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sftp-server.c
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/* $OpenBSD: sftp-server.c,v 1.148 2024/04/30 06:23:51 djm Exp $ */
/*
* Copyright (c) 2000-2004 Markus Friedl. All rights reserved.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "includes.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/resource.h>
#ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
#endif
#ifdef HAVE_SYS_MOUNT_H
#include <sys/mount.h>
#endif
#ifdef HAVE_SYS_STATVFS_H
#include <sys/statvfs.h>
#endif
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#ifdef HAVE_POLL_H
#include <poll.h>
#endif
#include <pwd.h>
#include <grp.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <stdarg.h>
#include "atomicio.h"
#include "xmalloc.h"
#include "sshbuf.h"
#include "ssherr.h"
#include "log.h"
#include "misc.h"
#include "match.h"
#include "uidswap.h"
#include "sftp.h"
#include "sftp-common.h"
char *sftp_realpath(const char *, char *); /* sftp-realpath.c */
/* Maximum data read that we are willing to accept */
#define SFTP_MAX_READ_LENGTH (SFTP_MAX_MSG_LENGTH - 1024)
/* Our verbosity */
static LogLevel log_level = SYSLOG_LEVEL_ERROR;
/* Our client */
static struct passwd *pw = NULL;
static char *client_addr = NULL;
/* input and output queue */
struct sshbuf *iqueue;
struct sshbuf *oqueue;
/* Version of client */
static u_int version;
/* SSH2_FXP_INIT received */
static int init_done;
/* Disable writes */
static int readonly;
/* Requests that are allowed/denied */
static char *request_allowlist, *request_denylist;
/* portable attributes, etc. */
typedef struct Stat Stat;
struct Stat {
char *name;
char *long_name;
Attrib attrib;
};
/* Packet handlers */
static void process_open(u_int32_t id);
static void process_close(u_int32_t id);
static void process_read(u_int32_t id);
static void process_write(u_int32_t id);
static void process_stat(u_int32_t id);
static void process_lstat(u_int32_t id);
static void process_fstat(u_int32_t id);
static void process_setstat(u_int32_t id);
static void process_fsetstat(u_int32_t id);
static void process_opendir(u_int32_t id);
static void process_readdir(u_int32_t id);
static void process_remove(u_int32_t id);
static void process_mkdir(u_int32_t id);
static void process_rmdir(u_int32_t id);
static void process_realpath(u_int32_t id);
static void process_rename(u_int32_t id);
static void process_readlink(u_int32_t id);
static void process_symlink(u_int32_t id);
static void process_extended_posix_rename(u_int32_t id);
static void process_extended_statvfs(u_int32_t id);
static void process_extended_fstatvfs(u_int32_t id);
static void process_extended_hardlink(u_int32_t id);
static void process_extended_fsync(u_int32_t id);
static void process_extended_lsetstat(u_int32_t id);
static void process_extended_limits(u_int32_t id);
static void process_extended_expand(u_int32_t id);
static void process_extended_copy_data(u_int32_t id);
static void process_extended_home_directory(u_int32_t id);
static void process_extended_get_users_groups_by_id(u_int32_t id);
static void process_extended(u_int32_t id);
struct sftp_handler {
const char *name; /* user-visible name for fine-grained perms */
const char *ext_name; /* extended request name */
