forked from mirrors/linux
MODSIGN: Use PKCS#7 messages as module signatures
Move to using PKCS#7 messages as module signatures because:
(1) We have to be able to support the use of X.509 certificates that don't
have a subjKeyId set. We're currently relying on this to look up the
X.509 certificate in the trusted keyring list.
(2) PKCS#7 message signed information blocks have a field that supplies the
data required to match with the X.509 certificate that signed it.
(3) The PKCS#7 certificate carries fields that specify the digest algorithm
used to generate the signature in a standardised way and the X.509
certificates specify the public key algorithm in a standardised way - so
we don't need our own methods of specifying these.
(4) We now have PKCS#7 message support in the kernel for signed kexec purposes
and we can make use of this.
To make this work, the old sign-file script has been replaced with a program
that needs compiling in a previous patch. The rules to build it are added
here.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Vivek Goyal <vgoyal@redhat.com>
This commit is contained in:
David Howells
parent
bc1c373dd2
commit
3f1e1bea34
5 changed files with 46 additions and 596 deletions
2
Makefile
2
Makefile
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@ -873,7 +873,7 @@ ifdef CONFIG_MODULE_SIG_ALL
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MODSECKEY = ./signing_key.priv
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MODSECKEY = ./signing_key.priv
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MODPUBKEY = ./signing_key.x509
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MODPUBKEY = ./signing_key.x509
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export MODPUBKEY
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export MODPUBKEY
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mod_sign_cmd = perl $(srctree)/scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODSECKEY) $(MODPUBKEY)
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mod_sign_cmd = scripts/sign-file $(CONFIG_MODULE_SIG_HASH) $(MODSECKEY) $(MODPUBKEY)
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else
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else
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mod_sign_cmd = true
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mod_sign_cmd = true
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endif
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endif
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@ -1869,6 +1869,7 @@ config MODULE_SIG
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select ASN1
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select ASN1
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select OID_REGISTRY
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select OID_REGISTRY
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select X509_CERTIFICATE_PARSER
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select X509_CERTIFICATE_PARSER
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select PKCS7_MESSAGE_PARSER
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help
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help
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Check modules for valid signatures upon load: the signature
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Check modules for valid signatures upon load: the signature
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is simply appended to the module. For more information see
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is simply appended to the module. For more information see
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@ -11,10 +11,9 @@
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#include <linux/kernel.h>
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#include <linux/kernel.h>
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#include <linux/err.h>
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#include <linux/err.h>
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#include <crypto/public_key.h>
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#include <crypto/hash.h>
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#include <keys/asymmetric-type.h>
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#include <keys/system_keyring.h>
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#include <keys/system_keyring.h>
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#include <crypto/public_key.h>
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#include <crypto/pkcs7.h>
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#include "module-internal.h"
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#include "module-internal.h"
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/*
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/*
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@ -28,157 +27,53 @@
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* - Information block
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* - Information block
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*/
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*/
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struct module_signature {
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struct module_signature {
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u8 algo; /* Public-key crypto algorithm [enum pkey_algo] */
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u8 algo; /* Public-key crypto algorithm [0] */
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u8 hash; /* Digest algorithm [enum hash_algo] */
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u8 hash; /* Digest algorithm [0] */
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u8 id_type; /* Key identifier type [enum pkey_id_type] */
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u8 id_type; /* Key identifier type [PKEY_ID_PKCS7] */
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u8 signer_len; /* Length of signer's name */
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u8 signer_len; /* Length of signer's name [0] */
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u8 key_id_len; /* Length of key identifier */
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u8 key_id_len; /* Length of key identifier [0] */
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u8 __pad[3];
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u8 __pad[3];
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__be32 sig_len; /* Length of signature data */
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__be32 sig_len; /* Length of signature data */
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};
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};
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/*
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/*
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* Digest the module contents.
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* Verify a PKCS#7-based signature on a module.
