Encoding Login information in your image (safely)

Tim Mackinnon wrote

Hi - I’m struggling to find something that I saw that discussed this issue kind of.

In my image (its actually a headless one - but this could apply to a fat image too) - I build an application that needs access to a  service (in this case an S3 bucket).

The AWS library I’m using (but others are similar) has an AWSLogin class singleton where I can specify a username and password. So in a playground I can do that and test it all works etc.

However, for deployment its never a good idea to encode this info into your code (particularly if you use Iceberg and GitHub) - SO, I am using secret variable support in GitLab - which I’ve seen many projects do in other languages. This way, I type in those details into an encrypted place in the CI and it then exposes them as temporary variables when I build my system (so far so good).

Now in my build - I run a little script like this and pass on those variables (neatly, Gitlab doesn’t show their values in its logs):

./pharo Pharo.image --no-default-preferences --save --quit st config.st \
    "{‘$USER'. ‘$PWD'}"

In config.st I then extract these command line parameters (the ST handler nicely exposes the extra parameter array so I didn’t have to do anything custom)

"Expect image to be called with params as a last arg array"
config := Array readFrom: Smalltalk arguments last.
user := config at: 1.
pwd := config at: 2.

DBConfig default
   accessKey: user;
   pKey: pwd;
   yourself.
So it all looks pretty good so far - however it occurs to me that if you get hold of a .image and were to browse all of the Strings - e.g.
./pharo Pharo.image eval "(ByteString allInstances)”
I think you would ulimtately find those strings unless the Class encrypts them in some way right?
So I’m wondering why we don’t have an EncryptedString object for just this (I’ve seen lots of cryptography libraries etc), but isn’t this quite a common thing to deal with? And should Pharo provide something that library writers adopt to encourage better image safety? Or am I wrong in my analysis?

Tim

I do a lot of deployments on AWS elastic beanstalks.

I put the credentials into environment variables on the beanstalk.

When running locally, the credentials are in the environment on my machine.

On Aug 16, 2017, at 9:55 AM, Tim Mackinnon <[hidden email]> wrote:

Hi - I’m struggling to find something that I saw that discussed this issue kind of.

In my image (its actually a headless one - but this could apply to a fat image too) - I build an application that needs access to a  service (in this case an S3 bucket).

The AWS library I’m using (but others are similar) has an AWSLogin class singleton where I can specify a username and password. So in a playground I can do that and test it all works etc.

However, for deployment its never a good idea to encode this info into your code (particularly if you use Iceberg and GitHub) - SO, I am using secret variable support in GitLab - which I’ve seen many projects do in other languages. This way, I type in those details into an encrypted place in the CI and it then exposes them as temporary variables when I build my system (so far so good).

Now in my build - I run a little script like this and pass on those variables (neatly, Gitlab doesn’t show their values in its logs):

./pharo Pharo.image --no-default-preferences --save --quit st config.st \
    "{‘$USER'. ‘$PWD'}"

In config.st I then extract these command line parameters (the ST handler nicely exposes the extra parameter array so I didn’t have to do anything custom)

"Expect image to be called with params as a last arg array"
config := Array readFrom: Smalltalk arguments last.
user := config at: 1.
pwd := config at: 2.

DBConfig default
   accessKey: user;
   pKey: pwd;
   yourself.

So it all looks pretty good so far - however it occurs to me that if you get hold of a .image and were to browse all of the Strings - e.g.

./pharo Pharo.image eval "(ByteString allInstances)”

I think you would ulimtately find those strings unless the Class encrypts them in some way right?

So I’m wondering why we don’t have an EncryptedString object for just this (I’ve seen lots of cryptography libraries etc), but isn’t this quite a common thing to deal with? And should Pharo provide something that library writers adopt to encourage better image safety? Or am I wrong in my analysis?

Tim