Signed-off-by: Alistair Francis <alistair@xxxxxxxxxxxxx> --- lib/rspdm/consts.rs | 2 + lib/rspdm/lib.rs | 11 ++++ lib/rspdm/state.rs | 123 ++++++++++++++++++++++++++++++++++++++++- lib/rspdm/validator.rs | 64 ++++++++++++++++++++- 4 files changed, 196 insertions(+), 4 deletions(-) diff --git a/lib/rspdm/consts.rs b/lib/rspdm/consts.rs index 9714fa52e2be..ffaf36ec583b 100644 --- a/lib/rspdm/consts.rs +++ b/lib/rspdm/consts.rs @@ -96,6 +96,8 @@ pub(crate) enum SpdmErrorCode { pub(crate) const SPDM_GET_DIGESTS: u8 = 0x81; +pub(crate) const SPDM_GET_CERTIFICATE: u8 = 0x82; + #[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 bf5f7c72f885..1535e3a69518 100644 --- a/lib/rspdm/lib.rs +++ b/lib/rspdm/lib.rs @@ -126,6 +126,17 @@ return e.to_errno() as c_int; } + let mut provisioned_slots = state.provisioned_slots; + while (provisioned_slots as usize) > 0 { + let slot = provisioned_slots.trailing_zeros() as u8; + + if let Err(e) = state.get_certificate(slot) { + return e.to_errno() as c_int; + } + + provisioned_slots &= !(1 << slot); + } + 0 } diff --git a/lib/rspdm/state.rs b/lib/rspdm/state.rs index 7889214c6aa7..ae259623fe50 100644 --- a/lib/rspdm/state.rs +++ b/lib/rspdm/state.rs @@ -26,8 +26,9 @@ SPDM_REQ, SPDM_RSP_MIN_CAPS, SPDM_SLOTS, SPDM_VER_10, SPDM_VER_11, SPDM_VER_12, }; use crate::validator::{ - GetCapabilitiesReq, GetCapabilitiesRsp, GetDigestsReq, GetDigestsRsp, GetVersionReq, - GetVersionRsp, NegotiateAlgsReq, NegotiateAlgsRsp, RegAlg, SpdmErrorRsp, SpdmHeader, + GetCapabilitiesReq, GetCapabilitiesRsp, GetCertificateReq, GetCertificateRsp, GetDigestsReq, + GetDigestsRsp, GetVersionReq, GetVersionRsp, NegotiateAlgsReq, NegotiateAlgsRsp, RegAlg, + SpdmErrorRsp, SpdmHeader, }; /// The current SPDM session state for a device. Based on the @@ -112,6 +113,14 @@ pub struct SpdmState { slot_sz: [usize; SPDM_SLOTS], } +#[repr(C, packed)] +pub(crate) struct SpdmCertChain { + length: u16, + _reserved: [u8; 2], + root_hash: bindings::__IncompleteArrayField<u8>, + certificates: bindings::__IncompleteArrayField<u8>, +} + impl SpdmState { pub(crate) fn new( dev: *mut bindings::device, @@ -626,4 +635,114 @@ pub(crate) fn get_digests(&mut self) -> Result<(), Error> { Ok(()) } + + fn get_cert_exchange( + &mut self, + request_buf: &mut [u8], + response_vec: &mut KVec<u8>, + rsp_sz: usize, + ) -> Result<&mut GetCertificateRsp, Error> { + // 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::<GetCertificateReq>() as i32) { + pr_err!("Truncated certificate 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 GetCertificateRsp = Untrusted::new_mut(response_vec).validate_mut()?; + + if rc + < (core::mem::size_of::<GetCertificateRsp>() + response.portion_length as usize) as i32 + { + pr_err!("Truncated certificate response\n"); + to_result(-(bindings::EIO as i32))?; + } + + Ok(response) + } + + pub(crate) fn get_certificate(&mut self, slot: u8) -> Result<(), Error> { + let mut request = GetCertificateReq::default(); + request.version = self.version; + request.param1 = slot; + + let req_sz = core::mem::size_of::<GetCertificateReq>(); + let rsp_sz = ((core::mem::size_of::<GetCertificateRsp>() + 0xffff) as u32) + .min(self.transport_sz) as usize; + + // 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)?; + + request.offset = 0; + request.length = (rsp_sz - core::mem::size_of::<GetCertificateRsp>()).to_le() as u16; + + let response = self.get_cert_exchange(request_buf, &mut response_vec, rsp_sz)?; + + let total_cert_len = + ((response.portion_length + response.remainder_length) & 0xFFFF) as usize; + + let mut certs_buf: KVec<u8> = KVec::new(); + + certs_buf.extend_from_slice( + &response_vec[8..