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Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Browse Source 
Pull security subsystem updates from James Morris:
 "Highlights:

   - A new LSM, "LoadPin", from Kees Cook is added, which allows forcing
     of modules and firmware to be loaded from a specific device (this
     is from ChromeOS, where the device as a whole is verified
     cryptographically via dm-verity).

     This is disabled by default but can be configured to be enabled by
     default (don't do this if you don't know what you're doing).

   - Keys: allow authentication data to be stored in an asymmetric key.
     Lots of general fixes and updates.

   - SELinux: add restrictions for loading of kernel modules via
     finit_module().  Distinguish non-init user namespace capability
     checks.  Apply execstack check on thread stacks"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (48 commits)
  LSM: LoadPin: provide enablement CONFIG
  Yama: use atomic allocations when reporting
  seccomp: Fix comment typo
  ima: add support for creating files using the mknodat syscall
  ima: fix ima_inode_post_setattr
  vfs: forbid write access when reading a file into memory
  fs: fix over-zealous use of "const"
  selinux: apply execstack check on thread stacks
  selinux: distinguish non-init user namespace capability checks
  LSM: LoadPin for kernel file loading restrictions
  fs: define a string representation of the kernel_read_file_id enumeration
  Yama: consolidate error reporting
  string_helpers: add kstrdup_quotable_file
  string_helpers: add kstrdup_quotable_cmdline
  string_helpers: add kstrdup_quotable
  selinux: check ss_initialized before revalidating an inode label
  selinux: delay inode label lookup as long as possible
  selinux: don't revalidate an inode's label when explicitly setting it
  selinux: Change bool variable name to index.
  KEYS: Add KEYCTL_DH_COMPUTE command
  ...
This commit is contained in:
Linus Torvalds
2016-05-19 09:21:36 -07:00
parent 2600a46ee0 b937190c40
commit f4f27d0028
82 changed files with 1915 additions and 807 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
crypto/asymmetric_keys/Kconfig
View File

@@ -1,5 +1,5 @@
menuconfig ASYMMETRIC_KEY_TYPE
tristate "Asymmetric (public-key cryptographic) key type"
bool "Asymmetric (public-key cryptographic) key type"
depends on KEYS
help
This option provides support for a key type that holds the data for
@@ -40,8 +40,7 @@ config PKCS7_MESSAGE_PARSER
config PKCS7_TEST_KEY
tristate "PKCS#7 testing key type"
depends on PKCS7_MESSAGE_PARSER
select SYSTEM_TRUSTED_KEYRING
depends on SYSTEM_DATA_VERIFICATION
help
This option provides a type of key that can be loaded up from a
PKCS#7 message - provided the message is signed by a trusted key. If
@@ -54,6 +53,7 @@ config PKCS7_TEST_KEY
config SIGNED_PE_FILE_VERIFICATION
bool "Support for PE file signature verification"
depends on PKCS7_MESSAGE_PARSER=y
depends on SYSTEM_DATA_VERIFICATION
select ASN1
select OID_REGISTRY
help

5
crypto/asymmetric_keys/Makefile
View File

@@ -4,7 +4,10 @@
obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o
asymmetric_keys-y := asymmetric_type.o signature.o
asymmetric_keys-y := \
asymmetric_type.o \
restrict.o \
signature.o
obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o

2
crypto/asymmetric_keys/asymmetric_keys.h
View File

@@ -9,6 +9,8 @@
* 2 of the Licence, or (at your option) any later version.
*/
#include <keys/asymmetric-type.h>
extern struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id);
extern int __asymmetric_key_hex_to_key_id(const char *id,

96
crypto/asymmetric_keys/asymmetric_type.c
View File

@@ -34,6 +34,95 @@ EXPORT_SYMBOL_GPL(key_being_used_for);
static LIST_HEAD(asymmetric_key_parsers);
static DECLARE_RWSEM(asymmetric_key_parsers_sem);
/**
* find_asymmetric_key - Find a key by ID.
* @keyring: The keys to search.
* @id_0: The first ID to look for or NULL.
* @id_1: The second ID to look for or NULL.
* @partial: Use partial match if true, exact if false.
*
* Find a key in the given keyring by identifier. The preferred identifier is
* the id_0 and the fallback identifier is the id_1. If both are given, the
* lookup is by the former, but the latter must also match.
*/
struct key *find_asymmetric_key(struct key *keyring,
const struct asymmetric_key_id *id_0,
const struct asymmetric_key_id *id_1,
bool partial)
{
struct key *key;
key_ref_t ref;
const char *lookup;
char *req, *p;
int len;
if (id_0) {
lookup = id_0->data;
len = id_0->len;
} else {
lookup = id_1->data;
len = id_1->len;
}
/* Construct an identifier "id:<keyid>". */
p = req = kmalloc(2 + 1 + len * 2 + 1, GFP_KERNEL);
if (!req)
return ERR_PTR(-ENOMEM);
if (partial) {
*p++ = 'i';
*p++ = 'd';
} else {
*p++ = 'e';
*p++ = 'x';
}
*p++ = ':';
p = bin2hex(p, lookup, len);
*p = 0;
pr_debug("Look up: \"%s\"\n", req);
ref = keyring_search(make_key_ref(keyring, 1),
&key_type_asymmetric, req);
if (IS_ERR(ref))
pr_debug("Request for key '%s' err %ld\n", req, PTR_ERR(ref));
kfree(req);
if (IS_ERR(ref)) {
switch (PTR_ERR(ref)) {
/* Hide some search errors */
case -EACCES:
case -ENOTDIR:
case -EAGAIN:
return ERR_PTR(-ENOKEY);
default:
return ERR_CAST(ref);
}
}
key = key_ref_to_ptr(ref);
if (id_0 && id_1) {
const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
if (!kids->id[0]) {
pr_debug("First ID matches, but second is missing\n");
goto reject;
}
if (!asymmetric_key_id_same(id_1, kids->id[1])) {
pr_debug("First ID matches, but second does not\n");
goto reject;
}
}
pr_devel("<==%s() = 0 [%x]\n", __func__, key_serial(key));
return key;
reject:
key_put(key);
return ERR_PTR(-EKEYREJECTED);
}
EXPORT_SYMBOL_GPL(find_asymmetric_key);
/**
* asymmetric_key_generate_id: Construct an asymmetric key ID
* @val_1: First binary blob
@@ -331,7 +420,8 @@ static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep)
pr_devel("==>%s()\n", __func__);
if (subtype) {
subtype->destroy(prep->payload.data[asym_crypto]);
subtype->destroy(prep->payload.data[asym_crypto],
prep->payload.data[asym_auth]);
module_put(subtype->owner);
}
asymmetric_key_free_kids(kids);
@@ -346,13 +436,15 @@ static void asymmetric_key_destroy(struct key *key)
struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
struct asymmetric_key_ids *kids = key->payload.data[asym_key_ids];
void *data = key->payload.data[asym_crypto];
void *auth = key->payload.data[asym_auth];
key->payload.data[asym_crypto] = NULL;
key->payload.data[asym_subtype] = NULL;
key->payload.data[asym_key_ids] = NULL;
key->payload.data[asym_auth] = NULL;
if (subtype) {
subtype->destroy(data);
subtype->destroy(data, auth);
module_put(subtype->owner);
}

