blob: d824324e74b904bd131e4383a63a2572ff2f3e3d [file] [log] [blame]
/*
* Copyright (C) 2019 CESNET, https://photonics.cesnet.cz/
*
* Written by Václav Kubernát <kubernat@cesnet.cz>
* Written by Jan Kundrát <jan.kundrat@cesnet.cz>
*
*/
#include <cstring>
#include <libyang/Tree_Data.hpp>
#include <mutex>
extern "C" {
#include <nc_client.h>
}
#include <sstream>
#include "netconf-client.hpp"
#include "UniqueResource.hpp"
namespace libnetconf {
namespace impl {
/** @short Initialization of the libnetconf2 library client
Just a safe wrapper over nc_client_init and nc_client_destroy, really.
*/
class ClientInit {
ClientInit()
{
nc_client_init();
nc_verbosity(NC_VERB_DEBUG);
}
~ClientInit()
{
nc_client_destroy();
}
public:
static ClientInit& instance()
{
static ClientInit lib;
return lib;
}
ClientInit(const ClientInit&) = delete;
ClientInit(ClientInit&&) = delete;
ClientInit& operator=(const ClientInit&) = delete;
ClientInit& operator=(ClientInit&&) = delete;
};
static std::mutex clientOptions;
inline void custom_free_nc_reply_data(nc_reply_data* reply)
{
nc_reply_free(reinterpret_cast<nc_reply*>(reply));
}
inline void custom_free_nc_reply_error(nc_reply_error* reply)
{
nc_reply_free(reinterpret_cast<nc_reply*>(reply));
}
char *ssh_auth_interactive_cb(const char *auth_name, const char *instruction, const char *prompt, int echo, void *priv)
{
const auto cb = static_cast<const client::KbdInteractiveCb*>(priv);
auto res = (*cb)(auth_name, instruction, prompt, echo);
return ::strdup(res.c_str());
}
template <auto fn>
using deleter_from_fn = std::integral_constant<decltype(fn), fn>;
template <typename T>
struct deleter_type_for {
using func_type = void (*)(T*);
};
template <typename T>
struct deleter_for {
};
template <>
struct deleter_for<struct nc_rpc> {
static constexpr void (*free)(struct nc_rpc*) = deleter_from_fn<nc_rpc_free>();
};
template <>
struct deleter_for<struct nc_reply> {
static constexpr void (*free)(struct nc_reply*) = deleter_from_fn<nc_reply_free>();
};
template <>
struct deleter_for<struct nc_reply_data> {
static constexpr void (*free)(struct nc_reply_data*) = deleter_from_fn<custom_free_nc_reply_data>();
};
template <>
struct deleter_for<struct nc_reply_error> {
static constexpr void (*free)(struct nc_reply_error*) = deleter_from_fn<custom_free_nc_reply_error>();
};
template <typename T>
using unique_ptr_for = std::unique_ptr<T, decltype(deleter_for<T>::free)>;
template <typename T>
auto guarded(T* ptr)
{
return unique_ptr_for<T>(ptr, deleter_for<T>::free);
}
unique_ptr_for<struct nc_reply> do_rpc(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
{
uint64_t msgid;
NC_MSG_TYPE msgtype;
msgtype = nc_send_rpc(session->session_internal(), rpc.get(), 1000, &msgid);
if (msgtype == NC_MSG_ERROR) {
throw std::runtime_error{"Failed to send RPC"};
}
if (msgtype == NC_MSG_WOULDBLOCK) {
throw std::runtime_error{"Timeout sending an RPC"};
}
struct nc_reply* raw_reply;
while (true) {
msgtype = nc_recv_reply(session->session_internal(), rpc.get(), msgid, 20000, LYD_OPT_DESTRUCT | LYD_OPT_NOSIBLINGS, &raw_reply);
auto reply = guarded(raw_reply);
raw_reply = nullptr;
switch (msgtype) {
case NC_MSG_ERROR:
throw std::runtime_error{"Failed to receive an RPC reply"};
case NC_MSG_WOULDBLOCK:
throw std::runtime_error{"Timed out waiting for RPC reply"};
case NC_MSG_REPLY_ERR_MSGID:
throw std::runtime_error{"Received a wrong reply -- msgid mismatch"};
case NC_MSG_NOTIF:
continue;
default:
return reply;
}
}
__builtin_unreachable();
}
client::ReportedError make_error(unique_ptr_for<struct nc_reply>&& reply)
{
if (reply->type != NC_RPL_ERROR) {
throw std::logic_error{"Cannot extract an error from a non-error server reply"};
}
auto errorReply = guarded(reinterpret_cast<struct nc_reply_error*>(reply.release()));
// TODO: capture the error details, not just that human-readable string
std::ostringstream ss;
ss << "Server error:" << std::endl;
