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1 | <?xml version='1.0'?> <!--*-nxml-*--> |
2 | <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" | |
3 | "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> | |
4 | <!-- SPDX-License-Identifier: LGPL-2.1-or-later --> | |
5 | ||
6 | <refentry id="systemd-creds" | |
7 | xmlns:xi="http://www.w3.org/2001/XInclude"> | |
8 | ||
9 | <refentryinfo> | |
10 | <title>systemd-creds</title> | |
11 | <productname>systemd</productname> | |
12 | </refentryinfo> | |
13 | ||
14 | <refmeta> | |
15 | <refentrytitle>systemd-creds</refentrytitle> | |
16 | <manvolnum>1</manvolnum> | |
17 | </refmeta> | |
18 | ||
19 | <refnamediv> | |
20 | <refname>systemd-creds</refname> | |
21 | <refpurpose>Lists, shows, encrypts and decrypts service credentials</refpurpose> | |
22 | </refnamediv> | |
23 | ||
24 | <refsynopsisdiv> | |
25 | <cmdsynopsis> | |
26 | <command>systemd-creds</command> | |
27 | <arg choice="opt" rep="repeat">OPTIONS</arg> | |
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28 | <arg choice="plain">COMMAND</arg> |
29 | <arg choice="opt" rep="repeat">ARGS</arg> | |
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30 | </cmdsynopsis> |
31 | </refsynopsisdiv> | |
32 | ||
33 | <refsect1> | |
34 | <title>Description</title> | |
35 | ||
36 | <para><command>systemd-creds</command> is a tool for listing, showing, encrypting and decrypting unit | |
37 | credentials. Credentials are limited-size binary or textual objects that may be passed to unit | |
38 | processes. They are primarily used for passing cryptographic keys (both public and private) or | |
39 | certificates, user account information or identity information from the host to services.</para> | |
40 | ||
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41 | <para>Credentials are configured in unit files via the <varname>ImportCredential></varname>, |
42 | <varname>LoadCredential=</varname>, <varname>SetCredential=</varname>, | |
43 | <varname>LoadCredentialEncrypted=</varname> and <varname>SetCredentialEncrypted=</varname> settings, see | |
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44 | <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for |
45 | details.</para> | |
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46 | |
47 | <para>For further information see <ulink url="https://systemd.io/CREDENTIALS">System and Service | |
48 | Credentials</ulink> documentation.</para> | |
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49 | </refsect1> |
50 | ||
51 | <refsect1> | |
52 | <title>Commands</title> | |
53 | ||
54 | <para>The following commands are understood:</para> | |
55 | ||
56 | <variablelist> | |
57 | <varlistentry> | |
58 | <term><command>list</command></term> | |
59 | ||
60 | <listitem><para>Show a list of credentials passed into the current execution context. This command | |
61 | shows the files in the directory referenced by the <varname>$CREDENTIALS_DIRECTORY</varname> | |
62 | environment variable, and is intended to be executed from within service context.</para> | |
63 | ||
64 | <para>Along with each credential name, the size and security state is shown. The latter is one of | |
65 | <literal>secure</literal> (in case the credential is backed by unswappable memory, | |
66 | i.e. <literal>ramfs</literal>), <literal>weak</literal> (in case it is backed by any other type of | |
67 | memory), or <literal>insecure</literal> (if having any access mode that is not 0400, i.e. if readable | |
68 | by anyone but the owner).</para></listitem> | |
69 | </varlistentry> | |
70 | ||
71 | <varlistentry> | |
72 | <term><command>cat</command> <replaceable>credential...</replaceable></term> | |
73 | ||
74 | <listitem><para>Show contents of specified credentials passed into the current execution | |
75 | context. Takes one or more credential names, whose contents shall be written to standard | |
76 | output.</para> | |
77 | ||
78 | <para>When combined with <option>--json=</option> or <option>--transcode=</option> the output is | |
79 | transcoded in simple ways before outputting.</para></listitem> | |
80 | </varlistentry> | |
81 | ||
82 | <varlistentry> | |
83 | <term><command>setup</command></term> | |
84 | ||
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85 | <listitem><para>Generates a host encryption key for credentials, if one has not been generated |
