Adding upstream version 1.14.0.upstream/1.14.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1230 insertions, 0 deletions

diff --git a/src/cred.c b/src/cred.c
new file mode 100644
index 0000000..4a7a725
--- /dev/null
+++ b/src/cred.c
@@ -0,0 +1,1230 @@
+/*
+ * Copyright (c) 2018-2022 Yubico AB. All rights reserved.
+ * Use of this source code is governed by a BSD-style
+ * license that can be found in the LICENSE file.
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <openssl/sha.h>
+#include <openssl/x509.h>
+
+#include "fido.h"
+#include "fido/es256.h"
+
+#ifndef FIDO_MAXMSG_CRED
+#define FIDO_MAXMSG_CRED	4096
+#endif
+
+static int
+parse_makecred_reply(const cbor_item_t *key, const cbor_item_t *val, void *arg)
+{
+	fido_cred_t *cred = arg;
+
+	if (cbor_isa_uint(key) == false ||
+	    cbor_int_get_width(key) != CBOR_INT_8) {
+		fido_log_debug("%s: cbor type", __func__);
+		return (0); /* ignore */
+	}
+
+	switch (cbor_get_uint8(key)) {
+	case 1: /* fmt */
+		return (cbor_decode_fmt(val, &cred->fmt));
+	case 2: /* authdata */
+		if (fido_blob_decode(val, &cred->authdata_raw) < 0) {
+			fido_log_debug("%s: fido_blob_decode", __func__);
+			return (-1);
+		}
+		return (cbor_decode_cred_authdata(val, cred->type,
+		    &cred->authdata_cbor, &cred->authdata, &cred->attcred,
+		    &cred->authdata_ext));
+	case 3: /* attestation statement */
+		return (cbor_decode_attstmt(val, &cred->attstmt));
+	case 5: /* large blob key */
+		return (fido_blob_decode(val, &cred->largeblob_key));
+	default: /* ignore */
+		fido_log_debug("%s: cbor type", __func__);
+		return (0);
+	}
+}
+
+static int
+fido_dev_make_cred_tx(fido_dev_t *dev, fido_cred_t *cred, const char *pin,
+    int *ms)
+{
+	fido_blob_t	 f;
+	fido_blob_t	*ecdh = NULL;
+	fido_opt_t	 uv = cred->uv;
+	es256_pk_t	*pk = NULL;
+	cbor_item_t	*argv[9];
+	const uint8_t	 cmd = CTAP_CBOR_MAKECRED;
+	int		 r;
+
+	memset(&f, 0, sizeof(f));
+	memset(argv, 0, sizeof(argv));
+
+	if (cred->cdh.ptr == NULL || cred->type == 0) {
+		fido_log_debug("%s: cdh=%p, type=%d", __func__,
+		    (void *)cred->cdh.ptr, cred->type);
+		r = FIDO_ERR_INVALID_ARGUMENT;
+		goto fail;
+	}
+
+	if ((argv[0] = fido_blob_encode(&cred->cdh)) == NULL ||
+	    (argv[1] = cbor_encode_rp_entity(&cred->rp)) == NULL ||
+	    (argv[2] = cbor_encode_user_entity(&cred->user)) == NULL ||
+	    (argv[3] = cbor_encode_pubkey_param(cred->type)) == NULL) {
+		fido_log_debug("%s: cbor encode", __func__);
+		r = FIDO_ERR_INTERNAL;
+		goto fail;
+	}
+
+	/* excluded credentials */
+	if (cred->excl.len)
+		if ((argv[4] = cbor_encode_pubkey_list(&cred->excl)) == NULL) {
+			fido_log_debug("%s: cbor_encode_pubkey_list", __func__);
+			r = FIDO_ERR_INTERNAL;
+			goto fail;
+		}
+
+	/* extensions */
+	if (cred->ext.mask)
+		if ((argv[5] = cbor_encode_cred_ext(&cred->ext,
+		    &cred->blob)) == NULL) {
+			fido_log_debug("%s: cbor_encode_cred_ext", __func__);
+			r = FIDO_ERR_INTERNAL;
+			goto fail;
+		}
+
+	/* user verification */
+	if (pin != NULL || (uv == FIDO_OPT_TRUE &&
+	    fido_dev_supports_permissions(dev))) {
+		if ((r = fido_do_ecdh(dev, &pk, &ecdh, ms)) != FIDO_OK) {
+			fido_log_debug("%s: fido_do_ecdh", __func__);
+			goto fail;
+		}
+		if ((r = cbor_add_uv_params(dev, cmd, &cred->cdh, pk, ecdh,
+		    pin, cred->rp.id, &argv[7], &argv[8], ms)) != FIDO_OK) {
+			fido_log_debug("%s: cbor_add_uv_params", __func__);
+			goto fail;
+		}
+		uv = FIDO_OPT_OMIT;
+	}
+
+	/* options */
+	if (cred->rk != FIDO_OPT_OMIT || uv != FIDO_OPT_OMIT)
+		if ((argv[6] = cbor_encode_cred_opt(cred->rk, uv)) == NULL) {
