/*
- * Encrypting tunnel for userv-ipif tunnels, actual implementation
- *
+ * Encrypting tunnel for userv-ipif tunnels, actual core implementation
+ */
+/*
* usage:
- * udptunnel-forwarder <public-local-fd> <private-in-fd> <private-out-fd>
- * <mtu> <keepalive> <timeout>
+ * udptunnel-forwarder <optchars>
+ * <public-local-fd> <private-in-fd> <private-out-fd>
+ * <encdec-keys-fd>
+ * <mtu> <keepalive> <timeout> <reannounce>
* <public-remote-addr> [<public-remote-port>]
- * <encdec-keys-fd> <encdec-keys-write>
- * <mech1> [<mech1-params> ...]
- * <mech2> [<mech2-params> ...]
+ * |<mech1> [<mech1-params> ...]
+ * |<mech2> [<mech2-params> ...]
* ''
*
* Remote addr may '' to mean wait to receive a packet and reply to
* whereever we get a good packet from first, in which case port
* should not be specified.
*
- * <enc-keys-write> is '' to mean read, anything else to mean write.
+ * <optchars> is zero or more of
+ * w means generate and write encdec keys, rather than reading them
+ * K means do crypto debug (use with care!)
+ *
+ * encdec keys datastream has keys for packets from key datastream
+ * writer to reader first, then keys for packets from reader to
+ * writer.
*
- * Every must be numeric. There is very little argument checking.
+ * Every addr or port must be numeric. There is very little argument checking.
*
* Exit status:
* SIGALARM timed out
* 12 usage error
* 16 bad trouble
*/
+/*
+ * Copyright (C) 2000,2003 Ian Jackson
+ * This file is part of ipif, part of userv-utils
+ *
+ * This 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 userv-utils; if not, write to the Free Software
+ * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
#include <sys/socket.h>
#include <netinet/in.h>
#include <unistd.h>
#include <fcntl.h>
-#include "mech.h"
+#include "forwarder.h"
#define MAXMECHS 10
-#define PROGRAM "udptunnel-forwarder"
-char programid[SYS_NMLN+sizeof(PROGRAM)+3];
-static const char *const *argv;
static size_t buffer_size;
+static struct utsname uname_result;
+static const char *opt_chars;
static int public_local_fd, private_in_fd, private_out_fd;
-static int mtu2, keepalive, timeout;
+static int mtu2, keepalive, timeout, reannounce;
static int public_remote_specd;
static struct sockaddr_in public_remote;
-static int encdec_keys_fd, encdec_keys_write;
+static int encdec_keys_fd, encdec_keys_write, crypto_debug;
static int n_mechs;
static const struct mechanism *mechs[MAXMECHS];
static time_t nextsendka;
-
-void arg_assert_fail(const char *msg) {
- fprintf(stderr, PROGRAM ": argument error: %s\n",msg);
- exit(12);
-}
-
-void sysfail(const char *msg) {
- fprintf(stderr, "%s: fatal system error: %s: %s\n", programid, msg, strerror(errno));
- exit(8);
-}
-
-void fail(const char *msg) {
- fprintf(stderr, "%s: fatal error: %s\n", programid, msg);
- exit(4);
+static void cdebug(int mechno /*or -1*/, const char *msg) {
+ if (!crypto_debug) return;
+ printf("%-8.8s: CRYPTO: %-20s %s\n",
+ uname_result.nodename,
+ mechno >= 0 ? mechs[mechno]->name : "",
+ msg);
