/*
* Call this when proxy negotiation is complete, so that this
* socket can begin working normally.
*/
void proxy_activate(Proxy_Socket p)
{
void *data;
int len;
long output_before, output_after;
p->state = PROXY_STATE_ACTIVE;
/* we want to ignore new receive events until we have sent
* all of our buffered receive data.
*/
sk_set_frozen(p->sub_socket, 1);
/* how many bytes of output have we buffered? */
output_before = bufchain_size(&p->pending_oob_output_data) +
bufchain_size(&p->pending_output_data);
/* and keep track of how many bytes do not get sent. */
output_after = 0;
/* send buffered OOB writes */
while (bufchain_size(&p->pending_oob_output_data) > 0) {
bufchain_prefix(&p->pending_oob_output_data, &data, &len);
output_after += sk_write_oob(p->sub_socket, data, len);
bufchain_consume(&p->pending_oob_output_data, len);
}
/* send buffered normal writes */
while (bufchain_size(&p->pending_output_data) > 0) {
bufchain_prefix(&p->pending_output_data, &data, &len);
output_after += sk_write(p->sub_socket, data, len);
bufchain_consume(&p->pending_output_data, len);
}
/* if we managed to send any data, let the higher levels know. */
if (output_after < output_before)
plug_sent(p->plug, output_after);
/* if we were asked to flush the output during
* the proxy negotiation process, do so now.
*/
if (p->pending_flush)
sk_flush(p->sub_socket);
/* if we have a pending EOF to send, send it */
if (p->pending_eof)
sk_write_eof(p->sub_socket);
/* if the backend wanted the socket unfrozen, try to unfreeze.
* our set_frozen handler will flush buffered receive data before
* unfreezing the actual underlying socket.
*/
if (!p->freeze)
sk_set_frozen((Socket)p, 0);
}
int try_output(int is_stderr)
{
bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
int fd = (is_stderr ? STDERR_FILENO : STDOUT_FILENO);
void *senddata;
int sendlen, ret;
if (bufchain_size(chain) > 0) {
int prev_nonblock = nonblock(fd);
do {
bufchain_prefix(chain, &senddata, &sendlen);
ret = write(fd, senddata, sendlen);
if (ret > 0)
bufchain_consume(chain, ret);
} while (ret == sendlen && bufchain_size(chain) != 0);
if (!prev_nonblock)
no_nonblock(fd);
if (ret < 0 && errno != EAGAIN) {
perror(is_stderr ? "stderr: write" : "stdout: write");
exit(1);
}
}
if (outgoingeof == EOF_PENDING && bufchain_size(&stdout_data) == 0) {
close(STDOUT_FILENO);
outgoingeof = EOF_SENT;
}
return bufchain_size(&stdout_data) + bufchain_size(&stderr_data);
}
static int localproxy_try_send(Local_Proxy_Socket ps)
{
int sent = 0;
while (bufchain_size(&ps->pending_output_data) > 0) {
void *data;
int len, ret;
bufchain_prefix(&ps->pending_output_data, &data, &len);
ret = write(ps->to_cmd, data, len);
if (ret < 0 && errno != EWOULDBLOCK) {
/* We're inside the Unix frontend here, so we know
* that the frontend handle is unnecessary. */
logevent(NULL, strerror(errno));
fatalbox("%s", strerror(errno));
} else if (ret <= 0) {
break;
} else {
bufchain_consume(&ps->pending_output_data, ret);
sent += ret;
}
}
if (bufchain_size(&ps->pending_output_data) == 0)
uxsel_del(ps->to_cmd);
else
uxsel_set(ps->to_cmd, 2, localproxy_select_result);
return sent;
}
int try_output(int is_stderr)
{
bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
int fd = (is_stderr ? STDERR_FILENO : STDOUT_FILENO);
void *senddata;
int sendlen, ret, fl;
