r53-ddns

Brief

this was intended to solve the problem of when your local ISP force renews your PublicIP and no one can reach your not-sure-if-toaster-or-minecraft-server.

what it ended up as, was instead a mockery of dynamic dns, progam/scripting, error handling, all in memory-safe rust. whatever that means, right?

"this is the worst example of working code ive ever seen" // "ah, but you have seen the code working"

-- Rskntroot 2024

Assumptions

Your ISP randomly changes your PublicIP and that pisses you off.
You have no idea how DDNS is actually supposed to work.
- dns is all smoke and mirrors, confirmed.
You just want something that will curl ipv4.icanhazip.com and push the update to Route53.
You plan on handjamming this into a cron job on your webserver/loadbalancer.
...
Profit.

Congratulations, this is the package for you.

Setup

use output of below command to create the IAM policy

zone_id=<zone_id> envsubst < AllowRoute53RecordUpdate.policy

create IAM user, generate access keys for automated service
log into aws with the acct on the machine where you install this binary
```
aws sso login --profile
```
setup a user-level cron job to poll at your leisure
```
0 * * * * ~/home/lost/.r53-update-dns.sh
```

Usage

$ r53-ddns -h
A CLI tool for correcting drift between your PublicIP and Route53 DNS A RECORD

Usage: r53-ddns --zone-id <ZONE_ID> --domain-name <DOMAIN_NAME>

Options:
  -z, --zone-id <ZONE_ID>          DNS ZONE ID  (see AWS Console Route53)
  -d, --domain-name <DOMAIN_NAME>  DOMAIN NAME  (ex. 'docs.rskio.com.')
  -h, --help                       Print help

Drift Detected

$ r53-ddns -z ${aws_dns_zone_id} -d smp.rskio.com.

The dynamic IP provided by the ISP has drifted. 10.0.11.201 -> 10.0.88.219
Requested DNS record update to PublicIP: 10.0.88.219
Change ID: /change/C04224022UE1ZQA26RE7O, Status: Pending
Change ID: /change/C04224022UE1ZQA26RE7O, Status: Insync
The change request has been completed.

No Drift Detected

$ r53-ddns -z  ${aws_dns_zone_id} -d example.com.

The DNS record is currently up to date with the public IP: 10.0.88.219

Tests

Yeah, I have em! Well... one of them.

$ cargo test
   Compiling r53-ddns v0.1.0 (~/workspace/r53-ddns)
    Finished `test` profile [unoptimized + debuginfo] target(s) in 3.81s
     Running unittests src/main.rs (target/debug/deps/r53_ddns-9ff92b89721daeea)

running 1 test
test tests::get_public_ip_works ... ok

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.07s

Q&A

Why are you doing AWS calls instead of us nslookup and compare that?

Why in the world would internal DNS give me a PublicIP? Imagine not implementing internal DNS.

Why did you do create this monster?

To prove to myself that with the help of LLMs that even I could go from nothing to a deployed tokio async rust binary in less than 8 hours. And thats exactly what I did.

wen IPv6?

Stfu, John. How about, wen PR?

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