Flesh out the new command a bit more

6 files changed, 341 insertions, 85 deletions

diff --git a/examples/minecserver@.service b/examples/minecserver@.service
index e14ed81..bb72c5b 100644
--- a/examples/minecserver@.service
+++ b/examples/minecserver@.service
@@ -1 +1,36 @@
-This is an example service
+[Unit]
+Description=Minecraft Server %i
+#Documentation= https://url https://url man:abc
+Wants=network-online.target
+After=network-online.target
+ConditionFileNotEmpty=%E/minecproxy/config/%i.mcserver
+ConditionPathExists=%E/minecproxy/servers/%i/eula.txt
+ConditionPathExists=%E/minecproxy/servers/%i/server.properties
+ConditionPathExists=%E/minecproxy/servers/%i/server.jar
+
+[Service]
+Type=exec
+ExecStart=/usr/bin/java -Xmx1024M -Xms1024M -jar server.jar --nogui
+ExecStop=-/usr/bin/minecctl -c %E/minecproxy/config/ -f stop %i
+# Optional: this will autogenerate new servers on the fly
+# if this is used, comment out the ConditionPathExists checks above
+#ExecStartPre=/usr/bin/minecctl new %i
+TimeoutStopSec=120
+KillSignal=SIGCONT
+Restart=on-failure
+WorkingDirectory=%E/minecproxy/servers/%i
+Nice=5
+LimitCORE=0
+NoNewPrivileges=true
+KeyringMode=private
+PrivateUsers=true
+ProtectSystem=strict
+ReadWritePaths=%E/minecproxy/servers/%i
+PrivateDevices=true
+ProtectKernelTunables=true
+ProtectControlGroups=true
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
+RestrictNamespaces=true
+LockPersonality=true
+RestrictSUIDSGID=true
+PrivateTmp=true
diff --git a/examples/server.properties b/examples/server.properties
index f992c40..dddb380 100644
--- a/examples/server.properties
+++ b/examples/server.properties
@@ -1 +1,9 @@
-This is an example server.properties file
+#Minecraft server properties
+# This is a partial file, it will be replaced with a
+# fleshed out version the first time the Minecraft
+# server is executed.
+motd=A Minecraft Server
+server-port=25565
+enable-rcon=true
+rcon.port=25575
+rcon.password=secret
diff --git a/minecctl/minecctl.c b/minecctl/minecctl.c
index 3b1da80..344d3d7 100644
--- a/minecctl/minecctl.c
+++ b/minecctl/minecctl.c
@@ -497,6 +497,12 @@ static void parse_cmdline(struct cfg *cfg, int argc, char *const *argv)
 int main(int argc, char *const *argv)
 {
 	struct cfg cfg = {
+		.listen_port_min = 20000,
+		.listen_port_max = 23999,
+		.mc_port_min = 24000,
+		.mc_port_max = 27999,
+		.rcon_port_min = 28000,
+		.rcon_port_max = 31999,
 		.servers = LIST_HEAD_INIT(cfg.servers),
 	};
 	bool success = false;
diff --git a/minecctl/minecctl.h b/minecctl/minecctl.h
index 46c616a..5778d13 100644
--- a/minecctl/minecctl.h
+++ b/minecctl/minecctl.h
@@ -12,6 +12,12 @@ struct cfg {
 	char *rcon_addrstr;
 	char *mc_addrstr;
 	char **commands;
+	uint16_t listen_port_min;
+	uint16_t listen_port_max;
+	uint16_t mc_port_min;
+	uint16_t mc_port_max;
+	uint16_t rcon_port_min;
+	uint16_t rcon_port_max;
 	bool force_stop;
 	bool default_set;
 	bool server_list_loaded;
diff --git a/minecctl/misc-commands.c b/minecctl/misc-commands.c
index 34cbedf..f3ddff2 100644
--- a/minecctl/misc-commands.c
+++ b/minecctl/misc-commands.c
@@ -7,6 +7,8 @@
 #include <fcntl.h>
 #include <string.h>
 #include <errno.h>
+#include <sys/random.h>
+#include <inttypes.h>
 
