Cherry-pick vboot_reference files from TOT to support crossystem

firmware/lib/vboot_firmware.c

 /* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  * High-level firmware API for loading and verifying rewritable firmware.
  * (Firmware portion)
  */
 
 #include "gbb_header.h"
 #include "load_firmware_fw.h"
 #include "rollback_index.h"
+#include "tpm_bootmode.h"
 #include "utility.h"
 #include "vboot_common.h"
 #include "vboot_nvstorage.h"
 
 /* Static variables for UpdateFirmwareBodyHash().  It's less than
  * optimal to have static variables in a library, but in UEFI the
  * caller is deep inside a different firmware stack and doesn't have a
  * good way to pass the params struct back to us. */
 typedef struct VbLoadFirmwareInternal {
   DigestContext body_digest_context;
   uint64_t body_size_accum;
 } VbLoadFirmwareInternal;
 
 
 void UpdateFirmwareBodyHash(LoadFirmwareParams* params,
                              uint8_t* data, uint64_t size) {
   VbLoadFirmwareInternal* lfi =
       (VbLoadFirmwareInternal*)params->load_firmware_internal;
 
   DigestUpdate(&lfi->body_digest_context, data, size);
   lfi->body_size_accum += size;
 }
 
 
 int LoadFirmwareSetup(void) {
+  /* TODO: handle test errors (requires passing in VbNvContext) */
+  /* TODO: record timer values (requires passing in VbSharedData) */
   /* TODO: start initializing the TPM */
   return LOAD_FIRMWARE_SUCCESS;
 }
 
 
 int LoadFirmware(LoadFirmwareParams* params) {
   VbSharedDataHeader* shared = (VbSharedDataHeader*)params->shared_data_blob;
   GoogleBinaryBlockHeader* gbb = (GoogleBinaryBlockHeader*)params->gbb_data;
   VbPublicKey* root_key;
   VbLoadFirmwareInternal* lfi;
   VbNvContext* vnc = params->nv_context;
 
   uint32_t try_b_count;
   uint32_t tpm_version = 0;
   uint64_t lowest_version = 0xFFFFFFFF;
   uint32_t status;
+  uint32_t test_err = 0;
   int good_index = -1;
+  uint64_t boot_fw_keyblock_flags = 0;
   int is_dev;
   int index;
   int i;
 
   int retval = LOAD_FIRMWARE_RECOVERY;
   int recovery = VBNV_RECOVERY_RO_UNSPECIFIED;
 
   /* Clear output params in case we fail */
   params->firmware_index = 0;
 
   VBDEBUG(("LoadFirmware started...\n"));
 
   /* Setup NV storage */
   VbNvSetup(vnc);
 
   /* Initialize shared data structure. */
   if (0 != VbSharedDataInit(shared, params->shared_data_size)) {
     VBDEBUG(("Shared data init error\n"));
     recovery = VBNV_RECOVERY_RO_SHARED_DATA;
     goto LoadFirmwareExit;
   }
+  shared->timer_load_firmware_enter = VbGetTimer();
+
+  /* Handle test errors */
+  VbNvGet(vnc, VBNV_TEST_ERROR_FUNC, &test_err);
+  if (VBNV_TEST_ERROR_LOAD_FIRMWARE == test_err) {
+    /* Get error code */
+    VbNvGet(vnc, VBNV_TEST_ERROR_NUM, &test_err);
+    /* Clear test params so we don't repeat the error */
+    VbNvSet(vnc, VBNV_TEST_ERROR_FUNC, 0);
+    VbNvSet(vnc, VBNV_TEST_ERROR_NUM, 0);
+    /* Handle error codes */
+    switch (test_err) {
+      case LOAD_FIRMWARE_RECOVERY:
+        recovery = VBNV_RECOVERY_RO_TEST_LF;
+        goto LoadFirmwareExit;
+      case LOAD_FIRMWARE_REBOOT:
+        retval = test_err;
+        goto LoadFirmwareExit;
+      default:
+        break;
+    }
+  }
 
   /* Must have a root key from the GBB */
   if (!gbb) {
     VBDEBUG(("No GBB\n"));
     goto LoadFirmwareExit;
   }
   root_key = (VbPublicKey*)((uint8_t*)gbb + gbb->rootkey_offset);
 