+			fido_log_debug("%s: cbor_encode_cred_opt", __func__);
+			r = FIDO_ERR_INTERNAL;
+			goto fail;
+		}
+
+	/* framing and transmission */
+	if (cbor_build_frame(cmd, argv, nitems(argv), &f) < 0 ||
+	    fido_tx(dev, CTAP_CMD_CBOR, f.ptr, f.len, ms) < 0) {
+		fido_log_debug("%s: fido_tx", __func__);
+		r = FIDO_ERR_TX;
+		goto fail;
+	}
+
+	r = FIDO_OK;
+fail:
+	es256_pk_free(&pk);
+	fido_blob_free(&ecdh);
+	cbor_vector_free(argv, nitems(argv));
+	free(f.ptr);
+
+	return (r);
+}
+
+static int
+fido_dev_make_cred_rx(fido_dev_t *dev, fido_cred_t *cred, int *ms)
+{
+	unsigned char	*reply;
+	int		 reply_len;
+	int		 r;
+
+	fido_cred_reset_rx(cred);
+
+	if ((reply = malloc(FIDO_MAXMSG_CRED)) == NULL) {
+		r = FIDO_ERR_INTERNAL;
+		goto fail;
+	}
+
+	if ((reply_len = fido_rx(dev, CTAP_CMD_CBOR, reply, FIDO_MAXMSG_CRED,
+	    ms)) < 0) {
+		fido_log_debug("%s: fido_rx", __func__);
+		r = FIDO_ERR_RX;
+		goto fail;
+	}
+
+	if ((r = cbor_parse_reply(reply, (size_t)reply_len, cred,
+	    parse_makecred_reply)) != FIDO_OK) {
+		fido_log_debug("%s: parse_makecred_reply", __func__);
+		goto fail;
+	}
+
+	if (cred->fmt == NULL || fido_blob_is_empty(&cred->authdata_cbor) ||
+	    fido_blob_is_empty(&cred->attcred.id)) {
+		r = FIDO_ERR_INVALID_CBOR;
+		goto fail;
+	}
+
+	r = FIDO_OK;
+fail:
+	free(reply);
+
+	if (r != FIDO_OK)
+		fido_cred_reset_rx(cred);
+
+	return (r);
+}
+
+static int
+fido_dev_make_cred_wait(fido_dev_t *dev, fido_cred_t *cred, const char *pin,
+    int *ms)
+{
+	int  r;
+
+	if ((r = fido_dev_make_cred_tx(dev, cred, pin, ms)) != FIDO_OK ||
+	    (r = fido_dev_make_cred_rx(dev, cred, ms)) != FIDO_OK)
+		return (r);
+
+	return (FIDO_OK);
+}
+
+int
+fido_dev_make_cred(fido_dev_t *dev, fido_cred_t *cred, const char *pin)
+{
+	int ms = dev->timeout_ms;
+
+#ifdef USE_WINHELLO
+	if (dev->flags & FIDO_DEV_WINHELLO)
+		return (fido_winhello_make_cred(dev, cred, pin, ms));
+#endif
+	if (fido_dev_is_fido2(dev) == false) {
+		if (pin != NULL || cred->rk == FIDO_OPT_TRUE ||
+		    cred->ext.mask != 0)
+			return (FIDO_ERR_UNSUPPORTED_OPTION);
+		return (u2f_register(dev, cred, &ms));
+	}
+
+	return (fido_dev_make_cred_wait(dev, cred, pin, &ms));
+}
+
+static int
+check_extensions(const fido_cred_ext_t *authdata_ext,
+    const fido_cred_ext_t *ext)
+{
+	fido_cred_ext_t	 tmp;
+
+	/* XXX: largeBlobKey is not part of the extensions map */
+	memcpy(&tmp, ext, sizeof(tmp));
+	tmp.mask &= ~FIDO_EXT_LARGEBLOB_KEY;
+
+	return (timingsafe_bcmp(authdata_ext, &tmp, sizeof(*authdata_ext)));
+}
+
+int
+fido_check_rp_id(const char *id, const unsigned char *obtained_hash)
+{
+	unsigned char expected_hash[SHA256_DIGEST_LENGTH];
+
+	explicit_bzero(expected_hash, sizeof(expected_hash));
+
+	if (SHA256((const unsigned char *)id, strlen(id),
+	    expected_hash) != expected_hash) {
+		fido_log_debug("%s: sha256", __func__);
+		return (-1);
+	}
+
+	return (timingsafe_bcmp(expected_hash, obtained_hash,
+	    SHA256_DIGEST_LENGTH));
+}
+
+static int
+get_signed_hash_u2f(fido_blob_t *dgst, const unsigned char *rp_id,
+    size_t rp_id_len, const fido_blob_t *clientdata, const fido_blob_t *id,
+    const es256_pk_t *pk)
+{
+	const uint8_t	 zero = 0;
+	const uint8_t	 four = 4; /* uncompressed point */
+	const EVP_MD	*md = NULL;
+	EVP_MD_CTX	*ctx = NULL;
+	int		 ok = -1;
+
+	if (dgst->len < SHA256_DIGEST_LENGTH ||
+	    (md = EVP_sha256()) == NULL ||
+	    (ctx = EVP_MD_CTX_new()) == NULL ||
+	    EVP_DigestInit_ex(ctx, md, NULL) != 1 ||
+	    EVP_DigestUpdate(ctx, &zero, sizeof(zero)) != 1 ||
+	    EVP_DigestUpdate(ctx, rp_id, rp_id_len) != 1 ||
