X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Finvitation.c;h=22fd6146030b29cbb7d4e90f9bcec24da47535e8;hb=373b0c12d9d0e8a3b449fd18be704e28dd6403e1;hp=5dc8c6300e452819caa3c963b44b843886bcf9a8;hpb=356118324f7cde276f393162fca54040f8c67f04;p=tinc

diff --git a/src/invitation.c b/src/invitation.c
index 5dc8c630..22fd6146 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
@@ -97,7 +97,7 @@ 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 +111,9 @@ char *get_my_hostname() {
 		scan_for_hostname(tinc_conf, &hostname, &port);
 	}
 
+	free(name);
+	name = NULL;
+
 	if(hostname) {
 		goto done;
 	}
@@ -133,7 +136,7 @@ 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 +170,7 @@ 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;
 			}
 
@@ -181,6 +184,7 @@ char *get_my_hostname() {
 	if(!tty) {
 		if(!hostname) {
 			fprintf(stderr, "Could not determine the external address or hostname. Please set Address manually.\n");
+			free(port);
 			return NULL;
 		}
 
@@ -199,6 +203,7 @@ again:
 	if(!fgets(line, sizeof(line), stdin)) {
 		fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
 		free(hostname);
+		free(port);
 		return NULL;
 	}
 
@@ -211,7 +216,7 @@ again:
 	}
 
 	for(char *p = line; *p; p++) {
-		if(isalnum(*p) || *p == '-' || *p == '.') {
+		if(isalnum((uint8_t) *p) || *p == '-' || *p == '.') {
 			continue;
 		}
 
@@ -287,6 +292,7 @@ int cmd_invite(int argc, char *argv[]) {
 		return 1;
 	}
 
+	free(myname);
 	myname = get_my_name(true);
 
 	if(!myname) {
@@ -353,7 +359,11 @@ int cmd_invite(int argc, char *argv[]) {
 
 		char invname[PATH_MAX];
 		struct stat st;
-		snprintf(invname, sizeof(invname), "%s" SLASH "%s", filename, ent->d_name);
+
+		if((size_t)snprintf(invname, sizeof(invname), "%s" SLASH "%s", filename, ent->d_name) >= sizeof(invname)) {
+			fprintf(stderr, "Filename too long: %s" SLASH "%s\n", filename, ent->d_name);
+			continue;
+		}
 
 		if(!stat(invname, &st)) {
 			if(deadline < st.st_mtime) {
@@ -401,6 +411,7 @@ 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;
 		}
 
@@ -409,13 +420,16 @@ 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;
 		}
 
 		fclose(f);
 
-		if(connect_tincd(false)) {
+		if(connect_tincd(true)) {
 			sendline(fd, "%d %d", CONTROL, REQ_RELOAD);
+		} else {
+			fprintf(stderr, "Could not signal the tinc daemon. Please restart or reload it manually.\n");
 		}
 	} else {
 		key = ecdsa_read_pem_private_key(f);
@@ -434,21 +448,27 @@ 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);
+
+	free(fingerprint);
 
-	b64encode_urlsafe(cookie, cookie, 18);
+	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);
@@ -527,15 +547,13 @@ 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;
 	}
@@ -545,16 +563,15 @@ static char *get_line(const char **data) {
 		return NULL;
 	}
 
-	static char line[1024];
 	const char *end = strchr(*data, '\n');
-	size_t len = end ? end - *data : strlen(*data);
+	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();
 	}
 
@@ -571,7 +588,9 @@ 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;
@@ -597,7 +616,7 @@ 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])) {
@@ -627,7 +646,7 @@ static char *grep(const char *data, const char *var) {
 		return xstrdup(p);
 	}
 
-	if(e - p >= sizeof(value)) {
+	if((size_t)(e - p) >= sizeof(value)) {
 		fprintf(stderr, "Maximum line length exceeded!\n");
 		return NULL;
 	}
@@ -638,7 +657,7 @@ static char *grep(const char *data, const char *var) {
 }
 
 static bool finalize_join(void) {
-	char *name = xstrdup(get_value(data, "Name"));
+	const char *name = get_value(data, "Name");
 
 	if(!name) {
 		fprintf(stderr, "No Name found in invitation!\n");
@@ -651,7 +670,7 @@ static bool finalize_join(void) {
 	}
 
 	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");
@@ -686,7 +705,7 @@ 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;
 	}
@@ -751,14 +770,16 @@ 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 ");
 
@@ -823,8 +844,12 @@ make_names:
 			fprintf(stderr, "Ignoring unknown variable '%s' in invitation.\n", l);
 			continue;
 		} else if(!(variables[i].type & VAR_SAFE)) {
-			fprintf(stderr, "Ignoring unsafe variable '%s' in invitation.\n", l);
-			continue;
+			if(force) {
+				fprintf(stderr, "Warning: unsafe variable '%s' in invitation.\n", l);
+			} else {
+				fprintf(stderr, "Ignoring unsafe variable '%s' in invitation.\n", l);
+				continue;
+			}
 		}
 
