diff options
Diffstat (limited to 'drivers/virt')
| -rw-r--r-- | drivers/virt/coco/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/virt/coco/Makefile | 1 | ||||
| -rw-r--r-- | drivers/virt/coco/pkvm-guest/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/virt/coco/pkvm-guest/Makefile | 2 | ||||
| -rw-r--r-- | drivers/virt/coco/pkvm-guest/arm-pkvm-guest.c | 127 | ||||
| -rw-r--r-- | drivers/virt/coco/sev-guest/sev-guest.c | 132 |
6 files changed, 210 insertions, 64 deletions
diff --git a/drivers/virt/coco/Kconfig b/drivers/virt/coco/Kconfig index 87d142c1f932..d9ff676bf48d 100644 --- a/drivers/virt/coco/Kconfig +++ b/drivers/virt/coco/Kconfig @@ -9,6 +9,8 @@ config TSM_REPORTS source "drivers/virt/coco/efi_secret/Kconfig" +source "drivers/virt/coco/pkvm-guest/Kconfig" + source "drivers/virt/coco/sev-guest/Kconfig" source "drivers/virt/coco/tdx-guest/Kconfig" diff --git a/drivers/virt/coco/Makefile b/drivers/virt/coco/Makefile index 18c1aba5edb7..b69c30c1c720 100644 --- a/drivers/virt/coco/Makefile +++ b/drivers/virt/coco/Makefile @@ -4,5 +4,6 @@ # obj-$(CONFIG_TSM_REPORTS) += tsm.o obj-$(CONFIG_EFI_SECRET) += efi_secret/ +obj-$(CONFIG_ARM_PKVM_GUEST) += pkvm-guest/ obj-$(CONFIG_SEV_GUEST) += sev-guest/ obj-$(CONFIG_INTEL_TDX_GUEST) += tdx-guest/ diff --git a/drivers/virt/coco/pkvm-guest/Kconfig b/drivers/virt/coco/pkvm-guest/Kconfig new file mode 100644 index 000000000000..d2f344f1f98f --- /dev/null +++ b/drivers/virt/coco/pkvm-guest/Kconfig @@ -0,0 +1,10 @@ +config ARM_PKVM_GUEST + bool "Arm pKVM protected guest driver" + depends on ARM64 + help + Protected guests running under the pKVM hypervisor on arm64 + are isolated from the host and must issue hypercalls to enable + interaction with virtual devices. This driver implements + support for probing and issuing these hypercalls. + + If unsure, say 'N'. diff --git a/drivers/virt/coco/pkvm-guest/Makefile b/drivers/virt/coco/pkvm-guest/Makefile new file mode 100644 index 000000000000..4bee24579423 --- /dev/null +++ b/drivers/virt/coco/pkvm-guest/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +obj-$(CONFIG_ARM_PKVM_GUEST) += arm-pkvm-guest.o diff --git a/drivers/virt/coco/pkvm-guest/arm-pkvm-guest.c b/drivers/virt/coco/pkvm-guest/arm-pkvm-guest.c new file mode 100644 index 000000000000..56a3859dda8a --- /dev/null +++ b/drivers/virt/coco/pkvm-guest/arm-pkvm-guest.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Support for the hypercall interface exposed to protected guests by + * pKVM. + * + * Author: Will Deacon <will@kernel.org> + * Copyright (C) 2024 Google LLC + */ + +#include <linux/arm-smccc.h> +#include <linux/array_size.h> +#include <linux/io.h> +#include <linux/mem_encrypt.h> +#include <linux/mm.h> +#include <linux/pgtable.h> + +#include <asm/hypervisor.h> + +static size_t pkvm_granule; + +static int arm_smccc_do_one_page(u32 func_id, phys_addr_t phys) +{ + phys_addr_t end = phys + PAGE_SIZE; + + while (phys < end) { + struct arm_smccc_res res; + + arm_smccc_1_1_invoke(func_id, phys, 0, 0, &res); + if (res.a0 != SMCCC_RET_SUCCESS) + return -EPERM; + + phys += pkvm_granule; + } + + return 0; +} + +static int __set_memory_range(u32 func_id, unsigned long start, int numpages) +{ + void *addr = (void *)start, *end = addr + numpages * PAGE_SIZE; + + while (addr < end) { + int err; + + err = arm_smccc_do_one_page(func_id, virt_to_phys(addr)); + if (err) + return