static int dnszones_init(struct dnszones *dnszones, const char *cfgdir, const char *vardir, const char *warning, int (op)()) {
int r;
long long basefd;
byte_zero(dnszones, sizeof (struct dnszones));
/* warning */
dnszones->warning = warning;
basefd = open_cwd();
if (basefd == -1) return -1;
if (chdir(cfgdir) == -1) {
close(basefd);
return -1;
}
r = op(dnszones, cfgdir, vardir, warning);
if (fchdir(basefd) == -1) r = -1;
close(basefd);
return r;
}
int main(int argc, char **argv) {
char *x;
const char *keydir = 0;
long long i;
struct pollfd p[6];
struct pollfd *q;
struct pollfd *watch0;
struct pollfd *watch1;
struct pollfd *watchtochild;
struct pollfd *watchfromchild1;
struct pollfd *watchfromchild2;
struct pollfd *watchselfpipe;
int exitsignal, exitcode;
signal(SIGPIPE, SIG_IGN);
signal(SIGALRM, timeout);
log_init(0, "tinysshd", 0, 0);
if (argc < 2) die_usage(USAGE);
if (!argv[0]) die_usage(USAGE);
for (;;) {
if (!argv[1]) break;
if (argv[1][0] != '-') break;
x = *++argv;
if (x[0] == '-' && x[1] == 0) break;
if (x[0] == '-' && x[1] == '-' && x[2] == 0) break;
while (*++x) {
if (*x == 'q') { flagverbose = 0; continue; }
if (*x == 'Q') { flagverbose = 1; continue; }
if (*x == 'v') { if (flagverbose >= 2) flagverbose = 3; else flagverbose = 2; continue; }
if (*x == 'o') { cryptotypeselected |= sshcrypto_TYPEOLDCRYPTO; continue; }
if (*x == 'O') { cryptotypeselected &= ~sshcrypto_TYPEOLDCRYPTO; continue; }
if (*x == 's') { cryptotypeselected |= sshcrypto_TYPENEWCRYPTO; continue; }
if (*x == 'S') { cryptotypeselected &= ~sshcrypto_TYPENEWCRYPTO; continue; }
if (*x == 'p') { cryptotypeselected |= sshcrypto_TYPEPQCRYPTO; continue; }
if (*x == 'P') { cryptotypeselected &= ~sshcrypto_TYPEPQCRYPTO; continue; }
if (*x == 'l') { flaglogger = 1; continue; }
if (*x == 'L') { flaglogger = 0; continue; }
if (*x == 'x') {
if (x[1]) { channel_subsystem_add(x + 1); break; }
if (argv[1]) { channel_subsystem_add(*++argv); break; }
}
die_usage(USAGE);
}
}
keydir = *++argv; if (!keydir) die_usage(USAGE);
log_init(flagverbose, "tinysshd", 1, flaglogger);
connectioninfo(channel.localip, channel.localport, channel.remoteip, channel.remoteport);
log_i4("connection from ", channel.remoteip, ":", channel.remoteport);
channel_subsystem_log();
global_init();
blocking_disable(0);
blocking_disable(1);
blocking_disable(2);
/* get server longterm keys */
fdwd = open_cwd();
if (fdwd == -1) die_fatal("unable to open current directory", 0, 0);
if (chdir(keydir) == -1) die_fatal("unable to chdir to", keydir, 0);
for (i = 0; sshcrypto_keys[i].name; ++i) sshcrypto_keys[i].sign_flagserver |= sshcrypto_kexs[i].cryptotype & cryptotypeselected;
for (i = 0; sshcrypto_keys[i].name; ++i) sshcrypto_keys[i].sign_flagclient |= sshcrypto_kexs[i].cryptotype & cryptotypeselected;
for (i = 0; sshcrypto_kexs[i].name; ++i) sshcrypto_kexs[i].flagenabled |= sshcrypto_kexs[i].cryptotype & cryptotypeselected;
for (i = 0; sshcrypto_ciphers[i].name; ++i) sshcrypto_ciphers[i].flagenabled |= sshcrypto_ciphers[i].cryptotype & cryptotypeselected;
/* read public keys */
for (i = 0; sshcrypto_keys[i].name; ++i) {
if (!sshcrypto_keys[i].sign_flagserver) continue;
if (load(sshcrypto_keys[i].sign_publickeyfilename, sshcrypto_keys[i].sign_publickey, sshcrypto_keys[i].sign_publickeybytes) == -1) {
sshcrypto_keys[i].sign_flagserver = 0;
if (errno == ENOENT) continue;
