Open Build Service

We truncated the diff of some files because they were too big. If you want to see the full diff for every file, click here.

Changes of Revision 14

_service:tar_scm_kernel_repo:openssh.spec Changed

_service:tar_scm_kernel_repo:backport-CVE-2023-48795.patch Added

@@ -0,0 +1,465 @@
+From 802a7af111c9ddb438ca4fd8c5cc35534e199fda Mon Sep 17 00:00:00 2001
+From: "djm@openbsd.org" <djm@openbsd.org>
+Date: Mon, 18 Dec 2023 14:45:17 +0000
+Subject: upstream: implement "strict key exchange" in ssh and sshd
+
+This adds a protocol extension to improve the integrity of the SSH
+transport protocol, particular in and around the initial key exchange
+(KEX) phase.
+
+Full details of the extension are in the PROTOCOL file.
+
+with markus@
+
+OpenBSD-Commit-ID: 2a66ac962f0a630d7945fee54004ed9e9c439f14
+
+Origin: backport, https://anongit.mindrot.org/openssh.git/commit/?id=1edb00c58f8a6875fad6a497aa2bacf37f9e6cd5
+Last-Update: 2023-12-21
+
+Patch-Name: CVE-2023-48795.patch
+
+Reference:https://sources.debian.org/src/openssh/1%3A8.4p1-5%2Bdeb11u3/debian/patches/CVE-2023-48795.patch/
+Conflict:NA
+---
+ PROTOCOL      | 26 +++++++++++++++++
+ kex.c         | 68 ++++++++++++++++++++++++++++++++-----------
+ kex.h         |  1 +
+ packet.c      | 80 ++++++++++++++++++++++++++++++++++++++-------------
+ sshconnect2.c | 14 +++------
+ sshd.c        |  8 ++++--
+ 6 files changed, 149 insertions(+), 48 deletions(-)
+
+diff --git a/PROTOCOL b/PROTOCOL
+index f75c1c0..89bddfe 100644
+--- a/PROTOCOL
++++ b/PROTOCOL
+@@ -102,6 +102,32 @@ OpenSSH supports the use of ECDH in Curve25519 for key exchange as
+ described at:
+ http://git.libssh.org/users/aris/libssh.git/plain/doc/curve25519-sha256@libssh.org.txt?h=curve25519
+ 
++1.9 transport: strict key exchange extension
++
++OpenSSH supports a number of transport-layer hardening measures under
++a "strict KEX" feature. This feature is signalled similarly to the
++RFC8308 ext-info feature: by including a additional algorithm in the
++initiial SSH2_MSG_KEXINIT kex_algorithms field. The client may append
++"kex-strict-c-v00@openssh.com" to its kex_algorithms and the server
++may append "kex-strict-s-v00@openssh.com". These pseudo-algorithms
++are only valid in the initial SSH2_MSG_KEXINIT and MUST be ignored
++if they are present in subsequent SSH2_MSG_KEXINIT packets.
++
++When an endpoint that supports this extension observes this algorithm
++name in a peer's KEXINIT packet, it MUST make the following changes to
++the the protocol:
++
++a) During initial KEX, terminate the connection if any unexpected or
++   out-of-sequence packet is received. This includes terminating the
++   connection if the first packet received is not SSH2_MSG_KEXINIT.
++   Unexpected packets for the purpose of strict KEX include messages
++   that are otherwise valid at any time during the connection such as
++   SSH2_MSG_DEBUG and SSH2_MSG_IGNORE.
++b) After sending or receiving a SSH2_MSG_NEWKEYS message, reset the
++   packet sequence number to zero. This behaviour persists for the
++   duration of the connection (i.e. not just the first
++   SSH2_MSG_NEWKEYS).
++
+ 2. Connection protocol changes
+ 
+ 2.1. connection: Channel write close extension "eow@openssh.com"
+diff --git a/kex.c b/kex.c
+index 7c5f635..77eb7c0 100644
+--- a/kex.c
++++ b/kex.c
+@@ -72,7 +72,7 @@
+ #endif
+ 
+ /* prototype */
+-static int kex_choose_conf(struct ssh *);
++static int kex_choose_conf(struct ssh *, uint32_t seq);
+ static int kex_input_newkeys(int, u_int32_t, struct ssh *);
+ 
+ static const char *proposal_names[PROPOSAL_MAX] = {
+@@ -215,6 +215,18 @@ kex_names_valid(const char *names)
+ 	return 1;
+ }
+ 
++/* returns non-zero if proposal contains any algorithm from algs */
++static int
++has_any_alg(const char *proposal, const char *algs)