if (bufchain_size(chain) == 0)
return bufchain_size(&stdout_data) + bufchain_size(&stderr_data);
fl = fcntl(fd, F_GETFL);
if (fl != -1 && !(fl & O_NONBLOCK))
fcntl(fd, F_SETFL, fl | O_NONBLOCK);
do {
bufchain_prefix(chain, &senddata, &sendlen);
ret = write(fd, senddata, sendlen);
if (ret > 0)
bufchain_consume(chain, ret);
} while (ret == sendlen && bufchain_size(chain) != 0);
if (fl != -1 && !(fl & O_NONBLOCK))
fcntl(fd, F_SETFL, fl);
if (ret < 0 && errno != EAGAIN) {
perror(is_stderr ? "stderr: write" : "stdout: write");
exit(1);
}
return bufchain_size(&stdout_data) + bufchain_size(&stderr_data);
}
static void serial_try_write(Serial serial)
{
void *data;
int len, ret;
assert(serial->fd >= 0);
while (bufchain_size(&serial->output_data) > 0) {
bufchain_prefix(&serial->output_data, &data, &len);
ret = write(serial->fd, data, len);
if (ret < 0 && (errno == EWOULDBLOCK)) {
/*
* We've sent all we can for the moment.
*/
break;
}
if (ret < 0) {
perror("write serial port");
exit(1);
}
bufchain_consume(&serial->output_data, ret);
}
serial_uxsel_setup(serial);
}
static void logfopen_callback(void *handle, int mode)
{
struct LogContext *ctx = (struct LogContext *)handle;
char buf[256], *event;
struct tm tm;
const char *fmode;
if (mode == 0) {
ctx->state = L_ERROR; /* disable logging */
} else {
fmode = (mode == 1 ? "ab" : "wb");
ctx->lgfp = f_open(&ctx->currlogfilename, fmode, FALSE);
if (ctx->lgfp)
ctx->state = L_OPEN;
else
ctx->state = L_ERROR;
}
if (ctx->state == L_OPEN) {
/* Write header line into log file. */
tm = ltime();
strftime(buf, 24, "%Y.%m.%d %H:%M:%S", &tm);
logprintf(ctx, "=~=~=~=~=~=~=~=~=~=~=~= PuTTY log %s"
" =~=~=~=~=~=~=~=~=~=~=~=\r\n", buf);
}
event = dupprintf("%s session log (%s mode) to file: %s",
ctx->state == L_ERROR ?
(mode == 0 ? "Disabled writing" : "Error writing") :
(mode == 1 ? "Appending" : "Writing new"),
(ctx->cfg.logtype == LGTYP_ASCII ? "ASCII" :
ctx->cfg.logtype == LGTYP_DEBUG ? "raw" :
ctx->cfg.logtype == LGTYP_PACKETS ? "SSH packets" :
ctx->cfg.logtype == LGTYP_SSHRAW ? "SSH raw data" :
"unknown"),
filename_to_str(&ctx->currlogfilename));
logevent(ctx->frontend, event);
sfree(event);
/*
* Having either succeeded or failed in opening the log file,
* we should write any queued data out.
*/
assert(ctx->state != L_OPENING); /* make _sure_ it won't be requeued */
while (bufchain_size(&ctx->queue)) {
void *data;
int len;
bufchain_prefix(&ctx->queue, &data, &len);
logwrite(ctx, data, len);
bufchain_consume(&ctx->queue, len);
}
}
static void handle_try_output(struct handle_output *ctx)
{
void *senddata;
int sendlen;
if (!ctx->busy && bufchain_size(&ctx->queued_data)) {
bufchain_prefix(&ctx->queued_data, &senddata, &sendlen);
ctx->buffer = senddata;
ctx->len = sendlen;
SetEvent(ctx->ev_from_main);
ctx->busy = TRUE;
}
}
void try_output(int is_stderr)
{
struct output_data *data = (is_stderr ? &edata : &odata);
void *senddata;
int sendlen;
if (!data->busy) {
bufchain_prefix(is_stderr ? &stderr_data : &stdout_data,
&senddata, &sendlen);
data->buffer = senddata;
data->len = sendlen;
SetEvent(data->eventback);
data->busy = 1;
}
}
static void handle_socket_unfreeze(void *psv)
{
Handle_Socket ps = (Handle_Socket) psv;
void *data;
int len;
/*
* If we've been put into a state other than THAWING since the
* last callback, then we're done.
