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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:35:18 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:35:18 +0000
commitb750101eb236130cf056c675997decbac904cc49 (patch)
treea5df1a06754bdd014cb975c051c83b01c9a97532 /src/shared/libfido2-util.c
parentInitial commit. (diff)
downloadsystemd-b750101eb236130cf056c675997decbac904cc49.tar.xz
systemd-b750101eb236130cf056c675997decbac904cc49.zip
Adding upstream version 252.22.upstream/252.22
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/shared/libfido2-util.c')
-rw-r--r--src/shared/libfido2-util.c1164
1 files changed, 1164 insertions, 0 deletions
diff --git a/src/shared/libfido2-util.c b/src/shared/libfido2-util.c
new file mode 100644
index 0000000..525849e
--- /dev/null
+++ b/src/shared/libfido2-util.c
@@ -0,0 +1,1164 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "libfido2-util.h"
+
+#if HAVE_LIBFIDO2
+#include "alloc-util.h"
+#include "ask-password-api.h"
+#include "dlfcn-util.h"
+#include "format-table.h"
+#include "glyph-util.h"
+#include "log.h"
+#include "memory-util.h"
+#include "random-util.h"
+#include "strv.h"
+#include "unistd.h"
+
+static void *libfido2_dl = NULL;
+
+int (*sym_fido_assert_allow_cred)(fido_assert_t *, const unsigned char *, size_t) = NULL;
+void (*sym_fido_assert_free)(fido_assert_t **) = NULL;
+size_t (*sym_fido_assert_hmac_secret_len)(const fido_assert_t *, size_t) = NULL;
+const unsigned char* (*sym_fido_assert_hmac_secret_ptr)(const fido_assert_t *, size_t) = NULL;
+fido_assert_t* (*sym_fido_assert_new)(void) = NULL;
+int (*sym_fido_assert_set_clientdata_hash)(fido_assert_t *, const unsigned char *, size_t) = NULL;
+int (*sym_fido_assert_set_extensions)(fido_assert_t *, int) = NULL;
+int (*sym_fido_assert_set_hmac_salt)(fido_assert_t *, const unsigned char *, size_t) = NULL;
+int (*sym_fido_assert_set_rp)(fido_assert_t *, const char *) = NULL;
+int (*sym_fido_assert_set_up)(fido_assert_t *, fido_opt_t) = NULL;
+int (*sym_fido_assert_set_uv)(fido_assert_t *, fido_opt_t) = NULL;
+size_t (*sym_fido_cbor_info_extensions_len)(const fido_cbor_info_t *) = NULL;
+char **(*sym_fido_cbor_info_extensions_ptr)(const fido_cbor_info_t *) = NULL;
+void (*sym_fido_cbor_info_free)(fido_cbor_info_t **) = NULL;
+fido_cbor_info_t* (*sym_fido_cbor_info_new)(void) = NULL;
+size_t (*sym_fido_cbor_info_options_len)(const fido_cbor_info_t *) = NULL;
+char** (*sym_fido_cbor_info_options_name_ptr)(const fido_cbor_info_t *) = NULL;
+const bool* (*sym_fido_cbor_info_options_value_ptr)(const fido_cbor_info_t *) = NULL;
+void (*sym_fido_cred_free)(fido_cred_t **) = NULL;
+size_t (*sym_fido_cred_id_len)(const fido_cred_t *) = NULL;
+const unsigned char* (*sym_fido_cred_id_ptr)(const fido_cred_t *) = NULL;
+fido_cred_t* (*sym_fido_cred_new)(void) = NULL;
+int (*sym_fido_cred_set_clientdata_hash)(fido_cred_t *, const unsigned char *, size_t) = NULL;
+int (*sym_fido_cred_set_extensions)(fido_cred_t *, int) = NULL;
+int (*sym_fido_cred_set_rk)(fido_cred_t *, fido_opt_t) = NULL;
+int (*sym_fido_cred_set_rp)(fido_cred_t *, const char *, const char *) = NULL;
+int (*sym_fido_cred_set_type)(fido_cred_t *, int) = NULL;
+int (*sym_fido_cred_set_user)(fido_cred_t *, const unsigned char *, size_t, const char *, const char *, const char *) = NULL;
+int (*sym_fido_cred_set_uv)(fido_cred_t *, fido_opt_t) = NULL;
+void (*sym_fido_dev_free)(fido_dev_t **) = NULL;
+int (*sym_fido_dev_get_assert)(fido_dev_t *, fido_assert_t *, const char *) = NULL;
+int (*sym_fido_dev_get_cbor_info)(fido_dev_t *, fido_cbor_info_t *) = NULL;
+void (*sym_fido_dev_info_free)(fido_dev_info_t **, size_t) = NULL;
+int (*sym_fido_dev_info_manifest)(fido_dev_info_t *, size_t, size_t *) = NULL;
+const char* (*sym_fido_dev_info_manufacturer_string)(const fido_dev_info_t *) = NULL;
+const char* (*sym_fido_dev_info_product_string)(const fido_dev_info_t *) = NULL;
+fido_dev_info_t* (*sym_fido_dev_info_new)(size_t) = NULL;
+const char* (*sym_fido_dev_info_path)(const fido_dev_info_t *) = NULL;
+const fido_dev_info_t* (*sym_fido_dev_info_ptr)(const fido_dev_info_t *, size_t) = NULL;
+bool (*sym_fido_dev_is_fido2)(const fido_dev_t *) = NULL;
+int (*sym_fido_dev_make_cred)(fido_dev_t *, fido_cred_t *, const char *) = NULL;
+fido_dev_t* (*sym_fido_dev_new)(void) = NULL;
+int (*sym_fido_dev_open)(fido_dev_t *, const char *) = NULL;
+int (*sym_fido_dev_close)(fido_dev_t *) = NULL;
+const char* (*sym_fido_strerr)(int) = NULL;
+
+int dlopen_libfido2(void) {
+ return dlopen_many_sym_or_warn(
+ &libfido2_dl, "libfido2.so.1", LOG_DEBUG,
