X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Finvitation.c;h=c008be2ac7a6c7d2cbbca62d1845b040716a723d;hb=0fe69908838248c28624beb540257892db6bdcbd;hp=30d100d98e43ed9d131c0e8264841be0cd1b31c0;hpb=1a52f8093fc2e894860aee82e4a20885099a7130;p=tinc

diff --git a/src/invitation.c b/src/invitation.c
index 30d100d9..c008be2a 100644
--- a/src/invitation.c
+++ b/src/invitation.c
@@ -1,6 +1,6 @@
 /*
     invitation.c -- Create and accept invitations
-    Copyright (C) 2013-2017 Guus Sliepen <guus@tinc-vpn.org>
+    Copyright (C) 2013-2022 Guus Sliepen <guus@tinc-vpn.org>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -34,6 +34,7 @@
 #include "tincctl.h"
 #include "utils.h"
 #include "xalloc.h"
+#include "random.h"
 
 #include "ed25519/sha512.h"
 
@@ -97,7 +98,7 @@ static void scan_for_hostname(const char *filename, char **hostname, char **port
 	fclose(f);
 }
 
-char *get_my_hostname() {
+static char *get_my_hostname(void) {
 	char *hostname = NULL;
 	char *port = NULL;
 	char *hostport = NULL;
@@ -111,6 +112,9 @@ char *get_my_hostname() {
 		scan_for_hostname(tinc_conf, &hostname, &port);
 	}
 
+	free(name);
+	name = NULL;
+
 	if(hostname) {
 		goto done;
 	}
@@ -133,7 +137,7 @@ char *get_my_hostname() {
 
 		if(s >= 0) {
 			send(s, request, sizeof(request) - 1, 0);
-			int len = recv(s, line, sizeof(line) - 1, MSG_WAITALL);
+			ssize_t len = recv(s, line, sizeof(line) - 1, MSG_WAITALL);
 
 			if(len > 0) {
 				line[len] = 0;
@@ -167,7 +171,7 @@ char *get_my_hostname() {
 	// Check that the hostname is reasonable
 	if(hostname) {
 		for(char *p = hostname; *p; p++) {
-			if(isalnum(*p) || *p == '-' || *p == '.' || *p == ':') {
+			if(isalnum((uint8_t) *p) || *p == '-' || *p == '.' || *p == ':') {
 				continue;
 			}
 
@@ -213,7 +217,7 @@ again:
 	}
 
 	for(char *p = line; *p; p++) {
-		if(isalnum(*p) || *p == '-' || *p == '.') {
+		if(isalnum((uint8_t) *p) || *p == '-' || *p == '.') {
 			continue;
 		}
 
@@ -289,6 +293,7 @@ int cmd_invite(int argc, char *argv[]) {
 		return 1;
 	}
 
+	free(myname);
 	myname = get_my_name(true);
 
 	if(!myname) {
@@ -407,6 +412,7 @@ int cmd_invite(int argc, char *argv[]) {
 
 		if(!f) {
 			fprintf(stderr, "Could not write %s: %s\n", filename, strerror(errno));
+			ecdsa_free(key);
 			return 1;
 		}
 
@@ -415,6 +421,7 @@ int cmd_invite(int argc, char *argv[]) {
 		if(!ecdsa_write_pem_private_key(key, f)) {
 			fprintf(stderr, "Could not write ECDSA private key\n");
 			fclose(f);
+			ecdsa_free(key);
 			return 1;
 		}
 
@@ -442,21 +449,27 @@ int cmd_invite(int argc, char *argv[]) {
 	char hash[64];
 	char *fingerprint = ecdsa_get_base64_public_key(key);
 	sha512(fingerprint, strlen(fingerprint), hash);
-	b64encode_urlsafe(hash, hash, 18);
+	b64encode_tinc_urlsafe(hash, hash, 18);
+
+	ecdsa_free(key);
 
 	// Create a random cookie for this invitation.
 	char cookie[25];
 	randomize(cookie, 18);
 
 	// Create a filename that doesn't reveal the cookie itself
-	char buf[18 + strlen(fingerprint)];
+	const size_t buflen = 18 + strlen(fingerprint);
+	uint8_t *buf = alloca(buflen);
+
 	char cookiehash[64];
 	memcpy(buf, cookie, 18);
-	memcpy(buf + 18, fingerprint, sizeof(buf) - 18);
-	sha512(buf, sizeof(buf), cookiehash);
-	b64encode_urlsafe(cookiehash, cookiehash, 18);
+	memcpy(buf + 18, fingerprint, buflen - 18);
+	sha512(buf, buflen, cookiehash);
+	b64encode_tinc_urlsafe(cookiehash, cookiehash, 18);
 
-	b64encode_urlsafe(cookie, cookie, 18);
+	free(fingerprint);
+
+	b64encode_tinc_urlsafe(cookie, cookie, 18);
 