*/
if (ps->frozen != THAWING)
return;
/*
* Get some of the data we've buffered.
*/
bufchain_prefix(&ps->inputdata, &data, &len);
assert(len > 0);
/*
* Hand it off to the plug. Be careful of re-entrance - that might
* have the effect of trying to close this socket.
*/
ps->defer_close = TRUE;
plug_receive(ps->plug, 0, data, len);
bufchain_consume(&ps->inputdata, len);
ps->defer_close = FALSE;
if (ps->deferred_close) {
sk_handle_close(ps);
return;
}
if (bufchain_size(&ps->inputdata) > 0) {
/*
* If there's still data in our buffer, stay in THAWING state,
* and reschedule ourself.
*/
queue_toplevel_callback(handle_socket_unfreeze, ps);
} else {
/*
* Otherwise, we've successfully thawed!
*/
ps->frozen = UNFROZEN;
handle_unthrottle(ps->recv_h, 0);
}
}
static void handle_try_output(struct handle_output *ctx)
{
void *senddata;
int sendlen;
if (!ctx->busy && bufchain_size(&ctx->queued_data)) {
bufchain_prefix(&ctx->queued_data, &senddata, &sendlen);
ctx->buffer = senddata;
ctx->len = sendlen;
SetEvent(ctx->ev_from_main);
ctx->busy = TRUE;
} else if (!ctx->busy && bufchain_size(&ctx->queued_data) == 0 &&
ctx->outgoingeof == EOF_PENDING) {
CloseHandle(ctx->h);
ctx->h = INVALID_HANDLE_VALUE;
ctx->outgoingeof = EOF_SENT;
}
}
void try_output(int is_stderr)
{
bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
int fd = (is_stderr ? 2 : 1);
void *senddata;
int sendlen, ret;
if (bufchain_size(chain) == 0)
return;
bufchain_prefix(chain, &senddata, &sendlen);
ret = write(fd, senddata, sendlen);
if (ret > 0)
bufchain_consume(chain, ret);
else if (ret < 0) {
perror(is_stderr ? "stderr: write" : "stdout: write");
exit(1);
}
}
static void sk_proxy_set_frozen(Socket s, int is_frozen)
{
Proxy_Socket ps = (Proxy_Socket)s;
if (ps->state != PROXY_STATE_ACTIVE) {
ps->freeze = is_frozen;
return;
}
/* handle any remaining buffered recv data first */
if (bufchain_size(&ps->pending_input_data) > 0) {
ps->freeze = is_frozen;
/* loop while we still have buffered data, and while we are
* unfrozen. the plug_receive call in the loop could result
* in a call back into this function refreezing the socket,
* so we have to check each time.
*/
while (!ps->freeze && bufchain_size(&ps->pending_input_data) > 0) {
void *data;
char databuf[512];
int len;
bufchain_prefix(&ps->pending_input_data, &data, &len);
if (len > lenof(databuf))
len = lenof(databuf);
memcpy(databuf, data, len);
bufchain_consume(&ps->pending_input_data, len);
plug_receive(ps->plug, 0, databuf, len);
}
/* if we're still frozen, we'll have to wait for another
* call from the backend to finish unbuffering the data.
*/
if (ps->freeze)
return;
}
sk_set_frozen(ps->sub_socket, is_frozen);
}
static void handle_socket_unfreeze(void *psv)
{
Handle_Socket ps = (Handle_Socket) psv;
void *data;
int len, new_backlog;
/*
* If we've been put into a state other than THAWING since the
* last callback, then we're done.