for (uint32_t i = 0; i < errorReply->count; ++i) {
const auto e = errorReply->err[i];
ss << " #" << i << ": " << e.message;
if (e.path) {
ss << " (XPath " << e.path << ")";
}
ss << std::endl;
}
return client::ReportedError{ss.str()};
}
std::optional<unique_ptr_for<struct nc_reply_data>> do_rpc_data_or_ok(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
{
auto x = do_rpc(session, std::move(rpc));
switch (x->type) {
case NC_RPL_DATA:
return guarded(reinterpret_cast<struct nc_reply_data*>(x.release()));
case NC_RPL_OK:
return std::nullopt;
case NC_RPL_ERROR:
throw make_error(std::move(x));
default:
throw std::runtime_error{"Unhandled reply type"};
}
}
unique_ptr_for<struct nc_reply_data> do_rpc_data(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
{
auto x = do_rpc_data_or_ok(session, std::move(rpc));
if (!x) {
throw std::runtime_error{"Received OK instead of a data reply"};
}
return std::move(*x);
}
void do_rpc_ok(client::Session* session, unique_ptr_for<struct nc_rpc>&& rpc)
{
auto x = do_rpc_data_or_ok(session, std::move(rpc));
if (x) {
throw std::runtime_error{"Unexpected DATA reply"};
}
}
}
namespace client {
struct nc_session* Session::session_internal()
{
return m_session;
}
libyang::S_Context Session::libyangContext()
{
return std::make_shared<libyang::Context>(nc_session_get_ctx(m_session), nullptr);
}
Session::Session(struct nc_session* session)
: m_session(session)
{
impl::ClientInit::instance();
}
Session::~Session()
{
::nc_session_free(m_session, nullptr);
}
std::unique_ptr<Session> Session::connectPubkey(const std::string& host, const uint16_t port, const std::string& user, const std::string& pubPath, const std::string& privPath)
{
impl::ClientInit::instance();
{
// FIXME: this is still horribly not enough. libnetconf *must* provide us with something better.
std::lock_guard lk(impl::clientOptions);
nc_client_ssh_set_username(user.c_str());
nc_client_ssh_set_auth_pref(NC_SSH_AUTH_PUBLICKEY, 5);
nc_client_ssh_add_keypair(pubPath.c_str(), privPath.c_str());
}
auto session = std::make_unique<Session>(nc_connect_ssh(host.c_str(), port, nullptr));
if (!session->m_session) {
throw std::runtime_error{"nc_connect_ssh failed"};
}
return session;
}
std::unique_ptr<Session> Session::connectKbdInteractive(const std::string& host, const uint16_t port, const std::string& user, const KbdInteractiveCb& callback)
{
impl::ClientInit::instance();
std::lock_guard lk(impl::clientOptions);
auto cb_guard = make_unique_resource([user, &callback]() {
nc_client_ssh_set_username(user.c_str());
nc_client_ssh_set_auth_pref(NC_SSH_AUTH_INTERACTIVE, 5);
nc_client_ssh_set_auth_interactive_clb(impl::ssh_auth_interactive_cb, static_cast<void *>(&const_cast<KbdInteractiveCb&>(callback)));
}, []() {
nc_client_ssh_set_auth_interactive_clb(nullptr, nullptr);
nc_client_ssh_set_username(nullptr);
});
auto session = std::make_unique<Session>(nc_connect_ssh(host.c_str(), port, nullptr));
if (!session->m_session) {
throw std::runtime_error{"nc_connect_ssh failed"};
}
return session;
}
std::unique_ptr<Session> Session::connectSocket(const std::string& path)
{
impl::ClientInit::instance();
auto session = std::make_unique<Session>(nc_connect_unix(path.c_str(), nullptr));
if (!session->m_session) {
throw std::runtime_error{"nc_connect_unix failed"};
}
return session;
}
std::vector<std::string_view> Session::capabilities() const
{
std::vector<std::string_view> res;
auto caps = nc_session_get_cpblts(m_session);
while (*caps) {
res.emplace_back(*caps);
++caps;
}
return res;
}
std::shared_ptr<libyang::Data_Node> Session::get(const std::optional<std::string>& filter)
{
auto rpc = impl::guarded(nc_rpc_get(filter ? filter->c_str() : nullptr, NC_WD_ALL, NC_PARAMTYPE_CONST));
if (!rpc) {
throw std::runtime_error("Cannot create get RPC");
}
auto reply = impl::do_rpc_data(this, std::move(rpc));
auto dataNode = libyang::create_new_Data_Node(reply->data);
// TODO: can we do without copying?
