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putty
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Extensive changes that _should_ fix the socket buffering problems, 

by ceasing to listen on input channels if the corresponding output
channel isn't accepting data. Has had basic check-I-didn't-actually-
break-anything-too-badly testing, but hasn't been genuinely tested
in stress conditions (because concocting stress conditions is non-
trivial).

[originally from svn r1198]
This commit is contained in:
Simon Tatham 2001-08-25 17:09:23 +00:00
Родитель 7ff3999e49
Коммит c87fa98d09
17 изменённых файлов: 929 добавлений и 259 удалений
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96
misc.c
Просмотреть файл

@ -1,8 +1,104 @@
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "putty.h"
/*
* Generic routines to deal with send buffers: a linked list of
* smallish blocks, with the operations
*
* - add an arbitrary amount of data to the end of the list
* - remove the first N bytes from the list
* - return a (pointer,length) pair giving some initial data in
* the list, suitable for passing to a send or write system
* call
* - return the current size of the buffer chain in bytes
*/
#define BUFFER_GRANULE 512
struct bufchain_granule {
struct bufchain_granule *next;
int buflen, bufpos;
char buf[BUFFER_GRANULE];
};
void bufchain_init(bufchain *ch)
{
ch->head = ch->tail = NULL;
ch->buffersize = 0;
}
void bufchain_clear(bufchain *ch)
{
struct bufchain_granule *b;
while (ch->head) {
b = ch->head;
ch->head = ch->head->next;
sfree(b);
}
ch->tail = NULL;
ch->buffersize = 0;
}
int bufchain_size(bufchain *ch)
{
return ch->buffersize;
}
void bufchain_add(bufchain *ch, void *data, int len)
{
char *buf = (char *)data;
ch->buffersize += len;
if (ch->tail && ch->tail->buflen < BUFFER_GRANULE) {
int copylen = min(len, BUFFER_GRANULE - ch->tail->buflen);
memcpy(ch->tail->buf + ch->tail->buflen, buf, copylen);
buf += copylen;
len -= copylen;
ch->tail->buflen += copylen;
}
while (len > 0) {
int grainlen = min(len, BUFFER_GRANULE);
struct bufchain_granule *newbuf;
newbuf = smalloc(sizeof(struct bufchain_granule));
newbuf->bufpos = 0;
newbuf->buflen = grainlen;
memcpy(newbuf->buf, buf, grainlen);
buf += grainlen;
len -= grainlen;
if (ch->tail)
ch->tail->next = newbuf;
else
ch->head = ch->tail = newbuf;
newbuf->next = NULL;
ch->tail = newbuf;
}
}
void bufchain_consume(bufchain *ch, int len)
{
assert(ch->buffersize >= len);
assert(ch->head != NULL && ch->head->bufpos + len <= ch->head->buflen);
ch->head->bufpos += len;
ch->buffersize -= len;
if (ch->head->bufpos >= ch->head->buflen) {
struct bufchain_granule *tmp = ch->head;
ch->head = tmp->next;
sfree(tmp);
if (!ch->head)
ch->tail = NULL;
}
}
void bufchain_prefix(bufchain *ch, void **data, int *len)
{
*len = ch->head->buflen - ch->head->bufpos;
*data = ch->head->buf + ch->head->bufpos;
}
/*
* My own versions of malloc, realloc and free. Because I want
* malloc and realloc to bomb out and exit the program if they run

12
misc.h
Просмотреть файл

@ -3,6 +3,18 @@
#include "puttymem.h"
struct bufchain_granule;
typedef struct bufchain_tag {
struct bufchain_granule *head, *tail;
int buffersize; /* current amount of buffered data */
} bufchain;
void bufchain_init(bufchain *ch);
void bufchain_clear(bufchain *ch);
int bufchain_size(bufchain *ch);
void bufchain_add(bufchain *ch, void *data, int len);
void bufchain_prefix(bufchain *ch, void **data, int *len);
void bufchain_consume(bufchain *ch, int len);
/*
* Debugging functions.

29
network.h
Просмотреть файл

@ -24,8 +24,8 @@ struct socket_function_table {
/* if p is NULL, it doesn't change the plug */
/* but it does return the one it's using */
void (*close) (Socket s);
void (*write) (Socket s, char *data, int len);
void (*write_oob) (Socket s, char *data, int len);
int (*write) (Socket s, char *data, int len);
int (*write_oob) (Socket s, char *data, int len);
void (*flush) (Socket s);
/* ignored by tcp, but vital for ssl */
char *(*socket_error) (Socket s);
@ -48,6 +48,12 @@ struct plug_function_table {
* - urgent==2. `data' points to `len' bytes of data,
* the first of which was the one at the Urgent mark.
*/
void (*sent) (Plug p, int bufsize);
/*
* The `sent' function is called when the pending send backlog
* on a socket is cleared or partially cleared. The new backlog
* size is passed in the `bufsize' parameter.
*/
int (*accepting)(Plug p, struct sockaddr *addr, void *sock);
/*
* returns 0 if the host at address addr is a valid host for connecting or error
@ -76,6 +82,7 @@ Socket sk_register(void *sock, Plug plug);
#ifdef DEFINE_PLUG_METHOD_MACROS
#define plug_closing(p,msg,code,callback) (((*p)->closing) (p, msg, code, callback))
#define plug_receive(p,urgent,buf,len) (((*p)->receive) (p, urgent, buf, len))
#define plug_sent(p,bufsize) (((*p)->sent) (p, bufsize))
#define plug_accepting(p, addr, sock) (((*p)->accepting)(p, addr, sock))
#endif
@ -99,10 +106,20 @@ char *sk_addr_error(SockAddr addr);
/*
* Set the `frozen' flag on a socket. A frozen socket is one in
* which all sends are buffered and receives are ignored. This is
* so that (for example) a new port-forwarding can sit in limbo
* until its associated SSH channel is ready, and then pending data
* can be sent on.
* which all READABLE notifications are ignored, so that data is
* not accepted from the peer until the socket is unfrozen. This
* exists for two purposes:
*
* - Port forwarding: when a local listening port receives a
* connection, we do not want to receive data from the new
* socket until we have somewhere to send it. Hence, we freeze
* the socket until its associated SSH channel is ready; then we
* unfreeze it and pending data is delivered.
*
* - Socket buffering: if an SSH channel (or the whole connection)
* backs up or presents a zero window, we must freeze the
* associated local socket in order to avoid unbounded buffer
* growth.
*/
void sk_set_frozen(Socket sock, int is_frozen);

