linux/include/keys/trusted-type.h

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/* SPDX-License-Identifier: GPL-2.0-only */
keys: add new trusted key-type Define a new kernel key-type called 'trusted'. Trusted keys are random number symmetric keys, generated and RSA-sealed by the TPM. The TPM only unseals the keys, if the boot PCRs and other criteria match. Userspace can only ever see encrypted blobs. Based on suggestions by Jason Gunthorpe, several new options have been added to support additional usages. The new options are: migratable= designates that the key may/may not ever be updated (resealed under a new key, new pcrinfo or new auth.) pcrlock=n extends the designated PCR 'n' with a random value, so that a key sealed to that PCR may not be unsealed again until after a reboot. keyhandle= specifies the sealing/unsealing key handle. keyauth= specifies the sealing/unsealing key auth. blobauth= specifies the sealed data auth. Implementation of a kernel reserved locality for trusted keys will be investigated for a possible future extension. Changelog: - Updated and added examples to Documentation/keys-trusted-encrypted.txt - Moved generic TPM constants to include/linux/tpm_command.h (David Howell's suggestion.) - trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure error handling, added const qualifiers where appropriate. - moved to late_initcall - updated from hash to shash (suggestion by David Howells) - reduced worst stack usage (tpm_seal) from 530 to 312 bytes - moved documentation to Documentation directory (suggestion by David Howells) - all the other code cleanups suggested by David Howells - Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe) - New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on discussions with Jason Gunthorpe) - Free payload on failure to create key(reported/fixed by Roberto Sassu) - Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion) - Replaced kzalloc() with kmalloc() (reported by Serge Hallyn) Signed-off-by: David Safford <safford@watson.ibm.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-11-23 22:50:34 +00:00
/*
* Copyright (C) 2010 IBM Corporation
* Author: David Safford <safford@us.ibm.com>
*/
#ifndef _KEYS_TRUSTED_TYPE_H
#define _KEYS_TRUSTED_TYPE_H
#include <linux/key.h>
#include <linux/rcupdate.h>
#include <linux/tpm.h>
keys: add new trusted key-type Define a new kernel key-type called 'trusted'. Trusted keys are random number symmetric keys, generated and RSA-sealed by the TPM. The TPM only unseals the keys, if the boot PCRs and other criteria match. Userspace can only ever see encrypted blobs. Based on suggestions by Jason Gunthorpe, several new options have been added to support additional usages. The new options are: migratable= designates that the key may/may not ever be updated (resealed under a new key, new pcrinfo or new auth.) pcrlock=n extends the designated PCR 'n' with a random value, so that a key sealed to that PCR may not be unsealed again until after a reboot. keyhandle= specifies the sealing/unsealing key handle. keyauth= specifies the sealing/unsealing key auth. blobauth= specifies the sealed data auth. Implementation of a kernel reserved locality for trusted keys will be investigated for a possible future extension. Changelog: - Updated and added examples to Documentation/keys-trusted-encrypted.txt - Moved generic TPM constants to include/linux/tpm_command.h (David Howell's suggestion.) - trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure error handling, added const qualifiers where appropriate. - moved to late_initcall - updated from hash to shash (suggestion by David Howells) - reduced worst stack usage (tpm_seal) from 530 to 312 bytes - moved documentation to Documentation directory (suggestion by David Howells) - all the other code cleanups suggested by David Howells - Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe) - New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on discussions with Jason Gunthorpe) - Free payload on failure to create key(reported/fixed by Roberto Sassu) - Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion) - Replaced kzalloc() with kmalloc() (reported by Serge Hallyn) Signed-off-by: David Safford <safford@watson.ibm.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-11-23 22:50:34 +00:00
