[PATCH v3 3/5] erofs-utils: introduce sha256
Gao Xiang
hsiangkao at linux.alibaba.com
Thu Sep 23 04:56:05 AEST 2021
A simple sha256 approach copied from e2fsprogs.
Signed-off-by: Gao Xiang <hsiangkao at linux.alibaba.com>
---
lib/Makefile.am | 2 +-
lib/sha256.c | 248 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 249 insertions(+), 1 deletion(-)
create mode 100644 lib/sha256.c
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 7d00bf5fafdc..2638a109c29c 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -22,7 +22,7 @@ noinst_HEADERS = $(top_srcdir)/include/erofs_fs.h \
noinst_HEADERS += compressor.h
liberofs_la_SOURCES = config.c io.c cache.c super.c inode.c xattr.c exclude.c \
namei.c data.c compress.c compressor.c zmap.c decompress.c \
- compress_hints.c hashmap.c
+ compress_hints.c hashmap.c sha256.c
liberofs_la_CFLAGS = -Wall -Werror -I$(top_srcdir)/include
if ENABLE_LZ4
liberofs_la_CFLAGS += ${LZ4_CFLAGS}
diff --git a/lib/sha256.c b/lib/sha256.c
new file mode 100644
index 000000000000..dd0e058662ff
--- /dev/null
+++ b/lib/sha256.c
@@ -0,0 +1,248 @@
+/*
+ * sha256.c --- The sha256 algorithm
+ *
+ * Copyright (C) 2004 Sam Hocevar <sam at hocevar.net>
+ * (copied from libtomcrypt and then relicensed under GPLv2)
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+#include "erofs/defs.h"
+#include <string.h>
+
+static const __u32 K[64] = {
+ 0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL,
+ 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL,
+ 0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL,
+ 0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
+ 0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL,
+ 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL,
+ 0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL,
+ 0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,
+ 0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL,
+ 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL,
+ 0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL,
+ 0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
+ 0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL
+};
+
+/* Various logical functions */
+#define Ch(x,y,z) (z ^ (x & (y ^ z)))
+#define Maj(x,y,z) (((x | y) & z) | (x & y))
+#define S(x, n) RORc((x),(n))
+#define R(x, n) (((x)&0xFFFFFFFFUL)>>(n))
+#define Sigma0(x) (S(x, 2) ^ S(x, 13) ^ S(x, 22))
+#define Sigma1(x) (S(x, 6) ^ S(x, 11) ^ S(x, 25))
+#define Gamma0(x) (S(x, 7) ^ S(x, 18) ^ R(x, 3))
+#define Gamma1(x) (S(x, 17) ^ S(x, 19) ^ R(x, 10))
+#define RORc(x, y) ( ((((__u32)(x)&0xFFFFFFFFUL)>>(__u32)((y)&31)) | ((__u32)(x)<<(__u32)(32-((y)&31)))) & 0xFFFFFFFFUL)
+
+#define RND(a,b,c,d,e,f,g,h,i) \
+ t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i]; \
+ t1 = Sigma0(a) + Maj(a, b, c); \
+ d += t0; \
+ h = t0 + t1;
+
+#define STORE64H(x, y) \
+ do { \
+ (y)[0] = (unsigned char)(((x)>>56)&255);\
+ (y)[1] = (unsigned char)(((x)>>48)&255);\
+ (y)[2] = (unsigned char)(((x)>>40)&255);\
+ (y)[3] = (unsigned char)(((x)>>32)&255);\
+ (y)[4] = (unsigned char)(((x)>>24)&255);\
+ (y)[5] = (unsigned char)(((x)>>16)&255);\
+ (y)[6] = (unsigned char)(((x)>>8)&255);\
+ (y)[7] = (unsigned char)((x)&255); } while(0)
+
+#define STORE32H(x, y) \
+ do { (y)[0] = (unsigned char)(((x)>>24)&255); (y)[1] = (unsigned char)(((x)>>16)&255); \
+ (y)[2] = (unsigned char)(((x)>>8)&255); (y)[3] = (unsigned char)((x)&255); } while(0)
+
+#define LOAD32H(x, y) \
+ do { x = ((__u32)((y)[0] & 255)<<24) | \
+ ((__u32)((y)[1] & 255)<<16) | \
+ ((__u32)((y)[2] & 255)<<8) | \
+ ((__u32)((y)[3] & 255)); } while(0)
+
+struct sha256_state {
+ __u64 length;
+ __u32 state[8], curlen;
+ unsigned char buf[64];
+};
+
+/* This is a highly simplified version from libtomcrypt */
+struct hash_state {
+ struct sha256_state sha256;
+};
+
+static void sha256_compress(struct hash_state * md, const unsigned char *buf)
+{
+ __u32 S[8], W[64], t0, t1;
+ __u32 t;
+ int i;
+
+ /* copy state into S */
+ for (i = 0; i < 8; i++) {
+ S[i] = md->sha256.state[i];
+ }
+
+ /* copy the state into 512-bits into W[0..15] */
+ for (i = 0; i < 16; i++) {
+ LOAD32H(W[i], buf + (4*i));
+ }
