api: add API level 6

API level 6 allows callers to use both the TSYNC and notify APIs at
the same time.  This is due to the TSYNC_ESRCH flag which was added
in Linux v5.7.

This patch also fixes some omissions in seccomp_api_set().

Acked-by: Tom Hromatka <tom.hromatka@oracle.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

1 files changed, 116 insertions, 0 deletions

diff --git a/tests/58-live-tsync_notify.c b/tests/58-live-tsync_notify.c
new file mode 100644
index 0000000..86e1b0c
--- /dev/null
+++ b/tests/58-live-tsync_notify.c
@@ -0,0 +1,116 @@
+/**
+ * Seccomp Library test program
+ *
+ * Copyright (c) 2019 Cisco Systems, Inc. <pmoore2@cisco.com>
+ * Author: Paul Moore <paul@paul-moore.com>
+ */
+
+/*
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, see <http://www.gnu.org/licenses>.
+ */
+
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <seccomp.h>
+#include <signal.h>
+#include <syscall.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include "util.h"
+
+#define MAGIC 0x1122334455667788UL
+
+int main(int argc, char *argv[])
+{
+	int rc, fd = -1, status;
+	struct seccomp_notif *req = NULL;
+	struct seccomp_notif_resp *resp = NULL;
+	scmp_filter_ctx ctx = NULL;
+	pid_t pid = 0;
+
+	ctx = seccomp_init(SCMP_ACT_ALLOW);
+	if (ctx == NULL)
+		return ENOMEM;
+
+	rc = seccomp_attr_set(ctx, SCMP_FLTATR_CTL_TSYNC, 1);
+	if (rc)
+		goto out;
+
+	rc = seccomp_rule_add(ctx, SCMP_ACT_NOTIFY, SCMP_SYS(getpid), 0, NULL);
+	if (rc)
+		goto out;
+
+	rc  = seccomp_load(ctx);
+	if (rc < 0)
+		goto out;
+
+	rc = seccomp_notify_fd(ctx);
+	if (rc < 0)
+		goto out;
+	fd = rc;
+
+	pid = fork();
+	if (pid == 0)
+		exit(syscall(SCMP_SYS(getpid)) != MAGIC);
+
+	rc = seccomp_notify_alloc(&req, &resp);
+	if (rc)
+		goto out;
+
+	rc = seccomp_notify_receive(fd, req);
+	if (rc)
+		goto out;
+	if (req->data.nr != SCMP_SYS(getpid)) {
+		rc = -EFAULT;
+		goto out;
+	}
+	rc = seccomp_notify_id_valid(fd, req->id);
+	if (rc)
+		goto out;
+
+	resp->id = req->id;
+	resp->val = MAGIC;
+	resp->error = 0;
+	resp->flags = 0;
+	rc = seccomp_notify_respond(fd, resp);
+	if (rc)
+		goto out;
+
+	if (waitpid(pid, &status, 0) != pid) {
+		rc = -EFAULT;
+		goto out;
+	}
+
+	if (!WIFEXITED(status)) {
+		rc = -EFAULT;
+		goto out;
+	}
+	if (WEXITSTATUS(status)) {
+		rc = -EFAULT;
+		goto out;
+	}
+
+out:
+	if (fd >= 0)
+		close(fd);
+	if (pid)
+		kill(pid, SIGKILL);
+	seccomp_notify_free(req, resp);
+	seccomp_release(ctx);
+
+	if (rc != 0)
+		return (rc < 0 ? -rc : rc);
+	return 160;
+}