err; + + addr += PAGE_SIZE; + } + + return 0; +} + +static int pkvm_set_memory_encrypted(unsigned long addr, int numpages) +{ + return __set_memory_range(ARM_SMCCC_VENDOR_HYP_KVM_MEM_UNSHARE_FUNC_ID, + addr, numpages); +} + +static int pkvm_set_memory_decrypted(unsigned long addr, int numpages) +{ + return __set_memory_range(ARM_SMCCC_VENDOR_HYP_KVM_MEM_SHARE_FUNC_ID, + addr, numpages); +} + +static const struct arm64_mem_crypt_ops pkvm_crypt_ops = { + .encrypt = pkvm_set_memory_encrypted, + .decrypt = pkvm_set_memory_decrypted, +}; + +static int mmio_guard_ioremap_hook(phys_addr_t phys, size_t size, + pgprot_t *prot) +{ + phys_addr_t end; + pteval_t protval = pgprot_val(*prot); + + /* + * We only expect MMIO emulation for regions mapped with device + * attributes. + */ + if (protval != PROT_DEVICE_nGnRE && protval != PROT_DEVICE_nGnRnE) + return 0; + + phys = PAGE_ALIGN_DOWN(phys); + end = phys + PAGE_ALIGN(size); + + while (phys < end) { + const int func_id = ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_FUNC_ID; + int err; + + err = arm_smccc_do_one_page(func_id, phys); + if (err) + return err; + + phys += PAGE_SIZE; + } + + return 0; +} + +void pkvm_init_hyp_services(void) +{ + int i; + struct arm_smccc_res res; + const u32 funcs[] = { + ARM_SMCCC_KVM_FUNC_HYP_MEMINFO, + ARM_SMCCC_KVM_FUNC_MEM_SHARE, + ARM_SMCCC_KVM_FUNC_MEM_UNSHARE, + }; + + for (i = 0; i < ARRAY_SIZE(funcs); ++i) { + if (!kvm_arm_hyp_service_available(funcs[i])) + return; + } + + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_HYP_MEMINFO_FUNC_ID, + 0, 0, 0, &res); + if (res.a0 > PAGE_SIZE) /* Includes error codes */ + return; + + pkvm_granule = res.a0; + arm64_mem_crypt_ops_register(&pkvm_crypt_ops); + + if (kvm_arm_hyp_service_available(ARM_SMCCC_KVM_FUNC_MMIO_GUARD)) + arm64_ioremap_prot_hook_register(&mmio_guard_ioremap_hook); +} diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c index 6fc7884ea0a1..89754b019be2 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.c +++ b/drivers/virt/coco/sev-guest/sev-guest.c @@ -114,7 +114,7 @@ static bool is_vmpck_empty(struct snp_guest_dev *snp_dev) */ static void snp_disable_vmpck(struct snp_guest_dev *snp_dev) { - dev_alert(snp_dev->dev, "Disabling vmpck_id %d to prevent IV reuse.\n", + dev_alert(snp_dev->dev, "Disabling VMPCK%d communication key to prevent IV reuse.\n", vmpck_id); memzero_explicit(snp_dev->vmpck, VMPCK_KEY_LEN); snp_dev->vmpck = NULL; @@ -291,44 +291,45 @@ static int dec_payload(struct snp_guest_dev *snp_dev, struct snp_guest_msg *msg, static int verify_and_dec_payload(struct snp_guest_dev *snp_dev, void *payload, u32 sz) { struct snp_guest_crypto *crypto = snp_dev->crypto; - struct snp_guest_msg *resp = &snp_dev->secret_response; - struct snp_guest_msg *req = &snp_dev->secret_request; - struct snp_guest_msg_hdr *req_hdr = &req->hdr; - struct snp_guest_msg_hdr *resp_hdr = &resp->hdr; + struct snp_guest_msg *resp_msg = &snp_dev->secret_response; + struct snp_guest_msg *req_msg = &snp_dev->secret_request; + struct snp_guest_msg_hdr *req_msg_hdr = &req_msg->hdr; + struct snp_guest_msg_hdr *resp_msg_hdr = &resp_msg->hdr; - dev_dbg(snp_dev->dev, "response [seqno %lld type %d version %d sz %d]\n", - resp_hdr->msg_seqno, resp_hdr->msg_type, resp_hdr->msg_version, resp_hdr->msg_sz); + pr_debug("response [seqno %lld type %d version %d sz %d]\n", + resp_msg_hdr->msg_seqno, resp_msg_hdr->msg_type, resp_msg_hdr->msg_version, + resp_msg_hdr->msg_sz); /* Copy