u_int type; /* packet type, for non extended packets */
void (*handler)(u_int32_t);
int does_write; /* if nonzero, banned for readonly mode */
};
static const struct sftp_handler handlers[] = {
/* NB. SSH2_FXP_OPEN does the readonly check in the handler itself */
{ "open", NULL, SSH2_FXP_OPEN, process_open, 0 },
{ "close", NULL, SSH2_FXP_CLOSE, process_close, 0 },
{ "read", NULL, SSH2_FXP_READ, process_read, 0 },
{ "write", NULL, SSH2_FXP_WRITE, process_write, 1 },
{ "lstat", NULL, SSH2_FXP_LSTAT, process_lstat, 0 },
{ "fstat", NULL, SSH2_FXP_FSTAT, process_fstat, 0 },
{ "setstat", NULL, SSH2_FXP_SETSTAT, process_setstat, 1 },
{ "fsetstat", NULL, SSH2_FXP_FSETSTAT, process_fsetstat, 1 },
{ "opendir", NULL, SSH2_FXP_OPENDIR, process_opendir, 0 },
{ "readdir", NULL, SSH2_FXP_READDIR, process_readdir, 0 },
{ "remove", NULL, SSH2_FXP_REMOVE, process_remove, 1 },
{ "mkdir", NULL, SSH2_FXP_MKDIR, process_mkdir, 1 },
{ "rmdir", NULL, SSH2_FXP_RMDIR, process_rmdir, 1 },
{ "realpath", NULL, SSH2_FXP_REALPATH, process_realpath, 0 },
{ "stat", NULL, SSH2_FXP_STAT, process_stat, 0 },
{ "rename", NULL, SSH2_FXP_RENAME, process_rename, 1 },
{ "readlink", NULL, SSH2_FXP_READLINK, process_readlink, 0 },
{ "symlink", NULL, SSH2_FXP_SYMLINK, process_symlink, 1 },
{ NULL, NULL, 0, NULL, 0 }
};
/* SSH2_FXP_EXTENDED submessages */
static const struct sftp_handler extended_handlers[] = {
{ "posix-rename", "[email protected]", 0,
process_extended_posix_rename, 1 },
{ "statvfs", "[email protected]", 0, process_extended_statvfs, 0 },
{ "fstatvfs", "[email protected]", 0, process_extended_fstatvfs, 0 },
{ "hardlink", "[email protected]", 0, process_extended_hardlink, 1 },
{ "fsync", "[email protected]", 0, process_extended_fsync, 1 },
{ "lsetstat", "[email protected]", 0, process_extended_lsetstat, 1 },
{ "limits", "[email protected]", 0, process_extended_limits, 0 },
{ "expand-path", "[email protected]", 0,
process_extended_expand, 0 },
{ "copy-data", "copy-data", 0, process_extended_copy_data, 1 },
{ "home-directory", "home-directory", 0,
process_extended_home_directory, 0 },
{ "users-groups-by-id", "[email protected]", 0,
process_extended_get_users_groups_by_id, 0 },
{ NULL, NULL, 0, NULL, 0 }
};
static const struct sftp_handler *
extended_handler_byname(const char *name)
{
int i;
for (i = 0; extended_handlers[i].handler != NULL; i++) {
if (strcmp(name, extended_handlers[i].ext_name) == 0)
return &extended_handlers[i];
}
return NULL;
}
static int
request_permitted(const struct sftp_handler *h)
{
char *result;
if (readonly && h->does_write) {
verbose("Refusing %s request in read-only mode", h->name);
return 0;
}
if (request_denylist != NULL &&
((result = match_list(h->name, request_denylist, NULL))) != NULL) {
free(result);
verbose("Refusing denylisted %s request", h->name);
return 0;
}
if (request_allowlist != NULL &&
((result = match_list(h->name, request_allowlist, NULL))) != NULL) {
free(result);
debug2("Permitting allowlisted %s request", h->name);
return 1;
}
if (request_allowlist != NULL) {
verbose("Refusing non-allowlisted %s request", h->name);
return 0;
}
return 1;
}
static int
errno_to_portable(int unixerrno)
{
int ret = 0;
switch (unixerrno) {
case 0:
ret = SSH2_FX_OK;
break;
