.\" Copyright (c) 2019-2020 Rodolphe Bréard .\" .\" Copying and distribution of this file, with or without modification, .\" are permitted in any medium without royalty provided the copyright .\" notice and this notice are preserved. This file is offered as-is, .\" without any warranty. .Dd November 11, 2020 .Dt ACMED.TOML 5 .Os .Sh NAME .Nm acmed.toml .Nd ACMEd configuration file .Sh DESCRIPTION .Nm is the configuration file for .Xr acmed 8 . It is written in the .Em TOML format. The allowed elements are described below. .Bl -tag .It Ic account Array of table representing an account on one or several endpoint. .Bl -tag .It Ic contacts Ar array Array of tables describing describing the account holder's contact information. Each table must have one and only one key-value pair. Possible keys and their associated values are: .Bl -tag .It Ic mailto Ar string A mailto URI as defined by .Em RFC 6068 . This URI cannot contains neither .Dq hfields nor more than one .Dq addr-spec in the .Dq to component. .El .It Ic env Ar table Table of environment variables that will be accessible from hooks. .It Ic external_account Ar table Table containing the information required to bind the account to an external one. Possible fields and values are: .Bl -tag .It Ic identifier Ar string ASCII string identifying the key. .It Ic key Ar string Private key encoded in base64url without padding. .It Ic signature_algorithm Ar string Name of the signature algorithm used to sign the external account binding message sent to the endpoint as defined in .Em RFC 7518 . Possible values are: .Bl -dash -compact .It HS256 .Aq default .It HS384 .It HS512 .El .El .It Ic hooks Ar array Names of hooks that will be called during operations on the account storage file. The hooks are guaranteed to be called sequentially in the declaration order. .It Cm key_type Ar string Name of the asymmetric cryptography algorithm used to generate the key pair. Possible values are: .Bl -dash -compact .It ecdsa_p256 .Aq default .It ecdsa_p384 .It ecdsa_p521 .It rsa2048 .It rsa4096 .El .It Ic name Ar string The name the account is registered under. Must be unique. .It Cm signature_algorithm Ar string Name of the signature algorithm used to sign the messages sent to the endpoint as defined in .Em RFC 7518 . The default value is derived from the key type. Possible values are: .Bl -dash -compact .It ES256 .It ES384 .It ES512 .It RS256 .El .El .It Ic certificate Array of table representing a certificate that will be requested to a CA. .Pp Note that, by default, certificates are identified by the first identifier in the list of identifiers. That means that if you reorder the identifiers so that a different identifier is at the first position, a new certificate with a new name will be issued. .Bl -tag .It Ic account Ar string Name of the account to use. .It Ic csr_digest Ar string Name of the certificate's signing request digest algorithm. Possible values are: .Bl -dash -compact .It sha256 .Aq default .It sha384 .It sha512 .El .It Ic directory Ar string Path to the directory where certificates and their associated private keys are stored. .It Ic endpoint Ar string Name of the endpoint to use. .It Ic env Ar table Table of environment variables that will be accessible from hooks. .It Ic file_name_format Ar string Template used to build the file's name. The template syntax is .Em Handlebars . See the .Sx STANDARDS section for a link to the .Em Handlebars specifications. If not specified, the value defined in the .Em endpoint element, and then the .Em global element, is used. Default is .Dq {{name}}_{{key_type}}.{{file_type}}.