+ DLSYM_ARG(fido_assert_allow_cred),
+ DLSYM_ARG(fido_assert_free),
+ DLSYM_ARG(fido_assert_hmac_secret_len),
+ DLSYM_ARG(fido_assert_hmac_secret_ptr),
+ DLSYM_ARG(fido_assert_new),
+ DLSYM_ARG(fido_assert_set_clientdata_hash),
+ DLSYM_ARG(fido_assert_set_extensions),
+ DLSYM_ARG(fido_assert_set_hmac_salt),
+ DLSYM_ARG(fido_assert_set_rp),
+ DLSYM_ARG(fido_assert_set_up),
+ DLSYM_ARG(fido_assert_set_uv),
+ DLSYM_ARG(fido_cbor_info_extensions_len),
+ DLSYM_ARG(fido_cbor_info_extensions_ptr),
+ DLSYM_ARG(fido_cbor_info_free),
+ DLSYM_ARG(fido_cbor_info_new),
+ DLSYM_ARG(fido_cbor_info_options_len),
+ DLSYM_ARG(fido_cbor_info_options_name_ptr),
+ DLSYM_ARG(fido_cbor_info_options_value_ptr),
+ DLSYM_ARG(fido_cred_free),
+ DLSYM_ARG(fido_cred_id_len),
+ DLSYM_ARG(fido_cred_id_ptr),
+ DLSYM_ARG(fido_cred_new),
+ DLSYM_ARG(fido_cred_set_clientdata_hash),
+ DLSYM_ARG(fido_cred_set_extensions),
+ DLSYM_ARG(fido_cred_set_rk),
+ DLSYM_ARG(fido_cred_set_rp),
+ DLSYM_ARG(fido_cred_set_type),
+ DLSYM_ARG(fido_cred_set_user),
+ DLSYM_ARG(fido_cred_set_uv),
+ DLSYM_ARG(fido_dev_free),
+ DLSYM_ARG(fido_dev_get_assert),
+ DLSYM_ARG(fido_dev_get_cbor_info),
+ DLSYM_ARG(fido_dev_info_free),
+ DLSYM_ARG(fido_dev_info_manifest),
+ DLSYM_ARG(fido_dev_info_manufacturer_string),
+ DLSYM_ARG(fido_dev_info_new),
+ DLSYM_ARG(fido_dev_info_path),
+ DLSYM_ARG(fido_dev_info_product_string),
+ DLSYM_ARG(fido_dev_info_ptr),
+ DLSYM_ARG(fido_dev_is_fido2),
+ DLSYM_ARG(fido_dev_make_cred),
+ DLSYM_ARG(fido_dev_new),
+ DLSYM_ARG(fido_dev_open),
+ DLSYM_ARG(fido_dev_close),
+ DLSYM_ARG(fido_strerr));
+}
+
+static int verify_features(
+ fido_dev_t *d,
+ const char *path,
+ int log_level, /* the log level to use when device is not FIDO2 with hmac-secret */
+ bool *ret_has_rk,
+ bool *ret_has_client_pin,
+ bool *ret_has_up,
+ bool *ret_has_uv) {
+
+ _cleanup_(fido_cbor_info_free_wrapper) fido_cbor_info_t *di = NULL;
+ bool found_extension = false;
+ char **e, **o;
+ const bool *b;
+ bool has_rk = false, has_client_pin = false, has_up = true, has_uv = false; /* Defaults are per table in 5.4 in FIDO2 spec */
+ size_t n;
+ int r;
+
+ assert(d);
+ assert(path);
+
+ if (!sym_fido_dev_is_fido2(d))
+ return log_full_errno(log_level, SYNTHETIC_ERRNO(ENODEV),
+ "Specified device %s is not a FIDO2 device.", path);
+
+ di = sym_fido_cbor_info_new();
+ if (!di)
+ return log_oom();
+
+ r = sym_fido_dev_get_cbor_info(d, di);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to get CBOR device info for %s: %s", path, sym_fido_strerr(r));
+
+ e = sym_fido_cbor_info_extensions_ptr(di);
+ n = sym_fido_cbor_info_extensions_len(di);
+ for (size_t i = 0; i < n; i++) {
+ log_debug("FIDO2 device implements extension: %s", e[i]);
+ if (streq(e[i], "hmac-secret"))
+ found_extension = true;
+ }
+
+ o = sym_fido_cbor_info_options_name_ptr(di);
+ b = sym_fido_cbor_info_options_value_ptr(di);
+ n = sym_fido_cbor_info_options_len(di);
+ for (size_t i = 0; i < n; i++) {
+ log_debug("FIDO2 device implements option %s: %s", o[i], yes_no(b[i]));
+ if (streq(o[i], "rk"))
+ has_rk = b[i];
+ if (streq(o[i], "clientPin"))
+ has_client_pin = b[i];
+ if (streq(o[i], "up"))
+ has_up = b[i];
+ if (streq(o[i], "uv"))
+ has_uv = b[i];
+ }
+
+ if (!found_extension)
+ return log_full_errno(log_level,
+ SYNTHETIC_ERRNO(ENODEV),
+ "Specified device %s is a FIDO2 device, but does not support the required HMAC-SECRET extension.", path);
+
+ log_debug("Has rk ('Resident Key') support: %s\n"
+ "Has clientPin support: %s\n"
+ "Has up ('User Presence') support: %s\n"
+ "Has uv ('User Verification') support: %s\n",
+ yes_no(has_rk),
+ yes_no(has_client_pin),
+ yes_no(has_up),
+ yes_no(has_uv));
+
+ if (ret_has_rk)
+ *ret_has_rk = has_rk;
+ if (ret_has_client_pin)
+ *ret_has_client_pin = has_client_pin;
+ if (ret_has_up)
+ *ret_has_up = has_up;
+ if (ret_has_uv)
+ *ret_has_uv = has_uv;
+
+ return 0;
+}
+
+static int fido2_use_hmac_hash_specific_token(
+ const char *path,
+ const char *rp_id,
+ const void *salt,
+ size_t salt_size,
+ const void *cid,
+ size_t cid_size,
+ char **pins,
+ Fido2EnrollFlags required, /* client pin/user presence required */
+ void **ret_hmac,
+ size_t *ret_hmac_size) {
+
+ _cleanup_(fido_assert_free_wrapper) fido_assert_t *a = NULL;
+ _cleanup_(fido_dev_free_wrapper) fido_dev_t *d = NULL;
+ _cleanup_(erase_and_freep) void *hmac_copy = NULL;
+ bool has_up, has_client_pin, has_uv;
+ size_t hmac_size;
+ const void *hmac;
+ int r;
+
+ assert(path);
+ assert(rp_id);
+ assert(salt);
+ assert(cid);
+ assert(ret_hmac);
+ assert(ret_hmac_size);
+
