- (djm) Big OpenBSD sync:

   - markus@cvs.openbsd.org  2000/09/30 10:27:44
     [log.c]
     allow loglevel debug
   - markus@cvs.openbsd.org  2000/10/03 11:59:57
     [packet.c]
     hmac->mac
   - markus@cvs.openbsd.org  2000/10/03 12:03:03
     [auth-krb4.c auth-passwd.c auth-rh-rsa.c auth-rhosts.c auth-rsa.c auth1.c]
     move fake-auth from auth1.c to individual auth methods, disables s/key in
     debug-msg
   - markus@cvs.openbsd.org  2000/10/03 12:16:48
     ssh.c
     do not resolve canonname, i have no idea why this was added oin ossh
   - markus@cvs.openbsd.org  2000/10/09 15:30:44
     ssh-keygen.1 ssh-keygen.c
     -X now reads private ssh.com DSA keys, too.
   - markus@cvs.openbsd.org  2000/10/09 15:32:34
     auth-options.c
     clear options on every call.
   - markus@cvs.openbsd.org  2000/10/09 15:51:00
     authfd.c authfd.h
     interop with ssh-agent2, from <res@shore.net>
   - markus@cvs.openbsd.org  2000/10/10 14:20:45
     compat.c
     use rexexp for version string matching
   - provos@cvs.openbsd.org  2000/10/10 22:02:18
     [kex.c kex.h myproposal.h ssh.h ssh2.h sshconnect2.c sshd.c dh.c dh.h]
     First rough implementation of the diffie-hellman group exchange.  The
     client can ask the server for bigger groups to perform the diffie-hellman
     in, thus increasing the attack complexity when using ciphers with longer
     keys.  University of Windsor provided network, T the company.
   - markus@cvs.openbsd.org  2000/10/11 13:59:52
     [auth-rsa.c auth2.c]
     clear auth options unless auth sucessfull
   - markus@cvs.openbsd.org  2000/10/11 14:00:27
     [auth-options.h]
     clear auth options unless auth sucessfull
   - markus@cvs.openbsd.org  2000/10/11 14:03:27
     [scp.1 scp.c]
     support 'scp -o' with help from mouring@pconline.com
   - markus@cvs.openbsd.org  2000/10/11 14:11:35
     [dh.c]
     Wall
   - markus@cvs.openbsd.org  2000/10/11 14:14:40
     [auth.h auth2.c readconf.c readconf.h readpass.c servconf.c servconf.h]
     [ssh.h sshconnect2.c sshd_config auth2-skey.c cli.c cli.h]
     add support for s/key (kbd-interactive) to ssh2, based on work by
     mkiernan@avantgo.com and me
   - markus@cvs.openbsd.org  2000/10/11 14:27:24
     [auth.c auth1.c auth2.c authfile.c cipher.c cipher.h kex.c kex.h]
     [myproposal.h packet.c readconf.c session.c ssh.c ssh.h sshconnect1.c]
     [sshconnect2.c sshd.c]
     new cipher framework
   - markus@cvs.openbsd.org  2000/10/11 14:45:21
     [cipher.c]
     remove DES
   - markus@cvs.openbsd.org  2000/10/12 03:59:20
     [cipher.c cipher.h sshconnect1.c sshconnect2.c sshd.c]
     enable DES in SSH-1 clients only
   - markus@cvs.openbsd.org  2000/10/12 08:21:13
     [kex.h packet.c]
     remove unused
   - markus@cvs.openbsd.org  2000/10/13 12:34:46
