cregit-Linux how code gets into the kernel

Release 4.10 crypto/asymmetric_keys/restrict.c

/* Instantiate a public key crypto key from an X.509 Certificate
 * Copyright (C) 2012, 2016 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.

#define pr_fmt(fmt) "ASYM: "fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <crypto/public_key.h>
#include "asymmetric_keys.h"

static bool use_builtin_keys;

static struct asymmetric_key_id *ca_keyid;

#ifndef MODULE
static struct {
struct asymmetric_key_id id;
unsigned char data[10];

static int __init ca_keys_setup(char *str) { if (!str) /* default system keyring */ return 1; if (strncmp(str, "id:", 3) == 0) { struct asymmetric_key_id *p = &; size_t hexlen = (strlen(str) - 3) / 2; int ret; if (hexlen == 0 || hexlen > sizeof( { pr_err("Missing or invalid ca_keys id\n"); return 1; } ret = __asymmetric_key_hex_to_key_id(str + 3, p, hexlen); if (ret < 0) pr_err("Unparsable ca_keys id hex string\n"); else ca_keyid = p; /* owner key 'id:xxxxxx' */ } else if (strcmp(str, "builtin") == 0) { use_builtin_keys = true; } return 1; }


david howellsdavid howells138100.00%1100.00%

__setup("ca_keys=", ca_keys_setup); #endif /** * restrict_link_by_signature - Restrict additions to a ring of public keys * @trust_keyring: A ring of keys that can be used to vouch for the new cert. * @type: The type of key being added. * @payload: The payload of the new key. * * Check the new certificate against the ones in the trust keyring. If one of * those is the signing key and validates the new certificate, then mark the * new certificate as being trusted. * * Returns 0 if the new certificate was accepted, -ENOKEY if we couldn't find a * matching parent certificate in the trusted list, -EKEYREJECTED if the * signature check fails or the key is blacklisted and some other error if * there is a matching certificate but the signature check cannot be performed. */
int restrict_link_by_signature(struct key *trust_keyring, const struct key_type *type, const union key_payload *payload) { const struct public_key_signature *sig; struct key *key; int ret; pr_devel("==>%s()\n", __func__); if (!trust_keyring) return -ENOKEY; if (type != &key_type_asymmetric) return -EOPNOTSUPP; sig = payload->data[asym_auth]; if (!sig->auth_ids[0] && !sig->auth_ids[1]) return -ENOKEY; if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid)) return -EPERM; /* See if we have a key that signed this one. */ key = find_asymmetric_key(trust_keyring, sig->auth_ids[0], sig->auth_ids[1], false); if (IS_ERR(key)) return -ENOKEY; if (use_builtin_keys && !test_bit(KEY_FLAG_BUILTIN, &key->flags)) ret = -ENOKEY; else ret = verify_signature(key, sig); key_put(key); return ret; }


david howellsdavid howells18698.94%266.67%
mat martineaumat martineau21.06%133.33%

Overall Contributors

david howellsdavid howells38799.49%266.67%
mat martineaumat martineau20.51%133.33%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.