Angel Pons | 986d50e | 2020-04-02 23:48:53 +0200 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 2 | |
| 3 | #include <console/cbmem_console.h> |
| 4 | #include <console/console.h> |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 5 | #include <security/tpm/tspi/crtm.h> |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 6 | #include <security/tpm/tspi.h> |
| 7 | #include <security/tpm/tss.h> |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 8 | #include <assert.h> |
| 9 | #include <security/vboot/misc.h> |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 10 | #include <vb2_api.h> |
Joel Kitching | 2eb89c8 | 2019-04-25 17:45:12 +0800 | [diff] [blame] | 11 | #include <vb2_sha.h> |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 12 | |
Julius Werner | cd49cce | 2019-03-05 16:53:33 -0800 | [diff] [blame] | 13 | #if CONFIG(TPM1) |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 14 | static uint32_t tpm1_invoke_state_machine(void) |
| 15 | { |
Philipp Deppenwiese | 4d2af9d | 2018-08-14 09:46:55 -0700 | [diff] [blame] | 16 | uint8_t disabled; |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 17 | uint8_t deactivated; |
| 18 | uint32_t result = TPM_SUCCESS; |
| 19 | |
| 20 | /* Check that the TPM is enabled and activated. */ |
Philipp Deppenwiese | 4d2af9d | 2018-08-14 09:46:55 -0700 | [diff] [blame] | 21 | result = tlcl_get_flags(&disabled, &deactivated, NULL); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 22 | if (result != TPM_SUCCESS) { |
| 23 | printk(BIOS_ERR, "TPM: Can't read capabilities.\n"); |
| 24 | return result; |
| 25 | } |
| 26 | |
Philipp Deppenwiese | 4d2af9d | 2018-08-14 09:46:55 -0700 | [diff] [blame] | 27 | if (disabled) { |
| 28 | printk(BIOS_INFO, "TPM: is disabled. Enabling...\n"); |
| 29 | |
| 30 | result = tlcl_set_enable(); |
| 31 | if (result != TPM_SUCCESS) { |
| 32 | printk(BIOS_ERR, "TPM: Can't set enabled state.\n"); |
| 33 | return result; |
| 34 | } |
| 35 | } |
| 36 | |
Julius Werner | cd49cce | 2019-03-05 16:53:33 -0800 | [diff] [blame] | 37 | if (!!deactivated != CONFIG(TPM_DEACTIVATE)) { |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 38 | printk(BIOS_INFO, |
| 39 | "TPM: Unexpected TPM deactivated state. Toggling...\n"); |
| 40 | result = tlcl_set_deactivated(!deactivated); |
| 41 | if (result != TPM_SUCCESS) { |
| 42 | printk(BIOS_ERR, |
| 43 | "TPM: Can't toggle deactivated state.\n"); |
| 44 | return result; |
| 45 | } |
| 46 | |
| 47 | deactivated = !deactivated; |
| 48 | result = TPM_E_MUST_REBOOT; |
| 49 | } |
| 50 | |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 51 | return result; |
| 52 | } |
| 53 | #endif |
| 54 | |
Joel Kitching | 9937a06 | 2018-10-11 18:16:59 +0800 | [diff] [blame] | 55 | static uint32_t tpm_setup_s3_helper(void) |
| 56 | { |
| 57 | uint32_t result; |
| 58 | |
| 59 | result = tlcl_resume(); |
| 60 | switch (result) { |
| 61 | case TPM_SUCCESS: |
| 62 | break; |
| 63 | |
| 64 | case TPM_E_INVALID_POSTINIT: |
| 65 | /* |
| 66 | * We're on a platform where the TPM maintains power |
| 67 | * in S3, so it's already initialized. |
| 68 | */ |
| 69 | printk(BIOS_INFO, "TPM: Already initialized.\n"); |
| 70 | result = TPM_SUCCESS; |
| 71 | break; |
| 72 | |
| 73 | default: |
| 74 | printk(BIOS_ERR, "TPM: Resume failed (%#x).\n", result); |
| 75 | break; |
Joel Kitching | 9937a06 | 2018-10-11 18:16:59 +0800 | [diff] [blame] | 76 | } |
| 77 | |
| 78 | return result; |
| 79 | } |
| 80 | |
| 81 | static uint32_t tpm_setup_epilogue(uint32_t result) |
| 82 | { |
| 83 | if (result != TPM_SUCCESS) |
| 84 | post_code(POST_TPM_FAILURE); |
| 85 | else |
| 86 | printk(BIOS_INFO, "TPM: setup succeeded\n"); |
| 87 | |
| 88 | return result; |
| 89 | } |
| 90 | |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 91 | static int tpm_is_setup; |