+	    EVP_DigestUpdate(ctx, clientdata->ptr, clientdata->len) != 1 ||
+	    EVP_DigestUpdate(ctx, id->ptr, id->len) != 1 ||
+	    EVP_DigestUpdate(ctx, &four, sizeof(four)) != 1 ||
+	    EVP_DigestUpdate(ctx, pk->x, sizeof(pk->x)) != 1 ||
+	    EVP_DigestUpdate(ctx, pk->y, sizeof(pk->y)) != 1 ||
+	    EVP_DigestFinal_ex(ctx, dgst->ptr, NULL) != 1) {
+		fido_log_debug("%s: sha256", __func__);
+		goto fail;
+	}
+	dgst->len = SHA256_DIGEST_LENGTH;
+
+	ok = 0;
+fail:
+	EVP_MD_CTX_free(ctx);
+
+	return (ok);
+}
+
+static int
+verify_attstmt(const fido_blob_t *dgst, const fido_attstmt_t *attstmt)
+{
+	BIO		*rawcert = NULL;
+	X509		*cert = NULL;
+	EVP_PKEY	*pkey = NULL;
+	int		 ok = -1;
+
+	/* openssl needs ints */
+	if (attstmt->x5c.len > INT_MAX) {
+		fido_log_debug("%s: x5c.len=%zu", __func__, attstmt->x5c.len);
+		return (-1);
+	}
+
+	/* fetch key from x509 */
+	if ((rawcert = BIO_new_mem_buf(attstmt->x5c.ptr,
+	    (int)attstmt->x5c.len)) == NULL ||
+	    (cert = d2i_X509_bio(rawcert, NULL)) == NULL ||
+	    (pkey = X509_get_pubkey(cert)) == NULL) {
+		fido_log_debug("%s: x509 key", __func__);
+		goto fail;
+	}
+
+	switch (attstmt->alg) {
+	case COSE_UNSPEC:
+	case COSE_ES256:
+		ok = es256_verify_sig(dgst, pkey, &attstmt->sig);
+		break;
+	case COSE_ES384:
+		ok = es384_verify_sig(dgst, pkey, &attstmt->sig);
+		break;
+	case COSE_RS256:
+		ok = rs256_verify_sig(dgst, pkey, &attstmt->sig);
+		break;
+	case COSE_RS1:
+		ok = rs1_verify_sig(dgst, pkey, &attstmt->sig);
+		break;
+	case COSE_EDDSA:
+		ok = eddsa_verify_sig(dgst, pkey, &attstmt->sig);
+		break;
+	default:
+		fido_log_debug("%s: unknown alg %d", __func__, attstmt->alg);
+		break;
+	}
+
+fail:
+	BIO_free(rawcert);
+	X509_free(cert);
+	EVP_PKEY_free(pkey);
+
+	return (ok);
+}
+
+int
+fido_cred_verify(const fido_cred_t *cred)
+{
+	unsigned char	buf[1024]; /* XXX */
+	fido_blob_t	dgst;
+	int		cose_alg;
+	int		r;
+
+	dgst.ptr = buf;
+	dgst.len = sizeof(buf);
+
+	/* do we have everything we need? */
+	if (cred->cdh.ptr == NULL || cred->authdata_cbor.ptr == NULL ||
+	    cred->attstmt.x5c.ptr == NULL || cred->attstmt.sig.ptr == NULL ||
+	    cred->fmt == NULL || cred->attcred.id.ptr == NULL ||
+	    cred->rp.id == NULL) {
+		fido_log_debug("%s: cdh=%p, authdata=%p, x5c=%p, sig=%p, "
+		    "fmt=%p id=%p, rp.id=%s", __func__, (void *)cred->cdh.ptr,
+		    (void *)cred->authdata_cbor.ptr,
+		    (void *)cred->attstmt.x5c.ptr,
+		    (void *)cred->attstmt.sig.ptr, (void *)cred->fmt,
+		    (void *)cred->attcred.id.ptr, cred->rp.id);
+		r = FIDO_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+
+	if (fido_check_rp_id(cred->rp.id, cred->authdata.rp_id_hash) != 0) {
+		fido_log_debug("%s: fido_check_rp_id", __func__);
+		r = FIDO_ERR_INVALID_PARAM;
+		goto out;
+	}
+
+	if (fido_check_flags(cred->authdata.flags, FIDO_OPT_TRUE,
+	    cred->uv) < 0) {
+		fido_log_debug("%s: fido_check_flags", __func__);
+		r = FIDO_ERR_INVALID_PARAM;
+		goto out;
+	}
+
+	if (check_extensions(&cred->authdata_ext, &cred->ext) != 0) {
+		fido_log_debug("%s: check_extensions", __func__);
+		r = FIDO_ERR_INVALID_PARAM;
+		goto out;
+	}
+
+	if ((cose_alg = cred->attstmt.alg) == COSE_UNSPEC)
+		cose_alg = COSE_ES256; /* backwards compat */
+
+	if (!strcmp(cred->fmt, "packed")) {
+		if (fido_get_signed_hash(cose_alg, &dgst, &cred->cdh,
+		    &cred->authdata_cbor) < 0) {
+			fido_log_debug("%s: fido_get_signed_hash", __func__);
+			r = FIDO_ERR_INTERNAL;
+			goto out;
+		}
+	} else if (!strcmp(cred->fmt, "fido-u2f")) {
+		if (get_signed_hash_u2f(&dgst, cred->authdata.rp_id_hash,
+		    sizeof(cred->authdata.rp_id_hash), &cred->cdh,
