New file rotormodule.c (by Lance Ellinghouse).
diff --git a/Modules/rotormodule.c b/Modules/rotormodule.c
new file mode 100644
index 0000000..2950a93
--- /dev/null
+++ b/Modules/rotormodule.c
@@ -0,0 +1,735 @@
+/***********************************************************
+Copyright 1992 by Lance Ellinghouse (lance@markv.com).
+
+Copyright 1991, 1992 by Stichting Mathematisch Centrum, Amsterdam, The
+Netherlands.
+
+ All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the names of Stichting Mathematisch
+Centrum or CWI not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
+THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
+FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+******************************************************************/
+
+/* This creates an encryption and decryption engine I am calling
+ a rotor due to the original design was a harware rotor with
+ contacts used in Germany during WWII.
+
+Rotor Module:
+
+- rotor.newrotor('key') -> rotorobject (default of 6 rotors)
+- rotor.newrotor('key', num_rotors) -> rotorobject
+
+Rotor Objects:
+
+- ro.encrypt('string') -> encrypted string
+- ro.decrypt('encrypted string') -> unencrypted string
+
+NOTE: you MUST use the SAME key in rotor.newrotor()
+ if you wish to decrypt an encrypted string.
+ Also, the encrypted string is NOT 0-127 ASCII.
+ It is considered BINARY data.
+
+*/
+
+/* Rotor objects */
+
+#include "allobjects.h"
+#include "modsupport.h"
+#include <stdio.h>
+#include <math.h>
+
+typedef struct {
+ OB_HEAD
+ int seed[3];
+ short key[5];
+ int size;
+ int size_mask;
+ int rotors;
+ unsigned char *e_rotor; /* [num_rotors][size] */
+ unsigned char *d_rotor; /* [num_rotors][size] */
+ unsigned char *positions; /* [num_rotors] */
+ unsigned char *advances; /* [num_rotors] */
+} rotorobject;
+
+extern typeobject Rotortype; /* Really static, forward */
+
+#define is_rotorobject(v) ((v)->ob_type == &Rotortype)
+
+/*
+ This defines the necessary routines to manage rotor objects
+*/
+
+static void set_seed( r )
+rotorobject *r;
+{
+ r->seed[0] = r->key[0];
+ r->seed[1] = r->key[1];
+ r->seed[2] = r->key[2];
+}
+
+/* Return the next random number in the range [0.0 .. 1.0) */
+static float r_random( r )
+rotorobject *r;
+{
+ int x, y, z;
+ float val, term;
+
+ x = r->seed[0];
+ y = r->seed[1];
+ z = r->seed[2];
+
+ x = 171 * (x % 177) - 2 * (x/177);
+ y = 172 * (y % 176) - 35 * (y/176);
+ z = 170 * (z % 178) - 63 * (z/178);
+
+ if (x < 0) x = x + 30269;
+ if (y < 0) y = y + 30307;
+ if (z < 0) z = z + 30323;
+
+ r->seed[0] = x;
+ r->seed[1] = y;
+ r->seed[2] = z;
+
+ term = (float)(
+ (((float)x)/(float)30269.0) +
+ (((float)y)/(float)30307.0) +
+ (((float)z)/(float)30323.0)
+ );
+ val = term - (float)floor((double)term);
+
+ if (val >= 1.0) val = 0.0;
+
+ return val;
+}
+
+static short r_rand(r,s)
+rotorobject *r;
+short s;
