+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 2010 IBM Corporation
- *
- * Author:
- * David Safford <safford@us.ibm.com>
- *
- * See Documentation/security/keys/trusted-encrypted.rst
- */
-
-#include <crypto/hash_info.h>
-#include <linux/uaccess.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/slab.h>
-#include <linux/parser.h>
-#include <linux/string.h>
-#include <linux/err.h>
-#include <keys/user-type.h>
-#include <keys/trusted-type.h>
-#include <linux/key-type.h>
-#include <linux/rcupdate.h>
-#include <linux/crypto.h>
-#include <crypto/hash.h>
-#include <crypto/sha.h>
-#include <linux/capability.h>
-#include <linux/tpm.h>
-#include <linux/tpm_command.h>
-
-#include <keys/trusted.h>
-
-static const char hmac_alg[] = "hmac(sha1)";
-static const char hash_alg[] = "sha1";
-static struct tpm_chip *chip;
-static struct tpm_digest *digests;
-
-struct sdesc {
- struct shash_desc shash;
- char ctx[];
-};
-
-static struct crypto_shash *hashalg;
-static struct crypto_shash *hmacalg;
-
-static struct sdesc *init_sdesc(struct crypto_shash *alg)
-{
- struct sdesc *sdesc;
- int size;
-
- size = sizeof(struct shash_desc) + crypto_shash_descsize(alg);
- sdesc = kmalloc(size, GFP_KERNEL);
- if (!sdesc)
- return ERR_PTR(-ENOMEM);
- sdesc->shash.tfm = alg;
- return sdesc;
-}
-
-static int TSS_sha1(const unsigned char *data, unsigned int datalen,
- unsigned char *digest)
-{
- struct sdesc *sdesc;
- int ret;
-
- sdesc = init_sdesc(hashalg);
- if (IS_ERR(sdesc)) {
- pr_info("trusted_key: can't alloc %s\n", hash_alg);
- return PTR_ERR(sdesc);
- }
-
- ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest);
- kzfree(sdesc);
- return ret;
-}
-
-static int TSS_rawhmac(unsigned char *digest, const unsigned char *key,
- unsigned int keylen, ...)
-{
- struct sdesc *sdesc;
- va_list argp;
- unsigned int dlen;
- unsigned char *data;
- int ret;
-
- sdesc = init_sdesc(hmacalg);
- if (IS_ERR(sdesc)) {
- pr_info("trusted_key: can't alloc %s\n", hmac_alg);
- return PTR_ERR(sdesc);
- }
-
- ret = crypto_shash_setkey(hmacalg, key, keylen);
- if (ret < 0)
- goto out;
- ret = crypto_shash_init(&sdesc->shash);
- if (ret < 0)
- goto out;
-
- va_start(argp, keylen);
- for (;;) {
- dlen = va_arg(argp, unsigned int);
- if (dlen == 0)
- break;
- data = va_arg(argp, unsigned char *);
- if (data == NULL) {
- ret = -EINVAL;
- break;
- }
- ret = crypto_shash_update(&sdesc->shash, data, dlen);
- if (ret < 0)
- break;
- }
- va_end(argp);
- if (!ret)
- ret = crypto_shash_final(&sdesc->shash, digest);
-out:
- kzfree(sdesc);
- return ret;
-}
-
-/*
- * calculate authorization info fields to send to TPM
- */
-int TSS_authhmac(unsigned char *digest, const unsigned char *key,
- unsigned int keylen, unsigned char *h1,
- unsigned char *h2, unsigned int h3, ...)
-{
- unsigned char paramdigest[SHA1_DIGEST_SIZE];
- struct sdesc *sdesc;
- unsigned int dlen;
- unsigned char *data;
- unsigned char c;
- int ret;
- va_list argp;
-
- if (!chip)
- return -ENODEV;
-
- sdesc = init_sdesc(hashalg);
- if (IS_ERR(sdesc)) {
- pr_info("trusted_key: can't alloc %s\n", hash_alg);
- return PTR_ERR(sdesc);
- }
-
- c = !!h3;
- ret = crypto_shash_init(&sdesc->shash);
- if (ret < 0)
- goto out;
- va_start(argp, h3);
- for (;;) {
- dlen = va_arg(argp, unsigned int);
- if (dlen == 0)
- break;
- data = va_arg(argp, unsigned char *);
- if (!data) {
- ret = -EINVAL;
- break;
- }
- ret = crypto_shash_update(&sdesc->shash, data, dlen);
- if (ret < 0)
- break;
- }
- va_end(argp);
- if (!ret)
- ret = crypto_shash_final(&sdesc->shash, paramdigest);
- if (!ret)
- ret = TSS_rawhmac(digest, key, keylen, SHA1_DIGEST_SIZE,
- paramdigest, TPM_NONCE_SIZE, h1,
- TPM_NONCE_SIZE, h2, 1, &c, 0, 0);
-out:
- kzfree(sdesc);
- return ret;
-}
-EXPORT_SYMBOL_GPL(TSS_authhmac);
-
-/*
- * verify the AUTH1_COMMAND (Seal) result from TPM
- */
-int TSS_checkhmac1(unsigned char *buffer,
- const uint32_t command,
- const unsigned char *ononce,
- const unsigned char *key,
- unsigned int keylen, ...)