die_fatal("unable to read public key from file", keydir, sshcrypto_keys[i].sign_publickeyfilename);
}
}
if (fchdir(fdwd) == -1) die_fatal("unable to change directory to working directory", 0, 0);
close(fdwd);
/* set timeout */
alarm(60);
/* send and receive hello */
if (!packet_hello_send()) die_fatal("unable to send hello-string", 0, 0);
if (!packet_hello_receive()) die_fatal("unable to receive hello-string", 0, 0);
/* send and receive kex */
if (!packet_kex_send()) die_fatal("unable to send kex-message", 0, 0);
if (!packet_kex_receive()) die_fatal("unable to receive kex-message", 0, 0);
rekeying:
/* rekeying */
alarm(60);
if (packet.flagrekeying == 1) {
buf_purge(&packet.kexrecv);
buf_put(&packet.kexrecv, b1.buf, b1.len);
if (!packet_kex_send()) die_fatal("unable to send kex-message", 0, 0);
}
/* send and receive kexdh */
if (!packet_kexdh(keydir, &b1, &b2)) die_fatal("unable to subprocess kexdh", 0, 0);
if (packet.flagkeys) log_d1("rekeying: done");
packet.flagkeys = 1;
/* note: comunication is encrypted */
/* authentication + authorization */
if (packet.flagauthorized == 0) {
if (!packet_auth(&b1, &b2)) die_fatal("authentication failed", 0, 0);
packet.flagauthorized = 1;
}
/* note: user is authenticated and authorized */
alarm(3600);
/* main loop */
for (;;) {
if (channel_iseof())
if (!packet.sendbuf.len)
if (packet.flagchanneleofreceived)
break;
watch0 = watch1 = 0;
watchtochild = watchfromchild1 = watchfromchild2 = 0;
watchselfpipe = 0;
q = p;
if (packet_sendisready()) { watch1 = q; q->fd = 1; q->events = POLLOUT; ++q; }
if (packet_recvisready()) { watch0 = q; q->fd = 0; q->events = POLLIN; ++q; }
if (channel_writeisready()) { watchtochild = q; q->fd = channel_getfd0(); q->events = POLLOUT; ++q; }
if (channel_readisready() && packet_putisready()) { watchfromchild1 = q; q->fd = channel_getfd1(); q->events = POLLIN; ++q; }
if (channel_extendedreadisready() && packet_putisready()) { watchfromchild2 = q; q->fd = channel_getfd2(); q->events = POLLIN; ++q; }
if (selfpipe[0] != -1) { watchselfpipe = q; q->fd = selfpipe[0]; q->events = POLLIN; ++q; }
if (poll(p, q - p, 60000) < 0) {
watch0 = watch1 = 0;
watchtochild = watchfromchild1 = watchfromchild2 = 0;
watchselfpipe = 0;
}
else {
if (watch0) if (!watch0->revents) watch0 = 0;
if (watch1) if (!watch1->revents) watch1 = 0;
if (watchfromchild1) if (!watchfromchild1->revents) watchfromchild1 = 0;
if (watchfromchild2) if (!watchfromchild2->revents) watchfromchild2 = 0;
if (watchtochild) if (!watchtochild->revents) watchtochild = 0;
if (watchselfpipe) if (!watchselfpipe->revents) watchselfpipe = 0;
}
if (watchtochild) {
/* write data to child */
if (!channel_write()) die_fatal("unable to write data to child", 0, 0);
/* try to adjust window */
if (!packet_channel_send_windowadjust(&b1)) die_fatal("unable to send data to network", 0, 0);
}
/* read data from child */
if (watchfromchild1) packet_channel_send_data(&b2);
if (watchfromchild2) packet_channel_send_extendeddata(&b2);
/* check child */
if (channel_iseof()) {
if (selfpipe[0] == -1) if (open_pipe(selfpipe) == -1) die_fatal("unable to open pipe", 0, 0);
signal(SIGCHLD, trigger);
if (channel_waitnohang(&exitsignal, &exitcode)) {
packet_channel_send_eof(&b2);
if (!packet_channel_send_close(&b2, exitsignal, exitcode)) die_fatal("unable to close channel", 0, 0);
}
}
/* send data to network */
