summaryrefslogtreecommitdiff
path: root/security/integrity/evm/evm_crypto.c
diff options
context:
space:
mode:
Diffstat (limited to 'security/integrity/evm/evm_crypto.c')
-rw-r--r--security/integrity/evm/evm_crypto.c76
1 files changed, 53 insertions, 23 deletions
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index 8738deff26fa..49a464f5595b 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -26,44 +26,56 @@ static unsigned char evmkey[MAX_KEY_SIZE];
static int evmkey_len = MAX_KEY_SIZE;
struct crypto_shash *hmac_tfm;
+struct crypto_shash *hash_tfm;
static DEFINE_MUTEX(mutex);
-static struct shash_desc *init_desc(void)
+static struct shash_desc *init_desc(char type)
{
- int rc;
+ long rc;
+ char *algo;
+ struct crypto_shash **tfm;
struct shash_desc *desc;
- if (hmac_tfm == NULL) {
+ if (type == EVM_XATTR_HMAC) {
+ tfm = &hmac_tfm;
+ algo = evm_hmac;
+ } else {
+ tfm = &hash_tfm;
+ algo = evm_hash;
+ }
+
+ if (*tfm == NULL) {
mutex_lock(&mutex);
- if (hmac_tfm)
+ if (*tfm)
goto out;
- hmac_tfm = crypto_alloc_shash(evm_hmac, 0, CRYPTO_ALG_ASYNC);
- if (IS_ERR(hmac_tfm)) {
- pr_err("Can not allocate %s (reason: %ld)\n",
- evm_hmac, PTR_ERR(hmac_tfm));
- rc = PTR_ERR(hmac_tfm);
- hmac_tfm = NULL;
+ *tfm = crypto_alloc_shash(algo, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(*tfm)) {
+ rc = PTR_ERR(*tfm);
+ pr_err("Can not allocate %s (reason: %ld)\n", algo, rc);
+ *tfm = NULL;
mutex_unlock(&mutex);
return ERR_PTR(rc);
}
- rc = crypto_shash_setkey(hmac_tfm, evmkey, evmkey_len);
- if (rc) {
- crypto_free_shash(hmac_tfm);
- hmac_tfm = NULL;
- mutex_unlock(&mutex);
- return ERR_PTR(rc);
+ if (type == EVM_XATTR_HMAC) {
+ rc = crypto_shash_setkey(*tfm, evmkey, evmkey_len);
+ if (rc) {
+ crypto_free_shash(*tfm);
+ *tfm = NULL;
+ mutex_unlock(&mutex);
+ return ERR_PTR(rc);
+ }
}
out:
mutex_unlock(&mutex);
}
- desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac_tfm),
+ desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(*tfm),
GFP_KERNEL);
if (!desc)
return ERR_PTR(-ENOMEM);
- desc->tfm = hmac_tfm;
+ desc->tfm = *tfm;
desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
rc = crypto_shash_init(desc);
@@ -108,9 +120,11 @@ static void hmac_add_misc(struct shash_desc *desc, struct inode *inode,
* the hmac using the requested xattr value. Don't alloc/free memory for
* each xattr, but attempt to re-use the previously allocated memory.
*/
-int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
- const char *req_xattr_value, size_t req_xattr_value_len,
- char *digest)
+static int evm_calc_hmac_or_hash(struct dentry *dentry,
+ const char *req_xattr_name,
+ const char *req_xattr_value,
+ size_t req_xattr_value_len,
+ char type, char *digest)
{
struct inode *inode = dentry->d_inode;
struct shash_desc *desc;
@@ -122,7 +136,7 @@ int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
if (!inode->i_op || !inode->i_op->getxattr)
return -EOPNOTSUPP;
- desc = init_desc();
+ desc = init_desc(type);
if (IS_ERR(desc))
return PTR_ERR(desc);
@@ -156,6 +170,22 @@ out:
return error;
}
+int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
+ const char *req_xattr_value, size_t req_xattr_value_len,
+ char *digest)
+{
+ return evm_calc_hmac_or_hash(dentry, req_xattr_name, req_xattr_value,
+ req_xattr_value_len, EVM_XATTR_HMAC, digest);
+}
+
+int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name,
+ const char *req_xattr_value, size_t req_xattr_value_len,
+ char *digest)
+{
+ return evm_calc_hmac_or_hash(dentry, req_xattr_name, req_xattr_value,
+ req_xattr_value_len, IMA_XATTR_DIGEST, digest);
+}
+
/*
* Calculate the hmac and update security.evm xattr
*
@@ -186,7 +216,7 @@ int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr,
{
struct shash_desc *desc;
- desc = init_desc();
+ desc = init_desc(EVM_XATTR_HMAC);
if (IS_ERR(desc)) {
printk(KERN_INFO "init_desc failed\n");
return PTR_ERR(desc);