sbverify: Add certificate chain verification
Add an option (--cert <file>) to specify a root certificate (or certificates) to use as a trusted CA. Verification can be disabled with --no-verify. Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
This commit is contained in:
parent
e404a4d412
commit
e3d6afbd61
1 changed files with 100 additions and 6 deletions
106
sbverify.c
106
sbverify.c
|
@ -16,10 +16,13 @@
|
|||
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
|
||||
* USA.
|
||||
*/
|
||||
#define _GNU_SOURCE
|
||||
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
|
||||
#include <getopt.h>
|
||||
|
||||
#include <ccan/talloc/talloc.h>
|
||||
|
||||
#include "image.h"
|
||||
|
@ -29,31 +32,118 @@
|
|||
#include <openssl/bio.h>
|
||||
#include <openssl/evp.h>
|
||||
#include <openssl/pkcs7.h>
|
||||
#include <openssl/pem.h>
|
||||
#include <openssl/x509v3.h>
|
||||
|
||||
enum verify_status {
|
||||
VERIFY_FAIL = 0,
|
||||
VERIFY_OK = 1,
|
||||
};
|
||||
|
||||
static struct option options[] = {
|
||||
{ "cert", required_argument, NULL, 'c' },
|
||||
{ "no-verify", no_argument, NULL, 'n' },
|
||||
{ NULL, 0, NULL, 0 },
|
||||
};
|
||||
|
||||
static void usage(const char *progname)
|
||||
{
|
||||
fprintf(stderr,
|
||||
"usage: %s --cert <certfile> <efi-boot-image>\n"
|
||||
"options:\n"
|
||||
"\t--cert <certfile> certificate (x509 certificate)\n"
|
||||
"\t--no-verify don't perform certificate verification\n",
|
||||
progname);
|
||||
}
|
||||
|
||||
int load_cert(X509_STORE *certs, const char *filename)
|
||||
{
|
||||
X509 *cert;
|
||||
BIO *bio;
|
||||
|
||||
bio = NULL;
|
||||
cert = NULL;
|
||||
|
||||
bio = BIO_new_file(filename, "r");
|
||||
if (!bio) {
|
||||
fprintf(stderr, "Couldn't open file %s\n", filename);
|
||||
goto err;
|
||||
}
|
||||
|
||||
cert = PEM_read_bio_X509(bio, NULL, NULL, NULL);
|
||||
if (!cert) {
|
||||
fprintf(stderr, "Couldn't read certificate file %s\n",
|
||||
filename);
|
||||
goto err;
|
||||
}
|
||||
|
||||
X509_STORE_add_cert(certs, cert);
|
||||
return 0;
|
||||
|
||||
err:
|
||||
ERR_print_errors_fp(stderr);
|
||||
if (cert)
|
||||
X509_free(cert);
|
||||
if (bio)
|
||||
BIO_free(bio);
|
||||
return -1;
|
||||
}
|
||||
|
||||
static int x509_verify_cb(int status, X509_STORE_CTX *ctx)
|
||||
{
|
||||
int err = X509_STORE_CTX_get_error(ctx);
|
||||
|
||||
/* also accept code-signing keys */
|
||||
if (err == X509_V_ERR_INVALID_PURPOSE
|
||||
&& ctx->cert->ex_xkusage == XKU_CODE_SIGN)
|
||||
status = 1;
|
||||
|
||||
return status;
|
||||
}
|
||||
|
||||
int main(int argc, char **argv)
|
||||
{
|
||||
struct cert_table_header *header;
|
||||
enum verify_status status;
|
||||
int rc, c, flags, verify;
|
||||
struct image *image;
|
||||
const uint8_t *buf;
|
||||
X509_STORE *certs;
|
||||
struct idc *idc;
|
||||
int rc;
|
||||
BIO *idcbio;
|
||||
PKCS7 *p7;
|
||||
|
||||
status = VERIFY_FAIL;
|
||||
certs = X509_STORE_new();
|
||||
verify = 1;
|
||||
|
||||
if (argc != 2) {
|
||||
fprintf(stderr, "usage: %s <boot-image>\n", argv[0]);
|
||||
ERR_load_crypto_strings();
|
||||
|
||||
for (;;) {
|
||||
int idx;
|
||||
c = getopt_long(argc, argv, "c:n", options, &idx);
|
||||
if (c == -1)
|
||||
break;
|
||||
|
||||
switch (c) {
|
||||
case 'c':
|
||||
rc = load_cert(certs, optarg);
|
||||
if (rc)
|
||||
return EXIT_FAILURE;
|
||||
break;
|
||||
case 'n':
|
||||
verify = 0;
|
||||
break;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
if (argc != optind + 1) {
|
||||
usage(argv[0]);
|
||||
return EXIT_FAILURE;
|
||||
}
|
||||
|
||||
image = image_load(argv[1]);
|
||||
image = image_load(argv[optind]);
|
||||
image_pecoff_parse(image);
|
||||
image_find_regions(image);
|
||||
|
||||
|
@ -79,8 +169,12 @@ int main(int argc, char **argv)
|
|||
if (rc)
|
||||
goto out;
|
||||
|
||||
rc = PKCS7_verify(p7, NULL, NULL, idcbio, NULL,
|
||||
PKCS7_BINARY | PKCS7_NOVERIFY);
|
||||
flags = PKCS7_BINARY;
|
||||
if (!verify)
|
||||
flags |= PKCS7_NOVERIFY;
|
||||
|
||||
X509_STORE_set_verify_cb_func(certs, x509_verify_cb);
|
||||
rc = PKCS7_verify(p7, NULL, certs, idcbio, NULL, flags);
|
||||
if (!rc) {
|
||||
printf("PKCS7 verification failed\n");
|
||||
ERR_print_errors_fp(stderr);
|
||||
|
|
Loading…
Reference in a new issue