+ d = sym_fido_dev_new();
+ if (!d)
+ return log_oom();
+
+ r = sym_fido_dev_open(d, path);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to open FIDO2 device %s: %s", path, sym_fido_strerr(r));
+
+ r = verify_features(d, path, LOG_ERR, NULL, &has_client_pin, &has_up, &has_uv);
+ if (r < 0)
+ return r;
+
+ if (!has_client_pin && FLAGS_SET(required, FIDO2ENROLL_PIN))
+ return log_error_errno(SYNTHETIC_ERRNO(EHWPOISON),
+ "PIN required to unlock, but FIDO2 device %s does not support it.",
+ path);
+
+ if (!has_up && FLAGS_SET(required, FIDO2ENROLL_UP))
+ return log_error_errno(SYNTHETIC_ERRNO(EHWPOISON),
+ "User presence test required to unlock, but FIDO2 device %s does not support it.",
+ path);
+
+ if (!has_uv && FLAGS_SET(required, FIDO2ENROLL_UV))
+ return log_error_errno(SYNTHETIC_ERRNO(EHWPOISON),
+ "User verification required to unlock, but FIDO2 device %s does not support it.",
+ path);
+
+ a = sym_fido_assert_new();
+ if (!a)
+ return log_oom();
+
+ r = sym_fido_assert_set_extensions(a, FIDO_EXT_HMAC_SECRET);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to enable HMAC-SECRET extension on FIDO2 assertion: %s", sym_fido_strerr(r));
+
+ r = sym_fido_assert_set_hmac_salt(a, salt, salt_size);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set salt on FIDO2 assertion: %s", sym_fido_strerr(r));
+
+ r = sym_fido_assert_set_rp(a, rp_id);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set FIDO2 assertion ID: %s", sym_fido_strerr(r));
+
+ r = sym_fido_assert_set_clientdata_hash(a, (const unsigned char[32]) {}, 32);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set FIDO2 assertion client data hash: %s", sym_fido_strerr(r));
+
+ r = sym_fido_assert_allow_cred(a, cid, cid_size);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to add FIDO2 assertion credential ID: %s", sym_fido_strerr(r));
+
+ log_info("Asking FIDO2 token for authentication.");
+
+ if (has_up) {
+ r = sym_fido_assert_set_up(a, FLAGS_SET(required, FIDO2ENROLL_UP) ? FIDO_OPT_TRUE : FIDO_OPT_FALSE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to %s FIDO2 user presence test: %s",
+ enable_disable(FLAGS_SET(required, FIDO2ENROLL_UP)),
+ sym_fido_strerr(r));
+
+ if (FLAGS_SET(required, FIDO2ENROLL_UP))
+ log_notice("%s%sPlease confirm presence on security token to unlock.",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "");
+ }
+
+ if (has_uv && !FLAGS_SET(required, FIDO2ENROLL_UV_OMIT)) {
+ r = sym_fido_assert_set_uv(a, FLAGS_SET(required, FIDO2ENROLL_UV) ? FIDO_OPT_TRUE : FIDO_OPT_FALSE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to %s FIDO2 user verification: %s",
+ enable_disable(FLAGS_SET(required, FIDO2ENROLL_UV)),
+ sym_fido_strerr(r));
+
+ if (FLAGS_SET(required, FIDO2ENROLL_UV))
+ log_notice("%s%sPlease verify user on security token to unlock.",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "");
+ }
+
+ for (;;) {
+ bool retry_with_up = false, retry_with_pin = false;
+
+ if (FLAGS_SET(required, FIDO2ENROLL_PIN)) {
+ /* OK, we need a pin, try with all pins in turn */
+ if (strv_isempty(pins))
+ r = FIDO_ERR_PIN_REQUIRED;
+ else
+ STRV_FOREACH(i, pins) {
+ r = sym_fido_dev_get_assert(d, a, *i);
+ if (r != FIDO_ERR_PIN_INVALID)
+ break;
+ }
+
+ } else
+ r = sym_fido_dev_get_assert(d, a, NULL);
+
+ /* In some conditions, where a PIN or UP is required we might accept that. Let's check the
+ * conditions and if so try immediately again. */
+
+ switch (r) {
+
+ case FIDO_ERR_UP_REQUIRED:
+ /* So the token asked for "up". Try to turn it on, for compat with systemd 248 and try again. */
+
+ if (!has_up)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for user presence test but doesn't advertise 'up' feature.");
+
+ if (FLAGS_SET(required, FIDO2ENROLL_UP))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for user presence test but was already enabled.");
+
+ if (FLAGS_SET(required, FIDO2ENROLL_UP_IF_NEEDED)) {
+ log_notice("%s%sPlease confirm presence on security to unlock.",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "");
+ retry_with_up = true;
+ }
+
+ break;
+
+ case FIDO_ERR_UNSUPPORTED_OPTION:
+ /* AuthenTrend ATKey.Pro returns this instead of FIDO_ERR_UP_REQUIRED, let's handle
+ * it gracefully (also see below.) */
+
+ if (has_up && (required & (FIDO2ENROLL_UP|FIDO2ENROLL_UP_IF_NEEDED)) == FIDO2ENROLL_UP_IF_NEEDED) {
+ log_notice("%s%sGot unsupported option error when when user presence test is turned off. Trying with user presence test turned on.",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "");
+ retry_with_up = true;
+ }
+
+ break;
+
+ case FIDO_ERR_PIN_REQUIRED:
