Internet Draft F. Gennai
Intended status: Informational A. Shahin
Expires: February 05, 2011 ISTI-CNR
C. Petrucci
DigitPA
A. Vinciarelli
July 26, 2010
Certified Electronic Mail
draft-gennai-smime-cnipa-pec-07.txt
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Copyright Notice
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Abstract
Since 1997, the Italian Laws have recognized electronic delivery
systems as legally usable. In 2005 after two years of technical
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tests, the characteristics of an official electronic delivery
service, named certified electronic mail (in Italian "Posta
Elettronica Certificata") were defined, giving the system legal
standing.
Design of the entire system was carried out by the National Center
for Informatics in the Public Administration of Italy (DigitPA),
followed by efforts for the implementation and testing of the
service. The DigitPA has given the Italian National Research Council
(CNR), and in particular The Institute of Information Science and
Technologies at the CNR (ISTI), the task of running tests on
providers of the service to guarantee the correct implementation and
interoperability. This document describes the certified email system
adopted in Italy. It represents the system as it is at the moment of
writing, following the technical regulations that were written based
upon the Italian Law DPR. November 2, 2005.
Table of Contents
1. Introduction .................................................. 4
1.1. Scope .................................................... 4
1.2. Notational Conventions ................................... 4
1.2.1. Requirement Conventions ........................... 4
1.2.2. Acronyms .......................................... 5
1.2.3. Terminology and Definitions ....................... 5
2. PEC model ..................................................... 6
2.1. System-generated messages ................................ 6
2.1.1. Message types ..................................... 8
2.2. Basic structure ......................................... 10
2.2.1. Access point ..................................... 10
2.2.2. Incoming point ................................... 12
2.2.3. Delivery point ................................... 14
2.2.4. Storage .......................................... 15
2.2.5. Provider service mailbox ......................... 15
2.2.6. Provider service email address ................... 15
2.3. Log ..................................................... 15
3. Message processing ........................................... 16
3.1. Access point ............................................ 16
3.1.1. Formal checks on messages ........................ 16
3.1.2. Non-acceptance PEC notification due to formal
exceptions ....................................... 17
3.1.3. Non-acceptance PEC notification due to virus
detection ........................................ 18
3.1.4. Acceptance PEC notification ...................... 18
3.1.5. PEC Transport envelope ........................... 19
3.1.6. Timeout delivery error PEC notification .......... 21
3.2. Incoming point .......................................... 22
3.2.1. Take in charge PEC notification .................. 22
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3.2.2. Anomaly envelope ................................. 23
3.2.3. Virus detection PEC notification ................. 24
3.2.4. Virus-induced delivery error PEC notification .... 25
3.3. Delivery point .......................................... 26
3.3.1. Checks on incoming messages ...................... 26
3.3.2. Delivery PEC notification ........................ 26
3.3.3. Non-delivery PEC notification .................... 31
3.4. Sender and receiver belonging to the same domain ........ 31
3.5. Example: Complete transaction between 2 PEC domains ..... 31
4. Formats ...................................................... 32
4.1. Temporal reference ...................................... 32
4.2. User date/time .......................................... 33
4.3. Format of a PEC message body ............................ 33
4.3.1. User readable text ............................... 34
4.3.2. Original message ................................. 34
4.3.3. Certification data ............................... 34
4.4. Certification data scheme ............................... 34
4.5. PEC providers directory scheme .......................... 36
4.5.1. providerCertificateHash attribute ................ 37
4.5.2. providerCertificate attribute .................... 38
4.5.3. providerName attribute ........................... 38
4.5.4. mailReceipt attribute ............................ 38
4.5.5. managedDomains attribute ......................... 39
4.5.6. LDIFLocationURL attribute ........................ 39
4.5.7. providerUnit attribute ........................... 39
4.5.8. LDIFLocationURLObject object class ............... 40
4.5.9. provider object class ............................ 40
4.5.10. LDIF file example ............................... 41
5. Security-related aspects ..................................... 44
5.1. Digital signature ....................................... 44
5.2. Authentication .......................................... 45
5.3. Secure interaction ...................................... 45
5.4. Virus ................................................... 45
5.5. S/MIME certificate ...................................... 46
5.5.1. Provider-related information (subject) ........... 46
5.5.2. Certificate extensions ........................... 46
5.5.3. Example .......................................... 47
5.6. PEC providers directory ................................. 51
6. PEC system client technical and functional prerequisites ..... 51
7. Security Considerations ...................................... 51
8. IANA Considerations .......................................... 52
8.1. Registration of PEC message header fields ............... 52
8.2. Registration of LDAP object identifier descriptors ...... 54
9. References ................................................... 56
9.1. Normative References .................................... 56
10. Acknowledgments ............................................. 58
Appendix A: Italian fields and values in English ................ 59
Appendix B: Change History ...................................... 61
Authors' Addresses .............................................. 63
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1. Introduction
Since 1997, the Italian Laws have recognized electronic delivery
systems as legally usable. In 2005 after two years of technical
tests, the characteristics of an official electronic delivery
service, named certified electronic mail (in Italian Posta
Elettronica Certificata, from now on "PEC") were defined, giving
the system legal standing.
