policies: let terraform-git seed the gitea engine admin credential to KV (#102)

## Why

terraform-git now provisions the `gitea-vault-admin` site-admin bot and writes its generated password to `kv/service/vault/au/syd1/secret_backend/gitea/config` (as `admin_username` + `admin_password`) so the gitea secrets engine can consume it at creation time. The `woodpecker_terraform_git` / `terraform_git` identity has no write access to that KV path, so its apply would 403 without this grant.

The deployer that *reads* the seed already has read access via `policies/kv/service/vault/secret_backends_read.yaml` (`kv/data/service/vault/+/+/secret_backend/*`), so only the write side is added here.

## Change

- Add `policies/kv/service/vault/au/syd1/secret_backend/gitea/config_write.yaml` granting `create`/`read`/`update` on the gitea config KV path to the `terraform_git` approle and `woodpecker_terraform_git` k8s role.

## Ordering

Merge + apply this before the terraform-git `benvin/gitea-vault-admin` PR applies (which performs the write). Files are disjoint from the other gitea terraform-vault PRs (#100, #101).

https://claude.ai/code/session_015ur3i7D2azsMAWTSVABApv
Reviewed-on: #102
Co-authored-by: Ben Vincent <ben@unkin.net>
Co-committed-by: Ben Vincent <ben@unkin.net>

config/config.hcl

@@ -239,18 +239,5 @@ locals {
       })
       if startswith(file_path, "rancher_secret_backend_role/")
     }
-    gitea_secret_backend = {
-      for file_path, content in local.all_configs :
-      trimsuffix(basename(file_path), ".yaml") => content
-      if startswith(file_path, "gitea_secret_backend/")
-    }
-    gitea_secret_backend_role = {
-      for file_path, content in local.all_configs :
-      trimsuffix(replace(file_path, "gitea_secret_backend_role/", ""), ".yaml") => merge(content, {
-        name    = trimsuffix(basename(file_path), ".yaml")
-        backend = dirname(replace(file_path, "gitea_secret_backend_role/", ""))
-      })
-      if startswith(file_path, "gitea_secret_backend_role/")
-    }
   }
 }

config/gitea_secret_backend/gitea.yaml

@@ -1,11 +0,0 @@
-# Mounts the gitea token secrets engine at "gitea" and writes its config.
-# The seeded site-admin credentials are sensitive and read from KV, not stored
-# here:
-#   kv/service/vault/au/syd1/secret_backend/gitea/config
-#   -> keys: admin_username (required), admin_password (required)
-# Populate that KV path with a purpose-built Gitea site-admin bot (2FA disabled)
-# BEFORE applying, then run `vault write -f gitea/config/rotate-root` after the
-# first apply so only Vault holds the admin password.
-description: "Gitea ephemeral scoped access token engine"
-gitea_url: "https://git.unkin.net"
-request_timeout_seconds: 30

config/gitea_secret_backend_role/gitea/teabot-implementer.yaml

@@ -1,14 +0,0 @@
-# Role minting ephemeral tokens for the teabot-implementer bot user.
-# The implementer clones/pushes code and opens pull requests, so it gets write
-# on repositories (clone + push + PR create) and write on issues (PR/issue
-# comments). Read is implied by write. No admin/org/user-write scopes.
-# Reading gitea/creds/teabot-implementer mints a lease-bound token deleted from
-# Gitea on revoke/expiry.
----
-username: teabot-implementer
-scopes:
-  - write:repository
-  - write:issue
-token_name_prefix: vault-teabot-implementer
-ttl: 3600      # 1h
-max_ttl: 14400 # 4h

config/gitea_secret_backend_role/gitea/teabot-reviewer.yaml

@@ -1,14 +0,0 @@
-# Role minting ephemeral tokens for the teabot-reviewer bot user.
-# The reviewer reads code and posts pull-request reviews/comments, so it gets
-# read on repositories (fetch diffs) and write on issues (PR reviews + issue/PR
-# comments). No repository-write, admin, org, or user scopes.
-# Reading gitea/creds/teabot-reviewer mints a lease-bound token deleted from
-# Gitea on revoke/expiry.
----
-username: teabot-reviewer
-scopes:
-  - read:repository
-  - write:issue
-token_name_prefix: vault-teabot-reviewer
-ttl: 3600      # 1h
-max_ttl: 14400 # 4h

