shell fixes

3 files changed, 31 insertions, 6 deletions

diff --git a/src/firejail/bandwidth.c b/src/firejail/bandwidth.c
index 22be5b23c..4a1df9c67 100644
--- a/src/firejail/bandwidth.c
+++ b/src/firejail/bandwidth.c
@@ -450,7 +450,12 @@ void bandwidth_pid(pid_t pid, const char *command, const char *dev, int down, in
         if (setregid(0, 0))
                 errExit("setregid");
 
-        assert(cfg.shell);
+        if (!cfg.shell)
+                cfg.shell = guess_shell();
+        if (!cfg.shell) {
+                fprintf(stderr, "Error: no POSIX shell found, please use --shell command line option\n");
+                exit(1);
+        }
 
         char *arg[4];
         arg[0] = cfg.shell;
diff --git a/src/firejail/env.c b/src/firejail/env.c
index 2c8be3852..2cc65e464 100644
--- a/src/firejail/env.c
+++ b/src/firejail/env.c
@@ -121,6 +121,8 @@ void env_defaults(void) {
                 errExit("setenv");
         if (setenv("container", "firejail", 1) < 0) // LXC sets container=lxc,
                 errExit("setenv");
+        if (!cfg.shell)
+                cfg.shell = guess_shell();
         if (cfg.shell && setenv("SHELL", cfg.shell, 1) < 0)
                 errExit("setenv");
 
diff --git a/src/firejail/join.c b/src/firejail/join.c
index 37bac7e65..948c7ef71 100644
--- a/src/firejail/join.c
+++ b/src/firejail/join.c
@@ -319,10 +319,13 @@ void join(pid_t pid, int argc, char **argv, int index) {
                         caps_set(caps);
 
                 // set prompt color to green
-                //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");
-
+                char *prompt = getenv("FIREJAIL_PROMPT");
+                if (prompt && strcmp(prompt, "yes") == 0) {
+                        //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 nice
                 if (arg_nice) {
                         errno = 0;
@@ -336,7 +339,22 @@ void join(pid_t pid, int argc, char **argv, int index) {
 
                 // run cmdline trough shell
                 if (cfg.command_line == NULL) {
-                        assert(cfg.shell);
+                        // if the sandbox was started with --shell=none, it is possible we don't have a shell
+                        // inside the sandbox
+                        if (cfg.shell == NULL) {
+                                cfg.shell = guess_shell();
+                                if (!cfg.shell) {
+                                        fprintf(stderr, "Error: no POSIX shell found, please use --shell command line option\n");
+                                        exit(1);
+                                }
+                        }
+                                
+                        struct stat s;
+                        if (stat(cfg.shell, &s) == -1)  {
+                                fprintf(stderr, "Error: %s shell not found inside the sandbox\n", cfg.shell);
+                                exit(1);
+                        }
+
                         cfg.command_line = cfg.shell;
                         cfg.window_title = cfg.shell;
                 }