Code

frontend: Force-close the connection in sdb_connection_close().
[sysdb.git] / src / frontend / connection.c
index 962cd9cf8d9a14f9a3bc2f2a864e993958eb467d..93829ab248dc3992eca7124b1c6a8f95bd035345 100644 (file)
  */
 
 #include "sysdb.h"
-#include "core/error.h"
 #include "core/object.h"
+#include "core/plugin.h"
 #include "frontend/connection-private.h"
+#include "frontend/parser.h"
+#include "utils/error.h"
 #include "utils/strbuf.h"
+#include "utils/proto.h"
 
 #include <assert.h>
 #include <errno.h>
 #include <arpa/inet.h>
 #include <fcntl.h>
 
+#include <stdlib.h>
 #include <string.h>
 
+#include <pthread.h>
+
+/*
+ * private variables
+ */
+
+static pthread_key_t conn_ctx_key;
+static _Bool         conn_ctx_key_initialized = 0;
+
 /*
- * private data types
+ * private types
  */
 
 /* name of connection objects */
@@ -127,9 +140,9 @@ connection_destroy(sdb_object_t *obj)
                                        "(%zu byte%s left in buffer)", len, len == 1 ? "" : "s");
        }
 
-       sdb_log(SDB_LOG_DEBUG, "frontend: Closing connection on fd=%i",
-                       conn->fd);
-       close(conn->fd);
+       sdb_log(SDB_LOG_DEBUG, "frontend: Closing connection %s", obj->name);
+       if (conn->fd >= 0)
+               close(conn->fd);
        conn->fd = -1;
 
        sdb_strbuf_destroy(conn->buf);
@@ -144,10 +157,84 @@ static sdb_type_t connection_type = {
        /* destroy = */ connection_destroy,
 };
 
+/*
+ * private helper functions
+ */
+
+static void
+sdb_conn_ctx_destructor(void *c)
+{
+       sdb_object_t *conn = c;
+
+       if (! conn)
+               return;
+       sdb_object_deref(conn);
+} /* sdb_conn_ctx_destructor */
+
+static void
+sdb_conn_ctx_init(void)
+{
+       if (conn_ctx_key_initialized)
+               return;
+
+       pthread_key_create(&conn_ctx_key, sdb_conn_ctx_destructor);
+       conn_ctx_key_initialized = 1;
+} /* sdb_conn_ctx_init */
+
+static void
+sdb_conn_set_ctx(sdb_conn_t *conn)
+{
+       sdb_conn_t *old;
+
+       sdb_conn_ctx_init();
+
+       old = pthread_getspecific(conn_ctx_key);
+       if (old)
+               sdb_object_deref(SDB_OBJ(old));
+       if (conn)
+               sdb_object_ref(SDB_OBJ(conn));
+       pthread_setspecific(conn_ctx_key, conn);
+} /* sdb_conn_set_ctx */
+
+static sdb_conn_t *
+sdb_conn_get_ctx(void)
+{
+       if (! conn_ctx_key_initialized)
+               return NULL;
+       return pthread_getspecific(conn_ctx_key);
+} /* sdb_conn_get_ctx */
+
 /*
  * connection handler functions
  */
 
+/*
+ * connection_log:
+ * Send a log message originating from the current thread to the client.
+ */
+static int
+connection_log(int prio, const char *msg,
+               sdb_object_t __attribute__((unused)) *user_data)
+{
+       sdb_conn_t *conn;
+
+       conn = sdb_conn_get_ctx();
+       /* no connection associated to this thread
+        * or user not authenticated yet => don't leak any information */
+       if ((! conn) || (! conn->username))
+               return 0;
+
+       /* XXX: make the log-level configurable by the client at runtime */
+       if (prio >= SDB_LOG_DEBUG)
+               return 0;
+
+       /* TODO: Use CONNECTION_LOG_<prio>? */
+       if (sdb_connection_send(conn, CONNECTION_LOG,
+                               (uint32_t)strlen(msg), msg) < 0)
+               return -1;
+       return 0;
+} /* connection_log */
+
 static uint32_t
 connection_get_int32(sdb_conn_t *conn, size_t offset)
 {
@@ -172,6 +259,13 @@ command_handle(sdb_conn_t *conn)
        sdb_log(SDB_LOG_DEBUG, "frontend: Handling command %u (len: %u)",
                        conn->cmd, conn->cmd_len);
 