if (watch1) if (!packet_send()) die_fatal("unable to send data to network", 0, 0);
/* receive data from network */
if (watch0) {
alarm(3600); /* refresh timeout */
if (!packet_recv()) {
if (channel_iseof()) break; /* XXX */
die_fatal("unable to receive data from network", 0, 0);
}
}
/* process packets */
for (;;) {
if (!packet_get(&b1, 0)) {
if (!errno) break;
die_fatal("unable to get packets from network", 0, 0);
}
if (b1.len < 1) break; /* XXX */
switch (b1.buf[0]) {
case SSH_MSG_CHANNEL_OPEN:
if (!packet_channel_open(&b1, &b2)) die_fatal("unable to open channel", 0, 0);
break;
case SSH_MSG_CHANNEL_REQUEST:
if (!packet_channel_request(&b1, &b2)) die_fatal("unable to handle channel-request", 0, 0);
break;
case SSH_MSG_CHANNEL_DATA:
if (!packet_channel_recv_data(&b1)) die_fatal("unable to handle channel-data", 0, 0);
break;
case SSH_MSG_CHANNEL_EXTENDED_DATA:
if (!packet_channel_recv_extendeddata(&b1)) die_fatal("unable to handle channel-extended-data", 0, 0);
break;
case SSH_MSG_CHANNEL_WINDOW_ADJUST:
if (!packet_channel_recv_windowadjust(&b1)) die_fatal("unable to handle channel-window-adjust", 0, 0);
break;
case SSH_MSG_CHANNEL_EOF:
if (!packet_channel_recv_eof(&b1)) die_fatal("unable to handle channel-eof", 0, 0);
break;
case SSH_MSG_CHANNEL_CLOSE:
if (!packet_channel_recv_close(&b1)) die_fatal("unable to handle channel-close", 0, 0);
break;
case SSH_MSG_KEXINIT:
goto rekeying;
default:
if (!packet_unimplemented(&b1)) die_fatal("unable to send SSH_MSG_UNIMPLEMENTED message", 0, 0);
}
}
}
log_i1("finished");
global_die(0); return 111;
}
int main(int argc,char **argv)
{
long long hellopackets;
long long r;
long long nextaction;
signal(SIGPIPE,SIG_IGN);
if (!argv[0]) die_usage(0);
for (;;) {
char *x;
if (!argv[1]) break;
if (argv[1][0] != '-') break;
x = *++argv;
if (x[0] == '-' && x[1] == 0) break;
if (x[0] == '-' && x[1] == '-' && x[2] == 0) break;
while (*++x) {
if (*x == 'q') { flagverbose = 0; continue; }
if (*x == 'Q') { flagverbose = 1; continue; }
if (*x == 'v') { if (flagverbose == 2) flagverbose = 3; else flagverbose = 2; continue; }
if (*x == 'c') {
if (x[1]) { keydir = x + 1; break; }
if (argv[1]) { keydir = *++argv; break; }
}
die_usage(0);
}
}
if (!nameparse(servername,*++argv)) die_usage("sname must be at most 255 bytes, at most 63 bytes between dots");
if (!hexparse(serverlongtermpk,32,*++argv)) die_usage("pk must be exactly 64 hex characters");
if (!multiipparse(serverip,*++argv)) die_usage("ip must be a comma-separated series of IPv4 addresses");
if (!portparse(serverport,*++argv)) die_usage("port must be an integer between 0 and 65535");
if (!hexparse(serverextension,16,*++argv)) die_usage("ext must be exactly 32 hex characters");
if (!*++argv) die_usage("missing prog");
for (;;) {
r = open_read("/dev/null");
if (r == -1) die_fatal("unable to open /dev/null",0,0);
if (r > 9) { close(r); break; }
}
if (keydir) {
fdwd = open_cwd();
if (fdwd == -1) die_fatal("unable to open current working directory",0,0);
if (chdir(keydir) == -1) die_fatal("unable to change to directory",keydir,0);
if (load("publickey",clientlongtermpk,sizeof clientlongtermpk) == -1) die_fatal("unable to read public key from",keydir,0);
if (load(".expertsonly/secretkey",clientlongtermsk,sizeof clientlongtermsk) == -1) die_fatal("unable to read secret key from",keydir,0);
} else {
crypto_box_keypair(clientlongtermpk,clientlongtermsk);
}