     [sshd.c]
     Kludge for F-Secure Macintosh < 1.0.2; appro@fy.chalmers.se
   - markus@cvs.openbsd.org  2000/10/13 12:59:15
     [cipher.c cipher.h myproposal.h  rijndael.c rijndael.h]
     rijndael/aes support
   - markus@cvs.openbsd.org  2000/10/13 13:10:54
     [sshd.8]
     more info about -V
   - markus@cvs.openbsd.org  2000/10/13 13:12:02
     [myproposal.h]
     prefer no compression

1 files changed, 493 insertions, 0 deletions

diff --git a/rijndael.c b/rijndael.c
new file mode 100644
index 00000000..bb592bc2
--- /dev/null
+++ b/rijndael.c
@@ -0,0 +1,493 @@
+/*	$OpenBSD: rijndael.c,v 1.1 2000/10/13 18:59:14 markus Exp $	*/
+
+/* This is an independent implementation of the encryption algorithm:   */
+/*                                                                      */
+/*         RIJNDAEL by Joan Daemen and Vincent Rijmen                   */
+/*                                                                      */
+/* which is a candidate algorithm in the Advanced Encryption Standard   */
+/* programme of the US National Institute of Standards and Technology.  */
+/*                                                                      */
+/* Copyright in this implementation is held by Dr B R Gladman but I     */
+/* hereby give permission for its free direct or derivative use subject */
+/* to acknowledgment of its origin and compliance with any conditions   */
+/* that the originators of the algorithm place on its exploitation.     */
+/*                                                                      */
+/* Dr Brian Gladman (gladman@seven77.demon.co.uk) 14th January 1999     */
+
+/* Timing data for Rijndael (rijndael.c)
+
+Algorithm: rijndael (rijndael.c)
+
+128 bit key:
+Key Setup:    305/1389 cycles (encrypt/decrypt)
+Encrypt:       374 cycles =    68.4 mbits/sec
+Decrypt:       352 cycles =    72.7 mbits/sec
+Mean:          363 cycles =    70.5 mbits/sec
+
+192 bit key:
+Key Setup:    277/1595 cycles (encrypt/decrypt)
+Encrypt:       439 cycles =    58.3 mbits/sec
+Decrypt:       425 cycles =    60.2 mbits/sec
+Mean:          432 cycles =    59.3 mbits/sec
+
+256 bit key:
+Key Setup:    374/1960 cycles (encrypt/decrypt)
+Encrypt:       502 cycles =    51.0 mbits/sec
+Decrypt:       498 cycles =    51.4 mbits/sec
+Mean:          500 cycles =    51.2 mbits/sec
+
+*/
+
+#include <sys/types.h>
+#include "rijndael.h"
+
+void gen_tabs	__P((void));
+
+/* 3. Basic macros for speeding up generic operations               */
+
+/* Circular rotate of 32 bit values                                 */
+
+#define rotr(x,n)   (((x) >> ((int)(n))) | ((x) << (32 - (int)(n))))
+#define rotl(x,n)   (((x) << ((int)(n))) | ((x) >> (32 - (int)(n))))
+
+/* Invert byte order in a 32 bit variable                           */