case ENOENT:
case ENOTDIR:
case EBADF:
case ELOOP:
ret = SSH2_FX_NO_SUCH_FILE;
break;
case EPERM:
case EACCES:
case EFAULT:
ret = SSH2_FX_PERMISSION_DENIED;
break;
case ENAMETOOLONG:
case EINVAL:
ret = SSH2_FX_BAD_MESSAGE;
break;
case ENOSYS:
ret = SSH2_FX_OP_UNSUPPORTED;
break;
default:
ret = SSH2_FX_FAILURE;
break;
}
return ret;
}
static int
flags_from_portable(int pflags)
{
int flags = 0;
if ((pflags & SSH2_FXF_READ) &&
(pflags & SSH2_FXF_WRITE)) {
flags = O_RDWR;
} else if (pflags & SSH2_FXF_READ) {
flags = O_RDONLY;
} else if (pflags & SSH2_FXF_WRITE) {
flags = O_WRONLY;
}
if (pflags & SSH2_FXF_APPEND)
flags |= O_APPEND;
if (pflags & SSH2_FXF_CREAT)
flags |= O_CREAT;
if (pflags & SSH2_FXF_TRUNC)
flags |= O_TRUNC;
if (pflags & SSH2_FXF_EXCL)
flags |= O_EXCL;
return flags;
}
static const char *
string_from_portable(int pflags)
{
static char ret[128];
*ret = '\0';
#define PAPPEND(str) { \
if (*ret != '\0') \
strlcat(ret, ",", sizeof(ret)); \
strlcat(ret, str, sizeof(ret)); \
}
if (pflags & SSH2_FXF_READ)
PAPPEND("READ")
if (pflags & SSH2_FXF_WRITE)
PAPPEND("WRITE")
if (pflags & SSH2_FXF_APPEND)
PAPPEND("APPEND")
if (pflags & SSH2_FXF_CREAT)
PAPPEND("CREATE")
if (pflags & SSH2_FXF_TRUNC)
PAPPEND("TRUNCATE")
if (pflags & SSH2_FXF_EXCL)
PAPPEND("EXCL")
return ret;
}
/* handle handles */
typedef struct Handle Handle;
struct Handle {
int use;
DIR *dirp;
int fd;
int flags;
char *name;
u_int64_t bytes_read, bytes_write;
int next_unused;
};
enum {
HANDLE_UNUSED,
HANDLE_DIR,
HANDLE_FILE
};
static Handle *handles = NULL;
static u_int num_handles = 0;
static int first_unused_handle = -1;
static void handle_unused(int i)
{
handles[i].use = HANDLE_UNUSED;
handles[i].next_unused = first_unused_handle;
first_unused_handle = i;
}
static int
handle_new(int use, const char *name, int fd, int flags, DIR *dirp)
{
int i;
if (first_unused_handle == -1) {
if (num_handles + 1 <= num_handles)
return -1;
num_handles++;
handles = xreallocarray(handles, num_handles, sizeof(Handle));
handle_unused(num_handles - 1);
}
i = first_unused_handle;
first_unused_handle = handles[i].next_unused;
handles[i].use = use;
handles[i].dirp = dirp;
handles[i].fd = fd;
handles[i].flags = flags;
handles[i].name = xstrdup(name);
handles[i].bytes_read = handles[i].bytes_write = 0;
return i;
}
static int
handle_is_ok(int i, int type)
{
return i >= 0 && (u_int)i < num_handles && handles[i].use == type;
}
static int
handle_to_string(int handle, u_char **stringp, int *hlenp)
{
if (stringp == NULL || hlenp == NULL)
return -1;
*stringp = xmalloc(sizeof(int32_t));
put_u32(*stringp, handle);
*hlenp = sizeof(int32_t);
return 0;
}
static int
handle_from_string(const u_char *handle, u_int hlen)
{
int val;
if (hlen != sizeof(int32_t))
return -1;
val = get_u32(handle);
if (handle_is_ok(val, HANDLE_FILE) ||
handle_is_ok(val, HANDLE_DIR))
return val;
return -1;
}
static char *
handle_to_name(int handle)
{
if (handle_is_ok(handle, HANDLE_DIR)||
handle_is_ok(handle, HANDLE_FILE))
return handles[handle].name;
return NULL;
}
static DIR *
handle_to_dir(int handle)
{
if (handle_is_ok(handle, HANDLE_DIR))
return handles[handle].dirp;
return NULL;
}
static int
handle_to_fd(int handle)
{
if (handle_is_ok(handle, HANDLE_FILE))
return handles[handle].fd;
return -1;