-{
- uint32_t bufsize;
- uint16_t tag;
- uint32_t ordinal;
- uint32_t result;
- unsigned char *enonce;
- unsigned char *continueflag;
- unsigned char *authdata;
- unsigned char testhmac[SHA1_DIGEST_SIZE];
- unsigned char paramdigest[SHA1_DIGEST_SIZE];
- struct sdesc *sdesc;
- unsigned int dlen;
- unsigned int dpos;
- va_list argp;
- int ret;
-
- if (!chip)
- return -ENODEV;
-
- bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
- tag = LOAD16(buffer, 0);
- ordinal = command;
- result = LOAD32N(buffer, TPM_RETURN_OFFSET);
- if (tag == TPM_TAG_RSP_COMMAND)
- return 0;
- if (tag != TPM_TAG_RSP_AUTH1_COMMAND)
- return -EINVAL;
- authdata = buffer + bufsize - SHA1_DIGEST_SIZE;
- continueflag = authdata - 1;
- enonce = continueflag - TPM_NONCE_SIZE;
-
- sdesc = init_sdesc(hashalg);
- if (IS_ERR(sdesc)) {
- pr_info("trusted_key: can't alloc %s\n", hash_alg);
- return PTR_ERR(sdesc);
- }
- ret = crypto_shash_init(&sdesc->shash);
- if (ret < 0)
- goto out;
- ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
- sizeof result);
- if (ret < 0)
- goto out;
- ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
- sizeof ordinal);
- if (ret < 0)
- goto out;
- va_start(argp, keylen);
- for (;;) {
- dlen = va_arg(argp, unsigned int);
- if (dlen == 0)
- break;
- dpos = va_arg(argp, unsigned int);
- ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
- if (ret < 0)
- break;
- }
- va_end(argp);
- if (!ret)
- ret = crypto_shash_final(&sdesc->shash, paramdigest);
- if (ret < 0)
- goto out;
-
- ret = TSS_rawhmac(testhmac, key, keylen, SHA1_DIGEST_SIZE, paramdigest,
- TPM_NONCE_SIZE, enonce, TPM_NONCE_SIZE, ononce,
- 1, continueflag, 0, 0);
- if (ret < 0)
- goto out;
-
- if (memcmp(testhmac, authdata, SHA1_DIGEST_SIZE))
- ret = -EINVAL;
-out:
- kzfree(sdesc);
- return ret;
-}
-EXPORT_SYMBOL_GPL(TSS_checkhmac1);
-
-/*
- * verify the AUTH2_COMMAND (unseal) result from TPM
- */
-static int TSS_checkhmac2(unsigned char *buffer,
- const uint32_t command,
- const unsigned char *ononce,
- const unsigned char *key1,
- unsigned int keylen1,
- const unsigned char *key2,
- unsigned int keylen2, ...)
-{
- uint32_t bufsize;
- uint16_t tag;
- uint32_t ordinal;
- uint32_t result;
- unsigned char *enonce1;
- unsigned char *continueflag1;
- unsigned char *authdata1;
- unsigned char *enonce2;
- unsigned char *continueflag2;
- unsigned char *authdata2;
- unsigned char testhmac1[SHA1_DIGEST_SIZE];
- unsigned char testhmac2[SHA1_DIGEST_SIZE];
- unsigned char paramdigest[SHA1_DIGEST_SIZE];
- struct sdesc *sdesc;
- unsigned int dlen;
- unsigned int dpos;
- va_list argp;
- int ret;
-
- bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
- tag = LOAD16(buffer, 0);
- ordinal = command;
- result = LOAD32N(buffer, TPM_RETURN_OFFSET);
-
- if (tag == TPM_TAG_RSP_COMMAND)
- return 0;
- if (tag != TPM_TAG_RSP_AUTH2_COMMAND)
- return -EINVAL;
- authdata1 = buffer + bufsize - (SHA1_DIGEST_SIZE + 1
- + SHA1_DIGEST_SIZE + SHA1_DIGEST_SIZE);
- authdata2 = buffer + bufsize - (SHA1_DIGEST_SIZE);
- continueflag1 = authdata1 - 1;
- continueflag2 = authdata2 - 1;
- enonce1 = continueflag1 - TPM_NONCE_SIZE;
- enonce2 = continueflag2 - TPM_NONCE_SIZE;
-
- sdesc = init_sdesc(hashalg);
- if (IS_ERR(sdesc)) {
- pr_info("trusted_key: can't alloc %s\n", hash_alg);
- return PTR_ERR(sdesc);
- }
- ret = crypto_shash_init(&sdesc->shash);
- if (ret < 0)
- goto out;
- ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
- sizeof result);
- if (ret < 0)
- goto out;
- ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
- sizeof ordinal);
- if (ret < 0)
- goto out;
-
- va_start(argp, keylen2);
- for (;;) {
- dlen = va_arg(argp, unsigned int);
- if (dlen == 0)
- break;
- dpos = va_arg(argp, unsigned int);
- ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
- if (ret < 0)
- break;
- }
- va_end(argp);
- if (!ret)
- ret = crypto_shash_final(&sdesc->shash, paramdigest);
- if (ret < 0)
- goto out;
-
- ret = TSS_rawhmac(testhmac1, key1, keylen1, SHA1_DIGEST_SIZE,
- paramdigest, TPM_NONCE_SIZE, enonce1,
- TPM_NONCE_SIZE, ononce, 1, continueflag1, 0, 0);
- if (ret < 0)
- goto out;
- if (memcmp(testhmac1, authdata1, SHA1_DIGEST_SIZE)) {
- ret = -EINVAL;
- goto out;
- }
- ret = TSS_rawhmac(testhmac2, key2, keylen2, SHA1_DIGEST_SIZE,
- paramdigest, TPM_NONCE_SIZE, enonce2,
- TPM_NONCE_SIZE, ononce, 1, continueflag2, 0, 0);
- if (ret < 0)
- goto out;
- if (memcmp(testhmac2, authdata2, SHA1_DIGEST_SIZE))
- ret = -EINVAL;
-out:
- kzfree(sdesc);
- return ret;
-}
-
-/*
- * For key specific tpm requests, we will generate and send our
- * own TPM command packets using the drivers send function.
