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Diffstat (limited to 'crypto/asymmetric_keys/asym_tpm.c')
-rw-r--r--crypto/asymmetric_keys/asym_tpm.c957
1 files changed, 0 insertions, 957 deletions
diff --git a/crypto/asymmetric_keys/asym_tpm.c b/crypto/asymmetric_keys/asym_tpm.c
deleted file mode 100644
index 0959613560b9..000000000000
--- 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");
generated by cgit v1.2.3-70-g09d2 (git 2.47.1) at 2024-12-25 04:23:18 +0000