Generate a tinc-up script from an invitation.
[tinc] / src / invitation.c
index 6ed17ca..07594ff 100644 (file)
@@ -1,6 +1,6 @@
 /*
     invitation.c -- Create and accept invitations
-    Copyright (C) 2013 Guus Sliepen <guus@tinc-vpn.org>
+    Copyright (C) 2013-2015 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
 #include "crypto.h"
 #include "ecdsa.h"
 #include "ecdsagen.h"
+#include "ifconfig.h"
 #include "invitation.h"
 #include "names.h"
 #include "netutl.h"
 #include "rsagen.h"
+#include "script.h"
 #include "sptps.h"
+#include "subnet.h"
 #include "tincctl.h"
 #include "utils.h"
 #include "xalloc.h"
 
+#include "ed25519/sha512.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 = NULL;
+       char filename[PATH_MAX] = {0};
 
        // Use first Address statement in own host config file
        if(check_id(name)) {
-               xasprintf(&filename, "%s" SLASH "hosts" SLASH "%s", confbase, name);
-               FILE *f = fopen(filename, "r");
-               if(f) {
-                       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);
-                                       continue;
-                               }
-                               if(strcasecmp(line, "Address"))
-                                       continue;
-                               hostname = xstrdup(q);
-                               if(*p) {
-                                       free(port);
-                                       port = xstrdup(p);
-                               }
-                               break;
-                       }
-                       fclose(f);
-               }
+               snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", confbase, name);
+               scan_for_hostname(filename, &hostname, &port);
+               scan_for_hostname(tinc_conf, &hostname, &port);
        }
 
        if(hostname)
@@ -130,12 +146,19 @@ char *get_my_hostname() {
                }
        }
 
+       if(!tty) {
+               if(!hostname) {
+                       fprintf(stderr, "Could not determine the external address or hostname. Please set Address manually.\n");
+                       return NULL;
+               }
+               goto save;
+       }
+
 again:
-       printf("Please enter your host's external address or hostname");
+       fprintf(stderr, "Please enter your host's external address or hostname");
        if(hostname)
-               printf(" [%s]", hostname);
-       printf(": ");
-       fflush(stdout);
+               fprintf(stderr, " [%s]", hostname);
+       fprintf(stderr, ": ");
 
        if(!fgets(line, sizeof line, stdin)) {
                fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
@@ -161,7 +184,7 @@ again:
        hostname = xstrdup(line);
 
 save:
-       if(filename) {
+       if(*filename) {
                FILE *f = fopen(filename, "a");
                if(f) {
                        fprintf(f, "\nAddress = %s\n", hostname);
@@ -178,13 +201,14 @@ done:
                else
                        xasprintf(&hostport, "%s:%s", hostname, port);
        } else {
-               hostport = hostname;
-               hostname = NULL;
+               if(strchr(hostname, ':'))
+                       xasprintf(&hostport, "[%s]", hostname);
+               else
+                       hostport = xstrdup(hostname);
        }
 
        free(hostname);
        free(port);
-       free(filename);
        return hostport;
 }
 
@@ -220,16 +244,14 @@ int cmd_invite(int argc, char *argv[]) {
                return 1;
 
        // Ensure no host configuration file with that name exists
-       char *filename = NULL;
-       xasprintf(&filename, "%s" SLASH "hosts" SLASH "%s", confbase, argv[1]);
+       char filename[PATH_MAX];
+       snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", confbase, argv[1]);
        if(!access(filename, F_OK)) {
-               free(filename);
                fprintf(stderr, "A host config file for %s already exists!\n", argv[1]);
                return 1;
        }
-       free(filename);
 
-       // If a daemon is running, ensure no other nodes now about this name
+       // If a daemon is running, ensure no other nodes know about this name
        bool found = false;
        if(connect_tincd(false)) {
                sendline(fd, "%d %d", CONTROL, REQ_DUMP_NODES);
@@ -249,12 +271,9 @@ int cmd_invite(int argc, char *argv[]) {
                }
        }
 
-       char hash[25];
-
-       xasprintf(&filename, "%s" SLASH "invitations", confbase);
+       snprintf(filename, sizeof filename, "%s" SLASH "invitations", confbase);
        if(mkdir(filename, 0700) && errno != EEXIST) {
                fprintf(stderr, "Could not create directory %s: %s\n", filename, strerror(errno));
-               free(filename);
                return 1;
        }
 
