On Fri, 28 Jan 2022 at 20:57, Eric Biggers <ebiggers@xxxxxxxxxx> wrote: > > From: Eric Biggers <ebiggers@xxxxxxxxxx> > > asym_tpm keys are tied to TPM v1.2, which uses outdated crypto and has > been deprecated in favor of TPM v2.0 for over 7 years. A very quick > look at this code also immediately found some memory safety bugs > (https://lore.kernel.org/r/20220113235440.90439-2-ebiggers@xxxxxxxxxx). > Note that this code is reachable by unprivileged users. > > According to Jarkko (one of the keyrings subsystem maintainers), this > code has no practical use cases, and he isn't willing to maintain it > (https://lore.kernel.org/r/YfFZPbKkgYJGWu1Q@xxxxxx). > > Therefore, let's remove it. > > Note that this feature didn't have any documentation or tests, so we > don't need to worry about removing those. > > Cc: David Howells <dhowells@xxxxxxxxxx> > Cc: Denis Kenzior <denkenz@xxxxxxxxx> > Cc: James Morris <jmorris@xxxxxxxxx> > Cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx> > Cc: Marcel Holtmann <marcel@xxxxxxxxxxxx> > Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > --- > crypto/asymmetric_keys/Kconfig | 21 - > crypto/asymmetric_keys/Makefile | 12 - > crypto/asymmetric_keys/asym_tpm.c | 957 ---------------------------- > crypto/asymmetric_keys/tpm.asn1 | 5 - > crypto/asymmetric_keys/tpm_parser.c | 102 --- > include/crypto/asym_tpm_subtype.h | 19 - > 6 files changed, 1116 deletions(-) > delete mode 100644 crypto/asymmetric_keys/asym_tpm.c > delete mode 100644 crypto/asymmetric_keys/tpm.asn1 > delete mode 100644 crypto/asymmetric_keys/tpm_parser.c > delete mode 100644 include/crypto/asym_tpm_subtype.h > > diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig > index 1f1f004dc7577..460bc5d0a828c 100644 > --- a/crypto/asymmetric_keys/Kconfig > +++ b/crypto/asymmetric_keys/Kconfig > @@ -22,18 +22,6 @@ config ASYMMETRIC_PUBLIC_KEY_SUBTYPE > appropriate hash algorithms (such as SHA-1) must be available. > ENOPKG will be reported if the requisite algorithm is unavailable. > > -config ASYMMETRIC_TPM_KEY_SUBTYPE > - tristate "Asymmetric TPM backed private key subtype" > - depends on TCG_TPM > - depends on TRUSTED_KEYS > - select CRYPTO_HMAC > - select CRYPTO_SHA1 > - select CRYPTO_HASH_INFO > - help > - This option provides support for TPM backed private key type handling. > - Operations such as sign, verify, encrypt, decrypt are performed by > - the TPM after the private key is loaded. > - > config X509_CERTIFICATE_PARSER > tristate "X.509 certificate parser" > depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE > @@ -54,15 +42,6 @@ config PKCS8_PRIVATE_KEY_PARSER > private key data and provides the ability to instantiate a crypto key > from that data. > > -config TPM_KEY_PARSER > - tristate "TPM private key parser" > - depends on ASYMMETRIC_TPM_KEY_SUBTYPE > - select ASN1 > - help > - This option provides support for parsing TPM format blobs for > - private key data and provides the ability to instantiate a crypto key > - from that data. > - > config PKCS7_MESSAGE_PARSER > tristate "PKCS#7 message parser" > depends on X509_CERTIFICATE_PARSER > diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile > index 28b91adba2aed..c38424f55b08d 100644 > --- a/crypto/asymmetric_keys/Makefile > +++ b/crypto/asymmetric_keys/Makefile > @@ -11,7 +11,6 @@ asymmetric_keys-y := \ > signature.o > > obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o > -obj-$(CONFIG_ASYMMETRIC_TPM_KEY_SUBTYPE) += asym_tpm.o > > # > # X.509 Certificate handling > @@ -75,14 +74,3 @@ verify_signed_pefile-y := \ > > $(obj)/mscode_parser.o: $(obj)/mscode.asn1.h $(obj)/mscode.asn1.h > $(obj)/mscode.asn1.o: $(obj)/mscode.asn1.c $(obj)/mscode.asn1.h > - > -# > -# TPM private key parsing > -# > -obj-$(CONFIG_TPM_KEY_PARSER) += tpm_key_parser.o > -tpm_key_parser-y := \ > - tpm.asn1.o \ > - tpm_parser.o > - > -$(obj)/tpm_parser.o: $(obj)/tpm.asn1.h > -$(obj)/tpm.asn1.o: $(obj)/tpm.asn1.c $(obj)/tpm.asn1.h > diff --git a/crypto/asymmetric_keys/asym_tpm.c b/crypto/asymmetric_keys/asym_tpm.c > deleted file mode 100644 > index 0959613560b9e..0000000000000 > --- a/crypto/asymmetric_keys/asym_tpm.c > +++ /dev/null > @@ -1,957 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -#define