- */
-int trusted_tpm_send(unsigned char *cmd, size_t buflen)
-{
- int rc;
-
- if (!chip)
- return -ENODEV;
-
- dump_tpm_buf(cmd);
- rc = tpm_send(chip, cmd, buflen);
- dump_tpm_buf(cmd);
- if (rc > 0)
- /* Can't return positive return codes values to keyctl */
- rc = -EPERM;
- return rc;
-}
-EXPORT_SYMBOL_GPL(trusted_tpm_send);
-
-/*
- * Lock a trusted key, by extending a selected PCR.
- *
- * Prevents a trusted key that is sealed to PCRs from being accessed.
- * This uses the tpm driver's extend function.
- */
-static int pcrlock(const int pcrnum)
-{
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
-
- return tpm_pcr_extend(chip, pcrnum, digests) ? -EINVAL : 0;
-}
-
-/*
- * Create an object specific authorisation protocol (OSAP) session
- */
-static int osap(struct tpm_buf *tb, struct osapsess *s,
- const unsigned char *key, uint16_t type, uint32_t handle)
-{
- unsigned char enonce[TPM_NONCE_SIZE];
- unsigned char ononce[TPM_NONCE_SIZE];
- int ret;
-
- ret = tpm_get_random(chip, ononce, TPM_NONCE_SIZE);
- if (ret != TPM_NONCE_SIZE)
- return ret;
-
- tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OSAP);
- tpm_buf_append_u16(tb, type);
- tpm_buf_append_u32(tb, handle);
- tpm_buf_append(tb, ononce, TPM_NONCE_SIZE);
-
- ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
- if (ret < 0)
- return ret;
-
- s->handle = LOAD32(tb->data, TPM_DATA_OFFSET);
- memcpy(s->enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)]),
- TPM_NONCE_SIZE);
- memcpy(enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t) +
- TPM_NONCE_SIZE]), TPM_NONCE_SIZE);
- return TSS_rawhmac(s->secret, key, SHA1_DIGEST_SIZE, TPM_NONCE_SIZE,
- enonce, TPM_NONCE_SIZE, ononce, 0, 0);
-}
-
-/*
- * Create an object independent authorisation protocol (oiap) session
- */
-int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce)
-{
- int ret;
-
- if (!chip)
- return -ENODEV;
-
- tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OIAP);
- ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
- if (ret < 0)
- return ret;
-
- *handle = LOAD32(tb->data, TPM_DATA_OFFSET);
- memcpy(nonce, &tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)],
- TPM_NONCE_SIZE);
- return 0;
-}
-EXPORT_SYMBOL_GPL(oiap);
-
-struct tpm_digests {
- unsigned char encauth[SHA1_DIGEST_SIZE];
- unsigned char pubauth[SHA1_DIGEST_SIZE];
- unsigned char xorwork[SHA1_DIGEST_SIZE * 2];
- unsigned char xorhash[SHA1_DIGEST_SIZE];
- unsigned char nonceodd[TPM_NONCE_SIZE];
-};
-
-/*
- * Have the TPM seal(encrypt) the trusted key, possibly based on
- * Platform Configuration Registers (PCRs). AUTH1 for sealing key.
