-/*
- invitation.c -- Create and accept invitations
- Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
-
- 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
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License along
- with this program; if not, write to the Free Software Foundation, Inc.,
- 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-*/
-
-#include "system.h"
-
-#include "control_common.h"
-#include "crypto.h"
-#include "ecdsa.h"
-#include "ecdsagen.h"
-#include "invitation.h"
-#include "netutl.h"
-#include "sptps.h"
-#include "tincctl.h"
-#include "utils.h"
-#include "xalloc.h"
-
-int addressfamily = AF_UNSPEC;
-
-static void scan_for_hostname(const char *filename, char **hostname, char **port) {
- if(!filename || (*hostname && *port))
- return;
-
- FILE *f = fopen(filename, "r");
- if(!f)
- return;
-
- while(fgets(line, sizeof line, f)) {
- if(!rstrip(line))
- continue;
- char *p = line, *q;
- p += strcspn(p, "\t =");
- if(!*p)
- continue;
- q = p + strspn(p, "\t ");
- if(*q == '=')
- q += 1 + strspn(q + 1, "\t ");
- *p = 0;
- p = q + strcspn(q, "\t ");
- if(*p)
- *p++ = 0;
- p += strspn(p, "\t ");
- p[strcspn(p, "\t ")] = 0;
-
- if(!*port && !strcasecmp(line, "Port")) {
- *port = xstrdup(q);
- } else if(!*hostname && !strcasecmp(line, "Address")) {
- *hostname = xstrdup(q);
- if(*p) {
- free(*port);
- *port = xstrdup(p);
- }
- }
-
- if(*hostname && *port)
- break;
- }
-
- fclose(f);
-}
-
-char *get_my_hostname() {
- char *hostname = NULL;
- char *port = NULL;
- char *hostport = NULL;
- char *name = get_my_name(false);
- char filename[PATH_MAX];
-
- // Use first Address statement in own host config file
- if(check_id(name)) {
- snprintf(filename,PATH_MAX, "%s" SLASH "hosts" SLASH "%s", confbase, name);
- scan_for_hostname(filename, &hostname, &port);
- scan_for_hostname(tinc_conf, &hostname, &port);
- }
-
- if(hostname)
- goto done;
-
- // If that doesn't work, guess externally visible hostname
- fprintf(stderr, "Trying to discover externally visible hostname...\n");
- struct addrinfo *ai = str2addrinfo("tinc-vpn.org", "80", SOCK_STREAM);
- struct addrinfo *aip = ai;
- static const char request[] = "GET http://tinc-vpn.org/host.cgi HTTP/1.0\r\n\r\n";
-
- while(aip) {
- int s = socket(aip->ai_family, aip->ai_socktype, aip->ai_protocol);
- if(s >= 0) {
- if(connect(s, aip->ai_addr, aip->ai_addrlen)) {
- closesocket(s);
- s = -1;
- }
- }
- if(s >= 0) {
- send(s, request, sizeof request - 1, 0);
- int len = recv(s, line, sizeof line - 1, MSG_WAITALL);
- if(len > 0) {
- line[len] = 0;
- if(line[len - 1] == '\n')
- line[--len] = 0;
- char *p = strrchr(line, '\n');
- if(p && p[1])
- hostname = xstrdup(p + 1);
- }
- closesocket(s);
- if(hostname)
- break;
- }
- aip = aip->ai_next;
- continue;
- }
-
- if(ai)
- freeaddrinfo(ai);
-
- // Check that the hostname is reasonable
- if(hostname) {
- for(char *p = hostname; *p; p++) {
- if(isalnum(*p) || *p == '-' || *p == '.' || *p == ':')
- continue;
- // If not, forget it.
- free(hostname);
- hostname = NULL;
- break;
- }
- }
-
- if(!tty) {
- if(!hostname) {
- fprintf(stderr, "Could not determine the external address or hostname. Please set Address manually.\n");
- return NULL;
- }
- goto save;
- }
-
-again:
- fprintf(stderr, "Please enter your host's external address or hostname");
- if(hostname)
- fprintf(stderr, " [%s]", hostname);
- fprintf(stderr, ": ");
-
- if(!fgets(line, sizeof line, stdin)) {
- fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
- free(hostname);
- return NULL;
- }
-
- if(!rstrip(line)) {
- if(hostname)
- goto save;
- else
- goto again;
- }
-
- for(char *p = line; *p; p++) {
- if(isalnum(*p) || *p == '-' || *p == '.')
