--- /dev/null
+/*
+ * lib/crypto/des/string2key.c
+ *
+ * based on lib/crypto/des/string2key.c from MIT V5
+ * and on lib/des/afs_string_to_key.c from UMD.
+ * constructed by Mark Eichin, Cygnus Support, 1995.
+ */
+
+#include "k5-int.h"
+#include "des_int.h"
+#include <ctype.h>
+
+static char *afs_crypt PROTOTYPE((char*,char*));
+
+krb5_error_code
+mit_afs_string_to_key (eblock, keyblock, data, salt)
+ const krb5_encrypt_block FAR * eblock;
+ krb5_keyblock FAR * keyblock;
+ const krb5_data FAR * data;
+ const krb5_data FAR * salt;
+{
+ /* totally different approach from MIT string2key. */
+ /* much of the work has already been done by the only caller
+ which is mit_des_string_to_key; in particular, *keyblock is already
+ set up. */
+
+ char *realm = salt->data;
+ register int i;
+ register krb5_octet *key = keyblock->contents;
+
+ if (data->length <= 8) {
+ char password[9]; /* trailing null for crypt() */
+ strncpy(password, realm, 8);
+ for (i=0; i<8; i++)
+ if (isupper(password[i]))
+ password[i] = tolower(password[i]);
+ for (i=0; i<data->length; i++)
+ password[i] ^= data->data[i];
+ for (i=0; i<8; i++)
+ if (password[i] == '\0')
+ password[i] = 'X';
+ strncpy(key, (char *) afs_crypt(password, "#~") + 2, 8);
+ for (i=0; i<8; i++)
+ key[i] <<= 1;
+ /* now fix up key parity again */
+ mit_des_fixup_key_parity(key);
+ /* clean & free the input string */
+ memset(password, 0, (size_t) sizeof(password));
+ } else {
+ mit_des_cblock ikey, tkey;
+
+ static mit_des_key_schedule key_sked;
+ int pw_len = strlen(realm)+data->length;
+ char *password = malloc(pw_len+1);
+ if (!password) return ENOMEM;
+
+ /* some bound checks from the original code are elided here as
+ the malloc above makes sure we have enough storage. */
+ strcpy (password, data->data);
+ for (i=data->length; *realm; i++) {
+ password[i] = *realm++;
+ if (isupper(password[i]))
+ password[i] = tolower(password[i]);
+ }
+
+ memcpy (ikey, "kerberos", sizeof(ikey));
+ memcpy (tkey, ikey, sizeof(tkey));
+ mit_des_fixup_key_parity (tkey);
+ (void) mit_des_key_sched (tkey, key_sked);
+ (void) mit_des_cbc_cksum (password, tkey, i, key_sked, ikey);
+
+ memcpy (ikey, tkey, sizeof(ikey));
+ mit_des_fixup_key_parity (tkey);
+ (void) mit_des_key_sched (tkey, key_sked);
+ (void) mit_des_cbc_cksum (password, key, i, key_sked, ikey);
+
+ /* erase key_sked */
+ memset((char *)key_sked, 0,sizeof(key_sked));
+
+ /* now fix up key parity again */
+ mit_des_fixup_key_parity(key);
+
+ /* clean & free the input string */
+ memset(password, 0, (size_t) pw_len);
+ krb5_xfree(password);
+ }
+#if 0
+ /* must free here because it was copied for this special case */
+ krb5_xfree(salt->data);
+#endif
+ return 0;
+}
+
+
+/* Portions of this code:
+ Copyright 1989 by the Massachusetts Institute of Technology
+ */
+
+/*
+ * Copyright (c) 1990 Regents of The University of Michigan.
+ * 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 appears in all
+ * copies and that both that copyright notice and this permission
+ * notice appear in supporting documentation, and that the name of
+ * The University of Michigan not be used in advertising or
+ * publicity pertaining to distribution of the software without
+ * specific, written prior permission. This software is supplied as
+ * is without expressed or implied warranties of any kind.
