1 /* 2 * Copyright 2004-2020 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 #ifndef CRM_COMMON_IPC__H 11 # define CRM_COMMON_IPC__H 12 13 #ifdef __cplusplus 14 extern "C" { 15 #endif 16 17 /** 18 * \file 19 * \brief IPC interface to Pacemaker daemons 20 * 21 * \ingroup core 22 */ 23 24 #include <sys/uio.h> 25 #include <qb/qbipcc.h> 26 #include <crm/common/xml.h> 27 28 /* 29 * Message creation utilities 30 * 31 * These are used for both IPC messages and cluster layer messages. However, 32 * since this is public API, they stay in this header for backward 33 * compatibility. 34 */ 35 36 #define create_reply(request, xml_response_data) \ 37 create_reply_adv(request, xml_response_data, __func__) 38 39 xmlNode *create_reply_adv(xmlNode *request, xmlNode *xml_response_data, 40 const char *origin); 41 42 #define create_request(task, xml_data, host_to, sys_to, sys_from, uuid_from) \ 43 create_request_adv(task, xml_data, host_to, sys_to, sys_from, uuid_from, \ 44 __func__) 45 46 xmlNode *create_request_adv(const char *task, xmlNode *xml_data, 47 const char *host_to, const char *sys_to, 48 const char *sys_from, const char *uuid_from, 49 const char *origin); 50 51 52 /* 53 * The library supports two methods of creating IPC connections. The older code 54 * allows connecting to any arbitrary IPC name. The newer code only allows 55 * connecting to one of the Pacemaker daemons. 56 * 57 * As daemons are converted to use the new model, the old functions should be 58 * considered deprecated for use with those daemons. Once all daemons are 59 * converted, the old functions should be officially deprecated as public API 60 * and eventually made internal API. 61 */ 62 63 /* 64 * Pacemaker daemon IPC 65 */ 66 67 //! Available IPC interfaces 68 enum pcmk_ipc_server { 69 pcmk_ipc_attrd, //!< Attribute manager 70 pcmk_ipc_based, //!< CIB manager 71 pcmk_ipc_controld, //!< Controller 72 pcmk_ipc_execd, //!< Executor 73 pcmk_ipc_fenced, //!< Fencer 74 pcmk_ipc_pacemakerd, //!< Launcher 75 pcmk_ipc_schedulerd, //!< Scheduler 76 }; 77 78 //! Possible event types that an IPC event callback can be called for 79 enum pcmk_ipc_event { 80 pcmk_ipc_event_connect, //!< Result of asynchronous connection attempt 81 pcmk_ipc_event_disconnect, //!< Termination of IPC connection 82 pcmk_ipc_event_reply, //!< Daemon's reply to client IPC request 83 pcmk_ipc_event_notify, //!< Notification from daemon 84 }; 85 86 //! How IPC replies should be dispatched 87 enum pcmk_ipc_dispatch { 88 pcmk_ipc_dispatch_main, //!< Attach IPC to GMainLoop for dispatch 89 pcmk_ipc_dispatch_poll, //!< Caller will poll and dispatch IPC 90 pcmk_ipc_dispatch_sync, //!< Sending a command will wait for any reply 91 }; 92 93 //! Client connection to Pacemaker IPC 94 typedef struct pcmk_ipc_api_s pcmk_ipc_api_t; 95 96 /*! 97 * \brief Callback function type for Pacemaker daemon IPC APIs 98 * 99 * \param[in] api IPC API connection 100 * \param[in] event_type The type of event that occurred 101 * \param[in] status Event status 102 * \param[in] event_data Event-specific data 103 * \param[in] user_data Caller data provided when callback was registered 104 * 105 * \note For connection and disconnection events, event_data may be NULL (for 106 * local IPC) or the name of the connected node (for remote IPC, for 107 * daemons that support that). For reply and notify events, event_data is 108 * defined by the specific daemon API. 109 */ 110 typedef void (*pcmk_ipc_callback_t)(pcmk_ipc_api_t *api, 111 enum pcmk_ipc_event event_type, 112 crm_exit_t status, 113 void *event_data, void *user_data); 114 115 int pcmk_new_ipc_api(pcmk_ipc_api_t **api, enum pcmk_ipc_server server); 116 117 void pcmk_free_ipc_api(pcmk_ipc_api_t *api); 118 119 int pcmk_connect_ipc(pcmk_ipc_api_t *api, enum pcmk_ipc_dispatch dispatch_type); 120 121 void pcmk_disconnect_ipc(pcmk_ipc_api_t *api); 122 123 int pcmk_poll_ipc(pcmk_ipc_api_t *api, int timeout_ms); 124 125 void pcmk_dispatch_ipc(pcmk_ipc_api_t *api); 126 127 void pcmk_register_ipc_callback(pcmk_ipc_api_t *api, pcmk_ipc_callback_t cb, 128 void *user_data); 129 130 const char *pcmk_ipc_name(pcmk_ipc_api_t *api, bool for_log); 131 132 bool pcmk_ipc_is_connected(pcmk_ipc_api_t *api); 133 134 int pcmk_ipc_purge_node(pcmk_ipc_api_t *api, const char *node_name, 135 