This document represents the English version of the Italian
specfications, (http://www.cnipa.gov.it/site/_files/Pec-def.pdf)
which will be the ultimate PEC reference.
1.1. Scope
To ensure secure transactions over the Internet, cryptography can
be associated with electronic messages in order to provide some
guarantee on sender identity, message integrity, confidentiality,
and non-repudiation of origin. Many end-to-end techniques exist to
accomplish such goals, and some offer a high level of security. The
downside of end-to-end cryptography is the need for an extensive
penetration of technology in society, because it is essential for
every user to have asymmetric keys and certificates signed by a
Certification Authority. Along with that, users would need to have
an adequate amount of knowledge regarding the use of such
technology.
PEC on the other hand uses applications running on servers to
digitally sign messages, thus avoiding the complexity end-to-end
systems bring about. By doing so, the user needs only have an
ordinary mail client with which to interact. The downside is that
the level of security drops, since the protection does not cover the
entire transaction. Nonetheless, application is simpler and does not
require specific user skills, making it easily more widespread among
users.
This document describes PEC's technical aspects and features. It
presents the details of the protocol and the messages that are sent
between service providers, introducing the system adopted by the
Italian government for the exchange of certified emails.
1.2. Notational Conventions
1.2.1. Requirement Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [REQ].
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1.2.2. Acronyms
CMS: Cryptographic Message Syntax
CNIPA: Italian National Agency for Digital Administration
(Centro Nazionale per l'Informatica nella Pubblica
Amministrazione)
CNR: Italian National Research Council (Consiglio Nazionale
delle Ricerche)
CRL: Certificate Revocation List
CRL DP: Certificate Revocation List Distribution Point
DNS: Domain Name Service
DTD: Document Type Definition
FQDN: Fully Qualified Domain Name
ISTI: The Institute of Information Science and Technologies
at the CNR (Istituto di Scienza e Tecnologie
dell'Informazione "A.Faedo")
LDAP: Lightweight Directory Access Protocol
LDIF: LDAP Data Interchange Format
MIME: Multipurpose Internet Mail Extensions
PEC: Certified Electronic Mail (Posta Elettronica Certificata)
S/MIME: Secure/MIME
SMTP: Simple Mail Transfer Protocol
TLS: Transport Layer Security
XML: eXtensible Markup Language
1.2.3. Terminology and Definitions
Certification data: A set of data certified by the sender's PEC
provider that describes the original message. It includes: date and
time of dispatch, sender email address, recipient(s) email
address(es), subject, and message ID.
Certified electronic mail: A service based on electronic mail, as
defined by the [SMTP] standard and its extensions, which permits the
transmission of documents produced with informatics tools.
DigitPA: Ex-CNIPA.
Holder: The person or organization to whom a PEC mailbox is
assigned.