+
+#define bswap(x)    (rotl(x, 8) & 0x00ff00ff | rotr(x, 8) & 0xff00ff00)
+
+/* Extract byte from a 32 bit quantity (little endian notation)     */ 
+
+#define byte(x,n)   ((u1byte)((x) >> (8 * n)))
+
+#if BYTE_ORDER != LITTLE_ENDIAN
+#define BLOCK_SWAP
+#endif
+
+/* For inverting byte order in input/output 32 bit words if needed  */
+
+#ifdef  BLOCK_SWAP
+#define BYTE_SWAP
+#define WORD_SWAP
+#endif
+
+#ifdef  BYTE_SWAP
+#define io_swap(x)  bswap(x)
+#else
+#define io_swap(x)  (x)
+#endif
+
+/* For inverting the byte order of input/output blocks if needed    */
+
+#ifdef  WORD_SWAP
+
+#define get_block(x)                            \
+    ((u4byte*)(x))[0] = io_swap(in_blk[3]);     \
+    ((u4byte*)(x))[1] = io_swap(in_blk[2]);     \
+    ((u4byte*)(x))[2] = io_swap(in_blk[1]);     \
+    ((u4byte*)(x))[3] = io_swap(in_blk[0])
+
+#define put_block(x)                            \
+    out_blk[3] = io_swap(((u4byte*)(x))[0]);    \
+    out_blk[2] = io_swap(((u4byte*)(x))[1]);    \
+    out_blk[1] = io_swap(((u4byte*)(x))[2]);    \
+    out_blk[0] = io_swap(((u4byte*)(x))[3])
+
+#define get_key(x,len)                          \
+    ((u4byte*)(x))[4] = ((u4byte*)(x))[5] =     \
+    ((u4byte*)(x))[6] = ((u4byte*)(x))[7] = 0;  \
+    switch((((len) + 63) / 64)) {               \
+    case 2:                                     \
+    ((u4byte*)(x))[0] = io_swap(in_key[3]);     \
+    ((u4byte*)(x))[1] = io_swap(in_key[2]);     \
+    ((u4byte*)(x))[2] = io_swap(in_key[1]);     \
+    ((u4byte*)(x))[3] = io_swap(in_key[0]);     \
+    break;                                      \
+    case 3:                                     \
+    ((u4byte*)(x))[0] = io_swap(in_key[5]);     \
+    ((u4byte*)(x))[1] = io_swap(in_key[4]);     \
+    ((u4byte*)(x))[2] = io_swap(in_key[3]);     \
+    ((u4byte*)(x))[3] = io_swap(in_key[2]);     \
+    ((u4byte*)(x))[4] = io_swap(in_key[1]);     \
+    ((u4byte*)(x))[5] = io_swap(in_key[0]);     \
+    break;                                      \
+    case 4:                                     \
+    ((u4byte*)(x))[0] = io_swap(in_key[7]);     \
+    ((u4byte*)(x))[1] = io_swap(in_key[6]);     \
+    ((u4byte*)(x))[2] = io_swap(in_key[5]);     \
+    ((u4byte*)(x))[3] = io_swap(in_key[4]);     \
+    ((u4byte*)(x))[4] = io_swap(in_key[3]);     \
+    ((u4byte*)(x))[5] = io_swap(in_key[2]);     \
+    ((u4byte*)(x))[6] = io_swap(in_key[1]);     \
+    ((u4byte*)(x))[7] = io_swap(in_key[0]);     \
+    }
+
+#else
+
+#define get_block(x)                            \
+    ((u4byte*)(x))[0] = io_swap(in_blk[0]);     \
+    ((u4byte*)(x))[1] = io_swap(in_blk[1]);     \
+    ((u4byte*)(x))[2] = io_swap(in_blk[2]);     \
+    ((u4byte*)(x))[3] = io_swap(in_blk[3])
+
