/* helper function for reading data from a client */
int client_read_bytes (client_t *client, void *buf, unsigned len)
{
int (*con_read)(struct connection_tag *handle, void *buf, size_t len) = connection_read;
int bytes;
if (len == 0)
return 0;
if (client->refbuf && client->pos < client->refbuf->len)
{
unsigned remaining = client->refbuf->len - client->pos;
if (remaining > len)
remaining = len;
memcpy (buf, client->refbuf->data + client->pos, remaining);
client->pos += remaining;
if (client->pos >= client->refbuf->len)
client_set_queue (client, NULL);
return remaining;
}
#ifdef HAVE_OPENSSL
if (client->connection.ssl)
con_read = connection_read_ssl;
#endif
bytes = con_read (&client->connection, buf, len);
if (bytes == -1 && client->connection.error)
DEBUG0 ("reading from connection has failed");
return bytes;
}
int main(int argc, char* argv[]) {
int opt;
bool vns_console = false;
char* command_file = NULL; char* pid_file = NULL;
int i, ifcount = 0; struct vnlif iflist[vnlif_maxcount];
int command_fd, command_eth = -1; FILE* pid_fd;
struct pollfd pollfds[2+2*vnlif_maxcount]; int pollres;
char buffer[MSGSIZE]; int len;
char* pktbuffer = buffer + MSGHDRSIZE;
c_base* vnsbasehdr = (c_base*)buffer;
c_hwinfo* vnshwinfo = (c_hwinfo*)buffer;
c_packet_header* vnspkthdr = (c_packet_header*)buffer;
// ---------------- parse command options ----------------
while ((opt = getopt(argc, argv, "si:c:p:")) != -1) {
switch (opt) {
case 's': vns_console = true; break;
case 'i':
if (ifcount < vnlif_maxcount) {
if (!vnlif_parse(iflist + ifcount, optarg)) die("vnlif_parse");
} else {
die("cmdline vnlif_maxcount");
}
++ifcount;
break;
case 'c': command_file = optarg; break;
case 'p': pid_file = optarg; break;
}
}
if (ifcount == 0 || command_file == NULL || pid_file == NULL) {
printf("vnlsvc: Virtual Network Lab Service\nTAP-UDP: vnlsvc -i eth0/tap0/1a:8e:22:b1:da:f1/198.51.100.1#255.255.255.0/192.0.2.1:2001/192.0.2.2:2001/ -c /tmp/command.pipe -p /tmp/vnltun.pid\nVNSconsole-UDP: vnlsvc -s -i eth0//1a:8e:22:b1:da:f1/198.51.100.1#255.255.255.0/192.0.2.1:2001/192.0.2.2:2001/ -c /tmp/command.pipe -p /tmp/vnltun.pid\n");
exit(1);
}
// ---------------- open files and sockets ----------------
command_fd = open(command_file, O_RDONLY | O_NONBLOCK);
if (command_fd < 0) die("command open");
pollfds[0].fd = 0; pollfds[0].events = vns_console ? POLLIN : 0;
pollfds[1].fd = command_fd; pollfds[1].events = POLLIN;
for (i = 0; i < ifcount; ++i) {
pollfds[2+i].fd = iflist[i].udp_fd
= udp_open(&(iflist[i].tip), &(iflist[i].rtip));
pollfds[2+i].events = POLLIN;
if (!vns_console) {
pollfds[2+ifcount+i].fd = iflist[i].tap_fd = tap_open(iflist[i].tapname);
pollfds[2+ifcount+i].events = POLLIN;
}
}
//pollfds: 0=stdin, 1=command pipe, 2..2+ifcount-1=UDP, 2+ifcount..2+2*ifcount-1=TAP
// ---------------- initialize ----------------
pid_fd = fopen(pid_file, "w");
if (pid_fd == NULL) die("pid output");
fprintf(pid_fd, "%d", getpid());
fclose(pid_fd);
srand(time(NULL));
if (vns_console) {
con_init();
vns_wAuthReq(buffer); con_write(buffer);
}
// ---------------- main poll loop ----------------
while (1) {
pollres = poll(pollfds, 2+(vns_console?1:2)*ifcount, -1);
if (pollres == -1) die("poll");
else if (pollres == 0) { perror("poll timeout"); continue; }
/*
for (i = 0; i < 2+(vns_console?1:2)*ifcount; ++i) {
if (pollfds[i].revents & (POLLERR | POLLHUP | POLLNVAL)) {
