/*
* Copyright (C) 2012 Red Hat Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
* * Redistributions in binary form must reproduce the
* above copyright notice, this list of conditions and
* the following disclaimer in the documentation and/or
* other materials provided with the distribution.
* * The names of contributors to this software may not be
* used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
* THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* Author: Stef Walter <stefw@redhat.com>
*/
#include "config.h"
#include "array.h"
#include "asn1.h"
#include "attrs.h"
#define P11_DEBUG_FLAG P11_DEBUG_TRUST
#include "debug.h"
#include "dict.h"
#include "digest.h"
#include "message.h"
#include "module.h"
#include "oid.h"
#include "parser.h"
#include "path.h"
#include "pem.h"
#include "pkcs11x.h"
#include "persist.h"
#include "types.h"
#include "x509.h"
#include <libtasn1.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
struct _p11_parser {
p11_asn1_cache *asn1_cache;
p11_dict *asn1_defs;
bool asn1_owned;
p11_persist *persist;
char *basename;
p11_array *parsed;
p11_array *formats;
int flags;
};
#define ID_LENGTH P11_DIGEST_SHA1_LEN
typedef int (* parser_func) (p11_parser *parser,
const unsigned char *data,
size_t length);
static CK_ATTRIBUTE *
populate_trust (p11_parser *parser,
CK_ATTRIBUTE *attrs)
{
CK_BBOOL trustedv;
CK_BBOOL distrustv;
CK_ATTRIBUTE trusted = { CKA_TRUSTED, &trustedv, sizeof (trustedv) };
CK_ATTRIBUTE distrust = { CKA_X_DISTRUSTED, &distrustv, sizeof (distrustv) };
/*
* If we're are parsing an anchor location, then warn about any ditsrusted
* certificates there, but don't go ahead and automatically make them
* trusted anchors.
*/
if (parser->flags & P11_PARSE_FLAG_ANCHOR) {
if (p11_attrs_find_bool (attrs, CKA_X_DISTRUSTED, &distrustv) && distrustv) {
p11_message ("certificate with distrust in location for anchors: %s", parser->basename);
return attrs;
}
trustedv = CK_TRUE;
distrustv = CK_FALSE;
/*
* If we're parsing a blacklist location, then force all certificates to
* be blacklisted, regardless of whether they contain anchor information.
*/
} else if (parser->flags & P11_PARSE_FLAG_BLACKLIST) {
if (p11_attrs_find_bool (attrs, CKA_TRUSTED, &trustedv) && trustedv)
p11_message ("overriding trust for anchor in blacklist: %s", parser->basename);
trustedv = CK_FALSE;
distrustv = CK_TRUE;
/*
* If the location doesn't have a flag, then fill in trust attributes
* if they are missing: neither an anchor or blacklist.