+		    &cred->attcred.id, &cred->attcred.pubkey.es256) < 0) {
+			fido_log_debug("%s: get_signed_hash_u2f", __func__);
+			r = FIDO_ERR_INTERNAL;
+			goto out;
+		}
+	} else if (!strcmp(cred->fmt, "tpm")) {
+		if (fido_get_signed_hash_tpm(&dgst, &cred->cdh,
+		    &cred->authdata_raw, &cred->attstmt, &cred->attcred) < 0) {
+			fido_log_debug("%s: fido_get_signed_hash_tpm", __func__);
+			r = FIDO_ERR_INTERNAL;
+			goto out;
+		}
+	} else {
+		fido_log_debug("%s: unknown fmt %s", __func__, cred->fmt);
+		r = FIDO_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+
+	if (verify_attstmt(&dgst, &cred->attstmt) < 0) {
+		fido_log_debug("%s: verify_attstmt", __func__);
+		r = FIDO_ERR_INVALID_SIG;
+		goto out;
+	}
+
+	r = FIDO_OK;
+out:
+	explicit_bzero(buf, sizeof(buf));
+
+	return (r);
+}
+
+int
+fido_cred_verify_self(const fido_cred_t *cred)
+{
+	unsigned char	buf[1024]; /* XXX */
+	fido_blob_t	dgst;
+	int		ok = -1;
+	int		r;
+
+	dgst.ptr = buf;
+	dgst.len = sizeof(buf);
+
+	/* do we have everything we need? */
+	if (cred->cdh.ptr == NULL || cred->authdata_cbor.ptr == NULL ||
+	    cred->attstmt.x5c.ptr != NULL || cred->attstmt.sig.ptr == NULL ||
+	    cred->fmt == NULL || cred->attcred.id.ptr == NULL ||
+	    cred->rp.id == NULL) {
+		fido_log_debug("%s: cdh=%p, authdata=%p, x5c=%p, sig=%p, "
+		    "fmt=%p id=%p, rp.id=%s", __func__, (void *)cred->cdh.ptr,
+		    (void *)cred->authdata_cbor.ptr,
+		    (void *)cred->attstmt.x5c.ptr,
+		    (void *)cred->attstmt.sig.ptr, (void *)cred->fmt,
+		    (void *)cred->attcred.id.ptr, cred->rp.id);
+		r = FIDO_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+
+	if (fido_check_rp_id(cred->rp.id, cred->authdata.rp_id_hash) != 0) {
+		fido_log_debug("%s: fido_check_rp_id", __func__);
+		r = FIDO_ERR_INVALID_PARAM;
+		goto out;
+	}
+
+	if (fido_check_flags(cred->authdata.flags, FIDO_OPT_TRUE,
+	    cred->uv) < 0) {
+		fido_log_debug("%s: fido_check_flags", __func__);
+		r = FIDO_ERR_INVALID_PARAM;
+		goto out;
+	}
+
+	if (check_extensions(&cred->authdata_ext, &cred->ext) != 0) {
+		fido_log_debug("%s: check_extensions", __func__);
+		r = FIDO_ERR_INVALID_PARAM;
+		goto out;
+	}
+
+	if (!strcmp(cred->fmt, "packed")) {
+		if (fido_get_signed_hash(cred->attcred.type, &dgst, &cred->cdh,
+		    &cred->authdata_cbor) < 0) {
+			fido_log_debug("%s: fido_get_signed_hash", __func__);
+			r = FIDO_ERR_INTERNAL;
+			goto out;
+		}
+	} else if (!strcmp(cred->fmt, "fido-u2f")) {
+		if (get_signed_hash_u2f(&dgst, cred->authdata.rp_id_hash,
+		    sizeof(cred->authdata.rp_id_hash), &cred->cdh,
+		    &cred->attcred.id, &cred->attcred.pubkey.es256) < 0) {
+			fido_log_debug("%s: get_signed_hash_u2f", __func__);
+			r = FIDO_ERR_INTERNAL;
+			goto out;
+		}
+	} else {
+		fido_log_debug("%s: unknown fmt %s", __func__, cred->fmt);
+		r = FIDO_ERR_INVALID_ARGUMENT;
+		goto out;
+	}
+
+	switch (cred->attcred.type) {
+	case COSE_ES256:
+		ok = es256_pk_verify_sig(&dgst, &cred->attcred.pubkey.es256,
+		    &cred->attstmt.sig);
+		break;
+	case COSE_ES384:
+		ok = es384_pk_verify_sig(&dgst, &cred->attcred.pubkey.es384,
+		    &cred->attstmt.sig);
+		break;
+	case COSE_RS256:
+		ok = rs256_pk_verify_sig(&dgst, &cred->attcred.pubkey.rs256,
+		    &cred->attstmt.sig);
+		break;
+	case COSE_EDDSA:
+		ok = eddsa_pk_verify_sig(&dgst, &cred->attcred.pubkey.eddsa,
+		    &cred->attstmt.sig);
+		break;
+	default:
+		fido_log_debug("%s: unsupported cose_alg %d", __func__,
+		    cred->attcred.type);
+		r = FIDO_ERR_UNSUPPORTED_OPTION;
+		goto out;
+	}
+
+	if (ok < 0)
+		r = FIDO_ERR_INVALID_SIG;
+	else
