From 21073bff847fbc41d3dab0a649fa400d8188fa16 Mon Sep 17 00:00:00 2001
From: Isaac Boukris <iboukris@gmail.com>
Date: Sat, 19 Oct 2019 23:48:19 +0300
Subject: [PATCH 1/2] smbdes: add des_crypt56_gnutls() using use DES-CBC with
 zeroed IV

Signed-off-by: Isaac Boukris <iboukris@gmail.com>
---
 libcli/auth/smbdes.c | 47 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/libcli/auth/smbdes.c b/libcli/auth/smbdes.c
index 6d9a6dc2ce8..37ede91ad22 100644
--- a/libcli/auth/smbdes.c
+++ b/libcli/auth/smbdes.c
@@ -23,6 +23,9 @@
 #include "includes.h"
 #include "libcli/auth/libcli_auth.h"
 
+#include <gnutls/gnutls.h>
+#include <gnutls/crypto.h>
+
 /* NOTES: 
 
    This code makes no attempt to be fast! In fact, it is a very
@@ -273,6 +276,50 @@ static void str_to_key(const uint8_t *str,uint8_t *key)
 	}
 }
 
+static int des_crypt56_gnutls(uint8_t out[8], const uint8_t in[8],
+			      const uint8_t key_in[7], bool enc)
+{
+	static uint8_t iv8[8];
+	gnutls_datum_t iv = { iv8, 8 };
+	gnutls_datum_t key;
+	gnutls_cipher_hd_t ctx;
+	uint8_t key2[8];
+	uint8_t outb[8];
+	int ret;
+
+	memset(out, 0, 8);
+
+	str_to_key(key_in, key2);
+
+	key.data = key2;
+	key.size = 8;
+
+	ret = gnutls_global_init();
+	if (ret != 0) {
+		return ret;
+	}
+
+	ret = gnutls_cipher_init(&ctx, GNUTLS_CIPHER_DES_CBC, &key, &iv);
+	if (ret != 0) {
+		return ret;
+	}
+
+	memcpy(outb, in, 8);
+	if (enc) {
+		ret = gnutls_cipher_encrypt(ctx, outb, 8);
+	} else {
+		ret = gnutls_cipher_decrypt(ctx, outb, 8);
+	}
+
+	if (ret == 0) {
+		memcpy(out, outb, 8);
+	}
+
+	gnutls_cipher_deinit(ctx);
+
+	return ret;
+}
+
 /*
   basic des crypt using a 56 bit (7 byte) key
 */
-- 
2.22.0


From 6d6651213f391840e3004ec3b055f8f25be9b360 Mon Sep 17 00:00:00 2001
From: Isaac Boukris <iboukris@gmail.com>
Date: Mon, 21 Oct 2019 20:03:04 +0300
Subject: [PATCH 2/2] smbdes: use the new des_crypt56_gnutls()

and remove builtin DES crypto.

Signed-off-by: Isaac Boukris <iboukris@gmail.com>
---
 libcli/auth/smbdes.c | 258 +------------------------------------------
 1 file changed, 1 insertion(+), 257 deletions(-)

diff --git a/libcli/auth/smbdes.c b/libcli/auth/smbdes.c
index 37ede91ad22..7de05b75303 100644
--- a/libcli/auth/smbdes.c
+++ b/libcli/auth/smbdes.c
@@ -26,239 +26,6 @@
 #include <gnutls/gnutls.h>
 #include <gnutls/crypto.h>
 
