| /********************************************************************************/ |
| /* */ |
| /* NVRAM File Abstraction Layer */ |
| /* Written by Ken Goldman */ |
| /* Adapted to SWTPM by Stefan Berger */ |
| /* IBM Thomas J. Watson Research Center */ |
| /* */ |
| /* (c) Copyright IBM Corporation 2006, 2010, 2014, 2015. */ |
| /* */ |
| /* All rights reserved. */ |
| /* */ |
| /* Redistribution and use in source and binary forms, with or without */ |
| /* modification, are permitted provided that the following conditions are */ |
| /* met: */ |
| /* */ |
| /* Redistributions of source code must retain the above copyright notice, */ |
| /* this list of conditions and the following disclaimer. */ |
| /* */ |
| /* Redistributions in binary form must reproduce the above copyright */ |
| /* notice, this list of conditions and the following disclaimer in the */ |
| /* documentation and/or other materials provided with the distribution. */ |
| /* */ |
| /* Neither the names of the IBM Corporation nor the names of its */ |
| /* contributors may be used to endorse or promote products derived from */ |
| /* this software without specific prior written permission. */ |
| /* */ |
| /* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS */ |
| /* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT */ |
| /* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR */ |
| /* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT */ |
| /* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, */ |
| /* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT */ |
| /* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, */ |
| /* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY */ |
| /* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT */ |
| /* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE */ |
| /* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ |
| /********************************************************************************/ |
| |
| /* This module abstracts out all NVRAM read and write operations. |
| |
| This implementation uses standard, portable C files. |
| |
| The basic high level abstractions are: |
| |
| SWTPM_NVRAM_LoadData(); |
| SWTPM_NVRAM_StoreData(); |
| SWTPM_NVRAM_DeleteName(); |
| |
| They take a 'name' that is mapped to a rooted file name. |
| */ |
| |
| #include "config.h" |
| |
| #define _GNU_SOURCE |
| #include <stdio.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include <errno.h> |
| #include <unistd.h> |
| #include <sys/stat.h> |
| #include <arpa/inet.h> |
| #include <fcntl.h> |
| |
| #include <libtpms/tpm_error.h> |
| #include <libtpms/tpm_memory.h> |
| #include <libtpms/tpm_nvfilename.h> |
| #include <libtpms/tpm_library.h> |
| |
| #include <openssl/sha.h> |
| #include <openssl/rand.h> |
| #if OPENSSL_VERSION_NUMBER >= 0x30000000L |
| # include <openssl/core_names.h> |
| #else |
| # include <openssl/hmac.h> |
| #endif |
| |
| #if defined(__OpenBSD__) |
| # define OPENSSL_OLD_API |
| #else |
| #if OPENSSL_VERSION_NUMBER < 0x10100000 |
| #define OPENSSL_OLD_API |
| #endif |
| #endif |
| |
| #include "swtpm.h" |
| #include "swtpm_aes.h" |
| #include "swtpm_debug.h" |
| #include "swtpm_nvstore.h" |
| #include "swtpm_utils.h" |
| #include "key.h" |
| #include "logging.h" |
| #include "tpmstate.h" |
| #include "tpmlib.h" |
| #include "tlv.h" |
| #include "utils.h" |
| #include "compiler_dependencies.h" |
| |
| /* local structures */ |
| typedef struct { |
| uint8_t version; |
| uint8_t min_version; /* min. required version */ |
| uint16_t hdrsize; |
| uint16_t flags; |
| uint32_t totlen; /* length of the header and following data */ |
| } __attribute__((packed)) blobheader; |
| |
| #define BLOB_HEADER_VERSION 2 |
| |
| /* flags for blobheader */ |
| #define BLOB_FLAG_ENCRYPTED 0x01 |
| #define BLOB_FLAG_MIGRATION_ENCRYPTED 0x02 /* encrypted with migration key */ |
| #define BLOB_FLAG_MIGRATION_DATA 0x04 /* migration data are available */ |
| #define BLOB_FLAG_ENCRYPTED_256BIT_KEY 0x08 /* 256 bit file key was used */ |
| #define BLOB_FLAG_MIGRATION_256BIT_KEY 0x10 /* 256 bit migration key was used */ |
| |
| typedef struct { |
| enum encryption_mode data_encmode; |
| TPM_SYMMETRIC_KEY_DATA symkey; |
| } encryptionkey ; |
| |
| static encryptionkey filekey = { |
| .symkey = { |
| .userKeyLength = 0, |
| }, |
| }; |
| |
| static encryptionkey migrationkey = { |
| .symkey = { |
| .userKeyLength = 0, |
| }, |
| }; |
| |
| static uint32_t g_ivec_length; |
| static unsigned char *g_ivec; |
| static struct nvram_backend_ops *g_nvram_backend_ops; |
| |
| /* local prototypes */ |
| |
| static TPM_RESULT SWTPM_NVRAM_EncryptData(const encryptionkey *key, |
| tlv_data *td, |
| size_t *td_len, |
| uint16_t tag_encrypted_data, |
| const unsigned char *decrypt_data, |
