[PATCH v3 1/1] snapshot: support tar signature for compressed tar

[list at eworm.de (Christian Hesse)]

From: Christian Hesse <mail at eworm.de>

This adds support for kernel.org style signatures where the uncompressed
tar archive is signed and compressed later. The signature is valid for
all tar* snapshots.

We have a filter which snapshots may be generated and downloaded. This has
to allow tar signatures now even if tar itself is not allowed. To simplify
things we allow all signatures.

Signed-off-by: Christian Hesse <mail at eworm.de>
---
 ui-shared.c   | 12 +++++++++++-
 ui-snapshot.c |  2 +-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/ui-shared.c b/ui-shared.c
index 8a786e0..51a25a0 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -1114,7 +1114,7 @@ void cgit_compose_snapshot_prefix(struct strbuf *filename, const char *base,
 void cgit_print_snapshot_links(const struct cgit_repo *repo, const char *ref,
 			       const char *separator)
 {
-	const struct cgit_snapshot_format* f;
+	const struct cgit_snapshot_format *f, *f_tar;
 	struct strbuf filename = STRBUF_INIT;
 	const char *basename;
 	size_t prefixlen;
@@ -1125,6 +1125,9 @@ void cgit_print_snapshot_links(const struct cgit_repo *repo, const char *ref,
 	else
 		cgit_compose_snapshot_prefix(&filename, basename, ref);
 
+	for (f_tar = cgit_snapshot_formats; strcmp(f_tar->suffix, ".tar") != 0; f_tar++)
+		/* nothing */ ;
+
 	prefixlen = filename.len;
 	for (f = cgit_snapshot_formats; f->suffix; f++) {
 		if (!(repo->snapshots & f->bit))
@@ -1139,6 +1142,13 @@ void cgit_print_snapshot_links(const struct cgit_repo *repo, const char *ref,
 			cgit_snapshot_link("sig", NULL, NULL, NULL, NULL,
 					   filename.buf);
 			html(")");
+		} else if (starts_with(f->suffix, ".tar") && cgit_snapshot_get_sig(ref, f_tar)) {
+			strbuf_setlen(&filename, strlen(filename.buf) - strlen(f->suffix));
+			strbuf_addstr(&filename, ".tar.asc");
+			html(" (");
+			cgit_snapshot_link("sig", NULL, NULL, NULL, NULL,
+					   filename.buf);
+			html(")");
 		}
 		html(separator);
 	}
diff --git a/ui-snapshot.c b/ui-snapshot.c
index c7611e8..76d0573 100644
--- a/ui-snapshot.c
+++ b/ui-snapshot.c
@@ -263,7 +263,7 @@ void cgit_print_snapshot(const char *head, const char *hex,
 	}
 
 	f = get_format(filename);
-	if (!f || !(ctx.repo->snapshots & f->bit)) {
+	if (!f || (!sig_filename && !(ctx.repo->snapshots & f->bit))) {
 		cgit_print_error_page(400, "Bad request",
 				"Unsupported snapshot format: %s", filename);
 		return;