New upstream version 1.3.1

2 files changed, 0 insertions, 791 deletions

diff --git a/tools/CMakeLists.txt b/tools/CMakeLists.txt
index 5f27e88..4b8ef32 100644
--- a/tools/CMakeLists.txt
+++ b/tools/CMakeLists.txt
@@ -49,17 +49,10 @@ add_executable(fido2-token
         ${COMPAT_SOURCES}
 )
 
-add_library(sk-libfido2 MODULE sk-libfido2.c)
-set_target_properties(sk-libfido2 PROPERTIES
-        COMPILE_FLAGS "-DSK_STANDALONE -DWITH_OPENSSL"
-        OUTPUT_NAME sk-libfido2
-)
 
 target_link_libraries(fido2-cred ${CRYPTO_LIBRARIES} fido2_shared)
 target_link_libraries(fido2-assert ${CRYPTO_LIBRARIES} fido2_shared)
 target_link_libraries(fido2-token ${CRYPTO_LIBRARIES} fido2_shared)
-target_link_libraries(sk-libfido2 ${CRYPTO_LIBRARIES} fido2_shared)
 
 install(TARGETS fido2-cred fido2-assert fido2-token
         DESTINATION ${CMAKE_INSTALL_BINDIR})
-install(TARGETS sk-libfido2 DESTINATION ${CMAKE_INSTALL_LIBDIR})
diff --git a/tools/sk-libfido2.c b/tools/sk-libfido2.c
deleted file mode 100644
index 15aa813..0000000
--- a/tools/sk-libfido2.c
+++ /dev/null
@@ -1,784 +0,0 @@
-/*
- * Copyright (c) 2019 Markus Friedl
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-
-#include <fcntl.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-#include <stddef.h>
-#include <stdarg.h>
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-
-#ifdef WITH_OPENSSL
-#include <openssl/opensslv.h>
-#include <openssl/crypto.h>
-#include <openssl/bn.h>
-#include <openssl/ec.h>
-#include <openssl/ecdsa.h>
-#endif /* WITH_OPENSSL */
-
-#include <fido.h>
-
-#ifndef SK_STANDALONE
-#include "log.h"
-#include "xmalloc.h"
-#endif
-
-/* #define SK_DEBUG 1 */
-
-#if defined(_WIN32)
-#include <windows.h>
-#include <winternl.h>
-#include <winerror.h>
-#include <bcrypt.h>
-#include <sal.h>
-#endif 
-
-#define MAX_FIDO_DEVICES        256
-
-/* Compatibility with OpenSSL 1.0.x */
-#if (OPENSSL_VERSION_NUMBER < 0x10100000L)
-#define ECDSA_SIG_get0(sig, pr, ps) \
-        do { \
-                (*pr) = sig->r; \
-                (*ps) = sig->s; \
-        } while (0)
-#endif
-
-#define SK_VERSION_MAJOR        0x00020000 /* current API version */
-
-/* Flags */
-#define SK_USER_PRESENCE_REQD   0x01
-
-/* Algs */
-#define SK_ECDSA                0x00
-#define SK_ED25519              0x01
-
-struct sk_enroll_response {
-        uint8_t *public_key;
-        size_t public_key_len;
-        uint8_t *key_handle;
-        size_t key_handle_len;
-        uint8_t *signature;
-        size_t signature_len;
-        uint8_t *attestation_cert;
-        size_t attestation_cert_len;
-};
-
-struct sk_sign_response {
-        uint8_t flags;
-        uint32_t counter;
-        uint8_t *sig_r;
-        size_t sig_r_len;
-        uint8_t *sig_s;
-        size_t sig_s_len;
-};
-
-/* If building as part of OpenSSH, then rename exported functions */
-#if !defined(SK_STANDALONE)
-#define sk_api_version  ssh_sk_api_version
-#define sk_enroll       ssh_sk_enroll
-#define sk_sign         ssh_sk_sign
-#endif
-
-/* Return the version of the middleware API */
-uint32_t sk_api_version(void);
-
-/* Enroll a U2F key (private key generation) */
-int sk_enroll(int alg, const uint8_t *challenge, size_t challenge_len,
-    const char *application, uint8_t flags,
-    struct sk_enroll_response **enroll_response);
-
-/* Sign a challenge */
-int sk_sign(int alg, const uint8_t *message, size_t message_len,
-    const char *application, const uint8_t *key_handle, size_t key_handle_len,
-    uint8_t flags, struct sk_sign_response **sign_response);
-
-#ifdef SK_DEBUG
-static void skdebug(const char *func, const char *fmt, ...)
