1*3f982cf4SFabien Sanglard // Copyright 2019 The Chromium Authors. All rights reserved.
2*3f982cf4SFabien Sanglard // Use of this source code is governed by a BSD-style license that can be
3*3f982cf4SFabien Sanglard // found in the LICENSE file.
4*3f982cf4SFabien Sanglard
5*3f982cf4SFabien Sanglard #include "util/crypto/digest_sign.h"
6*3f982cf4SFabien Sanglard
7*3f982cf4SFabien Sanglard namespace openscreen {
8*3f982cf4SFabien Sanglard
SignData(const EVP_MD * digest,EVP_PKEY * private_key,absl::Span<const uint8_t> data)9*3f982cf4SFabien Sanglard ErrorOr<std::string> SignData(const EVP_MD* digest,
10*3f982cf4SFabien Sanglard EVP_PKEY* private_key,
11*3f982cf4SFabien Sanglard absl::Span<const uint8_t> data) {
12*3f982cf4SFabien Sanglard bssl::ScopedEVP_MD_CTX ctx;
13*3f982cf4SFabien Sanglard if (!EVP_DigestSignInit(ctx.get(), nullptr, digest, nullptr, private_key)) {
14*3f982cf4SFabien Sanglard return Error::Code::kEVPInitializationError;
15*3f982cf4SFabien Sanglard }
16*3f982cf4SFabien Sanglard size_t signature_length = 0;
17*3f982cf4SFabien Sanglard if ((EVP_DigestSign(ctx.get(), nullptr, &signature_length, data.data(),
18*3f982cf4SFabien Sanglard data.size()) != 1) ||
19*3f982cf4SFabien Sanglard signature_length == 0) {
20*3f982cf4SFabien Sanglard return Error::Code::kEVPInitializationError;
21*3f982cf4SFabien Sanglard }
22*3f982cf4SFabien Sanglard
23*3f982cf4SFabien Sanglard std::string signature(signature_length, 0);
24*3f982cf4SFabien Sanglard if (EVP_DigestSign(ctx.get(), reinterpret_cast<uint8_t*>(&signature[0]),
25*3f982cf4SFabien Sanglard &signature_length, data.data(), data.size()) != 1) {
26*3f982cf4SFabien Sanglard return Error::Code::kCreateSignatureFailed;
27*3f982cf4SFabien Sanglard }
28*3f982cf4SFabien Sanglard return signature;
29*3f982cf4SFabien Sanglard }
30*3f982cf4SFabien Sanglard
31*3f982cf4SFabien Sanglard } // namespace openscreen
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