167
plink.c
Просмотреть файл

@ -15,6 +15,8 @@
#include "storage.h"
#include "tree234.h"
#define MAX_STDIN_BACKLOG 4096
void fatalbox(char *p, ...)
{
va_list ap;
@ -125,20 +127,6 @@ DWORD orig_console_mode;
WSAEVENT netevent;
void from_backend(int is_stderr, char *data, int len)
{
int pos;
DWORD ret;
HANDLE h = (is_stderr ? errhandle : outhandle);
pos = 0;
while (pos < len) {
if (!WriteFile(h, data + pos, len - pos, &ret, NULL))
return; /* give up in panic */
pos += ret;
}
}
int term_ldisc(int mode)
{
return FALSE;
@ -160,12 +148,6 @@ void ldisc_update(int echo, int edit)
SetConsoleMode(inhandle, mode);
}
struct input_data {
DWORD len;
char buffer[4096];
HANDLE event, eventback;
};
static int get_line(const char *prompt, char *str, int maxlen, int is_pw)
{
HANDLE hin, hout;
@ -216,6 +198,12 @@ static int get_line(const char *prompt, char *str, int maxlen, int is_pw)
return 1;
}
struct input_data {
DWORD len;
char buffer[4096];
HANDLE event, eventback;
};
static DWORD WINAPI stdin_read_thread(void *param)
{
struct input_data *idata = (struct input_data *) param;
@ -235,6 +223,78 @@ static DWORD WINAPI stdin_read_thread(void *param)
return 0;
}
struct output_data {
DWORD len, lenwritten;
int writeret;
char *buffer;
int is_stderr, done;
HANDLE event, eventback;
int busy;
};
static DWORD WINAPI stdout_write_thread(void *param)
{
struct output_data *odata = (struct output_data *) param;
HANDLE outhandle, errhandle;
outhandle = GetStdHandle(STD_OUTPUT_HANDLE);
errhandle = GetStdHandle(STD_ERROR_HANDLE);
while (1) {
WaitForSingleObject(odata->eventback, INFINITE);
if (odata->done)
break;
odata->writeret =
WriteFile(odata->is_stderr ? errhandle : outhandle,
odata->buffer, odata->len, &odata->lenwritten, NULL);
SetEvent(odata->event);
}
return 0;
}
bufchain stdout_data, stderr_data;
struct output_data odata, edata;
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;
}
}
int from_backend(int is_stderr, char *data, int len)
{
int pos;
DWORD ret;
HANDLE h = (is_stderr ? errhandle : outhandle);
void *writedata;
int writelen;
int osize, esize;
if (is_stderr) {
bufchain_add(&stderr_data, data, len);
try_output(1);
} else {
bufchain_add(&stdout_data, data, len);
try_output(0);
}
osize = bufchain_size(&stdout_data);
esize = bufchain_size(&stderr_data);
return osize + esize;
}
/*
* Short description of parameters.
*/
@ -275,10 +335,11 @@ int main(int argc, char **argv)
{
WSADATA wsadata;
WORD winsock_ver;
WSAEVENT stdinevent;
HANDLE handles[2];
DWORD threadid;
WSAEVENT stdinevent, stdoutevent, stderrevent;
HANDLE handles[4];
DWORD in_threadid, out_threadid, err_threadid;
struct input_data idata;
int reading;
int sending;
int portnumber = -1;
SOCKET *sklist;
@ -554,6 +615,8 @@ int main(int argc, char **argv)
connopen = 1;
stdinevent = CreateEvent(NULL, FALSE, FALSE, NULL);
stdoutevent = CreateEvent(NULL, FALSE, FALSE, NULL);
stderrevent = CreateEvent(NULL, FALSE, FALSE, NULL);
inhandle = GetStdHandle(STD_INPUT_HANDLE);
outhandle = GetStdHandle(STD_OUTPUT_HANDLE);
@ -568,7 +631,33 @@ int main(int argc, char **argv)
*/
handles[0] = netevent;
handles[1] = stdinevent;
handles[2] = stdoutevent;
handles[3] = stderrevent;
sending = FALSE;
/*
* Create spare threads to write to stdout and stderr, so we
* can arrange asynchronous writes.
*/
odata.event = stdoutevent;
odata.eventback = CreateEvent(NULL, FALSE, FALSE, NULL);
odata.is_stderr = 0;
odata.busy = odata.done = 0;
if (!CreateThread(NULL, 0, stdout_write_thread,
&odata, 0, &out_threadid)) {
fprintf(stderr, "Unable to create output thread\n");
exit(1);
}
edata.event = stderrevent;
edata.eventback = CreateEvent(NULL, FALSE, FALSE, NULL);
edata.is_stderr = 1;
edata.busy = edata.done = 0;
if (!CreateThread(NULL, 0, stdout_write_thread,
&edata, 0, &err_threadid)) {
fprintf(stderr, "Unable to create error output thread\n");
exit(1);
}
while (1) {
int n;
@ -592,14 +681,14 @@ int main(int argc, char **argv)
idata.event = stdinevent;
idata.eventback = CreateEvent(NULL, FALSE, FALSE, NULL);
if (!CreateThread(NULL, 0, stdin_read_thread,
&idata, 0, &threadid)) {
fprintf(stderr, "Unable to create second thread\n");
&idata, 0, &in_threadid)) {
fprintf(stderr, "Unable to create input thread\n");
exit(1);
}
sending = TRUE;
}
n = WaitForMultipleObjects(2, handles, FALSE, INFINITE);
n = WaitForMultipleObjects(4, handles, FALSE, INFINITE);
if (n == 0) {
WSANETWORKEVENTS things;
SOCKET socket;
@ -655,13 +744,39 @@ int main(int argc, char **argv)
}
}
} else if (n == 1) {
reading = 0;
noise_ultralight(idata.len);
if (idata.len > 0) {
back->send(idata.buffer, idata.len);
} else {
back->special(TS_EOF);
}
} else if (n == 2) {
odata.busy = 0;
if (!odata.writeret) {
fprintf(stderr, "Unable to write to standard output\n");
exit(0);
}
bufchain_consume(&stdout_data, odata.lenwritten);
if (bufchain_size(&stdout_data) > 0)
try_output(0);
back->unthrottle(bufchain_size(&stdout_data) +
bufchain_size(&stderr_data));
} else if (n == 3) {
edata.busy = 0;
if (!edata.writeret) {
fprintf(stderr, "Unable to write to standard output\n");
exit(0);
}
bufchain_consume(&stderr_data, edata.lenwritten);
if (bufchain_size(&stderr_data) > 0)
try_output(1);
back->unthrottle(bufchain_size(&stdout_data) +
bufchain_size(&stderr_data));
}
if (!reading && back->sendbuffer() < MAX_STDIN_BACKLOG) {
SetEvent(idata.eventback);
reading = 1;
}
if (!connopen || back->socket() == NULL)
break; /* we closed the connection */

55
portfwd.c
Просмотреть файл

@ -52,9 +52,6 @@
(cp)[0] = (value) >> 8, \
(cp)[1] = (value) )
extern void sshfwd_close(void *);
extern void sshfwd_write(void *, char *, int);
struct pfwd_queue {
struct pfwd_queue *next;
char *buf;
@ -66,6 +63,7 @@ struct PFwdPrivate {
void *c; /* (channel) data used by ssh.c */
Socket s;
char hostname[128];
int throttled, throttle_override;
int port;
int ready;
struct pfwd_queue *waiting;
@ -92,12 +90,22 @@ static int pfd_closing(Plug plug, char *error_msg, int error_code,
static int pfd_receive(Plug plug, int urgent, char *data, int len)
{
struct PFwdPrivate *pr = (struct PFwdPrivate *) plug;
if (pr->ready)
sshfwd_write(pr->c, data, len);
if (pr->ready) {
if (sshfwd_write(pr->c, data, len) > 0) {
pr->throttled = 1;
sk_set_frozen(pr->s, 1);
}
}
return 1;
}
static void pfd_sent(Plug plug, int bufsize)
{
struct PFwdPrivate *pr = (struct PFwdPrivate *) plug;
sshfwd_unthrottle(pr->c, bufsize);
}
/*
* Called when receiving a PORT OPEN from the server
*/
@ -106,6 +114,7 @@ char *pfd_newconnect(Socket *s, char *hostname, int port, void *c)
static struct plug_function_table fn_table = {
pfd_closing,
pfd_receive,
pfd_sent,
NULL
};
@ -125,6 +134,7 @@ char *pfd_newconnect(Socket *s, char *hostname, int port, void *c)
*/
pr = (struct PFwdPrivate *) smalloc(sizeof(struct PFwdPrivate));
pr->fn = &fn_table;
pr->throttled = pr->throttle_override = 0;
pr->ready = 1;
pr->c = c;
@ -149,6 +159,7 @@ static int pfd_accepting(Plug p, struct sockaddr *addr, void *sock)
static struct plug_function_table fn_table = {
pfd_closing,
pfd_receive,
pfd_sent,
NULL
};
struct PFwdPrivate *pr, *org;
@ -175,6 +186,7 @@ static int pfd_accepting(Plug p, struct sockaddr *addr, void *sock)
strcpy(pr->hostname, org->hostname);
pr->port = org->port;
pr->throttled = pr->throttle_override = 0;
pr->ready = 0;
pr->waiting = NULL;
@ -200,6 +212,7 @@ char *pfd_addforward(char *desthost, int destport, int port)
static struct plug_function_table fn_table = {
pfd_closing,
pfd_receive, /* should not happen... */
pfd_sent, /* also should not happen */
pfd_accepting
};
@ -215,6 +228,7 @@ char *pfd_addforward(char *desthost, int destport, int port)
pr->c = NULL;
strcpy(pr->hostname, desthost);
pr->port = destport;
pr->throttled = pr->throttle_override = 0;
pr->ready = 0;
pr->waiting = NULL;
@ -243,15 +257,36 @@ void pfd_close(Socket s)
sk_close(s);
}
void pfd_unthrottle(Socket s)
{
struct PFwdPrivate *pr;
if (!s)
return;
pr = (struct PFwdPrivate *) sk_get_private_ptr(s);
pr->throttled = 0;
sk_set_frozen(s, pr->throttled || pr->throttle_override);
}
void pfd_override_throttle(Socket s, int enable)
{
struct PFwdPrivate *pr;
if (!s)
return;
pr = (struct PFwdPrivate *) sk_get_private_ptr(s);
pr->throttle_override = enable;
sk_set_frozen(s, pr->throttled || pr->throttle_override);
}
/*
* Called to send data down the raw connection.
*/
void pfd_send(Socket s, char *data, int len)
int pfd_send(Socket s, char *data, int len)
{
if (s == NULL)
return;
sk_write(s, data, len);
return 0;
return sk_write(s, data, len);
}

