modsign: Make sign-file determine the format of the X.509 cert
Make sign-file determine the format of the X.509 certificate by reading the
first two bytes and seeing if the first byte is 0x30 and the second
0x81-0x84. If this is the case, assume it's DER encoded, otherwise assume
it to be PEM encoded.
Without this, it gets awkward to deal with the error messages from
d2i_X509_bio() when we want to call BIO_reset() and then PEM_read_bio() in
case the certificate was PEM encoded rather than X.509 encoded.
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Ben Hutchings <ben@decadent.org.uk>
cc: David Woodhouse <dwmw2@infradead.org>
cc: Juerg Haefliger <juerg.haefliger@hpe.com>
cc: Ben Hutchings <ben@decadent.org.uk>
diff --git a/scripts/sign-file.c b/scripts/sign-file.c
index d912d5a..53af6dc 100755
--- a/scripts/sign-file.c
+++ b/scripts/sign-file.c
@@ -1,6 +1,6 @@
/* Sign a module file using the given key.
*
- * Copyright © 2014-2015 Red Hat, Inc. All Rights Reserved.
+ * Copyright © 2014-2016 Red Hat, Inc. All Rights Reserved.
* Copyright © 2015 Intel Corporation.
* Copyright © 2016 Hewlett Packard Enterprise Development LP
*
@@ -167,19 +167,37 @@
static X509 *read_x509(const char *x509_name)
{
+ unsigned char buf[2];
X509 *x509;
BIO *b;
+ int n;
b = BIO_new_file(x509_name, "rb");
ERR(!b, "%s", x509_name);
- x509 = d2i_X509_bio(b, NULL); /* Binary encoded X.509 */
- if (!x509) {
- ERR(BIO_reset(b) != 1, "%s", x509_name);
- x509 = PEM_read_bio_X509(b, NULL, NULL,
- NULL); /* PEM encoded X.509 */
- if (x509)
- drain_openssl_errors();
+
+ /* Look at the first two bytes of the file to determine the encoding */
+ n = BIO_read(b, buf, 2);
+ if (n != 2) {
+ if (BIO_should_retry(b)) {
+ fprintf(stderr, "%s: Read wanted retry\n", x509_name);
+ exit(1);
+ }
+ if (n >= 0) {
+ fprintf(stderr, "%s: Short read\n", x509_name);
+ exit(1);
+ }
+ ERR(1, "%s", x509_name);
}
+
+ ERR(BIO_reset(b) != 0, "%s", x509_name);
+
+ if (buf[0] == 0x30 && buf[1] >= 0x81 && buf[1] <= 0x84)
+ /* Assume raw DER encoded X.509 */
+ x509 = d2i_X509_bio(b, NULL);
+ else
+ /* Assume PEM encoded X.509 */
+ x509 = PEM_read_bio_X509(b, NULL, NULL, NULL);
+
BIO_free(b);
ERR(!x509, "%s", x509_name);