+		r = FIDO_OK;
+
+out:
+	explicit_bzero(buf, sizeof(buf));
+
+	return (r);
+}
+
+fido_cred_t *
+fido_cred_new(void)
+{
+	return (calloc(1, sizeof(fido_cred_t)));
+}
+
+static void
+fido_cred_clean_authdata(fido_cred_t *cred)
+{
+	fido_blob_reset(&cred->authdata_cbor);
+	fido_blob_reset(&cred->authdata_raw);
+	fido_blob_reset(&cred->attcred.id);
+
+	memset(&cred->authdata_ext, 0, sizeof(cred->authdata_ext));
+	memset(&cred->authdata, 0, sizeof(cred->authdata));
+	memset(&cred->attcred, 0, sizeof(cred->attcred));
+}
+
+static void
+fido_cred_clean_attstmt(fido_attstmt_t *attstmt)
+{
+	fido_blob_reset(&attstmt->certinfo);
+	fido_blob_reset(&attstmt->pubarea);
+	fido_blob_reset(&attstmt->cbor);
+	fido_blob_reset(&attstmt->x5c);
+	fido_blob_reset(&attstmt->sig);
+
+	memset(attstmt, 0, sizeof(*attstmt));
+}
+
+void
+fido_cred_reset_tx(fido_cred_t *cred)
+{
+	fido_blob_reset(&cred->cd);
+	fido_blob_reset(&cred->cdh);
+	fido_blob_reset(&cred->user.id);
+	fido_blob_reset(&cred->blob);
+
+	free(cred->rp.id);
+	free(cred->rp.name);
+	free(cred->user.icon);
+	free(cred->user.name);
+	free(cred->user.display_name);
+	fido_cred_empty_exclude_list(cred);
+
+	memset(&cred->rp, 0, sizeof(cred->rp));
+	memset(&cred->user, 0, sizeof(cred->user));
+	memset(&cred->ext, 0, sizeof(cred->ext));
+
+	cred->type = 0;
+	cred->rk = FIDO_OPT_OMIT;
+	cred->uv = FIDO_OPT_OMIT;
+}
+
+void
+fido_cred_reset_rx(fido_cred_t *cred)
+{
+	free(cred->fmt);
+	cred->fmt = NULL;
+	fido_cred_clean_authdata(cred);
+	fido_cred_clean_attstmt(&cred->attstmt);
+	fido_blob_reset(&cred->largeblob_key);
+}
+
+void
+fido_cred_free(fido_cred_t **cred_p)
+{
+	fido_cred_t *cred;
+
+	if (cred_p == NULL || (cred = *cred_p) == NULL)
+		return;
+	fido_cred_reset_tx(cred);
+	fido_cred_reset_rx(cred);
+	free(cred);
+	*cred_p = NULL;
+}
+
+int
+fido_cred_set_authdata(fido_cred_t *cred, const unsigned char *ptr, size_t len)
+{
+	cbor_item_t		*item = NULL;
+	struct cbor_load_result	 cbor;
+	int			 r = FIDO_ERR_INVALID_ARGUMENT;
+
+	fido_cred_clean_authdata(cred);
+
+	if (ptr == NULL || len == 0)
+		goto fail;
+
+	if ((item = cbor_load(ptr, len, &cbor)) == NULL) {
+		fido_log_debug("%s: cbor_load", __func__);
+		goto fail;
+	}
+
+	if (fido_blob_decode(item, &cred->authdata_raw) < 0) {
+		fido_log_debug("%s: fido_blob_decode", __func__);
+		goto fail;
+	}
+
+	if (cbor_decode_cred_authdata(item, cred->type, &cred->authdata_cbor,
+	    &cred->authdata, &cred->attcred, &cred->authdata_ext) < 0) {
+		fido_log_debug("%s: cbor_decode_cred_authdata", __func__);
+		goto fail;
+	}
+
+	r = FIDO_OK;
+fail:
+	if (item != NULL)
+		cbor_decref(&item);
+
+	if (r != FIDO_OK)
+		fido_cred_clean_authdata(cred);
+
+	return (r);
+}
+
+int
+fido_cred_set_authdata_raw(fido_cred_t *cred, const unsigned char *ptr,
+    size_t len)
+{
+	cbor_item_t	*item = NULL;
+	int		 r = FIDO_ERR_INVALID_ARGUMENT;
+
+	fido_cred_clean_authdata(cred);
+
+	if (ptr == NULL || len == 0)
+		goto fail;
+
+	if (fido_blob_set(&cred->authdata_raw, ptr, len) < 0) {
+		fido_log_debug("%s: fido_blob_set", __func__);
+		r = FIDO_ERR_INTERNAL;
+		goto fail;
+	}
+
+	if ((item = cbor_build_bytestring(ptr, len)) == NULL) {
+		fido_log_debug("%s: cbor_build_bytestring", __func__);
+		r = FIDO_ERR_INTERNAL;
+		goto fail;
+	}
+
+	if (cbor_decode_cred_authdata(item, cred->type, &cred->authdata_cbor,
+	    &cred->authdata, &cred->attcred, &cred->authdata_ext) < 0) {
+		fido_log_debug("%s: cbor_decode_cred_authdata", __func__);
+		goto fail;
+	}
+
+	r = FIDO_OK;
+fail:
+	if (item != NULL)
+		cbor_decref(&item);
+
+	if (r != FIDO_OK)
