diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-11-21 19:46:00 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-11-21 19:46:00 -0800 |
commit | 78dc53c422172a317adb0776dfb687057ffa28b7 (patch) | |
tree | 7c5d15da75d769d01f6a992c24c3490b3867d5b2 /security/integrity | |
parent | 3eaded86ac3e7f00fb3eeb8162d89e9a34e42fb0 (diff) | |
parent | 62fe318256befbd1b4a6765e71d9c997f768fe79 (diff) |
Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"In this patchset, we finally get an SELinux update, with Paul Moore
taking over as maintainer of that code.
Also a significant update for the Keys subsystem, as well as
maintenance updates to Smack, IMA, TPM, and Apparmor"
and since I wanted to know more about the updates to key handling,
here's the explanation from David Howells on that:
"Okay. There are a number of separate bits. I'll go over the big bits
and the odd important other bit, most of the smaller bits are just
fixes and cleanups. If you want the small bits accounting for, I can
do that too.
(1) Keyring capacity expansion.
KEYS: Consolidate the concept of an 'index key' for key access
KEYS: Introduce a search context structure
KEYS: Search for auth-key by name rather than target key ID
Add a generic associative array implementation.
KEYS: Expand the capacity of a keyring
Several of the patches are providing an expansion of the capacity of a
keyring. Currently, the maximum size of a keyring payload is one page.
Subtract a small header and then divide up into pointers, that only gives
you ~500 pointers on an x86_64 box. However, since the NFS idmapper uses
a keyring to store ID mapping data, that has proven to be insufficient to
the cause.
Whatever data structure I use to handle the keyring payload, it can only
store pointers to keys, not the keys themselves because several keyrings
may point to a single key. This precludes inserting, say, and rb_node
struct into the key struct for this purpose.
I could make an rbtree of records such that each record has an rb_node
and a key pointer, but that would use four words of space per key stored
in the keyring. It would, however, be able to use much existing code.
I selected instead a non-rebalancing radix-tree type approach as that
could have a better space-used/key-pointer ratio. I could have used the
radix tree implementation that we already have and insert keys into it by
their serial numbers, but that means any sort of search must iterate over
the whole radix tree. Further, its nodes are a bit on the capacious side
for what I want - especially given that key serial numbers are randomly
allocated, thus leaving a lot of empty space in the tree.
So what I have is an associative array that internally is a radix-tree
with 16 pointers per node where the index key is constructed from the key
type pointer and the key description. This means that an exact lookup by
type+description is very fast as this tells us how to navigate directly to
the target key.
I made the data structure general in lib/assoc_array.c as far as it is
concerned, its index key is just a sequence of bits that leads to a
pointer. It's possible that someone else will be able to make use of it
also. FS-Cache might, for example.
(2) Mark keys as 'trusted' and keyrings as 'trusted only'.
KEYS: verify a certificate is signed by a 'trusted' key
KEYS: Make the system 'trusted' keyring viewable by userspace
KEYS: Add a 'trusted' flag and a 'trusted only' flag
KEYS: Separate the kernel signature checking keyring from module signing
These patches allow keys carrying asymmetric public keys to be marked as
being 'trusted' and allow keyrings to be marked as only permitting the
addition or linkage of trusted keys.
Keys loaded from hardware during kernel boot or compiled into the kernel
during build are marked as being trusted automatically. New keys can be
loaded at runtime with add_key(). They are checked against the system
keyring contents and if their signatures can be validated with keys that
are already marked trusted, then they are marked trusted also and can
thus be added into the master keyring.
Patches from Mimi Zohar make this usable with the IMA keyrings also.
(3) Remove the date checks on the key used to validate a module signature.
X.509: Remove certificate date checks
It's not reasonable to reject a signature just because the key that it was
generated with is no longer valid datewise - especially if the kernel
hasn't yet managed to set the system clock when the first module is
loaded - so just remove those checks.
(4) Make it simpler to deal with additional X.509 being loaded into the kernel.
KEYS: Load *.x509 files into kernel keyring
KEYS: Have make canonicalise the paths of the X.509 certs better to deduplicate
The builder of the kernel now just places files with the extension ".x509"
into the kernel source or build trees and they're concatenated by the
kernel build and stuffed into the appropriate section.
(5) Add support for userspace kerberos to use keyrings.
KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches
KEYS: Implement a big key type that can save to tmpfs
Fedora went to, by default, storing kerberos tickets and tokens in tmpfs.
We looked at storing it in keyrings instead as that confers certain
advantages such as tickets being automatically deleted after a certain
amount of time and the ability for the kernel to get at these tokens more
easily.
To make this work, two things were needed:
(a) A way for the tickets to persist beyond the lifetime of all a user's
sessions so that cron-driven processes can still use them.
The problem is that a user's session keyrings are deleted when the
session that spawned them logs out and the user's user keyring is
deleted when the UID is deleted (typically when the last log out
happens), so neither of these places is suitable.
I've added a system keyring into which a 'persistent' keyring is
created for each UID on request. Each time a user requests their
persistent keyring, the expiry time on it is set anew. If the user
doesn't ask for it for, say, three days, the keyring is automatically
expired and garbage collected using the existing gc. All the kerberos
tokens it held are then also gc'd.
(b) A key type that can hold really big tickets (up to 1MB in size).
The problem is that Active Directory can return huge tickets with lots
of auxiliary data attached. We don't, however, want to eat up huge
tracts of unswappable kernel space for this, so if the ticket is
greater than a certain size, we create a swappable shmem file and dump
the contents in there and just live with the fact we then have an
inode and a dentry overhead. If the ticket is smaller than that, we
slap it in a kmalloc()'d buffer"
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (121 commits)
KEYS: Fix keyring content gc scanner
KEYS: Fix error handling in big_key instantiation
KEYS: Fix UID check in keyctl_get_persistent()
KEYS: The RSA public key algorithm needs to select MPILIB
ima: define '_ima' as a builtin 'trusted' keyring
ima: extend the measurement list to include the file signature
kernel/system_certificate.S: use real contents instead of macro GLOBAL()
KEYS: fix error return code in big_key_instantiate()
KEYS: Fix keyring quota misaccounting on key replacement and unlink
KEYS: Fix a race between negating a key and reading the error set
KEYS: Make BIG_KEYS boolean
apparmor: remove the "task" arg from may_change_ptraced_domain()
apparmor: remove parent task info from audit logging
apparmor: remove tsk field from the apparmor_audit_struct
apparmor: fix capability to not use the current task, during reporting
Smack: Ptrace access check mode
ima: provide hash algo info in the xattr
ima: enable support for larger default filedata hash algorithms
ima: define kernel parameter 'ima_template=' to change configured default
ima: add Kconfig default measurement list template
...