#ifdef pr_fmt
#undef pr_fmt
#endif
#define pr_fmt(fmt) "trusted_key: " fmt
keys: add new trusted key-type Define a new kernel key-type called 'trusted'. Trusted keys are random number symmetric keys, generated and RSA-sealed by the TPM. The TPM only unseals the keys, if the boot PCRs and other criteria match. Userspace can only ever see encrypted blobs. Based on suggestions by Jason Gunthorpe, several new options have been added to support additional usages. The new options are: migratable= designates that the key may/may not ever be updated (resealed under a new key, new pcrinfo or new auth.) pcrlock=n extends the designated PCR 'n' with a random value, so that a key sealed to that PCR may not be unsealed again until after a reboot. keyhandle= specifies the sealing/unsealing key handle. keyauth= specifies the sealing/unsealing key auth. blobauth= specifies the sealed data auth. Implementation of a kernel reserved locality for trusted keys will be investigated for a possible future extension. Changelog: - Updated and added examples to Documentation/keys-trusted-encrypted.txt - Moved generic TPM constants to include/linux/tpm_command.h (David Howell's suggestion.) - trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure error handling, added const qualifiers where appropriate. - moved to late_initcall - updated from hash to shash (suggestion by David Howells) - reduced worst stack usage (tpm_seal) from 530 to 312 bytes - moved documentation to Documentation directory (suggestion by David Howells) - all the other code cleanups suggested by David Howells - Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe) - New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on discussions with Jason Gunthorpe) - Free payload on failure to create key(reported/fixed by Roberto Sassu) - Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion) - Replaced kzalloc() with kmalloc() (reported by Serge Hallyn) Signed-off-by: David Safford <safford@watson.ibm.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-11-23 22:50:34 +00:00
#define MIN_KEY_SIZE 32
#define MAX_KEY_SIZE 128
#define MAX_BLOB_SIZE 512
#define MAX_PCRINFO_SIZE 64
#define MAX_DIGEST_SIZE 64
keys: add new trusted key-type Define a new kernel key-type called 'trusted'. Trusted keys are random number symmetric keys, generated and RSA-sealed by the TPM. The TPM only unseals the keys, if the boot PCRs and other criteria match. Userspace can only ever see encrypted blobs. Based on suggestions by Jason Gunthorpe, several new options have been added to support additional usages. The new options are: migratable= designates that the key may/may not ever be updated (resealed under a new key, new pcrinfo or new auth.) pcrlock=n extends the designated PCR 'n' with a random value, so that a key sealed to that PCR may not be unsealed again until after a reboot. keyhandle= specifies the sealing/unsealing key handle. keyauth= specifies the sealing/unsealing key auth. blobauth= specifies the sealed data auth. Implementation of a kernel reserved locality for trusted keys will be investigated for a possible future extension. Changelog: - Updated and added examples to Documentation/keys-trusted-encrypted.txt - Moved generic TPM constants to include/linux/tpm_command.h (David Howell's suggestion.) - trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure error handling, added const qualifiers where appropriate. - moved to late_initcall - updated from hash to shash (suggestion by David Howells) - reduced worst stack usage (tpm_seal) from 530 to 312 bytes - moved documentation to Documentation directory (suggestion by David Howells) - all the other code cleanups suggested by David Howells - Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe) - New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on discussions with Jason Gunthorpe) - Free payload on failure to create key(reported/fixed by Roberto Sassu) - Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion) - Replaced kzalloc() with kmalloc() (reported by Serge Hallyn) Signed-off-by: David Safford <safford@watson.ibm.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-11-23 22:50:34 +00:00