+ /* A pin was requested. Maybe supply one, if we are configured to do so on request */
+
+ if (!has_client_pin)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for PIN but doesn't advertise 'clientPin' feature.");
+
+ if (FLAGS_SET(required, FIDO2ENROLL_PIN) && !strv_isempty(pins))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for PIN but one was already supplied.");
+
+ if ((required & (FIDO2ENROLL_PIN|FIDO2ENROLL_PIN_IF_NEEDED)) == FIDO2ENROLL_PIN_IF_NEEDED) {
+ /* If a PIN so far wasn't specified but is requested by the device, and
+ * FIDO2ENROLL_PIN_IF_NEEDED is set, then provide it */
+ log_debug("Retrying to create credential with PIN.");
+ retry_with_pin = true;
+ }
+
+ break;
+
+ default:
+ break;
+ }
+
+ if (!retry_with_up && !retry_with_pin)
+ break;
+
+ if (retry_with_up) {
+ r = sym_fido_assert_set_up(a, FIDO_OPT_TRUE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to enable FIDO2 user presence test: %s", sym_fido_strerr(r));
+
+ required |= FIDO2ENROLL_UP;
+ }
+
+ if (retry_with_pin)
+ required |= FIDO2ENROLL_PIN;
+ }
+
+ switch (r) {
+ case FIDO_OK:
+ break;
+ case FIDO_ERR_NO_CREDENTIALS:
+ return log_error_errno(SYNTHETIC_ERRNO(EBADSLT),
+ "Wrong security token; needed credentials not present on token.");
+ case FIDO_ERR_PIN_REQUIRED:
+ return log_error_errno(SYNTHETIC_ERRNO(ENOANO),
+ "Security token requires PIN.");
+ case FIDO_ERR_PIN_AUTH_BLOCKED:
+ return log_error_errno(SYNTHETIC_ERRNO(EOWNERDEAD),
+ "PIN of security token is blocked, please remove/reinsert token.");
+#ifdef FIDO_ERR_UV_BLOCKED
+ case FIDO_ERR_UV_BLOCKED:
+ return log_error_errno(SYNTHETIC_ERRNO(EOWNERDEAD),
+ "Verification of security token is blocked, please remove/reinsert token.");
+#endif
+ case FIDO_ERR_PIN_INVALID:
+ return log_error_errno(SYNTHETIC_ERRNO(ENOLCK),
+ "PIN of security token incorrect.");
+ case FIDO_ERR_UP_REQUIRED:
+ return log_error_errno(SYNTHETIC_ERRNO(EMEDIUMTYPE),
+ "User presence required.");
+ case FIDO_ERR_ACTION_TIMEOUT:
+ return log_error_errno(SYNTHETIC_ERRNO(ENOSTR),
+ "Token action timeout. (User didn't interact with token quickly enough.)");
+ default:
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to ask token for assertion: %s", sym_fido_strerr(r));
+ }
+
+ hmac = sym_fido_assert_hmac_secret_ptr(a, 0);
+ if (!hmac)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to retrieve HMAC secret.");
+
+ hmac_size = sym_fido_assert_hmac_secret_len(a, 0);
+
+ hmac_copy = memdup(hmac, hmac_size);
+ if (!hmac_copy)
+ return log_oom();
+
+ *ret_hmac = TAKE_PTR(hmac_copy);
+ *ret_hmac_size = hmac_size;
+ return 0;
+}
+
+/* COSE_ECDH_ES256 is not usable with fido_cred_set_type() thus it's not listed here. */
+static const char *fido2_algorithm_to_string(int alg) {
+ switch(alg) {
+ case COSE_ES256:
+ return "es256";
+ case COSE_RS256:
+ return "rs256";
+ case COSE_EDDSA:
+ return "eddsa";
+ default:
+ return NULL;
+ }
+}
+
+int fido2_use_hmac_hash(
+ const char *device,
+ const char *rp_id,
+ const void *salt,
+ size_t salt_size,
+ const void *cid,
+ size_t cid_size,
+ char **pins,
+ Fido2EnrollFlags required, /* client pin/user presence required */
+ void **ret_hmac,
+ size_t *ret_hmac_size) {
+
+ size_t allocated = 64, found = 0;
+ fido_dev_info_t *di = NULL;
+ int r;
+
+ r = dlopen_libfido2();
+ if (r < 0)
+ return log_error_errno(r, "FIDO2 support is not installed.");
+
+ if (device)
+ return fido2_use_hmac_hash_specific_token(device, rp_id, salt, salt_size, cid, cid_size, pins, required, ret_hmac, ret_hmac_size);
+
+ di = sym_fido_dev_info_new(allocated);
+ if (!di)
+ return log_oom();
+
+ r = sym_fido_dev_info_manifest(di, allocated, &found);
+ if (r == FIDO_ERR_INTERNAL) {
+ /* The library returns FIDO_ERR_INTERNAL when no devices are found. I wish it wouldn't. */
+ r = log_debug_errno(SYNTHETIC_ERRNO(EAGAIN), "Got FIDO_ERR_INTERNAL, assuming no devices.");
+ goto finish;
+ }
+ if (r != FIDO_OK) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to enumerate FIDO2 devices: %s", sym_fido_strerr(r));
+ goto finish;
+ }
+
+ for (size_t i = 0; i < found; i++) {
+ const fido_dev_info_t *entry;
+ const char *path;
+
+ entry = sym_fido_dev_info_ptr(di, i);
+ if (!entry) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to get device information for FIDO device %zu.", i);
+ goto finish;
+ }
+
+ path = sym_fido_dev_info_path(entry);
+ if (!path) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to query FIDO device path.");
+ goto finish;
+ }
+
+ r = fido2_use_hmac_hash_specific_token(path, rp_id, salt, salt_size, cid, cid_size, pins, required, ret_hmac, ret_hmac_size);
