ExternalVendorCode/openwrt
1
0
Fork 0
mirror of https://github.com/openwrt/openwrt.git synced 2025-02-01 16:58:22 +00:00
Code Issues Actions 6 Packages Projects Releases Wiki Activity

dropbear: cherry-pick upstream patches

Browse Source 
critical fixes:
- libtommath: possible integer overflow (CVE-2023-36328)
- implement Strict KEX mode (CVE-2023-48795)

various fixes:
- fix DROPBEAR_DSS and DROPBEAR_RSA config options
- y2038 issues
- remove SO_LINGER socket option
- make banner reading failure non-fatal
- fix "noremotetcp" behavior
- don't try to shutdown a pty
- fix test for multiuser kernels

adds new features:
- option to bind to interface
- allow inetd with non-syslog
- ignore unsupported command line options with dropbearkey

Signed-off-by: Konstantin Demin <rockdrilla@gmail.com>
(cherry picked from commit b5cde260487eae86db1661a53e5e5e0823936aab)
[Only add the patches fixing security problems]
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Tested-by: Stijn Segers <foss@volatilesystems.org>
This commit is contained in:
Konstantin Demin 2024-01-09 03:40:01 +03:00 committed by Hauke Mehrtens
parent 6961fe98ec
commit 6549a711be
3 changed files with 338 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
package/network/services/dropbear/Makefile
View File

@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
PKG_NAME:=dropbear
PKG_VERSION:=2022.82
PKG_RELEASE:=5
PKG_RELEASE:=6
PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.bz2
PKG_SOURCE_URL:= \

121
package/network/services/dropbear/patches/015-libtommath-fix-possible-integer-overflow.patch Normal file
View File

@ -0,0 +1,121 @@
From 3b576d95dcf791d7b945e75f639da8f89c1685a2 Mon Sep 17 00:00:00 2001
From: czurnieden <czurnieden@gmx.de>
Date: Tue, 9 May 2023 17:17:12 +0200
Subject: Fix possible integer overflow
---
libtommath/bn_mp_2expt.c | 4 ++++
libtommath/bn_mp_grow.c | 4 ++++
libtommath/bn_mp_init_size.c | 5 +++++
libtommath/bn_mp_mul_2d.c | 4 ++++
libtommath/bn_s_mp_mul_digs.c | 4 ++++
libtommath/bn_s_mp_mul_digs_fast.c | 4 ++++
libtommath/bn_s_mp_mul_high_digs.c | 4 ++++
libtommath/bn_s_mp_mul_high_digs_fast.c | 4 ++++
8 files changed, 33 insertions(+)
--- a/libtommath/bn_mp_2expt.c
+++ b/libtommath/bn_mp_2expt.c
@@ -12,6 +12,10 @@ mp_err mp_2expt(mp_int *a, int b)
{
mp_err err;
+ if (b < 0) {
+ return MP_VAL;
+ }
+
/* zero a as per default */
mp_zero(a);
--- a/libtommath/bn_mp_grow.c
+++ b/libtommath/bn_mp_grow.c
@@ -9,6 +9,10 @@ mp_err mp_grow(mp_int *a, int size)
int i;
mp_digit *tmp;
+ if (size < 0) {
+ return MP_VAL;
+ }
+
/* if the alloc size is smaller alloc more ram */
if (a->alloc < size) {
/* reallocate the array a->dp
--- a/libtommath/bn_mp_init_size.c
+++ b/libtommath/bn_mp_init_size.c
@@ -6,6 +6,11 @@
/* init an mp_init for a given size */
mp_err mp_init_size(mp_int *a, int size)
{
+
+ if (size < 0) {
+ return MP_VAL;
+ }
+
size = MP_MAX(MP_MIN_PREC, size);
/* alloc mem */
--- a/libtommath/bn_mp_mul_2d.c
+++ b/libtommath/bn_mp_mul_2d.c
@@ -9,6 +9,10 @@ mp_err mp_mul_2d(const mp_int *a, int b,
mp_digit d;
mp_err err;
+ if (b < 0) {
+ return MP_VAL;
+ }
+
/* copy */
if (a != c) {
if ((err = mp_copy(a, c)) != MP_OKAY) {
--- a/libtommath/bn_s_mp_mul_digs.c
+++ b/libtommath/bn_s_mp_mul_digs.c
@@ -16,6 +16,10 @@ mp_err s_mp_mul_digs(const mp_int *a, co
mp_word r;
mp_digit tmpx, *tmpt, *tmpy;
+ if (digs < 0) {
+ return MP_VAL;
+ }
+
/* can we use the fast multiplier? */
if ((digs < MP_WARRAY) &&
(MP_MIN(a->used, b->used) < MP_MAXFAST)) {
--- a/libtommath/bn_s_mp_mul_digs_fast.c
+++ b/libtommath/bn_s_mp_mul_digs_fast.c
@@ -26,6 +26,10 @@ mp_err s_mp_mul_digs_fast(const mp_int *
mp_digit W[MP_WARRAY];
mp_word _W;
+ if (digs < 0) {
+ return MP_VAL;
+ }
+
/* grow the destination as required */
if (c->alloc < digs) {
if ((err = mp_grow(c, digs)) != MP_OKAY) {
--- a/libtommath/bn_s_mp_mul_high_digs.c
+++ b/libtommath/bn_s_mp_mul_high_digs.c
@@ -15,6 +15,10 @@ mp_err s_mp_mul_high_digs(const mp_int *
mp_word r;
mp_digit tmpx, *tmpt, *tmpy;
+ if (digs < 0) {
+ return MP_VAL;
+ }
+
/* can we use the fast multiplier? */
if (MP_HAS(S_MP_MUL_HIGH_DIGS_FAST)
&& ((a->used + b->used + 1) < MP_WARRAY)
--- a/libtommath/bn_s_mp_mul_high_digs_fast.c
+++ b/libtommath/bn_s_mp_mul_high_digs_fast.c
@@ -19,6 +19,10 @@ mp_err s_mp_mul_high_digs_fast(const mp_
mp_digit W[MP_WARRAY];
mp_word _W;
+ if (digs < 0) {
+ return MP_VAL;
+ }
+
/* grow the destination as required */
pa = a->used + b->used;
if (c->alloc < pa) {