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*/
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*/
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static struct public_key_signature *mod_make_digest(enum hash_algo hash,
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static int mod_verify_pkcs7(const void *mod, unsigned long modlen,
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const void *mod,
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const void *raw_pkcs7, size_t pkcs7_len)
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unsigned long modlen)
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{
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{
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struct public_key_signature *pks;
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struct pkcs7_message *pkcs7;
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struct crypto_shash *tfm;
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bool trusted;
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struct shash_desc *desc;
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size_t digest_size, desc_size;
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int ret;
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int ret;
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pr_devel("==>%s()\n", __func__);
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pkcs7 = pkcs7_parse_message(raw_pkcs7, pkcs7_len);
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if (IS_ERR(pkcs7))
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return PTR_ERR(pkcs7);
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/* Allocate the hashing algorithm we're going to need and find out how
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/* The data should be detached - so we need to supply it. */
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* big the hash operational data will be.
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if (pkcs7_supply_detached_data(pkcs7, mod, modlen) < 0) {
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*/
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pr_err("PKCS#7 signature with non-detached data\n");
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tfm = crypto_alloc_shash(hash_algo_name[hash], 0, 0);
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ret = -EBADMSG;
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if (IS_ERR(tfm))
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goto error;
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return (PTR_ERR(tfm) == -ENOENT) ? ERR_PTR(-ENOPKG) : ERR_CAST(tfm);
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}
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desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
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ret = pkcs7_verify(pkcs7);
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digest_size = crypto_shash_digestsize(tfm);
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/* We allocate the hash operational data storage on the end of our
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* context data and the digest output buffer on the end of that.
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*/
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ret = -ENOMEM;
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pks = kzalloc(digest_size + sizeof(*pks) + desc_size, GFP_KERNEL);
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if (!pks)
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goto error_no_pks;
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pks->pkey_hash_algo = hash;
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pks->digest = (u8 *)pks + sizeof(*pks) + desc_size;
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pks->digest_size = digest_size;
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desc = (void *)pks + sizeof(*pks);
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desc->tfm = tfm;
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desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
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ret = crypto_shash_init(desc);
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if (ret < 0)
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if (ret < 0)
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goto error;
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goto error;
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ret = crypto_shash_finup(desc, mod, modlen, pks->digest);
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ret = pkcs7_validate_trust(pkcs7, system_trusted_keyring, &trusted);
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if (ret < 0)
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if (ret < 0)
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goto error;
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goto error;
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crypto_free_shash(tfm);
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if (!trusted) {
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pr_devel("<==%s() = ok\n", __func__);
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pr_err("PKCS#7 signature not signed with a trusted key\n");
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return pks;
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ret = -ENOKEY;
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}
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error:
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error:
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kfree(pks);
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pkcs7_free_message(pkcs7);
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error_no_pks:
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crypto_free_shash(tfm);
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pr_devel("<==%s() = %d\n", __func__, ret);
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pr_devel("<==%s() = %d\n", __func__, ret);
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return ERR_PTR(ret);
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return ret;
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}
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/*
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* Extract an MPI array from the signature data. This represents the actual
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* signature. Each raw MPI is prefaced by a BE 2-byte value indicating the
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* size of the MPI in bytes.
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*
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* RSA signatures only have one MPI, so currently we only read one.
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*/
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static int mod_extract_mpi_array(struct public_key_signature *pks,
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const void *data, size_t len)
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{
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size_t nbytes;
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MPI mpi;
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if (len < 3)
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return -EBADMSG;
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nbytes = ((const u8 *)data)[0] << 8 | ((const u8 *)data)[1];
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data += 2;
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len -= 2;
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if (len != nbytes)
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return -EBADMSG;
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mpi = mpi_read_raw_data(data, nbytes);
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if (!mpi)
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return -ENOMEM;
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pks->mpi[0] = mpi;
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pks->nr_mpi = 1;
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return 0;
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}
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/*
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* Request an asymmetric key.