crypto_box_keypair(clientshorttermpk,clientshorttermsk);
clientshorttermnonce = randommod(281474976710656LL);
crypto_box_beforenm(clientshortserverlong,serverlongtermpk,clientshorttermsk);
crypto_box_beforenm(clientlongserverlong,serverlongtermpk,clientlongtermsk);
udpfd = socket_udp();
if (udpfd == -1) die_fatal("unable to create socket",0,0);
for (hellopackets = 0;hellopackets < NUMIP;++hellopackets) {
recent = nanoseconds();
/* send a Hello packet: */
clientextension_init();
clientshorttermnonce_update();
byte_copy(nonce,16,"CurveCP-client-H");
uint64_pack(nonce + 16,clientshorttermnonce);
byte_copy(packet,8,"QvnQ5XlH");
byte_copy(packet + 8,16,serverextension);
byte_copy(packet + 24,16,clientextension);
byte_copy(packet + 40,32,clientshorttermpk);
byte_copy(packet + 72,64,allzero);
byte_copy(packet + 136,8,nonce + 16);
crypto_box_afternm(text,allzero,96,nonce,clientshortserverlong);
byte_copy(packet + 144,80,text + 16);
socket_send(udpfd,packet,224,serverip + 4 * hellopackets,serverport);
nextaction = recent + hellowait[hellopackets] + randommod(hellowait[hellopackets]);
for (;;) {
long long timeout = nextaction - recent;
if (timeout <= 0) break;
p[0].fd = udpfd;
p[0].events = POLLIN;
if (poll(p,1,timeout / 1000000 + 1) < 0) p[0].revents = 0;
do { /* try receiving a Cookie packet: */
if (!p[0].revents) break;
r = socket_recv(udpfd,packet,sizeof packet,packetip,packetport);
if (r != 200) break;
if (!(byte_isequal(packetip,4,serverip + 4 * hellopackets) &
byte_isequal(packetport,2,serverport) &
byte_isequal(packet,8,"RL3aNMXK") &
byte_isequal(packet + 8,16,clientextension) &
byte_isequal(packet + 24,16,serverextension)
)) break;
byte_copy(nonce,8,"CurveCPK");
byte_copy(nonce + 8,16,packet + 40);
byte_zero(text,16);
byte_copy(text + 16,144,packet + 56);
if (crypto_box_open_afternm(text,text,160,nonce,clientshortserverlong)) break;
byte_copy(servershorttermpk,32,text + 32);
byte_copy(servercookie,96,text + 64);
byte_copy(serverip,4,serverip + 4 * hellopackets);
goto receivedcookie;
} while (0);
recent = nanoseconds();
}
}
errno = ETIMEDOUT; die_fatal("no response from server",0,0);
receivedcookie:
crypto_box_beforenm(clientshortservershort,servershorttermpk,clientshorttermsk);
byte_copy(nonce,8,"CurveCPV");
if (keydir) {
if (safenonce(nonce + 8,0) == -1) die_fatal("nonce-generation disaster",0,0);
} else {
randombytes(nonce + 8,16);
}
byte_zero(text,32);
byte_copy(text + 32,32,clientshorttermpk);
crypto_box_afternm(text,text,64,nonce,clientlongserverlong);
byte_copy(vouch,16,nonce + 8);
byte_copy(vouch + 16,48,text + 16);
/* server is responding, so start child: */
if (open_pipe(tochild) == -1) die_fatal("unable to create pipe",0,0);
if (open_pipe(fromchild) == -1) die_fatal("unable to create pipe",0,0);
child = fork();
if (child == -1) die_fatal("unable to fork",0,0);
if (child == 0) {
if (keydir) if (fchdir(fdwd) == -1) die_fatal("unable to chdir to original directory",0,0);
close(8);
if (dup(tochild[0]) != 8) die_fatal("unable to dup",0,0);
close(9);
if (dup(fromchild[1]) != 9) die_fatal("unable to dup",0,0);
/* XXX: set up environment variables */
signal(SIGPIPE,SIG_DFL);
execvp(*argv,argv);
die_fatal("unable to run",*argv,0);
}
close(fromchild[1]);
close(tochild[0]);
for (;;) {
p[0].fd = udpfd;
p[0].events = POLLIN;
p[1].fd = fromchild[0];
p[1].events = POLLIN;
if (poll(p,2,-1) < 0) {
p[0].revents = 0;
