linux-security-module.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Roberto Sassu <roberto.sassu@huawei.com>
To: <zohar@linux.ibm.com>, <jarkko.sakkinen@linux.intel.com>,
	<james.bottomley@hansenpartnership.com>,
	<linux-integrity@vger.kernel.org>
Cc: <linux-security-module@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>, <silviu.vlasceanu@huawei.com>,
	Roberto Sassu <roberto.sassu@huawei.com>
Subject: [PATCH 5/8] ima: allocate and initialize tfm for each PCR bank
Date: Mon, 27 Jan 2020 18:04:40 +0100	[thread overview]
Message-ID: <20200127170443.21538-6-roberto.sassu@huawei.com> (raw)
In-Reply-To: <20200127170443.21538-1-roberto.sassu@huawei.com>

This patch creates a crypto_shash structure for each allocated PCR bank and
for SHA1 if a bank with that algorithm is not currently allocated.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
 security/integrity/ima/ima_crypto.c | 137 +++++++++++++++++++++++-----
 1 file changed, 113 insertions(+), 24 deletions(-)

diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 57b06321d5c8..63fb4bdf80b0 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -59,7 +59,14 @@ MODULE_PARM_DESC(ahash_bufsize, "Maximum ahash buffer size");
 static struct crypto_shash *ima_shash_tfm;
 static struct crypto_ahash *ima_ahash_tfm;
 
-int __init ima_init_crypto(void)
+struct ima_algo_desc {
+	struct crypto_shash *tfm;
+	enum hash_algo algo;
+};
+
+static struct ima_algo_desc *ima_algo_array;
+
+int __init ima_init_ima_crypto(void)
 {
 	long rc;
 
@@ -78,26 +85,116 @@ int __init ima_init_crypto(void)
 static struct crypto_shash *ima_alloc_tfm(enum hash_algo algo)
 {
 	struct crypto_shash *tfm = ima_shash_tfm;
-	int rc;
+	int rc, i;
 
 	if (algo < 0 || algo >= HASH_ALGO__LAST)
 		algo = ima_hash_algo;
 
-	if (algo != ima_hash_algo) {
-		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);
-		}
+	if (algo == ima_hash_algo)
+		return tfm;
+
+	for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++)
+		if (ima_algo_array[i].algo == algo && ima_algo_array[i].tfm)
+			return ima_algo_array[i].tfm;
+
+	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;
 }
 
+int __init ima_init_crypto(void)
+{
+	enum hash_algo algo;
+	long rc;
+	int i;
+
+	rc = ima_init_ima_crypto();
+	if (rc)
+		return rc;
+
+	ima_algo_array = kmalloc_array(ima_tpm_chip->nr_allocated_banks + 1,
+				       sizeof(*ima_algo_array), GFP_KERNEL);
+	if (!ima_algo_array) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++) {
+		ima_algo_array[i].tfm = NULL;
+		ima_algo_array[i].algo = HASH_ALGO__LAST;
+	}
+
+	ima_sha1_idx = -1;
+
+	for (i = 0; i < ima_tpm_chip->nr_allocated_banks; i++) {
+		algo = ima_tpm_chip->allocated_banks[i].crypto_id;
+		ima_algo_array[i].algo = algo;
+
+		/* unknown TPM algorithm */
+		if (algo == HASH_ALGO__LAST)
+			continue;
+
+		if (algo == HASH_ALGO_SHA1)
+			ima_sha1_idx = i;
+
+		if (algo == ima_hash_algo) {
+			ima_algo_array[i].tfm = ima_shash_tfm;
+			continue;
+		}
+
+		ima_algo_array[i].tfm = ima_alloc_tfm(algo);
+		if (IS_ERR(ima_algo_array[i].tfm)) {
+			if (algo == HASH_ALGO_SHA1) {
+				rc = PTR_ERR(ima_algo_array[i].tfm);
+				ima_algo_array[i].tfm = NULL;
+				goto out_array;
+			}
+
+			ima_algo_array[i].tfm = NULL;
+		}
+	}
+
+	if (ima_sha1_idx < 0) {
+		ima_algo_array[i].tfm = ima_alloc_tfm(HASH_ALGO_SHA1);
+		if (IS_ERR(ima_algo_array[i].tfm)) {
+			rc = PTR_ERR(ima_algo_array[i].tfm);
+			goto out_array;
+		}
+
+		ima_sha1_idx = i;
+		ima_algo_array[i].algo = HASH_ALGO_SHA1;
+	}
+
+	return 0;
+out_array:
+	for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++) {
+		if (!ima_algo_array[i].tfm ||
+		    ima_algo_array[i].tfm == ima_shash_tfm)
+			continue;
+
+		crypto_free_shash(ima_algo_array[i].tfm);
+	}
+out:
+	crypto_free_shash(ima_shash_tfm);
+	return rc;
+}
+
 static void ima_free_tfm(struct crypto_shash *tfm)
 {
-	if (tfm != ima_shash_tfm)
-		crypto_free_shash(tfm);
+	int i;
+
+	if (tfm == ima_shash_tfm)
+		return;
+
+	for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++)
+		if (ima_algo_array[i].tfm == tfm)
+			return;
+
+	crypto_free_shash(tfm);
 }
 