-    __attribute__((__format__ (printf, 2, 3)));
-
-static void
-skdebug(const char *func, const char *fmt, ...)
-{
-#if !defined(SK_STANDALONE)
-        char *msg;
-        va_list ap;
-
-        va_start(ap, fmt);
-        xvasprintf(&msg, fmt, ap);
-        va_end(ap);
-        debug("%s: %s", func, msg);
-        free(msg);
-#else
-        va_list ap;
-
-        va_start(ap, fmt);
-        fprintf(stderr, "%s: ", func);
-        vfprintf(stderr, fmt, ap);
-        fputc('\n', stderr);
-        va_end(ap);
-#endif /* !SK_STANDALONE */
-}
-#else
-#define skdebug(...) do { /* nothing */ } while (0)
-#endif /* SK_DEBUG */
-
-uint32_t
-sk_api_version(void)
-{
-        return SK_VERSION_MAJOR;
-}
-
-/* Select the first identified FIDO device attached to the system */
-static char *
-pick_first_device(void)
-{
-        char *ret = NULL;
-        fido_dev_info_t *devlist = NULL;
-        size_t olen = 0;
-        int r;
-        const fido_dev_info_t *di;
-
-        if ((devlist = fido_dev_info_new(1)) == NULL) {
-                skdebug(__func__, "fido_dev_info_new failed");
-                goto out;
-        }
-        if ((r = fido_dev_info_manifest(devlist, 1, &olen)) != FIDO_OK) {
-                skdebug(__func__, "fido_dev_info_manifest failed: %s",
-                    fido_strerr(r));
-                goto out;
-        }
-        if (olen != 1) {
-                skdebug(__func__, "fido_dev_info_manifest bad len %zu", olen);
-                goto out;
-        }
-        di = fido_dev_info_ptr(devlist, 0);
-        if ((ret = strdup(fido_dev_info_path(di))) == NULL) {
-                skdebug(__func__, "fido_dev_info_path failed");
-                goto out;
-        }
- out:
-        fido_dev_info_free(&devlist, 1);
-        return ret;
-}
-
-#if defined(HAVE_ARC4RANDOM_BUF)
-static int
-get_random_challenge(uint8_t *ptr, size_t len)
-{
-        arc4random_buf(ptr, len);
-
-        return 0;
-}
-#elif defined(HAVE_GETENTROPY)
-static int
-get_random_challenge(uint8_t *ptr, size_t len)
-{
-        if (getentropy(ptr, len) == -1) {
-                skdebug(__func__, "getentropy failed");
-                return -1;
-        }
-
-        return 0;
-}
-#elif defined(HAS_DEV_URANDOM)
-static int
-get_random_challenge(uint8_t *ptr, size_t len)
-{
-        int fd;
-        ssize_t n;
-
-        if ((fd = open(FIDO_RANDOM_DEV, O_RDONLY)) < 0) {
-                skdebug(__func__, "open %s failed", FIDO_RANDOM_DEV);
-                return -1;
-        }
-
-        n = read(fd, ptr, len);
-        close(fd);
-
-        if (n < 0 || (size_t)n != len) {
-                skdebug(__func__, "read from %s failed", FIDO_RANDOM_DEV);
-                return -1;
-        }
-
-        return 0;
-}
-#elif defined(_WIN32)
-static int
-get_random_challenge(uint8_t *ptr, size_t len)
-{
-        NTSTATUS status;
-
-        status = BCryptGenRandom(NULL, ptr, len,
-            BCRYPT_USE_SYSTEM_PREFERRED_RNG);
-        if (!NT_SUCCESS(status))
-                return -1;
-
-        return 0;
-}
-#else
-#error "please provide an implementation of get_random_challenge() for your platform"
-#endif
-
-/* Check if the specified key handle exists on a given device. */
-static int
-try_device(fido_dev_t *dev, const char *application,
-    const uint8_t *key_handle, size_t key_handle_len)
-{
-        fido_assert_t *assert = NULL;
-        uint8_t challenge[32];
-        int r = FIDO_ERR_INTERNAL;
-
-        if (get_random_challenge(challenge, sizeof(challenge)) == -1) {
-                skdebug(__func__, "get_random_challenge failed");
-                goto out;
-        }
-