p[1].revents = 0;
}
do { /* try receiving a Message packet: */
if (!p[0].revents) break;
r = socket_recv(udpfd,packet,sizeof packet,packetip,packetport);
if (r < 80) break;
if (r > 1152) break;
if (r & 15) break;
packetnonce = uint64_unpack(packet + 40);
if (flagreceivedmessage && packetnonce <= receivednonce) break;
if (!(byte_isequal(packetip,4,serverip + 4 * hellopackets) &
byte_isequal(packetport,2,serverport) &
byte_isequal(packet,8,"RL3aNMXM") &
byte_isequal(packet + 8,16,clientextension) &
byte_isequal(packet + 24,16,serverextension)
)) break;
byte_copy(nonce,16,"CurveCP-server-M");
byte_copy(nonce + 16,8,packet + 40);
byte_zero(text,16);
byte_copy(text + 16,r - 48,packet + 48);
if (crypto_box_open_afternm(text,text,r - 32,nonce,clientshortservershort)) break;
if (!flagreceivedmessage) {
flagreceivedmessage = 1;
randombytes(clientlongtermpk,sizeof clientlongtermpk);
randombytes(vouch,sizeof vouch);
randombytes(servername,sizeof servername);
randombytes(servercookie,sizeof servercookie);
}
receivednonce = packetnonce;
text[31] = (r - 64) >> 4;
/* child is responsible for reading all data immediately, so we won't block: */
if (writeall(tochild[1],text + 31,r - 63) == -1) goto done;
} while (0);
do { /* try receiving data from child: */
long long i;
if (!p[1].revents) break;
r = read(fromchild[0],childbuf,sizeof childbuf);
if (r == -1) if (errno == EINTR || errno == EWOULDBLOCK || errno == EAGAIN) break;
if (r <= 0) goto done;
childbuflen = r;
for (i = 0;i < childbuflen;++i) {
if (childmessagelen < 0) goto done;
if (childmessagelen >= sizeof childmessage) goto done;
childmessage[childmessagelen++] = childbuf[i];
if (childmessage[0] & 128) goto done;
if (childmessagelen == 1 + 16 * (unsigned long long) childmessage[0]) {
clientextension_init();
clientshorttermnonce_update();
uint64_pack(nonce + 16,clientshorttermnonce);
if (flagreceivedmessage) {
r = childmessagelen - 1;
if (r < 16) goto done;
if (r > 1088) goto done;
byte_copy(nonce,16,"CurveCP-client-M");
byte_zero(text,32);
byte_copy(text + 32,r,childmessage + 1);
crypto_box_afternm(text,text,r + 32,nonce,clientshortservershort);
byte_copy(packet,8,"QvnQ5XlM");
byte_copy(packet + 8,16,serverextension);
byte_copy(packet + 24,16,clientextension);
byte_copy(packet + 40,32,clientshorttermpk);
byte_copy(packet + 72,8,nonce + 16);
byte_copy(packet + 80,r + 16,text + 16);
socket_send(udpfd,packet,r + 96,serverip,serverport);
} else {
r = childmessagelen - 1;
if (r < 16) goto done;
if (r > 640) goto done;
byte_copy(nonce,16,"CurveCP-client-I");
byte_zero(text,32);
byte_copy(text + 32,32,clientlongtermpk);
byte_copy(text + 64,64,vouch);
byte_copy(text + 128,256,servername);
byte_copy(text + 384,r,childmessage + 1);
crypto_box_afternm(text,text,r + 384,nonce,clientshortservershort);
byte_copy(packet,8,"QvnQ5XlI");
byte_copy(packet + 8,16,serverextension);
byte_copy(packet + 24,16,clientextension);
byte_copy(packet + 40,32,clientshorttermpk);
byte_copy(packet + 72,96,servercookie);
byte_copy(packet + 168,8,nonce + 16);
byte_copy(packet + 176,r + 368,text + 16);
socket_send(udpfd,packet,r + 544,serverip,serverport);
}
childmessagelen = 0;
}
}
} while (0);
}
done:
do {
r = waitpid(child,&childstatus,0);
} while (r == -1 && errno == EINTR);
if (!WIFEXITED(childstatus)) { errno = 0; die_fatal("process killed by signal",0,0); }
return WEXITSTATUS(childstatus);
}
