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      1 /*
      2  * Based on the Mozilla SHA1 (see mozilla-sha1/sha1.c),
      3  * optimized to do word accesses rather than byte accesses,
      4  * and to avoid unnecessary copies into the context array.
      5  */
      6 
      7 #include <string.h>
      8 #include <arpa/inet.h>
      9 
     10 #include "sha1.h"
     11 
     12 /* Hash one 64-byte block of data */
     13 static void blk_SHA1Block(struct fio_sha1_ctx *ctx, const unsigned int *data);
     14 
     15 void fio_sha1_init(struct fio_sha1_ctx *ctx)
     16 {
     17 	ctx->size = 0;
     18 
     19 	/* Initialize H with the magic constants (see FIPS180 for constants)
     20 	 */
     21 	ctx->H[0] = 0x67452301;
     22 	ctx->H[1] = 0xefcdab89;
     23 	ctx->H[2] = 0x98badcfe;
     24 	ctx->H[3] = 0x10325476;
     25 	ctx->H[4] = 0xc3d2e1f0;
     26 }
     27 
     28 void fio_sha1_update(struct fio_sha1_ctx *ctx, const void *data,
     29 		     unsigned long len)
     30 {
     31 	int lenW = ctx->size & 63;
     32 
     33 	ctx->size += len;
     34 
     35 	/* Read the data into W and process blocks as they get full
     36 	 */
     37 	if (lenW) {
     38 		int left = 64 - lenW;
     39 		if (len < left)
     40 			left = len;
     41 		memcpy(lenW + (char *)ctx->W, data, left);
     42 		lenW = (lenW + left) & 63;
     43 		len -= left;
     44 		data += left;
     45 		if (lenW)
     46 			return;
     47 		blk_SHA1Block(ctx, ctx->W);
     48 	}
     49 	while (len >= 64) {
     50 		blk_SHA1Block(ctx, data);
     51 		data += 64;
     52 		len -= 64;
     53 	}
     54 	if (len)
     55 		memcpy(ctx->W, data, len);
     56 }
     57 
     58 void fio_sha1_final(struct fio_sha1_ctx *ctx)
     59 {
     60 	static const unsigned char pad[64] = { 0x80 };
     61 	unsigned int padlen[2];
     62 	int i;
     63 
     64 	/* Pad with a binary 1 (ie 0x80), then zeroes, then length
     65 	 */
     66 	padlen[0] = htonl(ctx->size >> 29);
     67 	padlen[1] = htonl(ctx->size << 3);
     68 
     69 	i = ctx->size & 63;
     70 	fio_sha1_update(ctx, pad, 1+ (63 & (55 - i)));
     71 	fio_sha1_update(ctx, padlen, 8);
     72 }
     73 
     74 #if defined(__i386__) || defined(__x86_64__)
     75 
     76 #define SHA_ASM(op, x, n) ({ unsigned int __res; __asm__(op " %1,%0":"=r" (__res):"i" (n), "0" (x)); __res; })
     77 #define SHA_ROL(x,n)	SHA_ASM("rol", x, n)
     78 #define SHA_ROR(x,n)	SHA_ASM("ror", x, n)
     79 
     80 #else
     81 
     82 #define SHA_ROT(X,l,r)	(((X) << (l)) | ((X) >> (r)))
     83 #define SHA_ROL(X,n)	SHA_ROT(X,n,32-(n))
     84 #define SHA_ROR(X,n)	SHA_ROT(X,32-(n),n)
     85 
     86 #endif
     87 
     88 /* This "rolls" over the 512-bit array */
     89 #define W(x) (array[(x)&15])
     90 #define setW(x, val) (*(volatile unsigned int *)&W(x) = (val))
     91 
     92 /*
     93  * Where do we get the source from? The first 16 iterations get it from
     94  * the input data, the next mix it from the 512-bit array.
