Does the signed url cache on Google Cloud Storage? - google-cloud-storage

https://cloud.google.com/storage/docs/access-control/signed-urls
I want to use a signed url.
If I use this url structure, can I also use the cache system?
I want to avoid spending too much traffic from the same files.

In my opinion this is not possible. According to this document cache-control applies to "publicatly accessible" objects. Which if I understand correctly means that they have to be allowed to allUsers.
On the other side accoriding to Signed URL documentation:
When you generate a signed URL, you specify a user or service account
which must have sufficient permission to make the request that the
signed URL will make
As I understand this means that it's not allowed to allUsers and you cannot use cache.
I hope this theoretical thinking will help you somehow :)

Related

Cloud Storage - Disabled Public Access Prevention, but Failed

Okay, I was using Flutter and Firebase to upload data into Cloud Storage. I gained the downloadURL which can be accessible on web if people know the URL. I had enabled Public Access Prevention in Google Cloud Storage Console based on this doc and chose Access Control Uniform for this on doc.
I also had added Security Rule in Firebase Cloud Storage, so only Users with certain custom token can use it. But, it seems useless as everyone can get its downloaded URL. My question is why is that I still able to access the file if I am using the same URL which was I stored in Firestore? You can test it on this url.
Can hacker get the download URL I downloaded from Firestore?
Is there a secure way to download song from Firebase Cloud Storage so hacker won't get its URL?
Thank you for helping me out.
Updated v2:
I just found out that current audio file has its own AuthenticatedUrl as shown on this picture below. How can I get access to this url?
Updated v1:
I think I haven't activated Firebase App Check. Does this feature have ability to prevent it from being accessed publicly or maybe there is other things that I have to do to be able to prevent it being accessed publicly, beside all ways I described above???
Security rules only check if a user can get the download URL and do not restrict anyone from using it. You can use the getData() method instead. It doesn't return any URL and downloads the files directly and is controlled by security rules. So a user must be authenticated to fetch them.
As mentioned in the Answer :
If you're using the FlutterFire Storage library in your app, you can
call getData on a reference to the file to get its data. So with
that you just need to know the path to the data, and you won't need
the download URL in your application. Once you have the data locally,
you can create an image out of it with: Converting a byte array to
image in Flutter?
Unlike download URLs, the call to getData() is
checked by security rules, so you'll have to ensure that the user is
permitted to access the file.
You can also refer to this Answer :
For web apps: in the JavaScript/Web SDK using a download URL is the
only way to get at the data, while for the native mobile SDKs we also
have getData() and getFile() methods, which are enforced through
security rules.
Until that time, if signed URLs fit your needs
better, you can use those. Both signed URLs and download URLs are just
URLs that provide read-only access to the data. Signed URLs just
expire, while download URLs don't.
For more information, you can refer to this Github issue where a similar issue has been discussed.

Node - request authentication using secret

Lets assume i have REST api with products and i want it to be accessible only for specified users.
The list of users is known for me and i'm looking for some way to give them safe access to my API.
I don't want to create authentication with username and password, generate token and this stuff.
What i can imagine is that i'm giving each of my users some secret string
and they use it in every request.
And what i need is some example/tutorial/name of this kind of solution,
i'm sure there are some standards for that but i don't know it.
I know it's kind of nooby question - sorry for that, i'm just asking ;).
Thanks in advance!!
You are looking for a simple shared-secret authentication. A simple solution in this case is just to check for the secret as a param (or it could be in the request header). For example, the client can call:
https://example.com/valuable-stuff?secret=2Hard2Gue$$
You implement this in your web request handler as:
SECRET = '2Hard2Gue$$'
function showValuableStuff() {
if (params['secret'] != SECRET)
return NotFounderError;
// now retrieve and output the resource
}
Some practical considerations are:
Use a secure connection for this to prevent the secret being leaked (ie a secure HTTPS exposure).
Be careful where you store the source code if you're hard-coding it. A fancier solution is use an environment variable which is set on the server, so you keep this out of the source code. Or at least to encrypt the part of the source that contains the secret.
While this is fine for simple solutions, it violates the basic security principle of accountability because you are sharing the secret with multiple people. You might want to consider allocating each individual their own random string, in which case, you may as well use HTTP Basic Authentication as it's well supported by Apache and other web servers, and still quite a lightweight approach.