pr_fmt(fmt) "ASYM-TPM: "fmt > -#include <linux/slab.h> > -#include <linux/module.h> > -#include <linux/export.h> > -#include <linux/kernel.h> > -#include <linux/seq_file.h> > -#include <linux/scatterlist.h> > -#include <linux/tpm.h> > -#include <linux/tpm_command.h> > -#include <crypto/akcipher.h> > -#include <crypto/hash.h> > -#include <crypto/sha1.h> > -#include <asm/unaligned.h> > -#include <keys/asymmetric-subtype.h> > -#include <keys/trusted_tpm.h> > -#include <crypto/asym_tpm_subtype.h> > -#include <crypto/public_key.h> > - > -#define TPM_ORD_FLUSHSPECIFIC 186 > -#define TPM_ORD_LOADKEY2 65 > -#define TPM_ORD_UNBIND 30 > -#define TPM_ORD_SIGN 60 > - > -#define TPM_RT_KEY 0x00000001 > - > -/* > - * Load a TPM key from the blob provided by userspace > - */ > -static int tpm_loadkey2(struct tpm_buf *tb, > - uint32_t keyhandle, unsigned char *keyauth, > - const unsigned char *keyblob, int keybloblen, > - uint32_t *newhandle) > -{ > - unsigned char nonceodd[TPM_NONCE_SIZE]; > - unsigned char enonce[TPM_NONCE_SIZE]; > - unsigned char authdata[SHA1_DIGEST_SIZE]; > - uint32_t authhandle = 0; > - unsigned char cont = 0; > - uint32_t ordinal; > - int ret; > - > - ordinal = htonl(TPM_ORD_LOADKEY2); > - > - /* session for loading the key */ > - ret = oiap(tb, &authhandle, enonce); > - if (ret < 0) { > - pr_info("oiap failed (%d)\n", ret); > - return ret; > - } > - > - /* generate odd nonce */ > - ret = tpm_get_random(NULL, nonceodd, TPM_NONCE_SIZE); > - if (ret < 0) { > - pr_info("tpm_get_random failed (%d)\n", ret); > - return ret; > - } > - > - /* calculate authorization HMAC value */ > - ret = TSS_authhmac(authdata, keyauth, SHA1_DIGEST_SIZE, enonce, > - nonceodd, cont, sizeof(uint32_t), &ordinal, > - keybloblen, keyblob, 0, 0); > - if (ret < 0) > - return ret; > - > - /* build the request buffer */ > - tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_LOADKEY2); > - tpm_buf_append_u32(tb, keyhandle); > - tpm_buf_append(tb, keyblob, keybloblen); > - tpm_buf_append_u32(tb, authhandle); > - tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE); > - tpm_buf_append_u8(tb, cont); > - tpm_buf_append(tb, authdata, SHA1_DIGEST_SIZE); > - > - ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE); > - if (ret < 0) { > - pr_info("authhmac failed (%d)\n", ret); > - return ret; > - } > - > - ret = TSS_checkhmac1(tb->data, ordinal, nonceodd, keyauth, > - SHA1_DIGEST_SIZE, 0, 0); > - if (ret < 0) { > - pr_info("TSS_checkhmac1 failed (%d)\n", ret); > - return ret; > - } > - > - *newhandle = LOAD32(tb->data, TPM_DATA_OFFSET); > - return 0; > -} > - > -/* > - * Execute the FlushSpecific TPM command > - */ > -static int tpm_flushspecific(struct tpm_buf *tb, uint32_t handle) > -{ > - tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_FLUSHSPECIFIC); > - tpm_buf_append_u32(tb, handle); > - tpm_buf_append_u32(tb, TPM_RT_KEY); > - > - return trusted_tpm_send(tb->data, MAX_BUF_SIZE); > -} > - > -/* > - * Decrypt a blob provided by userspace using a specific key handle. > - * The handle is a well known handle or previously loaded by e.g. LoadKey2 > - */ > -static int tpm_unbind(struct tpm_buf *tb, > - uint32_t keyhandle, unsigned char *keyauth, > - const unsigned char *blob, uint32_t bloblen, > - void *out, uint32_t outlen) > -{ > - unsigned char nonceodd[TPM_NONCE_SIZE]; > - unsigned char enonce[TPM_NONCE_SIZE]; > - unsigned char authdata[SHA1_DIGEST_SIZE]; > - uint32_t authhandle = 0; > - unsigned char cont = 0; > - uint32_t ordinal; > - uint32_t datalen; > - int ret; > - > - ordinal = htonl(TPM_ORD_UNBIND); > - datalen = htonl(bloblen); > - > - /* session for loading the key */ > - ret = oiap(tb, &authhandle, enonce); > - if (ret < 0) { > - pr_info("oiap failed (%d)\n", ret); > - return ret; > - } > - > - /* generate odd nonce */ > - ret = tpm_get_random(NULL, nonceodd, TPM_NONCE_SIZE); > - if (ret < 0) { > - pr_info("tpm_get_random failed (%d)\n", ret); > - return ret; > - } > - > - /* calculate authorization HMAC value */ > - ret = TSS_authhmac(authdata, keyauth, SHA1_DIGEST_SIZE, enonce, > - nonceodd, cont, sizeof(uint32_t), &ordinal, > - sizeof(uint32_t), &datalen, > - bloblen, blob, 0, 0); > - if (ret < 0) > - return ret; > - > - /* build