*/
} else {
trustedv = CK_FALSE;
distrustv = CK_FALSE;
if (p11_attrs_find_valid (attrs, CKA_TRUSTED))
trusted.type = CKA_INVALID;
if (p11_attrs_find_valid (attrs, CKA_X_DISTRUSTED))
distrust.type = CKA_INVALID;
}
return p11_attrs_build (attrs, &trusted, &distrust, NULL);
}
static void
sink_object (p11_parser *parser,
CK_ATTRIBUTE *attrs)
{
CK_OBJECT_CLASS klass;
if (p11_attrs_find_ulong (attrs, CKA_CLASS, &klass) &&
klass == CKO_CERTIFICATE) {
attrs = populate_trust (parser, attrs);
return_if_fail (attrs != NULL);
}
if (!p11_array_push (parser->parsed, attrs))
return_if_reached ();
}
static CK_ATTRIBUTE *
certificate_attrs (p11_parser *parser,
const unsigned char *der,
size_t der_len)
{
CK_OBJECT_CLASS klassv = CKO_CERTIFICATE;
CK_CERTIFICATE_TYPE x509 = CKC_X_509;
CK_BBOOL modifiablev = CK_FALSE;
CK_ATTRIBUTE modifiable = { CKA_MODIFIABLE, &modifiablev, sizeof (modifiablev) };
CK_ATTRIBUTE klass = { CKA_CLASS, &klassv, sizeof (klassv) };
CK_ATTRIBUTE certificate_type = { CKA_CERTIFICATE_TYPE, &x509, sizeof (x509) };
CK_ATTRIBUTE value = { CKA_VALUE, (void *)der, der_len };
return p11_attrs_build (NULL, &klass, &modifiable, &certificate_type, &value, NULL);
}
int
p11_parser_format_x509 (p11_parser *parser,
const unsigned char *data,
size_t length)
{
char message[ASN1_MAX_ERROR_DESCRIPTION_SIZE];
CK_ATTRIBUTE *attrs;
CK_ATTRIBUTE *value;
node_asn *cert;
cert = p11_asn1_decode (parser->asn1_defs, "PKIX1.Certificate", data, length, message);
if (cert == NULL)
return P11_PARSE_UNRECOGNIZED;
attrs = certificate_attrs (parser, data, length);
return_val_if_fail (attrs != NULL, P11_PARSE_FAILURE);
value = p11_attrs_find_valid (attrs, CKA_VALUE);
return_val_if_fail (value != NULL, P11_PARSE_FAILURE);
p11_asn1_cache_take (parser->asn1_cache, cert, "PKIX1.Certificate",
value->pValue, value->ulValueLen);
sink_object (parser, attrs);
return P11_PARSE_SUCCESS;
}
static CK_ATTRIBUTE *
extension_attrs (p11_parser *parser,
CK_ATTRIBUTE *public_key_info,
const char *oid_str,
const unsigned char *oid_der,
bool critical,
const unsigned char *value,
int length)
{
CK_OBJECT_CLASS klassv = CKO_X_CERTIFICATE_EXTENSION;
CK_BBOOL modifiablev = CK_FALSE;
CK_ATTRIBUTE klass = { CKA_CLASS, &klassv, sizeof (klassv) };
CK_ATTRIBUTE modifiable = { CKA_MODIFIABLE, &modifiablev, sizeof (modifiablev) };
CK_ATTRIBUTE oid = { CKA_OBJECT_ID, (void *)oid_der, p11_oid_length (oid_der) };
CK_ATTRIBUTE *attrs;
node_asn *dest;
unsigned char *der;
size_t len;
int ret;
attrs = p11_attrs_build (NULL, public_key_info, &klass, &modifiable, &oid, NULL);
return_val_if_fail (attrs != NULL, NULL);
dest = p11_asn1_create (parser->asn1_defs, "PKIX1.Extension");
return_val_if_fail (dest != NULL, NULL);
ret = asn1_write_value (dest, "extnID", oid_str, 1);
return_val_if_fail (ret == ASN1_SUCCESS, NULL);
if (critical)
ret = asn1_write_value (dest, "critical", "TRUE", 1);
return_val_if_fail (ret == ASN1_SUCCESS, NULL);
ret = asn1_write_value (dest, "extnValue", value, length);
return_val_if_fail (ret == ASN1_SUCCESS, NULL);
der = p11_asn1_encode (dest, &len);
return_val_if_fail (der != NULL, NULL);
attrs = p11_attrs_take (attrs, CKA_VALUE, der, len);
return_val_if_fail (attrs != NULL, NULL);
/* An opmitization so that the builder can get at this without parsing */
p11_asn1_cache_take (parser->asn1_cache, dest, "PKIX1.Extension", der, len);
return attrs;