+ if (!IN_SET(r,
+ -EBADSLT, /* device doesn't understand our credential hash */
+ -ENODEV /* device is not a FIDO2 device with HMAC-SECRET */))
+ goto finish;
+ }
+
+ r = -EAGAIN;
+
+finish:
+ sym_fido_dev_info_free(&di, allocated);
+ return r;
+}
+
+#define FIDO2_SALT_SIZE 32
+
+int fido2_generate_hmac_hash(
+ const char *device,
+ const char *rp_id,
+ const char *rp_name,
+ const void *user_id, size_t user_id_len,
+ const char *user_name,
+ const char *user_display_name,
+ const char *user_icon,
+ const char *askpw_icon_name,
+ Fido2EnrollFlags lock_with,
+ int cred_alg,
+ void **ret_cid, size_t *ret_cid_size,
+ void **ret_salt, size_t *ret_salt_size,
+ void **ret_secret, size_t *ret_secret_size,
+ char **ret_usedpin,
+ Fido2EnrollFlags *ret_locked_with) {
+
+ _cleanup_(erase_and_freep) void *salt = NULL, *secret_copy = NULL;
+ _cleanup_(fido_assert_free_wrapper) fido_assert_t *a = NULL;
+ _cleanup_(fido_cred_free_wrapper) fido_cred_t *c = NULL;
+ _cleanup_(fido_dev_free_wrapper) fido_dev_t *d = NULL;
+ _cleanup_(erase_and_freep) char *used_pin = NULL;
+ bool has_rk, has_client_pin, has_up, has_uv;
+ _cleanup_free_ char *cid_copy = NULL;
+ size_t cid_size, secret_size;
+ const void *cid, *secret;
+ int r;
+
+ assert(device);
+ assert(ret_cid);
+ assert(ret_cid_size);
+ assert(ret_salt);
+ assert(ret_salt_size);
+ assert(ret_secret);
+ assert(ret_secret_size);
+
+ /* Construction is like this: we generate a salt of 32 bytes. We then ask the FIDO2 device to
+ * HMAC-SHA256 it for us with its internal key. The result is the key used by LUKS and account
+ * authentication. LUKS and UNIX password auth all do their own salting before hashing, so that FIDO2
+ * device never sees the volume key.
+ *
+ * S = HMAC-SHA256(I, D)
+ *
+ * with: S → LUKS/account authentication key (never stored)
+ * I → internal key on FIDO2 device (stored in the FIDO2 device)
+ * D → salt we generate here (stored in the privileged part of the JSON record)
+ *
+ */
+
+ assert(device);
+ assert((lock_with & ~(FIDO2ENROLL_PIN|FIDO2ENROLL_UP|FIDO2ENROLL_UV)) == 0);
+
+ r = dlopen_libfido2();
+ if (r < 0)
+ return log_error_errno(r, "FIDO2 token support is not installed.");
+
+ salt = malloc(FIDO2_SALT_SIZE);
+ if (!salt)
+ return log_oom();
+
+ r = crypto_random_bytes(salt, FIDO2_SALT_SIZE);
+ if (r < 0)
+ return log_error_errno(r, "Failed to generate salt: %m");
+
+ d = sym_fido_dev_new();
+ if (!d)
+ return log_oom();
+
+ r = sym_fido_dev_open(d, device);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to open FIDO2 device %s: %s", device, sym_fido_strerr(r));
+
+ r = verify_features(d, device, LOG_ERR, &has_rk, &has_client_pin, &has_up, &has_uv);
+ if (r < 0)
+ return r;
+
+ /* While enrolling degrade gracefully if the requested feature set isn't available, but let the user know */
+ if (!has_client_pin && FLAGS_SET(lock_with, FIDO2ENROLL_PIN)) {
+ log_notice("Requested to lock with PIN, but FIDO2 device %s does not support it, disabling.", device);
+ lock_with &= ~FIDO2ENROLL_PIN;
+ }
+
+ if (!has_up && FLAGS_SET(lock_with, FIDO2ENROLL_UP)) {
+ log_notice("Locking with user presence test requested, but FIDO2 device %s does not support it, disabling.", device);
+ lock_with &= ~FIDO2ENROLL_UP;
+ }
+
+ if (!has_uv && FLAGS_SET(lock_with, FIDO2ENROLL_UV)) {
+ log_notice("Locking with user verification test requested, but FIDO2 device %s does not support it, disabling.", device);
+ lock_with &= ~FIDO2ENROLL_UV;
+ }
+
+ c = sym_fido_cred_new();
+ if (!c)
+ return log_oom();
+
+ r = sym_fido_cred_set_extensions(c, FIDO_EXT_HMAC_SECRET);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to enable HMAC-SECRET extension on FIDO2 credential: %s", sym_fido_strerr(r));
+
+ r = sym_fido_cred_set_rp(c, rp_id, rp_name);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set FIDO2 credential relying party ID/name: %s", sym_fido_strerr(r));
+
+ r = sym_fido_cred_set_type(c, cred_alg);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set FIDO2 credential type to %s: %s", fido2_algorithm_to_string(cred_alg), sym_fido_strerr(r));
+
+ r = sym_fido_cred_set_user(
+ c,
+ user_id, user_id_len,
+ user_name,
+ user_display_name,
+ user_icon);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set FIDO2 credential user data: %s", sym_fido_strerr(r));
+
+ r = sym_fido_cred_set_clientdata_hash(c, (const unsigned char[32]) {}, 32);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set FIDO2 client data hash: %s", sym_fido_strerr(r));
+
+ if (has_rk) {