+		fido_cred_clean_authdata(cred);
+
+	return (r);
+}
+
+int
+fido_cred_set_id(fido_cred_t *cred, const unsigned char *ptr, size_t len)
+{
+	if (fido_blob_set(&cred->attcred.id, ptr, len) < 0)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_x509(fido_cred_t *cred, const unsigned char *ptr, size_t len)
+{
+	if (fido_blob_set(&cred->attstmt.x5c, ptr, len) < 0)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_sig(fido_cred_t *cred, const unsigned char *ptr, size_t len)
+{
+	if (fido_blob_set(&cred->attstmt.sig, ptr, len) < 0)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_attstmt(fido_cred_t *cred, const unsigned char *ptr, size_t len)
+{
+	cbor_item_t		*item = NULL;
+	struct cbor_load_result	 cbor;
+	int			 r = FIDO_ERR_INVALID_ARGUMENT;
+
+	fido_cred_clean_attstmt(&cred->attstmt);
+
+	if (ptr == NULL || len == 0)
+		goto fail;
+
+	if ((item = cbor_load(ptr, len, &cbor)) == NULL) {
+		fido_log_debug("%s: cbor_load", __func__);
+		goto fail;
+	}
+
+	if (cbor_decode_attstmt(item, &cred->attstmt) < 0) {
+		fido_log_debug("%s: cbor_decode_attstmt", __func__);
+		goto fail;
+	}
+
+	r = FIDO_OK;
+fail:
+	if (item != NULL)
+		cbor_decref(&item);
+
+	if (r != FIDO_OK)
+		fido_cred_clean_attstmt(&cred->attstmt);
+
+	return (r);
+}
+
+int
+fido_cred_exclude(fido_cred_t *cred, const unsigned char *id_ptr, size_t id_len)
+{
+	fido_blob_t id_blob;
+	fido_blob_t *list_ptr;
+
+	memset(&id_blob, 0, sizeof(id_blob));
+
+	if (fido_blob_set(&id_blob, id_ptr, id_len) < 0)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	if (cred->excl.len == SIZE_MAX) {
+		free(id_blob.ptr);
+		return (FIDO_ERR_INVALID_ARGUMENT);
+	}
+
+	if ((list_ptr = recallocarray(cred->excl.ptr, cred->excl.len,
+	    cred->excl.len + 1, sizeof(fido_blob_t))) == NULL) {
+		free(id_blob.ptr);
+		return (FIDO_ERR_INTERNAL);
+	}
+
+	list_ptr[cred->excl.len++] = id_blob;
+	cred->excl.ptr = list_ptr;
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_empty_exclude_list(fido_cred_t *cred)
+{
+	fido_free_blob_array(&cred->excl);
+	memset(&cred->excl, 0, sizeof(cred->excl));
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_clientdata(fido_cred_t *cred, const unsigned char *data,
+    size_t data_len)
+{
+	if (!fido_blob_is_empty(&cred->cdh) ||
+	    fido_blob_set(&cred->cd, data, data_len) < 0) {
+		return (FIDO_ERR_INVALID_ARGUMENT);
+	}
+	if (fido_sha256(&cred->cdh, data, data_len) < 0) {
+		fido_blob_reset(&cred->cd);
+		return (FIDO_ERR_INTERNAL);
+	}
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_clientdata_hash(fido_cred_t *cred, const unsigned char *hash,
+    size_t hash_len)
+{
+	if (!fido_blob_is_empty(&cred->cd) ||
+	    fido_blob_set(&cred->cdh, hash, hash_len) < 0)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_rp(fido_cred_t *cred, const char *id, const char *name)
+{
+	fido_rp_t *rp = &cred->rp;
+
+	if (rp->id != NULL) {
+		free(rp->id);
+		rp->id = NULL;
+	}
+	if (rp->name != NULL) {
+		free(rp->name);
+		rp->name = NULL;
+	}
+
+	if (id != NULL && (rp->id = strdup(id)) == NULL)
+		goto fail;
+	if (name != NULL && (rp->name = strdup(name)) == NULL)
+		goto fail;
+
+	return (FIDO_OK);
+fail:
+	free(rp->id);
+	free(rp->name);
+	rp->id = NULL;
+	rp->name = NULL;
+
+	return (FIDO_ERR_INTERNAL);
+}
+
+int
+fido_cred_set_user(fido_cred_t *cred, const unsigned char *user_id,
+    size_t user_id_len, const char *name, const char *display_name,
+    const char *icon)
+{
+	fido_user_t *up = &cred->user;
+
+	if (up->id.ptr != NULL) {
+		free(up->id.ptr);
+		up->id.ptr = NULL;
+		up->id.len = 0;
+	}
+	if (up->name != NULL) {
+		free(up->name);
+		up->name = NULL;