}
static CK_ATTRIBUTE *
attached_attrs (p11_parser *parser,
CK_ATTRIBUTE *public_key_info,
const char *oid_str,
const unsigned char *oid_der,
bool critical,
node_asn *ext)
{
CK_ATTRIBUTE *attrs;
unsigned char *der;
size_t len;
der = p11_asn1_encode (ext, &len);
return_val_if_fail (der != NULL, NULL);
attrs = extension_attrs (parser, public_key_info, oid_str, oid_der,
critical, der, len);
return_val_if_fail (attrs != NULL, NULL);
free (der);
return attrs;
}
static p11_dict *
load_seq_of_oid_str (node_asn *node,
const char *seqof)
{
p11_dict *oids;
char field[128];
char *oid;
size_t len;
int i;
oids = p11_dict_new (p11_dict_str_hash, p11_dict_str_equal, free, NULL);
for (i = 1; ; i++) {
if (snprintf (field, sizeof (field), "%s.?%u", seqof, i) < 0)
return_val_if_reached (NULL);
oid = p11_asn1_read (node, field, &len);
if (oid == NULL)
break;
if (!p11_dict_set (oids, oid, oid))
return_val_if_reached (NULL);
}
return oids;
}
static CK_ATTRIBUTE *
attached_eku_attrs (p11_parser *parser,
CK_ATTRIBUTE *public_key_info,
const char *oid_str,
const unsigned char *oid_der,
bool critical,
p11_dict *oid_strs)
{
CK_ATTRIBUTE *attrs;
p11_dictiter iter;
node_asn *dest;
int count = 0;
void *value;
int ret;
dest = p11_asn1_create (parser->asn1_defs, "PKIX1.ExtKeyUsageSyntax");
return_val_if_fail (dest != NULL, NULL);
p11_dict_iterate (oid_strs, &iter);
while (p11_dict_next (&iter, NULL, &value)) {
ret = asn1_write_value (dest, "", "NEW", 1);
return_val_if_fail (ret == ASN1_SUCCESS, NULL);
ret = asn1_write_value (dest, "?LAST", value, -1);
return_val_if_fail (ret == ASN1_SUCCESS, NULL);
count++;
}
/*
* If no oids have been written, then we have to put in a reserved
* value, due to the way that ExtendedKeyUsage is defined in RFC 5280.
* There must be at least one purpose. This is important since *not*
* having an ExtendedKeyUsage is very different than having one without
* certain usages.
*
* We account for this in p11_parse_extended_key_usage(). However for
* most callers this should not matter, as they only check whether a
* given purpose is present, and don't make assumptions about ones
* that they don't know about.
*/
if (count == 0) {
ret = asn1_write_value (dest, "", "NEW", 1);
return_val_if_fail (ret == ASN1_SUCCESS, NULL);
ret = asn1_write_value (dest, "?LAST", P11_OID_RESERVED_PURPOSE_STR, -1);
return_val_if_fail (ret == ASN1_SUCCESS, NULL);
}
attrs = attached_attrs (parser, public_key_info, oid_str, oid_der, critical, dest);
asn1_delete_structure (&dest);
return attrs;
}
static CK_ATTRIBUTE *
build_openssl_extensions (p11_parser *parser,
CK_ATTRIBUTE *cert,
CK_ATTRIBUTE *public_key_info,
node_asn *aux,
const unsigned char *aux_der,
size_t aux_len)
{
CK_BBOOL trusted = CK_FALSE;
CK_BBOOL distrust = CK_FALSE;
CK_ATTRIBUTE trust_attrs[] = {
{ CKA_TRUSTED, &trusted, sizeof (trusted) },
{ CKA_X_DISTRUSTED, &distrust, sizeof (distrust) },
{ CKA_INVALID },
};
CK_ATTRIBUTE *attrs;
p11_dict *trust = NULL;
p11_dict *reject = NULL;
p11_dictiter iter;
void *key;
int start;
int end;
int ret;
int num;
/*
* This will load an empty list if there is no OPTIONAL trust field.
* OpenSSL assumes that for a TRUSTED CERTIFICATE a missing trust field
* is identical to untrusted for all purposes.
*
* This is different from ExtendedKeyUsage, where a missing certificate
* extension means that it is trusted for all purposes.