Diffstat (limited to 'security/integrity')
-rw-r--r-- | security/integrity/digsig.c | 37 | ||||
-rw-r--r-- | security/integrity/digsig_asymmetric.c | 11 | ||||
-rw-r--r-- | security/integrity/evm/evm_main.c | 4 | ||||
-rw-r--r-- | security/integrity/evm/evm_posix_acl.c | 3 | ||||
-rw-r--r-- | security/integrity/iint.c | 2 | ||||
-rw-r--r-- | security/integrity/ima/Kconfig | 72 | ||||
-rw-r--r-- | security/integrity/ima/Makefile | 2 | ||||
-rw-r--r-- | security/integrity/ima/ima.h | 101 | ||||
-rw-r--r-- | security/integrity/ima/ima_api.c | 136 | ||||
-rw-r--r-- | security/integrity/ima/ima_appraise.c | 117 | ||||
-rw-r--r-- | security/integrity/ima/ima_crypto.c | 134 | ||||
-rw-r--r-- | security/integrity/ima/ima_fs.c | 67 | ||||
-rw-r--r-- | security/integrity/ima/ima_init.c | 37 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 63 | ||||
-rw-r--r-- | security/integrity/ima/ima_policy.c | 1 | ||||
-rw-r--r-- | security/integrity/ima/ima_queue.c | 10 | ||||
-rw-r--r-- | security/integrity/ima/ima_template.c | 178 | ||||
-rw-r--r-- | security/integrity/ima/ima_template_lib.c | 347 | ||||
-rw-r--r-- | security/integrity/ima/ima_template_lib.h | 49 | ||||
-rw-r--r-- | security/integrity/integrity.h | 47 |
20 files changed, 1237 insertions, 181 deletions
diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c index 0b759e17a131..77ca965ab684 100644 --- a/security/integrity/digsig.c +++ b/security/integrity/digsig.c @@ -13,7 +13,9 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/err.h> +#include <linux/sched.h> #include <linux/rbtree.h> +#include <linux/cred.h> #include <linux/key-type.h> #include <linux/digsig.h> @@ -21,21 +23,29 @@ static struct key *keyring[INTEGRITY_KEYRING_MAX]; +#ifdef CONFIG_IMA_TRUSTED_KEYRING +static const char *keyring_name[INTEGRITY_KEYRING_MAX] = { + ".evm", + ".module", + ".ima", +}; +#else static const char *keyring_name[INTEGRITY_KEYRING_MAX] = { "_evm", "_module", "_ima", }; +#endif int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, - const char *digest, int digestlen) + const char *digest, int digestlen) { if (id >= INTEGRITY_KEYRING_MAX) return -EINVAL; if (!keyring[id]) { keyring[id] = - request_key(&key_type_keyring, keyring_name[id], NULL); + request_key(&key_type_keyring, keyring_name[id], NULL); if (IS_ERR(keyring[id])) { int err = PTR_ERR(keyring[id]); pr_err("no %s keyring: %d\n", keyring_name[id], err); @@ -44,9 +54,10 @@ int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, } } - switch (sig[0]) { + switch (sig[1]) { case 1: - return digsig_verify(keyring[id], sig, siglen, + /* v1 API expect signature without xattr type */ + return digsig_verify(keyring[id], sig + 1, siglen - 1, digest, digestlen); case 2: return asymmetric_verify(keyring[id], sig, siglen, @@ -55,3 +66,21 @@ int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, return -EOPNOTSUPP; } + +int integrity_init_keyring(const unsigned int id) +{ + const struct cred *cred = current_cred(); + const struct user_struct *user = cred->user; + + keyring[id] = keyring_alloc(keyring_name[id], KUIDT_INIT(0), + KGIDT_INIT(0), cred, + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ), + KEY_ALLOC_NOT_IN_QUOTA, user->uid_keyring); + if (!IS_ERR(keyring[id])) + set_bit(KEY_FLAG_TRUSTED_ONLY, &keyring[id]->flags); + else + pr_info("Can't allocate %s keyring (%ld)\n", + keyring_name[id], PTR_ERR(keyring[id])); + return 0; +} diff --git a/security/integrity/digsig_asymmetric.c b/security/integrity/digsig_asymmetric.c index b4754667659d..9eae4809006b 100644 --- a/security/integrity/digsig_asymmetric.c +++ b/security/integrity/digsig_asymmetric.c @@ -20,17 +20,6 @@ #include "integrity.h" /* - * signature format v2 - for using with asymmetric keys - */ -struct signature_v2_hdr { - uint8_t version; /* signature format version */ - uint8_t hash_algo; /* Digest algorithm [enum pkey_hash_algo] */ - uint32_t keyid; /* IMA key identifier - not X509/PGP specific*/ - uint16_t sig_size; /* signature size */ - uint8_t sig[0]; /* signature payload */ -} __packed; - -/* * Request an asymmetric key. */ static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid) diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index af9b6852f4e1..336b3ddfe63f 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -123,7 +123,7 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, goto out; } - xattr_len = rc - 1; + xattr_len = rc; /* check value type */ switch (xattr_data->type) { @@ -143,7 +143,7 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, if (rc) break; rc = integrity_digsig_verify(INTEGRITY_KEYRING_EVM, - xattr_data->digest, xattr_len, + (const char *)xattr_data, xattr_len, calc.digest, sizeof(calc.digest)); if (!rc) { /* we probably want to replace rsa with hmac here */ diff --git a/security/integrity/evm/evm_posix_acl.c b/security/integrity/evm/evm_posix_acl.c index b1753e98bf9a..46408b9e62e8 100644 --- a/security/integrity/evm/evm_posix_acl.c +++ b/security/integrity/evm/evm_posix_acl.c @@ -11,8 +11,9 @@ #include <linux/module.h> #include <linux/xattr.h> +#include <linux/evm.h> -int posix_xattr_acl(char *xattr) +int posix_xattr_acl(const char *xattr) { int xattr_len = strlen(xattr); diff --git a/security/integrity/iint.c b/security/integrity/iint.c index 74522dbd10a6..c49d3f14cbec 100644 --- a/security/integrity/iint.c +++ b/security/integrity/iint.c @@ -70,6 +70,8 @@ struct integrity_iint_cache *integrity_iint_find(struct inode *inode) static void iint_free(struct integrity_iint_cache *iint) { + kfree(iint->ima_hash); + iint->ima_hash = NULL; iint->version = 0; iint->flags = 0UL; iint->ima_file_status = INTEGRITY_UNKNOWN; diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index 39196abaff0d..dad8d4ca2437 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -9,6 +9,7 @@ config IMA select CRYPTO_HMAC select CRYPTO_MD5 select CRYPTO_SHA1 + select CRYPTO_HASH_INFO select TCG_TPM if HAS_IOMEM && !UML select TCG_TIS if TCG_TPM && X86 select TCG_IBMVTPM if TCG_TPM && PPC64 @@ -45,6 +46,69 @@ config IMA_LSM_RULES help Disabling this option will disregard LSM based policy rules. +choice + prompt "Default template" + default IMA_NG_TEMPLATE + depends on IMA + help + Select the default IMA measurement template. + + The original 'ima' measurement list template contains a + hash, defined as 20 bytes, and a null terminated pathname, + limited to 255 characters. The 'ima-ng' measurement list + template permits both larger hash digests and longer + pathnames. + + config IMA_TEMPLATE + bool "ima" + config IMA_NG_TEMPLATE + bool "ima-ng (default)" + config IMA_SIG_TEMPLATE + bool "ima-sig" +endchoice + +config IMA_DEFAULT_TEMPLATE + string + depends on IMA + default "ima" if IMA_TEMPLATE + default "ima-ng" if IMA_NG_TEMPLATE + default "ima-sig" if IMA_SIG_TEMPLATE + +choice + prompt "Default integrity hash algorithm" + default IMA_DEFAULT_HASH_SHA1 + depends on IMA + help + Select the default hash algorithm used for the measurement + list, integrity appraisal and audit log. The compiled default + hash algorithm can be overwritten using the kernel command + line 'ima_hash=' option. + + config IMA_DEFAULT_HASH_SHA1 + bool "SHA1 (default)" + depends on CRYPTO_SHA1 + + config IMA_DEFAULT_HASH_SHA256 + bool "SHA256" + depends on CRYPTO_SHA256 && !IMA_TEMPLATE + + config IMA_DEFAULT_HASH_SHA512 + bool "SHA512" + depends on CRYPTO_SHA512 && !IMA_TEMPLATE + + config IMA_DEFAULT_HASH_WP512 + bool "WP512" + depends on CRYPTO_WP512 && !IMA_TEMPLATE +endchoice + +config IMA_DEFAULT_HASH + string + depends on IMA + default "sha1" if IMA_DEFAULT_HASH_SHA1 + default "sha256" if IMA_DEFAULT_HASH_SHA256 + default "sha512" if IMA_DEFAULT_HASH_SHA512 + default "wp512" if IMA_DEFAULT_HASH_WP512 + config IMA_APPRAISE bool "Appraise integrity measurements" depends on IMA @@ -59,3 +123,11 @@ config IMA_APPRAISE For more information on integrity appraisal refer to: <http://linux-ima.sourceforge.net> If unsure, say N. + +config IMA_TRUSTED_KEYRING + bool "Require all keys on the _ima keyring be signed" + depends on IMA_APPRAISE && SYSTEM_TRUSTED_KEYRING + default y + help + This option requires that all keys added to the _ima + keyring be signed by a key on the system trusted keyring. diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile index 56dfee7cbf61..d79263d2fdbf 100644 --- a/security/integrity/ima/Makefile +++ b/security/integrity/ima/Makefile @@ -6,5 +6,5 @@ obj-$(CONFIG_IMA) += ima.o ima-y := ima_fs.o ima_queue.o ima_init.o ima_main.o ima_crypto.o ima_api.o \ - ima_policy.o + ima_policy.o ima_template.o ima_template_lib.o ima-$(CONFIG_IMA_APPRAISE) += ima_appraise.o diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index b3dd616560f7..bf03c6a16cc8 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -36,23 +36,48 @@ enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 }; #define IMA_HASH_BITS 9 #define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS) +#define IMA_TEMPLATE_FIELD_ID_MAX_LEN 16 +#define IMA_TEMPLATE_NUM_FIELDS_MAX 15 + +#define IMA_TEMPLATE_IMA_NAME "ima" +#define IMA_TEMPLATE_IMA_FMT "d|n" + /* set during initialization */ extern int ima_initialized; extern int ima_used_chip; -extern char *ima_hash; +extern int ima_hash_algo; extern int ima_appraise; -/* IMA inode template definition */ -struct ima_template_data { - u8 digest[IMA_DIGEST_SIZE]; /* sha1/md5 measurement hash */ - char file_name[IMA_EVENT_NAME_LEN_MAX + 1]; /* name + \0 */ +/* IMA template field data definition */ +struct ima_field_data { + u8 *data; + u32 len; +}; + +/* IMA template field definition */ +struct ima_template_field { + const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; + int (*field_init) (struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, struct ima_field_data *field_data); + void (*field_show) (struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); +}; + +/* IMA template descriptor definition */ +struct ima_template_desc { + char *name; + char *fmt; + int num_fields; + struct ima_template_field **fields; }; struct ima_template_entry { - u8 digest[IMA_DIGEST_SIZE]; /* sha1 or md5 measurement hash */ - const char *template_name; - int template_len; - struct ima_template_data template; + u8 digest[TPM_DIGEST_SIZE]; /* sha1 or md5 measurement hash */ + struct ima_template_desc *template_desc; /* template descriptor */ + u32 template_data_len; + struct ima_field_data template_data[0]; /* template related data */ }; struct ima_queue_entry { @@ -69,13 +94,21 @@ int ima_fs_init(void); void ima_fs_cleanup(void); int ima_inode_alloc(struct inode *inode); int ima_add_template_entry(struct ima_template_entry *entry, int violation, - const char *op, struct inode *inode); -int ima_calc_file_hash(struct file *file, char *digest); -int ima_calc_buffer_hash(const void *data, int len, char *digest); -int ima_calc_boot_aggregate(char *digest); -void ima_add_violation(struct inode *inode, const unsigned char *filename, + const char *op, struct inode *inode, + const unsigned char *filename); +int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); +int ima_calc_field_array_hash(struct ima_field_data *field_data, int num_fields, + struct ima_digest_data *hash); +int __init ima_calc_boot_aggregate(struct ima_digest_data *hash); +void ima_add_violation(struct file *file, const unsigned char *filename, const char *op, const char *cause); int ima_init_crypto(void); +void ima_putc(struct seq_file *m, void *data, int datalen); +void ima_print_digest(struct seq_file *m, u8 *digest, int size); +struct ima_template_desc *ima_template_desc_current(void); +int ima_init_template(void); + +int ima_init_template(void); /* * used to protect h_table and sha_table @@ -98,14 +131,21 @@ static inline unsigned long ima_hash_key(u8 *digest) int ima_get_action(struct inode *inode, int mask, int function); int ima_must_measure(struct inode *inode, int mask, int function); int ima_collect_measurement(struct integrity_iint_cache *iint, - struct file *file); + struct file *file, + struct evm_ima_xattr_data **xattr_value, + int *xattr_len); void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, - const unsigned char *filename); + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len); void ima_audit_measurement(struct integrity_iint_cache *iint, const unsigned char *filename); +int ima_alloc_init_template(struct integrity_iint_cache *iint, + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, struct ima_template_entry **entry); int ima_store_template(struct ima_template_entry *entry, int violation, - struct inode *inode); -void ima_template_show(struct seq_file *m, void *e, enum ima_show_type show); + struct inode *inode, const unsigned char *filename); const char *ima_d_path(struct path *path, char **pathbuf); /* rbtree tree calls to lookup, insert, delete @@ -131,17 +171,25 @@ void ima_delete_rules(void); #ifdef CONFIG_IMA_APPRAISE int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, - struct file *file, const unsigned char *filename); + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len); int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, int func); +void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_digest_data *hash); +int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value); #else static inline int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, struct file *file, - const unsigned char *filename) + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len) { return INTEGRITY_UNKNOWN; } @@ -162,6 +210,19 @@ static inline enum integrity_status ima_get_cache_status(struct integrity_iint_c { return INTEGRITY_UNKNOWN; } + +static inline void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, + int xattr_len, + struct ima_digest_data *hash) +{ +} + +static inline int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value) +{ + return 0; +} + #endif /* LSM based policy rules require audit */ diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index 1c03e8f1e0e1..0e7540863fc2 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -18,9 +18,46 @@ #include <linux/fs.h> #include <linux/xattr.h> #include <linux/evm.h> +#include <crypto/hash_info.h> #include "ima.h" -static const char *IMA_TEMPLATE_NAME = "ima"; +/* + * ima_alloc_init_template - create and initialize a new template entry + */ +int ima_alloc_init_template(struct integrity_iint_cache *iint, + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, struct ima_template_entry **entry) +{ + struct ima_template_desc *template_desc = ima_template_desc_current(); + int i, result = 0; + + *entry = kzalloc(sizeof(**entry) + template_desc->num_fields * + sizeof(struct ima_field_data), GFP_NOFS); + if (!*entry) + return -ENOMEM; + + for (i = 0; i < template_desc->num_fields; i++) { + struct ima_template_field *field = template_desc->fields[i]; + u32 len; + + result = field->field_init(iint, file, filename, + xattr_value, xattr_len, + &((*entry)->template_data[i])); + if (result != 0) + goto out; + + len = (*entry)->template_data[i].len; + (*entry)->template_data_len += sizeof(len); + (*entry)->template_data_len += len; + } + (*entry)->template_desc = template_desc; + return 0; +out: + kfree(*entry); + *entry = NULL; + return result; +} /* * ima_store_template - store ima template measurements @@ -39,28 +76,34 @@ static const char *IMA_TEMPLATE_NAME = "ima"; * Returns 0 on success, error code otherwise */ int ima_store_template(struct ima_template_entry *entry, - int violation, struct inode *inode) + int violation, struct inode *inode, + const unsigned char *filename) { const char *op = "add_template_measure"; const char *audit_cause = "hashing_error"; + char *template_name = entry->template_desc->name; int result; - - memset(entry->digest, 0, sizeof(entry->digest)); - entry->template_name = IMA_TEMPLATE_NAME; - entry->template_len = sizeof(entry->template); + struct { + struct ima_digest_data hdr; + char digest[TPM_DIGEST_SIZE]; + } hash; if (!violation) { - result = ima_calc_buffer_hash(&entry->template, - entry->template_len, - entry->digest); + int num_fields = entry->template_desc->num_fields; + + /* this function uses default algo */ + hash.hdr.algo = HASH_ALGO_SHA1; + result = ima_calc_field_array_hash(&entry->template_data[0], + num_fields, &hash.hdr); if (result < 0) { integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, - entry->template_name, op, + template_name, op, audit_cause, result, 0); return result; } + memcpy(entry->digest, hash.hdr.digest, hash.hdr.length); } - result = ima_add_template_entry(entry, violation, op, inode); + result = ima_add_template_entry(entry, violation, op, inode, filename); return result; } @@ -71,24 +114,24 @@ int ima_store_template(struct ima_template_entry *entry, * By extending the PCR with 0xFF's instead of with zeroes, the PCR * value is invalidated. */ -void ima_add_violation(struct inode *inode, const unsigned char *filename, +void ima_add_violation(struct file *file, const unsigned char *filename, const char *op, const char *cause) { struct ima_template_entry *entry; + struct inode *inode = file->f_dentry->d_inode; int violation = 1; int result; /* can overflow, only indicator */ atomic_long_inc(&ima_htable.violations); - entry = kmalloc(sizeof(*entry), GFP_KERNEL); - if (!entry) { + result = ima_alloc_init_template(NULL, file, filename, + NULL, 0, &entry); + if (result < 0) { result = -ENOMEM; goto err_out; } - memset(&entry->template, 0, sizeof(entry->template)); - strncpy(entry->template.file_name, filename, IMA_EVENT_NAME_LEN_MAX); - result = ima_store_template(entry, violation, inode); + result = ima_store_template(entry, violation, inode, filename); if (result < 0) kfree(entry); err_out: @@ -138,20 +181,42 @@ int ima_must_measure(struct inode *inode, int mask, int function) * Return 0 on success, error code otherwise */ int ima_collect_measurement(struct integrity_iint_cache *iint, - struct file *file) + struct file *file, + struct evm_ima_xattr_data **xattr_value, + int *xattr_len) { struct inode *inode = file_inode(file); const char *filename = file->f_dentry->d_name.name; int result = 0; + struct { + struct ima_digest_data hdr; + char digest[IMA_MAX_DIGEST_SIZE]; + } hash; + + if (xattr_value) + *xattr_len = ima_read_xattr(file->f_dentry, xattr_value); if (!