infrastructure-hardening

Response-side HTTP hardening: security headers + safe-by-default CORS (fail-closed)

What it is for

Response-side HTTP hardening for axum/tower services.

Companion to infrastructure-waf (request-side: signatures, rate-limit, honeypots). This crate owns the response posture — security headers and safe-by-default CORS — with a fail-closed config: a missing or partial config deserializes to a fully hardened posture.

# Ordering (important)

The header layer must be the outermost layer so its headers apply to every response, including short-circuit responses from inner layers such as a WAF 403. With tower::ServiceBuilder the FIRST .layer() is outermost:

use tower::ServiceBuilder;
let svc = ServiceBuilder::new()
.layer(infrastructure_hardening::recommended()) // outermost: headers on ALL responses
// .layer(cors).layer(ceilings).layer(waf)  // inner
.service(router);

Note: chained axum::Router::layer() orders in REVERSE of ServiceBuilder (last-added is outermost), so prefer an explicit ServiceBuilder for the security stack to avoid getting the order backwards.

Capabilities

crate root

Response-side HTTP hardening for axum/tower services.

cors (other)

Safe-by-default CORS builders.

How to use it

No examples/ target and no doctest in this crate's rustdoc. The tests listed under Verification are the closest executable usage.

Module structure

infrastructure_hardening

• cors

Public surface

`crate root`

`cors`

Re-exports. Exported here, defined elsewhere.

Boundary

Depends on no other workspace tier.

Shares tier infrastructure with 82 other crates: infrastructure-acquire, infrastructure-adapters-google-calendar, infrastructure-adapters-google-gmail, infrastructure-adapters-google-places, infrastructure-adapters-google-trends, infrastructure-adapters-shodan, infrastructure-adapters-yelp, infrastructure-agent, … (82 total).

_What this crate deliberately does NOT own is a judgment. No committed registry records one for it, so none is stated here._

Where it sits

Dependencies

Runtime, from outside the workspace.

Development, from outside the workspace.

Build. None.

Depended on by. 2 workspace crates.

Signal flow — what reaches this crate, and what it reaches.

flowchart LR
  n_application_security["application-security"] -->|uses| SELF
  n_infrastructure_security_scan["infrastructure-security-scan"] -->|uses| SELF
  SELF["infrastructure-hardening"]
  classDef self fill:#1f883d,stroke:#1f883d,color:#fff;
  class SELF self;

Feature flags

No Cargo features are defined: every capability is unconditional, so no consumer can receive a half-wired crate.

Targets

Error model

No public error type was detected: no public item declares a type named *Error, and no public signature returns one.

Operational characteristics

No unsafe block, unsafe fn, unsafe impl or unsafe trait was found by the parser anywhere in this crate's source.

Configuration

No environment variable is read with a literal name anywhere in this crate. A variable whose key is computed at run time cannot be listed here, and is not claimed to be absent.

Related capabilities

2 workspace crates depend on this one: application-security, infrastructure-security-scan.

Verification

Evidence by module. How often each public module is named by something executable.

What the tests establish, by name:

• deny_frame_option_serializes — src/config.rs
• empty_config_is_fail_closed — src/config.rs
• header_map_has_secure_defaults — src/config.rs
• unknown_field_is_rejected — src/config.rs
• allowlist_allows_listed_origin_and_blocks_others — src/cors.rs
• credentialed_allowlist_scopes_credentials_to_listed_origins — src/cors.rs
• reflect_any_origin_mirrors_but_never_carries_credentials — src/cors.rs
• headers_applied_even_to_403_block — src/headers.rs
• headers_applied_to_inner_response — src/headers.rs

Documentation coverage

pie showData
    title Public items with rustdoc
    "Documented" : 4
    "No rustdoc detected" : 0

Metrics

pie showData
    title Public API by kind
    "function" : 4

pie showData
    title Rust source composition
    "Code" : 331
    "Blank or comment" : 127

Generation

Rendered by tools-corpus corpus readme from repository evidence alone, renderer schema 2, lexicon current. No model, network service or database was consulted. Regenerate with tools-corpus corpus readme --write; verify with --check.