21
crypto/asymmetric_keys/mscode_parser.c
View File

@@ -21,19 +21,13 @@
/*
* Parse a Microsoft Individual Code Signing blob
*/
int mscode_parse(struct pefile_context *ctx)
int mscode_parse(void *_ctx, const void *content_data, size_t data_len,
size_t asn1hdrlen)
{
const void *content_data;
size_t data_len;
int ret;
ret = pkcs7_get_content_data(ctx->pkcs7, &content_data, &data_len, 1);
if (ret) {
pr_debug("PKCS#7 message does not contain data\n");
return ret;
}
struct pefile_context *ctx = _ctx;
content_data -= asn1hdrlen;
data_len += asn1hdrlen;
pr_devel("Data: %zu [%*ph]\n", data_len, (unsigned)(data_len),
content_data);
@@ -129,7 +123,6 @@ int mscode_note_digest(void *context, size_t hdrlen,
{
struct pefile_context *ctx = context;
ctx->digest = value;
ctx->digest_len = vlen;
return 0;
ctx->digest = kmemdup(value, vlen, GFP_KERNEL);
return ctx->digest ? 0 : -ENOMEM;
}

72
crypto/asymmetric_keys/pkcs7_key_type.c
View File

@@ -13,12 +13,9 @@
#include <linux/key.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/verification.h>
#include <linux/key-type.h>
#include <keys/asymmetric-type.h>
#include <crypto/pkcs7.h>
#include <keys/user-type.h>
#include <keys/system_keyring.h>
#include "pkcs7_parser.h"
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("PKCS#7 testing key type");
@@ -28,58 +25,45 @@ module_param_named(usage, pkcs7_usage, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(pkcs7_usage,
"Usage to specify when verifying the PKCS#7 message");
/*
* Retrieve the PKCS#7 message content.
*/
static int pkcs7_view_content(void *ctx, const void *data, size_t len,
size_t asn1hdrlen)
{
struct key_preparsed_payload *prep = ctx;
const void *saved_prep_data;
size_t saved_prep_datalen;
int ret;
saved_prep_data = prep->data;
saved_prep_datalen = prep->datalen;
prep->data = data;
prep->datalen = len;
ret = user_preparse(prep);
prep->data = saved_prep_data;
prep->datalen = saved_prep_datalen;
return ret;
}
/*
* Preparse a PKCS#7 wrapped and validated data blob.
*/
static int pkcs7_preparse(struct key_preparsed_payload *prep)
{
enum key_being_used_for usage = pkcs7_usage;
struct pkcs7_message *pkcs7;
const void *data, *saved_prep_data;
size_t datalen, saved_prep_datalen;
bool trusted;
int ret;
kenter("");
if (usage >= NR__KEY_BEING_USED_FOR) {
pr_err("Invalid usage type %d\n", usage);
return -EINVAL;
}
saved_prep_data = prep->data;
saved_prep_datalen = prep->datalen;
pkcs7 = pkcs7_parse_message(saved_prep_data, saved_prep_datalen);
if (IS_ERR(pkcs7)) {
ret = PTR_ERR(pkcs7);
goto error;
}
ret = pkcs7_verify(pkcs7, usage);
if (ret < 0)
goto error_free;
ret = pkcs7_validate_trust(pkcs7, system_trusted_keyring, &trusted);
if (ret < 0)
goto error_free;
if (!trusted)
pr_warn("PKCS#7 message doesn't chain back to a trusted key\n");
ret = pkcs7_get_content_data(pkcs7, &data, &datalen, false);
if (ret < 0)
goto error_free;
prep->data = data;
prep->datalen = datalen;
ret = user_preparse(prep);
prep->data = saved_prep_data;
prep->datalen = saved_prep_datalen;
error_free:
pkcs7_free_message(pkcs7);
error:
kleave(" = %d", ret);
return ret;
return verify_pkcs7_signature(NULL, 0,
prep->data, prep->datalen,
NULL, usage,
pkcs7_view_content, prep);
}
/*

58
crypto/asymmetric_keys/pkcs7_parser.c
View File

@@ -44,9 +44,7 @@ struct pkcs7_parse_context {
static void pkcs7_free_signed_info(struct pkcs7_signed_info *sinfo)
{
if (sinfo) {
kfree(sinfo->sig.s);
kfree(sinfo->sig.digest);
kfree(sinfo->signing_cert_id);
public_key_signature_free(sinfo->sig);
kfree(sinfo);
}
}
@@ -125,6 +123,10 @@ struct pkcs7_message *pkcs7_parse_message(const void *data, size_t datalen)
ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
if (!ctx->sinfo)
goto out_no_sinfo;
ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
GFP_KERNEL);
if (!ctx->sinfo->sig)
goto out_no_sig;
ctx->data = (unsigned long)data;
ctx->ppcerts = &ctx->certs;
@@ -150,6 +152,7 @@ out:
ctx->certs = cert->next;
x509_free_certificate(cert);
}
out_no_sig:
pkcs7_free_signed_info(ctx->sinfo);
out_no_sinfo:
pkcs7_free_message(ctx->msg);
@@ -165,24 +168,25 @@ EXPORT_SYMBOL_GPL(pkcs7_parse_message);
* @pkcs7: The preparsed PKCS#7 message to access
* @_data: Place to return a pointer to the data
* @_data_len: Place to return the data length
* @want_wrapper: True if the ASN.1 object header should be included in the data
* @_headerlen: Size of ASN.1 header not included in _data
*
* Get access to the data content of the PKCS#7 message, including, optionally,
* the header of the ASN.1 object that contains it. Returns -ENODATA if the
* data object was missing from the message.
* Get access to the data content of the PKCS#7 message. The size of the
* header of the ASN.1 object that contains it is also provided and can be used
* to adjust *_data and *_data_len to get the entire object.
*
* Returns -ENODATA if the data object was missing from the message.
*/
int pkcs7_get_content_data(const struct pkcs7_message *pkcs7,
const void **_data, size_t *_data_len,
bool want_wrapper)
size_t *_headerlen)
{
size_t wrapper;
if (!pkcs7->data)
return -ENODATA;
wrapper = want_wrapper ? pkcs7->data_hdrlen : 0;
*_data = pkcs7->data - wrapper;
*_data_len = pkcs7->data_len + wrapper;
*_data = pkcs7->data;
*_data_len = pkcs7->data_len;
if (_headerlen)
*_headerlen = pkcs7->data_hdrlen;
return 0;
}
EXPORT_SYMBOL_GPL(pkcs7_get_content_data);
@@ -218,25 +222,25 @@ int pkcs7_sig_note_digest_algo(void *context, size_t hdrlen,
switch (ctx->last_oid) {
case OID_md4:
ctx->sinfo->sig.hash_algo = "md4";
ctx->sinfo->sig->hash_algo = "md4";
break;
case OID_md5:
ctx->sinfo->sig.hash_algo = "md5";
ctx->sinfo->sig->hash_algo = "md5";
break;
case OID_sha1:
ctx->sinfo->sig.hash_algo = "sha1";
ctx->sinfo->sig->hash_algo = "sha1";
break;
case OID_sha256:
ctx->sinfo->sig.hash_algo = "sha256";
ctx->sinfo->sig->hash_algo = "sha256";
break;
case OID_sha384:
ctx->sinfo->sig.hash_algo = "sha384";
ctx->sinfo->sig->hash_algo = "sha384";
break;
case OID_sha512:
ctx->sinfo->sig.hash_algo = "sha512";
ctx->sinfo->sig->hash_algo = "sha512";
break;
case OID_sha224:
ctx->sinfo->sig.hash_algo = "sha224";
ctx->sinfo->sig->hash_algo = "sha224";
break;
default:
printk("Unsupported digest algo: %u\n", ctx->last_oid);
@@ -256,7 +260,7 @@ int pkcs7_sig_note_pkey_algo(void *context, size_t hdrlen,
switch (ctx->last_oid) {
case OID_rsaEncryption:
ctx->sinfo->sig.pkey_algo = "rsa";
ctx->sinfo->sig->pkey_algo = "rsa";
break;
default:
printk("Unsupported pkey algo: %u\n", ctx->last_oid);
@@ -616,11 +620,11 @@ int pkcs7_sig_note_signature(void *context, size_t hdrlen,
{
struct pkcs7_parse_context *ctx = context;
ctx->sinfo->sig.s = kmemdup(value, vlen, GFP_KERNEL);
if (!ctx->sinfo->sig.s)
ctx->sinfo->sig->s = kmemdup(value, vlen, GFP_KERNEL);
if (!ctx->sinfo->sig->s)
return -ENOMEM;
ctx->sinfo->sig.s_size = vlen;
ctx->sinfo->sig->s_size = vlen;
return 0;
}
@@ -656,12 +660,16 @@ int pkcs7_note_signed_info(void *context, size_t hdrlen,
pr_devel("SINFO KID: %u [%*phN]\n", kid->len, kid->len, kid->data);
sinfo->signing_cert_id = kid;
sinfo->sig->auth_ids[0] = kid;
sinfo->index = ++ctx->sinfo_index;
*ctx->ppsinfo = sinfo;
ctx->ppsinfo = &sinfo->next;
ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
if (!ctx->sinfo)
return -ENOMEM;
ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
GFP_KERNEL);
if (!ctx->sinfo->sig)
return -ENOMEM;
return 0;
}

