1 // Copyright 2016 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 #include "textflag.h" 6 7 // func cryptBlocks(c code, key, dst, src *byte, length int) 8 TEXT cryptBlocks(SB),NOSPLIT,$0-40 9 MOVD key+8(FP), R1 10 MOVD dst+16(FP), R2 11 MOVD src+24(FP), R4 12 MOVD length+32(FP), R5 13 MOVD c+0(FP), R0 14 loop: 15 WORD $0xB92E0024 // cipher message (KM) 16 BVS loop // branch back if interrupted 17 XOR R0, R0 18 RET 19 20 // func cryptBlocksChain(c code, iv, key, dst, src *byte, length int) 21 TEXT cryptBlocksChain(SB),NOSPLIT,$48-48 22 LA params-48(SP), R1 23 MOVD iv+8(FP), R8 24 MOVD key+16(FP), R9 25 MVC $16, 0(R8), 0(R1) // move iv into params 26 MVC $32, 0(R9), 16(R1) // move key into params 27 MOVD dst+24(FP), R2 28 MOVD src+32(FP), R4 29 MOVD length+40(FP), R5 30 MOVD c+0(FP), R0 31 loop: 32 WORD $0xB92F0024 // cipher message with chaining (KMC) 33 BVS loop // branch back if interrupted 34 XOR R0, R0 35 MVC $16, 0(R1), 0(R8) // update iv 36 RET 37 38 // func xorBytes(dst, a, b []byte) int 39 TEXT xorBytes(SB),NOSPLIT,$0-80 40 MOVD dst_base+0(FP), R1 41 MOVD a_base+24(FP), R2 42 MOVD b_base+48(FP), R3 43 MOVD a_len+32(FP), R4 44 MOVD b_len+56(FP), R5 45 CMPBLE R4, R5, skip 46 MOVD R5, R4 47 skip: 48 MOVD R4, ret+72(FP) 49 MOVD $0, R5 50 CMPBLT R4, $8, tail 51 loop: 52 MOVD 0(R2)(R5*1), R7 53 MOVD 0(R3)(R5*1), R8 54 XOR R7, R8 55 MOVD R8, 0(R1)(R5*1) 56 LAY 8(R5), R5 57 SUB $8, R4 58 CMPBGE R4, $8, loop 59 tail: 60 CMPBEQ R4, $0, done 61 MOVB 0(R2)(R5*1), R7 62 MOVB 0(R3)(R5*1), R8 63 XOR R7, R8 64 MOVB R8, 0(R1)(R5*1) 65 LAY 1(R5), R5 66 SUB $1, R4 67 BR tail 68 done: 69 RET 70 71 // func cryptBlocksGCM(fn code, key, dst, src, buf []byte, cnt *[16]byte) 72 TEXT cryptBlocksGCM(SB),NOSPLIT,$0-112 73 MOVD src_len+64(FP), R0 74 MOVD buf_base+80(FP), R1 75 MOVD cnt+104(FP), R12 76 LMG (R12), R2, R3 77 78 // Check that the src size is less than or equal to the buffer size. 79 MOVD buf_len+88(FP), R4 80 CMP R0, R4 81 BGT crash 82 83 // Check that the src size is a multiple of 16-bytes. 84 MOVD R0, R4 85 AND $0xf, R4 86 BLT crash // non-zero 87 88 // Check that the src size is less than or equal to the dst size. 89 MOVD dst_len+40(FP), R4 90 CMP R0, R4 91 BGT crash 92 93 MOVD R2, R4 94 MOVD R2, R6 95 MOVD R2, R8 96 MOVD R3, R5 97 MOVD R3, R7 98 MOVD R3, R9 99 ADDW $1, R5 100 ADDW $2, R7 101 ADDW $3, R9 102 incr: 103 CMP R0, $64 104 BLT tail 105 STMG R2, R9, (R1) 106 ADDW $4, R3 107 ADDW $4, R5 108 ADDW $4, R7 109 ADDW $4, R9 110 MOVD $64(R1), R1 111 SUB $64, R0 112 BR incr 113 tail: 114 CMP R0, $0 115 BEQ crypt 116 STMG R2, R3, (R1) 117 ADDW $1, R3 118 MOVD $16(R1), R1 119 SUB $16, R0 120 BR tail 121 crypt: 122 STMG R2, R3, (R12) // update next counter value 123 MOVD fn+0(FP), R0 // function code (encryption) 124 MOVD key_base+8(FP), R1 // key 125 MOVD buf_base+80(FP), R2 // counter values 126 MOVD dst_base+32(FP), R4 // dst 127 MOVD src_base+56(FP), R6 // src 128 MOVD src_len+64(FP), R7 // len 129 loop: 130 WORD $0xB92D2046 // cipher message with counter (KMCTR) 131 BVS loop // branch back if interrupted 132 RET 133 crash: 134 MOVD $0, (R0) 135 RET 136 137 // func ghash(key *gcmHashKey, hash *[16]byte, data []byte) 138 TEXT ghash(SB),NOSPLIT,$32-40 139 MOVD $65, R0 // GHASH function code 140 MOVD key+0(FP), R2 141 LMG (R2), R6, R7 142 MOVD hash+8(FP), R8 143 LMG (R8), R4, R5 144 MOVD $params-32(SP), R1 145 STMG R4, R7, (R1) 146 LMG data+16(FP), R2, R3 // R2=base, R3=len 147 loop: 148 WORD $0xB93E0002 // compute intermediate message digest (KIMD) 149 BVS loop // branch back if interrupted 150 MVC $16, (R1), (R8) 151 MOVD $0, R0 152 RET 153