struct trusted_key_payload {
struct rcu_head rcu;
unsigned int key_len;
unsigned int blob_len;
unsigned char migratable;
unsigned char old_format;
keys: add new trusted key-type Define a new kernel key-type called 'trusted'. Trusted keys are random number symmetric keys, generated and RSA-sealed by the TPM. The TPM only unseals the keys, if the boot PCRs and other criteria match. Userspace can only ever see encrypted blobs. Based on suggestions by Jason Gunthorpe, several new options have been added to support additional usages. The new options are: migratable= designates that the key may/may not ever be updated (resealed under a new key, new pcrinfo or new auth.) pcrlock=n extends the designated PCR 'n' with a random value, so that a key sealed to that PCR may not be unsealed again until after a reboot. keyhandle= specifies the sealing/unsealing key handle. keyauth= specifies the sealing/unsealing key auth. blobauth= specifies the sealed data auth. Implementation of a kernel reserved locality for trusted keys will be investigated for a possible future extension. Changelog: - Updated and added examples to Documentation/keys-trusted-encrypted.txt - Moved generic TPM constants to include/linux/tpm_command.h (David Howell's suggestion.) - trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure error handling, added const qualifiers where appropriate. - moved to late_initcall - updated from hash to shash (suggestion by David Howells) - reduced worst stack usage (tpm_seal) from 530 to 312 bytes - moved documentation to Documentation directory (suggestion by David Howells) - all the other code cleanups suggested by David Howells - Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe) - New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on discussions with Jason Gunthorpe) - Free payload on failure to create key(reported/fixed by Roberto Sassu) - Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion) - Replaced kzalloc() with kmalloc() (reported by Serge Hallyn) Signed-off-by: David Safford <safford@watson.ibm.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-11-23 22:50:34 +00:00
unsigned char key[MAX_KEY_SIZE + 1];
unsigned char blob[MAX_BLOB_SIZE];
};
struct trusted_key_options {
uint16_t keytype;
uint32_t keyhandle;
unsigned char keyauth[TPM_DIGEST_SIZE];
security: keys: trusted: fix TPM2 authorizations In TPM 1.2 an authorization was a 20 byte number. The spec actually recommended you to hash variable length passwords and use the sha1 hash as the authorization. Because the spec doesn't require this hashing, the current authorization for trusted keys is a 40 digit hex number. For TPM 2.0 the spec allows the passing in of variable length passwords and passphrases directly, so we should allow that in trusted keys for ease of use. Update the 'blobauth' parameter to take this into account, so we can now use plain text passwords for the keys. so before keyctl add trusted kmk "new 32 blobauth=f572d396fae9206628714fb2ce00f72e94f2258fkeyhandle=81000001" @u after we will accept both the old hex sha1 form as well as a new directly supplied password: keyctl add trusted kmk "new 32 blobauth=hello keyhandle=81000001" @u Since a sha1 hex code must be exactly 40 bytes long and a direct password must be 20 or less, we use the length as the discriminator for which form is input. Note this is both and enhancement and a potential bug fix. The TPM 2.0 spec requires us to strip leading zeros, meaning empyty authorization is a zero length HMAC whereas we're currently passing in 20 bytes of zeros. A lot of TPMs simply accept this as OK, but the Microsoft TPM emulator rejects it with TPM_RC_BAD_AUTH, so this patch makes the Microsoft TPM emulator work with trusted keys. Fixes: 0fe5480303a1 ("keys, trusted: seal/unseal with TPM 2.0 chips") Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2021-01-27 19:06:15 +00:00
uint32_t blobauth_len;
unsigned char blobauth[TPM_DIGEST_SIZE];
uint32_t pcrinfo_len;
unsigned char pcrinfo[MAX_PCRINFO_SIZE];
int pcrlock;
uint32_t hash;
uint32_t policydigest_len;
unsigned char policydigest[MAX_DIGEST_SIZE];
uint32_t policyhandle;
};
struct trusted_key_ops {
/*
* flag to indicate if trusted key implementation supports migration
* or not.
