hash: hash functions operate on byte arrays not git_oids

Separate the concerns of the hash functions from the git_oid functions.
The git_oid structure will need to understand either SHA1 or SHA256; the
hash functions should only deal with the appropriate one of these.

src/commit_graph.c

@@ -230,7 +230,7 @@ int git_commit_graph_file_parse(
 		return commit_graph_error("wrong commit-graph size");
 	git_oid_cpy(&file->checksum, (git_oid *)(data + trailer_offset));
 
-	if (git_hash_buf(&cgraph_checksum, data, (size_t)trailer_offset, GIT_HASH_ALGORITHM_SHA1) < 0)
+	if (git_hash_buf(cgraph_checksum.id, data, (size_t)trailer_offset, GIT_HASH_ALGORITHM_SHA1) < 0)
 		return commit_graph_error("could not calculate signature");
 	if (!git_oid_equal(&cgraph_checksum, &file->checksum))
 		return commit_graph_error("index signature mismatch");
@@ -1132,7 +1132,7 @@ static int commit_graph_write(
 		goto cleanup;
 
 	/* Finalize the checksum and write the trailer. */
-	error = git_hash_final(&cgraph_checksum, &ctx);
+	error = git_hash_final(cgraph_checksum.id, &ctx);
 	if (error < 0)
 		goto cleanup;
 	error = write_cb((const char *)&cgraph_checksum, sizeof(cgraph_checksum), cb_data);

src/config_file.c

@@ -144,7 +144,7 @@ static int config_file_is_modified(int *modified, config_file *file)
 	if ((error = git_futils_readbuffer(&buf, file->path)) < 0)
 		goto out;
 
-	if ((error = git_hash_buf(&hash, buf.ptr, buf.size, GIT_HASH_ALGORITHM_SHA1)) < 0)
+	if ((error = git_hash_buf(hash.id, buf.ptr, buf.size, GIT_HASH_ALGORITHM_SHA1)) < 0)
 		goto out;
 
 	if (!git_oid_equal(&hash, &file->checksum)) {
@@ -869,7 +869,7 @@ static int config_file_read(
 		goto out;
 
 	git_futils_filestamp_set_from_stat(&file->stamp, &st);
-	if ((error = git_hash_buf(&file->checksum, contents.ptr, contents.size, GIT_HASH_ALGORITHM_SHA1)) < 0)
+	if ((error = git_hash_buf(file->checksum.id, contents.ptr, contents.size, GIT_HASH_ALGORITHM_SHA1)) < 0)
 		goto out;
 
 	if ((error = config_file_read_buffer(entries, repo, file, level, depth,

src/diff.c

@@ -269,7 +269,7 @@ static int flush_hunk(git_oid *result, git_hash_ctx *ctx)
 	unsigned short carry = 0;
 	int error, i;
 
-	if ((error = git_hash_final(&hash, ctx)) < 0 ||
+	if ((error = git_hash_final(hash.id, ctx)) < 0 ||
 	    (error = git_hash_init(ctx)) < 0)
 		return error;
 

src/filebuf.c

@@ -397,7 +397,7 @@ int git_filebuf_hash(git_oid *oid, git_filebuf *file)
 	if (verify_last_error(file) < 0)
 		return -1;
 
-	git_hash_final(oid, &file->digest);
+	git_hash_final(oid->id, &file->digest);
 	git_hash_ctx_cleanup(&file->digest);
 	file->compute_digest = 0;
 

src/futils.c

@@ -216,7 +216,7 @@ int git_futils_readbuffer_updated(
 	p_close(fd);
 
 	if (checksum) {
-		if ((error = git_hash_buf(&checksum_new, buf.ptr, buf.size, GIT_HASH_ALGORITHM_SHA1)) < 0) {
+		if ((error = git_hash_buf(checksum_new.id, buf.ptr, buf.size, GIT_HASH_ALGORITHM_SHA1)) < 0) {
 			git_buf_dispose(&buf);
 			return error;
 		}

src/hash.c

@@ -66,7 +66,7 @@ int git_hash_update(git_hash_ctx *ctx, const void *data, size_t len)
 	return -1;
 }
 
