diff options
| -rw-r--r-- | src/include/memlayout.h | 5 | ||||
| -rw-r--r-- | src/vboot/Kconfig | 8 | ||||
| -rw-r--r-- | src/vboot/vboot_loader.c | 84 |
3 files changed, 50 insertions, 47 deletions
diff --git a/src/include/memlayout.h b/src/include/memlayout.h index a68b21f4d6..b39a8955c9 100644 --- a/src/include/memlayout.h +++ b/src/include/memlayout.h @@ -153,7 +153,10 @@ STR(Verstage exceeded its allotted size! (sz))); \ INCLUDE "verstage/lib/program.ld" - #define OVERLAP_VERSTAGE_ROMSTAGE(addr, size) VERSTAGE(addr, size) + #define OVERLAP_VERSTAGE_ROMSTAGE(addr, size) \ + _ = ASSERT(IS_ENABLED(CONFIG_RETURN_FROM_VERSTAGE) == 1, \ + "Must set RETURN_FROM_VERSTAGE to overlap romstage."); \ + VERSTAGE(addr, size) #else #define VERSTAGE(addr, sz) \ REGION(verstage, addr, sz, 1) diff --git a/src/vboot/Kconfig b/src/vboot/Kconfig index 0c72d4775e..a92a2fa5e1 100644 --- a/src/vboot/Kconfig +++ b/src/vboot/Kconfig @@ -83,7 +83,13 @@ config VBOOT_DISABLE_DEV_ON_RECOVERY config SEPARATE_VERSTAGE bool "Vboot verification is built into a separate stage" default n - depends on VBOOT + depends on VBOOT && VBOOT_STARTS_IN_BOOTBLOCK + help + If this option is set, vboot verification runs in a standalone stage + that is loaded from the bootblock and exits into romstage. If it is + not set, the verification code is linked directly into the bootblock + or the romstage and runs as part of that stage (cf. related options + VBOOT_STARTS_IN_BOOTBLOCK/_ROMSTAGE and RETURN_FROM_VERSTAGE). config RETURN_FROM_VERSTAGE bool "The separate verification stage returns to its caller" diff --git a/src/vboot/vboot_loader.c b/src/vboot/vboot_loader.c index 9593358e3b..3629402f7e 100644 --- a/src/vboot/vboot_loader.c +++ b/src/vboot/vboot_loader.c @@ -25,75 +25,69 @@ #include <vboot/symbols.h> #include <vboot/vboot_common.h> +/* Ensure vboot configuration is valid: */ +_Static_assert(IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK) + + IS_ENABLED(CONFIG_VBOOT_STARTS_IN_ROMSTAGE) == 1, + "vboot must either start in bootblock or romstage (not both!)"); +_Static_assert(!IS_ENABLED(CONFIG_SEPARATE_VERSTAGE) || + IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK), + "stand-alone verstage must start in (i.e. after) bootblock"); +_Static_assert(!IS_ENABLED(CONFIG_RETURN_FROM_VERSTAGE) || + IS_ENABLED(CONFIG_SEPARATE_VERSTAGE), + "return from verstage only makes sense for separate verstages"); + /* The stage loading code is compiled and entered from multiple stages. The * helper functions below attempt to provide more clarity on when certain * code should be called. */ static int verification_should_run(void) { - if (ENV_VERSTAGE && IS_ENABLED(CONFIG_SEPARATE_VERSTAGE)) - return 1; - - if (!IS_ENABLED(CONFIG_SEPARATE_VERSTAGE)) { - if (ENV_ROMSTAGE && - IS_ENABLED(CONFIG_VBOOT_STARTS_IN_ROMSTAGE)) - return 1; - if (ENV_BOOTBLOCK && - IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK)) - return 1; - } - - return 0; + if (IS_ENABLED(CONFIG_SEPARATE_VERSTAGE)) + return ENV_VERSTAGE; + else if (IS_ENABLED(CONFIG_VBOOT_STARTS_IN_ROMSTAGE)) + return ENV_ROMSTAGE; + else if (IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK)) + return ENV_BOOTBLOCK; + else + die("impossible!"); } static int verstage_should_load(void) { - if (!IS_ENABLED(CONFIG_SEPARATE_VERSTAGE)) + if (IS_ENABLED(CONFIG_SEPARATE_VERSTAGE)) + return ENV_BOOTBLOCK; + else return 0; - - if (ENV_ROMSTAGE && IS_ENABLED(CONFIG_VBOOT_STARTS_IN_ROMSTAGE)) - return 1; - - if (ENV_BOOTBLOCK && IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK)) - return 1; - - return 0; } static int vboot_executed CAR_GLOBAL; int vb2_logic_executed(void) { - /* If this stage is supposed to run the vboot logic ensure it has been - * executed. */ - if (verification_should_run() && car_get_var(vboot_executed)) + /* If we are in a stage that would load the verstage or execute the + vboot logic directly, we store the answer in a global. */ + if (verstage_should_load() || verification_should_run()) + return car_get_var(vboot_executed); + + if (IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK)) { + /* All other stages are "after the bootblock" */ + return !ENV_BOOTBLOCK; + } else if (IS_ENABLED(CONFIG_VBOOT_STARTS_IN_ROMSTAGE)) { + /* Post-RAM stages are "after the romstage" */ +#ifdef __PRE_RAM__ + return 0; +#else return 1; - - /* If this stage is supposed to load verstage and verstage is returning - * back to the calling stage check that it has been executed. */ - if (verstage_should_load() && IS_ENABLED(CONFIG_RETURN_FROM_VERSTAGE)) - if (car_get_var(vboot_executed)) - return 1; - - /* Handle all other stages post vboot execution. */ - if (!ENV_BOOTBLOCK) { - if (IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK)) - return 1; - if (IS_ENABLED(CONFIG_VBOOT_STARTS_IN_ROMSTAGE) && - !ENV_ROMSTAGE) - return 1; +#endif + } else { + die("impossible!"); } - - return 0; } static void vboot_prepare(void) { if (verification_should_run()) { - /* - * Note that this path isn't taken when - * CONFIG_RETURN_FROM_VERSTAGE is employed. - */ + /* Note: this path is not used for RETURN_FROM_VERSTAGE */ verstage_main(); car_set_var(vboot_executed, 1); vb2_save_recovery_reason_vbnv(); |