(iint->flags & IMA_COLLECTED)) { u64 i_version = file_inode(file)->i_version; - iint->ima_xattr.type = IMA_XATTR_DIGEST; - result = ima_calc_file_hash(file, iint->ima_xattr.digest); + /* use default hash algorithm */ + hash.hdr.algo = ima_hash_algo; + + if (xattr_value) + ima_get_hash_algo(*xattr_value, *xattr_len, &hash.hdr); + + result = ima_calc_file_hash(file, &hash.hdr); if (!result) { - iint->version = i_version; - iint->flags |= IMA_COLLECTED; + int length = sizeof(hash.hdr) + hash.hdr.length; + void *tmpbuf = krealloc(iint->ima_hash, length, + GFP_NOFS); + if (tmpbuf) { + iint->ima_hash = tmpbuf; + memcpy(iint->ima_hash, &hash, length); + iint->version = i_version; + iint->flags |= IMA_COLLECTED; + } else + result = -ENOMEM; } } if (result) @@ -177,7 +242,9 @@ int ima_collect_measurement(struct integrity_iint_cache *iint, * Must be called with iint->mutex held. */ void ima_store_measurement(struct integrity_iint_cache *iint, - struct file *file, const unsigned char *filename) + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len) { const char *op = "add_template_measure"; const char *audit_cause = "ENOMEM"; @@ -189,19 +256,15 @@ void ima_store_measurement(struct integrity_iint_cache *iint, if (iint->flags & IMA_MEASURED) return; - entry = kmalloc(sizeof(*entry), GFP_KERNEL); - if (!entry) { + result = ima_alloc_init_template(iint, file, filename, + xattr_value, xattr_len, &entry); + if (result < 0) { integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename, op, audit_cause, result, 0); return; } - memset(&entry->template, 0, sizeof(entry->template)); - memcpy(entry->template.digest, iint->ima_xattr.digest, IMA_DIGEST_SIZE); - strcpy(entry->template.file_name, - (strlen(filename) > IMA_EVENT_NAME_LEN_MAX) ? - file->f_dentry->d_name.name : filename); - result = ima_store_template(entry, violation, inode); + result = ima_store_template(entry, violation, inode, filename); if (!result || result == -EEXIST) iint->flags |= IMA_MEASURED; if (result < 0) @@ -212,14 +275,16 @@ void ima_audit_measurement(struct integrity_iint_cache *iint, const unsigned char *filename) { struct audit_buffer *ab; - char hash[(IMA_DIGEST_SIZE * 2) + 1]; + char hash[(iint->ima_hash->length * 2) + 1]; + const char *algo_name = hash_algo_name[iint->ima_hash->algo]; + char algo_hash[sizeof(hash) + strlen(algo_name) + 2]; int i; if (iint->flags & IMA_AUDITED) return; - for (i = 0; i < IMA_DIGEST_SIZE; i++) - hex_byte_pack(hash + (i * 2), iint->ima_xattr.digest[i]); + for (i = 0; i < iint->ima_hash->length; i++) + hex_byte_pack(hash + (i * 2), iint->ima_hash->digest[i]); hash[i * 2] = '\0'; ab = audit_log_start(current->audit_context, GFP_KERNEL, @@ -230,7 +295,8 @@ void ima_audit_measurement(struct integrity_iint_cache *iint, audit_log_format(ab, "file="); audit_log_untrustedstring(ab, filename); audit_log_format(ab, " hash="); - audit_log_untrustedstring(ab, hash); + snprintf(algo_hash, sizeof(algo_hash), "%s:%s", algo_name, hash); + audit_log_untrustedstring(ab, algo_hash); audit_log_task_info(ab, current); audit_log_end(ab); diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 2d4becab8918..46353ee517f6 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -15,6 +15,7 @@ #include <linux/magic.h> #include <linux/ima.h> #include <linux/evm.h> +#include <crypto/hash_info.h> #include "ima.h" @@ -43,19 +44,31 @@ int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func) } static int ima_fix_xattr(struct dentry *dentry, - struct integrity_iint_cache *iint) + struct integrity_iint_cache *iint) { - iint->ima_xattr.type = IMA_XATTR_DIGEST; - return __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA, - (u8 *)&iint->ima_xattr, - sizeof(iint->ima_xattr), 0); + int rc, offset; + u8 algo = iint->ima_hash->algo; + + if (algo <= HASH_ALGO_SHA1) { + offset = 1; + iint->ima_hash->xattr.sha1.type = IMA_XATTR_DIGEST; + } else { + offset = 0; + iint->ima_hash->xattr.ng.type = IMA_XATTR_DIGEST_NG; + iint->ima_hash->xattr.ng.algo = algo; + } + rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA, + &iint->ima_hash->xattr.data[offset], + (sizeof(iint->ima_hash->xattr) - offset) + + iint->ima_hash->length, 0); + return rc; } /* Return specific func appraised cached result */ enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, int func) { - switch(func) { + switch (func) { case MMAP_CHECK: return iint->ima_mmap_status; case BPRM_CHECK: @@ -71,7 +84,7 @@ enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, static void ima_set_cache_status(struct integrity_iint_cache *iint, int func, enum integrity_status status) { - switch(func) { + switch (func) { case MMAP_CHECK: iint->ima_mmap_status = status; break; @@ -90,7 +103,7 @@ static void ima_set_cache_status(struct integrity_iint_cache *iint, static void ima_cache_flags(struct integrity_iint_cache *iint, int func) { - switch(func) { + switch (func) { case MMAP_CHECK: iint->flags |= (IMA_MMAP_APPRAISED | IMA_APPRAISED); break; @@ -107,6 +120,50 @@ static void ima_cache_flags(struct integrity_iint_cache *iint, int func) } } +void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_digest_data *hash) +{ + struct signature_v2_hdr *sig; + + if (!xattr_value || xattr_len < 2) + return; + + switch (xattr_value->type) { + case EVM_IMA_XATTR_DIGSIG: + sig = (typeof(sig))xattr_value; + if (sig->version != 2 || xattr_len <= sizeof(*sig)) + return; + hash->algo = sig->hash_algo; + break; + case IMA_XATTR_DIGEST_NG: + hash->algo = xattr_value->digest[0]; + break; + case IMA_XATTR_DIGEST: + /* this is for backward compatibility */ + if (xattr_len == 21) { + unsigned int zero = 0; + if (!memcmp(&xattr_value->digest[16], &zero, 4)) + hash->algo = HASH_ALGO_MD5; + else + hash->algo = HASH_ALGO_SHA1; + } else if (xattr_len == 17) + hash->algo = HASH_ALGO_MD5; + break; + } +} + +int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value) +{ + struct inode *inode = dentry->d_inode; + + if (!inode->i_op->getxattr) + return 0; + + return vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)xattr_value, + 0, GFP_NOFS); +} + /* * ima_appraise_measurement - appraise file measurement * @@ -116,23 +173,22 @@ static void ima_cache_flags(struct integrity_iint_cache *iint, int func) * Return 0 on success, error code otherwise */ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, - struct file *file, const unsigned char *filename) + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len) { struct dentry *dentry = file->f_dentry; struct inode *inode = dentry->d_inode; - struct evm_ima_xattr_data *xattr_value = NULL; enum integrity_status status = INTEGRITY_UNKNOWN; const char *op = "appraise_data"; char *cause = "unknown"; - int rc; + int rc = xattr_len, hash_start = 0; if (!ima_appraise) return 0; if (!inode->i_op->getxattr) return INTEGRITY_UNKNOWN; - rc = vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)&xattr_value, - 0, GFP_NOFS); if (rc <= 0) { if (rc && rc != -ENODATA) goto out; @@ -153,14 +209,25 @@ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, goto out; } switch (xattr_value->type) { + case IMA_XATTR_DIGEST_NG: + /* first byte contains algorithm id */ + hash_start = 1; case IMA_XATTR_DIGEST: if (iint->flags & IMA_DIGSIG_REQUIRED) { cause = "IMA signature required"; status = INTEGRITY_FAIL; break; } - rc = memcmp(xattr_value->digest, iint->ima_xattr.digest, - IMA_DIGEST_SIZE); + if (xattr_len - sizeof(xattr_value->type) - hash_start >= + iint->ima_hash->length) + /* xattr length may be longer. md5 hash in previous + version occupied 20 bytes in xattr, instead of 16 + */ + rc = memcmp(&xattr_value->digest[hash_start], + iint->ima_hash->digest, + iint->ima_hash->length); + else + rc = -EINVAL; if (rc) { cause = "invalid-hash"; status = INTEGRITY_FAIL; @@ -171,9 +238,9 @@ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, case EVM_IMA_XATTR_DIGSIG: iint->flags |= IMA_DIGSIG; rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA, - xattr_value->digest, rc - 