diff options
Diffstat (limited to 'security/keys')
28 files changed, 1828 insertions, 959 deletions
diff --git a/security/keys/Kconfig b/security/keys/Kconfig index 47c041563d41..abb03a1b2a5c 100644 --- a/security/keys/Kconfig +++ b/security/keys/Kconfig @@ -60,9 +60,7 @@ config BIG_KEYS bool "Large payload keys" depends on KEYS depends on TMPFS - select CRYPTO - select CRYPTO_AES - select CRYPTO_GCM + depends on CRYPTO_LIB_CHACHA20POLY1305 = y help This option provides support for holding large keys within the kernel (for example Kerberos ticket caches). The data may be stored out to @@ -72,20 +70,19 @@ config BIG_KEYS config TRUSTED_KEYS tristate "TRUSTED KEYS" - depends on KEYS && TCG_TPM - select CRYPTO - select CRYPTO_HMAC - select CRYPTO_SHA1 - select CRYPTO_HASH_INFO + depends on KEYS help This option provides support for creating, sealing, and unsealing keys in the kernel. Trusted keys are random number symmetric keys, - generated and RSA-sealed by the TPM. The TPM only unseals the keys, - if the boot PCRs and other criteria match. Userspace will only ever - see encrypted blobs. + generated and sealed by a trust source selected at kernel boot-time. + Userspace will only ever see encrypted blobs. If you are unsure as to whether this is required, answer N. +if TRUSTED_KEYS +source "security/keys/trusted-keys/Kconfig" +endif + config ENCRYPTED_KEYS tristate "ENCRYPTED KEYS" depends on KEYS @@ -97,10 +94,21 @@ config ENCRYPTED_KEYS select CRYPTO_RNG help This option provides support for create/encrypting/decrypting keys - in the kernel. Encrypted keys are kernel generated random numbers, - which are encrypted/decrypted with a 'master' symmetric key. The - 'master' key can be either a trusted-key or user-key type. - Userspace only ever sees/stores encrypted blobs. + in the kernel. Encrypted keys are instantiated using kernel + generated random numbers or provided decrypted data, and are + encrypted/decrypted with a 'master' symmetric key. The 'master' + key can be either a trusted-key or user-key type. Only encrypted + blobs are ever output to Userspace. + + If you are unsure as to whether this is required, answer N. + +config USER_DECRYPTED_DATA + bool "Allow encrypted keys with user decrypted data" + depends on ENCRYPTED_KEYS + help + This option provides support for instantiating encrypted keys using + user-provided decrypted data. The decrypted data must be hex-ascii + encoded. If you are unsure as to whether this is required, answer N. @@ -108,7 +116,7 @@ config KEY_DH_OPERATIONS bool "Diffie-Hellman operations on retained keys" depends on KEYS select CRYPTO - select CRYPTO_HASH + select CRYPTO_KDF800108_CTR select CRYPTO_DH help This option provides support for calculating Diffie-Hellman @@ -116,3 +124,12 @@ config KEY_DH_OPERATIONS in the kernel. If you are unsure as to whether this is required, answer N. + +config KEY_NOTIFICATIONS + bool "Provide key/keyring change notifications" + depends on KEYS && WATCH_QUEUE + help + This option provides support for getting change notifications + on keys and keyrings on which the caller has View permission. + This makes use of pipes to handle the notification buffer and + provides KEYCTL_WATCH_KEY to enable/disable watches. diff --git a/security/keys/big_key.c b/security/keys/big_key.c index 001abe530a0d..c3367622c683 100644 --- a/security/keys/big_key.c +++ b/security/keys/big_key.c @@ -1,7 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-or-later /* Large capacity key type * - * Copyright (C) 2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. + * Copyright (C) 2017-2020 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) */ @@ -12,38 +12,21 @@ #include <linux/file.h> #include <linux/shmem_fs.h> #include <linux/err.h> -#include <linux/scatterlist.h> #include <linux/random.h> -#include <linux/vmalloc.h> #include <keys/user-type.h> #include <keys/big_key-type.h> -#include <crypto/aead.h> -#include <crypto/gcm.h> - -struct big_key_buf { - unsigned int nr_pages; - void *virt; - struct scatterlist *sg; - struct page *pages[]; -}; +#include <crypto/chacha20poly1305.h> /* * Layout of key payload words. */ -enum { - big_key_data, - big_key_path, - big_key_path_2nd_part, - big_key_len, -}; - -/* - * Crypto operation with big_key data - */ -enum big_key_op { - BIG_KEY_ENC, - BIG_KEY_DEC, +struct big_key_payload { + u8 *data; + struct path path; + size_t length; }; +#define to_big_key_payload(payload) \ + (struct big_key_payload *)((payload).data) /* * If the data is under this limit, there's no point creating a shm file to @@ -53,16 +36,6 @@ enum big_key_op { #define BIG_KEY_FILE_THRESHOLD (sizeof(struct inode) + sizeof(struct dentry)) /* - * Key size for big_key data encryption - */ -#define ENC_KEY_SIZE 32 - -/* - * Authentication tag length - */ -#define ENC_AUTHTAG_SIZE 16 - -/* * big_key defined keys take an arbitrary string as the description and an * arbitrary blob of data as the payload */ @@ -75,173 +48,59 @@ struct key_type key_type_big_key = { .destroy = big_key_destroy, .describe = big_key_describe, .read = big_key_read, - /* no ->update(); don't add it without changing big_key_crypt() nonce */ + .update = big_key_update, }; /* - * Crypto names for big_key data authenticated encryption - */ -static const char big_key_alg_name[] = "gcm(aes)"; -#define BIG_KEY_IV_SIZE GCM_AES_IV_SIZE - -/* - * Crypto algorithms for big_key data authenticated encryption - */ -static struct crypto_aead *big_key_aead; - -/* - * Since changing the key affects the entire object, we need a mutex. - */ -static DEFINE_MUTEX(big_key_aead_lock); - -/* - * Encrypt/decrypt big_key data - */ -static int big_key_crypt(enum big_key_op op, struct big_key_buf *buf, size_t datalen, u8 *key) -{ - int ret; - struct aead_request *aead_req; - /* We always use a zero nonce. The reason we can get away with this is - * because we're using a different randomly generated key for every - * different encryption. Notably, too, key_type_big_key doesn't define - * an .update function, so there's no chance we'll wind up reusing the - * key to encrypt updated data. Simply put: one key, one encryption. - */ - u8 zero_nonce[BIG_KEY_IV_SIZE]; - - aead_req = aead_request_alloc(big_key_aead, GFP_KERNEL); - if (!aead_req) - return -ENOMEM; - - memset(zero_nonce, 0, sizeof(zero_nonce)); - aead_request_set_crypt(aead_req, buf->sg, buf->sg, datalen, zero_nonce); - aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL); - aead_request_set_ad(aead_req, 0); - - mutex_lock(&big_key_aead_lock); - if (crypto_aead_setkey(big_key_aead, key, ENC_KEY_SIZE)) { - ret = -EAGAIN; - goto error; - } - if (op == BIG_KEY_ENC) - ret = crypto_aead_encrypt(aead_req); - else - ret = crypto_aead_decrypt(aead_req); -error: - mutex_unlock(&big_key_aead_lock); - aead_request_free(aead_req); - return ret; -} - -/* - * Free up the buffer. - */ -static void big_key_free_buffer(struct big_key_buf *buf) -{ - unsigned int i; - - if (buf->virt) { - memset(buf->virt, 0, buf->nr_pages * PAGE_SIZE); - vunmap(buf->virt); - } - - for (i = 0; i < buf->nr_pages; i++) - if (buf->pages[i]) - __free_page(buf->pages[i]); - - kfree(buf); -} - -/* - * Allocate a buffer consisting of a set of pages with a virtual mapping - * applied over them. - */ -static void *big_key_alloc_buffer(size_t len) -{ - struct big_key_buf *buf; - unsigned int npg = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; - unsigned int i, l; - - buf = kzalloc(sizeof(struct big_key_buf) + - sizeof(struct page) * npg + - sizeof(struct scatterlist) * npg, - GFP_KERNEL); - if (!buf) - return NULL; - - buf->nr_pages = npg; - buf->sg = (void *)(buf->pages + npg); - sg_init_table(buf->sg, npg); - - for (i = 0; i < buf->nr_pages; i++) { - buf->pages[i] = alloc_page(GFP_KERNEL); - if (!buf->pages[i]) - goto nomem; - - l = min_t(size_t, len, PAGE_SIZE); - sg_set_page(&buf->sg[i], buf->pages[i], l, 0); - len -= l; - } - - buf->virt = vmap(buf->pages, buf->nr_pages, VM_MAP, PAGE_KERNEL); - if (!buf->virt) - goto nomem; - - return buf; - -nomem: - big_key_free_buffer(buf); - return NULL; -} - -/* * Preparse a big key */ int big_key_preparse(struct key_preparsed_payload *prep) { - struct big_key_buf *buf; - struct path *path = (struct path *)&prep->payload.data[big_key_path]; + struct big_key_payload *payload = to_big_key_payload(prep->payload); struct file *file; - u8 *enckey; + u8 *buf, *enckey; ssize_t written; - size_t datalen = prep->datalen, enclen = datalen + ENC_AUTHTAG_SIZE; + size_t datalen = prep->datalen; + size_t enclen = datalen + CHACHA20POLY1305_AUTHTAG_SIZE; int ret; + BUILD_BUG_ON(sizeof(*payload) != sizeof(prep->payload.data)); + if (datalen <= 0 || datalen > 1024 * 1024 || !prep->data) return -EINVAL; /* Set an arbitrary quota */ prep->quotalen = 16; - prep->payload.data[big_key_len] = (void *)(unsigned long)datalen; + payload->length = datalen; if (datalen > BIG_KEY_FILE_THRESHOLD) { /* Create a shmem file to store the data in. This will permit the data * to be swapped out if needed. * * File content is stored encrypted with randomly generated key. + * Since the key is random for each file, we can set the nonce + * to zero, provided we never define a ->update() call. */ loff_t pos = 0; - buf = big_key_alloc_buffer(enclen); + buf = kvmalloc(enclen, GFP_KERNEL); if (!buf) return -ENOMEM; - memcpy(buf->virt, prep->data, datalen); /* generate random key */ - enckey = kmalloc(ENC_KEY_SIZE, GFP_KERNEL); + enckey = kmalloc(CHACHA20POLY1305_KEY_SIZE, GFP_KERNEL); if (!enckey) { ret = -ENOMEM; goto error; } - ret = get_random_bytes_wait(enckey, ENC_KEY_SIZE); + ret = get_random_bytes_wait(enckey, CHACHA20POLY1305_KEY_SIZE); if (unlikely(ret)) goto err_enckey; - /* encrypt aligned data */ - ret = big_key_crypt(BIG_KEY_ENC, buf, datalen, enckey); - if (ret) - goto err_enckey; + /* encrypt data */ + chacha20poly1305_encrypt(buf, prep->data, datalen, NULL, 0, + 0, enckey); /* save aligned data to file */ file = shmem_kernel_file_setup("", enclen, 0); @@ -250,22 +109,22 @@ int big_key_preparse(struct key_preparsed_payload *prep) goto err_enckey; } - written = kernel_write(file, buf->virt, enclen, &pos); + written = kernel_write(file, buf, enclen, &pos); if (written != enclen) { ret = written; if (written >= 0) - ret = -ENOMEM; + ret = -EIO; goto err_fput; } /* Pin the mount and dentry to the key so that we can open it again * later */ - prep->payload.data[big_key_data] = enckey; - *path = file->f_path; - path_get(path); + payload->data = enckey; + payload->path = file->f_path; + path_get(&payload->path); fput(file); - big_key_free_buffer(buf); + kvfree_sensitive(buf, enclen); } else { /* Just store the data in a buffer */ void *data = kmalloc(datalen, GFP_KERNEL); @@ -273,7 +132,7 @@ int big_key_preparse(struct key_preparsed_payload *prep) if (!data) return -ENOMEM; - prep->payload.data[big_key_data] = data; + payload->data = data; memcpy(data, prep->data, prep->datalen); } return 0; @@ -281,9 +140,9 @@ int big_key_preparse(struct key_preparsed_payload *prep) err_fput: fput(file); err_enckey: - kzfree(enckey); + kfree_sensitive(enckey); error: - big_key_free_buffer(buf); + kvfree_sensitive(buf, enclen); return ret; } @@ -292,12 +151,11 @@ error: */ void big_key_free_preparse(struct key_preparsed_payload *prep) { - if (prep->datalen > BIG_KEY_FILE_THRESHOLD) { - struct path *path = (struct path *)&prep->payload.data[big_key_path]; + struct big_key_payload *payload = to_big_key_payload(prep->payload); - path_put(path); - } - kzfree(prep->payload.data[big_key_data]); + if (prep->datalen > BIG_KEY_FILE_THRESHOLD) + path_put(&payload->path); + kfree_sensitive(payload->data); } /* @@ -306,13 +164,12 @@ void big_key_free_preparse(struct key_preparsed_payload *prep) */ void big_key_revoke(struct key *key) { - struct path *path = (struct path *)&key->payload.data[big_key_path]; + struct big_key_payload *payload = to_big_key_payload(key->payload); /* clear the quota */ key_payload_reserve(key, 0); - if (key_is_positive(key) && - (size_t)key->payload.data[big_key_len] > BIG_KEY_FILE_THRESHOLD) - vfs_truncate(path, 0); + if (key_is_positive(key) && payload->length > BIG_KEY_FILE_THRESHOLD) + vfs_truncate(&payload->path, 0); } /* @@ -320,17 +177,32 @@ void big_key_revoke(struct key *key) */ void big_key_destroy(struct key *key) { - size_t datalen = (size_t)key->payload.data[big_key_len]; - - if (datalen > BIG_KEY_FILE_THRESHOLD) { - struct path *path = (struct path *)&key->payload.data[big_key_path]; + struct big_key_payload *payload = to_big_key_payload(key->payload); - path_put(path); - path->mnt = NULL; - path->dentry = NULL; + if (payload->length > BIG_KEY_FILE_THRESHOLD) { + path_put(&payload->path); + payload->path.mnt = NULL; + payload->path.dentry = NULL; } - kzfree(key->payload.data[big_key_data]); - key->payload.data[big_key_data] = NULL; + kfree_sensitive(payload->data); + payload->data = NULL; +} + +/* + * Update a big key + */ +int big_key_update(struct key *key, struct key_preparsed_payload *prep) +{ + int ret; + + ret = key_payload_reserve(key, prep->datalen); + if (ret < 0) + return ret; + + if (key_is_positive(key)) + big_key_destroy(key); + + return generic_key_instantiate(key, prep); } /* @@ -338,72 +210,70 @@ void big_key_destroy(struct key *key) */ void big_key_describe(const struct key *key, struct seq_file *m) { - size_t datalen = (size_t)key->payload.data[big_key_len]; + struct big_key_payload *payload = to_big_key_payload(key->payload); seq_puts(m, key->description); if (key_is_positive(key)) seq_printf(m, ": %zu [%s]", - datalen, - datalen > BIG_KEY_FILE_THRESHOLD ? "file" : "buff"); + payload->length, + payload->length > BIG_KEY_FILE_THRESHOLD ? "file" : "buff"); } /* * read the key data * - the key's semaphore is read-locked */ -long big_key_read(const struct key *key, char __user *buffer, size_t buflen) +long big_key_read(const struct key *key, char *buffer, size_t buflen) { - size_t datalen = (size_t)key->payload.data[big_key_len]; + struct big_key_payload *payload = to_big_key_payload(key->payload); + size_t datalen = payload->length; long ret; if (!buffer || buflen < datalen) return datalen; if (datalen > BIG_KEY_FILE_THRESHOLD) { - struct big_key_buf *buf; - struct path *path = (struct path *)&key->payload.data[big_key_path]; struct file *file; - u8 *enckey = (u8 *)key->payload.data[big_key_data]; - size_t enclen = datalen + ENC_AUTHTAG_SIZE; + u8 *buf, *enckey = payload->data; + size_t enclen = datalen + CHACHA20POLY1305_AUTHTAG_SIZE; loff_t pos = 0; - buf = big_key_alloc_buffer(enclen); + buf = kvmalloc(enclen, GFP_KERNEL); if (!buf) return -ENOMEM; - file = dentry_open(path, O_RDONLY, current_cred()); + file = dentry_open(&payload->path, O_RDONLY, current_cred()); if (IS_ERR(file)) { ret = PTR_ERR(file); goto error; } /* read file to kernel and decrypt */ - ret = kernel_read(file, buf->virt, enclen, &pos); - if (ret >= 0 && ret != enclen) { - ret = -EIO; + ret = kernel_read(file, buf, enclen, &pos); + if (ret != enclen) { + if (ret >= 0) + ret = -EIO; goto err_fput; } - ret = big_key_crypt(BIG_KEY_DEC, buf, enclen, enckey); - if (ret) + ret = chacha20poly1305_decrypt(buf, buf, enclen, NULL, 0, 0, + enckey) ? 