+	}
+	if (up->display_name != NULL) {
+		free(up->display_name);
+		up->display_name = NULL;
+	}
+	if (up->icon != NULL) {
+		free(up->icon);
+		up->icon = NULL;
+	}
+
+	if (user_id != NULL && fido_blob_set(&up->id, user_id, user_id_len) < 0)
+		goto fail;
+	if (name != NULL && (up->name = strdup(name)) == NULL)
+		goto fail;
+	if (display_name != NULL &&
+	    (up->display_name = strdup(display_name)) == NULL)
+		goto fail;
+	if (icon != NULL && (up->icon = strdup(icon)) == NULL)
+		goto fail;
+
+	return (FIDO_OK);
+fail:
+	free(up->id.ptr);
+	free(up->name);
+	free(up->display_name);
+	free(up->icon);
+
+	up->id.ptr = NULL;
+	up->id.len = 0;
+	up->name = NULL;
+	up->display_name = NULL;
+	up->icon = NULL;
+
+	return (FIDO_ERR_INTERNAL);
+}
+
+int
+fido_cred_set_extensions(fido_cred_t *cred, int ext)
+{
+	if (ext == 0)
+		cred->ext.mask = 0;
+	else {
+		if ((ext & FIDO_EXT_CRED_MASK) != ext)
+			return (FIDO_ERR_INVALID_ARGUMENT);
+		cred->ext.mask |= ext;
+	}
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_options(fido_cred_t *cred, bool rk, bool uv)
+{
+	cred->rk = rk ? FIDO_OPT_TRUE : FIDO_OPT_FALSE;
+	cred->uv = uv ? FIDO_OPT_TRUE : FIDO_OPT_FALSE;
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_rk(fido_cred_t *cred, fido_opt_t rk)
+{
+	cred->rk = rk;
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_uv(fido_cred_t *cred, fido_opt_t uv)
+{
+	cred->uv = uv;
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_prot(fido_cred_t *cred, int prot)
+{
+	if (prot == 0) {
+		cred->ext.mask &= ~FIDO_EXT_CRED_PROTECT;
+		cred->ext.prot = 0;
+	} else {
+		if (prot != FIDO_CRED_PROT_UV_OPTIONAL &&
+		    prot != FIDO_CRED_PROT_UV_OPTIONAL_WITH_ID &&
+		    prot != FIDO_CRED_PROT_UV_REQUIRED)
+			return (FIDO_ERR_INVALID_ARGUMENT);
+
+		cred->ext.mask |= FIDO_EXT_CRED_PROTECT;
+		cred->ext.prot = prot;
+	}
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_pin_minlen(fido_cred_t *cred, size_t len)
+{
+	if (len == 0)
+		cred->ext.mask &= ~FIDO_EXT_MINPINLEN;
+	else
+		cred->ext.mask |= FIDO_EXT_MINPINLEN;
+
+	cred->ext.minpinlen = len;
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_blob(fido_cred_t *cred, const unsigned char *ptr, size_t len)
+{
+	if (ptr == NULL || len == 0)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+	if (fido_blob_set(&cred->blob, ptr, len) < 0)
+		return (FIDO_ERR_INTERNAL);
+
+	cred->ext.mask |= FIDO_EXT_CRED_BLOB;
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_fmt(fido_cred_t *cred, const char *fmt)
+{
+	free(cred->fmt);
+	cred->fmt = NULL;
+
+	if (fmt == NULL)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	if (strcmp(fmt, "packed") && strcmp(fmt, "fido-u2f") &&
+	    strcmp(fmt, "none") && strcmp(fmt, "tpm"))
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	if ((cred->fmt = strdup(fmt)) == NULL)
+		return (FIDO_ERR_INTERNAL);
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_set_type(fido_cred_t *cred, int cose_alg)
+{
+	if (cred->type != 0)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+	if (cose_alg != COSE_ES256 && cose_alg != COSE_ES384 &&
+	    cose_alg != COSE_RS256 && cose_alg != COSE_EDDSA)
+		return (FIDO_ERR_INVALID_ARGUMENT);
+
+	cred->type = cose_alg;
+
+	return (FIDO_OK);
+}
+
+int
+fido_cred_type(const fido_cred_t *cred)
+{
+	return (cred->type);
+}
+
+uint8_t
+fido_cred_flags(const fido_cred_t *cred)
+{
+	return (cred->authdata.flags);
+}
+
+uint32_t
+fido_cred_sigcount(const fido_cred_t *cred)
+{
+	return (cred->authdata.sigcount);
+}
+
+const unsigned char *
+fido_cred_clientdata_hash_ptr(const fido_cred_t *cred)
+{
