Signed-off-by: Alistair Francis <alistair@xxxxxxxxxxxxx> --- lib/rspdm/consts.rs | 4 ++ lib/rspdm/lib.rs | 4 ++ lib/rspdm/state.rs | 89 ++++++++++++++++++++++++++++++++++++++++-- lib/rspdm/validator.rs | 52 +++++++++++++++++++++++- 4 files changed, 144 insertions(+), 5 deletions(-) diff --git a/lib/rspdm/consts.rs b/lib/rspdm/consts.rs index d2f245c858cc..9714fa52e2be 100644 --- a/lib/rspdm/consts.rs +++ b/lib/rspdm/consts.rs @@ -16,6 +16,8 @@ pub(crate) const SPDM_VER_12: u8 = 0x12; pub(crate) const SPDM_VER_13: u8 = 0x13; +pub(crate) const SPDM_SLOTS: usize = 8; + pub(crate) const SPDM_MIN_VER: u8 = SPDM_VER_10; pub(crate) const SPDM_MAX_VER: u8 = SPDM_VER_13; @@ -92,6 +94,8 @@ pub(crate) enum SpdmErrorCode { pub(crate) const SPDM_HASH_SHA_384: u32 = 1 << 1; pub(crate) const SPDM_HASH_SHA_512: u32 = 1 << 2; +pub(crate) const SPDM_GET_DIGESTS: u8 = 0x81; + #[cfg(CONFIG_CRYPTO_RSA)] pub(crate) const SPDM_ASYM_RSA: u32 = SPDM_ASYM_RSASSA_2048 | SPDM_ASYM_RSASSA_3072 | SPDM_ASYM_RSASSA_4096; diff --git a/lib/rspdm/lib.rs b/lib/rspdm/lib.rs index 5eee5116d791..bf5f7c72f885 100644 --- a/lib/rspdm/lib.rs +++ b/lib/rspdm/lib.rs @@ -122,6 +122,10 @@ return e.to_errno() as c_int; } + if let Err(e) = state.get_digests() { + return e.to_errno() as c_int; + } + 0 } diff --git a/lib/rspdm/state.rs b/lib/rspdm/state.rs index 0aff45339e0b..7889214c6aa7 100644 --- a/lib/rspdm/state.rs +++ b/lib/rspdm/state.rs @@ -23,11 +23,11 @@ SPDM_ASYM_RSASSA_4096, SPDM_ERROR, SPDM_GET_VERSION_LEN, SPDM_HASH_ALGOS, SPDM_HASH_SHA_256, SPDM_HASH_SHA_384, SPDM_HASH_SHA_512, SPDM_KEY_EX_CAP, SPDM_MAX_VER, SPDM_MEAS_CAP_MASK, SPDM_MEAS_SPEC_DMTF, SPDM_MIN_DATA_TRANSFER_SIZE, SPDM_MIN_VER, SPDM_OPAQUE_DATA_FMT_GENERAL, - SPDM_REQ, SPDM_RSP_MIN_CAPS, SPDM_VER_10, SPDM_VER_11, SPDM_VER_12, + SPDM_REQ, SPDM_RSP_MIN_CAPS, SPDM_SLOTS, SPDM_VER_10, SPDM_VER_11, SPDM_VER_12, }; use crate::validator::{ - GetCapabilitiesReq, GetCapabilitiesRsp, GetVersionReq, GetVersionRsp, NegotiateAlgsReq, - NegotiateAlgsRsp, RegAlg, SpdmErrorRsp, SpdmHeader, + GetCapabilitiesReq, GetCapabilitiesRsp, GetDigestsReq, GetDigestsRsp, GetVersionReq, + GetVersionRsp, NegotiateAlgsReq, NegotiateAlgsRsp, RegAlg, SpdmErrorRsp, SpdmHeader, }; /// The current SPDM session state for a device. Based on the @@ -54,6 +54,10 @@ /// Selected by responder during NEGOTIATE_ALGORITHMS exchange. /// @meas_hash_alg: Hash algorithm for measurement blocks. /// Selected by responder during NEGOTIATE_ALGORITHMS exchange. +/// @supported_slots: Bitmask of responder's supported certificate slots. +/// Received during GET_DIGESTS exchange (from SPDM 1.3). +/// @provisioned_slots: Bitmask of responder's provisioned certificate slots. +/// Received during GET_DIGESTS exchange. /// @base_asym_enc: Human-readable name of @base_asym_alg's