openhcl_attestation_protocol/igvm_attest/get.rs
1// Copyright (c) Microsoft Corporation.
2// Licensed under the MIT License.
3
4//! The module helps preparing requests and parsing responses that are
5//! sent to and received from the IGVm agent runs on the host via GET
6//! `IGVM_ATTEST` host request.
7
8use bitfield_struct::bitfield;
9use open_enum::open_enum;
10use zerocopy::FromBytes;
11use zerocopy::Immutable;
12use zerocopy::IntoBytes;
13use zerocopy::KnownLayout;
14
15const ATTESTATION_VERSION: u32 = 2;
16const ATTESTATION_SIGNATURE: u32 = 0x414c4348; // 'HCLA'
17/// The value is based on the maximum report size of the supported isolated VM
18/// Currently it's the size of a SNP report.
19const ATTESTATION_REPORT_SIZE_MAX: usize = SNP_VM_REPORT_SIZE;
20
21pub const VBS_VM_REPORT_SIZE: usize = hvdef::vbs::VBS_REPORT_SIZE;
22pub const SNP_VM_REPORT_SIZE: usize = x86defs::snp::SNP_REPORT_SIZE;
23pub const TDX_VM_REPORT_SIZE: usize = x86defs::tdx::TDX_REPORT_SIZE;
24/// No TEE attestation report for TVM
25pub const TVM_REPORT_SIZE: usize = 0;
26
27const PAGE_SIZE: usize = 4096;
28
29/// Number of pages required by the response buffer of WRAPPED_KEY request
30/// Currently the number matches the maximum value defined by `get_protocol`
31pub const WRAPPED_KEY_RESPONSE_BUFFER_SIZE: usize = 16 * PAGE_SIZE;
32/// Number of pages required by the response buffer of KEY_RELEASE request
33/// Currently the number matches the maximum value defined by `get_protocol`
34pub const KEY_RELEASE_RESPONSE_BUFFER_SIZE: usize = 16 * PAGE_SIZE;
35/// Number of pages required by the response buffer of AK_CERT request
36/// Currently the AK cert request only requires 1 page.
37pub const AK_CERT_RESPONSE_BUFFER_SIZE: usize = PAGE_SIZE;
38
39/// Current IGVM Attest response header version.
40pub const IGVM_ATTEST_RESPONSE_CURRENT_VERSION: IgvmAttestResponseVersion =
41 IgvmAttestResponseVersion::VERSION_2;
42
43open_enum! {
44 /// IGVM Attest response header versions.
45 #[derive(Default, IntoBytes, Immutable, KnownLayout, FromBytes)]
46 pub enum IgvmAttestResponseVersion: u32 {
47 /// Version 1
48 VERSION_1 = 1,
49 /// Version 2
50 VERSION_2 = 2,
51 }
52}
53
54/// Current IGVM Attest request header version.
55pub const IGVM_ATTEST_REQUEST_CURRENT_VERSION: IgvmAttestRequestVersion =
56 IgvmAttestRequestVersion::VERSION_2;
57
58open_enum! {
59 /// IGVM Attest request header versions.
60 #[derive(IntoBytes, Immutable, KnownLayout, FromBytes)]
61 pub enum IgvmAttestRequestVersion: u32 {
62 /// Version 1
63 VERSION_1 = 1,
64 /// Version 2
65 VERSION_2 = 2,
66 }
67}
68
69/// Request base structure (C-style)
70/// The struct (includes the appended [`runtime_claims::RuntimeClaims`]) also serves as the
71/// attestation report in vTPM guest attestation.
72#[repr(C)]
73#[derive(Debug, IntoBytes, Immutable, KnownLayout, FromBytes)]
74pub struct IgvmAttestRequestBase {
75 /// Header (unmeasured)
76 pub header: IgvmAttestRequestHeader,
77 /// TEE attestation report
78 pub attestation_report: [u8; ATTESTATION_REPORT_SIZE_MAX],
79 /// Request data (unmeasured)
80 pub request_data: IgvmAttestRequestData,
81 // Data to be appended at the end of the struct:
82 // - Optional Extended request data [`IgvmAttestRequestDataExt`] (request version 2+).
83 // - Variable-length [`runtime_claims::RuntimeClaims`] (JSON string)
84 // The hash of [`runtime_claims::RuntimeClaims`] in [`IgvmAttestHashType`] will be captured
85 // in the `report_data` or equivalent field of the TEE attestation report.
