/*
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
fclose(f);
}
-char *get_my_hostname() {
+static char *get_my_hostname(void) {
char *hostname = NULL;
char *port = NULL;
char *hostport = NULL;
scan_for_hostname(tinc_conf, &hostname, &port);
}
+ free(name);
+ name = NULL;
+
if(hostname) {
goto done;
}
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;
// 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;
}
if(!tty) {
if(!hostname) {
fprintf(stderr, "Could not determine the external address or hostname. Please set Address manually.\n");
+ free(port);
return NULL;
}
if(!fgets(line, sizeof(line), stdin)) {
fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
free(hostname);
+ free(port);
return NULL;
}
}
for(char *p = line; *p; p++) {
- if(isalnum(*p) || *p == '-' || *p == '.') {
+ if(isalnum((uint8_t) *p) || *p == '-' || *p == '.') {
continue;
}
return 1;
}
+ free(myname);
myname = get_my_name(true);
if(!myname) {
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) {
if(!f) {
fprintf(stderr, "Could not write %s: %s\n", filename, strerror(errno));
+ ecdsa_free(key);
return 1;
}
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);
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);
}
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;
}
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();
}
}
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;
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])) {
return xstrdup(p);
}
- if(e - p >= sizeof(value)) {
+ if((size_t)(e - p) >= sizeof(value)) {
fprintf(stderr, "Maximum line length exceeded!\n");
return NULL;
}
}
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");
}
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");
// 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;
}
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 ");
l[len] = 0;
+ // Ignore lines with empty variable names
+ if(!*l) {
+ continue;
+ }
+
// Is it a Name?
- if(!strcasecmp(l, "Name"))
+ if(!strcasecmp(l, "Name")) {
if(strcmp(value, name)) {
break;
} else {
continue;
- } else if(!strcasecmp(l, "NetName")) {
+ }
+ } else if(!strcasecmp(l, "NetName")) {
continue;
}
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
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;
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));
char filename2[PATH_MAX];
snprintf(filename, sizeof(filename), "%s" SLASH "tinc-up.invitation", confbase);
+
+#ifdef HAVE_MINGW
+ 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) {
if(response == 'e') {
char *command;
#ifndef HAVE_MINGW
- xasprintf(&command, "\"%s\" \"%s\"", getenv("VISUAL") ? : getenv("EDITOR") ? : "vi", filename);
+ 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
}
}
} 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.
}
-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;
}
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));
return finalize_join();
case 2:
- fprintf(stderr, "Invitation succesfully accepted.\n");
+ fprintf(stderr, "Invitation successfully accepted.\n");
shutdown(sock, SHUT_RDWR);
success = true;
break;
}
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;
}
struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
if(!ai) {
+ free(b64key);
+ ecdsa_free(key);
return 1;
}
aip = aip->ai_next;
if(!aip) {
+ freeaddrinfo(ai);
+ free(b64key);
+ ecdsa_free(key);
return 1;
}
}
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();
}
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;
}
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_MINGW
+
+ // 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;
}