Merge pull request #1 from IoIxD/idk

support launching into wayland sessions, set xdg vars, visually show errors upon pam errors.

mdm/login.c

@@ -1,20 +1,26 @@
 #include "mdm.h"
 
 #include <ini.h>
+#include <sched.h>
+#include <security/_pam_types.h>
 #include <security/pam_appl.h>
 #include <stb_ds.h>
+#include <stdlib.h>
+#include <string.h>
 
 MwWidget root;
-MwWidget window, sesscombo, usercombo, passentry;
+MwWidget window, sesscombo, usercombo, passentry, error;
 
 typedef struct session {
-	char* key;
+	char*		       key;
-	char* value;
+	session_environment_t* value;
 } session_t;
 
-session_t* sessions = NULL;
+session_t* sessions	      = NULL;
-char*	   name_line;
+char*	   name_line	      = NULL;
-char*	   exec_line;
+char*	   try_exec_line      = NULL;
+char*	   exec_line	      = NULL;
+char*	   desktop_names_line = NULL;
 
 static void add_user(const char* name, void* user) {
 	MwComboBoxAdd(user, -1, name);
@@ -25,42 +31,61 @@ static int dumper(void* user, const char* section, const char* name, const char*
 
 	if(strcmp(name, "Name") == 0) {
 		name_line = MDEStringDuplicate(value);
+	} else if(strcmp(name, "TryExec") == 0) {
+		try_exec_line = MDEStringDuplicate(value);
 	} else if(strcmp(name, "Exec") == 0) {
 		exec_line = MDEStringDuplicate(value);
+	} else if(strcmp(name, "DesktopNames") == 0) {
+		desktop_names_line = MDEStringDuplicate(value);
 	}
 
 	return 1;
 }
 
-static void add_session(const char* path, int dir, int symlink, void* user) {
+static void add_session(session_type_t session_type, const char* path, int dir, int symlink, void* user) {
-	int m = 1;
+	int		       m     = 1;
+	session_environment_t* value = malloc(sizeof(session_environment_t));
+
+	name_line	   = NULL;
+	exec_line	   = NULL;
+	try_exec_line	   = NULL;
+	desktop_names_line = NULL;
 
-	name_line = NULL;
-	exec_line = NULL;
-	
 	if(dir || symlink) return;
 
 	ini_parse(path, dumper, user);
 
-	if(name_line != NULL && exec_line != NULL) {
+	if(name_line != NULL && (exec_line != NULL || try_exec_line != NULL)) {
 		int i;
-		for(i = 0; i < shlen(sessions); i++){
+		for(i = 0; i < shlen(sessions); i++) {
 			if(strcmp(sessions[i].key, name_line) == 0) break;
 		}
-	
+
-		if(i == shlen(sessions)){	
+		if(i == shlen(sessions)) {
 			MwComboBoxAdd(user, -1, name_line);
 
-			shput(sessions, name_line, exec_line);
+			value->run	     = exec_line;
+			value->try_run	     = try_exec_line;
+			value->session_type  = session_type;
+			value->desktop_names = desktop_names_line;
+			shput(sessions, name_line, value);
 
 			m = 0;
 		}
 	}
 
 	if(name_line != NULL) free(name_line);
+	if(desktop_names_line != NULL) free(desktop_names_line);
+	if(m && try_exec_line != NULL) free(try_exec_line);
 	if(m && exec_line != NULL) free(exec_line);
 }
 
+static void add_session_x(const char* path, int dir, int symlink, void* user) {
+	add_session(MDM_SESSION_TYPE_X, path, dir, symlink, user);
+}
+static void add_session_wayland(const char* path, int dir, int symlink, void* user) {
+	add_session(MDM_SESSION_TYPE_WAYLAND, path, dir, symlink, user);
+}
 static int conversation(int num_msg, const struct pam_message** msg, struct pam_response** resp, void* appdata) {
 	int i;
 
