Reduce some rcon duplication by using a common function

4 files changed, 62 insertions, 53 deletions

diff --git a/minecctl/rcon-commands.c b/minecctl/rcon-commands.c
index dfe8647..be18bba 100644
--- a/minecctl/rcon-commands.c
+++ b/minecctl/rcon-commands.c
@@ -69,10 +69,11 @@ static void read_packet(int sfd, char *buf, size_t len, int32_t *id,
 }
 
 static void send_msg(int sfd, char *buf, size_t len, enum rcon_packet_type type,
-		     const char *msg, enum rcon_packet_type *rtype,
+		     const char *msg, int32_t *rtype,
 		     const char **reply)
 {
 	static uint32_t rcon_packet_id = 1;
+	const char *error;
 	size_t plen;
 	int32_t id;
 
@@ -84,25 +85,17 @@ static void send_msg(int sfd, char *buf, size_t len, enum rcon_packet_type type,
 
 	read_packet(sfd, buf, len, &id, rtype, reply);
 
-	/* FIXME: this should be shared */
-	if (type == RCON_PACKET_LOGIN) {
-		if (*rtype != RCON_PACKET_LOGIN_OK)
-			die("Invalid reply id");
-
-		if (id == RCON_PACKET_LOGIN_FAIL)
-			*rtype = RCON_PACKET_LOGIN_FAIL;
-		else if (id != rcon_packet_id)
-			die("Invalid reply id");
-	} else {
-		if (id != rcon_packet_id)
-			die("Invalid reply");
-	}
+	/* FIXME: Shouldn't die */
+	if (!rcon_protocol_verify_response(rcon_packet_id, id, type,
+					   *rtype, &error))
+		die("Invalid response: %s", error);
 
 	rcon_packet_id++;
 }
 
 static int rcon_login(struct cfg *cfg, struct server *server)
 {
+	const char *error;
 	char buf[4096];
 	int32_t rtype;
 	const char *reply;
@@ -135,15 +128,12 @@ static int rcon_login(struct cfg *cfg, struct server *server)
 	explicit_bzero(buf, sizeof(buf));
 	free_password(&server->scfg.rcon_password);
 
-	if (rtype == RCON_PACKET_LOGIN_OK)
-		verbose("%s: login ok", server->name);
-	else if (rtype == RCON_PACKET_LOGIN_FAIL) {
-		info("%s: login failure, invalid password?", server->name);
+	if (!rcon_protocol_verify_response(1, 1, RCON_PACKET_LOGIN,
+					   rtype, &error)) {
+		error("%s: invalid response - %s", server->name, error);
 		goto error;
-	} else {
-		error("%s: invalid return code: %" PRIi32, server->name, rtype);
-		goto error;
-	}
+	} else
+		verbose("%s: login ok", server->name);
 
 	return fd;
 
diff --git a/minecproxy/server-rcon.c b/minecproxy/server-rcon.c
index 1f3acfa..4c9da48 100644
--- a/minecproxy/server-rcon.c
+++ b/minecproxy/server-rcon.c
@@ -55,7 +55,7 @@ static void rcon_stop_reply(struct uring_task *task, int res)
 	struct server *server = container_of(task, struct server, rcon_task);
 	int32_t id;
 	int32_t type;
-	const char *msg;
+	const char *msg, *error;
 
 	assert_return(task);
 	assert_task_alive(DBG_RCON, task);
@@ -63,19 +63,13 @@ static void rcon_stop_reply(struct uring_task *task, int res)
 	if (!rcon_check_reply(task, res, &id, &type, &msg))
 		return;
 
-	if (id != 2) {
-		error("rcon(%s): stop cmd failed, reply id (%" PRIi32 ")",
-		      server->name, id);
-		goto out;
-	} else if (type != RCON_PACKET_RESPONSE) {
-		error("rcon(%s): stop cmd failed, reply type (%" PRIi32 ")",
-		      server->name, type);
-		goto out;
-	}
-
-	verbose("rcon(%s): stop command sent, reply: %s", server->name, msg);
+	if (!rcon_protocol_verify_response(2, id, RCON_PACKET_COMMAND, type,
+					   &error))
+		error("rcon(%s): stop cmd failed - %s", server->name, error);
+	else
+		verbose("rcon(%s): stop command sent, reply: %s",
+			server->name, msg);
 