15
psftp.c
Просмотреть файл

@ -16,6 +16,13 @@
#include "sftp.h"
#include "int64.h"
/*
* Since SFTP is a request-response oriented protocol, it requires
* no buffer management: when we send data, we stop and wait for an
* acknowledgement _anyway_, and so we can't possibly overfill our
* send buffer.
*/
/* ----------------------------------------------------------------------
* String handling routines.
*/
@ -912,7 +919,7 @@ static unsigned char *outptr; /* where to put the data */
static unsigned outlen; /* how much data required */
static unsigned char *pending = NULL; /* any spare data */
static unsigned pendlen = 0, pendsize = 0; /* length and phys. size of buffer */
void from_backend(int is_stderr, char *data, int datalen)
int from_backend(int is_stderr, char *data, int datalen)
{
unsigned char *p = (unsigned char *) data;
unsigned len = (unsigned) datalen;
@ -923,14 +930,14 @@ void from_backend(int is_stderr, char *data, int datalen)
*/
if (is_stderr) {
fwrite(data, 1, len, stderr);
return;
return 0;
}
/*
* If this is before the real session begins, just return.
*/
if (!outptr)
return;
return 0;
if (outlen > 0) {
unsigned used = outlen;
@ -954,6 +961,8 @@ void from_backend(int is_stderr, char *data, int datalen)
memcpy(pending + pendlen, p, len);
pendlen += len;
}
return 0;
}
int sftp_recvdata(char *buf, int len)
{

12
putty.h
Просмотреть файл

@ -198,12 +198,20 @@ enum {
typedef struct {
char *(*init) (char *host, int port, char **realhost);
void (*send) (char *buf, int len);
/* back->send() returns the current amount of buffered data. */
int (*send) (char *buf, int len);
/* back->sendbuffer() does the same thing but without attempting a send */
int (*sendbuffer) (void);
void (*size) (void);
void (*special) (Telnet_Special code);
Socket(*socket) (void);
int (*sendok) (void);
int (*ldisc) (int);
/*
* back->unthrottle() tells the back end that the front end
* buffer is clearing.
*/
void (*unthrottle) (int);
int default_port;
} Backend;
@ -436,7 +444,7 @@ void term_do_paste(void);
void term_paste(void);
void term_nopaste(void);
int term_ldisc(int option);
void from_backend(int is_stderr, char *data, int len);
int from_backend(int is_stderr, char *data, int len);
void logfopen(void);
void logfclose(void);
void term_copyall(void);

27
raw.c
Просмотреть файл

@ -11,13 +11,17 @@
#define TRUE 1
#endif
#define RAW_MAX_BACKLOG 4096
static Socket s = NULL;
static int raw_bufsize;
static void raw_size(void);
static void c_write(char *buf, int len)
{
from_backend(0, buf, len);
int backlog = from_backend(0, buf, len);
sk_set_frozen(s, backlog > RAW_MAX_BACKLOG);
}
static int raw_closing(Plug plug, char *error_msg, int error_code,
@ -83,13 +87,23 @@ static char *raw_init(char *host, int port, char **realhost)
/*
* Called to send data down the raw connection.
*/
static void raw_send(char *buf, int len)
static int raw_send(char *buf, int len)
{
if (s == NULL)
return;
sk_write(s, buf, len);
raw_bufsize = sk_write(s, buf, len);
return raw_bufsize;
}
/*
* Called to query the current socket sendability status.
*/
static int raw_sendbuffer(void)
{
return raw_bufsize;
}
/*
@ -120,6 +134,11 @@ static int raw_sendok(void)
return 1;
}
static void raw_unthrottle(int backlog)
{
sk_set_frozen(s, backlog > RAW_MAX_BACKLOG);
}
static int raw_ldisc(int option)
{
if (option == LD_EDIT || option == LD_ECHO)
@ -130,10 +149,12 @@ static int raw_ldisc(int option)
Backend raw_backend = {
raw_init,
raw_send,
raw_sendbuffer,
raw_size,
raw_special,
raw_socket,
raw_sendok,
raw_ldisc,
raw_unthrottle,
1
};

31
rlogin.c
Просмотреть файл

@ -12,13 +12,17 @@
#define TRUE 1
#endif
#define RLOGIN_MAX_BACKLOG 4096
static Socket s = NULL;
static int rlogin_bufsize;
static void rlogin_size(void);
static void c_write(char *buf, int len)
{
from_backend(0, buf, len);
int backlog = from_backend(0, buf, len);
sk_set_frozen(s, backlog > RLOGIN_MAX_BACKLOG);
}
static int rlogin_closing(Plug plug, char *error_msg, int error_code,
@ -122,7 +126,7 @@ static char *rlogin_init(char *host, int port, char **realhost)
sk_write(s, "/", 1);
for (p = cfg.termspeed; isdigit(*p); p++);
sk_write(s, cfg.termspeed, p - cfg.termspeed);
sk_write(s, &z, 1);
rlogin_bufsize = sk_write(s, &z, 1);
}
return NULL;
@ -131,13 +135,23 @@ static char *rlogin_init(char *host, int port, char **realhost)
/*
* Called to send data down the rlogin connection.
*/
static void rlogin_send(char *buf, int len)
static int rlogin_send(char *buf, int len)
{
if (s == NULL)
return;
sk_write(s, buf, len);
rlogin_bufsize = sk_write(s, buf, len);
return rlogin_bufsize;
}
/*
* Called to query the current socket sendability status.
*/
static int rlogin_sendbuffer(void)
{
return rlogin_bufsize;
}
/*
@ -151,7 +165,7 @@ static void rlogin_size(void)
b[7] = cols & 0xFF;
b[4] = rows >> 8;
b[5] = rows & 0xFF;
sk_write(s, b, 12);
rlogin_bufsize = sk_write(s, b, 12);
return;
}
@ -174,6 +188,11 @@ static int rlogin_sendok(void)
return 1;
}
static void rlogin_unthrottle(int backlog)
{
sk_set_frozen(s, backlog > RLOGIN_MAX_BACKLOG);
}
static int rlogin_ldisc(int option)
{
return 0;
@ -182,10 +201,12 @@ static int rlogin_ldisc(int option)
Backend rlogin_backend = {
rlogin_init,
rlogin_send,
rlogin_sendbuffer,
rlogin_size,
rlogin_special,
rlogin_socket,
rlogin_sendok,
rlogin_ldisc,
rlogin_unthrottle,
1
};

48
scp.c
Просмотреть файл

@ -75,6 +75,12 @@ static void tell_user(FILE * stream, char *fmt, ...);
static void gui_update_stats(char *name, unsigned long size,
int percentage, unsigned long elapsed);
/*
* The maximum amount of queued data we accept before we stop and
* wait for the server to process some.
*/
#define MAX_SCP_BUFSIZE 16384
void logevent(char *string)
{
}
@ -309,7 +315,7 @@ static unsigned char *outptr; /* where to put the data */
static unsigned outlen; /* how much data required */
static unsigned char *pending = NULL; /* any spare data */
static unsigned pendlen = 0, pendsize = 0; /* length and phys. size of buffer */
void from_backend(int is_stderr, char *data, int datalen)
int from_backend(int is_stderr, char *data, int datalen)
{
unsigned char *p = (unsigned char *) data;
unsigned len = (unsigned) datalen;
@ -320,7 +326,7 @@ void from_backend(int is_stderr, char *data, int datalen)
*/
if (is_stderr) {
fwrite(data, 1, len, stderr);
return;
return 0;
}
inbuf_head = 0;
@ -329,7 +335,7 @@ void from_backend(int is_stderr, char *data, int datalen)
* If this is before the real session begins, just return.
*/
if (!outptr)
return;
return 0;
if (outlen > 0) {
unsigned used = outlen;
@ -353,6 +359,19 @@ void from_backend(int is_stderr, char *data, int datalen)
memcpy(pending + pendlen, p, len);
pendlen += len;
}
return 0;
}
static int scp_process_network_event(void)
{
fd_set readfds;
FD_ZERO(&readfds);
FD_SET(scp_ssh_socket, &readfds);
if (select(1, &readfds, NULL, NULL, NULL) < 0)
return 0; /* doom */
select_result((WPARAM) scp_ssh_socket, (LPARAM) FD_READ);
return 1;
}
static int ssh_scp_recv(unsigned char *buf, int len)
{
@ -382,13 +401,8 @@ static int ssh_scp_recv(unsigned char *buf, int len)
}
while (outlen > 0) {
fd_set readfds;
FD_ZERO(&readfds);
FD_SET(scp_ssh_socket, &readfds);
if (select(1, &readfds, NULL, NULL, NULL) < 0)
if (!scp_process_network_event())
return 0; /* doom */
select_result((WPARAM) scp_ssh_socket, (LPARAM) FD_READ);
}
return len;
@ -759,6 +773,8 @@ static void source(char *src)
for (i = 0; i < size; i += 4096) {
char transbuf[4096];
DWORD j, k = 4096;
int bufsize;
if (i + k > size)
k = size - i;
if (!ReadFile(f, transbuf, k, &j, NULL) || j != k) {
@ -766,7 +782,7 @@ static void source(char *src)
printf("\n");
bump("%s: Read error", src);
}
back->send(transbuf, k);
bufsize = back->send(transbuf, k);
if (statistics) {
stat_bytes += k;
if (time(NULL) != stat_lasttime || i + k == size) {
@ -775,6 +791,18 @@ static void source(char *src)
stat_starttime, stat_lasttime);
}
}
/*
* If the network transfer is backing up - that is, the
* remote site is not accepting data as fast as we can
* produce it - then we must loop on network events until
* we have space in the buffer again.
*/
while (bufsize > MAX_SCP_BUFSIZE) {
if (!scp_process_network_event())
bump("%s: Network error occurred", src);
bufsize = back->sendbuffer();
}
}
CloseHandle(f);

