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 #include <plat/common/platform.h> 25 26 #if TRUSTED_BOARD_BOOT 27 28 static void *mbedtls_heap_addr; 29 static size_t mbedtls_heap_size; 30 31 /* 32 * This function is the implementation of the shared Mbed TLS heap between 33 * BL1 and BL2 for Arm platforms. The shared heap address is passed from BL1 34 * to BL2 with a pointer. This pointer resides inside the TB_FW_CONFIG file 35 * which is a DTB. 36 * 37 * This function is placed inside an #if directive for the below reasons: 38 * - To allocate space for the Mbed TLS heap --only if-- Trusted Board Boot 39 * is enabled. 40 * - This implementation requires the DTB to be present so that BL1 has a 41 * mechanism to pass the pointer to BL2. 42 */ 43 int arm_get_mbedtls_heap(void **heap_addr, size_t *heap_size) 44 { 45 assert(heap_addr != NULL); 46 assert(heap_size != NULL); 47 48 #if defined(IMAGE_BL1) || BL2_AT_EL3 49 50 /* If in BL1 or BL2_AT_EL3 define a heap */ 51 static unsigned char heap[TF_MBEDTLS_HEAP_SIZE]; 52 53 *heap_addr = heap; 54 *heap_size = sizeof(heap); 55 mbedtls_heap_addr = heap; 56 mbedtls_heap_size = sizeof(heap); 57 58 #elif defined(IMAGE_BL2) 59 60 /* If in BL2, retrieve the already allocated heap's info from DTB */ 61 *heap_addr = FCONF_GET_PROPERTY(tbbr, dyn_config, mbedtls_heap_addr); 62 *heap_size = FCONF_GET_PROPERTY(tbbr, dyn_config, mbedtls_heap_size); 63 64 #endif 65 66 return 0; 67 } 68 69 /* 70 * Puts the shared Mbed TLS heap information to the DTB. 71 * Executed only from BL1. 72 */ 73 void arm_bl1_set_mbedtls_heap(void) 74 { 75 int err; 76 uintptr_t tb_fw_cfg_dtb; 77 78 /* 79 * If tb_fw_cfg_dtb==NULL then DTB is not present for the current 80 * platform. As such, we don't attempt to write to the DTB at all. 81 * 82 * If mbedtls_heap_addr==NULL, then it means we are using the default 83 * heap implementation. As such, BL2 will have its own heap for sure 84 * and hence there is no need to pass any information to the DTB. 85 * 86 * In the latter case, if we still wanted to write in the DTB the heap 87 * information, we would need to call plat_get_mbedtls_heap to retrieve 88 * the default heap's address and size. 89 */ 90 91 /* fconf FW_CONFIG and TB_FW_CONFIG are currently the same DTB*/ 92 tb_fw_cfg_dtb = FCONF_GET_PROPERTY(fconf, dtb, base_addr); 93 94 if ((tb_fw_cfg_dtb != 0UL) && (mbedtls_heap_addr != NULL)) { 95 /* As libfdt use void *, we can't avoid this cast */ 96 void *dtb = (void *)tb_fw_cfg_dtb; 97 98 err = arm_set_dtb_mbedtls_heap_info(dtb, 99 mbedtls_heap_addr, mbedtls_heap_size); 100 if (err < 0) { 101 ERROR("BL1: unable to write shared Mbed TLS heap information to DTB\n"); 102 panic(); 103 } 104 /* 105 * Ensure that the info written to the DTB is visible to other 106 * images. It's critical because BL2 won't be able to proceed 107 * without the heap info. 108 */ 109 flush_dcache_range(tb_fw_cfg_dtb, fdt_totalsize(dtb)); 110 } 111 } 112 113 #endif /* TRUSTED_BOARD_BOOT */ 114 115 /* 116 * BL2 utility function to initialize dynamic configuration specified by 117 * TB_FW_CONFIG. Populate the bl_mem_params_node_t of other FW_CONFIGs if 118 * specified in TB_FW_CONFIG. 119 */ 120 void arm_bl2_dyn_cfg_init(void) 121 { 122 unsigned int i; 123 bl_mem_params_node_t *cfg_mem_params = NULL; 124 uintptr_t image_base; 125 size_t image_size; 126 const unsigned int config_ids[] = { 127 HW_CONFIG_ID, 128 SOC_FW_CONFIG_ID, 129 NT_FW_CONFIG_ID, 130 #if defined(SPD_tspd) || defined(SPD_spmd) 131 /* tos_fw_config is only present for TSPD/SPMD */ 132 TOS_FW_CONFIG_ID 133 #endif 134 }; 135 136 const struct dyn_cfg_dtb_info_t *dtb_info; 137 138 /* Iterate through all the fw config IDs */ 139 for (i = 0; i < ARRAY_SIZE(config_ids); i++) { 140 /* Get the config load address and size from TB_FW_CONFIG */ 141 cfg_mem_params = get_bl_mem_params_node(config_ids[i]); 142 if (cfg_mem_params == NULL) { 143 VERBOSE("Couldn't find HW_CONFIG in bl_mem_params_node\n"); 144 continue; 145 } 146 147 dtb_info = FCONF_GET_PROPERTY(dyn_cfg, dtb, config_ids[i]); 148 if (dtb_info == NULL) { 149 VERBOSE("Couldn't find config_id %d load info in TB_FW_CONFIG\n", 150 config_ids[i]); 151 continue; 152 } 153 154 image_base = dtb_info->config_addr; 155 image_size = dtb_info->config_max_size; 156 157 /* 158 * Do some runtime checks on the load addresses of soc_fw_config, 159 * tos_fw_config, nt_fw_config. This is not a comprehensive check 160 * of all invalid addresses but to prevent trivial porting errors. 161 */ 162 if (config_ids[i] != HW_CONFIG_ID) { 163 164 if (check_uptr_overflow(image_base, image_size)) 165 continue; 166 167 #ifdef BL31_BASE 168 /* Ensure the configs don't overlap with BL31 */ 169 if ((image_base >= BL31_BASE) && 170 (image_base <= BL31_LIMIT)) 171 continue; 172 #endif 173 /* Ensure the configs are loaded in a valid address */ 174 if (image_base < ARM_BL_RAM_BASE) 175 continue; 176 #ifdef BL32_BASE 177 /* 178 * If BL32 is present, ensure that the configs don't 179 * overlap with it. 180 */ 181 if ((image_base >= BL32_BASE) && 182 (image_base <= BL32_LIMIT)) 183 continue; 184 #endif 185 } 186 187 188 cfg_mem_params->image_info.image_base = image_base; 189 cfg_mem_params->image_info.image_max_size = (uint32_t)image_size; 190 191 /* 192 * Remove the IMAGE_ATTRIB_SKIP_LOADING attribute from 193 * HW_CONFIG or FW_CONFIG nodes 194 */ 195 cfg_mem_params->image_info.h.attr &= ~IMAGE_ATTRIB_SKIP_LOADING; 196 } 197 } 198