- continue;
- fprintf(stderr, "Invalid address or hostname.\n");
- goto again;
- }
-
- free(hostname);
- hostname = xstrdup(line);
-
-save:
- if(filename) {
- FILE *f = fopen(filename, "a");
- if(f) {
- fprintf(f, "\nAddress = %s\n", hostname);
- fclose(f);
- } else {
- fprintf(stderr, "Could not append Address to %s: %s\n", filename, strerror(errno));
- }
- }
-
-done:
- if(port) {
- if(strchr(hostname, ':'))
- xasprintf(&hostport, "[%s]:%s", hostname, port);
- else
- xasprintf(&hostport, "%s:%s", hostname, port);
- } else {
- if(strchr(hostname, ':'))
- xasprintf(&hostport, "[%s]", hostname);
- else
- hostport = xstrdup(hostname);
- }
-
- free(hostname);
- free(port);
- return hostport;
-}
-
-static bool fcopy(FILE *out, const char *filename) {
- FILE *in = fopen(filename, "r");
- if(!in) {
- fprintf(stderr, "Could not open %s: %s\n", filename, strerror(errno));
- return false;
- }
-
- char buf[1024];
- size_t len;
- while((len = fread(buf, 1, sizeof buf, in)))
- fwrite(buf, len, 1, out);
- fclose(in);
- return true;
-}
-
-int cmd_invite(int argc, char *argv[]) {
- if(argc < 2) {
- fprintf(stderr, "Not enough arguments!\n");
- return 1;
- }
-
- // Check validity of the new node's name
- if(!check_id(argv[1])) {
- fprintf(stderr, "Invalid name for node.\n");
- return 1;
- }
-
- char *myname = get_my_name(true);
- if(!myname)
- return 1;
-
- // Ensure no host configuration file with that name exists
- char filename [PATH_MAX];
- snprintf(filename,PATH_MAX, "%s" SLASH "hosts" SLASH "%s", confbase, argv[1]);
- if(!access(filename, F_OK)) {
- fprintf(stderr, "A host config file for %s already exists!\n", argv[1]);
- return 1;
- }
-
- // If a daemon is running, ensure no other nodes now about this name
- bool found = false;
- if(connect_tincd(false)) {
- sendline(fd, "%d %d", CONTROL, REQ_DUMP_NODES);
-
- while(recvline(fd, line, sizeof line)) {
- char node[4096];
- int code, req;
- if(sscanf(line, "%d %d %s", &code, &req, node) != 3)
- break;
- if(!strcmp(node, argv[1]))
- found = true;
- }
-
- if(found) {
- fprintf(stderr, "A node with name %s is already known!\n", argv[1]);
- return 1;
- }
- }
-
- char hash[64];
-
- snprintf(filename,PATH_MAX, "%s" SLASH "invitations", confbase);
- if(mkdir(filename, 0700) && errno != EEXIST) {
- fprintf(stderr, "Could not create directory %s: %s\n", filename, strerror(errno));
- return 1;
- }
-
- // Count the number of valid invitations, clean up old ones
- DIR *dir = opendir(filename);
- if(!dir) {
- fprintf(stderr, "Could not read directory %s: %s\n", filename, strerror(errno));
- return 1;
- }
-
- errno = 0;
- int count = 0;
- struct dirent *ent;
- time_t deadline = time(NULL) - 604800; // 1 week in the past
-
- while((ent = readdir(dir))) {
- if(strlen(ent->d_name) != 24)
- continue;
- char invname[PATH_MAX];
- struct stat st;
- snprintf(invname,PATH_MAX, "%s" SLASH "%s", filename, ent->d_name);
- if(!stat(invname, &st)) {
- if(deadline < st.st_mtime)
- count++;
- else
- unlink(invname);
- } else {
- fprintf(stderr, "Could not stat %s: %s\n", invname, strerror(errno));
- errno = 0;
- }
- }
-
- if(errno) {
- fprintf(stderr, "Error while reading directory %s: %s\n", filename, strerror(errno));
- closedir(dir);
- return 1;
- }
-
- closedir(dir);
-
- ecdsa_t *key;
- snprintf(filename,PATH_MAX, "%s" SLASH "invitations" SLASH "ecdsa_key.priv", confbase);
-
- // Remove the key if there are no outstanding invitations.