+ r = sym_fido_cred_set_rk(c, FIDO_OPT_FALSE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to turn off FIDO2 resident key option of credential: %s", sym_fido_strerr(r));
+ }
+
+ if (has_uv) {
+ r = sym_fido_cred_set_uv(c, FIDO_OPT_FALSE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to turn off FIDO2 user verification option of credential: %s", sym_fido_strerr(r));
+ }
+
+ /* As per specification "up" is assumed to be implicit when making credentials, hence we don't
+ * explicitly enable/disable it here */
+
+ log_info("Initializing FIDO2 credential on security token.");
+
+ if (has_uv || has_up)
+ log_notice("%s%s(Hint: This might require confirmation of user presence on security token.)",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "");
+
+ r = sym_fido_dev_make_cred(d, c, NULL);
+ if (r == FIDO_ERR_PIN_REQUIRED) {
+
+ if (!has_client_pin)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for PIN but doesn't advertise 'clientPin' feature.");
+
+ for (;;) {
+ _cleanup_(strv_free_erasep) char **pin = NULL;
+
+ r = ask_password_auto("Please enter security token PIN:", askpw_icon_name, NULL, "fido2-pin", "fido2-pin", USEC_INFINITY, 0, &pin);
+ if (r < 0)
+ return log_error_errno(r, "Failed to acquire user PIN: %m");
+
+ r = FIDO_ERR_PIN_INVALID;
+ STRV_FOREACH(i, pin) {
+ if (isempty(*i)) {
+ log_notice("PIN may not be empty.");
+ continue;
+ }
+
+ r = sym_fido_dev_make_cred(d, c, *i);
+ if (r == FIDO_OK) {
+ used_pin = strdup(*i);
+ if (!used_pin)
+ return log_oom();
+ break;
+ }
+ if (r != FIDO_ERR_PIN_INVALID)
+ break;
+ }
+
+ if (r != FIDO_ERR_PIN_INVALID)
+ break;
+
+ log_notice("PIN incorrect, please try again.");
+ }
+ }
+ if (r == FIDO_ERR_PIN_AUTH_BLOCKED)
+ return log_notice_errno(SYNTHETIC_ERRNO(EPERM),
+ "Token PIN is currently blocked, please remove and reinsert token.");
+#ifdef FIDO_ERR_UV_BLOCKED
+ if (r == FIDO_ERR_UV_BLOCKED)
+ return log_notice_errno(SYNTHETIC_ERRNO(EPERM),
+ "Token verification is currently blocked, please remove and reinsert token.");
+#endif
+ if (r == FIDO_ERR_ACTION_TIMEOUT)
+ return log_error_errno(SYNTHETIC_ERRNO(ENOSTR),
+ "Token action timeout. (User didn't interact with token quickly enough.)");
+ if (r == FIDO_ERR_UNSUPPORTED_ALGORITHM)
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "Token doesn't support credential algorithm %s.", fido2_algorithm_to_string(cred_alg));
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to generate FIDO2 credential: %s", sym_fido_strerr(r));
+
+ cid = sym_fido_cred_id_ptr(c);
+ if (!cid)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to get FIDO2 credential ID.");
+
+ cid_size = sym_fido_cred_id_len(c);
+
+ a = sym_fido_assert_new();
+ if (!a)
+ return log_oom();
+
+ r = sym_fido_assert_set_extensions(a, FIDO_EXT_HMAC_SECRET);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to enable HMAC-SECRET extension on FIDO2 assertion: %s", sym_fido_strerr(r));
+
+ r = sym_fido_assert_set_hmac_salt(a, salt, FIDO2_SALT_SIZE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set salt on FIDO2 assertion: %s", sym_fido_strerr(r));
+
+ r = sym_fido_assert_set_rp(a, rp_id);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set FIDO2 assertion ID: %s", sym_fido_strerr(r));
+
+ r = sym_fido_assert_set_clientdata_hash(a, (const unsigned char[32]) {}, 32);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to set FIDO2 assertion client data hash: %s", sym_fido_strerr(r));
+
+ r = sym_fido_assert_allow_cred(a, cid, cid_size);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to add FIDO2 assertion credential ID: %s", sym_fido_strerr(r));
+
+ log_info("Generating secret key on FIDO2 security token.");
+
+ if (has_up) {
+ r = sym_fido_assert_set_up(a, FLAGS_SET(lock_with, FIDO2ENROLL_UP) ? FIDO_OPT_TRUE : FIDO_OPT_FALSE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to %s FIDO2 user presence test: %s",
+ enable_disable(FLAGS_SET(lock_with, FIDO2ENROLL_UP)),
+ sym_fido_strerr(r));
+
+ if (FLAGS_SET(lock_with, FIDO2ENROLL_UP))
+ log_notice("%s%sIn order to allow secret key generation, please confirm presence on security token.",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "");
+ }
+
+ if (has_uv) {
+ r = sym_fido_assert_set_uv(a, FLAGS_SET(lock_with, FIDO2ENROLL_UV) ? FIDO_OPT_TRUE : FIDO_OPT_FALSE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to %s FIDO user verification: %s",
+ enable_disable(FLAGS_SET(lock_with, FIDO2ENROLL_UV)),
+ sym_fido_strerr(r));
+
+ if (FLAGS_SET(lock_with, FIDO2ENROLL_UV))
+ log_notice("%s%sIn order to allow secret key generation, please verify user on security token.",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "");
