Add wrappers for Intel(R) SGX ENCLS opcode leaf functions except ENCLS(EINIT). ENCLS invokes privileged functions for managing (creation, initialization and swapping) and debugging enclaves.
Signed-off-by: Jarkko Sakkinen <[email protected]> Co-developed-by: Sean Christopherson <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> --- arch/x86/include/asm/sgx.h | 244 +++++++++++++++++++++++++++++++++++++ 1 file changed, 244 insertions(+) diff --git a/arch/x86/include/asm/sgx.h b/arch/x86/include/asm/sgx.h index f4f82f0453a9..e66e2572011e 100644 --- a/arch/x86/include/asm/sgx.h +++ b/arch/x86/include/asm/sgx.h @@ -10,4 +10,248 @@ extern bool sgx_enabled; extern bool sgx_lc_enabled; +/** + * ENCLS_FAULT_FLAG - flag signifying an ENCLS return code is a trapnr + * + * ENCLS has its own (positive value) error codes and also generates + * ENCLS specific #GP and #PF faults. And the ENCLS values get munged + * with system error codes as everything percolates back up the stack. + * Unfortunately (for us), we need to precisely identify each unique + * error code, e.g. the action taken if EWB fails varies based on the + * type of fault and on the exact SGX error code, i.e. we can't simply + * convert all faults to -EFAULT. + * + * To make all three error types coexist, we set bit 30 to identify an + * ENCLS fault. Bit 31 (technically bits N:31) is used to differentiate + * between positive (faults and SGX error codes) and negative (system + * error codes) values. + */ +#define ENCLS_FAULT_FLAG 0x40000000 + +/** + * Check for a fault by looking for a postive value with the fault + * flag set. The postive value check is needed to filter out system + * error codes since negative values will have all higher order bits + * set, including ENCLS_FAULT_FLAG. + */ +#define IS_ENCLS_FAULT(r) ((int)(r) > 0 && ((r) & ENCLS_FAULT_FLAG)) + +/** + * Retrieve the encoded trapnr from the specified return code. + */ +#define ENCLS_TRAPNR(r) ((r) & ~ENCLS_FAULT_FLAG) + +/** + * encls_to_err - translate an ENCLS fault or SGX code into a system error code + * @ret: positive value return code + * + * Translate a postive return code, e.g. from ENCLS, into a system error + * code. Primarily used by functions that cannot return a non-negative + * error code, e.g. kernel callbacks. + * + * Return: + * 0 on success, + * -errno on failure + */ +static inline int encls_to_err(int ret) +{ + if (IS_ENCLS_FAULT(ret)) + return -EFAULT; + + switch (ret) { + case SGX_UNMASKED_EVENT: + return -EINTR; + case SGX_INVALID_SIG_STRUCT: + case SGX_INVALID_ATTRIBUTE: + case SGX_INVALID_MEASUREMENT: + case SGX_INVALID_EINITTOKEN: + case SGX_INVALID_CPUSVN: + case SGX_INVALID_ISVSVN: + case SGX_INVALID_KEYNAME: + return -EINVAL; + case SGX_ENCLAVE_ACT: + case SGX_CHILD_PRESENT: + case SGX_ENTRYEPOCH_LOCKED: + case SGX_PREV_TRK_INCMPL: + case SGX_PAGE_NOT_MODIFIABLE: + case SGX_PAGE_NOT_DEBUGGABLE: + return -EBUSY; + default: + return -EIO; + }; +} + +/** + * __encls_ret_N - encode an ENCLS leaf that returns an error code in EAX + * @rax: leaf number + * @inputs: asm inputs for the leaf + * + * Emit assembly for an ENCLS leaf that returns an error code, e.g. EREMOVE. + * And because SGX isn't complex enough as it is, leafs that return an error + * code also modify flags. + * + * Return: + * 0 on success, + * SGX error code on failure + */ +#define __encls_ret_N(rax, inputs...) \ + ({ \ + int ret; \ + asm volatile( \ + "1: .byte 0x0f, 0x01, 0xcf;\n\t" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3: orl $"__stringify(ENCLS_FAULT_FLAG)",%%eax\n" \ + " jmp 2b\n" \ + ".previous\n" \ + _ASM_EXTABLE_FAULT(1b, 3b) \ + : "=a"(ret) \ + : "a"(rax), inputs \ + : "memory", "cc"); \ + ret; \ + }) + +#define __encls_ret_1(rax, rcx) \ + ({ \ + __encls_ret_N(rax, "c"(rcx)); \ + }) + +#define __encls_ret_2(rax, rbx, rcx) \ + ({ \ + __encls_ret_N(rax, "b"(rbx), "c"(rcx)); \ + }) + +#define __encls_ret_3(rax, rbx, rcx, rdx) \ + ({ \ + __encls_ret_N(rax, "b"(rbx), "c"(rcx), "d"(rdx)); \ + }) + +/** + * __encls_N - encode an ENCLS leaf that doesn't return an error code + * @rax: leaf number + * @rbx_out: optional output variable + * @inputs: asm inputs for the leaf + * + * Emit assembly for an ENCLS leaf that does not return an error code, + * e.g. ECREATE. Leaves without error codes either succeed or fault. + * @rbx_out is an optional parameter for use by EDGBRD, which returns + * the the requested value in RBX. + * + * Return: + * 0 on success, + * trapnr with ENCLS_FAULT_FLAG set on fault + */ +#define __encls_N(rax, rbx_out, inputs...) \ + ({ \ + int ret; \ + asm volatile( \ + "1: .byte 0x0f, 0x01, 0xcf;\n\t" \ + " xor %%eax,%%eax;\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3: orl $"__stringify(ENCLS_FAULT_FLAG)",%%eax\n" \ + " jmp 2b\n" \ + ".previous\n" \ + _ASM_EXTABLE_FAULT(1b, 3b) \ + : "=a"(ret), "=b"(rbx_out) \ + : "a"(rax), inputs \ + : "memory"); \ + ret; \ + }) + +#define __encls_2(rax, rbx, rcx) \ + ({ \ + unsigned long ign_rbx_out; \ + __encls_N(rax, ign_rbx_out, "b"(rbx), "c"(rcx)); \ + }) + +#define __encls_1_1(rax, data, rcx) \ + ({ \ + unsigned long rbx_out; \ + int ret = __encls_N(rax, rbx_out, "c"(rcx)); \ + if (!ret) \ + data = rbx_out; \ + ret; \ + }) + +static inline int __ecreate(struct sgx_pageinfo *pginfo, void __iomem *secs) +{ + return __encls_2(SGX_ECREATE, pginfo, secs); +} + +static inline int __eextend(void __iomem *secs, void __iomem *addr) +{ + return __encls_2(SGX_EEXTEND, secs, addr); +} + +static inline int __eadd(struct sgx_pageinfo *pginfo, void __iomem *addr) +{ + return __encls_2(SGX_EADD, pginfo, addr); +} + +static inline int __einit(void *sigstruct, struct sgx_einittoken *einittoken, + void __iomem *secs) +{ + return __encls_ret_3(SGX_EINIT, sigstruct, secs, einittoken); +} + +static inline int __eremove(void __iomem *addr) +{ + return __encls_ret_1(SGX_EREMOVE, addr); +} + +static inline int __edbgwr(void __iomem *addr, unsigned long *data) +{ + return __encls_2(SGX_EDGBWR, *data, addr); +} + +static inline int __edbgrd(void __iomem *addr, unsigned long *data) +{ + return __encls_1_1(SGX_EDGBRD, *data, addr); +} + +static inline int __etrack(void __iomem *addr) +{ + return __encls_ret_1(SGX_ETRACK, addr); +} + +static inline int __eldu(struct sgx_pageinfo *pginfo, void __iomem *addr, + void *va) +{ + return __encls_ret_3(SGX_ELDU, pginfo, addr, va); +} + +static inline int __eblock(void __iomem *addr) +{ + return __encls_ret_1(SGX_EBLOCK, addr); +} + +static inline int __epa(void __iomem *addr) +{ + unsigned long rbx = SGX_PAGE_TYPE_VA; + + return __encls_2(SGX_EPA, rbx, addr); +} + +static inline int __ewb(struct sgx_pageinfo *pginfo, void __iomem *addr, + void __iomem *va) +{ + return __encls_ret_3(SGX_EWB, pginfo, addr, va); +} + +static inline int __eaug(struct sgx_pageinfo *pginfo, void __iomem *addr) +{ + return __encls_2(SGX_EAUG, pginfo, addr); +} + +static inline int __emodpr(struct sgx_secinfo *secinfo, void __iomem *addr) +{ + return __encls_ret_2(SGX_EMODPR, secinfo, addr); +} + +static inline int __emodt(struct sgx_secinfo *secinfo, void __iomem *addr) +{ + return __encls_ret_2(SGX_EMODT, secinfo, addr); +} + #endif /* _ASM_X86_SGX_H */ -- 2.17.1
