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Revision f32393c943e297b8ae180c8f83d81a156c7d0412 authored by Nathan Fontenot on 30 April 2015, 01:42:06 UTC, committed by Michael Ellerman on 01 May 2015, 03:47:24 UTC 
powerpc/pseries: Correct cpu affinity for dlpar added cpus
 
The incorrect ordering of operations during cpu dlpar add results in invalid
affinity for the cpu being added. The ibm,associativity property in the
device tree is populated with all zeroes for the added cpu which results in
invalid affinity mappings and all cpus appear to belong to node 0.

This occurs because rtas configure-connector is called prior to making the
rtas set-indicator calls. Phyp does not assign affinity information
for a cpu until the rtas set-indicator calls are made to set the isolation
and allocation state.

Correct the order of operations to make the rtas set-indicator
calls (done in dlpar_acquire_drc) before calling rtas configure-connector.

Fixes: 1a8061c46c46 ("powerpc/pseries: Add kernel based CPU DLPAR handling")

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
1 parent 2fa30fe
Raw File
digsig.txt 
Digital Signature Verification API

CONTENTS

1. Introduction
2. API
3. User-space utilities


1. 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.

2. 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);

3. 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


Dmitry Kasatkin
06.10.2011
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