@@ -262,7 +281,6 @@ int cmd_invite(int argc, char *argv[]) {
        DIR *dir = opendir(filename);
        if(!dir) {
                fprintf(stderr, "Could not read directory %s: %s\n", filename, strerror(errno));
-               free(filename);
                return 1;
        }
 
@@ -274,9 +292,9 @@ int cmd_invite(int argc, char *argv[]) {
        while((ent = readdir(dir))) {
                if(strlen(ent->d_name) != 24)
                        continue;
-               char *invname;
+               char invname[PATH_MAX];
                struct stat st;
-               xasprintf(&invname, "%s" SLASH "%s", filename, ent->d_name);
+               snprintf(invname, sizeof invname, "%s" SLASH "%s", filename, ent->d_name);
                if(!stat(invname, &st)) {
                        if(deadline < st.st_mtime)
                                count++;
@@ -286,21 +304,17 @@ int cmd_invite(int argc, char *argv[]) {
                        fprintf(stderr, "Could not stat %s: %s\n", invname, strerror(errno));
                        errno = 0;
                }
-               free(invname);
        }
 
+       closedir(dir);
+
        if(errno) {
                fprintf(stderr, "Error while reading directory %s: %s\n", filename, strerror(errno));
-               closedir(dir);
-               free(filename);
                return 1;
        }
                
-       closedir(dir);
-       free(filename);
-
        ecdsa_t *key;
-       xasprintf(&filename, "%s" SLASH "invitations" SLASH "ecdsa_key.priv", confbase);
+       snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "ed25519_key.priv", confbase);
 
        // Remove the key if there are no outstanding invitations.
        if(!count)
@@ -311,55 +325,64 @@ int cmd_invite(int argc, char *argv[]) {
        if(!f) {
                if(errno != ENOENT) {
                        fprintf(stderr, "Could not read %s: %s\n", filename, strerror(errno));
-                       free(filename);
                        return 1;
                }
 
                key = ecdsa_generate();
-               if(!key) {
-                       free(filename);
+               if(!key)
                        return 1;
-               }
                f = fopen(filename, "w");
                if(!f) {
                        fprintf(stderr, "Could not write %s: %s\n", filename, strerror(errno));
-                       free(filename);
                        return 1;
                }
                chmod(filename, 0600);
-               ecdsa_write_pem_private_key(key, f);
+               if(!ecdsa_write_pem_private_key(key, f)) {
+                       fprintf(stderr, "Could not write ECDSA private key\n");
+                       fclose(f);
+                       return 1;
+               }
+               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);
        }
-       fclose(f);
-       free(filename);
+
        if(!key)
                return 1;
 
        // Create a hash of the key.
+       char hash[64];
        char *fingerprint = ecdsa_get_base64_public_key(key);
-       digest_t *digest = digest_open_by_name("sha256", 18);
-       if(!digest)
-               abort();
-       digest_create(digest, fingerprint, strlen(fingerprint), hash);
+       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.
-       xasprintf(&filename, "%s" SLASH "invitations" SLASH "%s", confbase, cookie);
+       snprintf(filename, sizeof filename, "%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));
-               free(filename);
                return 1;
        }
-       free(filename);
        f = fdopen(ifd, "w");
        if(!f)
                abort();
@@ -372,17 +395,48 @@ int cmd_invite(int argc, char *argv[]) {
        if(netname)
                fprintf(f, "NetName = %s\n", netname);
        fprintf(f, "ConnectTo = %s\n", myname);
-       // TODO: copy Broadcast and Mode
+
+       // 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);
 
-       xasprintf(&filename, "%s" SLASH "hosts" SLASH "%s", confbase, myname);
-       fcopy(f, filename);
+       char filename2[PATH_MAX];
+       snprintf(filename2, sizeof filename2, "%s" SLASH "hosts" SLASH "%s", confbase, myname);
+       fcopy(f, filename2);
        fclose(f);
 