{{ext}} . Possible variables are: .Bl -tag .It Ic ext Ar string File extension. Currently, only .Dq pem is supported. .It Ic file_type Ar string Contains .Dq pk for the private key file and .Dq crt for the certificate file. .It Ic key_type Ar string The certificate's private key type. .It Ic name Ar string The certificate's name. .El .It Ic hooks Ar array Names of hooks that will be called when requesting a new certificate. The hooks are guaranteed to be called sequentially in the declaration order. .It Ic identifiers Ar array Array of tables listing the identifiers that should be included in the certificate along with the challenge to use for each one. The .Em dns and .Em ip fields are mutually exclusive. .Bl -tag .It Ic challenge Ar string The name of the challenge to use to prove the identifier's ownership. Possible values are: .Bl -dash -compact .It dns-01 .It http-01 .It tls-alpn-01 .El .It Ic dns Ar string The domain name. .It Ic env Ar table Table of environment variables that will be accessible from hooks. .It Ic ip Ar string The IP address. .El .It Ic key_type Ar string Name of the asymmetric cryptography algorithm used to generate the certificate's key pair. Possible values are: .Bl -dash -compact .It ecdsa_p256 .It ecdsa_p384 .It ecdsa_p521 .It rsa2048 .Aq default .It rsa4096 .El .It Ic kp_reuse Ar boolean Set whether or not the private key should be reused when renewing the certificate. Default is false. .It Ic name Name of the certificate. Must be unique unless the key type is different. Will be used in logs and in the associated file's name. The .Sq * , .So : .Sc and .Sq / characters will be replaced by an underscore. Default is the first identifier. .It Cm renew_delay Ar string Period of time between the certificate renewal and its expiration date. The format is described in the .Sx TIME PERIODS section. Default is the value defined in the associated endpoint. .It Ic subject_attributes Ar table Table where the certificate's subject attributes are specified. Possible keys, with their RFC 4519 and X.500 equivalents, are: .Bl -column -offset indent ".Sy organizational_unit_name" ".Sy generationQualifier" ".Sy organizationalUnitName" .It Sy ACMEd key Ta Sy RFC 4519 Ta Sy X.500 .It Li country_name Ta c Ta countryName .It Li generation_qualifier Ta generationQualifier Ta .It Li given_name Ta givenName Ta .It Li initials Ta initials Ta .It Li locality_name Ta l Ta localityName .It Li name Ta name Ta .It Li organization_name Ta o Ta organizationName .It Li organizational_unit_name Ta ou Ta organizationalUnitName .It Li pkcs9_email_address Ta Ta .It Li postal_address Ta postalAddress Ta .It Li postal_code Ta postalCode Ta .It Li state_or_province_name Ta st Ta stateOrProvinceName .It Li street Ta street Ta streetAddress .It Li surname Ta sn Ta surname .It Li title Ta title Ta .El .El .It Ic endpoint Array of table where each element defines a Certificate Authority .Pq CA which may be used to request certificates. .Bl -tag .It Cm file_name_format Ar string Template used to build the file's name. For detailed documentation, see the .Em file_name_format directive located in the .Em certificate element. .It Cm name Ar string The name the endpoint is registered under. Must be unique. .It Cm rate_limits Ar array Array containing the names of the HTTPS rate limits to apply. .It Cm renew_delay Ar string Period of time between the certificate renewal and its expiration date. The format is described in the .Sx TIME PERIODS section. Default is the value defined in the global section. .It Cm root_certificates Ar array Array containing the path to root certificates that should be added to the trust store. .It Cm tos_agreed Ar boolean Set whether or not the user agrees to the Terms Of Service .Pq TOS . .It Cm url Ar string The endpoint's directory URL. .El .It Ic global Table containing the global configuration options. .Bl -tag .It Cm accounts_directory Ar string Specify the directory where the accounts private and public keys are stored. .It Cm cert_file_group Ar group_name|group_id Ft string Specify the group who will own newly-created certificates files. See .Xr chown 2 for more details. .It Cm cert_file_mode Ar integer Specify the permissions to use for newly-created certificates files. See .Xr chmod 2 for more details. .It Cm cert_file_user Ar username|user_id Ft string Specify the user who will own newly-created certificates files. See .Xr chown 2 for more details. .It Cm certificates_directory Ar string Specify the directory where the certificates and their associated private keys are stored. .It Ic env Ar table Table of environment variables that will be accessible from hooks. .It Ic file_name_format Ar string Template used