modsign: Allow password to be specified for signing key

We don't want this in the Kconfig since it might then get exposed in
/proc/config.gz. So make it a parameter to Kbuild instead. This also
means we don't have to jump through hoops to strip quotes from it, as
we would if it was a config option.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This commit is contained in:
David Woodhouse 2015-07-20 21:16:28 +01:00 committed by David Howells
parent caf6fe91dd
commit af1eb29132
3 changed files with 34 additions and 1 deletions

View File

@ -174,6 +174,11 @@ The output directory is often set using "O=..." on the commandline.
The value can be overridden in which case the default value is ignored.
KBUILD_SIGN_PIN
--------------------------------------------------
This variable allows a passphrase or PIN to be passed to the sign-file
utility when signing kernel modules, if the private key requires such.
KBUILD_MODPOST_WARN
--------------------------------------------------
KBUILD_MODPOST_WARN can be set to avoid errors in case of undefined

View File

@ -194,6 +194,9 @@ The hash algorithm used does not have to match the one configured, but if it
doesn't, you should make sure that hash algorithm is either built into the
kernel or can be loaded without requiring itself.
If the private key requires a passphrase or PIN, it can be provided in the
$KBUILD_SIGN_PIN environment variable.
============================
SIGNED MODULES AND STRIPPING

View File

@ -80,6 +80,27 @@ static void drain_openssl_errors(void)
} \
} while(0)
static const char *key_pass;
static int pem_pw_cb(char *buf, int len, int w, void *v)
{
int pwlen;
if (!key_pass)
return -1;
pwlen = strlen(key_pass);
if (pwlen >= len)
return -1;
strcpy(buf, key_pass);
/* If it's wrong, don't keep trying it. */
key_pass = NULL;
return pwlen;
}
int main(int argc, char **argv)
{
struct module_signature sig_info = { .id_type = PKEY_ID_PKCS7 };
@ -96,9 +117,12 @@ int main(int argc, char **argv)
BIO *b, *bd = NULL, *bm;
int opt, n;
OpenSSL_add_all_algorithms();
ERR_load_crypto_strings();
ERR_clear_error();
key_pass = getenv("KBUILD_SIGN_PIN");
do {
opt = getopt(argc, argv, "dp");
switch (opt) {
@ -132,7 +156,8 @@ int main(int argc, char **argv)
*/
b = BIO_new_file(private_key_name, "rb");
ERR(!b, "%s", private_key_name);
private_key = PEM_read_bio_PrivateKey(b, NULL, NULL, NULL);
private_key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb, NULL);
ERR(!private_key, "%s", private_key_name);
BIO_free(b);
b = BIO_new_file(x509_name, "rb");