-/* NOTES: 
-
-   This code makes no attempt to be fast! In fact, it is a very
-   slow implementation 
-
-   This code is NOT a complete DES implementation. It implements only
-   the minimum necessary for SMB authentication, as used by all SMB
-   products (including every copy of Microsoft Windows95 ever sold)
-
-   In particular, it can only do a unchained forward DES pass. This
-   means it is not possible to use this code for encryption/decryption
-   of data, instead it is only useful as a "hash" algorithm.
-
-   There is no entry point into this code that allows normal DES operation.
-
-   I believe this means that this code does not come under ITAR
-   regulations but this is NOT a legal opinion. If you are concerned
-   about the applicability of ITAR regulations to this code then you
-   should confirm it for yourself (and maybe let me know if you come
-   up with a different answer to the one above)
-*/
-
-
-static const uint8_t perm1[56] = {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,
-			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};
-
-static const uint8_t perm2[48] = {14, 17, 11, 24,  1,  5,
-                         3, 28, 15,  6, 21, 10,
-                        23, 19, 12,  4, 26,  8,
-                        16,  7, 27, 20, 13,  2,
-                        41, 52, 31, 37, 47, 55,
-                        30, 40, 51, 45, 33, 48,
-                        44, 49, 39, 56, 34, 53,
-                        46, 42, 50, 36, 29, 32};
-
-static const uint8_t perm3[64] = {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};
-
-static const uint8_t perm4[48] = {   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};
-
-static const uint8_t perm5[32] = {      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};
-
-
-static const uint8_t perm6[64] ={ 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};
-
-
-static const uint8_t sc[16] = {1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1};
-
-static const uint8_t sbox[8][4][16] = {
-	{{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}}};
-
-static void permute(char *out, const char *in, const uint8_t *p, int n)
-{
-	int i;
-	for (i=0;i<n;i++)
-		out[i] = in[p[i]-1];
-}
-
-static void lshift(char *d, int count, int n)
-{
-	char out[64];
-	int i;
-	for (i=0;i<n;i++)
-		out[i] = d[(i+count)%n];
-	for (i=0;i<n;i++)
-		d[i] = out[i];
-}
-
-static void concat(char *out, char *in1, char *in2, int l1, int l2)
-{
-	while (l1--)
-		*out++ = *in1++;
-	while (l2--)
-		*out++ = *in2++;
-}
-
-static void xor(char *out, char *in1, char *in2, int n)
-{
-	int i;
-	for (i=0;i<n;i++)
-		out[i] = in1[i] ^ in2[i];
-}
-
-static void dohash(char *out, char *in, char *key, int forw)
-{
-	int i, j, k;
-	char pk1[56];
-	char c[28];
-	char d[28];
-	char cd[56];
-	char ki[16][48];
-	char pd1[64];
-	char l[32], r[32];
-	char rl[64];
-
-	permute(pk1, key, perm1, 56);
-
-	for (i=0;i<28;i++)
-		c[i] = pk1[i];
-	for (i=0;i<28;i++)
-		d[i] = pk1[i+28];
-
-	for (i=0;i<16;i++) {
-		lshift(c, sc[i], 28);
-		lshift(d, sc[i], 28);
-
-		concat(cd, c, d, 28, 28); 
-		permute(ki[i], cd, perm2, 48); 
-	}
-
-	permute(pd1, in, perm3, 64);
-
-	for (j=0;j<32;j++) {
-		l[j] = pd1[j];
-		r[j] = pd1[j+32];
-	}
-
-	for (i=0;i<16;i++) {
-		char er[48];
-		char erk[48];
-		char b[8][6];
-		char cb[32];
-		char pcb[32];
-		char r2[32];
-
-		permute(er, r, perm4, 48);
-
-		xor(erk, er, ki[forw ? i : 15 - i], 48);
-
-		for (j=0;j<8;j++)
-			for (k=0;k<6;k++)
-				b[j][k] = erk[j*6 + k];
-
-		for (j=0;j<8;j++) {
-			int m, n;
-			m = (b[j][0]<<1) | b[j][5];
-
-			n = (b[j][1]<<3) | (b[j][2]<<2) | (b[j][3]<<1) | b[j][4]; 
-
-			for (k=0;k<4;k++) 
-				b[j][k] = (sbox[j][m][n] & (1<<(3-k)))?1:0; 
-		}
-
-		for (j=0;j<8;j++)
-			for (k=0;k<4;k++)
-				cb[j*4+k] = b[j][k];
-		permute(pcb, cb, perm5, 32);
-
-		xor(r2, l, pcb, 32);
-
-		for (j=0;j<32;j++)
-			l[j] = r[j];
-
-		for (j=0;j<32;j++)
-			r[j] = r2[j];
-	}
-
-	concat(rl, r, l, 32, 32);
-
-	permute(out, rl, perm6, 64);
-}
-
 static void str_to_key(const uint8_t *str,uint8_t *key)
 {
 	int i;
@@ -325,30 +92,7 @@ static int des_crypt56_gnutls(uint8_t out[8], const uint8_t in[8],
 */
 void des_crypt56(uint8_t out[8], const uint8_t in[8], const uint8_t key[7], int forw)
 {
-	int i;
-	char outb[64];
-	char inb[64];
-	char keyb[64];
-	uint8_t key2[8];
-
-	str_to_key(key, key2);
-
-	for (i=0;i<64;i++) {
-		inb[i] = (in[i/8] & (1<<(7-(i%8)))) ? 1 : 0;
-		keyb[i] = (key2[i/8] & (1<<(7-(i%8)))) ? 1 : 0;
-		outb[i] = 0;
-	}
-
-	dohash(outb, inb, keyb, forw);
-
-	for (i=0;i<8;i++) {
-		out[i] = 0;
-	}
-
-	for (i=0;i<64;i++) {
-		if (outb[i])
-			out[i/8] |= (1<<(7-(i%8)));
-	}
+	(void)des_crypt56_gnutls(out, in, key, forw);
 }
 
 void E_P16(const uint8_t *p14,uint8_t *p16)
-- 
2.22.0