lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20150528154634.1259.89664.stgit@warthog.procyon.org.uk>
Date:	Thu, 28 May 2015 16:46:34 +0100
From:	David Howells <dhowells@...hat.com>
To:	mcgrof@...il.com
Cc:	mjg59@...f.ucam.org, keyrings@...ux-nfs.org,
	gregkh@...uxfoundation.org, kyle@...nel.org,
	linux-wireless@...r.kernel.org, linux-kernel@...r.kernel.org,
	seth.forshee@...onical.com, linux-security-module@...r.kernel.org,
	zohar@...ux.vnet.ibm.com, dwmw2@...radead.org
Subject: [PATCH 03/20] PKCS#7: Allow detached data to be supplied for
 signature checking purposes [ver #5]

It is possible for a PKCS#7 message to have detached data.  However, to verify
the signatures on a PKCS#7 message, we have to be able to digest the data.
Provide a function to supply that data.  An error is given if the PKCS#7
message included embedded data.

This is used in a subsequent patch to supply the data to module signing where
the signature is in the form of a PKCS#7 message with detached data, whereby
the detached data is the module content that is signed.

Signed-off-by: David Howells <dhowells@...hat.com>
Tested-by: Vivek Goyal <vgoyal@...hat.com>
---

 crypto/asymmetric_keys/pkcs7_verify.c |   25 +++++++++++++++++++++++++
 include/crypto/pkcs7.h                |    3 +++
 2 files changed, 28 insertions(+)

diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c
index 42bfc9de0d79..404f89a0f852 100644
--- a/crypto/asymmetric_keys/pkcs7_verify.c
+++ b/crypto/asymmetric_keys/pkcs7_verify.c
@@ -382,3 +382,28 @@ int pkcs7_verify(struct pkcs7_message *pkcs7)
 	return enopkg;
 }
 EXPORT_SYMBOL_GPL(pkcs7_verify);
+
+/**
+ * pkcs7_supply_detached_data - Supply the data needed to verify a PKCS#7 message
+ * @pkcs7: The PKCS#7 message
+ * @data: The data to be verified
+ * @datalen: The amount of data
+ *
+ * Supply the detached data needed to verify a PKCS#7 message.  Note that no
+ * attempt to retain/pin the data is made.  That is left to the caller.  The
+ * data will not be modified by pkcs7_verify() and will not be freed when the
+ * PKCS#7 message is freed.
+ *
+ * Returns -EINVAL if data is already supplied in the message, 0 otherwise.
+ */
+int pkcs7_supply_detached_data(struct pkcs7_message *pkcs7,
+			       const void *data, size_t datalen)
+{
+	if (pkcs7->data) {
+		pr_debug("Data already supplied\n");
+		return -EINVAL;
+	}
+	pkcs7->data = data;
+	pkcs7->data_len = datalen;
+	return 0;
+}
diff --git a/include/crypto/pkcs7.h b/include/crypto/pkcs7.h
index 691c79172a26..e235ab4957ee 100644
--- a/include/crypto/pkcs7.h
+++ b/include/crypto/pkcs7.h
@@ -34,3 +34,6 @@ extern int pkcs7_validate_trust(struct pkcs7_message *pkcs7,
  * pkcs7_verify.c
  */
 extern int pkcs7_verify(struct pkcs7_message *pkcs7);
+
+extern int pkcs7_supply_detached_data(struct pkcs7_message *pkcs7,
+				      const void *data, size_t datalen);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