| uint32_t decrypt_length, |
| uint16_t tag_ivec); |
| |
| static TPM_RESULT SWTPM_NVRAM_GetDecryptedData(const encryptionkey *key, |
| unsigned char **decrypt_data, |
| uint32_t *decrypt_length, |
| const unsigned char *encrypt_data, |
| uint32_t encrypt_length, |
| uint16_t tag_decryped_data, |
| uint16_t tag_data, |
| uint8_t hdrversion, |
| uint16_t tag_ivec, |
| uint16_t hdrflags, |
| uint16_t flag_256bitkey); |
| |
| static TPM_RESULT SWTPM_NVRAM_PrependHeader(unsigned char **data, |
| uint32_t *length, |
| uint16_t flags); |
| |
| static TPM_RESULT SWTPM_NVRAM_CheckHeader(unsigned char *data, uint32_t length, |
| uint32_t *dataoffset, |
| uint16_t *hdrflags, |
| uint8_t *hdrversion, |
| bool quiet); |
| |
| /* SWTPM_NVRAM_Init() is called once at startup. It does any NVRAM required initialization. |
| |
| This function sets some static variables that are used by all TPM's. |
| */ |
| |
| TPM_RESULT SWTPM_NVRAM_Init(void) |
| { |
| const char *backend_uri; |
| TPM_RESULT rc = 0; |
| TPM_DEBUG(" SWTPM_NVRAM_Init:\n"); |
| |
| backend_uri = tpmstate_get_backend_uri(); |
| if (!backend_uri) { |
| logprintf(STDERR_FILENO, |
| "SWTPM_NVRAM_Init: Missing backend URI.\n"); |
| rc = TPM_FAIL; |
| } else if (strncmp(backend_uri, "dir://", 6) == 0) { |
| g_nvram_backend_ops = &nvram_dir_ops; |
| } else if (strncmp(backend_uri, "file://", 7) == 0) { |
| g_nvram_backend_ops = &nvram_linear_ops; |
| } else { |
| logprintf(STDERR_FILENO, |
| "SWTPM_NVRAM_Init: Unsupported backend.\n"); |
| rc = TPM_FAIL; |
| } |
| |
| if (rc == 0) |
| rc = g_nvram_backend_ops->prepare(backend_uri); |
| |
| return rc; |
| } |
| |
| void SWTPM_NVRAM_Shutdown(void) |
| { |
| if (g_nvram_backend_ops) |
| g_nvram_backend_ops->cleanup(); |
| memset(&filekey, 0, sizeof(filekey)); |
| memset(&migrationkey, 0, sizeof(migrationkey)); |
| } |
| |
| TPM_RESULT SWTPM_NVRAM_Lock_Storage(unsigned int retries) |
| { |
| const char *backend_uri; |
| |
| if (!g_nvram_backend_ops) |
| return TPM_RETRY; |
| |
| backend_uri = tpmstate_get_backend_uri(); |
| if (!backend_uri) { |
| logprintf(STDERR_FILENO, |
| "SWTPM_NVRAM_Lock: Missing backend URI.\n"); |
| return TPM_FAIL; |
| } |
| if (g_nvram_backend_ops->lock) |
| return g_nvram_backend_ops->lock(backend_uri, retries); |
| |
| return TPM_SUCCESS; |
| } |
| |
| void SWTPM_NVRAM_Unlock(void) |
| { |
| if (g_nvram_backend_ops->unlock) |
| g_nvram_backend_ops->unlock(); |
| } |
| |
| /* SWTPM_NVRAM_GetFilenameForName() constructs a file name from the name. |
| * A temporary filename used to write to may be created. It should be rename()'d to |
| * the non-temporary filename. |
| */ |
| |
| TPM_RESULT |
| SWTPM_NVRAM_GetFilenameForName(char *filename, /* output: filename */ |
| size_t bufsize, |
| uint32_t tpm_number, |
| const char *name, /* input: abstract name */ |
| TPM_BOOL is_tempfile) /* input: is temporary file? */ |
| { |
| TPM_RESULT res = TPM_SUCCESS; |
| int n; |
| const char *suffix = ""; |
| |
| TPM_DEBUG(" SWTPM_NVRAM_GetFilenameForName: For name %s\n", name); |
| |
| switch (tpmstate_get_version()) { |
| case TPMLIB_TPM_VERSION_1_2: |
| break; |
| case TPMLIB_TPM_VERSION_2: |
| suffix = "2"; |
| break; |
| } |
| |
| if (is_tempfile) { |
| n = snprintf(filename, bufsize, "TMP%s-%02lx.%s", suffix, (unsigned long)tpm_number, name); |
| } else { |
| n = snprintf(filename, bufsize, "tpm%s-%02lx.%s", suffix, (unsigned long)tpm_number, name); |
| } |
| if ((size_t)n > bufsize) { |
| res = TPM_FAIL; |
| } |
| |
| TPM_DEBUG(" SWTPM_NVRAM_GetFilenameForName: File name %s\n", filename); |
| |
| return res; |
| } |
| |
| |
| /* Load 'data' of 'length' from the 'name'. |
| |
| 'data' must be freed after use. |
| |
| Returns |
| 0 on success. |
| TPM_RETRY and NULL,0 on non-existent file (non-fatal, first time start up) |
| TPM_FAIL on failure to load (fatal), since it should never occur |
| */ |
| |
| TPM_RESULT |
| SWTPM_NVRAM_LoadData(unsigned char **data, /* freed by caller */ |
| uint32_t *length, |
| uint32_t tpm_number, |
| const char *name) |
| { |
| TPM_RESULT rc = 0; |
| unsigned char *decrypt_data = NULL; |
| uint32_t decrypt_length; |
| uint32_t dataoffset = 0; |
| uint8_t hdrversion = 0; |
| uint16_t hdrflags; |
| const char *backend_uri = NULL; |
| |
| TPM_DEBUG(" SWTPM_NVRAM_LoadData: From file %s\n", name); |
| *data = NULL; |
| *length = 0; |
| |
| if (rc == 0) { |
| backend_uri = tpmstate_get_backend_uri(); |
| rc = g_nvram_backend_ops->load(data, length, tpm_number, name, |
| backend_uri); |
| } |
| |
| /* this function needs to return the plain data -- no tlv headers */ |
| if (rc == 0) { |
| rc = SWTPM_NVRAM_CheckHeader(*data, *length, &dataoffset, |
| &hdrflags, &hdrversion, true); |
| if (rc != 0) |
| logprintf(STDERR_FILENO, |