374
ssh.c
Просмотреть файл

@ -195,14 +195,43 @@ enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
extern char *x11_init(Socket *, char *, void *);
extern void x11_close(Socket);
extern void x11_send(Socket, char *, int);
extern int x11_send(Socket, char *, int);
extern void x11_invent_auth(char *, int, char *, int);
extern void x11_unthrottle(Socket s);
extern void x11_override_throttle(Socket s, int enable);
extern char *pfd_newconnect(Socket * s, char *hostname, int port, void *c);
extern char *pfd_addforward(char *desthost, int destport, int port);
extern void pfd_close(Socket s);
extern void pfd_send(Socket s, char *data, int len);
extern int pfd_send(Socket s, char *data, int len);
extern void pfd_confirm(Socket s);
extern void pfd_unthrottle(Socket s);
extern void pfd_override_throttle(Socket s, int enable);
/*
* Buffer management constants. There are several of these for
* various different purposes:
*
* - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
* on a local data stream before we throttle the whole SSH
* connection (in SSH1 only). Throttling the whole connection is
* pretty drastic so we set this high in the hope it won't
* happen very often.
*
* - SSH_MAX_BACKLOG is the amount of backlog that must build up
* on the SSH connection itself before we defensively throttle
* _all_ local data streams. This is pretty drastic too (though
* thankfully unlikely in SSH2 since the window mechanism should
* ensure that the server never has any need to throttle its end
* of the connection), so we set this high as well.
*
* - OUR_V2_WINSIZE is the maximum window size we present on SSH2
* channels.
*/
#define SSH1_BUFFER_LIMIT 32768
#define SSH_MAX_BACKLOG 32768
#define OUR_V2_WINSIZE 16384
/*
* Ciphers for SSH2. We miss out single-DES because it isn't
@ -282,11 +311,16 @@ struct ssh_channel {
unsigned remoteid, localid;
int type;
int closes;
union {
struct ssh1_data_channel {
int throttling;
} v1;
struct ssh2_data_channel {
unsigned char *outbuffer;
unsigned outbuflen, outbufsize;
bufchain outbuffer;
unsigned remwindow, remmaxpkt;
unsigned locwindow;
} v2;
} v;
union {
struct ssh_agent_channel {
unsigned char *message;
@ -395,16 +429,22 @@ static unsigned char *deferred_send_data = NULL;
static int deferred_len = 0, deferred_size = 0;
static int ssh_version;
static int ssh1_throttle_count;
static int ssh_overall_bufsize;
static int ssh_throttled_all;
static int ssh1_stdout_throttling;
static void (*ssh_protocol) (unsigned char *in, int inlen, int ispkt);
static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
static void ssh_size(void);
static void ssh_special(Telnet_Special);
static void ssh2_try_send(struct ssh_channel *c);
static int ssh2_try_send(struct ssh_channel *c);
static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
int len);
static void ssh_throttle_all(int enable, int bufsize);
static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
static int (*s_rdpkt) (unsigned char **data, int *datalen);
static int ssh_sendbuffer(void);
static struct rdpkt1_state_tag {
long len, pad, biglen, to_read;
@ -936,9 +976,11 @@ static int s_wrpkt_prepare(void)
static void s_wrpkt(void)
{
int len;
int len, backlog;
len = s_wrpkt_prepare();
sk_write(s, pktout.data, len);
backlog = sk_write(s, pktout.data, len);
if (backlog > SSH_MAX_BACKLOG)
ssh_throttle_all(1, backlog);
}
static void s_wrpkt_defer(void)
@ -1244,8 +1286,12 @@ static int ssh2_pkt_construct(void)
*/
static void ssh2_pkt_send(void)
{
int len = ssh2_pkt_construct();
sk_write(s, pktout.data, len);
int len;
int backlog;
len = ssh2_pkt_construct();
backlog = sk_write(s, pktout.data, len);
if (backlog > SSH_MAX_BACKLOG)
ssh_throttle_all(1, backlog);
}
/*
@ -1276,10 +1322,13 @@ static void ssh2_pkt_defer(void)
*/
static void ssh_pkt_defersend(void)
{
sk_write(s, deferred_send_data, deferred_len);
int backlog;
backlog = sk_write(s, deferred_send_data, deferred_len);
deferred_len = deferred_size = 0;
sfree(deferred_send_data);
deferred_send_data = NULL;
if (backlog > SSH_MAX_BACKLOG)
ssh_throttle_all(1, backlog);
}
#if 0
@ -1579,6 +1628,16 @@ static int ssh_receive(Plug plug, int urgent, char *data, int len)
return 1;
}
static void ssh_sent(Plug plug, int bufsize)
{
/*
* If the send backlog on the SSH socket itself clears, we
* should unthrottle the whole world if it was throttled.
*/
if (bufsize < SSH_MAX_BACKLOG)
ssh_throttle_all(0, bufsize);
}
/*
* Connect to specified host and port.
* Returns an error message, or NULL on success.
@ -1589,7 +1648,9 @@ static char *connect_to_host(char *host, int port, char **realhost)
{
static struct plug_function_table fn_table = {
ssh_closing,
ssh_receive
ssh_receive,
ssh_sent,
NULL
}, *fn_table_ptr = &fn_table;
SockAddr addr;
@ -1646,6 +1707,56 @@ static char *connect_to_host(char *host, int port, char **realhost)
return NULL;
}
/*
* Throttle or unthrottle the SSH connection.
*/
static void ssh1_throttle(int adjust)
{
int old_count = ssh1_throttle_count;
ssh1_throttle_count += adjust;
assert(ssh1_throttle_count >= 0);
if (ssh1_throttle_count && !old_count) {
sk_set_frozen(s, 1);
} else if (!ssh1_throttle_count && old_count) {
sk_set_frozen(s, 0);
}
}
/*
* Throttle or unthrottle _all_ local data streams (for when sends
* on the SSH connection itself back up).
*/
static void ssh_throttle_all(int enable, int bufsize)
{
int i;
struct ssh_channel *c;
if (enable == ssh_throttled_all)
return;
ssh_throttled_all = enable;
ssh_overall_bufsize = bufsize;
if (!ssh_channels)
return;
for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) {
switch (c->type) {
case CHAN_MAINSESSION:
/*
* This is treated separately, outside the switch.
*/
break;
case CHAN_X11:
x11_override_throttle(c->u.x11.s, enable);
break;
case CHAN_AGENT:
/* Agent channels require no buffer management. */
break;
case CHAN_SOCKDATA:
pfd_override_throttle(c->u.x11.s, enable);
break;
}
}
}
/*
* Handle the key exchange and user authentication phases.
*/
@ -2346,15 +2457,35 @@ void sshfwd_close(struct ssh_channel *c)
}
}
void sshfwd_write(struct ssh_channel *c, char *buf, int len)
int sshfwd_write(struct ssh_channel *c, char *buf, int len)
{
if (ssh_version == 1) {
send_packet(SSH1_MSG_CHANNEL_DATA,
PKT_INT, c->remoteid,
PKT_INT, len, PKT_DATA, buf, len, PKT_END);
/*
* In SSH1 we can return 0 here - implying that forwarded
