/*
meta.c -- handle the meta communication
- Copyright (C) 2000-2009 Guus Sliepen <guus@tinc-vpn.org>,
+ Copyright (C) 2000-2017 Guus Sliepen <guus@tinc-vpn.org>,
2000-2005 Ivo Timmermans
2006 Scott Lamb <slamb@slamb.org>
#include "meta.h"
#include "net.h"
#include "protocol.h"
+#include "proxy.h"
#include "utils.h"
#include "xalloc.h"
int outlen;
int result;
- if(!c) {
- logger(LOG_ERR, "send_meta() called with NULL pointer!");
- abort();
- }
-
ifdebug(META) logger(LOG_DEBUG, "Sending %d bytes of metadata to %s (%s)", length,
- c->name, c->hostname);
+ c->name, c->hostname);
- if(!c->outbuflen)
+ if(!c->outbuflen) {
c->last_flushed_time = now;
+ }
/* Find room in connection's buffer */
if(length + c->outbuflen > c->outbufsize) {
/* Add our data to buffer */
if(c->status.encryptout) {
+ /* Check encryption limits */
+ if((uint64_t)length > c->outbudget) {
+ ifdebug(META) logger(LOG_ERR, "Byte limit exceeded for encryption to %s (%s)", c->name, c->hostname);
+ return false;
+ } else {
+ c->outbudget -= length;
+ }
+
result = EVP_EncryptUpdate(c->outctx, (unsigned char *)c->outbuf + c->outbufstart + c->outbuflen,
- &outlen, (unsigned char *)buffer, length);
+ &outlen, (unsigned char *)buffer, length);
+
if(!result || outlen < length) {
logger(LOG_ERR, "Error while encrypting metadata to %s (%s): %s",
- c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+ c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
return false;
} else if(outlen > length) {
logger(LOG_EMERG, "Encrypted data too long! Heap corrupted!");
abort();
}
+
c->outbuflen += outlen;
} else {
memcpy(c->outbuf + c->outbufstart + c->outbuflen, buffer, length);
bool flush_meta(connection_t *c) {
int result;
-
+
ifdebug(META) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s)",
- c->outbuflen, c->name, c->hostname);
+ c->outbuflen, c->name, c->hostname);
while(c->outbuflen) {
result = send(c->socket, c->outbuf + c->outbufstart, c->outbuflen, 0);
+
if(result <= 0) {
if(!errno || errno == EPIPE) {
ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection closed by %s (%s)",
- c->name, c->hostname);
+ c->name, c->hostname);
} else if(errno == EINTR) {
continue;
} else if(sockwouldblock(sockerrno)) {
- ifdebug(CONNECTIONS) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block",
- c->outbuflen, c->name, c->hostname);
+ ifdebug(META) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block",
+ c->outbuflen, c->name, c->hostname);
return true;
} else {
logger(LOG_ERR, "Flushing meta data to %s (%s) failed: %s", c->name,
- c->hostname, sockstrerror(sockerrno));
+ c->hostname, sockstrerror(sockerrno));
}
return false;
for(node = connection_tree->head; node; node = node->next) {
c = node->data;
- if(c != from && c->status.active)
+ if(c != from && c->status.active) {
send_meta(c, buffer, length);
+ }
}
}
if(lenin <= 0) {
if(!lenin || !errno) {
ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection closed by %s (%s)",
- c->name, c->hostname);
- } else if(sockwouldblock(sockerrno))
+ c->name, c->hostname);
+ } else if(sockwouldblock(sockerrno)) {
return true;
- else
+ } else
logger(LOG_ERR, "Metadata socket read error for %s (%s): %s",
- c->name, c->hostname, sockstrerror(sockerrno));
+ c->name, c->hostname, sockstrerror(sockerrno));
return false;
}
c->buflen += lenin;
while(lenin > 0) {
+ reqlen = 0;
+
+ /* Is it proxy metadata? */
+
+ if(c->allow_request == PROXY) {
+ reqlen = receive_proxy_meta(c);
+
+ if(reqlen < 0) {
+ return false;
+ }
+
+ goto consume;
+ }
+
/* Decrypt */
if(c->status.decryptin && !decrypted) {
+ /* Check decryption limits */
+ if((uint64_t)lenin > c->inbudget) {
+ ifdebug(META) logger(LOG_ERR, "Byte limit exceeded for decryption from %s (%s)", c->name, c->hostname);
+ return false;
+ } else {
+ c->inbudget -= lenin;
+ }
+
result = EVP_DecryptUpdate(c->inctx, (unsigned char *)inbuf, &lenout, (unsigned char *)c->buffer + oldlen, lenin);
+
if(!result || lenout != lenin) {
logger(LOG_ERR, "Error while decrypting metadata from %s (%s): %s",
- c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+ c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
return false;
}
+
memcpy(c->buffer + oldlen, inbuf, lenin);
decrypted = true;
}
if(c->tcplen) {
if(c->tcplen <= c->buflen) {
- receive_tcppacket(c, c->buffer, c->tcplen);
+ if(c->allow_request != ALL) {
+ logger(LOG_ERR, "Got unauthorized TCP packet from %s (%s)", c->name, c->hostname);
+ return false;
+ }
- c->buflen -= c->tcplen;
- lenin -= c->tcplen - oldlen;
- memmove(c->buffer, c->buffer + c->tcplen, c->buflen);
- oldlen = 0;
+ receive_tcppacket(c, c->buffer, c->tcplen);
+ reqlen = c->tcplen;
c->tcplen = 0;
- continue;
- } else {
- break;
}
- }
-
- /* Otherwise we are waiting for a request */
-
- reqlen = 0;
+ } else {
+ /* Otherwise we are waiting for a request */
+
+ for(i = oldlen; i < c->buflen; i++) {
+ if(c->buffer[i] == '\n') {
+ c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */
+ c->reqlen = reqlen = i + 1;
+ break;
+ }
+ }
- for(i = oldlen; i < c->buflen; i++) {
- if(c->buffer[i] == '\n') {
- c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */
- reqlen = i + 1;
- break;
+ if(reqlen && !receive_request(c)) {
+ return false;
}
}
- if(reqlen) {
- c->reqlen = reqlen;
- if(!receive_request(c))
- return false;
+consume:
+ if(reqlen) {
c->buflen -= reqlen;
lenin -= reqlen - oldlen;
memmove(c->buffer, c->buffer + reqlen, c->buflen);
if(c->buflen >= MAXBUFSIZE) {
logger(LOG_ERR, "Metadata read buffer overflow for %s (%s)",
- c->name, c->hostname);
+ c->name, c->hostname);
return false;
}