daemons/execd/remoted

/* */
This source file includes following definitions.
debug_log
remoted__read_handshake_data
lrmd_remote_client_msg
lrmd_remote_client_destroy
lrmd_auth_timeout_cb
lrmd_remote_listen
lrmd_remote_connection_destroy
lrmd_tls_server_key_cb
bind_and_listen
get_address_info
lrmd_init_remote_tls_server
lrmd_tls_server_destroy
   1 /*
   2  * Copyright 2012-2021 the Pacemaker project contributors
   3  *
   4  * The version control history for this file may have further details.
   5  *
   6  * This source code is licensed under the GNU Lesser General Public License
   7  * version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
   8  */
   9 
  10 #include <crm_internal.h>
  11 
  12 #include <glib.h>
  13 #include <unistd.h>
  14 
  15 #include <crm/crm.h>
  16 #include <crm/msg_xml.h>
  17 #include <crm/crm.h>
  18 #include <crm/msg_xml.h>
  19 #include <crm/common/mainloop.h>
  20 #include <crm/common/remote_internal.h>
  21 #include <crm/lrmd_internal.h>
  22 
  23 #include <netdb.h>
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26 #include <netinet/ip.h>
  27 #include <arpa/inet.h>
  28 
  29 #include "pacemaker-execd.h"
  30 
  31 #ifdef HAVE_GNUTLS_GNUTLS_H
  32 
  33 #  include <gnutls/gnutls.h>
  34 
  35 #  define LRMD_REMOTE_AUTH_TIMEOUT 10000
  36 gnutls_psk_server_credentials_t psk_cred_s;
  37 gnutls_dh_params_t dh_params;
  38 static int ssock = -1;
  39 extern int lrmd_call_id;
  40 
  41 static void
  42 debug_log(int level, const char *str)
     /*  */
  43 {
  44     fputs(str, stderr);
  45 }
  46 
  47 /*!
  48  * \internal
  49  * \brief Read (more) TLS handshake data from client
  50  */
  51 static int
  52 remoted__read_handshake_data(pcmk__client_t *client)
     /*  */
  53 {
  54     int rc = pcmk__read_handshake_data(client);
  55 
  56     if (rc == EAGAIN) {
  57         /* No more data is available at the moment. Just return for now;
  58          * we'll get invoked again once the client sends more.
  59          */
  60         return 0;
  61     } else if (rc != pcmk_rc_ok) {
  62         return -1;
  63     }
  64 
  65     if (client->remote->auth_timeout) {
  66         g_source_remove(client->remote->auth_timeout);
  67     }
  68     client->remote->auth_timeout = 0;
  69 
  70     client->remote->tls_handshake_complete = TRUE;
  71     crm_notice("Remote client connection accepted");
  72 
  73     /* Only a client with access to the TLS key can connect, so we can treat
  74      * it as privileged.