+       if ((! conn->username) && (conn->cmd != CONNECTION_STARTUP)) {
+               const char *errmsg = "Authentication required";
+               sdb_connection_send(conn, CONNECTION_ERROR,
+                               (uint32_t)strlen(errmsg), errmsg);
+               return -1;
+       }
+
        /* reset */
        sdb_strbuf_sprintf(conn->errbuf, "");
 
@@ -183,13 +277,74 @@ command_handle(sdb_conn_t *conn)
                        status = sdb_fe_session_start(conn);
                        break;
 
+               case CONNECTION_QUERY:
+               {
+                       sdb_llist_t *parsetree;
+                       sdb_conn_node_t *node = NULL;
+
+                       parsetree = sdb_fe_parse(sdb_strbuf_string(conn->buf),
+                                       (int)conn->cmd_len);
+                       if (! parsetree) {
+                               sdb_log(SDB_LOG_ERR, "frontend: Failed to parse query '%s'",
+                                               sdb_strbuf_string(conn->buf));
+                               status = -1;
+                               break;
+                       }
+
+                       switch (sdb_llist_len(parsetree)) {
+                               case 0:
+                                       /* skipping empty command */
+                                       break;
+                               case 1:
+                                       node = SDB_CONN_NODE(sdb_llist_get(parsetree, 0));
+                                       break;
+
+                               default:
+                                       sdb_log(SDB_LOG_WARNING, "frontend: Ignoring %d command%s "
+                                                       "in multi-statement query '%s'",
+                                                       sdb_llist_len(parsetree) - 1,
+                                                       sdb_llist_len(parsetree) == 2 ? "" : "s",
+                                                       sdb_strbuf_string(conn->buf));
+                                       node = SDB_CONN_NODE(sdb_llist_get(parsetree, 0));
+                       }
+
+                       if (node) {
+                               status = sdb_fe_exec(conn, node);
+                               sdb_object_deref(SDB_OBJ(node));
+                       }
+
+                       sdb_llist_destroy(parsetree);
+                       break;
+               }
+
+               case CONNECTION_FETCH:
+                       status = sdb_fe_fetch(conn, sdb_strbuf_string(conn->buf));
+                       break;
                case CONNECTION_LIST:
                        status = sdb_fe_list(conn);
                        break;
+               case CONNECTION_LOOKUP:
+               {
+                       sdb_store_matcher_t *m;
+
+                       m = sdb_fe_parse_matcher(sdb_strbuf_string(conn->buf),
+                                       (int)conn->cmd_len);
+                       if (! m) {
+                               sdb_log(SDB_LOG_ERR, "frontend: Failed to parse expression '%s'",
+                                               sdb_strbuf_string(conn->buf));
+                               status = -1;
+                               break;
+                       }
+
+                       status = sdb_fe_lookup(conn, m);
+                       sdb_object_deref(SDB_OBJ(m));
+                       break;
+               }
 
                default:
                {
-                       sdb_log(SDB_LOG_WARNING, "frontend: Ignoring invalid command");
+                       sdb_log(SDB_LOG_WARNING, "frontend: Ignoring invalid command %#x",
+                                       conn->cmd);
                        sdb_strbuf_sprintf(conn->errbuf, "Invalid command %#x", conn->cmd);
                        status = -1;
                        break;
@@ -203,7 +358,7 @@ command_handle(sdb_conn_t *conn)
 
        /* remove the command from the buffer */
        if (conn->cmd_len)
-               sdb_strbuf_skip(conn->buf, conn->cmd_len);
+               sdb_strbuf_skip(conn->buf, 0, conn->cmd_len);
        conn->cmd = CONNECTION_IDLE;
        conn->cmd_len = 0;
        return status;
@@ -223,7 +378,7 @@ command_init(sdb_conn_t *conn)
        len = 2 * sizeof(uint32_t);
        if (conn->cmd == CONNECTION_IDLE)
                len += conn->cmd_len;
-       sdb_strbuf_skip(conn->buf, len);
+       sdb_strbuf_skip(conn->buf, 0, len);
        return 0;
 } /* command_init */
 
