int
sftp_server_main(int argc, char **argv, struct passwd *user_pw)
{
fd_set *rset, *wset;
int i, r, in, out, max, ch, skipargs = 0, log_stderr = 0;
ssize_t len, olen, set_size;
SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
char *cp, *homedir = NULL, buf[4*4096];
long mask;
extern char *optarg;
extern char *__progname;
ssh_malloc_init(); /* must be called before any mallocs */
__progname = ssh_get_progname(argv[0]);
log_init(__progname, log_level, log_facility, log_stderr);
pw = pwcopy(user_pw);
while (!skipargs && (ch = getopt(argc, argv,
"d:f:l:P:p:Q:u:cehR")) != -1) {
switch (ch) {
case 'Q':
if (strcasecmp(optarg, "requests") != 0) {
fprintf(stderr, "Invalid query type\n");
exit(1);
}
for (i = 0; handlers[i].handler != NULL; i++)
printf("%s\n", handlers[i].name);
for (i = 0; extended_handlers[i].handler != NULL; i++)
printf("%s\n", extended_handlers[i].name);
exit(0);
break;
case 'R':
readonly = 1;
break;
case 'c':
/*
* Ignore all arguments if we are invoked as a
* shell using "sftp-server -c command"
*/
skipargs = 1;
break;
case 'e':
log_stderr = 1;
break;
case 'l':
log_level = log_level_number(optarg);
if (log_level == SYSLOG_LEVEL_NOT_SET)
error("Invalid log level \"%s\"", optarg);
break;
case 'f':
log_facility = log_facility_number(optarg);
if (log_facility == SYSLOG_FACILITY_NOT_SET)
error("Invalid log facility \"%s\"", optarg);
break;
case 'd':
cp = tilde_expand_filename(optarg, user_pw->pw_uid);
homedir = percent_expand(cp, "d", user_pw->pw_dir,
"u", user_pw->pw_name, (char *)NULL);
free(cp);
break;
case 'p':
if (request_whitelist != NULL)
fatal("Permitted requests already set");
request_whitelist = xstrdup(optarg);
break;
case 'P':
if (request_blacklist != NULL)
fatal("Refused requests already set");
request_blacklist = xstrdup(optarg);
break;
case 'u':
errno = 0;
mask = strtol(optarg, &cp, 8);
if (mask < 0 || mask > 0777 || *cp != '\0' ||
cp == optarg || (mask == 0 && errno != 0))
fatal("Invalid umask \"%s\"", optarg);
(void)umask((mode_t)mask);
break;
case 'h':
default:
sftp_server_usage();
}
}
log_init(__progname, log_level, log_facility, log_stderr);
#if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE)
/*
* On Linux, we should try to avoid making /proc/self/{mem,maps}
* available to the user so that sftp access doesn't automatically
* imply arbitrary code execution access that will break
* restricted configurations.
*/
if (prctl(PR_SET_DUMPABLE, 0) != 0)
fatal("unable to make the process undumpable");
#endif /* defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE) */
/* Drop any fine-grained privileges we don't need */
platform_pledge_sftp_server();
if ((cp = getenv("SSH_CONNECTION")) != NULL) {
client_addr = xstrdup(cp);
if ((cp = strchr(client_addr, ' ')) == NULL) {
error("Malformed SSH_CONNECTION variable: \"%s\"",
getenv("SSH_CONNECTION"));
sftp_server_cleanup_exit(255);
}
*cp = '\0';
} else
client_addr = xstrdup("UNKNOWN");
logit("session opened for local user %s from [%s]",
pw->pw_name, client_addr);
in = STDIN_FILENO;
out = STDOUT_FILENO;
#ifdef HAVE_CYGWIN
setmode(in, O_BINARY);
setmode(out, O_BINARY);
#endif
max = 0;
if (in > max)
max = in;
if (out > max)
max = out;
if ((iqueue = sshbuf_new()) == NULL)
fatal("%s: sshbuf_new failed", __func__);
if ((oqueue = sshbuf_new()) == NULL)
fatal("%s: sshbuf_new failed", __func__);
rset = xcalloc(howmany(max + 1, NFDBITS), sizeof(fd_mask));
wset = xcalloc(howmany(max + 1, NFDBITS), sizeof(fd_mask));
if (homedir != NULL) {
if (chdir(homedir) != 0) {
error("chdir to \"%s\" failed: %s", homedir,
strerror(errno));
}
}
set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask);
for (;;) {
memset(rset, 0, set_size);
memset(wset, 0, set_size);
/*
* Ensure that we can read a full buffer and handle
* the worst-case length packet it can generate,
* otherwise apply backpressure by stopping reads.