| "SWTPM_NVRAM_LoadData: Error from SWTPM_NVRAM_CheckHeader " |
| "rc = %d\n", rc); |
| } |
| |
| if (rc == 0) { |
| rc = SWTPM_NVRAM_GetDecryptedData(&filekey, |
| &decrypt_data, &decrypt_length, |
| *data + dataoffset, |
| *length - dataoffset, |
| TAG_ENCRYPTED_DATA, TAG_DATA, |
| hdrversion, |
| TAG_IVEC_ENCRYPTED_DATA, |
| hdrflags, |
| BLOB_FLAG_ENCRYPTED_256BIT_KEY); |
| TPM_DEBUG(" SWTPM_NVRAM_LoadData: SWTPM_NVRAM_GetDecryptedData rc = %d\n", |
| rc); |
| if (rc != 0) |
| logprintf(STDERR_FILENO, |
| "SWTPM_NVRAM_LoadData: Error from SWTPM_NVRAM_GetDecryptedData " |
| "rc = %d\n", rc); |
| } |
| |
| free(*data); |
| |
| if (rc == 0) { |
| TPM_DEBUG(" SWTPM_NVRAM_LoadData: Decrypted %u bytes of " |
| "data to %u bytes.\n", |
| *length, decrypt_length); |
| *data = decrypt_data; |
| *length = decrypt_length; |
| } else { |
| *data = NULL; |
| } |
| |
| return rc; |
| } |
| |
| /* SWTPM_NVRAM_StoreData stores 'data' of 'length' to the rooted 'filename' |
| |
| Returns |
| 0 on success |
| TPM_FAIL for other fatal errors |
| */ |
| |
| static TPM_RESULT |
| SWTPM_NVRAM_StoreData_Intern(const unsigned char *data, |
| uint32_t length, |
| uint32_t tpm_number, |
| const char *name, |
| TPM_BOOL encrypt /* encrypt if key is set */) |
| { |
| TPM_RESULT rc = 0; |
| unsigned char *filedata = NULL; |
| uint32_t filedata_length = 0; |
| tlv_data td[3]; |
| size_t td_len = 0; |
| uint16_t flags = 0; |
| const char *backend_uri = NULL; |
| |
| TPM_DEBUG(" SWTPM_NVRAM_StoreData: To name %s\n", name); |
| |
| if (rc == 0) { |
| if (encrypt && SWTPM_NVRAM_Has_FileKey()) { |
| td_len = 3; |
| rc = SWTPM_NVRAM_EncryptData(&filekey, &td[0], &td_len, |
| TAG_ENCRYPTED_DATA, data, length, |
| TAG_IVEC_ENCRYPTED_DATA); |
| if (rc) { |
| logprintf(STDERR_FILENO, |
| "SWTPM_NVRAM_EncryptData failed: 0x%02x\n", rc); |
| } else { |
| TPM_DEBUG(" SWTPM_NVRAM_StoreData: Encrypted %u bytes before " |
| "write, will write %u bytes\n", length, |
| td[0].tlv.length); |
| } |
| flags |= BLOB_FLAG_ENCRYPTED; |
| if (SWTPM_NVRAM_FileKey_Size() == SWTPM_AES256_BLOCK_SIZE) |
| flags |= BLOB_FLAG_ENCRYPTED_256BIT_KEY; |
| } else { |
| td_len = 1; |
| td[0] = TLV_DATA_CONST(TAG_DATA, length, data); |
| } |
| } |
| |
| if (rc == 0) |
| rc = tlv_data_append(&filedata, &filedata_length, td, td_len); |
| |
| if (rc == 0) |
| rc = SWTPM_NVRAM_PrependHeader(&filedata, &filedata_length, flags); |
| |
| if (rc == 0) { |
| backend_uri = tpmstate_get_backend_uri(); |
| rc = g_nvram_backend_ops->store(filedata, filedata_length, tpm_number, name, |
| backend_uri); |
| } |
| |
| tlv_data_free(td, td_len); |
| free(filedata); |
| |
| TPM_DEBUG(" SWTPM_NVRAM_StoreData: rc=%d\n", rc); |
| |
| return rc; |
| } |
| |
| TPM_RESULT SWTPM_NVRAM_StoreData(const unsigned char *data, |
| uint32_t length, |
| uint32_t tpm_number, |
| const char *name) |
| { |
| return SWTPM_NVRAM_StoreData_Intern(data, length, tpm_number, name, TRUE); |
| } |
| |
| /* SWTPM_NVRAM_DeleteName() deletes the 'name' from NVRAM |
| |
| Returns: |
| 0 on success, or if the file does not exist and mustExist is FALSE |
| TPM_FAIL if the file could not be removed, since this should never occur and there is |
| no recovery |
| |
| NOTE: Not portable code, but supported by Linux and Windows |
| */ |
| |
| TPM_RESULT SWTPM_NVRAM_DeleteName(uint32_t tpm_number, |
| const char *name, |
| TPM_BOOL mustExist) |
| { |
| const char *backend_uri = NULL; |
| backend_uri = tpmstate_get_backend_uri(); |
| |
| return g_nvram_backend_ops->delete(tpm_number, name, mustExist, |
| backend_uri); |
| } |
| |
| |
| TPM_RESULT SWTPM_NVRAM_Store_Volatile(void) |
| { |
| TPM_RESULT rc = 0; |
| char *name = TPM_VOLATILESTATE_NAME; |
| uint32_t tpm_number = 0; |
| unsigned char *buffer = NULL; |
| uint32_t buflen; |
| |
| TPM_DEBUG(" SWTPM_Store_Volatile: Name %s\n", name); |
| if (rc == 0) { |
| rc = TPMLIB_VolatileAll_Store(&buffer, &buflen); |
| } |
| if (rc == 0) { |
| /* map name to the rooted filename */ |
| rc = SWTPM_NVRAM_StoreData(buffer, buflen, tpm_number, name); |
| } |
| |
| free(buffer); |
| |
| return rc; |
| } |
| |
| static TPM_RESULT |
| SWTPM_NVRAM_KeyParamCheck(uint32_t keylen, |
| enum encryption_mode encmode) |
| { |
| TPM_RESULT rc = 0; |
| |
| if (keylen != SWTPM_AES128_BLOCK_SIZE && |
| keylen != SWTPM_AES256_BLOCK_SIZE) { |
| rc = TPM_BAD_KEY_PROPERTY; |
| } |
| switch (encmode) { |
| case ENCRYPTION_MODE_AES_CBC: |
| break; |
| case ENCRYPTION_MODE_UNKNOWN: |
| rc = TPM_BAD_MODE; |
| } |
| |
| return rc; |
| } |
| |
| size_t SWTPM_NVRAM_FileKey_Size(void) |
| { |
| return filekey.symkey.userKeyLength; |
| } |
| |
| TPM_RESULT SWTPM_NVRAM_Set_FileKey(const unsigned char *key, uint32_t keylen, |
| enum encryption_mode encmode) |
| { |
| TPM_RESULT rc; |
| |
| rc = SWTPM_NVRAM_KeyParamCheck(keylen, encmode); |
