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proxy_common.c
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proxy_common.c
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/*
* UFTP - UDP based FTP with multicast
*
* Copyright (C) 2001-2015 Dennis A. Bush, Jr. [email protected]
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*
* Additional permission under GNU GPL version 3 section 7
*
* If you modify this program, or any covered work, by linking or
* combining it with the OpenSSL project's OpenSSL library (or a
* modified version of that library), containing parts covered by the
* terms of the OpenSSL or SSLeay licenses, the copyright holder
* grants you additional permission to convey the resulting work.
* Corresponding Source for a non-source form of such a combination
* shall include the source code for the parts of OpenSSL used as well
* as that of the covered work.
*/
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#ifdef WINDOWS
#include <ws2tcpip.h>
#include <io.h>
#include "win_func.h"
#else // if WINDOWS
#include <sys/time.h>
#include <netdb.h>
#include <unistd.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#endif
#include "proxy.h"
#include "proxy_common.h"
#include "proxy_upstream.h"
/**
* Look for a given group in the global group list
* Returns a pointer to the group in the list, or NULL if not found
*/
struct pr_group_list_t *find_group(uint32_t group_id, uint8_t group_inst)
{
int i;
for (i = 0; i < MAXLIST; i++) {
if ((group_list[i].group_id == group_id) &&
(group_list[i].group_inst == group_inst)) {
return &group_list[i];
}
}
return NULL;
}
/**
* Look for a given client in the group's client list
* Returns the client's index in the list, or -1 if not found
*/
int find_client(struct pr_group_list_t *group, uint32_t id)
{
int i;
for (i = 0; i < group->destcount; i++) {
if (group->destinfo[i].id == id) {
return i;
}
}
return -1;
}
/**
* Checks to see if the multicast address used for the given group list member
* is also being used by either another member or the public address list
*/
int other_mcast_users(struct pr_group_list_t *group)
{
int i;
for (i = 0; i < pub_multi_count; i++) {
if (addr_equal(&group->privatemcast, &pub_multi[i])) {
return 1;
}
}
for (i = 0; i < MAXLIST; i++) {
if ((&group_list[i] != group) && (group_list[i].group_id != 0) &&
(addr_equal(&group->privatemcast,
&group_list[i].privatemcast))) {
return 1;
}
}
return 0;
}
/**
* Clean up a group list entry. Free malloc'ed structures, drop the
* multicast group (if no one else is using it) and free the slot.
*/
void group_cleanup(struct pr_group_list_t *group)
{
int i;
for (i = 0; i < MAX_PEND; i++) {
free(group->pending[i].naklist);
}
if (!addr_blank(&group->privatemcast) && (proxy_type != CLIENT_PROXY) &&
!other_mcast_users(group) && group->multi_join) {
multicast_leave(listener, group->group_id, &group->privatemcast,
m_interface, interface_count, server_fp, server_fp_count);
}
if (group->server_pubkey.key) {
if ((group->keyextype == KEYEX_RSA) ||
(group->keyextype == KEYEX_ECDH_RSA)) {
free_RSA_key(group->server_pubkey.rsa);
} else {
free_EC_key(group->server_pubkey.ec);
}
if ((group->keyextype == KEYEX_ECDH_RSA) ||
(group->keyextype == KEYEX_ECDH_ECDSA)) {
free_EC_key(group->server_dhkey.ec);
free_EC_key(group->proxy_dhkey.ec);
}
}
for (i = 0; i < group->destcount; i++) {
if (group->destinfo[i].pubkey.key) {
if ((group->keyextype == KEYEX_RSA) ||
(group->keyextype == KEYEX_ECDH_RSA)) {
free_RSA_key(group->destinfo[i].pubkey.rsa);
} else {
free_EC_key(group->destinfo[i].pubkey.ec);
}
if ((group->keyextype == KEYEX_ECDH_RSA) ||
(group->keyextype == KEYEX_ECDH_ECDSA)) {
free_EC_key(group->destinfo[i].dhkey.ec);
}
}
}
memset(group, 0, sizeof(struct pr_group_list_t));
}
/**
* Initializes the uftp header of an outgoing packet