+{
+ short tmp = (short)((short)(r_random(r) * (float)s) % s);
+ return tmp;
+}
+
+static void set_key(r, key)
+rotorobject *r;
+char *key;
+{
+ int k1=995, k2=576, k3=767, k4=671, k5=463;
+ int i;
+ int len=strlen(key);
+ for (i=0;i<len;i++) {
+ k1 = (((k1<<3 | k1<<-13) + key[i]) & 65535);
+ k2 = (((k2<<3 | k2<<-13) ^ key[i]) & 65535);
+ k3 = (((k3<<3 | k3<<-13) - key[i]) & 65535);
+ k4 = ((key[i] - (k4<<3 | k4<<-13)) & 65535);
+ k5 = (((k5<<3 | k5<<-13) ^ ~key[i]) & 65535);
+ }
+ r->key[0] = (short)k1;
+ r->key[1] = (short)(k2|1);
+ r->key[2] = (short)k3;
+ r->key[3] = (short)k4;
+ r->key[4] = (short)k5;
+
+ set_seed(r);
+}
+
+/* These define the interface to a rotor object */
+static rotorobject *
+newrotorobject(num_rotors, key)
+ int num_rotors;
+ char *key;
+{
+ rotorobject *xp;
+ xp = NEWOBJ(rotorobject, &Rotortype);
+ if (xp == NULL)
+ return NULL;
+ set_key(xp,key);
+
+ xp->size = 256;
+ xp->size_mask = xp->size - 1;
+ xp->size_mask = 0;
+ xp->rotors = num_rotors;
+
+ xp->e_rotor = (unsigned char *)malloc((num_rotors * (xp->size * sizeof(char))));
+ if (xp->e_rotor == (unsigned char *)NULL) {
+ err_nomem();
+ DEL(xp);
+ xp = (object *)NULL;
+ goto done;
+ }
+ xp->d_rotor = (unsigned char *)malloc((num_rotors * (xp->size * sizeof(char))));
+ if (xp->d_rotor == (unsigned char *)NULL) {
+ err_nomem();
+ free(xp->e_rotor);
+ DEL(xp);
+ xp = (object *)NULL;
+ goto done;
+ }
+ xp->positions = (unsigned char *)malloc(num_rotors * sizeof(char));
+ if (xp->positions == (unsigned char *)NULL) {
+ err_nomem();
+ free(xp->e_rotor);
+ free(xp->d_rotor);
+ DEL(xp);
+ xp = (object *)NULL;
+ goto done;
+ }
+ xp->advances = (unsigned char *)malloc(num_rotors * sizeof(char));
+ if (xp->advances == (unsigned char *)NULL) {
+ err_nomem();
+ free(xp->e_rotor);
+ free(xp->d_rotor);
+ free(xp->positions);
+ DEL(xp);
+ xp = (object *)NULL;
+ goto done;
+ }
+done:
+ return xp;
+}
+
+/* These routines impliment the rotor itself */
+
+/* Here is a fairly sofisticated {en,de}cryption system. It is bassed
+on the idea of a "rotor" machine. A bunch of rotors, each with a
+different permutation of the alphabet, rotate around a different
+amount after encrypting one character. The current state of the
+rotors is used to encrypt one character.
+
+ The code is smart enought to tell if your alphabet has a number of
+characters equal to a power of two. If it does, it uses logical
+operations, if not it uses div and mod (both require a division).
+
+ You will need to make two changes to the code 1) convert to c, and
+customize for an alphabet of 255 chars 2) add a filter at the
+begining, and end, which subtracts one on the way in, and adds one on
+the way out.
+
+ You might wish to do some timing studies. Another viable
+alternative is to "byte stuff" the encrypted data of a normal (perhaps
+this one) encryption routine.