Message sent: A PEC message is considered sent when the sender's PEC
provider, after several checks, accepts the email and returns an
acceptance PEC notification to the sender.
Message received: A PEC message is considered received when it is
stored in the receiver's mailbox, after which the receiver PEC
provider returns a delivery PEC notification to the sender.
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Msgid: Is the message ID generated by the email client, as defined
in [EMAIL], before the message is submitted to the PEC system.
Ordinary mail: Non-PEC email messages.
Original message: Is the user-generated message before its arrival
to the sender access point. The original message is delivered to the
recipient inside a PEC transport envelope.
PEC domain: Corresponds to a DNS domain dedicated to the holders'
mailboxes.
PEC mailbox: An electronic mailbox for which delivery PEC
notifications are issued upon reception of PEC messages. Such a
mailbox can be defined exclusively within a PEC domain.
PEC msgid: Is a unique identifier generated by the PEC system, which
will substitute the msgid.
PEC provider: The entity that handles one or more PEC domains with
their relative points of access, reception, and delivery. It is the
holder of the key that is used for signing PEC notifications and
envelope, and it interacts with other PEC providers for
interoperability with other holders.
PEC provider's key: Is a key released by DigitPA to every PEC
provider. It is used to sign PEC notifications and envelopes, and to
authorize access to the PEC providers directory.
PEC providers directory: Is an LDAP server positioned in an area
reachable by all PEC service providers. It constitutes the technical
structure related to the public list of PEC service providers and
contains the list of PEC domains and service providers with relevant
certificates.
Service mailbox: A mailbox for the sole use of the provider,
dedicated for the reception of take in charge and virus detection
PEC notifications.
Time stamp: A digital evidence with which a temporal reference, that
can't be repudiated, is attributed to one or more documents.
2. PEC model
2.1. System-generated messages
The PEC system generates messages in MIME format composed of a
descriptive textual part and other [MIME1] parts, the number and
content of which varies according to the type of message generated.
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A system-generated message falls into one of the following
categories:
o Notifications;
o Envelopes.
The message is inserted in an S/MIME v3 structure in CMS format
and signed with the PEC provider's private key. The X.509v3
certificate associated with the key MUST be included in the
aforementioned structure. The S/MIME format used to sign system-
generated messages is the "multipart/signed" format (.p7s), as
described in section 3.4.3 of [SMIMEV3].
To guarantee the verifiability of signatures on as many mail clients
as possible, X.509v3 certificates used by certified email systems
MUST abide by the profile found in section 6.5.
In order for the receiving mail client to verify the signature,
the sender address MUST coincide with the one indicated within the
X.509v3 certificate. For this mechanism, PEC transport envelopes
MUST indicate in the "From:" field a single author's address which
is different from the one contained in the original message. To
allow for better message usability by the receiving user, the
author's mail address in the original message is inserted as a
"display name". For example, a "From:" field such as:
From: "John Smith" <john.smith@domain.example.com>
would result in the following "From:" value in the respective
PEC transport envelope:
From: "On behalf of: john.smith@domain.example.com"
<certified-mail@provider.example.com>
Both "From:" and "Sender:" fields MUST contain the same value. In
order for replies to be correctly sent back to the proper
destination, the "Reply-To:" field in the PEC transport envelope
MUST contain the same unaltered value of the original message's
"Reply-To:" field. When it is not explicitly specified in the
original message, the system that generates the PEC transport
envelope creates it by extracting the information from the "From:"
field in the original message.
When PEC notifications are sent, the system MUST use the original
message sender's address as the destination address, as is specified
in the reverse path data of the SMTP protocol. PEC notifications
MUST be sent to the sender's PEC mailbox without taking into account
the "Reply-To:" field, which might be present in the original
message's header.
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All system-generated PEC messages are identifiable for having a
specific header defined in PEC according to the type of message
generated.
To determine the certification data, the elements used for the
actual routing of the message are employed. In SMTP dialog phases,
the reverse path and forward path data ("MAIL FROM" and "RCPT TO"
commands) are thus considered certification data of both the sender
and the recipients respectively. Addressing data present in the
message body ("To:" and "Cc:" fields) are used solely in order to
discriminate between primary and carbon copy recipients when
necessary; addressing data present in the "Bcc:" field MUST be
considered invalid by the system.
