From 42d4e1d1128fa1cb56032ac58f65ea3dd1296a9a Mon Sep 17 00:00:00 2001 From: "brian m. carlson" Date: Sat, 22 Feb 2020 20:17:42 +0000 Subject: commit: use expected signature header for SHA-256 The transition plan anticipates that we will allow signatures using multiple algorithms in a single commit. In order to do so, we need to use a different header per algorithm so that it will be obvious over which data to compute the signature. The transition plan specifies that we should use "gpgsig-sha256", so wire up the commit code such that it can write and parse the current algorithm, and it can remove the headers for any algorithm when creating a new commit. Add tests to ensure that we write using the right header and that git fsck doesn't reject these commits. Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano --- commit.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) (limited to 'commit.c') diff --git a/commit.c b/commit.c index a6cfa41a4e..534e14f22a 100644 --- a/commit.c +++ b/commit.c @@ -961,14 +961,22 @@ cleanup_return: return ret; } -static const char gpg_sig_header[] = "gpgsig"; -static const int gpg_sig_header_len = sizeof(gpg_sig_header) - 1; +/* + * Indexed by hash algorithm identifier. + */ +static const char *gpg_sig_headers[] = { + NULL, + "gpgsig", + "gpgsig-sha256", +}; static int do_sign_commit(struct strbuf *buf, const char *keyid) { struct strbuf sig = STRBUF_INIT; int inspos, copypos; const char *eoh; + const char *gpg_sig_header = gpg_sig_headers[hash_algo_by_ptr(the_hash_algo)]; + int gpg_sig_header_len = strlen(gpg_sig_header); /* find the end of the header */ eoh = strstr(buf->buf, "\n\n"); @@ -1010,6 +1018,8 @@ int parse_signed_commit(const struct commit *commit, const char *buffer = get_commit_buffer(commit, &size); int in_signature, saw_signature = -1; const char *line, *tail; + const char *gpg_sig_header = gpg_sig_headers[hash_algo_by_ptr(the_hash_algo)]; + int gpg_sig_header_len = strlen(gpg_sig_header); line = buffer; tail = buffer + size; @@ -1056,11 +1066,17 @@ int remove_signature(struct strbuf *buf) if (in_signature && line[0] == ' ') sig_end = next; - else if (starts_with(line, gpg_sig_header) && - line[gpg_sig_header_len] == ' ') { - sig_start = line; - sig_end = next; - in_signature = 1; + else if (starts_with(line, "gpgsig")) { + int i; + for (i = 1; i < GIT_HASH_NALGOS; i++) { + const char *p; + if (skip_prefix(line, gpg_sig_headers[i], &p) && + *p == ' ') { + sig_start = line; + sig_end = next; + in_signature = 1; + } + } } else { if (*line == '\n') /* dump the whole remainder of the buffer */ -- cgit v1.2.3