        // Create an URL from the local address, key hash and cookie
-       printf("%s/%s%s\n", address, hash, cookie);
-       free(filename);
+       char *url;
+       xasprintf(&url, "%s/%s%s", address, hash, cookie);
+
+       // Call the inviation-created script
+       char *envp[6] = {};
+       xasprintf(&envp[0], "NAME=%s", myname);
+       xasprintf(&envp[1], "NETNAME=%s", netname);
+       xasprintf(&envp[2], "NODE=%s", argv[1]);
+       xasprintf(&envp[3], "INVITATION_FILE=%s", filename);
+       xasprintf(&envp[4], "INVITATION_URL=%s", url);
+       execute_script("invitation-created", envp);
+       for(int i = 0; i < 6 && envp[i]; i++)
+               free(envp[i]);
+
+       puts(url);
+       free(url);
        free(address);
 
        return 0;
@@ -503,7 +557,7 @@ make_names:
                confbase = NULL;
        }
 
-       make_names();
+       make_names(false);
 
        free(tinc_conf);
        free(hosts_dir);
@@ -513,7 +567,7 @@ make_names:
 
        if(!access(tinc_conf, F_OK)) {
                fprintf(stderr, "Configuration file %s already exists!\n", tinc_conf);
-               if(!tty || confbasegiven)
+               if(confbasegiven)
                        return false;
 
                // Generate a random netname, ask for a better one later.
@@ -541,15 +595,29 @@ make_names:
 
        fprintf(f, "Name = %s\n", name);
 
-       char *filename;
-       xasprintf(&filename, "%s" SLASH "%s", hosts_dir, name);
+       char filename[PATH_MAX];
+       snprintf(filename, sizeof filename, "%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));
+               fclose(f);
                return false;
        }
 
+       snprintf(filename, sizeof filename, "%s" SLASH "tinc-up.invitation", confbase);
+       FILE *fup = fopen(filename, "w");
+       if(!fup) {
+               fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
+               fclose(f);
+               fclose(fh);
+               return false;
+       }
+
+       fprintf(fup, "#!/bin/sh\n");
+       long fuppos = ftell(fup);
+
        // Filter first chunk on approved keywords, split between tinc.conf and hosts/Name
+       // Generate a tinc-up script from Ifconfig and Route keywords.
        // Other chunks go unfiltered to their respective host config files
        const char *p = data;
        char *l, *value;
@@ -588,6 +656,24 @@ make_names:
                        break;
                }
 
+               // Handle Ifconfig and Route statements
+               if(!found) {
+                       if(!strcasecmp(l, "Ifconfig")) {
+                               if(!strcasecmp(value, "dhcp"))
+                                       ifconfig_dhcp(fup);
+                               else if(!strcasecmp(value, "dhcp6"))
+                                       ifconfig_dhcp6(fup);
+                               else if(!strcasecmp(value, "slaac"))
+                                       ifconfig_slaac(fup);
+                               else
+                                       ifconfig_address(fup, value);
+                               continue;
+                       } else if(!strcasecmp(l, "Route")) {
+                               ifconfig_route(fup, value);
+                               continue;
+                       }
+               }
+
                // Ignore unknown and unsafe variables
                if(!found) {
                        fprintf(stderr, "Ignoring unknown variable '%s' in invitation.\n", l);
@@ -602,7 +688,8 @@ make_names:
        }
 
        fclose(f);
-       free(filename);
+       bool valid_tinc_up = ifconfig_footer(fup);
+       fclose(fup);
 
        while(l && !strcasecmp(l, "Name")) {
                if(!check_id(value)) {
@@ -615,7 +702,7 @@ make_names:
                        return false;
                }
 
-               xasprintf(&filename, "%s" SLASH "%s", hosts_dir, value);
+               snprintf(filename, sizeof filename, "%s" SLASH "%s", hosts_dir, value);
                f = fopen(filename, "w");
 
                if(!f) {
@@ -643,7 +730,6 @@ make_names:
                }
 
                fclose(f);
-               free(filename);
        }
 
        // Generate our key and send a copy to the server
@@ -655,8 +741,10 @@ make_names:
        if(!b64key)
                return false;
 
-       xasprintf(&filename, "%s" SLASH "ecdsa_key.priv", confbase);
+       snprintf(filename, sizeof filename, "%s" SLASH "ed25519_key.priv", confbase);
        f = fopenmask(filename, "w", 0600);
+       if(!f)
+               return false;
 
        if(!ecdsa_write_pem_private_key(key, f)) {
                fprintf(stderr, "Error writing private key!\n");
@@ -667,33 +755,34 @@ make_names:
 
        fclose(f);
 