86 | already. This ensures the <filename>/var/lib/systemd/credential.secret</filename> file is initialized | |
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87 | with a random secret key if it doesn't exist yet. This secret key is used when encrypting/decrypting |
88 | credentials with <command>encrypt</command> or <command>decrypt</command>, and is only accessible to | |
89 | the root user. Note that there's typically no need to invoke this command explicitly as it is | |
90 | implicitly called when <command>encrypt</command> is invoked, and credential host key encryption | |
91 | selected.</para></listitem> | |
92 | </varlistentry> | |
93 | ||
94 | <varlistentry> | |
ecc5d0c0 | 95 | <term><command>encrypt</command> <replaceable>input|-</replaceable> <replaceable>output|-</replaceable></term> |
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96 | |
97 | <listitem><para>Loads the specified (unencrypted plaintext) input credential file, encrypts it and | |
d43ea6c8 | 98 | writes the (encrypted ciphertext) output to the specified target credential file. The resulting file |
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99 | may be referenced in the <varname>LoadCredentialEncrypted=</varname> setting in unit files, or its |
100 | contents used literally in <varname>SetCredentialEncrypted=</varname> settings.</para> | |
101 | ||
102 | <para>Takes two file system paths. The file name part of the output path is embedded as name in the | |
103 | encrypted credential, to ensure encrypted credentials cannot be renamed and reused for different | |
104 | purposes without this being noticed. The credential name to embed may be overridden with the | |
105 | <option>--name=</option> setting. The input or output paths may be specified as <literal>-</literal>, | |
106 | in which case the credential data is read from/written to standard input and standard output. If the | |
107 | output path is specified as <literal>-</literal> the credential name cannot be derived from the file | |
108 | system path, and thus should be specified explicitly via the <option>--name=</option> switch.</para> | |
109 | ||
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110 | <para>The credential data is encrypted and authenticated symmetrically with one of the following |
111 | encryption keys:</para> | |
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112 | |
113 | <orderedlist> | |
114 | <listitem><para>A secret key automatically derived from the system's TPM2 chip. This encryption key | |
115 | is not stored on the host system and thus decryption is only possible with access to the original | |
116 | TPM2 chip. Or in other words, the credential secured in this way can only be decrypted again by the | |
117 | local machine.</para></listitem> | |
118 | ||
119 | <listitem><para>A secret key stored in the <filename>/var/lib/systemd/credential.secret</filename> | |
120 | file which is only accessible to the root user. This "host" encryption key is stored on the host | |
121 | file system, and thus decryption is possible with access to the host file system and sufficient | |
122 | privileges. The key is automatically generated when needed, but can also be created explicitly with | |
123 | the <command>setup</command> command, see above.</para></listitem> | |
124 | ||
125 | <listitem><para>A combination of the above: an encryption key derived from both the TPM2 chip and | |
126 | the host file system. This means decryption requires both access to the original TPM2 chip and the | |
127 | OS installation. This is the default mode of operation if a TPM2 chip is available and | |
128 | <filename>/var/lib/systemd/</filename> resides on persistent media.</para></listitem> | |
129 | </orderedlist> | |
130 | ||
131 | <para>Which of the three keys shall be used for encryption may be configured with the | |
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132 | <option>--with-key=</option> switch. Depending on the use-case for the encrypted credential the key |
133 | to use may differ. For example, for credentials that shall be accessible from the initrd, encryption | |
134 | with the host key is not appropriate, since access to the host key is typically not available from | |
135 | the initrd. Thus, for such credentials only the TPM2 key should be used.</para> | |