*/
void set_uftp_header(struct uftp_h *header, int func,
struct pr_group_list_t *group)
{
header->version = group->version;
header->func = func;
header->group_id = htonl(group->group_id);
header->group_inst = group->group_inst;
header->src_id = uid;
switch (func) {
case REGISTER:
case KEYINFO_ACK:
case FILEINFO_ACK:
case STATUS:
case COMPLETE:
header->seq = htons(group->send_seq_up++);
break;
case KEYINFO:
header->seq = 0;
header->src_id = group->src_id;
header->grtt = quantize_grtt(group->grtt);
header->gsize = quantize_gsize(group->gsize);
break;
}
// ABORTs will set seq and src_id themselves depending on the direction
}
/**
* Sets the timeout time for a given group list member
*/
void set_timeout(struct pr_group_list_t *group, int pending_reset, int rescale)
{
int pending, i;
if (group->phase == PR_PHASE_READY) {
if (!rescale) {
gettimeofday(&group->start_phase_timeout_time, NULL);
}
group->phase_timeout_time = group->start_phase_timeout_time;
add_timeval_d(&group->phase_timeout_time, 2 * group->grtt);
}
glog5(group, "set timeout: pending_reset=%d", pending_reset);
for (pending = 0, i = 0; (i < MAX_PEND) && !pending; i++) {
if (group->pending[i].msg != 0) {
glog5(group, "set timeout: found pending %s",
func_name(group->pending[i].msg));
pending = group->pending[i].msg;
}
}
if (pending) {
if (pending_reset) {
if (!rescale) {
gettimeofday(&group->start_timeout_time, NULL);
}
group->timeout_time = group->start_timeout_time;
add_timeval_d(&group->timeout_time, 1 * group->grtt);
}
} else {
if (!rescale) {
gettimeofday(&group->start_timeout_time, NULL);
}
group->timeout_time = group->start_timeout_time;
if (group->robust * group->grtt < 1.0) {
add_timeval_d(&group->timeout_time, 1.0);
} else {
add_timeval_d(&group->timeout_time, group->robust * group->grtt);
}
}
}
/**
* Returns the maximum number of clients that can be listed in a given message
*/
int max_msg_dest(struct pr_group_list_t *group, int func, int hlen)
{
switch (func) {
case REGISTER:
return (group->blocksize / sizeof(uint32_t));
case KEYINFO:
return (group->blocksize / sizeof(struct destkey));
case FILEINFO_ACK:
return (group->blocksize / sizeof(uint32_t));
case COMPLETE:
return (group->blocksize / sizeof(uint32_t));
default:
return 0;
}
}
/**
* Sends a pending aggregate message for a given group and message
*/
void send_pending(struct pr_group_list_t *group, int pendidx)
{
switch (group->pending[pendidx].msg) {
case REGISTER:
send_register(group, pendidx);
break;
case FILEINFO_ACK:
send_fileinfo_ack(group, pendidx);
break;
case STATUS:
send_status(group, pendidx);
break;
case COMPLETE:
send_complete(group, pendidx);
break;
default:
glog1(group, "Tried to send pending on invalid type %s",
func_name(group->pending[pendidx].msg));
return;
}
if ((group->pending[pendidx].count <= 0) ||
(group->pending[pendidx].msg == STATUS)) {
// Finish the cleanup we started in load_pending
// Always do this for a STATUS, since we don't have a pending list
free(group->pending[pendidx].naklist);
memset(&group->pending[pendidx], 0, sizeof(struct pr_pending_info_t));
}
}
/**
* Sends all pending aggregate message for a given group
*/
void send_all_pending(struct pr_group_list_t *group)
{
int i;
for (i = 0; i < MAX_PEND; i++) {
if (group->pending[i].msg != 0) {
send_pending(group, i);
}
}
}
/**
* Add the NAKs in the given STATUS message to the list of pending NAKs
*/
void add_naks_to_pending(struct pr_group_list_t *group, int pendidx,
const unsigned char *message)
{
const unsigned char *naks;
unsigned i;
naks = message + sizeof(struct status_h);
for (i = 0; i < group->blocksize; i++) {
group->pending[pendidx].naklist[i] |= naks[i];
}
}
/**
* Puts the given message on the pending message list. If it doesn't match
* any pending message and there are no open slots, first send what's pending.