  75      */
  76     pcmk__set_client_flags(client, pcmk__client_privileged);
  77 
  78     // Alert other clients of the new connection
  79     notify_of_new_client(client);
  80     return 0;
  81 }
  82 
  83 static int
  84 lrmd_remote_client_msg(gpointer data)
     /*  */
  85 {
  86     int id = 0;
  87     int rc;
  88     xmlNode *request = NULL;
  89     pcmk__client_t *client = data;
  90 
  91     if (client->remote->tls_handshake_complete == FALSE) {
  92         return remoted__read_handshake_data(client);
  93     }
  94 
  95     switch (pcmk__remote_ready(client->remote, 0)) {
  96         case pcmk_rc_ok:
  97             break;
  98         case ETIME: // No message available to read
  99             return 0;
 100         default:    // Error
 101             crm_info("Remote client disconnected while polling it");
 102             return -1;
 103     }
 104 
 105     rc = pcmk__read_remote_message(client->remote, -1);
 106 
 107     request = pcmk__remote_message_xml(client->remote);
 108     while (request) {
 109         crm_element_value_int(request, F_LRMD_REMOTE_MSG_ID, &id);
 110         crm_trace("Processing remote client request %d", id);
 111         if (!client->name) {
 112             const char *value = crm_element_value(request, F_LRMD_CLIENTNAME);
 113 
 114             if (value) {
 115                 client->name = strdup(value);
 116             }
 117         }
 118 
 119         lrmd_call_id++;
 120         if (lrmd_call_id < 1) {
 121             lrmd_call_id = 1;
 122         }
 123 
 124         crm_xml_add(request, F_LRMD_CLIENTID, client->id);
 125         crm_xml_add(request, F_LRMD_CLIENTNAME, client->name);
 126         crm_xml_add_int(request, F_LRMD_CALLID, lrmd_call_id);
 127 
 128         process_lrmd_message(client, id, request);
 129         free_xml(request);
 130 
 131         /* process all the messages in the current buffer */
 132         request = pcmk__remote_message_xml(client->remote);
 133     }
 134 
 135     if (rc == ENOTCONN) {
 136         crm_info("Remote client disconnected while reading from it");
 137         return -1;
 138     }
 139 
 140     return 0;
 141 }
 142 
 143 static void
 144 lrmd_remote_client_destroy(gpointer user_data)
     /*  */
 145 {
 146     pcmk__client_t *client = user_data;
 147 
 148     if (client == NULL) {
 149         return;
 150     }
 151 
 152     crm_notice("Cleaning up after remote client %s disconnected",
 153                pcmk__client_name(client));
 154 
 155     ipc_proxy_remove_provider(client);
 156 
 157     /* if this is the last remote connection, stop recurring
 158      * operations */
 159     if (pcmk__ipc_client_count() == 1) {
 160         client_disconnect_cleanup(NULL);
 161     }
 162 
 163     if (client->remote->tls_session) {
 164         void *sock_ptr;
 165         int csock;
 166 
 167         sock_ptr = gnutls_transport_get_ptr(*client->remote->tls_session);
 168         csock = GPOINTER_TO_INT(sock_ptr);
 169 
 170         gnutls_bye(*client->remote->tls_session, GNUTLS_SHUT_RDWR);
 171         gnutls_deinit(*client->remote->tls_session);
 172         gnutls_free(client->remote->tls_session);
 173         close(csock);
 174     }
 175 
 176     lrmd_client_destroy(client);
 177     return;
 178 }
 179 
 180 static gboolean
 181 lrmd_auth_timeout_cb(gpointer data)
     /*  */
 182 {
 183     pcmk__client_t *client = data;
 184 
 185     client->remote->auth_timeout = 0;
 186 
 187     if (client->remote->tls_handshake_complete == TRUE) {
 188         return FALSE;
 189     }
 190 
 191     mainloop_del_fd(client->remote->source);
 192     client->remote->source = NULL;
 193     crm_err("Remote client authentication timed out");
 194 
 195     return FALSE;
 196 }
 197 
 198 // Dispatch callback for remote server socket
 199 static int
 200 lrmd_remote_listen(gpointer data)
     /*  */
 201 {
 202     int csock = -1;
 203     gnutls_session_t *session = NULL;
