1 /* 2 * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <assert.h> 8 #include <string.h> 9 #include <libfdt.h> 10 11 #include <platform_def.h> 12 13 #include <common/debug.h> 14 #include <common/desc_image_load.h> 15 #include <common/tbbr/tbbr_img_def.h> 16 #if TRUSTED_BOARD_BOOT 17 #include <drivers/auth/mbedtls/mbedtls_config.h> 18 #endif 19 #include <lib/fconf/fconf.h> 20 #include <lib/fconf/fconf_dyn_cfg_getter.h> 21 #include <lib/fconf/fconf_tbbr_getter.h> 22 #include <plat/arm/common/arm_dyn_cfg_helpers.h> 23 #include <plat/arm/common/plat_arm.h> 24 25 #if TRUSTED_BOARD_BOOT 26 27 static void *mbedtls_heap_addr; 28 static size_t mbedtls_heap_size; 29 30 /* 31 * This function is the implementation of the shared Mbed TLS heap between 32 * BL1 and BL2 for Arm platforms. The shared heap address is passed from BL1 33 * to BL2 with a pointer. This pointer resides inside the TB_FW_CONFIG file 34 * which is a DTB. 35 * 36 * This function is placed inside an #if directive for the below reasons: 37 * - To allocate space for the Mbed TLS heap --only if-- Trusted Board Boot 38 * is enabled. 39 * - This implementation requires the DTB to be present so that BL1 has a 40 * mechanism to pass the pointer to BL2. 41 */ 42 int arm_get_mbedtls_heap(void **heap_addr, size_t *heap_size) 43 { 44 assert(heap_addr != NULL); 45 assert(heap_size != NULL); 46 47 #if defined(IMAGE_BL1) || BL2_AT_EL3 48 49 /* If in BL1 or BL2_AT_EL3 define a heap */ 50 static unsigned char heap[TF_MBEDTLS_HEAP_SIZE]; 51 52 *heap_addr = heap; 53 *heap_size = sizeof(heap); 54 mbedtls_heap_addr = heap; 55 mbedtls_heap_size = sizeof(heap); 56 57 #elif defined(IMAGE_BL2) 58 59 /* If in BL2, retrieve the already allocated heap's info from DTB */ 60 *heap_addr = FCONF_GET_PROPERTY(tbbr, dyn_config, mbedtls_heap_addr); 61 *heap_size = FCONF_GET_PROPERTY(tbbr, dyn_config, mbedtls_heap_size); 62 63 #endif 64 65 return 0; 66 } 67 68 /* 69 * Puts the shared Mbed TLS heap information to the DTB. 70 * Executed only from BL1. 71 */ 72 void arm_bl1_set_mbedtls_heap(void) 73 { 74 int err; 75 uintptr_t tb_fw_cfg_dtb; 76 77 /* 78 * If tb_fw_cfg_dtb==NULL then DTB is not present for the current 79 * platform. As such, we don't attempt to write to the DTB at all. 80 * 81 * If mbedtls_heap_addr==NULL, then it means we are using the default 82 * heap implementation. As such, BL2 will have its own heap for sure 83 * and hence there is no need to pass any information to the DTB. 84 * 85 * In the latter case, if we still wanted to write in the DTB the heap 86 * information, we would need to call plat_get_mbedtls_heap to retrieve 87 * the default heap's address and size. 88 */ 89 90 /* fconf FW_CONFIG and TB_FW_CONFIG are currently the same DTB*/ 91 tb_fw_cfg_dtb = FCONF_GET_PROPERTY(fconf, dtb, base_addr); 92 93 if ((tb_fw_cfg_dtb != 0UL) && (mbedtls_heap_addr != NULL)) { 94 /* As libfdt use void *, we can't avoid this cast */ 95 void *dtb = (void *)tb_fw_cfg_dtb; 