* If the pending list is full after adding the given message, then send.
*/
void check_pending(struct pr_group_list_t *group, int hostidx,
const unsigned char *message)
{
const struct fileinfoack_h *fileinfoack;
const struct status_h *status;
const struct complete_h *complete;
const uint8_t *func;
struct pr_pending_info_t *pending;
int match, pendidx, hlen;
func = message;
fileinfoack = (const struct fileinfoack_h *)message;
status = (const struct status_h *)message;
complete = (const struct complete_h *)message;
glog3(group, "check_timeout: looking for pending %s", func_name(*func));
for (pendidx = 0; pendidx < MAX_PEND; pendidx++) {
pending = &group->pending[pendidx];
if (group->pending[pendidx].msg == 0) {
glog3(group, "check_timeout: found empty slot %d", pendidx);
match = 1;
break;
}
match = (*func == pending->msg);
switch (*func) {
case REGISTER:
// REGISTER always matches itself
break;
case FILEINFO_ACK:
match = match && (ntohs(fileinfoack->file_id) == pending->file_id);
break;
case STATUS:
match = match && ((ntohs(status->file_id) == pending->file_id) &&
(ntohs(status->section) == pending->section));
break;
case COMPLETE:
match = match && ((ntohs(complete->file_id) == pending->file_id) &&
(complete->status == pending->comp_status));
break;
default:
glog1(group, "Tried to check pending on invalid type %s",
func_name(*func));
return;
}
if (match) {
break;
}
}
if (!match) {
send_all_pending(group);
pendidx = 0;
pending = &group->pending[pendidx];
}
glog3(group, "check_timeout: found match at slot %d", pendidx);
pending->msg = *func;
if (group->destinfo[hostidx].pending != pendidx) {
group->destinfo[hostidx].pending = pendidx;
pending->count++;
}
switch (*func) {
case REGISTER:
hlen = sizeof(struct register_h);
if (pending->count == 1) {
gettimeofday(&pending->rx_tstamp, NULL);
pending->tstamp = group->destinfo[hostidx].regtime;
glog3(group, "send time = %d.%06d",
pending->tstamp.tv_sec, pending->tstamp.tv_usec);
glog3(group, "rx time = %d.%06d",
pending->rx_tstamp.tv_sec, pending->rx_tstamp.tv_usec);
}
break;
case FILEINFO_ACK:
hlen = sizeof(struct fileinfoack_h);
if (pending->count == 1) {
pending->partial = 1;
gettimeofday(&pending->rx_tstamp, NULL);
pending->tstamp.tv_sec = ntohl(fileinfoack->tstamp_sec);
pending->tstamp.tv_usec = ntohl(fileinfoack->tstamp_usec);
glog3(group, "send time = %d.%06d",
pending->tstamp.tv_sec, pending->tstamp.tv_usec);
glog3(group, "rx time = %d.%06d",
pending->rx_tstamp.tv_sec, pending->rx_tstamp.tv_usec);
}
pending->file_id = ntohs(fileinfoack->file_id);
pending->partial = pending->partial &&
((fileinfoack->flags & FLAG_PARTIAL) != 0);
break;
case STATUS:
hlen = sizeof(struct status_h);
pending->file_id = ntohs(status->file_id);
pending->section = ntohs(status->section);
if (!pending->naklist) {
pending->naklist = safe_calloc(group->blocksize, 1);
}
add_naks_to_pending(group, pendidx, message);
break;
case COMPLETE:
hlen = sizeof(struct complete_h);
pending->file_id = ntohs(complete->file_id);
pending->comp_status = complete->status;
break;
}
if ((*func != STATUS) &&
(pending->count == max_msg_dest(group, *func, hlen))) {
send_pending(group, pendidx);
} else {
int total_pending, i;
glog3(group, "check_timeout: getting pending count for %s",
func_name(*func));
for (total_pending = 0, i = 0; i < MAX_PEND; i++) {
glog3(group, "check_timeout: adding %d pending for %d",
group->pending[i].count, i);
total_pending += group->pending[i].count;
}
if (total_pending == 1) {
set_timeout(group, 1, 0);
}
}
}
/**
* Check for any client that hasn't fully registered.
