Add a snp_guest_req structure to simplify the function arguments. The structure will be used to call the SNP Guest message request API instead of passing a long list of parameters. Update snp_issue_guest_request() prototype to include the new guest request structure and move the prototype to sev_guest.h. Signed-off-by: Nikunj A Dadhania <nikunj@xxxxxxx> Tested-by: Peter Gonda <pgonda@xxxxxxxxxx> --- .../x86/include/asm}/sev-guest.h | 18 +++ arch/x86/include/asm/sev.h | 8 -- arch/x86/kernel/sev.c | 15 ++- drivers/virt/coco/sev-guest/sev-guest.c | 108 +++++++++++------- 4 files changed, 93 insertions(+), 56 deletions(-) rename {drivers/virt/coco/sev-guest => arch/x86/include/asm}/sev-guest.h (78%) diff --git a/drivers/virt/coco/sev-guest/sev-guest.h b/arch/x86/include/asm/sev-guest.h similarity index 78% rename from drivers/virt/coco/sev-guest/sev-guest.h rename to arch/x86/include/asm/sev-guest.h index ceb798a404d6..27cc15ad6131 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.h +++ b/arch/x86/include/asm/sev-guest.h @@ -63,4 +63,22 @@ struct snp_guest_msg { u8 payload[4000]; } __packed; +struct snp_guest_req { + void *req_buf; + size_t req_sz; + + void *resp_buf; + size_t resp_sz; + + void *data; + size_t data_npages; + + u64 exit_code; + unsigned int vmpck_id; + u8 msg_version; + u8 msg_type; +}; + +int snp_issue_guest_request(struct snp_guest_req *req, struct snp_req_data *input, + struct snp_guest_request_ioctl *rio); #endif /* __VIRT_SEVGUEST_H__ */ diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h index 5b4a1ce3d368..78465a8c7dc6 100644 --- a/arch/x86/include/asm/sev.h +++ b/arch/x86/include/asm/sev.h @@ -97,8 +97,6 @@ extern bool handle_vc_boot_ghcb(struct pt_regs *regs); struct snp_req_data { unsigned long req_gpa; unsigned long resp_gpa; - unsigned long data_gpa; - unsigned int data_npages; }; struct sev_guest_platform_data { @@ -209,7 +207,6 @@ void snp_set_memory_private(unsigned long vaddr, unsigned long npages); void snp_set_wakeup_secondary_cpu(void); bool snp_init(struct boot_params *bp); void __init __noreturn snp_abort(void); -int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio); void snp_accept_memory(phys_addr_t start, phys_addr_t end); u64 snp_get_unsupported_features(u64 status); u64 sev_get_status(void); @@ -233,11 +230,6 @@ static inline void snp_set_memory_private(unsigned long vaddr, unsigned long npa static inline void snp_set_wakeup_secondary_cpu(void) { } static inline bool snp_init(struct boot_params *bp) { return false; } static inline void snp_abort(void) { } -static inline int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio) -{ - return -ENOTTY; -} - static inline void snp_accept_memory(phys_addr_t start, phys_addr_t end) { } static inline u64 snp_get_unsupported_features(u64 status) { return 0; } static inline u64 sev_get_status(void) { return 0; } diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index c67285824e82..fd89aca22f6a 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -28,6 +28,7 @@ #include <asm/cpu_entry_area.h> #include <asm/stacktrace.h> #include <asm/sev.h> +#include <asm/sev-guest.h> #include <asm/insn-eval.h> #include <asm/fpu/xcr.h> #include <asm/processor.h> @@ -2170,15 +2171,21 @@ static int __init init_sev_config(char *str) } __setup("sev=", init_sev_config); -int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio) +int snp_issue_guest_request(struct snp_guest_req *req, struct snp_req_data *input, + struct snp_guest_request_ioctl *rio) { struct ghcb_state