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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 09:54:46 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 09:54:46 +0000
commitcd7b005519ade8ab6c97fcb21590b71b7d1be6e3 (patch)
treec611a8d0cd5e8f68f41b8c2d16ba580e0f40a38d /rtrlib/transport/ssh/ssh_transport.c
parentInitial commit. (diff)
downloadlibrtr-upstream.tar.xz
librtr-upstream.zip
Adding upstream version 0.8.0.upstream/0.8.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'rtrlib/transport/ssh/ssh_transport.c')
-rw-r--r--rtrlib/transport/ssh/ssh_transport.c392
1 files changed, 392 insertions, 0 deletions
diff --git a/rtrlib/transport/ssh/ssh_transport.c b/rtrlib/transport/ssh/ssh_transport.c
new file mode 100644
index 0000000..222ea25
--- /dev/null
+++ b/rtrlib/transport/ssh/ssh_transport.c
@@ -0,0 +1,392 @@
+/*
+ * This file is part of RTRlib.
+ *
+ * This file is subject to the terms and conditions of the MIT license.
+ * See the file LICENSE in the top level directory for more details.
+ *
+ * Website: http://rtrlib.realmv6.org/
+ */
+
+#include "ssh_transport_private.h"
+
+#include "rtrlib/lib/alloc_utils_private.h"
+#include "rtrlib/lib/log_private.h"
+#include "rtrlib/lib/utils_private.h"
+#include "rtrlib/rtrlib_export_private.h"
+#include "rtrlib/transport/transport_private.h"
+
+#include <assert.h>
+#include <errno.h>
+#include <libssh/libssh.h>
+#include <pthread.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+
+#define SSH_DBG(fmt, sock, ...) \
+ do { \
+ const struct tr_ssh_socket *tmp = sock; \
+ lrtr_dbg("SSH Transport(%s@%s:%u): " fmt, tmp->config.username, tmp->config.host, tmp->config.port, \
+ ##__VA_ARGS__); \
+ } while (0)
+#define SSH_DBG1(a, sock) SSH_DBG(a, sock)
+
+struct tr_ssh_socket {
+ ssh_session session;
+ ssh_channel channel;
+ struct tr_ssh_config config;
+ char *ident;
+};
+
+static int tr_ssh_open(void *tr_ssh_sock);
+static void tr_ssh_close(void *tr_ssh_sock);
+static void tr_ssh_free(struct tr_socket *tr_sock);
+static int tr_ssh_recv(const void *tr_ssh_sock, void *buf, const size_t buf_len, const time_t timeout);
+static int tr_ssh_send(const void *tr_ssh_sock, const void *pdu, const size_t len, const time_t timeout);
+static int tr_ssh_recv_async(const struct tr_ssh_socket *tr_ssh_sock, void *buf, const size_t buf_len);
+static const char *tr_ssh_ident(void *tr_ssh_sock);
+
+/* WARNING: This function has cancelable sections! */
+int tr_ssh_open(void *socket)
+{
+ struct tr_ssh_socket *ssh_socket = socket;
+ const struct tr_ssh_config *config = &ssh_socket->config;
+
+ assert(!ssh_socket->channel);
+ assert(!ssh_socket->session);
+
+ ssh_socket->session = ssh_new();
+ if (!ssh_socket->session) {
+ SSH_DBG("%s: can't create ssh_session", ssh_socket, __func__);
+ goto error;
+ }
+
+ const int verbosity = SSH_LOG_NOLOG;
+
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_LOG_VERBOSITY, &verbosity);
+
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_HOST, config->host);
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_PORT, &(config->port));
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_BINDADDR, config->bindaddr);
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_USER, config->username);
+
+ if (config->server_hostkey_path)
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_KNOWNHOSTS, config->server_hostkey_path);
+
+ if (config->client_privkey_path)
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_IDENTITY, config->client_privkey_path);
+ if (config->new_socket) {
+ int fd;
+
+ fd = config->new_socket(config->data);
+ if (fd >= 0) {
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_FD, &fd);
+ } else {
+ SSH_DBG1("tr_ssh_init: opening SSH connection failed", ssh_socket);
+ goto error;
+ }
+ }
+
+ ssh_set_blocking(ssh_socket->session, 0);
+ int ret;
+
+ do {
+ ret = ssh_connect(ssh_socket->session);
+
+ if (ret == SSH_ERROR) {
+ SSH_DBG("%s: opening SSH connection failed", ssh_socket, __func__);
+ goto error;
+ } else if (ret == SSH_AGAIN) {
+ socket_t fd = ssh_get_fd(ssh_socket->session);
+
+ fd_set rfds;
+
+ FD_ZERO(&rfds);
+ FD_SET(fd, &rfds);
+ struct timeval timeout = {.tv_sec = ssh_socket->config.connect_timeout, .tv_usec = 0};
+ int oldcancelstate;
+
+ /* Enable cancellability for the select call
+ * to prevent rtr_stop from blocking for a long time.
