diff options
| -rw-r--r-- | src/libgit2/commit_graph.c | 28 | ||||
| -rw-r--r-- | src/libgit2/commit_graph.h | 3 | ||||
| -rw-r--r-- | tests/libgit2/graph/commitgraph.c | 41 |
3 files changed, 65 insertions, 7 deletions
diff --git a/src/libgit2/commit_graph.c b/src/libgit2/commit_graph.c index 322d24b19..d8da1c5d3 100644 --- a/src/libgit2/commit_graph.c +++ b/src/libgit2/commit_graph.c @@ -201,7 +201,6 @@ int git_commit_graph_file_parse( struct git_commit_graph_chunk *last_chunk; uint32_t i; off64_t last_chunk_offset, chunk_offset, trailer_offset; - unsigned char checksum[GIT_HASH_SHA1_SIZE]; size_t checksum_size; int error; struct git_commit_graph_chunk chunk_oid_fanout = {0}, chunk_oid_lookup = {0}, @@ -234,11 +233,6 @@ int git_commit_graph_file_parse( return commit_graph_error("wrong commit-graph size"); memcpy(file->checksum, (data + trailer_offset), checksum_size); - if (git_hash_buf(checksum, data, (size_t)trailer_offset, GIT_HASH_ALGORITHM_SHA1) < 0) - return commit_graph_error("could not calculate signature"); - if (memcmp(checksum, file->checksum, checksum_size) != 0) - return commit_graph_error("index signature mismatch"); - chunk_hdr = data + sizeof(struct git_commit_graph_header); last_chunk = NULL; for (i = 0; i < hdr->chunks; ++i, chunk_hdr += 12) { @@ -331,9 +325,29 @@ error: return error; } +int git_commit_graph_validate(git_commit_graph *cgraph) { + unsigned char checksum[GIT_HASH_SHA1_SIZE]; + size_t checksum_size = GIT_HASH_SHA1_SIZE; + size_t trailer_offset = cgraph->file->graph_map.len - checksum_size; + + if (cgraph->file->graph_map.len < checksum_size) + return commit_graph_error("map length too small"); + + if (git_hash_buf(checksum, cgraph->file->graph_map.data, trailer_offset, GIT_HASH_ALGORITHM_SHA1) < 0) + return commit_graph_error("could not calculate signature"); + if (memcmp(checksum, cgraph->file->checksum, checksum_size) != 0) + return commit_graph_error("index signature mismatch"); + + return 0; +} + int git_commit_graph_open(git_commit_graph **cgraph_out, const char *objects_dir) { - return git_commit_graph_new(cgraph_out, objects_dir, true); + int error = git_commit_graph_new(cgraph_out, objects_dir, true); + if (!error) { + return git_commit_graph_validate(*cgraph_out); + } + return error; } int git_commit_graph_file_open(git_commit_graph_file **file_out, const char *path) diff --git a/src/libgit2/commit_graph.h b/src/libgit2/commit_graph.h index b78ab8177..517abb239 100644 --- a/src/libgit2/commit_graph.h +++ b/src/libgit2/commit_graph.h @@ -106,6 +106,9 @@ struct git_commit_graph { /** Create a new commit-graph, optionally opening the underlying file. */ int git_commit_graph_new(git_commit_graph **cgraph_out, const char *objects_dir, bool open_file); +/** Validate the checksum of a commit graph */ +int git_commit_graph_validate(git_commit_graph *cgraph); + /** Open and validate a commit-graph file. */ int git_commit_graph_file_open(git_commit_graph_file **file_out, const char *path); diff --git a/tests/libgit2/graph/commitgraph.c b/tests/libgit2/graph/commitgraph.c index e2452000d..82f7f936f 100644 --- a/tests/libgit2/graph/commitgraph.c +++ b/tests/libgit2/graph/commitgraph.c @@ -124,3 +124,44 @@ void test_graph_commitgraph__writer(void) git_commit_graph_writer_free(w); git_repository_free(repo); } + +void test_graph_commitgraph__validate(void) +{ + git_repository *repo; + struct git_commit_graph *cgraph; + git_str objects_dir = GIT_STR_INIT; + + cl_git_pass(git_repository_open(&repo, cl_fixture("testrepo.git"))); + cl_git_pass(git_str_joinpath(&objects_dir, git_repository_path(repo), "objects")); + + /* git_commit_graph_open() calls git_commit_graph_validate() */ + cl_git_pass(git_commit_graph_open(&cgraph, git_str_cstr(&objects_dir))); + + git_commit_graph_free(cgraph); + git_str_dispose(&objects_dir); + git_repository_free(repo); +} + +void test_graph_commitgraph__validate_corrupt(void) +{ + git_repository *repo; + struct git_commit_graph *cgraph; + int fd = -1; + + cl_fixture_sandbox("testrepo.git"); + cl_git_pass(git_repository_open(&repo, cl_git_sandbox_path(1, "testrepo.git", NULL))); + + /* corrupt commit graph checksum at the end of the file */ + cl_assert((fd = p_open(cl_git_sandbox_path(0, "testrepo.git", "objects", "info", "commit-graph", NULL), O_WRONLY)) > 0); + cl_assert(p_lseek(fd, -5, SEEK_END) > 0); + cl_must_pass(p_write(fd, "\0\0", 2)); + cl_must_pass(p_close(fd)); + + /* git_commit_graph_open() calls git_commit_graph_validate() */ + cl_git_fail(git_commit_graph_open(&cgraph, cl_git_sandbox_path(1, "testrepo.git", "objects", NULL))); + + git_commit_graph_free(cgraph); + git_repository_free(repo); + + cl_fixture_cleanup("testrepo.git"); +} |