Files
2024-09-12 22:24:27 -06:00

236 lines
6.8 KiB
Diff

--- src/rm.c.orig Sat Nov 23 23:11:12 1996
+++ src/rm.c Sun Jan 24 13:37:20 1999
@@ -1,3 +1,10 @@
+/* patch for rm from fileutils-3.16 to support secure data deletion
+ * to be activated by -s. -sss gives full erasure security (38 overwrites)
+ * This patch is from the secure_delete-2.0.tar.gz package available
+ * at http://www.thehackerschoice.com - get it, and read the documentation!
+ * (c)1999 by van Hauser / [THC] - The Hacker's Choice, vh@reptile.rug.ac.be
+ */
+
/* `rm' file deletion utility for GNU.
Copyright (C) 88, 90, 91, 94, 95, 1996 Free Software Foundation, Inc.
@@ -21,6 +28,11 @@
#include <stdio.h>
#include <getopt.h>
#include <sys/types.h>
+/* SRM BEGIN */
+#include <sys/stat.h>
+#include <unistd.h>
+#include <stdlib.h>
+/* SRM END */
#include "system.h"
#include "error.h"
@@ -50,6 +62,14 @@
int yesno ();
void strip_trailing_slashes ();
+/* SRM BEGIN */
+#define BLOCKSIZE 32769
+#define DIR_SEPERATOR '/'
+#define FLUSH sync()
+#define RANDOM_DEVICE "/dev/urandom"
+/* SRM END */
+
+static int secure_delete ();
static int clear_directory __P ((struct stat *statp));
static int duplicate_entry __P ((struct pathstack *stack, ino_t inum));
static int remove_dir __P ((struct stat *statp));
@@ -68,6 +88,12 @@
/* Path of file now being processed; extended as necessary. */
static char *pathname;
+/* SRM BEGIN */
+static int secure; /* secure overwrite mode */
+static char fillbuf[BLOCKSIZE];
+static FILE *devrandom;
+/* SRM END */
+
/* Number of bytes currently allocated for `pathname';
made larger when necessary, but never smaller. */
static int pnsize;
@@ -104,6 +130,9 @@
{"force", no_argument, NULL, 'f'},
{"interactive", no_argument, NULL, 'i'},
{"recursive", no_argument, &recursive, 1},
+/* SRM BEGIN */
+ {"secure_delete", no_argument, NULL, 's'},
+/* SRM END */
{"verbose", no_argument, &verbose, 1},
{"help", no_argument, &show_help, 1},
{"version", no_argument, &show_version, 1},
@@ -125,8 +154,8 @@
= unlink_dirs = 0;
pnsize = 256;
pathname = xmalloc (pnsize);
-
- while ((c = getopt_long (argc, argv, "dfirvR", long_opts, (int *) 0)) != EOF)
+
+ while ((c = getopt_long (argc, argv, "dfirsvR", long_opts, (int *) 0)) != EOF)
{
switch (c)
{
@@ -147,6 +176,11 @@
case 'R':
recursive = 1;
break;
+/* SRM BEGIN */
+ case 's':
+ secure++;
+ break;
+/* SRM END */
case 'v':
verbose = 1;
break;
@@ -198,6 +232,116 @@
exit (err > 0);
}
+/* SRM BEGIN */
+
+void fill_buf(char pattern[3]) {
+ int loop;
+ int where;
+ for (loop = 0; loop < (BLOCKSIZE / 3); loop++) {
+ where = loop * 3;
+ fillbuf[where] = pattern[0];
+ fillbuf[where+1] = pattern[1];
+ fillbuf[where+2] = pattern[2];
+ }
+}
+void random_buf() {
+ int loop;
+ if (devrandom != NULL)
+ for (loop = 0; loop < BLOCKSIZE; loop++)
+ fillbuf[loop] = (unsigned char) (256.0*rand()/(RAND_MAX+1.0));
+ else
+ fread(&fillbuf, BLOCKSIZE, 1, devrandom);
+}
+
+/* overwriting the file several times */
+
+ static int
+ secure_delete (delfile)
+ char *delfile;
+ {
+ unsigned char write_modes[27][3] = {
+ {"\x55\x55\x55"}, {"\xaa\xaa\xaa"}, {"\x92\x49\x24"}, {"\x49\x24\x92"},