| |
| if (rc == 0) { |
| memcpy(filekey.symkey.userKey, key, keylen); |
| filekey.symkey.userKeyLength = keylen; |
| filekey.data_encmode = encmode; |
| } |
| |
| return rc; |
| } |
| |
| size_t SWTPM_NVRAM_MigrationKey_Size(void) |
| { |
| return migrationkey.symkey.userKeyLength; |
| } |
| |
| TPM_RESULT SWTPM_NVRAM_Set_MigrationKey(const unsigned char *key, |
| uint32_t keylen, |
| enum encryption_mode encmode) |
| { |
| TPM_RESULT rc; |
| |
| rc = SWTPM_NVRAM_KeyParamCheck(keylen, encmode); |
| |
| if (rc == 0) { |
| memcpy(migrationkey.symkey.userKey, key, keylen); |
| migrationkey.symkey.userKeyLength = keylen; |
| migrationkey.data_encmode = encmode; |
| } |
| |
| return rc; |
| } |
| |
| # if OPENSSL_VERSION_NUMBER >= 0x30000000L |
| |
| static int SWTPM_HMAC(unsigned char *md, unsigned int *md_len, |
| const void *key, int key_len, |
| const unsigned char *in, uint32_t in_length, |
| const unsigned char *ivec, uint32_t ivec_length) |
| { |
| OSSL_PARAM params[2]; |
| EVP_MAC_CTX *ctx; |
| EVP_MAC *hmac; |
| size_t outl; |
| int ret = 0; |
| |
| hmac = EVP_MAC_fetch(NULL, OSSL_MAC_NAME_HMAC, NULL); |
| if (!hmac) |
| return 0; |
| |
| ctx = EVP_MAC_CTX_new(hmac); |
| if (!ctx) |
| goto err; |
| |
| params[0] = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_DIGEST, |
| "sha256", 0); |
| params[1] = OSSL_PARAM_construct_end(); |
| |
| if (!EVP_MAC_init(ctx, key, key_len, params) || |
| !EVP_MAC_update(ctx, in, in_length)) |
| goto err; |
| |
| if (ivec && |
| !EVP_MAC_update(ctx, ivec, ivec_length)) |
| goto err; |
| |
| if (!EVP_MAC_final(ctx, md, &outl, *md_len)) |
| goto err; |
| *md_len = outl; |
| |
| ret = 1; |
| |
| err: |
| EVP_MAC_CTX_free(ctx); |
| EVP_MAC_free(hmac); |
| |
| return ret; |
| } |
| |
| #else |
| |
| static int SWTPM_HMAC(unsigned char *md, unsigned int *md_len, |
| const void *key, int key_len, |
| const unsigned char *in, uint32_t in_length, |
| const unsigned char *ivec, uint32_t ivec_length) |
| { |
| int ret = 0; |
| |
| #if defined OPENSSL_OLD_API |
| HMAC_CTX sctx, *ctx = &sctx; |
| |
| HMAC_CTX_init(ctx); |
| #else |
| HMAC_CTX *ctx = HMAC_CTX_new(); |
| |
| if (!ctx) |
| return 0; |
| #endif |
| |
| |
| if (!HMAC_Init_ex(ctx, key, key_len, EVP_sha256(), NULL) || |
| !HMAC_Update(ctx, in, in_length)) |
| goto err; |
| |
| if (ivec && |
| !HMAC_Update(ctx, ivec, ivec_length)) |
| goto err; |
| |
| if (!HMAC_Final(ctx, md, md_len)) |
| goto err; |
| |
| ret = 1; |
| |
| err: |
| #if defined OPENSSL_OLD_API |
| HMAC_CTX_cleanup(ctx); |
| #else |
| HMAC_CTX_free(ctx); |
| #endif |
| |
| return ret; |
| } |
| #endif /* if OPENSSL_VERSION_NUMBER >= 0x30000000L */ |
| |
| /* |
| * SWTPM_RollAndSetGlobalIvec: Create an IV for the AES CBC algorithm to use |
| * Create it with a random number every time. |
| * and leave the pointer to the data in @td. |
| * |
| * @td: pointer to tlv_data to get pointer to the random data |
| * @tag_ivec: tag for the IV tlv header |
| * @ivec_length: number of bytes needed for the ivec |
| */ |
| static TPM_RESULT SWTPM_RollAndSetGlobalIvec(tlv_data *td, |
| uint16_t tag_ivec, |
| uint32_t ivec_length) |
| { |
| unsigned char data[16]; /* do not initialize */ |
| unsigned char hashbuf[SHA256_DIGEST_LENGTH]; |
| void *p; |
| |
| if (g_ivec_length < ivec_length) { |
| p = realloc(g_ivec, ivec_length); |
| if (!p) { |
| *td = TLV_DATA_CONST(tag_ivec, 0, NULL); |
| |
| logprintf(STDOUT_FILENO, |
| "Could not allocate %u bytes.\n", ivec_length); |
| return TPM_FAIL; |
| } |
| g_ivec = p; |
| g_ivec_length = ivec_length; |
| } |
| |
| if (RAND_bytes(g_ivec, g_ivec_length) != 1) { |
| /* random data from stack to the rescue */ |
| SHA256(g_ivec, g_ivec_length, hashbuf); |
| SHA256(data, sizeof(data), hashbuf); |
| memcpy(g_ivec, hashbuf, |
| g_ivec_length < sizeof(hashbuf) |
| ? g_ivec_length |
| : sizeof(hashbuf)); |
| } |
| |
| *td = TLV_DATA_CONST(tag_ivec, g_ivec_length, g_ivec); |
| |
| return 0; |
| } |
| |
| /* |
| * SWTPM_GetIvec: Get the encryption IV from the data stream. If none is |
| * found a NULL pointer is set in *ivec, otherwise a pointer |
| * to the beginning of the IV and its length are returned. |
| */ |
| static void SWTPM_GetIvec(const unsigned char *data, uint32_t length, |
| const unsigned char **ivec, uint32_t *ivec_length, |
| uint16_t tag) |
| { |
| tlv_data td; |
| |
| if (!tlv_data_find_tag(data, length, tag, &td)) { |
| *ivec = NULL; |
| } else { |
| *ivec = td.u.const_ptr; |
| *ivec_length = td.tlv.length; |
| } |
| } |
| |
| /* |
| * SWTPM_CalcHMAC |
| * |
| * @in: input buffer to calculate HMAC on |
| * @in_length: length of input buffer |
| * @td: pointer to a tlv_data structure to receive the result with the |
| * tag, length, and pointer to an allocated buffer holding the HMAC |
