diff options
Diffstat (limited to 'sftp-server.c')
| -rw-r--r-- | sftp-server.c | 43 |
1 files changed, 41 insertions, 2 deletions
diff --git a/sftp-server.c b/sftp-server.c index c80f0d3f..7300900a 100644 --- a/sftp-server.c +++ b/sftp-server.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sftp-server.c,v 1.121 2021/02/12 03:49:09 djm Exp $ */ +/* $OpenBSD: sftp-server.c,v 1.122 2021/02/18 00:30:17 djm Exp $ */ /* * Copyright (c) 2000-2004 Markus Friedl. All rights reserved. * @@ -19,6 +19,7 @@ #include <sys/types.h> #include <sys/stat.h> +#include <sys/resource.h> #ifdef HAVE_SYS_TIME_H # include <sys/time.h> #endif @@ -53,6 +54,9 @@ char *sftp_realpath(const char *, char *); /* sftp-realpath.c */ +/* Maximum data read that we are willing to accept */ +#define SFTP_MAX_READ_LENGTH (64 * 1024) + /* Our verbosity */ static LogLevel log_level = SYSLOG_LEVEL_ERROR; @@ -110,6 +114,7 @@ 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(u_int32_t id); struct sftp_handler { @@ -152,6 +157,7 @@ static const struct sftp_handler extended_handlers[] = { { "hardlink", "hardlink@openssh.com", 0, process_extended_hardlink, 1 }, { "fsync", "fsync@openssh.com", 0, process_extended_fsync, 1 }, { "lsetstat", "lsetstat@openssh.com", 0, process_extended_lsetstat, 1 }, + { "limits", "limits@openssh.com", 0, process_extended_limits, 1 }, { NULL, NULL, 0, NULL, 0 } }; @@ -673,6 +679,9 @@ process_init(void) (r = sshbuf_put_cstring(msg, "1")) != 0 || /* version */ /* lsetstat extension */ (r = sshbuf_put_cstring(msg, "lsetstat@openssh.com")) != 0 || + (r = sshbuf_put_cstring(msg, "1")) != 0 || /* version */ + /* limits extension */ + (r = sshbuf_put_cstring(msg, "limits@openssh.com")) != 0 || (r = sshbuf_put_cstring(msg, "1")) != 0) /* version */ fatal_fr(r, "compose"); send_msg(msg); @@ -739,7 +748,7 @@ process_close(u_int32_t id) static void process_read(u_int32_t id) { - u_char buf[64*1024]; + u_char buf[SFTP_MAX_READ_LENGTH]; u_int32_t len; int r, handle, fd, ret, status = SSH2_FX_FAILURE; u_int64_t off; @@ -1438,6 +1447,36 @@ process_extended_lsetstat(u_int32_t id) } static void +process_extended_limits(u_int32_t id) +{ + struct sshbuf *msg; + int r; + uint64_t nfiles = 0; + struct rlimit rlim; + + debug("request %u: limits", id); + + if (getrlimit(RLIMIT_NOFILE, &rlim) != -1 && rlim.rlim_cur > 5) + nfiles = rlim.rlim_cur - 5; /* stdio(3) + syslog + spare */ + + 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 || + /* max-packet-length */ + (r = sshbuf_put_u64(msg, SFTP_MAX_MSG_LENGTH)) != 0 || + /* max-read-length */ + (r = sshbuf_put_u64(msg, SFTP_MAX_READ_LENGTH)) != 0 || + /* max-write-length */ + (r = sshbuf_put_u64(msg, SFTP_MAX_MSG_LENGTH - 1024)) != 0 || + /* max-open-handles */ + (r = sshbuf_put_u64(msg, nfiles)) != 0) + fatal_fr(r, "compose"); + send_msg(msg); + sshbuf_free(msg); +} + +static void process_extended(u_int32_t id) { char *request; |