2 * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20 FILE_LICENCE ( GPL2_OR_LATER );
32 #include <ipxe/rotate.h>
33 #include <ipxe/crypto.h>
34 #include <ipxe/asn1.h>
35 #include <ipxe/sha256.h>
37 /** SHA-256 variables */
38 struct sha256_variables {
39 /* This layout matches that of struct sha256_digest_data,
40 * allowing for efficient endianness-conversion,
51 } __attribute__ (( packed ));
53 /** SHA-256 constants */
54 static const uint32_t k[64] = {
55 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1,
56 0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
57 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786,
58 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
59 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147,
60 0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
61 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b,
62 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
63 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a,
64 0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
65 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
69 * Initialise SHA-256 algorithm
71 * @v ctx SHA-256 context
73 static void sha256_init ( void *ctx ) {
74 struct sha256_context *context = ctx;
76 context->ddd.dd.digest.h[0] = cpu_to_be32 ( 0x6a09e667 );
77 context->ddd.dd.digest.h[1] = cpu_to_be32 ( 0xbb67ae85 );
78 context->ddd.dd.digest.h[2] = cpu_to_be32 ( 0x3c6ef372 );
79 context->ddd.dd.digest.h[3] = cpu_to_be32 ( 0xa54ff53a );
80 context->ddd.dd.digest.h[4] = cpu_to_be32 ( 0x510e527f );
81 context->ddd.dd.digest.h[5] = cpu_to_be32 ( 0x9b05688c );
82 context->ddd.dd.digest.h[6] = cpu_to_be32 ( 0x1f83d9ab );
83 context->ddd.dd.digest.h[7] = cpu_to_be32 ( 0x5be0cd19 );
88 * Calculate SHA-256 digest of accumulated data
90 * @v context SHA-256 context
92 static void sha256_digest ( struct sha256_context *context ) {
94 union sha256_digest_data_dwords ddd;
95 struct sha256_variables v;
100 uint32_t *d = &u.v.d;
101 uint32_t *e = &u.v.e;
102 uint32_t *f = &u.v.f;
103 uint32_t *g = &u.v.g;
104 uint32_t *h = &u.v.h;
115 assert ( ( context->len % sizeof ( context->ddd.dd.data ) ) == 0 );
116 linker_assert ( &u.ddd.dd.digest.h[0] == a, sha256_bad_layout );
117 linker_assert ( &u.ddd.dd.digest.h[1] == b, sha256_bad_layout );
118 linker_assert ( &u.ddd.dd.digest.h[2] == c, sha256_bad_layout );
119 linker_assert ( &u.ddd.dd.digest.h[3] == d, sha256_bad_layout );
120 linker_assert ( &u.ddd.dd.digest.h[4] == e, sha256_bad_layout );
121 linker_assert ( &u.ddd.dd.digest.h[5] == f, sha256_bad_layout );
122 linker_assert ( &u.ddd.dd.digest.h[6] == g, sha256_bad_layout );
123 linker_assert ( &u.ddd.dd.digest.h[7] == h, sha256_bad_layout );
124 linker_assert ( &u.ddd.dd.data.dword[0] == w, sha256_bad_layout );
126 DBGC ( context, "SHA256 digesting:\n" );
127 DBGC_HDA ( context, 0, &context->ddd.dd.digest,
128 sizeof ( context->ddd.dd.digest ) );
129 DBGC_HDA ( context, context->len, &context->ddd.dd.data,
130 sizeof ( context->ddd.dd.data ) );
132 /* Convert h[0..7] to host-endian, and initialise a, b, c, d,
133 * e, f, g, h, and w[0..15]
