fwknop/client/utils.c

129 lines
3.1 KiB
C

/*
*****************************************************************************
*
* File: utils.c
*
* Author: Damien S. Stuart
*
* Purpose: General/Generic functions for the fwknop client.
*
* Copyright 2009-2010 Damien Stuart (dstuart@dstuart.org)
*
* License (GNU Public License):
*
* This program 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 2
* of the License, or (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
*****************************************************************************
*/
#include "common.h"
#include "fwknop_common.h"
#include "utils.h"
/* Generic hex dump function.
*/
void
hex_dump(const unsigned char *data, const int size)
{
int ln, i, j = 0;
char ascii_str[17] = {0};
for(i=0; i<size; i++)
{
if((i % 16) == 0)
{
printf(" %s\n 0x%.4x: ", ascii_str, i);
memset(ascii_str, 0x0, 17);
j = 0;
}
printf("%.2x ", data[i]);
ascii_str[j++] = (data[i] < 0x20 || data[i] > 0x7e) ? '.' : data[i];
if(j == 8)
printf(" ");
}
/* Remainder...
*/
ln = strlen(ascii_str);
if(ln > 0)
{
for(i=0; i < 16-ln; i++)
printf(" ");
printf(" %s\n\n", ascii_str);
}
}
int
verify_file_perms_ownership(const char *file)
{
int res = 1;
#if HAVE_STAT
struct stat st;
/* Every file that the fwknop client deals with should be owned
* by the user and permissions set to 600 (user read/write)
*/
if((stat(file, &st)) != 0)
{
/* if the path doesn't exist, just return, but otherwise something
* went wrong
*/
if(errno == ENOENT)
{
return 0;
} else {
fprintf(stderr, "[-] stat() against file: %s returned: %s\n",
file, strerror(errno));
exit(EXIT_FAILURE);
}
}
/* Make sure it is a regular file or symbolic link
*/
if(S_ISREG(st.st_mode) != 1 && S_ISLNK(st.st_mode) != 1)
{
fprintf(stderr,
"[-] file: %s is not a regular file or symbolic link.\n",
file
);
res = 0;
}
if((st.st_mode & (S_IRWXU|S_IRWXG|S_IRWXO)) != (S_IRUSR|S_IWUSR))
{
fprintf(stderr,
"[-] file: %s permissions should only be user read/write (0600, -rw-------)\n",
file
);
res = 0;
}
if(st.st_uid != getuid())
{
fprintf(stderr, "[-] file: %s not owned by current effective user id.\n",
file);
res = 0;
}
#endif
return res;
}
/***EOF***/