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136 | |
137 | <para>Encrypted credentials are always encoded in Base64.</para> | |
138 | ||
139 | <para>Use <command>decrypt</command> (see below) to undo the encryption operation, and acquire the | |
140 | decrypted plaintext credential from the encrypted ciphertext credential.</para> | |
141 | ||
142 | <para>The credential data is encrypted using AES256-GCM, i.e. providing both confidentiality and | |
143 | integrity, keyed by a SHA256 hash of one or both of the secret keys described above.</para> | |
144 | </listitem> | |
145 | </varlistentry> | |
146 | ||
147 | <varlistentry> | |
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148 | <term><command>decrypt</command> <replaceable>input|-</replaceable> |
149 | <optional><replaceable>output|-</replaceable></optional></term> | |
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150 | |
151 | <listitem><para>Undoes the effect of the <command>encrypt</command> operation: loads the specified | |
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152 | (encrypted ciphertext) input credential file, decrypts and authenticates it and writes the (decrypted |
153 | plaintext) output to the specified target credential file.</para> | |
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154 | |
155 | <para>Takes one or two file system paths. The file name part of the input path is compared with the | |
156 | credential name embedded in the encrypted file. If it does not match decryption fails. This is done | |
157 | in order to ensure that encrypted credentials are not re-purposed without this being detected. The | |
158 | credential name to compare with the embedded credential name may also be overridden with the | |
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159 | <option>--name=</option> switch. If the input path is specified as <literal>-</literal>, the |
160 | encrypted credential is read from standard input. If only one path is specified or the output path | |
161 | specified as <literal>-</literal>, the decrypted credential is written to standard output. In this | |
162 | mode, the expected name embedded in the credential cannot be derived from the path and should be | |
163 | specified explicitly with <option>--name=</option>.</para> | |
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164 | |
165 | <para>Decrypting credentials requires access to the original TPM2 chip and/or credentials host key, | |
166 | see above. Information about which keys are required is embedded in the encrypted credential data, | |
167 | and thus decryption is entirely automatic.</para></listitem> | |
168 | </varlistentry> | |
169 | ||
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170 | <varlistentry> |
171 | <term><command>has-tpm2</command></term> | |
172 | ||
173 | <listitem><para>Reports whether the system is equipped with a TPM2 device usable for protecting | |
6a1d8f11 | 174 | credentials. If a TPM2 device has been discovered, is supported, and is being used by firmware, |
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175 | by the OS kernel drivers and by userspace (i.e. systemd) this prints <literal>yes</literal> and exits |
176 | with exit status zero. If no such device is discovered/supported/used, prints | |
177 | <literal>no</literal>. Otherwise prints <literal>partial</literal>. In either of these two cases | |
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178 | exits with non-zero exit status. It also shows four lines indicating separately whether firmware, |
179 | drivers, the system and the kernel discovered/support/use TPM2.</para> | |
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180 | |
181 | <para>Combine with <option>--quiet</option> to suppress the output.</para></listitem> | |
182 | </varlistentry> | |
183 | ||
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184 | <xi:include href="standard-options.xml" xpointer="help" /> |
185 | <xi:include href="standard-options.xml" xpointer="version" /> | |
186 | </variablelist> | |
187 | </refsect1> | |
188 | ||
189 | <refsect1> | |
190 | <title>Options</title> | |
191 | ||
192 | <variablelist> | |
193 | ||
194 | <varlistentry> | |
195 | <term><option>--system</option></term> | |
196 | ||
197 | <listitem><para>When specified with the <command>list</command> and <command>cat</command> commands | |