 /**
@@ -467,14 +564,14 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash)
  */
 static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 					 struct ima_template_entry *entry,
-					 struct crypto_shash *tfm)
+					 int tfm_idx)
 {
-	SHASH_DESC_ON_STACK(shash, tfm);
+	SHASH_DESC_ON_STACK(shash, ima_algo_array[tfm_idx].tfm);
 	struct ima_template_desc *td = entry->template_desc;
 	int num_fields = entry->template_desc->num_fields;
 	int rc, i;
 
-	shash->tfm = tfm;
+	shash->tfm = ima_algo_array[tfm_idx].tfm;
 
 	rc = crypto_shash_init(shash);
 	if (rc != 0)
@@ -505,7 +602,7 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 
 	if (!rc)
 		rc = crypto_shash_final(shash,
-					entry->digests[ima_sha1_idx].digest);
+					entry->digests[tfm_idx].digest);
 
 	return rc;
 }
@@ -513,17 +610,9 @@ static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data,
 int ima_calc_field_array_hash(struct ima_field_data *field_data,
 			      struct ima_template_entry *entry)
 {
-	struct crypto_shash *tfm;
 	int rc;
 
-	tfm = ima_alloc_tfm(HASH_ALGO_SHA1);
-	if (IS_ERR(tfm))
-		return PTR_ERR(tfm);
-
-	rc = ima_calc_field_array_hash_tfm(field_data, entry, tfm);
-
-	ima_free_tfm(tfm);
-
+	rc = ima_calc_field_array_hash_tfm(field_data, entry, ima_sha1_idx);
 	return rc;
 }
 
-- 
2.17.1


  parent reply	other threads:[~2020-01-27 17:06 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-27 17:04 [PATCH 0/8] ima: support stronger algorithms for attestation Roberto Sassu
2020-01-27 17:04 ` [PATCH 1/8] tpm: initialize crypto_id of allocated_banks to HASH_ALGO__LAST Roberto Sassu
2020-01-29  8:39   ` Petr Vorel
2020-01-30  8:47   ` Jarkko Sakkinen
2020-01-30 16:11     ` Roberto Sassu
2020-01-31 13:33       ` Mimi Zohar
2020-02-01 17:10         ` Jarkko Sakkinen
2020-01-27 17:04 ` [PATCH 2/8] ima: evaluate error in init_ima() Roberto Sassu
2020-01-31 13:33   ` Mimi Zohar
2020-01-27 17:04 ` [PATCH 3/8] ima: store template digest directly in ima_template_entry Roberto Sassu
2020-01-27 17:04 ` [PATCH 4/8] ima: switch to dynamically allocated buffer for template digests Roberto Sassu
2020-01-27 17:04 ` Roberto Sassu [this message]
2020-01-31 12:18   ` [PATCH 5/8] ima: allocate and initialize tfm for each PCR bank Mimi Zohar
2020-01-31 13:42     ` Roberto Sassu
2020-01-31 13:58       ` Mimi Zohar
2020-01-27 17:04 ` [PATCH 6/8] ima: calculate and extend PCR with digests in ima_template_entry Roberto Sassu
2020-01-27 17:29   ` Roberto Sassu
2020-01-27 17:04 ` [PATCH 7/8] ima: use ima_hash_algo for collision detection in the measurement list Roberto Sassu
2020-01-30 22:26   ` Mimi Zohar
2020-01-31 14:02     ` Roberto Sassu
2020-01-31 14:22       ` Mimi Zohar
2020-01-31 14:41         ` Roberto Sassu
2020-01-31 14:50           ` Mimi Zohar
2020-01-27 17:04 ` [PATCH 8/8] ima: switch to ima_hash_algo for boot aggregate Roberto Sassu
2020-01-31 15:21   ` Roberto Sassu
2020-01-30 22:26 ` [PATCH 0/8] ima: support stronger algorithms for attestation Mimi Zohar

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200127170443.21538-6-roberto.sassu@huawei.com \
    --to=roberto.sassu@huawei.com \
    --cc=james.bottomley@hansenpartnership.com \
    --cc=jarkko.sakkinen@linux.intel.com \
    --cc=linux-integrity@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=silviu.vlasceanu@huawei.com \
    --cc=zohar@linux.ibm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).