-       fprintf(fh, "ECDSAPublicKey = %s\n", b64key);
+       fprintf(fh, "Ed25519PublicKey = %s\n", b64key);
 
        sptps_send_record(&sptps, 1, b64key, strlen(b64key));
        free(b64key);
+       ecdsa_free(key);
 
-
+#ifndef DISABLE_LEGACY
        rsa_t *rsa = rsa_generate(2048, 0x1001);
-       xasprintf(&filename, "%s" SLASH "rsa_key.priv", confbase);
+       snprintf(filename, sizeof filename, "%s" SLASH "rsa_key.priv", confbase);
        f = fopenmask(filename, "w", 0600);
 
-       rsa_write_pem_private_key(rsa, f);
+       if(!f || !rsa_write_pem_private_key(rsa, f)) {
+               fprintf(stderr, "Could not write private RSA key\n");
+       } else if(!rsa_write_pem_public_key(rsa, fh)) {
+               fprintf(stderr, "Could not write public RSA key\n");
+       }
+
        fclose(f);
 
-       rsa_write_pem_public_key(rsa, fh);
        fclose(fh);
 
-       ecdsa_free(key);
        rsa_free(rsa);
+#endif
 
        check_port(name);
 
-       fprintf(stderr, "Invitation succesfully accepted.\n");
-       shutdown(sock, SHUT_RDWR);
-       success = true;
-
 ask_netname:
-       if(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));
@@ -704,23 +793,78 @@ ask_netname:
 
                line[strlen(line) - 1] = 0;
 
-               char *newbase;
-               xasprintf(&newbase, CONFDIR SLASH "tinc" SLASH "%s", line);
+               char newbase[PATH_MAX];
+               snprintf(newbase, sizeof 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;
-               make_names();
+               make_names(false);
+       }
+
+       char filename2[PATH_MAX];
+       snprintf(filename, sizeof filename, "%s" SLASH "tinc-up.invitation", confbase);
+       snprintf(filename2, sizeof filename2, "%s" SLASH "tinc-up", confbase);
+
+       if(valid_tinc_up) {
+               if(tty) {
+                       FILE *fup = fopen(filename, "r");
+                       if(fup) {
+                               fprintf(stderr, "\nPlease review the following tinc-up script:\n\n");
+
+                               char buf[MAXSIZE];
+                               while(fgets(buf, sizeof buf, fup))
+                                       fputs(buf, stderr);
+                               fclose(fup);
+
+                               int response = 0;
+                               do {
+                                       fprintf(stderr, "\nDo you want to use this script [y]es/[n]o/[e]dit? ");
+                                       response = tolower(getchar());
+                               } while(!strchr("yne", response));
+
+                               fprintf(stderr, "\n");
+
+                               if(response == 'e') {
+                                       char *command;
+#ifndef HAVE_MINGW
+                                       xasprintf(&command, "\"%s\" \"%s\"", getenv("VISUAL") ?: getenv("EDITOR") ?: "vi", filename);
+#else
+                                       xasprintf(&command, "edit \"%s\"", filename);
+#endif
+                                       if(system(command))
+                                               response = 'n';
+                                       else
+                                               response = 'y';
+                                       free(command);
+                               }
+
+                               if(response == 'y') {
+                                       rename(filename, filename2);
+                                       chmod(filename2, 0755);
+                                       fprintf(stderr, "tinc-up enabled.\n");
+                               } else {
+                                       fprintf(stderr, "tinc-up has been left disabled.\n");
+                               }
+                       }
+               } else {
+                       fprintf(stderr, "A tinc-up script was generated, but has been left disabled.\n");
+               }
+       } else {
+               // A placeholder was generated.
+               rename(filename, filename2);
+               chmod(filename2, 0755);
        }
 
+       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) {
+
+static bool invitation_send(void *handle, uint8_t type, const void *data, size_t len) {
        while(len) {
                int result = send(sock, data, len, 0);
                if(result == -1 && errno == EINTR)
@@ -733,7 +877,7 @@ static bool invitation_send(void *handle, uint8_t type, const char *data, size_t
        return true;
 }
 