+	return (cred->cdh.ptr);
+}
+
+size_t
+fido_cred_clientdata_hash_len(const fido_cred_t *cred)
+{
+	return (cred->cdh.len);
+}
+
+const unsigned char *
+fido_cred_x5c_ptr(const fido_cred_t *cred)
+{
+	return (cred->attstmt.x5c.ptr);
+}
+
+size_t
+fido_cred_x5c_len(const fido_cred_t *cred)
+{
+	return (cred->attstmt.x5c.len);
+}
+
+const unsigned char *
+fido_cred_sig_ptr(const fido_cred_t *cred)
+{
+	return (cred->attstmt.sig.ptr);
+}
+
+size_t
+fido_cred_sig_len(const fido_cred_t *cred)
+{
+	return (cred->attstmt.sig.len);
+}
+
+const unsigned char *
+fido_cred_authdata_ptr(const fido_cred_t *cred)
+{
+	return (cred->authdata_cbor.ptr);
+}
+
+size_t
+fido_cred_authdata_len(const fido_cred_t *cred)
+{
+	return (cred->authdata_cbor.len);
+}
+
+const unsigned char *
+fido_cred_authdata_raw_ptr(const fido_cred_t *cred)
+{
+	return (cred->authdata_raw.ptr);
+}
+
+size_t
+fido_cred_authdata_raw_len(const fido_cred_t *cred)
+{
+	return (cred->authdata_raw.len);
+}
+
+const unsigned char *
+fido_cred_attstmt_ptr(const fido_cred_t *cred)
+{
+	return (cred->attstmt.cbor.ptr);
+}
+
+size_t
+fido_cred_attstmt_len(const fido_cred_t *cred)
+{
+	return (cred->attstmt.cbor.len);
+}
+
+const unsigned char *
+fido_cred_pubkey_ptr(const fido_cred_t *cred)
+{
+	const void *ptr;
+
+	switch (cred->attcred.type) {
+	case COSE_ES256:
+		ptr = &cred->attcred.pubkey.es256;
+		break;
+	case COSE_ES384:
+		ptr = &cred->attcred.pubkey.es384;
+		break;
+	case COSE_RS256:
+		ptr = &cred->attcred.pubkey.rs256;
+		break;
+	case COSE_EDDSA:
+		ptr = &cred->attcred.pubkey.eddsa;
+		break;
+	default:
+		ptr = NULL;
+		break;
+	}
+
+	return (ptr);
+}
+
+size_t
+fido_cred_pubkey_len(const fido_cred_t *cred)
+{
+	size_t len;
+
+	switch (cred->attcred.type) {
+	case COSE_ES256:
+		len = sizeof(cred->attcred.pubkey.es256);
+		break;
+	case COSE_ES384:
+		len = sizeof(cred->attcred.pubkey.es384);
+		break;
+	case COSE_RS256:
+		len = sizeof(cred->attcred.pubkey.rs256);
+		break;
+	case COSE_EDDSA:
+		len = sizeof(cred->attcred.pubkey.eddsa);
+		break;
+	default:
+		len = 0;
+		break;
+	}
+
+	return (len);
+}
+
+const unsigned char *
+fido_cred_id_ptr(const fido_cred_t *cred)
+{
+	return (cred->attcred.id.ptr);
+}
+
+size_t
+fido_cred_id_len(const fido_cred_t *cred)
+{
+	return (cred->attcred.id.len);
+}
+
+const unsigned char *
+fido_cred_aaguid_ptr(const fido_cred_t *cred)
+{
+	return (cred->attcred.aaguid);
+}
+
+size_t
+fido_cred_aaguid_len(const fido_cred_t *cred)
+{
+	return (sizeof(cred->attcred.aaguid));
+}
+
+int
+fido_cred_prot(const fido_cred_t *cred)
+{
+	return (cred->ext.prot);
+}
+
+size_t
+fido_cred_pin_minlen(const fido_cred_t *cred)
+{
+	return (cred->ext.minpinlen);
+}
+
+const char *
+fido_cred_fmt(const fido_cred_t *cred)
+{
+	return (cred->fmt);
+}
+
+const char *
+fido_cred_rp_id(const fido_cred_t *cred)
+{
+	return (cred->rp.id);
+}
+
+const char *
+fido_cred_rp_name(const fido_cred_t *cred)
+{
+	return (cred->rp.name);
+}
+
+const char *
+fido_cred_user_name(const fido_cred_t *cred)
+{
+	return (cred->user.name);
+}
+
+const char *
+fido_cred_display_name(const fido_cred_t *cred)
+{
+	return (cred->user.display_name);
+}
+
+const unsigned char *
+fido_cred_user_id_ptr(const fido_cred_t *cred)
+{
+	return (cred->user.id.ptr);
+}
+
+size_t
+fido_cred_user_id_len(const fido_cred_t *cred)
+{
+	return (cred->user.id.len);
+}
+
+const unsigned char *
+fido_cred_largeblob_key_ptr(const fido_cred_t *cred)
+{
+	return (cred->largeblob_key.ptr);
+}
+
+size_t
+fido_cred_largeblob_key_len(const fido_cred_t *cred)
+{
+	return (cred->largeblob_key.len);
+}