/* Public keys for module signature verification * * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * 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. */ #include <linux/kernel.h> #include <linux/sched.h> #include <linux/cred.h> #include <linux/err.h> #include <keys/asymmetric-type.h> #include "module-internal.h" struct key *modsign_keyring; extern __initconst const u8 modsign_certificate_list[]; extern __initconst const u8 modsign_certificate_list_end[]; /* * We need to make sure ccache doesn't cache the .o file as it doesn't notice * if modsign.pub changes. */ static __initconst const char annoy_ccache[] = __TIME__ "foo"; /* * Load the compiled-in keys */ static __init int module_verify_init(void) { pr_notice("Initialise module verification\n"); modsign_keyring = keyring_alloc(".module_sign", KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), ((KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW | KEY_USR_READ), KEY_ALLOC_NOT_IN_QUOTA, NULL); if (IS_ERR(modsign_keyring)) panic("Can't allocate module signing keyring\n"); return 0; } /* * Must be initialised before we try and load the keys into the keyring. */ device_initcall(module_verify_init); /* * Load the compiled-in keys */ static __init int load_module_signing_keys(void) { key_ref_t key; const u8 *p, *end; size_t plen; pr_notice("Loading module verification certificates\n"); end = modsign_certificate_list_end; p = modsign_certificate_list; while (p < end) { /* Each cert begins with an ASN.1 SEQUENCE tag and must be more * than 256 bytes in size. */ if (end - p < 4) goto dodgy_cert; if (p[0] != 0x30 && p[1] != 0x82) goto dodgy_cert; plen = (p[2] << 8) | p[3]; plen += 4; if (plen > end - p) goto dodgy_cert; key = key_create_or_update(make_key_ref(modsign_keyring, 1), "asymmetric", NULL, p, plen, (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW, KEY_ALLOC_NOT_IN_QUOTA); if (IS_ERR(key)) pr_err("MODSIGN: Problem loading in-kernel X.509 certificate (%ld)\n", PTR_ERR(key)); else pr_notice("MODSIGN: Loaded cert '%s'\n", key_ref_to_ptr(key)->description); p += plen; } return 0; dodgy_cert: pr_err("MODSIGN: Problem parsing in-kernel X.509 certificate list\n"); return 0; } late_initcall(load_module_signing_keys);