Google cloud storage authentication confusion

I have a newbie question regarding google cloud storage. I'm looking to create a website where people can upload files (similar to Flickr in concept) and view them. I was looking at google's cloud storage option and it seemed interesting. I got a little hung up on the authentication process. Do all users need a Google account or did I just misread it? I guess my question is can I create a site where everyone doesn't have to sign up for a google account?
Thank you for your patience and help
Nope, there's no need for customers to have their own Google accounts. Google Cloud Storage supports that, in case you want to say "these accounts have access to this data", but you can also let your app grant access on a per-request basis using whatever logic or authentication scheme you like.
This is usually accomplished with signed URLs. Basically, you'd use your credentials to sign a very specific request (download object X, upload an object with name Y) and pass that URL to the user for them to use. Signed URLs are only valid for as long as you like (one of the parameters is how long the URL is good for).
Documentation on signed URLs are here: https://developers.google.com/storage/docs/accesscontrol#Signed-URLs
It's not strictly necessary to require a user to be logged in in order to write to your bucket (e.g., we have a public-read-write canned ACL for buckets), but it's generally a bad idea. Any data stored in your bucket will ultimately be charged to you, so allowing anyone to write without authentication opens you up to a great deal of abuse.
Likewise, you could make all of your objects public-read, but then you get charged for the bandwidth costs and have no control over it (though this is a much more reasonable thing to do than public-write).
A safer option would be to proxy bytes for your users - i.e., only you/your app can write to your bucket, and your users hand their bytes to you.
Generally speaking, though, the only types of authentication we support are Google accounts, signed URLs, and anonymous users.

How do you get or generate a URL to the object in a bucket?

I'm storing objects in buckets on google cloud storage. I would like to provide a http url to the object for download. Is there a standard convention or way to expose files stored in cloud storage as http urls?
Yes. Assuming that the objects are publicly accessible:
http://BUCKET_NAME.storage.googleapis.com/OBJECT_NAME
You can also use:
http://storage.googleapis.com/BUCKET_NAME/OBJECT_NAME
Both HTTP and HTTPS work fine. Note that the object must be readable by anonymous users, or else the download will fail. More documentation is available at https://developers.google.com/storage/docs/reference-uris
If it is the case that the objects are NOT publicly accessible and you only want the one user to be able to access them, you can generate a signed URL that will allow only the holder of the URL to download the object, and even then only for a limited period of time. I recommend using one of the GCS client libraries for this, as it's easy to get the signing code slightly wrong: https://developers.google.com/storage/docs/accesscontrol#Signed-URLs
One way is to use https://storage.cloud.google.com// see more documentation at
https://developers.google.com/storage/docs/collaboration#browser
If the file is not public, you can use this link to the file and it will authenticate with your signed in Google account:
https://storage.cloud.google.com/{bucket-name}/{folder/filename}
Otherwise generate a signed URL:
gsutil signurl -d 10m Desktop/private-key.json gs://example-bucket/cat.jpeg

What is the best way to secure a RESTful API to be accessed on an iPhone

I am looking for some suggestions on how to secure access to a RESTful API which initially be used by an iPhone application, but will have other clients in the future. The data exposed by this API must be kept secure as it may contain health information. All access will be done over HTTPS.
I was thinking that I'd like to require pre-registration of the iphones at setup and then also some type of PIN/Password on each request. So, simply knowing the password without pre-registering the phone/client won't provide access. I was thinking about somehow tying it to the iPhone identifier if that is possible, but not sure it would provide any additional security. The iPhone identifier is just another piece of information and it may not even be that secret.
So, some requirements would be:
Use some type of pin-based solution on the iPhone, but want more security then a simple 4-6 digit pin can provide.
No passwords could be sent in the clear.
Not be subject to reply attacks
Having to pre-exchange some data between client and server when setting up client is OK.
I would think that, if the application contains medical records, you would want to have the user authenticate every time they use the application or, at least, have some way of pushing down a disable message that renders the app useless in the case where it is lost or stolen. The 4-6 character password (pin) would also concern me with respect to HIPAA, if it applies.
You might want to treat it as a standard web app from the server perspective and do session-based authentication and access with a session that times out, perhaps after a long period, and re-authentication on timeout.
You could use SSL with client authentication. If a device gets lost, you can remove the certificate on the server. There are some obstacles though:
It is not entirely clear if/how you can do client authenticated SSL on the iPhone Unfortunately, there is not much documentation about it. Have a look at Certificate, Key, and Trust Services Reference
You have to create a private key for every device
You also have to figure out a secure way to transfer the private key to the device