+ {"\x24\x92\x49"}, {"\x00\x00\x00"}, {"\x11\x11\x11"}, {"\x22\x22\x22"},
+ {"\x33\x33\x33"}, {"\x44\x44\x44"}, {"\x55\x55\x55"}, {"\x66\x66\x66"},
+ {"\x77\x77\x77"}, {"\x88\x88\x88"}, {"\x99\x99\x99"}, {"\xaa\xaa\xaa"},
+ {"\xbb\xbb\xbb"}, {"\xcc\xcc\xcc"}, {"\xdd\xdd\xdd"}, {"\xee\xee\xee"},
+ {"\xff\xff\xff"}, {"\x92\x49\x24"}, {"\x49\x24\x92"}, {"\x24\x92\x49"},
+ {"\x6d\xb6\xdb"}, {"\xb6\xdb\x6d"}, {"\xdb\x6d\xb6"}
+ };
+ unsigned char std_array[3] = "\xff\xff\xff";
+ FILE *f;
+ int file;
+ unsigned long writes;
+ unsigned long counter;
+ unsigned long filesize;
+ struct stat filestat;
+ int turn;
+ int result;
+ unsigned char ch;
+ char newname[512];
+
+/* open the file, get the filesize, calculate the numbers of needed writings */
+ if (lstat(delfile, &filestat))
+ return 1;
+ if (! S_ISREG(filestat.st_mode))
+ return 1;
+ if ((f = fopen(delfile, "r+b")) == NULL)
+ return 1;
+ filesize = filestat.st_size;
+ writes = (1 + (filesize / BLOCKSIZE));
+ file=fileno(f);
+ (void) setvbuf(stdout, NULL, _IONBF, 0);
+ devrandom = fopen(RANDOM_DEVICE, "r");
+
+ if (verbose)
+ printf(" ");
+
+
+ if (secure > 1) {
+ fill_buf(std_array);
+ for (counter=1; counter<=writes; counter++)
+ fwrite(&fillbuf, 1, BLOCKSIZE, f);
+ if (verbose)
+ printf("*");
+ fflush(f);
+ fsync(file);
+ }
+
+/* do the overwriting stuff */
+ for (turn=0; turn<=36; turn++) {
+ rewind(f);
+ if ((secure < 3) && (turn > 0)) break;
+ if ((turn>=5) && (turn<=31)) {
+ fill_buf(write_modes[turn-5]);
+ for (counter=1; counter<=writes; counter++)
+ fwrite(&fillbuf, 1, BLOCKSIZE, f);
+ } else {
+ for (counter=1; counter<=writes; counter++) {
+ random_buf();
+ fwrite(&fillbuf, 1, BLOCKSIZE, f);
+ }
+ }
+ fflush(f);
+ if (fsync(file) < 0)
+ FLUSH;
+ if (verbose)
+ printf("*");
+ }
+ (void) fclose(f);
+ (void) fclose(devrandom);
+/* Hard Flush -> Force cached data to be written to disk */
+ FLUSH;
+/* open + truncating the file, so an attacker doesn't know the diskblocks */
+ if ((file = open(delfile, O_WRONLY | O_TRUNC)) >= 0)
+ close(file);
+ if (verbose)
+ printf(" wiped\n");
+ return 0;
+}
+
+/* SRM END */
+
/* Remove file or directory `pathname' after checking appropriate things.
Return 0 if `pathname' is removed, 1 if not. */
@@ -264,8 +408,16 @@
return 1;
}
- if (verbose)
- printf ("%s\n", pathname);
+ if (verbose) {
+ printf ("%s", pathname);
+ if (secure == 0)
+ printf ("\n");
+ }
+
+/* SRM BEGIN */
+ if (secure)
+ secure_delete(pathname);
+/* SRM END */
if (unlink (pathname) && (errno != ENOENT || !ignore_missing_files))
{
@@ -536,11 +688,13 @@
-f, --force ignore nonexistent files, never prompt\n\
-i, --interactive prompt before any removal\n\
-r, -R, --recursive remove the contents of directories recursively\n\
+ -s, --secure_delete secure overwrite (-sss for full security)\n\
-v, --verbose explain what is being done\n\
--help display this help and exit\n\
--version output version information and exit\n\
"));
puts (_("\nReport bugs to fileutils-bugs@gnu.ai.mit.edu"));
+ puts (_("\nWith secure_delete patch by van Hauser <vh@reptile.rug.ac.be>"));
}
exit (status);
}