signature encoding. /// Passed to crypto subsystem when calling verify_signature(). /// @sig_len: Signature length of @base_asym_alg (in bytes). @@ -68,6 +72,9 @@ /// @desc: Synchronous hash context for @base_hash_alg computation. /// @hash_len: Hash length of @base_hash_alg (in bytes). /// H in SPDM specification. +/// @slot: Certificate chain in each of the 8 slots. NULL pointer if a slot is +/// not populated. Prefixed by the 4 + H header per SPDM 1.0.0 table 15. +/// @slot_sz: Certificate chain size (in bytes). /// /// `authenticated`: Whether device was authenticated successfully. #[expect(dead_code)] @@ -85,6 +92,8 @@ pub struct SpdmState { pub(crate) base_asym_alg: u32, pub(crate) base_hash_alg: u32, pub(crate) meas_hash_alg: u32, + pub(crate) supported_slots: u8, + pub(crate) provisioned_slots: u8, /* Signature algorithm */ base_asym_enc: &'static CStr, @@ -97,6 +106,10 @@ pub struct SpdmState { pub(crate) hash_len: usize, pub(crate) authenticated: bool, + + // Certificates + pub(crate) slot: [Option<KVec<u8>>; SPDM_SLOTS], + slot_sz: [usize; SPDM_SLOTS], } impl SpdmState { @@ -120,6 +133,8 @@ pub(crate) fn new( base_asym_alg: 0, base_hash_alg: 0, meas_hash_alg: 0, + supported_slots: 0, + provisioned_slots: 0, base_asym_enc: unsafe { CStr::from_bytes_with_nul_unchecked(b"\0") }, sig_len: 0, base_hash_alg_name: unsafe { CStr::from_bytes_with_nul_unchecked(b"\0") }, @@ -127,6 +142,8 @@ pub(crate) fn new( desc: None, hash_len: 0, authenticated: false, + slot: [const { None }; SPDM_SLOTS], + slot_sz: [0; SPDM_SLOTS], } } @@ -543,4 +560,70 @@ pub(crate) fn negotiate_algs(&mut self) -> Result<(), Error> { Ok(()) } + + pub(crate) fn get_digests(&mut self) -> Result<(), Error> { + let mut request = GetDigestsReq::default(); + request.version = self.version; + + let req_sz = core::mem::size_of::<GetDigestsReq>(); + let rsp_sz = core::mem::size_of::<GetDigestsRsp>() + SPDM_SLOTS * self.hash_len; + + // SAFETY: `request` is repr(C) and packed, so we can convert it to a slice + let request_buf = unsafe { from_raw_parts_mut(&mut request as *mut _ as *mut u8, req_sz) }; + + let mut response_vec: KVec<u8> = KVec::with_capacity(rsp_sz, GFP_KERNEL)?; + // SAFETY: `request` is repr(C) and packed, so we can convert it to a slice + let response_buf = unsafe { from_raw_parts_mut(response_vec.as_mut_ptr(), rsp_sz) }; + + let rc = self.spdm_exchange(request_buf, response_buf)?; + + if rc < (core::mem::size_of::<GetDigestsRsp>() as i32) { + pr_err!("Truncated digests response\n"); + to_result(-(bindings::EIO as i32))?; + } + + // SAFETY: `rc` bytes where inserted to the raw pointer by spdm_exchange + unsafe { response_vec.set_len(rc as usize) }; + + let response: &mut GetDigestsRsp = Untrusted::new_mut(&mut response_vec).validate_mut()?; + + if rc + < (core::mem::size_of::<GetDigestsReq>() + + response.param2.count_ones() as usize * self.hash_len) as i32 + { + pr_err!