config support for firejail prompt in terminals

RELNOTES

@@ -13,6 +13,7 @@ firejail (0.9.45) baseline; urgency=low
   * feature: private /opt directory (--private-opt, profile support)
   * feature: private /srv directory (--private-srv, profile support)
   * feature: spoof machine-id
+  * feature: config support for firejail prompt in terminal
   * new profiles: xiphos, Tor Browser Bundle, display (imagemagik), Wire,
   * new profiles: mumble, zoom, Guayadeque, qemu, keypass2, xed, pluma,
   * new profiles: Cryptocat, Bless, Gnome 2048, Gnome Calculator, 

etc/firejail.config

@@ -17,6 +17,9 @@
 # Enable or disable file transfer support, default enabled.
 # file-transfer yes
 
+# Enable Firejail green prompt in terminal, default disabled
+# firejail-prompt no
+
 # Force use of nonewprivs.  This mitigates the possibility of
 # a user abusing firejail's features to trick a privileged (suid
 # or file capabilities) process into loading code or configuration

src/firejail/checkcfg.c

@@ -43,6 +43,7 @@ int checkcfg(int val) {
 		cfg_val[CFG_RESTRICTED_NETWORK] = 0; // disabled by default
 		cfg_val[CFG_FORCE_NONEWPRIVS] = 0; // disabled by default
 		cfg_val[CFG_PRIVATE_BIN_NO_LOCAL] = 0; // disabled by default
+		cfg_val[CFG_FIREJAIL_PROMPT] = 0; // disabled by default
 		
 		// open configuration file
 		char *fname;
@@ -126,6 +127,15 @@ int checkcfg(int val) {
 				else
 					goto errout;
 			}
+			// prompt
+			else if (strncmp(ptr, "firejail-prompt ", 16) == 0) {
+				if (strcmp(ptr + 16, "yes") == 0)
+					cfg_val[CFG_FIREJAIL_PROMPT] = 1;
+				else if (strcmp(ptr + 16, "no") == 0)
+					cfg_val[CFG_FIREJAIL_PROMPT] = 0;
+				else
+					goto errout;
+			}
 			// nonewprivs
 			else if (strncmp(ptr, "force-nonewprivs ", 17) == 0) {
 				if (strcmp(ptr + 17, "yes") == 0)

src/firejail/env.c

@@ -129,13 +129,21 @@ void env_defaults(void) {
 		errExit("setenv");
 
 	// set prompt color to green
-	char *prompt = getenv("FIREJAIL_PROMPT");
-	if (prompt && strcmp(prompt, "yes") == 0) {
+	int set_prompt = 0;
+	if (checkcfg(CFG_FIREJAIL_PROMPT))
+		set_prompt = 1;
+	else { // check FIREJAIL_PROMPT="yes" environment variable
+		char *prompt = getenv("FIREJAIL_PROMPT");
+		if (prompt && strcmp(prompt, "yes") == 0)
+			set_prompt = 1;
+	}
+	
+	if (set_prompt) {
 		//export PS1='\[\e[1;32m\][\u@\h \W]\$\[\e[0m\] '
 		if (setenv("PROMPT_COMMAND", "export PS1=\"\\[\\e[1;32m\\][\\u@\\h \\W]\\$\\[\\e[0m\\] \"", 1) < 0)
 			errExit("setenv");
 	}
-
+	
 	// set the window title
 	if (!arg_quiet)
 		printf("\033]0;firejail %s\007", cfg.window_title);

src/firejail/firejail.h

@@ -661,6 +661,7 @@ enum {
 	CFG_CHROOT_DESKTOP,
 	CFG_PRIVATE_HOME,
 	CFG_PRIVATE_BIN_NO_LOCAL,
+	CFG_FIREJAIL_PROMPT,
 	CFG_MAX // this should always be the last entry
 };
 extern char *xephyr_screen;