From 5837f17e9368553bf13f094e0e62d8d38edf6589 Mon Sep 17 00:00:00 2001
From: Tomas Mudrunka <tomas@mudrunka.cz>
Date: Tue, 11 Feb 2014 03:28:06 +0100
Subject: [PATCH] Troll23 test

---
 c/troll23/Makefile   |  9 +++++++++
 c/troll23/sshkeys.sh |  5 +++++
 c/troll23/test.c     |  4 ++++
 c/troll23/troll23.c  | 47 ++++++++++++++++++++++++++++++++++++++++----
 4 files changed, 61 insertions(+), 4 deletions(-)
 create mode 100755 c/troll23/sshkeys.sh

diff --git a/c/troll23/Makefile b/c/troll23/Makefile
index d09d74f..c1d53dc 100644
--- a/c/troll23/Makefile
+++ b/c/troll23/Makefile
@@ -6,3 +6,12 @@ $(proj).so: $(proj).c
 	# To test:
 	# export LD_PRELOAD=$(PWD)/$@
 	# touch /tmp/deleteme; rm /tmp/deleteme
+	# Or:
+	# make go
+	# make ssh
+
+go: test $(proj).so
+	LD_PRELOAD=$(PWD)/$(proj).so ./test
+
+ssh: $(proj).so
+	LD_PRELOAD=$(PWD)/$(proj).so ./sshkeys.sh
diff --git a/c/troll23/sshkeys.sh b/c/troll23/sshkeys.sh
new file mode 100755
index 0000000..cd0f5e6
--- /dev/null
+++ b/c/troll23/sshkeys.sh
@@ -0,0 +1,5 @@
+#!/bin/sh
+ssh-keygen -P '' -f ssh-a.key >/dev/null
+ssh-keygen -P '' -f ssh-b.key >/dev/null
+md5sum ssh-?.key ssh-?.key.pub
+rm ssh-?.key ssh-?.key.pub
diff --git a/c/troll23/test.c b/c/troll23/test.c
index 32cda63..a529f5b 100644
--- a/c/troll23/test.c
+++ b/c/troll23/test.c
@@ -1,3 +1,7 @@
+#include <stdio.h>
+
 int main() {
+	srand(time(NULL));
 	printf("%d\n", rand());
+	return(0);
 }
diff --git a/c/troll23/troll23.c b/c/troll23/troll23.c
index 5ff84e1..f1822e0 100644
--- a/c/troll23/troll23.c
+++ b/c/troll23/troll23.c
@@ -1,21 +1,35 @@
 #define _GNU_SOURCE
+#include <stdlib.h>
 #include <stdio.h>
 #include <sys/types.h>
+#include <sys/syscall.h>
 #include <dlfcn.h>
 #include <stdarg.h>
+#include <time.h>
 
-int rand(void) { 	return 23; }
-int random(void) { 	return 23; }
+//Catch rand() calls etc...
+time_t time(time_t *tloc) { srand(23); return (time_t)0; }
+int rand(void) {	srand(23); return 23; }
+long int random(void) {	srand(23); return 23; }
+int rand_r(unsigned int *seedp) { srand(23); return 23; }
+int random_r(struct random_data *buf, int32_t *result) { srand(23); return 23; }
 
+//Catch open() calls (while redirecting filename):
 static const char *redirect_name(const char *name)
 {
-	if(strcmp(name,"/dev/random") == 0) return "/dev/zero";
-	if(strcmp(name,"/dev/urandom") == 0) return "/dev/zero";
+	if(
+		(strcmp(name,"/dev/random") == 0) ||
+		(strcmp(name,"/dev/urandom") == 0)
+	) {
+		printf("REDIRECT HIT: %s\n", name);
+		return "/dev/zero";
+	}
 	return name;
 }
 
 int open(const char *filename, int flags, ...)
 {
+	//srand(23);
 	static int (*open_orig)(const char *, int, mode_t);
 	int ret;
 	va_list ap;
@@ -30,8 +44,33 @@ int open(const char *filename, int flags, ...)
 	va_end(ap);
 
 	ret = open_orig(redirect_name(filename), flags, mode);
+	//ret = syscall(SYS_open,redirect_name(filename),flags,mode);
 
 	printf("open(\"%s\", 0x%x, %o) -> %d\n", filename, flags, mode, ret);
 
 	return ret;
 }
+
+int open64(const char *filename, int flags, ...)
+{
+	//srand(23);
+	static int (*open64_orig)(const char *, int, mode_t);
+	int ret;
+	va_list ap;
+	mode_t mode;
+
+	if (!open64_orig) {
+		open64_orig = dlsym(RTLD_NEXT, "open64");
+	}
+
+	va_start(ap, flags);
+	mode = va_arg(ap, mode_t);
+	va_end(ap);
+
+	ret = open64_orig(redirect_name(filename), flags, mode);
+	//ret = syscall(SYS_open64,redirect_name(filename),flags,mode);
+
+	printf("open64(\"%s\", 0x%x, %o) -> %d\n", filename, flags, mode, ret);
+
+	return ret;
+}
-- 
2.30.2