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source: vbox/trunk/src/libs/openssl-1.1.1l/crypto/modes/asm/ghash-armv4.pl@ 91772

Last change on this file since 91772 was 91772, checked in by vboxsync, 3 years ago

openssl-1.1.1l: Applied and adjusted our OpenSSL changes to 1.1.1l. bugref:10126

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1#! /usr/bin/env perl
2# Copyright 2010-2020 The OpenSSL Project Authors. All Rights Reserved.
3#
4# Licensed under the OpenSSL license (the "License"). You may not use
5# this file except in compliance with the License. You can obtain a copy
6# in the file LICENSE in the source distribution or at
7# https://www.openssl.org/source/license.html
8
9#
10# ====================================================================
11# Written by Andy Polyakov <[email protected]> for the OpenSSL
12# project. The module is, however, dual licensed under OpenSSL and
13# CRYPTOGAMS licenses depending on where you obtain it. For further
14# details see http://www.openssl.org/~appro/cryptogams/.
15# ====================================================================
16#
17# April 2010
18#
19# The module implements "4-bit" GCM GHASH function and underlying
20# single multiplication operation in GF(2^128). "4-bit" means that it
21# uses 256 bytes per-key table [+32 bytes shared table]. There is no
22# experimental performance data available yet. The only approximation
23# that can be made at this point is based on code size. Inner loop is
24# 32 instructions long and on single-issue core should execute in <40
25# cycles. Having verified that gcc 3.4 didn't unroll corresponding
26# loop, this assembler loop body was found to be ~3x smaller than
27# compiler-generated one...
28#
29# July 2010
30#
31# Rescheduling for dual-issue pipeline resulted in 8.5% improvement on
32# Cortex A8 core and ~25 cycles per processed byte (which was observed
33# to be ~3 times faster than gcc-generated code:-)
34#
35# February 2011
36#
37# Profiler-assisted and platform-specific optimization resulted in 7%
38# improvement on Cortex A8 core and ~23.5 cycles per byte.
39#
40# March 2011
41#
42# Add NEON implementation featuring polynomial multiplication, i.e. no
43# lookup tables involved. On Cortex A8 it was measured to process one
44# byte in 15 cycles or 55% faster than integer-only code.
45#
46# April 2014
47#
48# Switch to multiplication algorithm suggested in paper referred
49# below and combine it with reduction algorithm from x86 module.
50# Performance improvement over previous version varies from 65% on
51# Snapdragon S4 to 110% on Cortex A9. In absolute terms Cortex A8
52# processes one byte in 8.45 cycles, A9 - in 10.2, A15 - in 7.63,
53# Snapdragon S4 - in 9.33.
54#
55# Câmara, D.; Gouvêa, C. P. L.; López, J. & Dahab, R.: Fast Software
56# Polynomial Multiplication on ARM Processors using the NEON Engine.
57#
58# http://conradoplg.cryptoland.net/files/2010/12/mocrysen13.pdf
59
60# ====================================================================
61# Note about "528B" variant. In ARM case it makes lesser sense to
62# implement it for following reasons:
63#
64# - performance improvement won't be anywhere near 50%, because 128-
65# bit shift operation is neatly fused with 128-bit xor here, and
66# "538B" variant would eliminate only 4-5 instructions out of 32
67# in the inner loop (meaning that estimated improvement is ~15%);
68# - ARM-based systems are often embedded ones and extra memory
69# consumption might be unappreciated (for so little improvement);
70#
71# Byte order [in]dependence. =========================================
72#
73# Caller is expected to maintain specific *dword* order in Htable,
74# namely with *least* significant dword of 128-bit value at *lower*
75# address. This differs completely from C code and has everything to
76# do with ldm instruction and order in which dwords are "consumed" by
77# algorithm. *Byte* order within these dwords in turn is whatever
78# *native* byte order on current platform. See gcm128.c for working
79# example...