++{
++	char *cp;
++
++	if ((cp = match_list(proposal, algs, NULL)) == NULL)
++		return 0;
++	free(cp);
++	return 1;
++}
++
+ /*
+  * Concatenate algorithm names, avoiding duplicates in the process.
+  * Caller must free returned string.
+@@ -222,7 +234,7 @@ kex_names_valid(const char *names)
+ char *
+ kex_names_cat(const char *a, const char *b)
+ {
+-	char *ret = NULL, *tmp = NULL, *cp, *p, *m;
++	char *ret = NULL, *tmp = NULL, *cp, *p;
+ 	size_t len;
+ 
+ 	if (a == NULL || *a == '\0')
+@@ -239,10 +251,8 @@ kex_names_cat(const char *a, const char *b)
+ 	}
+ 	strlcpy(ret, a, len);
+ 	for ((p = strsep(&cp, ",")); p && *p != '\0'; (p = strsep(&cp, ","))) {
+-		if ((m = match_list(ret, p, NULL)) != NULL) {
+-			free(m);
++		if (has_any_alg(ret, p))
+ 			continue; /* Algorithm already present */
+-		}
+ 		if (strlcat(ret, ",", len) >= len ||
+ 		    strlcat(ret, p, len) >= len) {
+ 			free(tmp);
+@@ -474,7 +484,12 @@ kex_protocol_error(int type, u_int32_t seq, struct ssh *ssh)
+ {
+ 	int r;
+ 
+-	error("kex protocol error: type %d seq %u", type, seq);
++	/* If in strict mode, any unexpected message is an error */
++	if ((ssh->kex->flags & KEX_INITIAL) && ssh->kex->kex_strict) {
++		ssh_packet_disconnect(ssh, "strict KEX violation: "
++		    "unexpected packet type %u (seqnr %u)", type, seq);
++	}
++	error("%s: type %u seq %u", __func__, type, seq);
+ 	if ((r = sshpkt_start(ssh, SSH2_MSG_UNIMPLEMENTED)) != 0 ||
+ 	    (r = sshpkt_put_u32(ssh, seq)) != 0 ||
+ 	    (r = sshpkt_send(ssh)) != 0)
+@@ -546,6 +561,11 @@ kex_input_ext_info(int type, u_int32_t seq, struct ssh *ssh)
+ 	ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &kex_protocol_error);
+ 	if ((r = sshpkt_get_u32(ssh, &ninfo)) != 0)
+ 		return r;
++	if (ninfo >= 1024) {
++		error("SSH2_MSG_EXT_INFO with too many entries, expected "
++		    "<=1024, received %u", ninfo);
++		return dispatch_protocol_error(type, seq, ssh);
++	}
+ 	for (i = 0; i < ninfo; i++) {
+ 		if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0)
+ 			return r;
+@@ -646,7 +666,7 @@ kex_input_kexinit(int type, u_int32_t seq, struct ssh *ssh)
+ 		error("%s: no hex", __func__);
+ 		return SSH_ERR_INTERNAL_ERROR;
+ 	}
+-	ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, NULL);
++	ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, &kex_protocol_error);
+ 	ptr = sshpkt_ptr(ssh, &dlen);
+ 	if ((r = sshbuf_put(kex->peer, ptr, dlen)) != 0)
+ 		return r;
+@@ -682,7 +702,7 @@ kex_input_kexinit(int type, u_int32_t seq, struct ssh *ssh)
+ 	if (!(kex->flags & KEX_INIT_SENT))
+ 		if ((r = kex_send_kexinit(ssh)) != 0)
+ 			return r;
+-	if ((r = kex_choose_conf(ssh)) != 0)
++	if ((r = kex_choose_conf(ssh, seq)) != 0)
+ 		return r;
+ 
+ 	if (kex->kex_type < KEX_MAX && kex->kex[kex->kex_type] != NULL)
+@@ -960,7 +980,13 @@ proposals_match(char *my[PROPOSAL_MAX], char *peer[PROPOSAL_MAX])
+ }
+ 
+ static int
+-kex_choose_conf(struct ssh *ssh)
++kexalgs_contains(char **peer, const char *ext)
++{
++	return has_any_alg(peer[PROPOSAL_KEX_ALGS], ext);
++}
++
++static int
++kex_choose_conf(struct ssh *ssh, uint32_t seq)
+ {
+ 	struct kex *kex = ssh->kex;
+ 	struct newkeys *newkeys;
+@@ -985,13 +1011,23 @@ kex_choose_conf(struct ssh *ssh)
+ 		sprop=peer;
+ 	}
+ 
+-	/* Check whether client supports ext_info_c */
+-	if (kex->server && (kex->flags & KEX_INITIAL)) {
+-		char *ext;
+-
+-		ext = match_list("ext-info-c", peer[PROPOSAL_KEX_ALGS], NULL);
+-		kex->ext_info_c = (ext != NULL);
+-		free(ext);
++	/* Check whether peer supports ext_info/kex_strict */
++	if ((kex->flags & KEX_INITIAL) != 0) {
++		if (kex->server) {
++			kex->ext_info_c = kexalgs_contains(peer, "ext-info-c");
++			kex->kex_strict = kexalgs_contains(peer,
++			    "kex-strict-c-v00@openssh.com");
++		} else {
++			kex->kex_strict = kexalgs_contains(peer,