sept: validate ccplex reset vector

sept/sept-secondary/src/cluster.c

@@ -138,6 +138,11 @@ void cluster_boot_cpu0(uint32_t entry)
 
     MAKE_EXCP_VEC_REG(0x100) = 0;
 
+    /* Check for reset vector lock. */
+    if (SB_CSR_0 & 2) {
+        generic_panic();
+    }
+
     /* Set reset vector. */
     SB_AA64_RESET_LOW_0 = (entry | 1);
     SB_AA64_RESET_HIGH_0 = 0;
@@ -146,6 +151,15 @@ void cluster_boot_cpu0(uint32_t entry)
     SB_CSR_0 = 2;
     (void)SB_CSR_0;
 
+    /* Validate reset vector lock + RESET_LOW/HIGH values. */
+    if (!(SB_CSR_0 & 2)) {
+        generic_panic();
+    }
+
+    if (SB_AA64_RESET_LOW_0 != (entry | 1) || SB_AA64_RESET_HIGH_0 != 0) {
+        generic_panic();
+    }
+
     /* Set CPU_STRICT_TZ_APERTURE_CHECK. */
     /* NOTE: [4.0.0+] This was added, but it breaks Exosphère. */
     /* MAKE_MC_REG(MC_TZ_SECURITY_CTRL) = 1; */

sept/sept-secondary/src/main.c

@@ -22,6 +22,7 @@
 #include "se.h"
 #include "pmc.h"
 #include "emc.h"
+#include "sysreg.h"
 #include "key_derivation.h"
 #include "timers.h"
 #include "fs_utils.h"
@@ -96,9 +97,6 @@ static void setup_env(void) {
     /* Initialize hardware. */
     nx_hwinit();
 
-    /* Check for panics. */
-    check_and_display_panic();
-
     /* Zero-fill the framebuffer and register it as printk provider. */
     video_init(g_framebuffer);
 
@@ -141,6 +139,11 @@ int sept_main(uint32_t version) {
     uint32_t stage2_version = 0;
     ScreenLogLevel log_level = SCREEN_LOG_LEVEL_NONE;
 
+    /* Validate that we can safely boot the CCPLEX. */
+    if (SB_CSR_0 & 2) {
+        generic_panic();
+    }
+
     /* Extract keys from the security engine, which TSEC FW locked down. */
     exfiltrate_keys_and_reboot_if_needed(version);
 

sept/sept-secondary/src/panic.c

@@ -13,76 +13,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
- 
+#include <stdint.h>
+#include <stddef.h>
 #include "panic.h"
 #include "di.h"
 #include "pmc.h"
+#include "se.h"
 #include "fuse.h"
 #include "utils.h"
 
 static uint32_t g_panic_code = 0;
 
-void check_and_display_panic(void) {
-    /* We also handle our own panics. */
-    /* In the case of our own panics, we assume that the display has already been initialized. */
-    bool has_panic = APBDEV_PMC_RST_STATUS_0 != 0 || g_panic_code != 0;
-    uint32_t code = g_panic_code == 0 ? APBDEV_PMC_SCRATCH200_0 : g_panic_code;
-
-    has_panic = has_panic && !(APBDEV_PMC_RST_STATUS_0 != 1 && code == PANIC_CODE_SAFEMODE);
-
-    if (has_panic) {
-        uint32_t color;
-
-        /* Check for predefined codes: */
-        switch (code & MASK(20)) {
-            case 0x01: /* Package2 signature verification failed. */
-            case 0x02: /* Package2 meta verification failed. */
-            case 0x03: /* Package2 version check failed. */
-            case 0x04: /* Package2 payload verification failed. */
-                color = PANIC_COLOR_KERNEL;
-                break;
-            case 0x05: /* Unknown SMC. */
-            case 0x06: /* Unknown Abort. */
-                color = PANIC_COLOR_SECMON_GENERIC;
-                break;
-            case 0x07: /* Invalid CPU context. */
-            case 0x08: /* Invalid SE state. */
-            case 0x09: /* CPU is already awake (2.0.0+). */
-                color = PANIC_COLOR_SECMON_DEEPSLEEP;
-                break;
-            case 0x10: /* Unknown exception. */
-                color = PANIC_COLOR_SECMON_EXCEPTION;
-                break;
-            case 0x30: /* General bootloader error. */
-            case 0x31: /* Invalid DRAM ID. */
-            case 0x32: /* Invalid size. */
-            case 0x33: /* Invalid arguement. */
-            case 0x34: /* Bad GPT. */
-            case 0x35: /* Failed to boot SafeMode. */
-            case 0x36: /* Activity monitor fired (4.0.0+). */
-                color = PANIC_COLOR_BOOTLOADER_GENERIC;
-                break;
-            case 0x40: /* Kernel panic. */
-                color = PANIC_COLOR_KERNEL;
-                break;
-            default:
-                color = code >> 20;
-                color |= color << 4;
-                break;
-        }
-
-        if (g_panic_code == 0) {
-            display_init();
-        }
-
-        display_color_screen(color);
-        wait_for_button_and_reboot();
-    } else {
-        g_panic_code = 0;
-        APBDEV_PMC_SCRATCH200_0 = 0;
-    }
-}
-
 __attribute__ ((noreturn)) void panic(uint32_t code) {
     /* Set panic code. */
     if (g_panic_code == 0) {
@@ -90,9 +31,13 @@ __attribute__ ((noreturn)) void panic(uint32_t code) {
         APBDEV_PMC_SCRATCH200_0 = code;
     }
 
+    /* Clear all keyslots. */
+    for (size_t i = 0; i < 0x10; i++) {
+        clear_aes_keyslot(i);
+    }
+
     fuse_disable_programming();
     APBDEV_PMC_CRYPTO_OP_0 = 1; /* Disable all SE operations. */
 
-    check_and_display_panic();
     while(true);
 }

sept/sept-secondary/src/panic.h

@@ -28,7 +28,6 @@
 
 #define PANIC_CODE_SAFEMODE 0x00000020
 
-void check_and_display_panic(void);
 __attribute__ ((noreturn)) void panic(uint32_t code);
 
 #endif