-int git_hash_final(git_oid *out, git_hash_ctx *ctx)
+int git_hash_final(unsigned char *out, git_hash_ctx *ctx)
 {
 	switch (ctx->algorithm) {
 	case GIT_HASH_ALGORITHM_SHA1:
@@ -80,7 +80,7 @@ int git_hash_final(git_oid *out, git_hash_ctx *ctx)
 }
 
 int git_hash_buf(
-	git_oid *out,
+	unsigned char *out,
 	const void *data,
 	size_t len,
 	git_hash_algorithm_t algorithm)
@@ -100,7 +100,7 @@ int git_hash_buf(
 }
 
 int git_hash_vec(
-	git_oid *out,
+	unsigned char *out,
 	git_buf_vec *vec,
 	size_t n,
 	git_hash_algorithm_t algorithm)

src/hash.h

@@ -11,6 +11,7 @@
 #include "common.h"
 
 #include "git2/oid.h"
+#include "hash/sha1.h"
 
 typedef struct {
 	void *data;
@@ -22,8 +23,6 @@ typedef enum {
 	GIT_HASH_ALGORITHM_SHA1
 } git_hash_algorithm_t;
 
-#include "hash/sha1.h"
-
 typedef struct git_hash_ctx {
 	union {
 		git_hash_sha1_ctx sha1;
@@ -38,9 +37,9 @@ void git_hash_ctx_cleanup(git_hash_ctx *ctx);
 
 int git_hash_init(git_hash_ctx *c);
 int git_hash_update(git_hash_ctx *c, const void *data, size_t len);
-int git_hash_final(git_oid *out, git_hash_ctx *c);
+int git_hash_final(unsigned char *out, git_hash_ctx *c);
 
-int git_hash_buf(git_oid *out, const void *data, size_t len, git_hash_algorithm_t algorithm);
-int git_hash_vec(git_oid *out, git_buf_vec *vec, size_t n, git_hash_algorithm_t algorithm);
+int git_hash_buf(unsigned char *out, const void *data, size_t len, git_hash_algorithm_t algorithm);
+int git_hash_vec(unsigned char *out, git_buf_vec *vec, size_t n, git_hash_algorithm_t algorithm);
 
 #endif

src/hash/sha1.h

@@ -26,6 +26,8 @@ typedef struct git_hash_sha1_ctx git_hash_sha1_ctx;
 # include "sha1/generic.h"
 #endif
 
+#define GIT_HASH_SHA1_SIZE 20
+
 int git_hash_sha1_global_init(void);
 
 int git_hash_sha1_ctx_init(git_hash_sha1_ctx *ctx);
@@ -33,6 +35,6 @@ void git_hash_sha1_ctx_cleanup(git_hash_sha1_ctx *ctx);
 
 int git_hash_sha1_init(git_hash_sha1_ctx *c);
 int git_hash_sha1_update(git_hash_sha1_ctx *c, const void *data, size_t len);
-int git_hash_sha1_final(git_oid *out, git_hash_sha1_ctx *c);
+int git_hash_sha1_final(unsigned char *out, git_hash_sha1_ctx *c);
 
 #endif

src/hash/sha1/collisiondetect.c

@@ -36,10 +36,10 @@ int git_hash_sha1_update(git_hash_sha1_ctx *ctx, const void *data, size_t len)
 	return 0;
 }
 
-int git_hash_sha1_final(git_oid *out, git_hash_sha1_ctx *ctx)
+int git_hash_sha1_final(unsigned char *out, git_hash_sha1_ctx *ctx)
 {
 	GIT_ASSERT_ARG(ctx);
-	if (SHA1DCFinal(out->id, &ctx->c)) {
+	if (SHA1DCFinal(out, &ctx->c)) {
 		git_error_set(GIT_ERROR_SHA1, "SHA1 collision attack detected");
 		return -1;
 	}

src/hash/sha1/common_crypto.c

@@ -49,9 +49,9 @@ int git_hash_sha1_update(git_hash_sha1_ctx *ctx, const void *_data, size_t len)
 	return 0;
 }
 
-int git_hash_sha1_final(git_oid *out, git_hash_sha1_ctx *ctx)
+int git_hash_sha1_final(unsigned char *out, git_hash_sha1_ctx *ctx)
 {
 	GIT_ASSERT_ARG(ctx);
-	CC_SHA1_Final(out->id, &ctx->c);
+	CC_SHA1_Final(out, &ctx->c);
 	return 0;
 }

src/hash/sha1/generic.c

@@ -278,7 +278,7 @@ int git_hash_sha1_update(git_hash_sha1_ctx *ctx, const void *data, size_t len)
 	return 0;
 }
 
-int git_hash_sha1_final(git_oid *out, git_hash_sha1_ctx *ctx)
+int git_hash_sha1_final(unsigned char *out, git_hash_sha1_ctx *ctx)
 {
 	static const unsigned char pad[64] = { 0x80 };
 	unsigned int padlen[2];
@@ -294,7 +294,7 @@ int git_hash_sha1_final(git_oid *out, git_hash_sha1_ctx *ctx)
 