1, - iint->ima_xattr.digest, - IMA_DIGEST_SIZE); + (const char *)xattr_value, rc, + iint->ima_hash->digest, + iint->ima_hash->length); if (rc == -EOPNOTSUPP) { status = INTEGRITY_UNKNOWN; } else if (rc) { @@ -203,7 +270,6 @@ out: ima_cache_flags(iint, func); } ima_set_cache_status(iint, func, status); - kfree(xattr_value); return status; } @@ -219,7 +285,7 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file) if (iint->flags & IMA_DIGSIG) return; - rc = ima_collect_measurement(iint, file); + rc = ima_collect_measurement(iint, file, NULL, NULL); if (rc < 0) return; @@ -315,3 +381,14 @@ int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name) } return result; } + +#ifdef CONFIG_IMA_TRUSTED_KEYRING +static int __init init_ima_keyring(void) +{ + int ret; + + ret = integrity_init_keyring(INTEGRITY_KEYRING_IMA); + return 0; +} +late_initcall(init_ima_keyring); +#endif diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index a02e0791cf15..676e0292dfec 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -20,6 +20,7 @@ #include <linux/err.h> #include <linux/slab.h> #include <crypto/hash.h> +#include <crypto/hash_info.h> #include "ima.h" static struct crypto_shash *ima_shash_tfm; @@ -28,31 +29,58 @@ int ima_init_crypto(void) { long rc; - ima_shash_tfm = crypto_alloc_shash(ima_hash, 0, 0); + ima_shash_tfm = crypto_alloc_shash(hash_algo_name[ima_hash_algo], 0, 0); if (IS_ERR(ima_shash_tfm)) { rc = PTR_ERR(ima_shash_tfm); - pr_err("Can not allocate %s (reason: %ld)\n", ima_hash, rc); + pr_err("Can not allocate %s (reason: %ld)\n", + hash_algo_name[ima_hash_algo], rc); return rc; } return 0; } +static struct crypto_shash *ima_alloc_tfm(enum hash_algo algo) +{ + struct crypto_shash *tfm = ima_shash_tfm; + int rc; + + if (algo != ima_hash_algo && algo < HASH_ALGO__LAST) { + tfm = crypto_alloc_shash(hash_algo_name[algo], 0, 0); + if (IS_ERR(tfm)) { + rc = PTR_ERR(tfm); + pr_err("Can not allocate %s (reason: %d)\n", + hash_algo_name[algo], rc); + } + } + return tfm; +} + +static void ima_free_tfm(struct crypto_shash *tfm) +{ + if (tfm != ima_shash_tfm) + crypto_free_shash(tfm); +} + /* * Calculate the MD5/SHA1 file digest */ -int ima_calc_file_hash(struct file *file, char *digest) +static int ima_calc_file_hash_tfm(struct file *file, + struct ima_digest_data *hash, + struct crypto_shash *tfm) { loff_t i_size, offset = 0; char *rbuf; int rc, read = 0; struct { struct shash_desc shash; - char ctx[crypto_shash_descsize(ima_shash_tfm)]; + char ctx[crypto_shash_descsize(tfm)]; } desc; - desc.shash.tfm = ima_shash_tfm; + desc.shash.tfm = tfm; desc.shash.flags = 0; + hash->length = crypto_shash_digestsize(tfm); + rc = crypto_shash_init(&desc.shash); if (rc != 0) return rc; @@ -85,27 +113,83 @@ int ima_calc_file_hash(struct file *file, char *digest) } kfree(rbuf); if (!rc) - rc = crypto_shash_final(&desc.shash, digest); + rc = crypto_shash_final(&desc.shash, hash->digest); if (read) file->f_mode &= ~FMODE_READ; out: return rc; } +int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) +{ + struct crypto_shash *tfm; + int rc; + + tfm = ima_alloc_tfm(hash->algo); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + rc = ima_calc_file_hash_tfm(file, hash, tfm); + + ima_free_tfm(tfm); + + return rc; +} + /* - * Calculate the hash of a given buffer + * Calculate the hash of template data */ -int ima_calc_buffer_hash(const void *data, int len, char *digest) +static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data, + int num_fields, + struct ima_digest_data *hash, + struct crypto_shash *tfm) { struct { struct shash_desc shash; - char ctx[crypto_shash_descsize(ima_shash_tfm)]; + char ctx[crypto_shash_descsize(tfm)]; } desc; + int rc, i; - desc.shash.tfm = ima_shash_tfm; + desc.shash.tfm = tfm; desc.shash.flags = 0; - return crypto_shash_digest(&desc.shash, data, len, digest); + hash->length = crypto_shash_digestsize(tfm); + + rc = crypto_shash_init(&desc.shash); + if (rc != 0) + return rc; + + for (i = 0; i < num_fields; i++) { + rc = crypto_shash_update(&desc.shash, + (const u8 *) &field_data[i].len, + sizeof(field_data[i].len)); + rc = crypto_shash_update(&desc.shash, field_data[i].data, + field_data[i].len); + if (rc) + break; + } + + if (!rc) + rc = crypto_shash_final(&desc.shash, hash->digest); + + return rc; +} + +int ima_calc_field_array_hash(struct ima_field_data *field_data, int num_fields, + struct ima_digest_data *hash) +{ + struct crypto_shash *tfm; + int rc; + + tfm = ima_alloc_tfm(hash->algo); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + rc = ima_calc_field_array_hash_tfm(field_data, num_fields, hash, tfm); + + ima_free_tfm(tfm); + + return rc; } static void __init ima_pcrread(int idx, u8 *pcr) @@ -120,16 +204,17 @@ static void __init ima_pcrread(int idx, u8 *pcr) /* * Calculate the boot aggregate hash */ -int __init ima_calc_boot_aggregate(char *digest) +static int __init ima_calc_boot_aggregate_tfm(char *digest, + struct crypto_shash *tfm) { - u8 pcr_i[IMA_DIGEST_SIZE]; + u8 pcr_i[TPM_DIGEST_SIZE]; int rc, i; struct { struct shash_desc shash; - char ctx[crypto_shash_descsize(ima_shash_tfm)]; + char ctx[crypto_shash_descsize(tfm)]; } desc; - desc.shash.tfm = ima_shash_tfm; + desc.shash.tfm = tfm; desc.shash.flags = 0; rc = crypto_shash_init(&desc.shash); @@ -140,9 +225,26 @@ int __init ima_calc_boot_aggregate(char *digest) for (i = TPM_PCR0; i < TPM_PCR8; i++) { ima_pcrread(i, pcr_i); /* now accumulate with current aggregate */ - rc = crypto_shash_update(&desc.shash, pcr_i, IMA_DIGEST_SIZE); + rc = crypto_shash_update(&desc.shash, pcr_i, TPM_DIGEST_SIZE); } if (!rc) crypto_shash_final(&desc.shash, digest); return rc; } + +int __init ima_calc_boot_aggregate(struct ima_digest_data *hash) +{ + struct crypto_shash *tfm; + int rc; + + tfm = ima_alloc_tfm(hash->algo); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + hash->length = crypto_shash_digestsize(tfm); + rc = ima_calc_boot_aggregate_tfm(hash->digest, tfm); + + ima_free_tfm(tfm); + + return rc; +} diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 38477c9c3415..d47a7c86a21d 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -88,8 +88,7 @@ static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos) * against concurrent list-extension */ rcu_read_lock(); - qe = list_entry_rcu(qe->later.next, - struct ima_queue_entry, later); + qe = list_entry_rcu(qe->later.next, struct ima_queue_entry, later); rcu_read_unlock(); (*pos)++; @@ -100,7 +99,7 @@ static void ima_measurements_stop(struct seq_file *m, void *v) { } -static void ima_putc(struct seq_file *m, void *data, int datalen) +void ima_putc(struct seq_file *m, void *data, int datalen) { while (datalen--) seq_putc(m, *(char *)data++); @@ -111,6 +110,7 @@ static void ima_putc(struct seq_file *m, void *data, int datalen) * char[20]=template digest * 32bit-le=template name size * char[n]=template name + * [eventdata length] * eventdata[n]=template specific data */ static int ima_measurements_show(struct seq_file *m, void *v) @@ -120,6 +120,7 @@ static int ima_measurements_show(struct seq_file *m, void *v) struct ima_template_entry *e; int namelen; u32 pcr = CONFIG_IMA_MEASURE_PCR_IDX; + int i; /* get entry */ e = qe->entry; @@ -134,18 +135,25 @@ static int ima_measurements_show(struct seq_file *m, void *v) ima_putc(m, &pcr, sizeof pcr); /* 2nd: template digest */ - ima_putc(m, e->digest, IMA_DIGEST_SIZE); + ima_putc(m, e->digest, TPM_DIGEST_SIZE); /* 3rd: template name size */ - namelen = strlen(e->template_name); + namelen = strlen(e->template_desc->name); ima_putc(m, &namelen, sizeof namelen); /* 4th: template name */ - ima_putc(m, (void *)e->template_name, namelen); + ima_putc(m, e->template_desc->name, namelen); + + /* 5th: template length (except for 'ima' template) */ + if (strcmp(e->template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0) + ima_putc(m, &e->template_data_len, + sizeof(e->template_data_len)); - /* 5th: template specific data */ - ima_template_show(m, (struct ima_template_data *)&e->template, - IMA_SHOW_BINARY); + /* 6th: template specific data */ + for (i = 0; i < e->template_desc->num_fields; i++) { + e->template_desc->fields[i]->field_show(m, IMA_SHOW_BINARY, + &e->template_data[i]); + } return 0; } @@ -168,41 +176,21 @@ static const struct file_operations ima_measurements_ops = { .release = seq_release, }; -static void ima_print_digest(struct seq_file *m, u8 *digest) +void ima_print_digest(struct seq_file *m, u8 *digest, int size) { int i; - for (i = 0; i < IMA_DIGEST_SIZE; i++) + for (i = 0; i < size; i++) seq_printf(m, "%02x", *(digest + i)); } -void ima_template_show(struct seq_file *m, void *e, enum ima_show_type show) -{ - struct ima_template_data *entry = e; - int namelen; - - switch (show) { - case IMA_SHOW_ASCII: - ima_print_digest(m, entry->digest); - seq_printf(m, " %s\n", entry->file_name); - break; - case IMA_SHOW_BINARY: - ima_putc(m, entry->digest, IMA_DIGEST_SIZE); - - namelen = strlen(entry->file_name); - ima_putc(m, &namelen, sizeof namelen); - ima_putc(m, entry->file_name, namelen); - default: - break; - } -} - /* print in ascii */ static int ima_ascii_measurements_show(struct seq_file *m, void *v) { /* the list never shrinks, so we don't need a lock here */ struct ima_queue_entry *qe = v; struct ima_template_entry *e; + int i; /* get entry */ e = qe->entry; @@ -213,14 +201,21 @@ static int ima_ascii_measurements_show(struct seq_file *m, void *v) seq_printf(m, "%2d ", CONFIG_IMA_MEASURE_PCR_IDX); /* 2nd: SHA1 template hash */ - ima_print_digest(m, e->digest); + ima_print_digest(m, e->digest, TPM_DIGEST_SIZE); /* 3th: template name */ - seq_printf(m, " %s ", e->template_name); + seq_printf(m, " %s", e->template_desc->name); /* 4th: template specific data */ - ima_template_show(m, (struct ima_template_data *)&e->template, - IMA_SHOW_ASCII); + for (i = 0; i < e->template_desc->num_fields; i++) { + seq_puts(m, " "); + if (e->template_data[i].len == 0) + continue; + + e->template_desc->fields[i]->field_show(m, IMA_SHOW_ASCII, + &e->template_data[i]); + } + seq_puts(m, "\n"); return 0; } diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c index 162ea723db3d..15f34bd40abe 100644 --- a/security/integrity/ima/ima_init.c +++ b/security/integrity/ima/ima_init.c @@ -18,6 +18,7 @@ #include <linux/scatterlist.h> #include <linux/slab.h> #include <linux/err.h> +#include <crypto/hash_info.h> #include "ima.h" /* name for boot aggregate entry */ @@ -42,28 +43,38 @@ int ima_used_chip; static void __init ima_add_boot_aggregate(void) { struct ima_template_entry *entry; + struct integrity_iint_cache tmp_iint, *iint = &tmp_iint; const char *op = "add_boot_aggregate"; const char *audit_cause = "ENOMEM"; int result = -ENOMEM; - int violation = 1; + int violation = 0; + struct { + struct ima_digest_data hdr; + char digest[TPM_DIGEST_SIZE]; + } hash; - entry = kmalloc(sizeof(*entry), GFP_KERNEL); - if (!entry) - goto err_out; + memset(iint, 0, sizeof(*iint)); + memset(&hash, 0, sizeof(hash)); + iint->ima_hash = &hash.hdr; + iint->ima_hash->algo = HASH_ALGO_SHA1; + iint->ima_hash->length = SHA1_DIGEST_SIZE; - memset(&entry->template, 0, sizeof(entry->template)); - strncpy(entry->template.file_name, boot_aggregate_name, - IMA_EVENT_NAME_LEN_MAX); if (ima_used_chip) { - violation = 0; - result = ima_calc_boot_aggregate(entry->template.digest); + result = ima_calc_boot_aggregate(&hash.hdr); if (result < 0) { audit_cause = "hashing_error"; kfree(entry); goto err_out; } } - result = ima_store_template(entry, violation, NULL); + + result = ima_alloc_init_template(iint, NULL, boot_aggregate_name, + NULL, 0, &entry); + if (result < 0) + return; + + result = ima_store_template(entry, violation, NULL, + boot_aggregate_name); if (result < 0) kfree(entry); return; @@ -74,7 +85,7 @@ err_out: int __init ima_init(void) { - u8 pcr_i[IMA_DIGEST_SIZE]; + u8 pcr_i[TPM_DIGEST_SIZE]; int rc; ima_used_chip = 0; @@ -88,6 +99,10 @@ int __init ima_init(void) rc = ima_init_crypto(); if (rc) return rc; + rc = ima_init_template(); + if (rc != 0) + return rc; + ima_add_boot_aggregate(); /* boot aggregate must be first entry */ ima_init_policy(); diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index e9508d5bbfcf..149ee1119f87 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -24,6 +24,7 @@ #include <linux/slab.h> #include <linux/xattr.h> #include <linux/ima.h> +#include <crypto/hash_info.h> #include "ima.h" @@ -35,11 +36,33 @@ int ima_appraise = IMA_APPRAISE_ENFORCE; int ima_appraise; #endif -char *ima_hash = "sha1"; +int ima_hash_algo = HASH_ALGO_SHA1; +static int hash_setup_done; + static int __init hash_setup(char *str) { - if (strncmp(str, "md5", 3) == 0) - ima_hash = "md5"; + struct ima_template_desc *template_desc = ima_template_desc_current(); + int i; + + if (hash_setup_done) + return 1; + + if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) { + if (strncmp(str, "sha1", 4) == 0) + ima_hash_algo = HASH_ALGO_SHA1; + else if (strncmp(str, "md5", 3) == 0) + ima_hash_algo = HASH_ALGO_MD5; + goto out; + } + + for (i = 0; i < HASH_ALGO__LAST; i++) { + if (strcmp(str, hash_algo_name[i]) == 0) { + ima_hash_algo = i; + break; + } + } +out: + hash_setup_done = 1; return 1; } __setup("ima_hash=", hash_setup); @@ -92,10 +115,9 @@ out: pathname = dentry->d_name.name; if (send_tomtou) - ima_add_violation(inode, pathname, - "invalid_pcr", "ToMToU"); + ima_add_violation(file, pathname, "invalid_pcr", "ToMToU"); if (send_writers) - ima_add_violation(inode, pathname, + ima_add_violation(file, pathname, "invalid_pcr", "open_writers"); kfree(pathbuf); } @@ -144,9 +166,12 @@ static int process_measurement(struct file *file, const char *filename, { struct inode *inode = file_inode(file); struct integrity_iint_cache *iint; + struct ima_template_desc *template_desc = ima_template_desc_current(); char *pathbuf = NULL; const char *pathname = NULL; int rc = -ENOMEM, action, must_appraise, _func; + struct evm_ima_xattr_data *xattr_value = NULL, **xattr_ptr = NULL; + int xattr_len = 0; if (!ima_initialized || !S_ISREG(inode->i_mode)) return 0; @@ -185,7 +210,13 @@ static int process_measurement(struct file *file, const char *filename, goto out_digsig; } - rc = ima_collect_measurement(iint, file); + if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) { + if (action & IMA_APPRAISE_SUBMASK) + xattr_ptr = &xattr_value; + } else + xattr_ptr = &xattr_value; + + rc = ima_collect_measurement(iint, file, xattr_ptr, &xattr_len); if (rc != 0) goto out_digsig; @@ -194,9 +225,11 @@ static int process_measurement(struct file *file, const char *filename, pathname = (const char *)file->f_dentry->d_name.name; if (action & IMA_MEASURE) - ima_store_measurement(iint, file, pathname); + ima_store_measurement(iint, file, pathname, + xattr_value, xattr_len); if (action & IMA_APPRAISE_SUBMASK) - rc = ima_appraise_measurement(_func, iint, file, pathname); + rc = ima_appraise_measurement(_func, iint, file, pathname, + xattr_value, xattr_len); if (action & IMA_AUDIT) ima_audit_measurement(iint, pathname); kfree(pathbuf); @@ -205,6 +238,7 @@ out_digsig: rc = -EACCES; out: mutex_unlock(&inode->i_mutex); + kfree(xattr_value); if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE)) return -EACCES; return 0; @@ -244,9 +278,9 @@ int ima_file_mmap(struct file *file, unsigned long prot) int ima_bprm_check(struct linux_binprm *bprm) { return process_measurement(bprm->file, - (strcmp(bprm->filename, bprm->interp) == 0) ? - bprm->filename : bprm->interp, - MAY_EXEC, BPRM_CHECK); + (strcmp(bprm->filename, bprm->interp) == 0) ? + bprm->filename : bprm->interp, + MAY_EXEC, BPRM_CHECK); } /** @@ -263,8 +297,8 @@ int ima_file_check(struct file *file, int mask) { ima_rdwr_violation_check(file); return process_measurement(file, NULL, - mask & (MAY_READ | MAY_WRITE | MAY_EXEC), - FILE_CHECK); + mask & (MAY_READ | MAY_WRITE | MAY_EXEC), + FILE_CHECK); } EXPORT_SYMBOL_GPL(ima_file_check); @@ -294,6 +328,7 @@ static int __init init_ima(void) { int error; + hash_setup(CONFIG_IMA_DEFAULT_HASH); error = ima_init(); if (!error) ima_initialized = 1; diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 399433ad614e..a9c3d3cd1990 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -73,7 +73,6 @@ static struct ima_rule_entry default_rules[] = { {.action = DONT_MEASURE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC}, - {.action = DONT_MEASURE,.fsmagic = RAMFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = DEVPTS_SUPER_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = BINFMTFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC}, diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c index ff63fe00c195..d85e99761f4f 100644 --- a/security/integrity/ima/ima_queue.c +++ b/security/integrity/ima/ima_queue.c @@ -50,7 +50,7 @@ static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value) key = ima_hash_key(digest_value); rcu_read_lock(); hlist_for_each_entry_rcu(qe, &ima_htable.queue[key], hnext) { - rc = memcmp(qe->entry->digest, digest_value, IMA_DIGEST_SIZE); + rc = memcmp(qe->entry->digest, digest_value, TPM_DIGEST_SIZE); if (rc == 0) { ret = qe; break; @@ -104,9 +104,10 @@ static int ima_pcr_extend(const u8 *hash) * and extend the pcr. */ int ima_add_template_entry(struct ima_template_entry *entry, int violation, - const char *op, struct inode *inode) + const char *op, struct inode *inode, + const unsigned char *filename) { - u8 digest[IMA_DIGEST_SIZE]; + u8 digest[TPM_DIGEST_SIZE]; const char *audit_cause = "hash_added"; char tpm_audit_cause[AUDIT_CAUSE_LEN_MAX]; int