11
crypto/asymmetric_keys/pkcs7_parser.h
View File

@@ -22,7 +22,6 @@ struct pkcs7_signed_info {
struct pkcs7_signed_info *next;
struct x509_certificate *signer; /* Signing certificate (in msg->certs) */
unsigned index;
bool trusted;
bool unsupported_crypto; /* T if not usable due to missing crypto */
/* Message digest - the digest of the Content Data (or NULL) */
@@ -41,19 +40,17 @@ struct pkcs7_signed_info {
#define sinfo_has_ms_statement_type 5
time64_t signing_time;
/* Issuing cert serial number and issuer's name [PKCS#7 or CMS ver 1]
* or issuing cert's SKID [CMS ver 3].
*/
struct asymmetric_key_id *signing_cert_id;
/* Message signature.
*
* This contains the generated digest of _either_ the Content Data or
* the Authenticated Attributes [RFC2315 9.3]. If the latter, one of
* the attributes contains the digest of the the Content Data within
* it.
*
* THis also contains the issuing cert serial number and issuer's name
* [PKCS#7 or CMS ver 1] or issuing cert's SKID [CMS ver 3].
*/
struct public_key_signature sig;
struct public_key_signature *sig;
};
struct pkcs7_message {

43
crypto/asymmetric_keys/pkcs7_trust.c
View File

@@ -27,10 +27,9 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
struct pkcs7_signed_info *sinfo,
struct key *trust_keyring)
{
struct public_key_signature *sig = &sinfo->sig;
struct public_key_signature *sig = sinfo->sig;
struct x509_certificate *x509, *last = NULL, *p;
struct key *key;
bool trusted;
int ret;
kenter(",%u,", sinfo->index);
@@ -42,10 +41,8 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
for (x509 = sinfo->signer; x509; x509 = x509->signer) {
if (x509->seen) {
if (x509->verified) {
trusted = x509->trusted;
if (x509->verified)
goto verified;
}
kleave(" = -ENOKEY [cached]");
return -ENOKEY;
}
@@ -54,9 +51,8 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
/* Look to see if this certificate is present in the trusted
* keys.
*/
key = x509_request_asymmetric_key(trust_keyring,
x509->id, x509->skid,
false);
key = find_asymmetric_key(trust_keyring,
x509->id, x509->skid, false);
if (!IS_ERR(key)) {
/* One of the X.509 certificates in the PKCS#7 message
* is apparently the same as one we already trust.
@@ -80,17 +76,17 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
might_sleep();
last = x509;
sig = &last->sig;
sig = last->sig;
}
/* No match - see if the root certificate has a signer amongst the
* trusted keys.
*/
if (last && (last->akid_id || last->akid_skid)) {
key = x509_request_asymmetric_key(trust_keyring,
last->akid_id,
last->akid_skid,
false);
if (last && (last->sig->auth_ids[0] || last->sig->auth_ids[1])) {
key = find_asymmetric_key(trust_keyring,
last->sig->auth_ids[0],
last->sig->auth_ids[1],
false);
if (!IS_ERR(key)) {
x509 = last;
pr_devel("sinfo %u: Root cert %u signer is key %x\n",
@@ -104,10 +100,8 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
/* As a last resort, see if we have a trusted public key that matches
* the signed info directly.
*/
key = x509_request_asymmetric_key(trust_keyring,
sinfo->signing_cert_id,
NULL,
false);
key = find_asymmetric_key(trust_keyring,
sinfo->sig->auth_ids[0], NULL, false);
if (!IS_ERR(key)) {
pr_devel("sinfo %u: Direct signer is key %x\n",
sinfo->index, key_serial(key));
@@ -122,7 +116,6 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
matched:
ret = verify_signature(key, sig);
trusted = test_bit(KEY_FLAG_TRUSTED, &key->flags);
key_put(key);
if (ret < 0) {
if (ret == -ENOMEM)
@@ -134,12 +127,9 @@ matched:
verified:
if (x509) {
x509->verified = true;
for (p = sinfo->signer; p != x509; p = p->signer) {
for (p = sinfo->signer; p != x509; p = p->signer)
p->verified = true;
p->trusted = trusted;
}
}
sinfo->trusted = trusted;
kleave(" = 0");
return 0;
}
@@ -148,7 +138,6 @@ verified:
* pkcs7_validate_trust - Validate PKCS#7 trust chain
* @pkcs7: The PKCS#7 certificate to validate
* @trust_keyring: Signing certificates to use as starting points
* @_trusted: Set to true if trustworth, false otherwise
*
* Validate that the certificate chain inside the PKCS#7 message intersects
* keys we already know and trust.
@@ -170,16 +159,13 @@ verified:
* May also return -ENOMEM.
*/
int pkcs7_validate_trust(struct pkcs7_message *pkcs7,
struct key *trust_keyring,
bool *_trusted)
struct key *trust_keyring)
{
struct pkcs7_signed_info *sinfo;
struct x509_certificate *p;
int cached_ret = -ENOKEY;
int ret;
*_trusted = false;
for (p = pkcs7->certs; p; p = p->next)
p->seen = false;
@@ -193,7 +179,6 @@ int pkcs7_validate_trust(struct pkcs7_message *pkcs7,
cached_ret = -ENOPKG;
continue;
case 0:
*_trusted |= sinfo->trusted;
cached_ret = 0;
continue;
default:

