2 * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20 FILE_LICENCE ( GPL2_OR_LATER );
23 #include <ipxe/crypto.h>
24 #include <ipxe/sha256.h>
25 #include <ipxe/x509.h>
26 #include <ipxe/settings.h>
27 #include <ipxe/dhcp.h>
28 #include <ipxe/init.h>
29 #include <ipxe/rootcert.h>
33 * Root certificate store
37 /** Length of a root certificate fingerprint */
38 #define FINGERPRINT_LEN SHA256_DIGEST_SIZE
40 /* Allow trusted certificates to be overridden if not explicitly specified */
42 #define ALLOW_TRUST_OVERRIDE 0
44 #define ALLOW_TRUST_OVERRIDE 1
47 /* Use iPXE root CA if no trusted certificates are explicitly specified */
51 0x9f, 0xaf, 0x71, 0x7b, 0x7f, 0x8c, 0xa2, 0xf9, 0x3c, 0x25, \
52 0x6c, 0x79, 0xf8, 0xac, 0x55, 0x91, 0x89, 0x5d, 0x66, 0xd1, \
53 0xff, 0x3b, 0xee, 0x63, 0x97, 0xa7, 0x0d, 0x29, 0xc6, 0x5e, \
57 /** Root certificate fingerprints */
58 static const uint8_t fingerprints[] = { TRUSTED };
60 /** Root certificate fingerprint setting */
61 static struct setting trust_setting __setting ( SETTING_CRYPTO, trust ) = {
63 .description = "Trusted root certificate fingerprints",
65 .type = &setting_type_hex,
68 /** Root certificates */
69 struct x509_root root_certificates = {
70 .digest = &sha256_algorithm,
71 .count = ( sizeof ( fingerprints ) / FINGERPRINT_LEN ),
72 .fingerprints = fingerprints,
76 * Initialise root certificate
78 * The list of trusted root certificates can be specified at build
79 * time using the TRUST= build parameter. If no certificates are
80 * specified, then the default iPXE root CA certificate is trusted.
82 * If no certificates were explicitly specified, then we allow the
83 * list of trusted root certificate fingerprints to be overridden
84 * using the "trust" setting, but only at the point of iPXE
85 * initialisation. This prevents untrusted sources of settings
86 * (e.g. DHCP) from subverting the chain of trust, while allowing
87 * trustworthy sources (e.g. VMware GuestInfo or non-volatile stored
88 * options) to specify the trusted root certificate without requiring
91 static void rootcert_init ( void ) {
92 void *external = NULL;
95 /* Allow trusted root certificates to be overridden only if
96 * not explicitly specified at build time.
98 if ( ALLOW_TRUST_OVERRIDE ) {
100 /* Fetch copy of "trust" setting, if it exists. This
101 * memory will never be freed.
103 if ( ( len = fetch_raw_setting_copy ( NULL, &trust_setting,
104 &external ) ) >= 0 ) {
105 root_certificates.fingerprints = external;
106 root_certificates.count = ( len / FINGERPRINT_LEN );
110 DBGC ( &root_certificates, "ROOTCERT using %d %s certificate(s):\n",
111 root_certificates.count, ( external ? "external" : "built-in" ));
112 DBGC_HDA ( &root_certificates, 0, root_certificates.fingerprints,
113 ( root_certificates.count * FINGERPRINT_LEN ) );
116 /** Root certificate initialiser */
117 struct init_fn rootcert_init_fn __init_fn ( INIT_LATE ) = {
118 .initialise = rootcert_init,