to build the file's name. For detailed documentation, see the .Em file_name_format directive located in the .Em certificate element. .It Cm pk_file_group Ar group_name|group_id Ft string Specify the group who will own newly-created private-key files. See .Xr chown 2 for more details. .It Cm pk_file_mode Ar integer Specify the permissions to use for newly-created private-key files. See .Xr chmod 2 for more details. .It Cm pk_file_user Ar username|user_id Ft string Specify the user who will own newly-created private-key files. See .Xr chown 2 for more details. .It Cm renew_delay Ar string Period of time between the certificate renewal and its expiration date. The format is described in the .Sx TIME PERIODS section. Default is 3w. .It Cm root_certificates Ar array Array containing the path to root certificates that should be added to the trust store. .El .It Ic group Array of table allowing to group several hooks as one. A group is considered as new hook. .Bl -tag .It Cm hooks Ar array Array containing the names of the hooks that are grouped. The hooks are guaranteed to be called sequentially in the declaration order. .It Cm name Ar string The name the group is registered under. This name is considered as a hook name. Must be unique. .El .It Ic hook Array of table where each element defines a command that will be launched at a defined point. See section .Sx WRITING A HOOK for more details. .Bl -tag .It Cm allow_failure Ar boolean Defines if an error return value for this hook is allowed or not. If not allowed, a failure in this hook will fail the whole certificate request process. Default is false. .It Ic args Ar array Array of strings representing the command's arguments. .It Ic cmd Ar string The name of the command that will be launched. .It Cm name Ar string The name the hook is registered under. Must be unique. .It Ic stderr Ar string Path to the file where the command's standard error output if written. .It Ic stdin Ar string Path to the file that will be written into the command's standard intput. Mutually exclusive with .Em stdin_str . .It Ic stdin_str Ar string String that will be written into the command's standard input. Mutually exclusive with .Em stdin . .It Ic stdout Ar string Path to the file where the command's standard output if written. .It Cm type Ar array Array of strings. Possible types are: .Bl -dash -compact .It challenge-dns-01 .It challenge-dns-01-clean .It challenge-http-01 .It challenge-http-01-clean .It challenge-tls-alpn-01 .It challenge-tls-alpn-01-clean .It file-post-create .It file-post-edit .It file-pre-create .It file-pre-edit .It post-operation .El .El .It Ic include Array containing the path to configuration file to include. The path can be either relative or absolute. If relative, it is relative to the configuration file which included it. .Pp In case or overlapping global option definition, the one of the last included file will be used. For example, if a file .Em A includes files .Em B and .Em C and all three defines the same global option, the final value will be the one defined in file .Em C . .Pp Unix style globing is supported. .It Ic rate-limit Array of table where each element defines a HTTPS rate limit. .Bl -tag .It Cm name Ar string The name the rate limit is registered under. Must be unique. .It Cm number Ar integer Number of requests authorized withing the time period. .It Cm period Ar string Period of time during which a maximal number of requests is authorized. The format is described in the .Sx TIME PERIODS section. .El .El .Sh WRITING A HOOK When requesting a certificate from a CA using ACME, there are three steps that are hard to automatize. The first one is solving challenges in order to prove the ownership of every identifier to be included: it requires to interact with the configuration of other services, hence depends on how the infrastructure works. The second one is restarting all the services that use a given certificate, for the same reason. The last one is archiving: although several default methods can be implemented, sometimes admins wants or are required to do it in a different way. .Pp In order to allow full automation of the