*/
if (ps->frozen != THAWING)
return;
/*
* Get some of the data we've buffered.
*/
bufchain_prefix(&ps->inputdata, &data, &len);
assert(len > 0);
/*
* Hand it off to the plug.
*/
new_backlog = plug_receive(ps->plug, 0, data, len);
if (bufchain_size(&ps->inputdata) > 0) {
/*
* If there's still data in our buffer, stay in THAWING state,
* and reschedule ourself.
*/
queue_toplevel_callback(handle_socket_unfreeze, ps);
} else {
/*
* Otherwise, we've successfully thawed!
*/
ps->frozen = UNFROZEN;
handle_unthrottle(ps->recv_h, new_backlog);
}
}
static int localproxy_try_send(Local_Proxy_Socket ps)
{
int sent = 0;
while (bufchain_size(&ps->pending_output_data) > 0) {
void *data;
int len, ret;
bufchain_prefix(&ps->pending_output_data, &data, &len);
ret = write(ps->to_cmd, data, len);
if (ret < 0 && errno != EWOULDBLOCK) {
plug_closing(ps->plug, strerror(errno), errno, 0);
return 0;
} else if (ret <= 0) {
break;
} else {
bufchain_consume(&ps->pending_output_data, ret);
sent += ret;
}
}
if (ps->outgoingeof == EOF_PENDING) {
del234(localproxy_by_tofd, ps);
close(ps->to_cmd);
uxsel_del(ps->to_cmd);
ps->to_cmd = -1;
ps->outgoingeof = EOF_SENT;
}
if (bufchain_size(&ps->pending_output_data) == 0)
uxsel_del(ps->to_cmd);
else
uxsel_set(ps->to_cmd, 2, localproxy_select_result);
return sent;
}
static void logfopen_callback(void *handle, int mode)
{
struct LogContext *ctx = (struct LogContext *)handle;
char buf[256], *event;
struct tm tm;
const char *fmode;
int shout = FALSE;
if (mode == 0) {
ctx->state = L_ERROR; /* disable logging */
} else {
fmode = (mode == 1 ? "ab" : "wb");
ctx->lgfp = f_open(ctx->currlogfilename, fmode, FALSE);
if (ctx->lgfp) {
ctx->state = L_OPEN;
} else {
ctx->state = L_ERROR;
shout = TRUE;
}
}
if (ctx->state == L_OPEN) {
/* Write header line into log file. */
tm = ltime();
strftime(buf, 24, "%Y.%m.%d %H:%M:%S", &tm);
logprintf(ctx, "=~=~=~=~=~=~=~=~=~=~=~= PuTTY log %s"
" =~=~=~=~=~=~=~=~=~=~=~=\r\n", buf);
}
event = dupprintf(MPEXT_BOM "%s session log (%s mode) to file: %s",
ctx->state == L_ERROR ?
(mode == 0 ? "Disabled writing" : "Error writing") :
(mode == 1 ? "Appending" : "Writing new"),
(ctx->logtype == LGTYP_ASCII ? "ASCII" :
ctx->logtype == LGTYP_DEBUG ? "raw" :
ctx->logtype == LGTYP_PACKETS ? "SSH packets" :
ctx->logtype == LGTYP_SSHRAW ? "SSH raw data" :
"unknown"),
filename_to_str(ctx->currlogfilename));
logevent(ctx->frontend, event);
if (shout) {
/*
* If we failed to open the log file due to filesystem error
* (as opposed to user action such as clicking Cancel in the
* askappend box), we should log it more prominently. We do
* this by sending it to the same place that stderr output
* from the main session goes (so, either a console tool's
* actual stderr, or a terminal window).