198 | operates on the credentials passed to system as a whole instead of on those passed to the current | |
199 | execution context. This is useful in container environments where credentials may be passed in from | |
200 | the container manager.</para></listitem> | |
201 | </varlistentry> | |
202 | ||
203 | <varlistentry> | |
204 | <term><option>--transcode=</option></term> | |
205 | ||
206 | <listitem><para>When specified with the <command>cat</command> or <command>decrypt</command> | |
207 | commands, transcodes the output before showing it. Takes one of <literal>base64</literal>, | |
208 | <literal>unbase64</literal>, <literal>hex</literal> or <literal>unhex</literal> as argument, in order | |
209 | to encode/decode the credential data with Base64 or as series of hexadecimal values.</para> | |
210 | ||
211 | <para>Note that this has no effect on the <command>encrypt</command> command, as encrypted | |
212 | credentials are unconditionally encoded in Base64.</para></listitem> | |
213 | </varlistentry> | |
214 | ||
215 | <varlistentry> | |
216 | <term><option>--newline=</option></term> | |
217 | ||
218 | <listitem><para>When specified with <command>cat</command> or <command>decrypt</command> controls | |
219 | whether to add a trailing newline character to the end of the output if it doesn't end in one, | |
220 | anyway. Takes one of <literal>auto</literal>, <literal>yes</literal> or <literal>no</literal>. The | |
221 | default mode of <literal>auto</literal> will suffix the output with a single newline character only | |
222 | when writing credential data to a TTY.</para></listitem> | |
223 | </varlistentry> | |
224 | ||
225 | <varlistentry> | |
226 | <term><option>--pretty</option></term> | |
227 | <term><option>-p</option></term> | |
228 | ||
229 | <listitem><para>When specified with <command>encrypt</command> controls whether to show the encrypted | |
230 | credential as <varname>SetCredentialEncrypted=</varname> setting that may be pasted directly into a | |
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231 | unit file. Has effect only when used together with <option>--name=</option> and <literal>-</literal> |
232 | as the output file.</para></listitem> | |
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233 | </varlistentry> |
234 | ||
235 | <varlistentry> | |
236 | <term><option>--name=</option><replaceable>name</replaceable></term> | |
237 | ||
238 | <listitem><para>When specified with the <command>encrypt</command> command controls the credential | |
239 | name to embed in the encrypted credential data. If not specified the name is chosen automatically | |
240 | from the filename component of the specified output path. If specified as empty string no | |
241 | credential name is embedded in the encrypted credential, and no verification of credential name is | |
242 | done when the credential is decrypted.</para> | |
243 | ||
244 | <para>When specified with the <command>decrypt</command> command control the credential name to | |
245 | validate the credential name embedded in the encrypted credential with. If not specified the name is | |
246 | chosen automatically from the filename component of the specified input path. If no credential name | |
247 | is embedded in the encrypted credential file (i.e. the <option>--name=</option> with an empty string | |
248 | was used when encrypted) the specified name has no effect as no credential name validation is | |
249 | done.</para> | |
250 | ||
251 | <para>Embedding the credential name in the encrypted credential is done in order to protect against | |
252 | reuse of credentials for purposes they weren't originally intended for, under the assumption the | |
253 | credential name is chosen carefully to encode its intended purpose.</para></listitem> | |
254 | </varlistentry> | |
255 | ||
256 | <varlistentry> | |
257 | <term><option>--timestamp=</option><replaceable>timestamp</replaceable></term> | |
258 | ||
259 | <listitem><para>When specified with the <command>encrypt</command> command controls the timestamp to | |
260 | embed into the encrypted credential. Defaults to the current time. Takes a timestamp specification in | |
261 | the format described in | |
921e1bae | 262 | <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> |
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263 | |
