major cleanup

1 files changed, 108 insertions, 0 deletions

diff --git a/src/fseccomp/seccomp_file.c b/src/fseccomp/seccomp_file.c
new file mode 100644
index 000000000..10ef9dd31
--- /dev/null
+++ b/src/fseccomp/seccomp_file.c
@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2014-2016 Firejail Authors
+ *
+ * This file is part of firejail project
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+#include "fseccomp.h"
+#include "../include/seccomp.h"
+#include <sys/syscall.h>
+
+static void write_to_file(int fd, void *data, int size) {
+        assert(data);
+        assert(size);
+        
+        int written = 0;
+        while (written < size) {
+                int rv = write(fd, (unsigned char *) data + written, size - written);
+                if (rv == -1) {
+                        fprintf(stderr, "Error fseccomp: cannot write seccomp file\n");
+                        exit(1);
+                }
+                written += rv;
+        }
+}
+
+void filter_init(int fd) {
+#if defined(__x86_64__)
+#define X32_SYSCALL_BIT 0x40000000
+        struct sock_filter filter[] = {
+                VALIDATE_ARCHITECTURE,
+                EXAMINE_SYSCALL,
+                // handle X32 ABI
+                BPF_JUMP(BPF_JMP+BPF_JGE+BPF_K, X32_SYSCALL_BIT, 1, 0),
+                BPF_JUMP(BPF_JMP+BPF_JGE+BPF_K, 0, 1, 0),
+                RETURN_ERRNO(EPERM)
+        };
+#else
+        struct sock_filter filter[] = {
+                VALIDATE_ARCHITECTURE,
+                EXAMINE_SYSCALL
+        };
+#endif
+
+#if 0
+{
+        int i;
+        unsigned char *ptr = (unsigned char *) &filter[0];
+        for (i = 0; i < sizeof(filter); i++, ptr++)
+                printf("%x, ", (*ptr) & 0xff);
+        printf("\n");
+}
+#endif
+
+        write_to_file(fd, filter, sizeof(filter));
+}
+
+void filter_add_whitelist(int fd, int syscall, int arg) {
+        (void) arg;
+        
+        struct sock_filter filter[] = {
+                WHITELIST(syscall)
+        };
+        write_to_file(fd, filter, sizeof(filter));
+}
+
+void filter_add_blacklist(int fd, int syscall, int arg) {
+        (void) arg;
+        
+        struct sock_filter filter[] = {
+                BLACKLIST(syscall)
+        };
+        write_to_file(fd, filter, sizeof(filter));
+}
+
+void filter_add_errno(int fd, int syscall, int arg) {
+        struct sock_filter filter[] = {
+                BLACKLIST_ERRNO(syscall, arg)
+        };
+        write_to_file(fd, filter, sizeof(filter));
+}
+
+void filter_end_blacklist(int fd) {
+        struct sock_filter filter[] = {
+                RETURN_ALLOW
+        };
+        write_to_file(fd, filter, sizeof(filter));
+}
+
+void filter_end_whitelist(int fd) {
+        struct sock_filter filter[] = {
+                KILL_PROCESS
+        };
+        write_to_file(fd, filter, sizeof(filter));
+}
+