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1// SPDX-License-Identifier: GPL-2.02/* Copyright(c) 2016-20 Intel Corporation. */3 4#include <stddef.h>5#include "defines.h"6 7/*8 * Data buffer spanning two pages that will be placed first in the .data9 * segment via the linker script. Even if not used internally the second page10 * is needed by external test manipulating page permissions, so mark11 * encl_buffer as "used" to make sure it is entirely preserved by the compiler.12 */13static uint8_t __used __section(".data.encl_buffer") encl_buffer[8192] = { 1 };14 15enum sgx_enclu_function {16 EACCEPT = 0x5,17 EMODPE = 0x6,18};19 20static void do_encl_emodpe(void *_op)21{22 struct sgx_secinfo secinfo __aligned(sizeof(struct sgx_secinfo)) = {0};23 struct encl_op_emodpe *op = _op;24 25 secinfo.flags = op->flags;26 27 asm volatile(".byte 0x0f, 0x01, 0xd7"28 : /* no outputs */29 : "a" (EMODPE),30 "b" (&secinfo),31 "c" (op->epc_addr)32 : "memory" /* read from secinfo pointer */);33}34 35static void do_encl_eaccept(void *_op)36{37 struct sgx_secinfo secinfo __aligned(sizeof(struct sgx_secinfo)) = {0};38 struct encl_op_eaccept *op = _op;39 int rax;40 41 secinfo.flags = op->flags;42 43 asm volatile(".byte 0x0f, 0x01, 0xd7"44 : "=a" (rax)45 : "a" (EACCEPT),46 "b" (&secinfo),47 "c" (op->epc_addr)48 : "memory" /* read from secinfo pointer */);49 50 op->ret = rax;51}52 53static void *memcpy(void *dest, const void *src, size_t n)54{55 size_t i;56 57 for (i = 0; i < n; i++)58 ((char *)dest)[i] = ((char *)src)[i];59 60 return dest;61}62 63static void *memset(void *dest, int c, size_t n)64{65 size_t i;66 67 for (i = 0; i < n; i++)68 ((char *)dest)[i] = c;69 70 return dest;71}72 73static void do_encl_init_tcs_page(void *_op)74{75 struct encl_op_init_tcs_page *op = _op;76 void *tcs = (void *)op->tcs_page;77 uint32_t val_32;78 79 memset(tcs, 0, 16); /* STATE and FLAGS */80 memcpy(tcs + 16, &op->ssa, 8); /* OSSA */81 memset(tcs + 24, 0, 4); /* CSSA */82 val_32 = 1;83 memcpy(tcs + 28, &val_32, 4); /* NSSA */84 memcpy(tcs + 32, &op->entry, 8); /* OENTRY */85 memset(tcs + 40, 0, 24); /* AEP, OFSBASE, OGSBASE */86 val_32 = 0xFFFFFFFF;87 memcpy(tcs + 64, &val_32, 4); /* FSLIMIT */88 memcpy(tcs + 68, &val_32, 4); /* GSLIMIT */89 memset(tcs + 72, 0, 4024); /* Reserved */90}91 92static void do_encl_op_put_to_buf(void *op)93{94 struct encl_op_put_to_buf *op2 = op;95 96 memcpy(&encl_buffer[0], &op2->value, 8);97}98 99static void do_encl_op_get_from_buf(void *op)100{101 struct encl_op_get_from_buf *op2 = op;102 103 memcpy(&op2->value, &encl_buffer[0], 8);104}105 106static void do_encl_op_put_to_addr(void *_op)107{108 struct encl_op_put_to_addr *op = _op;109 110 memcpy((void *)op->addr, &op->value, 8);111}112 113static void do_encl_op_get_from_addr(void *_op)114{115 struct encl_op_get_from_addr *op = _op;116 117 memcpy(&op->value, (void *)op->addr, 8);118}119 120static void do_encl_op_nop(void *_op)121{122 123}124 125/*126 * Symbol placed at the start of the enclave image by the linker script.127 * Declare this extern symbol with visibility "hidden" to ensure the compiler128 * does not access it through the GOT and generates position-independent129 * addressing as __encl_base(%rip), so we can get the actual enclave base130 * during runtime.131 */132extern const uint8_t __attribute__((visibility("hidden"))) __encl_base;133 134typedef void (*encl_op_t)(void *);135static const encl_op_t encl_op_array[ENCL_OP_MAX] = {136 do_encl_op_put_to_buf,137 do_encl_op_get_from_buf,138 do_encl_op_put_to_addr,139 do_encl_op_get_from_addr,140 do_encl_op_nop,141 do_encl_eaccept,142 do_encl_emodpe,143 do_encl_init_tcs_page,144};145 146void encl_body(void *rdi, void *rsi)147{148 struct encl_op_header *header = (struct encl_op_header *)rdi;149 encl_op_t op;150 151 if (header->type >= ENCL_OP_MAX)152 return;153 154 /*155 * The enclave base address needs to be added, as this call site156 * *cannot be* made rip-relative by the compiler, or fixed up by157 * any other possible means.158 */159 op = ((uint64_t)&__encl_base) + encl_op_array[header->type];160 161 (*op)(header);162}163