107
crypto/asymmetric_keys/pkcs7_verify.c
View File

@@ -25,34 +25,36 @@
static int pkcs7_digest(struct pkcs7_message *pkcs7,
struct pkcs7_signed_info *sinfo)
{
struct public_key_signature *sig = sinfo->sig;
struct crypto_shash *tfm;
struct shash_desc *desc;
size_t digest_size, desc_size;
void *digest;
size_t desc_size;
int ret;
kenter(",%u,%s", sinfo->index, sinfo->sig.hash_algo);
kenter(",%u,%s", sinfo->index, sinfo->sig->hash_algo);
if (!sinfo->sig.hash_algo)
if (!sinfo->sig->hash_algo)
return -ENOPKG;
/* Allocate the hashing algorithm we're going to need and find out how
* big the hash operational data will be.
*/
tfm = crypto_alloc_shash(sinfo->sig.hash_algo, 0, 0);
tfm = crypto_alloc_shash(sinfo->sig->hash_algo, 0, 0);
if (IS_ERR(tfm))
return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm);
desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
sinfo->sig.digest_size = digest_size = crypto_shash_digestsize(tfm);
sig->digest_size = crypto_shash_digestsize(tfm);
ret = -ENOMEM;
digest = kzalloc(ALIGN(digest_size, __alignof__(*desc)) + desc_size,
GFP_KERNEL);
if (!digest)
sig->digest = kmalloc(sig->digest_size, GFP_KERNEL);
if (!sig->digest)
goto error_no_desc;
desc = kzalloc(desc_size, GFP_KERNEL);
if (!desc)
goto error_no_desc;
desc = PTR_ALIGN(digest + digest_size, __alignof__(*desc));
desc->tfm = tfm;
desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
@@ -60,10 +62,11 @@ static int pkcs7_digest(struct pkcs7_message *pkcs7,
ret = crypto_shash_init(desc);
if (ret < 0)
goto error;
ret = crypto_shash_finup(desc, pkcs7->data, pkcs7->data_len, digest);
ret = crypto_shash_finup(desc, pkcs7->data, pkcs7->data_len,
sig->digest);
if (ret < 0)
goto error;
pr_devel("MsgDigest = [%*ph]\n", 8, digest);
pr_devel("MsgDigest = [%*ph]\n", 8, sig->digest);
/* However, if there are authenticated attributes, there must be a
* message digest attribute amongst them which corresponds to the
@@ -78,14 +81,15 @@ static int pkcs7_digest(struct pkcs7_message *pkcs7,
goto error;
}
if (sinfo->msgdigest_len != sinfo->sig.digest_size) {
if (sinfo->msgdigest_len != sig->digest_size) {
pr_debug("Sig %u: Invalid digest size (%u)\n",
sinfo->index, sinfo->msgdigest_len);
ret = -EBADMSG;
goto error;
}
if (memcmp(digest, sinfo->msgdigest, sinfo->msgdigest_len) != 0) {
if (memcmp(sig->digest, sinfo->msgdigest,
sinfo->msgdigest_len) != 0) {
pr_debug("Sig %u: Message digest doesn't match\n",
sinfo->index);
ret = -EKEYREJECTED;
@@ -97,7 +101,7 @@ static int pkcs7_digest(struct pkcs7_message *pkcs7,
* convert the attributes from a CONT.0 into a SET before we
* hash it.
*/
memset(digest, 0, sinfo->sig.digest_size);
memset(sig->digest, 0, sig->digest_size);
ret = crypto_shash_init(desc);
if (ret < 0)
@@ -107,17 +111,14 @@ static int pkcs7_digest(struct pkcs7_message *pkcs7,
if (ret < 0)
goto error;
ret = crypto_shash_finup(desc, sinfo->authattrs,
sinfo->authattrs_len, digest);
sinfo->authattrs_len, sig->digest);
if (ret < 0)
goto error;
pr_devel("AADigest = [%*ph]\n", 8, digest);
pr_devel("AADigest = [%*ph]\n", 8, sig->digest);
}
sinfo->sig.digest = digest;
digest = NULL;
error:
kfree(digest);
kfree(desc);
error_no_desc:
crypto_free_shash(tfm);
kleave(" = %d", ret);
@@ -144,12 +145,12 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7,
* PKCS#7 message - but I can't be 100% sure of that. It's
* possible this will need element-by-element comparison.
*/
if (!asymmetric_key_id_same(x509->id, sinfo->signing_cert_id))
if (!asymmetric_key_id_same(x509->id, sinfo->sig->auth_ids[0]))
continue;
pr_devel("Sig %u: Found cert serial match X.509[%u]\n",
sinfo->index, certix);
if (x509->pub->pkey_algo != sinfo->sig.pkey_algo) {
if (x509->pub->pkey_algo != sinfo->sig->pkey_algo) {
pr_warn("Sig %u: X.509 algo and PKCS#7 sig algo don't match\n",
sinfo->index);
continue;
@@ -164,7 +165,7 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7,
*/
pr_debug("Sig %u: Issuing X.509 cert not found (#%*phN)\n",
sinfo->index,
sinfo->signing_cert_id->len, sinfo->signing_cert_id->data);
sinfo->sig->auth_ids[0]->len, sinfo->sig->auth_ids[0]->data);
return 0;
}
@@ -174,6 +175,7 @@ static int pkcs7_find_key(struct pkcs7_message *pkcs7,
static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
struct pkcs7_signed_info *sinfo)
{
struct public_key_signature *sig;
struct x509_certificate *x509 = sinfo->signer, *p;
struct asymmetric_key_id *auth;
int ret;
@@ -188,34 +190,26 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
x509->subject,
x509->raw_serial_size, x509->raw_serial);
x509->seen = true;
ret = x509_get_sig_params(x509);
if (ret < 0)
goto maybe_missing_crypto_in_x509;
if (x509->unsupported_key)
goto unsupported_crypto_in_x509;
pr_debug("- issuer %s\n", x509->issuer);
if (x509->akid_id)
sig = x509->sig;
if (sig->auth_ids[0])
pr_debug("- authkeyid.id %*phN\n",
x509->akid_id->len, x509->akid_id->data);
if (x509->akid_skid)
sig->auth_ids[0]->len, sig->auth_ids[0]->data);
if (sig->auth_ids[1])
pr_debug("- authkeyid.skid %*phN\n",
x509->akid_skid->len, x509->akid_skid->data);
sig->auth_ids[1]->len, sig->auth_ids[1]->data);
if ((!x509->akid_id && !x509->akid_skid) ||
strcmp(x509->subject, x509->issuer) == 0) {
if (x509->self_signed) {
/* If there's no authority certificate specified, then
* the certificate must be self-signed and is the root
* of the chain. Likewise if the cert is its own
* authority.
*/
pr_debug("- no auth?\n");
if (x509->raw_subject_size != x509->raw_issuer_size ||
memcmp(x509->raw_subject, x509->raw_issuer,
x509->raw_issuer_size) != 0)
return 0;
ret = x509_check_signature(x509->pub, x509);
if (ret < 0)
goto maybe_missing_crypto_in_x509;
if (x509->unsupported_sig)
goto unsupported_crypto_in_x509;
x509->signer = x509;
pr_debug("- self-signed\n");
return 0;
@@ -224,7 +218,7 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
/* Look through the X.509 certificates in the PKCS#7 message's
* list to see if the next one is there.
*/
auth = x509->akid_id;
auth = sig->auth_ids[0];
if (auth) {
pr_debug("- want %*phN\n", auth->len, auth->data);
for (p = pkcs7->certs; p; p = p->next) {
@@ -234,7 +228,7 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
goto found_issuer_check_skid;
}
} else {
auth = x509->akid_skid;
auth = sig->auth_ids[1];
pr_debug("- want %*phN\n", auth->len, auth->data);
for (p = pkcs7->certs; p; p = p->next) {
if (!p->skid)
@@ -254,8 +248,8 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
/* We matched issuer + serialNumber, but if there's an
* authKeyId.keyId, that must match the CA subjKeyId also.
*/
if (x509->akid_skid &&
!asymmetric_key_id_same(p->skid, x509->akid_skid)) {
if (sig->auth_ids[1] &&
!asymmetric_key_id_same(p->skid, sig->auth_ids[1])) {
pr_warn("Sig %u: X.509 chain contains auth-skid nonmatch (%u->%u)\n",
sinfo->index, x509->index, p->index);
return -EKEYREJECTED;
@@ -267,7 +261,7 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
sinfo->index);
return 0;
}
ret = x509_check_signature(p->pub, x509);
ret = public_key_verify_signature(p->pub, p->sig);
if (ret < 0)
return ret;
x509->signer = p;
@@ -279,16 +273,14 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
might_sleep();
}
maybe_missing_crypto_in_x509:
unsupported_crypto_in_x509:
/* Just prune the certificate chain at this point if we lack some
* crypto module to go further. Note, however, we don't want to set
* sinfo->missing_crypto as the signed info block may still be
* sinfo->unsupported_crypto as the signed info block may still be
* validatable against an X.509 cert lower in the chain that we have a
* trusted copy of.
*/
if (ret == -ENOPKG)
return 0;
return ret;
return 0;
}
/*
@@ -332,7 +324,7 @@ static int pkcs7_verify_one(struct pkcs7_message *pkcs7,
}
/* Verify the PKCS#7 binary against the key */
ret = public_key_verify_signature(sinfo->signer->pub, &sinfo->sig);
ret = public_key_verify_signature(sinfo->signer->pub, sinfo->sig);
if (ret < 0)
return ret;
@@ -375,9 +367,8 @@ int pkcs7_verify(struct pkcs7_message *pkcs7,
enum key_being_used_for usage)
{
struct pkcs7_signed_info *sinfo;
struct x509_certificate *x509;
int enopkg = -ENOPKG;
int ret, n;
int ret;
kenter("");
@@ -419,12 +410,6 @@ int pkcs7_verify(struct pkcs7_message *pkcs7,
return -EINVAL;
}
for (n = 0, x509 = pkcs7->certs; x509; x509 = x509->next, n++) {
ret = x509_get_sig_params(x509);
if (ret < 0)
return ret;
}
for (sinfo = pkcs7->signed_infos; sinfo; sinfo = sinfo->next) {
ret = pkcs7_verify_one(pkcs7, sinfo);
if (ret < 0) {