     95  */
     96 #define SHA_SRC(t) htonl(data[t])
     97 #define SHA_MIX(t) SHA_ROL(W(t+13) ^ W(t+8) ^ W(t+2) ^ W(t), 1)
     98 
     99 #define SHA_ROUND(t, input, fn, constant, A, B, C, D, E) do { \
    100 	unsigned int TEMP = input(t); setW(t, TEMP); \
    101 	E += TEMP + SHA_ROL(A,5) + (fn) + (constant); \
    102 	B = SHA_ROR(B, 2); } while (0)
    103 
    104 #define T_0_15(t, A, B, C, D, E)  SHA_ROUND(t, SHA_SRC, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E )
    105 #define T_16_19(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E )
    106 #define T_20_39(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0x6ed9eba1, A, B, C, D, E )
    107 #define T_40_59(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, ((B&C)+(D&(B^C))) , 0x8f1bbcdc, A, B, C, D, E )
    108 #define T_60_79(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) ,  0xca62c1d6, A, B, C, D, E )
    109 
    110 static void blk_SHA1Block(struct fio_sha1_ctx *ctx, const unsigned int *data)
    111 {
    112 	unsigned int A,B,C,D,E;
    113 	unsigned int array[16];
    114 
    115 	A = ctx->H[0];
    116 	B = ctx->H[1];
    117 	C = ctx->H[2];
    118 	D = ctx->H[3];
    119 	E = ctx->H[4];
    120 
    121 	/* Round 1 - iterations 0-16 take their input from 'data' */
    122 	T_0_15( 0, A, B, C, D, E);
    123 	T_0_15( 1, E, A, B, C, D);
    124 	T_0_15( 2, D, E, A, B, C);
    125 	T_0_15( 3, C, D, E, A, B);
    126 	T_0_15( 4, B, C, D, E, A);
    127 	T_0_15( 5, A, B, C, D, E);
    128 	T_0_15( 6, E, A, B, C, D);
    129 	T_0_15( 7, D, E, A, B, C);
    130 	T_0_15( 8, C, D, E, A, B);
    131 	T_0_15( 9, B, C, D, E, A);
    132 	T_0_15(10, A, B, C, D, E);
    133 	T_0_15(11, E, A, B, C, D);
    134 	T_0_15(12, D, E, A, B, C);
    135 	T_0_15(13, C, D, E, A, B);
    136 	T_0_15(14, B, C, D, E, A);
    137 	T_0_15(15, A, B, C, D, E);
    138 
    139 	/* Round 1 - tail. Input from 512-bit mixing array */
    140 	T_16_19(16, E, A, B, C, D);
    141 	T_16_19(17, D, E, A, B, C);
    142 	T_16_19(18, C, D, E, A, B);
    143 	T_16_19(19, B, C, D, E, A);
    144 
    145 	/* Round 2 */
    146 	T_20_39(20, A, B, C, D, E);
    147 	T_20_39(21, E, A, B, C, D);
    148 	T_20_39(22, D, E, A, B, C);
    149 	T_20_39(23, C, D, E, A, B);
    150 	T_20_39(24, B, C, D, E, A);
    151 	T_20_39(25, A, B, C, D, E);
    152 	T_20_39(26, E, A, B, C, D);
    153 	T_20_39(27, D, E, A, B, C);
    154 	T_20_39(28, C, D, E, A, B);
    155 	T_20_39(29, B, C, D, E, A);
    156 	T_20_39(30, A, B, C, D, E);
    157 	T_20_39(31, E, A, B, C, D);
    158 	T_20_39(32, D, E, A, B, C);
    159 	T_20_39(33, C, D, E, A, B);
    160 	T_20_39(34, B, C, D, E, A);
    161 	T_20_39(35, A, B, C, D, E);
    162 	T_20_39(36, E, A, B, C, D);
    163 	T_20_39(37, D, E, A, B, C);
    164 	T_20_39(38, C, D, E, A, B);
    165 	T_20_39(39, B, C, D, E, A);
    166 
    167 	/* Round 3 */
    168 	T_40_59(40, A, B, C, D, E);
    169 	T_40_59(41, E, A, B, C, D);
    170 	T_40_59(42, D, E, A, B, C);
    171 	T_40_59(43, C, D, E, A, B);
    172 	T_40_59(44, B, C, D, E, A);
    173 	T_40_59(45, A, B, C, D, E);
    174 	T_40_59(46, E, A, B, C, D);
    175 	T_40_59(47, D, E, A, B, C);
    176 	T_40_59(48, C, D, E, A, B);
    177 	T_40_59(49, B, C, D, E, A);
    178 	T_40_59(50, A, B, C, D, E);
    179 	T_40_59(51, E, A, B, C, D);
    180 	T_40_59(52, D, E, A, B, C);
    181 	T_40_59(53, C, D, E, A, B);
    182 	T_40_59(54, B, C, D, E, A);
    183 	T_40_59(55, A, B, C, D, E);
    184 	T_40_59(56, E, A, B, C, D);
    185 	T_40_59(57, D, E, A, B, C);
    186 	T_40_59(58, C, D, E, A, B);
    187 	T_40_59(59, B, C, D, E, A);
    188 
    189 	/* Round 4 */
    190 	T_60_79(60, A, B, C, D, E);
    191 	T_60_79(61, E, A, B, C, D);
    192 	T_60_79(62, D, E, A, B, C);
    193 	T_60_79(63, C, D, E, A, B);
    194 	T_60_79(64, B, C, D, E, A);
    195 	T_60_79(65, A, B, C, D, E);
    196 	T_60_79(66, E, A, B, C, D);
    197 	T_60_79(67, D, E, A, B, C);
    198 	T_60_79(68, C, D, E, A, B);
    199 	T_60_79(69, B, C, D, E, A);
    200 	T_60_79(70, A, B, C, D, E);
    201 	T_60_79(71, E, A, B, C, D);
    202 	T_60_79(72, D, E, A, B, C);
    203 	T_60_79(73, C, D, E, A, B);
    204 	T_60_79(74, B, C, D, E, A);
    205 	T_60_79(75, A, B, C, D, E);
    206 	T_60_79(76, E, A, B, C, D);
    207 	T_60_79(77, D, E, A, B, C);
    208 	T_60_79(78, C, D, E, A, B);
    209 	T_60_79(79, B, C, D, E, A);
    210 
    211 	ctx->H[0] += A;
    212 	ctx->H[1] += B;
    213 	ctx->H[2] += C;
    214 	ctx->H[3] += D;
    215 	ctx->H[4] += E;
    216 }
    217