AWS S3 with Authentication¶
When using Amazon S3 for remote storage, it might be required to secure access to the S3 buckets instead of using 'public' access. This means that the requests to the content in the bucket must be authenticated. See Using S3 storage regarding configuring Amazon S3 storage.
There are two ways to do this:
- use the Authorization header
- send a signature as a URL-encoded query-string parameter.
mod_unified_s3_auth module supports both.
More information can be found in Amazon's Authenticating Requests documentation.
It is possible to use webserver directives and let USP sign the request automatically with the following webserver directives.
This covers one specific use case: both content (mp4/ismv) and server manifest (ism) are placed in the S3 bucket and the manifest references the content locally (no paths or URLs, just the filename).
The directives for Apache are the following:
|S3SecretKey||The AWS secret key.|
|S3AccessKey||The AWS access key.|
|S3Region||Region of bucket where data is stored, added in 1.7.29. Required for AWS Signature v4.|
|S3UseHeaders||Set to 'on' to use HTTP headers for AWS authentication, instead of query parameters.|
The keys can be created in the AWS IAM portal and managed there as well (active/inactive, delete).
AWS Signature v4¶
As of January 30, 2014, newer AWS regions such as eu-central-1 require the use of the AWS Signature v4 for authentication. To enable the use of v4 signatures the name of the S3 region must be set when configuring access to the bucket. If the region is set, v4 signatures will be used whether or not the region requires it. Not setting the S3 region will result in USP using the older v2 signature method that may not be supported by all regions.
To secure access to Amazon S3 buckets,
<Proxy> sections are the appropriate
locations to specify the S3 authentication directives.
The directives can appear in two places:
- In a
<Proxy>section. This is the recommended location.
- In a
<Location>section, which is used in combination with the
IsmProxyPassdirective in a
<Location>section. This is the traditional way of specifying the S3 parameters, and it is still supported for backwards compatibility.
Each Amazon S3 bucket must have its own
<Proxy> section. These are then used
automatically for each request sent to the Amazon S3 bucket.
An additional benefit for using
<Proxy> sections is that performance is
improved by keeping the connections to Amazon S3 bucket alive.
For example, if the bucket is called
mybucket, and it is hosted in Amazon's
eu-central-1 region, the section becomes:
<Proxy "http://mybucket.s3-eu-central-1.amazonaws.com/"> S3SecretKey SECRET_KEY S3AccessKey ACCESS_KEY S3Region eu-central-1 S3UseHeaders on ProxySet connectiontimeout=5 enablereuse=on keepalive=on retry=0 timeout=30 ttl=300 </Proxy>
This can be used both when your manifests and/or media files are directly
referring to Amazon S3 buckets, and when
IsmProxyPass directives redirect
requests to Amazon S3 buckets, see Object Storage Use Cases for an
outline of the different use cases.
In this case, there is no need to add any S3 parameters to the sections
Schematically, it works like the following:
player --> cdn --> shield-cache --> origin (mod-smooth-streaming) --> signing (mod_unified_s3_auth) --> s3
S3UseHeaders setting determines how the information is shared, either by
adding a number of additional request headers, or otherwise by adding a number
of additional query arguments.
Following is a complete example
<VirtualHost *:80> ServerName www.example.com DocumentRoot /var/www/mysite # Enable just in time packaging for VOD and using subrequests for I/O backend requests. <Location "/"> UspHandleIsm on UspEnableSubreq on IsmProxyPass https://mybucket.s3-eu-central-1.amazonaws.com/ </Location> # If proxying to SSL hosts is desired, you must turn on SSLProxyEngine. SSLProxyEngine on <Proxy "https://mybucket.s3-eu-central-1.amazonaws.com/"> S3SecretKey SECRET_KEY S3AccessKey ACCESS_KEY S3Region eu-central-1 S3UseHeaders on ProxySet connectiontimeout=5 enablereuse=on keepalive=on retry=0 timeout=30 ttl=300 </Proxy> </VirtualHost>
Legacy IsmProxyPass Example¶
In previous versions of Origin, when subrequests were not available, S3
authentication parameters were typically placed in a
with a corresponding
<Directory> section containing an
<Location /s3/> S3SecretKey SECRET_KEY S3AccessKey ACCESS_KEY S3Region eu-west-1 </Location> <Directory /var/www/mysite/s3/> IsmProxyPass https://mybucket.s3-eu-west-1.amazonaws.com/ </Directory>
DocumentRoot of the site is
/var/www/mysite, the URI path
/s3/example.ism would be mapped by
https://mybucket.s3-eu-west-1.amazonaws.com/example.ism, and the
S3Region parameters from the
<Location> section would be used for authentication.