0 : -EBADMSG; + if (unlikely(ret)) goto err_fput; ret = datalen; - /* copy decrypted data to user */ - if (copy_to_user(buffer, buf->virt, datalen) != 0) - ret = -EFAULT; + /* copy out decrypted data */ + memcpy(buffer, buf, datalen); err_fput: fput(file); error: - big_key_free_buffer(buf); + kvfree_sensitive(buf, enclen); } else { ret = datalen; - if (copy_to_user(buffer, key->payload.data[big_key_data], - datalen) != 0) - ret = -EFAULT; + memcpy(buffer, payload->data, datalen); } return ret; @@ -414,39 +284,7 @@ error: */ static int __init big_key_init(void) { - int ret; - - /* init block cipher */ - big_key_aead = crypto_alloc_aead(big_key_alg_name, 0, CRYPTO_ALG_ASYNC); - if (IS_ERR(big_key_aead)) { - ret = PTR_ERR(big_key_aead); - pr_err("Can't alloc crypto: %d\n", ret); - return ret; - } - - if (unlikely(crypto_aead_ivsize(big_key_aead) != BIG_KEY_IV_SIZE)) { - WARN(1, "big key algorithm changed?"); - ret = -EINVAL; - goto free_aead; - } - - ret = crypto_aead_setauthsize(big_key_aead, ENC_AUTHTAG_SIZE); - if (ret < 0) { - pr_err("Can't set crypto auth tag len: %d\n", ret); - goto free_aead; - } - - ret = register_key_type(&key_type_big_key); - if (ret < 0) { - pr_err("Can't register type: %d\n", ret); - goto free_aead; - } - - return 0; - -free_aead: - crypto_free_aead(big_key_aead); - return ret; + return register_key_type(&key_type_big_key); } late_initcall(big_key_init); diff --git a/security/keys/compat.c b/security/keys/compat.c index b975f8f11124..1545efdca562 100644 --- a/security/keys/compat.c +++ b/security/keys/compat.c @@ -12,39 +12,6 @@ #include "internal.h" /* - * Instantiate a key with the specified compatibility multipart payload and - * link the key into the destination keyring if one is given. - * - * The caller must have the appropriate instantiation permit set for this to - * work (see keyctl_assume_authority). No other permissions are required. - * - * If successful, 0 will be returned. - */ -static long compat_keyctl_instantiate_key_iov( - key_serial_t id, - const struct compat_iovec __user *_payload_iov, - unsigned ioc, - key_serial_t ringid) -{ - struct iovec iovstack[UIO_FASTIOV], *iov = iovstack; - struct iov_iter from; - long ret; - - if (!_payload_iov) - ioc = 0; - - ret = compat_import_iovec(WRITE, _payload_iov, ioc, - ARRAY_SIZE(iovstack), &iov, - &from); - if (ret < 0) - return ret; - - ret = keyctl_instantiate_key_common(id, &from, ringid); - kfree(iov); - return ret; -} - -/* * The key control system call, 32-bit compatibility version for 64-bit archs */ COMPAT_SYSCALL_DEFINE5(keyctl, u32, option, @@ -114,8 +81,8 @@ COMPAT_SYSCALL_DEFINE5(keyctl, u32, option, return keyctl_reject_key(arg2, arg3, arg4, arg5); case KEYCTL_INSTANTIATE_IOV: - return compat_keyctl_instantiate_key_iov( - arg2, compat_ptr(arg3), arg4, arg5); + return keyctl_instantiate_key_iov(arg2, compat_ptr(arg3), arg4, + arg5); case KEYCTL_INVALIDATE: return keyctl_invalidate_key(arg2); @@ -156,6 +123,9 @@ COMPAT_SYSCALL_DEFINE5(keyctl, u32, option, case KEYCTL_CAPABILITIES: return keyctl_capabilities(compat_ptr(arg2), arg3); + case KEYCTL_WATCH_KEY: + return keyctl_watch_key(arg2, arg3, arg4); + default: return -EOPNOTSUPP; } diff --git a/security/keys/dh.c b/security/keys/dh.c index c4c629bb1c03..b339760a31dd 100644 --- a/security/keys/dh.c +++ b/security/keys/dh.c @@ -11,10 +11,11 @@ #include <crypto/hash.h> #include <crypto/kpp.h> #include <crypto/dh.h> +#include <crypto/kdf_sp800108.h> #include <keys/user-type.h> #include "internal.h" -static ssize_t dh_data_from_key(key_serial_t keyid, void **data) +static ssize_t dh_data_from_key(key_serial_t keyid, const void **data) { struct key *key; key_ref_t key_ref; @@ -58,9 +59,9 @@ error: static void dh_free_data(struct dh *dh) { - kzfree(dh->key); - kzfree(dh->p); - kzfree(dh->g); + kfree_sensitive(dh->key); + kfree_sensitive(dh->p); + kfree_sensitive(dh->g); } struct dh_completion { @@ -79,17 +80,9 @@ static void dh_crypto_done(struct crypto_async_request *req, int err) complete(&compl->completion); } -struct kdf_sdesc { - struct shash_desc shash; - char ctx[]; -}; - -static int kdf_alloc(struct kdf_sdesc **sdesc_ret, char *hashname) +static int kdf_alloc(struct crypto_shash **hash, char *hashname) { struct crypto_shash *tfm; - struct kdf_sdesc *sdesc; - int size; - int err; /* allocate synchronous hash */ tfm = crypto_alloc_shash(hashname, 0, 0); @@ -98,112 +91,30 @@ static int kdf_alloc(struct kdf_sdesc **sdesc_ret, char *hashname) return PTR_ERR(tfm); } - err = -EINVAL; - if (crypto_shash_digestsize(tfm) == 0) - goto out_free_tfm; - - err = -ENOMEM; - size = sizeof(struct shash_desc) + crypto_shash_descsize(tfm); - sdesc = kmalloc(size, GFP_KERNEL); - if (!sdesc) - goto out_free_tfm; - sdesc->shash.tfm = tfm; + if (crypto_shash_digestsize(tfm) == 0) { + crypto_free_shash(tfm); + return -EINVAL; + } - *sdesc_ret = sdesc; + *hash = tfm; return 0; - -out_free_tfm: - crypto_free_shash(tfm); - return err; } -static void kdf_dealloc(struct kdf_sdesc *sdesc) +static void kdf_dealloc(struct crypto_shash *hash) { - if (!sdesc) - return; - - if (sdesc->shash.tfm) - crypto_free_shash(sdesc->shash.tfm); - - kzfree(sdesc); -} - -/* - * Implementation of the KDF in counter mode according to SP800-108 section 5.1 - * as well as SP800-56A section 5.8.1 (Single-step KDF). - * - * SP800-56A: - * The src pointer is defined as Z || other info where Z is the shared secret - * from DH and other info is an arbitrary string (see SP800-56A section - * 5.8.1.2). - * - * 'dlen' must be a multiple of the digest size. - */ -static int kdf_ctr(struct kdf_sdesc *sdesc, const u8 *src, unsigned int slen, - u8 *dst, unsigned int dlen, unsigned int zlen) -{ - struct shash_desc *desc = &sdesc->shash; - unsigned int h = crypto_shash_digestsize(desc->tfm); - int err = 0; - u8 *dst_orig = dst; - __be32 counter = cpu_to_be32(1); - - while (dlen) { - err = crypto_shash_init(desc); - if (err) - goto err; - - err = crypto_shash_update(desc, (u8 *)&counter, sizeof(__be32)); - if (err) - goto err; - - if (zlen && h) { - u8 tmpbuffer[32]; - size_t chunk = min_t(size_t, zlen, sizeof(tmpbuffer)); - memset(tmpbuffer, 0, chunk); - - do { - err = crypto_shash_update(desc, tmpbuffer, - chunk); - if (err) - goto err; - - zlen -= chunk; - chunk = min_t(size_t, zlen, sizeof(tmpbuffer)); - } while (zlen); - } - - if (src && slen) { - err = crypto_shash_update(desc, src, slen); - if (err) - goto err; - } - - err = crypto_shash_final(desc, dst); - if (err) - goto err; - - dlen -= h; - dst += h; - counter = cpu_to_be32(be32_to_cpu(counter) + 1); - } - - return 0; - -err: - memzero_explicit(dst_orig, dlen); - return err; + if (hash) + crypto_free_shash(hash); } -static int keyctl_dh_compute_kdf(struct kdf_sdesc *sdesc, +static int keyctl_dh_compute_kdf(struct crypto_shash *hash, char __user *buffer, size_t buflen, - uint8_t *kbuf, size_t kbuflen, size_t lzero) + uint8_t *kbuf, size_t kbuflen) { + struct kvec kbuf_iov = { .iov_base = kbuf, .iov_len = kbuflen }; uint8_t *outbuf = NULL; int ret; - size_t outbuf_len = roundup(buflen, - crypto_shash_digestsize(sdesc->shash.tfm)); + size_t outbuf_len = roundup(buflen, crypto_shash_digestsize(hash)); outbuf = kmalloc(outbuf_len, GFP_KERNEL); if (!outbuf) { @@ -211,7 +122,7 @@ static int keyctl_dh_compute_kdf(struct kdf_sdesc *sdesc, goto err; } - ret = kdf_ctr(sdesc, kbuf, kbuflen, outbuf, outbuf_len, lzero); + ret = crypto_kdf108_ctr_generate(hash, &kbuf_iov, 1, outbuf, outbuf_len); if (ret) goto err; @@ -220,7 +131,7 @@ static int keyctl_dh_compute_kdf(struct kdf_sdesc *sdesc, ret = -EFAULT; err: - kzfree(outbuf); + kfree_sensitive(outbuf); return ret; } @@ -240,7 +151,7 @@ long __keyctl_dh_compute(struct keyctl_dh_params __user *params, struct kpp_request *req; uint8_t *secret; uint8_t *outbuf; - struct kdf_sdesc *sdesc = NULL; + struct crypto_shash *hash = NULL; if (!params || (!buffer && buflen)) { ret = -EINVAL; @@ -273,7 +184,7 @@ long __keyctl_dh_compute(struct keyctl_dh_params __user *params, } /* allocate KDF from the kernel crypto API */ - ret = kdf_alloc(&sdesc, hashname); + ret = kdf_alloc(&hash, hashname); kfree(hashname); if (ret) goto out1; @@ -383,9 +294,8 @@ long __keyctl_dh_compute(struct keyctl_dh_params __user *params, goto out6; } - ret = keyctl_dh_compute_kdf(sdesc, buffer, buflen, outbuf, - req->dst_len + kdfcopy->otherinfolen, - outlen - req->dst_len); + ret = keyctl_dh_compute_kdf(hash, buffer, buflen, outbuf, + req->dst_len + kdfcopy->otherinfolen); } else if (copy_to_user(buffer, outbuf, req->dst_len) == 0) { ret = req->dst_len; } else { @@ -395,15 +305,15 @@ long __keyctl_dh_compute(struct keyctl_dh_params __user *params, out6: kpp_request_free(req); out5: - kzfree(outbuf); + kfree_sensitive(outbuf); out4: crypto_free_kpp(tfm); out3: - kzfree(secret); + kfree_sensitive(secret); out2: dh_free_data(&dh_inputs); out1: - kdf_dealloc(sdesc); + kdf_dealloc(hash); return ret; } diff --git a/security/keys/encrypted-keys/ecryptfs_format.c b/security/keys/encrypted-keys/ecryptfs_format.c index a7339d4de811..8fdd76105ce3 100644 --- a/security/keys/encrypted-keys/ecryptfs_format.c +++ b/security/keys/encrypted-keys/ecryptfs_format.c @@ -4,7 +4,7 @@ * * Copyright (C) 2006 International Business Machines Corp. * Copyright (C) 2010 Politecnico di Torino, Italy - * TORSEC group -- http://security.polito.it + * TORSEC group -- https://security.polito.it * * Authors: * Michael A. Halcrow <mahalcro@us.ibm.com> diff --git a/security/keys/encrypted-keys/ecryptfs_format.h b/security/keys/encrypted-keys/ecryptfs_format.h index 939621d870e4..ed8466578616 100644 --- a/security/keys/encrypted-keys/ecryptfs_format.h +++ b/security/keys/encrypted-keys/ecryptfs_format.h @@ -4,7 +4,7 @@ * * Copyright (C) 2006 International Business Machines Corp. * Copyright (C) 2010 Politecnico di Torino, Italy - * TORSEC group -- http://security.polito.it + * TORSEC group -- https://security.polito.it * * Authors: * Michael A. Halcrow <mahalcro@us.ibm.com> diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c index 60720f58cbe0..e05cfc2e49ae 100644 --- a/security/keys/encrypted-keys/encrypted.c +++ b/security/keys/encrypted-keys/encrypted.c @@ -2,7 +2,7 @@ /* * Copyright (C) 2010 IBM Corporation * Copyright (C) 2010 Politecnico di Torino, Italy - * TORSEC group -- http://security.polito.it + * TORSEC group -- https://security.polito.it * * Authors: * Mimi Zohar <zohar@us.ibm.com> @@ -29,7 +29,7 @@ #include <crypto/aes.h> #include <crypto/algapi.h> #include <crypto/hash.h> -#include <crypto/sha.h> +#include <crypto/sha2.h> #include <crypto/skcipher.h> #include "encrypted.h" @@ -78,6 +78,11 @@ static const match_table_t key_tokens = { {Opt_err, NULL} }; +static bool user_decrypted_data = IS_ENABLED(CONFIG_USER_DECRYPTED_DATA); +module_param(user_decrypted_data, bool, 0); +MODULE_PARM_DESC(user_decrypted_data, + "Allow instantiation of encrypted keys using provided decrypted data"); + static int aes_get_sizes(void) { struct crypto_skcipher *tfm; @@ -158,7 +163,7 @@ static int valid_master_desc(const char *new_desc, const char *orig_desc) * datablob_parse - parse the keyctl data * * datablob format: - * new [<format>] <master-key name> <decrypted data length> + * new [<format>] <master-key name> <decrypted data length> [<decrypted data>] * load [<format>] <master-key name> <decrypted data length> * <encrypted iv + data> * update <new-master-key name> @@ -170,7 +175,7 @@ static int valid_master_desc(const char *new_desc, const char *orig_desc) */ static int datablob_parse(char *datablob, const char **format, char **master_desc, char **decrypted_datalen, - char **hex_encoded_iv) + char **hex_encoded_iv, char **decrypted_data) { substring_t args[MAX_OPT_ARGS]; int ret = -EINVAL; @@ -231,6 +236,7 @@ static int datablob_parse(char *datablob, const char **format, "when called from .update method\n", keyword); break; } + *decrypted_data = strsep(&datablob, " \t"); ret = 0; break; case Opt_load: @@ -323,19 +329,6 @@ error: return ukey; } -static int calc_hash(struct crypto_shash *tfm, u8 *digest, - const u8 *buf, unsigned int buflen) -{ - SHASH_DESC_ON_STACK(desc, tfm); - int err; - - desc->tfm = tfm; - - err = crypto_shash_digest(desc, buf, buflen, digest); - shash_desc_zero(desc); - return err; -} - static int calc_hmac(u8 *digest, const u8 *key, unsigned int keylen, const u8 *buf, unsigned int buflen) { @@ -351,7 +344,7 @@ static int calc_hmac(u8 *digest, const u8 *key, unsigned int keylen, err = crypto_shash_setkey(tfm, key, keylen); if (!err) - err = calc_hash(tfm, digest, buf, buflen); + err = crypto_shash_tfm_digest(tfm, buf, buflen, digest); crypto_free_shash(tfm); return err; } @@ -381,8 +374,9 @@ static int get_derived_key(u8 *derived_key, enum derived_key_type