tests: add test cases for blob parsing

Increasing test coverage.

Signed-off-by: Petr Štetiar <ynezz@true.cz>

1 files changed, 175 insertions, 0 deletions

diff --git a/tests/test-blob-parse.c b/tests/test-blob-parse.c
new file mode 100644
index 0000000..6b1fb56
--- /dev/null
+++ b/tests/test-blob-parse.c
@@ -0,0 +1,175 @@
+/*
+ * Based on certificate dump functionality from ucert.c:
+ *
+ *  Copyright (C) 2018 Daniel Golle <daniel@makrotopia.org>
+ *  SPDX-License-Identifier: GPL-3.0
+ *
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <libgen.h>
+
+#include "blob.h"
+#include "list.h"
+#include "blobmsg_json.h"
+
+#define CERT_BUF_LEN 4096
+
+/*
+ * ucert structure
+ * |               BLOB                    |
+ * |    SIGNATURE    |       PAYLOAD       |
+ * |                 |[ BLOBMSG CONTAINER ]|
+ * |                 |[[T,i,v,e,f,pubkey ]]|
+ */
+enum cert_attr {
+	CERT_ATTR_SIGNATURE,
+	CERT_ATTR_PAYLOAD,
+	CERT_ATTR_MAX
+};
+
+static const struct blob_attr_info cert_policy[CERT_ATTR_MAX] = {
+	[CERT_ATTR_SIGNATURE] = { .type = BLOB_ATTR_BINARY },
+	[CERT_ATTR_PAYLOAD] = { .type = BLOB_ATTR_NESTED },
+};
+
+enum cert_cont_attr {
+	CERT_CT_ATTR_PAYLOAD,
+	CERT_CT_ATTR_MAX
+};
+
+enum cert_payload_attr {
+	CERT_PL_ATTR_CERTTYPE,
+	CERT_PL_ATTR_CERTID,
+	CERT_PL_ATTR_VALIDFROMTIME,
+	CERT_PL_ATTR_EXPIRETIME,
+	CERT_PL_ATTR_PUBKEY,
+	CERT_PL_ATTR_KEY_FINGERPRINT,
+	CERT_PL_ATTR_MAX
+};
+
+enum certtype_id {
+	CERTTYPE_UNSPEC,
+	CERTTYPE_AUTH,
+	CERTTYPE_REVOKE
+};
+
+/* list to store certificate chain at runtime */
+struct cert_object {
+	struct list_head list;
+	struct blob_attr *cert[CERT_ATTR_MAX];
+};
+
+static int cert_load(const char *certfile, struct list_head *chain)
+{
+	FILE *f;
+	struct blob_attr *certtb[CERT_ATTR_MAX];
+	struct blob_attr *bufpt;
+	struct cert_object *cobj;
+	char filebuf[CERT_BUF_LEN];
+	int ret = 0, pret = 0;
+	size_t len, pos = 0;
+
+	f = fopen(certfile, "r");
+	if (!f)
+		return 1;
+
+	len = fread(&filebuf, 1, CERT_BUF_LEN - 1, f);
+	if (len < 64)
+		return 1;
+
+	ret = ferror(f) || !feof(f);
+	fclose(f);
+	if (ret)
+		return 1;
+
+	bufpt = (struct blob_attr *)filebuf;
+	do {
+		pret = blob_parse(bufpt, certtb, cert_policy, CERT_ATTR_MAX);
+		if (pret <= 0)
+			/* no attributes found */
+			break;
+
+		if (pos + blob_pad_len(bufpt) > len)
+			/* blob exceeds filebuffer */
+			break;
+		else
+			pos += blob_pad_len(bufpt);
+
+		if (!certtb[CERT_ATTR_SIGNATURE])
+			/* no signature -> drop */
+			break;
+
+		cobj = calloc(1, sizeof(*cobj));
+		cobj->cert[CERT_ATTR_SIGNATURE] = blob_memdup(certtb[CERT_ATTR_SIGNATURE]);
+		if (certtb[CERT_ATTR_PAYLOAD])
+			cobj->cert[CERT_ATTR_PAYLOAD] = blob_memdup(certtb[CERT_ATTR_PAYLOAD]);
+
+		list_add_tail(&cobj->list, chain);
+		ret += pret;
+	/* repeat parsing while there is still enough remaining data in buffer */
+	} while(len > pos + sizeof(struct blob_attr) && (bufpt = blob_next(bufpt)));
+
+	return (ret <= 0);
+}
+
+/* dump single chain element to console */
+static void cert_dump_blob(struct blob_attr *cert[CERT_ATTR_MAX])
+{
+	int i;
+	char *json = NULL;
+
+	for (i = 0; i < CERT_ATTR_MAX; i++) {
+		struct blob_attr *v = cert[i];
+
+		if (!v)
+			continue;
+
+		switch(cert_policy[i].type) {
+		case BLOB_ATTR_BINARY:
+			fprintf(stdout, "signature:\n---\n%s---\n", (char *) blob_data(v));
+			break;
+		case BLOB_ATTR_NESTED:
+			json = blobmsg_format_json_indent(blob_data(v), false, 0);
+			if (!json)
+				continue;
+
+			fprintf(stdout, "payload:\n---\n%s\n---\n", json);
+			free(json);
+			break;
+		}
+	}
+}
+
+static int cert_dump(const char *certfile)
+{
+	struct cert_object *cobj;
+	static LIST_HEAD(certchain);
+	unsigned int count = 0;
+
+	if (cert_load(certfile, &certchain)) {
+		fprintf(stderr, "cannot parse cert %s\n", basename((char *) certfile));
+		return 1;
+	}
+
+	list_for_each_entry(cobj, &certchain, list) {
+		fprintf(stdout, "=== CHAIN ELEMENT %02u ===\n", ++count);
+		cert_dump_blob(cobj->cert);
+	}
+
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	if (argc != 2) {
+		fprintf(stderr, "Usage: %s <cert.ucert>\n", argv[0]);
+		return 3;
+	}
+
+	cert_dump(argv[1]);
+
+	return 0;
+}