-        if ((assert = fido_assert_new()) == NULL) {
-                skdebug(__func__, "fido_assert_new failed");
-                goto out;
-        }
-        if ((r = fido_assert_set_clientdata_hash(assert, challenge,
-            sizeof(challenge))) != FIDO_OK) {
-                skdebug(__func__, "fido_assert_set_clientdata_hash: %s",
-                    fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_assert_set_rp(assert, application)) != FIDO_OK) {
-                skdebug(__func__, "fido_assert_set_rp: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_assert_allow_cred(assert, key_handle,
-            key_handle_len)) != FIDO_OK) {
-                skdebug(__func__, "fido_assert_allow_cred: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_assert_set_up(assert, FIDO_OPT_FALSE)) != FIDO_OK) {
-                skdebug(__func__, "fido_assert_up: %s", fido_strerr(r));
-                goto out;
-        }
-        r = fido_dev_get_assert(dev, assert, NULL);
-        skdebug(__func__, "fido_dev_get_assert: %s", fido_strerr(r));
-        if (r == FIDO_ERR_USER_PRESENCE_REQUIRED) {
-                /* U2F tokens may return this */
-                r = FIDO_OK;
-        }
- out:
-        fido_assert_free(&assert);
-
-        return r != FIDO_OK ? -1 : 0;
-}
-
-/* Iterate over configured devices looking for a specific key handle */
-static fido_dev_t *
-find_device(const char *application, const uint8_t *key_handle,
-    size_t key_handle_len)
-{
-        fido_dev_info_t *devlist = NULL;
-        fido_dev_t *dev = NULL;
-        size_t devlist_len = 0, i;
-        const char *path;
-        int r;
-
-        if ((devlist = fido_dev_info_new(MAX_FIDO_DEVICES)) == NULL) {
-                skdebug(__func__, "fido_dev_info_new failed");
-                goto out;
-        }
-        if ((r = fido_dev_info_manifest(devlist, MAX_FIDO_DEVICES,
-            &devlist_len)) != FIDO_OK) {
-                skdebug(__func__, "fido_dev_info_manifest: %s", fido_strerr(r));
-                goto out;
-        }
-
-        skdebug(__func__, "found %zu device(s)", devlist_len);
-
-        for (i = 0; i < devlist_len; i++) {
-                const fido_dev_info_t *di = fido_dev_info_ptr(devlist, i);
-
-                if (di == NULL) {
-                        skdebug(__func__, "fido_dev_info_ptr %zu failed", i);
-                        continue;
-                }
-                if ((path = fido_dev_info_path(di)) == NULL) {
-                        skdebug(__func__, "fido_dev_info_path %zu failed", i);
-                        continue;
-                }
-                skdebug(__func__, "trying device %zu: %s", i, path);
-                if ((dev = fido_dev_new()) == NULL) {
-                        skdebug(__func__, "fido_dev_new failed");
-                        continue;
-                }
-                if ((r = fido_dev_open(dev, path)) != FIDO_OK) {
-                        skdebug(__func__, "fido_dev_open failed");
-                        fido_dev_free(&dev);
-                        continue;
-                }
-                if (try_device(dev, application, key_handle,
-                    key_handle_len) == 0) {
-                        skdebug(__func__, "found key");
-                        break;
-                }
-                fido_dev_close(dev);
-                fido_dev_free(&dev);
-        }
-
- out:
-        if (devlist != NULL)
-                fido_dev_info_free(&devlist, MAX_FIDO_DEVICES);
-
-        return dev;
-}
-
-#ifdef WITH_OPENSSL
-/*
- * The key returned via fido_cred_pubkey_ptr() is in affine coordinates,
- * but the API expects a SEC1 octet string.