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*/
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static struct key *request_asymmetric_key(const char *signer, size_t signer_len,
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const u8 *key_id, size_t key_id_len)
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{
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key_ref_t key;
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size_t i;
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char *id, *q;
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pr_devel("==>%s(,%zu,,%zu)\n", __func__, signer_len, key_id_len);
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/* Construct an identifier. */
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id = kmalloc(signer_len + 2 + key_id_len * 2 + 1, GFP_KERNEL);
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if (!id)
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return ERR_PTR(-ENOKEY);
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memcpy(id, signer, signer_len);
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q = id + signer_len;
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*q++ = ':';
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*q++ = ' ';
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for (i = 0; i < key_id_len; i++) {
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*q++ = hex_asc[*key_id >> 4];
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*q++ = hex_asc[*key_id++ & 0x0f];
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}
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*q = 0;
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pr_debug("Look up: \"%s\"\n", id);
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key = keyring_search(make_key_ref(system_trusted_keyring, 1),
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&key_type_asymmetric, id);
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if (IS_ERR(key))
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pr_warn("Request for unknown module key '%s' err %ld\n",
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id, PTR_ERR(key));
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kfree(id);
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if (IS_ERR(key)) {
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switch (PTR_ERR(key)) {
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/* Hide some search errors */
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case -EACCES:
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case -ENOTDIR:
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case -EAGAIN:
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return ERR_PTR(-ENOKEY);
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default:
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return ERR_CAST(key);
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}
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}
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pr_devel("<==%s() = 0 [%x]\n", __func__, key_serial(key_ref_to_ptr(key)));
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return key_ref_to_ptr(key);
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}
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}
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/*
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/*
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@ -186,12 +81,8 @@ static struct key *request_asymmetric_key(const char *signer, size_t signer_len,
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*/
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*/
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int mod_verify_sig(const void *mod, unsigned long *_modlen)
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int mod_verify_sig(const void *mod, unsigned long *_modlen)
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{
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{
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struct public_key_signature *pks;
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struct module_signature ms;
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struct module_signature ms;
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struct key *key;
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const void *sig;
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size_t modlen = *_modlen, sig_len;
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size_t modlen = *_modlen, sig_len;
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int ret;
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pr_devel("==>%s(,%zu)\n", __func__, modlen);
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pr_devel("==>%s(,%zu)\n", __func__, modlen);
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@ -205,46 +96,23 @@ int mod_verify_sig(const void *mod, unsigned long *_modlen)
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if (sig_len >= modlen)
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if (sig_len >= modlen)
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return -EBADMSG;
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return -EBADMSG;
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modlen -= sig_len;
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modlen -= sig_len;
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if ((size_t)ms.signer_len + ms.key_id_len >= modlen)
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return -EBADMSG;
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modlen -= (size_t)ms.signer_len + ms.key_id_len;
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*_modlen = modlen;
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*_modlen = modlen;
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sig = mod + modlen;
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/* For the moment, only support RSA and X.509 identifiers */
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if (ms.id_type != PKEY_ID_PKCS7) {
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if (ms.algo != PKEY_ALGO_RSA ||
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pr_err("Module is not signed with expected PKCS#7 message\n");
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ms.id_type != PKEY_ID_X509)
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return -ENOPKG;
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return -ENOPKG;
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if (ms.hash >= PKEY_HASH__LAST ||
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!hash_algo_name[ms.hash])
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return -ENOPKG;
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key = request_asymmetric_key(sig, ms.signer_len,
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sig + ms.signer_len, ms.key_id_len);
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if (IS_ERR(key))
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return PTR_ERR(key);
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pks = mod_make_digest(ms.hash, mod, modlen);
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if (IS_ERR(pks)) {
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ret = PTR_ERR(pks);
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goto error_put_key;
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}
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}
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ret = mod_extract_mpi_array(pks, sig + ms.signer_len + ms.key_id_len,
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if (ms.algo != 0 ||
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sig_len);
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ms.hash != 0 ||
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if (ret < 0)
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ms.signer_len != 0 ||
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goto error_free_pks;
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ms.key_id_len != 0 ||
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ms.__pad[0] != 0 ||
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ms.__pad[1] != 0 ||
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ms.__pad[2] != 0) {
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pr_err("PKCS#7 signature info has unexpected non-zero params\n");
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return -EBADMSG;
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}
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ret = verify_signature(key, pks);
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return mod_verify_pkcs7(mod, modlen, mod + modlen, sig_len);
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pr_devel("verify_signature() = %d\n", ret);
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error_free_pks:
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mpi_free(pks->rsa.s);
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kfree(pks);
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error_put_key:
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key_put(key);
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pr_devel("<==%s() = %d\n", __func__, ret);
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return ret;
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}
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}
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@ -16,9 +16,11 @@ hostprogs-$(CONFIG_VT) += conmakehash
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hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount
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hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount
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hostprogs-$(CONFIG_BUILDTIME_EXTABLE_SORT) += sortextable
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hostprogs-$(CONFIG_BUILDTIME_EXTABLE_SORT) += sortextable
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hostprogs-$(CONFIG_ASN1) += asn1_compiler
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hostprogs-$(CONFIG_ASN1) += asn1_compiler
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hostprogs-$(CONFIG_MODULE_SIG) += sign-file
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HOSTCFLAGS_sortextable.o = -I$(srctree)/tools/include
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HOSTCFLAGS_sortextable.o = -I$(srctree)/tools/include
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HOSTCFLAGS_asn1_compiler.o = -I$(srctree)/include
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HOSTCFLAGS_asn1_compiler.o = -I$(srctree)/include
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HOSTLOADLIBES_sign-file = -lcrypto
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always := $(hostprogs-y) $(hostprogs-m)
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always := $(hostprogs-y) $(hostprogs-m)
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@ -1,421 +0,0 @@
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#!/usr/bin/perl -w
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#
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# Sign a module file using the given key.