}
-void sysdiag(const char *msg) {
- fprintf(stderr, "%s: system/network error: %s: %s\n", programid, msg, strerror(errno));
-}
+static void cdebughex(int mechno /*or -1*/, const char *msg, const void *ptr,
+ size_t sz, size_t skipbefore,
+ int spc_offset, int dot_offset) {
+ const unsigned char *p;
+ size_t i;
+ unsigned j= dot_offset;
+
+ if (!crypto_debug) return;
+ printf("%-8.8s: CRYPTO: %-20s %-10s",
+ uname_result.nodename,
+ mechno >= 0 ? mechs[mechno]->name : "",
+ msg);
-void diag(const char *msg) {
- fprintf(stderr, "%s: %s\n", programid, msg);
-}
+ for (i=0; i<spc_offset; i++, j++) fputs(j&3 ? " " : " ",stdout);
+ for (i=0; i<skipbefore; i++, j++) fputs(j&3 ? ".." : " ..",stdout);
+ for (i=0, p=ptr; i<sz; i++, j++, p++) printf(j&3 ? "%02x" : " %02x",*p);
-time_t now(void) {
- time_t r;
- if (time(&r) == (time_t)-1) sysfail("get time of day");
- return r;
+ fputc('\n',stdout);
}
-void *xmalloc(size_t sz) {
- void *r;
- r= malloc(sz);
- if (!r) sysfail("allocate memory");
- return r;
+static void cdebugbuf(int mechno /*or -1*/, const char *msg,
+ const struct buffer *buf, int spc_offset, int dot_offset) {
+ cdebughex(mechno, msg, buf->start, buf->size, buf->start - buf->base,
+ spc_offset, dot_offset);
}
void get_random(void *ptr, size_t sz) {
}
r= fread(ptr,1,sz,randfile);
- if (r == sz) return;
- (ferror(randfile) ? sysfail : fail)("cannot read random number generator");
-}
+ if (r != sz)
+ (ferror(randfile) ? sysfail : fail)("cannot read random number generator");
-const char *getarg_string(void) {
- const char *arg;
-
- arg= *++argv;
- arg_assert(arg);
- return arg;
+ cdebughex(-1, "get_random", ptr, sz, 0,0,0);
}
-unsigned long getarg_ulong(void) {
- char *ep;
- unsigned long ul;
-
- ul= strtoul(getarg_string(),&ep,0);
- arg_assert(!*ep);
- return ul;
+void random_key(void *ptr, size_t sz) {
+ if (encdec_keys_write) {
+ get_random(ptr,sz);
+ write_must(encdec_keys_fd,ptr,sz,"write keys datastream");
+ } else {
+ read_must(encdec_keys_fd,ptr,sz,"read keys datastream");
+ cdebughex(-1, "random_key", ptr, sz, 0,0,0);
+ }
}
+
static void setnonblock(int fd, int nonblock) {
int r;
if (r==-1) sysfail("fcntl F_SETFL");
}
-static const struct mechanism *getarg_mech(void) {
- const char *name;
+static const struct mechanism *find_mech(const char *name) {
const struct mechanism *mech, *const *mechlist;
- name= getarg_string();
-
for (mechlist= mechanismlists;
*mechlist;
mechlist++)
static void inbound(void) {
static int any_recvd;
+ static time_t nextreann;
+ static unsigned long npackets, nbytes;
struct sockaddr_in this_saddr;
int r, i, different, this_saddrlen;
const char *emsg;
- alarm(timeout);
-
+ buf_in.start= buf_in.base+1;
+ buf_in.size= buffer_size-2;
+
setnonblock(public_local_fd,1);
this_saddrlen= sizeof(this_saddr);
- r= recvfrom(public_local_fd, buf_in.base, buffer_size-1, 0,
+ r= recvfrom(public_local_fd, buf_in.start, buf_in.size, 0,
&this_saddr, &this_saddrlen);
if (!r) { diag("empty ciphertext"); return; }
if (r<0) {
