software.amazon.awssdk.auth.signer.internal.AbstractAwsSigner Maven / Gradle / Ivy
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/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed
* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
package software.amazon.awssdk.auth.signer.internal;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.security.DigestInputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import software.amazon.awssdk.annotations.SdkInternalApi;
import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.AwsCredentials;
import software.amazon.awssdk.auth.credentials.AwsSessionCredentials;
import software.amazon.awssdk.core.checksums.SdkChecksum;
import software.amazon.awssdk.core.exception.SdkClientException;
import software.amazon.awssdk.core.io.SdkDigestInputStream;
import software.amazon.awssdk.core.signer.Signer;
import software.amazon.awssdk.http.ContentStreamProvider;
import software.amazon.awssdk.http.SdkHttpFullRequest;
import software.amazon.awssdk.utils.BinaryUtils;
import software.amazon.awssdk.utils.StringUtils;
/**
* Abstract base class for AWS signing protocol implementations. Provides
* utilities commonly needed by signing protocols such as computing
* canonicalized host names, query string parameters, etc.
*
* Not intended to be sub-classed by developers.
*/
@SdkInternalApi
public abstract class AbstractAwsSigner implements Signer {
private static final ThreadLocal SHA256_MESSAGE_DIGEST;
static {
SHA256_MESSAGE_DIGEST = ThreadLocal.withInitial(() -> {
try {
return MessageDigest.getInstance("SHA-256");
} catch (NoSuchAlgorithmException e) {
throw SdkClientException.builder()
.message("Unable to get SHA256 Function" + e.getMessage())
.cause(e)
.build();
}
});
}
private static byte[] doHash(String text) throws SdkClientException {
try {
MessageDigest md = getMessageDigestInstance();
md.update(text.getBytes(StandardCharsets.UTF_8));
return md.digest();
} catch (Exception e) {
throw SdkClientException.builder()
.message("Unable to compute hash while signing request: " + e.getMessage())
.cause(e)
.build();
}
}
/**
* Returns the re-usable thread local version of MessageDigest.
*/
private static MessageDigest getMessageDigestInstance() {
MessageDigest messageDigest = SHA256_MESSAGE_DIGEST.get();
messageDigest.reset();
return messageDigest;
}
/**
* Computes an RFC 2104-compliant HMAC signature and returns the result as a
* Base64 encoded string.
*/
protected String signAndBase64Encode(String data, String key,
SigningAlgorithm algorithm) throws SdkClientException {
return signAndBase64Encode(data.getBytes(StandardCharsets.UTF_8), key, algorithm);
}
/**
* Computes an RFC 2104-compliant HMAC signature for an array of bytes and
* returns the result as a Base64 encoded string.
*/
private String signAndBase64Encode(byte[] data, String key,
SigningAlgorithm algorithm) throws SdkClientException {
try {
byte[] signature = sign(data, key.getBytes(StandardCharsets.UTF_8), algorithm);
return BinaryUtils.toBase64(signature);
} catch (Exception e) {
throw SdkClientException.builder()
.message("Unable to calculate a request signature: " + e.getMessage())
.cause(e)
.build();
}
}
protected byte[] signWithMac(String stringData, Mac mac) {
try {
return mac.doFinal(stringData.getBytes(StandardCharsets.UTF_8));
} catch (Exception e) {
throw SdkClientException.builder()
.message("Unable to calculate a request signature: " + e.getMessage())
.cause(e)
.build();
}
}
protected byte[] sign(String stringData, byte[] key,
SigningAlgorithm algorithm) throws SdkClientException {
try {
byte[] data = stringData.getBytes(StandardCharsets.UTF_8);
return sign(data, key, algorithm);
} catch (Exception e) {
throw SdkClientException.builder()
.message("Unable to calculate a request signature: " + e.getMessage())
.cause(e)
.build();
}
}
protected byte[] sign(byte[] data, byte[] key, SigningAlgorithm algorithm) throws SdkClientException {
try {
Mac mac = algorithm.getMac();
mac.init(new SecretKeySpec(key, algorithm.toString()));
return mac.doFinal(data);
} catch (Exception e) {
throw SdkClientException.builder()
.message("Unable to calculate a request signature: " + e.getMessage())
.cause(e)
.build();
}
}
/**
* Hashes the string contents (assumed to be UTF-8) using the SHA-256
* algorithm.