- if(!count)
- unlink(filename);
-
- // Create a new key if necessary.
- FILE *f = fopen(filename, "r");
- if(!f) {
- if(errno != ENOENT) {
- fprintf(stderr, "Could not read %s: %s\n", filename, strerror(errno));
- return 1;
- }
-
- key = ecdsa_generate();
- if(!key) {
- return 1;
- }
- f = fopen(filename, "w");
- if(!f) {
- fprintf(stderr, "Could not write %s: %s\n", filename, strerror(errno));
- return 1;
- }
- chmod(filename, 0600);
- ecdsa_write_pem_private_key(key, f);
- fclose(f);
-
- if(connect_tincd(false))
- sendline(fd, "%d %d", CONTROL, REQ_RELOAD);
- } else {
- key = ecdsa_read_pem_private_key(f);
- fclose(f);
- if(!key)
- fprintf(stderr, "Could not read private key from %s\n", filename);
- }
-
- if(!key)
- return 1;
-
- // Create a hash of the key.
- char *fingerprint = ecdsa_get_base64_public_key(key);
- sha512(fingerprint, strlen(fingerprint), hash);
- b64encode_urlsafe(hash, hash, 18);
-
- // 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)];
- char cookiehash[64];
- memcpy(buf, cookie, 18);
- memcpy(buf + 18, fingerprint, sizeof buf - 18);
- sha512(buf, sizeof buf, cookiehash);
- b64encode_urlsafe(cookiehash, cookiehash, 18);
-
- b64encode_urlsafe(cookie, cookie, 18);
-
- // Create a file containing the details of the invitation.
- snprintf(filename,PATH_MAX, "%s" SLASH "invitations" SLASH "%s", confbase, cookiehash);
- int ifd = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
- if(!ifd) {
- fprintf(stderr, "Could not create invitation file %s: %s\n", filename, strerror(errno));
- return 1;
- }
- f = fdopen(ifd, "w");
- if(!f)
- abort();
-
- // Get the local address
- char *address = get_my_hostname();
-
- // Fill in the details.
- fprintf(f, "Name = %s\n", argv[1]);
- if(netname)
- fprintf(f, "NetName = %s\n", netname);
- fprintf(f, "ConnectTo = %s\n", myname);
-
- // Copy Broadcast and Mode
- FILE *tc = fopen(tinc_conf, "r");
- if(tc) {
- char buf[1024];
- while(fgets(buf, sizeof buf, tc)) {
- if((!strncasecmp(buf, "Mode", 4) && strchr(" \t=", buf[4]))
- || (!strncasecmp(buf, "Broadcast", 9) && strchr(" \t=", buf[9]))) {
- fputs(buf, f);
- // Make sure there is a newline character.
- if(!strchr(buf, '\n'))
- fputc('\n', f);
- }
- }
- fclose(tc);
- }
-
- fprintf(f, "#---------------------------------------------------------------#\n");
- fprintf(f, "Name = %s\n", myname);
-
- char filename2[PATH_MAX];
- snsprintf(filename2,PATH_MAX, "%s" SLASH "hosts" SLASH "%s", confbase, myname);
- fcopy(f, filename2);
- fclose(f);
-
- // Create an URL from the local address, key hash and cookie
- char *url;
- xasprintf(&url, "%s/%s%s", address, hash, cookie);
-
- return 0;
-}
-
-static int sock;
-static char cookie[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) {
- if(!data || !*data)
- return NULL;
-
- if(!**data) {
- *data = NULL;
- return NULL;
- }
-
- static char line[1024];
- const char *end = strchr(*data, '\n');
- size_t len = end ? end - *data : strlen(*data);
- if(len >= sizeof line) {
- fprintf(stderr, "Maximum line length exceeded!\n");
- return NULL;
- }
- if(len && !isprint(**data))
- abort();
-
- memcpy(line, *data, len);
- line[len] = 0;
-
- if(end)
- *data = end + 1;
- else