@@ -82,53 +107,85 @@ static int conversation(int num_msg, const struct pam_message** msg, struct pam_
 }
 
 static void try_login(MwWidget handle, void* user, void* client) {
-	const char*	username = MwComboBoxGet(usercombo, MwGetInteger(usercombo, MwNvalue));
+	const char*	username;
-	struct pam_conv conv	 = {conversation, NULL};
+	const char*	place;
+	struct pam_conv conv;
 	pam_handle_t*	pam;
+	int		err;
+	int		err2;
 	int		ret;
-	jmp_buf		cleanup;
+	char		err_str[255];
-	int		err = 1;
+	int		print_error = 0;
+	int		i, n;
+
+	username	 = MwComboBoxGet(usercombo, MwGetInteger(usercombo, MwNvalue));
+	conv.conv	 = conversation;
+	conv.appdata_ptr = NULL;
+	err		 = 1;
 
 	(void)handle;
 	(void)user;
 	(void)client;
 
-	if(setjmp(cleanup)) {
-		pam_end(pam, 0);
-
-		if(err) {
-			MwSetText(passentry, MwNtext, "");
-		} else {
-			struct passwd* pwd     = getpwnam(username);
-			const char*    session = MwComboBoxGet(sesscombo, MwGetInteger(sesscombo, MwNvalue));
-
-			uid = pwd->pw_uid;
-			gid = pwd->pw_gid;
-			run = shget(sessions, session);
-
-			MwDestroyWidget(root);
-		}
-
-		return;
-	}
-
 	ret = pam_start("mdm", username, &conv, &pam);
 	if(ret != PAM_SUCCESS) {
-		longjmp(cleanup, 1);
+		place = "Error calling pam_start";
+		goto cleanup;
 	}
 
 	ret = pam_authenticate(pam, 0);
 	if(ret != PAM_SUCCESS) {
-		longjmp(cleanup, 1);
+		place = "Error calling pam_authenticate";
+		goto cleanup;
 	}
 
 	ret = pam_acct_mgmt(pam, 0);
 	if(ret != PAM_SUCCESS) {
-		longjmp(cleanup, 1);
+		place = "Error calling pam_acct_mgmt";
+		goto cleanup;
 	}
 
-	err = 0;
+	ret = pam_open_session(pam, 0);
-	longjmp(cleanup, 1);
+	if(ret != PAM_SUCCESS) {
+		place = "Error calling pam_open_session";
+		goto cleanup;
+	}
+cleanup:
+	pam_close_session(pam, 0);
+
+	// if pam_end fails but we have another error, we care more about the error at hand
+	// then whether pam successfully ended.
+	err2 = pam_end(pam, 0);
+
+	if(err && ret != PAM_SUCCESS) {
+		MwSetText(passentry, MwNtext, "");
+		snprintf(err_str, 255, "%s: %s", place, pam_strerror(pam, err));
+		print_error = 1;
+	} else if(err2) {
+		MwSetText(passentry, MwNtext, "");
+		snprintf(err_str, 255, "Error calling pam_end: %s", pam_strerror(pam, err2));
+		print_error = 1;
+	}
+	if(print_error) {
+		n = 0;
+		for(i = 0; err_str[i] != '\0' && i <= 255; i++ && n++) {
+			if(err_str[i] == ' ' && n >= 40) {
+				err_str[i] = '\n';
+				n	   = 0;
+			}
+		}
+		MwSetText(error, MwNtext, err_str);
+	} else {
+		printf("Logging in as %s\n", username);
+		struct passwd* pwd     = getpwnam(username);
+		const char*    session = MwComboBoxGet(sesscombo, MwGetInteger(sesscombo, MwNvalue));
+
+		uid = pwd->pw_uid;
+		gid = pwd->pw_gid;
+		env = shget(sessions, session);
+
+		MwDestroyWidget(root);
+	}
 }
 
 void login_window(void) {
@@ -143,7 +200,7 @@ void login_window(void) {
 
 	root = MwCreateWidget(NULL, "root", NULL, 0, 0, 0, 0);
 