*/
if ((r = sshbuf_check_reserve(iqueue, sizeof(buf))) == 0 &&
(r = sshbuf_check_reserve(oqueue,
SFTP_MAX_MSG_LENGTH)) == 0)
FD_SET(in, rset);
else if (r != SSH_ERR_NO_BUFFER_SPACE)
fatal("%s: sshbuf_check_reserve failed: %s",
__func__, ssh_err(r));
olen = sshbuf_len(oqueue);
if (olen > 0)
FD_SET(out, wset);
if (select(max+1, rset, wset, NULL, NULL) < 0) {
if (errno == EINTR)
continue;
error("select: %s", strerror(errno));
sftp_server_cleanup_exit(2);
}
/* copy stdin to iqueue */
if (FD_ISSET(in, rset)) {
len = read(in, buf, sizeof buf);
if (len == 0) {
debug("read eof");
sftp_server_cleanup_exit(0);
} else if (len < 0) {
error("read: %s", strerror(errno));
sftp_server_cleanup_exit(1);
} else if ((r = sshbuf_put(iqueue, buf, len)) != 0) {
fatal("%s: buffer error: %s",
__func__, ssh_err(r));
}
}
/* send oqueue to stdout */
if (FD_ISSET(out, wset)) {
len = write(out, sshbuf_ptr(oqueue), olen);
if (len < 0) {
error("write: %s", strerror(errno));
sftp_server_cleanup_exit(1);
} else if ((r = sshbuf_consume(oqueue, len)) != 0) {
fatal("%s: buffer error: %s",
__func__, ssh_err(r));
}
}
/*
* Process requests from client if we can fit the results
* into the output buffer, otherwise stop processing input
* and let the output queue drain.
*/
r = sshbuf_check_reserve(oqueue, SFTP_MAX_MSG_LENGTH);
if (r == 0)
process();
else if (r != SSH_ERR_NO_BUFFER_SPACE)
fatal("%s: sshbuf_check_reserve: %s",
__func__, ssh_err(r));
}
}
void
cleanup_exit(int i)
{
sftp_server_cleanup_exit(i);
}
int
sftp_server_main(int argc, char **argv, struct passwd *user_pw)
{
fd_set *rset, *wset;
int in, out, max, ch, skipargs = 0, log_stderr = 0;
ssize_t len, olen, set_size;
SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
char *cp, buf[4*4096];
const char *errmsg;
mode_t mask;
extern char *optarg;
extern char *__progname;
__progname = ssh_get_progname(argv[0]);
log_init(__progname, log_level, log_facility, log_stderr);
fake_permissions = 0;
while (!skipargs && (ch = getopt(argc, argv, "f:l:u:cehRU")) != -1) {
switch (ch) {
case 'R':
readonly = 1;
break;
case 'c':
/*
* Ignore all arguments if we are invoked as a
* shell using "sftp-server -c command"
*/
skipargs = 1;
break;
case 'e':
log_stderr = 1;
break;
case 'l':
log_level = log_level_number(optarg);
if (log_level == SYSLOG_LEVEL_NOT_SET)
error("Invalid log level \"%s\"", optarg);
break;
case 'f':
log_facility = log_facility_number(optarg);