// If we just default-construct a new node (or use the create_new_Data_Node) and then set reply->data to nullptr,
// there are mem leaks and even libnetconf2 complains loudly.
return dataNode ? dataNode->dup_withsiblings(1) : nullptr;
}
std::string Session::getSchema(const std::string_view identifier, const std::optional<std::string_view> version)
{
auto rpc = impl::guarded(nc_rpc_getschema(identifier.data(), version ? version.value().data() : nullptr, nullptr, NC_PARAMTYPE_CONST));
if (!rpc) {
throw std::runtime_error("Cannot create get-schema RPC");
}
auto reply = impl::do_rpc_data(this, std::move(rpc));
auto node = libyang::create_new_Data_Node(reply->data)->dup_withsiblings(1);
auto set = node->find_path("data");
for (auto node : set->data()) {
if (node->schema()->nodetype() == LYS_ANYXML) {
libyang::Data_Node_Anydata anydata(node);
return anydata.value().str;
}
}
throw std::runtime_error("Got a reply to get-schema, but it didn't contain the required schema");
}
std::shared_ptr<libyang::Data_Node> Session::getConfig(const NC_DATASTORE datastore, const std::optional<const std::string> filter)
{
auto rpc = impl::guarded(nc_rpc_getconfig(datastore, filter ? filter->c_str() : nullptr, NC_WD_ALL, NC_PARAMTYPE_CONST));
if (!rpc) {
throw std::runtime_error("Cannot create get-config RPC");
}
auto reply = impl::do_rpc_data(this, std::move(rpc));
auto dataNode = libyang::create_new_Data_Node(reply->data);
// TODO: can we do without copying? See Session::get() for details.
return dataNode ? dataNode->dup_withsiblings(1) : nullptr;
}
void Session::editConfig(const NC_DATASTORE datastore,
const NC_RPC_EDIT_DFLTOP defaultOperation,
const NC_RPC_EDIT_TESTOPT testOption,
const NC_RPC_EDIT_ERROPT errorOption,
const std::string& data)
{
auto rpc = impl::guarded(nc_rpc_edit(datastore, defaultOperation, testOption, errorOption, data.c_str(), NC_PARAMTYPE_CONST));
if (!rpc) {
throw std::runtime_error("Cannot create edit-config RPC");
}
impl::do_rpc_ok(this, std::move(rpc));
}
void Session::copyConfigFromString(const NC_DATASTORE target, const std::string& data)
{
auto rpc = impl::guarded(nc_rpc_copy(target, nullptr, target /* yeah, cannot be 0... */, data.c_str(), NC_WD_UNKNOWN, NC_PARAMTYPE_CONST));
if (!rpc) {
throw std::runtime_error("Cannot create copy-config RPC");
}
impl::do_rpc_ok(this, std::move(rpc));
}
void Session::commit()
{
auto rpc = impl::guarded(nc_rpc_commit(1, /* "Optional confirm timeout" how do you optional an uint32_t? */ 0, nullptr, nullptr, NC_PARAMTYPE_CONST));
if (!rpc) {
throw std::runtime_error("Cannot create commit RPC");
}
impl::do_rpc_ok(this, std::move(rpc));
}
void Session::discard()
{
auto rpc = impl::guarded(nc_rpc_discard());
if (!rpc) {
throw std::runtime_error("Cannot create discard RPC");
}
impl::do_rpc_ok(this, std::move(rpc));
}
std::shared_ptr<libyang::Data_Node> Session::rpc(const std::string& xmlData)
{
auto rpc = impl::guarded(nc_rpc_act_generic_xml(xmlData.c_str(), NC_PARAMTYPE_CONST));
if (!rpc) {
throw std::runtime_error("Cannot create generic RPC");
}
auto reply = impl::do_rpc_data_or_ok(this, std::move(rpc));
if (reply) {
auto dataNode = libyang::create_new_Data_Node((*reply)->data);
return dataNode->dup_withsiblings(1);
} else {
return nullptr;
}
}
void Session::copyConfig(const NC_DATASTORE source, const NC_DATASTORE destination)
{
auto rpc = impl::guarded(nc_rpc_copy(destination, nullptr, source, nullptr, NC_WD_UNKNOWN, NC_PARAMTYPE_CONST));
if (!rpc) {
throw std::runtime_error("Cannot create copy-config RPC");
}
impl::do_rpc_ok(this, std::move(rpc));
}
ReportedError::ReportedError(const std::string& what)
: std::runtime_error(what)
{
}
ReportedError::~ReportedError() = default;
}
}