}
static int
handle_to_flags(int handle)
{
if (handle_is_ok(handle, HANDLE_FILE))
return handles[handle].flags;
return 0;
}
static void
handle_update_read(int handle, ssize_t bytes)
{
if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0)
handles[handle].bytes_read += bytes;
}
static void
handle_update_write(int handle, ssize_t bytes)
{
if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0)
handles[handle].bytes_write += bytes;
}
static u_int64_t
handle_bytes_read(int handle)
{
if (handle_is_ok(handle, HANDLE_FILE))
return (handles[handle].bytes_read);
return 0;
}
static u_int64_t
handle_bytes_write(int handle)
{
if (handle_is_ok(handle, HANDLE_FILE))
return (handles[handle].bytes_write);
return 0;
}
static int
handle_close(int handle)
{
int ret = -1;
if (handle_is_ok(handle, HANDLE_FILE)) {
ret = close(handles[handle].fd);
free(handles[handle].name);
handle_unused(handle);
} else if (handle_is_ok(handle, HANDLE_DIR)) {
ret = closedir(handles[handle].dirp);
free(handles[handle].name);
handle_unused(handle);
} else {
errno = ENOENT;
}
return ret;
}
static void
handle_log_close(int handle, char *emsg)
{
if (handle_is_ok(handle, HANDLE_FILE)) {
logit("%s%sclose \"%s\" bytes read %llu written %llu",
emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ",
handle_to_name(handle),
(unsigned long long)handle_bytes_read(handle),
(unsigned long long)handle_bytes_write(handle));
} else {
logit("%s%sclosedir \"%s\"",
emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ",
handle_to_name(handle));
}
}
static void
handle_log_exit(void)
{
u_int i;
for (i = 0; i < num_handles; i++)
if (handles[i].use != HANDLE_UNUSED)
handle_log_close(i, "forced");
}
static int
get_handle(struct sshbuf *queue, int *hp)
{
u_char *handle;
int r;
size_t hlen;
*hp = -1;
if ((r = sshbuf_get_string(queue, &handle, &hlen)) != 0)
return r;
if (hlen < 256)
*hp = handle_from_string(handle, hlen);
free(handle);
return 0;
}
/* send replies */
static void
send_msg(struct sshbuf *m)
{
int r;
if ((r = sshbuf_put_stringb(oqueue, m)) != 0)
fatal_fr(r, "enqueue");
sshbuf_reset(m);
}
static const char *
status_to_message(u_int32_t status)
{
static const char * const status_messages[] = {
"Success", /* SSH_FX_OK */
"End of file", /* SSH_FX_EOF */
"No such file", /* SSH_FX_NO_SUCH_FILE */
"Permission denied", /* SSH_FX_PERMISSION_DENIED */
"Failure", /* SSH_FX_FAILURE */
"Bad message", /* SSH_FX_BAD_MESSAGE */
"No connection", /* SSH_FX_NO_CONNECTION */
"Connection lost", /* SSH_FX_CONNECTION_LOST */
"Operation unsupported", /* SSH_FX_OP_UNSUPPORTED */
"Unknown error" /* Others */
};
return (status_messages[MINIMUM(status,SSH2_FX_MAX)]);
}
static void
send_status_errmsg(u_int32_t id, u_int32_t status, const char *errmsg)
{
struct sshbuf *msg;
int r;
debug3("request %u: sent status %u", id, status);
if (log_level > SYSLOG_LEVEL_VERBOSE ||
(status != SSH2_FX_OK && status != SSH2_FX_EOF))
logit("sent status %s", status_to_message(status));
if ((msg = sshbuf_new()) == NULL)
fatal_f("sshbuf_new failed");
if ((r = sshbuf_put_u8(msg, SSH2_FXP_STATUS)) != 0 ||
(r = sshbuf_put_u32(msg, id)) != 0 ||
(r = sshbuf_put_u32(msg, status)) != 0)
fatal_fr(r, "compose");
if (version >= 3) {
if ((r = sshbuf_put_cstring(msg, errmsg == NULL ?
