Links are almost always base64 encoded now and the online url decoders always produce garbage. I was wondering if there is a project out there that would allow me to self-host this type of tool?
I’d probably network this container through gluetun because, yanno, privacy.
Edit to add: Doesn’t have to be specifically base64 focused. Any link decoder that I can use in a privacy respecting way, would be welcome.
Edit 2: See if your solution will decode this link (the one in the image): https://link.sfchronicle.com/external/41488169.38548/aHR0cHM6Ly93d3cuaG90ZG9nYmlsbHMuY29tL2hhbWJ1cmdlci1tb2xkcy9idXJnZXItZG9nLW1vbGQ_c2lkPTY4MTNkMTljYzM0ZWJjZTE4NDA1ZGVjYSZzcz1QJnN0X3JpZD1udWxsJnV0bV9zb3VyY2U9bmV3c2xldHRlciZ1dG1fbWVkaXVtPWVtYWlsJnV0bV90ZXJtPWJyaWVmaW5nJnV0bV9jYW1wYWlnbj1zZmNfYml0ZWN1cmlvdXM/6813d19cc34ebce18405decaB7ef84e41 (it should decode to this page: https://www.hotdogbills.com/hamburger-molds)
There’s
base64 -d
on the command line.base64 -d
Right but the
/
in the url trips it up and I’d like to just copy/paste the full url and have it spit out the proper, decoded link.The
/
character isn’t a part of the base64 encoding. In fact, only one part of the URL looks like base64. No plain base64 tool (whether via CLI, self-hosted, or otherwise) will be able to decode an entire URL like that. You’ll first need to parse the URL to isolate the base64 part. This is literally solved with a single line of bash:echo "https://link.sfchronicle.com/external/41488169.38548/aHR0cHM6Ly93d3cuaG90ZG9nYmlsbHMuY29tL2hhbWJ1cmdlci1tb2xkcy9idXJnZXItZG9nLW1vbGQ_c2lkPTY4MTNkMTljYzM0ZWJjZTE4NDA1ZGVjYSZzcz1QJnN0X3JpZD1udWxsJnV0bV9zb3VyY2U9bmV3c2xldHRlciZ1dG1fbWVkaXVtPWVtYWlsJnV0bV90ZXJtPWJyaWVmaW5nJnV0bV9jYW1wYWlnbj1zZmNfYml0ZWN1cmlvdXM/6813d19cc34ebce18405decaB7ef84e41" | cut -d/ -f6 | base64 -d
See TIO for example.
edit: add TIO link
- Thank you for this
- You know more than I do re: bash. Where can I learn what
| cut -d/ -f6 |
means? I assume thecut
is the parsing? But maybe that is wrong? Would love to learn how to learn this.
Cut into fields based on the delimiter (/ in this case). The “-f6” selects which field you want.
Well, the URL is a bit weird.echo "aHR0cHM6Ly93d3cuaG90ZG9nYmlsbHMuY29tL2hhbWJ1cmdlci1tb2xkcy9idXJnZXItZG9nLW1vbGQ" | base64 -d
gives me “https://www.hotdogbills.com/hamburger-molds/burger-dog-mold”. (Without the ‘s’.) And then there are about 176 characters left. I suppose the underscore is some delimiter. The rest is:
echo "c2lkPTY4MTNkMTljYzM0ZWJjZTE4NDA1ZGVjYSZzcz1QJnN0X3JpZD1udWxsJnV0bV9zb3VyY2U9bmV3c2xldHRlciZ1dG1fbWVkaXVtPWVtYWlsJnV0bV90ZXJtPWJyaWVmaW5nJnV0bV9jYW1wYWlnbj1zZmNfYml0ZWN1cmlvdXM" | base64 -d
“sid=6813d19cc34ebce18405deca&ss=P&st_rid=null&utm_source=newsletter&utm_medium=email&utm_term=briefing&utm_campaign=sfc_bitecurious”
And I suppose the stuff after the last slash is there for some other reason, tracking or some hash or whatever. But the things before that are the URL and the parameters.
But the question remains whether we have some kind of tool to do this automatically and make it a bit easier…
I really appreciate all of the time and effort you spent on this url. You’re right, the url is weird, which is why I thought it was a good example.
