AWS S3 access denied when getting image by url

Question

I am working on AWS EC2 Ubuntu Machine and trying to fetch image from AWS S3 but following error has been shown to me every time.

<Error>
<Code>InvalidArgument</Code>
<Message>
Requests specifying Server Side Encryption with AWS KMS managed keys require AWS Signature Version 4.
</Message>
<ArgumentName>Authorization</ArgumentName>
<ArgumentValue>null</ArgumentValue>
<RequestId>7C8B4BF1CE2FDC9E</RequestId>
<HostId>
/L5kjuOET4XFgGter2eFHX+aRSvVm/7VVmIBqQE/oMLeQZ1ditSMZuHPOlsMaKi8hYRnGilTqZY=
</HostId>
</Error>

Here is my bucket policy

{
 "Version": "2012-10-17",
 "Id": "Policy1441213815928",
 "Statement": [
  {
   "Sid": "Stmt1441213813464",
   "Effect": "Allow",
   "Principal": "*",
   "Action": "s3:GetObject",
   "Resource": "arn:aws:s3:::mytest.sample/*"
  }
 ]
}

Here is the code

require 'aws-autoloader.php';

$credentials = new Aws\Credentials\Credentials('key', 'key');
$bucketName = "mytest.sample";
$s3 = new Aws\S3\S3Client([
    'signature' => 'v4',
    'version' => 'latest',
    'region' => 'ap-southeast-1',
    'credentials' => $credentials,
    'http' => [
        'verify' => '/home/ubuntu/cacert.pem'
    ],
    'Statement' => [
        'Action ' => "*",
    ],

  ]);

$result = $s3->getObject(array(
'Bucket' => $bucketName,
'Key' => 'about_us.jpg',
    ));

Html

<img src="<?php echo $result['@metadata']['effectiveUri']; ?>" />

Edit for Michael - sqlbot : here I am using default KMS.

   try {
        $result = $this->Amazon->S3->putObject(array(
            'Bucket' => 'mytest.sample',
            'ACL' => 'authenticated-read',
            'Key' =>  $newfilename,
            'ServerSideEncryption' => 'aws:kms',
            'SourceFile' => $filepath,
            'ContentType' => mime_content_type($filepath),
            'debug' => [
                'logfn' => function ($msg) {
                    echo $msg . "\n";
                },
                'stream_size' => 0,
                'scrub_auth' => true,
                'http' => true,
            ],
        ));
    } catch (S3Exception $e) {
        echo $e->getMessage() . "\n";
    }

let me know if you need more.

Answer 1

PHP sdk v2

1. the Credentials package is Aws\Common\Credentials
2. to create an S3Client you need a factory

Try something like this

use Aws\S3\S3Client;
use Aws\Common\Credentials\Credentials;

$credentials = new Credentials('YOUR_ACCESS_KEY', 'YOUR_SECRET_KEY');

// Instantiate the S3 client with your AWS credentials
$s3Client = S3Client::factory(array(
    'signature' => 'v4',
    'region' => 'ap-southeast-1',
    'credentials' => $credentials,
    .....
  ]);
)

If that does not work you might try to declare explicitly a SignatureV4 object

use Aws\S3\S3Client;
use Aws\Common\Credentials\Credentials;
use Aws\Common\Signature\SignatureV4;

$credentials = new Credentials('YOUR_ACCESS_KEY', 'YOUR_SECRET_KEY');

// Instantiate the S3 client with your AWS credentials
$s3Client = S3Client::factory(array(
    'signature' => new SignatureV4(),
    'region' => 'ap-southeast-1',
    'credentials' => $credentials,
    .....
  ]);
)

In case you upgrade to sdk v3

1. You need to have signature_version (instead of signature) as parameter when you declare your s3 client
2. Statement does not appear to be a valid parameter (http://docs.aws.amazon.com/aws-sdk-php/v3/guide/guide/configuration.html#signature-version)
3. if issue you can turn on debug param to get more output

This would look like this

$s3 = new Aws\S3\S3Client([
    'signature_version' => 'v4',
    'version' => 'latest',
    'region' => 'ap-southeast-1',
    'credentials' => $credentials,
    'http' => [
        'verify' => '/home/ubuntu/cacert.pem'
    ],
    'debug'   => true

  ]);

see here for the full list of available parameter

Answer 2

I have also face this issue with aws:kms encyrption key, I suggest that if you wanted to use kms key then you have to create your kms key in IAM section of AWS Console. I love to recommended AES256 server side encryption, here S3 automatically Encrypted your data while putting and decryption while getting object. Please go through below link: S3 Server Side encryption with AES256

My Solution is change this line 'ServerSideEncryption' => 'aws:kms' with 'ServerSideEncryption' => 'AES256'

 try {
    $result = $this->Amazon->S3->putObject(array(
        'Bucket' => 'mytest.sample',
        'ACL' => 'authenticated-read',
        'Key' =>  $newfilename,
        'ServerSideEncryption' => 'AES256',
        'SourceFile' => $filepath,
        'ContentType' => mime_content_type($filepath),
        'debug' => [
            'logfn' => function ($msg) {
                echo $msg . "\n";
            },
            'stream_size' => 0,
            'scrub_auth' => true,
            'http' => true,
        ],
    ));
} catch (S3Exception $e) {
    echo $e->getMessage() . "\n";
}

Please also update your bucket policy with below json, it will prevent you to upload object with out AES256 encryption

{
        "Sid": "DenyUnEncryptedObjectUploads",
        "Effect": "Deny",
        "Principal": "*",
        "Action": "s3:PutObject",
        "Resource": "arn:aws:s3:::yourbucketname/*",
        "Condition": {
            "StringNotEquals": {
                "s3:x-amz-server-side-encryption": "AES256"
            }
        }
    }