| 92 | static inline int tspi_tpm_is_setup(void) |
| 93 | { |
Julius Werner | 23a82e8 | 2020-03-31 13:32:10 -0700 | [diff] [blame] | 94 | /* |
| 95 | * vboot_logic_executed() only starts returning true at the end of |
| 96 | * verstage, but the vboot logic itself already wants to extend PCRs |
| 97 | * before that. So in the stage where verification actually runs, we |
| 98 | * need to check tpm_is_setup. Skip that check in all other stages so |
| 99 | * this whole function can be evaluated at compile time. |
| 100 | */ |
| 101 | if (CONFIG(VBOOT)) { |
| 102 | if (verification_should_run()) |
| 103 | return tpm_is_setup; |
| 104 | return vboot_logic_executed(); |
| 105 | } |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 106 | |
| 107 | if (ENV_RAMSTAGE) |
| 108 | return tpm_is_setup; |
| 109 | |
| 110 | return 0; |
| 111 | } |
| 112 | |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 113 | /* |
| 114 | * tpm_setup starts the TPM and establishes the root of trust for the |
Jonathan Neuschäfer | 61322d7 | 2018-10-29 22:52:42 +0100 | [diff] [blame] | 115 | * anti-rollback mechanism. tpm_setup can fail for three reasons. 1 A bug. |
| 116 | * 2 a TPM hardware failure. 3 An unexpected TPM state due to some attack. In |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 117 | * general we cannot easily distinguish the kind of failure, so our strategy is |
Jonathan Neuschäfer | 61322d7 | 2018-10-29 22:52:42 +0100 | [diff] [blame] | 118 | * to reboot in recovery mode in all cases. The recovery mode calls tpm_setup |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 119 | * again, which executes (almost) the same sequence of operations. There is a |
| 120 | * good chance that, if recovery mode was entered because of a TPM failure, the |
| 121 | * failure will repeat itself. (In general this is impossible to guarantee |
| 122 | * because we have no way of creating the exact TPM initial state at the |
| 123 | * previous boot.) In recovery mode, we ignore the failure and continue, thus |
| 124 | * giving the recovery kernel a chance to fix things (that's why we don't set |
| 125 | * bGlobalLock). The choice is between a knowingly insecure device and a |
| 126 | * bricked device. |
| 127 | * |
| 128 | * As a side note, observe that we go through considerable hoops to avoid using |
| 129 | * the STCLEAR permissions for the index spaces. We do this to avoid writing |
| 130 | * to the TPM flashram at every reboot or wake-up, because of concerns about |
| 131 | * the durability of the NVRAM. |
| 132 | */ |
| 133 | uint32_t tpm_setup(int s3flag) |
| 134 | { |
| 135 | uint32_t result; |
| 136 | |
| 137 | result = tlcl_lib_init(); |
| 138 | if (result != TPM_SUCCESS) { |
| 139 | printk(BIOS_ERR, "TPM: Can't initialize.\n"); |
Joel Kitching | 9937a06 | 2018-10-11 18:16:59 +0800 | [diff] [blame] | 140 | return tpm_setup_epilogue(result); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 141 | } |
| 142 | |
| 143 | /* Handle special init for S3 resume path */ |
| 144 | if (s3flag) { |
Joel Kitching | 9937a06 | 2018-10-11 18:16:59 +0800 | [diff] [blame] | 145 | printk(BIOS_INFO, "TPM: Handle S3 resume.\n"); |
| 146 | return tpm_setup_epilogue(tpm_setup_s3_helper()); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 147 | } |
| 148 | |
| 149 | result = tlcl_startup(); |
Arthur Heymans | 6d5fcf4 | 2019-10-14 17:06:27 +0200 | [diff] [blame] | 150 | if (CONFIG(TPM_STARTUP_IGNORE_POSTINIT) |
| 151 | && result == TPM_E_INVALID_POSTINIT) { |
| 152 | printk(BIOS_DEBUG, "TPM: ignoring invalid POSTINIT\n"); |
| 153 | result = TPM_SUCCESS; |
| 154 | } |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 155 | if (result != TPM_SUCCESS) { |
| 156 | printk(BIOS_ERR, "TPM: Can't run startup command.\n"); |