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#
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my $USAGE =
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"Usage: scripts/sign-file [-v] <hash algo> <key> <x509> <module> [<dest>]\n" .
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" scripts/sign-file [-v] -s <raw sig> <hash algo> <x509> <module> [<dest>]\n";
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use strict;
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use FileHandle;
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use IPC::Open2;
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use Getopt::Std;
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my %opts;
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getopts('vs:', \%opts) or die $USAGE;
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my $verbose = $opts{'v'};
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my $signature_file = $opts{'s'};
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die $USAGE if ($#ARGV > 4);
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die $USAGE if (!$signature_file && $#ARGV < 3 || $signature_file && $#ARGV < 2);
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my $dgst = shift @ARGV;
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my $private_key;
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if (!$signature_file) {
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$private_key = shift @ARGV;
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}
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my $x509 = shift @ARGV;
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my $module = shift @ARGV;
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my ($dest, $keep_orig);
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if (@ARGV) {
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$dest = $ARGV[0];
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$keep_orig = 1;
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} else {
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$dest = $module . "~";
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}
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die "Can't read private key\n" if (!$signature_file && !-r $private_key);
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die "Can't read signature file\n" if ($signature_file && !-r $signature_file);
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die "Can't read X.509 certificate\n" unless (-r $x509);
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die "Can't read module\n" unless (-r $module);
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#
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||||||
# Function to read the contents of a file into a variable.
|
|
||||||
#
|
|
||||||
sub read_file($)
|
|
||||||
{
|
|
||||||
my ($file) = @_;
|
|
||||||
my $contents;
|
|
||||||
my $len;
|
|
||||||
|
|
||||||
open(FD, "<$file") || die $file;
|
|
||||||
binmode FD;
|
|
||||||
my @st = stat(FD);
|
|
||||||
die $file if (!@st);
|
|
||||||
$len = read(FD, $contents, $st[7]) || die $file;
|
|
||||||
close(FD) || die $file;
|
|
||||||
die "$file: Wanted length ", $st[7], ", got ", $len, "\n"
|
|
||||||
if ($len != $st[7]);
|
|
||||||
return $contents;
|
|
||||||
}
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# First of all, we have to parse the X.509 certificate to find certain details