+#define put_block(x)                            \
+    out_blk[0] = io_swap(((u4byte*)(x))[0]);    \
+    out_blk[1] = io_swap(((u4byte*)(x))[1]);    \
+    out_blk[2] = io_swap(((u4byte*)(x))[2]);    \
+    out_blk[3] = io_swap(((u4byte*)(x))[3])
+
+#define get_key(x,len)                          \
+    ((u4byte*)(x))[4] = ((u4byte*)(x))[5] =     \
+    ((u4byte*)(x))[6] = ((u4byte*)(x))[7] = 0;  \
+    switch((((len) + 63) / 64)) {               \
+    case 4:                                     \
+    ((u4byte*)(x))[6] = io_swap(in_key[6]);     \
+    ((u4byte*)(x))[7] = io_swap(in_key[7]);     \
+    case 3:                                     \
+    ((u4byte*)(x))[4] = io_swap(in_key[4]);     \
+    ((u4byte*)(x))[5] = io_swap(in_key[5]);     \
+    case 2:                                     \
+    ((u4byte*)(x))[0] = io_swap(in_key[0]);     \
+    ((u4byte*)(x))[1] = io_swap(in_key[1]);     \
+    ((u4byte*)(x))[2] = io_swap(in_key[2]);     \
+    ((u4byte*)(x))[3] = io_swap(in_key[3]);     \
+    }
+
+#endif
+
+#define LARGE_TABLES
+
+u1byte  pow_tab[256];
+u1byte  log_tab[256];
+u1byte  sbx_tab[256];
+u1byte  isb_tab[256];
+u4byte  rco_tab[ 10];
+u4byte  ft_tab[4][256];
+u4byte  it_tab[4][256];
+
+#ifdef  LARGE_TABLES
+  u4byte  fl_tab[4][256];
+  u4byte  il_tab[4][256];
+#endif
+
+u4byte  tab_gen = 0;
+
+#define ff_mult(a,b)    (a && b ? pow_tab[(log_tab[a] + log_tab[b]) % 255] : 0)
+
+#define f_rn(bo, bi, n, k)                          \
+    bo[n] =  ft_tab[0][byte(bi[n],0)] ^             \
+             ft_tab[1][byte(bi[(n + 1) & 3],1)] ^   \
+             ft_tab[2][byte(bi[(n + 2) & 3],2)] ^   \
+             ft_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n)
+
+#define i_rn(bo, bi, n, k)                          \
+    bo[n] =  it_tab[0][byte(bi[n],0)] ^             \
+             it_tab[1][byte(bi[(n + 3) & 3],1)] ^   \
+             it_tab[2][byte(bi[(n + 2) & 3],2)] ^   \
+             it_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n)
+
+#ifdef LARGE_TABLES
+
+#define ls_box(x)                \
+    ( fl_tab[0][byte(x, 0)] ^    \
+      fl_tab[1][byte(x, 1)] ^    \
+      fl_tab[2][byte(x, 2)] ^    \
+      fl_tab[3][byte(x, 3)] )
+
+#define f_rl(bo, bi, n, k)                          \
+    bo[n] =  fl_tab[0][byte(bi[n],0)] ^             \
+             fl_tab[1][byte(bi[(n + 1) & 3],1)] ^   \
+             fl_tab[2][byte(bi[(n + 2) & 3],2)] ^   \
+             fl_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n)
+
+#define i_rl(bo, bi, n, k)                          \
+    bo[n] =  il_tab[0][byte(bi[n],0)] ^             \
+             il_tab[1][byte(bi[(n + 3) & 3],1)] ^   \
+             il_tab[2][byte(bi[(n + 2) & 3],2)] ^   \
+             il_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n)