the request buffer */ > - tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_UNBIND); > - tpm_buf_append_u32(tb, keyhandle); > - tpm_buf_append_u32(tb, bloblen); > - tpm_buf_append(tb, blob, bloblen); > - tpm_buf_append_u32(tb, authhandle); > - tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE); > - tpm_buf_append_u8(tb, cont); > - tpm_buf_append(tb, authdata, SHA1_DIGEST_SIZE); > - > - ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE); > - if (ret < 0) { > - pr_info("authhmac failed (%d)\n", ret); > - return ret; > - } > - > - datalen = LOAD32(tb->data, TPM_DATA_OFFSET); > - > - ret = TSS_checkhmac1(tb->data, ordinal, nonceodd, > - keyauth, SHA1_DIGEST_SIZE, > - sizeof(uint32_t), TPM_DATA_OFFSET, > - datalen, TPM_DATA_OFFSET + sizeof(uint32_t), > - 0, 0); > - if (ret < 0) { > - pr_info("TSS_checkhmac1 failed (%d)\n", ret); > - return ret; > - } > - > - memcpy(out, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), > - min(outlen, datalen)); > - > - return datalen; > -} > - > -/* > - * Sign a blob provided by userspace (that has had the hash function applied) > - * using a specific key handle. The handle is assumed to have been previously > - * loaded by e.g. LoadKey2. > - * > - * Note that the key signature scheme of the used key should be set to > - * TPM_SS_RSASSAPKCS1v15_DER. This allows the hashed input to be of any size > - * up to key_length_in_bytes - 11 and not be limited to size 20 like the > - * TPM_SS_RSASSAPKCS1v15_SHA1 signature scheme. > - */ > -static int tpm_sign(struct tpm_buf *tb, > - uint32_t keyhandle, unsigned char *keyauth, > - const unsigned char *blob, uint32_t bloblen, > - void *out, uint32_t outlen) > -{ > - unsigned char nonceodd[TPM_NONCE_SIZE]; > - unsigned char enonce[TPM_NONCE_SIZE]; > - unsigned char authdata[SHA1_DIGEST_SIZE]; > - uint32_t authhandle = 0; > - unsigned char cont = 0; > - uint32_t ordinal; > - uint32_t datalen; > - int ret; > - > - ordinal = htonl(TPM_ORD_SIGN); > - datalen = htonl(bloblen); > - > - /* session for loading the key */ > - ret = oiap(tb, &authhandle, enonce); > - if (ret < 0) { > - pr_info("oiap failed (%d)\n", ret); > - return ret; > - } > - > - /* generate odd nonce */ > - ret = tpm_get_random(NULL, nonceodd, TPM_NONCE_SIZE); > - if (ret < 0) { > - pr_info("tpm_get_random failed (%d)\n", ret); > - return ret; > - } > - > - /* calculate authorization HMAC value */ > - ret = TSS_authhmac(authdata, keyauth, SHA1_DIGEST_SIZE, enonce, > - nonceodd, cont, sizeof(uint32_t), &ordinal, > - sizeof(uint32_t), &datalen, > - bloblen, blob, 0, 0); > - if (ret < 0) > - return ret; > - > - /* build the request buffer */ > - tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_SIGN); > - tpm_buf_append_u32(tb, keyhandle); > - tpm_buf_append_u32(tb, bloblen); > - tpm_buf_append(tb, blob, bloblen); > - tpm_buf_append_u32(tb, authhandle); > - tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE); > - tpm_buf_append_u8(tb, cont); > - tpm_buf_append(tb, authdata, SHA1_DIGEST_SIZE); > - > - ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE); > - if (ret < 0) { > - pr_info("authhmac failed (%d)\n", ret); > - return ret; > - } > - > - datalen = LOAD32(tb->data, TPM_DATA_OFFSET); > - > - ret = TSS_checkhmac1(tb->data, ordinal, nonceodd, > - keyauth, SHA1_DIGEST_SIZE, > - sizeof(uint32_t), TPM_DATA_OFFSET, > - datalen, TPM_DATA_OFFSET + sizeof(uint32_t), > - 0, 0); > - if (ret < 0) { > - pr_info("TSS_checkhmac1 failed (%d)\n", ret); > - return ret; > - } > - > - memcpy(out, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), > - min(datalen, outlen)); > - > - return datalen; > -} > - > -/* Room to fit two u32 zeros for algo id and parameters length. */ > -#define SETKEY_PARAMS_SIZE (sizeof(u32) * 2) > - > -/* > - * Maximum buffer size for the BER/DER encoded public key. The public key > - * is of the form SEQUENCE { INTEGER n, INTEGER e } where n is a maximum 2048 > - * bit key and e is usually 65537 > - * The encoding overhead is: > - * - max 4 bytes for SEQUENCE > - * - max 4 bytes for INTEGER n type/length > - * - 257 bytes of n > - * - max 2 bytes for INTEGER e type/length > - * - 3 bytes of e > - * - 4+4 of zeros for set_pub_key parameters (SETKEY_PARAMS_SIZE) > - */ > -#define PUB_KEY_BUF_SIZE (4 + 4 + 257 + 2 + 3 + SETKEY_PARAMS_SIZE) > - > -/* > - * Provide a part of a description of the key for /proc/keys. > - */ > -static void asym_tpm_describe(const struct key *asymmetric_key, > - struct seq_file *m) > -{ > - struct tpm_key *tk = asymmetric_key->payload.data[asym_crypto]; > - > - if (!tk) > - return; > - > - seq_printf(m, "TPM1.2/Blob"); > -} > - > -static void asym_tpm_destroy(void *payload0, void *payload3) > -{ > - struct tpm_key *tk = payload0; > - > - if (!tk) > - return; > - > - kfree(tk->blob); > - tk->blob_len = 0; > - > - kfree(tk); > -} > - > -/* How many bytes will it take to encode the length */ > -static inline uint32_t definite_length(uint32_t len) > -{ > - if (len <= 127) > - return 1; > - if (len <= 255) > - return 2; > - return 3; > -} > - > -static inline uint8_t *encode_tag_length(uint8_t *buf, uint8_t tag, > - uint32_t len) > -{ > - *buf++ = tag; > - > - if (len <= 127) { > - buf[0] = len; > - return buf + 1; > - } > - > - if (len <= 255) { > - buf[0] = 0x81; > - buf[1] = len; > - return buf + 2; > - } > - > - buf[0] = 0x82; > - put_unaligned_be16(len, buf + 1); > - return buf + 3; > -} > - > -static uint32_t derive_pub_key(const void *pub_key, uint32_t len, uint8_t *buf) > -{ > - uint8_t *cur = buf; > - uint32_t n_len = definite_length(len) + 1 + len + 1; > - uint32_t e_len = definite_length(3) + 1 + 3; > - uint8_t e[3] = { 0x01, 0x00, 0x01 }; > - > - /* SEQUENCE */ > - cur = encode_tag_length(cur, 0x30, n_len + e_len); > - /* INTEGER n */ > - cur = encode_tag_length(cur, 0x02, len + 1); > - cur[0] = 0x00; > - memcpy(cur + 1, pub_key, len); > - cur += len + 1; > - cur = encode_tag_length(cur, 0x02, sizeof(e)); > - memcpy(cur, e, sizeof(e)); > - cur += sizeof(e); > - /* Zero parameters to satisfy set_pub_key ABI. */ > - memzero_explicit(cur, SETKEY_PARAMS_SIZE); > - > - return cur - buf; > -} > - > -/* > - * Determine the crypto algorithm name. > - */ > -static int determine_akcipher(const char *encoding, const char *hash_algo, > - char alg_name[CRYPTO_MAX_ALG_NAME]) > -{ > - if (strcmp(encoding, "pkcs1") == 0) { > - if (!hash_algo) { > - strcpy(alg_name, "pkcs1pad(rsa)"); > - return 0; > - } > - > - if (snprintf(alg_name, CRYPTO_MAX_ALG_NAME, "pkcs1pad(rsa,%s)", > - hash_algo) >= CRYPTO_MAX_ALG_NAME) > - return -EINVAL; > - > - return 0; > - } > - > - if (strcmp(encoding, "raw") == 0) { > - strcpy(alg_name, "rsa"); > - return 0; > - } > - > - return -ENOPKG; > -} > - > -/* > - * Query information about a key. > - */ > -static int tpm_key_query(const struct kernel_pkey_params *params, > - struct kernel_pkey_query *info) > -{ > - struct tpm_key *tk = params->key->payload.data[asym_crypto]; > - int ret; > - char alg_name[CRYPTO_MAX_ALG_NAME]; > - struct crypto_akcipher *tfm; > - uint8_t der_pub_key[PUB_KEY_BUF_SIZE]; > - uint32_t der_pub_key_len; > - int len; > - > - /* TPM only works on private keys, public keys still done in software */ > - ret = determine_akcipher(params->encoding, params->hash_algo, alg_name); > - if (ret < 0) > - return ret; > - > - tfm = crypto_alloc_akcipher(alg_name, 0, 0); > - if (IS_ERR(tfm)) > - return PTR_ERR(tfm); > - > - der_pub_key_len = derive_pub_key(tk->pub_key, tk->pub_key_len, > - der_pub_key); > - > - ret = crypto_akcipher_set_pub_key(tfm, der_pub_key, der_pub_key_len); > - if (ret < 0) > - goto error_free_tfm; > - > - len = crypto_akcipher_maxsize(tfm); > - > - info->key_size = tk->key_len; > - info->max_data_size = tk->key_len / 8; > - info->max_sig_size = len; > - info->max_enc_size = len; > - info->max_dec_size = tk->key_len / 8; > - > - info->supported_ops = KEYCTL_SUPPORTS_ENCRYPT | > - KEYCTL_SUPPORTS_DECRYPT | > - KEYCTL_SUPPORTS_VERIFY | > - KEYCTL_SUPPORTS_SIGN; > - > - ret = 0; > -error_free_tfm: > - crypto_free_akcipher(tfm); > - pr_devel("<==%s() = %d\n", __func__, ret); > - return ret; > -} > - > -/* > - * Encryption operation is performed with the public key. Hence it is done > - * in software > - */ > -static int tpm_key_encrypt(struct tpm_key *tk, > - struct kernel_pkey_params *params, > - const void *in, void *out) > -{ > - char alg_name[CRYPTO_MAX_ALG_NAME]; > - struct crypto_akcipher *tfm; > - struct akcipher_request *req; > - struct