-	window	  = MwVaCreateWidget(MwWindowClass, "login", root, (x_width() - 366) / 2, (x_height() - 183) / 2, 366, 183,
+	window	  = MwVaCreateWidget(MwWindowClass, "login", root, (x_width() - 366) / 2, (x_height() - 200) / 2, 366, 250,
 				     MwNtitle, "login",
 				     NULL);
 	p	  = config_picture == NULL ? NULL : MwLoadImage(window, config_picture);
@@ -179,7 +236,7 @@ void login_window(void) {
 	ok	  = MwVaCreateWidget(MwButtonClass, "ok", window, 366 - 10 - 60, 10 + 137 + 10, 60, 18,
 				     MwNtext, "OK",
 				     NULL);
-
+	error	  = MwVaCreateWidget(MwLabelClass, "error", window, 10, 10 + 137 + 10 + 20, 366, 48, NULL);
 	if(p != NULL) MwVaApply(pic, MwNpixmap, p, NULL);
 
 	MwAddUserHandler(ok, MwNactivateHandler, try_login, NULL);
@@ -193,8 +250,10 @@ void login_window(void) {
 	shfree(sessions);
 	sh_new_strdup(sessions);
 	shdefault(sessions, NULL);
-	MDEDirectoryScan(DATADIR "/xsessions", add_session, sesscombo);
+	MDEDirectoryScan(DATADIR "/xsessions", add_session_x, sesscombo);
-	MDEDirectoryScan("/usr/share/xsessions", add_session, sesscombo);
+	MDEDirectoryScan("/usr/share/xsessions", add_session_x, sesscombo);
+	MDEDirectoryScan(DATADIR "/wayland-sessions", add_session_wayland, sesscombo);
+	MDEDirectoryScan("/usr/share/wayland-sessions", add_session_wayland, sesscombo);
 
 	pthread_mutex_unlock(&xmutex);
 

mdm/main.c

@@ -1,14 +1,21 @@
 #include "mdm.h"
+#include <sched.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
 int is_launch_x = 1;
-int is_daemon = 1;
+int is_daemon	= 1;
 
-gid_t gid;
+gid_t		       gid;
-uid_t uid;
+uid_t		       uid;
-char* run;
+session_environment_t* env;
+
+static void set_env_standard(struct passwd* pwd);
+static void set_env_xdg(struct passwd* pwd);
 
 int main(int argc, char** argv) {
-	int   i, st;
+	int   i, st, exit;
 	char* backup = NULL;
 	pid_t pid;
 
@@ -16,7 +23,7 @@ int main(int argc, char** argv) {
 		if(argv[i][0] == '-') {
 			if(strcmp(argv[i], "-X") == 0 || strcmp(argv[i], "--no-launch-x") == 0) {
 				is_launch_x = 0;
-			}else if(strcmp(argv[i], "-d") == 0 || strcmp(argv[i], "--no-daemon") == 0) {
+			} else if(strcmp(argv[i], "-d") == 0 || strcmp(argv[i], "--no-daemon") == 0) {
 				is_daemon = 0;
 			} else {
 				fprintf(stderr, "%s: bad option: %s\n", argv[0], argv[i]);
@@ -30,7 +37,7 @@ int main(int argc, char** argv) {
 		return 1;
 	}
 
-	if(is_daemon && (pid = fork()) != 0){
+	if(is_daemon && (pid = fork()) != 0) {
 		FILE* f = fopen("/var/run/mdm.pid", "w");
 		fprintf(f, "%d\n", pid);
 		fclose(f);
@@ -52,7 +59,7 @@ int main(int argc, char** argv) {
 
 		login_window();
 