2.1.1. Message types
All system-generated messages inherit their header fields and values
from the original message, with extra fields added according to the
type of message generated.
2.1.1.1. PEC notifications
They have the purpose of informing the sending user and interacting
providers of the progress the message is making within the PEC
network.
2.1.1.1.1. Success PEC notifications
Indicates an acknowledgment on the provider's side for the reception
or handling of a PEC message. More specifically, it can indicate one
of 3 situations: acceptance, take in charge, or delivery.
Added header fields are:
o X-Ricevuta
o X-Riferimento-Message-ID
The field "X-Ricevuta" (Notification) indicates the type of
PEC notification contained in the message, whereas "X-Riferimento-
Message-ID" (Reference Message-ID) contains the message ID generated
by the mail client.
Body contents differ according to notification type. This is
described more thoroughly in chapter 3.
o An acceptance PEC notification informs the user that his provider
has accepted the message and will be taking care of passing it on
to the provider(s) of the addressee(s).
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o A take in charge PEC notification is an inter-provider
communication only, it MUST NOT be sent to the users. With this
notification, the receiving provider simply informs the sending
one that it has received a PEC message, and will take the
responsibility of forwarding it to the addressee(s). From then on,
the sender provider is no longer held responsible as to the
whereabouts of the message, but is limited to notifying its user
of the success or failure of delivery.
o Delivery PEC notifications take place as the final communication
of a transaction, indicating overall success in handing the
message over to the addressee(s).
2.1.1.1.2. Delay PEC notifications
Delay PEC notifications are sent out 12 hours after a message has
been dispatched from the sending provider, and no take in charge or
delivery PEC notification was received. These have the sole purpose
of notifying the user of the delay.
If another 12 hours go by without any sign of a take in charge or
delivery PEC notification (amounting to a 24-hour delay), another
delay PEC notification is dispatched to the user informing him of
the possible delivery failure. The provider will not keep track of
the delay any further.
2.1.1.1.3. Failure PEC notifications
They are sent when there is some error in transmission or reception.
More specifically, a failure PEC notification can indicate either a
formal-exception error, or a virus detection.
Added header fields are:
o X-Ricevuta;
o X-Riferimento-Message-ID;
o X-VerificaSicurezza [optional]
"X-Ricevuta" (Notification) and "X-Riferimento-Message-ID"
(Reference Message-ID) have the same roles as indicated in section
2.1.1.1.1 (Success Notifications). "X-VerificaSicurezza" (Security
Verification) is an optional header field, used for virus-related
PEC notifications.
Body contents differ according to notification type. This is
described more thoroughly in chapter 3.
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2.1.1.2. PEC envelopes
Messages entering the PEC network are inserted within specific PEC
messages, called envelopes, before they are allowed to circulate
further within the network. These envelopes MUST inherit the
following header fields, along with their unmodified values, from
the message itself:
o Received
o To
o Cc
o Return-Path
o Reply-to (if present)
Depending on the type of message requesting admission into the PEC
network, it will be inserted either in a "Transport Envelope", or in
a "Anomaly Envelope". Distinction will be possible through the
addition of the "X-Transport" header field.
2.2. Basic structure
+-------------+ +------------+
| +--+ | | |
| |AP| | PEC | |
+----+ | +--+ | messages & | +---+ +--+ | +----+
|user|<-->| |<------------->| |InP| |DP| |<-->|user|
+----+ | +--+ +---+ | notifications | +---+ +--+ | +----+
| |DP| |InP| | | |
| +--+ +---+ | | |
+-------------+ +------------+
PEC PEC
sender receiver
provider provider
where:
AP = Access Point
DP = Delivery Point
InP = Incoming Point
2.2.1. Access point
This is what the user client at the sender side interacts with,
giving the user access to PEC services set up by the provider.