 #include "shared/utils.h"
 #include "minecctl.h"
@@ -35,10 +37,11 @@ static bool create_link(int dfd, const char *source, const char *target)
 	return true;
 }
 
-static bool write_cfg_file(int dfd, const char *name, unsigned char *content,
+static bool write_cfg_file(int dfd, const char *name,
+			   const unsigned char *content,
 			   size_t len)
 {
-	int fd;
+	_cleanup_close_ int fd;
 	ssize_t done = 0, r;
 	bool rv = true;
 
@@ -61,13 +64,12 @@ static bool write_cfg_file(int dfd, const char *name, unsigned char *content,
 		done += r;
 	}
 
-	close(fd);
 	return rv;
 }
 
 static bool find_user_service(int xfd, const char *service)
 {
-	int dfd;
+	_cleanup_close_ int dfd = -1;
 	/* FIXME: Make this a macro, make paths #defines */
 	char sub_path[STRLEN("systemd/user/") + strlen(service) + 1];
 	char etc_path[STRLEN("/etc/systemd/user/") + strlen(service) + 1];
@@ -102,10 +104,8 @@ static bool find_user_service(int xfd, const char *service)
 		if (faccessat(dfd, sub_path, R_OK, 0) == 0) {
 			info("User service %s already installed in "
 			     "$XDG_DATA_HOME/systemd/user/", service);
-			close(dfd);
 			return true;
 		}
-		close(dfd);
 	}
 
 	if (access(usr_path, R_OK) == 0) {
@@ -120,118 +120,98 @@ static bool find_user_service(int xfd, const char *service)
 static bool create_user_service(int xfd, const char *service,
 				unsigned char *content, size_t len)
 {
-	int sfd, ufd = -1;
-	bool rv = false;
+	_cleanup_close_ int sfd = -1;
+	_cleanup_close_ int ufd = -1;
 
 	if (find_user_service(xfd, service))
 		return true;
 
 	sfd = open_subdir(xfd, "systemd", true);
 	if (sfd < 0)
-		goto out;
+		return false;
 
 	ufd = open_subdir(sfd, "user", true);
 	if (ufd < 0)
-		goto out;
+		return false;
 
 	if (!write_cfg_file(ufd, service, content, len))
-		goto out;
+		return false;
 
 	info("Created user service file $XDG_CONFIG_HOME/systemd/user/%s",
 	     service);
-	rv = true;
-
-out:
-	if (ufd >= 0)
-		close(ufd);
-	if (sfd >= 0)
-		close(sfd);
-	return rv;
+	return true;
 }
 
 static bool create_server_cfg(int sfd, int cfd, const char *name,
-			      const char *filename)
+			      const char *filename,
+			      const unsigned char *properties,
+			      size_t properties_len)
 {
-	int efd = -1;
-	bool rv = false;
+	_cleanup_close_ int efd = -1;
 
 	efd = open_subdir(sfd, name, true);
 	if (efd < 0) {
 		error("Failed to create configuration directory \"%s\"", name);
-		goto out;
+		return false;
 	}
 
 	if (!write_cfg_file(efd, "eula.txt", ___examples_eula_txt,
 			    ___examples_eula_txt_len))
-		goto out;
+		return false;
 
 	if (!write_cfg_file(efd, "server.properties",
-			    ___examples_server_properties,
-			    ___examples_server_properties_len))
-		goto out;
+			    properties, properties_len))
+		return false;
 
 	if (!create_link(efd, "server.jar", "../server.jar"))
-		goto out;
+		return false;
 
 	if (!write_cfg_file(cfd, filename,
 			    ___examples_example_mcserver,
 			    ___examples_example_mcserver_len))
-		goto out;
-
-	rv = true;
-
-out:
-	if (efd >= 0)
-		close(efd);
+		return false;
 