   /* Parse flags */
   is_dev = (params->boot_flags & BOOT_FLAG_DEVELOPER ? 1 : 0);
+  if (is_dev)
+    shared->flags |= VBSD_LF_DEV_SWITCH_ON;
 
   /* Initialize the TPM and read rollback indices. */
   VBPERFSTART("VB_TPMI");
   status = RollbackFirmwareSetup(is_dev, &tpm_version);
   if (0 != status) {
     VBDEBUG(("Unable to setup TPM and read stored versions.\n"));
     VBPERFEND("VB_TPMI");
     if (status == TPM_E_MUST_REBOOT)
       retval = LOAD_FIRMWARE_REBOOT;
     else
       recovery = VBNV_RECOVERY_RO_TPM_ERROR;
     goto LoadFirmwareExit;
   }
+  shared->fw_version_tpm_start = tpm_version;
+  shared->fw_version_tpm = tpm_version;
   VBPERFEND("VB_TPMI");
 
   /* Read try-b count and decrement if necessary */
   VbNvGet(vnc, VBNV_TRY_B_COUNT, &try_b_count);
-  if (0 != try_b_count)
+  if (0 != try_b_count) {
     VbNvSet(vnc, VBNV_TRY_B_COUNT, try_b_count - 1);
-  VbNvSet(vnc, VBNV_TRIED_FIRMWARE_B, try_b_count ? 1 : 0);
+    shared->flags |= VBSD_FWB_TRIED;
+  }
 
   /* Allocate our internal data */
   lfi = (VbLoadFirmwareInternal*)Malloc(sizeof(VbLoadFirmwareInternal));
   if (!lfi)
     return LOAD_FIRMWARE_RECOVERY;
 
   params->load_firmware_internal = (uint8_t*)lfi;
 
   /* Loop over indices */
   for (i = 0; i < 2; i++) {
     VbKeyBlockHeader* key_block;
     uint64_t vblock_size;
     VbFirmwarePreambleHeader* preamble;
     RSAPublicKey* data_key;
     uint64_t key_version;
     uint64_t combined_version;
     uint8_t* body_digest;
+    uint8_t* check_result;
 
     /* If try B count is non-zero try firmware B first */
     index = (try_b_count ? 1 - i : i);
     if (0 == index) {
       key_block = (VbKeyBlockHeader*)params->verification_block_0;
       vblock_size = params->verification_size_0;
+      check_result = &shared->check_fw_a_result;
     } else {
       key_block = (VbKeyBlockHeader*)params->verification_block_1;
       vblock_size = params->verification_size_1;
+      check_result = &shared->check_fw_b_result;
     }
 
     /* Check the key block flags against the current boot mode.  Do this
      * before verifying the key block, since flags are faster to check than
      * the RSA signature. */
     if (!(key_block->key_block_flags &
           (is_dev ? KEY_BLOCK_FLAG_DEVELOPER_1 :
            KEY_BLOCK_FLAG_DEVELOPER_0))) {
       VBDEBUG(("Developer flag mismatch.\n"));
+      *check_result = VBSD_LF_CHECK_DEV_MISMATCH;
       continue;
     }
     /* RW firmware never runs in recovery mode. */
     if (!(key_block->key_block_flags & KEY_BLOCK_FLAG_RECOVERY_0)) {
       VBDEBUG(("Recovery flag mismatch.\n"));
+      *check_result = VBSD_LF_CHECK_REC_MISMATCH;
       continue;
     }
 
     /* Verify the key block */
     VBPERFSTART("VB_VKB");
     if ((0 != KeyBlockVerify(key_block, vblock_size, root_key, 0))) {
       VBDEBUG(("Key block verification failed.\n"));
+      *check_result = VBSD_LF_CHECK_VERIFY_KEYBLOCK;
       VBPERFEND("VB_VKB");
       continue;
     }
     VBPERFEND("VB_VKB");
 
