diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-21 20:44:37 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-21 20:44:37 -0700 |
commit | 7f313ff0acdecf0926ab127533a2a93948a2f547 (patch) | |
tree | a82dc675035d735820656c7fa21ed409b257bd4b /security | |
parent | 2c5a5358feff2c1e035a67a9b352c4358e669e5b (diff) | |
parent | 4a48b4c428dc92b5e0b19de83e7eb8d530dddd48 (diff) | |
download | linux-7f313ff0acdecf0926ab127533a2a93948a2f547.tar.bz2 |
Merge tag 'integrity-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity subsystem updates from Mimi Zohar:
"Except for extending the 'encrypted' key type to support user provided
data, the rest is code cleanup, __setup() usage bug fix, and a trivial
change"
* tag 'integrity-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
MAINTAINERS: add missing security/integrity/platform_certs
EVM: fix the evm= __setup handler return value
KEYS: encrypted: Instantiate key with user-provided decrypted data
ima: define ima_max_digest_data struct without a flexible array variable
ima: rename IMA_ACTION_FLAGS to IMA_NONACTION_FLAGS
ima: Return error code obtained from securityfs functions
MAINTAINERS: add missing "security/integrity" directory
ima: Fix trivial typos in the comments
Diffstat (limited to 'security')
-rw-r--r-- | security/integrity/evm/evm_main.c | 2 | ||||
-rw-r--r-- | security/integrity/ima/ima_api.c | 12 | ||||
-rw-r--r-- | security/integrity/ima/ima_fs.c | 31 | ||||
-rw-r--r-- | security/integrity/ima/ima_init.c | 5 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 9 | ||||
-rw-r--r-- | security/integrity/ima/ima_policy.c | 4 | ||||
-rw-r--r-- | security/integrity/ima/ima_template_lib.c | 7 | ||||
-rw-r--r-- | security/integrity/integrity.h | 14 | ||||
-rw-r--r-- | security/keys/Kconfig | 19 | ||||
-rw-r--r-- | security/keys/encrypted-keys/encrypted.c | 71 |
10 files changed, 116 insertions, 58 deletions
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 08f907382c61..7d87772f0ce6 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -86,7 +86,7 @@ static int __init evm_set_fixmode(char *str) else pr_err("invalid \"%s\" mode", str); - return 0; + return 1; } __setup("evm=", evm_set_fixmode); diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index a64fb0130b01..c6805af46211 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -217,14 +217,11 @@ int ima_collect_measurement(struct integrity_iint_cache *iint, const char *audit_cause = "failed"; struct inode *inode = file_inode(file); const char *filename = file->f_path.dentry->d_name.name; + struct ima_max_digest_data hash; int result = 0; int length; void *tmpbuf; u64 i_version; - struct { - struct ima_digest_data hdr; - char digest[IMA_MAX_DIGEST_SIZE]; - } hash; /* * Always collect the modsig, because IMA might have already collected @@ -238,9 +235,10 @@ int ima_collect_measurement(struct integrity_iint_cache *iint, goto out; /* - * Dectecting file change is based on i_version. On filesystems - * which do not support i_version, support is limited to an initial - * measurement/appraisal/audit. + * Detecting file change is based on i_version. On filesystems + * which do not support i_version, support was originally limited + * to an initial measurement/appraisal/audit, but was modified to + * assume the file changed. */ i_version = inode_query_iversion(inode); hash.hdr.algo = algo; diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 3ad8f7734208..cd1683dad3bf 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -452,47 +452,61 @@ static const struct file_operations ima_measure_policy_ops = { int __init ima_fs_init(void) { + int ret; + ima_dir = securityfs_create_dir("ima", integrity_dir); if (IS_ERR(ima_dir)) - return -1; + return PTR_ERR(ima_dir); ima_symlink = securityfs_create_symlink("ima", NULL, "integrity/ima", NULL); - if (IS_ERR(ima_symlink)) + if (IS_ERR(ima_symlink)) { + ret = PTR_ERR(ima_symlink); goto out; + } binary_runtime_measurements = securityfs_create_file("binary_runtime_measurements", S_IRUSR | S_IRGRP, ima_dir, NULL, &ima_measurements_ops); - if (IS_ERR(binary_runtime_measurements)) + if (IS_ERR(binary_runtime_measurements)) { + ret = PTR_ERR(binary_runtime_measurements); goto out; + } ascii_runtime_measurements = securityfs_create_file("ascii_runtime_measurements", S_IRUSR | S_IRGRP, ima_dir, NULL, &ima_ascii_measurements_ops); - if (IS_ERR(ascii_runtime_measurements)) + if (IS_ERR(ascii_runtime_measurements)) { + ret = PTR_ERR(ascii_runtime_measurements); goto out; + } runtime_measurements_count = securityfs_create_file("runtime_measurements_count", S_IRUSR | S_IRGRP, ima_dir, NULL, &ima_measurements_count_ops); - if (IS_ERR(runtime_measurements_count)) + if (IS_ERR(runtime_measurements_count)) { + ret = PTR_ERR(runtime_measurements_count); goto out; + } violations = securityfs_create_file("violations", S_IRUSR | S_IRGRP, ima_dir, NULL, &ima_htable_violations_ops); - if (IS_ERR(violations)) + if (IS_ERR(violations)) { + ret = PTR_ERR(violations); goto out; + } ima_policy = securityfs_create_file("policy", POLICY_FILE_FLAGS, ima_dir, NULL, &ima_measure_policy_ops); - if (IS_ERR(ima_policy)) + if (IS_ERR(ima_policy)) { + ret = PTR_ERR(ima_policy); goto out; + } return 0; out: @@ -503,5 +517,6 @@ out: securityfs_remove(binary_runtime_measurements); securityfs_remove(ima_symlink); securityfs_remove(ima_dir); - return -1; + + return ret; } diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c index b26fa67476b4..63979aefc95f 100644 --- a/security/integrity/ima/ima_init.c +++ b/security/integrity/ima/ima_init.c @@ -47,12 +47,9 @@ static int __init ima_add_boot_aggregate(void) struct integrity_iint_cache tmp_iint, *iint = &tmp_iint; struct ima_event_data event_data = { .iint = iint, .filename = boot_aggregate_name }; + struct ima_max_digest_data hash; int result = -ENOMEM; int violation = 0; - struct { - struct ima_digest_data hdr; - char digest[TPM_MAX_DIGEST_SIZE]; - } hash; memset(iint, 0, sizeof(*iint)); memset(&hash, 0, sizeof(hash)); diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 8c6e4514d494..c6412dec3810 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -263,7 +263,7 @@ static int process_measurement(struct file *file, const struct cred *cred, /* reset appraisal flags if ima_inode_post_setattr was called */ iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED | IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK | - IMA_ACTION_FLAGS); + IMA_NONACTION_FLAGS); /* * Re-evaulate the file if either the xattr has changed or the @@ -764,7 +764,7 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, * call to ima_post_load_data(). * * Callers of this LSM hook can not measure, appraise, or audit the - * data provided by userspace. Enforce policy rules requring a file + * data provided by userspace. Enforce policy rules requiring a file * signature (eg. kexec'ed kernel image). * * For permission return 0, otherwise return -EACCES. @@ -874,10 +874,7 @@ int process_buffer_measurement(struct user_namespace *mnt_userns, .buf = buf, .buf_len = size}; struct ima_template_desc *template; - struct { - struct ima_digest_data hdr; - char digest[IMA_MAX_DIGEST_SIZE]; - } hash = {}; + struct ima_max_digest_data hash; char digest_hash[IMA_MAX_DIGEST_SIZE]; int digest_hash_len = hash_digest_size[ima_hash_algo]; int violation = 0; diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 99d23ac4c35d..eea6e92500b8 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -428,7 +428,7 @@ static int ima_lsm_update_rule(struct ima_rule_entry *entry) /* * ima_lsm_copy_rule() shallow