-	return rv;
+	return true;
 }
 
 static bool create_config_tree(int xfd)
 {
-	int mfd = -1, sfd = -1, cfd = -1;
-	bool rv = false;
+	_cleanup_close_ int mfd = -1;
+	_cleanup_close_ int sfd = -1;
+	_cleanup_close_ int cfd = -1;
 
 	mfd = open_subdir(xfd, "minecproxy", true);
 	if (mfd < 0)
-		goto out;
+		return false;
 
 	sfd = open_subdir(mfd, "servers", true);
 	if (sfd < 0)
-		goto out;
+		return false;
 
 	if (!write_cfg_file(sfd, "README.TXT", ___examples_README_TXT,
 			    ___examples_README_TXT_len))
-		goto out;
+		return false;
 
 	cfd = open_subdir(mfd, "config", true);
 	if (cfd < 0)
-		goto out;
+		return false;
 
 	if (!write_cfg_file(cfd, "minecproxy.conf", ___examples_minecproxy_conf,
 			    ___examples_minecproxy_conf_len))
-		goto out;
+		return false;
 
-	if (!create_server_cfg(sfd, cfd, "example", "example.mcserver"))
-		goto out;
+	if (!create_server_cfg(sfd, cfd, "example", "example.mcserver",
+			       ___examples_server_properties,
+			       ___examples_server_properties_len))
+		return false;
 
 	info("Created configuration in $XDG_CONFIG_HOME/minecproxy");
-	rv = true;
-
-out:
-	if (mfd >= 0)
-		close(mfd);
-	if (sfd >= 0)
-		close(sfd);
-	if (cfd >= 0)
-		close(cfd);
-	return rv;
+	return true;
 }
 
 bool do_init(struct cfg *cfg)
 {
-	int xfd;
-	bool rv = false;
+	_cleanup_close_ int xfd = -1;
 
 	if (cfg->dir_path) {
 		xfd = open(cfg->dir_path, O_PATH | O_CLOEXEC | O_DIRECTORY);
@@ -241,32 +221,27 @@ bool do_init(struct cfg *cfg)
 		xfd = open_xdg_cfg_dir(true);
 
 	if (xfd < 0)
-		goto out;
+		return false;
 
 	if (!create_config_tree(xfd))
-		goto out;
+		return false;
 
 	if (cfg->dir_path) {
 		info("Option -c used, not creating systemd services");
-		rv = true;
-		goto out;
+		return true;
 	}
 
 	if (!create_user_service(xfd, "minecserver@.service",
 				 ___examples_minecserver__service,
 				 ___examples_minecserver__service_len))
-		goto out;
+		return false;
 
 	if (!create_user_service(xfd, "minecproxy.service",
 				 ___examples_minecproxy_service,
 				 ___examples_minecproxy_service_len))
-		goto out;
+		return false;
 
-	rv = true;
-out:
-	if (xfd >= 0)
-		close(xfd);
-	return rv;
+	return true;
 }
 
 static bool valid_name(const char *name)
@@ -300,12 +275,204 @@ static bool valid_name(const char *name)
 	return true;
 }
 
