Initial commit. Filestructure, one test and logger module

4 files changed, 137 insertions, 0 deletions

diff --git a/logger/src/hook_lib/Makefile b/logger/src/hook_lib/Makefile
new file mode 100644
index 0000000..365ceee
--- /dev/null
+++ b/logger/src/hook_lib/Makefile
@@ -0,0 +1,10 @@
+file_hook.so: file_hook.o
+	ld -shared -o file_hook.so -ldl -lc file_hook.o
+
+file_hook.o: file_hook.c
+	cc -Wall -fPIC -o file_hook.o -c file_hook.c
+
+all: file_hook.so
+
+clean:
+	rm -f file_hook.o file_hook
diff --git a/logger/src/hook_lib/file_hook.c b/logger/src/hook_lib/file_hook.c
new file mode 100644
index 0000000..3bf8faf
--- /dev/null
+++ b/logger/src/hook_lib/file_hook.c
@@ -0,0 +1,111 @@
+#define _GNU_SOURCE
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+
+#include <dlfcn.h>
+
+#define _FCNTL_H
+#include <bits/fcntl.h>
+
+
+//extern int errorno;
+
+int (*_open)(const char * pathname, int flags, ...);
+int (*_open64)(const char * pathname, int flags, ...);
+
+FILE *log_file_handle;
+
+void _init() {
+  _open = (int (*)(const char * pathname, int flags, ...)) dlsym(RTLD_NEXT, "open");
+  _open64 = (int (*)(const char * pathname, int flags, ...)) dlsym(RTLD_NEXT, "open64");
+
+  if(_open==NULL || _open64==NULL) {
+	  fprintf(stderr,"Failed to load original functions of hook\n");
+	  exit(1);
+  }
+  
+  char *log_file_name=getenv("FILE_LOG");
+  if(log_file_name==NULL) {
+	fprintf(stderr,"Using stderr as output for logs "
+					"because the FILE_LOG environment variable isn't defined.\n");
+	log_file_handle=stderr;
+  } else {
+	log_file_handle=fopen(log_file_name,"a+");
+	if(log_file_handle==NULL) {
+	  fprintf(stderr,"Failed to open log file %s: %s\n", log_file_name, strerror(errno));
+	  exit(1);
+	}
+  }
+} 
+
+void _fini() {
+  fclose(log_file_handle);
+}
+
+/*
+ * Prints a string escaping spaces and '\'
+ * Does not check input variables
+*/
+void __print_escaped(FILE *fh ,const char *s){
+	for(;(*s)!=0; s++) {
+		if(*s==' ')
+		  fprintf(fh,"\\ ");
+		else if(*s=='\\')
+		  fprintf(fh,"\\\\");
+		else
+		  fprintf(fh,"%c", *s);
+	}
+}
+
+/*
+ * Format of log string: time event file flags result parents
+*/
+void __hook_log(const char *event_type, const char *filename,int flags, int result, int err) {
+
+  fprintf(log_file_handle,"%lld ",(unsigned long long)time(NULL));
+
+  __print_escaped(log_file_handle, event_type);
+  fprintf(log_file_handle," ");
+  __print_escaped(log_file_handle, filename);
+  fprintf(log_file_handle," %d %d %d", flags, result, err);
+  // TODO: add a parent processes in output
+  
+  
+  fprintf(log_file_handle,"\n");
+}
+
+int open(const char * pathname, int flags, mode_t mode) {
+    int ret;
+    if(flags & O_CREAT)
+        ret=_open(pathname, flags, mode);
+    else
+        ret=_open(pathname, flags, 0);
+
+    __hook_log("open",pathname,flags,ret,errno);
+
+	return ret;
+}
+
+int open64(const char * pathname, int flags, mode_t mode) {
+	int ret;
+	
+    if(flags & O_CREAT)
+        ret=_open64(pathname, flags, mode);
+    else
+        ret=_open64(pathname, flags, 0);
+	
+	__hook_log("open64",pathname,flags,ret,errno);
+	
+	return ret;
+}
+
+//int execve(const char *filename, char *const argv[],
+//                  char *const envp[]) {
+  //printf("FORK!!!!(canceled)");
+//  return NULL;
+//}
diff --git a/logger/test/1_access/Makefile b/logger/test/1_access/Makefile
new file mode 100644
index 0000000..b3ea345
--- /dev/null
+++ b/logger/test/1_access/Makefile
@@ -0,0 +1,6 @@
+accesser: accesser.c
+
+all: accesser
+
+clean:
+	rm -f accesser
\ No newline at end of file
diff --git a/logger/test/1_access/accesser.c b/logger/test/1_access/accesser.c
new file mode 100644
index 0000000..912fc70
--- /dev/null
+++ b/logger/test/1_access/accesser.c
@@ -0,0 +1,10 @@
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+int main(int argc, char **argv) {
+  if(argc<=1) {
+	printf("Usage: accesser.c <file1> [file2] [file3] ...\n");
+  }
+  return 0; 
+}