(8 + response.portion_length as usize)], + GFP_KERNEL, + )?; + + let mut offset: usize = response.portion_length as usize; + let mut remainder_length = response.remainder_length as usize; + + while remainder_length > 0 { + request.offset = offset.to_le() as u16; + request.length = (remainder_length + .min(rsp_sz - core::mem::size_of::<GetCertificateRsp>())) + .to_le() as u16; + + let response = self.get_cert_exchange(request_buf, &mut response_vec, rsp_sz)?; + + if response.portion_length == 0 + || (response.param1 & 0xF) != slot + || offset as u16 + response.portion_length + response.remainder_length + != total_cert_len as u16 + { + pr_err!("Malformed certificate response\n"); + to_result(-(bindings::EPROTO as i32))?; + } + + certs_buf.extend_from_slice( + &response_vec[8..(8 + response.portion_length as usize)], + GFP_KERNEL, + )?; + offset += response.portion_length as usize; + remainder_length = response.remainder_length as usize; + } + + let header_length = core::mem::size_of::<SpdmCertChain>() + self.hash_len; + + let ptr = certs_buf.as_mut_ptr(); + // SAFETY: `SpdmCertChain` is repr(C) and packed, so we can convert it from a slice + let ptr = ptr.cast::<SpdmCertChain>(); + // SAFETY: `ptr` came from a reference and the cast above is valid. + let certs: &mut SpdmCertChain = unsafe { &mut *ptr }; + + if total_cert_len < header_length + || total_cert_len != usize::from_le(certs.length as usize) + || total_cert_len != certs_buf.len() + { + pr_err!("Malformed certificate chain in slot {slot}\n"); + to_result(-(bindings::EPROTO as i32))?; + } + + self.slot_sz[slot as usize] = total_cert_len; + self.slot[slot as usize] = Some(certs_buf); + + Ok(()) + } } diff --git a/lib/rspdm/validator.rs b/lib/rspdm/validator.rs index 2150a23997db..a8bc3378676f 100644 --- a/lib/rspdm/validator.rs +++ b/lib/rspdm/validator.rs @@ -17,8 +17,9 @@ }; use crate::consts::{ - 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, + SPDM_ASYM_ALGOS, SPDM_CTEXPONENT, SPDM_GET_CAPABILITIES, SPDM_GET_CERTIFICATE, + SPDM_GET_DIGESTS, SPDM_GET_VERSION, SPDM_HASH_ALGOS, SPDM_MEAS_SPEC_DMTF, SPDM_NEGOTIATE_ALGS, + SPDM_REQ_CAPS, }; #[repr(C, packed)] @@ -364,3 +365,62 @@ fn validate(unvalidated: &mut Unvalidated<KVec<u8>>) -> Result<Self, Self::Err> Ok(rsp) } } + +#[repr(C, packed)] +pub(crate) struct GetCertificateReq { + pub(crate) version: u8, + pub(crate) code: u8, + pub(crate) param1: u8, + pub(crate) param2: u8, + + pub(crate) offset: u16, + pub(crate) length: u16, +} + +impl Default for GetCertificateReq { + fn default() -> Self { + GetCertificateReq { + version: 0, + code: SPDM_GET_CERTIFICATE, + param1: 0, + param2: 0, + offset: 0, + length: 0, + } + } +} + +#[repr(C, packed)] +pub(crate) struct GetCertificateRsp { + pub(crate) version: u8, + pub(crate) code: u8, + pub(crate) param1: u8, + pub(crate) param2: u8, + + pub(crate) portion_length: u16, + pub(crate) remainder_length: u16, + + pub(crate) cert_chain: __IncompleteArrayField<u8>, +} + +impl Validate<&mut Unvalidated<KVec<u8>>> for &mut GetCertificateRsp { + 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::<GetCertificateRsp>() { + return Err(EINVAL); + } + + let ptr = raw.as_mut_ptr(); + // CAST: `GetCertificateRsp` only contains integers and has `repr(C)`. + let ptr = ptr.cast::<GetCertificateRsp>(); + // SAFETY: `ptr` came from a reference and the cast above is valid. + let rsp: &mut GetCertificateRsp = unsafe { &mut *ptr }; + + rsp.portion_length = rsp.portion_length.to_le(); + rsp.remainder_length = rsp.remainder_length.to_le(); + + Ok(rsp) + } +} -- 2.48.1