1 files changed, 110 insertions, 4 deletions

diff --git a/gpg-interface.c b/gpg-interface.c
index 8b0e87436..3dc2fe397 100644
--- a/gpg-interface.c
+++ b/gpg-interface.c
@@ -7,6 +7,114 @@
 static char *configured_signing_key;
 static const char *gpg_program = "gpg";
 
+#define PGP_SIGNATURE "-----BEGIN PGP SIGNATURE-----"
+#define PGP_MESSAGE "-----BEGIN PGP MESSAGE-----"
+
+void signature_check_clear(struct signature_check *sigc)
+{
+	free(sigc->payload);
+	free(sigc->gpg_output);
+	free(sigc->gpg_status);
+	free(sigc->signer);
+	free(sigc->key);
+	sigc->payload = NULL;
+	sigc->gpg_output = NULL;
+	sigc->gpg_status = NULL;
+	sigc->signer = NULL;
+	sigc->key = NULL;
+}
+
+static struct {
+	char result;
+	const char *check;
+} sigcheck_gpg_status[] = {
+	{ 'G', "\n[GNUPG:] GOODSIG " },
+	{ 'B', "\n[GNUPG:] BADSIG " },
+	{ 'U', "\n[GNUPG:] TRUST_NEVER" },
+	{ 'U', "\n[GNUPG:] TRUST_UNDEFINED" },
+};
+
+void parse_gpg_output(struct signature_check *sigc)
+{
+	const char *buf = sigc->gpg_status;
+	int i;
+
+	/* Iterate over all search strings */
+	for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
+		const char *found, *next;
+
+		if (!skip_prefix(buf, sigcheck_gpg_status[i].check + 1, &found)) {
+			found = strstr(buf, sigcheck_gpg_status[i].check);
+			if (!found)
+				continue;
+			found += strlen(sigcheck_gpg_status[i].check);
+		}
+		sigc->result = sigcheck_gpg_status[i].result;
+		/* The trust messages are not followed by key/signer information */
+		if (sigc->result != 'U') {
+			sigc->key = xmemdupz(found, 16);
+			found += 17;
+			next = strchrnul(found, '\n');
+			sigc->signer = xmemdupz(found, next - found);
+		}
+	}
+}
+
+int check_signature(const char *payload, size_t plen, const char *signature,
+	size_t slen, struct signature_check *sigc)
+{
+	struct strbuf gpg_output = STRBUF_INIT;
+	struct strbuf gpg_status = STRBUF_INIT;
+	int status;
+
+	sigc->result = 'N';
+
+	status = verify_signed_buffer(payload, plen, signature, slen,
+				      &gpg_output, &gpg_status);
+	if (status && !gpg_output.len)
+		goto out;
+	sigc->payload = xmemdupz(payload, plen);
+	sigc->gpg_output = strbuf_detach(&gpg_output, NULL);
+	sigc->gpg_status = strbuf_detach(&gpg_status, NULL);
+	parse_gpg_output(sigc);
+
+ out:
+	strbuf_release(&gpg_status);
+	strbuf_release(&gpg_output);
+
+	return sigc->result != 'G' && sigc->result != 'U';
+}
+
+void print_signature_buffer(const struct signature_check *sigc, unsigned flags)
+{
+	const char *output = flags & GPG_VERIFY_RAW ?
+		sigc->gpg_status : sigc->gpg_output;
+
+	if (flags & GPG_VERIFY_VERBOSE && sigc->payload)
+		fputs(sigc->payload, stdout);
+
+	if (output)
+		fputs(output, stderr);
+}
+
+/*
+ * Look at GPG signed content (e.g. a signed tag object), whose
+ * payload is followed by a detached signature on it.  Return the
+ * offset where the embedded detached signature begins, or the end of
+ * the data when there is no such signature.
+ */
+size_t parse_signature(const char *buf, unsigned long size)
+{
+	char *eol;
+	size_t len = 0;
+	while (len < size && !starts_with(buf + len, PGP_SIGNATURE) &&
+			!starts_with(buf + len, PGP_MESSAGE)) {
+		eol = memchr(buf + len, '\n', size - len);
+		len += eol ? eol - (buf + len) + 1 : size - len;
+	}
+	return len;
+}
+
 void set_signing_key(const char *key)
 {
 	free(configured_signing_key);
@@ -41,12 +149,11 @@ const char *get_signing_key(void)
  */
 int sign_buffer(struct strbuf *buffer, struct strbuf *signature, const char *signing_key)
 {
-	struct child_process gpg;
+	struct child_process gpg = CHILD_PROCESS_INIT;
 	const char *args[4];
 	ssize_t len;
 	size_t i, j, bottom;
 
-	memset(&gpg, 0, sizeof(gpg));
 	gpg.argv = args;
 	gpg.in = -1;
 	gpg.out = -1;
@@ -102,7 +209,7 @@ int verify_signed_buffer(const char *payload, size_t payload_size,
 			 const char *signature, size_t signature_size,
 			 struct strbuf *gpg_output, struct strbuf *gpg_status)
 {
-	struct child_process gpg;
+	struct child_process gpg = CHILD_PROCESS_INIT;
 	const char *args_gpg[] = {NULL, "--status-fd=1", "--verify", "FILE", "-", NULL};
 	char path[PATH_MAX];
 	int fd, ret;
@@ -119,7 +226,6 @@ int verify_signed_buffer(const char *payload, size_t payload_size,
 			     path, strerror(errno));
 	close(fd);
 
-	memset(&gpg, 0, sizeof(gpg));
 	gpg.argv = args_gpg;
 	gpg.in = -1;
 	gpg.out = -1;