*/
trust = load_seq_of_oid_str (aux, "trust");
ret = asn1_number_of_elements (aux, "reject", &num);
return_val_if_fail (ret == ASN1_SUCCESS || ret == ASN1_ELEMENT_NOT_FOUND, NULL);
if (ret == ASN1_SUCCESS)
reject = load_seq_of_oid_str (aux, "reject");
/* Remove all rejected oids from the trust set */
if (trust && reject) {
p11_dict_iterate (reject, &iter);
while (p11_dict_next (&iter, &key, NULL))
p11_dict_remove (trust, key);
}
/*
* The trust field (or lack of it) becomes a standard ExtKeyUsageSyntax.
*
* critical: require that this is enforced
*/
if (trust) {
attrs = attached_eku_attrs (parser, public_key_info,
P11_OID_EXTENDED_KEY_USAGE_STR,
P11_OID_EXTENDED_KEY_USAGE,
true, trust);
return_val_if_fail (attrs != NULL, NULL);
sink_object (parser, attrs);
}
/*
* For the reject field we use a custom defined extension. We track this
* for completeness, although the above ExtendedKeyUsage extension handles
* this data fine. See oid.h for more details. It uses ExtKeyUsageSyntax structure.
*
* non-critical: non-standard, and also covered by trusts
*/
if (reject && p11_dict_size (reject) > 0) {
attrs = attached_eku_attrs (parser, public_key_info,
P11_OID_OPENSSL_REJECT_STR,
P11_OID_OPENSSL_REJECT,
false, reject);
return_val_if_fail (attrs != NULL, NULL);
sink_object (parser, attrs);
}
/*
* OpenSSL model blacklists as anchors with all purposes being removed/rejected,
* we account for that here. If there is an ExtendedKeyUsage without any
* useful purposes, then treat like a blacklist.
*/
if (trust && p11_dict_size (trust) == 0) {
trusted = CK_FALSE;
distrust = CK_TRUE;
/*
* Otherwise a 'TRUSTED CERTIFICATE' in an input directory is enough to
* mark this as a trusted certificate.
*/
} else if (trust && p11_dict_size (trust) > 0) {
trusted = CK_TRUE;
distrust = CK_FALSE;
}
/*
* OpenSSL model blacklists as anchors with all purposes being removed/rejected,
* we account for that here. If there is an ExtendedKeyUsage without any
* useful purposes, then treat like a blacklist.
*/
cert = p11_attrs_merge (cert, p11_attrs_dup (trust_attrs), true);
return_val_if_fail (cert != NULL, NULL);
p11_dict_free (trust);
p11_dict_free (reject);
/*
* For the keyid field we use the SubjectKeyIdentifier extension. It
* is already in the correct form, an OCTET STRING.
*
* non-critical: as recommended in RFC 5280
*/
ret = asn1_der_decoding_startEnd (aux, aux_der, aux_len, "keyid", &start, &end);
return_val_if_fail (ret == ASN1_SUCCESS || ret == ASN1_ELEMENT_NOT_FOUND, NULL);
if (ret == ASN1_SUCCESS) {
attrs = extension_attrs (parser, public_key_info,
P11_OID_SUBJECT_KEY_IDENTIFIER_STR,
P11_OID_SUBJECT_KEY_IDENTIFIER,
false, aux_der + start, (end - start) + 1);
return_val_if_fail (attrs != NULL, NULL);
sink_object (parser, attrs);
}
return cert;
}
static int
parse_openssl_trusted_certificate (p11_parser *parser,
const unsigned char *data,
size_t length)
{
char message[ASN1_MAX_ERROR_DESCRIPTION_SIZE];
CK_ATTRIBUTE *attrs;
CK_ATTRIBUTE public_key_info = { CKA_PUBLIC_KEY_INFO };
CK_ATTRIBUTE *value;
char *label = NULL;
node_asn *cert;
node_asn *aux = NULL;
ssize_t cert_len;
size_t len;
int start;
int end;
int ret;
/*
* This OpenSSL format is weird. It's just two DER structures
* placed end to end without any wrapping SEQ. So calculate the
* length of the first DER TLV we see and try to parse that as
* the X.509 certificate.