- */
-static int tpm_seal(struct tpm_buf *tb, uint16_t keytype,
- uint32_t keyhandle, const unsigned char *keyauth,
- const unsigned char *data, uint32_t datalen,
- unsigned char *blob, uint32_t *bloblen,
- const unsigned char *blobauth,
- const unsigned char *pcrinfo, uint32_t pcrinfosize)
-{
- struct osapsess sess;
- struct tpm_digests *td;
- unsigned char cont;
- uint32_t ordinal;
- uint32_t pcrsize;
- uint32_t datsize;
- int sealinfosize;
- int encdatasize;
- int storedsize;
- int ret;
- int i;
-
- /* alloc some work space for all the hashes */
- td = kmalloc(sizeof *td, GFP_KERNEL);
- if (!td)
- return -ENOMEM;
-
- /* get session for sealing key */
- ret = osap(tb, &sess, keyauth, keytype, keyhandle);
- if (ret < 0)
- goto out;
- dump_sess(&sess);
-
- /* calculate encrypted authorization value */
- memcpy(td->xorwork, sess.secret, SHA1_DIGEST_SIZE);
- memcpy(td->xorwork + SHA1_DIGEST_SIZE, sess.enonce, SHA1_DIGEST_SIZE);
- ret = TSS_sha1(td->xorwork, SHA1_DIGEST_SIZE * 2, td->xorhash);
- if (ret < 0)
- goto out;
-
- ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE);
- if (ret != TPM_NONCE_SIZE)
- goto out;
- ordinal = htonl(TPM_ORD_SEAL);
- datsize = htonl(datalen);
- pcrsize = htonl(pcrinfosize);
- cont = 0;
-
- /* encrypt data authorization key */
- for (i = 0; i < SHA1_DIGEST_SIZE; ++i)
- td->encauth[i] = td->xorhash[i] ^ blobauth[i];
-
- /* calculate authorization HMAC value */
- if (pcrinfosize == 0) {
- /* no pcr info specified */
- ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
- sess.enonce, td->nonceodd, cont,
- sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
- td->encauth, sizeof(uint32_t), &pcrsize,
- sizeof(uint32_t), &datsize, datalen, data, 0,
- 0);
- } else {
- /* pcr info specified */
- ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
- sess.enonce, td->nonceodd, cont,
- sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
- td->encauth, sizeof(uint32_t), &pcrsize,
- pcrinfosize, pcrinfo, sizeof(uint32_t),
- &datsize, datalen, data, 0, 0);
- }
- if (ret < 0)
- goto out;
-
- /* build and send the TPM request packet */
- tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_SEAL);
- tpm_buf_append_u32(tb, keyhandle);
- tpm_buf_append(tb, td->encauth, SHA1_DIGEST_SIZE);
- tpm_buf_append_u32(tb, pcrinfosize);
- tpm_buf_append(tb, pcrinfo, pcrinfosize);
- tpm_buf_append_u32(tb, datalen);
- tpm_buf_append(tb, data, datalen);
- tpm_buf_append_u32(tb, sess.handle);
- tpm_buf_append(tb, td->nonceodd, TPM_NONCE_SIZE);
- tpm_buf_append_u8(tb, cont);
- tpm_buf_append(tb, td->pubauth, SHA1_DIGEST_SIZE);
-
- ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
- if (ret < 0)
- goto out;
-
- /* calculate the size of the returned Blob */
- sealinfosize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t));
- encdatasize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t) +
- sizeof(uint32_t) + sealinfosize);
- storedsize = sizeof(uint32_t) + sizeof(uint32_t) + sealinfosize +
- sizeof(uint32_t) + encdatasize;
-
- /* check the HMAC in the response */
- ret = TSS_checkhmac1(tb->data, ordinal, td->nonceodd, sess.secret,
- SHA1_DIGEST_SIZE, storedsize, TPM_DATA_OFFSET, 0,
- 0);
-
- /* copy the returned blob to caller */
- if (!ret) {
- memcpy(blob, tb->data + TPM_DATA_OFFSET, storedsize);
- *bloblen = storedsize;
- }
-out:
- kzfree(td);
- return ret;
-}
-
-/*
- * use the AUTH2_COMMAND form of unseal, to authorize both key and blob
- */
-static int tpm_unseal(struct tpm_buf *tb,
- uint32_t keyhandle, const unsigned char *keyauth,
- const unsigned char *blob, int bloblen,
- const unsigned char *blobauth,
- unsigned char *data, unsigned int *datalen)
-{
- unsigned char nonceodd[TPM_NONCE_SIZE];
- unsigned char enonce1[TPM_NONCE_SIZE];
- unsigned char enonce2[TPM_NONCE_SIZE];
- unsigned char authdata1[SHA1_DIGEST_SIZE];
- unsigned char authdata2[SHA1_DIGEST_SIZE];
- uint32_t authhandle1 = 0;
- uint32_t authhandle2 = 0;
- unsigned char cont = 0;
- uint32_t ordinal;
- uint32_t keyhndl;
- int ret;
-
- /* sessions for unsealing key and data */
- ret = oiap(tb, &authhandle1, enonce1);
- if (ret < 0) {
- pr_info("trusted_key: oiap failed (%d)\n", ret);
- return ret;
- }
- ret = oiap(tb, &authhandle2, enonce2);
- if (ret < 0) {
- pr_info("trusted_key: oiap failed (%d)\n", ret);