copied all references, except for the * LSM references, from entry to nentry so we only want to free the LSM - * references and the entry itself. All other memory refrences will now + * references and the entry itself. All other memory references will now * be owned by nentry. */ ima_lsm_free_rule(entry); @@ -711,7 +711,7 @@ int ima_match_policy(struct user_namespace *mnt_userns, struct inode *inode, func, mask, func_data)) continue; - action |= entry->flags & IMA_ACTION_FLAGS; + action |= entry->flags & IMA_NONACTION_FLAGS; action |= entry->action & IMA_DO_MASK; if (entry->action & IMA_APPRAISE) { diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c index ca017cae73eb..7155d17a3b75 100644 --- a/security/integrity/ima/ima_template_lib.c +++ b/security/integrity/ima/ima_template_lib.c @@ -272,7 +272,7 @@ static int ima_eventdigest_init_common(const u8 *digest, u32 digestsize, * digest formats: * - DATA_FMT_DIGEST: digest * - DATA_FMT_DIGEST_WITH_ALGO: [<hash algo>] + ':' + '\0' + digest, - * where <hash algo> is provided if the hash algoritm is not + * where <hash algo> is provided if the hash algorithm is not * SHA1 or MD5 */ u8 buffer[CRYPTO_MAX_ALG_NAME + 2 + IMA_MAX_DIGEST_SIZE] = { 0 }; @@ -307,10 +307,7 @@ static int ima_eventdigest_init_common(const u8 *digest, u32 digestsize, int ima_eventdigest_init(struct ima_event_data *event_data, struct ima_field_data *field_data) { - struct { - struct ima_digest_data hdr; - char digest[IMA_MAX_DIGEST_SIZE]; - } hash; + struct ima_max_digest_data hash; u8 *cur_digest = NULL; u32 cur_digestsize = 0; struct inode *inode; diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 2e214c761158..3510e413ea17 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -15,6 +15,7 @@ #include <linux/types.h> #include <linux/integrity.h> #include <crypto/sha1.h> +#include <crypto/hash.h> #include <linux/key.h> #include <linux/audit.h> @@ -30,8 +31,8 @@ #define IMA_HASH 0x00000100 #define IMA_HASHED 0x00000200 -/* iint cache flags */ -#define IMA_ACTION_FLAGS 0xff000000 +/* iint policy rule cache flags */ +#define IMA_NONACTION_FLAGS 0xff000000 #define IMA_DIGSIG_REQUIRED 0x01000000 #define IMA_PERMIT_DIRECTIO 0x02000000 #define IMA_NEW_FILE 0x04000000 @@ -111,6 +112,15 @@ struct ima_digest_data { } __packed; /* + * Instead of wrapping the ima_digest_data struct inside a local structure + * with the maximum hash size, define ima_max_digest_data struct. + */ +struct ima_max_digest_data { + struct ima_digest_data hdr; + u8 digest[HASH_MAX_DIGESTSIZE]; +} __packed; + +/* * signature format v2 - for using with asymmetric keys */ struct signature_v2_hdr { diff --git a/security/keys/Kconfig b/security/keys/Kconfig index 969122c7b92f..0e30b361e1c1 100644 --- a/security/keys/Kconfig +++ b/security/keys/Kconfig @@ -98,10 +98,21 @@ 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. diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c index 87432b35d771..e05cfc2e49ae 100644 --- a/security/keys/encrypted-keys/encrypted.c +++ b/security/keys/encrypted-keys/encrypted.c @@ -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: @@ -595,7 +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; @@ -604,6 +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); @@ -613,6 +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) { @@ -740,13 +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; @@ -760,21 +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. */ @@ -787,6 +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; @@ -799,18 +832,18 @@ 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) { kfree_sensitive(epayload); goto out; @@ -860,7 +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; @@ -869,7 +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; |