1/* 2 * linux/arch/arm/lib/sha1.S 3 * 4 * SHA transform optimized for ARM 5 * 6 * Copyright: (C) 2005 by Nicolas Pitre <nico@cam.org> 7 * Created: September 17, 2005 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 as 11 * published by the Free Software Foundation. 12 * 13 * The reference implementation for this code is linux/lib/sha1.c 14 */ 15 16#include <linux/linkage.h> 17 18 .text 19 20 21/* 22 * void sha_transform(__u32 *digest, const char *in, __u32 *W) 23 * 24 * Note: the "in" ptr may be unaligned. 25 */ 26 27ENTRY(sha_transform) 28 29 stmfd sp!, {r4 - r8, lr} 30 31 @ for (i = 0; i < 16; i++) 32 @ W[i] = be32_to_cpu(in[i]); 33 34#ifdef __ARMEB__ 35 mov r4, r0 36 mov r0, r2 37 mov r2, #64 38 bl memcpy 39 mov r2, r0 40 mov r0, r4 41#else 42 mov r3, r2 43 mov lr, #16 441: ldrb r4, [r1], #1 45 ldrb r5, [r1], #1 46 ldrb r6, [r1], #1 47 ldrb r7, [r1], #1 48 subs lr, lr, #1 49 orr r5, r5, r4, lsl #8 50 orr r6, r6, r5, lsl #8 51 orr r7, r7, r6, lsl #8 52 str r7, [r3], #4 53 bne 1b 54#endif 55 56 @ for (i = 0; i < 64; i++) 57 @ W[i+16] = ror(W[i+13] ^ W[i+8] ^ W[i+2] ^ W[i], 31); 58 59 sub r3, r2, #4 60 mov lr, #64 612: ldr r4, [r3, #4]! 62 subs lr, lr, #1 63 ldr r5, [r3, #8] 64 ldr r6, [r3, #32] 65 ldr r7, [r3, #52] 66 eor r4, r4, r5 67 eor r4, r4, r6 68 eor r4, r4, r7 69 mov r4, r4, ror #31 70 str r4, [r3, #64] 71 bne 2b 72 73 /* 74 * The SHA functions are: 75 * 76 * f1(B,C,D) = (D ^ (B & (C ^ D))) 77 * f2(B,C,D) = (B ^ C ^ D) 78 * f3(B,C,D) = ((B & C) | (D & (B | C))) 79 * 80 * Then the sub-blocks are processed as follows: 81 * 82 * A' = ror(A, 27) + f(B,C,D) + E + K + *W++ 83 * B' = A 84 * C' = ror(B, 2) 85 * D' = C 86 * E' = D 87 * 88 * We therefore unroll each loop 5 times to avoid register shuffling. 89 * Also the ror for C (and also D and E which are successivelyderived 90 * from it) is applied in place to cut on an additional mov insn for 91 * each round. 92 */ 93 94 .macro sha_f1, A, B, C, D, E 95 ldr r3, [r2], #4 96 eor ip, \C, \D 97 add \E, r1, \E, ror #2 98 and ip, \B, ip, ror #2 99 add \E, \E, \A, ror #27 100 eor ip, ip, \D, ror #2 101 add \E, \E, r3 102 add \E, \E, ip 103 .endm 104 105 .macro sha_f2, A, B, C, D, E 106 ldr r3, [r2], #4 107 add \E, r1, \E, ror #2 108 eor ip, \B, \C, ror #2 109 add \E, \E, \A, ror #27 110 eor ip, ip, \D, ror #2 111 add \E, \E, r3 112 add \E, \E, ip 113 .endm 114 115 .macro sha_f3, A, B, C, D, E 116 ldr r3, [r2], #4 117 add \E, r1, \E, ror #2 118 orr ip, \B, \C, ror #2 119 add \E, \E, \A, ror #27 120 and ip, ip, \D, ror #2 121 add \E, \E, r3 122 and r3, \B, \C, ror #2 123 orr ip, ip, r3 124 add \E, \E, ip 125 .endm 126 127 ldmia r0, {r4 - r8} 128 129 mov lr, #4 130 ldr r1, .L_sha_K + 0 131 132 /* adjust initial values */ 133 mov r6, r6, ror #30 134 mov r7, r7, ror #30 135 mov r8, r8, ror #30 136 1373: subs lr, lr, #1 138 sha_f1 r4, r5, r6, r7, r8 139 sha_f1 r8, r4, r5, r6, r7 140 sha_f1 r7, r8, r4, r5, r6 141 sha_f1 r6, r7, r8, r4, r5 142 sha_f1 r5, r6, r7, r8, r4 143 bne 3b 144 145 ldr r1, .L_sha_K + 4 146 mov lr, #4 147 1484: subs lr, lr, #1 149 sha_f2 r4, r5, r6, r7, r8 150 sha_f2 r8, r4, r5, r6, r7 151 sha_f2 r7, r8, r4, r5, r6 152 sha_f2 r6, r7, r8, r4, r5 153 sha_f2 r5, r6, r7, r8, r4 154 bne 4b 155 156 ldr r1, .L_sha_K + 8 157 mov lr, #4 158 1595: subs lr, lr, #1 160 sha_f3 r4, r5, r6, r7, r8 161 sha_f3 r8, r4, r5, r6, r7 162 sha_f3 r7, r8, r4, r5, r6 163 sha_f3 r6, r7, r8, r4, r5 164 sha_f3 r5, r6, r7, r8, r4 165 bne 5b 166 167 ldr r1, .L_sha_K + 12 168 mov lr, #4 169 1706: subs lr, lr, #1 171 sha_f2 r4, r5, r6, r7, r8 172 sha_f2 r8, r4, r5, r6, r7 173 sha_f2 r7, r8, r4, r5, r6 174 sha_f2 r6, r7, r8, r4, r5 175 sha_f2 r5, r6, r7, r8, r4 176 bne 6b 177 178 ldmia r0, {r1, r2, r3, ip, lr} 179 add r4, r1, r4 180 add r5, r2, r5 181 add r6, r3, r6, ror #2 182 add r7, ip, r7, ror #2 183 add r8, lr, r8, ror #2 184 stmia r0, {r4 - r8} 185 186 ldmfd sp!, {r4 - r8, pc} 187 188ENDPROC(sha_transform) 189 190.L_sha_K: 191 .word 0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6 192 193 194/* 195 * void sha_init(__u32 *buf) 196 */ 197 198.L_sha_initial_digest: 199 .word 0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0 200 201ENTRY(sha_init) 202 203 str lr, [sp, #-4]! 204 adr r1, .L_sha_initial_digest 205 ldmia r1, {r1, r2, r3, ip, lr} 206 stmia r0, {r1, r2, r3, ip, lr} 207 ldr pc, [sp], #4 208 209ENDPROC(sha_init) 210