From 4a3429a96b5b5ea7468540349aeb4535d5738053 Mon Sep 17 00:00:00 2001
From: the lemons <citrons@mondecitronne.com>
Date: Tue, 7 Feb 2023 22:43:58 -0600
Subject: create evilizer

---
 Makefile  |  2 ++
 evilize.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 evilize.c

diff --git a/Makefile b/Makefile
index 4345b7e..903b7e9 100644
--- a/Makefile
+++ b/Makefile
@@ -12,6 +12,8 @@ core.c: procfs.h memview.h
 memview.c: procfs.h memview.h
 procfs.c: procfs.h
 
+evilize: evilize.o
+
 .SUFFIXES: .c .o
 .c.o:
 	$(CC) $(CFLAGS) -c -o $@ $<
diff --git a/evilize.c b/evilize.c
new file mode 100644
index 0000000..e3b13aa
--- /dev/null
+++ b/evilize.c
@@ -0,0 +1,65 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <signal.h>
+#include <sys/ptrace.h>
+
+#define ERRCHECK(E)\
+	if ((E) == -1) {perror(argv[0]); kill(pid, SIGHUP); return -1;}
+
+int main(int argc, char *argv[]) {
+	if (argc < 2) {
+		fprintf(stderr, "usage: %s COMMAND [ARGS]...\n" , argv[0]);
+		return -1;
+	}
+	pid_t pid = fork();
+	if (pid == -1) {
+		perror(argv[0]);
+		return -1;
+	}
+	if (pid == 0) {
+		ptrace(PTRACE_TRACEME, 0, NULL, NULL);
+		raise(SIGSTOP);
+		if (execvp(argv[1], argv + 1) == -1) {
+			perror(argv[0]);
+			return -1;
+		}
+	} else {
+		ERRCHECK(ptrace(PTRACE_ATTACH, pid, NULL, NULL));
+		int status;
+		pid_t w = waitpid(pid, &status, __WALL);
+		ERRCHECK(w);
+		ERRCHECK(ptrace(PTRACE_CONT, pid, NULL, NULL));
+		while (1) {
+			pid_t w = waitpid(pid, &status, __WALL);
+			ERRCHECK(w);
+			if (WIFEXITED(status))
+				return WEXITSTATUS(status);
+			if (WIFSTOPPED(status)) {
+				if (WIFSIGNALED(status)) {
+					errno = 0;
+					switch (WSTOPSIG(status)) {
+						case SIGABRT:
+						case SIGBUS:
+						case SIGFPE:
+						case SIGILL:
+						case SIGSEGV:
+							ptrace(PTRACE_CONT, pid, NULL, NULL);
+							break;
+						default:
+							ptrace(PTRACE_CONT, pid, NULL, WSTOPSIG(status));
+							break;
+					}
+					if (errno && errno != ESRCH) {
+						perror("ptrace");
+						kill(pid, SIGHUP);
+						return -1;
+					}
+				} else ptrace(PTRACE_CONT, pid, NULL, NULL);
+			}
+		}
+	}
+}
-- 
cgit v1.2.3