Initial implementation of the ptrace wrapper

2 files changed, 63 insertions, 0 deletions

diff --git a/wrapper/Makefile b/wrapper/Makefile
new file mode 100644
index 0000000..1019833
--- /dev/null
+++ b/wrapper/Makefile
@@ -0,0 +1,12 @@
+CC := gcc
+
+CFLAGS = -Wall -Wextra -Os -std=c99 -pedantic -fstack-protector-all
+CFLAGS += $(USER_CFLAGS)
+
+LDFLAGS = -shared
+LDFLAGS += $(USER_LDFLAGS)
+
+all: libptracew.so
+
+libtestw.so: ptrace.c
+	$(CC) $(CFLAGS) $^ -o $@ $(LDFLAGS)
diff --git a/wrapper/ptrace.c b/wrapper/ptrace.c
new file mode 100644
index 0000000..3ce42a1
--- /dev/null
+++ b/wrapper/ptrace.c
@@ -0,0 +1,51 @@
+/* Copyright (C) 2017 Jakob Kreuze, All Rights Reserved.
+
+   This file is part of Hypodermic.
+
+   Hypodermic 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 3 of the License, or (at
+   your option) any later version.
+
+   Hypodermic 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 Hypodermic. If not, see <http://www.gnu.org/licenses/>. */
+
+#include <sys/ptrace.h>
+#include <sys/wait.h>
+
+#include <stddef.h>
+
+
+int attach(int pid) {
+    if ((ptrace(PTRACE_ATTACH, pid, NULL, NULL)) < 0) {
+        return -1;
+    }
+
+    waitpid(pid, NULL, WUNTRACED);
+    return 0;
+}
+
+
+int detach(int pid) {
+    return ptrace(PTRACE_DETACH, pid, NULL, NULL) < 0;
+}
+
+
+int cont(int pid) {
+    int s;
+
+    if ((ptrace(PTRACE_CONT, pid, NULL, NULL)) < 0) {
+        return -1;
+    }
+
+    while (!WIFSTOPPED(s)) {
+        waitpid(pid, &s, WNOHANG);
+    }
+
+    return 0;
+}