("Truncated digests response\n"); + to_result(-(bindings::EIO as i32))?; + } + + let mut deprovisioned_slots = self.provisioned_slots & !response.param2; + while (deprovisioned_slots.trailing_zeros() as usize) < SPDM_SLOTS { + let slot = deprovisioned_slots.trailing_zeros() as usize; + self.slot[slot] = None; + self.slot_sz[slot] = 0; + deprovisioned_slots &= !(1 << slot); + } + + self.provisioned_slots = response.param2; + if self.provisioned_slots == 0 { + pr_err!("No certificates provisioned\n"); + to_result(-(bindings::EPROTO as i32))?; + } + + if self.version >= 0x13 && (response.param2 & !response.param1 != 0) { + pr_err!("Malformed digests response\n"); + to_result(-(bindings::EPROTO as i32))?; + } + + let supported_slots = if self.version >= 0x13 { + response.param1 + } else { + 0xFF + }; + + if self.supported_slots != supported_slots { + self.supported_slots = supported_slots; + } + + Ok(()) + } } diff --git a/lib/rspdm/validator.rs b/lib/rspdm/validator.rs index 036a077c71c3..2150a23997db 100644 --- a/lib/rspdm/validator.rs +++ b/lib/rspdm/validator.rs @@ -17,8 +17,8 @@ }; use crate::consts::{ - SPDM_ASYM_ALGOS, SPDM_CTEXPONENT, SPDM_GET_CAPABILITIES, SPDM_GET_VERSION, SPDM_HASH_ALGOS, - SPDM_MEAS_SPEC_DMTF, SPDM_NEGOTIATE_ALGS, SPDM_REQ_CAPS, + SPDM_ASYM_ALGOS, SPDM_CTEXPONENT, SPDM_GET_CAPABILITIES, SPDM_GET_DIGESTS, SPDM_GET_VERSION, + SPDM_HASH_ALGOS, SPDM_MEAS_SPEC_DMTF, SPDM_NEGOTIATE_ALGS, SPDM_REQ_CAPS, }; #[repr(C, packed)] @@ -316,3 +316,51 @@ fn validate(unvalidated: &mut Unvalidated<KVec<u8>>) -> Result<Self, Self::Err> Ok(rsp) } } + +#[repr(C, packed)] +pub(crate) struct GetDigestsReq { + pub(crate) version: u8, + pub(crate) code: u8, + pub(crate) param1: u8, + pub(crate) param2: u8, +} + +impl Default for GetDigestsReq { + fn default() -> Self { + GetDigestsReq { + version: 0, + code: SPDM_GET_DIGESTS, + param1: 0, + param2: 0, + } + } +} + +#[repr(C, packed)] +pub(crate) struct GetDigestsRsp { + pub(crate) version: u8, + pub(crate) code: u8, + pub(crate) param1: u8, + pub(crate) param2: u8, + + pub(crate) digests: __IncompleteArrayField<u8>, +} + +impl Validate<&mut Unvalidated<KVec<u8>>> for &mut GetDigestsRsp { + type Err = Error; + + fn validate(unvalidated: &mut Unvalidated<KVec<u8>>) -> Result<Self, Self::Err> { + let raw = unvalidated.raw_mut(); + if raw.len() < mem::size_of::<GetDigestsRsp>() { + return Err(EINVAL); + } + + let ptr = raw.as_mut_ptr(); + // CAST: `GetDigestsRsp` only contains integers and has `repr(C)`. + let ptr = ptr.cast::<GetDigestsRsp>(); + // SAFETY: `ptr` came from a reference and the cast above is valid. + let rsp: &mut GetDigestsRsp = unsafe { &mut *ptr }; + + Ok(rsp) + } +} -- 2.48.1