diff options
| author | Ed Maste <emaste@FreeBSD.org> | 2023-02-06 16:45:52 +0000 |
|---|---|---|
| committer | Ed Maste <emaste@FreeBSD.org> | 2023-02-08 21:04:36 +0000 |
| commit | 6ad91c17b0555f0d28377f66fb9f7c8b4cee2b06 (patch) | |
| tree | 439eb5d657e1031752e682d8a21624d95806a2de | |
| parent | 375bb3704d1371dec08f49cf8767f7b98162da34 (diff) | |
| download | src-6ad91c17b0555f0d28377f66fb9f7c8b4cee2b06.tar.gz src-6ad91c17b0555f0d28377f66fb9f7c8b4cee2b06.zip | |
ssh: Be more paranoid with host/domain names coming from the
never write a name with bad characters to a known_hosts file.
replace recently-added valid_domain() check for hostnames going to
known_hosts with a more relaxed check for bad characters.
Obtained from: OpenSSH-portable commit 445363433ba2
Obtained from: OpenSSH-portable commit 3cae9f92a318
Sponsored by: The FreeBSD Foundation
(cherry picked from commit 2e828220579e3ada74ed0613871ec6ec61d669ba)
| -rw-r--r-- | crypto/openssh/ssh.c | 8 | ||||
| -rw-r--r-- | crypto/openssh/sshconnect.c | 15 |
2 files changed, 19 insertions, 4 deletions
diff --git a/crypto/openssh/ssh.c b/crypto/openssh/ssh.c index 0c96f68bd8ae..549686b7798f 100644 --- a/crypto/openssh/ssh.c +++ b/crypto/openssh/ssh.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh.c,v 1.576 2022/09/17 10:33:18 djm Exp $ */ +/* $OpenBSD: ssh.c,v 1.579 2022/10/24 22:43:36 djm Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -251,6 +251,7 @@ static struct addrinfo * resolve_host(const char *name, int port, int logerr, char *cname, size_t clen) { char strport[NI_MAXSERV]; + const char *errstr = NULL; struct addrinfo hints, *res; int gaierr; LogLevel loglevel = SYSLOG_LEVEL_DEBUG1; @@ -276,7 +277,10 @@ resolve_host(const char *name, int port, int logerr, char *cname, size_t clen) return NULL; } if (cname != NULL && res->ai_canonname != NULL) { - if (strlcpy(cname, res->ai_canonname, clen) >= clen) { + if (!valid_domain(res->ai_canonname, 0, &errstr)) { + error("ignoring bad CNAME \"%s\" for host \"%s\": %s", + res->ai_canonname, name, errstr); + } else if (strlcpy(cname, res->ai_canonname, clen) >= clen) { error_f("host \"%s\" cname \"%s\" too long (max %lu)", name, res->ai_canonname, (u_long)clen); if (clen > 0) diff --git a/crypto/openssh/sshconnect.c b/crypto/openssh/sshconnect.c index eb5353e2d408..b44518d7acc7 100644 --- a/crypto/openssh/sshconnect.c +++ b/crypto/openssh/sshconnect.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sshconnect.c,v 1.358 2022/08/26 08:16:27 djm Exp $ */ +/* $OpenBSD: sshconnect.c,v 1.360 2022/11/03 21:59:20 djm Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -935,7 +935,7 @@ check_host_key(char *hostname, const struct ssh_conn_info *cinfo, char *ip = NULL, *host = NULL; char hostline[1000], *hostp, *fp, *ra; char msg[1024]; - const char *type, *fail_reason; + const char *type, *fail_reason = NULL; const struct hostkey_entry *host_found = NULL, *ip_found = NULL; int len, cancelled_forwarding = 0, confirmed; int local = sockaddr_is_local(hostaddr); @@ -961,6 +961,17 @@ check_host_key(char *hostname, const struct ssh_conn_info *cinfo, } /* + * Don't ever try to write an invalid name to a known hosts file. + * Note: do this before get_hostfile_hostname_ipaddr() to catch + * '[' or ']' in the name before they are added. + */ + if (strcspn(hostname, "@?*#[]|'\'\"\\") != strlen(hostname)) { + debug_f("invalid hostname \"%s\"; will not record: %s", + hostname, fail_reason); + readonly = RDONLY; + } + + /* * Prepare the hostname and address strings used for hostkey lookup. * In some cases, these will have a port number appended. */ |