+
+#else
+
+#define ls_box(x)                            \
+    ((u4byte)sbx_tab[byte(x, 0)] <<  0) ^    \
+    ((u4byte)sbx_tab[byte(x, 1)] <<  8) ^    \
+    ((u4byte)sbx_tab[byte(x, 2)] << 16) ^    \
+    ((u4byte)sbx_tab[byte(x, 3)] << 24)
+
+#define f_rl(bo, bi, n, k)                                      \
+    bo[n] = (u4byte)sbx_tab[byte(bi[n],0)] ^                    \
+        rotl(((u4byte)sbx_tab[byte(bi[(n + 1) & 3],1)]),  8) ^  \
+        rotl(((u4byte)sbx_tab[byte(bi[(n + 2) & 3],2)]), 16) ^  \
+        rotl(((u4byte)sbx_tab[byte(bi[(n + 3) & 3],3)]), 24) ^ *(k + n)
+
+#define i_rl(bo, bi, n, k)                                      \
+    bo[n] = (u4byte)isb_tab[byte(bi[n],0)] ^                    \
+        rotl(((u4byte)isb_tab[byte(bi[(n + 3) & 3],1)]),  8) ^  \
+        rotl(((u4byte)isb_tab[byte(bi[(n + 2) & 3],2)]), 16) ^  \
+        rotl(((u4byte)isb_tab[byte(bi[(n + 1) & 3],3)]), 24) ^ *(k + n)
+
+#endif
+
+void
+gen_tabs(void)
+{
+	u4byte  i, t;
+	u1byte  p, q;
+
+	/* log and power tables for GF(2**8) finite field with  */
+	/* 0x11b as modular polynomial - the simplest prmitive  */
+	/* root is 0x11, used here to generate the tables       */
+
+	for(i = 0,p = 1; i < 256; ++i) {
+		pow_tab[i] = (u1byte)p; log_tab[p] = (u1byte)i;
+
+		p = p ^ (p << 1) ^ (p & 0x80 ? 0x01b : 0);
+	}
+
+	log_tab[1] = 0; p = 1;
+
+	for(i = 0; i < 10; ++i) {
+		rco_tab[i] = p; 
+
+		p = (p << 1) ^ (p & 0x80 ? 0x1b : 0);
+	}
+
+	/* note that the affine byte transformation matrix in   */
+	/* rijndael specification is in big endian format with  */
+	/* bit 0 as the most significant bit. In the remainder  */
+	/* of the specification the bits are numbered from the  */
+	/* least significant end of a byte.                     */
+
+	for(i = 0; i < 256; ++i) {
+		p = (i ? pow_tab[255 - log_tab[i]] : 0); q = p; 
+		q = (q >> 7) | (q << 1); p ^= q; 
+		q = (q >> 7) | (q << 1); p ^= q; 
+		q = (q >> 7) | (q << 1); p ^= q; 
+		q = (q >> 7) | (q << 1); p ^= q ^ 0x63; 
+		sbx_tab[i] = (u1byte)p; isb_tab[p] = (u1byte)i;
+	}
+
+	for(i = 0; i < 256; ++i) {
+		p = sbx_tab[i]; 
+
+#ifdef  LARGE_TABLES        
+        
+		t = p; fl_tab[0][i] = t;
+		fl_tab[1][i] = rotl(t,  8);
+		fl_tab[2][i] = rotl(t, 16);
+		fl_tab[3][i] = rotl(t, 24);
+#endif
+		t = ((u4byte)ff_mult(2, p)) |
+			((u4byte)p <<  8) |
+			((u4byte)p << 16) |
+			((u4byte)ff_mult(3, p) << 24);
+        
+		ft_tab[0][i] = t;
+		ft_tab[1][i] = rotl(t,  8);
+		ft_tab[2][i] = rotl(t, 16);
+		ft_tab[3][i] = rotl(t, 24);
+
+		p = isb_tab[i]; 
+
+#ifdef  LARGE_TABLES        
+        
+		t = p; il_tab[0][i] = t; 
+		il_tab[1][i] = rotl(t,  8); 
+		il_tab[2][i] = rotl(t, 16); 
+		il_tab[3][i] = rotl(t, 24);
+#endif 
+		t = ((u4byte)ff_mult(14, p)) |