|
|
||||||
# about it.
|
|
||||||
#
|
|
||||||
# We read the DER-encoded X509 certificate and parse it to extract the Subject
|
|
||||||
# name and Subject Key Identifier. Theis provides the data we need to build
|
|
||||||
# the certificate identifier.
|
|
||||||
#
|
|
||||||
# The signer's name part of the identifier is fabricated from the commonName,
|
|
||||||
# the organizationName or the emailAddress components of the X.509 subject
|
|
||||||
# name.
|
|
||||||
#
|
|
||||||
# The subject key ID is used to select which of that signer's certificates
|
|
||||||
# we're intending to use to sign the module.
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
my $x509_certificate = read_file($x509);
|
|
||||||
|
|
||||||
my $UNIV = 0 << 6;
|
|
||||||
my $APPL = 1 << 6;
|
|
||||||
my $CONT = 2 << 6;
|
|
||||||
my $PRIV = 3 << 6;
|
|
||||||
|
|
||||||
my $CONS = 0x20;
|
|
||||||
|
|
||||||
my $BOOLEAN = 0x01;
|
|
||||||
my $INTEGER = 0x02;
|
|
||||||
my $BIT_STRING = 0x03;
|
|
||||||
my $OCTET_STRING = 0x04;
|
|
||||||
my $NULL = 0x05;
|
|
||||||
my $OBJ_ID = 0x06;
|
|
||||||
my $UTF8String = 0x0c;
|
|
||||||
my $SEQUENCE = 0x10;
|
|
||||||
my $SET = 0x11;
|
|
||||||
my $UTCTime = 0x17;
|
|
||||||
my $GeneralizedTime = 0x18;
|
|
||||||
|
|
||||||
my %OIDs = (
|
|
||||||
pack("CCC", 85, 4, 3) => "commonName",
|
|
||||||
pack("CCC", 85, 4, 6) => "countryName",
|
|
||||||
pack("CCC", 85, 4, 10) => "organizationName",
|
|
||||||
pack("CCC", 85, 4, 11) => "organizationUnitName",
|
|
||||||
pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 1, 1) => "rsaEncryption",
|
|
||||||
pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 1, 5) => "sha1WithRSAEncryption",
|
|
||||||
pack("CCCCCCCCC", 42, 134, 72, 134, 247, 13, 1, 9, 1) => "emailAddress",
|
|
||||||
pack("CCC", 85, 29, 35) => "authorityKeyIdentifier",
|
|
||||||
pack("CCC", 85, 29, 14) => "subjectKeyIdentifier",
|
|
||||||
pack("CCC", 85, 29, 19) => "basicConstraints"
|
|
||||||
);
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# Extract an ASN.1 element from a string and return information about it.
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
sub asn1_extract($$@)
|
|
||||||
{
|
|
||||||
my ($cursor, $expected_tag, $optional) = @_;
|
|
||||||
|
|
||||||
return [ -1 ]
|
|
||||||
if ($cursor->[1] == 0 && $optional);
|
|
||||||
|
|
||||||
die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (elem ", $cursor->[1], ")\n"
|
|
||||||
if ($cursor->[1] < 2);
|
|
||||||
|
|
||||||
my ($tag, $len) = unpack("CC", substr(${$cursor->[2]}, $cursor->[0], 2));
|
|
||||||
|
|
||||||
if ($expected_tag != -1 && $tag != $expected_tag) {
|
|
||||||
return [ -1 ]
|
|
||||||
if ($optional);
|
|
||||||
die $x509, ": ", $cursor->[0], ": ASN.1 unexpected tag (", $tag,
|
|
||||||
" not ", $expected_tag, ")\n";
|
|
||||||
}
|
|
||||||
|
|
||||||
$cursor->[0] += 2;
|
|
||||||
$cursor->[1] -= 2;
|
|
||||||
|
|
||||||
die $x509, ": ", $cursor->[0], ": ASN.1 long tag\n"
|
|
||||||
if (($tag & 0x1f) == 0x1f);
|
|
||||||
die $x509, ": ", $cursor->[0], ": ASN.1 indefinite length\n"
|
|
||||||
if ($len == 0x80);
|
|
||||||
|
|
||||||
if ($len > 0x80) {
|
|
||||||
my $l = $len - 0x80;
|
|
||||||
die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (len len $l)\n"
|
|
||||||
if ($cursor->[1] < $l);
|
|
||||||
|
|
||||||
if ($l == 0x1) {
|
|
||||||
$len = unpack("C", substr(${$cursor->[2]}, $cursor->[0], 1));
|
|
||||||
} elsif ($l == 0x2) {
|
|
||||||
