Allow TSS2 PRIVATE KEY and TSS2 KEY BLOB ASN.1 to diverge

... and indeed do so. Make the pubkey and parent non-optional, for
a start, but leave the type field alone for now. The explicit tag
of the policy field can change because it's harmles to do so.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
[jejb: plumb policy in correctly]
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

3 files changed, 62 insertions, 22 deletions

diff --git a/create_tpm2_key.c b/create_tpm2_key.c
index 2c71ed3..06bcb84 100644
--- a/create_tpm2_key.c
+++ b/create_tpm2_key.c
@@ -236,7 +236,7 @@ openssl_write_tpmfile(const char *file, BYTE *pubkey, int pubkey_len,
 		      BYTE *privkey, int privkey_len, int empty_auth,
 		      TPM_HANDLE parent, STACK_OF(TSSOPTPOLICY) *sk)
 {
-	TSSLOADABLE tssl;
+	TSSPRIVKEY tssl;
 	BIO *outb;
 
 	/* clear structure so as not to have to set optional parameters */
diff --git a/e_tpm2.c b/e_tpm2.c
index f440d16..fd0ed1c 100644
--- a/e_tpm2.c
+++ b/e_tpm2.c
@@ -271,13 +271,13 @@ static int tpm2_engine_load_nvkey(ENGINE *e, EVP_PKEY **ppkey,
 }
 
 static int tpm2_engine_load_key_policy(struct app_data *app_data,
-				       TSSLOADABLE *tssl)
+				       STACK_OF(TSSOPTPOLICY) *st_policy)
 {
 	struct policy_command *command;
 	TSSOPTPOLICY *policy;
 	int i, commands_len;
 
-	app_data->num_commands = sk_TSSOPTPOLICY_num(tssl->policy);
+	app_data->num_commands = sk_TSSOPTPOLICY_num(st_policy);
 	if (app_data->num_commands <= 0)
 		return 1;
 
@@ -287,7 +287,7 @@ static int tpm2_engine_load_key_policy(struct app_data *app_data,
 		return 0;
 
 	for (i = 0; i < app_data->num_commands; i++) {
-		policy = sk_TSSOPTPOLICY_value(tssl->policy, i);
+		policy = sk_TSSOPTPOLICY_value(st_policy, i);
 		if (!policy)
 			return 0;
 
@@ -317,13 +317,19 @@ static int tpm2_engine_load_key_core(ENGINE *e, EVP_PKEY **ppkey,
 	EVP_PKEY *pkey;
 	TPM2B_PUBLIC p;
 	BIO *bf;
-	TSSLOADABLE *tssl;
+	TSSLOADABLE *tssl = NULL;
+	TSSPRIVKEY *tpk = NULL;
 	BYTE *buffer;
 	INT32 size;
 	struct app_data *app_data;
 	char oid[128];
 	int empty_auth, version = 0;
 	const int nvkey_len = strlen(nvprefix);
+	ASN1_OBJECT *type;
+	ASN1_INTEGER *parent;
+	ASN1_OCTET_STRING *pubkey;
+	STACK_OF(TSSOPTPOLICY) *policy;
+	ASN1_OCTET_STRING *privkey;
 
 	if (!key_id && !bio) {
 		fprintf(stderr, "key_id or bio is NULL\n");
@@ -351,18 +357,32 @@ static int tpm2_engine_load_key_core(ENGINE *e, EVP_PKEY **ppkey,
 		return 0;
 	}
 
-	tssl = PEM_read_bio_TSSPRIVKEY(bf, NULL, NULL, NULL);
-	if (tssl) {
+	tpk = PEM_read_bio_TSSPRIVKEY(bf, NULL, NULL, NULL);
+	if (tpk) {
 		version = 1;
+		type = tpk->type;
+		empty_auth = tpk->emptyAuth;
+		parent = tpk->parent;
+		pubkey = tpk->pubkey;
+		privkey = tpk->privkey;
+		policy = tpk->policy;
 	} else {
 		BIO_seek(bf, 0);
 		tssl = PEM_read_bio_TSSLOADABLE(bf, NULL, NULL, NULL);
+		if (tssl) {
+			type = tssl->type;
+			empty_auth = tssl->emptyAuth;
+			parent = tssl->parent;
+			pubkey = tssl->pubkey;
+			privkey = tssl->privkey;
+			policy = tssl->policy;
+		}
 	}
 
 	if (!bio)
 		BIO_free(bf);
 
-	if (!tssl) {
+	if (!tssl && !tpk) {
 		if (ppkey)
 			fprintf(stderr, "Failed to parse file %s\n", key_id);
 		return 0;
@@ -370,10 +390,11 @@ static int tpm2_engine_load_key_core(ENGINE *e, EVP_PKEY **ppkey,
 
 	if (!ppkey) {
 		TSSLOADABLE_free(tssl);
+		TSSPRIVKEY_free(tpk);
 		return 1;
 	}
 
-	if (OBJ_obj2txt(oid, sizeof(oid), tssl->type, 1) == 0) {
+	if (OBJ_obj2txt(oid, sizeof(oid), type, 1) == 0) {
 		fprintf(stderr, "Failed to parse object type\n");
 		goto err;
 	}
@@ -402,25 +423,23 @@ static int tpm2_engine_load_key_core(ENGINE *e, EVP_PKEY **ppkey,
 	app_data->version = version;
 	app_data->dir = tpm2_set_unique_tssdir();
 