| * @tpm_symmetric_key_token: symmetric key |
| * @ivec: the IV for AES CBC |
| * @ivec_length: the length of the IV |
| * |
| * Calculate an HMAC on the input buffer with payload and create an output |
| * buffer with the HMAC |
| */ |
| static TPM_RESULT |
| SWTPM_CalcHMAC(const unsigned char *in, uint32_t in_length, |
| tlv_data *td, |
| const TPM_SYMMETRIC_KEY_DATA *tpm_symmetric_key_token, |
| const unsigned char *ivec, uint32_t ivec_length) |
| { |
| TPM_RESULT rc = 0; |
| unsigned char md[EVP_MAX_MD_SIZE]; |
| unsigned int md_len = sizeof(md); |
| unsigned char *buffer = NULL; |
| |
| if (!SWTPM_HMAC(md, &md_len, |
| tpm_symmetric_key_token->userKey, |
| tpm_symmetric_key_token->userKeyLength, |
| in, in_length, ivec, ivec_length)) { |
| logprintf(STDOUT_FILENO, "HMAC calculation failed.\n"); |
| return TPM_FAIL; |
| } |
| |
| buffer = malloc(md_len); |
| |
| if (buffer) { |
| *td = TLV_DATA(TAG_HMAC, md_len, buffer); |
| memcpy(buffer, md, md_len); |
| } else { |
| logprintf(STDOUT_FILENO, |
| "Could not allocate %u bytes.\n", md_len); |
| rc = TPM_FAIL; |
| } |
| |
| return rc; |
| } |
| |
| /* |
| * SWTPM_CheckHMAC: |
| * |
| * @hmac: tlv_data with pointer to hmac bytes |
| * @encrypted_data: tlv_data with pointer to encrypted data bytes |
| * @tpm_symmetric_key_token: symmetric key |
| * @ivec: the IV for AES CBC |
| * @ivec_length: the length of the IV |
| * |
| * Verify the HMAC given the expected @hmac and the @tpm_symmetric_key_token |
| * to calculate the HMAC over the @encrypted_data. |
| */ |
| static TPM_RESULT |
| SWTPM_CheckHMAC(tlv_data *hmac, tlv_data *encrypted_data, |
| const TPM_SYMMETRIC_KEY_DATA *tpm_symmetric_key_token, |
| const unsigned char *ivec, uint32_t ivec_length) |
| { |
| const unsigned char *data; |
| uint32_t data_length; |
| unsigned int md_len; |
| unsigned char md[EVP_MAX_MD_SIZE]; |
| |
| md_len = EVP_MD_size(EVP_sha256()); |
| if (md_len > hmac->tlv.length) { |
| logprintf(STDOUT_FILENO, "Insufficient bytes for CheckHMAC()\n"); |
| return TPM_FAIL; |
| } |
| |
| data = encrypted_data->u.ptr; |
| data_length = encrypted_data->tlv.length; |
| |
| if (!SWTPM_HMAC(md, &md_len, |
| tpm_symmetric_key_token->userKey, |
| tpm_symmetric_key_token->userKeyLength, |
| data, data_length, ivec, ivec_length)) { |
| logprintf(STDOUT_FILENO, "HMAC() call failed.\n"); |
| return TPM_FAIL; |
| } |
| |
| if (memcmp(hmac->u.ptr, md, md_len)) { |
| logprintf(STDOUT_FILENO, "Verification of HMAC failed. " |
| "Data integrity is compromised\n"); |
| /* TPM_DECRYPT_ERROR indicates (to libtpms) that something |
| exists but we have the wrong key. */ |
| return TPM_DECRYPT_ERROR; |
| } |
| |
| return TPM_SUCCESS; |
| } |
| |
| /* |
| * SWTPM_CheckHash: |
| * |
| * @in: input buffer |
| * @in_length: input buffer length |
| * @out: output buffer |
| * @out_length: output buffer length |
| */ |
| static TPM_RESULT |
| SWTPM_CheckHash(const unsigned char *in, uint32_t in_length, |
| unsigned char **out, uint32_t *out_length) |
| { |
| TPM_RESULT rc = 0; |
| unsigned char *dest = NULL; |
| unsigned char hashbuf[SHA256_DIGEST_LENGTH]; |
| const unsigned char *data = &in[sizeof(hashbuf)]; |
| uint32_t data_length = in_length - sizeof(hashbuf); |
| |
| /* hash the data */ |
| SHA256(data, data_length, hashbuf); |
| |
| if (memcmp(in, hashbuf, sizeof(hashbuf))) { |
| logprintf(STDOUT_FILENO, "Verification of hash failed. " |
| "Data integrity is compromised\n"); |
| rc = TPM_FAIL; |
| } |
| |
| if (rc == 0) { |
| dest = malloc(data_length); |
| if (dest) { |
| *out = dest; |
| *out_length = data_length; |
| memcpy(dest, data, data_length); |
| } else { |
| logprintf(STDOUT_FILENO, |
| "Could not allocated %u bytes.\n", data_length); |
| rc = TPM_FAIL; |
| } |
| } |
| |
| return rc; |
| } |
| |
| static TPM_RESULT |
| SWTPM_NVRAM_EncryptData(const encryptionkey *key, |
| struct tlv_data *td, /* must provide 2 array members */ |
| size_t *td_len, |
| uint16_t tag_encrypted_data, |
| const unsigned char *data, uint32_t length, |
| uint16_t tag_ivec) |
| { |
| TPM_RESULT rc = 0; |
| TPM_RESULT irc; |
| unsigned char *tmp_data = NULL; |
| uint32_t tmp_length = 0; |
| |
| *td_len = 0; |
| |
| if (key->symkey.userKeyLength > 0) { |
| switch (key->data_encmode) { |
| case ENCRYPTION_MODE_UNKNOWN: |
| rc = TPM_BAD_MODE; |
| break; |
| case ENCRYPTION_MODE_AES_CBC: |
| irc = SWTPM_RollAndSetGlobalIvec(&td[2], tag_ivec, |
| key->symkey.userKeyLength); |
| rc = SWTPM_SymmetricKeyData_Encrypt(&tmp_data, &tmp_length, |
| data, length, &key->symkey, |
| td[2].u.const_ptr, |
| td[2].tlv.length); |
| if (rc) |
| break; |
| |
| rc = SWTPM_CalcHMAC(tmp_data, tmp_length, &td[1], &key->symkey, |
| td[2].u.const_ptr, td[2].tlv.length); |
| if (rc == 0) { |
| td[0] = TLV_DATA(tag_encrypted_data, tmp_length, tmp_data); |