     /* Check for rollback of key version. */
     key_version = key_block->data_key.key_version;
     if (key_version < (tpm_version >> 16)) {
       VBDEBUG(("Key rollback detected.\n"));
+      *check_result = VBSD_LF_CHECK_KEY_ROLLBACK;
       continue;
     }
 
     /* Get the key for preamble/data verification from the key block. */
     data_key = PublicKeyToRSA(&key_block->data_key);
     if (!data_key) {
       VBDEBUG(("Unable to parse data key.\n"));
+      *check_result = VBSD_LF_CHECK_DATA_KEY_PARSE;
       continue;
     }
 
     /* Verify the preamble, which follows the key block. */
     VBPERFSTART("VB_VPB");
     preamble = (VbFirmwarePreambleHeader*)((uint8_t*)key_block +
                                            key_block->key_block_size);
     if ((0 != VerifyFirmwarePreamble(preamble,
                                      vblock_size - key_block->key_block_size,
                                      data_key))) {
       VBDEBUG(("Preamble verfication failed.\n"));
+      *check_result = VBSD_LF_CHECK_VERIFY_PREAMBLE;
       RSAPublicKeyFree(data_key);
       VBPERFEND("VB_VPB");
       continue;
     }
     VBPERFEND("VB_VPB");
 
     /* Check for rollback of firmware version. */
     combined_version = ((key_version << 16) |
                         (preamble->firmware_version & 0xFFFF));
     if (combined_version < tpm_version) {
       VBDEBUG(("Firmware version rollback detected.\n"));
+      *check_result = VBSD_LF_CHECK_FW_ROLLBACK;
       RSAPublicKeyFree(data_key);
       continue;
     }
 
+    /* Header for this firmware is valid */
+    *check_result = VBSD_LF_CHECK_HEADER_VALID;
+
     /* Check for lowest key version from a valid header. */
     if (lowest_version > combined_version)
       lowest_version = combined_version;
 
     /* If we already have good firmware, no need to read another one;
      * we only needed to look at the versions to check for
      * rollback. */
     if (-1 != good_index)
       continue;
 
     /* Read the firmware data */
     VBPERFSTART("VB_RFD");
     DigestInit(&lfi->body_digest_context, data_key->algorithm);
     lfi->body_size_accum = 0;
     if (0 != GetFirmwareBody(params, index)) {
       VBDEBUG(("GetFirmwareBody() failed for index %d\n", index));
+      *check_result = VBSD_LF_CHECK_GET_FW_BODY;
       RSAPublicKeyFree(data_key);
       VBPERFEND("VB_RFD");
       continue;
     }
     if (lfi->body_size_accum != preamble->body_signature.data_size) {
       VBDEBUG(("Hash updated %d bytes but expected %d\n",
                (int)lfi->body_size_accum,
                (int)preamble->body_signature.data_size));
+      *check_result = VBSD_LF_CHECK_HASH_WRONG_SIZE;
       RSAPublicKeyFree(data_key);
       VBPERFEND("VB_RFD");
       continue;
     }
     VBPERFEND("VB_RFD");
 
     /* Verify firmware data */
     VBPERFSTART("VB_VFD");
     body_digest = DigestFinal(&lfi->body_digest_context);
     if (0 != VerifyDigest(body_digest, &preamble->body_signature, data_key)) {
       VBDEBUG(("Firmware body verification failed.\n"));
+      *check_result = VBSD_LF_CHECK_VERIFY_BODY;
       RSAPublicKeyFree(data_key);
       Free(body_digest);
       VBPERFEND("VB_VFD");
       continue;
     }
     VBPERFEND("VB_VFD");
 
     /* Done with the digest and data key, so can free them now */
     RSAPublicKeyFree(data_key);
     Free(body_digest);
 
     /* If we're still here, the firmware is valid. */
     VBDEBUG(("Firmware %d is valid.\n", index));
+    *check_result = VBSD_LF_CHECK_VALID;
     if (-1 == good_index) {
       /* Save the key we actually used */
       if (0 != VbSharedDataSetKernelKey(shared, &preamble->kernel_subkey)) {
         VBDEBUG(("Unable to save kernel subkey to shared data.\n"));
         continue;  /* The firmware signature was good, but the public
                     * key was bigger that the caller can handle. */
       }
 