*
* Of course this is one case in which that policy won't cause
* it to turn up embarrassingly in a log file of real server
* output, because the whole point is that we haven't managed
* to open any such log file :-)
*/
from_backend(ctx->frontend, 1, event, strlen(event));
from_backend(ctx->frontend, 1, "\r\n", 2);
}
sfree(event);
/*
* Having either succeeded or failed in opening the log file,
* we should write any queued data out.
*/
assert(ctx->state != L_OPENING); /* make _sure_ it won't be requeued */
while (bufchain_size(&ctx->queue)) {
void *data;
int len;
bufchain_prefix(&ctx->queue, &data, &len);
logwrite(ctx, data, len);
bufchain_consume(&ctx->queue, len);
}
}
int main(int argc, char **argv)
{
int masterr, masterw, slaver, slavew, pid;
char ptyname[FILENAME_MAX];
bufchain tochild, tostdout;
int tochild_active, tostdout_active, fromstdin_active, fromchild_active;
int exitcode = -1;
pid_t childpid = -1;
--argc, ++argv; /* point at argument after "--" */
/*
* Allocate the pipe for transmitting signals back to the
* top-level select loop.
*/
if (pipe(signalpipe) < 0) {
perror("pipe");
return 1;
}
/*
* Now that pipe exists, we can set up the SIGCHLD handler to
* write to one end of it. We needn't already know details like
* which child pid we're waiting for, because we don't need that
* until we respond to reading the far end of the pipe in the
* main select loop.
*/
signal(SIGCHLD, sigchld);
/*
* Allocate the pty or pipes.
*/
masterr = pty_get(ptyname);
masterw = dup(masterr);
slaver = open(ptyname, O_RDWR);
slavew = dup(slaver);
if (slaver < 0) {
perror("slave pty: open");
return 1;
}
bufchain_init(&tochild);
bufchain_init(&tostdout);
tochild_active = tostdout_active = TRUE;
fromchild_active = fromstdin_active = TRUE;
/*
* Fork and execute the command.
*/
pid = fork();
if (pid < 0) {
perror("fork");
return 1;
}
if (pid == 0) {
int i;
/*
* We are the child.
*/
close(masterr);
close(masterw);
fcntl(slaver, F_SETFD, 0); /* don't close on exec */
fcntl(slavew, F_SETFD, 0); /* don't close on exec */
close(0);
dup2(slaver, 0);
close(1);
dup2(slavew, 1);
int fd;
close(2);
dup2(slavew, 2);
setsid();
setpgid(0, 0);
tcsetpgrp(0, getpgrp());
if ((fd = open("/dev/tty", O_RDWR)) >= 0) {
ioctl(fd, TIOCNOTTY);
close(fd);
}
ioctl(slavew, TIOCSCTTY);
/* Close everything _else_, for tidiness. */
for (i = 3; i < 1024; i++)
close(i);
if (argc > 0) {
execvp(argv[0], argv); /* assumes argv has trailing NULL */
} else {
execl(getenv("SHELL"), getenv("SHELL"), NULL);
}
/*
* If we're here, exec has gone badly foom.
*/
perror("exec");
exit(127);
}
/*
* Now we're the parent. Close the slave fds and start copying
* stuff back and forth.