+ * It must be the only blocking call in this function.
+ * Since local resources have all been freed this should be safe.
+ */
+ pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldcancelstate);
+ int sret = select(fd + 1, &rfds, NULL, NULL, &timeout);
+
+ pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldcancelstate);
+
+ if (sret < 0) {
+ SSH_DBG("could not select ssh socket, %s", ssh_socket, strerror(errno));
+
+ } else if (sret == 0) {
+ SSH_DBG1("connection attempt timed out", ssh_socket);
+ goto error;
+ }
+ }
+
+ } while (ret != SSH_OK);
+
+ ssh_set_blocking(ssh_socket->session, 1);
+
+ // check server identity
+#if LIBSSH_VERSION_MAJOR > 0 || LIBSSH_VERSION_MINOR > 8
+ if ((config->server_hostkey_path) && (ssh_session_is_known_server(ssh_socket->session) != SSH_KNOWN_HOSTS_OK)) {
+#else
+ if ((config->server_hostkey_path) && (ssh_is_server_known(ssh_socket->session) != SSH_SERVER_KNOWN_OK)) {
+#endif
+ SSH_DBG("%s: Wrong hostkey", ssh_socket, __func__);
+ goto error;
+ }
+
+ if (config->client_privkey_path) {
+ SSH_DBG("%s: Trying publickey authentication", ssh_socket, __func__);
+ ssh_options_set(ssh_socket->session, SSH_OPTIONS_IDENTITY, config->client_privkey_path);
+
+ int rtval;
+
+#if LIBSSH_VERSION_MAJOR > 0 || LIBSSH_VERSION_MINOR > 5
+ rtval = ssh_userauth_publickey_auto(ssh_socket->session, NULL, NULL);
+#else /* else use libSSH version 0.5.0 */
+ rtval = ssh_userauth_autopubkey(ssh_socket->session, NULL);
+#endif
+ if (rtval != SSH_AUTH_SUCCESS) {
+ SSH_DBG("%s: Publickey authentication failed", ssh_socket, __func__);
+ goto error;
+ }
+
+ } else {
+ SSH_DBG("%s: Trying password authentication", ssh_socket, __func__);
+
+ if (ssh_userauth_password(ssh_socket->session, NULL, config->password) != SSH_AUTH_SUCCESS) {
+ SSH_DBG("%s: Password authentication failed", ssh_socket, __func__);
+ goto error;
+ }
+ }
+
+ ssh_socket->channel = ssh_channel_new(ssh_socket->session);
+ if (!ssh_socket->channel)
+ goto error;
+
+ if (ssh_channel_open_session(ssh_socket->channel) == SSH_ERROR)
+ goto error;
+
+ if (ssh_channel_request_subsystem(ssh_socket->channel, "rpki-rtr") == SSH_ERROR) {
+ SSH_DBG("%s: Error requesting subsystem rpki-rtr", ssh_socket, __func__);
+ goto error;
+ }
+ SSH_DBG1("Connection established", ssh_socket);
+
+ return TR_SUCCESS;
+
+error:
+ tr_ssh_close(ssh_socket);
+ return TR_ERROR;
+}
+
+void tr_ssh_close(void *tr_ssh_sock)
+{
+ struct tr_ssh_socket *socket = tr_ssh_sock;
+
+ if (socket->channel) {
+ if (ssh_channel_is_open(socket->channel))
+ ssh_channel_close(socket->channel);
+ ssh_channel_free(socket->channel);
