jail: add JID, JNAME and JPATH to environment for exec.* commands

usr.sbin/jail/command.c

@@ -290,7 +290,7 @@ run_command(struct cfjail *j)
 	const struct cfstring *comstring, *s;
 	login_cap_t *lcap;
 	const char **argv;
-	char *acs, *cs, *comcs, *devpath;
+	char *acs, *ajidstr, *cs, *comcs, *devpath;
 	const char *jidstr, *conslog, *fmt, *path, *ruleset, *term, *username;
 	enum intparam comparam;
 	size_t comlen, ret;
@@ -795,6 +795,18 @@ run_command(struct cfjail *j)
 		}
 		endpwent();
 	}
+	if (!injail) {
+		if (asprintf(&ajidstr, "%d", j->jid) == -1) {
+			jail_warnx(j, "asprintf jid=%d: %s", j->jid,
+				strerror(errno));
+			exit(1);
+		}
+		setenv("JID", ajidstr, 1);
+		free(ajidstr);
+		setenv("JNAME", string_param(j->intparams[KP_NAME]), 1);
+		path = string_param(j->intparams[KP_PATH]);
+		setenv("JPATH", path ? path : "", 1);
+	}
 
 	if (consfd != 0 && (dup2(consfd, 1) < 0 || dup2(consfd, 2) < 0)) {
 		jail_warnx(j, "exec.consolelog: %s", strerror(errno));

usr.sbin/jail/jail.8

@@ -819,6 +819,22 @@ commands in sequence.
 All commands must succeed (return a zero exit status), or the jail will
 not be created or removed, as appropriate.
 .Pp
+The following variables are added to the environment:
+.Bl -tag -width indent -offset indent
+.It Ev JID
+The
+.Va jid
+, or jail identifier.
+.It Ev JNAME
+The
+.Va name
+of the jail.
+.It Ev JPATH
+The
+.Va path
+of the jail.
+.El
+.Pp
 The pseudo-parameters are:
 .Bl -tag -width indent
 .It Va exec.prepare
@@ -883,6 +899,10 @@ is imported from the current environment.
 is set to "/bin:/usr/bin".
 The environment variables from the login class capability database for the
 target login are also set.
+.Ev JID , JNAME
+and
+.Ev JPATH
+are not set.
 If a user is specified (as with
 .Va exec.jail_user ) ,
 commands are run from that (possibly jailed) user's directory.

usr.sbin/jail/tests/commands.jail.conf

@@ -1,6 +1,9 @@
 
 exec.prestop = "echo STOP";
 exec.prestart = "echo START";
+exec.poststart = "env";
 persist;
 
+path = "/tmp/test_${name}_root";
+
 basejail {}

usr.sbin/jail/tests/jail_basic_test.sh

@@ -129,13 +129,19 @@ commands_head()
 {
 	atf_set descr 'Commands jail test'
 	atf_set require.user root
+	mkdir /tmp/test_basejail_root
 }
 
 commands_body()
 {
-	# exec.prestart
-	atf_check -s exit:0 -o inline:"START\n" \
+	# exec.prestart (START) and exec.poststart (env)
+	atf_check -s exit:0 -o save:stdout -e empty \
 		jail -f $(atf_get_srcdir)/commands.jail.conf -qc basejail
+	grep -E '^START$' stdout || atf_fail "exec.prestart output not found"
+	grep -E '^JID=[0-9]+' stdout || atf_fail "JID not found in exec.poststart env output"
+	grep -E '^JNAME=basejail$' stdout || atf_fail "JNAME not found in exec.poststart env output"
+	grep -E '^JPATH=/tmp/test_basejail_root$' stdout || atf_fail "JPATH not found in exec.poststart env output"
+
 	# exec.prestop by jailname
 	atf_check -s exit:0 -o inline:"STOP\n" \
 		jail -f $(atf_get_srcdir)/commands.jail.conf -qr basejail 
@@ -152,6 +158,7 @@ commands_cleanup()
 	then
 	    jail -r basejail
 	fi
+	rmdir /tmp/test_basejail_root
 }
 
 atf_init_test_cases()