A light and friendly Cloudflare DDNS client written by pure C with libcurl

• Use a single file to configure and cache, while saving the original indents and comments
• Support multiple accounts, domains, records and unlimited types (not limited to A, AAAA)
• Get new values from url and automatically update the corresponding DNS record

# comment
ipv4? ipv4.example.com
ipv4? ipv4.icanhazip.com
ipv6? ipv6.icanhazip.com # comment
text? https://example.com/text

[email protected]: 59253b9655ed2b92d1563a2b960a8025b1ca1
  example1.com/
    A    @   ipv4 # comment
    AAAA www ipv4

[email protected]: e23a6d4ddb46f4f9fc8cf033f064a42217388
  example2.com/ d39383d73f510f79e82788232719fc49
    AAAA dav ipv6
    TXT  @   text bad_recoird_id

Each line is executed sequentially as a separate statement. Effect statements can be like this:

• var? url [content]

Get value from the url , update content and bind to the variable var. Cannot be rebinded.

• email: apikey

Set email and apikey, must provide apikey otherwise email will be earsed too.

• zone_name/ [zone_id]

Set zone_name . The zone_id will be cached after this. Do not check if zone_id is valid.

• type name var [record_id][!]

If var changed, update this record. If update failed and the record_id is privided by the file, try to regain the id then try again. If failed again, a ! will be appended to indicate force update next time.

$ cfddns cfddns.conf
ipv4? ipv4.example.com #request_failed
ipv4? ipv4.icanhazip.com 153.68.35.233 #changed
ipv6? ipv6.icanhazip.com # comment  #request_failed
text? https://example.com/text value #changed

[email protected]: 
  example1.com/  #got_zone_id
    A    @   ipv4 # comment #updated
    AAAA www ipv4 ! #update_failed 

[email protected]: 
  example2.com/ 
    AAAA dav ipv6  #var_undefined 
    TXT  @   text  #updated

The output is from the original config file and is almost same with the content write back to the config file, except no secrets like apikey in output and no prompt like #changed in config file.

• libcurl

$ make
$ sudo make install

• /usr/local/bin/cfddns
• /etc/cfddns.conf (no override)

$ make
$ sudo make install-systemd

• /usr/local/bin/cfddns

• /etc/cfddns.conf (no override)

• /etc/systemd/system/cfddns.service

  run journalctl -u cfddns to check the logs

• /etc/systemd/system/cfddns.timer

  edit OnUnitActiveSec= line then run systemd daemon-reload to change the interval

MIT © Chinory