FILE* dbglog = fopen("/tmp/vnlsvc.debug.log","a");
fprintf(dbglog,"%d %d %d %x\n",time(NULL),getpid(),i,pollfds[i].revents);
fclose(dbglog);
}
}
*/
// ---------------- VNS protocol, console to UDP ----------------
if (vns_console && (pollfds[0].revents & POLLIN)) {
if (con_read(buffer)) {
switch (vns_getType(buffer)) {
case VNS_AUTH_REPLY:
vns_wAuthStatus(buffer); con_write(buffer);
break;
case VNSOPEN:
iflist_hwinfo(vnshwinfo, iflist, ifcount);
con_write(buffer);
break;
case VNSPACKET:
i = iflist_find(iflist, ifcount, vnspkthdr->mInterfaceName);
if (i < 0) break;
len = ntohl(vnspkthdr->mLen) - sizeof(c_packet_header);
if (lossy_filter(iflist[i].lossy)) {
udp_write(iflist[i].udp_fd, pktbuffer, len, &(iflist[i].rtip));
}
break;
}
}
}
// ---------------- console error ----------------
if (vns_console && (pollfds[0].revents & (POLLERR | POLLHUP))) {
die("console error");
}
// ---------------- setlossy command ----------------
if (pollfds[1].revents & POLLIN) {
if (command_eth < 0 && 1 == read(command_fd, buffer, 1)) {
command_eth = buffer[0];
}
if (1 == read(command_fd, buffer, 1) && command_eth < ifcount) {
iflist[command_eth].lossy = buffer[0];
}
}
if (pollfds[1].revents & POLLHUP) {
command_eth = -1;
close(command_fd);
pollfds[1].fd = command_fd = open(command_file, O_RDONLY | O_NONBLOCK);
if (command_fd < 0) die("command reopen");
}
for (i = 0; i < ifcount; ++i) {
// ---------------- UDP to console/TAP ----------------
if (pollfds[2+i].revents & POLLIN) {
len = udp_read(iflist[i].udp_fd, pktbuffer, &(iflist[i].rtip));
if (len > 0) {
if (vns_console) {
vns_wPacketHdr(buffer, len, iflist[i].ifname);
con_write(buffer);
} else {
tap_write(iflist[i].tap_fd, pktbuffer, len);
}
}
}
// ---------------- UDP error ----------------
if (pollfds[2+i].revents & POLLERR) {
int sockerror; socklen_t socklen = sizeof(int);
getsockopt(iflist[i].udp_fd, SOL_SOCKET, SO_ERROR, &sockerror, &socklen);
}
// ---------------- TAP to UDP ----------------
if (!vns_console && (pollfds[2+ifcount+i].revents & POLLIN)) {
len = tap_read(iflist[i].tap_fd, pktbuffer);
if (len > 0 && lossy_filter(iflist[i].lossy)) {
udp_write(iflist[i].udp_fd, pktbuffer, len, &(iflist[i].rtip));
}
}
}
}
}
/**
* @brief Extract the contents of a literal string and advance the position of the parser stream.
* @note This function expects as input a string beginning with '{' and followed by a numerical string, an optional '+', and a closing '}'.
After reading in the numerical size parameter, it then attempts to read in that many bytes of input from the network stream.
* @param con the client IMAP connection passing the literal string as input to the server.
* @param output the address of a managed string that will receive a copy of the literal string's contents on success, or NULL on failure or if it is zero length.
* @param start the address of a pointer to the start of the buffer to be parsed (beginning with '{'), that will also be updated to
* point to the next argument in the sequence on success.
* @param length a pointer to a size_t variable that contains the length of the string to be parsed, and that will be updated to reflect
* the length of the remainder of the input string that follows the parsed literal string.
* @return -1 on general or parse error or if an enclosing pair of double quotes was not found, or 1 if the supplied quoted string was valid.
