This nginx module can proxy requests to authenticated S3 backends using Amazon's V4 authentication API. The first version of this module was written for the V2 authentication protocol and can be found in the AuthV2 branch.
This fork changes the processing phase to NGX_HTTP_PRECONTENT_PHASE, so subrequests can also use this module to generate authentication headers normally. In addition, some instructions and functions are added according to actual usage needs.
This project uses the same license as ngnix does i.e. the 2 clause BSD / simplified BSD / FreeBSD license
Implements proxying of authenticated requests to S3.
server {
listen 8000;
# aws_auth_convert_head is on by default.
# If you set `proxy_cache_convert_head` to off, or the `proxy_cache` function is not enabled, please also set `aws_auth_convert_head` to off. Otherwise, the HEAD request may be intercepted.
# proxy_cache_convert_head off;
# aws_auth_convert_head off;
# Determine whether to append an authentication header based on the values of multiple variables.
# aws_auth_bypass $http_no_s3_auth $arg_no_s3_auth $cookie_no_s3_auth $http_authorization;
location / {
aws_auth on;
aws_auth_access_key your_aws_access_key; # Example AKIDEXAMPLE
aws_auth_key_scope scope_of_generated_signing_key; #Example 20150830/us-east-1/service/aws4_request
aws_auth_signing_key signing_key_generated_using_script; #Example L4vRLWAO92X5L3Sqk5QydUSdB0nC9+1wfqLMOKLbRp4=
aws_auth_bucket your_s3_bucket;
proxy_pass http://your_s3_bucket.s3.amazonaws.com;
}
# This is an example that does not use the server root for the proxy root
location /myfiles {
rewrite /myfiles/(.*) /$1 break;
proxy_pass http://your_s3_bucket.s3.amazonaws.com/$1;
aws_auth_access_key your_aws_access_key;
aws_auth_key_scope scope_of_generated_signing_key;
aws_auth_signing_key signing_key_generated_using_script;
aws_auth_bucket your_s3_bucket;
}
# This is an example that use specific s3 endpoint, default endpoint is s3.amazonaws.com
location /s3_beijing {
rewrite /s3_beijing/(.*) /$1 break;
proxy_pass http://your_s3_bucket.s3.cn-north-1.amazonaws.com.cn/$1;
aws_auth on;
aws_auth_endpoint s3.cn-north-1.amazonaws.com.cn;
aws_auth_access_key your_aws_access_key;
aws_auth_key_scope scope_of_generated_signing_key;
aws_auth_signing_key signing_key_generated_using_script;
aws_auth_bucket your_s3_bucket;
}
# This is an example that specific upstream host and uri
# Be careful not to use aws_auth_host and aws_auth_bucket + aws_auth_endpoint at the same time, aws_auth_bucket + aws_auth_endpoint will have higher priority.
location /s3_beijing_2 {
set $upstream_host your_s3_bucket.s3.cn-north-1.amazonaws.com.cn;
set $upstream_uri /test.txt;
proxy_pass http://$upstream_host$upstream_uri;
aws_auth on;
aws_auth_host $upstream_host;
aws_auth_uri $upstream_uri;
aws_auth_access_key your_aws_access_key;
aws_auth_key_scope scope_of_generated_signing_key;
aws_auth_signing_key signing_key_generated_using_script;
}
# Security warning: Placing the secret key in the nginx configuration is unsafe. Please give priority to using the script mentioned below to generate and regularly update the signing key. Only use this solution as a last resort.
# This is an example that automatically calculate signing_key and key_scope
location /s3_beijing_3 {
aws_auth on;
aws_auth_access_key your_aws_access_key; # Example AKIDEXAMPLE
aws_auth_secret_key your_aws_secret_key; # Example LTAxxxxxxxx
aws_auth_region cn-north-1;
aws_auth_endpoint s3.cn-north-1.amazonaws.com.cn;
aws_auth_bucket your_s3_bucket;
proxy_pass http://your_s3_bucket.s3.amazonaws.com;
}
}The V4 protocol does not need access to the actual secret keys that one obtains from the IAM service. The correct way to use the IAM key is to actually generate a scoped signing key and use this signing key to access S3. This nginx module requires the signing key and not the actual secret key. It is an insecure practise to let the secret key reside on your nginx server.
Note that signing keys have a validity of just one week. Hence, they need to be refreshed constantly. Please useyour favourite configuration management system such as saltstack, puppet, chef, etc. etc. to distribute the signing keys to your nginx clusters. Do not forget to HUP the server after placing the new signing key as nginx reads the configuration only at startup time.
A standalone python script has been provided to generate the signing key
./generate_signing_key -h
usage: generate_signing_key [-h] -k SECRET_KEY -r REGION [-s SERVICE]
[-d DATE] [--no-base64] [-v]
Generate AWS S3 signing key in it's base64 encoded form
optional arguments:
-h, --help show this help message and exit
-k SECRET_KEY, --secret-key SECRET_KEY
The secret key generated using AWS IAM. Do not confuse
this with the access key id
-r REGION, --region REGION
The AWS region where this key would be used. Example:
us-east-1
-s SERVICE, --service SERVICE
The AWS service for which this key would be used.
Example: s3
-d DATE, --date DATE The date on which this key is generated in yyyymmdd
format
--no-base64 Disable output as a base64 encoded string. This NOT
recommended
-v, --verbose Produce verbose output on stderr
./generate_signing_key -k wJalrXUtnFEMI/K7MDENG+bPxRfiCYEXAMPLEKEY -r us-east-1
L4vRLWAO92X5L3Sqk5QydUSdB0nC9+1wfqLMOKLbRp4=
20160902/us-east-1/s3/aws4_request
This plugin is tested against a variety of nginx versions, compilers, OS versions and hardware architectures. Take a look at the .travis.yml file or the latest travis build status to see the versions that the plugin has been tested against
The 2.x version of the module currently only has support for GET and HEAD calls. This is because signing request body is complex and has not yet been implemented.
Original idea based on http://nginx.org/pipermail/nginx/2010-February/018583.html and suggestion of moving to variables rather than patching the proxy module.
Subsequent contributions can be found in the commit logs of the project.