我最近将公司的 Mac Mini 设备从 Yosemite 升级到 El Capitan，在升级过程中遇到了几个问题。我已经解决了大部分问题，但仍然有一个问题无法解决，那就是 SSH 连接。该机器能够通过 SSH 连接到其他设备，但它接收传入 SSHD 连接的能力似乎部分受损。密码验证在机器上完全不起作用。我多次确认用户名和密码是正确的。我可以使用相同的凭据在本地登录，没有任何问题。我认为这与 sshd_config 中的 UsePAM 设置有关，因为当我关闭它时，公钥验证开始起作用，但打开它时却不起作用。
然而，在这两种情况下，密码验证都会 100% 失败。我尝试将 Mac 上的 OpenSSH 版本升级到 7.1p2，但这会完全破坏公钥验证，密码仍然会失败。Mac 版本仍然是 6.9，因为这是我唯一可以访问系统的版本。我包括了我能想到的所有日志输出，但我完全不知所措。
sshd_配置：
# $OpenBSD: sshd_config,v 1.89 2013/02/06 00:20:42 dtucker Exp $
# This is the sshd server system-wide configuration file. See
# sshd_config(5) for more information.
# This sshd was compiled with PATH=/usr/bin:/bin:/usr/sbin:/sbin
# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented. Uncommented options override the
# default value.
# See sshd_config(5) for details on setting the Port and Listen values on Mac OS X
#Port 22
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::
# The default requires explicit activation of protocol 1
#Protocol 2
# HostKey for protocol version 1
#HostKey /etc/ssh/ssh_host_key
# HostKeys for protocol version 2
#HostKey /etc/ssh/ssh_host_rsa_key
#HostKey /etc/ssh/ssh_host_dsa_key
#HostKey /etc/ssh/ssh_host_ecdsa_key
# Lifetime and size of ephemeral version 1 server key
#KeyRegenerationInterval 1h
#ServerKeyBits 1024
# Logging
# obsoletes QuietMode and FascistLogging
SyslogFacility AUTHPRIV
#LogLevel INFO
# Authentication:
#LoginGraceTime 2m
#PermitRootLogin yes
#noStrictModes yes
#MaxAuthTries 6
#MaxSessions 10
RSAAuthentication yes
PubkeyAuthentication yes
# The default is to check both .ssh/authorized_keys and .ssh/authorized_keys2
# but this is overridden so installations will only check .ssh/authorized_keys
AuthorizedKeysFile .ssh/authorized_keys
#AuthorizedPrincipalsFile none
#AuthorizedKeysCommand none
#AuthorizedKeysCommandUser nobody
# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
#RhostsRSAAuthentication no
# similar for protocol version 2
#HostbasedAuthentication no
# Change to yes if you don't trust ~/.ssh/known_hosts for
# RhostsRSAAuthentication and HostbasedAuthentication
#IgnoreUserKnownHosts no
# Don't read the user's ~/.rhosts and ~/.shosts files
#IgnoreRhosts yes
# To disable tunneled clear text passwords both PasswordAuthentication and
# ChallengeResponseAuthentication must be set to "no".
PasswordAuthentication yes
#PermitEmptyPasswords no
# Change to no to disable s/key passwords
ChallengeResponseAuthentication yes
# Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
#GSSAPIStrictAcceptorCheck yes
#GSSAPIKeyExchange no
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
# Also, PAM will deny null passwords by default. If you need to allow
# null passwords, add the " nullok" option to the end of the
# securityserver.so line in /etc/pam.d/sshd.
UsePAM no
#AllowAgentForwarding yes
#AllowTcpForwarding yes
#GatewayPorts no
X11Forwarding yes
#XauthLocation xauth # Default is to search $PATH (set by launchd(8)). It is recommended that a full path be provided.
#X11DisplayOffset 10
#X11UseLocalhost yes
#PrintMotd yes
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
UsePrivilegeSeparation sandbox # Default for new installations.
#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3
#UseDNS no
#PidFile /var/run/sshd.pid
#MaxStartups 10:30:100
#PermitTunnel no
#ChrootDirectory none
#VersionAddendum none
# pass locale information
AcceptEnv LANG LC_*
# no default banner path
#Banner none
# override default of no subsystems
Subsystem sftp /usr/libexec/sftp-server
# Example of overriding settings on a per-user basis
#Match User anoncvs
# X11Forwarding no
# AllowTcpForwarding no
# ForceCommand cvs server
# XAuthLocation added by XQuartz (http://xquartz.macosforge.org)
XAuthLocation /opt/X11/bin/xauth
LogLevel DEBUG3
密码验证（传入）：
OpenSSH_7.1p2, OpenSSL 1.0.2f 28 Jan 2016
debug1: Reading configuration data /usr/local/etc/ssh/ssh_config
debug2: ssh_connect: needpriv 0
debug1: Connecting to 192.168.1.113 [192.168.1.113] port 22.
debug1: Connection established.