- *data = NULL;
-
- return line;
-}
-
-static char *get_value(const char *data, const char *var) {
- char *line = get_line(&data);
- if(!line)
- return NULL;
-
- char *sep = line + strcspn(line, " \t=");
- char *val = sep + strspn(sep, " \t");
- if(*val == '=')
- val += 1 + strspn(val + 1, " \t");
- *sep = 0;
- if(strcasecmp(line, var))
- return NULL;
- return val;
-}
-
-static char *grep(const char *data, const char *var) {
- static char value[1024];
-
- const char *p = data;
- int varlen = strlen(var);
-
- // Skip all lines not starting with var
- while(strncasecmp(p, var, varlen) || !strchr(" \t=", p[varlen])) {
- p = strchr(p, '\n');
- if(!p)
- break;
- else
- p++;
- }
-
- if(!p)
- return NULL;
-
- p += varlen;
- p += strspn(p, " \t");
- if(*p == '=')
- p += 1 + strspn(p + 1, " \t");
-
- const char *e = strchr(p, '\n');
- if(!e)
- return xstrdup(p);
-
- if(e - p >= sizeof value) {
- fprintf(stderr, "Maximum line length exceeded!\n");
- return NULL;
- }
-
- memcpy(value, p, e - p);
- value[e - p] = 0;
- return value;
-}
-
-static bool finalize_join(void) {
- char *name = xstrdup(get_value(data, "Name"));
- if(!name) {
- fprintf(stderr, "No Name found in invitation!\n");
- return false;
- }
-
- if(!check_id(name)) {
- fprintf(stderr, "Invalid Name found in invitation: %s!\n", name);
- return false;
- }
-
- if(!netname)
- netname = grep(data, "NetName");
-
- bool ask_netname = false;
- char temp_netname[32];
-
-make_names:
- free(tinc_conf);
- free(hosts_dir);
-
- xasprintf(&tinc_conf, "%s" SLASH "tinc.conf", confbase);
- xasprintf(&hosts_dir, "%s" SLASH "hosts", confbase);
-
- if(!access(tinc_conf, F_OK)) {
- fprintf(stderr, "Configuration file %s already exists!\n", tinc_conf);
- if(confbasegiven)
- return false;
-
- // Generate a random netname, ask for a better one later.
- ask_netname = true;
- snprintf(temp_netname, sizeof temp_netname, "join_%x", rand());
- netname = temp_netname;
- goto make_names;
- }
-
- if(mkdir(confbase, 0777) && errno != EEXIST) {
- fprintf(stderr, "Could not create directory %s: %s\n", confbase, strerror(errno));
- return false;
- }
-
- if(mkdir(hosts_dir, 0777) && errno != EEXIST) {
- fprintf(stderr, "Could not create directory %s: %s\n", hosts_dir, strerror(errno));
- return false;
- }
-
- FILE *f = fopen(tinc_conf, "w");
- if(!f) {
- fprintf(stderr, "Could not create file %s: %s\n", tinc_conf, strerror(errno));
- return false;
- }
-
- fprintf(f, "Name = %s\n", name);
-
- char filename[PATH_MAX];
- snprintf(filename,PATH_MAX, "%s" SLASH "%s", hosts_dir, name);
- FILE *fh = fopen(filename, "w");
- if(!fh) {
- fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
- return false;
- }
-
- // Filter first chunk on approved keywords, split between tinc.conf and hosts/Name
- // Other chunks go unfiltered to their respective host config files
- const char *p = data;
- char *l, *value;
-
- while((l = get_line(&p))) {
- // Ignore comments
- if(*l == '#')
- continue;
-
- // Split line into variable and value
- int len = strcspn(l, "\t =");
- value = l + len;
- value += strspn(value, "\t ");
- if(*value == '=') {
- value++;
- value += strspn(value, "\t ");
- }
- l[len] = 0;
-
- // Is it a Name?