+ socket->channel = NULL;
+ }
+ if (socket->session) {
+ ssh_disconnect(socket->session);
+ ssh_free(socket->session);
+ socket->session = NULL;
+ }
+ SSH_DBG1("Socket closed", socket);
+}
+
+void tr_ssh_free(struct tr_socket *tr_sock)
+{
+ struct tr_ssh_socket *tr_ssh_sock = tr_sock->socket;
+
+ assert(!tr_ssh_sock->channel);
+ assert(!tr_ssh_sock->session);
+
+ SSH_DBG1("Freeing socket", tr_ssh_sock);
+
+ lrtr_free(tr_ssh_sock->config.host);
+ lrtr_free(tr_ssh_sock->config.bindaddr);
+ lrtr_free(tr_ssh_sock->config.username);
+ lrtr_free(tr_ssh_sock->config.client_privkey_path);
+ lrtr_free(tr_ssh_sock->config.server_hostkey_path);
+
+ if (tr_ssh_sock->ident)
+ lrtr_free(tr_ssh_sock->ident);
+ lrtr_free(tr_ssh_sock);
+ tr_sock->socket = NULL;
+}
+
+int tr_ssh_recv_async(const struct tr_ssh_socket *tr_ssh_sock, void *buf, const size_t buf_len)
+{
+ const int rtval = ssh_channel_read_nonblocking(tr_ssh_sock->channel, buf, buf_len, false);
+
+ if (rtval == 0) {
+ if (ssh_channel_is_eof(tr_ssh_sock->channel) != 0) {
+ SSH_DBG1("remote has sent EOF", tr_ssh_sock);
+ return TR_CLOSED;
+ } else {
+ return TR_WOULDBLOCK;
+ }
+ } else if (rtval == SSH_ERROR) {
+ SSH_DBG1("recv(..) error", tr_ssh_sock);
+ return TR_ERROR;
+ }
+ return rtval;
+}
+
+int tr_ssh_recv(const void *tr_ssh_sock, void *buf, const size_t buf_len, const time_t timeout)
+{
+ ssh_channel rchans[2] = {((struct tr_ssh_socket *)tr_ssh_sock)->channel, NULL};
+ struct timeval timev = {timeout, 0};
+ int ret;
+
+ ret = ssh_channel_select(rchans, NULL, NULL, &timev);
+ if (ret == SSH_EINTR)
+ return TR_INTR;
+ else if (ret == SSH_ERROR)
+ return TR_ERROR;
+
+ if (ssh_channel_is_eof(((struct tr_ssh_socket *)tr_ssh_sock)->channel) != 0)
+ return TR_ERROR;
+
+ if (!rchans[0])
+ return TR_WOULDBLOCK;
+
+ return tr_ssh_recv_async(tr_ssh_sock, buf, buf_len);
+}
+
+int tr_ssh_send(const void *tr_ssh_sock, const void *pdu, const size_t len,
+ const time_t timeout __attribute__((unused)))
+{
+ int ret = ssh_channel_write(((struct tr_ssh_socket *)tr_ssh_sock)->channel, pdu, len);
+
+ if (ret == SSH_ERROR)
+ return TR_ERROR;
+
+ return ret;
+}
+
+const char *tr_ssh_ident(void *tr_ssh_sock)
+{
+ size_t len;
+ struct tr_ssh_socket *sock = tr_ssh_sock;
+
+ assert(sock);
+
+ if (sock->ident)
+ return sock->ident;
+
+ len = strlen(sock->config.username) + 1 + strlen(sock->config.host) + 1 + 5 + 1;
+ sock->ident = lrtr_malloc(len);
+ if (!sock->ident)
+ return NULL;
+ snprintf(sock->ident, len, "%s@%s:%u", sock->config.username, sock->config.host, sock->config.port);
+ return sock->ident;
+}
+