80
81$flavour = shift;
82if ($flavour=~/\w[\w\-]*\.\w+$/) { $output=$flavour; undef $flavour; }
83else { while (($output=shift) && ($output!~/\w[\w\-]*\.\w+$/)) {} }
84
85if ($flavour && $flavour ne "void") {
86 $0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
87 ( $xlate="${dir}arm-xlate.pl" and -f $xlate ) or
88 ( $xlate="${dir}../../perlasm/arm-xlate.pl" and -f $xlate) or
89 die "can't locate arm-xlate.pl";
90
91 open STDOUT,"| \"$^X\" $xlate $flavour $output";
92} else {
93 open STDOUT,">$output";
94}
95
96$Xi="r0"; # argument block
97$Htbl="r1";
98$inp="r2";
99$len="r3";
100
101$Zll="r4"; # variables
102$Zlh="r5";
103$Zhl="r6";
104$Zhh="r7";
105$Tll="r8";
106$Tlh="r9";
107$Thl="r10";
108$Thh="r11";
109$nlo="r12";
110################# r13 is stack pointer
111$nhi="r14";
112################# r15 is program counter
113
114$rem_4bit=$inp; # used in gcm_gmult_4bit
115$cnt=$len;
116
117sub Zsmash() {
118 my $i=12;
119 my @args=@_;
120 for ($Zll,$Zlh,$Zhl,$Zhh) {
121 $code.=<<___;
122#if __ARM_ARCH__>=7 && defined(__ARMEL__)
123 rev $_,$_
124 str $_,[$Xi,#$i]
125#elif defined(__ARMEB__)
126 str $_,[$Xi,#$i]
127#else
128 mov $Tlh,$_,lsr#8
129 strb $_,[$Xi,#$i+3]
130 mov $Thl,$_,lsr#16
131 strb $Tlh,[$Xi,#$i+2]
132 mov $Thh,$_,lsr#24
133 strb $Thl,[$Xi,#$i+1]
134 strb $Thh,[$Xi,#$i]
135#endif
136___
137 $code.="\t".shift(@args)."\n";
138 $i-=4;
139 }
140}
141
142$code=<<___;
143#include "arm_arch.h"
144
145.text
146#if defined(__thumb2__) || defined(__clang__)
147.syntax unified
148#define ldrplb ldrbpl
149#define ldrneb ldrbne
150#endif
151#if defined(__thumb2__)
152.thumb
153#else
154.code 32
155#endif
156
157.type rem_4bit,%object
158.align 5
159rem_4bit:
160.short 0x0000,0x1C20,0x3840,0x2460
161.short 0x7080,0x6CA0,0x48C0,0x54E0
162.short 0xE100,0xFD20,0xD940,0xC560
163.short 0x9180,0x8DA0,0xA9C0,0xB5E0
164.size rem_4bit,.-rem_4bit
165
166.type rem_4bit_get,%function
167rem_4bit_get:
168#if defined(__thumb2__)
169 adr $rem_4bit,rem_4bit
170#else
171 sub $rem_4bit,pc,#8+32 @ &rem_4bit
172#endif
173 b .Lrem_4bit_got
174 nop
175 nop
176.size rem_4bit_get,.-rem_4bit_get
177
178.global gcm_ghash_4bit
179.type gcm_ghash_4bit,%function
180.align 4
181gcm_ghash_4bit:
182#if defined(__thumb2__)
183 adr r12,rem_4bit
184#else
185 sub r12,pc,#8+48 @ &rem_4bit
186#endif
187 add $len,$inp,$len @ $len to point at the end
188 stmdb sp!,{r3-r11,lr} @ save $len/end too
189
190 ldmia r12,{r4-r11} @ copy rem_4bit ...