- return ret;
- }
-
- ordinal = htonl(TPM_ORD_UNSEAL);
- keyhndl = htonl(SRKHANDLE);
- ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE);
- if (ret != TPM_NONCE_SIZE) {
- pr_info("trusted_key: tpm_get_random failed (%d)\n", ret);
- return ret;
- }
- ret = TSS_authhmac(authdata1, keyauth, TPM_NONCE_SIZE,
- enonce1, nonceodd, cont, sizeof(uint32_t),
- &ordinal, bloblen, blob, 0, 0);
- if (ret < 0)
- return ret;
- ret = TSS_authhmac(authdata2, blobauth, TPM_NONCE_SIZE,
- enonce2, nonceodd, cont, sizeof(uint32_t),
- &ordinal, bloblen, blob, 0, 0);
- if (ret < 0)
- return ret;
-
- /* build and send TPM request packet */
- tpm_buf_reset(tb, TPM_TAG_RQU_AUTH2_COMMAND, TPM_ORD_UNSEAL);
- tpm_buf_append_u32(tb, keyhandle);
- tpm_buf_append(tb, blob, bloblen);
- tpm_buf_append_u32(tb, authhandle1);
- tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE);
- tpm_buf_append_u8(tb, cont);
- tpm_buf_append(tb, authdata1, SHA1_DIGEST_SIZE);
- tpm_buf_append_u32(tb, authhandle2);
- tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE);
- tpm_buf_append_u8(tb, cont);
- tpm_buf_append(tb, authdata2, SHA1_DIGEST_SIZE);
-
- ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
- if (ret < 0) {
- pr_info("trusted_key: authhmac failed (%d)\n", ret);
- return ret;
- }
-
- *datalen = LOAD32(tb->data, TPM_DATA_OFFSET);
- ret = TSS_checkhmac2(tb->data, ordinal, nonceodd,
- keyauth, SHA1_DIGEST_SIZE,
- blobauth, SHA1_DIGEST_SIZE,
- sizeof(uint32_t), TPM_DATA_OFFSET,
- *datalen, TPM_DATA_OFFSET + sizeof(uint32_t), 0,
- 0);
- if (ret < 0) {
- pr_info("trusted_key: TSS_checkhmac2 failed (%d)\n", ret);
- return ret;
- }
- memcpy(data, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), *datalen);
- return 0;
-}
-
-/*
- * Have the TPM seal(encrypt) the symmetric key
- */
-static int key_seal(struct trusted_key_payload *p,
- struct trusted_key_options *o)
-{
- struct tpm_buf tb;
- int ret;
-
- ret = tpm_buf_init(&tb, 0, 0);
- if (ret)
- return ret;
-
- /* include migratable flag at end of sealed key */
- p->key[p->key_len] = p->migratable;
-
- ret = tpm_seal(&tb, o->keytype, o->keyhandle, o->keyauth,
- p->key, p->key_len + 1, p->blob, &p->blob_len,
- o->blobauth, o->pcrinfo, o->pcrinfo_len);
- if (ret < 0)
- pr_info("trusted_key: srkseal failed (%d)\n", ret);
-
- tpm_buf_destroy(&tb);
- return ret;
-}
-
-/*
- * Have the TPM unseal(decrypt) the symmetric key
- */
-static int key_unseal(struct trusted_key_payload *p,
- struct trusted_key_options *o)
-{
- struct tpm_buf tb;
- int ret;
-
- ret = tpm_buf_init(&tb, 0, 0);
- if (ret)
- return ret;
-
- ret = tpm_unseal(&tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
- o->blobauth, p->key, &p->key_len);
- if (ret < 0)
- pr_info("trusted_key: srkunseal failed (%d)\n", ret);
- else
- /* pull migratable flag out of sealed key */
- p->migratable = p->key[--p->key_len];
-
- tpm_buf_destroy(&tb);
- return ret;
-}
-
-enum {
- Opt_err,
- Opt_new, Opt_load, Opt_update,
- Opt_keyhandle, Opt_keyauth, Opt_blobauth,
- Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
- Opt_hash,
- Opt_policydigest,
- Opt_policyhandle,
-};
-
-static const match_table_t key_tokens = {
- {Opt_new, "new"},
- {Opt_load, "load"},
- {Opt_update, "update"},
- {Opt_keyhandle, "keyhandle=%s"},
- {Opt_keyauth, "keyauth=%s"},
- {Opt_blobauth, "blobauth=%s"},
- {Opt_pcrinfo, "pcrinfo=%s"},
- {Opt_pcrlock, "pcrlock=%s"},
- {Opt_migratable, "migratable=%s"},
- {Opt_hash, "hash=%s"},
- {Opt_policydigest, "policydigest=%s"},
- {Opt_policyhandle, "policyhandle=%s"},
- {Opt_err, NULL}
-};
-
-/* can have zero or more token= options */
-static int getoptions(char *c, struct trusted_key_payload *pay,
- struct trusted_key_options *opt)
-{
- substring_t args[MAX_OPT_ARGS];
- char *p = c;
- int token;
- int res;
- unsigned long handle;
- unsigned long lock;
- unsigned long token_mask = 0;
- unsigned int digest_len;
- int i;
- int tpm2;
-
- tpm2 = tpm_is_tpm2(chip);
- if (tpm2 < 0)
- return tpm2;
-
- opt->hash = tpm2 ? HASH_ALGO_SHA256 : HASH_ALGO_SHA1;
-
- while ((p = strsep(&c, " \t"))) {
- if (*p == '\0' || *p == ' ' || *p == '\t')
- continue;
- token = match_token(p, key_tokens, args);
- if (test_and_set_bit(token, &token_mask))
- return -EINVAL;
-
- switch (token) {
- case Opt_pcrinfo:
