SHA-1 is weak and we need to transition to a new hash function. For
some time, we have referred to this new function as NewHash. Recently,
we decided to pick SHA-256 as NewHash.
Add a basic implementation of SHA-256 based off libtomcrypt, which is in
the public domain. Optimize it and restructure it to meet our coding
standards. Place it in a directory called "sha256" where it and any
future implementations can live so as to avoid a proliferation of
implementation directories.
Wire up SHA-256 in the list of hash algorithms, and add a test that the
algorithm works correctly.
Note that with this patch, it is still not possible to switch to using
SHA-256 in Git. Additional patches are needed to prepare the code to
handle a larger hash algorithm and further test fixes are needed.
Signed-off-by: brian m. carlson <sandals@xxxxxxxxxxxxxxxxxxxx>
---
Makefile | 4 +
cache.h | 12 ++-
hash.h | 19 ++++-
sha1-file.c | 45 +++++++++++
sha256/block/sha256.c | 180 +++++++++++++++++++++++++++++++++++++++++
sha256/block/sha256.h | 26 ++++++
t/helper/test-sha256.c | 7 ++
t/helper/test-tool.c | 1 +
t/helper/test-tool.h | 1 +
t/t0014-hash.sh | 25 ++++++
10 files changed, 316 insertions(+), 4 deletions(-)
create mode 100644 sha256/block/sha256.c
create mode 100644 sha256/block/sha256.h
create mode 100644 t/helper/test-sha256.c
diff --git a/Makefile b/Makefile
index 1c43bf9aa8..76d378c7ba 100644
--- a/Makefile
+++ b/Makefile
@@ -739,6 +739,7 @@ TEST_BUILTINS_OBJS += test-run-command.o
TEST_BUILTINS_OBJS += test-scrap-cache-tree.o
TEST_BUILTINS_OBJS += test-sha1.o
TEST_BUILTINS_OBJS += test-sha1-array.o
+TEST_BUILTINS_OBJS += test-sha256.o
TEST_BUILTINS_OBJS += test-sigchain.o
TEST_BUILTINS_OBJS += test-strcmp-offset.o
TEST_BUILTINS_OBJS += test-string-list.o
@@ -1633,6 +1634,9 @@ endif
endif
endif
+LIB_OBJS += sha256/block/sha256.o
+BASIC_CFLAGS += -DSHA256_BLK
+
ifdef SHA1_MAX_BLOCK_SIZE
LIB_OBJS += compat/sha1-chunked.o
BASIC_CFLAGS += -DSHA1_MAX_BLOCK_SIZE="$(SHA1_MAX_BLOCK_SIZE)"
diff --git a/cache.h b/cache.h
index 48e736b0d5..81ece0360e 100644
--- a/cache.h
+++ b/cache.h
@@ -48,11 +48,17 @@ unsigned long git_deflate_bound(git_zstream *, unsigned long);
/* The block size of SHA-1. */
#define GIT_SHA1_BLKSZ 64
+/* The length in bytes and in hex digits of an object name (SHA-256 value). */
+#define GIT_SHA256_RAWSZ 32
+#define GIT_SHA256_HEXSZ (2 * GIT_SHA256_RAWSZ)
+/* The block size of SHA-256. */
+#define GIT_SHA256_BLKSZ 64
+
/* The length in byte and in hex digits of the largest possible hash value. */
-#define GIT_MAX_RAWSZ GIT_SHA1_RAWSZ
-#define GIT_MAX_HEXSZ GIT_SHA1_HEXSZ
+#define GIT_MAX_RAWSZ GIT_SHA256_RAWSZ
+#define GIT_MAX_HEXSZ GIT_SHA256_HEXSZ
/* The largest possible block size for any supported hash. */
-#define GIT_MAX_BLKSZ GIT_SHA1_BLKSZ
+#define GIT_MAX_BLKSZ GIT_SHA256_BLKSZ
struct object_id {
unsigned char hash[GIT_MAX_RAWSZ];
diff --git a/hash.h b/hash.h
index 46dff69eb3..88d18896d7 100644
--- a/hash.h
+++ b/hash.h
@@ -15,6 +15,8 @@
#include "block-sha1/sha1.h"
#endif
+#include "sha256/block/sha256.h"
+
#ifndef platform_SHA_CTX
/*
* platform's underlying implementation of SHA-1; could be OpenSSL,
@@ -34,6 +36,18 @@
#define git_SHA1_Update platform_SHA1_Update
#define git_SHA1_Final platform_SHA1_Final
+#ifndef platform_SHA256_CTX
+#define platform_SHA256_CTX SHA256_CTX
+#define platform_SHA256_Init SHA256_Init
+#define platform_SHA256_Update SHA256_Update
+#define platform_SHA256_Final SHA256_Final
+#endif
+
+#define git_SHA256_CTX platform_SHA256_CTX
+#define git_SHA256_Init platform_SHA256_Init
