X-Git-Url: https://git.tokkee.org/?p=sysdb.git;a=blobdiff_plain;f=src%2Ffrontend%2Fconnection.c;h=1d8b8b34d2c9ff06eeca3f0aff9584443528540c;hp=636396a2434c1edca22edfdb9b3b2103036499cc;hb=5e20183e0a2264e0aed972ceff913374ab970248;hpb=ddb933096618a6bceded29e4dc2b37cb72134366

diff --git a/src/frontend/connection.c b/src/frontend/connection.c
index 636396a..1d8b8b3 100644
--- a/src/frontend/connection.c
+++ b/src/frontend/connection.c
@@ -27,6 +27,7 @@
 
 #include "sysdb.h"
 #include "core/object.h"
+#include "core/plugin.h"
 #include "frontend/connection-private.h"
 #include "utils/error.h"
 #include "utils/strbuf.h"
@@ -38,10 +39,20 @@
 #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 */
@@ -103,8 +114,9 @@ connection_init(sdb_object_t *obj, va_list ap)
 	sdb_log(SDB_LOG_DEBUG, "frontend: Accepted connection on fd=%i",
 			conn->fd);
 
-	conn->cmd = CONNECTION_IDLE;
+	conn->cmd = SDB_CONNECTION_IDLE;
 	conn->cmd_len = 0;
+	conn->skip_len = 0;
 
 	/* update the object name */
 	snprintf(obj->name + strlen(CONN_FD_PREFIX),
@@ -121,6 +133,8 @@ connection_destroy(sdb_object_t *obj)
 	assert(obj);
 	conn = CONN(obj);
 
+	conn->ready = 0;
+
 	if (conn->buf) {
 		len = sdb_strbuf_len(conn->buf);
 		if (len)
@@ -128,11 +142,15 @@ 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);
@@ -145,68 +163,126 @@ 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
  */
 
-static uint32_t
-connection_get_int32(sdb_conn_t *conn, size_t offset)
+/*
+ * 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)
 {
-	const char *data;
-	uint32_t n;
+	uint32_t len = (uint32_t)sizeof(uint32_t) + (uint32_t)strlen(msg);
+	uint32_t p = htonl((uint32_t)prio);
+	char tmp[len + 1];
 
-	assert(conn && (sdb_strbuf_len(conn->buf) >= offset + sizeof(uint32_t)));
+	sdb_conn_t *conn;
 
-	data = sdb_strbuf_string(conn->buf);
-	memcpy(&n, data + offset, sizeof(n));
-	n = ntohl(n);
-	return n;
-} /* connection_get_int32 */
+	conn = sdb_conn_get_ctx();
+	/* no connection associated to this thread
+	 * or startup not done yet => don't leak any information */
+	if ((! conn) || (! conn->ready))
+		return 0;
+
+	/* XXX: make the log-level configurable by the client at runtime */
+	if (prio >= SDB_LOG_DEBUG)
+		return 0;
+
+	memcpy(tmp, &p, sizeof(p));
+	strcpy(tmp + sizeof(p), msg);
+
+	if (sdb_connection_send(conn, SDB_CONNECTION_LOG, len, tmp) < 0)
+		return -1;
+	return 0;
+} /* connection_log */
 
 static int
 command_handle(sdb_conn_t *conn)
 {
 	int status = -1;
 
-	assert(conn && (conn->cmd != CONNECTION_IDLE));
+	assert(conn && (conn->cmd != SDB_CONNECTION_IDLE));
+	assert(! conn->skip_len);
 
 	sdb_log(SDB_LOG_DEBUG, "frontend: Handling command %u (len: %u)",
 			conn->cmd, conn->cmd_len);
 
-	/* reset */
-	sdb_strbuf_sprintf(conn->errbuf, "");
-
-	switch (conn->cmd) {
-		case CONNECTION_PING:
-			status = sdb_connection_ping(conn);
-			break;
-		case CONNECTION_STARTUP:
-			status = sdb_fe_session_start(conn);
-			break;
-
-		case CONNECTION_LIST:
-			status = sdb_fe_list(conn);
-			break;
-
-		default:
-		{
-			sdb_log(SDB_LOG_WARNING, "frontend: Ignoring invalid command");
-			sdb_strbuf_sprintf(conn->errbuf, "Invalid command %#x", conn->cmd);
-			status = -1;
-			break;
-		}
+	if (conn->cmd == SDB_CONNECTION_PING)
+		status = sdb_connection_ping(conn);
+	else if (conn->cmd == SDB_CONNECTION_STARTUP)
+		status = sdb_fe_session_start(conn);
+	else if (conn->cmd == SDB_CONNECTION_QUERY)
+		status = sdb_fe_query(conn);
+	else if (conn->cmd == SDB_CONNECTION_FETCH)
+		status = sdb_fe_fetch(conn);
+	else if (conn->cmd == SDB_CONNECTION_LIST)
+		status = sdb_fe_list(conn);
+	else if (conn->cmd == SDB_CONNECTION_LOOKUP)
+		status = sdb_fe_lookup(conn);
+	else {
+		sdb_log(SDB_LOG_WARNING, "frontend: Ignoring invalid command %#x",
+				conn->cmd);
+		sdb_strbuf_sprintf(conn->errbuf, "Invalid command %#x", conn->cmd);
+		status = -1;
 	}
 