* If the abort parameter is set, send an ABORT to the server and client.
* Returns 1 if any aren't fully registered, 0 if all are registered.
*/
int check_unfinished_clients(struct pr_group_list_t *group, int abort_session)
{
int hostidx, found;
struct pr_destinfo_t *dest;
if (group->keytype == KEY_NONE) {
return 0;
}
found = 0;
for (hostidx = 0; hostidx < group->destcount; hostidx++) {
dest = &group->destinfo[hostidx];
if ((group->group_id != 0) &&
(dest->state != PR_CLIENT_READY)) {
if (abort_session) {
send_downstream_abort(group, dest->id,
"Client not fully registered at proxy", 0);
send_upstream_abort(group, dest->id,
"Client not fully registered at proxy");
}
found = 1;
}
}
return found;
}
/**
* Load a message body with the list of pending clients
*/
int load_pending(struct pr_group_list_t *group, int pendidx, int func,
uint32_t *addrlist, int listlen)
{
int hostidx, cnt;
struct pr_destinfo_t *dest;
for (cnt = 0, hostidx = 0;
(hostidx < group->destcount) && (cnt < listlen); hostidx++) {
dest = &group->destinfo[hostidx];
if (dest->pending == pendidx) {
addrlist[cnt++] = dest->id;
dest->pending = -1;
group->pending[pendidx].count--;
}
}
if (group->pending[pendidx].count <= 0) {
// Don't zero out the whole pending struct.
// We need to clear the message now to set timeouts properly but
// we still use the other fields just before sending the message.
// The full cleanup is done in send_pending
group->pending[pendidx].count = 0;
group->pending[pendidx].msg = 0;
}
return cnt;
}
/**
* Forward a message unmodified to the next hop, resigning if necessary.
*/
void forward_message(struct pr_group_list_t *group,
const union sockaddr_u *src,
unsigned char *packet, int packetlen)
{
struct uftp_h *header;
struct encrypted_h *encrypted;
struct announce_h *announce;
struct enc_info_he *encinfo;
union sockaddr_u dest;
unsigned int meslen, siglen;
int hostidx, rval, iplen, resign;
char destname[INET6_ADDRSTRLEN], destport[PORTNAME_LEN];
uint8_t *sig, *sigcopy;
union key_t key;
header = (struct uftp_h *)packet;
meslen = (unsigned int)packetlen;
memset(&dest, 0, sizeof(dest));
if (!memcmp(src, &group->up_addr, sizeof(*src))) {
if (proxy_type == RESPONSE_PROXY) {
// Response proxy, no downstream forwarding
set_timeout(group, 0, 0);
return;
} else if (proxy_type == SERVER_PROXY) {
dest = down_addr;
} else {
if (header->func == ANNOUNCE) {
dest = group->publicmcast;
} else {
dest = group->privatemcast;
}
key = group->server_pubkey;
}
} else {
dest = group->up_addr;
if (proxy_type != SERVER_PROXY) {
hostidx = find_client(group, header->src_id);
if (hostidx == -1) {
glog1(group, "Couldn't find receiver in list");
return;
}
key = group->destinfo[hostidx].pubkey;
}
}
// If we're using KEYEX signatures, or sending an ANNOUNCE with ECDH,
// verify the signature and resign
resign = 0;
if ((proxy_type != SERVER_PROXY) && (header->func == ENCRYPTED) &&
(group->sigtype == SIG_KEYEX)) {
encrypted = (struct encrypted_h *)(packet + sizeof(struct uftp_h));
sig = (uint8_t *)encrypted + sizeof(struct encrypted_h);
siglen = ntohs(encrypted->sig_len);
resign = 1;
} else if ((proxy_type != SERVER_PROXY) && (header->func == ANNOUNCE) &&
((group->keyextype == KEYEX_ECDH_RSA) ||
(group->keyextype == KEYEX_ECDH_ECDSA))) {
announce = (struct announce_h *)(packet + sizeof(struct uftp_h));