20
crypto/asymmetric_keys/public_key.c
View File

@@ -39,15 +39,23 @@ static void public_key_describe(const struct key *asymmetric_key,
/*
* Destroy a public key algorithm key.
*/
void public_key_destroy(void *payload)
void public_key_free(struct public_key *key)
{
struct public_key *key = payload;
if (key)
if (key) {
kfree(key->key);
kfree(key);
kfree(key);
}
}
EXPORT_SYMBOL_GPL(public_key_free);
/*
* Destroy a public key algorithm key.
*/
static void public_key_destroy(void *payload0, void *payload3)
{
public_key_free(payload0);
public_key_signature_free(payload3);
}
EXPORT_SYMBOL_GPL(public_key_destroy);
struct public_key_completion {
struct completion completion;

108
crypto/asymmetric_keys/restrict.c Normal file
View File

@@ -0,0 +1,108 @@
/* Instantiate a public key crypto key from an X.509 Certificate
*
* Copyright (C) 2012, 2016 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#define pr_fmt(fmt) "ASYM: "fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <crypto/public_key.h>
#include "asymmetric_keys.h"
static bool use_builtin_keys;
static struct asymmetric_key_id *ca_keyid;
#ifndef MODULE
static struct {
struct asymmetric_key_id id;
unsigned char data[10];
} cakey;
static int __init ca_keys_setup(char *str)
{
if (!str) /* default system keyring */
return 1;
if (strncmp(str, "id:", 3) == 0) {
struct asymmetric_key_id *p = &cakey.id;
size_t hexlen = (strlen(str) - 3) / 2;
int ret;
if (hexlen == 0 || hexlen > sizeof(cakey.data)) {
pr_err("Missing or invalid ca_keys id\n");
return 1;
}
ret = __asymmetric_key_hex_to_key_id(str + 3, p, hexlen);
if (ret < 0)
pr_err("Unparsable ca_keys id hex string\n");
else
ca_keyid = p; /* owner key 'id:xxxxxx' */
} else if (strcmp(str, "builtin") == 0) {
use_builtin_keys = true;
}
return 1;
}
__setup("ca_keys=", ca_keys_setup);
#endif
/**
* restrict_link_by_signature - Restrict additions to a ring of public keys
* @trust_keyring: A ring of keys that can be used to vouch for the new cert.
* @type: The type of key being added.
* @payload: The payload of the new key.
*
* Check the new certificate against the ones in the trust keyring. If one of
* those is the signing key and validates the new certificate, then mark the
* new certificate as being trusted.
*
* Returns 0 if the new certificate was accepted, -ENOKEY if we couldn't find a
* matching parent certificate in the trusted list, -EKEYREJECTED if the
* signature check fails or the key is blacklisted and some other error if
* there is a matching certificate but the signature check cannot be performed.
*/
int restrict_link_by_signature(struct key *trust_keyring,
const struct key_type *type,
const union key_payload *payload)
{
const struct public_key_signature *sig;
struct key *key;
int ret;
pr_devel("==>%s()\n", __func__);
if (!trust_keyring)
return -ENOKEY;
if (type != &key_type_asymmetric)
return -EOPNOTSUPP;
sig = payload->data[asym_auth];
if (!sig->auth_ids[0] && !sig->auth_ids[1])
return 0;
if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid))
return -EPERM;
/* See if we have a key that signed this one. */
key = find_asymmetric_key(trust_keyring,
sig->auth_ids[0], sig->auth_ids[1],
false);
if (IS_ERR(key))
return -ENOKEY;
if (use_builtin_keys && !test_bit(KEY_FLAG_BUILTIN, &key->flags))
ret = -ENOKEY;
else
ret = verify_signature(key, sig);
key_put(key);
return ret;
}