264 | <para>When specified with the <command>decrypt</command> command controls the timestamp to use to | |
265 | validate the "not-after" timestamp that was configured with <option>--not-after=</option> during | |
266 | encryption. If not specified defaults to the current system time.</para></listitem> | |
267 | </varlistentry> | |
268 | ||
269 | <varlistentry> | |
270 | <term><option>--not-after=</option><replaceable>timestamp</replaceable></term> | |
271 | ||
272 | <listitem><para>When specified with the <command>encrypt</command> command controls the time when the | |
273 | credential shall not be used anymore. This embeds the specified timestamp in the encrypted | |
274 | credential. During decryption the timestamp is checked against the current system clock, and if the | |
275 | timestamp is in the past the decryption will fail. By default no such timestamp is set. Takes a | |
276 | timestamp specification in the format described in | |
921e1bae | 277 | <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para></listitem> |
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278 | </varlistentry> |
279 | ||
280 | <varlistentry> | |
281 | <term><option>--with-key=</option></term> | |
282 | <term><option>-H</option></term> | |
283 | <term><option>-T</option></term> | |
284 | ||
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285 | <listitem><para>When specified with the <command>encrypt</command> command controls the |
286 | encryption/signature key to use. Takes one of <literal>host</literal>, <literal>tpm2</literal>, | |
287 | <literal>host+tpm2</literal>, <literal>tpm2-absent</literal>, <literal>auto</literal>, | |
288 | <literal>auto-initrd</literal>. See above for details on the three key types. If set to | |
289 | <literal>auto</literal> (which is the default) the TPM2 key is used if a TPM2 device is found and not | |
290 | running in a container. The host key is used if <filename>/var/lib/systemd/</filename> is on | |
291 | persistent media. This means on typical systems the encryption is by default bound to both the TPM2 | |
292 | chip and the OS installation, and both need to be available to decrypt the credential again. If | |
293 | <literal>auto</literal> is selected but neither TPM2 is available (or running in container) nor | |
294 | <filename>/var/lib/systemd/</filename> is on persistent media, encryption will fail. If set to | |
295 | <literal>tpm2-absent</literal> a fixed zero length key is used (thus, in this mode no confidentiality | |
296 | nor authenticity are provided!). This logic is useful to cover for systems that lack a TPM2 chip but | |
297 | where credentials shall be generated. Note that decryption of such credentials is refused on systems | |
298 | that have a TPM2 chip and where UEFI SecureBoot is enabled (this is done so that such a locked down | |
299 | system cannot be tricked into loading a credential generated this way that lacks authentication | |
300 | information). If set to <literal>auto-initrd</literal> a TPM2 key is used if a TPM2 is found. If not | |
301 | a fixed zero length key is used, equivalent to <literal>tpm2-absent</literal> mode. This option is | |
302 | particularly useful to generate credentials files that are encrypted/authenticated against TPM2 where | |
303 | available but still work on systems lacking support for this.</para> | |
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304 | |
305 | <para>The <option>-H</option> switch is a shortcut for <option>--with-key=host</option>. Similar, | |
921e1bae | 306 | <option>-T</option> is a shortcut for <option>--with-key=tpm2</option>.</para> |
c1017f6b | 307 | |
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308 | <para>When encrypting credentials that shall be used in the initrd (where |
309 | <filename>/var/lib/systemd/</filename> is typically not available) make sure to use | |
b6553329 | 310 | <option>--with-key=auto-initrd</option> mode, to disable binding against the host secret.</para> |
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311 | |
312 | <para>This switch has no effect on the <command>decrypt</command> command, as information on which | |
313 | key to use for decryption is included in the encrypted credential already.</para></listitem> | |
314 | </varlistentry> | |
315 | ||
316 | <varlistentry> | |
