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這是關於如何創建S3預共享URL簽名V4的示例代碼。 填充這些值：如何創建S3預共享url
- bucketName
- 的keyName
- 區域
- secondsToExpire
- ACCESSKEY
- 祕密密鑰
- amzDate
和呼叫噸他生成（）方法。
package com.github.ttwd80.ming;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.nio.charset.Charset;
import java.security.InvalidKeyException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
public class PreShareUrl {
private String bucketName;
private String keyName;
private String region;
private int secondsToExpire;
private String accessKey;
private String secretKey;
private String amzDate;
public String getBucketName() {
return bucketName;
}
public void setBucketName(String bucketName) {
this.bucketName = bucketName;
}
public String getKeyName() {
return keyName;
}
public void setKeyName(String keyName) {
this.keyName = keyName;
}
public String getRegion() {
return region;
}
public void setRegion(String region) {
this.region = region;
}
public int getSecondsToExpire() {
return secondsToExpire;
}
public void setSecondsToExpire(int secondsToExpire) {
this.secondsToExpire = secondsToExpire;
}
public String getAccessKey() {
return accessKey;
}
public void setAccessKey(String accessKey) {
this.accessKey = accessKey;
}
public String getSecretKey() {
return secretKey;
}
public void setSecretKey(String secretKey) {
this.secretKey = secretKey;
}
public String getAmzDate() {
return amzDate;
}
public void setAmzDate(String amzDate) {
this.amzDate = amzDate;
}
public String generate() throws UnsupportedEncodingException, NoSuchAlgorithmException, InvalidKeyException {
StringBuilder sb = new StringBuilder();
sb.append("https://");
sb.append(createHost());
sb.append("/");
sb.append(keyName);
sb.append("?");
sb.append("X-Amz-Algorithm=AWS4-HMAC-SHA256");
sb.append("&");
sb.append("X-Amz-Date=");
sb.append(amzDate);
sb.append("&");
sb.append("X-Amz-SignedHeaders=host");
sb.append("&");
sb.append("X-Amz-Expires=");
sb.append(secondsToExpire);
sb.append("&");
sb.append("X-Amz-Credential=");
sb.append(URLEncoder.encode(createCredential(), "UTF-8"));
sb.append("&");
sb.append("X-Amz-Signature=");
sb.append(calculate());
return sb.toString();
}
private String createHost() {
StringBuilder sb = new StringBuilder();
sb.append(bucketName);
sb.append(".s3-");
sb.append(region);
sb.append(".amazonaws.com");
return sb.toString();
}
private String createCredential() {
StringBuilder sb = new StringBuilder();
sb.append(accessKey);
sb.append("/");
sb.append(createCredentialScope());
return sb.toString();
}
private String calculate() throws UnsupportedEncodingException, NoSuchAlgorithmException, InvalidKeyException {
String canonicalRequest = createCanonicalRequest();
System.out.println("canonicalRequest");
System.out.println(canonicalRequest);
String stringToSign = createStringToSign(canonicalRequest);
System.out.println(stringToSign);
byte[] signingKey = newSigningKey(secretKey, amzDate.substring(0, 8), region, "s3");
System.out.println(bytesToHex(signingKey));
byte[] signature = sign(stringToSign.getBytes(Charset.forName("UTF-8")), signingKey, "HmacSHA256");
return bytesToHex(signature);
}
private String createStringToSign(String canonicalRequest) throws NoSuchAlgorithmException {
StringBuilder sb = new StringBuilder();
sb.append("AWS4-HMAC-SHA256");
sb.append("\n");
sb.append(amzDate);
sb.append("\n");
sb.append(createCredentialScope());
sb.append("\n");
String hashedCanonicalRequest = bytesToHex(doHash(canonicalRequest));
sb.append(hashedCanonicalRequest);
return sb.toString();
}
private String createCredentialScope() {
StringBuilder sb = new StringBuilder();
sb.append(amzDate.substring(0, 8));
sb.append("/");
sb.append(region);
sb.append("/");
sb.append("s3");
sb.append("/");
sb.append("aws4_request");
return sb.toString();
}
private String createCanonicalRequest() throws UnsupportedEncodingException {
String contentSha256 = "UNSIGNED-PAYLOAD";
StringBuilder sb = new StringBuilder();
sb.append("GET");
sb.append("\n");
sb.append("/");
sb.append(keyName);
sb.append("\n");
sb.append("X-Amz-Algorithm=AWS4-HMAC-SHA256");
sb.append("&");
sb.append("X-Amz-Credential=");
sb.append(URLEncoder.encode(createCredential(), "UTF-8"));
sb.append("&");
sb.append("X-Amz-Date=");
sb.append(amzDate);
sb.append("&");
sb.append("X-Amz-Expires=");
sb.append(secondsToExpire);
sb.append("&");
sb.append("X-Amz-SignedHeaders=host");
sb.append("\n");
sb.append("host:");
sb.append(createHost());
sb.append("\n");
sb.append("\n");
sb.append("host");
sb.append("\n");
sb.append(contentSha256);
return sb.toString();
}
private byte[] doHash(String text) throws NoSuchAlgorithmException {
MessageDigest md = MessageDigest.getInstance("SHA-256");
md.update(text.getBytes(Charset.forName("UTF-8")));
return md.digest();
}
public static String bytesToHex(byte[] bytes) {
final char[] hexArray = "abcdef".toCharArray();
char[] hexChars = new char[bytes.length * 2];
for (int j = 0; j < bytes.length; j++) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return new String(hexChars);
}
private byte[] newSigningKey(String secretKey, String dateStamp, String regionName, String serviceName)
throws InvalidKeyException, NoSuchAlgorithmException {
byte[] kSecret = ("AWS4" + secretKey).getBytes(Charset.forName("UTF-8"));
byte[] kDate = sign(dateStamp.getBytes(), kSecret, "HmacSHA256");
byte[] kRegion = sign(regionName.getBytes(), kDate, "HmacSHA256");
byte[] kService = sign(serviceName.getBytes(), kRegion, "HmacSHA256");
return sign("aws4_request".getBytes(), kService, "HmacSHA256");
}
protected byte[] sign(byte[] data, byte[] key, String algorithm)
throws NoSuchAlgorithmException, InvalidKeyException {
Mac mac = Mac.getInstance(algorithm.toString());
mac.init(new SecretKeySpec(key, algorithm.toString()));
return mac.doFinal(data);
}
}