status_to_message(status) : errmsg)) != 0 ||
(r = sshbuf_put_cstring(msg, "")) != 0)
fatal_fr(r, "compose message");
}
send_msg(msg);
sshbuf_free(msg);
}
static void
send_status(u_int32_t id, u_int32_t status)
{
send_status_errmsg(id, status, NULL);
}
static void
send_data_or_handle(char type, u_int32_t id, const u_char *data, int dlen)
{
struct sshbuf *msg;
int r;
if ((msg = sshbuf_new()) == NULL)
fatal_f("sshbuf_new failed");
if ((r = sshbuf_put_u8(msg, type)) != 0 ||
(r = sshbuf_put_u32(msg, id)) != 0 ||
(r = sshbuf_put_string(msg, data, dlen)) != 0)
fatal_fr(r, "compose");
send_msg(msg);
sshbuf_free(msg);
}
static void
send_data(u_int32_t id, const u_char *data, int dlen)
{
debug("request %u: sent data len %d", id, dlen);
send_data_or_handle(SSH2_FXP_DATA, id, data, dlen);
}
static void
send_handle(u_int32_t id, int handle)
{
u_char *string;
int hlen;
handle_to_string(handle, &string, &hlen);
debug("request %u: sent handle %d", id, handle);
send_data_or_handle(SSH2_FXP_HANDLE, id, string, hlen);
free(string);
}
static void
send_names(u_int32_t id, int count, const Stat *stats)
{
struct sshbuf *msg;
int i, r;
if ((msg = sshbuf_new()) == NULL)
fatal_f("sshbuf_new failed");
if ((r = sshbuf_put_u8(msg, SSH2_FXP_NAME)) != 0 ||
(r = sshbuf_put_u32(msg, id)) != 0 ||
(r = sshbuf_put_u32(msg, count)) != 0)
fatal_fr(r, "compose");
debug("request %u: sent names count %d", id, count);
for (i = 0; i < count; i++) {
if ((r = sshbuf_put_cstring(msg, stats[i].name)) != 0 ||
(r = sshbuf_put_cstring(msg, stats[i].long_name)) != 0 ||
(r = encode_attrib(msg, &stats[i].attrib)) != 0)
fatal_fr(r, "compose filenames/attrib");
}
send_msg(msg);
sshbuf_free(msg);
}
static void
send_attrib(u_int32_t id, const Attrib *a)
{
struct sshbuf *msg;
int r;
debug("request %u: sent attrib have 0x%x", id, a->flags);
if ((msg = sshbuf_new()) == NULL)
fatal_f("sshbuf_new failed");
if ((r = sshbuf_put_u8(msg, SSH2_FXP_ATTRS)) != 0 ||
(r = sshbuf_put_u32(msg, id)) != 0 ||
(r = encode_attrib(msg, a)) != 0)
fatal_fr(r, "compose");
send_msg(msg);
sshbuf_free(msg);
}
static void
send_statvfs(u_int32_t id, struct statvfs *st)
{
struct sshbuf *msg;
u_int64_t flag;
int r;
flag = (st->f_flag & ST_RDONLY) ? SSH2_FXE_STATVFS_ST_RDONLY : 0;
flag |= (st->f_flag & ST_NOSUID) ? SSH2_FXE_STATVFS_ST_NOSUID : 0;
if ((msg = sshbuf_new()) == NULL)
fatal_f("sshbuf_new failed");
if ((r = sshbuf_put_u8(msg, SSH2_FXP_EXTENDED_REPLY)) != 0 ||
(r = sshbuf_put_u32(msg, id)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_bsize)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_frsize)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_blocks)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_bfree)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_bavail)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_files)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_ffree)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_favail)) != 0 ||
(r = sshbuf_put_u64(msg, FSID_TO_ULONG(st->f_fsid))) != 0 ||
(r = sshbuf_put_u64(msg, flag)) != 0 ||
(r = sshbuf_put_u64(msg, st->f_namemax)) != 0)
fatal_fr(r, "compose");
send_msg(msg);
sshbuf_free(msg);
}
/*
* Prepare SSH2_FXP_VERSION extension advertisement for a single extension.
* The extension is checked for permission prior to advertisement.