-	if (status)
-		sdb_connection_send(conn, CONNECTION_ERROR,
+	if (status) {
+		if (! sdb_strbuf_len(conn->errbuf))
+			sdb_strbuf_sprintf(conn->errbuf, "Failed to execute command");
+		sdb_connection_send(conn, SDB_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 */
 
@@ -214,17 +290,42 @@ 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 == SDB_CONNECTION_IDLE) && (! conn->cmd_len));
+
+	if (conn->skip_len)
+		return -1;
+
+	/* reset */
+	sdb_strbuf_clear(conn->errbuf);
+
+	conn->cmd = sdb_proto_get_int(conn->buf, 0);
+	conn->cmd_len = sdb_proto_get_int(conn->buf, sizeof(uint32_t));
+
+	sdb_strbuf_skip(conn->buf, 0, 2 * sizeof(uint32_t));
 
-	assert(conn && (conn->cmd == CONNECTION_IDLE) && (! conn->cmd_len));
+	if ((! conn->ready) && (conn->cmd != SDB_CONNECTION_STARTUP))
+		errmsg = "Authentication required";
+	else if (conn->cmd == SDB_CONNECTION_IDLE)
+		errmsg = "Invalid command 0";
 
-	conn->cmd = connection_get_int32(conn, 0);
-	conn->cmd_len = connection_get_int32(conn, sizeof(uint32_t));
+	if (errmsg) {
+		size_t len = sdb_strbuf_len(conn->buf);
 
-	len = 2 * sizeof(uint32_t);
-	if (conn->cmd == CONNECTION_IDLE)
-		len += conn->cmd_len;
-	sdb_strbuf_skip(conn->buf, 0, len);
+		sdb_strbuf_sprintf(conn->errbuf, "%s", errmsg);
+		sdb_connection_send(conn, SDB_CONNECTION_ERROR,
+				(uint32_t)strlen(errmsg), errmsg);
+		conn->skip_len += conn->cmd_len;
+		conn->cmd = SDB_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 */
 
@@ -234,6 +335,9 @@ connection_read(sdb_conn_t *conn)
 {
 	ssize_t n = 0;
 
+	if ((! conn) || (conn->fd < 0))
+		return -1;
+
 	while (42) {
 		ssize_t status;
 
@@ -242,12 +346,27 @@ 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;
@@ -257,6 +376,13 @@ 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)
 {
@@ -272,6 +398,14 @@ 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 */
 
@@ -280,21 +414,32 @@ sdb_connection_read(sdb_conn_t *conn)
 {
 	ssize_t n = 0;
 
+	sdb_conn_set_ctx(conn);
+
 	while (42) {
 		ssize_t status = connection_read(conn);
 
-		if ((conn->cmd == CONNECTION_IDLE) && (! conn->cmd_len)
+		if ((conn->cmd == SDB_CONNECTION_IDLE) && (! conn->cmd_len)
 				&& (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))
+		if ((conn->cmd != SDB_CONNECTION_IDLE)
+				&& (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 = SDB_CONNECTION_IDLE;
+			conn->cmd_len = 0;
+		}
+
 		if (status <= 0)
 			break;
 
 		n += status;
 	}
+
+	sdb_conn_set_ctx(NULL);
 	return n;
 } /* sdb_connection_read */
 
@@ -311,6 +456,12 @@ 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;
+		conn->ready = 0;
+
 		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)));
@@ -321,11 +472,11 @@ sdb_connection_send(sdb_conn_t *conn, uint32_t code,
 int
 sdb_connection_ping(sdb_conn_t *conn)
 {
-	if ((! conn) || (conn->cmd != CONNECTION_PING))
+	if ((! conn) || (conn->cmd != SDB_CONNECTION_PING))
 		return -1;
 
 	/* we're alive */
-	sdb_connection_send(conn, CONNECTION_OK, 0, NULL);
+	sdb_connection_send(conn, SDB_CONNECTION_OK, 0, NULL);
 	return 0;
 } /* sdb_connection_ping */