+
+j'
+*/
+
+/*(defun RTR-make-id-rotor (rotor)
+ "Set ROTOR to the identity permutation"
+ (let ((j 0))
+ (while (< j RTR-size)
+ (aset rotor j j)
+ (setq j (+ 1 j)))
+ rotor))*/
+static void RTR_make_id_rotor(r, rtr)
+ rotorobject *r;
+ unsigned char *rtr;
+{
+ register int j;
+ register int size = r->size;
+ for (j=0;j<size;j++) {
+ rtr[j] = (unsigned char)j;
+ }
+}
+
+
+/*(defvar RTR-e-rotors
+ (let ((rv (make-vector RTR-number-of-rotors 0))
+ (i 0)
+ tr)
+ (while (< i RTR-number-of-rotors)
+ (setq tr (make-vector RTR-size 0))
+ (RTR-make-id-rotor tr)
+ (aset rv i tr)
+ (setq i (+ 1 i)))
+ rv)
+ "The current set of encryption rotors")*/
+static void RTR_e_rotors(r)
+ rotorobject *r;
+{
+ int i;
+ for (i=0;i<r->rotors;i++) {
+ RTR_make_id_rotor(r,&(r->e_rotor[(i*r->size)]));
+ }
+}
+
+/*(defvar RTR-d-rotors
+ (let ((rv (make-vector RTR-number-of-rotors 0))
+ (i 0)
+ tr)
+ (while (< i RTR-number-of-rotors)
+ (setq tr (make-vector RTR-size 0))
+ (setq j 0)
+ (while (< j RTR-size)
+ (aset tr j j)
+ (setq j (+ 1 j)))
+ (aset rv i tr)
+ (setq i (+ 1 i)))
+ rv)
+ "The current set of decryption rotors")*/
+static void RTR_d_rotors(r)
+ rotorobject *r;
+{
+ register int i, j;
+ for (i=0;i<r->rotors;i++) {
+ for (j=0;j<r->size;j++) {
+ r->d_rotor[((i*r->size)+j)] = (unsigned char)j;
+ }
+ }
+}
+
+/*(defvar RTR-positions (make-vector RTR-number-of-rotors 1)
+ "The positions of the rotors at this time")*/
+static void RTR_positions(r)
+ rotorobject *r;
+{
+ int i;
+ for (i=0;i<r->rotors;i++) {
+ r->positions[i] = 1;
+ }
+}
+
+/*(defvar RTR-advances (make-vector RTR-number-of-rotors 1)
+ "The number of positions to advance the rotors at a time")*/
+static void RTR_advances(r)
+ rotorobject *r;
+{
+ int i;
+ for (i=0;i<r->rotors;i++) {
+ r->advances[i] = 1;
+ }
+}
+
+/*(defun RTR-permute-rotor (e d)
+ "Permute the E rotor, and make the D rotor its inverse"
+ ;; see Knuth for explaination of algorythm.
+ (RTR-make-id-rotor e)
+ (let ((i RTR-size)
+ q j)
+ (while (<= 2 i)
+ (setq q (fair16 i)) ; a little tricky, decrement here
+ (setq i (- i 1)) ; since we have origin 0 array's
+ (setq j (aref e q))
+ (aset e q (aref e i))
+ (aset e i j)
+ (aset d j i))
+ (aset e 0 (aref e 0)) ; don't forget e[0] and d[0]
+ (aset d (aref e 0) 0)))*/
+static void RTR_permute_rotor(r, e, d)
+ rotorobject *r;
+ unsigned char *e;
+ unsigned char *d;
+{
+ short i = r->size;
+ short q;
+ unsigned char j;
+ RTR_make_id_rotor(r,e);
+ while (2 <= i) {
+ q = r_rand(r,i);
+ i--;
+ j = e[q];
+ e[q] = (unsigned char)e[i];
+ e[i] = (unsigned char)j;
+ d[j] = (unsigned char)i;
+ }
+ e[0] = (unsigned char)e[0];
+ d[(e[0])] = (unsigned char)0;
+}
+
+/*(defun RTR-init (key)
+ "Given KEY (a list of 5 16 bit numbers), initialize the rotor machine.