+
+ /* fill W[16..63] */
+ for (i = 16; i < 64; i++) {
+ W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16];
+ }
+
+ /* Compress */
+ for (i = 0; i < 64; ++i) {
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],i);
+ t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4];
+ S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t;
+ }
+
+ /* feedback */
+ for (i = 0; i < 8; i++) {
+ md->sha256.state[i] = md->sha256.state[i] + S[i];
+ }
+}
+
+static void sha256_init(struct hash_state * md)
+{
+ md->sha256.curlen = 0;
+ md->sha256.length = 0;
+ md->sha256.state[0] = 0x6A09E667UL;
+ md->sha256.state[1] = 0xBB67AE85UL;
+ md->sha256.state[2] = 0x3C6EF372UL;
+ md->sha256.state[3] = 0xA54FF53AUL;
+ md->sha256.state[4] = 0x510E527FUL;
+ md->sha256.state[5] = 0x9B05688CUL;
+ md->sha256.state[6] = 0x1F83D9ABUL;
+ md->sha256.state[7] = 0x5BE0CD19UL;
+}
+
+#define MIN(x, y) ( ((x)<(y))?(x):(y) )
+#define SHA256_BLOCKSIZE 64
+static void sha256_process(struct hash_state * md, const unsigned char *in, unsigned long inlen)
+{
+ unsigned long n;
+
+ while (inlen > 0) {
+ if (md->sha256.curlen == 0 && inlen >= SHA256_BLOCKSIZE) {
+ sha256_compress(md, in);
+ md->sha256.length += SHA256_BLOCKSIZE * 8;
+ in += SHA256_BLOCKSIZE;
+ inlen -= SHA256_BLOCKSIZE;
+ } else {
+ n = MIN(inlen, (SHA256_BLOCKSIZE - md->sha256.curlen));
+ memcpy(md->sha256.buf + md->sha256.curlen, in, (size_t)n);
+ md->sha256.curlen += n;
+ in += n;
+ inlen -= n;
+ if (md->sha256.curlen == SHA256_BLOCKSIZE) {
+ sha256_compress(md, md->sha256.buf);
+ md->sha256.length += 8*SHA256_BLOCKSIZE;
+ md->sha256.curlen = 0;
+ }
+ }
+ }
+}
+
+static void sha256_done(struct hash_state * md, unsigned char *out)
+{
+ int i;
+
+ /* increase the length of the message */
+ md->sha256.length += md->sha256.curlen * 8;
+
+ /* append the '1' bit */
+ md->sha256.buf[md->sha256.curlen++] = (unsigned char)0x80;
+
+ /* if the length is currently above 56 bytes we append zeros
+ * then compress. Then we can fall back to padding zeros and length
+ * encoding like normal.
+ */
+ if (md->sha256.curlen > 56) {
+ while (md->sha256.curlen < 64) {
+ md->sha256.buf[md->sha256.curlen++] = (unsigned char)0;
+ }
+ sha256_compress(md, md->sha256.buf);
+ md->sha256.curlen = 0;
+ }
+
+ /* pad upto 56 bytes of zeroes */
+ while (md->sha256.curlen < 56) {
+ md->sha256.buf[md->sha256.curlen++] = (unsigned char)0;
+ }
+
+ /* store length */
+ STORE64H(md->sha256.length, md->sha256.buf+56);
+ sha256_compress(md, md->sha256.buf);
+
+ /* copy output */
+ for (i = 0; i < 8; i++) {
+ STORE32H(md->sha256.state[i], out+(4*i));
+ }
+}
+
+void erofs_sha256(const unsigned char *in, unsigned long in_size,
+ unsigned char out[32])
+{
+ struct hash_state md;
+
+ sha256_init(&md);
+ sha256_process(&md, in, in_size);
+ sha256_done(&md, out);
+}
+
+#ifdef UNITTEST
+static const struct {
+ char *msg;
+ unsigned char hash[32];
+} tests[] = {
+ { "",
+ { 0xe3, 0xb0, 0xc4, 0x42, 0x98, 0xfc, 0x1c, 0x14,
+ 0x9a, 0xfb, 0xf4, 0xc8, 0x99, 0x6f, 0xb9, 0x24,
+ 0x27, 0xae, 0x41, 0xe4, 0x64, 0x9b, 0x93, 0x4c,
+ 0xa4, 0x95, 0x99, 0x1b, 0x78, 0x52, 0xb8, 0x55 }
+ },
+ { "abc",
+ { 0xba, 0x78, 0x16, 0xbf, 0x8f, 0x01, 0xcf, 0xea,
+ 0x41, 0x41, 0x40, 0xde, 0x5d, 0xae, 0x22, 0x23,
+ 0xb0, 0x03, 0x61, 0xa3, 0x96, 0x17, 0x7a, 0x9c,
+ 0xb4, 0x10, 0xff, 0x61, 0xf2, 0x00, 0x15, 0xad }
+ },
+ { "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",
+ { 0x24, 0x8d, 0x6a, 0x61, 0xd2, 0x06, 0x38, 0xb8,
+ 0xe5, 0xc0, 0x26, 0x93, 0x0c, 0x3e, 0x60, 0x39,
+ 0xa3, 0x3c, 0xe4, 0x59, 0x64, 0xff, 0x21, 0x67,
+ 0xf6, 0xec, 0xed, 0xd4, 0x19, 0xdb, 0x06, 0xc1 }
+ },
+};
+
+int main(int argc, char **argv)
+{
+ int i;
+ int errors = 0;
+ unsigned char tmp[32];
+
+ for (i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) {
+ unsigned char *msg = (unsigned char *) tests[i].msg;
+ int len = strlen(tests[i].msg);
+
+ erofs_sha256(msg, len, tmp);
+ printf("SHA256 test message %d: ", i);
+ if (memcmp(tmp, tests[i].hash, 32) != 0) {
+ printf("FAILED\n");
+ errors++;
+ } else
+ printf("OK\n");
+ }
+ return errors;
+}
+
+#endif /* UNITTEST */
--
2.24.4
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