-static bool invitation_receive(void *handle, uint8_t type, const char *msg, uint16_t len) {
+static bool invitation_receive(void *handle, uint8_t type, const void *msg, uint16_t len) {
        switch(type) {
                case SPTPS_HANDSHAKE:
                        return sptps_send_record(&sptps, 0, cookie, sizeof cookie);
@@ -748,6 +892,12 @@ static bool invitation_receive(void *handle, uint8_t type, const char *msg, uint
                case 1:
                        return finalize_join();
 
+               case 2:
+                       fprintf(stderr, "Invitation succesfully accepted.\n");
+                       shutdown(sock, SHUT_RDWR);
+                       success = true;
+                       break;
+
                default:
                        return false;
        }
@@ -766,7 +916,7 @@ int cmd_join(int argc, char *argv[]) {
        }
 
        // Make sure confbase exists and is accessible.
-       if(strcmp(confdir, confbase) && mkdir(confdir, 0755) && errno != EEXIST) {
+       if(!confbase_given && mkdir(confdir, 0755) && errno != EEXIST) {
                fprintf(stderr, "Could not create directory %s: %s\n", confdir, strerror(errno));
                return 1;
        }
@@ -793,10 +943,8 @@ int cmd_join(int argc, char *argv[]) {
        if(argc > 1) {
                invitation = argv[1];
        } else {
-               if(tty) {
-                       printf("Enter invitation URL: ");
-                       fflush(stdout);
-               }
+               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));
@@ -836,7 +984,7 @@ int cmd_join(int argc, char *argv[]) {
        if(!port || !*port)
                port = "655";
 
-       if(!b64decode(slash, hash, 18) || !b64decode(slash + 24, cookie, 18))
+       if(!b64decode(slash, hash, 24) || !b64decode(slash + 24, cookie, 24))
                goto invalid;
 
        // Generate a throw-away key for the invitation.
@@ -851,16 +999,31 @@ int cmd_join(int argc, char *argv[]) {
        if(!ai)
                return 1;
 
-       sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
+       struct addrinfo *aip = NULL;
+
+next:
+       if(!aip)
+               aip = ai;
+       else {
+               aip = aip->ai_next;
+               if(!aip)
+                       return 1;
+       }
+
+       sock = socket(aip->ai_family, aip->ai_socktype, aip->ai_protocol);
        if(sock <= 0) {
                fprintf(stderr, "Could not open socket: %s\n", strerror(errno));
-               return 1;
+               goto next;
        }
 
-       if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
-               fprintf(stderr, "Could not connect to %s port %s: %s\n", address, port, strerror(errno));
+       if(connect(sock, aip->ai_addr, aip->ai_addrlen)) {
+               char *addrstr, *portstr;
+               sockaddr2str((sockaddr_t *)aip->ai_addr, &addrstr, &portstr);
+               fprintf(stderr, "Could not connect to %s port %s: %s\n", addrstr, portstr, strerror(errno));
+               free(addrstr);
+               free(portstr);
                closesocket(sock);
-               return 1;
+               goto next;
        }
 
        fprintf(stderr, "Connected to %s port %s...\n", address, port);
@@ -873,7 +1036,7 @@ int cmd_join(int argc, char *argv[]) {
        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;
+               goto next;
        }
 
        char hisname[4096] = "";
@@ -882,16 +1045,13 @@ int cmd_join(int argc, char *argv[]) {
        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;
+               goto next;
        }
 
        // Check if the hash of the key he gave us matches the hash in the URL.
        char *fingerprint = line + 2;
-       digest_t *digest = digest_open_by_name("sha256", 18);
-       if(!digest)
-               abort();
-       char hishash[18];
-       if(!digest_create(digest, fingerprint, strlen(fingerprint), hishash)) {
+       char hishash[64];
+       if(sha512(fingerprint, strlen(fingerprint), hishash)) {
                fprintf(stderr, "Could not create digest\n%s\n", line + 2);
                return 1;
        }
@@ -921,8 +1081,14 @@ int cmd_join(int argc, char *argv[]) {
                        return 1;
                }
 
-               if(!sptps_receive_data(&sptps, line, len))
-                       return 1;
+               char *p = line;
+               while(len) {
+                       int done = sptps_receive_data(&sptps, p, len);
+                       if(!done)
+                               return 1;
+                       len -= done;
+                       p += done;
+               }
        }
        
        sptps_stop(&sptps);