if (log_facility == SYSLOG_FACILITY_NOT_SET)
error("Invalid log facility \"%s\"", optarg);
break;
case 'u':
mask = (mode_t)strtonum(optarg, 0, 0777, &errmsg);
if (errmsg != NULL)
fatal("Invalid umask \"%s\": %s",
optarg, errmsg);
(void)umask(mask);
break;
case 'U': /* Fake permissions */
fake_permissions = 1;
break;
case 'h':
default:
sftp_server_usage();
}
}
log_init(__progname, log_level, log_facility, log_stderr);
if ((cp = getenv("SSH_CONNECTION")) != NULL) {
client_addr = xstrdup(cp);
if ((cp = strchr(client_addr, ' ')) == NULL) {
error("Malformed SSH_CONNECTION variable: \"%s\"",
getenv("SSH_CONNECTION"));
sftp_server_cleanup_exit(255);
}
*cp = '\0';
} else
client_addr = xstrdup("UNKNOWN");
pw = pwcopy(user_pw);
logit("session opened for local user %s from [%s]",
pw->pw_name, client_addr);
in = STDIN_FILENO;
out = STDOUT_FILENO;
#ifdef HAVE_CYGWIN
setmode(in, O_BINARY);
setmode(out, O_BINARY);
#endif
max = 0;
if (in > max)
max = in;
if (out > max)
max = out;
buffer_init(&iqueue);
buffer_init(&oqueue);
set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask);
rset = (fd_set *)xmalloc(set_size);
wset = (fd_set *)xmalloc(set_size);
for (;;) {
memset(rset, 0, set_size);
memset(wset, 0, set_size);
/*
* Ensure that we can read a full buffer and handle
* the worst-case length packet it can generate,
* otherwise apply backpressure by stopping reads.
*/
if (buffer_check_alloc(&iqueue, sizeof(buf)) &&
buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH))
FD_SET(in, rset);
olen = buffer_len(&oqueue);
if (olen > 0)
FD_SET(out, wset);
if (select(max+1, rset, wset, NULL, NULL) < 0) {
if (errno == EINTR)
continue;
error("select: %s", strerror(errno));
sftp_server_cleanup_exit(2);
}
/* copy stdin to iqueue */
if (FD_ISSET(in, rset)) {
len = read(in, buf, sizeof buf);
if (len == 0) {
debug("read eof");
sftp_server_cleanup_exit(0);
} else if (len < 0) {
error("read: %s", strerror(errno));
sftp_server_cleanup_exit(1);
} else {
buffer_append(&iqueue, buf, len);
}
}
/* send oqueue to stdout */
if (FD_ISSET(out, wset)) {
len = write(out, buffer_ptr(&oqueue), olen);
if (len < 0) {
error("write: %s", strerror(errno));
sftp_server_cleanup_exit(1);
} else {
buffer_consume(&oqueue, len);
}
}
/*
* Process requests from client if we can fit the results
* into the output buffer, otherwise stop processing input
* and let the output queue drain.