iplen = ((announce->flags & FLAG_IPV6) != 0) ? 16 : 4;
encinfo = (struct enc_info_he *) ((uint8_t *)announce +
sizeof(struct announce_h) + iplen + iplen);
sig = (uint8_t *)encinfo + sizeof(struct enc_info_he) +
ntohs(encinfo->keylen) + ntohs(encinfo->dhlen);
siglen = ntohs(encinfo->siglen);
resign = 1;
}
if (resign) {
sigcopy = safe_calloc(siglen, 1);
memcpy(sigcopy, sig, siglen);
memset(sig, 0, siglen);
if ((group->keyextype == KEYEX_RSA) ||
(group->keyextype == KEYEX_ECDH_RSA)) {
if (header->func == ENCRYPTED) {
if (!verify_RSA_sig(key.rsa, group->hashtype, packet,
meslen, sigcopy, siglen)) {
glog1(group, "Signature verification failed");
free(sigcopy);
return;
}
}
if (!create_RSA_sig(group->proxy_privkey.rsa, group->hashtype,
packet, meslen, sigcopy, &siglen)) {
glog0(group, "Signature creation failed");
free(sigcopy);
return;
}
} else {
if (header->func == ENCRYPTED) {
if (!verify_ECDSA_sig(key.ec, group->hashtype, packet,
meslen, sigcopy, siglen)) {
glog1(group, "Signature verification failed");
free(sigcopy);
return;
}
}
if (!create_ECDSA_sig(group->proxy_privkey.ec, group->hashtype,
packet, meslen, sigcopy, &siglen)) {
glog0(group, "Signature creation failed");
free(sigcopy);
return;
}
}
memcpy(sig, sigcopy, siglen);
free(sigcopy);
}
if (nb_sendto(listener, packet, meslen, 0, (struct sockaddr *)&dest,
family_len(dest)) == SOCKET_ERROR) {
gsockerror(group, "Error forwarding message");
if ((rval = getnameinfo((struct sockaddr *)&dest, family_len(dest),
destname, sizeof(destname), destport, sizeof(destport),
NI_NUMERICHOST | NI_NUMERICSERV)) != 0) {
glog1(group, "getnameinfo failed: %s", gai_strerror(rval));
}
glog2(group, "Dest: %s:%s", destname, destport);
}
set_timeout(group, 0, 0);
}
/**
* Process an HB_REQ message
*/
void handle_hb_request(const union sockaddr_u *src,
unsigned char *packet, unsigned packetlen)
{
struct hb_req_h *hbreq;
unsigned char *keyblob, *sig;
union key_t key;
unsigned char fingerprint[HMAC_LEN];
unsigned int fplen, bloblen, siglen;
char destname[INET6_ADDRSTRLEN], destport[PORTNAME_LEN];
int resp, rval;
hbreq = (struct hb_req_h *)(packet + sizeof(struct uftp_h));
if ((rval = getnameinfo((const struct sockaddr *)src, family_len(*src),
destname, sizeof(destname), destport, sizeof(destport),
NI_NUMERICHOST | NI_NUMERICSERV)) != 0) {
log1(0, 0, 0, "getnameinfo failed: %s", gai_strerror(rval));
}
if ((packetlen < sizeof(struct uftp_h) + (hbreq->hlen * 4)) ||
((hbreq->hlen * 4) < sizeof(struct hb_req_h))) {
log1(0,0,0, "Rejecting HB_REQ from %s: invalid message size", destname);
return;
}
log2(0, 0, 0, "Received HB_REQ from %s", destname);
if ((proxy_type == SERVER_PROXY) && have_down_fingerprint) {
if (addr_equal(&down_addr, src)) {
resp = HB_AUTH_OK;
} else if (down_nonce != ntohl(hbreq->nonce)) {
resp = HB_AUTH_CHALLENGE;
} else {
keyblob = (unsigned char *)hbreq + sizeof(struct hb_req_h);
bloblen = ntohs(hbreq->bloblen);
sig = keyblob + bloblen;
siglen = ntohs(hbreq->siglen);
// First check key fingerprint, then check signature
if (keyblob[0] == KEYBLOB_RSA) {
if (!import_RSA_key(&key.rsa, keyblob, bloblen)) {
log1(0, 0, 0, "Failed to import public key from HB_REQ");
resp = HB_AUTH_FAILED;
goto end;
}
hash(HASH_SHA1, keyblob, bloblen, fingerprint, &fplen);