 	/* Output hash */
 	for (i = 0; i < 5; i++)
-		put_be32(out->id + i*4, ctx->H[i]);
+		put_be32(out + i*4, ctx->H[i]);
 
 	return 0;
 }

src/hash/sha1/mbedtls.c

@@ -38,9 +38,9 @@ int git_hash_sha1_update(git_hash_sha1_ctx *ctx, const void *data, size_t len)
 	return 0;
 }
 
-int git_hash_sha1_final(git_oid *out, git_hash_sha1_ctx *ctx)
+int git_hash_sha1_final(unsigned char *out, git_hash_sha1_ctx *ctx)
 {
 	GIT_ASSERT_ARG(ctx);
-	mbedtls_sha1_finish(&ctx->c, out->id);
+	mbedtls_sha1_finish(&ctx->c, out);
 	return 0;
 }

src/hash/sha1/openssl.c

@@ -46,11 +46,11 @@ int git_hash_sha1_update(git_hash_sha1_ctx *ctx, const void *data, size_t len)
 	return 0;
 }
 
-int git_hash_sha1_final(git_oid *out, git_hash_sha1_ctx *ctx)
+int git_hash_sha1_final(unsigned char *out, git_hash_sha1_ctx *ctx)
 {
 	GIT_ASSERT_ARG(ctx);
 
-	if (SHA1_Final(out->id, &ctx->c) != 1) {
+	if (SHA1_Final(out, &ctx->c) != 1) {
 		git_error_set(GIT_ERROR_SHA1, "hash_openssl: failed to finalize hash");
 		return -1;
 	}

src/hash/sha1/win32.c

@@ -181,14 +181,14 @@ GIT_INLINE(int) hash_cryptoapi_update(git_hash_sha1_ctx *ctx, const void *_data,
 	return 0;
 }
 
-GIT_INLINE(int) hash_cryptoapi_final(git_oid *out, git_hash_sha1_ctx *ctx)
+GIT_INLINE(int) hash_cryptoapi_final(unsigned char *out, git_hash_sha1_ctx *ctx)
 {
-	DWORD len = 20;
+	DWORD len = GIT_HASH_SHA1_SIZE;
 	int error = 0;
 
 	GIT_ASSERT(ctx->ctx.cryptoapi.valid);
 
-	if (!CryptGetHashParam(ctx->ctx.cryptoapi.hash_handle, HP_HASHVAL, out->id, &len, 0)) {
+	if (!CryptGetHashParam(ctx->ctx.cryptoapi.hash_handle, HP_HASHVAL, out, &len, 0)) {
 		git_error_set(GIT_ERROR_OS, "legacy hash data could not be finished");
 		error = -1;
 	}
@@ -262,9 +262,9 @@ GIT_INLINE(int) hash_cng_update(git_hash_sha1_ctx *ctx, const void *_data, size_
 	return 0;
 }
 
-GIT_INLINE(int) hash_cng_final(git_oid *out, git_hash_sha1_ctx *ctx)
+GIT_INLINE(int) hash_cng_final(unsigned char *out, git_hash_sha1_ctx *ctx)
 {
-	if (ctx->prov->prov.cng.finish_hash(ctx->ctx.cng.hash_handle, out->id, GIT_OID_RAWSZ, 0) < 0) {
+	if (ctx->prov->prov.cng.finish_hash(ctx->ctx.cng.hash_handle, out, GIT_HASH_SHA1_SIZE, 0) < 0) {
 		git_error_set(GIT_ERROR_OS, "hash could not be finished");
 		return -1;
 	}
@@ -315,7 +315,7 @@ int git_hash_sha1_update(git_hash_sha1_ctx *ctx, const void *data, size_t len)
 	return (ctx->type == CNG) ? hash_cng_update(ctx, data, len) : hash_cryptoapi_update(ctx, data, len);
 }
 
-int git_hash_sha1_final(git_oid *out, git_hash_sha1_ctx *ctx)
+int git_hash_sha1_final(unsigned char *out, git_hash_sha1_ctx *ctx)
 {
 	GIT_ASSERT_ARG(ctx);
 	GIT_ASSERT_ARG(ctx->type);

src/index.c

@@ -2648,7 +2648,7 @@ static int parse_index(git_index *index, const char *buffer, size_t buffer_size)
 