*/
if (buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH))
process();
}
}
static void
process(void)
{
u_int msg_len;
u_int buf_len;
u_int consumed;
u_char type;
const u_char *cp;
int i, r;
u_int32_t id;
buf_len = sshbuf_len(iqueue);
if (buf_len < 5)
return; /* Incomplete message. */
cp = sshbuf_ptr(iqueue);
msg_len = get_u32(cp);
if (msg_len > SFTP_MAX_MSG_LENGTH) {
error("bad message from %s local user %s",
client_addr, pw->pw_name);
sftp_server_cleanup_exit(11);
}
if (buf_len < msg_len + 4)
return;
if ((r = sshbuf_consume(iqueue, 4)) != 0)
fatal("%s: buffer error: %s", __func__, ssh_err(r));
buf_len -= 4;
if ((r = sshbuf_get_u8(iqueue, &type)) != 0)
fatal("%s: buffer error: %s", __func__, ssh_err(r));
switch (type) {
case SSH2_FXP_INIT:
process_init();
init_done = 1;
break;
case SSH2_FXP_EXTENDED:
if (!init_done)
fatal("Received extended request before init");
if ((r = sshbuf_get_u32(iqueue, &id)) != 0)
fatal("%s: buffer error: %s", __func__, ssh_err(r));
process_extended(id);
break;
default:
if (!init_done)
fatal("Received %u request before init", type);
if ((r = sshbuf_get_u32(iqueue, &id)) != 0)
fatal("%s: buffer error: %s", __func__, ssh_err(r));
for (i = 0; handlers[i].handler != NULL; i++) {
if (type == handlers[i].type) {
if (!request_permitted(&handlers[i])) {
send_status(id,
SSH2_FX_PERMISSION_DENIED);
} else {
handlers[i].handler(id);
}
break;
}
}
if (handlers[i].handler == NULL)
error("Unknown message %u", type);
}
/* discard the remaining bytes from the current packet */
if (buf_len < sshbuf_len(iqueue)) {
error("iqueue grew unexpectedly");
sftp_server_cleanup_exit(255);
}
consumed = buf_len - sshbuf_len(iqueue);
if (msg_len < consumed) {
error("msg_len %u < consumed %u", msg_len, consumed);
sftp_server_cleanup_exit(255);
}
if (msg_len > consumed &&
(r = sshbuf_consume(iqueue, msg_len - consumed)) != 0)
fatal("%s: buffer error: %s", __func__, ssh_err(r));
}
static void
process(void)
{
u_int msg_len;
u_int buf_len;
u_int consumed;
u_int type;
u_char *cp;
buf_len = buffer_len(&iqueue);
if (buf_len < 5)
return; /* Incomplete message. */
cp = buffer_ptr(&iqueue);
msg_len = get_u32(cp);
if (msg_len > SFTP_MAX_MSG_LENGTH) {
error("bad message from %s local user %s",
client_addr, pw->pw_name);
sftp_server_cleanup_exit(11);
}
if (buf_len < msg_len + 4)
return;
buffer_consume(&iqueue, 4);
buf_len -= 4;
type = buffer_get_char(&iqueue);
switch (type) {
case SSH2_FXP_INIT:
process_init();
break;
case SSH2_FXP_OPEN:
process_open();
break;
case SSH2_FXP_CLOSE:
process_close();
break;
case SSH2_FXP_READ:
process_read();
break;
case SSH2_FXP_WRITE:
process_write();
break;
case SSH2_FXP_LSTAT:
process_lstat();
break;
case SSH2_FXP_FSTAT:
process_fstat();
break;
case SSH2_FXP_SETSTAT:
process_setstat();
break;
case SSH2_FXP_FSETSTAT:
process_fsetstat();
break;
case SSH2_FXP_OPENDIR:
process_opendir();
break;
case SSH2_FXP_READDIR:
process_readdir();
break;
case SSH2_FXP_REMOVE:
process_remove();
break;
case SSH2_FXP_MKDIR:
process_mkdir();
break;
case SSH2_FXP_RMDIR:
process_rmdir();
break;
case SSH2_FXP_REALPATH:
process_realpath();
break;
case SSH2_FXP_STAT:
process_stat();
break;
case SSH2_FXP_RENAME:
process_rename();
break;
case SSH2_FXP_READLINK:
process_readlink();
break;
case SSH2_FXP_SYMLINK:
process_symlink();
break;
case SSH2_FXP_EXTENDED:
process_extended();
break;
default:
error("Unknown message %d", type);
break;
}
/* discard the remaining bytes from the current packet */
if (buf_len < buffer_len(&iqueue)) {
error("iqueue grew unexpectedly");