@@ -233,6 +388,9 @@ connection_read(sdb_conn_t *conn)
 {
        ssize_t n = 0;
 
+       if ((! conn) || (conn->fd < 0))
+               return -1;
+
        while (42) {
                ssize_t status;
 
@@ -241,6 +399,9 @@ connection_read(sdb_conn_t *conn)
                if (status < 0) {
                        if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
                                break;
+
+                       close(conn->fd);
+                       conn->fd = -1;
                        return (int)status;
                }
                else if (! status) /* EOF */
@@ -256,6 +417,13 @@ connection_read(sdb_conn_t *conn)
  * public API
  */
 
+int
+sdb_connection_enable_logging(void)
+{
+       return sdb_plugin_register_log("connection-logger", connection_log,
+                       /* user_data = */ NULL);
+} /* sdb_connection_enable_logging */
+
 sdb_conn_t *
 sdb_connection_accept(int fd)
 {
@@ -271,6 +439,14 @@ sdb_connection_accept(int fd)
 void
 sdb_connection_close(sdb_conn_t *conn)
 {
+       if (! conn)
+               return;
+
+       /* close the connection even if someone else still references it */
+       if (conn->fd >= 0)
+               close(conn->fd);
+       conn->fd = -1;
+
        sdb_object_deref(SDB_OBJ(conn));
 } /* sdb_connection_close */
 
@@ -279,6 +455,8 @@ sdb_connection_read(sdb_conn_t *conn)
 {
        ssize_t n = 0;
 
+       sdb_conn_set_ctx(conn);
+
        while (42) {
                ssize_t status = connection_read(conn);
 
@@ -294,6 +472,8 @@ sdb_connection_read(sdb_conn_t *conn)
 
                n += status;
        }
+
+       sdb_conn_set_ctx(NULL);
        return n;
 } /* sdb_connection_read */
 
@@ -301,50 +481,25 @@ ssize_t
 sdb_connection_send(sdb_conn_t *conn, uint32_t code,
                uint32_t msg_len, const char *msg)
 {
-       size_t len = 2 * sizeof(uint32_t) + msg_len;
-       char buffer[len];
-       char *buf;
-
-       uint32_t tmp;
+       ssize_t status;
 
        if ((! conn) || (conn->fd < 0))
                return -1;
 
-       tmp = htonl(code);
-       memcpy(buffer, &tmp, sizeof(uint32_t));
-
-       tmp = htonl(msg_len);
-       memcpy(buffer + sizeof(uint32_t), &tmp, sizeof(uint32_t));
-
-       if (msg_len)
-               memcpy(buffer + 2 * sizeof(uint32_t), msg, msg_len);
+       status = sdb_proto_send_msg(conn->fd, code, msg_len, msg);
+       if (status < 0) {
+               char errbuf[1024];
 
-       buf = buffer;
-       while (len > 0) {
-               ssize_t status;
-
-               /* XXX: use select() */
-
-               errno = 0;
-               status = write(conn->fd, buf, len);
-               if (status < 0) {
-                       char errbuf[1024];
+               /* tell other code that there was a problem and, more importantly,
+                * make sure we don't try to send further logs to the connection */
+               close(conn->fd);
+               conn->fd = -1;
 
-                       if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
-                               continue;
-                       if (errno == EINTR)
-                               continue;
-
-                       sdb_log(SDB_LOG_ERR, "frontend: Failed to send msg "
-                                       "(code: %u, len: %u) to client: %s", code, msg_len,
-                                       sdb_strerror(errno, errbuf, sizeof(errbuf)));
-                       return status;
-               }
-
-               len -= (size_t)status;
-               buf += status;
+               sdb_log(SDB_LOG_ERR, "frontend: Failed to send msg "
+                               "(code: %u, len: %u) to client: %s", code, msg_len,
+                               sdb_strerror(errno, errbuf, sizeof(errbuf)));
        }
-       return (ssize_t)len;
+       return status;
 } /* sdb_connection_send */
 
 int