| /* in case we couldn't get an IV */ |
| *td_len = (irc == 0) ? 3 : 2; |
| tmp_data = NULL; |
| } |
| break; |
| } |
| } |
| |
| if (rc) |
| tlv_data_free(td, *td_len); |
| |
| free(tmp_data); |
| |
| return rc; |
| } |
| |
| static TPM_RESULT |
| SWTPM_NVRAM_DecryptData(const encryptionkey *key, |
| unsigned char **decrypt_data, uint32_t *decrypt_length, |
| const unsigned char *data, uint32_t length, |
| uint16_t tag_encrypted_data, |
| uint8_t hdrversion, |
| uint16_t tag_ivec, uint16_t hdrflags, |
| uint16_t flag_256bitkey) |
| { |
| TPM_RESULT rc = TPM_FAIL; |
| unsigned char *tmp_data = NULL; |
| uint32_t tmp_length = 0; |
| tlv_data td[2]; |
| const unsigned char *ivec = NULL; |
| uint32_t ivec_length = 0; |
| size_t keylen; |
| |
| if (key->symkey.userKeyLength == 0) |
| return rc; |
| |
| switch (key->data_encmode) { |
| case ENCRYPTION_MODE_UNKNOWN: |
| rc = TPM_BAD_MODE; |
| break; |
| case ENCRYPTION_MODE_AES_CBC: |
| switch (hdrversion) { |
| case 1: |
| rc = SWTPM_SymmetricKeyData_Decrypt(&tmp_data, |
| &tmp_length, |
| data, length, |
| &key->symkey, |
| NULL, 0); |
| if (rc == 0) { |
| rc = SWTPM_CheckHash(tmp_data, tmp_length, |
| decrypt_data, decrypt_length); |
| } |
| break; |
| case 2: |
| keylen = (hdrflags & flag_256bitkey) |
| ? SWTPM_AES256_BLOCK_SIZE : SWTPM_AES128_BLOCK_SIZE; |
| if (keylen != key->symkey.userKeyLength) { |
| logprintf(STDERR_FILENO, |
| "Wrong decryption key. Need %zu bit key.\n", |
| keylen * 8); |
| rc = TPM_BAD_KEY_PROPERTY; |
| break; |
| } |
| |
| if (!tlv_data_find_tag(data, length, TAG_HMAC, &td[0]) || |
| !tlv_data_find_tag(data, length, tag_encrypted_data, |
| &td[1])) { |
| logprintf(STDERR_FILENO, |
| "Could not find HMAC or encrypted data (tag %u) " |
| "in byte stream.\n", tag_encrypted_data); |
| rc = TPM_FAIL; |
| break; |
| } |
| /* get the IV, if there is one */ |
| SWTPM_GetIvec(data, length, &ivec, &ivec_length, tag_ivec); |
| |
| rc = SWTPM_CheckHMAC(&td[0], &td[1], &key->symkey, |
| ivec, ivec_length); |
| if (rc == 0) { |
| rc = SWTPM_SymmetricKeyData_Decrypt(decrypt_data, |
| decrypt_length, |
| td[1].u.const_ptr, |
| td[1].tlv.length, |
| &key->symkey, |
| ivec, ivec_length); |
| } |
| break; |
| } |
| free(tmp_data); |
| } |
| |
| return rc; |
| } |
| |
| static TPM_RESULT |
| SWTPM_NVRAM_GetPlainData(unsigned char **plain, uint32_t *plain_length, |
| const unsigned char *data, uint32_t length, |
| uint16_t tag_data, |
| uint8_t hdrversion) |
| { |
| TPM_RESULT rc = 0; |
| tlv_data td[1]; |
| |
| switch (hdrversion) { |
| case 1: |
| *plain = malloc(length); |
| if (*plain) { |
| memcpy(*plain, data, length); |
| *plain_length = length; |
| } else { |
| logprintf(STDERR_FILENO, |
| "Could not allocate %u bytes.\n", length); |
| rc = TPM_FAIL; |
| } |
| break; |
| |
| case 2: |
| if (!tlv_data_find_tag(data, length, tag_data, &td[0])) { |
| logprintf(STDERR_FILENO, |
| "Could not find plain data in byte stream.\n"); |
| rc = TPM_FAIL; |
| break; |
| } |
| *plain = malloc(td->tlv.length); |
| if (*plain) { |
| memcpy(*plain, td->u.const_ptr, td->tlv.length); |
| *plain_length = td->tlv.length; |
| } else { |
| logprintf(STDERR_FILENO, |
| "Could not allocate %u bytes.\n", td->tlv.length); |
| rc = TPM_FAIL; |
| } |
| break; |
| } |
| |
| return rc; |
| } |
| |
| /* |
| * SWTPM_NVRAM_GetDecryptedData: Get the decrytped data either by just returning |
| * the data if they were not encrypted or by |
| * actually decrypting them if there is a key. |
| * The plain data is returned, meaning any TLV |
| * header has been removed. |
| * @key: the encryption key, may be NULL |
| * @decrypt_data: pointer to a pointer for the result |
| * @decrypt_length: the length of the returned data |
| * @data: input data |
| * @length: length of the input data |
| * @tag_encrypted_data: the tag the encrypted data is stored with |
| * @tag_data: the tag the plain data is stored with |
| * @hdrversion: the version found in the header that determines in what |
| * format the data is stored; tag-length-value is the format |
| * in v2 |
| * @tag_ivec: the tag for finding the IV |
| * @hdrflags: the flags from the header |
| * @flag_256bitkey: the flag in the header to check whether we expect a |
| * 256 bit key; different flag for migration and state key |
| */ |
| static TPM_RESULT |
| SWTPM_NVRAM_GetDecryptedData(const encryptionkey *key, |
| unsigned char **decrypt_data, |
| uint32_t *decrypt_length, |
| const unsigned char *data, |
| uint32_t length, |
| uint16_t tag_encrypted_data, |
| uint16_t tag_data, |
| uint8_t hdrversion, |
| uint16_t tag_ivec, |
| uint16_t hdrflags, |
| uint16_t flag_256bitkey) |
| { |
| if (key && key->symkey.userKeyLength > 0) { |
| /* we assume the data are encrypted when there's a key given */ |