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Such access MUST be preceded by user authentication on the system
(see section 5.2). The access point receives the original messages
its user wishes to send, runs some formal checks, and acts according
to the outcome:
o if the message passes all checks, the access point generates an
acceptance PEC notification and inserts the original message
inside a PEC transport envelope;
o if a formal exception is detected, the access point refuses the
message and emits the relevant non-acceptance PEC notification
(see section 3.1.1);
o if a virus is detected, the access point generates a non-
acceptance PEC notification and inserts the original message as is
in the provider's special store.
Generation of the acceptance notification indicates to the user that
the message was accepted by the system, certifying also the date and
time of the event. The notification MUST contain user-readable text,
and an XML part containing the certification data.
The notification MAY also contain other attachments for extra
features offered by the provider.
Using the data available in the PEC providers directory (see section
4.5), the access point runs checks on every recipient in the "To:"
and "Cc:" fields present in the original message to verify whether
they belong to the PEC infrastructure or to non-PEC domains. Such
checks are done by verifying the existence, through a case
insensitive search, of the recipients' domains in the
"managedDomains" attribute found within the PEC providers directory.
Therefore, the acceptance PEC notification (and relevant
certification data) relates, for each address, the typology of its
domain; PEC or non-PEC.
The identifier (from now on PEC msgid) of accepted original messages
within the PEC infrastructure MUST be unambiguous in order to
consent correct tracking of messages and relative PEC notifications.
The format of such an identifier is:
[alphanumeric string]@[provider mail domain]
or:
[alphanumeric string]@[FQDN mail server]
Therefore, both the original message and the corresponding PEC
transport envelope MUST contain the following header field:
Message-ID: <[unique identifier]>
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When an email client that is interacting with the access point has
already inserted a Message ID (from now on msgid) in the original
message, that msgid SHALL be substituted by a PEC msgid. In order to
allow the sender to link the message sent with the relative
PEC notifications, the msgid MUST be inserted in the original
message as well as the relative PEC notifications and transport
envelope. If present, the msgid is REQUIRED in the original
message's header by adding the following header field:
X-Riferimento-Message-ID: <[original Message ID]>
which will also be inserted in the PEC transport envelope and
notifications, and related in the certification data (see section
4.4).
2.2.2. Incoming point
This point permits the exchange of PEC messages and notifications
between PEC providers. It is also the point through which ordinary
mail messages can be inserted within the system of certified mail.
The exchange of messages between providers takes place through
SMTP-based transactions, as defined in [SMTP]. If SMTP communication
errors occur, they MAY be handled using the standard error
notification mechanisms, as provided by SMTP in [SMTP] and
[SMTP-DSN]. The same mechanism is also adopted for handling
transitory errors, that result in long idling periods, during an
SMTP transmission phase. In order to guarantee that an error is
returned to the user as defined in section 3.3.3, the systems that
handles PEC traffic MUST adopt a time limit for message idleness
equal to 24 hours.
Once a message arrives, the incoming point runs the following list
of checks and operations:
o verifies correctness and type of the incoming message;
o if the incoming message is a correct and undamaged PEC transport
envelope:
- emits a take in charge PEC notification towards the sender
provider (section 3.2.1);
- forwards the PEC transport envelope to the delivery point
(section 3.3).
o if the incoming message is a correct and undamaged PEC
notification, forwards the notification to the delivery point.
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o if the incoming message does not conform to the prerequisites of a
correct and undamaged PEC transport envelope or notification, but
comes from a PEC provider, i.e. passes the verifications regarding
existence, origin, and validity of the signature, then the message
MUST be propagated towards the recipient.
Therefore, the incoming point:
- inserts the incoming message in an anomaly envelope (section
3.2.2);
- forwards the anomaly envelope to the delivery point.
o if the incoming message does not originate from a PEC system, i.e.
fails verifications regarding existence, origin, and validity of
the signature, then the message will be treated as ordinary email,
and, if propagated to the recipient:
- is inserted in an anomaly envelope (section 3.2.2);
- the anomaly envelope is forwarded to the delivery point.