*/
static int
compose_extension(struct sshbuf *msg, const char *name, const char *ver)
{
int r;
const struct sftp_handler *exthnd;
if ((exthnd = extended_handler_byname(name)) == NULL)
fatal_f("internal error: no handler for %s", name);
if (!request_permitted(exthnd)) {
debug2_f("refusing to advertise disallowed extension %s", name);
return 0;
}
if ((r = sshbuf_put_cstring(msg, name)) != 0 ||
(r = sshbuf_put_cstring(msg, ver)) != 0)
fatal_fr(r, "compose %s", name);
return 0;
}
/* parse incoming */
static void
process_init(void)
{
struct sshbuf *msg;
int r;
if ((r = sshbuf_get_u32(iqueue, &version)) != 0)
fatal_fr(r, "parse");
verbose("received client version %u", version);
if ((msg = sshbuf_new()) == NULL)
fatal_f("sshbuf_new failed");
if ((r = sshbuf_put_u8(msg, SSH2_FXP_VERSION)) != 0 ||
(r = sshbuf_put_u32(msg, SSH2_FILEXFER_VERSION)) != 0)
fatal_fr(r, "compose");
/* extension advertisements */
compose_extension(msg, "[email protected]", "1");
compose_extension(msg, "[email protected]", "2");
compose_extension(msg, "[email protected]", "2");
compose_extension(msg, "[email protected]", "1");
compose_extension(msg, "[email protected]", "1");
compose_extension(msg, "[email protected]", "1");
compose_extension(msg, "[email protected]", "1");
compose_extension(msg, "[email protected]", "1");
compose_extension(msg, "copy-data", "1");
compose_extension(msg, "home-directory", "1");
compose_extension(msg, "[email protected]", "1");
send_msg(msg);
sshbuf_free(msg);
}
static void
process_open(u_int32_t id)
{
u_int32_t pflags;
Attrib a;
char *name;
int r, handle, fd, flags, mode, status = SSH2_FX_FAILURE;
if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0 ||
(r = sshbuf_get_u32(iqueue, &pflags)) != 0 || /* portable flags */
(r = decode_attrib(iqueue, &a)) != 0)
fatal_fr(r, "parse");
debug3("request %u: open flags %d", id, pflags);
flags = flags_from_portable(pflags);
mode = (a.flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? a.perm : 0666;
logit("open \"%s\" flags %s mode 0%o",
name, string_from_portable(pflags), mode);
if (readonly &&
((flags & O_ACCMODE) != O_RDONLY ||
(flags & (O_CREAT|O_TRUNC)) != 0)) {
verbose("Refusing open request in read-only mode");
status = SSH2_FX_PERMISSION_DENIED;
} else {
fd = open(name, flags, mode);
if (fd == -1) {
status = errno_to_portable(errno);
} else {
handle = handle_new(HANDLE_FILE, name, fd, flags, NULL);
if (handle < 0) {
close(fd);
} else {
send_handle(id, handle);
status = SSH2_FX_OK;
}
}
}
if (status != SSH2_FX_OK)
send_status(id, status);
free(name);
}
static void
process_close(u_int32_t id)
{
int r, handle, ret, status = SSH2_FX_FAILURE;
if ((r = get_handle(iqueue, &handle)) != 0)
fatal_fr(r, "parse");
debug3("request %u: close handle %u", id, handle);
handle_log_close(handle, NULL);
ret = handle_close(handle);
status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
send_status(id, status);
}
static void
process_read(u_int32_t id)
{
static u_char *buf;
static size_t buflen;
u_int32_t len;
int r, handle, fd, ret, status = SSH2_FX_FAILURE;
u_int64_t off;
if ((r = get_handle(iqueue, &handle)) != 0 ||
(r = sshbuf_get_u64(iqueue, &off)) != 0 ||
(r = sshbuf_get_u32(iqueue, &len)) != 0)
fatal_fr(r, "parse");
debug("request %u: read \"%s\" (handle %d) off %llu len %u",
id, handle_to_name(handle), handle, (unsigned long long)off, len);
if ((fd = handle_to_fd(handle)) == -1)
goto out;
if (len > SFTP_MAX_READ_LENGTH) {
debug2("read change len %u to %u", len, SFTP_MAX_READ_LENGTH);
len = SFTP_MAX_READ_LENGTH;
}
if (len > buflen) {
debug3_f("allocate %zu => %u", buflen, len);
if ((buf = realloc(buf, len)) == NULL)
