To provide credentials for AWS Version 2 authentication, you use the Authorization request header with a value in the format shown below:
Authorization: AWS access-key:signature
In this format:
- access-key
- The Base64-encoded username for your user account.
- signature
- A value calculated using your secret key and specific elements of the S3 compatible request, including the date and time of the request. Your secret key is the MD5-hashed password for your user account.
- Because the signature for an S3 compatible request is based on the request contents, it differs for different requests.
Here’s an example of an Authorization header for AWS Version 2 authentication:
Authorization: AWS bGdyZWVu:vQ/rj3y0AUjWsht9M5aQw4+D0dA=
With AWS Version 4 authentication, the S3 compatible API supports both signed and unsigned payloads.