- if (errno != EAGAIN && errno != EINTR) sysdiag("receive");
+ if (errno != EAGAIN && errno != EINTR) { sysdiag("receive"); sleep(1); }
return;
}
if (this_saddr.sin_family != AF_INET) {
- fprintf(stderr,"%s: received unknown AF %lu",
+ fprintf(stderr,"%s: received unknown AF %lu\n",
programid, (unsigned long)this_saddr.sin_family);
return;
}
assert(this_saddrlen == sizeof(this_saddr));
- buf_in.size= buffer_size;
- buf_in.start= buf_in.base;
+ assert(r <= buf_in.size);
+ buf_in.size= r;
+ cdebugbuf(-1, "decode", &buf_in, 3,0);
for (i=n_mechs-1; i>=0; i--) {
emsg= mechs[i]->decode(md_in[i],&buf_in);
if (emsg) {
- fprintf(stderr, "%s: bad packet: %s: %s\n", programid, mechs[i]->name, emsg);
+ if (*emsg)
+ fprintf(stderr, "%s: bad packet: %s: %s\n",
+ programid, mechs[i]->name, emsg);
+ else
+ cdebug(i,"silently discarded");
return;
}
+ cdebugbuf(i, "decode", &buf_in, 3,0);
}
- different= !public_remote_specd ||
- memcmp(&this_saddr,&public_remote,sizeof(this_saddr));
+ npackets++;
+ nbytes += buf_in.size;
+ alarm(timeout);
+
+ different= (!public_remote_specd ||
+ public_remote.sin_addr.s_addr != this_saddr.sin_addr.s_addr ||
+ public_remote.sin_port != this_saddr.sin_port);
if (different) {
if (public_remote_specd==2) {
- fprintf(stderr, "%s: packet from unexpected sender %s:%lu",
+ fprintf(stderr, "%s: packet from unexpected sender %s:%lu\n",
programid, inet_ntoa(this_saddr.sin_addr),
- (unsigned long)this_saddr.sin_port);
+ (unsigned long)ntohs(this_saddr.sin_port));
return;
}
- fprintf(stderr, "%s: tunnel open with peer %s:%lu",
+ fprintf(stderr, "%s: tunnel open with peer %s:%lu\n",
programid, inet_ntoa(this_saddr.sin_addr),
- (unsigned long)this_saddr.sin_port);
+ (unsigned long)ntohs(this_saddr.sin_port));
nextsendka= now();
public_remote_specd= 1;
memcpy(&public_remote,&this_saddr,sizeof(public_remote));
diag("tunnel open");
+ } else if (reannounce && now() >= nextreann) {
+
+ fprintf(stderr, "%s: tunnel still open: received %lu packets, %lu bytes\n",
+ programid, npackets, nbytes);
+
+ } else {
+
+ goto no_set_reann; /* only reset this if we don't print a message. */
+
}
- any_recvd= 1;
+ if (reannounce)
+ nextreann= now() + reannounce;
- buf_in.start[buf_in.size]= 0300;
- *--buf_in.start= 0300;
- buf_in.size+= 2;
+no_set_reann:
- setnonblock(private_in_fd,0);
- while (buf_in.size) {
- r= write(private_in_fd, buf_in.start, buf_in.size);
- assert(r && r <= buf_in.size);
- if (r<0) {
- if (errno == EINTR) continue;
- sysfail("write down");
- }
- buf_in.start += r;
- buf_in.size -= r;
+ any_recvd= 1;
+
+ if (!buf_in.size || *buf_in.start != 0300) {
+ *--buf_in.start= 0300;
+ buf_in.size++;
}
+ if (buf_in.start[buf_in.size-1] != 0300) {
+ buf_in.start[buf_in.size++]= 0300;
+ }
+
+ setnonblock(private_in_fd,0);
+ write_must(private_in_fd, buf_in.start, buf_in.size, "write down");
}
static void sendpacket(const unsigned char *message, size_t size) {
nextsendka= now() + keepalive;
- for (i=0; i<n_mechs; i++) mechs[i]->encode(md_out[i],&buf_out);
+ cdebugbuf(-1, "encode", &buf_out, 4,0);