crypto_wait cwait; > - struct scatterlist in_sg, out_sg; > - uint8_t der_pub_key[PUB_KEY_BUF_SIZE]; > - uint32_t der_pub_key_len; > - int ret; > - > - pr_devel("==>%s()\n", __func__); > - > - ret = determine_akcipher(params->encoding, params->hash_algo, alg_name); > - if (ret < 0) > - return ret; > - > - tfm = crypto_alloc_akcipher(alg_name, 0, 0); > - if (IS_ERR(tfm)) > - return PTR_ERR(tfm); > - > - der_pub_key_len = derive_pub_key(tk->pub_key, tk->pub_key_len, > - der_pub_key); > - > - ret = crypto_akcipher_set_pub_key(tfm, der_pub_key, der_pub_key_len); > - if (ret < 0) > - goto error_free_tfm; > - > - ret = -ENOMEM; > - req = akcipher_request_alloc(tfm, GFP_KERNEL); > - if (!req) > - goto error_free_tfm; > - > - sg_init_one(&in_sg, in, params->in_len); > - sg_init_one(&out_sg, out, params->out_len); > - akcipher_request_set_crypt(req, &in_sg, &out_sg, params->in_len, > - params->out_len); > - crypto_init_wait(&cwait); > - akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | > - CRYPTO_TFM_REQ_MAY_SLEEP, > - crypto_req_done, &cwait); > - > - ret = crypto_akcipher_encrypt(req); > - ret = crypto_wait_req(ret, &cwait); > - > - if (ret == 0) > - ret = req->dst_len; > - > - akcipher_request_free(req); > -error_free_tfm: > - crypto_free_akcipher(tfm); > - pr_devel("<==%s() = %d\n", __func__, ret); > - return ret; > -} > - > -/* > - * Decryption operation is performed with the private key in the TPM. > - */ > -static int tpm_key_decrypt(struct tpm_key *tk, > - struct kernel_pkey_params *params, > - const void *in, void *out) > -{ > - struct tpm_buf tb; > - uint32_t keyhandle; > - uint8_t srkauth[SHA1_DIGEST_SIZE]; > - uint8_t keyauth[SHA1_DIGEST_SIZE]; > - int r; > - > - pr_devel("==>%s()\n", __func__); > - > - if (params->hash_algo) > - return -ENOPKG; > - > - if (strcmp(params->encoding, "pkcs1")) > - return -ENOPKG; > - > - r = tpm_buf_init(&tb, 0, 0); > - if (r) > - return r; > - > - /* TODO: Handle a non-all zero SRK authorization */ > - memset(srkauth, 0, sizeof(srkauth)); > - > - r = tpm_loadkey2(&tb, SRKHANDLE, srkauth, > - tk->blob, tk->blob_len, &keyhandle); > - if (r < 0) { > - pr_devel("loadkey2 failed (%d)\n", r); > - goto error; > - } > - > - /* TODO: Handle a non-all zero key authorization */ > - memset(keyauth, 0, sizeof(keyauth)); > - > - r = tpm_unbind(&tb, keyhandle, keyauth, > - in, params->in_len, out, params->out_len); > - if (r < 0) > - pr_devel("tpm_unbind failed (%d)\n", r); > - > - if (tpm_flushspecific(&tb, keyhandle) < 0) > - pr_devel("flushspecific failed (%d)\n", r); > - > -error: > - tpm_buf_destroy(&tb); > - pr_devel("<==%s() = %d\n", __func__, r); > - return r; > -} > - > -/* > - * Hash algorithm OIDs plus ASN.1 DER wrappings [RFC4880 sec 5.2.2]. > - */ > -static const u8 digest_info_md5[] = { > - 0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, > - 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, /* OID */ > - 0x05, 0x00, 0x04, 0x10 > -}; > - > -static const u8 digest_info_sha1[] = { > - 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, > - 0x2b, 0x0e, 0x03, 0x02, 0x1a, > - 0x05, 0x00, 0x04, 0x14 > -}; > - > -static const u8 digest_info_rmd160[] = { > - 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, > - 0x2b, 0x24, 0x03, 0x02, 0x01, > - 0x05, 0x00, 0x04, 0x14 > -}; > - > -static const u8 digest_info_sha224[] = { > - 0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, > - 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, > - 0x05, 0x00, 0x04, 0x1c > -}; > - > -static const u8 digest_info_sha256[] = { > - 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, > - 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, > - 0x05, 0x00, 0x04, 0x20 > -}; > - > -static const u8 digest_info_sha384[] = { > - 0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, > - 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, > - 0x05, 0x00, 0x04, 0x30 > -}; > - > -static const u8 digest_info_sha512[] = { > - 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, > - 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, > - 0x05, 0x00, 0x04, 0x40 > -}; > - > -static const struct asn1_template { > - const char *name; > - const u8 *data; > - size_t size; > -} asn1_templates[] = { > -#define _(X) { #X, digest_info_##X, sizeof(digest_info_##X) } > - _(md5), > - _(sha1), > - _(rmd160), > - _(sha256), > - _(sha384), > - _(sha512), > - _(sha224), > - { NULL } > -#undef _ > -}; > - > -static const struct asn1_template *lookup_asn1(const char *name) > -{ > - const struct asn1_template *p; > - > - for (p = asn1_templates; p->name; p++) > - if (strcmp(name, p->name) == 0) > - return p; > - return NULL; > -} > - > -/* > - * Sign operation is performed with the private key in the TPM. > - */ > -static int tpm_key_sign(struct tpm_key *tk, > - struct kernel_pkey_params *params, > - const void *in, void *out) > -{ > - struct tpm_buf tb; > - uint32_t keyhandle; > - uint8_t srkauth[SHA1_DIGEST_SIZE]; > - uint8_t keyauth[SHA1_DIGEST_SIZE]; > - void *asn1_wrapped = NULL; > - uint32_t in_len = params->in_len; > - int r; > - > - pr_devel("==>%s()\n", __func__); > - > - if (strcmp(params->encoding, "pkcs1")) > - return -ENOPKG; > - > - if (params->hash_algo) { > - const struct asn1_template *asn1 = > - lookup_asn1(params->hash_algo); > - > - if (!asn1) > - return -ENOPKG; > - > - /* request enough space for the ASN.1 template + input hash */ > - asn1_wrapped = kzalloc(in_len + asn1->size, GFP_KERNEL); > - if (!asn1_wrapped) > - return -ENOMEM; > - > - /* Copy ASN.1 template, then the input */ > - memcpy(asn1_wrapped, asn1->data, asn1->size); > - memcpy(asn1_wrapped + asn1->size, in, in_len); > - > - in = asn1_wrapped; > - in_len += asn1->size; > - } > - > - if (in_len > tk->key_len / 8 - 11) { > - r = -EOVERFLOW; > - goto error_free_asn1_wrapped; > - } > - > - r = tpm_buf_init(&tb, 0, 0); > - if (r) > - goto error_free_asn1_wrapped; > - > - /* TODO: Handle a non-all zero SRK authorization */ > - memset(srkauth, 0, sizeof(srkauth)); > - > - r = tpm_loadkey2(&tb, SRKHANDLE, srkauth, > - tk->blob, tk->blob_len, &keyhandle); > - if (r < 0) { > - pr_devel("loadkey2 failed (%d)\n", r); > - goto error_free_tb; > - } > - > - /* TODO: Handle a non-all zero key authorization */ > - memset(keyauth, 0, sizeof(keyauth)); > - > - r = tpm_sign(&tb, keyhandle, keyauth, in, in_len, out, params->out_len); > - if (r < 0) > - pr_devel("tpm_sign failed (%d)\n", r); > - > - if (tpm_flushspecific(&tb, keyhandle) < 0) > - pr_devel("flushspecific failed (%d)\n", r); > - > -error_free_tb: > - tpm_buf_destroy(&tb); > -error_free_asn1_wrapped: > - kfree(asn1_wrapped); > - pr_devel("<==%s() = %d\n", __func__, r); > - return r; > -} > - > -/* > - * Do encryption, decryption and signing ops. > - */ > -static int tpm_key_eds_op(struct kernel_pkey_params *params, > - const void *in, void *out) > -{ > - struct tpm_key *tk = params->key->payload.data[asym_crypto]; > - int ret = -EOPNOTSUPP; > - > - /* Perform the encryption calculation. */ > - switch (params->op) { > - case kernel_pkey_encrypt: > - ret = tpm_key_encrypt(tk, params, in, out); > - break; > - case kernel_pkey_decrypt: > - ret = tpm_key_decrypt(tk, params, in, out); > - break; > - case kernel_pkey_sign: > - ret = tpm_key_sign(tk, params, in, out); > - break; > - default: > - BUG(); > - } > - > - return ret; > -} > - > -/* > - * Verify a signature using a public key. > - */ > -static int tpm_key_verify_signature(const struct key *key, > - const struct public_key_signature *sig) > -{ > - const struct tpm_key *tk = key->payload.data[asym_crypto]; > - struct crypto_wait cwait; > - struct crypto_akcipher *tfm; > - struct akcipher_request *req; > - struct scatterlist src_sg[2]; > - char alg_name[CRYPTO_MAX_ALG_NAME]; > - uint8_t der_pub_key[PUB_KEY_BUF_SIZE]; > - uint32_t der_pub_key_len; > - int ret; > - > - pr_devel("==>%s()\n", __func__); > - > - BUG_ON(!tk); > - BUG_ON(!sig); > - BUG_ON(!sig->s); > - > - if (!sig->digest) > - return -ENOPKG; > - > - ret = determine_akcipher(sig->encoding, sig->hash_algo, alg_name); > - if (ret < 0) > - return ret; > - > - tfm = crypto_alloc_akcipher(alg_name, 0, 0); > - if (IS_ERR(tfm)) > - return PTR_ERR(tfm); > - > - der_pub_key_len = derive_pub_key(tk->pub_key, tk->pub_key_len, > - der_pub_key); > - > - ret = crypto_akcipher_set_pub_key(tfm, der_pub_key, der_pub_key_len); > - if (ret < 0) > - goto error_free_tfm; > - > - ret = -ENOMEM; > - req = akcipher_request_alloc(tfm, GFP_KERNEL); > - if (!req) > - goto error_free_tfm; > - > - sg_init_table(src_sg, 2); > - sg_set_buf(&src_sg[0], sig->s, sig->s_size); > - sg_set_buf(&src_sg[1], sig->digest, sig->digest_size); > - akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size, > - sig->digest_size); > - crypto_init_wait(&cwait); > - akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | > - CRYPTO_TFM_REQ_MAY_SLEEP, > - crypto_req_done, &cwait); > - ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait); > - > - akcipher_request_free(req); > -error_free_tfm: > - crypto_free_akcipher(tfm); > - pr_devel("<==%s() = %d\n", __func__, ret); > - if (WARN_ON_ONCE(ret > 0)) > - ret = -EINVAL; > - return ret; > -} > - > -/* > - * Parse enough information out of TPM_KEY structure: > - * TPM_STRUCT_VER -> 4 bytes > - * TPM_KEY_USAGE -> 2 bytes > - * TPM_KEY_FLAGS -> 4 bytes > - * TPM_AUTH_DATA_USAGE -> 1 byte > - * TPM_KEY_PARMS -> variable > - * UINT32 PCRInfoSize -> 4 bytes > - * BYTE* -> PCRInfoSize bytes > - * TPM_STORE_PUBKEY > - * UINT32 encDataSize; > - * BYTE* -> encDataSize; > - * > - * TPM_KEY_PARMS: > - * TPM_ALGORITHM_ID -> 4 bytes > - * TPM_ENC_SCHEME -> 2 bytes > - * TPM_SIG_SCHEME -> 2 bytes > - * UINT32 parmSize -> 4 bytes > - * BYTE* -> variable > - */ > -static int extract_key_parameters(struct tpm_key *tk) > -{ > - const void *cur = tk->blob; > - uint32_t len = tk->blob_len; > - const void *pub_key; > - uint32_t sz; > - uint32_t key_len; > - > - if (len < 11) > - return -EBADMSG; > - > - /* Ensure this is a legacy key */ > - if (get_unaligned_be16(cur + 4) != 0x0015) > - return -EBADMSG; > - > - /* Skip to TPM_KEY_PARMS */ > - cur += 11; > - len -= 11; > - > - if (len < 12) > - return -EBADMSG; > - > - /* Make sure this is an RSA key */ > - if (get_unaligned_be32(cur) != 0x00000001) > - return -EBADMSG; > - > - /* Make sure this is TPM_ES_RSAESPKCSv15 encoding scheme */ > - if (get_unaligned_be16(cur + 4) != 0x0002) > - return -EBADMSG; > - > - /* Make sure this is TPM_SS_RSASSAPKCS1v15_DER signature scheme */ > - if (get_unaligned_be16(cur + 6) != 0x0003) > - return -EBADMSG; > - > - sz = get_unaligned_be32(cur + 8); > - if (len < sz + 12) > - return -EBADMSG; > - > - /* Move to TPM_RSA_KEY_PARMS */ > - len -= 12; > - cur += 12; > - > - /* Grab the RSA key length */ > - key_len = get_unaligned_be32(cur); > - > - switch (key_len) { > - case 512: > - case 1024: > - case 1536: > - case 2048: > - break; > - default: > - return -EINVAL; > - } > - > - /* Move just past TPM_KEY_PARMS */ > - cur += sz; > - len -= sz; > - > - if (len < 4) > - return -EBADMSG; > - > - sz = get_unaligned_be32(cur); > - if (len < 4 + sz) > - return -EBADMSG; > - > - /* Move to TPM_STORE_PUBKEY */ > - cur += 4 + sz; > - len -= 4 + sz; > - > - /* Grab the size of the public key, it should jive with the key size */ > - sz = get_unaligned_be32(cur); > - if (sz > 256) > - return -EINVAL; > - > - pub_key = cur + 4; > - > - tk->key_len = key_len; > - tk->pub_key = pub_key; > - tk->pub_key_len = sz; > - > - return 0; > -} > - > -/* Given the blob, parse it and load it into the TPM */ > -struct tpm_key *tpm_key_create(const void *blob, uint32_t blob_len) > -{ > - int r; > - struct tpm_key *tk; > - > - r = tpm_is_tpm2(NULL); > - if (r < 0) > - goto error; > - > - /* We don't support TPM2 yet */ > - if (r > 0) { > - r = -ENODEV; > - goto error; > - } > - > - r = -ENOMEM; > - tk = kzalloc(sizeof(struct tpm_key), GFP_KERNEL); > - if (!tk) > - goto error; > - > - tk->blob = kmemdup(blob, blob_len, GFP_KERNEL); > - if (!tk->blob) > - goto error_memdup; > - > - tk->blob_len = blob_len; > - > - r = extract_key_parameters(tk); > - if (r < 0) > - goto error_extract; > - > - return tk; > - > -error_extract: > - kfree(tk->blob); > - tk->blob_len = 0; > -error_memdup: > - kfree(tk); > -error: > - return ERR_PTR(r); > -} > -EXPORT_SYMBOL_GPL(tpm_key_create); > - > -/* > - * TPM-based asymmetric key subtype > - */ > -struct asymmetric_key_subtype asym_tpm_subtype = { > - .owner = THIS_MODULE, > - .name = "asym_tpm", > - .name_len = sizeof("asym_tpm") - 1, > - .describe = asym_tpm_describe, > - .destroy = asym_tpm_destroy, > - .query = tpm_key_query, > - .eds_op = tpm_key_eds_op, > - .verify_signature = tpm_key_verify_signature, > -}; > -EXPORT_SYMBOL_GPL(asym_tpm_subtype); > - > -MODULE_DESCRIPTION("TPM based asymmetric key subtype"); > -MODULE_AUTHOR("Intel Corporation"); > -MODULE_LICENSE("GPL v2"); > diff --git a/crypto/asymmetric_keys/tpm.asn1 b/crypto/asymmetric_keys/tpm.asn1 > deleted file mode 100644 > index d7f194232f30a..0000000000000 > --- a/crypto/asymmetric_keys/tpm.asn1 > +++ /dev/null > @@ -1,5 +0,0 @@ > --- > --- Unencryted TPM Blob. For details of the format, see: > --- http://david.woodhou.se/draft-woodhouse-cert-best-practice.html#I-D.mavrogiannopoulos-tpmuri > --- > -PrivateKeyInfo ::= OCTET STRING ({ tpm_note_key }) > diff --git a/crypto/asymmetric_keys/tpm_parser.c b/crypto/asymmetric_keys/tpm_parser.c > deleted file mode 100644 > index 96405d8dcd98d..0000000000000 > --- a/crypto/asymmetric_keys/tpm_parser.c > +++ /dev/null > @@ -1,102 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -#define pr_fmt(fmt) "TPM-PARSER: "fmt > -#include <linux/module.h> > -#include <linux/kernel.h> > -#include <linux/export.h> > -#include <linux/slab.h> > -#include <linux/err.h> > -#include <keys/asymmetric-subtype.h> > -#include <keys/asymmetric-parser.h> > -#include <crypto/asym_tpm_subtype.h> > -#include "tpm.asn1.h" > - > -struct tpm_parse_context { > - const void *blob; > - u32 blob_len; > -}; > - > -/* > - * Note the key data of the ASN.1 blob. > - */ > -int tpm_note_key(void *context, size_t hdrlen, > - unsigned char tag, > - const void *value, size_t vlen) > -{ > - struct tpm_parse_context *ctx = context; > - > - ctx->blob = value; > - ctx->blob_len = vlen; > - > - return 0; > -} > - > -/* > - * Parse a TPM-encrypted private key blob. > - */ > -static struct tpm_key *tpm_parse(const void *data, size_t datalen) > -{ > - struct tpm_parse_context ctx; > - long ret; > - > - memset(&ctx, 0, sizeof(ctx)); > - > - /* Attempt to decode the private key */ > - ret = asn1_ber_decoder(&tpm_decoder, &ctx, data, datalen); > - if (ret < 0) > - goto error; > - > - return tpm_key_create(ctx.blob, ctx.blob_len); > - > -error: > - return ERR_PTR(ret); > -} > -/* > - * Attempt to parse a data blob for a key as a TPM private key blob. > - */ > -static int tpm_key_preparse(struct key_preparsed_payload *prep) > -{ > - struct tpm_key *tk; > - > - /* > - * TPM 1.2 keys are max 2048 bits long, so assume the blob is no > - * more than 4x that > - */ > - if (prep->datalen > 256 * 4) > - return -EMSGSIZE; > - > - tk = tpm_parse(prep->data, prep->datalen); > - > - if (IS_ERR(tk)) > - return PTR_ERR(tk); > - > - /* We're pinning the module by being linked against it */ > - __module_get(asym_tpm_subtype.owner); > - prep->payload.data[asym_subtype] = &asym_tpm_subtype; > - prep->payload.data[asym_key_ids] = NULL; > - prep->payload.data[asym_crypto] = tk; > - prep->payload.data[asym_auth] = NULL; > - prep->quotalen = 100; > - return 0; > -} > - > -static struct asymmetric_key_parser tpm_key_parser = { > - .owner = THIS_MODULE, > - .name = "tpm_parser", > - .parse = tpm_key_preparse, > -}; > - > -static int __init tpm_key_init(void) > -{ > - return register_asymmetric_key_parser(&tpm_key_parser); > -} > - > -static void __exit tpm_key_exit(void) > -{ > - unregister_asymmetric_key_parser(&tpm_key_parser); > -} > - > -module_init(tpm_key_init); > -module_exit(tpm_key_exit); > - > -MODULE_DESCRIPTION("TPM private key-blob parser"); > -MODULE_LICENSE("GPL v2"); > diff --git a/include/crypto/asym_tpm_subtype.h b/include/crypto/asym_tpm_subtype.h > deleted file mode 100644 > index 48198c36d6b9b..0000000000000 > --- a/include/crypto/asym_tpm_subtype.h > +++ /dev/null > @@ -1,19 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -#ifndef _LINUX_ASYM_TPM_SUBTYPE_H > -#define _LINUX_ASYM_TPM_SUBTYPE_H > - > -#include <linux/keyctl.h> > - > -struct tpm_key { > - void *blob; > - u32 blob_len; > - uint16_t key_len; /* Size in bits of the key */ > - const void *pub_key; /* pointer inside blob to the public key bytes */ > - uint16_t pub_key_len; /* length of the public key */ > -}; > - > -struct tpm_key *tpm_key_create(const void *blob, uint32_t blob_len); > - > -extern struct asymmetric_key_subtype asym_tpm_subtype; > - > -#endif /* _LINUX_ASYM_TPM_SUBTYPE_H */ > -- > 2.35.0 >