86}
87
88open_enum! {
89 /// TEE attestation report type (C-style enum)
90 #[derive(IntoBytes, Immutable, KnownLayout, FromBytes)]
91 pub enum IgvmAttestReportType: u32 {
92 /// Invalid report
93 INVALID_REPORT = 0,
94 /// VBS report
95 VBS_VM_REPORT = 1,
96 /// SNP report
97 SNP_VM_REPORT = 2,
98 /// Trusted VM report
99 TVM_REPORT = 3,
100 /// TDX report
101 TDX_VM_REPORT = 4,
102 /// CCA report
103 CCA_VM_REPORT = 5,
104 }
105}
106
107open_enum! {
108 /// Request type (C-style enum)
109 #[derive(IntoBytes, Immutable, KnownLayout, FromBytes)]
110 pub enum IgvmAttestRequestType: u32 {
111 /// Invalid request
112 INVALID_REQUEST = 0,
113 /// Request for getting wrapped key from AKV.
114 KEY_RELEASE_REQUEST = 1,
115 /// Request to getting attestation key certificate.
116 AK_CERT_REQUEST = 2,
117 /// Request for getting VMMD blob from CPS.
118 WRAPPED_KEY_REQUEST = 3,
119 }
120}
121
122open_enum! {
123 /// Hash algorithm used for content of report data (C-style enum)
124 #[derive(IntoBytes, Immutable, KnownLayout, FromBytes)]
125 pub enum IgvmAttestHashType: u32 {
126 /// Invalid hash
127 INVALID_HASH = 0,
128 /// SHA-256
129 SHA_256 = 1,
130 /// SHA-384
131 SHA_384 = 2,
132 /// SHA-512
133 SHA_512 = 3,
134 }
135}
136
137/// Unmeasured data used to provide transport sanity and versioning (C-style struct)
138#[repr(C)]
139#[derive(Debug, IntoBytes, Immutable, KnownLayout, FromBytes)]
140pub struct IgvmAttestRequestHeader {
141 /// Signature
142 pub signature: u32,
143 /// Version
144 pub version: u32,
145 /// Report size
146 pub report_size: u32,
147 /// Request type
148 pub request_type: IgvmAttestRequestType,
149 /// Status
150 pub status: u32,
151 /// Reserved
152 pub reserved: [u32; 3],
153}
154
155impl IgvmAttestRequestHeader {
156 /// Create an `HardwareKeyProtectorHeader` instance.
157 pub fn new(report_size: u32, request_type: IgvmAttestRequestType, status: u32) -> Self {
158 Self {
159 signature: ATTESTATION_SIGNATURE,
160 version: ATTESTATION_VERSION,
161 report_size,
162 request_type,
163 status,
164 reserved: [0u32; 3],
165 }
166 }
167}
168
169/// Bitmap of additional Igvm request attributes.
170/// 0 - error_code: Requesting IGVM Agent Error code
171/// 1 - retry: Retry preference
172/// 2 - skip_hw_unsealing: Skip hardware unsealing in case key release request fails
173/// 3 - use_rsa_aes_key_wrap_384: Request that the IGVM Agent ask Azure Key Vault
174/// (AKV) to wrap and release the key with the SHA-384 variant of the
175/// composite RSA+AES key-wrap scheme (PKCS#11 CKM_RSA_AES_KEY_WRAP /
176/// AKV's RSA_AES_KEY_WRAP_384): RSA-OAEP-SHA384 (MGF1-SHA-384) wraps an
177/// AES-256 KEK that performs AES Key Wrap on the released key. The default
178/// is the same CKM_RSA_AES_KEY_WRAP scheme with the inner RSA-OAEP using
179/// SHA-1 (MGF1-SHA-1).
180/// 4 - corim_endorsement: Request that the IGVM Agent fetch the CoRIM launch
181/// endorsement for the guest and include it in the attestation flow.
182#[bitfield(u32)]
183#[derive(IntoBytes, FromBytes, Immutable, KnownLayout)]
184pub struct IgvmCapabilityBitMap {
185 pub error_code: bool,
186 pub retry: bool,
187 pub skip_hw_unsealing: bool,
188 pub use_rsa_aes_key_wrap_384: bool,
189 pub corim_endorsement: bool,
190 #[bits(27)]
191 _reserved: u32,
192}
193
194/// Unmeasured user data, used for host attestation requests (C-style struct)
195#[repr(C)]
196#[derive(Debug, IntoBytes, Immutable, KnownLayout, FromBytes)]
197pub struct IgvmAttestRequestData {
198 /// Data size
199 pub data_size: u32,
200 /// Version
201 pub version: IgvmAttestRequestVersion,
202 /// Report type
203 pub report_type: IgvmAttestReportType,
204 /// Report data hash type
205 pub report_data_hash_type: IgvmAttestHashType,
206 /// Size of the appended raw runtime claims
207 pub variable_data_size: u32,
208}
209
210impl IgvmAttestRequestData {
211 /// Create an `IgvmAttestRequestData` instance.
