellyjones@chromium.org>
Date:   Thu Jul 3 08:33:14 2025 -0700

    components/policy: stop using SignatureCreator

    Instead, use crypto::sign::Sign(), which is functionally identical but
    not deprecated.

    Bug: 428657808
    Change-Id: I50ffd6a84d31bd34221302c38c177ac7948954a0
    Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6692471
    Commit-Queue: Elly FJ <ellyjones@chromium.org>
    Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
    Cr-Commit-Position: refs/heads/main@{#1482292}
---
 components/web_discovery/browser/rsa.cc | 22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/components/web_discovery/browser/rsa.cc b/components/web_discovery/browser/rsa.cc
index 9b9dbaffa2e..ebf5c485f5e 100644
--- a/components/web_discovery/browser/rsa.cc
+++ b/components/web_discovery/browser/rsa.cc
@@ -11,8 +11,9 @@
 #include "base/base64.h"
 #include "base/check.h"
 #include "base/threading/thread_restrictions.h"
+#include "crypto/keypair.h"
 #include "crypto/rsa_private_key.h"
-#include "crypto/signature_creator.h"
+#include "crypto/sign.h"
 
 namespace web_discovery {
 
@@ -81,20 +82,11 @@ std::optional<std::string> RSASign(crypto::RSAPrivateKey* key,
   base::AssertLongCPUWorkAllowed();
   CHECK(key);
 
-  std::vector<uint8_t> signature;
-  auto signature_creator = crypto::SignatureCreator::Create(
-      key, crypto::SignatureCreator::HashAlgorithm::SHA256);
-  if (!signature_creator) {
-    return std::nullopt;
-  }
-  if (!signature_creator->Update(message.data(), message.size())) {
-    return std::nullopt;
-  }
-  if (!signature_creator->Final(&signature)) {
-    return std::nullopt;
-  }
-
-  return base::Base64Encode(signature);
+  auto wrapped_key =
+      crypto::keypair::PrivateKey::FromDeprecatedRSAPrivateKey(key);
+  std::vector<uint8_t> signature_bytes = crypto::sign::Sign(
+      crypto::sign::SignatureKind::RSA_PKCS1_SHA256, wrapped_key, message);
+  return base::Base64Encode(signature_bytes);
 }
 
 }  // namespace web_discovery