if (memcmp(down_fingerprint, fingerprint, fplen)) {
log1(0, 0, 0, "Failed to verify HB_REQ fingerprint");
resp = HB_AUTH_FAILED;
goto end;
}
if (!verify_RSA_sig(key.rsa, HASH_SHA1,
(unsigned char *)&hbreq->nonce,
sizeof(hbreq->nonce), sig, siglen)) {
log1(0, 0, 0, "Failed to verify HB_REQ signature");
resp = HB_AUTH_FAILED;
goto end;
}
} else {
if (!import_EC_key(&key.ec, keyblob, bloblen, 0)) {
log1(0, 0, 0, "Failed to import public key from HB_REQ");
resp = HB_AUTH_FAILED;
goto end;
}
hash(HASH_SHA1, keyblob, bloblen, fingerprint, &fplen);
if (memcmp(down_fingerprint, fingerprint, fplen)) {
log1(0, 0, 0, "Failed to verify HB_REQ fingerprint");
resp = HB_AUTH_FAILED;
goto end;
}
if (!verify_ECDSA_sig(key.ec, HASH_SHA1,
(unsigned char *)&hbreq->nonce,
sizeof(hbreq->nonce), sig, siglen)) {
log1(0, 0, 0, "Failed to verify HB_REQ signature");
resp = HB_AUTH_FAILED;
goto end;
}
}
down_addr = *src;
log2(0, 0, 0, "Using %s:%s as downstream address:port",
destname, destport);
down_nonce = rand32();
resp = HB_AUTH_OK;
}
} else {
resp = HB_AUTH_OK;
}
end:
send_hb_response(src, resp);
}
/**
* Process an KEY_REQ message
*/
void handle_key_req(const union sockaddr_u *src,
const unsigned char *packet, unsigned packetlen)
{
const struct key_req_h *keyreq;
struct timeval current_timestamp;
char destname[INET6_ADDRSTRLEN];
int rval;
keyreq = (const struct key_req_h *)(packet + sizeof(struct uftp_h));
if ((rval = getnameinfo((const struct sockaddr *)src, family_len(*src),
destname, sizeof(destname), NULL, 0, NI_NUMERICHOST)) != 0) {
log1(0, 0, 0, "getnameinfo failed: %s", gai_strerror(rval));
}
if ((packetlen < sizeof(struct uftp_h) + (keyreq->hlen * 4U)) ||
((keyreq->hlen * 4U) < sizeof(struct key_req_h))) {
log1(0,0,0,"Rejecting KEY_REQ from %s: invalid message size", destname);
return;
}
log2(0, 0, 0, "Received KEY_REQ from %s", destname);
gettimeofday(¤t_timestamp, NULL);
if (diff_sec(current_timestamp, last_key_req) > KEY_REQ_LIMIT) {
send_proxy_key();
}
}
/**
* Sends an HB_RESP in response to an HB_REQ
*/
void send_hb_response(const union sockaddr_u *src, int response)
{
unsigned char *packet;
struct uftp_h *header;
struct hb_resp_h *hbresp;
char destname[INET6_ADDRSTRLEN], destport[PORTNAME_LEN];
int meslen, rval;
packet = safe_calloc(sizeof(struct uftp_h) + sizeof(struct hb_resp_h), 1);
header = (struct uftp_h *)packet;
hbresp = (struct hb_resp_h *)(packet + sizeof(struct uftp_h));
header->version = UFTP_VER_NUM;
header->func = HB_RESP;
header->src_id = uid;
hbresp->func = HB_RESP;
hbresp->hlen = sizeof(struct hb_resp_h) / 4;
hbresp->authenticated = response;
if (response == HB_AUTH_CHALLENGE) {
hbresp->nonce = htonl(down_nonce);
}
meslen = sizeof(struct uftp_h) + sizeof(struct hb_resp_h);
if (nb_sendto(listener, packet, meslen, 0, (const struct sockaddr *)src,
family_len(*src)) == SOCKET_ERROR) {
sockerror(0, 0, 0, "Error sending HB_RESP");
} else {
if ((rval = getnameinfo((const struct sockaddr *)src,
family_len(*src), destname, sizeof(destname), destport,
sizeof(destport), NI_NUMERICHOST | NI_NUMERICSERV)) != 0) {
log1(0, 0, 0, "getnameinfo failed: %s", gai_strerror(rval));
}
log2(0, 0, 0, "Sent HB_RESP to %s:%s", destname, destport);
}
free(packet);
}
/**
* Sends a PROXY_KEY message to the first listed public multicast address.