- if(!strcasecmp(l, "Name"))
- if(strcmp(value, name))
- break;
- else
- continue;
- else if(!strcasecmp(l, "NetName"))
- continue;
-
- // Check the list of known variables
- bool found = false;
- int i;
- for(i = 0; variables[i].name; i++) {
- if(strcasecmp(l, variables[i].name))
- continue;
- found = true;
- break;
- }
-
- // Ignore unknown and unsafe variables
- if(!found) {
- 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;
- }
-
- // Copy the safe variable to the right config file
- fprintf(variables[i].type & VAR_HOST ? fh : f, "%s = %s\n", l, value);
- }
-
- fclose(f);
-
- while(l && !strcasecmp(l, "Name")) {
- if(!check_id(value)) {
- fprintf(stderr, "Invalid Name found in invitation.\n");
- return false;
- }
-
- if(!strcmp(value, name)) {
- fprintf(stderr, "Secondary chunk would overwrite our own host config file.\n");
- return false;
- }
-
- snprintf(filename,PATH_MAX, "%s" SLASH "%s", hosts_dir, value);
- f = fopen(filename, "w");
-
- if(!f) {
- fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
- return false;
- }
-
- while((l = get_line(&p))) {
- if(!strcmp(l, "#---------------------------------------------------------------#"))
- continue;
- int len = strcspn(l, "\t =");
- if(len == 4 && !strncasecmp(l, "Name", 4)) {
- value = l + len;
- value += strspn(value, "\t ");
- if(*value == '=') {
- value++;
- value += strspn(value, "\t ");
- }
- l[len] = 0;
- break;
- }
-
- fputs(l, f);
- fputc('\n', f);
- }
-
- fclose(f);
- }
-
- // Generate our key and send a copy to the server
- ecdsa_t *key = ecdsa_generate();
- if(!key)
- return false;
-
- char *b64key = ecdsa_get_base64_public_key(key);
- if(!b64key)
- return false;
-
- snprintf(filename,PATH_MAX, "%s" SLASH "ecdsa_key.priv", confbase);
- f = fopenmask(filename, "w", 0600);
-
- if(!ecdsa_write_pem_private_key(key, f)) {
- fprintf(stderr, "Error writing private key!\n");
- ecdsa_free(key);
- fclose(f);
- return false;
- }
-
- fclose(f);
-
- fprintf(fh, "ECDSAPublicKey = %s\n", b64key);
-
- sptps_send_record(&sptps, 1, b64key, strlen(b64key));
- free(b64key);
-
- ecdsa_free(key);
-
- check_port(name);
-
-ask_netname:
- if(ask_netname && tty) {
- fprintf(stderr, "Enter a new netname: ");
- if(!fgets(line, sizeof line, stdin)) {
- fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
- return false;
- }
- if(!*line || *line == '\n')
- goto ask_netname;
-
- line[strlen(line) - 1] = 0;
-
- char *newbase;
- xasprintf(&newbase, CONFDIR SLASH "tinc" SLASH "%s", line);
- if(rename(confbase, newbase)) {
- fprintf(stderr, "Error trying to rename %s to %s: %s\n", confbase, newbase, strerror(errno));
- free(newbase);
- goto ask_netname;
- }
-
- free(newbase);
- netname = line;
- }
-
- fprintf(stderr, "Configuration stored in: %s\n", confbase);
-
- return true;
-}
-
-
-static bool invitation_send(void *handle, uint8_t type, const char *data, size_t len) {
- while(len) {
- int result = send(sock, data, len, 0);
- if(result == -1 && errno == EINTR)
- continue;
- else if(result <= 0)
- return false;
- data += result;
- len -= result;
- }
- return true;
-}
-
-static bool invitation_receive(void *handle, uint8_t type, const char *msg, uint16_t len) {
- switch(type) {
- case SPTPS_HANDSHAKE:
- return sptps_send_record(&sptps, 0, cookie, sizeof cookie);
-
- case 0:
- data = xrealloc(data, datalen + len + 1);
- memcpy(data + datalen, msg, len);
- datalen += len;
- data[datalen] = 0;
- break;
-
- case 1:
- return finalize_join();
-
- case 2:
- fprintf(stderr, "Invitation succesfully accepted.\n");
- shutdown(sock, SHUT_RDWR);
- success = true;
- break;
-
- default:
- return false;
- }
-
- return true;
-}
-
-int cmd_join(int argc, char *argv[]) {
- free(data);
- data = NULL;
- datalen = 0;
-
- if(argc > 2) {
- fprintf(stderr, "Too many arguments!\n");
- return 1;
- }
-
- // Make sure confbase exists and is accessible.
- if(mkdir(confbase, 0777) && errno != EEXIST) {
- fprintf(stderr, "Could not create directory %s: %s\n", confbase, strerror(errno));
- return 1;
- }
-
- if(access(confbase, R_OK | W_OK | X_OK)) {
- fprintf(stderr, "No permission to write in directory %s: %s\n", confbase, strerror(errno));
- return 1;
- }
-
- // If a netname or explicit configuration directory is specified, check for an existing tinc.conf.