+/* FIXME: Share this */
+static inline char tohex(uint8_t val)
+{
+	static const char hex[] = "0123456789abcdef";
+
+	return hex[val & 0x0f];
+}
+
+static bool generate_random_password(char *buf, size_t len)
+{
+	size_t written;
+	ssize_t r;
+	const char *s;
+	char *d;
+
+	if (len < 3)
+		return false;
+
+	char rnd[(len - 1) / 2];
+
+	for (written = 0; written < sizeof(rnd); written += r) {
+		r = getrandom(rnd + written, sizeof(rnd) - written, 0);
+		if (r < 0) {
+			if (errno == EAGAIN || errno == EINTR)
+				continue;
+
+			error("getrandom failure: %m");
+			return false;
+		}
+	}
+
+	for (s = rnd, d = buf; s < (rnd + sizeof(rnd)); s++) {
+		*(d++) = tohex(*s >> 4);
+		*(d++) = tohex(*s);
+	}
+	*d = '\0';
+
+	info("Hex = %s", buf);
+	return true;
+}
+
+static unsigned char *create_mc_properties(const char *name, uint16_t mc_port,
+					   uint16_t rcon_port,
+					   const char *rcon_password,
+					   size_t *len)
+{
+	char hexrnd[16 + 1];
+	char *properties;
+	int r;
+
+	if (!rcon_password) {
+		if (!generate_random_password(hexrnd, sizeof(hexrnd))) {
+			error("Failed to generate random password");
+			return NULL;
+		}
+	}
+
+	/* FIXME: server-ip= */
+	r = asprintf(&properties,
+		     "#Minecraft server properties\n"
+		     "# This is a partial file, it will be replaced with a\n"
+		     "# fleshed out version the first time the Minecraft\n"
+		     "# server is executed.\n"
+		     "motd=%s\n"
+		     "server-port=%" PRIu16 "\n"
+		     "enable-rcon=true\n"
+		     "rcon.port=%" PRIu16 "\n"
+		     "rcon.password=%s",
+		     name, mc_port, rcon_port,
+		     rcon_password ? rcon_password : hexrnd);
+	if (r < 0) {
+		error("asprintf failed: %m");
+		return NULL;
+	}
+
+	if (len)
+		*len = r;
+	return (unsigned char *)properties;
+}
+
+static uint16_t get_port(struct list_head *list)
+{
+	struct saddr *saddr;
+
+	if (!list || list_empty(list))
+		return 0;
+
+	list_for_each_entry(saddr, list, list) {
+		switch (saddr->st.ss_family) {
+		case AF_INET:
+			if (saddr->in4.sin_addr.s_addr == htonl(INADDR_LOOPBACK) ||
+			    saddr->in4.sin_addr.s_addr == htonl(INADDR_ANY) ||
+			    saddr->in4.sin_addr.s_addr == htonl(INADDR_BROADCAST))
+				return htons(saddr->in4.sin_port);
+			break;
+		case AF_INET6:
+			if (!memcmp(&saddr->in6.sin6_addr, &in6addr_any,
+				    sizeof(saddr->in6.sin6_addr)) ||
+			    !memcmp(&saddr->in6.sin6_addr, &in6addr_loopback,
+				    sizeof(saddr->in6.sin6_addr)))
+				return htons(saddr->in6.sin6_port);
+			break;
+		}
+	}
+
+	return 0;
+}
+
+static bool saddr_port_match(struct list_head *list, uint16_t port)
+{
+	struct saddr *a;
+
+	list_for_each_entry(a, list, list) {
+		switch (a->st.ss_family) {
+		case AF_INET:
+			if (a->in4.sin_port == port)
+				return true;
+			break;
+
+		case AF_INET6:
+			if (a->in6.sin6_port == port)
+				return true;
+			break;
+
+		default:
+			break;
+		}
+	}
+
+	return false;
+}
+
+static bool select_free_ports(struct cfg *cfg, uint16_t *listen_port,
+			      uint16_t *mc_port, uint16_t *rcon_port)
+{
+	uint16_t lport = cfg->listen_port_min;
+	uint16_t mport = cfg->mc_port_min;
+	uint16_t rport = cfg->rcon_port_min;
+	struct server *server;
+	bool used;
+
+	for (lport = cfg->listen_port_min,
+	     mport = cfg->mc_port_min,
+	     rport = cfg->rcon_port_min;
+	     lport <= cfg->listen_port_max &&
+	     mport <= cfg->mc_port_max &&
+	     rport <= cfg->rcon_port_max;
+	     lport++, mport++, rport++) {
+
+		used = false;
+
+		list_for_each_entry(server, &cfg->servers, list) {
+			if (!server->scfg.filename)
+				continue;
+
+			if (saddr_port_match(&server->scfg.locals, lport)) {
+				used = true;
+				break;
+			}
+
+			if (saddr_port_match(&server->scfg.remotes, mport)) {
+				used = true;
+				break;
+			}
+
+			if (saddr_port_match(&server->scfg.rcons, rport)) {
+				used = true;
+				break;
+			}
+		}
+
+		if (!used ) {
+			if (listen_port && *listen_port == 0)
+				*listen_port = lport;
+
+			if (mc_port && *mc_port == 0)
+				*mc_port = mport;
+
+			if (rcon_port && *rcon_port == 0)
+				*rcon_port = rport;
+
+			return true;
+		}
+	}
+
+	return false;
+}
+
 bool do_new(struct cfg *cfg)
 {
 	const char *name = cfg->commands[0];
 	struct server *server;
-	int sfd = -1;
-	bool rv = false;
+	struct server *defserver = NULL;
+	_cleanup_free_ unsigned char *properties = NULL;
+	size_t properties_len;
+	_cleanup_close_ int sfd = -1;
+	uint16_t rcon_port = 0, mc_port = 0;
+	const char *rcon_password = NULL;
 