-	if (tssl->parent)
-		app_data->parent = ASN1_INTEGER_get(tssl->parent);
+	if (parent)
+		app_data->parent = ASN1_INTEGER_get(parent);
 	else
 		/* older keys have absent parent */
 		app_data->parent = TPM_RH_OWNER;
 
-	empty_auth = tssl->emptyAuth;
-
-	app_data->priv = OPENSSL_malloc(tssl->privkey->length);
+	app_data->priv = OPENSSL_malloc(privkey->length);
 	if (!app_data->priv)
 		goto err_free;
-	app_data->priv_len = tssl->privkey->length;
-	memcpy(app_data->priv, tssl->privkey->data, app_data->priv_len);
+	app_data->priv_len = privkey->length;
+	memcpy(app_data->priv, privkey->data, app_data->priv_len);
 
-	app_data->pub = OPENSSL_malloc(tssl->pubkey->length);
+	app_data->pub = OPENSSL_malloc(pubkey->length);
 	if (!app_data->pub)
 		goto err_free;
-	app_data->pub_len = tssl->pubkey->length;
-	memcpy(app_data->pub, tssl->pubkey->data, app_data->pub_len);
+	app_data->pub_len = pubkey->length;
+	memcpy(app_data->pub, pubkey->data, app_data->pub_len);
 	buffer = app_data->pub;
 	size = app_data->pub_len;
 	TPM2B_PUBLIC_Unmarshal(&p, &buffer, &size, FALSE);
@@ -440,10 +459,11 @@ static int tpm2_engine_load_key_core(ENGINE *e, EVP_PKEY **ppkey,
 	if (!(p.publicArea.objectAttributes.val & TPMA_OBJECT_USERWITHAUTH))
 		app_data->req_policy_session = 1;
 
-	if (!tpm2_engine_load_key_policy(app_data, tssl))
+	if (!tpm2_engine_load_key_policy(app_data, policy))
 		goto err_free_key;
 
 	TSSLOADABLE_free(tssl);
+	TSSPRIVKEY_free(tpk);
 
 	tpm2_bind_key_to_engine(pkey, app_data);
 
diff --git a/tpm2-asn.h b/tpm2-asn.h
index 5c78cdd..341edb5 100644
--- a/tpm2-asn.h
+++ b/tpm2-asn.h
@@ -68,6 +68,15 @@ typedef struct {
 	ASN1_OCTET_STRING *privkey;
 } TSSLOADABLE;
 
+typedef struct {
+	ASN1_OBJECT *type;
+	ASN1_BOOLEAN emptyAuth;
+	STACK_OF(TSSOPTPOLICY) *policy;
+	ASN1_INTEGER *parent;
+	ASN1_OCTET_STRING *pubkey;
+	ASN1_OCTET_STRING *privkey;
+} TSSPRIVKEY;
+
 /* the two type oids are in the TCG namespace 2.23.133; we choose an
  *  unoccupied child (10) for keytype file and two values:
  *    1 : Key that is directly loadable
@@ -88,13 +97,24 @@ ASN1_SEQUENCE(TSSLOADABLE) = {
 
 IMPLEMENT_ASN1_FUNCTIONS(TSSLOADABLE);
 
+ASN1_SEQUENCE(TSSPRIVKEY) = {
+	ASN1_SIMPLE(TSSPRIVKEY, type, ASN1_OBJECT),
+	ASN1_EXP_OPT(TSSPRIVKEY, emptyAuth, ASN1_BOOLEAN, 0),
+	ASN1_EXP_SEQUENCE_OF_OPT(TSSPRIVKEY, policy, TSSOPTPOLICY, 1),
+	ASN1_SIMPLE(TSSPRIVKEY, parent, ASN1_INTEGER),
+	ASN1_SIMPLE(TSSPRIVKEY, pubkey, ASN1_OCTET_STRING),
+	ASN1_SIMPLE(TSSPRIVKEY, privkey, ASN1_OCTET_STRING)
+} ASN1_SEQUENCE_END(TSSPRIVKEY)
+
+IMPLEMENT_ASN1_FUNCTIONS(TSSPRIVKEY);
+
 /* This is the PEM guard tag */
 #define TSSLOADABLE_PEM_STRING "TSS2 KEY BLOB"
 #define TSSPRIVKEY_PEM_STRING "TSS2 PRIVATE KEY"
 
 static IMPLEMENT_PEM_write_bio(TSSLOADABLE, TSSLOADABLE, TSSLOADABLE_PEM_STRING, TSSLOADABLE)
 static IMPLEMENT_PEM_read_bio(TSSLOADABLE, TSSLOADABLE, TSSLOADABLE_PEM_STRING, TSSLOADABLE)
-static IMPLEMENT_PEM_write_bio(TSSPRIVKEY, TSSLOADABLE, TSSPRIVKEY_PEM_STRING, TSSLOADABLE)
-static IMPLEMENT_PEM_read_bio(TSSPRIVKEY, TSSLOADABLE, TSSPRIVKEY_PEM_STRING, TSSLOADABLE)
+static IMPLEMENT_PEM_write_bio(TSSPRIVKEY, TSSPRIVKEY, TSSPRIVKEY_PEM_STRING, TSSPRIVKEY)
+static IMPLEMENT_PEM_read_bio(TSSPRIVKEY, TSSPRIVKEY, TSSPRIVKEY_PEM_STRING, TSSPRIVKEY)
 
 #endif