-out:
 	uring_task_close_fd(task);
 }
 
@@ -102,7 +96,7 @@ static void rcon_login_reply(struct uring_task *task, int res)
 	struct server *server = container_of(task, struct server, rcon_task);
 	int32_t id;
 	int32_t type;
-	const char *msg;
+	const char *msg, *error;
 
 	assert_return(task);
 	assert_task_alive(DBG_RCON, task);
@@ -110,17 +104,9 @@ static void rcon_login_reply(struct uring_task *task, int res)
 	if (!rcon_check_reply(task, res, &id, &type, &msg))
 		return;
 
-	if (id != 1) {
-		error("rcon(%s): login failed, reply id (%" PRIi32 ")",
-		      server->name, id);
-		goto error;
-	} else if (type == RCON_PACKET_LOGIN_FAIL) {
-		error("rcon(%s): login failed, incorrect password",
-		      server->name);
-		goto error;
-	} else if (type != RCON_PACKET_LOGIN_OK) {
-		error("rcon(%s): login failed, reply type (%" PRIi32 ")",
-		      server->name, type);
+	if (!rcon_protocol_verify_response(1, id, RCON_PACKET_LOGIN, type,
+					   &error)) {
+		error("rcon(%s): login failed - %s", server->name, error);
 		goto error;
 	}
 
diff --git a/shared/rcon-protocol.c b/shared/rcon-protocol.c
index 0cf73fc..1941662 100644
--- a/shared/rcon-protocol.c
+++ b/shared/rcon-protocol.c
@@ -75,6 +75,35 @@ static void write_end(char **pos, size_t *len)
 		*len += RCON_END_LEN;
 }
 
+bool rcon_protocol_verify_response(int32_t id_sent, int32_t id_recv,
+				   enum rcon_packet_type t_sent,
+				   enum rcon_packet_type t_recv,
+				   const char **error)
+{
+	if (t_sent == RCON_PACKET_LOGIN) {
+		if (t_recv != RCON_PACKET_LOGIN_RESPONSE) {
+			*error = "invalid reply id";
+			return false;
+		} else if (id_recv == RCON_PACKET_LOGIN_FAIL_ID) {
+			*error = "login failure";
+			return false;
+		} else if (id_recv != id_sent) {
+			*error = "invalid reply id";
+			return false;
+		}
+	} else {
+		if (t_recv != RCON_PACKET_RESPONSE) {
+			*error = "invalid reply type";
+			return false;
+		} else if (id_recv != id_sent) {
+			*error = "invalid reply id";
+			return false;
+		}
+	}
+
+	return true;
+}
+
 bool rcon_protocol_create_packet(char *buf, size_t len, size_t *rlen,
 				 int32_t reqid, enum rcon_packet_type type,
 				 const char *msg)
diff --git a/shared/rcon-protocol.h b/shared/rcon-protocol.h
index b3aea98..593a43f 100644
--- a/shared/rcon-protocol.h
+++ b/shared/rcon-protocol.h
@@ -4,14 +4,13 @@
 #include <stdbool.h>
 #include <stdint.h>
 
-/* FIXME: FAIL is an id, not type, LOGIN_OK should be LOGIN_RESPONSE */
 /* clang-format off */
+#define RCON_PACKET_LOGIN_FAIL_ID   -1
 enum rcon_packet_type {
-	RCON_PACKET_LOGIN	= 3,
-	RCON_PACKET_LOGIN_OK	= 2,
-	RCON_PACKET_LOGIN_FAIL	= -1,
-	RCON_PACKET_COMMAND	= 2,
-	RCON_PACKET_RESPONSE	= 0,
+	RCON_PACKET_LOGIN	   = 3,
+	RCON_PACKET_LOGIN_RESPONSE = 2,
+	RCON_PACKET_COMMAND	   = 2,
+	RCON_PACKET_RESPONSE	   = 0,
 };
 /* clang-format on */
 
@@ -30,6 +29,11 @@ static inline size_t rcon_protocol_packet_len(size_t msglen)
 	return (RCON_PKT_MIN_LEN + msglen);
 }
 
+bool rcon_protocol_verify_response(int32_t id_sent, int32_t id_recv,
+				   enum rcon_packet_type t_sent,
+				   enum rcon_packet_type t_recv,
+				   const char **error);
+
 bool rcon_protocol_create_packet(char *buf, size_t len, size_t *rlen,
 				 int32_t reqid, enum rcon_packet_type type,
 				 const char *msg);