X-Git-Url: https://git.tokkee.org/?p=sysdb.git;a=blobdiff_plain;f=src%2Ffrontend%2Fconnection.c;h=f35f7b39c82a8278f47137e65810163094c33044;hp=91196dcd4448125864073bff616ce24f9d406809;hb=ad77ec3d257ac66d74e91452d098882247abdc0a;hpb=7dbab14d8d2113e0160a9c372b40be1ca8eea2d1

diff --git a/src/frontend/connection.c b/src/frontend/connection.c
index 91196dc..f35f7b3 100644
--- a/src/frontend/connection.c
+++ b/src/frontend/connection.c
@@ -25,6 +25,10 @@
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#ifdef HAVE_CONFIG_H
+#	include "config.h"
+#endif
+
 #include "sysdb.h"
 #include "core/object.h"
 #include "core/plugin.h"
@@ -32,6 +36,7 @@
 #include "utils/error.h"
 #include "utils/strbuf.h"
 #include "utils/proto.h"
+#include "utils/os.h"
 
 #include <assert.h>
 #include <errno.h>
@@ -42,6 +47,19 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/param.h>
+
+#ifdef HAVE_UCRED_H
+#	include <ucred.h>
+#endif
+#ifdef HAVE_SYS_UCRED_H
+#	include <sys/ucred.h>
+#endif
+
+#include <pwd.h>
+
 #include <pthread.h>
 
 /*
@@ -49,7 +67,7 @@
  */
 
 static pthread_key_t conn_ctx_key;
-static _Bool         conn_ctx_key_initialized = 0;
+static bool          conn_ctx_key_initialized = 0;
 
 /*
  * private types
@@ -59,6 +77,48 @@ static _Bool         conn_ctx_key_initialized = 0;
 #define CONN_FD_PREFIX "conn#"
 #define CONN_FD_PLACEHOLDER "XXXXXXX"
 
+/* XXX: only supports UNIX sockets so far */
+static char *
+peer(int sockfd)
+{
+	uid_t uid;
+
+	struct passwd pw_entry;
+	struct passwd *result = NULL;
+	char buf[1024];
+
+#ifdef SO_PEERCRED
+	struct ucred cred;
+	socklen_t len = sizeof(cred);
+
+	if (getsockopt(sockfd, SOL_SOCKET, SO_PEERCRED, &cred, &len)
+			|| (len != sizeof(cred)))
+		return NULL;
+	uid = cred.uid;
+#else /* SO_PEERCRED */
+	errno = ENOSYS;
+	return NULL;
+#endif
+
+	memset(&pw_entry, 0, sizeof(pw_entry));
+	if (getpwuid_r(uid, &pw_entry, buf, sizeof(buf), &result)
+			|| (! result))
+		return NULL;
+	return strdup(result->pw_name);
+} /* peer */
+
+static ssize_t
+conn_read(sdb_conn_t *conn, size_t len)
+{
+	return sdb_strbuf_read(conn->buf, conn->fd, len);
+} /* conn_read */
+
+static ssize_t
+conn_write(sdb_conn_t *conn, const void *buf, size_t len)
+{
+	return sdb_write(conn->fd, len, buf);
+} /* conn_write */
+
 static int
 connection_init(sdb_object_t *obj, va_list ap)
 {
@@ -96,6 +156,12 @@ connection_init(sdb_object_t *obj, va_list ap)
 		return -1;
 	}
 
+	/* defaults */
+	conn->read = conn_read;
+	conn->write = conn_write;
+	conn->finish = NULL;
+	conn->session = NULL;
+
 	if (conn->client_addr.ss_family != AF_UNIX) {
 		sdb_log(SDB_LOG_ERR, "frontend: Accepted connection using "
 				"unexpected family type %d", conn->client_addr.ss_family);
@@ -111,11 +177,22 @@ connection_init(sdb_object_t *obj, va_list ap)
 		return -1;
 	}
 
+	conn->username = peer(conn->fd);
+	if (! conn->username) {
+		char buf[1024];
+		sdb_log(SDB_LOG_ERR, "frontend: Failed to retrieve peer for "
+				"connection conn#%i: %s", conn->fd,
+				sdb_strerror(errno, buf, sizeof(buf)));
+		return -1;
+	}
+	conn->ready = 0;
+
 	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),
@@ -132,6 +209,12 @@ connection_destroy(sdb_object_t *obj)
 	assert(obj);
 	conn = CONN(obj);
 