three above steps without imposing arbitrary restrictions or methods, .Xr acmed 8 uses hooks. Fundamentally, a hook is a command line template that will be called at a specific time of the process. Such an approach allows admins to use any executable script or program located on the machine to customize the process. .Pp For a given certificate, hooks are guaranteed to be called sequentially in the declaration order. It is therefore possible to have a hook that depends on another one. Nevertheless, several certificates may be renewed at the same time. Hence, hooks shall not use globing or any other action that may disrupt hooks called by a different certificate. .Pp A hook has a type that will influence both the moment it is called and the available template variables. It is possible to declare several types. In such a case, the hook will be invoked whenever one of its type request it. When called, the hook only have access to template variable for the current type. If a hook uses a template variable that does not exists for the current type it is invoked for, the variable is empty. .Pp When writing a hook, the values of .Em args , .Em stdin , .Em stdin_str , .Em stdout and .Em stderr are considered as template strings whereas .Em cmd is not. The template syntax is .Em Handlebars . See the .Sx STANDARDS section for a link to the .Em Handlebars specifications. .Pp The available types and the associated template variable are described below. .Bl -tag .It Ic challenge-dns-01 Invoked when the ownership of an identifier must be proved using the .Em dns-01 challenge. The available template variables are: .Bl -tag -compact .It Cm challenge Ar string The name of the challenge type .Aq dns-01 . Mostly used in hooks with multiple types. .It Cm env Ar array Array containing all the environment variables. .It Cm identifier Ar string The identifier name whom ownership is currently being validated. .It Cm is_clean_hook Ar bool False .It Cm proof Ar string The content of the proof that must be written to a .Ql TXT entry of the DNS zone for the .Ql _acme-challenge subdomain. .El .It Ic challenge-dns-01-clean Invoked once an identifier ownership has been proven using the .Em dns-01 challenge. This hook is intended to remove the proof since it is no longer required. The template variables are strictly identical to those given in the corresponding .Em challenge-dns-01 hook, excepted .Em is_clean_hook which is set to .Em true . .It Ic challenge-http-01 Invoked when the ownership of an identifier must be proved using the .Em http-01 challenge. The available template variables are: .Bl -tag -compact .It Cm challenge Ar string The name of the challenge type .Aq http-01 . Mostly used in hooks with multiple types. .It Cm env Ar array Array containing all the environment variables. .It Cm file_name Ar string Name of the file containing the proof. This is not a full path and does not include the .Ql .well-known/acme-challenge/ prefix. .It Cm identifier Ar string The identifier name whom ownership is currently being validated. .It Cm is_clean_hook Ar bool False .It Cm proof Ar string The content of the proof that must be written to .Em file_name . .El .It Ic challenge-http-01-clean Invoked once an identifier ownership has been proven using the .Em http-01 challenge. This hook is intended to remove the proof since it is no longer required. The template variables are strictly identical to those given in the corresponding .Em challenge-http-01 hook, excepted .Em is_clean_hook which is set to .Em true . .It Ic challenge-tls-alpn-01 Invoked when the ownership of an identifier must be proved using the .Em tls-alpn-01 challenge. The available template variables are: .Bl -tag -compact .It Cm challenge Ar string The name of the challenge type .Aq tls-alpn-01 . Mostly used in hooks with multiple types. .It Cm env Ar array Array containing all the environment variables. .It Cm identifier Ar string The identifier name whom ownership is currently being validated. .It Cm identifier_tls_alpn Ar string The identifier name whom ownership is currently being validated, in a form suitable for the TLS ALPN challenge. .It Cm is_clean_hook