Code

plugin: Make sdb_plugin_info_t public.
[sysdb.git] / src / frontend / connection.c
index 24735de2f0e55fac5ce8f7313445068f0ce9263e..173bdef475a278d264c999194766f82bbadffe6c 100644 (file)
@@ -27,7 +27,9 @@
 
 #include "sysdb.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 <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 */
@@ -105,6 +117,7 @@ connection_init(sdb_object_t *obj, va_list ap)
 
        conn->cmd = CONNECTION_IDLE;
        conn->cmd_len = 0;
+       conn->skip_len = 0;
 
        /* update the object name */
        snprintf(obj->name + strlen(CONN_FD_PREFIX),
@@ -128,11 +141,15 @@ 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;
 
+       if (conn->username)
+               free(conn->username);
+       conn->username = NULL;
+
        sdb_strbuf_destroy(conn->buf);
        conn->buf = NULL;
        sdb_strbuf_destroy(conn->errbuf);
@@ -145,10 +162,84 @@ 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)
 {
@@ -169,20 +260,11 @@ command_handle(sdb_conn_t *conn)
        int status = -1;
 
        assert(conn && (conn->cmd != CONNECTION_IDLE));
+       assert(! conn->skip_len);
 
        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, "");
-
        switch (conn->cmd) {
                case CONNECTION_PING:
                        status = sdb_connection_ping(conn);
@@ -222,16 +304,38 @@ command_handle(sdb_conn_t *conn)
                                        node = SDB_CONN_NODE(sdb_llist_get(parsetree, 0));
                        }
 
-                       if (node)
+                       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:
                {
@@ -247,12 +351,6 @@ command_handle(sdb_conn_t *conn)
                sdb_connection_send(conn, CONNECTION_ERROR,
                                (uint32_t)sdb_strbuf_len(conn->errbuf),
                                sdb_strbuf_string(conn->errbuf));
-
-       /* remove the command from the buffer */
-       if (conn->cmd_len)
-               sdb_strbuf_skip(conn->buf, 0, conn->cmd_len);
-       conn->cmd = CONNECTION_IDLE;
-       conn->cmd_len = 0;
        return status;
 } /* command_handle */
 
@@ -260,17 +358,42 @@ command_handle(sdb_conn_t *conn)
 static int
 command_init(sdb_conn_t *conn)
 {
-       size_t len;
+       const char *errmsg = NULL;
 
        assert(conn && (conn->cmd == CONNECTION_IDLE) && (! conn->cmd_len));
 
+       if (conn->skip_len)
+               return -1;
+
+       /* reset */
+       sdb_strbuf_sprintf(conn->errbuf, "");
+
        conn->cmd = connection_get_int32(conn, 0);
        conn->cmd_len = connection_get_int32(conn, sizeof(uint32_t));
 
-       len = 2 * sizeof(uint32_t);
-       if (conn->cmd == CONNECTION_IDLE)
-               len += conn->cmd_len;
-       sdb_strbuf_skip(conn->buf, 0, len);
+       sdb_strbuf_skip(conn->buf, 0, 2 * sizeof(uint32_t));
+
+       if ((! conn->username) && (conn->cmd != CONNECTION_STARTUP))
+               errmsg = "Authentication required";
+       else if (conn->cmd == CONNECTION_IDLE)
+               errmsg = "Invalid command 0";
+
+       if (errmsg) {
+               size_t len = sdb_strbuf_len(conn->buf);
+
+               sdb_strbuf_sprintf(conn->errbuf, errmsg);
+               sdb_connection_send(conn, CONNECTION_ERROR,
+                               (uint32_t)strlen(errmsg), errmsg);
+               conn->skip_len += conn->cmd_len;
+               conn->cmd = CONNECTION_IDLE;
+               conn->cmd_len = 0;
+
+               if (len > conn->skip_len)
+                       len = conn->skip_len;
+               sdb_strbuf_skip(conn->buf, 0, len);
+               conn->skip_len -= len;
+               /* connection_read will handle anything else */
+       }
        return 0;
 } /* command_init */
 
@@ -280,6 +403,9 @@ connection_read(sdb_conn_t *conn)
 {
        ssize_t n = 0;
 
+       if ((! conn) || (conn->fd < 0))
+               return -1;
+
        while (42) {
                ssize_t status;
 
@@ -288,12 +414,27 @@ 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 */
                        break;
 
+               if (conn->skip_len) {
+                       size_t len = (size_t)status < conn->skip_len
+                               ? (size_t)status : conn->skip_len;
+                       sdb_strbuf_skip(conn->buf, 0, len);
+                       conn->skip_len -= len;
+               }
+
                n += status;
+
+               /* give the main loop a chance to execute commands (and free up buffer
+                * space) on large amounts of incoming traffic */
+               if (n > 1024 * 1024)
+                       break;
        }
 
        return n;
@@ -303,6 +444,13 @@ 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)
 {
@@ -318,6 +466,14 @@ 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 */
 
@@ -326,6 +482,8 @@ sdb_connection_read(sdb_conn_t *conn)
 {
        ssize_t n = 0;
 
+       sdb_conn_set_ctx(conn);
+
        while (42) {
                ssize_t status = connection_read(conn);
 
@@ -333,14 +491,23 @@ sdb_connection_read(sdb_conn_t *conn)
                                && (sdb_strbuf_len(conn->buf) >= 2 * sizeof(int32_t)))
                        command_init(conn);
                if ((conn->cmd != CONNECTION_IDLE)
-                               && (sdb_strbuf_len(conn->buf) >= conn->cmd_len))
+                               && (sdb_strbuf_len(conn->buf) >= conn->cmd_len)) {
                        command_handle(conn);
 
+                       /* remove the command from the buffer */
+                       if (conn->cmd_len)
+                               sdb_strbuf_skip(conn->buf, 0, conn->cmd_len);
+                       conn->cmd = CONNECTION_IDLE;
+                       conn->cmd_len = 0;
+               }
+
                if (status <= 0)
                        break;
 
                n += status;
        }
+
+       sdb_conn_set_ctx(NULL);
        return n;
 } /* sdb_connection_read */
 
@@ -357,6 +524,11 @@ sdb_connection_send(sdb_conn_t *conn, uint32_t code,
        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;
+
                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)));