* connections are never individually throttled - because
* the only circumstance that can cause throttling will be
* the whole SSH connection backing up, in which case
* _everything_ will be throttled as a whole.
*/
return 0;
} else {
ssh2_add_channel_data(c, buf, len);
ssh2_try_send(c);
return ssh2_try_send(c);
}
}
void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
{
if (ssh_version == 1) {
if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
c->v.v1.throttling = 0;
ssh1_throttle(-1);
}
} else {
ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
}
}
@ -2540,8 +2671,13 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt)
if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
pktin.type == SSH1_SMSG_STDERR_DATA) {
long len = GET_32BIT(pktin.body);
int bufsize =
from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
pktin.body + 4, len);
if (bufsize > SSH1_BUFFER_LIMIT) {
ssh1_stdout_throttling = 1;
ssh1_throttle(+1);
}
} else if (pktin.type == SSH1_MSG_DISCONNECT) {
ssh_state = SSH_STATE_CLOSED;
logevent("Received disconnect request");
@ -2572,6 +2708,7 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt)
c->remoteid = GET_32BIT(pktin.body);
c->localid = alloc_channel_id();
c->closes = 0;
c->v.v1.throttling = 0;
c->type = CHAN_X11; /* identify channel type */
add234(ssh_channels, c);
send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
@ -2594,6 +2731,7 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt)
c->remoteid = GET_32BIT(pktin.body);
c->localid = alloc_channel_id();
c->closes = 0;
c->v.v1.throttling = 0;
c->type = CHAN_AGENT; /* identify channel type */
c->u.a.lensofar = 0;
add234(ssh_channels, c);
@ -2646,6 +2784,7 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt)
c->remoteid = GET_32BIT(pktin.body);
c->localid = alloc_channel_id();
c->closes = 0;
c->v.v1.throttling = 0;
c->type = CHAN_SOCKDATA; /* identify channel type */
add234(ssh_channels, c);
send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
@ -2706,12 +2845,13 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt)
struct ssh_channel *c;
c = find234(ssh_channels, &i, ssh_channelfind);
if (c) {
int bufsize;
switch (c->type) {
case CHAN_X11:
x11_send(c->u.x11.s, p, len);
bufsize = x11_send(c->u.x11.s, p, len);
break;
case CHAN_SOCKDATA:
pfd_send(c->u.pfd.s, p, len);
bufsize = pfd_send(c->u.pfd.s, p, len);
break;
case CHAN_AGENT:
/* Data for an agent message. Buffer it. */
@ -2764,8 +2904,13 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt)
c->u.a.lensofar = 0;
}
}
bufsize = 0; /* agent channels never back up */
break;
}
if (bufsize > SSH1_BUFFER_LIMIT) {
c->v.v1.throttling = 1;
ssh1_throttle(+1);
}
}
} else if (pktin.type == SSH1_SMSG_SUCCESS) {
/* may be from EXEC_SHELL on some servers */
@ -3272,33 +3417,49 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
int len)
{
if (c->v2.outbufsize < c->v2.outbuflen + len) {
c->v2.outbufsize = c->v2.outbuflen + len + 1024;
c->v2.outbuffer = srealloc(c->v2.outbuffer, c->v2.outbufsize);
}
memcpy(c->v2.outbuffer + c->v2.outbuflen, buf, len);
c->v2.outbuflen += len;
bufchain_add(&c->v.v2.outbuffer, buf, len);
}
/*
* Attempt to send data on an SSH2 channel.
*/
static void ssh2_try_send(struct ssh_channel *c)
static int ssh2_try_send(struct ssh_channel *c)
{
while (c->v2.remwindow > 0 && c->v2.outbuflen > 0) {
unsigned len = c->v2.remwindow;
if (len > c->v2.outbuflen)
len = c->v2.outbuflen;
if (len > c->v2.remmaxpkt)
len = c->v2.remmaxpkt;
while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
int len;
void *data;
bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
if ((unsigned)len > c->v.v2.remwindow)
len = c->v.v2.remwindow;
if ((unsigned)len > c->v.v2.remmaxpkt)
len = c->v.v2.remmaxpkt;
ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
ssh2_pkt_adduint32(c->remoteid);
ssh2_pkt_addstring_start();
ssh2_pkt_addstring_data(c->v2.outbuffer, len);
ssh2_pkt_addstring_data(data, len);
ssh2_pkt_send();
c->v2.outbuflen -= len;
memmove(c->v2.outbuffer, c->v2.outbuffer + len, c->v2.outbuflen);
c->v2.remwindow -= len;
bufchain_consume(&c->v.v2.outbuffer, len);
c->v.v2.remwindow -= len;
}
/*
* After having sent as much data as we can, return the amount
* still buffered.
*/
return bufchain_size(&c->v.v2.outbuffer);
}
/*
* Potentially enlarge the window on an SSH2 channel.
*/
static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
{
if (newwin > c->v.v2.locwindow) {
ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
ssh2_pkt_adduint32(c->remoteid);
ssh2_pkt_adduint32(newwin - c->v.v2.locwindow);
ssh2_pkt_send();
c->v.v2.locwindow = newwin;
}
}
@ -4047,7 +4208,8 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
ssh2_pkt_addstring("session");
ssh2_pkt_adduint32(mainchan->localid);
ssh2_pkt_adduint32(0x8000UL); /* our window size */
mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
ssh2_pkt_adduint32(mainchan->v.v2.locwindow); /* our window size */
ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
ssh2_pkt_send();
crWaitUntilV(ispkt);
@ -4063,10 +4225,9 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
mainchan->remoteid = ssh2_pkt_getuint32();
mainchan->type = CHAN_MAINSESSION;
mainchan->closes = 0;
mainchan->v2.remwindow = ssh2_pkt_getuint32();
mainchan->v2.remmaxpkt = ssh2_pkt_getuint32();
mainchan->v2.outbuffer = NULL;
mainchan->v2.outbuflen = mainchan->v2.outbufsize = 0;
mainchan->v.v2.remwindow = ssh2_pkt_getuint32();
mainchan->v.v2.remmaxpkt = ssh2_pkt_getuint32();
bufchain_init(&mainchan->v.v2.outbuffer);
add234(ssh_channels, mainchan);
logevent("Opened channel for session");
@ -4095,7 +4256,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
c->v2.remwindow += ssh2_pkt_getuint32();
c->v.v2.remwindow += ssh2_pkt_getuint32();
}
} while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
@ -4183,7 +4344,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue;/* nonexistent channel */
c->v2.remwindow += ssh2_pkt_getuint32();
c->v.v2.remwindow += ssh2_pkt_getuint32();
}
} while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
@ -4221,7 +4382,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
c->v2.remwindow += ssh2_pkt_getuint32();
c->v.v2.remwindow += ssh2_pkt_getuint32();
}
} while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
@ -4264,7 +4425,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