- if((netname || confbasegiven) && !access(tinc_conf, F_OK)) {
- fprintf(stderr, "Configuration file %s already exists!\n", tinc_conf);
- return 1;
- }
-
- // Either read the invitation from the command line or from stdin.
- char *invitation;
-
- if(argc > 1) {
- invitation = argv[1];
- } else {
- if(tty)
- fprintf(stderr, "Enter invitation URL: ");
- errno = EPIPE;
- if(!fgets(line, sizeof line, stdin)) {
- fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
- return false;
- }
- invitation = line;
- }
-
- // Parse the invitation URL.
- rstrip(line);
-
- char *slash = strchr(invitation, '/');
- if(!slash)
- goto invalid;
-
- *slash++ = 0;
-
- if(strlen(slash) != 48)
- goto invalid;
-
- char *address = invitation;
- char *port = NULL;
- if(*address == '[') {
- address++;
- char *bracket = strchr(address, ']');
- if(!bracket)
- goto invalid;
- *bracket = 0;
- if(bracket[1] == ':')
- port = bracket + 2;
- } else {
- port = strchr(address, ':');
- if(port)
- *port++ = 0;
- }
-
- if(!port || !*port)
- port = "655";
-
- if(!b64decode(slash, hash, 18) || !b64decode(slash + 24, cookie, 18))
- goto invalid;
-
- // Generate a throw-away key for the invitation.
- ecdsa_t *key = ecdsa_generate();
- if(!key)
- return 1;
-
- char *b64key = ecdsa_get_base64_public_key(key);
-
- // Connect to the tinc daemon mentioned in the URL.
- struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
- if(!ai)
- return 1;
-
- sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
- if(sock <= 0) {
- fprintf(stderr, "Could not open socket: %s\n", strerror(errno));
- return 1;
- }
-
- if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
- fprintf(stderr, "Could not connect to %s port %s: %s\n", address, port, strerror(errno));
- closesocket(sock);
- 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);
- if(len <= 0 || len >= sizeof line)
- abort();
-
- if(!sendline(sock, "0 ?%s %d.%d", b64key, PROT_MAJOR, 1)) {
- fprintf(stderr, "Error sending request to %s port %s: %s\n", address, port, strerror(errno));
- closesocket(sock);
- return 1;
- }
-
- char hisname[4096] = "";
- int code, hismajor, hisminor = 0;
-
- if(!recvline(sock, line, sizeof line) || sscanf(line, "%d %s %d.%d", &code, hisname, &hismajor, &hisminor) < 3 || code != 0 || hismajor != PROT_MAJOR || !check_id(hisname) || !recvline(sock, line, sizeof line) || !rstrip(line) || sscanf(line, "%d ", &code) != 1 || code != ACK || strlen(line) < 3) {
- fprintf(stderr, "Cannot read greeting from peer\n");
- closesocket(sock);
- return 1;
- }
-
- // 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 hash\n%s\n", line + 2);
- return 1;
- }
- if(memcmp(hishash, hash, 18)) {
- fprintf(stderr, "Peer has an invalid key!\n%s\n", line + 2);
- return 1;
-
- }
-
- ecdsa_t *hiskey = ecdsa_set_base64_public_key(fingerprint);
- if(!hiskey)
- return 1;
-
- // Start an SPTPS session
- if(!sptps_start(&sptps, NULL, true, false, key, hiskey, "tinc invitation", 15, invitation_send, invitation_receive))
- return 1;
-
- // Feed rest of input buffer to SPTPS
- if(!sptps_receive_data(&sptps, buffer, blen))
- return 1;
-
- while((len = recv(sock, line, sizeof line, 0))) {
- if(len < 0) {
- if(errno == EINTR)
- continue;
- fprintf(stderr, "Error reading data from %s port %s: %s\n", address, port, strerror(errno));
- return 1;
- }
-
- if(!sptps_receive_data(&sptps, line, len))
- return 1;
- }
-
- sptps_stop(&sptps);
- ecdsa_free(hiskey);
- ecdsa_free(key);
- closesocket(sock);
-
- if(!success) {
- fprintf(stderr, "Connection closed by peer, invitation cancelled.\n");
- return 1;
- }
-
- return 0;
-
-invalid:
- fprintf(stderr, "Invalid invitation URL.\n");
- return 1;
-}