uint32_t nodeid); 136 137 138 /* 139 * Generic IPC API (to eventually be deprecated as public API and made internal) 140 */ 141 142 /* *INDENT-OFF* */ 143 enum crm_ipc_flags 144 { 145 crm_ipc_flags_none = 0x00000000, 146 147 crm_ipc_compressed = 0x00000001, /* Message has been compressed */ 148 149 crm_ipc_proxied = 0x00000100, /* _ALL_ replies to proxied connections need to be sent as events */ 150 crm_ipc_client_response = 0x00000200, /* A Response is expected in reply */ 151 152 // These are options for Pacemaker's internal use only (pcmk__ipc_send_*()) 153 crm_ipc_server_event = 0x00010000, /* Send an Event instead of a Response */ 154 crm_ipc_server_free = 0x00020000, /* Free the iovec after sending */ 155 crm_ipc_proxied_relay_response = 0x00040000, /* all replies to proxied connections are sent as events, this flag preserves whether the event should be treated as an actual event, or a response.*/ 156 157 crm_ipc_server_info = 0x00100000, /* Log failures as LOG_INFO */ 158 crm_ipc_server_error = 0x00200000, /* Log failures as LOG_ERR */ 159 }; 160 /* *INDENT-ON* */ 161 162 typedef struct crm_ipc_s crm_ipc_t; 163 164 crm_ipc_t *crm_ipc_new(const char *name, size_t max_size); 165 bool crm_ipc_connect(crm_ipc_t * client); 166 void crm_ipc_close(crm_ipc_t * client); 167 void crm_ipc_destroy(crm_ipc_t * client); 168 void pcmk_free_ipc_event(struct iovec *event); 169 170 int crm_ipc_send(crm_ipc_t * client, xmlNode * message, enum crm_ipc_flags flags, 171 int32_t ms_timeout, xmlNode ** reply); 172 173 int crm_ipc_get_fd(crm_ipc_t * client); 174 bool crm_ipc_connected(crm_ipc_t * client); 175 int crm_ipc_ready(crm_ipc_t * client); 176 long crm_ipc_read(crm_ipc_t * client); 177 const char *crm_ipc_buffer(crm_ipc_t * client); 178 uint32_t crm_ipc_buffer_flags(crm_ipc_t * client); 179 const char *crm_ipc_name(crm_ipc_t * client); 180 unsigned int crm_ipc_default_buffer_size(void); 181 182 /*! 183 * \brief Check the authenticity of the IPC socket peer process (legacy) 184 * 185 * If everything goes well, peer's authenticity is verified by the means 186 * of comparing against provided referential UID and GID (either satisfies), 187 * and the result of this check can be deduced from the return value. 188 * As an exception, detected UID of 0 ("root") satisfies arbitrary 189 * provided referential daemon's credentials. 190 * 191 * \param[in] sock IPC related, connected Unix socket to check peer of 192 * \param[in] refuid referential UID to check against 193 * \param[in] refgid referential GID to check against 194 * \param[out] gotpid to optionally store obtained PID of the peer 195 * (not available on FreeBSD, special value of 1 196 * used instead, and the caller is required to 197 * special case this value respectively) 198 * \param[out] gotuid to optionally store obtained UID of the peer 199 * \param[out] gotgid to optionally store obtained GID of the peer 200 * 201 * \return 0 if IPC related socket's peer is not authentic given the 202 * referential credentials (see above), 1 if it is, 203 * negative value on error (generally expressing -errno unless 204 * it was zero even on nonhappy path, -pcmk_err_generic is 205 * returned then; no message is directly emitted) 206 * 207 * \note While this function is tolerant on what constitutes authorized 208 * IPC daemon process (its effective user matches UID=0 or \p refuid, 209 * or at least its group matches \p refgid), either or both (in case 210 * of UID=0) mismatches on the expected credentials of such peer 211 * process \e shall be investigated at the caller when value of 1 212 * gets returned there, since higher-than-expected privileges in 213 * respect to the expected/intended credentials possibly violate 214 * the least privilege principle and may pose an additional risk 215 * (i.e. such accidental inconsistency shall be eventually fixed). 216 */ 217 int crm_ipc_is_authentic_process(int sock, uid_t refuid, gid_t refgid, 218 pid_t *gotpid, uid_t *gotuid, gid_t *gotgid); 219 220 /* This is controller-specific but is declared in this header for C API 221 * backward compatibility. 222 */ 223 xmlNode *create_hello_message(const char *uuid, const char *client_name, 224 const char *major_version, const char *minor_version); 225 226 #ifdef __cplusplus 227 } 228 #endif 229 230 #endif