-		if(run == NULL) continue;
+		if(env->run == NULL && env->try_run == NULL) continue;
 
 		if((pid = fork()) == 0) {
 			struct passwd* pwd = getpwuid(uid);
@@ -60,18 +67,62 @@ int main(int argc, char** argv) {
 			setgid(gid);
 			setuid(uid);
 			chdir(pwd->pw_dir);
-			setenv("USER", pwd->pw_name, 1);
+
-			setenv("SHELL", pwd->pw_shell, 1);
+			set_env_standard(pwd);
-			setenv("HOME", pwd->pw_dir, 1);
+			set_env_xdg(pwd);
-			_exit(system(run));
+
+			if((exit = system(env->try_run)) != 0) {
+				exit = system(env->run);
+			} else {
+				_exit(exit);
+			}
 		} else {
 			waitpid(pid, NULL, 0);
 		}
 
 		if(is_launch_x) {
+			unsetenv("DISPLAY");
 			kill_x();
 		}
 	} while(is_launch_x);
 
 	if(backup != NULL) free(backup);
 }
+
+void set_env_standard(struct passwd* pwd) {
+	setenv("HOME", pwd->pw_dir, 1);
+	setenv("PWD", pwd->pw_dir, 1);
+	setenv("USER", pwd->pw_name, 1);
+	setenv("SHELL", pwd->pw_shell, 1);
+	setenv("LOGNAME", pwd->pw_shell, 1);
+}
+void set_env_xdg(struct passwd* pwd) {
+	// this directory isn't avaliable on bsd, but we can't check for all of them.
+	// so just assume it's only on linux, idek if that's true but who care
+#if defined(__linux__)
+	char runtime_dir[255];
+	snprintf(runtime_dir, 255, "/run/user/%d", pwd->pw_uid);
+	setenv("XDG_RUNTIME_DIR", runtime_dir, 1);
+#endif
+
+	switch(env->session_type) {
+	case MDM_SESSION_TYPE_X:
+		setenv("XDG_SESSION_TYPE", "x11", 1);
+		break;
+	case MDM_SESSION_TYPE_WAYLAND:
+		setenv("XDG_SESSION_TYPE", "wayland", 1);
+		break;
+	}
+
+	if(env->desktop_names) {
+		if(strlen(env->desktop_names) > 1) {
+			setenv("XDG_SESSION_DESKTOP", strtok(env->desktop_names, ";"), 1);
+		}
+		setenv("XDG_CURRENT_DESKTOP", env->desktop_names, 1);
+	}
+
+	setenv("XDG_SESSION_CLASS", "user", 1);
+	setenv("XDG_SESSION_ID", "1", 1);
+	setenv("XDG_SEAT", "seat0", 1);
+	// setenv("XDG_VTNR", "/dev/pts/7", 1);
+}

mdm/mdm.h

@@ -22,10 +22,25 @@
 #include <setjmp.h>
 #include <pthread.h>
 
+/* login.c */
+extern MwWidget root;
+typedef enum session_type {
+	MDM_SESSION_TYPE_X,
+	MDM_SESSION_TYPE_WAYLAND,
+} session_type_t;
+typedef struct session_environment {
+	char*	       run;
+	char*	       try_run;
+	session_type_t session_type;
+	char*	       desktop_names;
+} session_environment_t;
+
+void login_window(void);
+
 /* main.c */
-extern gid_t gid;
+extern gid_t		      gid;
-extern uid_t uid;
+extern uid_t		      uid;
-extern char* run;
+extern session_environment_t* env;
 
 /* xserver.c */
 extern pthread_t       xthread;
@@ -39,11 +54,6 @@ int  init_x(void);
 void loop_x(void);
 void kill_x(void);
 
-/* login.c */
-extern MwWidget root;
-
-void login_window(void);
-
 /* config.c */
 extern char* config_picture;
 

mdm/xserver.c

@@ -1,3 +1,4 @@
+#include <stdlib.h>
 #define _MILSKO
 #define USE_X11
 #include "mdm.h"
@@ -22,8 +23,6 @@ int launch_x(void) {
 
 	signal(SIGUSR1, catch_usr1);
 
-	/* TODO: Remove hardcoded DISPLAY */
-
 	if((xserver = fork()) == 0) {
 		signal(SIGUSR1, SIG_IGN);
 		execlp("X", "X", ":0", NULL);