The take in charge PEC notification is generated by the receiving
provider and sent to the sending provider. Its purpose is to keep
track of the message in its transition from one provider to another,
and is therefore strictly intra-provider communication; the end user
knows nothing about it.
To check the correctness and integrity of a PEC transport envelope
or notification, the incoming point runs the following tests:
o Signature existence - the system verifies the presence of an
S/MIME signature structure within the incoming message;
o Signature origin - the system verifies whether or not the
signature belongs to a PEC provider by extracting the certificate
used for signing and verifying its presence in the PEC providers
directory. To ease the check, it is possible to calculate the
certificate's [SHA1] hash value and perform a case-insensitive
search of its hexadecimal representation within the
"providerCertificateHash" attribute found in the PEC providers
directory. This operation allows to easily identify the sender
provider for subsequent and necessary matching checks between the
extracted certificate and the one present in the provider's
record;
o Signature validity - S/MIME signature correctness is verified by
recalculating the signature value, checking the entire
certification path, and verifying the [CRL] and temporal validity
of the certificate. In case some caching mechanism is used for CRL
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contents, an update interval MUST be adopted so that the most up-
to-date data is guaranteed, thus minimizing the possible delay
between a publication revocation by the Certification Authority
and the variation acknowledgment by the provider;
o Formal correctness - the provider performs sufficient and
necessary checks to guarantee that the incoming message is
compliant with the formats specified in this document (PEC
transport envelope and notifications).
If a virus-infected PEC transport envelope passes the checks just
mentioned it is still considered correct and undamaged. The presence
of the virus will be detected in a second phase, during which the
contents of the PEC transport envelope are verified. Thus, the
incoming point will refrain from forwarding the message to the
recipient, instead sending the appropriate PEC notification of non-
delivery and storing the virus-infected message in the provider's
special storage.
In case ordinary mail messages are received, the PEC provider SHALL
perform virus checks in order to prevent the infiltration of
potentially dangerous mail messages within the PEC system. If a
virus is detected in an ordinary mail message, the latter can be
discarded at the incoming point before it enters the PEC system.
In other words, no special treatment is reserved for the error, but
a handling that is conformant to the procedures usually followed for
messages going through the Internet.
When the receiving provider detects a virus inside a PEC transport
envelope during the reception phase, it emits a virus detection PEC
notification to the sending provider, which then realizes its checks
failed to detect that virus. When this happens, the sending provider
MUST:
o check what virus typologies were not detected by its own antivirus
to verify the possibility of interventions
o send a virus-induced non-delivery PEC notification to the sender's
mailbox.
2.2.3. Delivery point
Is the point that receives messages from the incoming point and
forwards them to the final recipient.
It MUST run a series of tests on received messages before forwarding
them to the user (see section 3.3.1). It first verifies the typology
of the message, and decides whether or not a PEC notification should
be issued to the sender. The delivery PEC notification (section
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3.3.2) is emitted after the message was delivered to the recipient's
PEC mailbox and only at reception of a valid PEC transport envelope
(sections 2.2.2 and 3.1.5).
In all other cases, such as anomaly envelopes and PEC notifications,
the delivery PEC notification is not emitted. Regardless, the
message received from the delivery point MUST be delivered
unmodified to the recipient's mailbox.
The delivery PEC notification indicates to the sender that the
message sent was in fact conveyed to the specified recipient's
mailbox, and certifies the date and time of delivery through use of
user-readable text and an XML part containing certification data,
along with other possible attachments added for extra features
offered by the provider.
If a PEC transport envelope received at the delivery point can't be
delivered to the destination mailbox, the delivery point emits a
non-delivery PEC notification (section 3.3.3). If, on the other
hand, the delivery error concerns a message that arrives from
Internet (i.e. a non-PEC message), no such notification is emitted.
2.2.4. Storage
Each provider MUST dedicate a special storage for the deposition
of any virus-infected messages encountered. Whether the virus be
detected by the sender's access point or the receiver's incoming
point, the provider that detects it MUST store the mail message in
its own storage, and keep it for 30 months.