+ }
+
+ for (;;) {
+ bool retry_with_up = false, retry_with_pin = false;
+
+ r = sym_fido_dev_get_assert(d, a, FLAGS_SET(lock_with, FIDO2ENROLL_PIN) ? used_pin : NULL);
+
+ switch (r) {
+
+ case FIDO_ERR_UP_REQUIRED:
+ /* If the token asks for "up" when we turn off, then this might be a feature that
+ * isn't optional. Let's enable it */
+
+ if (!has_up)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for user presence test but doesn't advertise 'up' feature.");
+
+ if (FLAGS_SET(lock_with, FIDO2ENROLL_UP))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for user presence test but was already enabled.");
+
+ log_notice("%s%sLocking without user presence test requested, but FIDO2 device %s requires it, enabling.",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "",
+ device);
+
+ retry_with_up = true;
+ break;
+
+ case FIDO_ERR_UNSUPPORTED_OPTION:
+ /* AuthenTrend ATKey.Pro says it supports "up", but if we disable it it will fail
+ * with FIDO_ERR_UNSUPPORTED_OPTION, probably because it isn't actually
+ * optional. Let's see if turning it on works. This is very similar to the
+ * FIDO_ERR_UP_REQUIRED case, but since the error is so vague we implement it
+ * slightly more defensively. */
+
+ if (has_up && !FLAGS_SET(lock_with, FIDO2ENROLL_UP)) {
+ log_notice("%s%sGot unsupported option error when when user presence test is turned off. Trying with user presence test turned on.",
+ emoji_enabled() ? special_glyph(SPECIAL_GLYPH_TOUCH) : "",
+ emoji_enabled() ? " " : "");
+ retry_with_up = true;
+ }
+
+ break;
+
+ case FIDO_ERR_PIN_REQUIRED:
+ if (!has_client_pin)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for client PIN check but doesn't advertise 'clientPin' feature.");
+
+ if (FLAGS_SET(lock_with, FIDO2ENROLL_PIN))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Token asks for user client PIN check but was already enabled.");
+
+ log_debug("Token requires PIN for assertion, enabling.");
+ retry_with_pin = true;
+ break;
+
+ default:
+ break;
+ }
+
+ if (!retry_with_up && !retry_with_pin)
+ break;
+
+ if (retry_with_up) {
+ r = sym_fido_assert_set_up(a, FIDO_OPT_TRUE);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to enable FIDO2 user presence test: %s", sym_fido_strerr(r));
+
+ lock_with |= FIDO2ENROLL_UP;
+ }
+
+ if (retry_with_pin)
+ lock_with |= FIDO2ENROLL_PIN;
+ }
+
+ if (r == FIDO_ERR_ACTION_TIMEOUT)
+ return log_error_errno(SYNTHETIC_ERRNO(ENOSTR),
+ "Token action timeout. (User didn't interact with token quickly enough.)");
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to ask token for assertion: %s", sym_fido_strerr(r));
+
+ secret = sym_fido_assert_hmac_secret_ptr(a, 0);
+ if (!secret)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to retrieve HMAC secret.");
+
+ secret_size = sym_fido_assert_hmac_secret_len(a, 0);
+
+ secret_copy = memdup(secret, secret_size);
+ if (!secret_copy)
+ return log_oom();
+
+ cid_copy = memdup(cid, cid_size);
+ if (!cid_copy)
+ return log_oom();
+
+ *ret_cid = TAKE_PTR(cid_copy);
+ *ret_cid_size = cid_size;
+ *ret_salt = TAKE_PTR(salt);
+ *ret_salt_size = FIDO2_SALT_SIZE;
+ *ret_secret = TAKE_PTR(secret_copy);
+ *ret_secret_size = secret_size;
+
+ if (ret_usedpin)
+ *ret_usedpin = TAKE_PTR(used_pin);
+
+ if (ret_locked_with)
+ *ret_locked_with = lock_with;
+
+ return 0;
+}
+#endif
+
+#if HAVE_LIBFIDO2
+static int check_device_is_fido2_with_hmac_secret(const char *path) {
+ _cleanup_(fido_dev_free_wrapper) fido_dev_t *d = NULL;
+ int r;
+
+ d = sym_fido_dev_new();
+ if (!d)
+ return log_oom();
+
+ r = sym_fido_dev_open(d, path);
+ if (r != FIDO_OK)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to open FIDO2 device %s: %s", path, sym_fido_strerr(r));
+
+ r = verify_features(d, path, LOG_DEBUG, NULL, NULL, NULL, NULL);
+ if (r == -ENODEV) /* Not a FIDO2 device, or not implementing 'hmac-secret' */
+ return false;
+ if (r < 0)
+ return r;
+
+ return true;
+}
+#endif
+
+int fido2_list_devices(void) {
+#if HAVE_LIBFIDO2
+ _cleanup_(table_unrefp) Table *t = NULL;
+ size_t allocated = 64, found = 0;
+ fido_dev_info_t *di = NULL;
+ int r;
+
+ r = dlopen_libfido2();
+ if (r < 0)
+ return log_error_errno(r, "FIDO2 token support is not installed.");
+
+ di = sym_fido_dev_info_new(allocated);
+ if (!di)
+ return log_oom();
+
+ r = sym_fido_dev_info_manifest(di, allocated, &found);
+ if (r == FIDO_ERR_INTERNAL || (r == FIDO_OK && found == 0)) {
+ /* The library returns FIDO_ERR_INTERNAL when no devices are found. I wish it wouldn't. */
+ log_info("No FIDO2 devices found.");
+ r = 0;
+ goto finish;