135 for ( i = 0 ; i < ( sizeof ( u.ddd.dword ) /
136 sizeof ( u.ddd.dword[0] ) ) ; i++ ) {
137 be32_to_cpus ( &context->ddd.dword[i] );
138 u.ddd.dword[i] = context->ddd.dword[i];
141 /* Initialise w[16..63] */
142 for ( i = 16 ; i < 64 ; i++ ) {
143 s0 = ( ror32 ( w[i-15], 7 ) ^ ror32 ( w[i-15], 18 ) ^
145 s1 = ( ror32 ( w[i-2], 17 ) ^ ror32 ( w[i-2], 19 ) ^
147 w[i] = ( w[i-16] + s0 + w[i-7] + s1 );
151 for ( i = 0 ; i < 64 ; i++ ) {
152 s0 = ( ror32 ( *a, 2 ) ^ ror32 ( *a, 13 ) ^ ror32 ( *a, 22 ) );
153 maj = ( ( *a & *b ) ^ ( *a & *c ) ^ ( *b & *c ) );
155 s1 = ( ror32 ( *e, 6 ) ^ ror32 ( *e, 11 ) ^ ror32 ( *e, 25 ) );
156 ch = ( ( *e & *f ) ^ ( (~*e) & *g ) );
157 t1 = ( *h + s1 + ch + k[i] + w[i] );
166 DBGC2 ( context, "%2d : %08x %08x %08x %08x %08x %08x %08x "
167 "%08x\n", i, *a, *b, *c, *d, *e, *f, *g, *h );
170 /* Add chunk to hash and convert back to big-endian */
171 for ( i = 0 ; i < 8 ; i++ ) {
172 context->ddd.dd.digest.h[i] =
173 cpu_to_be32 ( context->ddd.dd.digest.h[i] +
174 u.ddd.dd.digest.h[i] );
177 DBGC ( context, "SHA256 digested:\n" );
178 DBGC_HDA ( context, 0, &context->ddd.dd.digest,
179 sizeof ( context->ddd.dd.digest ) );
183 * Accumulate data with SHA-256 algorithm
185 * @v ctx SHA-256 context
187 * @v len Length of data
189 static void sha256_update ( void *ctx, const void *data, size_t len ) {
190 struct sha256_context *context = ctx;
191 const uint8_t *byte = data;
194 /* Accumulate data a byte at a time, performing the digest
195 * whenever we fill the data buffer
198 offset = ( context->len % sizeof ( context->ddd.dd.data ) );
199 context->ddd.dd.data.byte[offset] = *(byte++);
201 if ( ( context->len % sizeof ( context->ddd.dd.data ) ) == 0 )
202 sha256_digest ( context );
207 * Generate SHA-256 digest
209 * @v ctx SHA-256 context
210 * @v out Output buffer
212 static void sha256_final ( void *ctx, void *out ) {
213 struct sha256_context *context = ctx;
217 /* Record length before pre-processing */
218 len_bits = cpu_to_be64 ( ( ( uint64_t ) context->len ) * 8 );
220 /* Pad with a single "1" bit followed by as many "0" bits as required */
223 sha256_update ( ctx, &pad, sizeof ( pad ) );
225 } while ( ( context->len % sizeof ( context->ddd.dd.data ) ) !=
226 offsetof ( typeof ( context->ddd.dd.data ), final.len ) );
228 /* Append length (in bits) */
229 sha256_update ( ctx, &len_bits, sizeof ( len_bits ) );
230 assert ( ( context->len % sizeof ( context->ddd.dd.data ) ) == 0 );
232 /* Copy out final digest */
233 memcpy ( out, &context->ddd.dd.digest,
234 sizeof ( context->ddd.dd.digest ) );
237 /** SHA-256 algorithm */
238 struct digest_algorithm sha256_algorithm = {
240 .ctxsize = sizeof ( struct sha256_context ),
241 .blocksize = sizeof ( union sha256_block ),
242 .digestsize = sizeof ( struct sha256_digest ),
244 .update = sha256_update,
245 .final = sha256_final,
248 /** "sha256" object identifier */
249 static uint8_t oid_sha256[] = { ASN1_OID_SHA256 };
251 /** "sha256" OID-identified algorithm */
252 struct asn1_algorithm oid_sha256_algorithm __asn1_algorithm = {
254 .digest = &sha256_algorithm,
255 .oid = ASN1_OID_CURSOR ( oid_sha256 ),