c->v2.remwindow += ssh2_pkt_getuint32();
c->v.v2.remwindow += ssh2_pkt_getuint32();
}
} while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
@ -4308,7 +4469,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
c->v2.remwindow += ssh2_pkt_getuint32();
c->v.v2.remwindow += ssh2_pkt_getuint32();
}
} while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
@ -4352,17 +4513,20 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
continue; /* extended but not stderr */
ssh2_pkt_getstring(&data, &length);
if (data) {
int bufsize;
c->v.v2.locwindow -= length;
switch (c->type) {
case CHAN_MAINSESSION:
bufsize =
from_backend(pktin.type ==
SSH2_MSG_CHANNEL_EXTENDED_DATA, data,
length);
SSH2_MSG_CHANNEL_EXTENDED_DATA,
data, length);
break;
case CHAN_X11:
x11_send(c->u.x11.s, data, length);
bufsize = x11_send(c->u.x11.s, data, length);
break;
case CHAN_SOCKDATA:
pfd_send(c->u.pfd.s, data, length);
bufsize = pfd_send(c->u.pfd.s, data, length);
break;
case CHAN_AGENT:
while (length > 0) {
@ -4412,17 +4576,15 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
c->u.a.lensofar = 0;
}
}
bufsize = 0;
break;
}
/*
* Enlarge the window again at the remote
* side, just in case it ever runs down and
* they fail to send us any more data.
* If we are not buffering too much data,
* enlarge the window again at the remote side.
*/
ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
ssh2_pkt_adduint32(c->remoteid);
ssh2_pkt_adduint32(length);
ssh2_pkt_send();
if (bufsize < OUR_V2_WINSIZE)
ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
}
} else if (pktin.type == SSH2_MSG_DISCONNECT) {
ssh_state = SSH_STATE_CLOSED;
@ -4475,7 +4637,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
break;
}
del234(ssh_channels, c);
sfree(c->v2.outbuffer);
bufchain_clear(&c->v.v2.outbuffer);
sfree(c);
/*
@ -4498,7 +4660,7 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
c->v2.remwindow += ssh2_pkt_getuint32();
c->v.v2.remwindow += ssh2_pkt_getuint32();
try_send = TRUE;
} else if (pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
unsigned i = ssh2_pkt_getuint32();
@ -4511,10 +4673,9 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
c->remoteid = ssh2_pkt_getuint32();
c->type = CHAN_SOCKDATA;
c->closes = 0;
c->v2.remwindow = ssh2_pkt_getuint32();
c->v2.remmaxpkt = ssh2_pkt_getuint32();
c->v2.outbuffer = NULL;
c->v2.outbuflen = c->v2.outbufsize = 0;
c->v.v2.remwindow = ssh2_pkt_getuint32();
c->v.v2.remmaxpkt = ssh2_pkt_getuint32();
bufchain_init(&c->v.v2.outbuffer);
pfd_confirm(c->u.pfd.s);
} else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) {
char *type;
@ -4588,15 +4749,15 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
} else {
c->localid = alloc_channel_id();
c->closes = 0;
c->v2.remwindow = winsize;
c->v2.remmaxpkt = pktsize;
c->v2.outbuffer = NULL;
c->v2.outbuflen = c->v2.outbufsize = 0;
c->v.v2.locwindow = OUR_V2_WINSIZE;
c->v.v2.remwindow = winsize;
c->v.v2.remmaxpkt = pktsize;
bufchain_init(&c->v.v2.outbuffer);
add234(ssh_channels, c);
ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
ssh2_pkt_adduint32(c->remoteid);
ssh2_pkt_adduint32(c->localid);
ssh2_pkt_adduint32(0x8000UL); /* our window size */
ssh2_pkt_adduint32(c->v.v2.locwindow);
ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
ssh2_pkt_send();
}
@ -4617,8 +4778,27 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
/*
* Try to send data on all channels if we can.
*/
for (i = 0; NULL != (c = index234(ssh_channels, i)); i++)
ssh2_try_send(c);
for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) {
int bufsize = ssh2_try_send(c);
if (bufsize == 0) {
switch (c->type) {
case CHAN_MAINSESSION:
/* stdin need not receive an unthrottle
* notification since it will be polled */
break;
case CHAN_X11:
x11_unthrottle(c->u.x11.s);
break;
case CHAN_AGENT:
/* agent sockets are request/response and need no
* buffer management */
break;
case CHAN_SOCKDATA:
pfd_unthrottle(c->u.pfd.s);
break;
}
}
}
}
}
@ -4652,6 +4832,8 @@ static char *ssh_init(char *host, int port, char **realhost)
ssh_send_ok = 0;
ssh_editing = 0;
ssh_echoing = 0;
ssh1_throttle_count = 0;
ssh_overall_bufsize = 0;
p = connect_to_host(host, port, realhost);
if (p != NULL)
@ -4663,12 +4845,44 @@ static char *ssh_init(char *host, int port, char **realhost)
/*
* Called to send data down the Telnet connection.
*/
static void ssh_send(char *buf, int len)
static int ssh_send(char *buf, int len)
{
if (s == NULL || ssh_protocol == NULL)
return;
return 0;
ssh_protocol(buf, len, 0);
return ssh_sendbuffer();
}
/*
* Called to query the current amount of buffered stdin data.
*/
static int ssh_sendbuffer(void)
{
int override_value;
if (s == NULL || ssh_protocol == NULL)
return 0;
/*
* If the SSH socket itself has backed up, add the total backup
* size on that to any individual buffer on the stdin channel.
*/
override_value = 0;
if (ssh_throttled_all)
override_value = ssh_overall_bufsize;
if (ssh_version == 1) {
return override_value;
} else if (ssh_version == 2) {
if (!mainchan || mainchan->closes > 0)
return override_value;
else
return override_value + bufchain_size(&mainchan->v.v2.outbuffer);
}
return 0;
}
/*
@ -4762,6 +4976,23 @@ void *new_sock_channel(Socket s)
return c;
}
/*
* This is called when stdout/stderr (the entity to which
* from_backend sends data) manages to clear some backlog.
*/
void ssh_unthrottle(int bufsize)
{
if (ssh_version == 1) {
if (bufsize < SSH1_BUFFER_LIMIT) {
ssh1_stdout_throttling = 0;
ssh1_throttle(-1);
}
} else {
if (mainchan && mainchan->closes == 0)
ssh2_set_window(mainchan, OUR_V2_WINSIZE - bufsize);
}
}
void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
{
struct ssh_channel *c = (struct ssh_channel *)channel;
@ -4781,7 +5012,8 @@ void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
ssh2_pkt_addstring("direct-tcpip");
ssh2_pkt_adduint32(c->localid);
ssh2_pkt_adduint32(0x8000UL); /* our window size */
c->v.v2.locwindow = OUR_V2_WINSIZE;
ssh2_pkt_adduint32(c->v.v2.locwindow);/* our window size */
ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
ssh2_pkt_addstring(hostname);
ssh2_pkt_adduint32(port);
@ -4820,10 +5052,12 @@ static int ssh_ldisc(int option)
Backend ssh_backend = {
ssh_init,
ssh_send,
ssh_sendbuffer,
ssh_size,
ssh_special,
ssh_socket,
ssh_sendok,
ssh_ldisc,
ssh_unthrottle,
22
};