212 pub fn new(
213 version: IgvmAttestRequestVersion,
214 data_size: u32,
215 report_type: IgvmAttestReportType,
216 report_data_hash_type: IgvmAttestHashType,
217 variable_data_size: u32,
218 ) -> Self {
219 Self {
220 data_size,
221 version,
222 report_type,
223 report_data_hash_type,
224 variable_data_size,
225 }
226 }
227}
228
229/// Unmeasured user data appended to `IgvmAttestRequestData` for version 2+,
230/// used for host attestation requests (C-style struct).
231#[repr(C)]
232#[derive(Debug, IntoBytes, Immutable, KnownLayout, FromBytes)]
233pub struct IgvmAttestRequestDataExt {
234 /// Bitmap of additional requested attributes
235 pub capability_bitmap: IgvmCapabilityBitMap,
236}
237
238impl IgvmAttestRequestDataExt {
239 /// Create an `IgvmAttestRequestDataExt` instance.
240 pub fn new(capability_bitmap: IgvmCapabilityBitMap) -> Self {
241 Self { capability_bitmap }
242 }
243}
244
245/// Bitmap indicates a signal to requestor
246/// 0 - IGVM_SIGNAL_RETRY_RECOMMENDED_BIT: Retry recommendation
247/// 1 - IGVM_SIGNAL_SKIP_HW_UNSEALING_RECOMMENDED_BIT: Skip hardware unsealing
248/// 2 - IGVM_SIGNAL_RSA_AES_KEY_WRAP_384_USED_BIT: Set by the IGVM Agent to
249/// indicate that the agent asked AKV for the SHA-384 variant
250/// (RSA_AES_KEY_WRAP_384) and AKV used it to wrap the key in the payload.
251/// If this bit is clear, AKV wrapped the key with the default
252/// CKM_RSA_AES_KEY_WRAP scheme (inner RSA-OAEP using SHA-1).
253/// 3 - IGVM_SIGNAL_CORIM_ENDORSEMENT_REQUESTED_BIT: Set by the IGVM Agent to
254/// indicate that the agent requested the CoRIM endorsement.
255#[bitfield(u32)]
256#[derive(IntoBytes, Immutable, KnownLayout, FromBytes)]
257pub struct IgvmSignal {
258 pub retry: bool,
259 pub skip_hw_unsealing: bool,
260 pub rsa_aes_key_wrap_384_used: bool,
261 pub corim_endorsement_requested: bool,
262 #[bits(28)]
263 _reserved: u32,
264}
265
266/// The common response header that comply with both V1 and V2 Igvm attest response
267#[repr(C)]
268#[derive(Default, Debug, IntoBytes, FromBytes)]
269pub struct IgvmAttestCommonResponseHeader {
270 /// Data size
271 pub data_size: u32,
272 /// Version
273 pub version: IgvmAttestResponseVersion,
274}
275
276/// The response header for `IGVM_ERROR_INFO` (C-style struct)
277#[repr(C)]
278#[derive(Default, Debug, IntoBytes, Immutable, KnownLayout, FromBytes)]
279pub struct IgvmErrorInfo {
280 /// ErrorCode propagated from IgvmAgent
281 pub error_code: u32,
282 /// HttpStatusCode propagated from IgvmAgent that enhances the ErrorCode
283 pub http_status_code: u32,
284 /// Igvm signal from response
285 pub igvm_signal: IgvmSignal,
286 /// Reserved
287 pub reserved: [u32; 3],
288}
289
290/// The response header for `KEY_RELEASE_REQUEST` (C-style struct)
291#[repr(C)]
292#[derive(Default, Debug, IntoBytes, Immutable, KnownLayout, FromBytes)]
293pub struct IgvmAttestKeyReleaseResponseHeader {
294 /// Data size
295 pub data_size: u32,
296 /// Version
297 pub version: IgvmAttestResponseVersion,
298 /// IgvmErrorInfo that contains RPC result and retry recommendation
299 pub error_info: IgvmErrorInfo,
300}
301
302/// The response header for `WRAPPED_KEY_REQUEST` (C-style struct)
303/// Currently the definition is the same as [`IgvmAttestKeyReleaseResponseHeader`].