state; struct es_em_ctxt ctxt; unsigned long flags; struct ghcb *ghcb; + u64 exit_code; int ret; rio->exitinfo2 = SEV_RET_NO_FW_CALL; + if (!req) + return -EINVAL; + + exit_code = req->exit_code; /* * __sev_get_ghcb() needs to run with IRQs disabled because it is using @@ -2195,8 +2202,8 @@ int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct sn vc_ghcb_invalidate(ghcb); if (exit_code == SVM_VMGEXIT_EXT_GUEST_REQUEST) { - ghcb_set_rax(ghcb, input->data_gpa); - ghcb_set_rbx(ghcb, input->data_npages); + ghcb_set_rax(ghcb, __pa(req->data)); + ghcb_set_rbx(ghcb, req->data_npages); } ret = sev_es_ghcb_hv_call(ghcb, &ctxt, exit_code, input->req_gpa, input->resp_gpa); @@ -2215,7 +2222,7 @@ int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct sn case SNP_GUEST_VMM_ERR(SNP_GUEST_VMM_ERR_INVALID_LEN): /* Number of expected pages are returned in RBX */ if (exit_code == SVM_VMGEXIT_EXT_GUEST_REQUEST) { - input->data_npages = ghcb_get_rbx(ghcb); + req->data_npages = ghcb_get_rbx(ghcb); ret = -ENOSPC; break; } diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c index 469e10d9bf35..5cafbd1c42cb 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.c +++ b/drivers/virt/coco/sev-guest/sev-guest.c @@ -27,8 +27,7 @@ #include <asm/svm.h> #include <asm/sev.h> - -#include "sev-guest.h" +#include <asm/sev-guest.h> #define DEVICE_NAME "sev-guest" @@ -169,7 +168,7 @@ static struct aesgcm_ctx *snp_init_crypto(u8 *key, size_t keylen) return ctx; } -static int verify_and_dec_payload(struct snp_guest_dev *snp_dev, void *payload, u32 sz) +static int verify_and_dec_payload(struct snp_guest_dev *snp_dev, struct snp_guest_req *guest_req) { struct snp_guest_msg *resp = &snp_dev->secret_response; struct snp_guest_msg *req = &snp_dev->secret_request; @@ -198,36 +197,35 @@ static int verify_and_dec_payload(struct snp_guest_dev *snp_dev, void *payload, * If the message size is greater than our buffer length then return * an error. */ - if (unlikely((resp_hdr->msg_sz + ctx->authsize) > sz)) + if (unlikely((resp_hdr->msg_sz + ctx->authsize) > guest_req->resp_sz)) return -EBADMSG; /* Decrypt the payload */ memcpy(iv, &resp_hdr->msg_seqno, sizeof(resp_hdr->msg_seqno)); - if (!aesgcm_decrypt(ctx, payload, resp->payload, resp_hdr->msg_sz, + if (!aesgcm_decrypt(ctx, guest_req->resp_buf, resp->payload, resp_hdr->msg_sz, &resp_hdr->algo, AAD_LEN, iv, resp_hdr->authtag)) return -EBADMSG; return 0; } -static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8 type, - void *payload, size_t sz) +static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, struct snp_guest_req *req) { - 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; struct aesgcm_ctx *ctx = snp_dev->ctx; u8 iv[GCM_AES_IV_SIZE] = {}; - memset(req, 0, sizeof(*req)); + memset(msg, 0, sizeof(*msg)); hdr->algo = SNP_AEAD_AES_256_GCM; hdr->hdr_version = MSG_HDR_VER; hdr->hdr_sz = sizeof(*hdr); - hdr->msg_type = type; - hdr->msg_version = version; + hdr->msg_type = req->msg_type; + hdr->msg_version = req->msg_version; hdr->msg_seqno = seqno; - hdr->msg_vmpck = vmpck_id; - hdr->msg_sz = sz; + hdr->msg_vmpck = req->vmpck_id; + hdr->msg_sz = req->req_sz; /* Verify the sequence number is non-zero */ if (!hdr->msg_seqno) @@ -236,17 +234,17 @@ static int enc_payload(struct snp_guest_dev *snp_dev, u64 seqno, int version, u8 pr_debug("request [seqno %lld type %d version %d sz %d]\n", hdr->msg_seqno, hdr->msg_type, hdr->msg_version, hdr->msg_sz); - if (WARN_ON((sz + ctx->authsize) > sizeof(req->payload))) + if (WARN_ON((req->req_sz + ctx->authsize) > sizeof(msg->payload))) return -EBADMSG; memcpy(iv, &hdr->msg_seqno, sizeof(hdr->msg_seqno)); - aesgcm_encrypt(ctx, req->payload, payload, sz, &hdr->algo, AAD_LEN, - iv, hdr->authtag); + aesgcm_encrypt(ctx, msg->payload, req->req_buf, req->req_sz, &hdr->algo, + AAD_LEN, iv, hdr->authtag); return 0; } -static int __handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, +static int __handle_guest_request(struct snp_guest_dev *snp_dev, struct snp_guest_req *req, struct snp_guest_request_ioctl *rio) { unsigned long req_start = jiffies; @@ -261,7 +259,7 @@ static int __handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, * sequence number must be incremented or the VMPCK must be deleted to * prevent reuse of the IV. */ - rc = snp_issue_guest_request(exit_code, &snp_dev->input, rio); + rc = snp_issue_guest_request(req, &snp_dev->input, rio); switch (rc) { case -ENOSPC: /* @@ -271,8 +269,8 @@ static int __handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, * order to increment the sequence number and thus avoid * IV reuse. */ - override_npages = snp_dev->input.data_npages; - exit_code = SVM_VMGEXIT_GUEST_REQUEST; + override_npages = req->data_npages; + req->exit_code = SVM_VMGEXIT_GUEST_REQUEST; /* * Override the error to inform callers the given extended @@ -327,15 +325,13 @@ static int __handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, } if (override_npages) - snp_dev->input.data_npages = override_npages; + req->data_npages = override_npages; return rc; } -static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, - struct snp_guest_request_ioctl *rio, u8 type, - void *req_buf, size_t req_sz, void *resp_buf, - u32 resp_sz) +static int snp_send_guest_request(struct snp_guest_dev *snp_dev, struct snp_guest_req *req, + struct snp_guest_request_ioctl *rio) { u64 seqno; int rc; @@ -349,7 +345,7 @@ static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, memset(snp_dev->response, 0, sizeof(struct snp_guest_msg)); /* Encrypt the userspace provided payload in snp_dev->secret_request. */ - rc = enc_payload(snp_dev, seqno, rio->msg_version, type, req_buf, req_sz); + rc = enc_payload(snp_dev, seqno, req); if (rc) return rc; @@ -360,7 +356,7 @@ static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, memcpy(snp_dev->request, &snp_dev->secret_request, sizeof(snp_dev->secret_request)); - rc = __handle_guest_request(snp_dev, exit_code, rio); + rc = __handle_guest_request(snp_dev, req, rio); if (rc) { if (rc == -EIO && rio->exitinfo2 == SNP_GUEST_VMM_ERR(SNP_GUEST_VMM_ERR_INVALID_LEN)) @@ -369,12 +365,11 @@ static int handle_guest_request(struct snp_guest_dev *snp_dev, u64 exit_code, dev_alert(snp_dev->dev, "Detected error from ASP request. rc: %d, exitinfo2: 0x%llx\n", rc, rio->exitinfo2); - snp_disable_vmpck(snp_dev); return rc; } - rc = verify_and_dec_payload(snp_dev, resp_buf, resp_sz); + rc = verify_and_dec_payload(snp_dev, req); if (rc) { dev_alert(snp_dev->dev, "Detected unexpected decode failure from ASP. rc: %d\n", rc); snp_disable_vmpck(snp_dev); @@ -392,6 +387,7 @@ struct snp_req_resp { static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_ioctl *arg) { struct snp_report_req *req = &snp_dev->req.report; + struct snp_guest_req guest_req = {0}; struct snp_report_resp *resp; int rc, resp_len; @@ -413,9 +409,16 @@ static int get_report(struct snp_guest_dev *snp_dev, struct snp_guest_request_io if (!