4
ssh.h
Просмотреть файл

@ -3,6 +3,10 @@
#include "puttymem.h"
#include "network.h"
extern void sshfwd_close(struct ssh_channel *c);
extern int sshfwd_write(struct ssh_channel *c, char *, int);
extern void sshfwd_unthrottle(struct ssh_channel *c, int bufsize);
/*
* Useful thing.
*/

74
telnet.c
Просмотреть файл

@ -174,9 +174,11 @@ static struct Opt *opts[] = {
&o_we_sga, &o_they_sga, NULL
};
#define TELNET_MAX_BACKLOG 4096
static int echoing = TRUE, editing = TRUE;
static int activated = FALSE;
static int telnet_bufsize;
static int in_synch;
static int sb_opt, sb_len;
static char *sb_buf = NULL;
@ -185,8 +187,10 @@ static int sb_size = 0;
static void c_write1(int c)
{
int backlog;
char cc = (char) c;
from_backend(0, &cc, 1);
backlog = from_backend(0, &cc, 1);
sk_set_frozen(s, backlog > TELNET_MAX_BACKLOG);
}
static void log_option(char *sender, int cmd, int option)
@ -206,7 +210,7 @@ static void send_opt(int cmd, int option)
b[0] = IAC;
b[1] = cmd;
b[2] = option;
sk_write(s, b, 3);
telnet_bufsize = sk_write(s, b, 3);
log_option("client", cmd, option);
}
@ -340,7 +344,7 @@ static void process_subneg(void)
n = 4 + strlen(cfg.termspeed);
b[n] = IAC;
b[n + 1] = SE;
sk_write(s, b, n + 2);
telnet_bufsize = sk_write(s, b, n + 2);
logevent("server:\tSB TSPEED SEND");
sprintf(logbuf, "client:\tSB TSPEED IS %s", cfg.termspeed);
logevent(logbuf);
@ -361,7 +365,7 @@ static void process_subneg(void)
'a' : cfg.termtype[n]);
b[n + 4] = IAC;
b[n + 5] = SE;
sk_write(s, b, n + 6);
telnet_bufsize = sk_write(s, b, n + 6);
b[n + 4] = 0;
logevent("server:\tSB TTYPE SEND");
sprintf(logbuf, "client:\tSB TTYPE IS %s", b + 4);
@ -437,7 +441,7 @@ static void process_subneg(void)
}
b[n++] = IAC;
b[n++] = SE;
sk_write(s, b, n);
telnet_bufsize = sk_write(s, b, n);
sprintf(logbuf, "client:\tSB %s IS %s", telopt(sb_opt),
n == 6 ? "<nothing>" : "<stuff>");
logevent(logbuf);
@ -650,7 +654,7 @@ static char *telnet_init(char *host, int port, char **realhost)
/*
* Called to send data down the Telnet connection.
*/
static void telnet_send(char *buf, int len)
static int telnet_send(char *buf, int len)
{
char *p;
static unsigned char iac[2] = { IAC, IAC };
@ -660,7 +664,7 @@ static void telnet_send(char *buf, int len)
#endif
if (s == NULL)
return;
return 0;
p = buf;
while (p < buf + len) {
@ -668,13 +672,24 @@ static void telnet_send(char *buf, int len)
while (iswritable((unsigned char) *p) && p < buf + len)
p++;
sk_write(s, q, p - q);
telnet_bufsize = sk_write(s, q, p - q);
while (p < buf + len && !iswritable((unsigned char) *p)) {
telnet_bufsize =
sk_write(s, (unsigned char) *p == IAC ? iac : cr, 2);
p++;
}
}
return telnet_bufsize;
}
/*
* Called to query the current socket sendability status.
*/
static int telnet_sendbuffer(void)
{
return telnet_bufsize;
}
/*
@ -696,7 +711,7 @@ static void telnet_size(void)
b[6] = rows & 0xFF;
b[7] = IAC;
b[8] = SE;
sk_write(s, b, 9);
telnet_bufsize = sk_write(s, b, 9);
sprintf(logbuf, "client:\tSB NAWS %d,%d",
((unsigned char) b[3] << 8) + (unsigned char) b[4],
((unsigned char) b[5] << 8) + (unsigned char) b[6]);
@ -717,59 +732,59 @@ static void telnet_special(Telnet_Special code)
switch (code) {
case TS_AYT:
b[1] = AYT;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_BRK:
b[1] = BREAK;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_EC:
b[1] = EC;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_EL:
b[1] = EL;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_GA:
b[1] = GA;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_NOP:
b[1] = NOP;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_ABORT:
b[1] = ABORT;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_AO:
b[1] = AO;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_IP:
b[1] = IP;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_SUSP:
b[1] = SUSP;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_EOR:
b[1] = EOR;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_EOF:
b[1] = xEOF;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
break;
case TS_EOL:
sk_write(s, "\r\n", 2);
telnet_bufsize = sk_write(s, "\r\n", 2);
break;
case TS_SYNCH:
b[1] = DM;
sk_write(s, b, 1);
sk_write_oob(s, b + 1, 1);
telnet_bufsize = sk_write(s, b, 1);
telnet_bufsize = sk_write_oob(s, b + 1, 1);
break;
case TS_RECHO:
if (o_echo.state == INACTIVE || o_echo.state == REALLY_INACTIVE) {
@ -786,7 +801,7 @@ static void telnet_special(Telnet_Special code)
case TS_PING:
if (o_they_sga.state == ACTIVE) {
b[1] = NOP;
sk_write(s, b, 2);
telnet_bufsize = sk_write(s, b, 2);
}
break;
}
@ -802,6 +817,11 @@ static int telnet_sendok(void)
return 1;
}
static void telnet_unthrottle(int backlog)
{
sk_set_frozen(s, backlog > TELNET_MAX_BACKLOG);
}
static int telnet_ldisc(int option)
{
if (option == LD_ECHO)
@ -814,10 +834,12 @@ static int telnet_ldisc(int option)
Backend telnet_backend = {
telnet_init,
telnet_send,
telnet_sendbuffer,
telnet_size,
telnet_special,
telnet_socket,
telnet_sendok,
telnet_ldisc,
telnet_unthrottle,
23
};

22
terminal.c
Просмотреть файл

@ -3281,13 +3281,33 @@ int term_ldisc(int option)
/*
* from_backend(), to get data from the backend for the terminal.
*/
void from_backend(int is_stderr, char *data, int len)
int from_backend(int is_stderr, char *data, int len)
{
while (len--) {
if (inbuf_head >= INBUF_SIZE)
term_out();
inbuf[inbuf_head++] = *data++;
}
/*
* We process all stdout/stderr data immediately we receive it,
* and don't return until it's all gone. Therefore, there's no
* reason at all to return anything other than zero from this
* function.
*
* This is a slightly suboptimal way to deal with SSH2 - in
* principle, the window mechanism would allow us to continue
* to accept data on forwarded ports and X connections even
* while the terminal processing was going slowly - but we
* can't do the 100% right thing without moving the terminal
* processing into a separate thread, and that might hurt
* portability. So we manage stdout buffering the old SSH1 way:
* if the terminal processing goes slowly, the whole SSH
* connection stops accepting data until it's ready.
*
* In practice, I can't imagine this causing serious trouble.
*/
return 0;
}
/*

17
window.c
Просмотреть файл

@ -1863,6 +1863,14 @@ static LRESULT CALLBACK WndProc(HWND hwnd, UINT message,
len = TranslateKey(message, wParam, lParam, buf);
if (len == -1)
return DefWindowProc(hwnd, message, wParam, lParam);
/*
* We need not bother about stdin backlogs here,
* because in GUI PuTTY we can't do anything about
* it anyway; there's no means of asking Windows to
* hold off on KEYDOWN messages. We _have_ to
* buffer everything we're sent.
*/
ldisc_send(buf, len);
if (len > 0)
@ -2998,6 +3006,15 @@ static int TranslateKey(UINT message, WPARAM wParam, LPARAM lParam,
luni_send(&keybuf, 1);
} else {
ch = (char) alt_sum;
/*
* We need not bother about stdin
* backlogs here, because in GUI PuTTY
* we can't do anything about it
* anyway; there's no means of asking
* Windows to hold off on KEYDOWN
* messages. We _have_ to buffer
* everything we're sent.
*/
ldisc_send(&ch, 1);
}
alt_sum = 0;