+	conn->ready = 0;
+
+	if (conn->finish)
+		conn->finish(conn);
+	conn->finish = NULL;
+
 	if (conn->buf) {
 		len = sdb_strbuf_len(conn->buf);
 		if (len)
@@ -139,10 +222,12 @@ 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);
-	conn->fd = -1;
+	sdb_log(SDB_LOG_DEBUG, "frontend: Closing connection %s", obj->name);
+	sdb_connection_close(conn);
+
+	if (conn->username)
+		free(conn->username);
+	conn->username = NULL;
 
 	sdb_strbuf_destroy(conn->buf);
 	conn->buf = NULL;
@@ -183,7 +268,13 @@ sdb_conn_ctx_init(void)
 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);
@@ -209,134 +300,69 @@ static int
 connection_log(int prio, const char *msg,
 		sdb_object_t __attribute__((unused)) *user_data)
 {
+	uint32_t len = (uint32_t)sizeof(uint32_t) + (uint32_t)strlen(msg);
+	uint32_t p = htonl((uint32_t)prio);
+	char tmp[len + 1];
+
 	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))
+	 * 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;
 
-	/* TODO: Use CONNECTION_LOG_<prio>? */
-	if (sdb_connection_send(conn, CONNECTION_LOG,
-				(uint32_t)strlen(msg), msg) < 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 uint32_t
-connection_get_int32(sdb_conn_t *conn, size_t offset)
-{
-	const char *data;
-	uint32_t n;
-
-	assert(conn && (sdb_strbuf_len(conn->buf) >= offset + sizeof(uint32_t)));
-
-	data = sdb_strbuf_string(conn->buf);
-	memcpy(&n, data + offset, sizeof(n));
-	n = ntohl(n);
-	return n;
-} /* connection_get_int32 */
-
 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);
 
-	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;
+	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 if (conn->cmd == SDB_CONNECTION_STORE)
+		status = sdb_fe_store(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;
 	}
 
-	/* 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_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;
-
-		default:
-		{
-			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;
-		}
-	}
-
-	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 */
 
@@ -344,17 +370,42 @@ 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);
 
-	assert(conn && (conn->cmd == CONNECTION_IDLE) && (! conn->cmd_len));
+	if (sdb_proto_unmarshal_header(SDB_STRBUF_STR(conn->buf),
+				&conn->cmd, &conn->cmd_len) < 0)
+		return -1;
+	sdb_strbuf_skip(conn->buf, 0, 2 * sizeof(uint32_t));
+
+	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 */
 
@@ -364,20 +415,37 @@ connection_read(sdb_conn_t *conn)
 {
 	ssize_t n = 0;
 
+	if ((! conn) || (conn->fd < 0))
+		return -1;
+
 	while (42) {
 		ssize_t status;
 
 		errno = 0;
-		status = sdb_strbuf_read(conn->buf, conn->fd, 1024);
+		status = conn->read(conn, 1024);
 		if (status < 0) {
 			if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
 				break;
+
+			sdb_connection_close(conn);
 			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;
@@ -409,11 +477,21 @@ sdb_connection_accept(int fd)
 void
 sdb_connection_close(sdb_conn_t *conn)
 {
-	sdb_object_deref(SDB_OBJ(conn));
+	if (! conn)
+		return;
+
+	if (conn->finish)
+		conn->finish(conn);
+	conn->finish = NULL;
+
+	/* close the connection even if someone else still references it */
+	if (conn->fd >= 0)
+		close(conn->fd);
+	conn->fd = -1;
 } /* sdb_connection_close */
 
 ssize_t
-sdb_connection_read(sdb_conn_t *conn)
+sdb_connection_handle(sdb_conn_t *conn)
 {
 	ssize_t n = 0;
 
@@ -422,13 +500,20 @@ sdb_connection_read(sdb_conn_t *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;
 
@@ -437,21 +522,29 @@ sdb_connection_read(sdb_conn_t *conn)
 
 	sdb_conn_set_ctx(NULL);
 	return n;
-} /* sdb_connection_read */
+} /* sdb_connection_handle */
 
 ssize_t
 sdb_connection_send(sdb_conn_t *conn, uint32_t code,
 		uint32_t msg_len, const char *msg)
 {
+	char buf[2 * sizeof(uint32_t) + msg_len];
 	ssize_t status;
 
 	if ((! conn) || (conn->fd < 0))
 		return -1;
+	if (sdb_proto_marshal(buf, sizeof(buf), code, msg_len, msg) < 0)
+		return -1;
 
-	status = sdb_proto_send_msg(conn->fd, code, msg_len, msg);
+	status = conn->write(conn, buf, sizeof(buf));
 	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 */
+		sdb_connection_close(conn);
+		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)));
@@ -462,11 +555,11 @@ 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 */