18
crypto/asymmetric_keys/signature.c
View File

@@ -15,9 +15,27 @@
#include <keys/asymmetric-subtype.h>
#include <linux/export.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <crypto/public_key.h>
#include "asymmetric_keys.h"
/*
* Destroy a public key signature.
*/
void public_key_signature_free(struct public_key_signature *sig)
{
int i;
if (sig) {
for (i = 0; i < ARRAY_SIZE(sig->auth_ids); i++)
kfree(sig->auth_ids[i]);
kfree(sig->s);
kfree(sig->digest);
kfree(sig);
}
}
EXPORT_SYMBOL_GPL(public_key_signature_free);
/**
* verify_signature - Initiate the use of an asymmetric key to verify a signature
* @key: The asymmetric key to verify against

40
crypto/asymmetric_keys/verify_pefile.c
View File

@@ -16,7 +16,7 @@
#include <linux/err.h>
#include <linux/pe.h>
#include <linux/asn1.h>
#include <crypto/pkcs7.h>
#include <linux/verification.h>
#include <crypto/hash.h>
#include "verify_pefile.h"
@@ -392,9 +392,8 @@ error_no_desc:
* verify_pefile_signature - Verify the signature on a PE binary image
* @pebuf: Buffer containing the PE binary image
* @pelen: Length of the binary image
* @trust_keyring: Signing certificates to use as starting points
* @trust_keys: Signing certificate(s) to use as starting points
* @usage: The use to which the key is being put.
* @_trusted: Set to true if trustworth, false otherwise
*
* Validate that the certificate chain inside the PKCS#7 message inside the PE
* binary image intersects keys we already know and trust.
@@ -418,14 +417,10 @@ error_no_desc:
* May also return -ENOMEM.
*/
int verify_pefile_signature(const void *pebuf, unsigned pelen,
struct key *trusted_keyring,
enum key_being_used_for usage,
bool *_trusted)
struct key *trusted_keys,
enum key_being_used_for usage)
{
struct pkcs7_message *pkcs7;
struct pefile_context ctx;
const void *data;
size_t datalen;
int ret;
kenter("");
@@ -439,19 +434,10 @@ int verify_pefile_signature(const void *pebuf, unsigned pelen,
if (ret < 0)
return ret;
pkcs7 = pkcs7_parse_message(pebuf + ctx.sig_offset, ctx.sig_len);
if (IS_ERR(pkcs7))
return PTR_ERR(pkcs7);
ctx.pkcs7 = pkcs7;
ret = pkcs7_get_content_data(ctx.pkcs7, &data, &datalen, false);
if (ret < 0 || datalen == 0) {
pr_devel("PKCS#7 message does not contain data\n");
ret = -EBADMSG;
goto error;
}
ret = mscode_parse(&ctx);
ret = verify_pkcs7_signature(NULL, 0,
pebuf + ctx.sig_offset, ctx.sig_len,
trusted_keys, usage,
mscode_parse, &ctx);
if (ret < 0)
goto error;
@@ -462,16 +448,8 @@ int verify_pefile_signature(const void *pebuf, unsigned pelen,
* contents.
*/
ret = pefile_digest_pe(pebuf, pelen, &ctx);
if (ret < 0)
goto error;
ret = pkcs7_verify(pkcs7, usage);
if (ret < 0)
goto error;
ret = pkcs7_validate_trust(pkcs7, trusted_keyring, _trusted);
error:
pkcs7_free_message(ctx.pkcs7);
kfree(ctx.digest);
return ret;
}

5
crypto/asymmetric_keys/verify_pefile.h
View File

@@ -9,7 +9,6 @@
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/verify_pefile.h>
#include <crypto/pkcs7.h>
#include <crypto/hash_info.h>
@@ -23,7 +22,6 @@ struct pefile_context {
unsigned sig_offset;
unsigned sig_len;
const struct section_header *secs;
struct pkcs7_message *pkcs7;
/* PKCS#7 MS Individual Code Signing content */
const void *digest; /* Digest */
@@ -39,4 +37,5 @@ struct pefile_context {
/*
* mscode_parser.c
*/
extern int mscode_parse(struct pefile_context *ctx);
extern int mscode_parse(void *_ctx, const void *content_data, size_t data_len,
size_t asn1hdrlen);

52
crypto/asymmetric_keys/x509_cert_parser.c
View File

@@ -47,15 +47,12 @@ struct x509_parse_context {
void x509_free_certificate(struct x509_certificate *cert)
{
if (cert) {
public_key_destroy(cert->pub);
public_key_free(cert->pub);
public_key_signature_free(cert->sig);
kfree(cert->issuer);
kfree(cert->subject);
kfree(cert->id);
kfree(cert->skid);
kfree(cert->akid_id);
kfree(cert->akid_skid);
kfree(cert->sig.digest);
kfree(cert->sig.s);
kfree(cert);
}
}
@@ -78,6 +75,9 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
cert->pub = kzalloc(sizeof(struct public_key), GFP_KERNEL);
if (!cert->pub)
goto error_no_ctx;
cert->sig = kzalloc(sizeof(struct public_key_signature), GFP_KERNEL);
if (!cert->sig)
goto error_no_ctx;
ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL);
if (!ctx)
goto error_no_ctx;
@@ -108,6 +108,11 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
cert->pub->keylen = ctx->key_size;
/* Grab the signature bits */
ret = x509_get_sig_params(cert);
if (ret < 0)
goto error_decode;
/* Generate cert issuer + serial number key ID */
kid = asymmetric_key_generate_id(cert->raw_serial,
cert->raw_serial_size,
@@ -119,6 +124,11 @@ struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
}
cert->id = kid;
/* Detect self-signed certificates */
ret = x509_check_for_self_signed(cert);
if (ret < 0)
goto error_decode;
kfree(ctx);
return cert;
@@ -188,33 +198,33 @@ int x509_note_pkey_algo(void *context, size_t hdrlen,
return -ENOPKG; /* Unsupported combination */
case OID_md4WithRSAEncryption:
ctx->cert->sig.hash_algo = "md4";
ctx->cert->sig.pkey_algo = "rsa";
ctx->cert->sig->hash_algo = "md4";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha1WithRSAEncryption:
ctx->cert->sig.hash_algo = "sha1";
ctx->cert->sig.pkey_algo = "rsa";
ctx->cert->sig->hash_algo = "sha1";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha256WithRSAEncryption:
ctx->cert->sig.hash_algo = "sha256";
ctx->cert->sig.pkey_algo = "rsa";
ctx->cert->sig->hash_algo = "sha256";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha384WithRSAEncryption:
ctx->cert->sig.hash_algo = "sha384";
ctx->cert->sig.pkey_algo = "rsa";
ctx->cert->sig->hash_algo = "sha384";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha512WithRSAEncryption:
ctx->cert->sig.hash_algo = "sha512";
ctx->cert->sig.pkey_algo = "rsa";
ctx->cert->sig->hash_algo = "sha512";
ctx->cert->sig->pkey_algo = "rsa";
break;
case OID_sha224WithRSAEncryption:
ctx->cert->sig.hash_algo = "sha224";
ctx->cert->sig.pkey_algo = "rsa";
ctx->cert->sig->hash_algo = "sha224";
ctx->cert->sig->pkey_algo = "rsa";
break;
}
@@ -572,14 +582,14 @@ int x509_akid_note_kid(void *context, size_t hdrlen,
pr_debug("AKID: keyid: %*phN\n", (int)vlen, value);
if (ctx->cert->akid_skid)
if (ctx->cert->sig->auth_ids[1])
return 0;
kid = asymmetric_key_generate_id(value, vlen, "", 0);
if (IS_ERR(kid))
return PTR_ERR(kid);
pr_debug("authkeyid %*phN\n", kid->len, kid->data);
ctx->cert->akid_skid = kid;
ctx->cert->sig->auth_ids[1] = kid;
return 0;
}
@@ -611,7 +621,7 @@ int x509_akid_note_serial(void *context, size_t hdrlen,
pr_debug("AKID: serial: %*phN\n", (int)vlen, value);
if (!ctx->akid_raw_issuer || ctx->cert->akid_id)
if (!ctx->akid_raw_issuer || ctx->cert->sig->auth_ids[0])
return 0;
kid = asymmetric_key_generate_id(value,
@@ -622,6 +632,6 @@ int x509_akid_note_serial(void *context, size_t hdrlen,
return PTR_ERR(kid);
pr_debug("authkeyid %*phN\n", kid->len, kid->data);
ctx->cert->akid_id = kid;
ctx->cert->sig->auth_ids[0] = kid;
return 0;
}

