1/* 2 * RISC-V translation routines for the Control-Flow Integrity Extension 3 * 4 * Copyright (c) 2024 Rivos Inc. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2 or later, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License along with 16 * this program. If not, see <http://www.gnu.org/licenses/>. 17 */ 18 19#define REQUIRE_ZICFISS(ctx) do { \ 20 if (!ctx->cfg_ptr->ext_zicfiss) { \ 21 return false; \ 22 } \ 23} while (0) 24 25static bool trans_sspopchk(DisasContext *ctx, arg_sspopchk *a) 26{ 27 if (!ctx->bcfi_enabled) { 28 return false; 29 } 30 31 TCGv addr = tcg_temp_new(); 32 TCGLabel *skip = gen_new_label(); 33 uint32_t tmp = (get_xl(ctx) == MXL_RV64) ? 8 : 4; 34 TCGv data = tcg_temp_new(); 35 tcg_gen_ld_tl(addr, tcg_env, offsetof(CPURISCVState, ssp)); 36 decode_save_opc(ctx, RISCV_UW2_ALWAYS_STORE_AMO); 37 tcg_gen_qemu_ld_tl(data, addr, SS_MMU_INDEX(ctx), 38 mxl_memop(ctx) | MO_ALIGN); 39 TCGv rs1 = get_gpr(ctx, a->rs1, EXT_NONE); 40 tcg_gen_brcond_tl(TCG_COND_EQ, data, rs1, skip); 41 tcg_gen_st_tl(tcg_constant_tl(RISCV_EXCP_SW_CHECK_BCFI_TVAL), 42 tcg_env, offsetof(CPURISCVState, sw_check_code)); 43 gen_update_pc(ctx, 0); 44 gen_helper_raise_exception(tcg_env, 45 tcg_constant_i32(RISCV_EXCP_SW_CHECK)); 46 gen_set_label(skip); 47 tcg_gen_addi_tl(addr, addr, tmp); 48 tcg_gen_st_tl(addr, tcg_env, offsetof(CPURISCVState, ssp)); 49 50 return true; 51} 52 53static bool trans_sspush(DisasContext *ctx, arg_sspush *a) 54{ 55 if (!ctx->bcfi_enabled) { 56 return false; 57 } 58 59 TCGv addr = tcg_temp_new(); 60 int tmp = (get_xl(ctx) == MXL_RV64) ? -8 : -4; 61 TCGv data = get_gpr(ctx, a->rs2, EXT_NONE); 62 decode_save_opc(ctx, RISCV_UW2_ALWAYS_STORE_AMO); 63 tcg_gen_ld_tl(addr, tcg_env, offsetof(CPURISCVState, ssp)); 64 tcg_gen_addi_tl(addr, addr, tmp); 65 tcg_gen_qemu_st_tl(data, addr, SS_MMU_INDEX(ctx), 66 mxl_memop(ctx) | MO_ALIGN); 67 tcg_gen_st_tl(addr, tcg_env, offsetof(CPURISCVState, ssp)); 68 69 return true; 70} 71 72static bool trans_ssrdp(DisasContext *ctx, arg_ssrdp *a) 73{ 74 if (!ctx->bcfi_enabled || a->rd == 0) { 75 return false; 76 } 77 78 TCGv dest = dest_gpr(ctx, a->rd); 79 tcg_gen_ld_tl(dest, tcg_env, offsetof(CPURISCVState, ssp)); 80 gen_set_gpr(ctx, a->rd, dest); 81 82 return true; 83} 84 85static bool trans_ssamoswap_w(DisasContext *ctx, arg_amoswap_w *a) 86{ 87 REQUIRE_A_OR_ZAAMO(ctx); 88 REQUIRE_ZICFISS(ctx); 89 if (ctx->priv == PRV_M) { 90 generate_exception(ctx, RISCV_EXCP_STORE_AMO_ACCESS_FAULT); 91 } 92 93 if (!ctx->bcfi_enabled) { 94#ifndef CONFIG_USER_ONLY 95 gen_helper_ssamoswap_disabled(tcg_env); 96#else 97 return false; 98#endif 99 } 100 101 TCGv dest = dest_gpr(ctx, a->rd); 102 TCGv src1, src2 = get_gpr(ctx, a->rs2, EXT_NONE); 103 104 decode_save_opc(ctx, RISCV_UW2_ALWAYS_STORE_AMO); 105 src1 = get_address(ctx, a->rs1, 0); 106 107 tcg_gen_atomic_xchg_tl(dest, src1, src2, SS_MMU_INDEX(ctx), 108 (MO_ALIGN | MO_TESL)); 109 gen_set_gpr(ctx, a->rd, dest); 110 return true; 111} 112 113static bool trans_ssamoswap_d(DisasContext *ctx, arg_amoswap_w *a) 114{ 115 REQUIRE_64BIT(ctx); 116 REQUIRE_A_OR_ZAAMO(ctx); 117 REQUIRE_ZICFISS(ctx); 118 if (ctx->priv == PRV_M) { 119 generate_exception(ctx, RISCV_EXCP_STORE_AMO_ACCESS_FAULT); 120 } 121 122 if (!ctx->bcfi_enabled) { 123#ifndef CONFIG_USER_ONLY 124 gen_helper_ssamoswap_disabled(tcg_env); 125#else 126 return false; 127#endif 128 } 129 130 TCGv dest = dest_gpr(ctx, a->rd); 131 TCGv src1, src2 = get_gpr(ctx, a->rs2, EXT_NONE); 132 133 decode_save_opc(ctx, RISCV_UW2_ALWAYS_STORE_AMO); 134 src1 = get_address(ctx, a->rs1, 0); 135 136 tcg_gen_atomic_xchg_tl(dest, src1, src2, SS_MMU_INDEX(ctx), 137 (MO_ALIGN | MO_TESQ)); 138 gen_set_gpr(ctx, a->rd, dest); 139 return true; 140} 141