*/
unsigned char migratable;
/* Initialize key interface. */
int (*init)(void);
/* Seal a key. */
int (*seal)(struct trusted_key_payload *p, char *datablob);
/* Unseal a key. */
int (*unseal)(struct trusted_key_payload *p, char *datablob);
/* Get a randomized key. */
int (*get_random)(unsigned char *key, size_t key_len);
/* Exit key interface. */
void (*exit)(void);
};
struct trusted_key_source {
char *name;
struct trusted_key_ops *ops;
};
keys: add new trusted key-type Define a new kernel key-type called 'trusted'. Trusted keys are random number symmetric keys, generated and RSA-sealed by the TPM. The TPM only unseals the keys, if the boot PCRs and other criteria match. Userspace can only ever see encrypted blobs. Based on suggestions by Jason Gunthorpe, several new options have been added to support additional usages. The new options are: migratable= designates that the key may/may not ever be updated (resealed under a new key, new pcrinfo or new auth.) pcrlock=n extends the designated PCR 'n' with a random value, so that a key sealed to that PCR may not be unsealed again until after a reboot. keyhandle= specifies the sealing/unsealing key handle. keyauth= specifies the sealing/unsealing key auth. blobauth= specifies the sealed data auth. Implementation of a kernel reserved locality for trusted keys will be investigated for a possible future extension. Changelog: - Updated and added examples to Documentation/keys-trusted-encrypted.txt - Moved generic TPM constants to include/linux/tpm_command.h (David Howell's suggestion.) - trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure error handling, added const qualifiers where appropriate. - moved to late_initcall - updated from hash to shash (suggestion by David Howells) - reduced worst stack usage (tpm_seal) from 530 to 312 bytes - moved documentation to Documentation directory (suggestion by David Howells) - all the other code cleanups suggested by David Howells - Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe) - New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on discussions with Jason Gunthorpe) - Free payload on failure to create key(reported/fixed by Roberto Sassu) - Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion) - Replaced kzalloc() with kmalloc() (reported by Serge Hallyn) Signed-off-by: David Safford <safford@watson.ibm.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-11-23 22:50:34 +00:00
extern struct key_type key_type_trusted;
#define TRUSTED_DEBUG 0
#if TRUSTED_DEBUG
static inline void dump_payload(struct trusted_key_payload *p)
{
pr_info("key_len %d\n", p->key_len);
print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
16, 1, p->key, p->key_len, 0);
pr_info("bloblen %d\n", p->blob_len);
print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
16, 1, p->blob, p->blob_len, 0);
pr_info("migratable %d\n", p->migratable);
}
#else
static inline void dump_payload(struct trusted_key_payload *p)
{
}
#endif
keys: add new trusted key-type Define a new kernel key-type called 'trusted'. Trusted keys are random number symmetric keys, generated and RSA-sealed by the TPM. The TPM only unseals the keys, if the boot PCRs and other criteria match. Userspace can only ever see encrypted blobs. Based on suggestions by Jason Gunthorpe, several new options have been added to support additional usages. The new options are: migratable= designates that the key may/may not ever be updated (resealed under a new key, new pcrinfo or new auth.) pcrlock=n extends the designated PCR 'n' with a random value, so that a key sealed to that PCR may not be unsealed again until after a reboot. keyhandle= specifies the sealing/unsealing key handle. keyauth= specifies the sealing/unsealing key auth. blobauth= specifies the sealed data auth. Implementation of a kernel reserved locality for trusted keys will be investigated for a possible future extension. Changelog: - Updated and added examples to Documentation/keys-trusted-encrypted.txt - Moved generic TPM constants to include/linux/tpm_command.h (David Howell's suggestion.) - trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure error handling, added const qualifiers where appropriate. - moved to late_initcall - updated from hash to shash (suggestion by David Howells) - reduced worst stack usage (tpm_seal) from 530 to 312 bytes - moved documentation to Documentation directory (suggestion by David Howells) - all the other code cleanups suggested by David Howells - Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe) - New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on discussions with Jason Gunthorpe) - Free payload on failure to create key(reported/fixed by Roberto Sassu) - Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion) - Replaced kzalloc() with kmalloc() (reported by Serge Hallyn) Signed-off-by: David Safford <safford@watson.ibm.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-11-23 22:50:34 +00:00
#endif /* _KEYS_TRUSTED_TYPE_H */