+Set the advancement, position, and permutation of the rotors"
+ (R16-set-state key)
+ (let (i)
+ (setq i 0)
+ (while (< i RTR-number-of-rotors)
+ (aset RTR-positions i (fair16 RTR-size))
+ (aset RTR-advances i (+ 1 (* 2 (fair16 (/ RTR-size 2)))))
+ (message "Initializing rotor %d..." i)
+ (RTR-permute-rotor (aref RTR-e-rotors i) (aref RTR-d-rotors i))
+ (setq i (+ 1 i)))))*/
+static void RTR_init(r)
+ rotorobject *r;
+{
+ int i;
+ set_seed(r);
+ RTR_positions(r);
+ RTR_advances(r);
+ RTR_e_rotors(r);
+ RTR_d_rotors(r);
+ for(i=0;i<r->rotors;i++) {
+ r->positions[i] = r_rand(r,r->size);
+ r->advances[i] = (1+(2*(r_rand(r,r->size/2))));
+ RTR_permute_rotor(r,&(r->e_rotor[(i*r->size)]),&(r->d_rotor[(i*r->size)]));
+ }
+}
+
+/*(defun RTR-advance ()
+ "Change the RTR-positions vector, using the RTR-advances vector"
+ (let ((i 0)
+ (temp 0))
+ (if RTR-size-mask
+ (while (< i RTR-number-of-rotors)
+ (setq temp (+ (aref RTR-positions i) (aref RTR-advances i)))
+ (aset RTR-positions i (logand temp RTR-size-mask))
+ (if (and (>= temp RTR-size)
+ (< i (- RTR-number-of-rotors 1)))
+ (aset RTR-positions (+ i 1)
+ (+ 1 (aref RTR-positions (+ i 1)))))
+ (setq i (+ i 1)))
+ (while (< i RTR-number-of-rotors)
+ (setq temp (+ (aref RTR-positions i) (aref RTR-advances i)))
+ (aset RTR-positions i (% temp RTR-size))
+ (if (and (>= temp RTR-size)
+ (< i (- RTR-number-of-rotors 1)))
+ (aset RTR-positions (+ i 1)
+ (+ 1 (aref RTR-positions (+ i 1)))))
+ (setq i (+ i 1))))))*/
+static void RTR_advance(r)
+ rotorobject *r;
+{
+ register int i=0, temp=0;
+ if (r->size_mask) {
+ while (i<r->rotors) {
+ temp = r->positions[i] + r->advances[i];
+ r->positions[i] = temp & r->size_mask;
+ if ((temp >= r->size) && (i < (r->rotors - 1))) {
+ r->positions[(i+1)] = 1 + r->positions[(i+1)];
+ }
+ i++;
+ }
+ } else {
+ while (i<r->rotors) {
+ temp = r->positions[i] + r->advances[i];
+ r->positions[i] = temp%r->size;
+ if ((temp >= r->size) && (i < (r->rotors - 1))) {
+ r->positions[(i+1)] = 1 + r->positions[(i+1)];
+ }
+ i++;
+ }
+ }
+}
+
+/*(defun RTR-e-char (p)
+ "Encrypt the character P with the current rotor machine"
+ (let ((i 0))
+ (if RTR-size-mask
+ (while (< i RTR-number-of-rotors)
+ (setq p (aref (aref RTR-e-rotors i)
+ (logand (logxor (aref RTR-positions i)
+ p)
+ RTR-size-mask)))
+ (setq i (+ 1 i)))
+ (while (< i RTR-number-of-rotors)
+ (setq p (aref (aref RTR-e-rotors i)
+ (% (logxor (aref RTR-positions i)
+ p)
+ RTR-size)))
+ (setq i (+ 1 i))))
+ (RTR-advance)
+ p))*/
+static unsigned char RTR_e_char(r, p)
+ rotorobject *r;
+ unsigned char p;
+{
+ register int i=0;
+ register unsigned char tp=p;
+ if (r->size_mask) {
+ while (i < r->rotors) {
+ tp = r->e_rotor[(i*r->size)+(((r->positions[i] ^ tp) & r->size_mask))];
+ i++;
+ }
+ } else {
+ while (i < r->rotors) {
+ tp = r->e_rotor[(i*r->size)+(((r->positions[i] ^ tp) % r->size))];
+ i++;
+ }
+ }
+ RTR_advance(r);
+ return ((unsigned char)tp);
+}
+