216
package/network/services/dropbear/patches/021-Implement-Strict-KEX-mode.patch Normal file
View File

@ -0,0 +1,216 @@
From 6e43be5c7b99dbee49dc72b6f989f29fdd7e9356 Mon Sep 17 00:00:00 2001
From: Matt Johnston <matt@ucc.asn.au>
Date: Mon, 20 Nov 2023 14:02:47 +0800
Subject: Implement Strict KEX mode
As specified by OpenSSH with kex-strict-c-v00@openssh.com and
kex-strict-s-v00@openssh.com.
---
cli-session.c | 11 +++++++++++
common-algo.c | 6 ++++++
common-kex.c | 26 +++++++++++++++++++++++++-
kex.h | 3 +++
process-packet.c | 34 +++++++++++++++++++---------------
ssh.h | 4 ++++
svr-session.c | 3 +++
7 files changed, 71 insertions(+), 16 deletions(-)
--- a/cli-session.c
+++ b/cli-session.c
@@ -46,6 +46,7 @@ static void cli_finished(void) ATTRIB_NO
static void recv_msg_service_accept(void);
static void cli_session_cleanup(void);
static void recv_msg_global_request_cli(void);
+static void cli_algos_initialise(void);
struct clientsession cli_ses; /* GLOBAL */
@@ -117,6 +118,7 @@ void cli_session(int sock_in, int sock_o
}
chaninitialise(cli_chantypes);
+ cli_algos_initialise();
/* Set up cli_ses vars */
cli_session_init(proxy_cmd_pid);
@@ -487,3 +489,12 @@ void cli_dropbear_log(int priority, cons
fflush(stderr);
}
+static void cli_algos_initialise(void) {
+ algo_type *algo;
+ for (algo = sshkex; algo->name; algo++) {
+ if (strcmp(algo->name, SSH_STRICT_KEX_S) == 0) {
+ algo->usable = 0;
+ }
+ }
+}
+
--- a/common-algo.c
+++ b/common-algo.c
@@ -315,6 +315,12 @@ algo_type sshkex[] = {
{SSH_EXT_INFO_C, 0, NULL, 1, NULL},
#endif
#endif
+#if DROPBEAR_CLIENT
+ {SSH_STRICT_KEX_C, 0, NULL, 1, NULL},
+#endif
+#if DROPBEAR_SERVER
+ {SSH_STRICT_KEX_S, 0, NULL, 1, NULL},
+#endif
{NULL, 0, NULL, 0, NULL}
};
--- a/common-kex.c
+++ b/common-kex.c
@@ -183,6 +183,10 @@ void send_msg_newkeys() {
gen_new_keys();
switch_keys();
+ if (ses.kexstate.strict_kex) {
+ ses.transseq = 0;
+ }
+
TRACE(("leave send_msg_newkeys"))
}
@@ -193,7 +197,11 @@ void recv_msg_newkeys() {
ses.kexstate.recvnewkeys = 1;
switch_keys();
-
+
+ if (ses.kexstate.strict_kex) {
+ ses.recvseq = 0;
+ }
+
TRACE(("leave recv_msg_newkeys"))
}
@@ -550,6 +558,10 @@ void recv_msg_kexinit() {
ses.kexstate.recvkexinit = 1;
+ if (ses.kexstate.strict_kex && !ses.kexstate.donefirstkex && ses.recvseq != 1) {
+ dropbear_exit("First packet wasn't kexinit");
+ }
+
TRACE(("leave recv_msg_kexinit"))
}
@@ -859,6 +871,18 @@ static void read_kex_algos() {
}
#endif
+ if (!ses.kexstate.donefirstkex) {
+ const char* strict_name;
+ if (IS_DROPBEAR_CLIENT) {
+ strict_name = SSH_STRICT_KEX_S;
+ } else {
+ strict_name = SSH_STRICT_KEX_C;
+ }