config/plugins/vault-plugin-secrets-gitea.yaml

@@ -1,11 +0,0 @@
-# config/plugins/vault-plugin-secrets-gitea.yaml
-# Imports (registers) the gitea secrets plugin in the catalog. Filename =
-# catalog name = mount type. The binary is installed on the OpenBao nodes by
-# Puppet (openbao-plugin-secrets-gitea RPM ->
-# /opt/openbao-plugins/vault-plugin-secrets-gitea).
-#
-# sha256 pins the released v0.1.0 binary; bump it in lockstep with any RPM
-# upgrade or OpenBao will refuse to launch the plugin.
-type: secret
-command: vault-plugin-secrets-gitea
-sha256: "8f67fbc216effada5fd7399888a710b62fad83be0b31761a439e7dec3d56509b"

environments/au/syd1/terragrunt.hcl

@@ -78,9 +78,6 @@ inputs = {
   rancher_secret_backend_service_account = local.config.rancher_secret_backend_service_account
   rancher_secret_backend_role            = local.config.rancher_secret_backend_role
 
-  gitea_secret_backend      = local.config.gitea_secret_backend
-  gitea_secret_backend_role = local.config.gitea_secret_backend_role
-
   # Pass policy maps to vault_cluster module
   policy_auth_map  = local.policies.policy_auth_map
   policy_rules_map = local.policies.policy_rules_map

modules/vault_cluster/main.tf

@@ -421,40 +421,6 @@ module "rancher_secret_backend_role" {
   depends_on = [module.rancher_secret_backend_service_account]
 }
 
-module "gitea_secret_backend" {
-  source = "./modules/gitea_secret_backend"
-
-  for_each = var.gitea_secret_backend
-
-  path                    = each.key
-  plugin                  = each.value.plugin
-  description             = each.value.description
-  gitea_url               = each.value.gitea_url
-  country                 = var.country
-  region                  = var.region
-  ca_cert                 = each.value.ca_cert
-  tls_skip_verify         = each.value.tls_skip_verify
-  request_timeout_seconds = each.value.request_timeout_seconds
-
-  depends_on = [module.plugin]
-}
-
-module "gitea_secret_backend_role" {
-  source = "./modules/gitea_secret_backend_role"
-
-  for_each = var.gitea_secret_backend_role
-
-  backend           = each.value.backend
-  name              = each.value.name
-  username          = each.value.username
-  scopes            = each.value.scopes
-  token_name_prefix = each.value.token_name_prefix
-  ttl               = each.value.ttl
-  max_ttl           = each.value.max_ttl
-
-  depends_on = [module.gitea_secret_backend]
-}
-
 module "vault_policy" {
   source = "./modules/vault_policy"
 

modules/vault_cluster/modules/gitea_secret_backend/main.tf

@@ -1,34 +0,0 @@
-# Mounts the gitea secrets engine and writes its connection config via the
-# giteavaultsecret provider. The plugin is registered ("imported") in the
-# catalog separately (config/plugins/vault-plugin-secrets-gitea.yaml). The
-# seeded site-admin credentials are sensitive and read from KV, not stored in
-# git:
-#   kv/service/vault/<country>/<region>/secret_backend/<path>/config
-# Expected keys: admin_username (required), admin_password (required).
-data "vault_kv_secret_v2" "config" {
-  mount = "kv"
-  name  = "service/vault/${var.country}/${var.region}/secret_backend/${var.path}/config"
-}
-
-resource "gitea_secret_backend" "this" {
-  path                    = var.path
-  plugin                  = var.plugin
-  description             = var.description
-  gitea_url               = var.gitea_url
-  admin_username          = data.vault_kv_secret_v2.config.data["admin_username"]
-  admin_password          = data.vault_kv_secret_v2.config.data["admin_password"]
-  ca_cert                 = var.ca_cert
-  tls_skip_verify         = var.tls_skip_verify
-  request_timeout_seconds = var.request_timeout_seconds
-
-  lifecycle {
-    # The KV seed is a bootstrap credential: it is consumed only when the engine
-    # config is first created. After creation the live admin password is rotated
-    # in place (vault write -f gitea/config/rotate-root) and diverges from the
-    # seed, so re-reading the (possibly stale) KV value must never push it back.
-    # Ignoring the credential attributes makes this module create-only for them.
-    # (The sibling rancher/litellm seed modules do not yet do this and would
-    # re-push their seed on a subsequent apply.)
-    ignore_changes = [admin_username, admin_password]
-  }
-}