+RTRLIB_EXPORT int tr_ssh_init(const struct tr_ssh_config *config, struct tr_socket *socket)
+{
+ socket->close_fp = &tr_ssh_close;
+ socket->free_fp = &tr_ssh_free;
+ socket->open_fp = &tr_ssh_open;
+ socket->recv_fp = &tr_ssh_recv;
+ socket->send_fp = &tr_ssh_send;
+ socket->ident_fp = &tr_ssh_ident;
+
+ socket->socket = lrtr_calloc(1, sizeof(struct tr_ssh_socket));
+ struct tr_ssh_socket *ssh_socket = socket->socket;
+
+ ssh_socket->channel = NULL;
+ ssh_socket->session = NULL;
+ ssh_socket->config.host = lrtr_strdup(config->host);
+ if (!ssh_socket->config.host)
+ goto error;
+ ssh_socket->config.port = config->port;
+
+ ssh_socket->config.username = lrtr_strdup(config->username);
+ if (!ssh_socket->config.username)
+ goto error;
+
+ if ((config->password && config->client_privkey_path) || (!config->password && !config->client_privkey_path))
+ return TR_ERROR;
+
+ if (config->bindaddr) {
+ ssh_socket->config.bindaddr = lrtr_strdup(config->bindaddr);
+
+ if (!ssh_socket->config.bindaddr)
+ goto error;
+
+ } else {
+ ssh_socket->config.bindaddr = NULL;
+ }
+
+ if (config->client_privkey_path) {
+ ssh_socket->config.client_privkey_path = lrtr_strdup(config->client_privkey_path);
+ if (!ssh_socket->config.client_privkey_path)
+ goto error;
+
+ } else {
+ ssh_socket->config.client_privkey_path = NULL;
+ }
+
+ if (config->server_hostkey_path) {
+ ssh_socket->config.server_hostkey_path = lrtr_strdup(config->server_hostkey_path);
+
+ if (!ssh_socket->config.client_privkey_path)
+ goto error;
+
+ } else {
+ ssh_socket->config.server_hostkey_path = NULL;
+ }
+
+ if (config->connect_timeout == 0)
+ ssh_socket->config.connect_timeout = RTRLIB_TRANSPORT_CONNECT_TIMEOUT_DEFAULT;
+ else
+ ssh_socket->config.connect_timeout = config->connect_timeout;
+
+ if (config->password) {
+ ssh_socket->config.password = lrtr_strdup(config->password);
+
+ if (!ssh_socket->config.password)
+ goto error;
+
+ } else {
+ ssh_socket->config.password = NULL;
+ }
+
+ ssh_socket->ident = NULL;
+ ssh_socket->config.data = config->data;
+ ssh_socket->config.new_socket = config->new_socket;
+
+ return TR_SUCCESS;
+
+error:
+ if (ssh_socket->config.host)
+ free(ssh_socket->config.host);
+
+ if (ssh_socket->config.username)
+ free(ssh_socket->config.username);
+
+ if (ssh_socket->config.bindaddr)
+ free(ssh_socket->config.bindaddr);
+
+ if (ssh_socket->config.client_privkey_path)
+ free(ssh_socket->config.client_privkey_path);
+
+ if (ssh_socket->config.server_hostkey_path)
+ free(ssh_socket->config.server_hostkey_path);
+
+ if (ssh_socket->config.password)
+ free(ssh_socket->config.password);
+
+ return TR_ERROR;
+}