+ }
+ if (r != FIDO_OK) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to enumerate FIDO2 devices: %s", sym_fido_strerr(r));
+ goto finish;
+ }
+
+ t = table_new("path", "manufacturer", "product");
+ if (!t) {
+ r = log_oom();
+ goto finish;
+ }
+
+ for (size_t i = 0; i < found; i++) {
+ const fido_dev_info_t *entry;
+
+ entry = sym_fido_dev_info_ptr(di, i);
+ if (!entry) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to get device information for FIDO device %zu.", i);
+ goto finish;
+ }
+
+ r = check_device_is_fido2_with_hmac_secret(sym_fido_dev_info_path(entry));
+ if (r < 0)
+ goto finish;
+ if (!r)
+ continue;
+
+ r = table_add_many(
+ t,
+ TABLE_PATH, sym_fido_dev_info_path(entry),
+ TABLE_STRING, sym_fido_dev_info_manufacturer_string(entry),
+ TABLE_STRING, sym_fido_dev_info_product_string(entry));
+ if (r < 0) {
+ table_log_add_error(r);
+ goto finish;
+ }
+ }
+
+ r = table_print(t, stdout);
+ if (r < 0) {
+ log_error_errno(r, "Failed to show device table: %m");
+ goto finish;
+ }
+
+ r = 0;
+
+finish:
+ sym_fido_dev_info_free(&di, allocated);
+ return r;
+#else
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "FIDO2 tokens not supported on this build.");
+#endif
+}
+
+int fido2_find_device_auto(char **ret) {
+#if HAVE_LIBFIDO2
+ _cleanup_free_ char *copy = NULL;
+ size_t di_size = 64, found = 0;
+ const fido_dev_info_t *entry;
+ fido_dev_info_t *di = NULL;
+ const char *path;
+ int r;
+
+ r = dlopen_libfido2();
+ if (r < 0)
+ return log_error_errno(r, "FIDO2 token support is not installed.");
+
+ di = sym_fido_dev_info_new(di_size);
+ if (!di)
+ return log_oom();
+
+ r = sym_fido_dev_info_manifest(di, di_size, &found);
+ if (r == FIDO_ERR_INTERNAL || (r == FIDO_OK && found == 0)) {
+ /* The library returns FIDO_ERR_INTERNAL when no devices are found. I wish it wouldn't. */
+ r = log_error_errno(SYNTHETIC_ERRNO(ENODEV), "No FIDO devices found.");
+ goto finish;
+ }
+ if (r != FIDO_OK) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to enumerate FIDO devices: %s", sym_fido_strerr(r));
+ goto finish;
+ }
+ if (found > 1) {
+ r = log_error_errno(SYNTHETIC_ERRNO(ENOTUNIQ), "More than one FIDO device found.");
+ goto finish;
+ }
+
+ entry = sym_fido_dev_info_ptr(di, 0);
+ if (!entry) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to get device information for FIDO device 0.");
+ goto finish;
+ }
+
+ r = check_device_is_fido2_with_hmac_secret(sym_fido_dev_info_path(entry));
+ if (r < 0)
+ goto finish;
+ if (!r) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "FIDO device discovered does not implement FIDO2 with 'hmac-secret' extension.");
+ goto finish;
+ }
+
+ path = sym_fido_dev_info_path(entry);
+ if (!path) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Failed to query FIDO device path.");
+ goto finish;
+ }
+
+ copy = strdup(path);
+ if (!copy) {
+ r = log_oom();
+ goto finish;
+ }
+
+ *ret = TAKE_PTR(copy);
+ r = 0;
+
+finish:
+ sym_fido_dev_info_free(&di, di_size);
+ return r;
+#else
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "FIDO2 tokens not supported on this build.");
+#endif
+}
+
+int fido2_have_device(const char *device) {
+#if HAVE_LIBFIDO2
+ size_t allocated = 64, found = 0;
+ fido_dev_info_t *di = NULL;
+ int r;
+
+ /* Return == 0 if not devices are found, > 0 if at least one is found */
+
+ r = dlopen_libfido2();
+ if (r < 0)
+ return log_error_errno(r, "FIDO2 support is not installed.");
+
+ if (device) {
+ if (access(device, F_OK) < 0) {
+ if (errno == ENOENT)
+ return 0;
+
+ return log_error_errno(errno, "Failed to determine whether device '%s' exists: %m", device);
+ }
+
+ return 1;
+ }
+
+ di = sym_fido_dev_info_new(allocated);
+ if (!di)
+ return log_oom();
+
+ r = sym_fido_dev_info_manifest(di, allocated, &found);
+ if (r == FIDO_ERR_INTERNAL) {
+ /* The library returns FIDO_ERR_INTERNAL when no devices are found. I wish it wouldn't. */
+ r = 0;
+ goto finish;
+ }
+ if (r != FIDO_OK) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EIO), "Failed to enumerate FIDO2 devices: %s", sym_fido_strerr(r));
+ goto finish;
+ }
+
+ r = found;
+
+finish:
+ sym_fido_dev_info_free(&di, allocated);
+ return r;
+#else
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "FIDO2 tokens not supported on this build.");
+#endif
+}
+
+#if HAVE_LIBFIDO2
+int parse_fido2_algorithm(const char *s, int *ret) {
+ int a;
+
+ assert(s);
+
+ if (streq(s, "es256"))
+ a = COSE_ES256;
+ else if (streq(s, "rs256"))
+ a = COSE_RS256;
+ else if (streq(s, "eddsa"))
+ a = COSE_EDDSA;
+ else
+ return -EINVAL;
+
+ if (ret)
+ *ret = a;
+ return 0;
+}
+#endif