debug1: identity file /Users/user_name/.ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/user_name/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/user_name/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/user_name/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/user_name/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/user_name/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/user_name/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/user_name/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.9
debug1: match: OpenSSH_6.9 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 192.168.1.113:22 as 'user'
debug3: hostkeys_foreach: reading file "/Users/user_name/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /Users/user_name/.ssh/known_hosts:2
debug3: load_hostkeys: loaded 1 keys from 192.168.1.113
debug3: order_hostkeyalgs: prefer hostkeyalgs: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected],[email protected],ssh-ed25519,ssh-rsa
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1,[email protected],[email protected],[email protected],[email protected],hmac-md5,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1,[email protected],[email protected],[email protected],[email protected],hmac-md5,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: first_kex_follows 0
debug2: reserved 0
debug2: kex_parse_kexinit: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ssh-ed25519
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: first_kex_follows 0
debug2: reserved 0
debug1: kex: server->client [email protected] <implicit> none
debug1: kex: client->server [email protected] <implicit> none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:R6FEOBAUOfi7AtDpRTFtCH3dRlZS06Z+idRfwFOJXjo
debug3: hostkeys_foreach: reading file "/Users/user_name/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /Users/user_name/.ssh/known_hosts:2
debug3: load_hostkeys: loaded 1 keys from 192.168.1.113
debug1: Host '192.168.1.113' is known and matches the ECDSA host key.
debug1: Found key in /Users/user_name/.ssh/known_hosts:2
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /Users/user_name/.ssh/id_rsa (0x7fc183d01c00),
debug2: key: /Users/user_name/.ssh/id_dsa (0x0),
debug2: key: /Users/user_name/.ssh/id_ecdsa (0x0),
debug2: key: /Users/user_name/.ssh/id_ed25519 (0x0),
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: start over, passed a different list publickey,password,keyboard-interactive
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /Users/user_name/.ssh/id_rsa
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug1: Trying private key: /Users/user_name/.ssh/id_dsa
debug3: no such identity: /Users/user_name/.ssh/id_dsa: No such file or directory
debug1: Trying private key: /Users/user_name/.ssh/id_ecdsa
debug3: no such identity: /Users/user_name/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /Users/user_name/.ssh/id_ed25519
debug3: no such identity: /Users/user_name/.ssh/id_ed25519: No such file or directory
debug2: we did not send a packet, disable method
debug3: authmethod_lookup keyboard-interactive
debug3: remaining preferred: password
debug3: authmethod_is_enabled keyboard-interactive
debug1: Next authentication method: keyboard-interactive
debug2: userauth_kbdint
debug2: we sent a keyboard-interactive packet, wait for reply
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: userauth_kbdint: disable: no info_req_seen
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred:
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
[email protected]'s password: debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug3: Received SSH2_MSG_IGNORE
debug2: we sent a password packet, wait for reply
debug1: Authentications that can continue: publickey,password,keyboard-interactive
Permission denied, please try again.
密码验证（system.log）：
Feb 10 11:45:34 Mac-mini launchproxy[95917]: Failed password for user from 192.168.1.111 port 57834 ssh2
Feb 10 11:45:35 Mac-mini launchproxy[95917]: Connection closed by 192.168.1.111 [preauth]
在 Mac 中进行公钥认证 - UsePAM = yes：
OpenSSH_7.1p1, OpenSSL 1.0.2e 3 Dec 2015
debug2: ssh_connect: needpriv 0
debug1: Connecting to 192.168.1.113 [192.168.1.113] port 22.
debug1: Connection established.
debug1: identity file /home/user/.ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/user/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/user/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/user/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/user/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/user/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/user/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/user/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.9
debug1: match: OpenSSH_6.9 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 192.168.1.113:22 as 'user_name'
debug3: hostkeys_foreach: reading file "/home/user/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/user/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from 192.168.1.113
debug3: order_hostkeyalgs: prefer hostkeyalgs: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected],[email protected],ssh-ed25519,ssh-rsa
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1,[email protected],[email protected],[email protected],[email protected],hmac-md5,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1,[email protected],[email protected],[email protected],[email protected],hmac-md5,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ssh-ed25519
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug1: kex: server->client [email protected] <implicit> none
debug1: kex: client->server [email protected] <implicit> none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:R6FEOBAUOfi7AtDpRTFtCH3dRlZS06Z+idRfwFOJXjo
debug3: hostkeys_foreach: reading file "/home/user/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/user/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from 192.168.1.113
debug1: Host '192.168.1.113' is known and matches the ECDSA host key.
debug1: Found key in /home/user/.ssh/known_hosts:1
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/user/.ssh/id_rsa (0x8005f138),
debug2: key: /home/user/.ssh/id_dsa (0x0),
debug2: key: /home/user/.ssh/id_ecdsa (0x0),
debug2: key: /home/user/.ssh/id_ed25519 (0x0),
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: start over, passed a different list publickey,password,keyboard-interactive
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/user/.ssh/id_rsa
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
debug1: Server accepts key: pkalg ssh-rsa blen 279
debug2: input_userauth_pk_ok: fp SHA256:SRMkKVOLgsg8NQHSJ89WqcJeW9sB5pj7ho7/pwmbjYI
debug3: sign_and_send_pubkey: RSA SHA256:SRMkKVOLgsg8NQHSJ89WqcJeW9sB5pj7ho7/pwmbjYI
Connection closed by 192.168.1.113