+#define git_SHA256_Update platform_SHA256_Update
+#define git_SHA256_Final platform_SHA256_Final
+
#ifdef SHA1_MAX_BLOCK_SIZE
#include "compat/sha1-chunked.h"
#undef git_SHA1_Update
@@ -52,12 +66,15 @@
#define GIT_HASH_UNKNOWN 0
/* SHA-1 */
#define GIT_HASH_SHA1 1
+/* SHA-256 */
+#define GIT_HASH_SHA256 2
/* Number of algorithms supported (including unknown). */
-#define GIT_HASH_NALGOS (GIT_HASH_SHA1 + 1)
+#define GIT_HASH_NALGOS (GIT_HASH_SHA256 + 1)
/* A suitably aligned type for stack allocations of hash contexts. */
union git_hash_ctx {
git_SHA_CTX sha1;
+ git_SHA256_CTX sha256;
};
typedef union git_hash_ctx git_hash_ctx;
diff --git a/sha1-file.c b/sha1-file.c
index 9aadaf0c8d..66ba3dadb9 100644
--- a/sha1-file.c
+++ b/sha1-file.c
@@ -40,10 +40,20 @@
#define EMPTY_TREE_SHA1_BIN_LITERAL \
"\x4b\x82\x5d\xc6\x42\xcb\x6e\xb9\xa0\x60" \
"\xe5\x4b\xf8\xd6\x92\x88\xfb\xee\x49\x04"
+#define EMPTY_TREE_SHA256_BIN_LITERAL \
+ "\x6e\xf1\x9b\x41\x22\x5c\x53\x69\xf1\xc1" \
+ "\x04\xd4\x5d\x8d\x85\xef\xa9\xb0\x57\xb5" \
+ "\x3b\x14\xb4\xb9\xb9\x39\xdd\x74\xde\xcc" \
+ "\x53\x21"
#define EMPTY_BLOB_SHA1_BIN_LITERAL \
"\xe6\x9d\xe2\x9b\xb2\xd1\xd6\x43\x4b\x8b" \
"\x29\xae\x77\x5a\xd8\xc2\xe4\x8c\x53\x91"
+#define EMPTY_BLOB_SHA256_BIN_LITERAL \
+ "\x47\x3a\x0f\x4c\x3b\xe8\xa9\x36\x81\xa2" \
+ "\x67\xe3\xb1\xe9\xa7\xdc\xda\x11\x85\x43" \
+ "\x6f\xe1\x41\xf7\x74\x91\x20\xa3\x03\x72" \
+ "\x18\x13"
const unsigned char null_sha1[GIT_MAX_RAWSZ];
const struct object_id null_oid;
@@ -53,6 +63,12 @@ static const struct object_id empty_tree_oid = {
static const struct object_id empty_blob_oid = {
EMPTY_BLOB_SHA1_BIN_LITERAL
};
+static const struct object_id empty_tree_oid_sha256 = {
+ EMPTY_TREE_SHA256_BIN_LITERAL
+};
+static const struct object_id empty_blob_oid_sha256 = {
+ EMPTY_BLOB_SHA256_BIN_LITERAL
+};
static void git_hash_sha1_init(git_hash_ctx *ctx)
{
@@ -69,6 +85,22 @@ static void git_hash_sha1_final(unsigned char *hash, git_hash_ctx *ctx)
git_SHA1_Final(hash, &ctx->sha1);
}
+
+static void git_hash_sha256_init(git_hash_ctx *ctx)
+{
+ git_SHA256_Init(&ctx->sha256);
+}
+
+static void git_hash_sha256_update(git_hash_ctx *ctx, const void *data, size_t len)
+{
+ git_SHA256_Update(&ctx->sha256, data, len);
+}
+
+static void git_hash_sha256_final(unsigned char *hash, git_hash_ctx *ctx)
+{
+ git_SHA256_Final(hash, &ctx->sha256);
+}
+
static void git_hash_unknown_init(git_hash_ctx *ctx)
{
BUG("trying to init unknown hash");
@@ -110,6 +142,19 @@ const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = {
&empty_tree_oid,
&empty_blob_oid,
},
+ {
+ "sha256",
+ /* "s256", big-endian */
+ 0x73323536,
+ GIT_SHA256_RAWSZ,
+ GIT_SHA256_HEXSZ,
+ GIT_SHA256_BLKSZ,
+ git_hash_sha256_init,
+ git_hash_sha256_update,
+ git_hash_sha256_final,
+ &empty_tree_oid_sha256,
+ &empty_blob_oid_sha256,
+ }
};
const char *empty_tree_oid_hex(void)
diff --git a/sha256/block/sha256.c b/sha256/block/sha256.c
new file mode 100644
index 0000000000..18350c161a
--- /dev/null
+++ b/sha256/block/sha256.c
@@ -0,0 +1,180 @@
+#include "git-compat-util.h"
+#include "./sha256.h"
+
+#define BLKSIZE blk_SHA256_BLKSIZE
+
+void blk_SHA256_Init(blk_SHA256_CTX *ctx)
+{
+ ctx->offset = 0;
+ ctx->length = 0;
+ ctx->state[0] = 0x6A09E667UL;
+ ctx->state[1] = 0xBB67AE85UL;
+ ctx->state[2] = 0x3C6EF372UL;
+ ctx->state[3] = 0xA54FF53AUL;
+ ctx->state[4] = 0x510E527FUL;
+ ctx->state[5] = 0x9B05688CUL;
+ ctx->state[6] = 0x1F83D9ABUL;
+ ctx->state[7] = 0x5BE0CD19UL;
+}
+
+static inline uint32_t ror(uint32_t x, unsigned n)
+{