- */
-static int
-pack_public_key_ecdsa(fido_cred_t *cred, struct sk_enroll_response *response)
-{
-        const uint8_t *ptr;
-        BIGNUM *x = NULL, *y = NULL;
-        EC_POINT *q = NULL;
-        EC_GROUP *g = NULL;
-        int ret = -1;
-
-        response->public_key = NULL;
-        response->public_key_len = 0;
-
-        if ((x = BN_new()) == NULL ||
-            (y = BN_new()) == NULL ||
-            (g = EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1)) == NULL ||
-            (q = EC_POINT_new(g)) == NULL) {
-                skdebug(__func__, "libcrypto setup failed");
-                goto out;
-        }
-        if ((ptr = fido_cred_pubkey_ptr(cred)) == NULL) {
-                skdebug(__func__, "fido_cred_pubkey_ptr failed");
-                goto out;
-        }
-        if (fido_cred_pubkey_len(cred) != 64) {
-                skdebug(__func__, "bad fido_cred_pubkey_len %zu",
-                    fido_cred_pubkey_len(cred));
-                goto out;
-        }
-
-        if (BN_bin2bn(ptr, 32, x) == NULL ||
-            BN_bin2bn(ptr + 32, 32, y) == NULL) {
-                skdebug(__func__, "BN_bin2bn failed");
-                goto out;
-        }
-        if (EC_POINT_set_affine_coordinates_GFp(g, q, x, y, NULL) != 1) {
-                skdebug(__func__, "EC_POINT_set_affine_coordinates_GFp failed");
-                goto out;
-        }
-        response->public_key_len = EC_POINT_point2oct(g, q,
-            POINT_CONVERSION_UNCOMPRESSED, NULL, 0, NULL);
-        if (response->public_key_len == 0 || response->public_key_len > 2048) {
-                skdebug(__func__, "bad pubkey length %zu",
-                    response->public_key_len);
-                goto out;
-        }
-        if ((response->public_key = malloc(response->public_key_len)) == NULL) {
-                skdebug(__func__, "malloc pubkey failed");
-                goto out;
-        }
-        if (EC_POINT_point2oct(g, q, POINT_CONVERSION_UNCOMPRESSED,
-            response->public_key, response->public_key_len, NULL) == 0) {
-                skdebug(__func__, "EC_POINT_point2oct failed");
-                goto out;
-        }
-        /* success */
-        ret = 0;
- out:
-        if (ret != 0 && response->public_key != NULL) {
-                memset(response->public_key, 0, response->public_key_len);
-                free(response->public_key);
-                response->public_key = NULL;
-        }
-        EC_POINT_free(q);
-        EC_GROUP_free(g);
-        BN_clear_free(x);
-        BN_clear_free(y);
-        return ret;
-}
-#endif /* WITH_OPENSSL */
-
-static int
-pack_public_key_ed25519(fido_cred_t *cred, struct sk_enroll_response *response)
-{
-        const uint8_t *ptr;
-        size_t len;
-        int ret = -1;
-
-        response->public_key = NULL;
-        response->public_key_len = 0;
-
-        if ((len = fido_cred_pubkey_len(cred)) != 32) {
-                skdebug(__func__, "bad fido_cred_pubkey_len len %zu", len);
-                goto out;
-        }
-        if ((ptr = fido_cred_pubkey_ptr(cred)) == NULL) {
-                skdebug(__func__, "fido_cred_pubkey_ptr failed");
-                goto out;
-        }
-        response->public_key_len = len;
-        if ((response->public_key = malloc(response->public_key_len)) == NULL) {
-                skdebug(__func__, "malloc pubkey failed");
-                goto out;
-        }
-        memcpy(response->public_key, ptr, len);
-        ret = 0;
- out:
-        if (ret != 0)
-                free(response->public_key);
-        return ret;
-}
-
-static int
-pack_public_key(int alg, fido_cred_t *cred, struct sk_enroll_response *response)
-{
-        switch(alg) {
-#ifdef WITH_OPENSSL
-        case SK_ECDSA:
-                return pack_public_key_ecdsa(cred, response);
-#endif /* WITH_OPENSSL */
-        case SK_ED25519:
-                return pack_public_key_ed25519(cred, response);
-        default:
-                return -1;
-        }
-}
-
-int
-sk_enroll(int alg, const uint8_t *challenge, size_t challenge_len,
-    const char *application, uint8_t flags,
-    struct sk_enroll_response **enroll_response)
-{
-        fido_cred_t *cred = NULL;
-        fido_dev_t *dev = NULL;
-        const uint8_t *ptr;
-        uint8_t user_id[32];
-        struct sk_enroll_response *response = NULL;
-        size_t len;
-        int cose_alg;
-        int ret = -1;
-        int r;
-        char *device = NULL;
-
-        (void)flags; /* XXX; unused */
-#ifdef SK_DEBUG
-        fido_init(FIDO_DEBUG);
-#endif
-        if (enroll_response == NULL) {
-                skdebug(__func__, "enroll_response == NULL");
-                goto out;
-        }
-        *enroll_response = NULL;
-        switch(alg) {
-#ifdef WITH_OPENSSL
-        case SK_ECDSA:
-                cose_alg = COSE_ES256;
-                break;
-#endif /* WITH_OPENSSL */
-        case SK_ED25519:
-                cose_alg = COSE_EDDSA;
-                break;
-        default:
-                skdebug(__func__, "unsupported key type %d", alg);
-                goto out;
-        }
-        if ((device = pick_first_device()) == NULL) {
-                skdebug(__func__, "pick_first_device failed");
-                goto out;
-        }
-        skdebug(__func__, "using device %s", device);
-        if ((cred = fido_cred_new()) == NULL) {
-                skdebug(__func__, "fido_cred_new failed");
-                goto out;
-        }
-        memset(user_id, 0, sizeof(user_id));
-        if ((r = fido_cred_set_type(cred, cose_alg)) != FIDO_OK) {
-                skdebug(__func__, "fido_cred_set_type: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_cred_set_clientdata_hash(cred, challenge,
-            challenge_len)) != FIDO_OK) {
-                skdebug(__func__, "fido_cred_set_clientdata_hash: %s",
-                    fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_cred_set_user(cred, user_id, sizeof(user_id),
-            "openssh", "openssh", NULL)) != FIDO_OK) {
-                skdebug(__func__, "fido_cred_set_user: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_cred_set_rp(cred, application, NULL)) != FIDO_OK) {
-                skdebug(__func__, "fido_cred_set_rp: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((dev = fido_dev_new()) == NULL) {
-                skdebug(__func__, "fido_dev_new failed");
-                goto out;
-        }
-        if ((r = fido_dev_open(dev, device)) != FIDO_OK) {
-                skdebug(__func__, "fido_dev_open: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_dev_make_cred(dev, cred, NULL)) != FIDO_OK) {
-                skdebug(__func__, "fido_dev_make_cred: %s", fido_strerr(r));
-                goto out;
-        }
-        if (fido_cred_x5c_ptr(cred) != NULL) {
-                if ((r = fido_cred_verify(cred)) != FIDO_OK) {
-                        skdebug(__func__, "fido_cred_verify: %s",
-                            fido_strerr(r));
-                        goto out;
-                }
-        } else {
-                skdebug(__func__, "self-attested credential");
-                if ((r = fido_cred_verify_self(cred)) != FIDO_OK) {
-                        skdebug(__func__, "fido_cred_verify_self: %s",
-                            fido_strerr(r));
-                        goto out;
-                }
-        }
-        if ((response = calloc(1, sizeof(*response))) == NULL) {
-                skdebug(__func__, "calloc response failed");