- opt->pcrinfo_len = strlen(args[0].from) / 2;
- if (opt->pcrinfo_len > MAX_PCRINFO_SIZE)
- return -EINVAL;
- res = hex2bin(opt->pcrinfo, args[0].from,
- opt->pcrinfo_len);
- if (res < 0)
- return -EINVAL;
- break;
- case Opt_keyhandle:
- res = kstrtoul(args[0].from, 16, &handle);
- if (res < 0)
- return -EINVAL;
- opt->keytype = SEAL_keytype;
- opt->keyhandle = handle;
- break;
- case Opt_keyauth:
- if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
- return -EINVAL;
- res = hex2bin(opt->keyauth, args[0].from,
- SHA1_DIGEST_SIZE);
- if (res < 0)
- return -EINVAL;
- break;
- case Opt_blobauth:
- if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
- return -EINVAL;
- res = hex2bin(opt->blobauth, args[0].from,
- SHA1_DIGEST_SIZE);
- if (res < 0)
- return -EINVAL;
- break;
- case Opt_migratable:
- if (*args[0].from == '0')
- pay->migratable = 0;
- else
- return -EINVAL;
- break;
- case Opt_pcrlock:
- res = kstrtoul(args[0].from, 10, &lock);
- if (res < 0)
- return -EINVAL;
- opt->pcrlock = lock;
- break;
- case Opt_hash:
- if (test_bit(Opt_policydigest, &token_mask))
- return -EINVAL;
- for (i = 0; i < HASH_ALGO__LAST; i++) {
- if (!strcmp(args[0].from, hash_algo_name[i])) {
- opt->hash = i;
- break;
- }
- }
- if (i == HASH_ALGO__LAST)
- return -EINVAL;
- if (!tpm2 && i != HASH_ALGO_SHA1) {
- pr_info("trusted_key: TPM 1.x only supports SHA-1.\n");
- return -EINVAL;
- }
- break;
- case Opt_policydigest:
- digest_len = hash_digest_size[opt->hash];
- if (!tpm2 || strlen(args[0].from) != (2 * digest_len))
- return -EINVAL;
- res = hex2bin(opt->policydigest, args[0].from,
- digest_len);
- if (res < 0)
- return -EINVAL;
- opt->policydigest_len = digest_len;
- break;
- case Opt_policyhandle:
- if (!tpm2)
- return -EINVAL;
- res = kstrtoul(args[0].from, 16, &handle);
- if (res < 0)
- return -EINVAL;
- opt->policyhandle = handle;
- break;
- default:
- return -EINVAL;
- }
- }
- return 0;
-}
-
-/*
- * datablob_parse - parse the keyctl data and fill in the
- * payload and options structures
- *
- * On success returns 0, otherwise -EINVAL.
- */
-static int datablob_parse(char *datablob, struct trusted_key_payload *p,
- struct trusted_key_options *o)
-{
- substring_t args[MAX_OPT_ARGS];
- long keylen;
- int ret = -EINVAL;
- int key_cmd;
- char *c;
-
- /* main command */
- c = strsep(&datablob, " \t");
- if (!c)
- return -EINVAL;
- key_cmd = match_token(c, key_tokens, args);
- switch (key_cmd) {
- case Opt_new:
- /* first argument is key size */
- c = strsep(&datablob, " \t");
- if (!c)
- return -EINVAL;
- ret = kstrtol(c, 10, &keylen);
- if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
- return -EINVAL;
- p->key_len = keylen;
- ret = getoptions(datablob, p, o);
- if (ret < 0)
- return ret;
- ret = Opt_new;
- break;
- case Opt_load:
- /* first argument is sealed blob */
- c = strsep(&datablob, " \t");
- if (!c)
- return -EINVAL;
- p->blob_len = strlen(c) / 2;
- if (p->blob_len > MAX_BLOB_SIZE)
- return -EINVAL;
- ret = hex2bin(p->blob, c, p->blob_len);
- if (ret < 0)
- return -EINVAL;
- ret = getoptions(datablob, p, o);
- if (ret < 0)
- return ret;
- ret = Opt_load;
- break;
- case Opt_update:
- /* all arguments are options */
- ret = getoptions(datablob, p, o);
- if (ret < 0)
- return ret;
- ret = Opt_update;
- break;
- case Opt_err:
- return -EINVAL;
- break;
- }
- return ret;
-}
-
-static struct trusted_key_options *trusted_options_alloc(void)
-{
- struct trusted_key_options *options;
- int tpm2;
-
- tpm2 = tpm_is_tpm2(chip);
- if (tpm2 < 0)
- return NULL;
-
- options = kzalloc(sizeof *options, GFP_KERNEL);
- if (options) {
- /* set any non-zero defaults */
- options->keytype = SRK_keytype;
-
- if (!tpm2)
- options->keyhandle = SRKHANDLE;
- }
- return options;
-}
-
-static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
-{
- struct trusted_key_payload *p = NULL;
- int ret;
-
- ret = key_payload_reserve(key, sizeof *p);
- if (ret < 0)
- return p;
- p = kzalloc(sizeof *p, GFP_KERNEL);
- if (p)
- p->migratable = 1; /* migratable by default */
- return p;
-}
-
-/*
- * trusted_instantiate - create a new trusted key
- *
- * Unseal an existing trusted blob or, for a new key, get a
- * random key, then seal and create a trusted key-type key,
- * adding it to the specified keyring.