191 stmdb sp!,{r4-r11} @ ... to stack
192
193 ldrb $nlo,[$inp,#15]
194 ldrb $nhi,[$Xi,#15]
195.Louter:
196 eor $nlo,$nlo,$nhi
197 and $nhi,$nlo,#0xf0
198 and $nlo,$nlo,#0x0f
199 mov $cnt,#14
200
201 add $Zhh,$Htbl,$nlo,lsl#4
202 ldmia $Zhh,{$Zll-$Zhh} @ load Htbl[nlo]
203 add $Thh,$Htbl,$nhi
204 ldrb $nlo,[$inp,#14]
205
206 and $nhi,$Zll,#0xf @ rem
207 ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
208 add $nhi,$nhi,$nhi
209 eor $Zll,$Tll,$Zll,lsr#4
210 ldrh $Tll,[sp,$nhi] @ rem_4bit[rem]
211 eor $Zll,$Zll,$Zlh,lsl#28
212 ldrb $nhi,[$Xi,#14]
213 eor $Zlh,$Tlh,$Zlh,lsr#4
214 eor $Zlh,$Zlh,$Zhl,lsl#28
215 eor $Zhl,$Thl,$Zhl,lsr#4
216 eor $Zhl,$Zhl,$Zhh,lsl#28
217 eor $Zhh,$Thh,$Zhh,lsr#4
218 eor $nlo,$nlo,$nhi
219 and $nhi,$nlo,#0xf0
220 and $nlo,$nlo,#0x0f
221 eor $Zhh,$Zhh,$Tll,lsl#16
222
223.Linner:
224 add $Thh,$Htbl,$nlo,lsl#4
225 and $nlo,$Zll,#0xf @ rem
226 subs $cnt,$cnt,#1
227 add $nlo,$nlo,$nlo
228 ldmia $Thh,{$Tll-$Thh} @ load Htbl[nlo]
229 eor $Zll,$Tll,$Zll,lsr#4
230 eor $Zll,$Zll,$Zlh,lsl#28
231 eor $Zlh,$Tlh,$Zlh,lsr#4
232 eor $Zlh,$Zlh,$Zhl,lsl#28
233 ldrh $Tll,[sp,$nlo] @ rem_4bit[rem]
234 eor $Zhl,$Thl,$Zhl,lsr#4
235#ifdef __thumb2__
236 it pl
237#endif
238 ldrplb $nlo,[$inp,$cnt]
239 eor $Zhl,$Zhl,$Zhh,lsl#28
240 eor $Zhh,$Thh,$Zhh,lsr#4
241
242 add $Thh,$Htbl,$nhi
243 and $nhi,$Zll,#0xf @ rem
244 eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
245 add $nhi,$nhi,$nhi
246 ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
247 eor $Zll,$Tll,$Zll,lsr#4
248#ifdef __thumb2__
249 it pl
250#endif
251 ldrplb $Tll,[$Xi,$cnt]
252 eor $Zll,$Zll,$Zlh,lsl#28
253 eor $Zlh,$Tlh,$Zlh,lsr#4
254 ldrh $Tlh,[sp,$nhi]
255 eor $Zlh,$Zlh,$Zhl,lsl#28
256 eor $Zhl,$Thl,$Zhl,lsr#4
257 eor $Zhl,$Zhl,$Zhh,lsl#28
258#ifdef __thumb2__
259 it pl
260#endif
261 eorpl $nlo,$nlo,$Tll
262 eor $Zhh,$Thh,$Zhh,lsr#4
263#ifdef __thumb2__
264 itt pl
265#endif
266 andpl $nhi,$nlo,#0xf0
267 andpl $nlo,$nlo,#0x0f
268 eor $Zhh,$Zhh,$Tlh,lsl#16 @ ^= rem_4bit[rem]
269 bpl .Linner
270
271 ldr $len,[sp,#32] @ re-load $len/end
272 add $inp,$inp,#16
273 mov $nhi,$Zll
274___
275 &Zsmash("cmp\t$inp,$len","\n".
276 "#ifdef __thumb2__\n".
277 " it ne\n".
278 "#endif\n".
