Add `ctfcloud.net` domain

[mgoudy91]

Public Suffix List (PSL) Pull Request (PR) Template

Each PSL PR needs to have a description, rationale, indication of DNS validation and syntax checking, as well as a number of acknowledgements from the submitter. This template must be included with each PR, and the submitting party MUST provide responses to all of the elements in order to be considered.

Checklist of required steps

• [x] Description of Organization

• [x] Robust Reason for PSL Inclusion

• [x] DNS verification via dig

• [x] Run Syntax Checker (make test)

• [x] Each domain listed in the PRIVATE section has and shall maintain at least two years remaining on registration, and we shall keep the _PSL txt record in place in the respective zone(s) in the affected section

Submitter affirms the following:

• [x] We are listing any third-party limits that we seek to work around in our rationale such as those between IOS 14.5+ and Facebook (see Issue #1245 as a well-documented example)
  • Cloudflare
  • Letsencrypt
  • <UPDATE THIS LIST WITH YOUR LIMITATIONS! REMOVE ENTRIES WHICH DO NOT APPLY! REMOVE THIS LINE!>

• [x] This request was not submitted with the objective of working around other third-party limits

• [x] The submitter acknowledges that it is their responsibility to maintain the domains within their section. This includes removing names which are no longer used, retaining the _psl DNS entry, responding to e-mails to the supplied address. Failure to maintain entries may result in removal of individual entries or the entire section.

• [x] The Guidelines were carefully read and understood, and this request conforms
• [x] The submission follows the guidelines on formatting and sorting

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For Private section requests that are submitting entries for domains that match their organization website's primary domain, please understand that this can have impacts that may not match the desired outcome and take a long time to rollback, if at all.

To ensure that requested changes are entirely intentional, make sure that you read the affectation and propagation expectations, that you understand them, and confirm this understanding.

PR Rollbacks have lower priority, and the volunteers are unable to control when or if browsers or other parties using the PSL will refresh or update.

(Link: about propagation/expectations)

• [x] Yes, I understand. I could break my organization's website cookies etc. and the rollback timing, etc is acceptable. Proceed.

Description of Organization

Organization Website: https://contentful.com/

Reason for PSL Inclusion

Mainly because of cookie security:

• We provide each customer with a unique subdomain of ctfcloud.net.
• We want our customers' apps to be isolated from each other (cookies, etc.)
• We want to prevent setting cookies on the apex domains.

Number of users this request is being made to serve:

18000+ customers.

DNS Verification via dig

Results of Syntax Checker (make test)

[wdhdev]

• [ ] Domain expiry 2y+
• [ ] _psl TXT record
• [x] Sorting

[mgoudy91]

Sorry for having you review this before we had everything in place @wdhdev. Hopefully everything looks good now that we've had a chance to update our infrastructure:

Let me / us know if there's anything else you'd need us to do for this, and thanks again for the review!

[groundcat]

• [x] Expiration (Note: Must STAY >2y at all times)
  • [x] ctfcloud.net expires 2028-03-02
• [x] DNS _psl entries (Note: Must STAY in place)
  • "https://github.com/publicsuffix/list/pull/2073"
• [x] Tests pass
• [x] Sorting
• [x] Reasoning/Organization description
  • a number of subdomains discovered
  • use of ctfcloud\.net found on a partner website
• [x] Non-personal email address