*/
void send_proxy_key()
{
unsigned char *packet, *keyblob, *dhblob, *sig;
struct uftp_h *header;
struct proxy_key_h *proxykey;
uint32_t nonce;
unsigned int meslen, siglen;
uint16_t bloblen, dhlen;
char pubname[INET6_ADDRSTRLEN];
int rval;
packet = safe_calloc(sizeof(struct uftp_h) + sizeof(struct hb_req_h) +
(PUBKEY_LEN * 3) , 1);
header = (struct uftp_h *)packet;
proxykey = (struct proxy_key_h *)(packet + sizeof(struct uftp_h));
keyblob = (unsigned char *)proxykey + sizeof(struct proxy_key_h);
header->version = UFTP_VER_NUM;
header->func = PROXY_KEY;
header->src_id = uid;
proxykey->func = PROXY_KEY;
nonce = htonl(rand32());
proxykey->nonce = nonce;
if (privkey_type[0] == KEYBLOB_RSA) {
if (!export_RSA_key(privkey[0].rsa, keyblob, &bloblen)) {
log0(0, 0, 0, "Error exporting public key");
free(packet);
return;
}
} else {
if (!export_EC_key(privkey[0].ec, keyblob, &bloblen)) {
log0(0, 0, 0, "Error exporting public key");
free(packet);
return;
}
}
dhblob = keyblob + bloblen;
if (dhkey.key) {
if (!export_EC_key(dhkey.ec, dhblob, &dhlen)) {
log0(0, 0, 0, "Error exporting public key");
free(packet);
return;
}
} else {
dhlen = 0;
}
sig = dhblob + dhlen;
if (privkey_type[0] == KEYBLOB_RSA) {
if (!create_RSA_sig(privkey[0].rsa, HASH_SHA1, (unsigned char *)&nonce,
sizeof(nonce), sig, &siglen)) {
log0(0, 0, 0, "Error signing nonce");
free(packet);
return;
}
} else {
if (!create_ECDSA_sig(privkey[0].ec, HASH_SHA1, (unsigned char *)&nonce,
sizeof(nonce), sig, &siglen)) {
log0(0, 0, 0, "Error signing nonce");
free(packet);
return;
}
}
proxykey->bloblen = htons(bloblen);
proxykey->dhlen = htons(dhlen);
proxykey->siglen = htons(siglen);
proxykey->hlen = (sizeof(struct proxy_key_h) + bloblen + dhlen + siglen)/4;
meslen = sizeof(struct uftp_h) + (proxykey->hlen * 4);
if (nb_sendto(listener, packet, meslen, 0,
(struct sockaddr *)&pub_multi[0],
family_len(pub_multi[0])) == SOCKET_ERROR) {
sockerror(0, 0, 0, "Error sending PROXY_KEY");
} else {
if ((rval = getnameinfo((struct sockaddr *)&pub_multi[0],
family_len(pub_multi[0]), pubname, sizeof(pubname), NULL, 0,
NI_NUMERICHOST)) != 0) {
log1(0, 0, 0, "getnameinfo failed: %s", gai_strerror(rval));
}
log2(0, 0, 0, "Sent PROXY_KEY to %s", pubname);
}
free(packet);
}
/**
* Sends an ABORT message upstream to a server
*/
void send_upstream_abort(struct pr_group_list_t *group, uint32_t addr,
const char *message)
{
unsigned char *buf;
struct uftp_h *header;
struct abort_h *abort_hdr;
int payloadlen;
buf = safe_calloc(MAXMTU, 1);
header = (struct uftp_h *)buf;
abort_hdr = (struct abort_h *)(buf + sizeof(struct uftp_h));
set_uftp_header(header, ABORT, group);
header->seq = group->send_seq_up++;