audit_info = 1; @@ -141,8 +142,7 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation, } out: mutex_unlock(&ima_extend_list_mutex); - integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, - entry->template.file_name, + integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode, filename, op, audit_cause, result, audit_info); return result; } diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c new file mode 100644 index 000000000000..4e5da990630b --- /dev/null +++ b/security/integrity/ima/ima_template.c @@ -0,0 +1,178 @@ +/* + * Copyright (C) 2013 Politecnico di Torino, Italy + * TORSEC group -- http://security.polito.it + * + * Author: Roberto Sassu <roberto.sassu@polito.it> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * File: ima_template.c + * Helpers to manage template descriptors. + */ +#include <crypto/hash_info.h> + +#include "ima.h" +#include "ima_template_lib.h" + +static struct ima_template_desc defined_templates[] = { + {.name = IMA_TEMPLATE_IMA_NAME, .fmt = IMA_TEMPLATE_IMA_FMT}, + {.name = "ima-ng",.fmt = "d-ng|n-ng"}, + {.name = "ima-sig",.fmt = "d-ng|n-ng|sig"}, +}; + +static struct ima_template_field supported_fields[] = { + {.field_id = "d",.field_init = ima_eventdigest_init, + .field_show = ima_show_template_digest}, + {.field_id = "n",.field_init = ima_eventname_init, + .field_show = ima_show_template_string}, + {.field_id = "d-ng",.field_init = ima_eventdigest_ng_init, + .field_show = ima_show_template_digest_ng}, + {.field_id = "n-ng",.field_init = ima_eventname_ng_init, + .field_show = ima_show_template_string}, + {.field_id = "sig",.field_init = ima_eventsig_init, + .field_show = ima_show_template_sig}, +}; + +static struct ima_template_desc *ima_template; +static struct ima_template_desc *lookup_template_desc(const char *name); + +static int __init ima_template_setup(char *str) +{ + struct ima_template_desc *template_desc; + int template_len = strlen(str); + + /* + * Verify that a template with the supplied name exists. + * If not, use CONFIG_IMA_DEFAULT_TEMPLATE. + */ + template_desc = lookup_template_desc(str); + if (!template_desc) + return 1; + + /* + * Verify whether the current hash algorithm is supported + * by the 'ima' template. + */ + if (template_len == 3 && strcmp(str, IMA_TEMPLATE_IMA_NAME) == 0 && + ima_hash_algo != HASH_ALGO_SHA1 && ima_hash_algo != HASH_ALGO_MD5) { + pr_err("IMA: template does not support hash alg\n"); + return 1; + } + + ima_template = template_desc; + return 1; +} +__setup("ima_template=", ima_template_setup); + +static struct ima_template_desc *lookup_template_desc(const char *name) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(defined_templates); i++) { + if (strcmp(defined_templates[i].name, name) == 0) + return defined_templates + i; + } + + return NULL; +} + +static struct ima_template_field *lookup_template_field(const char *field_id) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(supported_fields); i++) + if (strncmp(supported_fields[i].field_id, field_id, + IMA_TEMPLATE_FIELD_ID_MAX_LEN) == 0) + return &supported_fields[i]; + return NULL; +} + +static int template_fmt_size(char *template_fmt) +{ + char c; + int template_fmt_len = strlen(template_fmt); + int i = 0, j = 0; + + while (i < template_fmt_len) { + c = template_fmt[i]; + if (c == '|') + j++; + i++; + } + + return j + 1; +} + +static int template_desc_init_fields(char *template_fmt, + struct ima_template_field ***fields, + int *num_fields) +{ + char *c, *template_fmt_ptr = template_fmt; + int template_num_fields = template_fmt_size(template_fmt); + int i, result = 0; + + if (template_num_fields > IMA_TEMPLATE_NUM_FIELDS_MAX) + return -EINVAL; + + *fields = kzalloc(template_num_fields * sizeof(*fields), GFP_KERNEL); + if (*fields == NULL) { + result = -ENOMEM; + goto out; + } + for (i = 0; (c = strsep(&template_fmt_ptr, "|")) != NULL && + i < template_num_fields; i++) { + struct ima_template_field *f = lookup_template_field(c); + + if (!f) { + result = -ENOENT; + goto out; + } + (*fields)[i] = f; + } + *num_fields = i; + return 0; +out: + kfree(*fields); + *fields = NULL; + return result; +} + +static int init_defined_templates(void) +{ + int i = 0; + int result = 0; + + /* Init defined templates. */ + for (i = 0; i < ARRAY_SIZE(defined_templates); i++) { + struct ima_template_desc *template = &defined_templates[i]; + + result = template_desc_init_fields(template->fmt, + &(template->fields), + &(template->num_fields)); + if (result < 0) + return result; + } + return result; +} + +struct ima_template_desc *ima_template_desc_current(void) +{ + if (!ima_template) + ima_template = + lookup_template_desc(CONFIG_IMA_DEFAULT_TEMPLATE); + return ima_template; +} + +int ima_init_template(void) +{ + int result; + + result = init_defined_templates(); + if (result < 0) + return result; + + return 0; +} diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c new file mode 100644 index 000000000000..6d66ad6ed265 --- /dev/null +++ b/security/integrity/ima/ima_template_lib.c @@ -0,0 +1,347 @@ +/* + * Copyright (C) 2013 Politecnico di Torino, Italy + * TORSEC group -- http://security.polito.it + * + * Author: Roberto Sassu <roberto.sassu@polito.it> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * File: ima_template_lib.c + * Library of supported template fields. + */ +#include <crypto/hash_info.h> + +#include "ima_template_lib.h" + +static bool ima_template_hash_algo_allowed(u8 algo) +{ + if (algo == HASH_ALGO_SHA1 || algo == HASH_ALGO_MD5) + return true; + + return false; +} + +enum data_formats { + DATA_FMT_DIGEST = 0, + DATA_FMT_DIGEST_WITH_ALGO, + DATA_FMT_EVENT_NAME, + DATA_FMT_STRING, + DATA_FMT_HEX +}; + +static int ima_write_template_field_data(const void *data, const u32 datalen, + enum data_formats datafmt, + struct ima_field_data *field_data) +{ + u8 *buf, *buf_ptr; + u32 buflen; + + switch (datafmt) { + case DATA_FMT_EVENT_NAME: + buflen = IMA_EVENT_NAME_LEN_MAX + 1; + break; + case DATA_FMT_STRING: + buflen = datalen + 1; + break; + default: + buflen = datalen; + } + + buf = kzalloc(buflen, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + memcpy(buf, data, datalen); + + /* + * Replace all space characters with underscore for event names and + * strings. This avoid that, during the parsing of a measurements list, + * filenames with spaces or that end with the suffix ' (deleted)' are + * split into multiple template fields (the space is the delimitator + * character for measurements lists in ASCII format). + */ + if (datafmt == DATA_FMT_EVENT_NAME || datafmt == DATA_FMT_STRING) { + for (buf_ptr = buf; buf_ptr - buf < datalen; buf_ptr++) + if (*buf_ptr == ' ') + *buf_ptr = '_'; + } + + field_data->data = buf; + field_data->len = buflen; + return 0; +} + +static void ima_show_template_data_ascii(struct seq_file *m, + enum ima_show_type show, + enum data_formats datafmt, + struct ima_field_data *field_data) +{ + u8 *buf_ptr = field_data->data, buflen = field_data->len; + + switch (datafmt) { + case DATA_FMT_DIGEST_WITH_ALGO: + buf_ptr = strnchr(field_data->data, buflen, ':'); + if (buf_ptr != field_data->data) + seq_printf(m, "%s", field_data->data); + + /* skip ':' and '\0' */ + buf_ptr += 2; + buflen -= buf_ptr - field_data->data; + case DATA_FMT_DIGEST: + case DATA_FMT_HEX: + if (!buflen) + break; + ima_print_digest(m, buf_ptr, buflen); + break; + case DATA_FMT_STRING: + seq_printf(m, "%s", buf_ptr); + break; + default: + break; + } +} + +static void ima_show_template_data_binary(struct seq_file *m, + enum ima_show_type show, + enum data_formats datafmt, + struct ima_field_data *field_data) +{ + ima_putc(m, &field_data->len, sizeof(u32)); + if (!field_data->len) + return; + ima_putc(m, field_data->data, field_data->len); +} + +static void ima_show_template_field_data(struct seq_file *m, + enum ima_show_type show, + enum data_formats datafmt, + struct ima_field_data *field_data) +{ + switch (show) { + case IMA_SHOW_ASCII: + ima_show_template_data_ascii(m, show, datafmt, field_data); + break; + case IMA_SHOW_BINARY: + ima_show_template_data_binary(m, show, datafmt, field_data); + break; + default: + break; + } +} + +void ima_show_template_digest(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data) +{ + ima_show_template_field_data(m, show, DATA_FMT_DIGEST, field_data); +} + +void ima_show_template_digest_ng(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data) +{ + ima_show_template_field_data(m, show, DATA_FMT_DIGEST_WITH_ALGO, + field_data); +} + +void ima_show_template_string(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data) +{ + ima_show_template_field_data(m, show, DATA_FMT_STRING, field_data); +} + +void ima_show_template_sig(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data) +{ + ima_show_template_field_data(m, show, DATA_FMT_HEX, field_data); +} + +static int ima_eventdigest_init_common(u8 *digest, u32 digestsize, u8 hash_algo, + struct ima_field_data *field_data, + bool size_limit) +{ + /* + * 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 + * SHA1 or MD5 + */ + u8 buffer[CRYPTO_MAX_ALG_NAME + 2 + IMA_MAX_DIGEST_SIZE] = { 0 }; + enum data_formats fmt = DATA_FMT_DIGEST; + u32 offset = 0; + + if (!size_limit) { + fmt = DATA_FMT_DIGEST_WITH_ALGO; + if (hash_algo < HASH_ALGO__LAST) + offset += snprintf(buffer, CRYPTO_MAX_ALG_NAME + 1, + "%s", hash_algo_name[hash_algo]); + buffer[offset] = ':'; + offset += 2; + } + + if (digest) + memcpy(buffer + offset, digest, digestsize); + else + /* + * If digest is NULL, the event being recorded is a violation. + * Make room for the digest by increasing the offset of + * IMA_DIGEST_SIZE. + */ + offset += IMA_DIGEST_SIZE; + + return ima_write_template_field_data(buffer, offset + digestsize, + fmt, field_data); +} + +/* + * This function writes the digest of an event (with size limit). + */ +int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_field_data *field_data) +{ + struct { + struct ima_digest_data hdr; + char digest[IMA_MAX_DIGEST_SIZE]; + } hash; + u8 *cur_digest = NULL; + u32 cur_digestsize = 0; + struct inode *inode; + int result; + + memset(&hash, 0, sizeof(hash)); + + if (!iint) /* recording a violation. */ + goto out; + + if (ima_template_hash_algo_allowed(iint->ima_hash->algo)) { + cur_digest = iint->ima_hash->digest; + cur_digestsize = iint->ima_hash->length; + goto out; + } + + if (!file) /* missing info to re-calculate the digest */ + return -EINVAL; + + inode = file_inode(file); + hash.hdr.algo = ima_template_hash_algo_allowed(ima_hash_algo) ? + ima_hash_algo : HASH_ALGO_SHA1; + result = ima_calc_file_hash(file, &hash.hdr); + if (result) { + integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, + filename, "collect_data", + "failed", result, 0); + return result; + } + cur_digest = hash.hdr.digest; + cur_digestsize = hash.hdr.length; +out: + return ima_eventdigest_init_common(cur_digest, cur_digestsize, -1, + field_data, true); +} + +/* + * This function writes the digest of an event (without size limit). + */ +int ima_eventdigest_ng_init(struct integrity_iint_cache *iint, + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, struct ima_field_data *field_data) +{ + u8 *cur_digest = NULL, hash_algo = HASH_ALGO__LAST; + u32 cur_digestsize = 0; + + /* If iint is NULL, we are recording a violation. */ + if (!iint) + goto out; + + cur_digest = iint->ima_hash->digest; + cur_digestsize = iint->ima_hash->length; + + hash_algo = iint->ima_hash->algo; +out: + return ima_eventdigest_init_common(cur_digest, cur_digestsize, + hash_algo, field_data, false); +} + +static int ima_eventname_init_common(struct integrity_iint_cache *iint, + struct file *file, + const unsigned char *filename, + struct ima_field_data *field_data, + bool size_limit) +{ + const char *cur_filename = NULL; + u32 cur_filename_len = 0; + enum data_formats fmt = size_limit ? + DATA_FMT_EVENT_NAME : DATA_FMT_STRING; + + BUG_ON(filename == NULL && file == NULL); + + if (filename) { + cur_filename = filename; + cur_filename_len = strlen(filename); + + if (!size_limit || cur_filename_len <= IMA_EVENT_NAME_LEN_MAX) + goto out; + } + + if (file) { + cur_filename = file->f_dentry->d_name.name; + cur_filename_len = strlen(cur_filename); + } else + /* + * Truncate filename if the latter is too long and + * the file descriptor is not available. + */ + cur_filename_len = IMA_EVENT_NAME_LEN_MAX; +out: + return ima_write_template_field_data(cur_filename, cur_filename_len, + fmt, field_data); +} + +/* + * This function writes the name of an event (with size limit). + */ +int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_field_data *field_data) +{ + return ima_eventname_init_common(iint, file, filename, + field_data, true); +} + +/* + * This function writes the name of an event (without size limit). + */ +int ima_eventname_ng_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_field_data *field_data) +{ + return ima_eventname_init_common(iint, file, filename, + field_data, false); +} + +/* + * ima_eventsig_init - include the file signature as part of the template data + */ +int ima_eventsig_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_field_data *field_data) +{ + enum data_formats fmt = DATA_FMT_HEX; + int rc = 0; + + if ((!xattr_value) || (xattr_value->type != EVM_IMA_XATTR_DIGSIG)) + goto out; + + rc = ima_write_template_field_data(xattr_value, xattr_len, fmt, + field_data); +out: + return rc; +} diff --git a/security/integrity/ima/ima_template_lib.h b/security/integrity/ima/ima_template_lib.h new file mode 100644 index 000000000000..63f6b52cb1c2 --- /dev/null +++ b/security/integrity/ima/ima_template_lib.h @@ -0,0 +1,49 @@ +/* + * Copyright (C) 2013 Politecnico di Torino, Italy + * TORSEC group -- http://security.polito.it + * + * Author: Roberto Sassu <roberto.sassu@polito.it> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * File: ima_template_lib.h + * Header for the library of supported template fields. + */ +#ifndef __LINUX_IMA_TEMPLATE_LIB_H +#define __LINUX_IMA_TEMPLATE_LIB_H + +#include <linux/seq_file.h> +#include "ima.h" + +void ima_show_template_digest(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); +void ima_show_template_digest_ng(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); +void ima_show_template_string(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); +void ima_show_template_sig(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); +int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_field_data *field_data); +int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_field_data *field_data); +int ima_eventdigest_ng_init(struct integrity_iint_cache *iint, + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, struct ima_field_data *field_data); +int ima_eventname_ng_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_field_data *field_data); +int ima_eventsig_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_field_data *field_data); +#endif /* __LINUX_IMA_TEMPLATE_LIB_H */ diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index c42fb7a70dee..b9e7c133734a 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -54,25 +54,57 @@ enum evm_ima_xattr_type { IMA_XATTR_DIGEST = 0x01, EVM_XATTR_HMAC, EVM_IMA_XATTR_DIGSIG, + IMA_XATTR_DIGEST_NG, }; struct evm_ima_xattr_data { u8 type; u8 digest[SHA1_DIGEST_SIZE]; -} __attribute__((packed)); +} __packed; + +#define IMA_MAX_DIGEST_SIZE 64 + +struct ima_digest_data { + u8 algo; + u8 length; + union { + struct { + u8 unused; + u8 type; + } sha1; + struct { + u8 type; + u8 algo; + } ng; + u8 data[2]; + } xattr; + u8 digest[0]; +} __packed; + +/* + * signature format v2 - for using with asymmetric keys + */ +struct signature_v2_hdr { + uint8_t type; /* xattr type */ + uint8_t version; /* signature format version */ + uint8_t hash_algo; /* Digest algorithm [enum pkey_hash_algo] */ + uint32_t keyid; /* IMA key identifier - not X509/PGP specific */ + uint16_t sig_size; /* signature size */ + uint8_t sig[0]; /* signature payload */ +} __packed; /* integrity data associated with an inode */ struct integrity_iint_cache { - struct rb_node rb_node; /* rooted in integrity_iint_tree */ + struct rb_node rb_node; /* rooted in integrity_iint_tree */ struct inode *inode; /* back pointer to inode in question */ u64 version; /* track inode changes */ unsigned long flags; - struct evm_ima_xattr_data ima_xattr; enum integrity_status ima_file_status:4; enum integrity_status ima_mmap_status:4; enum integrity_status ima_bprm_status:4; enum integrity_status ima_module_status:4; enum integrity_status evm_status:4; + struct ima_digest_data *ima_hash; }; /* rbtree tree calls to lookup, insert, delete @@ -89,7 +121,7 @@ struct integrity_iint_cache *integrity_iint_find(struct inode *inode); #ifdef CONFIG_INTEGRITY_SIGNATURE int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, - const char *digest, int digestlen); + const char *digest, int digestlen); #else @@ -105,12 +137,19 @@ static inline int integrity_digsig_verify(const unsigned int id, #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS int asymmetric_verify(struct key *keyring, const char *sig, int siglen, const char *data, int datalen); + +int integrity_init_keyring(const unsigned int id); #else static inline int asymmetric_verify(struct key *keyring, const char *sig, int siglen, const char *data, int datalen) { return -EOPNOTSUPP; } + +static int integrity_init_keyring(const unsigned int id) +{ + return 0; +} #endif #ifdef CONFIG_INTEGRITY_AUDIT |