279 " ldrneb $nlo,[$inp,#15]");
280$code.=<<___;
281 bne .Louter
282
283 add sp,sp,#36
284#if __ARM_ARCH__>=5
285 ldmia sp!,{r4-r11,pc}
286#else
287 ldmia sp!,{r4-r11,lr}
288 tst lr,#1
289 moveq pc,lr @ be binary compatible with V4, yet
290 bx lr @ interoperable with Thumb ISA:-)
291#endif
292.size gcm_ghash_4bit,.-gcm_ghash_4bit
293
294.global gcm_gmult_4bit
295.type gcm_gmult_4bit,%function
296gcm_gmult_4bit:
297 stmdb sp!,{r4-r11,lr}
298 ldrb $nlo,[$Xi,#15]
299 b rem_4bit_get
300.Lrem_4bit_got:
301 and $nhi,$nlo,#0xf0
302 and $nlo,$nlo,#0x0f
303 mov $cnt,#14
304
305 add $Zhh,$Htbl,$nlo,lsl#4
306 ldmia $Zhh,{$Zll-$Zhh} @ load Htbl[nlo]
307 ldrb $nlo,[$Xi,#14]
308
309 add $Thh,$Htbl,$nhi
310 and $nhi,$Zll,#0xf @ rem
311 ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
312 add $nhi,$nhi,$nhi
313 eor $Zll,$Tll,$Zll,lsr#4
314 ldrh $Tll,[$rem_4bit,$nhi] @ rem_4bit[rem]
315 eor $Zll,$Zll,$Zlh,lsl#28
316 eor $Zlh,$Tlh,$Zlh,lsr#4
317 eor $Zlh,$Zlh,$Zhl,lsl#28
318 eor $Zhl,$Thl,$Zhl,lsr#4
319 eor $Zhl,$Zhl,$Zhh,lsl#28
320 eor $Zhh,$Thh,$Zhh,lsr#4
321 and $nhi,$nlo,#0xf0
322 eor $Zhh,$Zhh,$Tll,lsl#16
323 and $nlo,$nlo,#0x0f
324
325.Loop:
326 add $Thh,$Htbl,$nlo,lsl#4
327 and $nlo,$Zll,#0xf @ rem
328 subs $cnt,$cnt,#1
329 add $nlo,$nlo,$nlo
330 ldmia $Thh,{$Tll-$Thh} @ load Htbl[nlo]
331 eor $Zll,$Tll,$Zll,lsr#4
332 eor $Zll,$Zll,$Zlh,lsl#28
333 eor $Zlh,$Tlh,$Zlh,lsr#4
334 eor $Zlh,$Zlh,$Zhl,lsl#28
335 ldrh $Tll,[$rem_4bit,$nlo] @ rem_4bit[rem]
336 eor $Zhl,$Thl,$Zhl,lsr#4
337#ifdef __thumb2__
338 it pl
339#endif
340 ldrplb $nlo,[$Xi,$cnt]
341 eor $Zhl,$Zhl,$Zhh,lsl#28
342 eor $Zhh,$Thh,$Zhh,lsr#4
343
344 add $Thh,$Htbl,$nhi
345 and $nhi,$Zll,#0xf @ rem
346 eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
347 add $nhi,$nhi,$nhi
348 ldmia $Thh,{$Tll-$Thh} @ load Htbl[nhi]
349 eor $Zll,$Tll,$Zll,lsr#4
350 eor $Zll,$Zll,$Zlh,lsl#28
351 eor $Zlh,$Tlh,$Zlh,lsr#4
352 ldrh $Tll,[$rem_4bit,$nhi] @ rem_4bit[rem]
353 eor $Zlh,$Zlh,$Zhl,lsl#28
354 eor $Zhl,$Thl,$Zhl,lsr#4
355 eor $Zhl,$Zhl,$Zhh,lsl#28
356 eor $Zhh,$Thh,$Zhh,lsr#4
357#ifdef __thumb2__
358 itt pl
359#endif
360 andpl $nhi,$nlo,#0xf0
361 andpl $nlo,$nlo,#0x0f
362 eor $Zhh,$Zhh,$Tll,lsl#16 @ ^= rem_4bit[rem]
363 bpl .Loop
364___
365 &Zsmash();
366$code.=<<___;
367#if __ARM_ARCH__>=5
368 ldmia sp!,{r4-r11,pc}
369#else
370 ldmia sp!,{r4-r11,lr}
371 tst lr,#1
372 moveq pc,lr @ be binary compatible with V4, yet