127
winnet.c
Просмотреть файл

@ -48,14 +48,13 @@
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#define DEFINE_PLUG_METHOD_MACROS
#include "putty.h"
#include "network.h"
#include "tree234.h"
#define BUFFER_GRANULE 512
struct Socket_tag {
struct socket_function_table *fn;
/* the above variable absolutely *must* be the first in this structure */
@ -63,9 +62,12 @@ struct Socket_tag {
SOCKET s;
Plug plug;
void *private_ptr;
struct buffer *head, *tail;
bufchain output_data;
int writable;
int frozen; /* this tells the write stuff not to even bother trying to send at this point */
int frozen; /* this causes readability notifications to be ignored */
int frozen_readable; /* this means we missed at least one readability
* notification while we were frozen */
char oobdata[1];
int sending_oob;
int oobinline;
};
@ -90,12 +92,6 @@ struct SockAddr_tag {
#endif
};
struct buffer {
struct buffer *next;
int buflen, bufpos;
char buf[BUFFER_GRANULE];
};
static tree234 *sktree;
static int cmpfortree(void *av, void *bv)
@ -365,8 +361,8 @@ static void sk_tcp_flush(Socket s)
}
static void sk_tcp_close(Socket s);
static void sk_tcp_write(Socket s, char *data, int len);
static void sk_tcp_write_oob(Socket s, char *data, int len);
static int sk_tcp_write(Socket s, char *data, int len);
static int sk_tcp_write_oob(Socket s, char *data, int len);
static char *sk_tcp_socket_error(Socket s);
extern char *do_select(SOCKET skt, int startup);
@ -393,10 +389,11 @@ Socket sk_register(void *sock, Plug plug)
ret->fn = &fn_table;
ret->error = NULL;
ret->plug = plug;
ret->head = ret->tail = NULL;
bufchain_init(&ret->output_data);
ret->writable = 1; /* to start with */
ret->sending_oob = 0;
ret->frozen = 1;
ret->frozen_readable = 0;
ret->s = (SOCKET)sock;
@ -450,10 +447,11 @@ Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
ret->fn = &fn_table;
ret->error = NULL;
ret->plug = plug;
ret->head = ret->tail = NULL;
bufchain_init(&ret->output_data);
ret->writable = 1; /* to start with */
ret->sending_oob = 0;
ret->frozen = 0;
ret->frozen_readable = 0;
/*
* Open socket.
@ -601,10 +599,11 @@ Socket sk_newlistenner(int port, Plug plug)
ret->fn = &fn_table;
ret->error = NULL;
ret->plug = plug;
ret->head = ret->tail = NULL;
bufchain_init(&ret->output_data);
ret->writable = 0; /* to start with */
ret->sending_oob = 0;
ret->frozen = 0;
ret->frozen_readable = 0;
/*
* Open socket.
@ -694,22 +693,22 @@ static void sk_tcp_close(Socket sock)
*/
void try_send(Actual_Socket s)
{
if (s->frozen) return;
while (s->head) {
while (s->sending_oob || bufchain_size(&s->output_data) > 0) {
int nsent;
DWORD err;
void *data;
int len, urgentflag;
if (s->sending_oob) {
urgentflag = MSG_OOB;
len = s->sending_oob;
data = &s->oobdata;
} else {
urgentflag = 0;
len = s->head->buflen - s->head->bufpos;
bufchain_prefix(&s->output_data, &data, &len);
}
nsent =
send(s->s, s->head->buf + s->head->bufpos, len, urgentflag);
nsent = send(s->s, data, len, urgentflag);
noise_ultralight(nsent);
if (nsent <= 0) {
err = (nsent < 0 ? WSAGetLastError() : 0);
@ -742,83 +741,48 @@ void try_send(Actual_Socket s)
fatalbox(winsock_error_string(err));
}
} else {
s->head->bufpos += nsent;
if (s->sending_oob)
s->sending_oob -= nsent;
if (s->head->bufpos >= s->head->buflen) {
struct buffer *tmp = s->head;
s->head = tmp->next;
sfree(tmp);
if (!s->head)
s->tail = NULL;
if (s->sending_oob) {
if (nsent < len) {
memmove(s->oobdata, s->oobdata+nsent, len-nsent);
s->sending_oob = len - nsent;
} else {
s->sending_oob = 0;
}
} else {
bufchain_consume(&s->output_data, nsent);
}
}
}
}
static void sk_tcp_write(Socket sock, char *buf, int len)
static int sk_tcp_write(Socket sock, char *buf, int len)
{
Actual_Socket s = (Actual_Socket) sock;
/*
* Add the data to the buffer list on the socket.
*/
if (s->tail && s->tail->buflen < BUFFER_GRANULE) {
int copylen = min(len, BUFFER_GRANULE - s->tail->buflen);
memcpy(s->tail->buf + s->tail->buflen, buf, copylen);
buf += copylen;
len -= copylen;
s->tail->buflen += copylen;
}
while (len > 0) {
int grainlen = min(len, BUFFER_GRANULE);
struct buffer *newbuf;
newbuf = smalloc(sizeof(struct buffer));
newbuf->bufpos = 0;
newbuf->buflen = grainlen;
memcpy(newbuf->buf, buf, grainlen);
buf += grainlen;
len -= grainlen;
if (s->tail)
s->tail->next = newbuf;
else
s->head = s->tail = newbuf;
newbuf->next = NULL;
s->tail = newbuf;
}
bufchain_add(&s->output_data, buf, len);
/*
* Now try sending from the start of the buffer list.
*/
if (s->writable)
try_send(s);
return bufchain_size(&s->output_data);
}
static void sk_tcp_write_oob(Socket sock, char *buf, int len)
static int sk_tcp_write_oob(Socket sock, char *buf, int len)
{
Actual_Socket s = (Actual_Socket) sock;
/*
* Replace the buffer list on the socket with the data.
*/
if (!s->head) {
s->head = smalloc(sizeof(struct buffer));
} else {
struct buffer *walk = s->head->next;
while (walk) {
struct buffer *tmp = walk;
walk = tmp->next;
sfree(tmp);
}
}
s->head->next = NULL;
s->tail = s->head;
s->head->buflen = len;
memcpy(s->head->buf, buf, len);
/*
* Set the Urgent marker.
*/
bufchain_clear(&s->output_data);
assert(len <= sizeof(s->oobdata));
memcpy(s->oobdata, buf, len);
s->sending_oob = len;
/*
@ -826,6 +790,8 @@ static void sk_tcp_write_oob(Socket sock, char *buf, int len)
*/
if (s->writable)
try_send(s);
return s->sending_oob;
}
int select_result(WPARAM wParam, LPARAM lParam)
@ -853,10 +819,11 @@ int select_result(WPARAM wParam, LPARAM lParam)
switch (WSAGETSELECTEVENT(lParam)) {
case FD_READ:
/* In the case the socket is still frozen, we don't even bother */
if (s->frozen)
if (s->frozen) {
s->frozen_readable = 1;
break;
}
/*
* We have received data on the socket. For an oobinline
@ -911,8 +878,15 @@ int select_result(WPARAM wParam, LPARAM lParam)
}
break;
case FD_WRITE:
{
int bufsize_before, bufsize_after;
s->writable = 1;
bufsize_before = s->sending_oob + bufchain_size(&s->output_data);
try_send(s);
bufsize_after = s->sending_oob + bufchain_size(&s->output_data);
if (bufsize_after < bufsize_before)
plug_sent(s->plug, bufsize_after);
}
break;
case FD_CLOSE:
/* Signal a close on the socket. First read any outstanding data. */
@ -992,11 +966,14 @@ static char *sk_tcp_socket_error(Socket sock)
void sk_set_frozen(Socket sock, int is_frozen)
{
Actual_Socket s = (Actual_Socket) sock;
if (s->frozen == is_frozen)
return;
s->frozen = is_frozen;
if (!is_frozen) {
if (!is_frozen && s->frozen_readable) {
char c;
recv(s->s, &c, 1, MSG_PEEK);
}
s->frozen_readable = 0;
}
/*

56
x11fwd.c
Просмотреть файл

@ -58,9 +58,6 @@
#define PUT_16BIT(endian, cp, val) \
(endian=='B' ? PUT_16BIT_MSB_FIRST(cp, val) : PUT_16BIT_LSB_FIRST(cp, val))
extern void sshfwd_close(void *);
extern void sshfwd_write(void *, char *, int);
struct X11Private {
struct plug_function_table *fn;
/* the above variable absolutely *must* be the first in this structure */
@ -69,6 +66,7 @@ struct X11Private {
unsigned char *auth_data;
int data_read, auth_plen, auth_psize, auth_dlen, auth_dsize;
int verified;
int throttled, throttle_override;
void *c; /* data used by ssh.c */
Socket s;
};
@ -127,10 +125,21 @@ static int x11_receive(Plug plug, int urgent, char *data, int len)
{
struct X11Private *pr = (struct X11Private *) plug;
sshfwd_write(pr->c, data, len);
if (sshfwd_write(pr->c, data, len) > 0) {
pr->throttled = 1;
sk_set_frozen(pr->s, 1);
}
return 1;
}
static void x11_sent(Plug plug, int bufsize)
{
struct X11Private *pr = (struct X11Private *) plug;
sshfwd_unthrottle(pr->c, bufsize);
}
/*
* Called to set up the raw connection.
*
@ -141,7 +150,9 @@ char *x11_init(Socket * s, char *display, void *c)
{
static struct plug_function_table fn_table = {
x11_closing,
x11_receive
x11_receive,
x11_sent,
NULL
};
SockAddr addr;
@ -181,6 +192,7 @@ char *x11_init(Socket * s, char *display, void *c)
pr->auth_protocol = NULL;
pr->verified = 0;
pr->data_read = 0;
pr->throttled = pr->throttle_override = 0;
pr->c = c;
pr->s = *s = sk_new(addr, port, 0, 1, (Plug) pr);
@ -210,15 +222,37 @@ void x11_close(Socket s)
sk_close(s);
}
void x11_unthrottle(Socket s)
{
struct X11Private *pr;
if (!s)
return;
pr = (struct X11Private *) sk_get_private_ptr(s);
pr->throttled = 0;
sk_set_frozen(s, pr->throttled || pr->throttle_override);
}
void x11_override_throttle(Socket s, int enable)
{
struct X11Private *pr;
if (!s)
return;
pr = (struct X11Private *) sk_get_private_ptr(s);
pr->throttle_override = enable;
sk_set_frozen(s, pr->throttled || pr->throttle_override);
}
/*
* Called to send data down the raw connection.
*/
void x11_send(Socket s, char *data, int len)
int x11_send(Socket s, char *data, int len)
{
struct X11Private *pr = (struct X11Private *) sk_get_private_ptr(s);
if (s == NULL)
return;
return 0;
/*
* Read the first packet.
@ -226,7 +260,7 @@ void x11_send(Socket s, char *data, int len)
while (len > 0 && pr->data_read < 12)
pr->firstpkt[pr->data_read++] = (unsigned char) (len--, *data++);
if (pr->data_read < 12)
return;
return 0;
/*
* If we have not allocated the auth_protocol and auth_data
@ -251,7 +285,7 @@ void x11_send(Socket s, char *data, int len)
pr->auth_data[pr->data_read++ - 12 -
pr->auth_psize] = (unsigned char) (len--, *data++);
if (pr->data_read < 12 + pr->auth_psize + pr->auth_dsize)
return;
return 0;
/*
* If we haven't verified the authentication, do so now.
@ -280,7 +314,7 @@ void x11_send(Socket s, char *data, int len)
sshfwd_write(pr->c, reply, 8 + msgsize);
sshfwd_close(pr->c);
x11_close(s);
return;
return 0;
}
/*
@ -298,5 +332,5 @@ void x11_send(Socket s, char *data, int len)
* After initialisation, just copy data simply.
*/
sk_write(s, data, len);
return sk_write(s, data, len);
}