*/
close(slaver);
close(slavew);
childpid = pid;
tcgetattr(0, &oldattrs);
newattrs = oldattrs;
newattrs.c_iflag &= ~(IXON | IXOFF | ICRNL | INLCR);
newattrs.c_oflag &= ~(ONLCR | OCRNL);
newattrs.c_lflag &= ~(ISIG | ICANON | ECHO);
atexit(attrsonexit);
tcsetattr(0, TCSADRAIN, &newattrs);
while (1) {
fd_set rset, wset;
char buf[65536];
int maxfd, ret;
FD_ZERO(&rset);
FD_ZERO(&wset);
maxfd = 0;
FD_SET(signalpipe[0], &rset);
maxfd = max(signalpipe[0]+1, maxfd);
if (tochild_active && bufchain_size(&tochild)) {
FD_SET(masterw, &wset);
maxfd = max(masterw+1, maxfd);
}
if (tostdout_active && bufchain_size(&tostdout)) {
FD_SET(1, &wset);
maxfd = max(1+1, maxfd);
}
if (fromstdin_active && bufchain_size(&tochild) < LOCALBUF_LIMIT) {
FD_SET(0, &rset);
maxfd = max(0+1, maxfd);
}
if (fromchild_active && bufchain_size(&tostdout) < LOCALBUF_LIMIT) {
FD_SET(masterr, &rset);
maxfd = max(masterr+1, maxfd);
}
do {
ret = select(maxfd, &rset, &wset, NULL, NULL);
} while (ret < 0 && (errno == EINTR || errno == EAGAIN));
if (ret < 0) {
perror("select");
return 1;
}
if (FD_ISSET(masterr, &rset)) {
if (FD_ISSET(masterr, &rset)) {
ret = read(masterr, buf, sizeof(buf));
if (ret <= 0) {
/*
* EIO from a pty master just means end of
* file, annoyingly. Why can't it report
* ordinary EOF?
*/
if (errno == EIO)
ret = 0;
if (ret < 0) {
perror("child process: read");
}
close(masterr);
fromchild_active = FALSE;
ret = 0;
}
} else
ret = 0;
if (ret) {
bufchain_add(&tostdout, buf, ret);
}
}
if (FD_ISSET(0, &rset)) {
if (FD_ISSET(0, &rset)) {
ret = read(0, buf, sizeof(buf));
if (ret <= 0) {
if (ret < 0) {
perror("stdin: read");
}
close(0);
fromstdin_active = FALSE;
ret = 0;
}
} else
ret = 0;
if (ret) {
bufchain_add(&tochild, buf, ret);
}
}
if (FD_ISSET(1, &wset)) {
void *data;
int len, ret;
bufchain_prefix(&tostdout, &data, &len);
if ((ret = write(1, data, len)) < 0) {
perror("stdout: write");
close(1);
close(masterr);
tostdout_active = fromchild_active = FALSE;
} else
bufchain_consume(&tostdout, ret);
}
if (FD_ISSET(masterw, &wset)) {
void *data;
int len;
bufchain_prefix(&tochild, &data, &len);
if ((ret = write(masterw, data, len)) < 0) {
perror("child process: write");
close(0);
close(masterw);
tochild_active = fromstdin_active = FALSE;
} else
bufchain_consume(&tochild, ret);
}
if (FD_ISSET(signalpipe[0], &rset)) {
ret = read(signalpipe[0], buf, 1);
if (ret == 1 && buf[0] == 'C') {
int pid, code;
pid = wait(&code); /* reap the exit code */
if (pid == childpid)
exitcode = code;
}
}
/*
* If there can be no further data from a direction (the
* input fd has been closed and the buffered data is used
* up) but its output fd is still open, close it.
*/
if (!fromstdin_active && !bufchain_size(&tochild) && tochild_active) {
tochild_active = FALSE;
close(masterw);
}
if (!fromchild_active && !bufchain_size(&tostdout) && tostdout_active){
tostdout_active = FALSE;
close(1);
}
/*
* Termination condition with pipes is that there's still
* data flowing in at least one direction.
*
* Termination condition for a pty-based run is that the
* child process hasn't yet terminated and/or there is
* still buffered data to send.
*/
if (exitcode < 0)
/* process is still active */;
else if (tochild_active && bufchain_size(&tochild))
/* data still to be sent to child's children */;
else if (tostdout_active && bufchain_size(&tostdout))
/* data still to be sent to stdout */;
else
break; /* terminate */
}
close(masterw);
close(masterr);
if (exitcode < 0) {
int pid, code;
pid = wait(&code);
exitcode = code;
}
return (WIFEXITED(exitcode) ? WEXITSTATUS(exitcode) :
128 | WTERMSIG(exitcode));
}