docs: move digsig docs to the security book

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6af5365404c7bd9d008e7e3a77ba83587fd33012.1588345503.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

1 files changed, 0 insertions, 101 deletions

diff --git a/Documentation/digsig.txt b/Documentation/digsig.txt
deleted file mode 100644
index f6a8902d3ef7..000000000000
--- a/Documentation/digsig.txt
+++ /dev/null
@@ -1,101 +0,0 @@
-==================================
-Digital Signature Verification API
-==================================
-
-:Author: Dmitry Kasatkin
-:Date: 06.10.2011
-
-
-.. CONTENTS
-
-   1. Introduction
-   2. API
-   3. User-space utilities
-
-
-Introduction
-============
-
-Digital signature verification API provides a method to verify digital signature.
-Currently digital signatures are used by the IMA/EVM integrity protection subsystem.
-
-Digital signature verification is implemented using cut-down kernel port of
-GnuPG multi-precision integers (MPI) library. The kernel port provides
-memory allocation errors handling, has been refactored according to kernel
-coding style, and checkpatch.pl reported errors and warnings have been fixed.
-
-Public key and signature consist of header and MPIs::
-
-	struct pubkey_hdr {
-		uint8_t		version;	/* key format version */
-		time_t		timestamp;	/* key made, always 0 for now */
-		uint8_t		algo;
-		uint8_t		nmpi;
-		char		mpi[0];
-	} __packed;
-
-	struct signature_hdr {
-		uint8_t		version;	/* signature format version */
-		time_t		timestamp;	/* signature made */
-		uint8_t		algo;
-		uint8_t		hash;
-		uint8_t		keyid[8];
-		uint8_t		nmpi;
-		char		mpi[0];
-	} __packed;
-
-keyid equals to SHA1[12-19] over the total key content.
-Signature header is used as an input to generate a signature.
-Such approach insures that key or signature header could not be changed.
-It protects timestamp from been changed and can be used for rollback
-protection.
-
-API
-===
-
-API currently includes only 1 function::
-
-	digsig_verify() - digital signature verification with public key
-
-
-	/**
-	* digsig_verify() - digital signature verification with public key
-	* @keyring:	keyring to search key in
-	* @sig:	digital signature
-	* @sigen:	length of the signature
-	* @data:	data
-	* @datalen:	length of the data
-	* @return:	0 on success, -EINVAL otherwise
-	*
-	* Verifies data integrity against digital signature.
-	* Currently only RSA is supported.
-	* Normally hash of the content is used as a data for this function.
-	*
-	*/
-	int digsig_verify(struct key *keyring, const char *sig, int siglen,
-			  const char *data, int datalen);
-
-User-space utilities
-====================
-
-The signing and key management utilities evm-utils provide functionality
-to generate signatures, to load keys into the kernel keyring.
-Keys can be in PEM or converted to the kernel format.
-When the key is added to the kernel keyring, the keyid defines the name
-of the key: 5D2B05FC633EE3E8 in the example bellow.
-
-Here is example output of the keyctl utility::
-
-	$ keyctl show
-	Session Keyring
-	-3 --alswrv      0     0  keyring: _ses
-	603976250 --alswrv      0    -1   \_ keyring: _uid.0
-	817777377 --alswrv      0     0       \_ user: kmk
-	891974900 --alswrv      0     0       \_ encrypted: evm-key
-	170323636 --alswrv      0     0       \_ keyring: _module
-	548221616 --alswrv      0     0       \_ keyring: _ima
-	128198054 --alswrv      0     0       \_ keyring: _evm
-
-	$ keyctl list 128198054
-	1 key in keyring:
-	620789745: --alswrv     0     0 user: 5D2B05FC633EE3E8