$len = unpack("n", substr(${$cursor->[2]}, $cursor->[0], 2));
|
|
||||||
} elsif ($l == 0x3) {
|
|
||||||
$len = unpack("C", substr(${$cursor->[2]}, $cursor->[0], 1)) << 16;
|
|
||||||
$len = unpack("n", substr(${$cursor->[2]}, $cursor->[0] + 1, 2));
|
|
||||||
} elsif ($l == 0x4) {
|
|
||||||
$len = unpack("N", substr(${$cursor->[2]}, $cursor->[0], 4));
|
|
||||||
} else {
|
|
||||||
die $x509, ": ", $cursor->[0], ": ASN.1 element too long (", $l, ")\n";
|
|
||||||
}
|
|
||||||
|
|
||||||
$cursor->[0] += $l;
|
|
||||||
$cursor->[1] -= $l;
|
|
||||||
}
|
|
||||||
|
|
||||||
die $x509, ": ", $cursor->[0], ": ASN.1 data underrun (", $len, ")\n"
|
|
||||||
if ($cursor->[1] < $len);
|
|
||||||
|
|
||||||
my $ret = [ $tag, [ $cursor->[0], $len, $cursor->[2] ] ];
|
|
||||||
$cursor->[0] += $len;
|
|
||||||
$cursor->[1] -= $len;
|
|
||||||
|
|
||||||
return $ret;
|
|
||||||
}
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# Retrieve the data referred to by a cursor
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
sub asn1_retrieve($)
|
|
||||||
{
|
|
||||||
my ($cursor) = @_;
|
|
||||||
my ($offset, $len, $data) = @$cursor;
|
|
||||||
return substr($$data, $offset, $len);
|
|
||||||
}
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# Roughly parse the X.509 certificate
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
my $cursor = [ 0, length($x509_certificate), \$x509_certificate ];
|
|
||||||
|
|
||||||
my $cert = asn1_extract($cursor, $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $tbs = asn1_extract($cert->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $version = asn1_extract($tbs->[1], $CONT | $CONS | 0, 1);
|
|
||||||
my $serial_number = asn1_extract($tbs->[1], $UNIV | $INTEGER);
|
|
||||||
my $sig_type = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $issuer = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $validity = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $subject = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $key = asn1_extract($tbs->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $issuer_uid = asn1_extract($tbs->[1], $CONT | $CONS | 1, 1);
|
|
||||||
my $subject_uid = asn1_extract($tbs->[1], $CONT | $CONS | 2, 1);
|
|
||||||
my $extension_list = asn1_extract($tbs->[1], $CONT | $CONS | 3, 1);
|
|
||||||
|
|
||||||
my $subject_key_id = ();
|
|
||||||
my $authority_key_id = ();
|
|
||||||
|
|
||||||
#
|
|
||||||
# Parse the extension list
|
|
||||||
#
|
|
||||||
if ($extension_list->[0] != -1) {
|
|
||||||
my $extensions = asn1_extract($extension_list->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
|
|
||||||
while ($extensions->[1]->[1] > 0) {
|
|
||||||
my $ext = asn1_extract($extensions->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $x_oid = asn1_extract($ext->[1], $UNIV | $OBJ_ID);
|
|
||||||
my $x_crit = asn1_extract($ext->[1], $UNIV | $BOOLEAN, 1);
|
|
||||||
my $x_val = asn1_extract($ext->[1], $UNIV | $OCTET_STRING);
|
|
||||||
|
|
||||||
my $raw_oid = asn1_retrieve($x_oid->[1]);
|
|
||||||
next if (!exists($OIDs{$raw_oid}));
|
|
||||||
my $x_type = $OIDs{$raw_oid};
|
|
||||||
|
|
||||||
my $raw_value = asn1_retrieve($x_val->[1]);
|
|
||||||
|
|
||||||
if ($x_type eq "subjectKeyIdentifier") {
|
|
||||||
my $vcursor = [ 0, length($raw_value), \$raw_value ];
|
|
||||||
|
|
||||||
$subject_key_id = asn1_extract($vcursor, $UNIV | $OCTET_STRING);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# Determine what we're going to use as the signer's name. In order of