+ return (x >> n) | (x << (32 - n));
+}
+
+#define Ch(x,y,z) (z ^ (x & (y ^ z)))
+#define Maj(x,y,z) (((x | y) & z) | (x & y))
+#define S(x, n) ror((x),(n))
+#define R(x, n) ((x)>>(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))
+
+static void blk_SHA256_Transform(blk_SHA256_CTX *ctx, const unsigned char *buf)
+{
+
+ uint32_t S[8], W[64], t0, t1;
+ int i;
+
+ /* copy state into S */
+ for (i = 0; i < 8; i++) {
+ S[i] = ctx->state[i];
+ }
+
+ /* copy the state into 512-bits into W[0..15] */
+ for (i = 0; i < 16; i++, buf += sizeof(uint32_t)) {
+ W[i] = get_be32(buf);
+ }
+
+ /* 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];
+ }
+
+#define RND(a,b,c,d,e,f,g,h,i,ki) \
+ t0 = h + Sigma1(e) + Ch(e, f, g) + ki + W[i]; \
+ t1 = Sigma0(a) + Maj(a, b, c); \
+ d += t0; \
+ h = t0 + t1;
+
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],0,0x428a2f98);
+ RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],1,0x71374491);
+ RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],2,0xb5c0fbcf);
+ RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],3,0xe9b5dba5);
+ RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],4,0x3956c25b);
+ RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],5,0x59f111f1);
+ RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],6,0x923f82a4);
+ RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],7,0xab1c5ed5);
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],8,0xd807aa98);
+ RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],9,0x12835b01);
+ RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],10,0x243185be);
+ RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],11,0x550c7dc3);
+ RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],12,0x72be5d74);
+ RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],13,0x80deb1fe);
+ RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],14,0x9bdc06a7);
+ RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],15,0xc19bf174);
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],16,0xe49b69c1);
+ RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],17,0xefbe4786);
+ RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],18,0x0fc19dc6);
+ RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],19,0x240ca1cc);
+ RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],20,0x2de92c6f);
+ RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],21,0x4a7484aa);
+ RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],22,0x5cb0a9dc);
+ RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],23,0x76f988da);
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],24,0x983e5152);
+ RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],25,0xa831c66d);
+ RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],26,0xb00327c8);
+ RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],27,0xbf597fc7);
+ RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],28,0xc6e00bf3);
+ RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],29,0xd5a79147);
+ RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],30,0x06ca6351);
+ RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],31,0x14292967);
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],32,0x27b70a85);
+ RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],33,0x2e1b2138);
+ RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],34,0x4d2c6dfc);
+ RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],35,0x53380d13);
+ RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],36,0x650a7354);
+ RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],37,0x766a0abb);
+ RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],38,0x81c2c92e);
+ RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],39,0x92722c85);
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],40,0xa2bfe8a1);
+ RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],41,0xa81a664b);
+ RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],42,0xc24b8b70);
+ RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],43,0xc76c51a3);
+ RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],44,0xd192e819);
+ RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],45,0xd6990624);
+ RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],46,0xf40e3585);
+ RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],47,0x106aa070);
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],48,0x19a4c116);
+ RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],49,0x1e376c08);
+ RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],50,0x2748774c);
+ RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],51,0x34b0bcb5);
+ RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],52,0x391c0cb3);
+ RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],53,0x4ed8aa4a);
+ RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],54,0x5b9cca4f);
+ RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],55,0x682e6ff3);
+ RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],56,0x748f82ee);
+ RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],57,0x78a5636f);
+ RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],58,0x84c87814);
+ RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],59,0x8cc70208);
+ RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],60,0x90befffa);
+ RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],61,0xa4506ceb);
+ RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],62,0xbef9a3f7);
+ RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],63,0xc67178f2);
+
+#undef RND
+
+ for (i = 0; i < 8; i++) {
+ ctx->state[i] = ctx->state[i] + S[i];
+ }
+}
+
+#define MIN(x, y) ((x) < (y) ? (x) : (y))
+void blk_SHA256_Update(blk_SHA256_CTX *ctx, const void *data, size_t len)
+{
+ const unsigned char *in = data;
+ size_t n;
+ ctx->length += len;
+ while (len > 0) {
+ if (!ctx->offset && len >= BLKSIZE) {
+ blk_SHA256_Transform(ctx, in);
+ in += BLKSIZE;
+ len -= BLKSIZE;
+ } else {
+ n = MIN(len, (BLKSIZE - ctx->offset));
+ memcpy(ctx->buf + ctx->offset, in, n);
+ ctx->offset += n;
+ in += n;
+ len -= n;
+ if (ctx->offset == BLKSIZE) {
+ blk_SHA256_Transform(ctx, ctx->buf);
+ ctx->offset = 0;
+ }
+ }
+ }
+}
+
+void blk_SHA256_Final(unsigned char *digest, blk_SHA256_CTX *ctx)
+{
+ const unsigned trip = BLKSIZE - sizeof(ctx->length);
+ int i;
+
+ ctx->length <<= 3;
+ ctx->buf[ctx->offset++] = 0x80;
+
+ if (ctx->offset > trip) {
+ memset(ctx->buf + ctx->offset, 0, BLKSIZE - ctx->offset);
+ blk_SHA256_Transform(ctx, ctx->buf);
+ ctx->offset = 0;
+ }
+
+ memset(ctx->buf + ctx->offset, 0, BLKSIZE - ctx->offset - sizeof(ctx->length));
+
+ put_be64(ctx->buf + trip, ctx->length);
+ blk_SHA256_Transform(ctx, ctx->buf);
+
+ /* copy output */
+ for (i = 0; i < 8; i++, digest += sizeof(uint32_t))
+ put_be32(digest, ctx->state[i]);
+}
diff --git a/sha256/block/sha256.h b/sha256/block/sha256.h
new file mode 100644
index 0000000000..ad8b178ad3
--- /dev/null
+++ b/sha256/block/sha256.h
@@ -0,0 +1,26 @@
+#ifndef SHA256_BLOCK_SHA256_H
+#define SHA256_BLOCK_SHA256_H
+
+#include "git-compat-util.h"
+
+#define blk_SHA256_BLKSIZE 64
+
+struct blk_SHA256_CTX {