Joel Kitching | 9937a06 | 2018-10-11 18:16:59 +0800 | [diff] [blame] | 157 | return tpm_setup_epilogue(result); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 158 | } |
| 159 | |
| 160 | result = tlcl_assert_physical_presence(); |
| 161 | if (result != TPM_SUCCESS) { |
| 162 | /* |
| 163 | * It is possible that the TPM was delivered with the physical |
| 164 | * presence command disabled. This tries enabling it, then |
| 165 | * tries asserting PP again. |
| 166 | */ |
| 167 | result = tlcl_physical_presence_cmd_enable(); |
| 168 | if (result != TPM_SUCCESS) { |
Joel Kitching | 9937a06 | 2018-10-11 18:16:59 +0800 | [diff] [blame] | 169 | printk(BIOS_ERR, "TPM: Can't enable physical presence command.\n"); |
| 170 | return tpm_setup_epilogue(result); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 171 | } |
| 172 | |
| 173 | result = tlcl_assert_physical_presence(); |
| 174 | if (result != TPM_SUCCESS) { |
Joel Kitching | 9937a06 | 2018-10-11 18:16:59 +0800 | [diff] [blame] | 175 | printk(BIOS_ERR, "TPM: Can't assert physical presence.\n"); |
| 176 | return tpm_setup_epilogue(result); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 177 | } |
| 178 | } |
| 179 | |
Julius Werner | cd49cce | 2019-03-05 16:53:33 -0800 | [diff] [blame] | 180 | #if CONFIG(TPM1) |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 181 | result = tpm1_invoke_state_machine(); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 182 | #endif |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 183 | if (CONFIG(TPM_MEASURED_BOOT)) |
| 184 | result = tspi_measure_cache_to_pcr(); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 185 | |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 186 | tpm_is_setup = 1; |
Joel Kitching | 9937a06 | 2018-10-11 18:16:59 +0800 | [diff] [blame] | 187 | return tpm_setup_epilogue(result); |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 188 | } |
| 189 | |
| 190 | uint32_t tpm_clear_and_reenable(void) |
| 191 | { |
| 192 | uint32_t result; |
| 193 | |
| 194 | printk(BIOS_INFO, "TPM: Clear and re-enable\n"); |
| 195 | result = tlcl_force_clear(); |
| 196 | if (result != TPM_SUCCESS) { |
| 197 | printk(BIOS_ERR, "TPM: Can't initiate a force clear.\n"); |
| 198 | return result; |
| 199 | } |
| 200 | |
Julius Werner | cd49cce | 2019-03-05 16:53:33 -0800 | [diff] [blame] | 201 | #if CONFIG(TPM1) |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 202 | result = tlcl_set_enable(); |
| 203 | if (result != TPM_SUCCESS) { |
| 204 | printk(BIOS_ERR, "TPM: Can't set enabled state.\n"); |
| 205 | return result; |
| 206 | } |
| 207 | |
| 208 | result = tlcl_set_deactivated(0); |
| 209 | if (result != TPM_SUCCESS) { |
| 210 | printk(BIOS_ERR, "TPM: Can't set deactivated state.\n"); |
| 211 | return result; |
| 212 | } |
| 213 | #endif |
| 214 | |
| 215 | return TPM_SUCCESS; |
| 216 | } |
| 217 | |
Philipp Deppenwiese | c9b7d1f | 2018-11-10 00:35:02 +0100 | [diff] [blame] | 218 | uint32_t tpm_extend_pcr(int pcr, enum vb2_hash_algorithm digest_algo, |
| 219 | uint8_t *digest, size_t digest_len, const char *name) |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 220 | { |
Philipp Deppenwiese | f849972 | 2018-07-30 01:27:47 +0200 | [diff] [blame] | 221 | uint32_t result; |
| 222 | |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 223 | if (!digest) |
| 224 | return TPM_E_IOERROR; |
| 225 | |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 226 | if (tspi_tpm_is_setup()) { |
| 227 | result = tlcl_lib_init(); |
| 228 | if (result != TPM_SUCCESS) { |
| 229 | printk(BIOS_ERR, "TPM: Can't initialize library.\n"); |
| 230 | return result; |
| 231 | } |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 232 | |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 233 | printk(BIOS_DEBUG, "TPM: Extending digest for %s into PCR %d\n", name, pcr); |