Ar bool False .It Cm proof Ar string Plain-text representation of the .Em acmeIdentifier extension that should be used in the self-signed certificate presented when a TLS connection is initiated with the .Qd acme-tls/1 ALPN extension value. .Xr acmed 8 will not generate the certificate itself since it can be done using .Xr tacd 8 . .El .It Ic challenge-tls-alpn-01-clean Invoked once an identifier ownership has been proven using the .Em tls-alpn-01 challenge. This hook is intended to remove the proof since it is no longer required. The template variables are strictly identical to those given in the corresponding .Em challenge-tls-alpn-01 hook, excepted .Em is_clean_hook which is set to .Em true . .It Ic file-post-create Invoked .Em after a non-existent file .Em created . The available template variables are the same as those available for the .Em file-pre-create type. .It Ic file-post-edit Invoked .Em after an existent file .Em modified . The available template variables are the same as those available for the .Em file-pre-create type. .It Ic file-pre-create Invoked .Em before a non-existent file .Em created . The available template variables are: .Bl -tag -compact .It Cm env Ar array Array containing all the environment variables. .It Cm file_directory Ar string Name of the directory where the impacted file is located. .It Cm file_name Ar string Name of the impacted file. .It Cm file_path Ar string Full path to the impacted file. .El .It Ic file-pre-edit Invoked .Em before an existent file .Em modified . The available template variables are the same as those available for the .Em file-pre-create type. .It Ic post-operation Invoked at the end of the certificate request process. The available template variables are: .Bl -tag -compact .It Cm env Ar array Array containing all the environment variables. .It Cm identifiers Ar string Array containing the identifiers included in the requested certificate. .It Cm is_success Ar boolean True if the certificate request is successful. .It Cm key_type Ar string Name of the asymmetric cryptography algorithm used to generate the certificate's key pair. .It Cm status Ar string Human-readable status. If the certificate request failed, it contains the error description. .El .El .Sh DEFAULT HOOKS Because many people have the same needs, ACMEd comes with a set of hooks that should serve most situations. Hook names being unique, the following names and any other name starting by those is reserved and should not be used. .Bl -tag .It Pa git This hook uses .Xr git 1 to archive private keys, public keys and certificates. It is possible to customize the commit username and email by using respectively the .Ev GIT_USERNAME and .Ev GIT_EMAIL environment variables. .It Pa http-01-echo This hook is designed to solve the http-01 challenge. For this purpose, it will write the proof into .Pa {{env.HTTP_ROOT}}/{{identifier}}/.well-known/acme-challenge/{{file_name}} . .Pp The web server must be configured so the file .Pa http://{{identifier}}/.well-known/acme-challenge/{{file_name}} can be accessed from the CA. .Pp If .Ev HTTP_ROOT is not specified, it will be set to .Pa /var/www . .It Pa tls-alpn-01-tacd-tcp This hook is designed to solve the tls-alpn-01 challenge using .Xr tacd 8 . It requires .Xr pkill 1 to support the .Em -F option. .Pp .Xr tacd 8 will listen on the host defined by the .Ev TACD_HOST environment variable (default is the identifier to be validated) and on the port defined by the .Ev TACD_PORT environment variable (default is 5001). .Pp .Xr tacd 8 will store its pid into .Pa {{TACD_PID_ROOT}}/tacd_{{identifier}}.pid . If .Ev TACD_PID_ROOT is not specified, it will be set to .Pa /run . .It Pa tls-alpn-01-tacd-unix This hook is designed to solve the tls-alpn-01 challenge using .Xr tacd 8 . It requires .Xr pkill 1 to support the .Em -F option. .Pp .Xr tacd 8 will listen on the unix socket .Pa {{env.TACD_SOCK_ROOT}}/tacd_{{identifier}}.sock . If .Ev TACD_SOCK_ROOT is not specified, it will be set to .Pa /run . .Pp .Xr tacd 8 will store its pid into .Pa {{TACD_PID_ROOT}}/tacd_{{identifier}}.pid . If .Ev TACD_PID_ROOT is not specified, it will be set to .Pa /run . .El .Sh TIME PERIODS ACMEd uses its own time period format, which is vaguely inspired by the ISO 8601 one. Periods are formatted as .Ar PM[PM...] where .Ar M is case sensitive character representing a length and .Ar P is an integer representing a multiplayer for the following length. The authorized length are: .Bl -dash -compact .It .Ar s : second .It .Ar m : minute .It .Ar h : hour .It .Ar d : day .It .Ar w : week .El The .Ar PM couples can be specified multiple times and in any order. .Pp For example, .Dq 1d42s and .Dq 40s20h4h2s both represents a period of one day and forty-two seconds. .Sh FILES .Bl -tag .It Pa /etc/acmed/accounts Default accounts private and public keys directory. .It Pa /etc/acmed/acmed.toml Default .Xr acmed 8 configuration file. .It Pa /etc/acmed/certs Default certificates and associated private keys directory. .El .Sh EXAMPLES The following example defines a typical endpoint, account and certificate for a domain, several subdomains and an IP address. .Bd -literal -offset indent [[endpoint]] name = "example name" url = "https://acme.example.org/directory" tos_agreed = true [[account]] name = "my test account" contacts = [ { mailto = "certs@exemple.net" } ] [[certificate]] endpoint = "example name" account = "my test account" identifiers = [ { dns = "exemple.net", challenge = "http-01"}, { dns = "1.exemple.net", challenge = "dns-01"}, { dns = "2.exemple.net", challenge = "tls-alpn-01", env.TACD_PORT="5010"}, { dns = "3.exemple.net", challenge = "tls-alpn-01", env.TACD_PORT="5011"}, { ip = "203.0.113.1", challenge = "http-01"}, ] hooks = ["git", "http-01-echo", "tls-alpn-01-tacd-tcp", "some-dns-01-hook"] env.HTTP_ROOT = "/srv/http" .Ed .Pp It is possible to use .Xr echo 1 to solve the .Em http-01 challenge and .Xr rm 1 to clean it. .Xr mkdir 1 and .Xr chmod 1 are used to prevent issues related to file access. .Bd -literal -offset indent [[hook]] name = "http-01-echo-mkdir" type = ["challenge-http-01"] cmd = "mkdir" args = [ "-m", "0755", "-p", "{{%if env.HTTP_ROOT}}{{env.HTTP_ROOT}}{{else}}/var/www{{/if}}/{{identifier}}/.well-known/acme-challenge" ] [[hook]] name = "http-01-echo-echo" type = ["challenge-http-01"] cmd = "echo" args = ["{{proof}}"] stdout = "{{%if env.HTTP_ROOT}}{{env.HTTP_ROOT}}{{else}}/var/www{{/if}}/{{identifier}}/.well-known/acme-challenge/{{file_name}}" [[hook]] name = "http-01-echo-chmod" type = ["challenge-http-01-clean"] cmd = "chmod" args = [ "a+r", "{{%if env.HTTP_ROOT}}{{env.HTTP_ROOT}}{{else}}/var/www{{/if}}/{{identifier}}/.well-known/acme-challenge/{{file_name}}" ] [[hook]] name = "http-01-echo-clean" type = ["challenge-http-01-clean"] cmd = "rm" args = [ "-f", "{{%if env.HTTP_ROOT}}{{env.HTTP_ROOT}}{{else}}/var/www{{/if}}/{{identifier}}/.well-known/acme-challenge/{{file_name}}" ] .Ed .Pp The hooks from the previous example can be grouped in order to reduce the number of hooks to define in the certificate. .Bd -literal -offset indent [[group]] name = "http-01-echo-var-www" hooks = [ "http-01-echo-mkdir", "http-01-echo-echo", "http-01-echo-chmod", "http-01-echo-clean" ] [[certificate]] # Some fields omitted hooks = ["http-01-echo"] env.HTTP_ROOT = "/srv/http" .Ed .Pp It is also possible to use .Xr sendmail 8 in a hook in order to notify someone when the certificate request process is done. .Bd -literal -offset indent [[hook]] name = "email-report" type = ["post-operation"] cmd = "sendmail" args = [ "-f", "noreply.certs@example.net", "contact@example.net" ] stdin_str = """Subject: Certificate renewal {{#if is_success}}succeeded{{else}}failed{{/if}} for {{identifiers.[0]}} The following certificate has {{#unless is_success}}*not* {{/unless}}been renewed. identifiers: {{#each identifiers}}{{#if @index}}, {{/if}}{{this}}{{/each}} key type: {{key_type}} status: {{status}}""" .Ed .Sh SEE ALSO .Xr acmed 8 , .Xr tacd 8 .Sh STANDARDS .Bl -hyphen .It .Rs .%A Tom Preston-Werner .%D July 2018 .%T TOML v0.5.0 .%U https://toml.io/en/v0.5.0 .Re .It .Rs .%A Yehuda Katz .%T Handlebars .%U https://handlebarsjs.com/ .Re .It .Rs .%A M. Jones .%D May 2015 .%R RFC 7518 .%T JSON Web Algorithms (JWA) .Re .El .Sh AUTHORS .An Rodolphe Bréard .Aq rodolphe@breard.tf