response from shared memory to encrypted memory. */ - memcpy(resp, snp_dev->response, sizeof(*resp)); + memcpy(resp_msg, snp_dev->response, sizeof(*resp_msg)); /* Verify that the sequence counter is incremented by 1 */ - if (unlikely(resp_hdr->msg_seqno != (req_hdr->msg_seqno + 1))) + if (unlikely(resp_msg_hdr->msg_seqno != (req_msg_hdr->msg_seqno + 1))) return -EBADMSG; /* Verify response message type and version number. */ - if (resp_hdr->msg_type != (req_hdr->msg_type + 1) || - resp_hdr->msg_version != req_hdr->msg_version) + if (resp_msg_hdr->msg_type != (req_msg_hdr->msg_type + 1) || + resp_msg_hdr->msg_version != req_msg_hdr->msg_version) return -EBADMSG; /* * If the message size is greater than our buffer length then return * an error. */ - if (unlikely((resp_hdr->msg_sz + crypto->a_len) > sz)) + if (unlikely((resp_msg_hdr->msg_sz + crypto->a_len) > sz)) return -EBADMSG; /* Decrypt the payload */ - return dec_payload(snp_dev, resp, payload, resp_hdr->msg_sz + crypto->a_len); + return dec_payload(snp_dev, resp_msg, payload, resp_msg_hdr->msg_sz + crypto->a_len); } static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8 type, void *payload, size_t sz) { - struct snp_guest_msg *req = &snp_dev->secret_request; - struct snp_guest_msg_hdr *hdr = &req->hdr; + struct snp_guest_msg *msg = &snp_dev->secret_request; + struct snp_guest_msg_hdr *hdr = &msg->hdr; - memset(req, 0, sizeof(*req)); + memset(msg, 0, sizeof(*msg)); hdr->algo = SNP_AEAD_AES_256_GCM; hdr->hdr_version = MSG_HDR_VER; @@ -343,10 +344,10 @@ static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8 if (!hdr->msg_seqno) return -ENOSR; - dev_dbg(snp_dev->dev, "request [seqno %lld type %d version %d sz %d]\n", - hdr->msg_seqno, hdr->msg_type, hdr->msg_version, hdr->msg_sz); + pr_debug("request [seqno %lld type %d version %d sz %d]\n", + hdr->msg_seqno, hdr->msg_type, hdr->msg_version, hdr->msg_sz); - return __enc_payload(snp_dev, req, payload, sz); + return __enc_payload(snp_dev, msg, payload, sz); } static int __handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, @@ -495,8 +496,8 @@ struct snp_req_resp { static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg) { struct snp_guest_crypto *crypto = snp_dev->crypto; - struct snp_report_req *req = &snp_dev->req.report; - struct snp_report_resp *resp; + struct snp_report_req *report_req = &snp_dev->req.report; + struct snp_report_resp *report_resp; int rc, resp_len; lockdep_assert_held(&snp_cmd_mutex); @@ -504,7 +505,7 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io if (!arg->req_data || !arg->resp_data) return -EINVAL; - if (copy_from_user(req, (void __user *)arg->req_data, sizeof(*req))) + if (copy_from_user(report_req, (void __user *)arg->req_data, sizeof(*report_req))) return -EFAULT; /* @@ -512,30 +513,29 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io * response payload. Make sure that it has enough space to cover the * authtag. */ - resp_len = sizeof(resp->data) + crypto->a_len; - resp = kzalloc(resp_len, GFP_KERNEL_ACCOUNT); - if (!resp) + resp_len = sizeof(report_resp->data) + crypto->a_len; + report_resp = kzalloc(resp_len, GFP_KERNEL_ACCOUNT); + if (!report_resp) return -ENOMEM; - rc = handle_guest_request(snp_dev, SVM_VMGEXIT_GUEST_REQUEST, arg, - SNP_MSG_REPORT_REQ, req, sizeof(*req), resp->data, - resp_len); + rc = handle_guest_request(snp_dev, SVM_VMGEXIT_GUEST_REQUEST, arg, SNP_MSG_REPORT_REQ, + report_req, sizeof(*report_req), report_resp->data, resp_len); if (rc) goto e_free; - if (copy_to_user((void __user *)arg->resp_data, resp, sizeof(*resp))) + if (copy_to_user((void __user *)arg->resp_data, report_resp, sizeof(*report_resp))) rc = -EFAULT; e_free: - kfree(resp); + kfree(report_resp); return rc; } static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg) { - struct snp_derived_key_req *req = &snp_dev->req.derived_key; + struct snp_derived_key_req *derived_key_req = &snp_dev->req.derived_key; struct snp_guest_crypto *crypto = snp_dev->crypto; - struct snp_derived_key_resp resp = {0}; + struct snp_derived_key_resp derived_key_resp = {0}; int rc, resp_len; /* Response data is 64 bytes and max authsize for GCM is 16 bytes. */ u8 buf[64 + 16]; @@ -550,25 +550,27 @@ static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_reque * response payload. Make sure that it has enough space to cover the * authtag. */ - resp_len = sizeof(resp.data) + crypto->a_len; + resp_len = sizeof(derived_key_resp.data) + crypto->a_len; if (sizeof(buf) < resp_len) return -ENOMEM; - if (copy_from_user(req, (void __user *)arg->req_data, sizeof(*req))) + if (copy_from_user(derived_key_req, (void __user *)arg->req_data, + sizeof(*derived_key_req))) return -EFAULT; - rc = handle_guest_request(snp_dev, SVM_VMGEXIT_GUEST_REQUEST, arg, - SNP_MSG_KEY_REQ, req, sizeof(*req), buf, resp_len); + rc = handle_guest_request(snp_dev, SVM_VMGEXIT_GUEST_REQUEST, arg, SNP_MSG_KEY_REQ, + derived_key_req, sizeof(*derived_key_req), buf, resp_len); if (rc) return rc; - memcpy(resp.data, buf, sizeof(resp.data)); - if (copy_to_user((void __user *)arg->resp_data, &resp, sizeof(resp))) + memcpy(derived_key_resp.data, buf, sizeof(derived_key_resp.data)); + if (copy_to_user((void __user *)arg->resp_data, &derived_key_resp, + sizeof(derived_key_resp))) rc = -EFAULT; /* The response buffer contains the sensitive data, explicitly clear it. */ memzero_explicit(buf, sizeof(buf)); - memzero_explicit(&resp, sizeof(resp)); + memzero_explicit(&derived_key_resp, sizeof(derived_key_resp)); return rc; } @@ -576,9 +578,9 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques struct snp_req_resp *io) { - struct snp_ext_report_req *req = &snp_dev->req.ext_report; + struct snp_ext_report_req *report_req = &snp_dev->req.ext_report; struct snp_guest_crypto *crypto = snp_dev->crypto; - struct snp_report_resp *resp; + struct snp_report_resp *report_resp; int ret, npages = 0, resp_len; sockptr_t certs_address; @@ -587,22 +589,22 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques if (sockptr_is_null(io->req_data) || sockptr_is_null(io->resp_data)) return -EINVAL; - if (copy_from_sockptr(req, io->req_data, sizeof(*req))) + if (copy_from_sockptr(report_req, io->req_data, sizeof(*report_req))) return -EFAULT; /* caller does not want certificate data */ - if (!req->certs_len || !req->certs_address) + if (!report_req->certs_len || !report_req->certs_address) goto cmd; - if (req->certs_len > SEV_FW_BLOB_MAX_SIZE || - !IS_ALIGNED(req->certs_len, PAGE_SIZE)) + if (report_req->certs_len > SEV_FW_BLOB_MAX_SIZE || + !IS_ALIGNED(report_req->certs_len, PAGE_SIZE)) return -EINVAL; if (sockptr_is_kernel(io->resp_data)) { - certs_address = KERNEL_SOCKPTR((void *)req->certs_address); + certs_address = KERNEL_SOCKPTR((void *)report_req->certs_address); } else { - certs_address = USER_SOCKPTR((void __user *)req->certs_address); - if (!access_ok(certs_address.user, req->certs_len)) + certs_address = USER_SOCKPTR((void __user *)report_req->certs_address); + if (!access_ok(certs_address.user, report_req->certs_len)) return -EFAULT; } @@ -612,45 +614,45 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques * the host. If host does not supply any certs in it, then copy * zeros to indicate that certificate data was not provided. */ - memset(snp_dev->certs_data, 0, req->certs_len); - npages = req->certs_len >> PAGE_SHIFT; + memset(snp_dev->certs_data, 0, report_req->certs_len); + npages = report_req->certs_len >> PAGE_SHIFT; cmd: /* * The intermediate response buffer is used while decrypting the * response payload. Make sure that it has enough space to cover the * authtag. */ - resp_len = sizeof(resp->data) + crypto->a_len; - resp = kzalloc(resp_len, GFP_KERNEL_ACCOUNT); - if (!resp) + resp_len = sizeof(report_resp->data) + crypto->a_len; + report_resp = kzalloc(resp_len, GFP_KERNEL_ACCOUNT); + if (!report_resp) return -ENOMEM; snp_dev->input.data_npages = npages; - ret = handle_guest_request(snp_dev, SVM_VMGEXIT_EXT_GUEST_REQUEST, arg, - SNP_MSG_REPORT_REQ, &req->data, - sizeof(req->data), resp->data, resp_len); + ret = handle_guest_request(snp_dev, SVM_VMGEXIT_EXT_GUEST_REQUEST, arg, SNP_MSG_REPORT_REQ, + &report_req->data, sizeof(report_req->data), + report_resp->data, resp_len); /* If certs length is invalid then copy the returned length */ if (arg->vmm_error == SNP_GUEST_VMM_ERR_INVALID_LEN) { - req->certs_len = snp_dev->input.data_npages << PAGE_SHIFT; + report_req->certs_len = snp_dev->input.data_npages << PAGE_SHIFT; - if (copy_to_sockptr(io->req_data, req, sizeof(*req))) + if (copy_to_sockptr(io->req_data, report_req, sizeof(*report_req))) ret = -EFAULT; } if (ret) goto e_free; - if (npages && copy_to_sockptr(certs_address, snp_dev->certs_data, req->certs_len)) { + if (npages && copy_to_sockptr(certs_address, snp_dev->certs_data, report_req->certs_len)) { ret = -EFAULT; goto e_free; } - if (copy_to_sockptr(io->resp_data, resp, sizeof(*resp))) + if (copy_to_sockptr(io->resp_data, report_resp, sizeof(*report_resp))) ret = -EFAULT; e_free: - kfree(resp); + kfree(report_resp); return ret; } @@ -1090,6 +1092,8 @@ static int __init sev_guest_probe(struct platform_device *pdev) void __iomem *mapping; int ret; + BUILD_BUG_ON(sizeof(struct snp_guest_msg) > PAGE_SIZE); + if (!cc_platform_has(CC_ATTR_GUEST_SEV_SNP)) return -ENODEV; @@ -1115,13 +1119,13 @@ static int __init sev_guest_probe(struct platform_device *pdev) ret = -EINVAL; snp_dev->vmpck = get_vmpck(vmpck_id, secrets, &snp_dev->os_area_msg_seqno); if (!snp_dev->vmpck) { - dev_err(dev, "invalid vmpck id %d\n", vmpck_id); + dev_err(dev, "Invalid VMPCK%d communication key\n", vmpck_id); goto e_unmap; } /* Verify that VMPCK is not zero. */ if (is_vmpck_empty(snp_dev)) { - dev_err(dev, "vmpck id %d is null\n", vmpck_id); + dev_err(dev, "Empty VMPCK%d communication key\n", vmpck_id); goto e_unmap; } @@ -1172,7 +1176,7 @@ static int __init sev_guest_probe(struct platform_device *pdev) if (ret) goto e_free_cert_data; - dev_info(dev, "Initialized SEV guest driver (using vmpck_id %d)\n", vmpck_id); + dev_info(dev, "Initialized SEV guest driver (using VMPCK%d communication key)\n", vmpck_id); return 0; e_free_cert_data: |