       /* Save the good index, now that we're sure we can actually use
        * this firmware.  That's the one we'll boot. */
       good_index = index;
       params->firmware_index = index;
+      /* Since we now know which firmware to boot, we can update the
+       * bootable firmware key block mode. */
+      boot_fw_keyblock_flags = key_block->key_block_flags;
 
       /* If the good firmware's key version is the same as the tpm,
        * then the TPM doesn't need updating; we can stop now.
        * Otherwise, we'll check all the other headers to see if they
        * contain a newer key. */
       if (combined_version == tpm_version)
         break;
     }
   }
 
+  /* At this point, we have a good idea of how we are going to boot. Update the
+   * TPM with this state information.
+   */
+  status = SetTPMBootModeState(is_dev, 0, (int)boot_fw_keyblock_flags);
+  if (0 != status) {
+    VBDEBUG(("Unable to update the TPM with boot mode information.\n"));
+    if (status == TPM_E_MUST_REBOOT)
+      retval = LOAD_FIRMWARE_REBOOT;
+    else
+      recovery = VBNV_RECOVERY_RO_TPM_ERROR;
+    goto LoadFirmwareExit;
+  }
+
   /* Free internal data */
   Free(lfi);
   params->load_firmware_internal = NULL;
 
   /* Handle finding good firmware */
   if (good_index >= 0) {
 
     /* Update TPM if necessary */
+    shared->fw_version_lowest = (uint32_t)lowest_version;
     if (lowest_version > tpm_version) {
       VBPERFSTART("VB_TPMU");
       status = RollbackFirmwareWrite((uint32_t)lowest_version);
       VBPERFEND("VB_TPMU");
       if (0 != status) {
         VBDEBUG(("Unable to write stored versions.\n"));
         if (status == TPM_E_MUST_REBOOT)
           retval = LOAD_FIRMWARE_REBOOT;
         else
           recovery = VBNV_RECOVERY_RO_TPM_ERROR;
         goto LoadFirmwareExit;
       }
+      shared->fw_version_tpm = (uint32_t)lowest_version;
     }
 
     /* Lock firmware versions in TPM */
     VBPERFSTART("VB_TPML");
     status = RollbackFirmwareLock();
     VBPERFEND("VB_TPML");
     if (0 != status) {
       VBDEBUG(("Unable to lock firmware versions.\n"));
       if (status == TPM_E_MUST_REBOOT)
         retval = LOAD_FIRMWARE_REBOOT;
       else
         recovery = VBNV_RECOVERY_RO_TPM_ERROR;
       goto LoadFirmwareExit;
     }
 
     /* Success */
     VBDEBUG(("Will boot firmware index %d\n", (int)params->firmware_index));
+    shared->firmware_index = (uint8_t)params->firmware_index;
     retval = LOAD_FIRMWARE_SUCCESS;
   } else {
     /* No good firmware, so go to recovery mode. */
     VBDEBUG(("Alas, no good firmware.\n"));
     recovery = VBNV_RECOVERY_RO_INVALID_RW;
   }
 
 LoadFirmwareExit:
   /* Store recovery request, if any, then tear down non-volatile storage */
   VbNvSet(vnc, VBNV_RECOVERY_REQUEST, LOAD_FIRMWARE_RECOVERY == retval ?
           recovery : VBNV_RECOVERY_NOT_REQUESTED);
   VbNvTeardown(vnc);
 
+  shared->timer_load_firmware_exit = VbGetTimer();
+
   /* Note that we don't reduce params->shared_data_size to shared->data_used,
    * since we want to leave space for LoadKernel() to add to the shared data
    * buffer. */
 
   return retval;
 }
 
 
 int S3Resume(void) {
+
+  /* TODO: handle test errors (requires passing in VbNvContext) */
+
   /* Resume the TPM */
   uint32_t status = RollbackS3Resume();
 
   /* If we can't resume, just do a full reboot.  No need to go to recovery
    * mode here, since if the TPM is really broken we'll catch it on the
    * next boot. */
   if (status == TPM_SUCCESS)
     return LOAD_FIRMWARE_SUCCESS;
   else
     return LOAD_FIRMWARE_REBOOT;
 }