+			((u4byte)ff_mult( 9, p) <<  8) |
+			((u4byte)ff_mult(13, p) << 16) |
+			((u4byte)ff_mult(11, p) << 24);
+        
+		it_tab[0][i] = t; 
+		it_tab[1][i] = rotl(t,  8); 
+		it_tab[2][i] = rotl(t, 16); 
+		it_tab[3][i] = rotl(t, 24); 
+	}
+
+	tab_gen = 1;
+};
+
+#define star_x(x) (((x) & 0x7f7f7f7f) << 1) ^ ((((x) & 0x80808080) >> 7) * 0x1b)
+
+#define imix_col(y,x)       \
+    u   = star_x(x);        \
+    v   = star_x(u);        \
+    w   = star_x(v);        \
+    t   = w ^ (x);          \
+   (y)  = u ^ v ^ w;        \
+   (y) ^= rotr(u ^ t,  8) ^ \
+          rotr(v ^ t, 16) ^ \
+          rotr(t,24)
+
+/* initialise the key schedule from the user supplied key   */
+
+#define loop4(i)                                    \
+{   t = ls_box(rotr(t,  8)) ^ rco_tab[i];           \
+    t ^= e_key[4 * i];     e_key[4 * i + 4] = t;    \
+    t ^= e_key[4 * i + 1]; e_key[4 * i + 5] = t;    \
+    t ^= e_key[4 * i + 2]; e_key[4 * i + 6] = t;    \
+    t ^= e_key[4 * i + 3]; e_key[4 * i + 7] = t;    \
+}
+
+#define loop6(i)                                    \
+{   t = ls_box(rotr(t,  8)) ^ rco_tab[i];           \
+    t ^= e_key[6 * i];     e_key[6 * i + 6] = t;    \
+    t ^= e_key[6 * i + 1]; e_key[6 * i + 7] = t;    \
+    t ^= e_key[6 * i + 2]; e_key[6 * i + 8] = t;    \
+    t ^= e_key[6 * i + 3]; e_key[6 * i + 9] = t;    \
+    t ^= e_key[6 * i + 4]; e_key[6 * i + 10] = t;   \
+    t ^= e_key[6 * i + 5]; e_key[6 * i + 11] = t;   \
+}
+
+#define loop8(i)                                    \
+{   t = ls_box(rotr(t,  8)) ^ rco_tab[i];           \
+    t ^= e_key[8 * i];     e_key[8 * i + 8] = t;    \
+    t ^= e_key[8 * i + 1]; e_key[8 * i + 9] = t;    \
+    t ^= e_key[8 * i + 2]; e_key[8 * i + 10] = t;   \
+    t ^= e_key[8 * i + 3]; e_key[8 * i + 11] = t;   \
+    t  = e_key[8 * i + 4] ^ ls_box(t);              \
+    e_key[8 * i + 12] = t;                          \
+    t ^= e_key[8 * i + 5]; e_key[8 * i + 13] = t;   \
+    t ^= e_key[8 * i + 6]; e_key[8 * i + 14] = t;   \
+    t ^= e_key[8 * i + 7]; e_key[8 * i + 15] = t;   \
+}
+
+rijndael_ctx *
+rijndael_set_key(rijndael_ctx *ctx, const u4byte *in_key, const u4byte key_len,
+		 int encrypt)
+{  
+	u4byte  i, t, u, v, w;
+	u4byte *e_key = ctx->e_key;
+	u4byte *d_key = ctx->d_key;
+
+	ctx->decrypt = !encrypt;
+
+	if(!tab_gen)
+		gen_tabs();
+
+	ctx->k_len = (key_len + 31) / 32;
+
+	e_key[0] = in_key[0]; e_key[1] = in_key[1];
+	e_key[2] = in_key[2]; e_key[3] = in_key[3];
+	
+	switch(ctx->k_len) {
+        case 4: t = e_key[3];
+                for(i = 0; i < 10; ++i) 
+			loop4(i);
+                break;
+
+        case 6: e_key[4] = in_key[4]; t = e_key[5] = in_key[5];
+                for(i = 0; i < 8; ++i) 
+			loop6(i);
+                break;
+