 	/* Precalculate the SHA1 of the files's contents -- we'll match it to
 	 * the provided SHA1 in the footer */
-	git_hash_buf(&checksum_calculated, buffer, buffer_size - INDEX_FOOTER_SIZE, GIT_HASH_ALGORITHM_SHA1);
+	git_hash_buf(checksum_calculated.id, buffer, buffer_size - INDEX_FOOTER_SIZE, GIT_HASH_ALGORITHM_SHA1);
 
 	/* Parse header */
 	if ((error = read_header(&header, buffer)) < 0)

src/indexer.c

@@ -426,7 +426,7 @@ static int store_object(git_indexer *idx)
 	pentry = git__calloc(1, sizeof(struct git_pack_entry));
 	GIT_ERROR_CHECK_ALLOC(pentry);
 
-	if (git_hash_final(&oid, &idx->hash_ctx)) {
+	if (git_hash_final(oid.id, &idx->hash_ctx)) {
 		git__free(pentry);
 		goto on_error;
 	}
@@ -1183,7 +1183,7 @@ int git_indexer_commit(git_indexer *idx, git_indexer_progress *stats)
 	git_oid_fromraw(&file_hash, packfile_trailer);
 	git_mwindow_close(&w);
 
-	git_hash_final(&trailer_hash, &idx->trailer);
+	git_hash_final(trailer_hash.id, &idx->trailer);
 	if (git_oid_cmp(&file_hash, &trailer_hash)) {
 		git_error_set(GIT_ERROR_INDEXER, "packfile trailer mismatch");
 		return -1;
@@ -1204,7 +1204,7 @@ int git_indexer_commit(git_indexer *idx, git_indexer_progress *stats)
 		if (update_header_and_rehash(idx, stats) < 0)
 			return -1;
 
-		git_hash_final(&trailer_hash, &idx->trailer);
+		git_hash_final(trailer_hash.id, &idx->trailer);
 		write_at(idx, &trailer_hash, idx->pack->mwf.size - GIT_OID_RAWSZ, GIT_OID_RAWSZ);
 	}
 

src/midx.c

@@ -212,7 +212,7 @@ int git_midx_parse(
 		return midx_error("wrong index size");
 	git_oid_cpy(&idx->checksum, (git_oid *)(data + trailer_offset));
 
-	if (git_hash_buf(&idx_checksum, data, (size_t)trailer_offset, GIT_HASH_ALGORITHM_SHA1) < 0)
+	if (git_hash_buf(idx_checksum.id, data, (size_t)trailer_offset, GIT_HASH_ALGORITHM_SHA1) < 0)
 		return midx_error("could not calculate signature");
 	if (!git_oid_equal(&idx_checksum, &idx->checksum))
 		return midx_error("index signature mismatch");
@@ -819,7 +819,7 @@ static int midx_write(
 		goto cleanup;
 
 	/* Finalize the checksum and write the trailer. */
-	error = git_hash_final(&idx_checksum, &ctx);
+	error = git_hash_final(idx_checksum.id, &ctx);
 	if (error < 0)
 		goto cleanup;
 	error = write_cb((const char *)&idx_checksum, sizeof(idx_checksum), cb_data);

src/odb.c

@@ -136,7 +136,7 @@ int git_odb__hashobj(git_oid *id, git_rawobj *obj)
 	vec[1].data = obj->data;
 	vec[1].len = obj->len;
 
-	return git_hash_vec(id, vec, 2, GIT_HASH_ALGORITHM_SHA1);
+	return git_hash_vec(id->id, vec, 2, GIT_HASH_ALGORITHM_SHA1);
 }
 
 
@@ -237,7 +237,7 @@ int git_odb__hashfd(git_oid *out, git_file fd, size_t size, git_object_t type)
 		goto done;
 	}
 
-	error = git_hash_final(out, &ctx);
+	error = git_hash_final(out->id, &ctx);
 
 done:
 	git_hash_ctx_cleanup(&ctx);
@@ -1607,7 +1607,7 @@ int git_odb_stream_finalize_write(git_oid *out, git_odb_stream *stream)
 		return git_odb_stream__invalid_length(stream,
 			"stream_finalize_write()");
 
-	git_hash_final(out, stream->hash_ctx);
+	git_hash_final(out->id, stream->hash_ctx);
 
 	if (git_odb__freshen(stream->backend->odb, out))
 		return 0;

src/pack-objects.c

@@ -664,7 +664,7 @@ static int write_pack(git_packbuilder *pb,
 		pb->nr_remaining -= pb->nr_written;
 	} while (pb->nr_remaining && i < pb->nr_objects);
 