*
* @param text The string to hash.
* @return The hashed bytes from the specified string.
* @throws SdkClientException If the hash cannot be computed.
*/
static byte[] hash(String text) throws SdkClientException {
return AbstractAwsSigner.doHash(text);
}
byte[] hash(InputStream input, SdkChecksum sdkChecksum) throws SdkClientException {
try {
MessageDigest md = getMessageDigestInstance();
@SuppressWarnings("resource")
DigestInputStream digestInputStream = new SdkDigestInputStream(
input, md, sdkChecksum);
byte[] buffer = new byte[1024];
while (digestInputStream.read(buffer) > -1) {
;
}
return digestInputStream.getMessageDigest().digest();
} catch (Exception e) {
throw SdkClientException.builder()
.message("Unable to compute hash while signing request: " + e.getMessage())
.cause(e)
.build();
}
}
/**
* Hashes the binary data using the SHA-256 algorithm.
*
* @param data The binary data to hash.
* @param sdkChecksum Checksum Instance which gets updated as data is read while hashing.
* @return The hashed bytes from the specified data.
* @throws SdkClientException If the hash cannot be computed.
*/
byte[] hash(byte[] data, SdkChecksum sdkChecksum) throws SdkClientException {
try {
MessageDigest md = getMessageDigestInstance();
md.update(data);
if (sdkChecksum != null) {
sdkChecksum.update(data);
}
return md.digest();
} catch (Exception e) {
throw SdkClientException.builder()
.message("Unable to compute hash while signing request: " + e.getMessage())
.cause(e)
.build();
}
}
/**
* Hashes the binary data using the SHA-256 algorithm.
*
* @param data The binary data to hash.
* @return The hashed bytes from the specified data.
* @throws SdkClientException If the hash cannot be computed.
*/
byte[] hash(byte[] data) throws SdkClientException {
return hash(data, null);
}
protected InputStream getBinaryRequestPayloadStream(ContentStreamProvider streamProvider) {
try {
if (streamProvider == null) {
return new ByteArrayInputStream(new byte[0]);
}
return streamProvider.newStream();
} catch (SdkClientException e) {
throw e;
} catch (Exception e) {
throw SdkClientException.builder()
.message("Unable to read request payload to sign request: " + e.getMessage())
.cause(e)
.build();
}
}
/**
* Loads the individual access key ID and secret key from the specified credentials, trimming any extra whitespace from the
* credentials.
*
* Returns either a {@link AwsSessionCredentials} or a {@link AwsBasicCredentials} object, depending on the input type.
*
* @return A new credentials object with the sanitized credentials.
*/
protected AwsCredentials sanitizeCredentials(AwsCredentials credentials) {
String accessKeyId = StringUtils.trim(credentials.accessKeyId());
String secretKey = StringUtils.trim(credentials.secretAccessKey());
if (credentials instanceof AwsSessionCredentials) {
AwsSessionCredentials sessionCredentials = (AwsSessionCredentials) credentials;
return AwsSessionCredentials.create(accessKeyId,
secretKey,
StringUtils.trim(sessionCredentials.sessionToken()));
}
return AwsBasicCredentials.create(accessKeyId, secretKey);
}
/**
* Adds session credentials to the request given.
*
* @param mutableRequest The request to add session credentials information to
* @param credentials The session credentials to add to the request
*/
protected abstract void addSessionCredentials(SdkHttpFullRequest.Builder mutableRequest,
AwsSessionCredentials credentials);
}