key_type, memcpy(derived_buf + strlen(derived_buf) + 1, master_key, master_keylen); - ret = calc_hash(hash_tfm, derived_key, derived_buf, derived_buf_len); - kzfree(derived_buf); + ret = crypto_shash_tfm_digest(hash_tfm, derived_buf, derived_buf_len, + derived_key); + kfree_sensitive(derived_buf); return ret; } @@ -607,7 +601,8 @@ out: static struct encrypted_key_payload *encrypted_key_alloc(struct key *key, const char *format, const char *master_desc, - const char *datalen) + const char *datalen, + const char *decrypted_data) { struct encrypted_key_payload *epayload = NULL; unsigned short datablob_len; @@ -616,6 +611,7 @@ static struct encrypted_key_payload *encrypted_key_alloc(struct key *key, unsigned int encrypted_datalen; unsigned int format_len; long dlen; + int i; int ret; ret = kstrtol(datalen, 10, &dlen); @@ -625,6 +621,24 @@ static struct encrypted_key_payload *encrypted_key_alloc(struct key *key, format_len = (!format) ? strlen(key_format_default) : strlen(format); decrypted_datalen = dlen; payload_datalen = decrypted_datalen; + + if (decrypted_data) { + if (!user_decrypted_data) { + pr_err("encrypted key: instantiation of keys using provided decrypted data is disabled since CONFIG_USER_DECRYPTED_DATA is set to false\n"); + return ERR_PTR(-EINVAL); + } + if (strlen(decrypted_data) != decrypted_datalen) { + pr_err("encrypted key: decrypted data provided does not match decrypted data length provided\n"); + return ERR_PTR(-EINVAL); + } + for (i = 0; i < strlen(decrypted_data); i++) { + if (!isxdigit(decrypted_data[i])) { + pr_err("encrypted key: decrypted data provided must contain only hexadecimal characters\n"); + return ERR_PTR(-EINVAL); + } + } + } + if (format) { if (!strcmp(format, key_format_ecryptfs)) { if (dlen != ECRYPTFS_MAX_KEY_BYTES) { @@ -752,13 +766,14 @@ static void __ekey_init(struct encrypted_key_payload *epayload, /* * encrypted_init - initialize an encrypted key * - * For a new key, use a random number for both the iv and data - * itself. For an old key, decrypt the hex encoded data. + * For a new key, use either a random number or user-provided decrypted data in + * case it is provided. A random number is used for the iv in both cases. For + * an old key, decrypt the hex encoded data. */ static int encrypted_init(struct encrypted_key_payload *epayload, const char *key_desc, const char *format, const char *master_desc, const char *datalen, - const char *hex_encoded_iv) + const char *hex_encoded_iv, const char *decrypted_data) { int ret = 0; @@ -772,21 +787,26 @@ static int encrypted_init(struct encrypted_key_payload *epayload, } __ekey_init(epayload, format, master_desc, datalen); - if (!hex_encoded_iv) { - get_random_bytes(epayload->iv, ivsize); - - get_random_bytes(epayload->decrypted_data, - epayload->decrypted_datalen); - } else + if (hex_encoded_iv) { ret = encrypted_key_decrypt(epayload, format, hex_encoded_iv); + } else if (decrypted_data) { + get_random_bytes(epayload->iv, ivsize); + memcpy(epayload->decrypted_data, decrypted_data, + epayload->decrypted_datalen); + } else { + get_random_bytes(epayload->iv, ivsize); + get_random_bytes(epayload->decrypted_data, epayload->decrypted_datalen); + } return ret; } /* * encrypted_instantiate - instantiate an encrypted key * - * Decrypt an existing encrypted datablob or create a new encrypted key - * based on a kernel random number. + * Instantiates the key: + * - by decrypting an existing encrypted datablob, or + * - by creating a new encrypted key based on a kernel random number, or + * - using provided decrypted data. * * On success, return 0. Otherwise return errno. */ @@ -799,6 +819,7 @@ static int encrypted_instantiate(struct key *key, char *master_desc = NULL; char *decrypted_datalen = NULL; char *hex_encoded_iv = NULL; + char *decrypted_data = NULL; size_t datalen = prep->datalen; int ret; @@ -811,26 +832,26 @@ static int encrypted_instantiate(struct key *key, datablob[datalen] = 0; memcpy(datablob, prep->data, datalen); ret = datablob_parse(datablob, &format, &master_desc, - &decrypted_datalen, &hex_encoded_iv); + &decrypted_datalen, &hex_encoded_iv, &decrypted_data); if (ret < 0) goto out; epayload = encrypted_key_alloc(key, format, master_desc, - decrypted_datalen); + decrypted_datalen, decrypted_data); if (IS_ERR(epayload)) { ret = PTR_ERR(epayload); goto out; } ret = encrypted_init(epayload, key->description, format, master_desc, - decrypted_datalen, hex_encoded_iv); + decrypted_datalen, hex_encoded_iv, decrypted_data); if (ret < 0) { - kzfree(epayload); + kfree_sensitive(epayload); goto out; } rcu_assign_keypointer(key, epayload); out: - kzfree(datablob); + kfree_sensitive(datablob); return ret; } @@ -839,7 +860,7 @@ static void encrypted_rcu_free(struct rcu_head *rcu) struct encrypted_key_payload *epayload; epayload = container_of(rcu, struct encrypted_key_payload, rcu); - kzfree(epayload); + kfree_sensitive(epayload); } /* @@ -872,7 +893,7 @@ static int encrypted_update(struct key *key, struct key_preparsed_payload *prep) buf[datalen] = 0; memcpy(buf, prep->data, datalen); - ret = datablob_parse(buf, &format, &new_master_desc, NULL, NULL); + ret = datablob_parse(buf, &format, &new_master_desc, NULL, NULL, NULL); if (ret < 0) goto out; @@ -881,7 +902,7 @@ static int encrypted_update(struct key *key, struct key_preparsed_payload *prep) goto out; new_epayload = encrypted_key_alloc(key, epayload->format, - new_master_desc, epayload->datalen); + new_master_desc, epayload->datalen, NULL); if (IS_ERR(new_epayload)) { ret = PTR_ERR(new_epayload); goto out; @@ -897,19 +918,19 @@ static int encrypted_update(struct key *key, struct key_preparsed_payload *prep) rcu_assign_keypointer(key, new_epayload); call_rcu(&epayload->rcu, encrypted_rcu_free); out: - kzfree(buf); + kfree_sensitive(buf); return ret; } /* - * encrypted_read - format and copy the encrypted data to userspace + * encrypted_read - format and copy out the encrypted data * * The resulting datablob format is: * <master-key name> <decrypted data length> <encrypted iv> <encrypted data> * * On success, return to userspace the encrypted key datablob size. */ -static long encrypted_read(const struct key *key, char __user *buffer, +static long encrypted_read(const struct key *key, char *buffer, size_t buflen) { struct encrypted_key_payload *epayload; @@ -957,9 +978,8 @@ static long encrypted_read(const struct key *key, char __user *buffer, key_put(mkey); memzero_explicit(derived_key, sizeof(derived_key)); - if (copy_to_user(buffer, ascii_buf, asciiblob_len) != 0) - ret = -EFAULT; - kzfree(ascii_buf); + memcpy(buffer, ascii_buf, asciiblob_len); + kfree_sensitive(ascii_buf); return asciiblob_len; out: @@ -974,7 +994,7 @@ out: */ static void encrypted_destroy(struct key *key) { - kzfree(key->payload.data[0]); + kfree_sensitive(key->payload.data[0]); } struct key_type key_type_encrypted = { diff --git a/security/keys/encrypted-keys/masterkey_trusted.c b/security/keys/encrypted-keys/masterkey_trusted.c index c68528aa49c6..e6d22ce77e98 100644 --- a/security/keys/encrypted-keys/masterkey_trusted.c +++ b/security/keys/encrypted-keys/masterkey_trusted.c @@ -2,7 +2,7 @@ /* * Copyright (C) 2010 IBM Corporation * Copyright (C) 2010 Politecnico di Torino, Italy - * TORSEC group -- http://security.polito.it + * TORSEC group -- https://security.polito.it * * Authors: * Mimi Zohar <zohar@us.ibm.com> diff --git a/security/keys/gc.c b/security/keys/gc.c index 671dd730ecfc..3c90807476eb 100644 --- a/security/keys/gc.c +++ b/security/keys/gc.c @@ -131,6 +131,11 @@ static noinline void key_gc_unused_keys(struct list_head *keys) kdebug("- %u", key->serial); key_check(key); +#ifdef CONFIG_KEY_NOTIFICATIONS + remove_watch_list(key->watchers, key->serial); + key->watchers = NULL; +#endif + /* Throw away the key data if the key is instantiated */ if (state == KEY_IS_POSITIVE && key->type->destroy) key->type->destroy(key); diff --git a/security/keys/internal.h b/security/keys/internal.h index ba3e2da14cef..3c1e7122076b 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -15,7 +15,10 @@ #include <linux/task_work.h> #include <linux/keyctl.h> #include <linux/refcount.h> +#include <linux/watch_queue.h> #include <linux/compat.h> +#include <linux/mm.h> +#include <linux/vmalloc.h> struct iovec; @@ -97,7 +100,8 @@ extern int __key_link_begin(struct key *keyring, const struct keyring_index_key *index_key, struct assoc_array_edit **_edit); extern int __key_link_check_live_key(struct key *keyring, struct key *key); -extern void __key_link(struct key *key, struct assoc_array_edit **_edit); +extern void __key_link(struct key *keyring, struct key *key, + struct assoc_array_edit **_edit); extern void __key_link_end(struct key *keyring, const struct keyring_index_key *index_key, struct assoc_array_edit *edit); @@ -161,9 +165,6 @@ extern struct key *request_key_and_link(struct key_type *type, extern bool lookup_user_key_possessed(const struct key *key, const struct key_match_data *match_data); -#define KEY_LOOKUP_CREATE 0x01 -#define KEY_LOOKUP_PARTIAL 0x02 -#define KEY_LOOKUP_FOR_UNLINK 0x04 extern long join_session_keyring(const char *name); extern void key_change_session_keyring(struct callback_head *twork); @@ -179,14 +180,32 @@ extern void key_gc_keytype(struct key_type *ktype); extern int key_task_permission(const key_ref_t key_ref, const struct cred *cred, - key_perm_t perm); + enum key_need_perm need_perm); + +static inline void notify_key(struct key *key, + enum key_notification_subtype subtype, u32 aux) +{ +#ifdef CONFIG_KEY_NOTIFICATIONS + struct key_notification n = { + .watch.type = WATCH_TYPE_KEY_NOTIFY, + .watch.subtype = subtype, + .watch.info = watch_sizeof(n), + .key_id = key_serial(key), + .aux = aux, + }; + + post_watch_notification(key->watchers, &n.watch, current_cred(), + n.key_id); +#endif +} /* * Check to see whether permission is granted to use a key in the desired way. */ -static inline int key_permission(const key_ref_t key_ref, unsigned perm) +static inline int key_permission(const key_ref_t key_ref, + enum key_need_perm need_perm) { - return key_task_permission(key_ref, current_cred(), perm); + return key_task_permission(key_ref, current_cred(), need_perm); } extern struct key_type key_type_request_key_auth; @@ -241,11 +260,6 @@ extern long keyctl_instantiate_key_iov(key_serial_t, const struct iovec __user *, unsigned, key_serial_t); extern long keyctl_invalidate_key(key_serial_t); - -struct iov_iter; -extern long keyctl_instantiate_key_common(key_serial_t, - struct iov_iter *, - key_serial_t); extern long keyctl_restrict_keyring(key_serial_t id, const char __user *_type, const char __user *_restriction); @@ -331,6 +345,15 @@ static inline long keyctl_pkey_e_d_s(int op, extern long keyctl_capabilities(unsigned char __user *_buffer, size_t buflen); +#ifdef CONFIG_KEY_NOTIFICATIONS +extern long keyctl_watch_key(key_serial_t, int, int); +#else +static inline long keyctl_watch_key(key_serial_t key_id, int watch_fd, int watch_id) +{ + return -EOPNOTSUPP; +} +#endif + /* * Debugging key validation */ @@ -348,5 +371,4 @@ static inline void key_check(const struct key *key) #define key_check(key) do {} while(0) #endif - #endif /* _INTERNAL_H */ diff --git a/security/keys/key.c b/security/keys/key.c index 718bf7217420..c45afdd1dfbb 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -303,6 +303,8 @@ struct key *key_alloc(struct key_type *type, const char *desc, key->flags |= 1 << KEY_FLAG_BUILTIN; if (flags & KEY_ALLOC_UID_KEYRING) key->flags |= 1 << KEY_FLAG_UID_KEYRING; + if (flags & KEY_ALLOC_SET_KEEP) + key->flags |= 1 << KEY_FLAG_KEEP; #ifdef KEY_DEBUGGING key->magic = KEY_DEBUG_MAGIC; @@ -382,7 +384,7 @@ int key_payload_reserve(struct key *key, size_t datalen) spin_lock(&key->user->lock); if (delta > 0 && - (key->user->qnbytes + delta >= maxbytes || + (key->user->qnbytes + delta > maxbytes || key->user->qnbytes + delta < key->user->qnbytes)) { ret = -EDQUOT; } @@ -444,6 +446,7 @@ static int __key_instantiate_and_link(struct key *key, /* mark the key as being instantiated */ atomic_inc(&key->user->nikeys); mark_key_instantiated(key, 0); + notify_key(key, NOTIFY_KEY_INSTANTIATED, 0); if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags)) awaken = 1; @@ -453,7 +456,7 @@ static int __key_instantiate_and_link(struct key *key, if (test_bit(KEY_FLAG_KEEP, &keyring->flags)) set_bit(KEY_FLAG_KEEP, &key->flags); - __key_link(key, _edit); + __key_link(keyring, key, _edit); } /* disable the authorisation key */ @@ -503,6 +506,7 @@ int key_instantiate_and_link(struct key *key, int ret; memset(&prep, 0, sizeof(prep)); + prep.orig_description = key->description; prep.data = data; prep.datalen = datalen; prep.quotalen = key->type->def_datalen; @@ -601,6 +605,7 @@ int key_reject_and_link(struct key *key, /* mark the key as being negatively instantiated */ atomic_inc(&key->user->nikeys); mark_key_instantiated(key, -error); + notify_key(key, NOTIFY_KEY_INSTANTIATED, -error); key->expiry = ktime_get_real_seconds() + timeout; key_schedule_gc(key->expiry + key_gc_delay); @@ -611,7 +616,7 @@ int key_reject_and_link(struct key *key, /* and link it into the destination keyring */ if (keyring && link_ret == 0) - __key_link(key, &edit); + __key_link(keyring, key, &edit); /* disable the authorisation key */ if (authkey) @@ -764,9 +769,11 @@ static inline key_ref_t __key_update(key_ref_t key_ref, down_write(&key->sem); ret = key->type->update(key, prep); - if (ret == 0) + if (ret == 0) { /* Updating a negative key positively instantiates it */ mark_key_instantiated(key, 0); + notify_key(key, NOTIFY_KEY_UPDATED, 0); + } up_write(&key->sem); @@ -850,6 +857,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, goto error_put_type; memset(&prep, 0, sizeof(prep)); + prep.orig_description = description; prep.data = payload; prep.datalen = plen; prep.quotalen = index_key.type->def_datalen; @@ -1023,9 +1031,11 @@ int key_update(key_ref_t key_ref, const void *payload, size_t plen) down_write(&key->sem); ret = key->type->update(key, &prep); - if (ret == 0) + if (ret == 0) { /* Updating a negative key positively instantiates it */ mark_key_instantiated(key, 0); + notify_key(key, NOTIFY_KEY_UPDATED, 0); + } up_write(&key->sem); @@ -1057,15 +1067,17 @@ void key_revoke(struct key *key) * instantiated */ down_write_nested(&key->sem, 1); - if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags) && - key->type->revoke) - key->type->revoke(key); - - /* set the death time to no more than the expiry time */ - time = ktime_get_real_seconds(); - if (key->revoked_at == 0 || key->revoked_at > time) { - key->revoked_at = time; - key_schedule_gc(key->revoked_at + key_gc_delay); + if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags)) { + notify_key(key, NOTIFY_KEY_REVOKED, 0); + if (key->type->revoke) + key->type->revoke(key); + + /* set the death time to no more than the expiry time */ + time = ktime_get_real_seconds(); + if (key->revoked_at == 0 || key->revoked_at > time) { + key->revoked_at = time; + key_schedule_gc(key->revoked_at + key_gc_delay); + } } up_write(&key->sem); @@ -1087,8 +1099,10 @@ void key_invalidate(struct key *key) if (!test_bit(KEY_FLAG_INVALIDATED, &key->flags)) { down_write_nested(&key->sem, 1); - if (!test_and_set_bit(KEY_FLAG_INVALIDATED, &key->flags)) + if (!test_and_set_bit(KEY_FLAG_INVALIDATED, &key->flags)) { + notify_key(key, NOTIFY_KEY_INVALIDATED, 0); key_schedule_gc_links(); + } up_write(&key->sem); } } diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 9b898c969558..96a92a645216 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -37,7 +37,9 @@ static const unsigned char keyrings_capabilities[2] = { KEYCTL_CAPS0_MOVE ), [1] = (KEYCTL_CAPS1_NS_KEYRING_NAME | - KEYCTL_CAPS1_NS_KEY_TAG), + KEYCTL_CAPS1_NS_KEY_TAG | + (IS_ENABLED(CONFIG_KEY_NOTIFICATIONS) ? KEYCTL_CAPS1_NOTIFICATIONS : 0) + ), }; static int key_get_type_from_user(char *type, @@ -142,10 +144,7 @@ SYSCALL_DEFINE5(add_key, const char __user *, _type, key_ref_put(keyring_ref); error3: - if (payload) { - memzero_explicit(payload, plen); - kvfree(payload); - } + kvfree_sensitive(payload, plen); error2: kfree(description); error: @@ -339,7 +338,7 @@ long keyctl_update_key(key_serial_t id, payload = NULL; if (plen) { ret = -ENOMEM; - payload = kmalloc(plen, GFP_KERNEL); + payload = kvmalloc(plen, GFP_KERNEL); if (!payload) goto error; @@ -360,7 +359,7 @@ long keyctl_update_key(key_serial_t id, key_ref_put(key_ref); error2: - kzfree(payload); + kvfree_sensitive(payload, plen); error: return ret; } @@ -432,7 +431,7 @@ long keyctl_invalidate_key(key_serial_t id) /* Root is permitted to invalidate certain special keys */ if (capable(CAP_SYS_ADMIN)) { - key_ref = lookup_user_key(id, 0, 0); + key_ref = lookup_user_key(id, 0, KEY_SYSADMIN_OVERRIDE); if (IS_ERR(key_ref)) goto error; if (test_bit(KEY_FLAG_ROOT_CAN_INVAL, @@ -477,7 +476,8 @@ long keyctl_keyring_clear(key_serial_t ringid) /* Root is permitted to invalidate certain special keyrings */ if (capable(CAP_SYS_ADMIN)) { - keyring_ref = lookup_user_key(ringid, 0, 0); + keyring_ref = lookup_user_key(ringid, 0, + KEY_SYSADMIN_OVERRIDE); if (IS_ERR(keyring_ref)) goto error; if (test_bit(KEY_FLAG_ROOT_CAN_CLEAR, @@ -506,7 +506,7 @@ error: * keyring, otherwise replace the link to the matching key with a link to the * new key. * - * The key must grant the caller Link permission and the the keyring must grant + * The key must grant the caller Link permission and the keyring must grant * the caller Write permission. Furthermore, if an additional link is created, * the keyring's quota will be extended. * @@ -561,7 +561,7 @@ long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid) goto error; } - key_ref = lookup_user_key(id, KEY_LOOKUP_FOR_UNLINK, 0); + key_ref = lookup_user_key(id, KEY_LOOKUP_PARTIAL, KEY_NEED_UNLINK); if (IS_ERR(key_ref)) { ret = PTR_ERR(key_ref); goto error2; @@ -661,7 +661,7 @@ long keyctl_describe_key(key_serial_t keyid, key_put(instkey); key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, - 0); + KEY_AUTHTOKEN_OVERRIDE); if (!IS_ERR(key_ref)) goto okay; } @@ -798,6 +798,21 @@ error: } /* + * Call the read method + */ +static long __keyctl_read_key(struct key *key, char *buffer, size_t buflen) +{ + long ret; + + down_read(&key->sem); + ret = key_validate(key); + if (ret == 0) + ret = key->type->read(key, buffer, buflen); + up_read(&key->sem); + return ret; +} + +/* * Read a key's payload. * * The key must either grant the caller Read permission, or it must grant the @@ -812,26 +827,28 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) struct key *key; key_ref_t key_ref; long ret; + char *key_data = NULL; + size_t key_data_len; /* find the key first */ - key_ref = lookup_user_key(keyid, 0, 0); + key_ref = lookup_user_key(keyid, 0, KEY_DEFER_PERM_CHECK); if (IS_ERR(key_ref)) { ret = -ENOKEY; - goto error; + goto out; } key = key_ref_to_ptr(key_ref); ret = key_read_state(key); if (ret < 0) - goto error2; /* Negatively instantiated */ + goto key_put_out; /* Negatively instantiated */ /* see if we can read it directly */ ret = key_permission(key_ref, KEY_NEED_READ); if (ret == 0) goto can_read_key; if (ret != -EACCES) - goto error2; + goto key_put_out; /* we can't; see if it's searchable from this process's keyrings * - we automatically take account of the fact that it may be @@ -839,26 +856,78 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) */ if (!is_key_possessed(key_ref)) { ret = -EACCES; - goto error2; + goto key_put_out; } /* the key is probably readable - now try to read it */ can_read_key: - ret = -EOPNOTSUPP; - if (key->type->read) { - /* Read the data with the semaphore held (since we might sleep) - * to protect against the key being updated or revoked. + if (!key->type->read) { + ret = -EOPNOTSUPP; + goto key_put_out; + } + + if (!buffer || !buflen) { + /* Get the key length from the read method */ + ret = __keyctl_read_key(key, NULL, 0); + goto key_put_out; + } + + /* + * Read the data with the semaphore held (since we might sleep) + * to protect against the key being updated or revoked. + * + * Allocating a temporary buffer to hold the keys before + * transferring them to user buffer to avoid potential + * deadlock involving page fault and mmap_lock. + * + * key_data_len = (buflen <= PAGE_SIZE) + * ? buflen : actual length of key data + * + * This prevents allocating arbitrary large buffer which can + * be much larger than the actual key length. In the latter case, + * at least 2 passes of this loop is required. + */ + key_data_len = (buflen <= PAGE_SIZE) ? buflen : 0; + for (;;) { + if (key_data_len) { + key_data = kvmalloc(key_data_len, GFP_KERNEL); + if (!key_data) { + ret = -ENOMEM; + goto key_put_out; + } + } + + ret = __keyctl_read_key(key, key_data, key_data_len); + + /* + * Read methods will just return the required length without + * any copying if the provided length isn't large enough. */ - down_read(&key->sem); - ret = key_validate(key); - if (ret == 0) - ret = key->type->read(key, buffer, buflen); - up_read(&key->sem); + if (ret <= 0 || ret > buflen) + break; + + /* + * The key may change (unlikely) in between 2 consecutive + * __keyctl_read_key() calls. In this case, we reallocate + * a larger buffer and redo the key read when + * key_data_len < ret <= buflen. + */ + if (ret > key_data_len) { + if (unlikely(key_data)) + kvfree_sensitive(key_data, key_data_len); + key_data_len = ret; + continue; /* Allocate buffer */ + } + + if (copy_to_user(buffer, key_data, ret)) + ret = -EFAULT; + break; } + kvfree_sensitive(key_data, key_data_len); -error2: +key_put_out: key_put(key); -error: +out: return ret; } @@ -937,8 +1006,8 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group) key_quota_root_maxbytes : key_quota_maxbytes; spin_lock(&newowner->lock); - if (newowner->qnkeys + 1 >= maxkeys || - newowner->qnbytes + key->quotalen >= maxbytes || + if (newowner->qnkeys + 1 > maxkeys || + newowner->qnbytes + key->quotalen > maxbytes || newowner->qnbytes + key->quotalen < newowner->qnbytes) goto quota_overrun; @@ -970,6 +1039,7 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group) if (group != (gid_t) -1) key->gid = gid; + notify_key(key, NOTIFY_KEY_SETATTR, 0); ret = 0; error_put: @@ -1020,6 +1090,7 @@ long keyctl_setperm_key(key_serial_t id, key_perm_t perm) /* if we're not the sysadmin, we can only change a key that we own */ if (capable(CAP_SYS_ADMIN) || uid_eq(key->uid, current_fsuid())) { key->perm = perm; + notify_key(key, NOTIFY_KEY_SETATTR, 0); ret = 0; } @@ -1093,7 +1164,7 @@ static int keyctl_change_reqkey_auth(struct key *key) * * If successful, 0 will be returned. */ -long keyctl_instantiate_key_common(key_serial_t id, +static long keyctl_instantiate_key_common(key_serial_t id, struct iov_iter *from, key_serial_t ringid) { @@ -1156,10 +1227,7 @@ long keyctl_instantiate_key_common(key_serial_t id, keyctl_change_reqkey_auth(NULL); error2: - if (payload) { - memzero_explicit(payload, plen); - kvfree(payload); - } + kvfree_sensitive(payload, plen); error: return ret; } @@ -1398,7 +1466,7 @@ long keyctl_set_timeout(key_serial_t id, unsigned timeout) key_put(instkey); key_ref = lookup_user_key(id, KEY_LOOKUP_PARTIAL, - 0); + KEY_AUTHTOKEN_OVERRIDE); if (!IS_ERR(key_ref)) goto okay; } @@ -1411,10 +1479,12 @@ long keyctl_set_timeout(key_serial_t id, unsigned timeout) okay: key = key_ref_to_ptr(key_ref); ret = 0; - if (test_bit(KEY_FLAG_KEEP, &key->flags)) + if (test_bit(KEY_FLAG_KEEP, &key->flags)) { ret = -EPERM; - else + } else { key_set_timeout(key, timeout); + notify_key(key, NOTIFY_KEY_SETATTR, 0); + } key_put(key); error: @@ -1504,7 +1574,8 @@ long keyctl_get_security(key_serial_t keyid, return PTR_ERR(instkey); key_put(instkey); - key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, 0); + key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, + KEY_AUTHTOKEN_OVERRIDE); if (IS_ERR(key_ref)) return PTR_ERR(key_ref); } @@ -1622,7 +1693,7 @@ long keyctl_session_to_parent(void) /* the replacement session keyring is applied just prior to userspace * restarting */ - ret = task_work_add(parent, newwork, true); + ret = task_work_add(parent, newwork, TWA_RESUME); if (!ret) newwork = NULL; unlock: @@ -1688,6 +1759,90 @@ error: return ret; } +#ifdef CONFIG_KEY_NOTIFICATIONS +/* + * Watch for changes to a key. + * + * The caller must have View permission to watch a key or keyring. + */ +long keyctl_watch_key(key_serial_t id, int watch_queue_fd, int watch_id) +{ + struct watch_queue *wqueue; + struct watch_list *wlist = NULL; + struct watch *watch = NULL; + struct key *key; + key_ref_t key_ref; + long ret; + + if (watch_id < -1 || watch_id > 0xff) + return -EINVAL; + + key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE, KEY_NEED_VIEW); + if (IS_ERR(key_ref)) + return PTR_ERR(key_ref); + key = key_ref_to_ptr(key_ref); + + wqueue = get_watch_queue(watch_queue_fd); + if (IS_ERR(wqueue)) { + ret = PTR_ERR(wqueue); + goto err_key; + } + + if (watch_id >= 0) { + ret = -ENOMEM; + if (!key->watchers) { + wlist = kzalloc(sizeof(*wlist), GFP_KERNEL); + if (!wlist) + goto err_wqueue; + init_watch_list(wlist, NULL); + } + + watch = kzalloc(sizeof(*watch), GFP_KERNEL); + if (!watch) + goto err_wlist; + + init_watch(watch, wqueue); + watch->id = key->serial; + watch->info_id = (u32)watch_id << WATCH_INFO_ID__SHIFT; + + ret = security_watch_key(key); + if (ret < 0) + goto err_watch; + + down_write(&key->sem); + if (!key->watchers) { + key->watchers = wlist; + wlist = NULL; + } + + ret = add_watch_to_object(watch, key->watchers); + up_write(&key->sem); + + if (ret == 0) + watch = NULL; + } else { + ret = -EBADSLT; + if (key->watchers) { + down_write(&key->sem); + ret = remove_watch_from_object(key->watchers, + wqueue, key_serial(key), + false); + up_write(&key->sem); + } + } + +err_watch: + kfree(watch); +err_wlist: + kfree(wlist); +err_wqueue: + put_watch_queue(wqueue); +err_key: + key_put(key); + return ret; +} +#endif /* CONFIG_KEY_NOTIFICATIONS */ + /* * Get keyrings subsystem capabilities. */ @@ -1857,6 +2012,9 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, case KEYCTL_CAPABILITIES: return keyctl_capabilities((unsigned char __user *)arg2, (size_t)arg3); + case KEYCTL_WATCH_KEY: + return keyctl_watch_key((key_serial_t)arg2, (int)arg3, (int)arg4); + default: return -EOPNOTSUPP; } diff --git a/security/keys/keyctl_pkey.c b/security/keys/keyctl_pkey.c index 931d8dfb4a7f..97bc27bbf079 100644 --- a/security/keys/keyctl_pkey.c +++ b/security/keys/keyctl_pkey.c @@ -135,15 +135,23 @@ static int keyctl_pkey_params_get_2(const struct keyctl_pkey_params __user *_par switch (op) { case KEYCTL_PKEY_ENCRYPT: + if (uparams.in_len > info.max_dec_size || + uparams.out_len > info.max_enc_size) + return -EINVAL; + break; case KEYCTL_PKEY_DECRYPT: if (uparams.in_len > info.max_enc_size || uparams.out_len > info.max_dec_size) return -EINVAL; break; case KEYCTL_PKEY_SIGN: + if (uparams.in_len > info.max_data_size || + uparams.out_len > info.max_sig_size) + return -EINVAL; + break; case KEYCTL_PKEY_VERIFY: - if (uparams.in_len > info.max_sig_size || - uparams.out_len > info.max_data_size) + if (uparams.in_len > info.max_data_size || + uparams.in2_len > info.max_sig_size) return -EINVAL; break; default: @@ -151,7 +159,7 @@ static int keyctl_pkey_params_get_2(const struct keyctl_pkey_params __user *_par } params->in_len = uparams.in_len; - params->out_len = uparams.out_len; + params->out_len = uparams.out_len; /* Note: same as in2_len */ return 0; } @@ -166,8 +174,6 @@ long keyctl_pkey_query(key_serial_t id, struct kernel_pkey_query res; long ret; - memset(¶ms, 0, sizeof(params)); - ret = keyctl_pkey_params_get(id, _info, ¶ms); if (ret < 0) goto error; diff --git a/security/keys/keyring.c b/security/keys/keyring.c index febf36c6ddc5..4448758f643a 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -79,7 +79,7 @@ static void keyring_revoke(struct key *keyring); static void keyring_destroy(struct key *keyring); static void keyring_describe(const struct key *keyring, struct seq_file *m); static long keyring_read(const struct key *keyring, - char __user *buffer, size_t buflen); + char *buffer, size_t buflen); struct key_type key_type_keyring = { .name = "keyring", @@ -452,14 +452,13 @@ static void keyring_describe(const struct key *keyring, struct seq_file *m) struct keyring_read_iterator_context { size_t buflen; size_t count; - key_serial_t __user *buffer; + key_serial_t *buffer; }; static int keyring_read_iterator(const void *object, void *data) { struct keyring_read_iterator_context *ctx = data; const struct key *key = keyring_ptr_to_key(object); - int ret; kenter("{%s,%d},,{%zu/%zu}", key->type->name, key->serial, ctx->count, ctx->buflen); @@ -467,10 +466,7 @@ static int keyring_read_iterator(const void *object, void *data) if (ctx->count >= ctx->buflen) return 1; - ret = put_user(key->serial, ctx->buffer); - if (ret < 0) - return ret; - ctx->buffer++; + *ctx->buffer++ = key->serial; ctx->count += sizeof(key->serial); return 0; } @@ -483,7 +479,7 @@ static int keyring_read_iterator(const void *object, void *data) * times. */ static long keyring_read(const struct key *keyring, - char __user *buffer, size_t buflen) + char *buffer, size_t buflen) { struct keyring_read_iterator_context ctx; long ret; @@ -495,7 +491,7 @@ static long keyring_read(const struct key *keyring, /* Copy as many key IDs as fit into the buffer */ if (buffer && buflen) { - ctx.buffer = (key_serial_t __user *)buffer; + ctx.buffer = (key_serial_t *)buffer; ctx.buflen = buflen; ctx.count = 0; ret = assoc_array_iterate(&keyring->keys, @@ -885,7 +881,7 @@ found: * * Keys are matched to the type provided and are then filtered by the match * function, which is given the description to use in any way it sees fit. The - * match function may use any attributes of a key that it wishes to to + * match function may use any attributes of a key that it wishes to * determine the match. Normally the match function from the key type would be * used. * @@ -1060,12 +1056,14 @@ int keyring_restrict(key_ref_t keyring_ref, const char *type, down_write(&keyring->sem); down_write(&keyring_serialise_restrict_sem); - if (keyring->restrict_link) + if (keyring->restrict_link) { ret = -EEXIST; - else if (keyring_detect_restriction_cycle(keyring, restrict_link)) + } else if (keyring_detect_restriction_cycle(keyring, restrict_link)) { ret = -EDEADLK; - else + } else { keyring->restrict_link = restrict_link; + notify_key(keyring, NOTIFY_KEY_SETATTR, 0); + } up_write(&keyring_serialise_restrict_sem); up_write(&keyring->sem); @@ -1206,7 +1204,7 @@ static int keyring_detect_cycle_iterator(const void *object, } /* - * See if a cycle will will be created by inserting acyclic tree B in acyclic + * See if a cycle will be created by inserting acyclic tree B in acyclic * tree A at the topmost level (ie: as a direct child of A). * * Since we are adding B to A at the top level, checking for cycles should just @@ -1366,12 +1364,14 @@ int __key_link_check_live_key(struct key *keyring, struct key *key) * holds at most one link to any given key of a particular type+description * combination. */ -void __key_link(struct key *key, struct assoc_array_edit **_edit) +void __key_link(struct key *keyring, struct key *key, + struct assoc_array_edit **_edit) { __key_get(key); assoc_array_insert_set_object(*_edit, keyring_key_to_ptr(key)); assoc_array_apply_edit(*_edit); *_edit = NULL; + notify_key(keyring, NOTIFY_KEY_LINKED, key_serial(key)); } /* @@ -1455,7 +1455,7 @@ int key_link(struct key *keyring, struct key *key) if (ret == 0) ret = __key_link_check_live_key(keyring, key); if (ret == 0) - __key_link(key, &edit); + __key_link(keyring, key, &edit); error_end: __key_link_end(keyring, &key->index_key, edit); @@ -1487,7 +1487,7 @@ static int __key_unlink_begin(struct key *keyring, struct key *key, struct assoc_array_edit *edit; BUG_ON(*_edit != NULL); - + edit = assoc_array_delete(&keyring->keys, &keyring_assoc_array_ops, &key->index_key); if (IS_ERR(edit)) @@ -1507,6 +1507,7 @@ static void __key_unlink(struct key *keyring, struct key *key, struct assoc_array_edit **_edit) { assoc_array_apply_edit(*_edit); + notify_key(keyring, NOTIFY_KEY_UNLINKED, key_serial(key)); *_edit = NULL; key_payload_reserve(keyring, keyring->datalen - KEYQUOTA_LINK_BYTES); } @@ -1625,7 +1626,7 @@ int key_move(struct key *key, goto error; __key_unlink(from_keyring, key, &from_edit); - __key_link(key, &to_edit); + __key_link(to_keyring, key, &to_edit); error: __key_link_end(to_keyring, &key->index_key, to_edit); __key_unlink_end(from_keyring, key, from_edit); @@ -1659,6 +1660,7 @@ int keyring_clear(struct key *keyring) } else { if (edit) assoc_array_apply_edit(edit); + notify_key(keyring, NOTIFY_KEY_CLEARED, 0); key_payload_reserve(keyring, 0); ret = 0; } diff --git a/security/keys/permission.c b/security/keys/permission.c index 085f907b64ac..4a61f804e80f 100644 --- a/security/keys/permission.c +++ b/security/keys/permission.c @@ -13,7 +13,7 @@ * key_task_permission - Check a key can be used * @key_ref: The key to check. * @cred: The credentials to use. - * @perm: The permissions to check for. + * @need_perm: The permission required. * * Check to see whether permission is granted to use a key in the desired way, * but permit the security modules to override. @@ -24,12 +24,30 @@ * permissions bits or the LSM check. */ int key_task_permission(const key_ref_t key_ref, const struct cred *cred, - unsigned perm) + enum key_need_perm need_perm) { struct key *key; - key_perm_t kperm; + key_perm_t kperm, mask; int ret; + switch (need_perm) { + default: + WARN_ON(1); + return -EACCES; + case KEY_NEED_UNLINK: + case KEY_SYSADMIN_OVERRIDE: + case KEY_AUTHTOKEN_OVERRIDE: + case KEY_DEFER_PERM_CHECK: + goto lsm; + + case KEY_NEED_VIEW: mask = KEY_OTH_VIEW; break; + case KEY_NEED_READ: mask = KEY_OTH_READ; break; + case KEY_NEED_WRITE: mask = KEY_OTH_WRITE; break; + case KEY_NEED_SEARCH: mask = KEY_OTH_SEARCH; break; + case KEY_NEED_LINK: mask = KEY_OTH_LINK; break; + case KEY_NEED_SETATTR: mask = KEY_OTH_SETATTR; break; + } + key = key_ref_to_ptr(key_ref); /* use the second 8-bits of permissions for keys the caller owns */ @@ -64,13 +82,12 @@ use_these_perms: if (is_key_possessed(key_ref)) kperm |= key->perm >> 24; - kperm = kperm & perm & KEY_NEED_ALL; - - if (kperm != perm) + if ((kperm & mask) != mask) return -EACCES; /* let LSM be the final arbiter */ - return security_key_permission(key_ref, cred, perm); +lsm: + return security_key_permission(key_ref, cred, need_perm); } EXPORT_SYMBOL(key_task_permission); diff --git a/security/keys/proc.c b/security/keys/proc.c index 415f3f1c2da0..d0cde6685627 100644 --- a/security/keys/proc.c +++ b/security/keys/proc.c @@ -139,6 +139,8 @@ static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos) n = key_serial_next(p, v); if (n) *_pos = key_node_serial(n); + else + (*_pos)++; return n; } diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index 09541de31f2f..b5d5333ab330 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -465,7 +465,7 @@ key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx) case -EAGAIN: /* no key */ if (ret) break; - /* fall through */ + fallthrough; case -ENOKEY: /* negative key */ ret = key_ref; break; @@ -487,7 +487,7 @@ key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx) case -EAGAIN: /* no key */ if (ret) break; - /* fall through */ + fallthrough; case -ENOKEY: /* negative key */ ret = key_ref; break; @@ -509,7 +509,7 @@ key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx) case -EAGAIN: /* no key */ if (ret) break; - /* fall through */ + fallthrough; case -ENOKEY: /* negative key */ ret = key_ref; break; @@ -609,7 +609,7 @@ bool lookup_user_key_possessed(const struct key *key, * returned key reference. */ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags, - key_perm_t perm) + enum key_need_perm need_perm) { struct keyring_search_context ctx = { .match_data.cmp = lookup_user_key_possessed, @@ -773,35 +773,34 @@ try_again: /* unlink does not use the nominated key in any way, so can skip all * the permission checks as it is only concerned with the keyring */ - if (lflags & KEY_LOOKUP_FOR_UNLINK) { - ret = 0; - goto error; - } - - if (!(lflags & KEY_LOOKUP_PARTIAL)) { - ret = wait_for_key_construction(key, true); - switch (ret) { - case -ERESTARTSYS: - goto invalid_key; - default: - if (perm) + if (need_perm != KEY_NEED_UNLINK) { + if (!(lflags & KEY_LOOKUP_PARTIAL)) { + ret = wait_for_key_construction(key, true); + switch (ret) { + case -ERESTARTSYS: + goto invalid_key; + default: + if (need_perm != KEY_AUTHTOKEN_OVERRIDE && + need_perm != KEY_DEFER_PERM_CHECK) + goto invalid_key; + break; + case 0: + break; + } + } else if (need_perm != KEY_DEFER_PERM_CHECK) { + ret = key_validate(key); + if (ret < 0) goto invalid_key; - case 0: - break; } - } else if (perm) { - ret = key_validate(key); - if (ret < 0) + + ret = -EIO; + if (!(lflags & KEY_LOOKUP_PARTIAL) && + key_read_state(key) == KEY_IS_UNINSTANTIATED) goto invalid_key; } - ret = -EIO; - if (!(lflags & KEY_LOOKUP_PARTIAL) && - key_read_state(key) == KEY_IS_UNINSTANTIATED) - goto invalid_key; - /* check the permissions */ - ret = key_task_permission(key_ref, ctx.cred, perm); + ret = key_task_permission(key_ref, ctx.cred, need_perm); if (ret < 0) goto invalid_key; @@ -919,6 +918,13 @@ void key_change_session_keyring(struct callback_head *twork) return; } + /* If get_ucounts fails more bits are needed in the refcount */ + if (unlikely(!get_ucounts(old->ucounts))) { + WARN_ONCE(1, "In %s get_ucounts failed\n", __func__); + put_cred(new); + return; + } + new-> uid = old-> uid; new-> euid = old-> euid; new-> suid = old-> suid; @@ -928,6 +934,7 @@ void key_change_session_keyring(struct callback_head *twork) new-> sgid = old-> sgid; new->fsgid = old->fsgid; new->user = get_uid(old->user); + new->ucounts = old->ucounts; new->user_ns = get_user_ns(old->user_ns); new->group_info = get_group_info(old->group_info); diff --git a/security/keys/request_key.c b/security/keys/request_key.c index 957b9e3e1492..2da4404276f0 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -295,26 +295,26 @@ static int construct_get_dest_keyring(struct key **_dest_keyring) } } - /* fall through */ + fallthrough; case KEY_REQKEY_DEFL_THREAD_KEYRING: dest_keyring = key_get(cred->thread_keyring); if (dest_keyring) break; - /* fall through */ + fallthrough; case KEY_REQKEY_DEFL_PROCESS_KEYRING: dest_keyring = key_get(cred->process_keyring); if (dest_keyring) break; - /* fall through */ + fallthrough; case KEY_REQKEY_DEFL_SESSION_KEYRING: dest_keyring = key_get(cred->session_keyring); if (dest_keyring) break; - /* fall through */ + fallthrough; case KEY_REQKEY_DEFL_USER_SESSION_KEYRING: ret = look_up_user_keyrings(NULL, &dest_keyring); if (ret < 0) @@ -418,7 +418,7 @@ static int construct_alloc_key(struct keyring_search_context *ctx, goto key_already_present; if (dest_keyring) - __key_link(key, &edit); + __key_link(dest_keyring, key, &edit); mutex_unlock(&key_construction_mutex); if (dest_keyring) @@ -437,7 +437,7 @@ key_already_present: if (dest_keyring) { ret = __key_link_check_live_key(dest_keyring, key); if (ret == 0) - __key_link(key, &edit); + __key_link(dest_keyring, key, &edit); __key_link_end(dest_keyring, &ctx->index_key, edit); if (ret < 0) goto link_check_failed; diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index ecba39c93fd9..41e9735006d0 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -22,7 +22,7 @@ static int request_key_auth_instantiate(struct key *, static void request_key_auth_describe(const struct key *, struct seq_file *); static void request_key_auth_revoke(struct key *); static void request_key_auth_destroy(struct key *); -static long request_key_auth_read(const struct key *, char __user *, size_t); +static long request_key_auth_read(const struct key *, char *, size_t); /* * The request-key authorisation key type definition. @@ -80,7 +80,7 @@ static void request_key_auth_describe(const struct key *key, * - the key's semaphore is read-locked */ static long request_key_auth_read(const struct key *key, - char __user *buffer, size_t buflen) + char *buffer, size_t buflen) { struct request_key_auth *rka = dereference_key_locked(key); size_t datalen; @@ -97,8 +97,7 @@ static long request_key_auth_read(const struct key *key, if (buflen > datalen) buflen = datalen; - if (copy_to_user(buffer, rka->callout_info, buflen) != 0) - ret = -EFAULT; + memcpy(buffer, rka->callout_info, buflen); } return ret; diff --git a/security/keys/trusted-keys/Kconfig b/security/keys/trusted-keys/Kconfig new file mode 100644 index 000000000000..dbfdd8536468 --- /dev/null +++ b/security/keys/trusted-keys/Kconfig @@ -0,0 +1,38 @@ +config TRUSTED_KEYS_TPM + bool "TPM-based trusted keys" + depends on TCG_TPM >= TRUSTED_KEYS + default y + select CRYPTO + select CRYPTO_HMAC + select CRYPTO_SHA1 + select CRYPTO_HASH_INFO + select ASN1_ENCODER + select OID_REGISTRY + select ASN1 + help + Enable use of the Trusted Platform Module (TPM) as trusted key + backend. Trusted keys are random number symmetric keys, + which will be generated and RSA-sealed by the TPM. + The TPM only unseals the keys, if the boot PCRs and other + criteria match. + +config TRUSTED_KEYS_TEE + bool "TEE-based trusted keys" + depends on TEE >= TRUSTED_KEYS + default y + help + Enable use of the Trusted Execution Environment (TEE) as trusted + key backend. + +config TRUSTED_KEYS_CAAM + bool "CAAM-based trusted keys" + depends on CRYPTO_DEV_FSL_CAAM_JR >= TRUSTED_KEYS + select CRYPTO_DEV_FSL_CAAM_BLOB_GEN + default y + help + Enable use of NXP's Cryptographic Accelerator and Assurance Module + (CAAM) as trusted key backend. + +if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE && !TRUSTED_KEYS_CAAM +comment "No trust source selected!" +endif diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile index 7b73cebbb378..735aa0bc08ef 100644 --- a/security/keys/trusted-keys/Makefile +++ b/security/keys/trusted-keys/Makefile @@ -4,5 +4,13 @@ # obj-$(CONFIG_TRUSTED_KEYS) += trusted.o -trusted-y += trusted_tpm1.o -trusted-y += trusted_tpm2.o +trusted-y += trusted_core.o +trusted-$(CONFIG_TRUSTED_KEYS_TPM) += trusted_tpm1.o + +$(obj)/trusted_tpm2.o: $(obj)/tpm2key.asn1.h +trusted-$(CONFIG_TRUSTED_KEYS_TPM) += trusted_tpm2.o +trusted-$(CONFIG_TRUSTED_KEYS_TPM) += tpm2key.asn1.o + +trusted-$(CONFIG_TRUSTED_KEYS_TEE) += trusted_tee.o + +trusted-$(CONFIG_TRUSTED_KEYS_CAAM) += trusted_caam.o diff --git a/security/keys/trusted-keys/tpm2key.asn1 b/security/keys/trusted-keys/tpm2key.asn1 new file mode 100644 index 000000000000..f57f869ad600 --- /dev/null +++ b/security/keys/trusted-keys/tpm2key.asn1 @@ -0,0 +1,11 @@ +--- +--- ASN.1 for TPM 2.0 keys +--- + +TPMKey ::= SEQUENCE { + type OBJECT IDENTIFIER ({tpm2_key_type}), + emptyAuth [0] EXPLICIT BOOLEAN OPTIONAL, + parent INTEGER ({tpm2_key_parent}), + pubkey OCTET STRING ({tpm2_key_pub}), + privkey OCTET STRING ({tpm2_key_priv}) + } diff --git a/security/keys/trusted-keys/trusted_caam.c b/security/keys/trusted-keys/trusted_caam.c new file mode 100644 index 000000000000..e3415c520c0a --- /dev/null +++ b/security/keys/trusted-keys/trusted_caam.