+ *
+ * ITD Research Systems
+ * University of Michigan
+ * 535 W. William Street
+ * Ann Arbor, Michigan
+ * +1-313-936-2652
+ * netatalk@terminator.cc.umich.edu
+ */
+
+static void krb5_afs_crypt_setkey PROTOTYPE((char*));
+static void krb5_afs_encrypt PROTOTYPE((char*,long));
+
+/*
+ * Initial permutation,
+ */
+static char IP[] = {
+ 58,50,42,34,26,18,10, 2,
+ 60,52,44,36,28,20,12, 4,
+ 62,54,46,38,30,22,14, 6,
+ 64,56,48,40,32,24,16, 8,
+ 57,49,41,33,25,17, 9, 1,
+ 59,51,43,35,27,19,11, 3,
+ 61,53,45,37,29,21,13, 5,
+ 63,55,47,39,31,23,15, 7,
+};
+
+/*
+ * Final permutation, FP = IP^(-1)
+ */
+static char FP[] = {
+ 40, 8,48,16,56,24,64,32,
+ 39, 7,47,15,55,23,63,31,
+ 38, 6,46,14,54,22,62,30,
+ 37, 5,45,13,53,21,61,29,
+ 36, 4,44,12,52,20,60,28,
+ 35, 3,43,11,51,19,59,27,
+ 34, 2,42,10,50,18,58,26,
+ 33, 1,41, 9,49,17,57,25,
+};
+
+/*
+ * Permuted-choice 1 from the key bits to yield C and D.
+ * Note that bits 8,16... are left out: They are intended for a parity check.
+ */
+static char PC1_C[] = {
+ 57,49,41,33,25,17, 9,
+ 1,58,50,42,34,26,18,
+ 10, 2,59,51,43,35,27,
+ 19,11, 3,60,52,44,36,
+};
+
+static char PC1_D[] = {
+ 63,55,47,39,31,23,15,
+ 7,62,54,46,38,30,22,
+ 14, 6,61,53,45,37,29,
+ 21,13, 5,28,20,12, 4,
+};
+
+/*
+ * Sequence of shifts used for the key schedule.
+ */
+static char shifts[] = {
+ 1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1,
+};
+
+/*
+ * Permuted-choice 2, to pick out the bits from
+ * the CD array that generate the key schedule.
+ */
+static char PC2_C[] = {
+ 14,17,11,24, 1, 5,
+ 3,28,15, 6,21,10,
+ 23,19,12, 4,26, 8,
+ 16, 7,27,20,13, 2,
+};
+
+static char PC2_D[] = {
+ 41,52,31,37,47,55,
+ 30,40,51,45,33,48,
+ 44,49,39,56,34,53,
+ 46,42,50,36,29,32,
+};
+
+/*
+ * The E bit-selection table.
+ */
+static char E[48];
+static char e[] = {
+ 32, 1, 2, 3, 4, 5,
+ 4, 5, 6, 7, 8, 9,
+ 8, 9,10,11,12,13,
+ 12,13,14,15,16,17,
+ 16,17,18,19,20,21,
+ 20,21,22,23,24,25,
+ 24,25,26,27,28,29,
+ 28,29,30,31,32, 1,
+};
+
+/*
+ * P is a permutation on the selected combination
+ * of the current L and key.
+ */
+static char P[] = {
+ 16, 7,20,21,
+ 29,12,28,17,
+ 1,15,23,26,
+ 5,18,31,10,
+ 2, 8,24,14,
+ 32,27, 3, 9,
+ 19,13,30, 6,
+ 22,11, 4,25,
+};
+
+/*
+ * The 8 selection functions.
+ * For some reason, they give a 0-origin
+ * index, unlike everything else.