-                goto out;
-        }
-        if (pack_public_key(alg, cred, response) != 0) {
-                skdebug(__func__, "pack_public_key failed");
-                goto out;
-        }
-        if ((ptr = fido_cred_id_ptr(cred)) != NULL) {
-                len = fido_cred_id_len(cred);
-                if ((response->key_handle = calloc(1, len)) == NULL) {
-                        skdebug(__func__, "calloc key handle failed");
-                        goto out;
-                }
-                memcpy(response->key_handle, ptr, len);
-                response->key_handle_len = len;
-        }
-        if ((ptr = fido_cred_sig_ptr(cred)) != NULL) {
-                len = fido_cred_sig_len(cred);
-                if ((response->signature = calloc(1, len)) == NULL) {
-                        skdebug(__func__, "calloc signature failed");
-                        goto out;
-                }
-                memcpy(response->signature, ptr, len);
-                response->signature_len = len;
-        }
-        if ((ptr = fido_cred_x5c_ptr(cred)) != NULL) {
-                len = fido_cred_x5c_len(cred);
-                if ((response->attestation_cert = calloc(1, len)) == NULL) {
-                        skdebug(__func__, "calloc attestation cert failed");
-                        goto out;
-                }
-                memcpy(response->attestation_cert, ptr, len);
-                response->attestation_cert_len = len;
-        }
-        *enroll_response = response;
-        response = NULL;
-        ret = 0;
- out:
-        free(device);
-        if (response != NULL) {
-                free(response->public_key);
-                free(response->key_handle);
-                free(response->signature);
-                free(response->attestation_cert);
-                free(response);
-        }
-        if (dev != NULL) {
-                fido_dev_close(dev);
-                fido_dev_free(&dev);
-        }
-        if (cred != NULL) {
-                fido_cred_free(&cred);
-        }
-        return ret;
-}
-
-#ifdef WITH_OPENSSL
-static int
-pack_sig_ecdsa(fido_assert_t *assert, struct sk_sign_response *response)
-{
-        ECDSA_SIG *sig = NULL;
-        const BIGNUM *sig_r, *sig_s;
-        const unsigned char *cp;
-        size_t sig_len;
-        int ret = -1;
-
-        cp = fido_assert_sig_ptr(assert, 0);
-        sig_len = fido_assert_sig_len(assert, 0);
-        if ((sig = d2i_ECDSA_SIG(NULL, &cp, sig_len)) == NULL) {
-                skdebug(__func__, "d2i_ECDSA_SIG failed");
-                goto out;
-        }
-        ECDSA_SIG_get0(sig, &sig_r, &sig_s);
-        response->sig_r_len = BN_num_bytes(sig_r);
-        response->sig_s_len = BN_num_bytes(sig_s);
-        if ((response->sig_r = calloc(1, response->sig_r_len)) == NULL ||
-            (response->sig_s = calloc(1, response->sig_s_len)) == NULL) {
-                skdebug(__func__, "calloc signature failed");
-                goto out;
-        }
-        BN_bn2bin(sig_r, response->sig_r);
-        BN_bn2bin(sig_s, response->sig_s);
-        ret = 0;
- out:
-        ECDSA_SIG_free(sig);
-        if (ret != 0) {
-                free(response->sig_r);
-                free(response->sig_s);
-                response->sig_r = NULL;
-                response->sig_s = NULL;
-        }
-        return ret;
-}
-#endif /* WITH_OPENSSL */
-
-static int
-pack_sig_ed25519(fido_assert_t *assert, struct sk_sign_response *response)
-{
-        const unsigned char *ptr;
-        size_t len;
-        int ret = -1;
-
-        ptr = fido_assert_sig_ptr(assert, 0);
-        len = fido_assert_sig_len(assert, 0);
-        if (len != 64) {
-                skdebug(__func__, "bad length %zu", len);