modules/vault_cluster/modules/gitea_secret_backend/terraform.tf

@@ -1,13 +0,0 @@
-terraform {
-  required_version = ">= 1.10"
-  required_providers {
-    vault = {
-      source  = "hashicorp/vault"
-      version = "5.6.0"
-    }
-    gitea = {
-      source  = "artifactapi.k8s.syd1.au.unkin.net/terraform-unkin/giteavaultsecret"
-      version = "0.1.0"
-    }
-  }
-}

modules/vault_cluster/modules/gitea_secret_backend/variables.tf

@@ -1,49 +0,0 @@
-variable "path" {
-  description = "Mount path of the gitea secrets engine (e.g. \"gitea\")"
-  type        = string
-}
-
-variable "plugin" {
-  description = "Registered plugin name to mount (the catalog name = mount type)"
-  type        = string
-  default     = "vault-plugin-secrets-gitea"
-}
-
-variable "description" {
-  description = "Human-friendly description of the mount"
-  type        = string
-  default     = null
-}
-
-variable "gitea_url" {
-  description = "Base URL of the Gitea server (e.g. https://git.unkin.net)"
-  type        = string
-}
-
-variable "country" {
-  description = "Country segment of the KV path holding the seeded admin credentials"
-  type        = string
-}
-
-variable "region" {
-  description = "Region segment of the KV path holding the seeded admin credentials"
-  type        = string
-}
-
-variable "ca_cert" {
-  description = "PEM CA certificate that signed the Gitea server's TLS cert (optional; omit to use the system trust store)"
-  type        = string
-  default     = null
-}
-
-variable "tls_skip_verify" {
-  description = "Skip TLS verification of the Gitea server (not recommended)"
-  type        = bool
-  default     = false
-}
-
-variable "request_timeout_seconds" {
-  description = "HTTP timeout in seconds for calls from the plugin to Gitea"
-  type        = number
-  default     = 30
-}

modules/vault_cluster/modules/gitea_secret_backend_role/main.tf

@@ -1,12 +0,0 @@
-# A role that mints short-lived, scoped gitea tokens for a target Gitea user.
-# Reading gitea/creds/<name> produces a lease-bound token that is deleted from
-# Gitea when the lease is revoked or reaches max_ttl.
-resource "gitea_secret_backend_role" "this" {
-  backend           = var.backend
-  name              = var.name
-  username          = var.username
-  scopes            = var.scopes
-  token_name_prefix = var.token_name_prefix
-  ttl               = var.ttl
-  max_ttl           = var.max_ttl
-}

modules/vault_cluster/modules/gitea_secret_backend_role/terraform.tf

@@ -1,9 +0,0 @@
-terraform {
-  required_version = ">= 1.10"
-  required_providers {
-    gitea = {
-      source  = "artifactapi.k8s.syd1.au.unkin.net/terraform-unkin/giteavaultsecret"
-      version = "0.1.0"
-    }
-  }
-}