+ if (buf_has_algo(ses.payload, strict_name) == DROPBEAR_SUCCESS) {
+ ses.kexstate.strict_kex = 1;
+ }
+ }
+
algo = buf_match_algo(ses.payload, sshkex, kexguess2, &goodguess);
allgood &= goodguess;
if (algo == NULL || algo->data == NULL) {
--- a/kex.h
+++ b/kex.h
@@ -83,6 +83,9 @@ struct KEXState {
unsigned our_first_follows_matches : 1;
+ /* Boolean indicating that strict kex mode is in use */
+ unsigned int strict_kex;
+
time_t lastkextime; /* time of the last kex */
unsigned int datatrans; /* data transmitted since last kex */
unsigned int datarecv; /* data received since last kex */
--- a/process-packet.c
+++ b/process-packet.c
@@ -44,6 +44,7 @@ void process_packet() {
unsigned char type;
unsigned int i;
+ unsigned int first_strict_kex = ses.kexstate.strict_kex && !ses.kexstate.donefirstkex;
time_t now;
TRACE2(("enter process_packet"))
@@ -54,22 +55,24 @@ void process_packet() {
now = monotonic_now();
ses.last_packet_time_keepalive_recv = now;
- /* These packets we can receive at any time */
- switch(type) {
- case SSH_MSG_IGNORE:
- goto out;
- case SSH_MSG_DEBUG:
- goto out;
-
- case SSH_MSG_UNIMPLEMENTED:
- /* debugging XXX */
- TRACE(("SSH_MSG_UNIMPLEMENTED"))
- goto out;
-
- case SSH_MSG_DISCONNECT:
- /* TODO cleanup? */
- dropbear_close("Disconnect received");
+ if (type == SSH_MSG_DISCONNECT) {
+ /* Allowed at any time */
+ dropbear_close("Disconnect received");
+ }
+
+ /* These packets may be received at any time,
+ except during first kex with strict kex */
+ if (!first_strict_kex) {
+ switch(type) {
+ case SSH_MSG_IGNORE:
+ goto out;
+ case SSH_MSG_DEBUG:
+ goto out;
+ case SSH_MSG_UNIMPLEMENTED:
+ TRACE(("SSH_MSG_UNIMPLEMENTED"))
+ goto out;
+ }
}
/* Ignore these packet types so that keepalives don't interfere with
@@ -98,7 +101,8 @@ void process_packet() {
if (type >= 1 && type <= 49
&& type != SSH_MSG_SERVICE_REQUEST
&& type != SSH_MSG_SERVICE_ACCEPT
- && type != SSH_MSG_KEXINIT)
+ && type != SSH_MSG_KEXINIT
+ && !first_strict_kex)
{
TRACE(("unknown allowed packet during kexinit"))
recv_unimplemented();
--- a/ssh.h
+++ b/ssh.h
@@ -100,6 +100,10 @@
#define SSH_EXT_INFO_C "ext-info-c"
#define SSH_SERVER_SIG_ALGS "server-sig-algs"
+/* OpenSSH strict KEX feature */
+#define SSH_STRICT_KEX_S "kex-strict-s-v00@openssh.com"
+#define SSH_STRICT_KEX_C "kex-strict-c-v00@openssh.com"
+
/* service types */
#define SSH_SERVICE_USERAUTH "ssh-userauth"
#define SSH_SERVICE_USERAUTH_LEN 12
--- a/svr-session.c
+++ b/svr-session.c
@@ -368,6 +368,9 @@ static void svr_algos_initialise(void) {
algo->usable = 0;
}
#endif
+ if (strcmp(algo->name, SSH_STRICT_KEX_C) == 0) {
+ algo->usable = 0;
+ }
}
}