 	// Create a file containing the details of the invitation.
 	snprintf(filename, sizeof(filename), "%s" SLASH "invitations" SLASH "%s", confbase, cookiehash);
@@ -535,15 +548,13 @@ int cmd_invite(int argc, char *argv[]) {
 }
 
 static int sock;
-static char cookie[18];
+static char cookie[18], hash[18];
 static sptps_t sptps;
 static char *data;
 static size_t datalen;
 static bool success = false;
 
-static char cookie[18], hash[18];
-
-static char *get_line(const char **data) {
+static char *get_line(char *line, size_t linelen, const char **data) {
 	if(!data || !*data) {
 		return NULL;
 	}
@@ -553,16 +564,15 @@ static char *get_line(const char **data) {
 		return NULL;
 	}
 
-	static char line[1024];
 	const char *end = strchr(*data, '\n');
 	size_t len = end ? (size_t)(end - *data) : strlen(*data);
 
-	if(len >= sizeof(line)) {
+	if(len >= linelen) {
 		fprintf(stderr, "Maximum line length exceeded!\n");
 		return NULL;
 	}
 
-	if(len && !isprint(**data)) {
+	if(len && !isprint((uint8_t) **data)) {
 		abort();
 	}
 
@@ -579,7 +589,9 @@ static char *get_line(const char **data) {
 }
 
 static char *get_value(const char *data, const char *var) {
-	char *line = get_line(&data);
+	static char buf[1024];
+
+	char *line = get_line(buf, sizeof(buf), &data);
 
 	if(!line) {
 		return NULL;
@@ -605,7 +617,7 @@ static char *grep(const char *data, const char *var) {
 	static char value[1024];
 
 	const char *p = data;
-	int varlen = strlen(var);
+	size_t varlen = strlen(var);
 
 	// Skip all lines not starting with var
 	while(strncasecmp(p, var, varlen) || !strchr(" \t=", p[varlen])) {
@@ -646,25 +658,20 @@ static char *grep(const char *data, const char *var) {
 }
 
 static bool finalize_join(void) {
-	const char *temp_name = get_value(data, "Name");
+	const char *name = get_value(data, "Name");
 
-	if(!temp_name) {
+	if(!name) {
 		fprintf(stderr, "No Name found in invitation!\n");
 		return false;
 	}
 
-	size_t len = strlen(temp_name);
-	char name[len + 1];
-	memcpy(name, temp_name, len);
-	name[len] = 0;
-
 	if(!check_id(name)) {
 		fprintf(stderr, "Invalid Name found in invitation!\n");
 		return false;
 	}
 
 	if(!netname) {
-		netname = grep(data, "NetName");
+		netname = xstrdup(grep(data, "NetName"));
 
 		if(netname && !check_netname(netname, true)) {
 			fprintf(stderr, "Unsafe NetName found in invitation!\n");
@@ -699,7 +706,7 @@ make_names:
 
 		// Generate a random netname, ask for a better one later.
 		ask_netname = true;
-		snprintf(temp_netname, sizeof(temp_netname), "join_%x", rand());
+		snprintf(temp_netname, sizeof(temp_netname), "join_%x", prng(UINT32_MAX));
 		netname = temp_netname;
 		goto make_names;
 	}
@@ -764,14 +771,16 @@ make_names:
 	const char *p = data;
 	char *l, *value;
 
-	while((l = get_line(&p))) {
+	static char line[1024];
+
+	while((l = get_line(line, sizeof(line), &p))) {
 		// Ignore comments
 		if(*l == '#') {
 			continue;
 		}
 
 		// Split line into variable and value
-		int len = strcspn(l, "\t =");
+		size_t len = strcspn(l, "\t =");
 		value = l + len;
 		value += strspn(value, "\t ");
 
@@ -871,12 +880,12 @@ make_names:
 			return false;
 		}
 
-		while((l = get_line(&p))) {
+		while((l = get_line(line, sizeof(line), &p))) {
 			if(!strcmp(l, "#---------------------------------------------------------------#")) {
 				continue;
 			}
 
-			int len = strcspn(l, "\t =");
+			size_t len = strcspn(l, "\t =");
 
 			if(len == 4 && !strncasecmp(l, "Name", 4)) {
 				value = l + len;
@@ -988,7 +997,7 @@ ask_netname:
 	char filename2[PATH_MAX];
 	snprintf(filename, sizeof(filename), "%s" SLASH "tinc-up.invitation", confbase);
 
-#ifdef HAVE_MINGW
+#ifdef HAVE_WINDOWS
 	snprintf(filename2, sizeof(filename2), "%s" SLASH "tinc-up.bat", confbase);
 #else
 	snprintf(filename2, sizeof(filename2), "%s" SLASH "tinc-up", confbase);
@@ -1020,7 +1029,7 @@ ask_netname:
 
 				if(response == 'e') {
 					char *command;
-#ifndef HAVE_MINGW
+#ifndef HAVE_WINDOWS
 					const char *editor = getenv("VISUAL");
 