12
crypto/asymmetric_keys/x509_parser.h
View File

@@ -17,13 +17,11 @@ struct x509_certificate {
struct x509_certificate *next;
struct x509_certificate *signer; /* Certificate that signed this one */
struct public_key *pub; /* Public key details */
struct public_key_signature sig; /* Signature parameters */
struct public_key_signature *sig; /* Signature parameters */
char *issuer; /* Name of certificate issuer */
char *subject; /* Name of certificate subject */
struct asymmetric_key_id *id; /* Issuer + Serial number */
struct asymmetric_key_id *skid; /* Subject + subjectKeyId (optional) */
struct asymmetric_key_id *akid_id; /* CA AuthKeyId matching ->id (optional) */
struct asymmetric_key_id *akid_skid; /* CA AuthKeyId matching ->skid (optional) */
time64_t valid_from;
time64_t valid_to;
const void *tbs; /* Signed data */
@@ -41,8 +39,9 @@ struct x509_certificate {
unsigned index;
bool seen; /* Infinite recursion prevention */
bool verified;
bool trusted;
bool unsupported_crypto; /* T if can't be verified due to missing crypto */
bool self_signed; /* T if self-signed (check unsupported_sig too) */
bool unsupported_key; /* T if key uses unsupported crypto */
bool unsupported_sig; /* T if signature uses unsupported crypto */
};
/*
@@ -58,5 +57,4 @@ extern int x509_decode_time(time64_t *_t, size_t hdrlen,
* x509_public_key.c
*/
extern int x509_get_sig_params(struct x509_certificate *cert);
extern int x509_check_signature(const struct public_key *pub,
struct x509_certificate *cert);
extern int x509_check_for_self_signed(struct x509_certificate *cert);