 		// Copy the safe variable to the right config file
@@ -854,12 +879,12 @@ 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;
@@ -953,7 +978,11 @@ ask_netname:
 		line[strlen(line) - 1] = 0;
 
 		char newbase[PATH_MAX];
-		snprintf(newbase, sizeof(newbase), CONFDIR SLASH "tinc" SLASH "%s", line);
+
+		if((size_t)snprintf(newbase, sizeof(newbase), CONFDIR SLASH "tinc" SLASH "%s", line) >= sizeof(newbase)) {
+			fprintf(stderr, "Filename too long: " CONFDIR SLASH "tinc" SLASH "%s\n", line);
+			goto ask_netname;
+		}
 
 		if(rename(confbase, newbase)) {
 			fprintf(stderr, "Error trying to rename %s to %s: %s\n", confbase, newbase, strerror(errno));
@@ -966,7 +995,12 @@ ask_netname:
 
 	char filename2[PATH_MAX];
 	snprintf(filename, sizeof(filename), "%s" SLASH "tinc-up.invitation", confbase);
+
+#ifdef HAVE_WINDOWS
+	snprintf(filename2, sizeof(filename2), "%s" SLASH "tinc-up.bat", confbase);
+#else
 	snprintf(filename2, sizeof(filename2), "%s" SLASH "tinc-up", confbase);
+#endif
 
 	if(valid_tinc_up) {
 		if(tty) {
@@ -994,8 +1028,18 @@ ask_netname:
 
 				if(response == 'e') {
 					char *command;
-#ifndef HAVE_MINGW
-					xasprintf(&command, "\"%s\" \"%s\"", getenv("VISUAL") ? : getenv("EDITOR") ? : "vi", filename);
+#ifndef HAVE_WINDOWS
+					const char *editor = getenv("VISUAL");
+
+					if(!editor) {
+						editor = getenv("EDITOR");
+					}
+
+					if(!editor) {
+						editor = "vi";
+					}
+
+					xasprintf(&command, "\"%s\" \"%s\"", editor, filename);
 #else
 					xasprintf(&command, "edit \"%s\"", filename);
 #endif
@@ -1018,7 +1062,13 @@ 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.
@@ -1032,11 +1082,15 @@ ask_netname:
 }
 
 
-static bool invitation_send(void *handle, uint8_t type, const void *data, size_t len) {
+static bool invitation_send(void *handle, uint8_t type, const void *vdata, size_t len) {
+	(void)handle;
+	(void)type;
+	const char *data = vdata;
+
 	while(len) {
-		int result = send(sock, data, len, 0);
+		ssize_t result = send(sock, data, len, 0);
 
-		if(result == -1 && errno == EINTR) {
+		if(result == -1 && sockwouldblock(sockerrno)) {
 			continue;
 		} else if(result <= 0) {
 			return false;
@@ -1050,6 +1104,8 @@ static bool invitation_send(void *handle, uint8_t type, const void *data, size_t
 }
 
 static bool invitation_receive(void *handle, uint8_t type, const void *msg, uint16_t len) {
+	(void)handle;
+
 	switch(type) {
 	case SPTPS_HANDSHAKE:
 		return sptps_send_record(&sptps, 0, cookie, sizeof(cookie));
@@ -1065,7 +1121,7 @@ static bool invitation_receive(void *handle, uint8_t type, const void *msg, uint
 		return finalize_join();
 
 	case 2:
-		fprintf(stderr, "Invitation succesfully accepted.\n");
+		fprintf(stderr, "Invitation successfully accepted.\n");
 		shutdown(sock, SHUT_RDWR);
 		success = true;
 		break;
@@ -1169,10 +1225,11 @@ 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;
 	}
 
@@ -1189,6 +1246,8 @@ int cmd_join(int argc, char *argv[]) {
 	struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
 
 	if(!ai) {
+		free(b64key);
+		ecdsa_free(key);
 		return 1;
 	}
 
@@ -1201,6 +1260,9 @@ next:
 		aip = aip->ai_next;
 
 		if(!aip) {
+			freeaddrinfo(ai);
+			free(b64key);
+			ecdsa_free(key);
 			return 1;
 		}
 	}
@@ -1225,9 +1287,9 @@ 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 || len >= sizeof(line)) {
+	if(len <= 0 || (size_t)len >= sizeof(line)) {
 		abort();
 	}
 
@@ -1246,17 +1308,26 @@ next:
 		goto 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;
 	char hishash[64];
 
 	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;
 
 	}
@@ -1264,50 +1335,67 @@ 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))) {
 		if(len < 0) {
-			if(errno == EINTR) {
+			if(sockwouldblock(sockerrno)) {
 				continue;
 			}
 
-			fprintf(stderr, "Error reading data from %s port %s: %s\n", address, port, strerror(errno));
-			return 1;
+#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
+			// have to do an explicit check here.
+			if(sockshutdown(sockerrno)) {
+				break;
+			}
+
+#endif
+			fprintf(stderr, "Error reading data from %s port %s: %s\n", address, port, sockstrerror(sockerrno));
+			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;
 	}