+ */
+static char S[8][64] = {
+ 14, 4,13, 1, 2,15,11, 8, 3,10, 6,12, 5, 9, 0, 7,
+ 0,15, 7, 4,14, 2,13, 1,10, 6,12,11, 9, 5, 3, 8,
+ 4, 1,14, 8,13, 6, 2,11,15,12, 9, 7, 3,10, 5, 0,
+ 15,12, 8, 2, 4, 9, 1, 7, 5,11, 3,14,10, 0, 6,13,
+
+ 15, 1, 8,14, 6,11, 3, 4, 9, 7, 2,13,12, 0, 5,10,
+ 3,13, 4, 7,15, 2, 8,14,12, 0, 1,10, 6, 9,11, 5,
+ 0,14, 7,11,10, 4,13, 1, 5, 8,12, 6, 9, 3, 2,15,
+ 13, 8,10, 1, 3,15, 4, 2,11, 6, 7,12, 0, 5,14, 9,
+
+ 10, 0, 9,14, 6, 3,15, 5, 1,13,12, 7,11, 4, 2, 8,
+ 13, 7, 0, 9, 3, 4, 6,10, 2, 8, 5,14,12,11,15, 1,
+ 13, 6, 4, 9, 8,15, 3, 0,11, 1, 2,12, 5,10,14, 7,
+ 1,10,13, 0, 6, 9, 8, 7, 4,15,14, 3,11, 5, 2,12,
+
+ 7,13,14, 3, 0, 6, 9,10, 1, 2, 8, 5,11,12, 4,15,
+ 13, 8,11, 5, 6,15, 0, 3, 4, 7, 2,12, 1,10,14, 9,
+ 10, 6, 9, 0,12,11, 7,13,15, 1, 3,14, 5, 2, 8, 4,
+ 3,15, 0, 6,10, 1,13, 8, 9, 4, 5,11,12, 7, 2,14,
+
+ 2,12, 4, 1, 7,10,11, 6, 8, 5, 3,15,13, 0,14, 9,
+ 14,11, 2,12, 4, 7,13, 1, 5, 0,15,10, 3, 9, 8, 6,
+ 4, 2, 1,11,10,13, 7, 8,15, 9,12, 5, 6, 3, 0,14,
+ 11, 8,12, 7, 1,14, 2,13, 6,15, 0, 9,10, 4, 5, 3,
+
+ 12, 1,10,15, 9, 2, 6, 8, 0,13, 3, 4,14, 7, 5,11,
+ 10,15, 4, 2, 7,12, 9, 5, 6, 1,13,14, 0,11, 3, 8,
+ 9,14,15, 5, 2, 8,12, 3, 7, 0, 4,10, 1,13,11, 6,
+ 4, 3, 2,12, 9, 5,15,10,11,14, 1, 7, 6, 0, 8,13,
+
+ 4,11, 2,14,15, 0, 8,13, 3,12, 9, 7, 5,10, 6, 1,
+ 13, 0,11, 7, 4, 9, 1,10,14, 3, 5,12, 2,15, 8, 6,
+ 1, 4,11,13,12, 3, 7,14,10,15, 6, 8, 0, 5, 9, 2,
+ 6,11,13, 8, 1, 4,10, 7, 9, 5, 0,15,14, 2, 3,12,
+
+ 13, 2, 8, 4, 6,15,11, 1,10, 9, 3,14, 5, 0,12, 7,
+ 1,15,13, 8,10, 3, 7, 4,12, 5, 6,11, 0,14, 9, 2,
+ 7,11, 4, 1, 9,12,14, 2, 0, 6,10,13,15, 3, 5, 8,
+ 2, 1,14, 7, 4,10, 8,13,15,12, 9, 0, 3, 5, 6,11,
+};
+
+/*
+ * The C and D arrays used to calculate the key schedule.
+ */
+
+static char C[28];
+static char D[28];
+/*
+ * The key schedule.
+ * Generated from the key.
+ */
+static char KS[16][48];
+
+/*
+ * The current block, divided into 2 halves.
+ */
+static char L[64];
+static char *R=&L[32];
+
+static char tempL[32];
+static char f[32];
+
+/*
+ * The combination of the key and the input, before selection.
+ */
+static char preS[48];
+
+static char *afs_crypt(pw, salt)
+ char *pw;
+ char *salt;
+{
+ register i, j, c;
+ int temp;
+ static char block[66], iobuf[16];
+
+ for(i=0; i<66; i++)
+ block[i] = 0;
+ for(i=0; (c= *pw) && i<64; pw++){
+ for(j=0; j<7; j++, i++)
+ block[i] = (c>>(6-j)) & 01;
+ i++;
+ }
+
+ krb5_afs_crypt_setkey(block);
+
+ for(i=0; i<66; i++)
+ block[i] = 0;
+
+ for(i=0;i<2;i++){
+ c = *salt++;
+ iobuf[i] = c;
+ if(c>'Z') c -= 6;
+ if(c>'9') c -= 7;
+ c -= '.';
+ for(j=0;j<6;j++){
+ if((c>>j) & 01){
+ temp = E[6*i+j];
+ E[6*i+j] = E[6*i+j+24];
+ E[6*i+j+24] = temp;
+ }
+ }
+ }
+
+ for(i=0; i<25; i++)
+ krb5_afs_encrypt(block,0);
+
+ for(i=0; i<11; i++){
+ c = 0;
+ for(j=0; j<6; j++){
+ c <<= 1;
+ c |= block[6*i+j];
+ }
+ c += '.';
+ if(c>'9') c += 7;
+ if(c>'Z') c += 6;
+ iobuf[i+2] = c;
+ }
+ iobuf[i+2] = 0;
+ if(iobuf[1]==0)
+ iobuf[1] = iobuf[0];
+ return(iobuf);
+}
+
+/*
+ * Set up the key schedule from the key.
