New file.

Rev: src/nettle/sparc/aes-decrypt-internal.asm:1.1

sparc/aes-decrypt-internal.asm

+C -*- mode: asm; asm-comment-char: ?C; -*-  
+C nettle, low-level cryptographics library
+C 
+C Copyright (C) 2002, 2005 Niels Mller
+C  
+C The nettle library is free software; you can redistribute it and/or modify
+C it under the terms of the GNU Lesser General Public License as published by
+C the Free Software Foundation; either version 2.1 of the License, or (at your
+C option) any later version.
+C 
+C The nettle library is distributed in the hope that it will be useful, but
+C WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+C or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+C License for more details.
+C 
+C You should have received a copy of the GNU Lesser General Public License
+C along with the nettle library; see the file COPYING.LIB.  If not, write to
+C the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+C MA 02111-1307, USA.
+
+
+C	Arguments
+define(<CTX>,	<%i0>)
+define(<T>,	<%i1>)
+define(<LENGTH>,<%i2>)
+define(<DST>,	<%i3>)
+define(<SRC>,	<%i4>)
+
+C	AES state, two copies for unrolling
+
+define(<W0>,	<%l0>)
+define(<W1>,	<%l1>)
+define(<W2>,	<%l2>)
+define(<W3>,	<%l3>)
+
+define(<X0>,	<%l4>)
+define(<X1>,	<%l5>)
+define(<X2>,	<%l6>)
+define(<X3>,	<%l7>)
+
+C	%o0-%03 are used for loop invariants T0-T3
+define(<KEY>,	<%o4>)
+define(<ROUND>, <%o5>)
+
+C %g1 and %g2 are TMP1 and TMP2
+		
+
+C Registers %g1-%g3 and %o0 - %o5 are free to use.
+
+C The sparc32 stack frame looks like
+C
+C %fp -   4: OS-dependent link field
+C %fp -   8: OS-dependent link field
+C %fp -  24: tmp, uint32_t[4]
+C %fp -  40: wtxt, uint32_t[4]
+C %fp - 136: OS register save area. 
+define(<FRAME_SIZE>, 136)
+
+	.file "aes-decrypt-internal.asm"
+
+	C _aes_decrypt(struct aes_context *ctx, 
+	C	       const struct aes_table *T,
+	C	       unsigned length, uint8_t *dst,
+	C	       uint8_t *src)
+
+	.section	".text"
+	.align 16
+	.proc	020
+	
+PROLOGUE(_nettle_aes_decrypt)
+
+	save	%sp, -FRAME_SIZE, %sp
+	cmp	LENGTH, 0
+	be	.Lend
+
+	C	Loop invariants
+	add	T, AES_TABLE0, T0
+	add	T, AES_TABLE1, T1
+	add	T, AES_TABLE2, T2
+	add	T, AES_TABLE3, T3
+
+.Lblock_loop:
+	C  Read src, and add initial subkey
+	add	CTX, AES_KEYS, KEY
+	AES_LOAD(0, SRC, KEY, W0)
+	AES_LOAD(1, SRC, KEY, W1)
+	AES_LOAD(2, SRC, KEY, W2)
+	AES_LOAD(3, SRC, KEY, W3)
+
+	C	Must be even, and includes the final round
+	ld	[AES_NROUNDS + CTX], ROUND
+	add	SRC, 16, SRC
+	add	KEY, 16, KEY
+
+	srl	ROUND, 1, ROUND
+	C	Last two rounds handled specially
+	sub	ROUND, 1, ROUND
+.Lround_loop:
+	C The AES_ROUND macro uses T0,... T3
+	C	Transform W -> X
+	AES_ROUND(0, W0, W3, W2, W1, KEY, X0)
+	AES_ROUND(1, W1, W0, W3, W2, KEY, X1)
+	AES_ROUND(2, W2, W1, W0, W3, KEY, X2)
+	AES_ROUND(3, W3, W2, W1, W0, KEY, X3)
+
+	C	Transform X -> W
+	AES_ROUND(4, X0, X3, X2, X1, KEY, W0)
+	AES_ROUND(5, X1, X0, X3, X2, KEY, W1)
+	AES_ROUND(6, X2, X1, X0, X3, KEY, W2)
+	AES_ROUND(7, X3, X2, X1, X0, KEY, W3)
+
+	subcc	ROUND, 1, ROUND
+	bne	.Lround_loop
+	add	KEY, 32, KEY
+
+	C	Penultimate round
+	AES_ROUND(0, W0, W3, W2, W1, KEY, X0)
+	AES_ROUND(1, W1, W0, W3, W2, KEY, X1)
+	AES_ROUND(2, W2, W1, W0, W3, KEY, X2)
+	AES_ROUND(3, W3, W2, W1, W0, KEY, X3)
+
+	add	KEY, 16, KEY
+	C	Final round
+	AES_FINAL_ROUND(0, T, X0, X3, X2, X1, KEY, DST)
+	AES_FINAL_ROUND(1, T, X1, X0, X3, X2, KEY, DST)
+	AES_FINAL_ROUND(2, T, X2, X1, X0, X3, KEY, DST)
+	AES_FINAL_ROUND(3, T, X3, X2, X1, X0, KEY, DST)
+
+	subcc	LENGTH, 16, LENGTH
+	bne	.Lblock_loop
+	add	DST, 16, DST
+
+.Lend:
+	ret
+	restore
+EPILOGUE(_nettle_aes_decrypt)