better hardening of enc_bootloader for fault injection

bintool/bintool.cpp

@@ -201,7 +201,7 @@ void set_block_ignored(elf_file *elf, uint32_t block_addr) {
     uint32_t offset = block_addr + 4 - seg->physical_address();
     if ((content[offset] & 0x7f) != PICOBIN_BLOCK_ITEM_PARTITION_TABLE) {
         DEBUG_LOG("setting block at %08x to ignored\n", block_addr);
-        content[offset] = 0x7e;   
+        content[offset] = 0x7e;
     }
     elf->content(*seg, content);
 }
@@ -233,7 +233,7 @@ void set_block_ignored(std::vector<uint8_t> &bin, uint32_t storage_addr, uint32_
     uint32_t offset = block_addr + 4 - storage_addr;
     if ((bin[offset] & 0x7f) != PICOBIN_BLOCK_ITEM_PARTITION_TABLE) {
         DEBUG_LOG("setting block at %08x to ignored\n", block_addr);
-        bin[offset] = 0x7e;   
+        bin[offset] = 0x7e;
     }
 }
 

enc_bootloader/CMakeLists.txt

@@ -46,40 +46,64 @@ if (NOT USE_PRECOMPILED)
 
         target_compile_definitions(enc_bootloader PRIVATE
             PICO_STACK_SIZE=0x800
+            # we cannot unreset clk_peri clocked h/w as we don't configure clk_peri
+            PICO_RUNTIME_SKIP_INIT_POST_CLOCK_RESETS=1
+            RC_COUNT=0 # don't use rcp_count
+
             # 0x20080000 -> 0x20081000 doesn't overlap the stack
             ROM_CHAIN_WORKSPACE=0x20080000)
 
         target_include_directories(enc_bootloader PRIVATE ${CMAKE_CURRENT_LIST_DIR})
 
         pico_set_linker_script(enc_bootloader ${CMAKE_CURRENT_LIST_DIR}/memmap_mbedtls.ld)
     else()
-        target_sources(enc_bootloader PRIVATE aes.S)
+        target_sources(enc_bootloader PRIVATE aes.S hard_entry_point.S)
 
         target_compile_definitions(enc_bootloader PRIVATE
             PICO_STACK_SIZE=0x180
             # AES Code & workspace from 0x20080044 -> 0x20081604, so 0x20080200 -> 0x20081200 is inside that
             ROM_CHAIN_WORKSPACE=0x20080200)
 
         pico_set_linker_script(enc_bootloader ${CMAKE_CURRENT_LIST_DIR}/memmap_enc_bootloader.ld)
+
+        target_compile_definitions(enc_bootloader PRIVATE
+                # The following are to reduce the size of the binary
+                PICO_NO_PROGRAM_INFO=1
+                PICO_CRT0_NO_RESET_SECTION=1
+
+                HARDENING=1
+                DOUBLE_HARDENING=1
+
+                INLINE_REF_ROUNDKEY_SHARES_S=1 # avoid need for canaries/calling check
+                INLINE_REF_ROUNDKEY_HVPERMS_S=1  # avoid need for canaries/calling check
+                INLINE_SHIFT_ROWS_S=1  # avoid need for canaries/calling check
+                INLINE_MAP_SBOX_S=1  # avoid need for canaries/calling check
+
+                CALLER_INIT_RCP_COUNT=1
+        )
     endif()
 
     target_compile_definitions(enc_bootloader PRIVATE
+        # The following are to reduce the size of the binary
         # use stack guards, as AES variables are written near the stack
         PICO_USE_STACK_GUARDS=1
-        # The following are to reduce the size of the binary
-        PICO_NO_PROGRAM_INFO=1
         # No spinlocks used
         PICO_USE_SW_SPIN_LOCKS=0
         # No heap is used
         PICO_HEAP_SIZE=0
-        # These inits are not required
-        PICO_RUNTIME_SKIP_INIT_SPIN_LOCKS_RESET=1
-        PICO_RUNTIME_SKIP_INIT_PER_CORE_IRQ_PRIORITIES=1
+        # Note all runtime init is skipped via the linker script
+
         PICO_BOOTROM_LOCKING_ENABLED=0
         # Don't need any vtor irqs
         PICO_MINIMAL_STORED_VECTOR_TABLE=1
         PICO_NO_RAM_VECTOR_TABLE=1
-        )
+
+        PICO_USE_GPIO_COPROCESSOR=0
+        FIB_WORKAROUND=1
+    )
+    if (ALLOW_DEBUGGING)
+        target_compile_definitions(enc_bootloader PRIVATE ALLOW_DEBUGGING=1)
+    endif()
 
     # print memory usage
     target_link_options(enc_bootloader PUBLIC -Wl,--print-memory-usage)