fabrics: add support to connect to accept a PSK

It's possible to specify which PSK stored in the kernel keystore to use.
This means the user has first to insert the key into the store and then
figure out which ID to pass to the connect command because currently
there is no automatic key lookup. This is not simple to make it
work 'correctly' as there potentially a more than one key which matches
the connection description. So this would need some match logic. Let's
not go there for the moment.

Instead, we allow the user to pass the configured key directly from the
connect command.

Signed-off-by: Daniel Wagner <dwagner@suse.de>

fabrics.c

@@ -94,6 +94,7 @@ static const char *nvmf_context		= "execution context identification string";
 
 #define NVMF_ARGS(n, c, ...)                                                                     \
 	struct argconfig_commandline_options n[] = {                                             \
+		__VA_ARGS__,                                                                     \
 		OPT_STRING("transport",       't', "STR", &transport,     nvmf_tport),           \
 		OPT_STRING("nqn",             'n', "STR", &subsysnqn,     nvmf_nqn),             \
 		OPT_STRING("traddr",          'a', "STR", &traddr,        nvmf_traddr),          \
@@ -120,7 +121,6 @@ static const char *nvmf_context		= "execution context identification string";
 		OPT_FLAG("data-digest",       'G', &c.data_digest,        nvmf_data_digest),     \
 		OPT_FLAG("tls",                 0, &c.tls,                nvmf_tls),             \
 		OPT_FLAG("concat",              0, &c.concat,             nvmf_concat),          \
-		__VA_ARGS__,                                                                     \
 		OPT_END()                                                                        \
 	}
 
@@ -904,15 +904,18 @@ int nvmf_connect(const char *desc, int argc, char **argv)
 	nvme_print_flags_t flags;
 	struct nvme_fabrics_config cfg = { 0 };
 	char *format = "normal";
-
+	char *keyring = NULL;
+	char *tls_key = NULL;
 
 	NVMF_ARGS(opts, cfg,
 		  OPT_STRING("dhchap-ctrl-secret", 'C', "STR", &ctrlkey,      nvmf_ctrlkey),
 		  OPT_STRING("config",             'J', "FILE", &config_file, nvmf_config_file),
 		  OPT_INCR("verbose",              'v', &verbose,             "Increase logging verbosity"),
-		  OPT_FLAG("dump-config",          'O', &dump_config,             "Dump JSON configuration to stdout"),
-		  OPT_FMT("output-format",         'o', &format,       "Output format: normal|json"),
-		  OPT_STRING("context",              0, "STR", &context,  nvmf_context));
+		  OPT_FLAG("dump-config",          'O', &dump_config,         "Dump JSON configuration to stdout"),
+		  OPT_FMT("output-format",         'o', &format,              "Output format: normal|json"),
+		  OPT_STRING("context",              0, "STR", &context,      nvmf_context),
+		  OPT_STR("keyring",                 0, &keyring,             "Keyring to store the TLS key, name or keyring id"),
+		  OPT_STR("tls_key",                 0, &tls_key,             "TLS key in PSK Interchagne format or key store id"));
 
 	nvmf_default_config(&cfg);
 
@@ -1008,9 +1011,30 @@ int nvmf_connect(const char *desc, int argc, char **argv)
 		errno = ENOMEM;
 		goto out_free;
 	}
+
 	if (ctrlkey)
 		nvme_ctrl_set_dhchap_key(c, ctrlkey);
 
+	if (keyring) {
+		char *endptr;
+		long id = strtol(keyring, &endptr, 0);
+
+		if (endptr != keyring)
+			cfg.keyring = id;
+		else
+			nvme_ctrl_set_keyring(c, keyring);
+	}
+
+	if (tls_key) {
+		char *endptr;
+		long id = strtol(tls_key, &endptr, 0);
+
+		if (endptr != tls_key)
+			cfg.tls_key = id;
+		else
+			nvme_ctrl_set_tls_key(c, tls_key);
+	}
+
 	errno = 0;
 	ret = nvmf_add_ctrl(h, c, &cfg);
 	if (ret)