- *
- * On success, return 0. Otherwise return errno.
- */
-static int trusted_instantiate(struct key *key,
- struct key_preparsed_payload *prep)
-{
- struct trusted_key_payload *payload = NULL;
- struct trusted_key_options *options = NULL;
- size_t datalen = prep->datalen;
- char *datablob;
- int ret = 0;
- int key_cmd;
- size_t key_len;
- int tpm2;
-
- tpm2 = tpm_is_tpm2(chip);
- if (tpm2 < 0)
- return tpm2;
-
- if (datalen <= 0 || datalen > 32767 || !prep->data)
- return -EINVAL;
-
- datablob = kmalloc(datalen + 1, GFP_KERNEL);
- if (!datablob)
- return -ENOMEM;
- memcpy(datablob, prep->data, datalen);
- datablob[datalen] = '\0';
-
- options = trusted_options_alloc();
- if (!options) {
- ret = -ENOMEM;
- goto out;
- }
- payload = trusted_payload_alloc(key);
- if (!payload) {
- ret = -ENOMEM;
- goto out;
- }
-
- key_cmd = datablob_parse(datablob, payload, options);
- if (key_cmd < 0) {
- ret = key_cmd;
- goto out;
- }
-
- if (!options->keyhandle) {
- ret = -EINVAL;
- goto out;
- }
-
- dump_payload(payload);
- dump_options(options);
-
- switch (key_cmd) {
- case Opt_load:
- if (tpm2)
- ret = tpm_unseal_trusted(chip, payload, options);
- else
- ret = key_unseal(payload, options);
- dump_payload(payload);
- dump_options(options);
- if (ret < 0)
- pr_info("trusted_key: key_unseal failed (%d)\n", ret);
- break;
- case Opt_new:
- key_len = payload->key_len;
- ret = tpm_get_random(chip, payload->key, key_len);
- if (ret != key_len) {
- pr_info("trusted_key: key_create failed (%d)\n", ret);
- goto out;
- }
- if (tpm2)
- ret = tpm_seal_trusted(chip, payload, options);
- else
- ret = key_seal(payload, options);
- if (ret < 0)
- pr_info("trusted_key: key_seal failed (%d)\n", ret);
- break;
- default:
- ret = -EINVAL;
- goto out;
- }
- if (!ret && options->pcrlock)
- ret = pcrlock(options->pcrlock);
-out:
- kzfree(datablob);
- kzfree(options);
- if (!ret)
- rcu_assign_keypointer(key, payload);
- else
- kzfree(payload);
- return ret;
-}
-
-static void trusted_rcu_free(struct rcu_head *rcu)
-{
- struct trusted_key_payload *p;
-
- p = container_of(rcu, struct trusted_key_payload, rcu);
- kzfree(p);
-}
-
-/*
- * trusted_update - reseal an existing key with new PCR values
- */
-static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
-{
- struct trusted_key_payload *p;
- struct trusted_key_payload *new_p;
- struct trusted_key_options *new_o;
- size_t datalen = prep->datalen;
- char *datablob;
- int ret = 0;
-
- if (key_is_negative(key))
- return -ENOKEY;
- p = key->payload.data[0];
- if (!p->migratable)
- return -EPERM;
- if (datalen <= 0 || datalen > 32767 || !prep->data)
- return -EINVAL;
-
- datablob = kmalloc(datalen + 1, GFP_KERNEL);
- if (!datablob)
- return -ENOMEM;
- new_o = trusted_options_alloc();
- if (!new_o) {
- ret = -ENOMEM;
- goto out;
- }
- new_p = trusted_payload_alloc(key);
- if (!new_p) {
- ret = -ENOMEM;
- goto out;
- }
-
- memcpy(datablob, prep->data, datalen);
- datablob[datalen] = '\0';
- ret = datablob_parse(datablob, new_p, new_o);
- if (ret != Opt_update) {
- ret = -EINVAL;
- kzfree(new_p);
- goto out;
- }
-
- if (!new_o->keyhandle) {
- ret = -EINVAL;
- kzfree(new_p);
- goto out;
- }
-
- /* copy old key values, and reseal with new pcrs */
- new_p->migratable = p->migratable;
- new_p->key_len = p->key_len;
- memcpy(new_p->key, p->key, p->key_len);
- dump_payload(p);
- dump_payload(new_p);
-
- ret = key_seal(new_p, new_o);
- if (ret < 0) {
- pr_info("trusted_key: key_seal failed (%d)\n", ret);
- kzfree(new_p);
- goto out;
- }
- if (new_o->pcrlock) {
- ret = pcrlock(new_o->pcrlock);
- if (ret < 0) {
- pr_info("trusted_key: pcrlock failed (%d)\n", ret);
- kzfree(new_p);
- goto out;
- }
- }
- rcu_assign_keypointer(key, new_p);
- call_rcu(&p->rcu, trusted_rcu_free);
-out:
- kzfree(datablob);
- kzfree(new_o);
- return ret;
-}
-
-/*
- * trusted_read - copy the sealed blob data to userspace in hex.