modules/vault_cluster/modules/gitea_secret_backend_role/variables.tf

@@ -1,37 +0,0 @@
-variable "backend" {
-  description = "Mount path of the gitea secrets engine this role belongs to"
-  type        = string
-}
-
-variable "name" {
-  description = "Role name (read gitea/creds/<name> to mint a token)"
-  type        = string
-}
-
-variable "username" {
-  description = "Target Gitea username the minted tokens belong to"
-  type        = string
-}
-
-variable "scopes" {
-  description = "Gitea access-token scopes granted to minted tokens (write: implies read:)"
-  type        = list(string)
-}
-
-variable "token_name_prefix" {
-  description = "Prefix for the generated Gitea token name (optional)"
-  type        = string
-  default     = null
-}
-
-variable "ttl" {
-  description = "Default lease TTL in seconds for minted tokens"
-  type        = number
-  default     = null
-}
-
-variable "max_ttl" {
-  description = "Maximum lease TTL in seconds for minted tokens"
-  type        = number
-  default     = null
-}

modules/vault_cluster/variables.tf

@@ -388,33 +388,6 @@ variable "rancher_secret_backend_role" {
   default = {}
 }
 
-variable "gitea_secret_backend" {
-  description = "Map of gitea token secret engines to create (mount + config; seeded admin creds read from KV)"
-  type = map(object({
-    plugin                  = optional(string, "vault-plugin-secrets-gitea")
-    description             = optional(string)
-    gitea_url               = string
-    ca_cert                 = optional(string)
-    tls_skip_verify         = optional(bool, false)
-    request_timeout_seconds = optional(number, 30)
-  }))
-  default = {}
-}
-
-variable "gitea_secret_backend_role" {
-  description = "Map of gitea token-minting roles to create"
-  type = map(object({
-    name              = string
-    backend           = string
-    username          = string
-    scopes            = list(string)
-    token_name_prefix = optional(string)
-    ttl               = optional(number)
-    max_ttl           = optional(number)
-  }))
-  default = {}
-}
-
 variable "policy_auth_map" {
   description = "Map of auth mounts -> auth roles -> policy names"
   type        = map(map(list(string)))

policies/gitea/admin.yaml

@@ -0,0 +1,42 @@
+# Allow the vault deployer to manage the gitea token secrets engine: its
+# connection config (seeded admin credentials), in-place root rotation, and
+# token-minting roles.
+#
+# Scoped to gitea/* only, and deliberately excludes gitea/creds/* — minting
+# tokens is for consumers, not the deployer. The plugin-catalog grant needed to
+# import the plugin is the shared, sudo-protected wildcard in
+# policies/sys/plugins/catalog/admin.yaml (already covers this plugin), and
+# mounting the engine uses the deployer's existing sys/mounts/* access, so no
+# new catalog/mount grant is added here (mirrors the rancher engine).
+---
+rules:
+  # Engine connection config (Gitea URL, TLS, seeded admin username/password).
+  - path: "gitea/config"
+    capabilities:
+      - create
+      - read
+      - update
+      - delete
+  # In-place rotation of the seeded admin password (write-only trigger).
+  - path: "gitea/config/rotate-root"
+    capabilities:
+      - create
+      - update
+  # Token-minting roles.
+  - path: "gitea/roles/*"
+    capabilities:
+      - create
+      - read
+      - update
+      - delete
+      - list
+  - path: "gitea/roles"
+    capabilities:
+      - read
+      - list
+
+auth:
+  approle:
+    - tf_vault
+  k8s/au/syd1:
+    - woodpecker_terraform_vault

policies/kv/service/vault/au/syd1/secret_backend/gitea/config_write.yaml

@@ -0,0 +1,20 @@
+# Allow terraform-git to seed (write once) the gitea secrets engine's admin
+# credentials. terraform-git creates the gitea-vault-admin site-admin bot and
+# writes its generated password here as admin_username + admin_password; the
+# vault gitea engine (managed by the tf_vault deployer) reads it at gitea/config
+# creation time. Read is already granted to the deployer via
+# policies/kv/service/vault/secret_backends_read.yaml, so this only adds the
+# write side for terraform-git's own identity.
+---
+rules:
+  - path: "kv/data/service/vault/au/syd1/secret_backend/gitea/config"
+    capabilities:
+      - create
+      - read
+      - update
+
+auth:
+  approle:
+    - terraform_git
+  k8s/au/syd1:
+    - woodpecker_terraform_git