 					if(!editor) {
@@ -1054,7 +1063,13 @@ ask_netname:
 				}
 			}
 		} else {
-			fprintf(stderr, "A tinc-up script was generated, but has been left disabled.\n");
+			if(force) {
+				rename(filename, filename2);
+				chmod(filename2, 0755);
+				fprintf(stderr, "tinc-up enabled.\n");
+			} else {
+				fprintf(stderr, "A tinc-up script was generated, but has been left disabled.\n");
+			}
 		}
 	} else {
 		// A placeholder was generated.
@@ -1074,7 +1089,7 @@ static bool invitation_send(void *handle, uint8_t type, const void *vdata, size_
 	const char *data = vdata;
 
 	while(len) {
-		int result = send(sock, data, len, 0);
+		ssize_t result = send(sock, data, len, 0);
 
 		if(result == -1 && sockwouldblock(sockerrno)) {
 			continue;
@@ -1211,10 +1226,11 @@ int cmd_join(int argc, char *argv[]) {
 	}
 
 	if(!port || !*port) {
-		port = "655";
+		static char default_port[] = "655";
+		port = default_port;
 	}
 
-	if(!b64decode(slash, hash, 24) || !b64decode(slash + 24, cookie, 24)) {
+	if(!b64decode_tinc(slash, hash, 24) || !b64decode_tinc(slash + 24, cookie, 24)) {
 		goto invalid;
 	}
 
@@ -1231,6 +1247,8 @@ int cmd_join(int argc, char *argv[]) {
 	struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
 
 	if(!ai) {
+		free(b64key);
+		ecdsa_free(key);
 		return 1;
 	}
 
@@ -1244,6 +1262,8 @@ next:
 
 		if(!aip) {
 			freeaddrinfo(ai);
+			free(b64key);
+			ecdsa_free(key);
 			return 1;
 		}
 	}
@@ -1268,7 +1288,7 @@ next:
 	fprintf(stderr, "Connected to %s port %s...\n", address, port);
 
 	// Tell him we have an invitation, and give him our throw-away key.
-	int len = snprintf(line, sizeof(line), "0 ?%s %d.%d\n", b64key, PROT_MAJOR, PROT_MINOR);
+	ssize_t len = snprintf(line, sizeof(line), "0 ?%s %d.%d\n", b64key, PROT_MAJOR, PROT_MINOR);
 
 	if(len <= 0 || (size_t)len >= sizeof(line)) {
 		abort();
@@ -1290,6 +1310,11 @@ next:
 	}
 
 	freeaddrinfo(ai);
+	ai = NULL;
+	aip = NULL;
+
+	free(b64key);
+	b64key = NULL;
 
 	// Check if the hash of the key he gave us matches the hash in the URL.
 	char *fingerprint = line + 2;
@@ -1297,11 +1322,13 @@ next:
 
 	if(sha512(fingerprint, strlen(fingerprint), hishash)) {
 		fprintf(stderr, "Could not create digest\n%s\n", line + 2);
+		ecdsa_free(key);
 		return 1;
 	}
 
 	if(memcmp(hishash, hash, 18)) {
 		fprintf(stderr, "Peer has an invalid key!\n%s\n", line + 2);
+		ecdsa_free(key);
 		return 1;
 
 	}
@@ -1309,17 +1336,21 @@ next:
 	ecdsa_t *hiskey = ecdsa_set_base64_public_key(fingerprint);
 
 	if(!hiskey) {
+		ecdsa_free(key);
 		return 1;
 	}
 
 	// Start an SPTPS session
 	if(!sptps_start(&sptps, NULL, true, false, key, hiskey, "tinc invitation", 15, invitation_send, invitation_receive)) {
+		ecdsa_free(hiskey);
+		ecdsa_free(key);
 		return 1;
 	}
 
 	// Feed rest of input buffer to SPTPS
 	if(!sptps_receive_data(&sptps, buffer, blen)) {
-		return 1;
+		success = false;
+		goto exit;
 	}
 
 	while((len = recv(sock, line, sizeof(line), 0))) {
@@ -1328,7 +1359,7 @@ next:
 				continue;
 			}
 
-#if HAVE_MINGW
+#if HAVE_WINDOWS
 
 			// If socket has been shut down, recv() on Windows returns -1 and sets sockerrno
 			// to WSAESHUTDOWN, while on UNIX-like operating systems recv() returns 0, so we
@@ -1339,30 +1370,33 @@ next:
 
 #endif
 			fprintf(stderr, "Error reading data from %s port %s: %s\n", address, port, sockstrerror(sockerrno));
-			return 1;
+			success = false;
+			goto exit;
 		}
 
 		char *p = line;
 
 		while(len) {
-			int done = sptps_receive_data(&sptps, p, len);
+			size_t done = sptps_receive_data(&sptps, p, len);
 
 			if(!done) {
-				return 1;
+				success = false;
+				goto exit;
 			}
 
-			len -= done;
+			len -= (ssize_t) done;
 			p += done;
 		}
 	}
 
+exit:
 	sptps_stop(&sptps);
 	ecdsa_free(hiskey);
 	ecdsa_free(key);
 	closesocket(sock);
 
 	if(!success) {
-		fprintf(stderr, "Connection closed by peer, invitation cancelled.\n");
+		fprintf(stderr, "Invitation cancelled.\n");
 		return 1;
 	}