- * On success, return to userspace the trusted key datablob size.
- */
-static long trusted_read(const struct key *key, char __user *buffer,
- size_t buflen)
-{
- const struct trusted_key_payload *p;
- char *ascii_buf;
- char *bufp;
- int i;
-
- p = dereference_key_locked(key);
- if (!p)
- return -EINVAL;
-
- if (buffer && buflen >= 2 * p->blob_len) {
- ascii_buf = kmalloc_array(2, p->blob_len, GFP_KERNEL);
- if (!ascii_buf)
- return -ENOMEM;
-
- bufp = ascii_buf;
- for (i = 0; i < p->blob_len; i++)
- bufp = hex_byte_pack(bufp, p->blob[i]);
- if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) {
- kzfree(ascii_buf);
- return -EFAULT;
- }
- kzfree(ascii_buf);
- }
- return 2 * p->blob_len;
-}
-
-/*
- * trusted_destroy - clear and free the key's payload
- */
-static void trusted_destroy(struct key *key)
-{
- kzfree(key->payload.data[0]);
-}
-
-struct key_type key_type_trusted = {
- .name = "trusted",
- .instantiate = trusted_instantiate,
- .update = trusted_update,
- .destroy = trusted_destroy,
- .describe = user_describe,
- .read = trusted_read,
-};
-
-EXPORT_SYMBOL_GPL(key_type_trusted);
-
-static void trusted_shash_release(void)
-{
- if (hashalg)
- crypto_free_shash(hashalg);
- if (hmacalg)
- crypto_free_shash(hmacalg);
-}
-
-static int __init trusted_shash_alloc(void)
-{
- int ret;
-
- hmacalg = crypto_alloc_shash(hmac_alg, 0, 0);
- if (IS_ERR(hmacalg)) {
- pr_info("trusted_key: could not allocate crypto %s\n",
- hmac_alg);
- return PTR_ERR(hmacalg);
- }
-
- hashalg = crypto_alloc_shash(hash_alg, 0, 0);
- if (IS_ERR(hashalg)) {
- pr_info("trusted_key: could not allocate crypto %s\n",
- hash_alg);
- ret = PTR_ERR(hashalg);
- goto hashalg_fail;
- }
-
- return 0;
-
-hashalg_fail:
- crypto_free_shash(hmacalg);
- return ret;
-}
-
-static int __init init_digests(void)
-{
- int i;
-
- digests = kcalloc(chip->nr_allocated_banks, sizeof(*digests),
- GFP_KERNEL);
- if (!digests)
- return -ENOMEM;
-
- for (i = 0; i < chip->nr_allocated_banks; i++)
- digests[i].alg_id = chip->allocated_banks[i].alg_id;
-
- return 0;
-}
-
-static int __init init_trusted(void)
-{
- int ret;
-
- /* encrypted_keys.ko depends on successful load of this module even if
- * TPM is not used.
- */
- chip = tpm_default_chip();
- if (!chip)
- return 0;
-
- ret = init_digests();
- if (ret < 0)
- goto err_put;
- ret = trusted_shash_alloc();
- if (ret < 0)
- goto err_free;
- ret = register_key_type(&key_type_trusted);
- if (ret < 0)
- goto err_release;
- return 0;
-err_release:
- trusted_shash_release();
-err_free:
- kfree(digests);
-err_put:
- put_device(&chip->dev);
- return ret;
-}
-
-static void __exit cleanup_trusted(void)
-{
- if (chip) {
- put_device(&chip->dev);
- kfree(digests);
- trusted_shash_release();
- unregister_key_type(&key_type_trusted);
- }
-}
-
-late_initcall(init_trusted);
-module_exit(cleanup_trusted);
-
-MODULE_LICENSE("GPL");
git.samba.org / sfrench / cifs-2.6.git / blobdiff