Add bounded structured crypto operations

site/doc/areas/noise.txt

@@ -14,6 +14,7 @@ hmac_sha256
 hmac_sha256_hex
 random_bytes
 crypto_equal
+crypto_operation
 password_hash
 password_verify
 password_needs_rehash

site/doc/pages/crypto_operation.txt

@@ -0,0 +1,28 @@
+:sig
+DValue crypto_operation(DValue request)
+
+:params
+request : structured operation, algorithm, and operation-specific fields
+return value : map with ok, bounded error code, and operation-specific output
+
+:content
+Runs one explicitly supported structured asymmetric cryptographic operation. The initial allowlist is `key_generate` with `ES256` and `jwt_sign` with `ES256`. Unknown operations and algorithms fail closed.
+
+ES256 signing validates that `x`, `y`, and `d` form one P-256 key, forces the protected `alg` to `ES256`, and emits a compact JWT with a 64-byte JOSE signature. Requests, nesting, values, and output are bounded. Header and claims roots must be JSON objects containing valid UTF-8 without raw control bytes.
+
+This function does not replace typed digest, HMAC, password, randomness, or constant-time comparison APIs. It exposes no raw signing, arbitrary curve/digest selection, encryption, or generic OpenSSL access. Keep returned private JWKs secret.
+
+:example
+DValue key_request;
+key_request["operation"] = "key_generate";
+key_request["algorithm"] = "ES256";
+DValue key = crypto_operation(key_request);
+
+DValue sign_request;
+sign_request["operation"] = "jwt_sign";
+sign_request["algorithm"] = "ES256";
+sign_request["private_jwk"] = key["private_jwk"];
+sign_request["protected_header"]["typ"] = "JWT";
+sign_request["claims"]["iss"] = "https://client.example";
+DValue signed_jwt = crypto_operation(sign_request);
+print(signed_jwt["ok"].to_bool() ? "signed" : "failed", "\n");

site/tests/crypto_operation.uce

@@ -0,0 +1,61 @@
+#include "testlib.h"
+
+RENDER(Request& context)
+{
+	u64 passed = 0;
+	u64 failed = 0;
+	u64 skipped = 0;
+	auto check = [&](String name, bool ok, String detail)
+	{
+		site_tests_case(name, ok ? "pass" : "fail", detail);
+		if(ok) passed++; else failed++;
+	};
+	site_tests_page_start("Structured crypto operations", "Algorithm-selected P-256 JWK creation and ES256 JWT signing.");
+	DValue key_request;
+	key_request["operation"] = "key_generate";
+	key_request["algorithm"] = "ES256";
+	DValue key = crypto_operation(key_request);
+	DValue header;
+	header["alg"] = "none";
+	header["kid"] = key["kid"];
+	DValue claims;
+	claims["iss"] = "https://client.example";
+	claims["sub"] = "client.example";
+	DValue sign_request;
+	sign_request["operation"] = "jwt_sign";
+	sign_request["algorithm"] = "ES256";
+	sign_request["private_jwk"] = key["private_jwk"];
+	sign_request["protected_header"] = header;
+	sign_request["claims"] = claims;
+	DValue signed_result = crypto_operation(sign_request);
+	String jwt = signed_result["jwt"].to_string();
+	StringList parts = split(jwt, ".");
+	String header_b64 = parts.size() == 3 ? parts[0] : "";
+	while(header_b64.size() % 4) header_b64 += "=";
+	String decoded_header = base64_decode(header_b64);
+	DValue wrong_curve = key["private_jwk"];
+	wrong_curve["crv"] = "P-384";
+	DValue malformed = key["private_jwk"];
+	malformed["x"] = "not_base64url=";
+	DValue wrong_request = sign_request;
+	wrong_request["private_jwk"] = wrong_curve;
+	DValue malformed_request = sign_request;
+	malformed_request["private_jwk"] = malformed;
+	DValue unsupported;
+	unsupported["operation"] = "encrypt";
+	unsupported["algorithm"] = "ES256";
+	DValue list_header;
+	list_header.set_array();
+	DValue list_item;
+	list_item = "not-an-object";
+	list_header.push(list_item);
+	DValue list_request = sign_request;
+	list_request["protected_header"] = list_header;
+	DValue control_request = sign_request;
+	control_request["claims"]["bad"] = String("control\nbyte");
+	DValue oversized = key_request;
+	oversized["ignored"] = String(17000, 'x');
+	check("crypto_operation() ES256 key generation and JWT signing", key["ok"].to_bool() && signed_result["ok"].to_bool() && key["private_jwk"]["kty"].to_string() == "EC" && key["private_jwk"]["crv"].to_string() == "P-256" && key["public_jwk"]["d"].to_string() == "" && key["kid"].to_string() == key["thumbprint"].to_string() && parts.size() == 3 && parts[2].size() == 86 && decoded_header.find("ES256") != String::npos && !crypto_operation(wrong_request)["ok"].to_bool() && !crypto_operation(malformed_request)["ok"].to_bool() && crypto_operation(unsupported)["error"].to_string() == "unsupported_operation" && !crypto_operation(list_request)["ok"].to_bool() && crypto_operation(control_request)["error"].to_string() == "invalid_request" && crypto_operation(oversized)["error"].to_string() == "invalid_request", key["kid"].to_string());
+	site_tests_summary(passed, failed, skipped, "Structured crypto tests generate ephemeral P-256 keys and retain no key material.");
+	site_tests_page_end();
+}

site/tests/manifest.txt

@@ -8,6 +8,7 @@ markdown.uce|Markdown|Markdown parsing, rendering, and component hooks.|http sui
 units.uce|Units|unit_call(), lifecycle hooks, and unit metadata.|http suite uce public|Units|1|1
 websockets.ws.uce|WebSockets|Browser-driven WebSocket helper checks.|http suite uce public websocket|WebSockets|1|1
 io.uce|Filesystem|Filesystem helpers that are restricted outside trusted networks.|http suite uce internal|Filesystem|1|1
+crypto_operation.uce|Structured Crypto|Algorithm-selected key generation and JWT signing coverage.|http suite uce public crypto|Structured crypto operations|1|1
 sqlite.uce|SQLite|SQLite connector with prepared named parameters and DValue rows.|http suite uce internal sqlite|SQLite|1|1
 zip.uce|ZIP|Archive helpers that create and extract temporary server-side files.|http suite uce internal|ZIP|1|1
 services.uce|Sockets And Services|Network/service helpers that are restricted outside trusted networks.|http suite uce internal|Sockets And Services|1|1