373 bx lr @ interoperable with Thumb ISA:-)
374#endif
375.size gcm_gmult_4bit,.-gcm_gmult_4bit
376___
377{
378my ($Xl,$Xm,$Xh,$IN)=map("q$_",(0..3));
379my ($t0,$t1,$t2,$t3)=map("q$_",(8..12));
380my ($Hlo,$Hhi,$Hhl,$k48,$k32,$k16)=map("d$_",(26..31));
381
382sub clmul64x64 {
383my ($r,$a,$b)=@_;
384$code.=<<___;
385 vext.8 $t0#lo, $a, $a, #1 @ A1
386 vmull.p8 $t0, $t0#lo, $b @ F = A1*B
387 vext.8 $r#lo, $b, $b, #1 @ B1
388 vmull.p8 $r, $a, $r#lo @ E = A*B1
389 vext.8 $t1#lo, $a, $a, #2 @ A2
390 vmull.p8 $t1, $t1#lo, $b @ H = A2*B
391 vext.8 $t3#lo, $b, $b, #2 @ B2
392 vmull.p8 $t3, $a, $t3#lo @ G = A*B2
393 vext.8 $t2#lo, $a, $a, #3 @ A3
394 veor $t0, $t0, $r @ L = E + F
395 vmull.p8 $t2, $t2#lo, $b @ J = A3*B
396 vext.8 $r#lo, $b, $b, #3 @ B3
397 veor $t1, $t1, $t3 @ M = G + H
398 vmull.p8 $r, $a, $r#lo @ I = A*B3
399 veor $t0#lo, $t0#lo, $t0#hi @ t0 = (L) (P0 + P1) << 8
400 vand $t0#hi, $t0#hi, $k48
401 vext.8 $t3#lo, $b, $b, #4 @ B4
402 veor $t1#lo, $t1#lo, $t1#hi @ t1 = (M) (P2 + P3) << 16
403 vand $t1#hi, $t1#hi, $k32
404 vmull.p8 $t3, $a, $t3#lo @ K = A*B4
405 veor $t2, $t2, $r @ N = I + J
406 veor $t0#lo, $t0#lo, $t0#hi
407 veor $t1#lo, $t1#lo, $t1#hi
408 veor $t2#lo, $t2#lo, $t2#hi @ t2 = (N) (P4 + P5) << 24
409 vand $t2#hi, $t2#hi, $k16
410 vext.8 $t0, $t0, $t0, #15
411 veor $t3#lo, $t3#lo, $t3#hi @ t3 = (K) (P6 + P7) << 32
412 vmov.i64 $t3#hi, #0
413 vext.8 $t1, $t1, $t1, #14
414 veor $t2#lo, $t2#lo, $t2#hi
415 vmull.p8 $r, $a, $b @ D = A*B
416 vext.8 $t3, $t3, $t3, #12
417 vext.8 $t2, $t2, $t2, #13
418 veor $t0, $t0, $t1
419 veor $t2, $t2, $t3
420 veor $r, $r, $t0
421 veor $r, $r, $t2
422___
423}
424
425$code.=<<___;
426#if __ARM_MAX_ARCH__>=7
427.arch armv7-a
428.fpu neon
429
430.global gcm_init_neon
431.type gcm_init_neon,%function
432.align 4
433gcm_init_neon:
434 vld1.64 $IN#hi,[r1]! @ load H
435 vmov.i8 $t0,#0xe1
436 vld1.64 $IN#lo,[r1]
437 vshl.i64 $t0#hi,#57
438 vshr.u64 $t0#lo,#63 @ t0=0xc2....01
439 vdup.8 $t1,$IN#hi[7]
440 vshr.u64 $Hlo,$IN#lo,#63
441 vshr.s8 $t1,#7 @ broadcast carry bit
442 vshl.i64 $IN,$IN,#1
443 vand $t0,$t0,$t1
444 vorr $IN#hi,$Hlo @ H<<<=1
445 veor $IN,$IN,$t0 @ twisted H
446 vstmia r0,{$IN}
447
448 ret @ bx lr
449.size gcm_init_neon,.-gcm_init_neon
450
451.global gcm_gmult_neon
452.type gcm_gmult_neon,%function
453.align 4
454gcm_gmult_neon:
455 vld1.64 $IN#hi,[$Xi]! @ load Xi
456 vld1.64 $IN#lo,[$Xi]!