*/
cert_len = p11_asn1_tlv_length (data, length);
if (cert_len <= 0)
return P11_PARSE_UNRECOGNIZED;
cert = p11_asn1_decode (parser->asn1_defs, "PKIX1.Certificate", data, cert_len, message);
if (cert == NULL)
return P11_PARSE_UNRECOGNIZED;
/* OpenSSL sometimes outputs TRUSTED CERTIFICATE format without the CertAux supplement */
if (cert_len < length) {
aux = p11_asn1_decode (parser->asn1_defs, "OPENSSL.CertAux", data + cert_len,
length - cert_len, message);
if (aux == NULL) {
asn1_delete_structure (&cert);
return P11_PARSE_UNRECOGNIZED;
}
}
attrs = certificate_attrs (parser, data, cert_len);
return_val_if_fail (attrs != NULL, P11_PARSE_FAILURE);
/* Cache the parsed certificate ASN.1 for later use by the builder */
value = p11_attrs_find_valid (attrs, CKA_VALUE);
return_val_if_fail (value != NULL, P11_PARSE_FAILURE);
/* Pull out the subject public key info */
ret = asn1_der_decoding_startEnd (cert, data, cert_len,
"tbsCertificate.subjectPublicKeyInfo", &start, &end);
return_val_if_fail (ret == ASN1_SUCCESS, P11_PARSE_FAILURE);
public_key_info.pValue = (char *)data + start;
public_key_info.ulValueLen = (end - start) + 1;
p11_asn1_cache_take (parser->asn1_cache, cert, "PKIX1.Certificate",
value->pValue, value->ulValueLen);
/* Pull the label out of the CertAux */
if (aux) {
len = 0;
label = p11_asn1_read (aux, "alias", &len);
if (label != NULL) {
attrs = p11_attrs_take (attrs, CKA_LABEL, label, strlen (label));
return_val_if_fail (attrs != NULL, P11_PARSE_FAILURE);
}
attrs = build_openssl_extensions (parser, attrs, &public_key_info, aux,
data + cert_len, length - cert_len);
return_val_if_fail (attrs != NULL, P11_PARSE_FAILURE);
}
sink_object (parser, attrs);
asn1_delete_structure (&aux);
return P11_PARSE_SUCCESS;
}
static void
on_pem_block (const char *type,
const unsigned char *contents,
size_t length,
void *user_data)
{
p11_parser *parser = user_data;
int ret;
if (strcmp (type, "CERTIFICATE") == 0) {
ret = p11_parser_format_x509 (parser, contents, length);
} else if (strcmp (type, "TRUSTED CERTIFICATE") == 0) {
ret = parse_openssl_trusted_certificate (parser, contents, length);
} else {
p11_debug ("Saw unsupported or unrecognized PEM block of type %s", type);
ret = P11_PARSE_SUCCESS;
}
if (ret != P11_PARSE_SUCCESS)
p11_message ("Couldn't parse PEM block of type %s", type);
}
int
p11_parser_format_pem (p11_parser *parser,
const unsigned char *data,
size_t length)
{
int num;
num = p11_pem_parse ((const char *)data, length, on_pem_block, parser);
if (num == 0)
return P11_PARSE_UNRECOGNIZED;
return P11_PARSE_SUCCESS;
}
int
p11_parser_format_persist (p11_parser *parser,
const unsigned char *data,
size_t length)
{
CK_BBOOL modifiablev = CK_TRUE;
CK_ATTRIBUTE *attrs;
p11_array *objects;
bool ret;
int i;
CK_ATTRIBUTE modifiable = { CKA_MODIFIABLE, &modifiablev, sizeof (modifiablev) };
if (!p11_persist_magic (data, length))
return P11_PARSE_UNRECOGNIZED;
if (!parser->persist) {
parser->persist = p11_persist_new ();