 204     pcmk__client_t *new_client = NULL;
 205 
 206     // For client socket
 207     static struct mainloop_fd_callbacks lrmd_remote_fd_cb = {
 208         .dispatch = lrmd_remote_client_msg,
 209         .destroy = lrmd_remote_client_destroy,
 210     };
 211 
 212     CRM_CHECK(ssock >= 0, return TRUE);
 213 
 214     if (pcmk__accept_remote_connection(ssock, &csock) != pcmk_rc_ok) {
 215         return TRUE;
 216     }
 217 
 218     session = pcmk__new_tls_session(csock, GNUTLS_SERVER, GNUTLS_CRD_PSK,
 219                                     psk_cred_s);
 220     if (session == NULL) {
 221         close(csock);
 222         return TRUE;
 223     }
 224 
 225     new_client = pcmk__new_unauth_client(NULL);
 226     new_client->remote = calloc(1, sizeof(pcmk__remote_t));
 227     pcmk__set_client_flags(new_client, pcmk__client_tls);
 228     new_client->remote->tls_session = session;
 229 
 230     // Require the client to authenticate within this time
 231     new_client->remote->auth_timeout = g_timeout_add(LRMD_REMOTE_AUTH_TIMEOUT,
 232                                                      lrmd_auth_timeout_cb,
 233                                                      new_client);
 234     crm_info("Remote client pending authentication "
 235              CRM_XS " %p id: %s", new_client, new_client->id);
 236 
 237     new_client->remote->source =
 238         mainloop_add_fd("pacemaker-remote-client", G_PRIORITY_DEFAULT, csock,
 239                         new_client, &lrmd_remote_fd_cb);
 240     return TRUE;
 241 }
 242 
 243 static void
 244 lrmd_remote_connection_destroy(gpointer user_data)
     /*  */
 245 {
 246     crm_notice("TLS server session ended");
 247     return;
 248 }
 249 
 250 // \return 0 on success, -1 on error (gnutls_psk_server_credentials_function)
 251 static int
 252 lrmd_tls_server_key_cb(gnutls_session_t session, const char *username, gnutls_datum_t * key)
     /*  */
 253 {
 254     return (lrmd__init_remote_key(key) == pcmk_rc_ok)? 0 : -1;
 255 }
 256 
 257 static int
 258 bind_and_listen(struct addrinfo *addr)
     /*  */
 259 {
 260     int optval;
 261     int fd;
 262     int rc;
 263     char buffer[INET6_ADDRSTRLEN] = { 0, };
 264 
 265     pcmk__sockaddr2str(addr->ai_addr, buffer);
 266     crm_trace("Attempting to bind to address %s", buffer);
 267 
 268     fd = socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
 269     if (fd < 0) {
 270         crm_perror(LOG_ERR, "Listener socket creation failed");
 271         return -1;
 272     }
 273 
 274     /* reuse address */
 275     optval = 1;
 276     rc = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval));
 277     if (rc < 0) {
 278         crm_perror(LOG_ERR, "Local address reuse not allowed on %s", buffer);
 279         close(fd);
 280         return -1;
 281     }
 282 
 283     if (addr->ai_family == AF_INET6) {
 284         optval = 0;
 285         rc = setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &optval, sizeof(optval));
 286         if (rc < 0) {
 287             crm_perror(LOG_INFO, "Couldn't disable IPV6-only on %s", buffer);
 288             close(fd);
 289             return -1;
 290         }
 291     }
 292 
 293     if (bind(fd, addr->ai_addr, addr->ai_addrlen) != 0) {
 294         crm_perror(LOG_ERR, "Cannot bind to %s", buffer);
 295         close(fd);
 296         return -1;
 297     }
 298 
 299     if (listen(fd, 10) == -1) {
 300         crm_perror(LOG_ERR, "Cannot listen on %s", buffer);
 301         close(fd);
 302         return -1;
 303     }
 304     return fd;
 305 }
 306 
 307 static int
 308 get_address_info(const char *bind_name, int port, struct addrinfo **res)
     /*  */
 309 {
 310     int rc;
 311     char port_str[6]; // at most "65535"
 312     struct addrinfo hints;
 313 
 314     memset(&hints, 0, sizeof(struct addrinfo));
 315     hints.ai_flags = AI_PASSIVE;
 316     hints.ai_family = AF_UNSPEC; // IPv6 or IPv4