sftp_server_cleanup_exit(255);
}
consumed = buf_len - buffer_len(&iqueue);
if (msg_len < consumed) {
error("msg_len %d < consumed %d", msg_len, consumed);
sftp_server_cleanup_exit(255);
}
if (msg_len > consumed)
buffer_consume(&iqueue, msg_len - consumed);
}
// Open or create
void SFTP::process_open(void)
{
u_int32_t id, pflags;
Attrib a;
char *utf8_name = 0;
int status = SSH2_FX_FAILURE;
try
{
id = get_int();
utf8_name = (char*) get_string(NULL);
pflags = get_int(); /* portable flags */
debug3("request %u: open flags %d", id, pflags);
#ifdef _DEBUG
if (strcmp (utf8_name, "/2stop_sftp_subsystem") == 0)
sftp_server_cleanup_exit (0);
#endif
a = get_attrib(this->iqueue);
//mode = (a.flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? a->perm : 0666; //FIXME
logit("open \"%s\" flags %s mode 0%o", //FIXME UNICODE
utf8_name, string_from_portable(pflags), 0/*mode*/);
DWORD creationDisposition = 0;
if (pflags & SSH2_FXF_CREAT)
{
if (pflags & SSH2_FXF_EXCL)
creationDisposition = CREATE_NEW;
else if (pflags & SSH2_FXF_TRUNC)
creationDisposition = CREATE_ALWAYS;
else
creationDisposition = OPEN_ALWAYS;
}
else
{
creationDisposition = OPEN_EXISTING;
}
const SFTPFilePath path = pathFact.create_path (utf8_name);
HANDLE fh = ::CreateFileW
(path.get_for_call ().c_str (),
flags_from_portable (pflags),
FILE_SHARE_READ,
NULL, //FIXME ACL
creationDisposition,
//names in different registry are different //UT
FILE_ATTRIBUTE_NORMAL,
// TODO make performance experiments with FILE_FLAG_RANDOM_ACCESS ,
// FILE_FLAG_SEQUENTIAL_SCAN
NULL
);
if (fh == INVALID_HANDLE_VALUE)
{
status = errno_to_portable(::GetLastError ());
} else {
int handle = handle_new(HANDLE_FILE, path, fh, NULL);
debug ("%s is opened as handle %d",
utf8_name, (int) handle);
if (handle < 0) {
(void) ::CloseHandle (fh);
} else {
send_handle(id, handle);
status = SSH2_FX_OK;
}
}
}
#ifdef _DEBUG
catch (::XShuttingDown&)
{
throw;
}
#endif
catch (Path::InvalidPath&)
{
//logit
status = SSH2_FX_FAILURE;
// TODO return the reason
}
catch (...)
{
status = SSH2_FX_FAILURE;
error ("unhandled exception in %s", __FUNCTION__);
}
if (status != SSH2_FX_OK)
send_status(id, status);
if (utf8_name) xfree(utf8_name);
}
void SFTP::process(void)
{
const u_int msg_len = buffer_get_int (&iqueue);
const u_int type = buffer_get_char(&iqueue);
switch (type) {
case SSH2_FXP_INIT:
process_init();
break;
case SSH2_FXP_OPEN:
process_open();
break;
case SSH2_FXP_CLOSE:
process_close();
break;
case SSH2_FXP_READ:
process_read();
break;
case SSH2_FXP_WRITE:
process_write();
break;
case SSH2_FXP_LSTAT:
process_lstat();
break;
case SSH2_FXP_FSTAT:
process_fstat();
break;
case SSH2_FXP_SETSTAT:
process_setstat();
break;
case SSH2_FXP_FSETSTAT:
process_fsetstat();
break;
case SSH2_FXP_OPENDIR:
process_opendir();
break;
case SSH2_FXP_READDIR:
process_readdir();
break;
case SSH2_FXP_REMOVE:
process_remove();
break;
case SSH2_FXP_MKDIR:
process_mkdir();
break;
case SSH2_FXP_RMDIR:
process_rmdir();
break;
case SSH2_FXP_REALPATH:
process_realpath();
break;
case SSH2_FXP_STAT:
process_stat();
break;
case SSH2_FXP_RENAME:
process_rename();
break;
case SSH2_FXP_READLINK:
process_readlink();
break;
case SSH2_FXP_SYMLINK:
process_symlink();
break;
case SSH2_FXP_EXTENDED:
process_extended();
break;
default:
error("Unknown message %d", type);
break;
}
/* discard the remaining bytes from the current packet */
if (msg_len < buffer_len(&iqueue)) {
error("iqueue grew unexpectedly");
sftp_server_cleanup_exit(255);
}
u_int consumed = msg_len - buffer_len(&iqueue);