return_val_if_fail (parser->persist != NULL, P11_PARSE_UNRECOGNIZED);
}
objects = p11_array_new (NULL);
return_val_if_fail (objects != NULL, P11_PARSE_FAILURE);
ret = p11_persist_read (parser->persist, parser->basename, data, length, objects);
if (ret) {
if (!p11_persist_is_generated (data, length))
modifiablev = CK_FALSE;
for (i = 0; i < objects->num; i++) {
attrs = p11_attrs_build (objects->elem[i], &modifiable, NULL);
sink_object (parser, attrs);
}
}
p11_array_free (objects);
return ret ? P11_PARSE_SUCCESS : P11_PARSE_UNRECOGNIZED;
}
p11_parser *
p11_parser_new (p11_asn1_cache *asn1_cache)
{
p11_parser parser = { 0, };
if (asn1_cache == NULL) {
parser.asn1_owned = true;
parser.asn1_defs = p11_asn1_defs_load ();
} else {
parser.asn1_defs = p11_asn1_cache_defs (asn1_cache);
parser.asn1_cache = asn1_cache;
parser.asn1_owned = false;
}
parser.parsed = p11_array_new (p11_attrs_free);
return_val_if_fail (parser.parsed != NULL, NULL);
return memdup (&parser, sizeof (parser));
}
void
p11_parser_free (p11_parser *parser)
{
return_if_fail (parser != NULL);
p11_persist_free (parser->persist);
p11_array_free (parser->parsed);
p11_array_free (parser->formats);
if (parser->asn1_owned)
p11_dict_free (parser->asn1_defs);
free (parser);
}
p11_array *
p11_parser_parsed (p11_parser *parser)
{
return_val_if_fail (parser != NULL, NULL);
return parser->parsed;
}
void
p11_parser_formats (p11_parser *parser,
...)
{
p11_array *formats;
parser_func func;
va_list va;
formats = p11_array_new (NULL);
return_if_fail (formats != NULL);
va_start (va, parser);
for (;;) {
func = va_arg (va, parser_func);
if (func == NULL)
break;
if (!p11_array_push (formats, func)) {
va_end (va);
return_if_reached ();
}
}
va_end (va);
p11_array_free (parser->formats);
parser->formats = formats;
}
int
p11_parse_memory (p11_parser *parser,
const char *filename,
int flags,
const unsigned char *data,
size_t length)
{
int ret = P11_PARSE_UNRECOGNIZED;
char *base;
int i;
return_val_if_fail (parser != NULL, P11_PARSE_FAILURE);
return_val_if_fail (filename != NULL, P11_PARSE_FAILURE);
return_val_if_fail (parser->formats != NULL, P11_PARSE_FAILURE);
p11_array_clear (parser->parsed);
base = p11_path_base (filename);
parser->basename = base;
parser->flags = flags;
for (i = 0; ret == P11_PARSE_UNRECOGNIZED && i < parser->formats->num; i++)
ret = ((parser_func)parser->formats->elem[i]) (parser, data, length);
p11_asn1_cache_flush (parser->asn1_cache);
free (base);
parser->basename = NULL;
parser->flags = 0;
return ret;
}
int
p11_parse_file (p11_parser *parser,
const char *filename,
struct stat *sb,
int flags)
{
p11_mmap *map;
void *data;
size_t size;
int ret;
return_val_if_fail (parser != NULL, P11_PARSE_FAILURE);
return_val_if_fail (filename != NULL, P11_PARSE_FAILURE);
map = p11_mmap_open (filename, sb, &data, &size);
if (map == NULL) {
p11_message_err (errno, "couldn't open and map file: %s", filename);
return P11_PARSE_FAILURE;
}
ret = p11_parse_memory (parser, filename, flags, data, size);
p11_mmap_close (map);
return ret;
}