|
|
||||||
# preference, take one of: commonName, organizationName or emailAddress.
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
my $org = "";
|
|
||||||
my $cn = "";
|
|
||||||
my $email = "";
|
|
||||||
|
|
||||||
while ($subject->[1]->[1] > 0) {
|
|
||||||
my $rdn = asn1_extract($subject->[1], $UNIV | $CONS | $SET);
|
|
||||||
my $attr = asn1_extract($rdn->[1], $UNIV | $CONS | $SEQUENCE);
|
|
||||||
my $n_oid = asn1_extract($attr->[1], $UNIV | $OBJ_ID);
|
|
||||||
my $n_val = asn1_extract($attr->[1], -1);
|
|
||||||
|
|
||||||
my $raw_oid = asn1_retrieve($n_oid->[1]);
|
|
||||||
next if (!exists($OIDs{$raw_oid}));
|
|
||||||
my $n_type = $OIDs{$raw_oid};
|
|
||||||
|
|
||||||
my $raw_value = asn1_retrieve($n_val->[1]);
|
|
||||||
|
|
||||||
if ($n_type eq "organizationName") {
|
|
||||||
$org = $raw_value;
|
|
||||||
} elsif ($n_type eq "commonName") {
|
|
||||||
$cn = $raw_value;
|
|
||||||
} elsif ($n_type eq "emailAddress") {
|
|
||||||
$email = $raw_value;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
my $signers_name = $email;
|
|
||||||
|
|
||||||
if ($org && $cn) {
|
|
||||||
# Don't use the organizationName if the commonName repeats it
|
|
||||||
if (length($org) <= length($cn) &&
|
|
||||||
substr($cn, 0, length($org)) eq $org) {
|
|
||||||
$signers_name = $cn;
|
|
||||||
goto got_id_name;
|
|
||||||
}
|
|
||||||
|
|
||||||
# Or a signifcant chunk of it
|
|
||||||
if (length($org) >= 7 &&
|
|
||||||
length($cn) >= 7 &&
|
|
||||||
substr($cn, 0, 7) eq substr($org, 0, 7)) {
|
|
||||||
$signers_name = $cn;
|
|
||||||
goto got_id_name;
|
|
||||||
}
|
|
||||||
|
|
||||||
$signers_name = $org . ": " . $cn;
|
|
||||||
} elsif ($org) {
|
|
||||||
$signers_name = $org;
|
|
||||||
} elsif ($cn) {
|
|
||||||
$signers_name = $cn;
|
|
||||||
}
|
|
||||||
|
|
||||||
got_id_name:
|
|
||||||
|
|
||||||
die $x509, ": ", "X.509: Couldn't find the Subject Key Identifier extension\n"
|
|
||||||
if (!$subject_key_id);
|
|
||||||
|
|
||||||
my $key_identifier = asn1_retrieve($subject_key_id->[1]);
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# Create and attach the module signature
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
|
|
||||||
#
|
|
||||||
# Signature parameters
|
|
||||||
#
|
|
||||||
my $algo = 1; # Public-key crypto algorithm: RSA
|
|
||||||
my $hash = 0; # Digest algorithm
|
|
||||||
my $id_type = 1; # Identifier type: X.509
|
|
||||||
|
|
||||||
#
|
|
||||||
# Digest the data
|
|
||||||
#
|
|
||||||
my $prologue;
|
|
||||||
if ($dgst eq "sha1") {
|
|
||||||
$prologue = pack("C*",
|
|
||||||
0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
|
|
||||||
0x2B, 0x0E, 0x03, 0x02, 0x1A,
|
|
||||||
0x05, 0x00, 0x04, 0x14);
|
|
||||||
$hash = 2;
|
|
||||||
} elsif ($dgst eq "sha224") {
|
|
||||||
$prologue = pack("C*",
|
|
||||||
0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09,
|
|
||||||
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04,
|
|
||||||
0x05, 0x00, 0x04, 0x1C);
|
|
||||||
$hash = 7;
|
|
||||||
} elsif ($dgst eq "sha256") {
|
|
||||||
$prologue = pack("C*",
|
|
||||||
0x30, 0x31, 0x30, 0x0d, 0x06, 0x09,
|
|
||||||
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01,
|
|
||||||
0x05, 0x00, 0x04, 0x20);
|
|