fatal_f("realloc failed");
buflen = len;
}
if (lseek(fd, off, SEEK_SET) == -1) {
status = errno_to_portable(errno);
error_f("seek \"%.100s\": %s", handle_to_name(handle),
strerror(errno));
goto out;
}
if (len == 0) {
/* weird, but not strictly disallowed */
ret = 0;
} else if ((ret = read(fd, buf, len)) == -1) {
status = errno_to_portable(errno);
error_f("read \"%.100s\": %s", handle_to_name(handle),
strerror(errno));
goto out;
} else if (ret == 0) {
status = SSH2_FX_EOF;
goto out;
}
send_data(id, buf, ret);
handle_update_read(handle, ret);
/* success */
status = SSH2_FX_OK;
out:
if (status != SSH2_FX_OK)
send_status(id, status);
}
static void
process_write(u_int32_t id)
{
u_int64_t off;
size_t len;
int r, handle, fd, ret, status;
u_char *data;
if ((r = get_handle(iqueue, &handle)) != 0 ||
(r = sshbuf_get_u64(iqueue, &off)) != 0 ||
(r = sshbuf_get_string(iqueue, &data, &len)) != 0)
fatal_fr(r, "parse");
debug("request %u: write \"%s\" (handle %d) off %llu len %zu",
id, handle_to_name(handle), handle, (unsigned long long)off, len);
fd = handle_to_fd(handle);
if (fd < 0)
status = SSH2_FX_FAILURE;
else {
if (!(handle_to_flags(handle) & O_APPEND) &&
lseek(fd, off, SEEK_SET) == -1) {
status = errno_to_portable(errno);
error_f("seek \"%.100s\": %s", handle_to_name(handle),
strerror(errno));
} else {
/* XXX ATOMICIO ? */
ret = write(fd, data, len);
if (ret == -1) {
status = errno_to_portable(errno);
error_f("write \"%.100s\": %s",
handle_to_name(handle), strerror(errno));
} else if ((size_t)ret == len) {
status = SSH2_FX_OK;
handle_update_write(handle, ret);
} else {
debug2_f("nothing at all written");
status = SSH2_FX_FAILURE;
}
}
}
send_status(id, status);
free(data);
}
static void
process_do_stat(u_int32_t id, int do_lstat)
{
Attrib a;
struct stat st;
char *name;
int r, status = SSH2_FX_FAILURE;
if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0)
fatal_fr(r, "parse");
debug3("request %u: %sstat", id, do_lstat ? "l" : "");
verbose("%sstat name \"%s\"", do_lstat ? "l" : "", name);
r = do_lstat ? lstat(name, &st) : stat(name, &st);
if (r == -1) {
status = errno_to_portable(errno);
} else {
stat_to_attrib(&st, &a);
send_attrib(id, &a);
status = SSH2_FX_OK;
}
if (status != SSH2_FX_OK)
send_status(id, status);
free(name);
}
static void
process_stat(u_int32_t id)
{
process_do_stat(id, 0);
}
static void
process_lstat(u_int32_t id)
{
process_do_stat(id, 1);
}
static void
process_fstat(u_int32_t id)
{
Attrib a;
struct stat st;
int fd, r, handle, status = SSH2_FX_FAILURE;
if ((r = get_handle(iqueue, &handle)) != 0)
fatal_fr(r, "parse");
debug("request %u: fstat \"%s\" (handle %u)",
id, handle_to_name(handle), handle);
fd = handle_to_fd(handle);
if (fd >= 0) {
r = fstat(fd, &st);
if (r == -1) {
status = errno_to_portable(errno);
} else {
stat_to_attrib(&st, &a);
send_attrib(id, &a);
status = SSH2_FX_OK;
}
}
if (status != SSH2_FX_OK)
send_status(id, status);
}
static struct timeval *
attrib_to_tv(const Attrib *a)
{
static struct timeval tv[2];
tv[0].tv_sec = a->atime;
tv[0].tv_usec = 0;
tv[1].tv_sec = a->mtime;
tv[1].tv_usec = 0;
return tv;
}
static struct timespec *
attrib_to_ts(const Attrib *a)
{
static struct timespec ts[2];
ts[0].tv_sec = a->atime;
ts[0].tv_nsec = 0;
ts[1].tv_sec = a->mtime;
ts[1].tv_nsec = 0;
return ts;
}
static void
process_setstat(u_int32_t id)
{
Attrib a;
char *name;
int r, status = SSH2_FX_OK;
if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0 ||
(r = decode_attrib(iqueue, &a)) != 0)
fatal_fr(r, "parse");
debug("request %u: setstat name \"%s\"", id, name);
if (a.flags & SSH2_FILEXFER_ATTR_SIZE) {
logit("set \"%s\" size %llu",
name, (unsigned long long)a.size);