header->src_id = uid;
abort_hdr->func = ABORT;
abort_hdr->hlen = sizeof(struct abort_h) / 4;
abort_hdr->flags = 0;
abort_hdr->host = addr;
strncpy(abort_hdr->message, message, sizeof(abort_hdr->message) - 1);
payloadlen = sizeof(struct uftp_h) + sizeof(struct abort_h);
// Proxies should never need to send an encrypted ABORT
if (nb_sendto(listener, buf, payloadlen, 0,
(struct sockaddr *)&group->up_addr,
family_len(group->up_addr)) == SOCKET_ERROR) {
gsockerror(group, "Error sending ABORT");
}
if (addr == 0) {
group_cleanup(group);
}
free(buf);
}
/**
* Sends an ABORT message downstream to clients
*/
void send_downstream_abort(struct pr_group_list_t *group, uint32_t dest_id,
const char *message, int current)
{
unsigned char *buf;
struct uftp_h *header;
struct abort_h *abort_hdr;
int payloadlen;
buf = safe_calloc(MAXMTU, 1);
header = (struct uftp_h *)buf;
abort_hdr = (struct abort_h *)(buf + sizeof(struct uftp_h));
set_uftp_header(header, ABORT, group);
header->seq = group->send_seq_down++;
header->src_id = uid;
abort_hdr->func = ABORT;
abort_hdr->hlen = sizeof(struct abort_h) / 4;
if ((dest_id == 0) && current) {
abort_hdr->flags |= FLAG_CURRENT_FILE;
}
abort_hdr->host = dest_id;
strncpy(abort_hdr->message, message, sizeof(abort_hdr->message) - 1);
payloadlen = sizeof(struct uftp_h) + sizeof(struct abort_h);
// Proxies should never need to send an encrypted ABORT
if (nb_sendto(listener, buf, payloadlen, 0,
(struct sockaddr *)&group->privatemcast,
family_len(group->privatemcast)) == SOCKET_ERROR) {
gsockerror(group, "Error sending ABORT");
}
free(buf);
}
/**
* Handles an ABORT message from a client or server
* and forwards if necessary.
*/
void handle_abort(struct pr_group_list_t *group, const union sockaddr_u *src,
const unsigned char *message, unsigned meslen,
uint32_t src_id)
{
const struct abort_h *abort_hdr;
int upstream, hostidx, current;
abort_hdr = (const struct abort_h *)message;
upstream = (addr_equal(&group->up_addr, src));
if (meslen < (abort_hdr->hlen * 4U) ||
((abort_hdr->hlen * 4U) < sizeof(struct abort_h))) {
glog1(group, "Rejecting ABORT from %s: invalid message size",
upstream ? "server" : "client");
}
if (upstream) {
if ((abort_hdr->host == 0) || abort_hdr->host == uid ) {
glog1(group, "Transfer aborted by server: %s", abort_hdr->message);
current = ((abort_hdr->flags & FLAG_CURRENT_FILE) != 0);
if (proxy_type != RESPONSE_PROXY) {
send_downstream_abort(group, 0, abort_hdr->message, current);
}
if (!current) {
group_cleanup(group);
}
} else {
if (proxy_type != RESPONSE_PROXY) {
send_downstream_abort(group, abort_hdr->host,
abort_hdr->message, 0);
}
}
} else {
if ((hostidx = find_client(group, src_id)) != -1) {