| 234 | result = tlcl_extend(pcr, digest, NULL); |
| 235 | if (result != TPM_SUCCESS) |
| 236 | return result; |
| 237 | } |
| 238 | |
| 239 | if (CONFIG(TPM_MEASURED_BOOT)) |
Philipp Deppenwiese | c9b7d1f | 2018-11-10 00:35:02 +0100 | [diff] [blame] | 240 | tcpa_log_add_table_entry(name, pcr, digest_algo, |
| 241 | digest, digest_len); |
| 242 | |
Furquan Shaikh | 38f3ffa | 2018-07-31 14:26:39 -0700 | [diff] [blame] | 243 | return TPM_SUCCESS; |
Philipp Deppenwiese | c07f8fb | 2018-02-27 19:40:52 +0100 | [diff] [blame] | 244 | } |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 245 | |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 246 | #if CONFIG(VBOOT_LIB) |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 247 | uint32_t tpm_measure_region(const struct region_device *rdev, uint8_t pcr, |
| 248 | const char *rname) |
| 249 | { |
| 250 | uint8_t digest[TPM_PCR_MAX_LEN], digest_len; |
| 251 | uint8_t buf[HASH_DATA_CHUNK_SIZE]; |
| 252 | uint32_t result, offset; |
| 253 | size_t len; |
| 254 | struct vb2_digest_context ctx; |
| 255 | enum vb2_hash_algorithm hash_alg; |
| 256 | |
| 257 | if (!rdev || !rname) |
| 258 | return TPM_E_INVALID_ARG; |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 259 | |
Julius Werner | cd49cce | 2019-03-05 16:53:33 -0800 | [diff] [blame] | 260 | if (CONFIG(TPM1)) { |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 261 | hash_alg = VB2_HASH_SHA1; |
Philipp Deppenwiese | c9b7d1f | 2018-11-10 00:35:02 +0100 | [diff] [blame] | 262 | } else { /* CONFIG_TPM2 */ |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 263 | hash_alg = VB2_HASH_SHA256; |
Philipp Deppenwiese | c9b7d1f | 2018-11-10 00:35:02 +0100 | [diff] [blame] | 264 | } |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 265 | |
| 266 | digest_len = vb2_digest_size(hash_alg); |
| 267 | assert(digest_len <= sizeof(digest)); |
| 268 | if (vb2_digest_init(&ctx, hash_alg)) { |
| 269 | printk(BIOS_ERR, "TPM: Error initializing hash.\n"); |
| 270 | return TPM_E_HASH_ERROR; |
| 271 | } |
| 272 | /* |
| 273 | * Though one can mmap the full needed region on x86 this is not the |
| 274 | * case for e.g. ARM. In order to make this code as universal as |
| 275 | * possible across different platforms read the data to hash in chunks. |
| 276 | */ |
| 277 | for (offset = 0; offset < region_device_sz(rdev); offset += len) { |
| 278 | len = MIN(sizeof(buf), region_device_sz(rdev) - offset); |
| 279 | if (rdev_readat(rdev, buf, offset, len) < 0) { |
| 280 | printk(BIOS_ERR, "TPM: Not able to read region %s.\n", |
Philipp Deppenwiese | 66f9a09 | 2018-11-08 10:59:40 +0100 | [diff] [blame] | 281 | rname); |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 282 | return TPM_E_READ_FAILURE; |
| 283 | } |
| 284 | if (vb2_digest_extend(&ctx, buf, len)) { |
| 285 | printk(BIOS_ERR, "TPM: Error extending hash.\n"); |
| 286 | return TPM_E_HASH_ERROR; |
| 287 | } |
| 288 | } |
| 289 | if (vb2_digest_finalize(&ctx, digest, digest_len)) { |
| 290 | printk(BIOS_ERR, "TPM: Error finalizing hash.\n"); |
| 291 | return TPM_E_HASH_ERROR; |
| 292 | } |
Philipp Deppenwiese | c9b7d1f | 2018-11-10 00:35:02 +0100 | [diff] [blame] | 293 | result = tpm_extend_pcr(pcr, hash_alg, digest, digest_len, rname); |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 294 | if (result != TPM_SUCCESS) { |
| 295 | printk(BIOS_ERR, "TPM: Extending hash into PCR failed.\n"); |
| 296 | return result; |
| 297 | } |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 298 | printk(BIOS_DEBUG, "TPM: Digest of %s to PCR %d %s\n", |
| 299 | rname, pcr, tspi_tpm_is_setup() ? "measured" : "logged"); |
Werner Zeh | 30cf14f | 2018-10-23 07:40:08 +0200 | [diff] [blame] | 300 | return TPM_SUCCESS; |
| 301 | } |
Bill XIE | c79e96b | 2019-08-22 20:28:36 +0800 | [diff] [blame] | 302 | #endif /* VBOOT_LIB */ |