 317     hints.ai_socktype = SOCK_STREAM;
 318     hints.ai_protocol = IPPROTO_TCP;
 319 
 320     snprintf(port_str, sizeof(port_str), "%d", port);
 321     rc = getaddrinfo(bind_name, port_str, &hints, res);
 322     if (rc) {
 323         crm_err("Unable to get IP address(es) for %s: %s",
 324                 (bind_name? bind_name : "local node"), gai_strerror(rc));
 325         return -EADDRNOTAVAIL;
 326     }
 327     return pcmk_ok;
 328 }
 329 
 330 int
 331 lrmd_init_remote_tls_server()
     /*  */
 332 {
 333     int filter;
 334     int port = crm_default_remote_port();
 335     struct addrinfo *res = NULL, *iter;
 336     gnutls_datum_t psk_key = { NULL, 0 };
 337     const char *bind_name = getenv("PCMK_remote_address");
 338 
 339     static struct mainloop_fd_callbacks remote_listen_fd_callbacks = {
 340         .dispatch = lrmd_remote_listen,
 341         .destroy = lrmd_remote_connection_destroy,
 342     };
 343 
 344     CRM_CHECK(ssock == -1, return ssock);
 345 
 346     crm_debug("Starting TLS listener on %s port %d",
 347               (bind_name? bind_name : "all addresses on"), port);
 348     crm_gnutls_global_init();
 349     gnutls_global_set_log_function(debug_log);
 350 
 351     if (pcmk__init_tls_dh(&dh_params) != pcmk_rc_ok) {
 352         return -1;
 353     }
 354     gnutls_psk_allocate_server_credentials(&psk_cred_s);
 355     gnutls_psk_set_server_credentials_function(psk_cred_s, lrmd_tls_server_key_cb);
 356     gnutls_psk_set_server_dh_params(psk_cred_s, dh_params);
 357 
 358     /* The key callback won't get called until the first client connection
 359      * attempt. Do it once here, so we can warn the user at start-up if we can't
 360      * read the key. We don't error out, though, because it's fine if the key is
 361      * going to be added later.
 362      */
 363     if (lrmd__init_remote_key(&psk_key) != pcmk_rc_ok) {
 364         crm_warn("A cluster connection will not be possible until the key is available");
 365     }
 366     gnutls_free(psk_key.data);
 367 
 368     if (get_address_info(bind_name, port, &res) != pcmk_ok) {
 369         return -1;
 370     }
 371 
 372     /* Currently we listen on only one address from the resulting list (the
 373      * first IPv6 address we can bind to if possible, otherwise the first IPv4
 374      * address we can bind to). When bind_name is NULL, this should be the
 375      * respective wildcard address.
 376      *
 377      * @TODO If there is demand for specifying more than one address, allow
 378      * bind_name to be a space-separated list, call getaddrinfo() for each,
 379      * and create a socket for each result (set IPV6_V6ONLY on IPv6 sockets
 380      * since IPv4 listeners will have their own sockets).
 381      */
 382     iter = res;
 383     filter = AF_INET6;
 384     while (iter) {
 385         if (iter->ai_family == filter) {
 386             ssock = bind_and_listen(iter);
 387         }
 388         if (ssock != -1) {
 389             break;
 390         }
 391 
 392         iter = iter->ai_next;
 393         if (iter == NULL && filter == AF_INET6) {
 394             iter = res;
 395             filter = AF_INET;
 396         }
 397     }
 398 
 399     if (ssock >= 0) {
 400         mainloop_add_fd("pacemaker-remote-server", G_PRIORITY_DEFAULT, ssock,
 401                         NULL, &remote_listen_fd_callbacks);
 402         crm_debug("Started TLS listener on %s port %d",
 403                   (bind_name? bind_name : "all addresses on"), port);
 404     }
 405     freeaddrinfo(res);
 406     return ssock;
 407 }
 408 
 409 void
 410 lrmd_tls_server_destroy(void)
     /*  */
 411 {
 412     if (psk_cred_s) {
 413         gnutls_psk_free_server_credentials(psk_cred_s);
 414         psk_cred_s = 0;
 415     }
 416 
 417     if (ssock >= 0) {
 418         close(ssock);
 419         ssock = -1;
 420     }
 421 }
 422 #endif
/* */
root/daemons/execd/remoted_tls.c

DEFINITIONS
