/
githubmirror
/
sudo
Обзор
Документация
Войти
/
githubmirror
/
sudo
Код
Запросы
0
Пакеты
0
Релизы
0
Аналитика
Безопасность
main
docs/sudo_logsrvd.mdoc.in
486 строк
15 KB
Todd C. Miller
Disable log_passwords by default in sudoers and sudo_logsrvd.conf.
26 окт 2025, 00:24
26 окт 2025, 00:24
6a1fe42
Код
Авторство
О чём код?
.\" .\" SPDX-License-Identifier: ISC .\" .\" Copyright (c) 2019-2025 Todd C. Miller <Todd.Miller@sudo.ws> .\" .\" Permission to use, copy, modify, and distribute this software for any .\" purpose with or without fee is hereby granted, provided that the above .\" copyright notice and this permission notice appear in all copies. .\" .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. .\" .Dd October 25, 2025 .Dt SUDO_LOGSRVD @mansectsu@ .Os Sudo @PACKAGE_VERSION@ .Sh NAME .Nm sudo_logsrvd .Nd sudo event and I/O log server .Sh SYNOPSIS .Nm sudo_logsrvd .Op Fl hnV .Op Fl f Ar file .Op Fl R Ar percentage .Sh DESCRIPTION .Nm is a high-performance log server that accepts event and I/O logs from .Nm sudo . It can be used to implement centralized logging of .Nm sudo logs. The server has two modes of operation: local and relay. By default, .Nm stores the logs locally but it can also be configured to relay them to another server that supports the .Xr sudo_logsrv.proto @mansectform@ protocol. .Pp When not relaying, event log entries may be logged either via .Xr syslog 3 or to a local file. I/O Logs stored locally by .Nm can be replayed via the .Xr sudoreplay @mansectsu@ utility in the same way as logs generated directly by the .Nm sudoers plugin. .Pp The server also supports restarting interrupted log transfers. To distinguish completed I/O logs from incomplete ones, the I/O log timing file is set to be read-only when the log is complete. .Pp Configuration parameters for .Nm may be specified in the .Xr sudo_logsrvd.conf @mansectform@ file or the file specified via the .Fl f option. .Pp The options are as follows: .Bl -tag -width Ds .It Fl f Ar file , Fl -file Ns = Ns Ar file Read configuration from .Ar file instead of the default, .Pa @sysconfdir@/sudo_logsrvd.conf . .It Fl h , -help Display a short help message to the standard output and exit. .It Fl n , -no-fork Run .Nm in the foreground instead of detaching from the terminal and becoming a daemon. .It Fl R Ar percentage , Fl -random-drop Ns = Ns Ar percentage For each message, there is a .Ar percentage chance that the server will drop the connection. This is only intended for debugging the ability of a client to restart a connection. .It Fl V , -version Print the .Nm version and exit. .El .Ss Securing server connections The I/O log data sent to .Nm may contain sensitive information such as passwords and should be secured using Transport Layer Security (TLS). Doing so requires having a signed certificate on the server and, if .Em tls_checkpeer is enabled in .Xr sudo_logsrvd.conf @mansectform@ , a signed certificate on the client as well. .Pp The certificates can either be signed by a well-known Certificate Authority (CA), or a private CA can be used. Instructions for creating a private CA are included below in the .Sx EXAMPLES section. .Ss Debugging sudo_logsrvd .Nm supports a flexible debugging framework that is configured via .Em Debug lines in the .Xr sudo.conf @mansectform@ file. .Pp For more information on configuring .Xr sudo.conf @mansectform@ , refer to its manual. .Sh SIGNALS .Nm responds to the following signals: .Bl -tag -width USR1 .It HUP Reload the configuration file. The event log file is closed and re-opened if logging to a file and not syslog. Active log connections are otherwise unaffected. .It USR1 Dump server state to the debug file (if one is configured). This includes a list of active client connections. .El .Sh FILES .Bl -tag -width 24n .It Pa @sysconfdir@/sudo.conf Sudo front-end configuration .It Pa @sysconfdir@/sudo_logsrvd.conf Sudo log server configuration file .It Pa @relay_dir@/incoming Directory where new journals are stored when the .Em store_first relay setting is enabled. .It Pa @relay_dir@/outgoing Directory where completed journals are stored when the .Em store_first relay setting is enabled. .It Pa @iolog_dir@ Default I/O log file location .It Pa @rundir@/sudo_logsrvd.pid Process ID file for .Nm .El .Sh EXAMPLES .Ss Creating self-signed certificates Unless you are using certificates signed by a well-known Certificate Authority (or a local enterprise CA), you will need to create your own CA that can sign the certificates used by .Nm , .Nm sudo_sendlog , and the .Nm sudoers plugin. The following steps use the .Xr openssl 1 command to create keys and certificates. .Ss Initial setup First, we need to create a directory structure to store the files for the CA. We'll create a new directory hierarchy in .Pa /etc/ssl/sudo for this purpose. .Bd -literal -offset 4n # mkdir /etc/ssl/sudo # cd /etc/ssl/sudo # mkdir certs csr newcerts private # chmod 700 private # touch index.txt index.txt.attr # echo 1000 > serial .Ed .Pp The serial and index.txt files are used to keep track of signed certificates. .Pp Next, we need to make a copy of the openssl.conf file and customize it for our new CA. The path to openssl.cnf is system-dependent but .Pa /etc/ssl/openssl.cnf is the most common location. You will need to adjust the example below if it has a different location on your system. .Bd -literal -offset 4n # cp /etc/ssl/openssl.cnf . .Ed .Pp Now edit the .Pa openssl.cnf file in the current directory and make sure it contains .Dq ca , .Dq CA_default , .Dq v3_ca , and .Dq usr_cert sections. Those sections should include at least the following settings: .Bd -literal -offset 4n [ ca ] default_ca = CA_default [ CA_default ] dir = /etc/ssl/sudo certs = $dir/certs database = $dir/index.txt private_key = $dir/private/cakey.pem certificate = $dir/cacert.pem new_certs_dir = $dir/newcerts serial = $dir/serial # Copy extension from the csr to the cert copy_extensions = copy # CA policy if you don't have one defined already. policy = policy_loose [ policy_loose ] # See POLICY FORMAT section in the "openssl-ca" manual. countryName = optional stateOrProvinceName = optional organizationName = optional organizationalUnitName = optional commonName = supplied emailAddress = optional [ v3_ca ] subjectKeyIdentifier = hash authorityKeyIdentifier = keyid:always,issuer basicConstraints = critical,CA:true keyUsage = cRLSign, keyCertSign [ usr_cert ] basicConstraints = CA:FALSE keyUsage = nonRepudiation, digitalSignature, \e keyEncipherment subjectKeyIdentifier = hash authorityKeyIdentifier = keyid,issuer .Ed .Pp If your .Pa openssl.conf file already has a .Dq CA_default section, you may only need to modify the .Dq dir setting and enable the .Dq keyUsage settings if they are commented out. .Ss Creating the CA key and certificate In order to create and sign our own certificates, we need to create a private key and a certificate for the root of the CA. First, create the private key and protect it with a pass phrase: .Bd -literal -offset 4n # openssl genrsa -aes256 -out private/cakey.pem 4096 # chmod 400 private/cakey.pem .Ed .Pp Next, generate the root certificate, using appropriate values for the site-specific fields: .Bd -literal -offset 4n # openssl req -config openssl.cnf -key private/cakey.pem \e -new -x509 -days 7300 -sha256 -extensions v3_ca \e -out cacert.pem Enter pass phrase for private/cakey.pem: You are about to be asked to enter information that will be incorporated into your certificate request. What you are about to enter is what is called a Distinguished Name or a DN. There are quite a few fields but you can leave some blank. For some fields there will be a default value, If you enter '.', the field will be left blank. ----- Country Name (2 letter code) [AU]:US State or Province Name (full name) [Some-State]:Colorado Locality Name (eg, city) []: Organization Name (eg, company) [Internet Widgets Pty Ltd]:sudo Organizational Unit Name (eg, section) []:sudo Certificate Authority Common Name (e.g., server FQDN or YOUR name) []:sudo Root CA Email Address []: # chmod 444 cacert.pem .Ed .Pp Finally, verify the root certificate: .Bd -literal -offset 4n # openssl x509 -noout -text -in cacert.pem .Ed .Ss Creating and signing certificates The server and client certificates will be signed by the previously created root CA. Usually, the root CA is not used to sign server/client certificates directly. Instead, intermediate certificates are created and signed with the root CA and the intermediate certs are used to sign CSRs (Certificate Signing Request). In this example we'll skip this part for simplicity's sake and sign the CSRs with the root CA. .Pp First, generate the private key without a pass phrase. .Bd -literal -offset 4n # openssl genrsa -out private/logsrvd_key.pem 2048 # chmod 400 private/logsrvd_key.pem .Ed .Pp Next, create a certificate signing request (CSR) for the server's certificate. The organization name must match the name given in the root certificate. The common name should be either the server's IP address or a fully qualified domain name. .Bd -literal -offset 4n # openssl req -config openssl.cnf -key private/logsrvd_key.pem -new \e -sha256 -out csr/logsrvd_csr.pem Enter pass phrase for private/logsrvd_key.pem: You are about to be asked to enter information that will be incorporated into your certificate request. What you are about to enter is what is called a Distinguished Name or a DN. There are quite a few fields but you can leave some blank. For some fields there will be a default value, If you enter '.', the field will be left blank. ----- Country Name (2 letter code) [AU]:US State or Province Name (full