96 97 err = arm_set_dtb_mbedtls_heap_info(dtb, 98 mbedtls_heap_addr, mbedtls_heap_size); 99 if (err < 0) { 100 ERROR("BL1: unable to write shared Mbed TLS heap information to DTB\n"); 101 panic(); 102 } 103 /* 104 * Ensure that the info written to the DTB is visible to other 105 * images. It's critical because BL2 won't be able to proceed 106 * without the heap info. 107 */ 108 flush_dcache_range(tb_fw_cfg_dtb, fdt_totalsize(dtb)); 109 } 110 } 111 112 #endif /* TRUSTED_BOARD_BOOT */ 113 114 /* 115 * BL2 utility function to initialize dynamic configuration specified by 116 * TB_FW_CONFIG. Populate the bl_mem_params_node_t of other FW_CONFIGs if 117 * specified in TB_FW_CONFIG. 118 */ 119 void arm_bl2_dyn_cfg_init(void) 120 { 121 unsigned int i; 122 bl_mem_params_node_t *cfg_mem_params = NULL; 123 uintptr_t image_base; 124 size_t image_size; 125 const unsigned int config_ids[] = { 126 HW_CONFIG_ID, 127 SOC_FW_CONFIG_ID, 128 NT_FW_CONFIG_ID, 129 #if defined(SPD_tspd) || defined(SPD_spmd) 130 /* tos_fw_config is only present for TSPD/SPMD */ 131 TOS_FW_CONFIG_ID 132 #endif 133 }; 134 135 const struct dyn_cfg_dtb_info_t *dtb_info; 136 137 /* Iterate through all the fw config IDs */ 138 for (i = 0; i < ARRAY_SIZE(config_ids); i++) { 139 /* Get the config load address and size from TB_FW_CONFIG */ 140 cfg_mem_params = get_bl_mem_params_node(config_ids[i]); 141 if (cfg_mem_params == NULL) { 142 VERBOSE("Couldn't find HW_CONFIG in bl_mem_params_node\n"); 143 continue; 144 } 145 146 dtb_info = FCONF_GET_PROPERTY(dyn_cfg, dtb, config_ids[i]); 147 if (dtb_info == NULL) { 148 VERBOSE("Couldn't find config_id %d load info in TB_FW_CONFIG\n", 149 config_ids[i]); 150 continue; 151 } 152 153 image_base = dtb_info->config_addr; 154 image_size = dtb_info->config_max_size; 155 156 /* 157 * Do some runtime checks on the load addresses of soc_fw_config, 158 * tos_fw_config, nt_fw_config. This is not a comprehensive check 159 * of all invalid addresses but to prevent trivial porting errors. 160 */ 161 if (config_ids[i] != HW_CONFIG_ID) { 162 163 if (check_uptr_overflow(image_base, image_size)) 164 continue; 165 166 #ifdef BL31_BASE 167 /* Ensure the configs don't overlap with BL31 */ 168 if ((image_base >= BL31_BASE) && 169 (image_base <= BL31_LIMIT)) 170 continue; 171 #endif 172 /* Ensure the configs are loaded in a valid address */ 173 if (image_base < ARM_BL_RAM_BASE) 174 continue; 175 #ifdef BL32_BASE 176 /* 177 * If BL32 is present, ensure that the configs don't 178 * overlap with it. 179 */ 180 if ((image_base >= BL32_BASE) && 181 (image_base <= BL32_LIMIT)) 182 continue; 183 #endif 184 } 185 186 187 cfg_mem_params->image_info.image_base = image_base; 188 cfg_mem_params->image_info.image_max_size = (uint32_t)image_size; 189 190 /* 191 * Remove the IMAGE_ATTRIB_SKIP_LOADING attribute from 192 * HW_CONFIG or FW_CONFIG nodes 193 */ 194 cfg_mem_params->image_info.h.attr &= ~IMAGE_ATTRIB_SKIP_LOADING; 195 } 196 } 197