||||||
$hash = 4;
|
|
||||||
} elsif ($dgst eq "sha384") {
|
|
||||||
$prologue = pack("C*",
|
|
||||||
0x30, 0x41, 0x30, 0x0d, 0x06, 0x09,
|
|
||||||
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02,
|
|
||||||
0x05, 0x00, 0x04, 0x30);
|
|
||||||
$hash = 5;
|
|
||||||
} elsif ($dgst eq "sha512") {
|
|
||||||
$prologue = pack("C*",
|
|
||||||
0x30, 0x51, 0x30, 0x0d, 0x06, 0x09,
|
|
||||||
0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03,
|
|
||||||
0x05, 0x00, 0x04, 0x40);
|
|
||||||
$hash = 6;
|
|
||||||
} else {
|
|
||||||
die "Unknown hash algorithm: $dgst\n";
|
|
||||||
}
|
|
||||||
|
|
||||||
my $signature;
|
|
||||||
if ($signature_file) {
|
|
||||||
$signature = read_file($signature_file);
|
|
||||||
} else {
|
|
||||||
#
|
|
||||||
# Generate the digest and read from openssl's stdout
|
|
||||||
#
|
|
||||||
my $digest;
|
|
||||||
$digest = readpipe("openssl dgst -$dgst -binary $module") || die "openssl dgst";
|
|
||||||
|
|
||||||
#
|
|
||||||
# Generate the binary signature, which will be just the integer that
|
|
||||||
# comprises the signature with no metadata attached.
|
|
||||||
#
|
|
||||||
my $pid;
|
|
||||||
$pid = open2(*read_from, *write_to,
|
|
||||||
"openssl rsautl -sign -inkey $private_key -keyform PEM") ||
|
|
||||||
die "openssl rsautl";
|
|
||||||
binmode write_to;
|
|
||||||
print write_to $prologue . $digest || die "pipe to openssl rsautl";
|
|
||||||
close(write_to) || die "pipe to openssl rsautl";
|
|
||||||
|
|
||||||
binmode read_from;
|
|
||||||
read(read_from, $signature, 4096) || die "pipe from openssl rsautl";
|
|
||||||
close(read_from) || die "pipe from openssl rsautl";
|
|
||||||
waitpid($pid, 0) || die;
|
|
||||||
die "openssl rsautl died: $?" if ($? >> 8);
|
|
||||||
}
|
|
||||||
$signature = pack("n", length($signature)) . $signature,
|
|
||||||
|
|
||||||
#
|
|
||||||
# Build the signed binary
|
|
||||||
#
|
|
||||||
my $unsigned_module = read_file($module);
|
|
||||||
|
|
||||||
my $magic_number = "~Module signature appended~\n";
|
|
||||||
|
|
||||||
my $info = pack("CCCCCxxxN",
|
|
||||||
$algo, $hash, $id_type,
|
|
||||||
length($signers_name),
|
|
||||||
length($key_identifier),
|
|
||||||
length($signature));
|
|
||||||
|
|
||||||
if ($verbose) {
|
|
||||||
print "Size of unsigned module: ", length($unsigned_module), "\n";
|
|
||||||
print "Size of signer's name : ", length($signers_name), "\n";
|
|
||||||
print "Size of key identifier : ", length($key_identifier), "\n";
|
|
||||||
print "Size of signature : ", length($signature), "\n";
|
|
||||||
print "Size of information : ", length($info), "\n";
|
|
||||||
print "Size of magic number : ", length($magic_number), "\n";
|
|
||||||
print "Signer's name : '", $signers_name, "'\n";
|
|
||||||
print "Digest : $dgst\n";
|
|
||||||
}
|
|
||||||
|
|
||||||
open(FD, ">$dest") || die $dest;
|
|
||||||
binmode FD;
|
|
||||||
print FD
|
|
||||||
$unsigned_module,
|
|
||||||
$signers_name,
|
|
||||||
$key_identifier,
|
|
||||||
$signature,
|
|
||||||
$info,
|
|
||||||
$magic_number
|
|
||||||
;
|
|
||||||
close FD || die $dest;
|
|
||||||
|
|
||||||
if (!$keep_orig) {
|
|
||||||
rename($dest, $module) || die $module;
|
|
||||||
}
|
|
||||||
Loading…
Reference in a new issue