| return SWTPM_NVRAM_DecryptData(key, decrypt_data, decrypt_length, |
| data, length, tag_encrypted_data, |
| hdrversion, tag_ivec, hdrflags, |
| flag_256bitkey); |
| } |
| return SWTPM_NVRAM_GetPlainData(decrypt_data, decrypt_length, |
| data, length, tag_data, hdrversion); |
| } |
| |
| /* |
| * Prepend a header in front of the state blob |
| */ |
| static TPM_RESULT |
| SWTPM_NVRAM_PrependHeader(unsigned char **data, uint32_t *length, |
| uint16_t flags) |
| { |
| unsigned char *out = NULL; |
| uint32_t out_len = sizeof(blobheader) + *length; |
| blobheader bh = { |
| .version = BLOB_HEADER_VERSION, |
| .min_version = 1, |
| .hdrsize = htons(sizeof(bh)), |
| .flags = htons(flags), |
| .totlen = htonl(out_len), |
| }; |
| TPM_RESULT res; |
| |
| out = malloc(out_len); |
| if (!out) { |
| logprintf(STDERR_FILENO, |
| "Could not allocate %u bytes.\n", out_len); |
| res = TPM_FAIL; |
| goto error; |
| } |
| |
| memcpy(out, &bh, sizeof(bh)); |
| memcpy(&out[sizeof(bh)], *data, *length); |
| |
| free(*data); |
| |
| *data = out; |
| *length = out_len; |
| |
| return TPM_SUCCESS; |
| |
| error: |
| free(*data); |
| *data = NULL; |
| *length = 0; |
| |
| return res; |
| } |
| |
| |
| static TPM_RESULT |
| SWTPM_NVRAM_CheckHeader(unsigned char *data, uint32_t length, |
| uint32_t *dataoffset, uint16_t *hdrflags, |
| uint8_t *hdrversion, bool quiet) |
| { |
| blobheader *bh = (blobheader *)data; |
| uint16_t hdrsize; |
| |
| if (length < sizeof(bh)) { |
| if (!quiet) |
| logprintf(STDERR_FILENO, |
| "not enough bytes for header: %u\n", length); |
| return TPM_BAD_PARAMETER; |
| } |
| |
| if (ntohl(bh->totlen) != length) { |
| if (!quiet) |
| logprintf(STDERR_FILENO, |
| "broken header: bh->totlen %u != %u\n", |
| htonl(bh->totlen), length); |
| return TPM_BAD_PARAMETER; |
| } |
| |
| if (bh->min_version > BLOB_HEADER_VERSION) { |
| if (!quiet) |
| logprintf(STDERR_FILENO, |
| "Minimum required version for the blob is %d, we " |
| "only support version %d\n", bh->min_version, |
| BLOB_HEADER_VERSION); |
| return TPM_BAD_VERSION; |
| } |
| |
| hdrsize = ntohs(bh->hdrsize); |
| if (hdrsize != sizeof(blobheader)) { |
| logprintf(STDERR_FILENO, |
| "bad header size: %u != %zu\n", |
| hdrsize, sizeof(blobheader)); |
| return TPM_BAD_DATASIZE; |
| } |
| |
| *hdrversion = bh->version; |
| *dataoffset = hdrsize; |
| *hdrflags = ntohs(bh->flags); |
| |
| return TPM_SUCCESS; |
| } |
| |
| /* |
| * Get the state blob with the current name; read it from the filesystem. |
| * Decrypt it if the caller asks for it and if a key is set. Return |
| * whether it's still encrypyted. |
| */ |
| TPM_RESULT SWTPM_NVRAM_GetStateBlob(unsigned char **data, |
| uint32_t *length, |
| uint32_t tpm_number, |
| const char *name, |
| TPM_BOOL decrypt, |
| TPM_BOOL *is_encrypted) |
| { |
| TPM_RESULT res; |
| uint16_t flags = 0; |
| tlv_data td[3]; |
| size_t td_len; |
| unsigned char *plain = NULL, *buffer = NULL; |
| uint32_t plain_len, buffer_len = 0; |
| |
| *data = NULL; |
| *length = 0; |
| |
| res = SWTPM_NVRAM_LoadData(&plain, &plain_len, tpm_number, name); |
| if (res) |
| return res; |
| |
| /* @plain contains unencrypted data without tlv headers */ |
| |
| /* if the user doesn't want decryption and there's a file key, we need to |
| encrypt the data */ |
| if (!decrypt && SWTPM_NVRAM_Has_FileKey()) { |
| td_len = 3; |
| res = SWTPM_NVRAM_EncryptData(&filekey, &td[0], &td_len, |
| TAG_ENCRYPTED_DATA, plain, plain_len, |
| TAG_IVEC_ENCRYPTED_DATA); |
| if (res) |
| goto err_exit; |
| |
| *is_encrypted = TRUE; |
| if (SWTPM_NVRAM_FileKey_Size() == SWTPM_AES256_BLOCK_SIZE) |
| flags |= BLOB_FLAG_ENCRYPTED_256BIT_KEY; |
| } else { |
| *is_encrypted = FALSE; |
| td[0] = TLV_DATA(TAG_DATA, plain_len, plain); |
| plain = NULL; |
| td_len = 1; |
| } |
| |
| res = tlv_data_append(&buffer, &buffer_len, td, td_len); |
| if (res) |
| goto err_exit; |
| |
| tlv_data_free(td, td_len); |
| |
| /* @buffer contains tlv data */ |
| |
| if (SWTPM_NVRAM_Has_MigrationKey()) { |
| /* we have to encrypt it now with the migration key */ |
| flags |= BLOB_FLAG_MIGRATION_ENCRYPTED; |
| if (SWTPM_NVRAM_MigrationKey_Size() == SWTPM_AES256_BLOCK_SIZE) |
| flags |= BLOB_FLAG_MIGRATION_256BIT_KEY; |
| |
| td_len = 3; |
| res = SWTPM_NVRAM_EncryptData(&migrationkey, &td[0], &td_len, |
| TAG_ENCRYPTED_MIGRATION_DATA, |
| buffer, buffer_len, |
| TAG_IVEC_ENCRYPTED_MIGRATION_DATA); |
| if (res) |
| goto err_exit; |
| } else { |
| td[0] = TLV_DATA(TAG_MIGRATION_DATA, buffer_len, buffer); |
| buffer = NULL; |
| td_len = 1; |
| } |
| flags |= BLOB_FLAG_MIGRATION_DATA; |
| |
| res = tlv_data_append(data, length, td, td_len); |
| if (res) |
| goto err_exit; |
| |
| /* put the header in clear text */ |
| if (*is_encrypted) |
| flags |= BLOB_FLAG_ENCRYPTED; |
| |