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> + */ + +#include <keys/trusted_caam.h> +#include <keys/trusted-type.h> +#include <linux/build_bug.h> +#include <linux/key-type.h> +#include <soc/fsl/caam-blob.h> + +static struct caam_blob_priv *blobifier; + +#define KEYMOD "SECURE_KEY" + +static_assert(MAX_KEY_SIZE + CAAM_BLOB_OVERHEAD <= CAAM_BLOB_MAX_LEN); +static_assert(MAX_BLOB_SIZE <= CAAM_BLOB_MAX_LEN); + +static int trusted_caam_seal(struct trusted_key_payload *p, char *datablob) +{ + int ret; + struct caam_blob_info info = { + .input = p->key, .input_len = p->key_len, + .output = p->blob, .output_len = MAX_BLOB_SIZE, + .key_mod = KEYMOD, .key_mod_len = sizeof(KEYMOD) - 1, + }; + + ret = caam_encap_blob(blobifier, &info); + if (ret) + return ret; + + p->blob_len = info.output_len; + return 0; +} + +static int trusted_caam_unseal(struct trusted_key_payload *p, char *datablob) +{ + int ret; + struct caam_blob_info info = { + .input = p->blob, .input_len = p->blob_len, + .output = p->key, .output_len = MAX_KEY_SIZE, + .key_mod = KEYMOD, .key_mod_len = sizeof(KEYMOD) - 1, + }; + + ret = caam_decap_blob(blobifier, &info); + if (ret) + return ret; + + p->key_len = info.output_len; + return 0; +} + +static int trusted_caam_init(void) +{ + int ret; + + blobifier = caam_blob_gen_init(); + if (IS_ERR(blobifier)) + return PTR_ERR(blobifier); + + ret = register_key_type(&key_type_trusted); + if (ret) + caam_blob_gen_exit(blobifier); + + return ret; +} + +static void trusted_caam_exit(void) +{ + unregister_key_type(&key_type_trusted); + caam_blob_gen_exit(blobifier); +} + +struct trusted_key_ops trusted_key_caam_ops = { + .migratable = 0, /* non-migratable */ + .init = trusted_caam_init, + .seal = trusted_caam_seal, + .unseal = trusted_caam_unseal, + .exit = trusted_caam_exit, +}; diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c new file mode 100644 index 000000000000..c6fc50d67214 --- /dev/null +++ b/security/keys/trusted-keys/trusted_core.c @@ -0,0 +1,397 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2010 IBM Corporation + * Copyright (c) 2019-2021, Linaro Limited + * + * See Documentation/security/keys/trusted-encrypted.rst + */ + +#include <keys/user-type.h> +#include <keys/trusted-type.h> +#include <keys/trusted_tee.h> +#include <keys/trusted_caam.h> +#include <keys/trusted_tpm.h> +#include <linux/capability.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/key-type.h> +#include <linux/module.h> +#include <linux/parser.h> +#include <linux/random.h> +#include <linux/rcupdate.h> +#include <linux/slab.h> +#include <linux/static_call.h> +#include <linux/string.h> +#include <linux/uaccess.h> + +static char *trusted_rng = "default"; +module_param_named(rng, trusted_rng, charp, 0); +MODULE_PARM_DESC(rng, "Select trusted key RNG"); + +static char *trusted_key_source; +module_param_named(source, trusted_key_source, charp, 0); +MODULE_PARM_DESC(source, "Select trusted keys source (tpm, tee or caam)"); + +static const struct trusted_key_source trusted_key_sources[] = { +#if defined(CONFIG_TRUSTED_KEYS_TPM) + { "tpm", &trusted_key_tpm_ops }, +#endif +#if defined(CONFIG_TRUSTED_KEYS_TEE) + { "tee", &trusted_key_tee_ops }, +#endif +#if defined(CONFIG_TRUSTED_KEYS_CAAM) + { "caam", &trusted_key_caam_ops }, +#endif +}; + +DEFINE_STATIC_CALL_NULL(trusted_key_init, *trusted_key_sources[0].ops->init); +DEFINE_STATIC_CALL_NULL(trusted_key_seal, *trusted_key_sources[0].ops->seal); +DEFINE_STATIC_CALL_NULL(trusted_key_unseal, + *trusted_key_sources[0].ops->unseal); +DEFINE_STATIC_CALL_NULL(trusted_key_get_random, + *trusted_key_sources[0].ops->get_random); +DEFINE_STATIC_CALL_NULL(trusted_key_exit, *trusted_key_sources[0].ops->exit); +static unsigned char migratable; + +enum { + Opt_err, + Opt_new, Opt_load, Opt_update, +}; + +static const match_table_t key_tokens = { + {Opt_new, "new"}, + {Opt_load, "load"}, + {Opt_update, "update"}, + {Opt_err, NULL} +}; + +/* + * datablob_parse - parse the keyctl data and fill in the + * payload structure + * + * On success returns 0, otherwise -EINVAL. + */ +static int datablob_parse(char **datablob, struct trusted_key_payload *p) +{ + 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 = 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 = Opt_load; + break; + case Opt_update: + ret = Opt_update; + break; + case Opt_err: + return -EINVAL; + } + return ret; +} + +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) + goto err; + p = kzalloc(sizeof(*p), GFP_KERNEL); + if (!p) + goto err; + + p->migratable = migratable; +err: + 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; + size_t datalen = prep->datalen; + char *datablob, *orig_datablob; + int ret = 0; + int key_cmd; + size_t key_len; + + if (datalen <= 0 || datalen > 32767 || !prep->data) + return -EINVAL; + + orig_datablob = datablob = kmalloc(datalen + 1, GFP_KERNEL); + if (!datablob) + return -ENOMEM; + memcpy(datablob, prep->data, datalen); + datablob[datalen] = '\0'; + + payload = trusted_payload_alloc(key); + if (!payload) { + ret = -ENOMEM; + goto out; + } + + key_cmd = datablob_parse(&datablob, payload); + if (key_cmd < 0) { + ret = key_cmd; + goto out; + } + + dump_payload(payload); + + switch (key_cmd) { + case Opt_load: + ret = static_call(trusted_key_unseal)(payload, datablob); + dump_payload(payload); + if (ret < 0) + pr_info("key_unseal failed (%d)\n", ret); + break; + case Opt_new: + key_len = payload->key_len; + ret = static_call(trusted_key_get_random)(payload->key, + key_len); + if (ret < 0) + goto out; + + if (ret != key_len) { + pr_info("key_create failed (%d)\n", ret); + ret = -EIO; + goto out; + } + + ret = static_call(trusted_key_seal)(payload, datablob); + if (ret < 0) + pr_info("key_seal failed (%d)\n", ret); + break; + default: + ret = -EINVAL; + } +out: + kfree_sensitive(orig_datablob); + if (!ret) + rcu_assign_keypointer(key, payload); + else + kfree_sensitive(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); + kfree_sensitive(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; + size_t datalen = prep->datalen; + char *datablob, *orig_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; + + orig_datablob = datablob = kmalloc(datalen + 1, GFP_KERNEL); + if (!datablob) + return -ENOMEM; + + 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); + if (ret != Opt_update) { + ret = -EINVAL; + kfree_sensitive(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 = static_call(trusted_key_seal)(new_p, datablob); + if (ret < 0) { + pr_info("key_seal failed (%d)\n", ret); + kfree_sensitive(new_p); + goto out; + } + + rcu_assign_keypointer(key, new_p); + call_rcu(&p->rcu, trusted_rcu_free); +out: + kfree_sensitive(orig_datablob); + 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 *buffer, + size_t buflen) +{ + const struct trusted_key_payload *p; + char *bufp; + int i; + + p = dereference_key_locked(key); + if (!p) + return -EINVAL; + + if (buffer && buflen >= 2 * p->blob_len) { + bufp = buffer; + for (i = 0; i < p->blob_len; i++) + bufp = hex_byte_pack(bufp, p->blob[i]); + } + return 2 * p->blob_len; +} + +/* + * trusted_destroy - clear and free the key's payload + */ +static void trusted_destroy(struct key *key) +{ + kfree_sensitive(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 int kernel_get_random(unsigned char *key, size_t key_len) +{ + return get_random_bytes_wait(key, key_len) ?: key_len; +} + +static int __init init_trusted(void) +{ + int (*get_random)(unsigned char *key, size_t key_len); + int i, ret = 0; + + for (i = 0; i < ARRAY_SIZE(trusted_key_sources); i++) { + if (trusted_key_source && + strncmp(trusted_key_source, trusted_key_sources[i].name, + strlen(trusted_key_sources[i].name))) + continue; + + /* + * We always support trusted.rng="kernel" and "default" as + * well as trusted.rng=$trusted.source if the trust source + * defines its own get_random callback. + */ + get_random = trusted_key_sources[i].ops->get_random; + if (trusted_rng && strcmp(trusted_rng, "default")) { + if (!strcmp(trusted_rng, "kernel")) { + get_random = kernel_get_random; + } else if (strcmp(trusted_rng, trusted_key_sources[i].name) || + !get_random) { + pr_warn("Unsupported RNG. Supported: kernel"); + if (get_random) + pr_cont(", %s", trusted_key_sources[i].name); + pr_cont(", default\n"); + return -EINVAL; + } + } + + if (!get_random) + get_random = kernel_get_random; + + static_call_update(trusted_key_init, + trusted_key_sources[i].ops->init); + static_call_update(trusted_key_seal, + trusted_key_sources[i].ops->seal); + static_call_update(trusted_key_unseal, + trusted_key_sources[i].ops->unseal); + static_call_update(trusted_key_get_random, + get_random); + static_call_update(trusted_key_exit, + trusted_key_sources[i].ops->exit); + migratable = trusted_key_sources[i].ops->migratable; + + ret = static_call(trusted_key_init)(); + if (!ret) + break; + } + + /* + * encrypted_keys.ko depends on successful load of this module even if + * trusted key implementation is not found. + */ + if (ret == -ENODEV) + return 0; + + return ret; +} + +static void __exit cleanup_trusted(void) +{ + static_call_cond(trusted_key_exit)(); +} + +late_initcall(init_trusted); +module_exit(cleanup_trusted); + +MODULE_LICENSE("GPL"); diff --git a/security/keys/trusted-keys/trusted_tee.c b/security/keys/trusted-keys/trusted_tee.c new file mode 100644 index 000000000000..c8626686ee1b --- /dev/null +++ b/security/keys/trusted-keys/trusted_tee.c @@ -0,0 +1,313 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019-2021 Linaro Ltd. + * + * Author: + * Sumit Garg <sumit.garg@linaro.org> + */ + +#include <linux/err.h> +#include <linux/key-type.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/tee_drv.h> +#include <linux/uuid.h> + +#include <keys/trusted_tee.h> + +#define DRIVER_NAME "trusted-key-tee" + +/* + * Get random data for symmetric key + * + * [out] memref[0] Random data + */ +#define TA_CMD_GET_RANDOM 0x0 + +/* + * Seal trusted key using hardware unique key + * + * [in] memref[0] Plain key + * [out] memref[1] Sealed key datablob + */ +#define TA_CMD_SEAL 0x1 + +/* + * Unseal trusted key using hardware unique key + * + * [in] memref[0] Sealed key datablob + * [out] memref[1] Plain key + */ +#define TA_CMD_UNSEAL 0x2 + +/** + * struct trusted_key_tee_private - TEE Trusted key private data + * @dev: TEE based Trusted key device. + * @ctx: TEE context handler. + * @session_id: Trusted key TA session identifier. + * @shm_pool: Memory pool shared with TEE device. + */ +struct trusted_key_tee_private { + struct device *dev; + struct tee_context *ctx; + u32 session_id; + struct tee_shm *shm_pool; +}; + +static struct trusted_key_tee_private pvt_data; + +/* + * Have the TEE seal(encrypt) the symmetric key + */ +static int trusted_tee_seal(struct trusted_key_payload *p, char *datablob) +{ + int ret; + struct tee_ioctl_invoke_arg inv_arg; + struct tee_param param[4]; + struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL; + + memset(&inv_arg, 0, sizeof(inv_arg)); + memset(¶m, 0, sizeof(param)); + + reg_shm_in = tee_shm_register_kernel_buf(pvt_data.ctx, p->key, + p->key_len); + if (IS_ERR(reg_shm_in)) { + dev_err(pvt_data.dev, "key shm register failed\n"); + return PTR_ERR(reg_shm_in); + } + + reg_shm_out = tee_shm_register_kernel_buf(pvt_data.ctx, p->blob, + sizeof(p->blob)); + if (IS_ERR(reg_shm_out)) { + dev_err(pvt_data.dev, "blob shm register failed\n"); + ret = PTR_ERR(reg_shm_out); + goto out; + } + + inv_arg.func = TA_CMD_SEAL; + inv_arg.session = pvt_data.session_id; + inv_arg.num_params = 4; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT; + param[0].u.memref.shm = reg_shm_in; + param[0].u.memref.size = p->key_len; + param[0].u.memref.shm_offs = 0; + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT; + param[1].u.memref.shm = reg_shm_out; + param[1].u.memref.size = sizeof(p->blob); + param[1].u.memref.shm_offs = 0; + + ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param); + if ((ret < 0) || (inv_arg.ret != 0)) { + dev_err(pvt_data.dev, "TA_CMD_SEAL invoke err: %x\n", + inv_arg.ret); + ret = -EFAULT; + } else { + p->blob_len = param[1].u.memref.size; + } + +out: + if (reg_shm_out) + tee_shm_free(reg_shm_out); + if (reg_shm_in) + tee_shm_free(reg_shm_in); + + return ret; +} + +/* + * Have the TEE unseal(decrypt) the symmetric key + */ +static int trusted_tee_unseal(struct trusted_key_payload *p, char *datablob) +{ + int ret; + struct tee_ioctl_invoke_arg inv_arg; + struct tee_param param[4]; + struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL; + + memset(&inv_arg, 0, sizeof(inv_arg)); + memset(¶m, 0, sizeof(param)); + + reg_shm_in = tee_shm_register_kernel_buf(pvt_data.ctx, p->blob, + p->blob_len); + if (IS_ERR(reg_shm_in)) { + dev_err(pvt_data.dev, "blob shm register failed\n"); + return PTR_ERR(reg_shm_in); + } + + reg_shm_out = tee_shm_register_kernel_buf(pvt_data.ctx, p->key, + sizeof(p->key)); + if (IS_ERR(reg_shm_out)) { + dev_err(pvt_data.dev, "key shm register failed\n"); + ret = PTR_ERR(reg_shm_out); + goto out; + } + + inv_arg.func = TA_CMD_UNSEAL; + inv_arg.session = pvt_data.session_id; + inv_arg.num_params = 4; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT; + param[0].u.memref.shm = reg_shm_in; + param[0].u.memref.size = p->blob_len; + param[0].u.memref.shm_offs = 0; + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT; + param[1].u.memref.shm = reg_shm_out; + param[1].u.memref.size = sizeof(p->key); + param[1].u.memref.shm_offs = 0; + + ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param); + if ((ret < 0) || (inv_arg.ret != 0)) { + dev_err(pvt_data.dev, "TA_CMD_UNSEAL invoke err: %x\n", + inv_arg.ret); + ret = -EFAULT; + } else { + p->key_len = param[1].u.memref.size; + } + +out: + if (reg_shm_out) + tee_shm_free(reg_shm_out); + if (reg_shm_in) + tee_shm_free(reg_shm_in); + + return ret; +} + +/* + * Have the TEE generate random symmetric key + */ +static int trusted_tee_get_random(unsigned char *key, size_t key_len) +{ + int ret; + struct tee_ioctl_invoke_arg inv_arg; + struct tee_param param[4]; + struct tee_shm *reg_shm = NULL; + + memset(&inv_arg, 0, sizeof(inv_arg)); + memset(¶m, 0, sizeof(param)); + + reg_shm = tee_shm_register_kernel_buf(pvt_data.ctx, key, key_len); + if (IS_ERR(reg_shm)) { + dev_err(pvt_data.dev, "key shm register failed\n"); + return PTR_ERR(reg_shm); + } + + inv_arg.func = TA_CMD_GET_RANDOM; + inv_arg.session = pvt_data.session_id; + inv_arg.num_params = 4; + + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT; + param[0].u.memref.shm = reg_shm; + param[0].u.memref.size = key_len; + param[0].u.memref.shm_offs = 0; + + ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param); + if ((ret < 0) || (inv_arg.ret != 0)) { + dev_err(pvt_data.dev, "TA_CMD_GET_RANDOM invoke err: %x\n", + inv_arg.ret); + ret = -EFAULT; + } else { + ret = param[0].u.memref.size; + } + + tee_shm_free(reg_shm); + + return ret; +} + +static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) +{ + if (ver->impl_id == TEE_IMPL_ID_OPTEE) + return 1; + else + return 0; +} + +static int trusted_key_probe(struct device *dev) +{ + struct tee_client_device *rng_device = to_tee_client_device(dev); + int ret; + struct tee_ioctl_open_session_arg sess_arg; + + memset(&sess_arg, 0, sizeof(sess_arg)); + + pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, + NULL); + if (IS_ERR(pvt_data.ctx)) + return -ENODEV; + + memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN); + sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL; + sess_arg.num_params = 0; + + ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL); + if ((ret < 0) || (sess_arg.ret != 0)) { + dev_err(dev, "tee_client_open_session failed, err: %x\n", + sess_arg.ret); + ret = -EINVAL; + goto out_ctx; + } + pvt_data.session_id = sess_arg.session; + + ret = register_key_type(&key_type_trusted); + if (ret < 0) + goto out_sess; + + pvt_data.dev = dev; + + return 0; + +out_sess: + tee_client_close_session(pvt_data.ctx, pvt_data.session_id); +out_ctx: + tee_client_close_context(pvt_data.ctx); + + return ret; +} + +static int trusted_key_remove(struct device *dev) +{ + unregister_key_type(&key_type_trusted); + tee_client_close_session(pvt_data.ctx, pvt_data.session_id); + tee_client_close_context(pvt_data.ctx); + + return 0; +} + +static const struct tee_client_device_id trusted_key_id_table[] = { + {UUID_INIT(0xf04a0fe7, 0x1f5d, 0x4b9b, + 0xab, 0xf7, 0x61, 0x9b, 0x85, 0xb4, 0xce, 0x8c)}, + {} +}; +MODULE_DEVICE_TABLE(tee, trusted_key_id_table); + +static struct tee_client_driver trusted_key_driver = { + .id_table = trusted_key_id_table, + .driver = { + .name = DRIVER_NAME, + .bus = &tee_bus_type, + .probe = trusted_key_probe, + .remove = trusted_key_remove, + }, +}; + +static int trusted_tee_init(void) +{ + return driver_register(&trusted_key_driver.driver); +} + +static void trusted_tee_exit(void) +{ + driver_unregister(&trusted_key_driver.driver); +} + +struct trusted_key_ops trusted_key_tee_ops = { + .migratable = 0, /* non-migratable */ + .init = trusted_tee_init, + .seal = trusted_tee_seal, + .unseal = trusted_tee_unseal, + .get_random = trusted_tee_get_random, + .exit = trusted_tee_exit, +}; diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c index d2c5ec1e040b..aa108bea6739 100644 --- a/security/keys/trusted-keys/trusted_tpm1.c +++ b/security/keys/trusted-keys/trusted_tpm1.c @@ -1,29 +1,22 @@ // SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2010 IBM Corporation - * - * Author: - * David Safford <safford@us.ibm.com> + * Copyright (c) 2019-2021, Linaro Limited * * 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 <crypto/sha1.h> #include <linux/tpm.h> #include <linux/tpm_command.h> @@ -63,12 +56,12 @@ static int TSS_sha1(const unsigned char *data, unsigned int datalen, sdesc = init_sdesc(hashalg); if (IS_ERR(sdesc)) { - pr_info("trusted_key: can't alloc %s\n", hash_alg); + pr_info("can't alloc %s\n", hash_alg); return PTR_ERR(sdesc); } ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest); - kzfree(sdesc); + kfree_sensitive(sdesc); return ret; } @@ -83,7 +76,7 @@ static int TSS_rawhmac(unsigned char *digest, const unsigned char *key, sdesc = init_sdesc(hmacalg); if (IS_ERR(sdesc)) { - pr_info("trusted_key: can't alloc %s\n", hmac_alg); + pr_info("can't alloc %s\n", hmac_alg); return PTR_ERR(sdesc); } @@ -112,7 +105,7 @@ static int TSS_rawhmac(unsigned char *digest, const unsigned char *key, if (!ret) ret = crypto_shash_final(&sdesc->shash, digest); out: - kzfree(sdesc); + kfree_sensitive(sdesc); return ret; } @@ -136,7 +129,7 @@ int TSS_authhmac(unsigned char *digest, const unsigned char *key, sdesc = init_sdesc(hashalg); if (IS_ERR(sdesc)) { - pr_info("trusted_key: can't alloc %s\n", hash_alg); + pr_info("can't alloc %s\n", hash_alg); return PTR_ERR(sdesc); } @@ -166,7 +159,7 @@ int TSS_authhmac(unsigned char *digest, const unsigned char *key, paramdigest, TPM_NONCE_SIZE, h1, TPM_NONCE_SIZE, h2, 1, &c, 0, 0); out: - kzfree(sdesc); + kfree_sensitive(sdesc); return ret; } EXPORT_SYMBOL_GPL(TSS_authhmac); @@ -212,7 +205,7 @@ int TSS_checkhmac1(unsigned char *buffer, sdesc = init_sdesc(hashalg); if (IS_ERR(sdesc)) { - pr_info("trusted_key: can't alloc %s\n", hash_alg); + pr_info("can't alloc %s\n", hash_alg); return PTR_ERR(sdesc); } ret = crypto_shash_init(&sdesc->shash); @@ -251,7 +244,7 @@ int TSS_checkhmac1(unsigned char *buffer, if (memcmp(testhmac, authdata, SHA1_DIGEST_SIZE)) ret = -EINVAL; out: - kzfree(sdesc); + kfree_sensitive(sdesc); return ret; } EXPORT_SYMBOL_GPL(TSS_checkhmac1); @@ -305,7 +298,7 @@ static int TSS_checkhmac2(unsigned char *buffer, sdesc = init_sdesc(hashalg); if (IS_ERR(sdesc)) { - pr_info("trusted_key: can't alloc %s\n", hash_alg); + pr_info("can't alloc %s\n", hash_alg); return PTR_ERR(sdesc); } ret = crypto_shash_init(&sdesc->shash); @@ -353,7 +346,7 @@ static int TSS_checkhmac2(unsigned char *buffer, if (memcmp(testhmac2, authdata2, SHA1_DIGEST_SIZE)) ret = -EINVAL; out: - kzfree(sdesc); + kfree_sensitive(sdesc); return ret; } @@ -403,9 +396,12 @@ static int osap(struct tpm_buf *tb, struct osapsess *s, int ret; ret = tpm_get_random(chip, ononce, TPM_NONCE_SIZE); - if (ret != TPM_NONCE_SIZE) + if (ret < 0) return ret; + if (ret != TPM_NONCE_SIZE) + return -EIO; + tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OSAP); tpm_buf_append_u16(tb, type); tpm_buf_append_u32(tb, handle); @@ -496,8 +492,14 @@ static int tpm_seal(struct tpm_buf *tb, uint16_t keytype, goto out; ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE); - if (ret != TPM_NONCE_SIZE) + if (ret < 0) goto out; + + if (ret != TPM_NONCE_SIZE) { + ret = -EIO; + goto out; + } + ordinal = htonl(TPM_ORD_SEAL); datsize = htonl(datalen); pcrsize = htonl(pcrinfosize); @@ -563,7 +565,7 @@ static int tpm_seal(struct tpm_buf *tb, uint16_t keytype, *bloblen = storedsize; } out: - kzfree(td); + kfree_sensitive(td); return ret; } @@ -590,20 +592,23 @@ static int tpm_unseal(struct tpm_buf *tb, /* sessions for unsealing key and data */ ret = oiap(tb, &authhandle1, enonce1); if (ret < 0) { - pr_info("trusted_key: oiap failed (%d)\n", ret); + pr_info("oiap failed (%d)\n", ret); return ret; } ret = oiap(tb, &authhandle2, enonce2); if (ret < 0) { - pr_info("trusted_key: oiap failed (%d)\n", ret); + pr_info("oiap failed (%d)\n", ret); return ret; } ordinal = htonl(TPM_ORD_UNSEAL); 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); + if (ret < 0) return ret; + + if (ret != TPM_NONCE_SIZE) { + pr_info("tpm_get_random failed (%d)\n", ret); + return -EIO; } ret = TSS_authhmac(authdata1, keyauth, TPM_NONCE_SIZE, enonce1, nonceodd, cont, sizeof(uint32_t), @@ -631,7 +636,7 @@ static int tpm_unseal(struct tpm_buf *tb, ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE); if (ret < 0) { - pr_info("trusted_key: authhmac failed (%d)\n", ret); + pr_info("authhmac failed (%d)\n", ret); return ret; } @@ -643,7 +648,7 @@ static int tpm_unseal(struct tpm_buf *tb, *datalen, TPM_DATA_OFFSET + sizeof(uint32_t), 0, 0); if (ret < 0) { - pr_info("trusted_key: TSS_checkhmac2 failed (%d)\n", ret); + pr_info("TSS_checkhmac2 failed (%d)\n", ret); return ret; } memcpy(data, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), *datalen); @@ -670,7 +675,7 @@ static int key_seal(struct trusted_key_payload *p, 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); + pr_info("srkseal failed (%d)\n", ret); tpm_buf_destroy(&tb); return ret; @@ -692,7 +697,7 @@ static int key_unseal(struct trusted_key_payload *p, 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); + pr_info("srkunseal failed (%d)\n", ret); else /* pull migratable flag out of sealed key */ p->migratable = p->key[--p->key_len]; @@ -703,7 +708,6 @@ static int key_unseal(struct trusted_key_payload *p, enum { Opt_err, - Opt_new, Opt_load, Opt_update, Opt_keyhandle, Opt_keyauth, Opt_blobauth, Opt_pcrinfo, Opt_pcrlock, Opt_migratable, Opt_hash, @@ -712,9 +716,6 @@ enum { }; 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"}, @@ -748,6 +749,9 @@ static int getoptions(char *c, struct trusted_key_payload *pay, opt->hash = tpm2 ? HASH_ALGO_SHA256 : HASH_ALGO_SHA1; + if (!c) + return 0; + while ((p = strsep(&c, " \t"))) { if (*p == '\0' || *p == ' ' || *p == '\t') continue; @@ -781,17 +785,37 @@ static int getoptions(char *c, struct trusted_key_payload *pay, 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; + /* + * TPM 1.2 authorizations are sha1 hashes passed in as + * hex strings. TPM 2.0 authorizations are simple + * passwords (although it can take a hash as well) + */ + opt->blobauth_len = strlen(args[0].from); + + if (opt->blobauth_len == 2 * TPM_DIGEST_SIZE) { + res = hex2bin(opt->blobauth, args[0].from, + TPM_DIGEST_SIZE); + if (res < 0) + return -EINVAL; + + opt->blobauth_len = TPM_DIGEST_SIZE; + break; + } + + if (tpm2 && opt->blobauth_len <= sizeof(opt->blobauth)) { + memcpy(opt->blobauth, args[0].from, + opt->blobauth_len); + break; + } + + return -EINVAL; + break; + case Opt_migratable: if (*args[0].from == '0') pay->migratable = 0; - else + else if (*args[0].from != '1') return -EINVAL; break; case Opt_pcrlock: @@ -812,7 +836,7 @@ static int getoptions(char *c, struct trusted_key_payload *pay, 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"); + pr_info("TPM 1.x only supports SHA-1.\n"); return -EINVAL; } break; @@ -841,71 +865,6 @@ static int getoptions(char *c, struct trusted_key_payload *pay, 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; @@ -926,258 +885,99 @@ static struct trusted_key_options *trusted_options_alloc(void) return options; } -static struct trusted_key_payload *trusted_payload_alloc(struct key *key) +static int trusted_tpm_seal(struct trusted_key_payload *p, char *datablob) { - 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) + options = trusted_options_alloc(); + if (!options) 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; + ret = getoptions(datablob, p, options); + if (ret < 0) goto out; - } + dump_options(options); - key_cmd = datablob_parse(datablob, payload, options); - if (key_cmd < 0) { - ret = key_cmd; + if (!options->keyhandle && !tpm2) { + ret = -EINVAL; goto out; } - if (!options->keyhandle) { - ret = -EINVAL; + if (tpm2) + ret = tpm2_seal_trusted(chip, p, options); + else + ret = key_seal(p, options); + if (ret < 0) { + pr_info("key_seal failed (%d)\n", ret); goto out; } - dump_payload(payload); - dump_options(options); - - switch (key_cmd) { - case Opt_load: - if (tpm2) - ret = tpm2_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); + if (options->pcrlock) { + ret = pcrlock(options->pcrlock); + if (ret < 0) { + pr_info("pcrlock failed (%d)\n", ret); goto out; } - if (tpm2) - ret = tpm2_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); + kfree_sensitive(options); return ret; } -static void trusted_rcu_free(struct rcu_head *rcu) +static int trusted_tpm_unseal(struct trusted_key_payload *p, char *datablob) { - 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; + struct trusted_key_options *options = NULL; int ret = 0; + int tpm2; - 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; + tpm2 = tpm_is_tpm2(chip); + if (tpm2 < 0) + return tpm2; - datablob = kmalloc(datalen + 1, GFP_KERNEL); - if (!datablob) + options = trusted_options_alloc(); + if (!options) 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); + ret = getoptions(datablob, p, options); + if (ret < 0) goto out; - } + dump_options(options); - if (!new_o->keyhandle) { + if (!options->keyhandle && !tpm2) { 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); + if (tpm2) + ret = tpm2_unseal_trusted(chip, p, options); + else + ret = key_unseal(p, options); + if (ret < 0) + pr_info("key_unseal