+ uint32_t state[8];
+ uint64_t length;
+ uint32_t offset;
+ uint8_t buf[blk_SHA256_BLKSIZE];
+};
+
+typedef struct blk_SHA256_CTX blk_SHA256_CTX;
+
+void blk_SHA256_Init(blk_SHA256_CTX *ctx);
+void blk_SHA256_Update(blk_SHA256_CTX *ctx, const void *data, size_t len);
+void blk_SHA256_Final(unsigned char *digest, blk_SHA256_CTX *ctx);
+
+#define platform_SHA256_CTX blk_SHA256_CTX
+#define platform_SHA256_Init blk_SHA256_Init
+#define platform_SHA256_Update blk_SHA256_Update
+#define platform_SHA256_Final blk_SHA256_Final
+
+#endif
diff --git a/t/helper/test-sha256.c b/t/helper/test-sha256.c
new file mode 100644
index 0000000000..0ac6a99d5f
--- /dev/null
+++ b/t/helper/test-sha256.c
@@ -0,0 +1,7 @@
+#include "test-tool.h"
+#include "cache.h"
+
+int cmd__sha256(int ac, const char **av)
+{
+ return cmd_hash_impl(ac, av, GIT_HASH_SHA256);
+}
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index e009c8186d..2a65193514 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -43,6 +43,7 @@ static struct test_cmd cmds[] = {
{ "scrap-cache-tree", cmd__scrap_cache_tree },
{ "sha1", cmd__sha1 },
{ "sha1-array", cmd__sha1_array },
+ { "sha256", cmd__sha256 },
{ "sigchain", cmd__sigchain },
{ "strcmp-offset", cmd__strcmp_offset },
{ "string-list", cmd__string_list },
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index 19a7e8332a..2e66a8e47b 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -39,6 +39,7 @@ int cmd__run_command(int argc, const char **argv);
int cmd__scrap_cache_tree(int argc, const char **argv);
int cmd__sha1(int argc, const char **argv);
int cmd__sha1_array(int argc, const char **argv);
+int cmd__sha256(int argc, const char **argv);
int cmd__sigchain(int argc, const char **argv);
int cmd__strcmp_offset(int argc, const char **argv);
int cmd__string_list(int argc, const char **argv);
diff --git a/t/t0014-hash.sh b/t/t0014-hash.sh
index 8e763c2c3d..f8e639743f 100755
--- a/t/t0014-hash.sh
+++ b/t/t0014-hash.sh
@@ -26,4 +26,29 @@ test_expect_success 'test basic SHA-1 hash values' '
grep 4b825dc642cb6eb9a060e54bf8d69288fbee4904 actual
'
+test_expect_success 'test basic SHA-256 hash values' '
+ test-tool sha256 </dev/null >actual &&
+ grep e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 actual &&
+ printf "a" | test-tool sha256 >actual &&
+ grep ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb actual &&
+ printf "abc" | test-tool sha256 >actual &&
+ grep ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad actual &&
+ printf "message digest" | test-tool sha256 >actual &&
+ grep f7846f55cf23e14eebeab5b4e1550cad5b509e3348fbc4efa3a1413d393cb650 actual &&
+ printf "abcdefghijklmnopqrstuvwxyz" | test-tool sha256 >actual &&
+ grep 71c480df93d6ae2f1efad1447c66c9525e316218cf51fc8d9ed832f2daf18b73 actual &&
+ perl -E "for (1..100000) { print q{aaaaaaaaaa}; }" | \
+ test-tool sha256 >actual &&
+ grep cdc76e5c9914fb9281a1c7e284d73e67f1809a48a497200e046d39ccc7112cd0 actual &&
+ perl -E "for (1..100000) { print q{abcdefghijklmnopqrstuvwxyz}; }" | \
+ test-tool sha256 >actual &&
+ grep e406ba321ca712ad35a698bf0af8d61fc4dc40eca6bdcea4697962724ccbde35 actual &&
+ printf "blob 0\0" | test-tool sha256 >actual &&
+ grep 473a0f4c3be8a93681a267e3b1e9a7dcda1185436fe141f7749120a303721813 actual &&
+ printf "blob 3\0abc" | test-tool sha256 >actual &&
+ grep c1cf6e465077930e88dc5136641d402f72a229ddd996f627d60e9639eaba35a6 actual &&
+ printf "tree 0\0" | test-tool sha256 >actual &&
+ grep 6ef19b41225c5369f1c104d45d8d85efa9b057b53b14b4b9b939dd74decc5321 actual
+'
+
test_done
