Added seccomp support

1 files changed, 157 insertions, 0 deletions

diff --git a/frida_mode/src/seccomp/seccomp.c b/frida_mode/src/seccomp/seccomp.c
new file mode 100644
index 00000000..7683cd71
--- /dev/null
+++ b/frida_mode/src/seccomp/seccomp.c
@@ -0,0 +1,157 @@
+#include <execinfo.h>
+#include <fcntl.h>
+#include <linux/seccomp.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "frida-gumjs.h"
+
+#include "debug.h"
+
+#include "seccomp.h"
+#include "util.h"
+
+char *seccomp_filename = NULL;
+
+static void seccomp_vprint(int fd, char *format, va_list ap) {
+
+  char buffer[4096] = {0};
+  int  len;
+
+  if (vsnprintf(buffer, sizeof(buffer) - 1, format, ap) < 0) { return; }
+
+  len = strnlen(buffer, sizeof(buffer));
+  IGNORED_RETURN(write(fd, buffer, len));
+
+}
+
+void seccomp_print(char *format, ...) {
+
+  va_list ap;
+  va_start(ap, format);
+  seccomp_vprint(SECCOMP_OUTPUT_FILE_FD, format, ap);
+  va_end(ap);
+
+}
+
+static void seccomp_filter_callback(struct seccomp_notif *     req,
+                                    struct seccomp_notif_resp *resp,
+                                    GumReturnAddressArray *    frames) {
+
+  GumDebugSymbolDetails details = {0};
+  if (req->data.nr == SYS_OPENAT) {
+
+    seccomp_print("SYS_OPENAT: (%s)\n", (char *)req->data.args[1]);
+
+  }
+
+  seccomp_print(
+      "\nID (%#llx) for PID %d - %d (%s) [0x%llx 0x%llx 0x%llx 0x%llx 0x%llx "
+      "0x%llx ]\n",
+      req->id, req->pid, req->data.nr, seccomp_syscall_lookup(req->data.nr),
+      req->data.args[0], req->data.args[1], req->data.args[2],
+      req->data.args[3], req->data.args[4], req->data.args[5]);
+
+  seccomp_print("FRAMES: (%u)\n", frames->len);
+  char **syms = backtrace_symbols(frames->items, frames->len);
+  if (syms == NULL) { FATAL("Failed to get symbols"); }
+
+  for (guint i = 0; i < frames->len; i++) {
+
+    if (gum_symbol_details_from_address(frames->items[i], &details)) {
+
+      seccomp_print("\t%3d. %s!%s\n", i, details.module_name,
+                    details.symbol_name);
+
+    } else {
+
+      seccomp_print("\t%3d. %s\n", i, syms[i]);
+
+    }
+
+  }
+
+  free(syms);
+
+  resp->error = 0;
+  resp->val = 0;
+  resp->id = req->id;
+  resp->flags = SECCOMP_USER_NOTIF_FLAG_CONTINUE;
+
+}
+
+static void seccomp_child(int signal_parent, void *ctx) {
+
+  int sock_fd = *((int *)ctx);
+  int fd = seccomp_socket_recv(sock_fd);
+
+  if (close(sock_fd) < 0) { FATAL("child - close"); }
+
+  seccomp_event_signal(signal_parent);
+  seccomp_filter_child_install();
+  seccomp_filter_run(fd, seccomp_filter_callback);
+
+}
+
+void seccomp_on_fork(void) {
+
+  int   sock[2] = {-1, -1};
+  pid_t child = -1;
+  int   child_fd = -1;
+
+  if (seccomp_filename == NULL) { return; }
+
+  seccomp_socket_create(sock);
+  seccomp_child_run(seccomp_child, sock, &child, &child_fd);
+
+  if (dup2(child_fd, SECCOMP_PARENT_EVENT_FD) < 0) { FATAL("dup2"); }
+
+  if (close(child_fd) < 0) { FATAL("seccomp_on_fork - close (1)"); }
+
+  if (close(sock[STDIN_FILENO]) < 0) { FATAL("grandparent - close (2)"); }
+
+  int fd = seccomp_filter_install(child);
+  seccomp_socket_send(sock[STDOUT_FILENO], fd);
+
+  if (close(sock[STDOUT_FILENO]) < 0) { FATAL("grandparent - close (3)"); }
+
+  if (close(fd) < 0) { FATAL("grandparent - close (4)"); }
+
+  seccomp_child_wait(SECCOMP_PARENT_EVENT_FD);
+
+}
+
+void seccomp_config(void) {
+
+  seccomp_filename = getenv("AFL_FRIDA_SECCOMP_FILE");
+
+}
+
+void seccomp_init(void) {
+
+  char *path = NULL;
+  int   fd;
+
+  OKF("Seccomp - file [%s]", seccomp_filename);
+
+  if (seccomp_filename == NULL) { return; }
+
+  path = g_canonicalize_filename(seccomp_filename, g_get_current_dir());
+
+  OKF("Seccomp - path [%s]", path);
+
+  fd = open(path, O_RDWR | O_CREAT | O_TRUNC,
+            S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+
+  if (dup2(fd, SECCOMP_OUTPUT_FILE_FD) < 0) {
+
+    FATAL("Failed to duplicate seccomp output file");
+
+  }
+
+  if (close(fd) < 0) { FATAL("Failed to close seccomp output file fd"); }
+
+  g_free(path);
+
+}
+