+        case 8: e_key[4] = in_key[4]; e_key[5] = in_key[5];
+                e_key[6] = in_key[6]; t = e_key[7] = in_key[7];
+                for(i = 0; i < 7; ++i) 
+			loop8(i);
+                break;
+	}
+
+	if (!encrypt) {
+		d_key[0] = e_key[0]; d_key[1] = e_key[1];
+		d_key[2] = e_key[2]; d_key[3] = e_key[3];
+
+		for(i = 4; i < 4 * ctx->k_len + 24; ++i) {
+			imix_col(d_key[i], e_key[i]);
+		}
+	}
+
+	return ctx;
+};
+
+/* encrypt a block of text  */
+
+#define f_nround(bo, bi, k) \
+    f_rn(bo, bi, 0, k);     \
+    f_rn(bo, bi, 1, k);     \
+    f_rn(bo, bi, 2, k);     \
+    f_rn(bo, bi, 3, k);     \
+    k += 4
+
+#define f_lround(bo, bi, k) \
+    f_rl(bo, bi, 0, k);     \
+    f_rl(bo, bi, 1, k);     \
+    f_rl(bo, bi, 2, k);     \
+    f_rl(bo, bi, 3, k)
+
+void
+rijndael_encrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk)
+{   
+	u4byte k_len = ctx->k_len;
+	u4byte *e_key = ctx->e_key;
+	u4byte  b0[4], b1[4], *kp;
+
+	b0[0] = in_blk[0] ^ e_key[0]; b0[1] = in_blk[1] ^ e_key[1];
+	b0[2] = in_blk[2] ^ e_key[2]; b0[3] = in_blk[3] ^ e_key[3];
+
+	kp = e_key + 4;
+
+	if(k_len > 6) {
+		f_nround(b1, b0, kp); f_nround(b0, b1, kp);
+	}
+
+	if(k_len > 4) {
+		f_nround(b1, b0, kp); f_nround(b0, b1, kp);
+	}
+
+	f_nround(b1, b0, kp); f_nround(b0, b1, kp);
+	f_nround(b1, b0, kp); f_nround(b0, b1, kp);
+	f_nround(b1, b0, kp); f_nround(b0, b1, kp);
+	f_nround(b1, b0, kp); f_nround(b0, b1, kp);
+	f_nround(b1, b0, kp); f_lround(b0, b1, kp);
+
+	out_blk[0] = b0[0]; out_blk[1] = b0[1];
+	out_blk[2] = b0[2]; out_blk[3] = b0[3];
+};
+
+/* decrypt a block of text  */
+
+#define i_nround(bo, bi, k) \
+    i_rn(bo, bi, 0, k);     \
+    i_rn(bo, bi, 1, k);     \
+    i_rn(bo, bi, 2, k);     \
+    i_rn(bo, bi, 3, k);     \
+    k -= 4
+
+#define i_lround(bo, bi, k) \
+    i_rl(bo, bi, 0, k);     \
+    i_rl(bo, bi, 1, k);     \
+    i_rl(bo, bi, 2, k);     \
+    i_rl(bo, bi, 3, k)
+
+void
+rijndael_decrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk)
+{  
+	u4byte  b0[4], b1[4], *kp;
+	u4byte k_len = ctx->k_len;
+	u4byte *e_key = ctx->e_key;
+	u4byte *d_key = ctx->d_key;
+
+	b0[0] = in_blk[0] ^ e_key[4 * k_len + 24]; b0[1] = in_blk[1] ^ e_key[4 * k_len + 25];
+	b0[2] = in_blk[2] ^ e_key[4 * k_len + 26]; b0[3] = in_blk[3] ^ e_key[4 * k_len + 27];
+
+	kp = d_key + 4 * (k_len + 5);
+
+	if(k_len > 6) {
+		i_nround(b1, b0, kp); i_nround(b0, b1, kp);
+	}
+
+	if(k_len > 4) {
+		i_nround(b1, b0, kp); i_nround(b0, b1, kp);
+	}
+
+	i_nround(b1, b0, kp); i_nround(b0, b1, kp);
+	i_nround(b1, b0, kp); i_nround(b0, b1, kp);
+	i_nround(b1, b0, kp); i_nround(b0, b1, kp);
+	i_nround(b1, b0, kp); i_nround(b0, b1, kp);
+	i_nround(b1, b0, kp); i_lround(b0, b1, kp);
+
+	out_blk[0] = b0[0]; out_blk[1] = b0[1];
+	out_blk[2] = b0[2]; out_blk[3] = b0[3];
+};