But the question remains whether we have some kind of tool to do this automatically and make it a bit easier…
But you nailed it with this last sentence. Especially when one is on mobile.
Thanks for replying again.
I know. Guess I mainly wanted to say your given solution isn’t the entire story and the potential tool should decode the parameters as well, they might or might not be important. I’m often at the computer and I regularly do one-off tasks this way… But I’m aware it might not be an one-off task to you and you might not have a Linux terminal open 24/7 either 😉 Hope some of the other people have what you need. And btw… since I clicked on a few of the suggestions: I think URL encoding is a different thing, that’s with all the percent signs and not base64 like here.
Just put it in quotes?
This is the internet, maybe build it yourself instead of demanding others do the work for you?
You could also just as easily only paste in the encoded part and put the decoded bit back into the link yourself.
No one is demanding anything. I’m simply stating my preferred solution, which would work on both mobile and desktop, and asking if anyone knows if that solution or something similar already exists.
Nothing suggested so far will properly decode the link that I’ve included above.
But there is no reason to build something duplicative if a solution is already out there. Hence, the post.
you strike me as a competent developer but you lack the experience with Linux.
install xclip, then copy your URL and use the following command.
base64 -d "$(xclip -o)"
there’s probably a better way but I’m just remembering off the top of my head.
could probably pipe it into something that would spit it out with each param on new lines but you’ll need to google that.
There’s something else going on there besides base64 encoding of the URL – possibly they have some binary tracking data or other crap that only makes sense to the creator of the link.
It’s not hard to write a small Python script that gets what you want out of a URL like that though. Here’s one that works with your sample link:
#!/usr/bin/env python3 import base64 import binascii import itertools import string import sys input_url = sys.argv[1] parts = input_url.split("/") for chunk in itertools.accumulate(reversed(parts), lambda b,a: "/".join([a,b])): try: text = base64.b64decode(chunk).decode("ascii", errors="ignore") clean = "".join(itertools.takewhile(lambda x: x in string.printable, text)) print(clean) except binascii.Error: continue
Save that to a file like
decode.py
and then you can you run it on the command line likepython3 ./decode.py 'YOUR-LINK-HERE'
e.g.
$ python3 ./decode.py 'https://link.sfchronicle.com/external/41488169.38548/aHR0cHM6Ly93d3cuaG90ZG9nYmlsbHMuY29tL2hhbWJ1cmdlci1tb2xkcy9idXJnZXItZG9nLW1vbGQ_c2lkPTY4MTNkMTljYzM0ZWJjZTE4NDA1ZGVjYSZzcz1QJnN0X3JpZD1udWxsJnV0bV9zb3VyY2U9bmV3c2xldHRlciZ1dG1fbWVkaXVtPWVtYWlsJnV0bV90ZXJtPWJyaWVmaW5nJnV0bV9jYW1wYWlnbj1zZmNfYml0ZWN1cmlvdXM/6813d19cc34ebce18405decaB7ef84e41' https://www.hotdogbills.com/hamburger-molds/burger-dog-mold
This script works by spitting the URL at ‘/’ characters and then recombining the parts (right-to-left) and checking if that chunk of text can be base64 decoded successfully. If it does, it then takes any printable ASCII characters at the start of the string and outputs it (to clean up the garbage characters at the end). If there’s more than one possible valid interpretation as base64 it will print them all as it finds them.
Wow, this is really helpful. Thank you!!
Cyberchef!
Cyberchef does this and so so much more https://github.com/gchq/CyberChef
IT-Tools is kind of fun: a web page full of common tools, converters, references, cheat sheets, etc.
https://addons.mozilla.org/en-US/firefox/addon/redirect-bypasser-webextension/ in desktop Firefox seems to work for your link. For mobile there might be apps that you share the link to and they dissect it, but a very quick search didn’t turn up anything.
That url isn’t base64 encoded. You can tell by the fact that it’s still a URL……
Use a bash command line:
https://stackoverflow.com/questions/6250698/how-to-decode-url-encoded-string-in-shell
CorentinTh/it-tools does that and a lot more