if (msg_len < consumed) {
error("msg_len %d < consumed %d", msg_len, consumed);
sftp_server_cleanup_exit(255);
}
if (msg_len > consumed)
buffer_consume(&iqueue, msg_len - consumed);
}
int
sftp_server_main(int argc, char **argv, struct passwd *user_pw)
{
fd_set *rset, *wset;
int i, in, out, max, ch, skipargs = 0, log_stderr = 0;
ssize_t len, olen, set_size;
SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
char *cp, *homedir = NULL, buf[4*4096];
long mask;
extern char *optarg;
extern char *__progname;
__progname = ssh_get_progname(argv[0]);
log_init(__progname, log_level, log_facility, log_stderr);
pw = pwcopy(user_pw);
while (!skipargs && (ch = getopt(argc, argv,
"d:f:l:P:p:Q:u:cehR")) != -1) {
switch (ch) {
case 'Q':
if (strcasecmp(optarg, "requests") != 0) {
fprintf(stderr, "Invalid query type\n");
exit(1);
}
for (i = 0; handlers[i].handler != NULL; i++)
printf("%s\n", handlers[i].name);
for (i = 0; extended_handlers[i].handler != NULL; i++)
printf("%s\n", extended_handlers[i].name);
exit(0);
break;
case 'R':
readonly = 1;
break;
case 'c':
/*
* Ignore all arguments if we are invoked as a
* shell using "sftp-server -c command"
*/
skipargs = 1;
break;
case 'e':
log_stderr = 1;
break;
case 'l':
log_level = log_level_number(optarg);
if (log_level == SYSLOG_LEVEL_NOT_SET)
error("Invalid log level \"%s\"", optarg);
break;
case 'f':
log_facility = log_facility_number(optarg);
if (log_facility == SYSLOG_FACILITY_NOT_SET)
error("Invalid log facility \"%s\"", optarg);
break;
case 'd':
cp = tilde_expand_filename(optarg, user_pw->pw_uid);
homedir = percent_expand(cp, "d", user_pw->pw_dir,
"u", user_pw->pw_name, (char *)NULL);
free(cp);
break;
case 'p':
if (request_whitelist != NULL)
fatal("Permitted requests already set");
request_whitelist = xstrdup(optarg);
break;
case 'P':
if (request_blacklist != NULL)
fatal("Refused requests already set");
request_blacklist = xstrdup(optarg);
break;
case 'u':
errno = 0;
mask = strtol(optarg, &cp, 8);
if (mask < 0 || mask > 0777 || *cp != '\0' ||
cp == optarg || (mask == 0 && errno != 0))
fatal("Invalid umask \"%s\"", optarg);
(void)umask((mode_t)mask);
break;
case 'h':
default:
sftp_server_usage();
}
}
log_init(__progname, log_level, log_facility, log_stderr);
if ((cp = getenv("SSH_CONNECTION")) != NULL) {
client_addr = xstrdup(cp);
if ((cp = strchr(client_addr, ' ')) == NULL) {
error("Malformed SSH_CONNECTION variable: \"%s\"",
getenv("SSH_CONNECTION"));
sftp_server_cleanup_exit(255);
}
*cp = '\0';
} else
client_addr = xstrdup("UNKNOWN");
logit("session opened for local user %s from [%s]",
pw->pw_name, client_addr);
in = STDIN_FILENO;
out = STDOUT_FILENO;
#ifdef HAVE_CYGWIN
setmode(in, O_BINARY);
setmode(out, O_BINARY);
#endif
max = 0;
if (in > max)
max = in;
if (out > max)
max = out;
buffer_init(&iqueue);
buffer_init(&oqueue);
set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask);
rset = (fd_set *)xmalloc(set_size);
wset = (fd_set *)xmalloc(set_size);
if (homedir != NULL) {
if (chdir(homedir) != 0) {
error("chdir to \"%s\" failed: %s", homedir,
strerror(errno));
}
}
#ifdef NERSC_MOD
char* t1buf = encode_string(pw->pw_name, strlen(pw->pw_name));
s_audit("sftp_process_init_3", "count=%i int=%d uristring=%s addr=%s",
get_client_session_id(), (int)getppid(), t1buf, client_addr);
free(t1buf);
#endif
for (;;) {
memset(rset, 0, set_size);
memset(wset, 0, set_size);
/*
* Ensure that we can read a full buffer and handle
* the worst-case length packet it can generate,
* otherwise apply backpressure by stopping reads.