457 vmov.i64 $k48,#0x0000ffffffffffff
458 vldmia $Htbl,{$Hlo-$Hhi} @ load twisted H
459 vmov.i64 $k32,#0x00000000ffffffff
460#ifdef __ARMEL__
461 vrev64.8 $IN,$IN
462#endif
463 vmov.i64 $k16,#0x000000000000ffff
464 veor $Hhl,$Hlo,$Hhi @ Karatsuba pre-processing
465 mov $len,#16
466 b .Lgmult_neon
467.size gcm_gmult_neon,.-gcm_gmult_neon
468
469.global gcm_ghash_neon
470.type gcm_ghash_neon,%function
471.align 4
472gcm_ghash_neon:
473 vld1.64 $Xl#hi,[$Xi]! @ load Xi
474 vld1.64 $Xl#lo,[$Xi]!
475 vmov.i64 $k48,#0x0000ffffffffffff
476 vldmia $Htbl,{$Hlo-$Hhi} @ load twisted H
477 vmov.i64 $k32,#0x00000000ffffffff
478#ifdef __ARMEL__
479 vrev64.8 $Xl,$Xl
480#endif
481 vmov.i64 $k16,#0x000000000000ffff
482 veor $Hhl,$Hlo,$Hhi @ Karatsuba pre-processing
483
484.Loop_neon:
485 vld1.64 $IN#hi,[$inp]! @ load inp
486 vld1.64 $IN#lo,[$inp]!
487#ifdef __ARMEL__
488 vrev64.8 $IN,$IN
489#endif
490 veor $IN,$Xl @ inp^=Xi
491.Lgmult_neon:
492___
493 &clmul64x64 ($Xl,$Hlo,"$IN#lo"); # H.lo·Xi.lo
494$code.=<<___;
495 veor $IN#lo,$IN#lo,$IN#hi @ Karatsuba pre-processing
496___
497 &clmul64x64 ($Xm,$Hhl,"$IN#lo"); # (H.lo+H.hi)·(Xi.lo+Xi.hi)
498 &clmul64x64 ($Xh,$Hhi,"$IN#hi"); # H.hi·Xi.hi
499$code.=<<___;
500 veor $Xm,$Xm,$Xl @ Karatsuba post-processing
501 veor $Xm,$Xm,$Xh
502 veor $Xl#hi,$Xl#hi,$Xm#lo
503 veor $Xh#lo,$Xh#lo,$Xm#hi @ Xh|Xl - 256-bit result
504
505 @ equivalent of reduction_avx from ghash-x86_64.pl
506 vshl.i64 $t1,$Xl,#57 @ 1st phase
507 vshl.i64 $t2,$Xl,#62
508 veor $t2,$t2,$t1 @
509 vshl.i64 $t1,$Xl,#63
510 veor $t2, $t2, $t1 @
511 veor $Xl#hi,$Xl#hi,$t2#lo @
512 veor $Xh#lo,$Xh#lo,$t2#hi
513
514 vshr.u64 $t2,$Xl,#1 @ 2nd phase
515 veor $Xh,$Xh,$Xl
516 veor $Xl,$Xl,$t2 @
517 vshr.u64 $t2,$t2,#6
518 vshr.u64 $Xl,$Xl,#1 @
519 veor $Xl,$Xl,$Xh @
520 veor $Xl,$Xl,$t2 @
521
522 subs $len,#16
523 bne .Loop_neon
524
525#ifdef __ARMEL__
526 vrev64.8 $Xl,$Xl
527#endif
528 sub $Xi,#16
529 vst1.64 $Xl#hi,[$Xi]! @ write out Xi
530 vst1.64 $Xl#lo,[$Xi]
531
532 ret @ bx lr
533.size gcm_ghash_neon,.-gcm_ghash_neon
534#endif
535___
536}
537$code.=<<___;
538.asciz "GHASH for ARMv4/NEON, CRYPTOGAMS by <appro\@openssl.org>"
539.align 2
540___
541
542foreach (split("\n",$code)) {
543 s/\`([^\`]*)\`/eval $1/geo;
544
545 s/\bq([0-9]+)#(lo|hi)/sprintf "d%d",2*$1+($2 eq "hi")/geo or
546 s/\bret\b/bx lr/go or
547 s/\bbx\s+lr\b/.word\t0xe12fff1e/go; # make it possible to compile with -march=armv4
548
549 print $_,"\n";
550}
551close STDOUT or die "error closing STDOUT: $!"; # enforce flush
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