| res = SWTPM_NVRAM_PrependHeader(data, length, flags); |
| |
| err_exit: |
| tlv_data_free(td, td_len); |
| free(buffer); |
| free(plain); |
| |
| return res; |
| } |
| |
| /* |
| * Set the state blob with the given name; the caller tells us if |
| * the blob is encrypted; if it is encrypted, it will be written |
| * into the file as-is, otherwise it will be encrypted if a key is set. |
| */ |
| TPM_RESULT SWTPM_NVRAM_SetStateBlob(unsigned char *data, |
| uint32_t length, |
| TPM_BOOL is_encrypted, |
| uint32_t tpm_number SWTPM_ATTR_UNUSED, |
| uint32_t blobtype) |
| { |
| TPM_RESULT res; |
| uint32_t dataoffset; |
| unsigned char *plain = NULL, *mig_decrypt = NULL; |
| uint32_t plain_len = 0, mig_decrypt_len = 0; |
| uint16_t hdrflags; |
| enum TPMLIB_StateType st = tpmlib_blobtype_to_statetype(blobtype); |
| const char *blobname = tpmlib_get_blobname(blobtype); |
| uint8_t hdrversion; |
| |
| if (st == 0) { |
| logprintf(STDERR_FILENO, |
| "Unknown blob type %u\n", blobtype); |
| return TPM_BAD_PARAMETER; |
| } |
| |
| if (length == 0) |
| return TPMLIB_SetState(st, NULL, 0); |
| |
| res = SWTPM_NVRAM_CheckHeader(data, length, &dataoffset, &hdrflags, |
| &hdrversion, false); |
| if (res != TPM_SUCCESS) |
| return res; |
| |
| if (length - dataoffset == 0) |
| return TPMLIB_SetState(st, NULL, 0); |
| |
| /* |
| * We allow setting of blobs that were not encrypted before; |
| * we just will not decrypt them even if the migration key is |
| * set. This allows to 'upgrade' to encryption. 'Downgrading' |
| * will not be possible once a migration key was used. |
| */ |
| if ((hdrflags & BLOB_FLAG_MIGRATION_ENCRYPTED)) { |
| /* |
| * we first need to decrypt the data with the migration key |
| */ |
| if (!SWTPM_NVRAM_Has_MigrationKey()) { |
| logprintf(STDERR_FILENO, |
| "Missing migration key to decrypt %s\n", blobname); |
| return TPM_KEYNOTFOUND; |
| } |
| |
| res = SWTPM_NVRAM_DecryptData(&migrationkey, |
| &mig_decrypt, &mig_decrypt_len, |
| &data[dataoffset], length - dataoffset, |
| TAG_ENCRYPTED_MIGRATION_DATA, |
| hdrversion, |
| TAG_IVEC_ENCRYPTED_MIGRATION_DATA, |
| hdrflags, BLOB_FLAG_MIGRATION_256BIT_KEY); |
| if (res) { |
| logprintf(STDERR_FILENO, |
| "Decrypting the %s blob with the migration key failed; " |
| "res = %d\n", blobname, res); |
| return res; |
| } |
| } else { |
| res = SWTPM_NVRAM_GetPlainData(&mig_decrypt, &mig_decrypt_len, |
| &data[dataoffset], length - dataoffset, |
| TAG_MIGRATION_DATA, |
| hdrversion); |
| if (res) |
| return res; |
| } |
| |
| /* |
| * Migration key has decrytped the data; if they are still encrypted |
| * with the state encryption key, we need to decrypt them using that |
| * key now. |
| */ |
| if (is_encrypted || (hdrflags & BLOB_FLAG_ENCRYPTED)) { |
| if (!SWTPM_NVRAM_Has_FileKey()) { |
| logprintf(STDERR_FILENO, |
| "Missing state key to decrypt %s\n", blobname); |
| res = TPM_KEYNOTFOUND; |
| goto cleanup; |
| } |
| |
| res = SWTPM_NVRAM_DecryptData(&filekey, &plain, &plain_len, |
| mig_decrypt, mig_decrypt_len, |
| TAG_ENCRYPTED_DATA, |
| hdrversion, TAG_IVEC_ENCRYPTED_DATA, |
| hdrflags, BLOB_FLAG_ENCRYPTED_256BIT_KEY); |
| if (res) { |
| logprintf(STDERR_FILENO, |
| "Decrypting the %s blob with the state key " |
| "failed; res = %d\n", blobname, res); |
| goto cleanup; |
| } |
| } else { |
| res = SWTPM_NVRAM_GetPlainData(&plain, &plain_len, |
| mig_decrypt, mig_decrypt_len, |
| TAG_DATA, |
| hdrversion); |
| if (res) |
| goto cleanup; |
| } |
| |
| /* SetState will make a copy of the buffer */ |
| res = TPMLIB_SetState(st, plain, plain_len); |
| |
| free(plain); |
| |
| cleanup: |
| free(mig_decrypt); |
| |
| return res; |
| } |
| |
| /* Example JSON output: |
| * { "type": "swtpm", |
| * "states": [ "permall", "volatilestate", "savestate" ] |
| * } |
| */ |
| int SWTPM_NVRAM_PrintJson(void) |
| { |
| TPM_RESULT rc = 0; |
| const char *backend_uri; |
| const char *states[] = { |
| TPM_PERMANENT_ALL_NAME, |
| TPM_VOLATILESTATE_NAME, |
| TPM_SAVESTATE_NAME, |
| }; |
| char state_str[200] = ""; |
| size_t i, n, o, blobsize; |
| int ret = -1; |
| |
| rc = SWTPM_NVRAM_Init(); |
| if (rc == 0) { |
| o = 0; |
| backend_uri = tpmstate_get_backend_uri(); |
| |
| for (i = 0; i < ARRAY_LEN(states); i++) { |
| rc = g_nvram_backend_ops->check_state(backend_uri, states[i], |
| &blobsize); |
| if (rc == TPM_SUCCESS) { |
| n = snprintf(&state_str[o], sizeof(state_str) - o, |
| "%s {\"name\": \"%s\", \"size\": %zu}", |
| (o > 0) ? "," : "", |
| states[i], blobsize); |
| if (n >= sizeof(state_str) - o) |
| goto exit; |
| o += n; |
| } else if (rc != TPM_RETRY) { |
| /* Error other than ENOENT */ |
| goto exit; |
| } |
| } |
| printf("{ \"type\": \"swtpm\", \"states\": [%s%s] }", |
| state_str, (o > 0) ? " ": ""); |
| ret = 0; |
| } |
| |
| exit: |
| return ret; |
| } |
