ACME is not working with IPv6 in SAN

[M0NsTeRRR]

Describe the bug
The HTTP-01 & challenge does not format properly domain when it's set to the IPv6 address must be enclosed in brackets.
https://github.com/hashicorp/vault/blob/main/builtin/logical/pki/acme_challenges.go#L126

Challenge fail with this error in lego

[INFO] [2a0c:b641:2c0:110::21] acme: Trying to solve HTTP-01\n2024/09/23 22:06:14 [INFO] Skipping deactivating of valid auth: https://vault.unicornafk.fr:8200/v1/pki/acme/authorization/2784580b-b852-4fce-8ed3-3ab805c816f9\n2024/09/23 22:06:14 [INFO] Skipping deactivating of valid auth: https://vault.unicornafk.fr:8200/v1/pki/acme/authorization/55e91f06-fb6e-aec0-e303-7769a202817a\n2024/09/23 22:06:14 [INFO] Deactivating auth: https://vault.unicornafk.fr:8200/v1/pki/acme/authorization/7c59f2a2-b0bf-7e70-0d77-e5a50af70a8c\n2024/09/23 22:06:14 [INFO] Unable to deactivate the authorization: https://vault.unicornafk.fr:8200/v1/pki/acme/authorization/7c59f2a2-b0bf-7e70-0d77-e5a50af70a8c\n2024/09/23 22:06:14 Could not obtain certificates:\n\terror: one or more domains had a problem:\n[2a0c:b641:2c0:110::21] acme: error: 400 :: urn:ietf:params:acme:error:incorrectResponse :: Response received didn\'t match the challenge\'s requirements: error validating http-01 challenge 7c59f2a2-b0bf-7e70-0d77-e5a50af70a8c-http-01: http-01: failed to fetch path http://2a0c:b641:2c0:110::21/.well-known/acme-challenge/JJqdDgTEKYUUksBUhT9hWeo9eVkM: Get "http://2a0c:b641:2c0:110::21/.well-known/acme-challenge/JJqdDgTEKYUUksBUhT9hWeo9eVkM": dial tcp: lookup 2a0c:b641:2c0:110:: no such host; this may occur if the validation target was misconfigured: check that challenge responses are available at the required locations and retry.\n

To Reproduce
Steps to reproduce the behavior:

1. Configure pki with ACME
2. Try to get a certificate through vault ACME with lego (for example) with an IPv6 in the SAN.

Expected behavior
Vault should connect properly to my IPv6 webserver

Environment:

• Vault Server Version (retrieve with vault status): 1.17.5
• Vault CLI Version (retrieve with vault version):
• Server Operating System/Architecture: Ubuntu 22.04 Server LTS

[stevendpclark]

Hi @M0NsTeRRR, thanks for reporting the issue!

PR #28718, should address the issue and be included in the next round of Vault releases.

[M0NsTeRRR]

Thanks you very much for the fix @stevendpclark :)