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); + guest_req.msg_version = arg->msg_version; + guest_req.msg_type = SNP_MSG_REPORT_REQ; + guest_req.vmpck_id = vmpck_id; + guest_req.req_buf = req; + guest_req.req_sz = sizeof(*req); + guest_req.resp_buf = resp->data; + guest_req.resp_sz = resp_len; + guest_req.exit_code = SVM_VMGEXIT_GUEST_REQUEST; + + rc = snp_send_guest_request(snp_dev, &guest_req, arg); if (rc) goto e_free; @@ -431,6 +434,7 @@ static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_reque { struct snp_derived_key_req *req = &snp_dev->req.derived_key; struct snp_derived_key_resp resp = {0}; + struct snp_guest_req guest_req = {0}; int rc, resp_len; /* Response data is 64 bytes and max authsize for GCM is 16 bytes. */ u8 buf[64 + 16]; @@ -452,8 +456,16 @@ static int get_derived_key(struct snp_guest_dev *snp_dev, struct snp_guest_reque if (copy_from_user(req, (void __user *)arg->req_data, sizeof(*req))) return -EFAULT; - rc = handle_guest_request(snp_dev, SVM_VMGEXIT_GUEST_REQUEST, arg, - SNP_MSG_KEY_REQ, req, sizeof(*req), buf, resp_len); + guest_req.msg_version = arg->msg_version; + guest_req.msg_type = SNP_MSG_KEY_REQ; + guest_req.vmpck_id = vmpck_id; + guest_req.req_buf = req; + guest_req.req_sz = sizeof(*req); + guest_req.resp_buf = buf; + guest_req.resp_sz = resp_len; + guest_req.exit_code = SVM_VMGEXIT_GUEST_REQUEST; + + rc = snp_send_guest_request(snp_dev, &guest_req, arg); if (rc) return rc; @@ -472,9 +484,10 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques { struct snp_ext_report_req *req = &snp_dev->req.ext_report; + struct snp_guest_req guest_req = {0}; struct snp_report_resp *resp; - int ret, npages = 0, resp_len; sockptr_t certs_address; + int ret, resp_len; lockdep_assert_held(&snp_cmd_mutex); @@ -507,7 +520,7 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques * zeros to indicate that certificate data was not provided. */ memset(snp_dev->certs_data, 0, req->certs_len); - npages = req->certs_len >> PAGE_SHIFT; + guest_req.data_npages = req->certs_len >> PAGE_SHIFT; cmd: /* * The intermediate response buffer is used while decrypting the @@ -519,14 +532,21 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques if (!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); + guest_req.msg_version = arg->msg_version; + guest_req.msg_type = SNP_MSG_REPORT_REQ; + guest_req.vmpck_id = vmpck_id; + guest_req.req_buf = &req->data; + guest_req.req_sz = sizeof(req->data); + guest_req.resp_buf = resp->data; + guest_req.resp_sz = resp_len; + guest_req.exit_code = SVM_VMGEXIT_EXT_GUEST_REQUEST; + guest_req.data = snp_dev->certs_data; + + ret = snp_send_guest_request(snp_dev, &guest_req, arg); /* 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; + req->certs_len = guest_req.data_npages << PAGE_SHIFT; if (copy_to_sockptr(io->req_data, req, sizeof(*req))) ret = -EFAULT; @@ -535,7 +555,8 @@ static int get_ext_report(struct snp_guest_dev *snp_dev, struct snp_guest_reques if (ret) goto e_free; - if (npages && copy_to_sockptr(certs_address, snp_dev->certs_data, req->certs_len)) { + if (guest_req.data_npages && req->certs_len && + copy_to_sockptr(certs_address, snp_dev->certs_data, req->certs_len)) { ret = -EFAULT; goto e_free; } @@ -868,7 +889,6 @@ static int __init sev_guest_probe(struct platform_device *pdev) /* initial the input address for guest request */ snp_dev->input.req_gpa = __pa(snp_dev->request); snp_dev->input.resp_gpa = __pa(snp_dev->response); - snp_dev->input.data_gpa = __pa(snp_dev->certs_data); ret = tsm_register(&sev_tsm_ops, snp_dev, &tsm_report_extra_type); if (ret) -- 2.34.1