*/
int_t imap_parse_literal(connection_t *con, stringer_t **output, chr_t **start, size_t *length) {
chr_t *holder;
int_t plus = 0;
stringer_t *result;
size_t characters, left;
ssize_t nread;
uint64_t literal, number;
// Get setup.
holder = *start;
left = *length;
*output = NULL;
// Skip the opening bracket.
if (*holder != '{' || !left) {
return -1;
}
else {
holder++;
left--;
}
// Advance until we have a break character.
while (left && *holder >= '0' && *holder <= '9') {
holder++;
left--;
}
// Store the length.
characters = holder - *start - 1;
if (left && *holder == '+') {
plus = 1;
holder++;
left--;
}
if (*holder != '}' || !characters) {
return -1;
}
// Convert to a number. Make sure the number is positive.
if (!uint64_conv_bl(*start + 1, characters, &number)) {
return -1;
}
literal = (size_t)number;
// If the number is larger than 128 megabytes, then reject it.
if (!plus && number > 134217728) {
return -1;
}
// They client is already transmitting, so read the entire file, then reject it.
else if (number > 134217728) {
while (number > 0) {
// Read the data.
if ((nread = con_read(con)) <= 0) {
log_pedantic("The connection was dropped while reading the literal.");
return -1;
}
// Deal with signedness problem.
characters = nread;
if (number > (uint64_t)characters) {
number -= characters;
}
else {
// If we have any extra characters in the buffer, move them to the beginning.
if ((uint64_t)characters > number) {
mm_move(st_char_get(con->network.buffer), st_char_get(con->network.buffer) + number, characters - number);
st_length_set(con->network.buffer, characters - number);
con->network.line = line_pl_st(con->network.buffer, 0);
}
else {
st_length_set(con->network.buffer, 0);
con->network.line = pl_null();
}
// Make sure we have a full line.
if (pl_empty(con->network.line) && con_read_line(con, true) <= 0) {
log_pedantic("The connection was dropped while reading the literal.");
return -1;
}
number = 0;
}
}
return -1;
}
// If this is not a plus literal, output the proceed statement.
if (!plus) {
con_write_bl(con, "+ GO\r\n", 6);
}
// Handle the special case of a zero length literal.
if (literal == 0) {
// Read the next line.
if (con_read_line(con, true) <= 0) {
log_pedantic("The connection was dropped while reading the literal.");
return -1;
}
*start = st_char_get(con->network.buffer);
*length = pl_length_get(con->network.line);
// There should be a space before the next argument.
if (*length && **start == ' ') {
(*start)++;
(*length)--;
}
return 1;
}
// Allocate a stringer for the buffer.
if (!(result = st_alloc(literal))) {
log_pedantic("Unable to allocate a buffer of %lu bytes for the literal argument.", literal);
return -1;
}
// So we know how many more characters to read.
left = literal;
// Where we put the data.
holder = st_char_get(result);
// Keep looping until we run out of data.
while (left) {
// Read the data.
if ((nread = con_read(con)) <= 0) {
log_pedantic("The connection was dropped while reading the literal.");
st_free(result);
return -1;
}
characters = nread;
// If we have a buffer, copy the data into the buffer.
mm_copy(holder, st_char_get(con->network.buffer), (left > characters) ? characters : left);
if (left > characters) {
holder += characters;
left -= characters;
}
else {
st_length_set(result, literal);
// If we have any extra characters in the buffer, move them to the beginning.
if (characters > left) {
mm_move(st_char_get(con->network.buffer), st_char_get(con->network.buffer) + left, characters - left);
st_length_set(con->network.buffer, characters - left);
con->network.line = line_pl_st(con->network.buffer, 0);
}
else {
st_length_set(con->network.buffer, 0);
con->network.line = pl_null();
}
// Make sure we have a full line.
if (pl_empty(con->network.line) && con_read_line(con, true) <= 0) {
log_pedantic("The connection was dropped while reading the literal.");
st_free(result);
return -1;
}
left = 0;
}
}
*start = st_char_get(con->network.buffer);
*length = pl_length_get(con->network.line);
// There should be a space before the next argument.
if (*length && **start == ' ') {
(*start)++;
(*length)--;
}
if (result != NULL) {
*output = result;
}
else {
return -1;
}
return 1;
}