-	if ((error = git_hash_final(&entry_oid, &pb->ctx)) < 0)
+	if ((error = git_hash_final(entry_oid.id, &pb->ctx)) < 0)
 		goto done;
 
 	error = write_cb(entry_oid.id, GIT_OID_RAWSZ, cb_data);

tests/core/sha1.c

@@ -13,7 +13,7 @@ void test_core_sha1__cleanup(void)
 	cl_fixture_cleanup(FIXTURE_DIR);
 }
 
-static int sha1_file(git_oid *oid, const char *filename)
+static int sha1_file(git_oid *out, const char *filename)
 {
 	git_hash_ctx ctx;
 	char buf[2048];
@@ -31,7 +31,7 @@ static int sha1_file(git_oid *oid, const char *filename)
 	cl_assert_equal_i(0, read_len);
 	p_close(fd);
 
-	ret = git_hash_final(oid, &ctx);
+	ret = git_hash_final(out->id, &ctx);
 	git_hash_ctx_cleanup(&ctx);
 
 	return ret;

tests/object/raw/hash.c

@@ -30,14 +30,14 @@ void test_object_raw_hash__hash_by_blocks(void)
 
 	/* should already be init'd */
 	cl_git_pass(git_hash_update(&ctx, hello_text, strlen(hello_text)));
-	cl_git_pass(git_hash_final(&id2, &ctx));
+	cl_git_pass(git_hash_final(id2.id, &ctx));
 	cl_git_pass(git_oid_fromstr(&id1, hello_id));
 	cl_assert(git_oid_cmp(&id1, &id2) == 0);
 
 	/* reinit should permit reuse */
 	cl_git_pass(git_hash_init(&ctx));
 	cl_git_pass(git_hash_update(&ctx, bye_text, strlen(bye_text)));
-	cl_git_pass(git_hash_final(&id2, &ctx));
+	cl_git_pass(git_hash_final(id2.id, &ctx));
 	cl_git_pass(git_oid_fromstr(&id1, bye_id));
 	cl_assert(git_oid_cmp(&id1, &id2) == 0);
 
@@ -49,7 +49,7 @@ void test_object_raw_hash__hash_buffer_in_single_call(void)
 	git_oid id1, id2;
 
 	cl_git_pass(git_oid_fromstr(&id1, hello_id));
-	git_hash_buf(&id2, hello_text, strlen(hello_text), GIT_HASH_ALGORITHM_SHA1);
+	git_hash_buf(id2.id, hello_text, strlen(hello_text), GIT_HASH_ALGORITHM_SHA1);
 	cl_assert(git_oid_cmp(&id1, &id2) == 0);
 }
 
@@ -65,7 +65,7 @@ void test_object_raw_hash__hash_vector(void)
 	vec[1].data = hello_text+4;
 	vec[1].len  = strlen(hello_text)-4;
 
-	git_hash_vec(&id2, vec, 2, GIT_HASH_ALGORITHM_SHA1);
+	git_hash_vec(id2.id, vec, 2, GIT_HASH_ALGORITHM_SHA1);
 
 	cl_assert(git_oid_cmp(&id1, &id2) == 0);
 }

tests/object/raw/short.c

@@ -33,7 +33,7 @@ static int insert_sequential_oids(
 
 	for (i = 0; i < n; ++i) {
 		p_snprintf(numbuf, sizeof(numbuf), "%u", (unsigned int)i);
-		git_hash_buf(&oid, numbuf, strlen(numbuf), GIT_HASH_ALGORITHM_SHA1);
+		git_hash_buf(oid.id, numbuf, strlen(numbuf), GIT_HASH_ALGORITHM_SHA1);
 
 		oids[i] = git__malloc(GIT_OID_HEXSZ + 1);
 		cl_assert(oids[i]);

tests/odb/largefiles.c

@@ -119,7 +119,7 @@ void test_odb_largefiles__streamread(void)
 
 	cl_assert_equal_sz(LARGEFILE_SIZE, total);
 
-	git_hash_final(&read_oid, &hash);
+	git_hash_final(read_oid.id, &hash);
 
 	cl_assert_equal_oid(&oid, &read_oid);
 

tests/pack/packbuilder.c

@@ -128,7 +128,7 @@ void test_pack_packbuilder__create_pack(void)
 
 	cl_git_pass(git_hash_ctx_init(&ctx, GIT_HASH_ALGORITHM_SHA1));
 	cl_git_pass(git_hash_update(&ctx, buf.ptr, buf.size));
-	cl_git_pass(git_hash_final(&hash, &ctx));
+	cl_git_pass(git_hash_final(hash.id, &ctx));
 	git_hash_ctx_cleanup(&ctx);
 
 	git_buf_dispose(&path);