 	if (!valid_name(name))
 		return false;
@@ -316,33 +483,52 @@ bool do_new(struct cfg *cfg)
 	server_load_all_known(cfg);
 
 	if (!cfg->dir)
-		goto out;
+		return false;
 
 	list_for_each_entry(server, &cfg->servers, list) {
-		if (streq(server->name, name)) {
+		if (!server->scfg.filename) {
+			defserver = server;
+			continue;
+		}
+
+		if (streq(server->scfg.filename, filename)) {
 			error("Server \"%s\" already exists", name);
-			goto out;
+			return false;
 		}
 	}
 
+	if (defserver) {
+		/* FIXME: check list empty and tailor error msg */
+		rcon_port = get_port(&defserver->scfg.rcons);
+		mc_port = get_port(&defserver->scfg.remotes);
+		rcon_password = defserver->scfg.rcon_password;
+	} else if (cfg->rcon_password)
+		rcon_password = cfg->rcon_password;
+
+	if (!select_free_ports(cfg, NULL, &mc_port, &rcon_port)) {
+		error("Failed to find a free port");
+		return false;
+	}
+
 	sfd = open_subdir(dirfd(cfg->dir), "../servers", false);
 	if (sfd < 0) {
 		error("Failed to open configuration directory \"servers\"");
-		goto out;
+		return false;
 	}
 
-	if (!create_server_cfg(sfd, dirfd(cfg->dir), name, filename))
-		goto out;
-
-	info("Created server configuration %s", name);
+	properties = create_mc_properties(name, mc_port, rcon_port,
+					  rcon_password, &properties_len);
+	if (!properties)
+		return false;
 
-	rv = true;
+	error("Created config file (%zu):\n%s", properties_len, properties);
 
-out:
-	if (sfd >= 0)
-		close(sfd);
+	if (!create_server_cfg(sfd, dirfd(cfg->dir), name, filename, properties,
+			       properties_len))
+		return false;
 
-	return rv;
+	info("Created server configuration %s", name);
+	return true;
 }
 
 bool do_list(struct cfg *cfg)
diff --git a/shared/utils.h b/shared/utils.h
index 9404323..c47f9a5 100644
--- a/shared/utils.h
+++ b/shared/utils.h
@@ -10,6 +10,7 @@
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <netinet/ip.h>
+#include <unistd.h>
 
 extern unsigned debug_mask;
 
@@ -127,4 +128,18 @@ static inline bool strcaseeq(const char *a, const char *b)
 
 #define DIV_ROUND_UP(n, d) (((n) + (d)-1) / (d))
 
+#define _cleanup_(x) __attribute__((cleanup(x)))
+
+static inline void closep(int *fd)
+{
+	if (*fd && *fd >= 0)
+		close(*fd);
+}
+#define _cleanup_close_ _cleanup_(closep)
+
+static inline void freep(void *p) {
+	xfree(*(void**)p);
+}
+#define _cleanup_free_ _cleanup_(freep)
+
 #endif