317 | <term><option>--tpm2-device=</option><replaceable>PATH</replaceable></term> | |
318 | ||
319 | <listitem><para>Controls the TPM2 device to use. Expects a device node path referring to the TPM2 | |
320 | chip (e.g. <filename>/dev/tpmrm0</filename>). Alternatively the special value <literal>auto</literal> | |
321 | may be specified, in order to automatically determine the device node of a suitable TPM2 device (of | |
322 | which there must be exactly one). The special value <literal>list</literal> may be used to enumerate | |
323 | all suitable TPM2 devices currently discovered.</para></listitem> | |
324 | </varlistentry> | |
325 | ||
326 | <varlistentry> | |
327 | <term><option>--tpm2-pcrs=</option><arg rep="repeat">PCR</arg></term> | |
328 | ||
329 | <listitem><para>Configures the TPM2 PCRs (Platform Configuration Registers) to bind the encryption | |
330 | key to. Takes a <literal>+</literal> separated list of numeric PCR indexes in the range 0…23. If not | |
331 | used, defaults to PCR 7 only. If an empty string is specified, binds the encryption key to no PCRs at | |
332 | all. For details about the PCRs available, see the documentation of the switch of the same name for | |
333 | <citerefentry><refentrytitle>systemd-cryptenroll</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para></listitem> | |
334 | </varlistentry> | |
335 | ||
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336 | <varlistentry> |
337 | <term><option>--tpm2-public-key=</option><arg>PATH</arg></term> | |
338 | <term><option>--tpm2-public-key-pcrs=</option><arg rep="repeat">PCR</arg></term> | |
339 | ||
340 | <listitem><para>Configures a TPM2 signed PCR policy to bind encryption to, for use with the | |
341 | <command>encrypt</command> command. The <option>--tpm2-public-key=</option> option accepts a path to | |
342 | a PEM encoded RSA public key, to bind the encryption to. If this is not specified explicitly, but a | |
343 | file <filename>tpm2-pcr-public-key.pem</filename> exists in one of the directories | |
344 | <filename>/etc/systemd/</filename>, <filename>/run/systemd/</filename>, | |
345 | <filename>/usr/lib/systemd/</filename> (searched in this order), it is automatically used. The | |
346 | <option>--tpm2-public-key-pcrs=</option> option takes a list of TPM2 PCR indexes to bind to (same | |
347 | syntax as <option>--tpm2-pcrs=</option> described above). If not specified defaults to 11 (i.e. this | |
348 | binds the policy to any unified kernel image for which a PCR signature can be provided).</para> | |
349 | ||
350 | <para>Note the difference between <option>--tpm2-pcrs=</option> and | |
351 | <option>--tpm2-public-key-pcrs=</option>: the former binds decryption to the current, specific PCR | |
352 | values; the latter binds decryption to any set of PCR values for which a signature by the specified | |
353 | public key can be provided. The latter is hence more useful in scenarios where software updates shall | |
354 | be possible without losing access to all previously encrypted secrets.</para></listitem> | |
355 | </varlistentry> | |
356 | ||
357 | <varlistentry> | |
358 | <term><option>--tpm2-signature=</option><arg>PATH</arg></term> | |
359 | ||
360 | <listitem><para>Takes a path to a TPM2 PCR signature file as generated by the | |
361 | <citerefentry><refentrytitle>systemd-measure</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
362 | tool and that may be used to allow the <command>decrypt</command> command to decrypt credentials that | |
8b9f0921 | 363 | are bound to specific signed PCR values. If this is not specified explicitly, and a credential |
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364 | with a signed PCR policy is attempted to be decrypted, a suitable signature file |
365 | <filename>tpm2-pcr-signature.json</filename> is searched for in <filename>/etc/systemd/</filename>, | |
366 | <filename>/run/systemd/</filename>, <filename>/usr/lib/systemd/</filename> (in this order) and | |
367 | used.</para></listitem> | |
368 | </varlistentry> | |
369 | ||
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370 | <varlistentry> |
371 | <term><option>--quiet</option></term> | |
372 | <term><option>-q</option></term> | |
373 | ||
374 | <listitem><para>When used with <command>has-tpm2</command> suppresses the output, and only returns an | |