+ */
+
+static void krb5_afs_crypt_setkey(key)
+ char *key;
+{
+ register i, j, k;
+ int t;
+
+ /*
+ * First, generate C and D by permuting
+ * the key. The low order bit of each
+ * 8-bit char is not used, so C and D are only 28
+ * bits apiece.
+ */
+ for (i=0; i<28; i++) {
+ C[i] = key[PC1_C[i]-1];
+ D[i] = key[PC1_D[i]-1];
+ }
+ /*
+ * To generate Ki, rotate C and D according
+ * to schedule and pick up a permutation
+ * using PC2.
+ */
+ for (i=0; i<16; i++) {
+ /*
+ * rotate.
+ */
+ for (k=0; k<shifts[i]; k++) {
+ t = C[0];
+ for (j=0; j<28-1; j++)
+ C[j] = C[j+1];
+ C[27] = t;
+ t = D[0];
+ for (j=0; j<28-1; j++)
+ D[j] = D[j+1];
+ D[27] = t;
+ }
+ /*
+ * get Ki. Note C and D are concatenated.
+ */
+ for (j=0; j<24; j++) {
+ KS[i][j] = C[PC2_C[j]-1];
+ KS[i][j+24] = D[PC2_D[j]-28-1];
+ }
+ }
+
+ for(i=0;i<48;i++) {
+ E[i] = e[i];
+ }
+}
+
+/*
+ * The payoff: encrypt a block.
+ */
+
+static void krb5_afs_encrypt(block, edflag)
+ char *block;
+ long edflag;
+{
+ int i, ii;
+ register t, j, k;
+
+ /*
+ * First, permute the bits in the input
+ */
+ for (j=0; j<64; j++)
+ L[j] = block[IP[j]-1];
+ /*
+ * Perform an encryption operation 16 times.
+ */
+ for (ii=0; ii<16; ii++) {
+ /*
+ * Set direction
+ */
+ if (edflag)
+ i = 15-ii;
+ else
+ i = ii;
+ /*
+ * Save the R array,
+ * which will be the new L.
+ */
+ for (j=0; j<32; j++)
+ tempL[j] = R[j];
+ /*
+ * Expand R to 48 bits using the E selector;
+ * exclusive-or with the current key bits.
+ */
+ for (j=0; j<48; j++)
+ preS[j] = R[E[j]-1] ^ KS[i][j];
+ /*
+ * The pre-select bits are now considered
+ * in 8 groups of 6 bits each.
+ * The 8 selection functions map these
+ * 6-bit quantities into 4-bit quantities
+ * and the results permuted
+ * to make an f(R, K).
+ * The indexing into the selection functions
+ * is peculiar; it could be simplified by
+ * rewriting the tables.
+ */
+ for (j=0; j<8; j++) {
+ t = 6*j;
+ k = S[j][(preS[t+0]<<5)+
+ (preS[t+1]<<3)+
+ (preS[t+2]<<2)+
+ (preS[t+3]<<1)+
+ (preS[t+4]<<0)+
+ (preS[t+5]<<4)];
+ t = 4*j;
+ f[t+0] = (k>>3)&01;
+ f[t+1] = (k>>2)&01;
+ f[t+2] = (k>>1)&01;
+ f[t+3] = (k>>0)&01;
+ }
+ /*
+ * The new R is L ^ f(R, K).
+ * The f here has to be permuted first, though.
+ */
+ for (j=0; j<32; j++)
+ R[j] = L[j] ^ f[P[j]-1];
+ /*
+ * Finally, the new L (the original R)
+ * is copied back.
+ */
+ for (j=0; j<32; j++)
+ L[j] = tempL[j];
+ }
+ /*
+ * The output L and R are reversed.
+ */
+ for (j=0; j<32; j++) {
+ t = L[j];
+ L[j] = R[j];
+ R[j] = t;
+ }
+ /*
+ * The final output
+ * gets the inverse permutation of the very original.
+ */
+ for (j=0; j<64; j++)
+ block[j] = L[FP[j]-1];
+}
projects / krb5.git / commitdiff