-                goto out;
-        }
-        response->sig_r_len = len;
-        if ((response->sig_r = calloc(1, response->sig_r_len)) == NULL) {
-                skdebug(__func__, "calloc signature failed");
-                goto out;
-        }
-        memcpy(response->sig_r, ptr, len);
-        ret = 0;
- out:
-        if (ret != 0) {
-                free(response->sig_r);
-                response->sig_r = NULL;
-        }
-        return ret;
-}
-
-static int
-pack_sig(int alg, fido_assert_t *assert, struct sk_sign_response *response)
-{
-        switch(alg) {
-#ifdef WITH_OPENSSL
-        case SK_ECDSA:
-                return pack_sig_ecdsa(assert, response);
-#endif /* WITH_OPENSSL */
-        case SK_ED25519:
-                return pack_sig_ed25519(assert, response);
-        default:
-                return -1;
-        }
-}
-
-int
-sk_sign(int alg, const uint8_t *message, size_t message_len,
-    const char *application,
-    const uint8_t *key_handle, size_t key_handle_len,
-    uint8_t flags, struct sk_sign_response **sign_response)
-{
-        fido_assert_t *assert = NULL;
-        fido_dev_t *dev = NULL;
-        struct sk_sign_response *response = NULL;
-        int ret = -1;
-        int r;
-
-#ifdef SK_DEBUG
-        fido_init(FIDO_DEBUG);
-#endif
-
-        if (sign_response == NULL) {
-                skdebug(__func__, "sign_response == NULL");
-                goto out;
-        }
-        *sign_response = NULL;
-        if ((dev = find_device(application, key_handle,
-            key_handle_len)) == NULL) {
-                skdebug(__func__, "couldn't find device for key handle");
-                goto out;
-        }
-        if ((assert = fido_assert_new()) == NULL) {
-                skdebug(__func__, "fido_assert_new failed");
-                goto out;
-        }
-        if ((r = fido_assert_set_clientdata_hash(assert, message,
-            message_len)) != FIDO_OK) {
-                skdebug(__func__, "fido_assert_set_clientdata_hash: %s",
-                    fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_assert_set_rp(assert, application)) != FIDO_OK) {
-                skdebug(__func__, "fido_assert_set_rp: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_assert_allow_cred(assert, key_handle,
-            key_handle_len)) != FIDO_OK) {
-                skdebug(__func__, "fido_assert_allow_cred: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_assert_set_up(assert,
-            (flags & SK_USER_PRESENCE_REQD) ?
-            FIDO_OPT_TRUE : FIDO_OPT_FALSE)) != FIDO_OK) {
-                skdebug(__func__, "fido_assert_set_up: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((r = fido_dev_get_assert(dev, assert, NULL)) != FIDO_OK) {
-                skdebug(__func__, "fido_dev_get_assert: %s", fido_strerr(r));
-                goto out;
-        }
-        if ((response = calloc(1, sizeof(*response))) == NULL) {
-                skdebug(__func__, "calloc response failed");
-                goto out;
-        }
-        response->flags = fido_assert_flags(assert, 0);
-        response->counter = fido_assert_sigcount(assert, 0);
-        if (pack_sig(alg, assert, response) != 0) {
-                skdebug(__func__, "pack_sig failed");
-                goto out;
-        }
-        *sign_response = response;
-        response = NULL;
-        ret = 0;
- out:
-        if (response != NULL) {
-                free(response->sig_r);
-                free(response->sig_s);
-                free(response);
-        }
-        if (dev != NULL) {
-                fido_dev_close(dev);
-                fido_dev_free(&dev);
-        }
-        if (assert != NULL) {
-                fido_assert_free(&assert);
-        }
-        return ret;
-}