+/*(defun RTR-d-char (c)
+ "Decrypt the character C with the current rotor machine"
+ (let ((i (- RTR-number-of-rotors 1)))
+ (if RTR-size-mask
+ (while (<= 0 i)
+ (setq c (logand (logxor (aref RTR-positions i)
+ (aref (aref RTR-d-rotors i)
+ c))
+ RTR-size-mask))
+ (setq i (- i 1)))
+ (while (<= 0 i)
+ (setq c (% (logxor (aref RTR-positions i)
+ (aref (aref RTR-d-rotors i)
+ c))
+ RTR-size))
+ (setq i (- i 1))))
+ (RTR-advance)
+ c))*/
+static unsigned char RTR_d_char(r, c)
+ rotorobject *r;
+ unsigned char c;
+{
+ register int i=r->rotors - 1;
+ register unsigned char tc=c;
+ if (r->size_mask) {
+ while (0 <= i) {
+ tc = (r->positions[i] ^ r->d_rotor[(i*r->size)+tc]) & r->size_mask;
+ i--;
+ }
+ } else {
+ while (0 <= i) {
+ tc = (r->positions[i] ^ r->d_rotor[(i*r->size)+tc]) % r->size;
+ i--;
+ }
+ }
+ RTR_advance(r);
+ return(tc);
+}
+
+/*(defun RTR-e-region (beg end key)
+ "Perform a rotor encryption of the region from BEG to END by KEY"
+ (save-excursion
+ (let ((tenth (/ (- end beg) 10)))
+ (RTR-init key)
+ (goto-char beg)
+ ;; ### make it stop evry 10% or so to tell us
+ (while (< (point) end)
+ (let ((fc (following-char)))
+ (insert-char (RTR-e-char fc) 1)
+ (delete-char 1))))))*/
+static void RTR_e_region(r, beg, len)
+ rotorobject *r;
+ unsigned char *beg;
+ int len;
+{
+ register int i;
+ RTR_init(r);
+ for (i=0;i<len;i++) {
+ beg[i]=RTR_e_char(r,beg[i]);
+ }
+}
+
+/*(defun RTR-d-region (beg end key)
+ "Perform a rotor decryption of the region from BEG to END by KEY"
+ (save-excursion
+ (progn
+ (RTR-init key)
+ (goto-char beg)
+ (while (< (point) end)
+ (let ((fc (following-char)))
+ (insert-char (RTR-d-char fc) 1)
+ (delete-char 1))))))*/
+void static RTR_d_region(r, beg, len)
+ rotorobject *r;
+ unsigned char *beg;
+ int len;
+{
+ register int i;
+ RTR_init(r);
+ for (i=0;i<len;i++) {
+ beg[i]=RTR_d_char(r,beg[i]);
+ }
+}
+
+
+/*(defun RTR-key-string-to-ints (key)
+ "Convert a string into a list of 4 numbers"
+ (let ((k1 995)
+ (k2 576)
+ (k3 767)
+ (k4 671)
+ (k5 463)
+ (i 0))
+ (while (< i (length key))
+ (setq k1 (logand (+ (logior (lsh k1 3) (lsh k1 -13)) (aref key i)) 65535))
+ (setq k2 (logand (logxor (logior (lsh k2 3) (lsh k2 -13)) (aref key i)) 65535))
+ (setq k3 (logand (- (logior (lsh k3 3) (lsh k3 -13)) (aref key i)) 65535))
+ (setq k4 (logand (- (aref key i) (logior (lsh k4 3) (lsh k4 -13))) 65535))
+ (setq k5 (logand (logxor (logior (lsh k5 3) (lsh k5 -13)) (lognot (aref key i))) 65535))
+ (setq i (+ i 1)))
+ (list k1 (logior 1 k2) k3 k4 k5)))*/
+/* This is done in set_key() above */
+
+/*(defun encrypt-region (beg end key)
+ "Interactivly encrypt the region"
+ (interactive "r\nsKey:")
+ (RTR-e-region beg end (RTR-key-string-to-ints key)))*/
+static void encrypt_region(r, region, len)
+ rotorobject *r;
+ unsigned char *region;
+ int len;
+{
+ RTR_e_region(r,region,len);
+}
+
+/*(defun decrypt-region (beg end key)
+ "Interactivly decrypt the region"