304#[repr(C)]
305#[derive(Default, Debug, IntoBytes, Immutable, KnownLayout, FromBytes)]
306pub struct IgvmAttestWrappedKeyResponseHeader {
307 /// Data size
308 pub data_size: u32,
309 /// Version
310 pub version: IgvmAttestResponseVersion,
311 /// IgvmErrorInfo that contains RPC result and retry recommendation
312 pub error_info: IgvmErrorInfo,
313}
314
315/// The response header for `AK_CERT_REQUEST` (C-style struct)
316#[repr(C)]
317#[derive(Default, Debug, IntoBytes, Immutable, KnownLayout, FromBytes)]
318pub struct IgvmAttestAkCertResponseHeader {
319 /// Data size
320 pub data_size: u32,
321 /// Version
322 pub version: IgvmAttestResponseVersion,
323 /// IgvmErrorInfo that contains RPC result and retry recommendation
324 pub error_info: IgvmErrorInfo,
325}
326
327/// Definition of the runt-time claims, which will be appended to the
328/// `IgvmAttestRequestBase` in raw bytes.
329pub mod runtime_claims {
330 use base64_serde::base64_serde_type;
331 use guid::Guid;
332 use mesh::MeshPayload;
333 use serde::Deserialize;
334 use serde::Serialize;
335
336 base64_serde_type!(Base64Url, base64::engine::general_purpose::URL_SAFE_NO_PAD);
337
338 /// Measured runtime claim in JSON format.
339 /// The hash of the data is expected be put into the user_data field of
340 /// the attestation report.
341 #[derive(Debug, Deserialize, Serialize)]
342 #[serde(rename_all = "kebab-case")]
343 pub struct RuntimeClaims {
344 /// An array of [`RsaJwk`]
345 pub keys: Vec<RsaJwk>,
346 /// VM configuration
347 pub vm_configuration: AttestationVmConfig,
348 /// Optional user data
349 #[serde(default, skip_serializing_if = "String::is_empty")]
350 pub user_data: String,
351 }
352
353 impl RuntimeClaims {
354 /// Create runtime claims for `KEY_RELEASE_REQUEST`.
355 pub fn key_release_request_runtime_claims(
356 exponent: &[u8],
357 modulus: &[u8],
358 attestation_vm_config: &AttestationVmConfig,
359 ) -> Self {
360 let transfer_key_jwks = RsaJwk::get_transfer_key_jwks(exponent, modulus);
361 Self {
362 keys: transfer_key_jwks,
363 vm_configuration: attestation_vm_config.clone(),
364 user_data: "".to_string(),
365 }
366 }
367
368 /// Helper function for creating runtime claims of `AK_CERT_REQUEST`.
369 pub fn ak_cert_runtime_claims(
370 ak_pub_exponent: &[u8],
371 ak_pub_modulus: &[u8],
372 ek_pub_exponent: &[u8],
373 ek_pub_modulus: &[u8],
374 attestation_vm_config: &AttestationVmConfig,
375 user_data: &[u8],
376 ) -> Self {
377 let tpm_jwks = RsaJwk::get_tpm_jwks(
378 ak_pub_exponent,
379 ak_pub_modulus,
380 ek_pub_exponent,
381 ek_pub_modulus,
382 );
383 Self {
384 keys: tpm_jwks,
385 vm_configuration: attestation_vm_config.clone(),
386 user_data: hex::encode(user_data),
387 }
388 }
389 }
390
391 /// JWK for an RSA key
392 #[derive(Debug, Deserialize, Serialize)]
393 pub struct RsaJwk {
394 /// Key id
395 pub kid: String,
396 /// Key operations
397 pub key_ops: Vec<String>,
398 /// Key type
399 pub kty: String,
400 /// RSA public exponent
401 #[serde(with = "Base64Url")]
402 pub e: Vec<u8>,
403 /// RSA public modulus
404 #[serde(with = "Base64Url")]
405 pub n: Vec<u8>,
406 }
407
408 impl RsaJwk {
409 /// Create a JWKS from inputs.
410 pub fn get_transfer_key_jwks(exponent: &[u8], modulus: &[u8]) -> Vec<RsaJwk> {
411 let jwk = RsaJwk {
412 kid: "HCLTransferKey".to_string(),
413 key_ops: vec!["encrypt".to_string()],
414 kty: "RSA".to_string(),
415 e: exponent.to_vec(),
416 n: modulus.to_vec(),
417 };
418
419 vec![jwk]
420 }
421
422 /// Create a JWKS from inputs.
