1 files changed, 139 insertions, 0 deletions
diff --git a/src/tools/peer_names.c b/src/tools/peer_names.c
new file mode 100644
index 0000000..37e122d
--- /dev/null
+++ b/src/tools/peer_names.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Luis Ressel <aranea@aixah.de>. All Rights Reserved.
+ */
+
+#include <errno.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "containers.h"
+#include "encoding.h"
+#include "peer_names.h"
+
+static bool parse_peer_name(char *line, struct wgpeer_name *slot)
+{
+	char *name;
+	size_t len;
+
+	name = strpbrk(line, " \t");
+	if (!name)
+		return false;
+	*name = '\0';
+
+	if (!key_from_base64(slot->public_key, line))
+		return false;
+
+	len = strlen(++name);
+	if (name[len - 1] == '\n')
+		name[len - 1] = '\0';
+	slot->name = strdup(name);
+	return !!slot->name;
+}
+
+static int peer_name_cmp(const void *a, const void *b)
+{
+	const struct wgpeer_name *x = a, *y = b;
+	return memcmp(x->public_key, y->public_key, WG_KEY_LEN);
+}
+
+bool peer_names_open(struct wgpeer_names *names, struct wgdevice *device)
+{
+	size_t max_peers = 1, peers = 0, buf_len = 0, path_len;
+	struct wgpeer_name *arr, *arr2;
+	char *buf = NULL, *path;
+	FILE *f;
+
+	path = getenv("WG_PEER_NAMES");
+	if (!path || !path[0]) {
+		errno = 0;
+		return false;
+	}
+
+	path_len = strlen(path);
+	if (path[path_len - 1] == '/') {
+		size_t dev_len = strlen(device->name);
+		char *path2 = malloc(path_len + dev_len + 1);
+
+		if (!path2)
+			return false;
+		memcpy(path2, path, path_len);
+		memcpy(path2 + path_len, device->name, dev_len + 1);
+		f = fopen(path2, "r");
+		free(path2);
+	} else
+		f = fopen(path, "r");
+	if (!f)
+		return false;
+
+	arr = malloc(sizeof(struct wgpeer_name));
+	if (!arr)
+		return false;
+
+	while (getline(&buf, &buf_len, f) >= 0) {
+		if (parse_peer_name(buf, &arr[peers]) && (++peers == max_peers)) {
+			// TODO: Pulled this overflow check out of my ass, gotta revisit it later
+			if (SIZE_MAX / (2 * sizeof(struct wgpeer_name)) < max_peers) {
+				errno = ENOMEM;
+				return false;
+			}
+			max_peers *= 2;
+
+			arr2 = realloc(arr, max_peers * sizeof(struct wgpeer_name));
+			if (!arr2) {
+				free(arr);
+				return false;
+			}
+			arr = arr2;
+		}
+	}
+	free(buf);
+
+	if (!peers)
+		free(arr);
+	if ((arr2 = realloc(arr, peers * sizeof(struct wgpeer_name))))
+		arr = arr2;
+
+	qsort(arr, peers, sizeof(struct wgpeer_name), peer_name_cmp);
+	names->len = peers;
+	names->arr = arr;
+	return true;
+}
+
+void peer_names_free(struct wgpeer_names *names)
+{
+	if (!names)
+		return;
+
+	for (size_t i = 0; i < names->len; ++i)
+		free(names->arr[i].name);
+	if (names->len)
+		free(names->arr);
+}
+
+char *peer_names_get(struct wgpeer_names *names, uint8_t key[static WG_KEY_LEN])
+{
+	size_t r, l = 0;
+
+	if (!names || !names->len)
+		return NULL;
+	r = names->len - 1;
+
+	while (l <= r) {
+		size_t m = l + (r - l) / 2;
+		int cmp = memcmp(key, names->arr[m].public_key, WG_KEY_LEN);
+		if (!cmp)
+			return names->arr[m].name;
+		else if (cmp > 0)
+			l = m + 1;
+		else if (!m)
+			break;
+		else
+			r = m - 1;
+	}
+	return NULL;
+}