+ (interactive "r\nsKey:")
+ (RTR-d-region beg end (RTR-key-string-to-ints key)))*/
+static void decrypt_region(r, region, len)
+ rotorobject *r;
+ unsigned char *region;
+ int len;
+{
+ RTR_d_region(r,region,len);
+}
+
+/* Rotor methods */
+
+static void
+rotor_dealloc(xp)
+ rotorobject *xp;
+{
+ free(xp->e_rotor);
+ free(xp->d_rotor);
+ free(xp->positions);
+ free(xp->advances);
+ DEL(xp);
+}
+
+static object *
+rotor_encrypt(self, args)
+ rotorobject *self;
+ object *args;
+{
+ char *string = (char *)NULL;
+ int len = 0;
+ object *rtn = (object *)NULL;
+ char *tmp;
+
+ if (!getargs(args,"s#",&string, &len))
+ return NULL;
+ if (!(tmp = (char *)malloc(len+5))) {
+ err_nomem();
+ return NULL;
+ }
+ memset(tmp,'\0',len+1);
+ memcpy(tmp,string,len);
+ RTR_e_region(self,tmp,len);
+ rtn = newsizedstringobject(tmp,len);
+ free(tmp);
+ return(rtn);
+}
+
+static object *
+rotor_decrypt(self, args)
+ rotorobject *self;
+ object *args;
+{
+ char *string = (char *)NULL;
+ int len = 0;
+ object *rtn = (object *)NULL;
+ char *tmp;
+
+ if (!getargs(args,"s#",&string, &len))
+ return NULL;
+ if (!(tmp = (char *)malloc(len+5))) {
+ err_nomem();
+ return NULL;
+ }
+ memset(tmp,'\0',len+1);
+ memcpy(tmp,string,len);
+ RTR_d_region(self,tmp,len);
+ rtn = newsizedstringobject(tmp,len);
+ free(tmp);
+ return(rtn);
+}
+
+static object *
+rotor_setkey(self, args)
+ rotorobject *self;
+ object *args;
+{
+ char *key;
+ char *string;
+
+ if (getargs(args,"s",&string))
+ set_key(self,string);
+ INCREF(None);
+ return None;
+}
+
+static struct methodlist rotor_methods[] = {
+ {"encrypt", rotor_encrypt},
+ {"decrypt", rotor_decrypt},
+ {"setkey", rotor_setkey},
+ {NULL, NULL} /* sentinel */
+};
+
+
+/* Return a rotor object's named attribute. */
+static object *
+rotor_getattr(s, name)
+ rotorobject *s;
+ char *name;
+{
+ return findmethod(rotor_methods, (object *) s, name);
+}
+
+static typeobject Rotortype = {
+ OB_HEAD_INIT(&Typetype)
+ 0, /*ob_size*/
+ "rotor", /*tp_name*/
+ sizeof(rotorobject), /*tp_size*/
+ 0, /*tp_itemsize*/
+ /* methods */
+ rotor_dealloc, /*tp_dealloc*/
+ 0, /*tp_print*/
+ rotor_getattr, /*tp_getattr*/
+ 0, /*tp_setattr*/
+ 0, /*tp_compare*/
+ 0, /*tp_repr*/
+};
+
+
+object *rotor_rotor(self, args)
+object *args;
+{
+ char *string;
+ rotorobject *r;
+ int len;
+ int num_rotors;
+
+ if (getargs(args,"s#", &string, &len)) {
+ num_rotors = 6;
+ } else {
+ err_clear();
+ if (!getargs(args,"(s#i)", &string, &len, &num_rotors))
+ return NULL;
+ }
+ r = newrotorobject(num_rotors, string);
+ return (object *)r;
+}
+
+static struct methodlist rotor_rotor_methods[] = {
+ {"newrotor", rotor_rotor},
+ {NULL, NULL} /* Sentinel */
+};
+
+
+/* Initialize this module.
+ This is called when the first 'import rotor' is done,
+ via a table in config.c, if config.c is compiled with USE_ROTOR
+ defined. */
+
+void
+initrotor()
+{
+ object *m;
+
+ m = initmodule("rotor", rotor_rotor_methods);
+}