*/
if (buffer_check_alloc(&iqueue, sizeof(buf)) &&
buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH))
FD_SET(in, rset);
olen = buffer_len(&oqueue);
if (olen > 0)
FD_SET(out, wset);
if (select(max+1, rset, wset, NULL, NULL) < 0) {
if (errno == EINTR)
continue;
error("select: %s", strerror(errno));
sftp_server_cleanup_exit(2);
}
/* copy stdin to iqueue */
if (FD_ISSET(in, rset)) {
len = read(in, buf, sizeof buf);
if (len == 0) {
debug("read eof");
sftp_server_cleanup_exit(0);
} else if (len < 0) {
error("read: %s", strerror(errno));
sftp_server_cleanup_exit(1);
} else {
buffer_append(&iqueue, buf, len);
}
}
/* send oqueue to stdout */
if (FD_ISSET(out, wset)) {
len = write(out, buffer_ptr(&oqueue), olen);
if (len < 0) {
error("write: %s", strerror(errno));
sftp_server_cleanup_exit(1);
} else {
buffer_consume(&oqueue, len);
}
}
/*
* Process requests from client if we can fit the results
* into the output buffer, otherwise stop processing input
* and let the output queue drain.
*/
if (buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH))
process();
}
}
static void
process(void)
{
u_int msg_len, buf_len, consumed, type, i;
u_char *cp;
u_int32_t id;
buf_len = buffer_len(&iqueue);
if (buf_len < 5)
return; /* Incomplete message. */
cp = buffer_ptr(&iqueue);
msg_len = get_u32(cp);
if (msg_len > SFTP_MAX_MSG_LENGTH) {
error("bad message from %s local user %s",
client_addr, pw->pw_name);
sftp_server_cleanup_exit(11);
}
if (buf_len < msg_len + 4)
return;
buffer_consume(&iqueue, 4);
buf_len -= 4;
type = buffer_get_char(&iqueue);
switch (type) {
case SSH2_FXP_INIT:
process_init();
init_done = 1;
break;
case SSH2_FXP_EXTENDED:
if (!init_done)
fatal("Received extended request before init");
id = get_int();
process_extended(id);
break;
default:
if (!init_done)
fatal("Received %u request before init", type);
id = get_int();
for (i = 0; handlers[i].handler != NULL; i++) {
if (type == handlers[i].type) {
if (!request_permitted(&handlers[i])) {
send_status(id,
SSH2_FX_PERMISSION_DENIED);
} else {
handlers[i].handler(id);
}
break;
}
}
if (handlers[i].handler == NULL)
#ifdef NERSC_MOD
{
s_audit("sftp_process_unknown_3", "count=%i int=%d uristring=%d",
get_client_session_id(), (int)getppid(), type);
#endif
error("Unknown message %u", type);
#ifdef NERSC_MOD
}
#endif
}
/* discard the remaining bytes from the current packet */
if (buf_len < buffer_len(&iqueue)) {
error("iqueue grew unexpectedly");
sftp_server_cleanup_exit(255);
}
consumed = buf_len - buffer_len(&iqueue);
if (msg_len < consumed) {
error("msg_len %u < consumed %u", msg_len, consumed);
sftp_server_cleanup_exit(255);
}
if (msg_len > consumed)
buffer_consume(&iqueue, msg_len - consumed);
}