+ for (i=0; i<n_mechs; i++) {
+ mechs[i]->encode(md_out[i],&buf_out);
+ cdebugbuf(i, "encode", &buf_out, 4,0);
+ }
assert(public_remote_specd);
setnonblock(public_local_fd,1);
after_eaten= accum_buf;
while ((delim= memchr(after_eaten, 0300, accum_used))) {
this_packet= delim - after_eaten;
- sendpacket(after_eaten, this_packet);
+ if (this_packet) sendpacket(after_eaten, this_packet);
accum_used -= this_packet+1;
after_eaten = delim+1;
}
int main(int argc, const char *const *const argv_in) {
const char *arg;
+ const char *const *argv_save;
+ const char *const *argv_done;
struct pollfd pollfds[2];
- struct utsname uname_result;
int i, polltimeout, r;
time_t tnow;
if (uname(&uname_result)) { perror(PROGRAM ": uname failed"); exit(16); }
sprintf(programid, PROGRAM ": %.*s", SYS_NMLN, uname_result.nodename);
-
+
+ opt_chars= getarg_string();
+ encdec_keys_write= !!strchr(opt_chars,'w');
+ crypto_debug= !!strchr(opt_chars,'K');
+
public_local_fd= getarg_ulong();
+ private_in_fd= getarg_ulong();
+ private_out_fd= getarg_ulong();
+ encdec_keys_fd= getarg_ulong();
+
mtu2= getarg_ulong() * 2;
keepalive= getarg_ulong();
timeout= getarg_ulong();
- private_in_fd= getarg_ulong();
- private_out_fd= getarg_ulong();
+ reannounce= getarg_ulong();
arg= getarg_string();
if (*arg) {
public_remote_specd= 1;
+ public_remote.sin_family= AF_INET;
arg_assert(inet_aton(arg,&public_remote.sin_addr));
- public_remote.sin_port= getarg_ulong();
+ public_remote.sin_port= htons(getarg_ulong());
}
- encdec_keys_fd= getarg_ulong();
- encdec_keys_write= !!*getarg_string();
+ if (crypto_debug) {
+ diag("crypto debugging enabled!");
+ setvbuf(stdout,0,_IOLBF,0);
+ }
maxprefix= 0;
- for (i=0; i<n_mechs; i++) mechs[i]= getarg_mech();
- for (i=0; i<n_mechs; i++) mechs[i]->encsetup(&md_in[i], &maxprefix, &maxsuffix);
- for (i=0; i<n_mechs; i++) mechs[i]->decsetup(&md_out[i]);
+ i= 0;
+ while ((arg= *++argv)) {
+ arg_assert(*arg++ == '|');
+ arg_assert(i <= MAXMECHS);
+ mechs[i]= find_mech(arg);
+
+ cdebug(i,"writer->reader setup");
+ argv_save= argv;
+
+ if (encdec_keys_write)
+ mechs[i]->encsetup(&md_out[i], &maxprefix, &maxsuffix);
+ else
+ mechs[i]->decsetup(&md_in[i]);
+
+ argv_done= argv;
+ argv= argv_save;
+ cdebug(i,"reader->writer setup");
+
+ if (encdec_keys_write)
+ mechs[i]->decsetup(&md_in[i]);
+ else
+ mechs[i]->encsetup(&md_out[i], &maxprefix, &maxsuffix);
+
+ assert(argv == argv_done);
+
+ i++;
+ }
+ n_mechs= i;
if (maxprefix<1) maxprefix= 1;
if (maxsuffix<1) maxsuffix= 1;
if (keepalive) {
tnow= now();
- if (tnow >= nextsendka) sendpacket("\300",1);
+ if (tnow >= nextsendka && public_remote_specd) sendpacket("\300",1);
polltimeout= (nextsendka - tnow)*1000;
} else {
polltimeout= -1;
if (r==-1 && errno==EINTR) continue;
if (r==-1) sysfail("poll");
- if (pollfds[0].revents & POLLIN) inbound();
- if (pollfds[1].revents & POLLOUT) outbound();
+ if (pollfds[0].revents & (POLLIN|POLLERR)) inbound();
+ if (pollfds[1].revents & (POLLIN|POLLERR)) outbound();
}
}
~ian / userv-utils.git / blobdiff