name) [Some-State]:Colorado Locality Name (eg, city) []: Organization Name (eg, company) [Internet Widgets Pty Ltd]:sudo Organizational Unit Name (eg, section) []:sudo log server Common Name (e.g., server FQDN or YOUR name) []:logserver.example.com Email Address []: Please enter the following 'extra' attributes to be sent with your certificate request A challenge password []: An optional company name []: .Ed .Pp To add additional DNS names (or IP addresses) to the request, set the Subject Alternative Name (SAN) by adding the something like the following to the above command. .Bd -literal -offset 4n -addext 'subjectAltName = DNS:other.example.com, IP:192.168.10.10' .Ed .Pp You may include zero or more DNS and IP entries, separated by a comma. This will only work if .Li copy_extensions has been enabled in the CA configuration. .Pp Now sign the CSR that was just created: .Bd -literal -offset 4n # openssl ca -config openssl.cnf -days 375 -notext -md sha256 \e -in csr/logsrvd_csr.pem -out certs/logsrvd_cert.pem Using configuration from openssl.cnf Enter pass phrase for ./private/cakey.pem: Check that the request matches the signature Signature ok Certificate Details: Serial Number: 4096 (0x1000) Validity Not Before: Nov 11 14:05:05 2019 GMT Not After : Nov 20 14:05:05 2020 GMT Subject: countryName = US stateOrProvinceName = Colorado organizationName = sudo organizationalUnitName = sudo log server commonName = logserve.example.com X509v3 extensions: X509v3 Basic Constraints: CA:FALSE X509v3 Key Usage: Digital Signature, Non Repudiation, Key Encipherment X509v3 Subject Key Identifier: 4C:50:F9:D0:BE:1A:4C:B2:AC:90:76:56:C7:9E:16:AE:E6:9E:E5:B5 X509v3 Authority Key Identifier: keyid:D7:91:24:16:B1:03:06:65:1A:7A:6E:CF:51:E9:5C:CB:7A:95:3E:0C Certificate is to be certified until Nov 20 14:05:05 2020 GMT (375 days) Sign the certificate? [y/n]:y 1 out of 1 certificate requests certified, commit? [y/n]y Write out database with 1 new entries Data Base Updated .Ed .Pp Finally, verify the new certificate: .Bd -literal -offset 4n # openssl verify -CAfile cacert.pem certs/logsrvd_cert.pem certs/logsrvd_cert.pem: OK .Ed .Pp The .Pa /etc/ssl/sudo/certs directory now contains a signed and verified certificate for use with .Nm sudo_logsrvd . .Pp To generate a client certificate, repeat the process above using a different file name. .Ss Configuring sudo_logsrvd to use TLS To use TLS for client/server communication, both .Nm and the .Nm sudoers plugin need to be configured to use TLS. Configuring .Nm for TLS requires the following settings, assuming the same path names used earlier: .Bd -literal -offset 4n # Listen on port 30344 for TLS connections to any address. listen_address = *:30344(tls) # Path to the certificate authority bundle file in PEM format. tls_cacert = /etc/ssl/sudo/cacert.pem # Path to the server's certificate file in PEM format. tls_cert = /etc/ssl/sudo/certs/logsrvd_cert.pem # Path to the server's private key file in PEM format. tls_key = /etc/ssl/sudo/private/logsrvd_key.pem .Ed .Pp The root CA cert .Pq Pa cacert.pem must be installed on the system running .Nm . If peer authentication is enabled on the client, a copy of .Pa cacert.pem must be present on the client system too. .Sh SEE ALSO .Xr sudo.conf @mansectform@ , .Xr sudo_logsrv.proto @mansectform@ , .Xr sudo_logsrvd.conf @mansectform@ , .Xr sudoers @mansectform@ , .Xr sudo @mansectsu@ , .Xr sudo_sendlog @mansectsu@ , .Xr sudoreplay @mansectsu@ .Sh AUTHORS Many people have worked on .Nm sudo over the years; this version consists of code written primarily by: .Bd -ragged -offset indent .An Todd C. Miller .Ed .Pp See the CONTRIBUTORS.md file in the .Nm sudo distribution (https://www.sudo.ws/about/contributors/) for an exhaustive list of people who have contributed to .Nm sudo . .Sh BUGS If you believe you have found a bug in .Nm , you can either file a bug report in the sudo bug database, https://bugzilla.sudo.ws/, or open an issue at https://github.com/sudo-project/sudo/issues. If you would prefer to use email, messages may be sent to the sudo-workers mailing list, https://www.sudo.ws/mailman/listinfo/sudo-workers (public) or <sudo@sudo.ws> (private). .Pp Please do not report security vulnerabilities through public GitHub issues, Bugzilla or mailing lists. Instead, report them via email to <Todd.Miller@sudo.ws>. You may encrypt your message with PGP if you would like, using the key found at https://www.sudo.ws/dist/PGPKEYS. .Sh SUPPORT Limited free support is available via the sudo-users mailing list, see https://www.sudo.ws/mailman/listinfo/sudo-users to subscribe or search the archives. .Sh DISCLAIMER .Nm is provided .Dq AS IS and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. See the LICENSE.md file distributed with .Nm sudo or https://www.sudo.ws/about/license/ for complete details.