297
crypto/asymmetric_keys/x509_public_key.c
View File

@@ -20,256 +20,133 @@
#include "asymmetric_keys.h"
#include "x509_parser.h"
static bool use_builtin_keys;
static struct asymmetric_key_id *ca_keyid;
#ifndef MODULE
static struct {
struct asymmetric_key_id id;
unsigned char data[10];
} cakey;
static int __init ca_keys_setup(char *str)
{
if (!str) /* default system keyring */
return 1;
if (strncmp(str, "id:", 3) == 0) {
struct asymmetric_key_id *p = &cakey.id;
size_t hexlen = (strlen(str) - 3) / 2;
int ret;
if (hexlen == 0 || hexlen > sizeof(cakey.data)) {
pr_err("Missing or invalid ca_keys id\n");
return 1;
}
ret = __asymmetric_key_hex_to_key_id(str + 3, p, hexlen);
if (ret < 0)
pr_err("Unparsable ca_keys id hex string\n");
else
ca_keyid = p; /* owner key 'id:xxxxxx' */
} else if (strcmp(str, "builtin") == 0) {
use_builtin_keys = true;
}
return 1;
}
__setup("ca_keys=", ca_keys_setup);
#endif
/**
* x509_request_asymmetric_key - Request a key by X.509 certificate params.
* @keyring: The keys to search.
* @id: The issuer & serialNumber to look for or NULL.
* @skid: The subjectKeyIdentifier to look for or NULL.
* @partial: Use partial match if true, exact if false.
*
* Find a key in the given keyring by identifier. The preferred identifier is
* the issuer + serialNumber and the fallback identifier is the
* subjectKeyIdentifier. If both are given, the lookup is by the former, but
* the latter must also match.
*/
struct key *x509_request_asymmetric_key(struct key *keyring,
const struct asymmetric_key_id *id,
const struct asymmetric_key_id *skid,
bool partial)
{
struct key *key;
key_ref_t ref;
const char *lookup;
char *req, *p;
int len;
if (id) {
lookup = id->data;
len = id->len;
} else {
lookup = skid->data;
len = skid->len;
}
/* Construct an identifier "id:<keyid>". */
p = req = kmalloc(2 + 1 + len * 2 + 1, GFP_KERNEL);
if (!req)
return ERR_PTR(-ENOMEM);
if (partial) {
*p++ = 'i';
*p++ = 'd';
} else {
*p++ = 'e';
*p++ = 'x';
}
*p++ = ':';
p = bin2hex(p, lookup, len);
*p = 0;
pr_debug("Look up: \"%s\"\n", req);
ref = keyring_search(make_key_ref(keyring, 1),
&key_type_asymmetric, req);
if (IS_ERR(ref))
pr_debug("Request for key '%s' err %ld\n", req, PTR_ERR(ref));
kfree(req);
if (IS_ERR(ref)) {
switch (PTR_ERR(ref)) {
/* Hide some search errors */
case -EACCES:
case -ENOTDIR:
case -EAGAIN:
return ERR_PTR(-ENOKEY);
default:
return ERR_CAST(ref);
}
}
key = key_ref_to_ptr(ref);
if (id && skid) {
const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
if (!kids->id[1]) {
pr_debug("issuer+serial match, but expected SKID missing\n");
goto reject;
}
if (!asymmetric_key_id_same(skid, kids->id[1])) {
pr_debug("issuer+serial match, but SKID does not\n");
goto reject;
}
}
pr_devel("<==%s() = 0 [%x]\n", __func__, key_serial(key));
return key;
reject:
key_put(key);
return ERR_PTR(-EKEYREJECTED);
}
EXPORT_SYMBOL_GPL(x509_request_asymmetric_key);
/*
* Set up the signature parameters in an X.509 certificate. This involves
* digesting the signed data and extracting the signature.
*/
int x509_get_sig_params(struct x509_certificate *cert)
{
struct public_key_signature *sig = cert->sig;
struct crypto_shash *tfm;
struct shash_desc *desc;
size_t digest_size, desc_size;
void *digest;
size_t desc_size;
int ret;
pr_devel("==>%s()\n", __func__);
if (cert->unsupported_crypto)
return -ENOPKG;
if (cert->sig.s)
return 0;
if (!cert->pub->pkey_algo)
cert->unsupported_key = true;
cert->sig.s = kmemdup(cert->raw_sig, cert->raw_sig_size,
GFP_KERNEL);
if (!cert->sig.s)
if (!sig->pkey_algo)
cert->unsupported_sig = true;
/* We check the hash if we can - even if we can't then verify it */
if (!sig->hash_algo) {
cert->unsupported_sig = true;
return 0;
}
sig->s = kmemdup(cert->raw_sig, cert->raw_sig_size, GFP_KERNEL);
if (!sig->s)
return -ENOMEM;
cert->sig.s_size = cert->raw_sig_size;
sig->s_size = cert->raw_sig_size;
/* Allocate the hashing algorithm we're going to need and find out how
* big the hash operational data will be.
*/
tfm = crypto_alloc_shash(cert->sig.hash_algo, 0, 0);
tfm = crypto_alloc_shash(sig->hash_algo, 0, 0);
if (IS_ERR(tfm)) {
if (PTR_ERR(tfm) == -ENOENT) {
cert->unsupported_crypto = true;
return -ENOPKG;
cert->unsupported_sig = true;
return 0;
}
return PTR_ERR(tfm);
}
desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
digest_size = crypto_shash_digestsize(tfm);
sig->digest_size = crypto_shash_digestsize(tfm);
/* We allocate the hash operational data storage on the end of the
* digest storage space.
*/
ret = -ENOMEM;
digest = kzalloc(ALIGN(digest_size, __alignof__(*desc)) + desc_size,
GFP_KERNEL);
if (!digest)
sig->digest = kmalloc(sig->digest_size, GFP_KERNEL);
if (!sig->digest)
goto error;
cert->sig.digest = digest;
cert->sig.digest_size = digest_size;
desc = kzalloc(desc_size, GFP_KERNEL);
if (!desc)
goto error;
desc = PTR_ALIGN(digest + digest_size, __alignof__(*desc));
desc->tfm = tfm;
desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
ret = crypto_shash_init(desc);
if (ret < 0)
goto error;
goto error_2;
might_sleep();
ret = crypto_shash_finup(desc, cert->tbs, cert->tbs_size, digest);
ret = crypto_shash_finup(desc, cert->tbs, cert->tbs_size, sig->digest);
error_2:
kfree(desc);
error:
crypto_free_shash(tfm);
pr_devel("<==%s() = %d\n", __func__, ret);
return ret;
}
EXPORT_SYMBOL_GPL(x509_get_sig_params);
/*
* Check the signature on a certificate using the provided public key
* Check for self-signedness in an X.509 cert and if found, check the signature
* immediately if we can.
*/
int x509_check_signature(const struct public_key *pub,
struct x509_certificate *cert)
int x509_check_for_self_signed(struct x509_certificate *cert)
{
int ret;
int ret = 0;
pr_devel("==>%s()\n", __func__);
ret = x509_get_sig_params(cert);
if (ret < 0)
return ret;
if (cert->raw_subject_size != cert->raw_issuer_size ||
memcmp(cert->raw_subject, cert->raw_issuer,
cert->raw_issuer_size) != 0)
goto not_self_signed;
ret = public_key_verify_signature(pub, &cert->sig);
if (ret == -ENOPKG)
cert->unsupported_crypto = true;
pr_debug("Cert Verification: %d\n", ret);
return ret;
}
EXPORT_SYMBOL_GPL(x509_check_signature);
if (cert->sig->auth_ids[0] || cert->sig->auth_ids[1]) {
/* If the AKID is present it may have one or two parts. If
* both are supplied, both must match.
*/
bool a = asymmetric_key_id_same(cert->skid, cert->sig->auth_ids[1]);
bool b = asymmetric_key_id_same(cert->id, cert->sig->auth_ids[0]);
/*
* Check the new certificate against the ones in the trust keyring. If one of
* those is the signing key and validates the new certificate, then mark the
* new certificate as being trusted.
*
* Return 0 if the new certificate was successfully validated, 1 if we couldn't
* find a matching parent certificate in the trusted list and an error if there
* is a matching certificate but the signature check fails.
*/
static int x509_validate_trust(struct x509_certificate *cert,
struct key *trust_keyring)
{
struct key *key;
int ret = 1;
if (!a && !b)
goto not_self_signed;
if (!trust_keyring)
return -EOPNOTSUPP;
if (ca_keyid && !asymmetric_key_id_partial(cert->akid_skid, ca_keyid))
return -EPERM;
key = x509_request_asymmetric_key(trust_keyring,
cert->akid_id, cert->akid_skid,
false);
if (!IS_ERR(key)) {
if (!use_builtin_keys
|| test_bit(KEY_FLAG_BUILTIN, &key->flags))
ret = x509_check_signature(key->payload.data[asym_crypto],
cert);
key_put(key);
ret = -EKEYREJECTED;
if (((a && !b) || (b && !a)) &&
cert->sig->auth_ids[0] && cert->sig->auth_ids[1])
goto out;
}
ret = -EKEYREJECTED;
if (cert->pub->pkey_algo != cert->sig->pkey_algo)
goto out;
ret = public_key_verify_signature(cert->pub, cert->sig);
if (ret < 0) {
if (ret == -ENOPKG) {
cert->unsupported_sig = true;
ret = 0;
}
goto out;
}
pr_devel("Cert Self-signature verified");
cert->self_signed = true;
out:
pr_devel("<==%s() = %d\n", __func__, ret);
return ret;
not_self_signed:
pr_devel("<==%s() = 0 [not]\n", __func__);
return 0;
}
/*
@@ -291,34 +168,22 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
pr_devel("Cert Issuer: %s\n", cert->issuer);
pr_devel("Cert Subject: %s\n", cert->subject);
if (!cert->pub->pkey_algo ||
!cert->sig.pkey_algo ||
!cert->sig.hash_algo) {
if (cert->unsupported_key) {
ret = -ENOPKG;
goto error_free_cert;
}
pr_devel("Cert Key Algo: %s\n", cert->pub->pkey_algo);
pr_devel("Cert Valid period: %lld-%lld\n", cert->valid_from, cert->valid_to);
pr_devel("Cert Signature: %s + %s\n",
cert->sig.pkey_algo,
cert->sig.hash_algo);
cert->pub->id_type = "X509";
/* Check the signature on the key if it appears to be self-signed */
if ((!cert->akid_skid && !cert->akid_id) ||
asymmetric_key_id_same(cert->skid, cert->akid_skid) ||
asymmetric_key_id_same(cert->id, cert->akid_id)) {
ret = x509_check_signature(cert->pub, cert); /* self-signed */
if (ret < 0)
goto error_free_cert;
} else if (!prep->trusted) {
ret = x509_validate_trust(cert, get_system_trusted_keyring());
if (ret)
ret = x509_validate_trust(cert, get_ima_mok_keyring());
if (!ret)
prep->trusted = 1;
if (cert->unsupported_sig) {
public_key_signature_free(cert->sig);
cert->sig = NULL;
} else {
pr_devel("Cert Signature: %s + %s\n",
cert->sig->pkey_algo, cert->sig->hash_algo);
}
/* Propose a description */
@@ -353,6 +218,7 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
prep->payload.data[asym_subtype] = &public_key_subtype;
prep->payload.data[asym_key_ids] = kids;
prep->payload.data[asym_crypto] = cert->pub;
prep->payload.data[asym_auth] = cert->sig;
prep->description = desc;
prep->quotalen = 100;
@@ -360,6 +226,7 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
cert->pub = NULL;
cert->id = NULL;
cert->skid = NULL;
cert->sig = NULL;
desc = NULL;
ret = 0;