failed (%d)\n", ret); - 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 (options->pcrlock) { + ret = pcrlock(options->pcrlock); if (ret < 0) { - pr_info("trusted_key: pcrlock failed (%d)\n", ret); - kzfree(new_p); + pr_info("pcrlock failed (%d)\n", ret); goto out; } } - rcu_assign_keypointer(key, new_p); - call_rcu(&p->rcu, trusted_rcu_free); out: - kzfree(datablob); - kzfree(new_o); + kfree_sensitive(options); 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) +static int trusted_tpm_get_random(unsigned char *key, size_t key_len) { - 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]); + return tpm_get_random(chip, key, key_len); } -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) @@ -1192,14 +992,14 @@ static int __init trusted_shash_alloc(void) hmacalg = crypto_alloc_shash(hmac_alg, 0, 0); if (IS_ERR(hmacalg)) { - pr_info("trusted_key: could not allocate crypto %s\n", + pr_info("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", + pr_info("could not allocate crypto %s\n", hash_alg); ret = PTR_ERR(hashalg); goto hashalg_fail; @@ -1227,16 +1027,13 @@ static int __init init_digests(void) return 0; } -static int __init init_trusted(void) +static int __init trusted_tpm_init(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; + return -ENODEV; ret = init_digests(); if (ret < 0) @@ -1257,7 +1054,7 @@ err_put: return ret; } -static void __exit cleanup_trusted(void) +static void trusted_tpm_exit(void) { if (chip) { put_device(&chip->dev); @@ -1267,7 +1064,11 @@ static void __exit cleanup_trusted(void) } } -late_initcall(init_trusted); -module_exit(cleanup_trusted); - -MODULE_LICENSE("GPL"); +struct trusted_key_ops trusted_key_tpm_ops = { + .migratable = 1, /* migratable by default */ + .init = trusted_tpm_init, + .seal = trusted_tpm_seal, + .unseal = trusted_tpm_unseal, + .get_random = trusted_tpm_get_random, + .exit = trusted_tpm_exit, +}; diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c index 08ec7f48f01d..2b2c8eb258d5 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -4,6 +4,8 @@ * Copyright (C) 2014 Intel Corporation */ +#include <linux/asn1_encoder.h> +#include <linux/oid_registry.h> #include <linux/string.h> #include <linux/err.h> #include <linux/tpm.h> @@ -12,6 +14,10 @@ #include <keys/trusted-type.h> #include <keys/trusted_tpm.h> +#include <asm/unaligned.h> + +#include "tpm2key.asn1.h" + static struct tpm2_hash tpm2_hash_map[] = { {HASH_ALGO_SHA1, TPM_ALG_SHA1}, {HASH_ALGO_SHA256, TPM_ALG_SHA256}, @@ -20,6 +26,165 @@ static struct tpm2_hash tpm2_hash_map[] = { {HASH_ALGO_SM3_256, TPM_ALG_SM3_256}, }; +static u32 tpm2key_oid[] = { 2, 23, 133, 10, 1, 5 }; + +static int tpm2_key_encode(struct trusted_key_payload *payload, + struct trusted_key_options *options, + u8 *src, u32 len) +{ + const int SCRATCH_SIZE = PAGE_SIZE; + u8 *scratch = kmalloc(SCRATCH_SIZE, GFP_KERNEL); + u8 *work = scratch, *work1; + u8 *end_work = scratch + SCRATCH_SIZE; + u8 *priv, *pub; + u16 priv_len, pub_len; + + priv_len = get_unaligned_be16(src) + 2; + priv = src; + + src += priv_len; + + pub_len = get_unaligned_be16(src) + 2; + pub = src; + + if (!scratch) + return -ENOMEM; + + work = asn1_encode_oid(work, end_work, tpm2key_oid, + asn1_oid_len(tpm2key_oid)); + + if (options->blobauth_len == 0) { + unsigned char bool[3], *w = bool; + /* tag 0 is emptyAuth */ + w = asn1_encode_boolean(w, w + sizeof(bool), true); + if (WARN(IS_ERR(w), "BUG: Boolean failed to encode")) + return PTR_ERR(w); + work = asn1_encode_tag(work, end_work, 0, bool, w - bool); + } + + /* + * Assume both octet strings will encode to a 2 byte definite length + * + * Note: For a well behaved TPM, this warning should never + * trigger, so if it does there's something nefarious going on + */ + if (WARN(work - scratch + pub_len + priv_len + 14 > SCRATCH_SIZE, + "BUG: scratch buffer is too small")) + return -EINVAL; + + work = asn1_encode_integer(work, end_work, options->keyhandle); + work = asn1_encode_octet_string(work, end_work, pub, pub_len); + work = asn1_encode_octet_string(work, end_work, priv, priv_len); + + work1 = payload->blob; + work1 = asn1_encode_sequence(work1, work1 + sizeof(payload->blob), + scratch, work - scratch); + if (WARN(IS_ERR(work1), "BUG: ASN.1 encoder failed")) + return PTR_ERR(work1); + + return work1 - payload->blob; +} + +struct tpm2_key_context { + u32 parent; + const u8 *pub; + u32 pub_len; + const u8 *priv; + u32 priv_len; +}; + +static int tpm2_key_decode(struct trusted_key_payload *payload, + struct trusted_key_options *options, + u8 **buf) +{ + int ret; + struct tpm2_key_context ctx; + u8 *blob; + + memset(&ctx, 0, sizeof(ctx)); + + ret = asn1_ber_decoder(&tpm2key_decoder, &ctx, payload->blob, + payload->blob_len); + if (ret < 0) + return ret; + + if (ctx.priv_len + ctx.pub_len > MAX_BLOB_SIZE) + return -EINVAL; + + blob = kmalloc(ctx.priv_len + ctx.pub_len + 4, GFP_KERNEL); + if (!blob) + return -ENOMEM; + + *buf = blob; + options->keyhandle = ctx.parent; + + memcpy(blob, ctx.priv, ctx.priv_len); + blob += ctx.priv_len; + + memcpy(blob, ctx.pub, ctx.pub_len); + + return 0; +} + +int tpm2_key_parent(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct tpm2_key_context *ctx = context; + const u8 *v = value; + int i; + + ctx->parent = 0; + for (i = 0; i < vlen; i++) { + ctx->parent <<= 8; + ctx->parent |= v[i]; + } + + return 0; +} + +int tpm2_key_type(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + enum OID oid = look_up_OID(value, vlen); + + if (oid != OID_TPMSealedData) { + char buffer[50]; + + sprint_oid(value, vlen, buffer, sizeof(buffer)); + pr_debug("OID is \"%s\" which is not TPMSealedData\n", + buffer); + return -EINVAL; + } + + return 0; +} + +int tpm2_key_pub(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct tpm2_key_context *ctx = context; + + ctx->pub = value; + ctx->pub_len = vlen; + + return 0; +} + +int tpm2_key_priv(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct tpm2_key_context *ctx = context; + + ctx->priv = value; + ctx->priv_len = vlen; + + return 0; +} + /** * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer. * @@ -63,9 +228,10 @@ int tpm2_seal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options) { - unsigned int blob_len; + int blob_len = 0; struct tpm_buf buf; u32 hash; + u32 flags; int i; int rc; @@ -79,10 +245,19 @@ int tpm2_seal_trusted(struct tpm_chip *chip, if (i == ARRAY_SIZE(tpm2_hash_map)) return -EINVAL; - rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE); + if (!options->keyhandle) + return -EINVAL; + + rc = tpm_try_get_ops(chip); if (rc) return rc; + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE); + if (rc) { + tpm_put_ops(chip); + return rc; + } + tpm_buf_append_u32(&buf, options->keyhandle); tpm2_buf_append_auth(&buf, TPM2_RS_PW, NULL /* nonce */, 0, @@ -91,29 +266,32 @@ int tpm2_seal_trusted(struct tpm_chip *chip, TPM_DIGEST_SIZE); /* sensitive */ - tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1); + tpm_buf_append_u16(&buf, 4 + options->blobauth_len + payload->key_len); - tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE); - tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE); - tpm_buf_append_u16(&buf, payload->key_len + 1); + tpm_buf_append_u16(&buf, options->blobauth_len); + if (options->blobauth_len) + tpm_buf_append(&buf, options->blobauth, options->blobauth_len); + + tpm_buf_append_u16(&buf, payload->key_len); tpm_buf_append(&buf, payload->key, payload->key_len); - tpm_buf_append_u8(&buf, payload->migratable); /* public */ tpm_buf_append_u16(&buf, 14 + options->policydigest_len); tpm_buf_append_u16(&buf, TPM_ALG_KEYEDHASH); tpm_buf_append_u16(&buf, hash); + /* key properties */ + flags = 0; + flags |= options->policydigest_len ? 0 : TPM2_OA_USER_WITH_AUTH; + flags |= payload->migratable ? 0 : (TPM2_OA_FIXED_TPM | + TPM2_OA_FIXED_PARENT); + tpm_buf_append_u32(&buf, flags); + /* policy */ - if (options->policydigest_len) { - tpm_buf_append_u32(&buf, 0); - tpm_buf_append_u16(&buf, options->policydigest_len); + tpm_buf_append_u16(&buf, options->policydigest_len); + if (options->policydigest_len) tpm_buf_append(&buf, options->policydigest, options->policydigest_len); - } else { - tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH); - tpm_buf_append_u16(&buf, 0); - } /* public parameters */ tpm_buf_append_u16(&buf, TPM_ALG_NULL); @@ -130,7 +308,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip, goto out; } - rc = tpm_send(chip, buf.data, tpm_buf_length(&buf)); + rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data"); if (rc) goto out; @@ -144,8 +322,9 @@ int tpm2_seal_trusted(struct tpm_chip *chip, goto out; } - memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len); - payload->blob_len = blob_len; + blob_len = tpm2_key_encode(payload, options, + &buf.data[TPM_HEADER_SIZE + 4], + blob_len); out: tpm_buf_destroy(&buf); @@ -156,7 +335,12 @@ out: else rc = -EPERM; } + if (blob_len < 0) + rc = blob_len; + else + payload->blob_len = blob_len; + tpm_put_ops(chip); return rc; } @@ -182,13 +366,45 @@ static int tpm2_load_cmd(struct tpm_chip *chip, unsigned int private_len; unsigned int public_len; unsigned int blob_len; + u8 *blob, *pub; int rc; + u32 attrs; + + rc = tpm2_key_decode(payload, options, &blob); + if (rc) { + /* old form */ + blob = payload->blob; + payload->old_format = 1; + } - private_len = be16_to_cpup((__be16 *) &payload->blob[0]); - if (private_len > (payload->blob_len - 2)) + /* new format carries keyhandle but old format doesn't */ + if (!options->keyhandle) + return -EINVAL; + + /* must be big enough for at least the two be16 size counts */ + if (payload->blob_len < 4) + return -EINVAL; + + private_len = get_unaligned_be16(blob); + + /* must be big enough for following public_len */ + if (private_len + 2 + 2 > (payload->blob_len)) return -E2BIG; - public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]); + public_len = get_unaligned_be16(blob + 2 + private_len); + if (private_len + 2 + public_len + 2 > payload->blob_len) + return -E2BIG; + + pub = blob + 2 + private_len + 2; + /* key attributes are always at offset 4 */ + attrs = get_unaligned_be32(pub + 4); + + if ((attrs & (TPM2_OA_FIXED_TPM | TPM2_OA_FIXED_PARENT)) == + (TPM2_OA_FIXED_TPM | TPM2_OA_FIXED_PARENT)) + payload->migratable = 0; + else + payload->migratable = 1; + blob_len = private_len + public_len + 4; if (blob_len > payload->blob_len) return -E2BIG; @@ -204,19 +420,21 @@ static int tpm2_load_cmd(struct tpm_chip *chip, options->keyauth /* hmac */, TPM_DIGEST_SIZE); - tpm_buf_append(&buf, payload->blob, blob_len); + tpm_buf_append(&buf, blob, blob_len); if (buf.flags & TPM_BUF_OVERFLOW) { rc = -E2BIG; goto out; } - rc = tpm_send(chip, buf.data, tpm_buf_length(&buf)); + rc = tpm_transmit_cmd(chip, &buf, 4, "loading blob"); if (!rc) *blob_handle = be32_to_cpup( (__be32 *) &buf.data[TPM_HEADER_SIZE]); out: + if (blob != payload->blob) + kfree(blob); tpm_buf_destroy(&buf); if (rc > 0) @@ -258,16 +476,16 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, NULL /* nonce */, 0, TPM2_SA_CONTINUE_SESSION, options->blobauth /* hmac */, - TPM_DIGEST_SIZE); + options->blobauth_len); - rc = tpm_send(chip, buf.data, tpm_buf_length(&buf)); + rc = tpm_transmit_cmd(chip, &buf, 6, "unsealing"); if (rc > 0) rc = -EPERM; if (!rc) { data_len = be16_to_cpup( (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]); - if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE + 1) { + if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE) { rc = -EFAULT; goto out; } @@ -278,9 +496,19 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, } data = &buf.data[TPM_HEADER_SIZE + 6]; - memcpy(payload->key, data, data_len - 1); - payload->key_len = data_len - 1; - payload->migratable = data[data_len - 1]; + if (payload->old_format) { + /* migratable flag is at the end of the key */ + memcpy(payload->key, data, data_len - 1); + payload->key_len = data_len - 1; + payload->migratable = data[data_len - 1]; + } else { + /* + * migratable flag already collected from key + * attributes + */ + memcpy(payload->key, data, data_len); + payload->key_len = data_len; + } } out: @@ -304,12 +532,19 @@ int tpm2_unseal_trusted(struct tpm_chip *chip, u32 blob_handle; int rc; - rc = tpm2_load_cmd(chip, payload, options, &blob_handle); + rc = tpm_try_get_ops(chip); if (rc) return rc; + rc = tpm2_load_cmd(chip, payload, options, &blob_handle); + if (rc) + goto out; + rc = tpm2_unseal_cmd(chip, payload, options, blob_handle); tpm2_flush_context(chip, blob_handle); +out: + tpm_put_ops(chip); + return rc; } diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c index 6f12de4ce549..749e2a4dcb13 100644 --- a/security/keys/user_defined.c +++ b/security/keys/user_defined.c @@ -82,7 +82,7 @@ EXPORT_SYMBOL_GPL(user_preparse); */ void user_free_preparse(struct key_preparsed_payload *prep) { - kzfree(prep->payload.data[0]); + kfree_sensitive(prep->payload.data[0]); } EXPORT_SYMBOL_GPL(user_free_preparse); @@ -91,7 +91,7 @@ static void user_free_payload_rcu(struct rcu_head *head) struct user_key_payload *payload; payload = container_of(head, struct user_key_payload, rcu); - kzfree(payload); + kfree_sensitive(payload); } /* @@ -147,7 +147,7 @@ void user_destroy(struct key *key) { struct user_key_payload *upayload = key->payload.data[0]; - kzfree(upayload); + kfree_sensitive(upayload); } EXPORT_SYMBOL_GPL(user_destroy); @@ -168,7 +168,7 @@ EXPORT_SYMBOL_GPL(user_describe); * read the key data * - the key's semaphore is read-locked */ -long user_read(const struct key *key, char __user *buffer, size_t buflen) +long user_read(const struct key *key, char *buffer, size_t buflen) { const struct user_key_payload *upayload; long ret; @@ -181,8 +181,7 @@ long user_read(const struct key *key, char __user *buffer, size_t buflen) if (buflen > upayload->datalen) buflen = upayload->datalen; - if (copy_to_user(buffer, upayload->data, buflen) != 0) - ret = -EFAULT; + memcpy(buffer, upayload->data, buflen); } return ret; |