375 | exit status indicating support for TPM2.</para></listitem> | |
376 | </varlistentry> | |
377 | ||
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378 | <xi:include href="standard-options.xml" xpointer="no-pager" /> |
379 | <xi:include href="standard-options.xml" xpointer="no-legend" /> | |
380 | <xi:include href="standard-options.xml" xpointer="json" /> | |
381 | </variablelist> | |
382 | </refsect1> | |
383 | ||
384 | <refsect1> | |
385 | <title>Exit status</title> | |
386 | ||
387 | <para>On success, 0 is returned.</para> | |
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388 | |
389 | <para>In case of the <command>has-tpm2</command> command returns 0 if a TPM2 device is discovered, | |
390 | supported and used by firmware, driver, and userspace (i.e. systemd). Otherwise returns the OR | |
391 | combination of the value 1 (in case firmware support is missing), 2 (in case driver support is missing) | |
392 | and 4 (in case userspace support is missing). If no TPM2 support is available at all, value 7 is hence | |
393 | returned.</para> | |
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394 | </refsect1> |
395 | ||
396 | <refsect1> | |
397 | <title>Examples</title> | |
398 | ||
399 | <example> | |
400 | <title>Encrypt a password for use as credential</title> | |
401 | ||
402 | <para>The following command line encrypts the specified password <literal>hunter2</literal>, writing the result | |
403 | to a file <filename>password.cred</filename>.</para> | |
404 | ||
405 | <programlisting># echo -n hunter2 | systemd-creds encrypt - password.cred</programlisting> | |
406 | ||
407 | <para>This decrypts the file <filename>password.cred</filename> again, revealing the literal password:</para> | |
408 | ||
409 | <programlisting># systemd-creds decrypt password.cred | |
410 | hunter2</programlisting> | |
411 | </example> | |
412 | ||
413 | <example> | |
414 | <title>Encrypt a password and include it in a unit file</title> | |
415 | ||
416 | <para>The following command line prompts the user for a password and generates a | |
417 | <varname>SetCredentialEncrypted=</varname> line from it for a credential named | |
418 | <literal>mysql-password</literal>, suitable for inclusion in a unit file.</para> | |
419 | ||
420 | <programlisting># systemd-ask-password -n | systemd-creds encrypt --name=mysql-password -p - - | |
421 | 🔐 Password: **** | |
422 | SetCredentialEncrypted=mysql-password: \ | |
423 | k6iUCUh0RJCQyvL8k8q1UyAAAAABAAAADAAAABAAAAASfFsBoPLIm/dlDoGAAAAAAAAAA \ | |
424 | NAAAAAgAAAAAH4AILIOZ3w6rTzYsBy9G7liaCAd4i+Kpvs8mAgArzwuKxd0ABDjgSeO5k \ | |
425 | mKQc58zM94ZffyRmuNeX1lVHE+9e2YD87KfRFNoDLS7F3YmCb347gCiSk2an9egZ7Y0Xs \ | |
426 | 700Kr6heqQswQEemNEc62k9RJnEl2q7SbcEYguegnPQUATgAIAAsAAAASACA/B90W7E+6 \ | |
427 | yAR9NgiIJvxr9bpElztwzB5lUJAxtMBHIgAQACCaSV9DradOZz4EvO/LSaRyRSq2Hj0ym \ | |
428 | gVJk/dVzE8Uxj8H3RbsT7rIBH02CIgm/Gv1ukSXO3DMHmVQkDG0wEciyageTfrVEer8z5 \ | |
429 | 9cUQfM5ynSaV2UjeUWEHuz4fwDsXGLB9eELXLztzUU9nsAyLvs3ZRR+eEK/A==</programlisting> | |
430 | ||
431 | <para>The generated line can be pasted 1:1 into a unit file, and will ensure the acquired password will | |
432 | be made available in the <varname>$CREDENTIALS_DIRECTORY</varname><filename>/mysql-password</filename> | |
433 | credential file for the started service.</para> | |
434 | ||
435 | <para>Utilizing the unit file drop-in logic this can be used to securely pass a password credential to | |
436 | a unit. A similar, more comprehensive set of commands to insert a password into a service | |
437 | <filename>xyz.service</filename>:</para> | |
438 | ||
439 | <programlisting># mkdir -p /etc/systemd/system/xyz.service.d | |
7a17e41d | 440 | # systemd-ask-password -n | systemd-creds encrypt --name=mysql-password -p - - >/etc/systemd/system/xyz.service.d/50-password.conf |
c1017f6b LP |
441 | # systemctl daemon-reload |
442 | # systemctl restart xyz.service</programlisting> | |
443 | </example> | |
444 | </refsect1> | |
445 | ||
446 | <refsect1> | |
447 | <title>See Also</title> | |
448 | <para> | |
449 | <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
75ddec93 LP |
450 | <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
451 | <citerefentry><refentrytitle>systemd-measure</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
c1017f6b LP |
452 | </para> |
453 | </refsect1> | |
454 | ||
455 | </refentry> |