423 pub fn get_tpm_jwks(
424 ak_pub_exponent: &[u8],
425 ak_pub_modulus: &[u8],
426 ek_pub_exponent: &[u8],
427 ek_pub_modulus: &[u8],
428 ) -> Vec<RsaJwk> {
429 let ak_pub = RsaJwk {
430 kid: "HCLAkPub".to_string(),
431 key_ops: vec!["sign".to_string()],
432 kty: "RSA".to_string(),
433 e: ak_pub_exponent.to_vec(),
434 n: ak_pub_modulus.to_vec(),
435 };
436 let ek_pub = RsaJwk {
437 kid: "HCLEkPub".to_string(),
438 key_ops: vec!["encrypt".to_string()],
439 kty: "RSA".to_string(),
440 e: ek_pub_exponent.to_vec(),
441 n: ek_pub_modulus.to_vec(),
442 };
443
444 vec![ak_pub, ek_pub]
445 }
446 }
447
448 /// Claims for VMGS provenance.
449 #[derive(Clone, Debug, Deserialize, Serialize, MeshPayload)]
450 #[serde(rename_all = "kebab-case")]
451 pub struct VmgsProvisioner {
452 /// VMGS ID
453 #[serde(with = "serde_helpers::as_string")]
454 pub id: Guid,
455 /// Signer (root cert thumbprint + leaf subject name as a decentralized
456 /// identifier)
457 pub signer: String,
458 }
459
460 /// Supported hardware sealing policy
461 #[derive(Clone, Copy, Debug, Deserialize, Serialize, MeshPayload)]
462 pub enum HardwareSealingPolicy {
463 #[serde(rename = "none")]
464 None,
465 #[serde(rename = "hash")]
466 Hash,
467 #[serde(rename = "signer")]
468 Signer,
469 }
470
471 /// TPM reference implementation version.
472 #[derive(Clone, Copy, Debug, Deserialize, Serialize, MeshPayload)]
473 pub enum AttestationTpmVersion {
474 /// TPM reference implementation version 1.38
475 #[serde(rename = "1.38")]
476 V138,
477 /// TPM reference implementation version 1.85
478 #[serde(rename = "185")]
479 V185,
480 }
481
482 /// VM configuration to be included in the `RuntimeClaims`.
483 #[derive(Clone, Debug, Deserialize, Serialize, MeshPayload)]
484 #[serde(rename_all = "kebab-case")]
485 pub struct AttestationVmConfig {
486 /// Time stamp
487 #[serde(skip_serializing_if = "Option::is_none")]
488 pub current_time: Option<i64>,
489 /// Base64-encoded hash of the provisioning cert
490 pub root_cert_thumbprint: String,
491 /// Whether the serial console is enabled
492 pub console_enabled: bool,
493 /// Whether the serial console, if enabled, is interactive
494 pub interactive_console_enabled: bool,
495 /// Whether the IPMI KCS interface is enabled
496 pub ipmi_enabled: bool,
497 /// Whether secure boot is enabled
498 pub secure_boot: bool,
499 /// Whether the TPM is enabled
500 pub tpm_enabled: bool,
501 /// TPM reference implementation version
502 pub tpm_version: AttestationTpmVersion,
503 /// Whether the VM is in stateful mode (i.e. attestation is not
504 /// suppressed).
505 ///
506 /// NOTE: This is a legacy field. Its name (`tpm-persisted` on the wire)
507 /// predates stateless + hardware sealing and does NOT describe whether
508 /// TPM state is actually persisted to the VMGS at runtime — that broader
509 /// decision is made by the VMM (see `no_persistent_secrets` in
510 /// `underhill_core`). The name and value semantics are kept unchanged to
511 /// preserve the attestation runtime-claims contract and the
512 /// hardware-derived key KDF input.
513 pub tpm_persisted: bool,
514 /// Whether certain vPCI devices are allowed through the device filter
515 pub filtered_vpci_devices_allowed: bool,
516 /// VM id
517 #[serde(rename = "vmUniqueId")]
518 pub vm_unique_id: String,
519 /// VMGS provenance data
520 #[serde(skip_serializing_if = "Option::is_none")]
521 pub vmgs_provisioner: Option<VmgsProvisioner>,
522 /// Hardware sealing policy
523 pub hardware_sealing_policy: HardwareSealingPolicy,
524 }
525}