2.2.5. Provider service mailbox
For exclusive use of the provider, dedicated to the reception of PEC
notifications in 2 cases only:
o take in charge notifications; and
o virus detection notification.
2.2.6. Provider service email address
Each provider MUST register a special purpose email address for use
when sending PEC transport envelopes and notifications, as
delineated in section 3. This address MAY conincide with that of the
service mailbox described in section 2.2.5.
2.3. Log
The server administrator MUST keep track of any and all operations
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carried out in a specific message log file. The information kept in
the log for each operation is the following:
o message ID (the value present in the Message-ID header field in
the original message)
o date and time of event
o sender of original message
o recipient(s) of original message
o subject of original message
o event type (reception, delivery, PEC notification emission, etc)
o Message-IDs of related generated messages
o sending provider
The service provider MUST store this data and preserve it
unmodified. Italian laws have specified that the service provider
retain the data for 30 months.
3. Message processing
3.1. Access point
The access point acts as a submission service as defined in
[SUBMISSION].
3.1.1. Formal checks on messages
When the access point receives a message the user wishes to send, it
MUST guarantee said message's formal conformity as defined in
[EMAIL], and verify that the:
o [EMAIL] header section contains a "From:" header field holding a
[EMAIL] compliant email address;
o [EMAIL] header section contains a "To:" header field holding one
or more [EMAIL] compliant email addresses;
o sender's address, specified in the SMTP reverse path, coincides
with the one in the message's "From:" header field;
o recipients' addresses specified in the SMTP forward path coincide
with the ones present in the "To:" or "Cc:" header fields of the
message;
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o "Bcc:" header field does not contain any value;
o total message size falls within the limits accepted by the
provider. Such limits apply depending on the number of recipients
as well; by multiplying it to the message size, the outcome MUST
fall within the limits accepted by the provider. Italian Laws have
specified this limit as being 30MB.
If the message does not pass the tests, the access point MUST NOT
accept the message within the PEC system, thus emitting the relative
PEC notification of non-acceptance.
3.1.2. Non-acceptance PEC notification due to formal exceptions
When the access point cannot forward the message received due to
failure in passing formal checks, the sender is notified of such an
outcome. If the error is caused by the message failing size checks,
a non-acceptance PEC notification is sent as long as the size
remains bound by a certain limit. If the size exceeds said limit,
error handling is left to SMTP.
The notification header will contain the following fields:
X-Ricevuta: non-accettazione
Date: [date of notification emission]
Subject: AVVISO DI NON ACCETTAZIONE: [original subject]
From: certified-mail@[mail domain]
To: [original sender]
X-Riferimento-Message-ID: [Message-ID of original message]
The notification body will contain a text part that constitutes the
actual notification in readable format according to a model that
relates the following information:
Error in message acceptance
On [date] at [time] ([time zone]), in the message "[subject]"
originating from "[original sender]" and addressed to:
[recipient_1]
[recipient_2]
.
.
[recipient_n]
a problem was detected which prevents its acceptance due to
[error description].
The message was not accepted.
Message identification: [Message-ID]
The same certification information is inserted in an XML file to be
added to the notification body, thus allowing automatic checks on
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the message (section 4.4). Parsing MUST be done on the XML part
only. Additional parts MAY be included by the provider for provider-
specific services. Regardless, the original message MUST NOT be
included. The message MUST follow the format described in section
4.3.
3.1.3. Non-acceptance PEC notification due to virus detection
The access point MUST run some tests on the content of messages it
receives from its users and reject them if a virus is detected. In
which case, a virus-detection-induced non-acceptance PEC
notification MUST be emitted to clearly inform the user of the
reason the message was refused.
The notification header contains the following fields:
X-Ricevuta: non-accettazione
X-VerificaSicurezza: errore
Date: [notification emission date]
Subject: AVVISO DI NON ACCETTAZIONE PER VIRUS: [original
subject]
From: certified-mail@[mail_domain]
To: [original sender]
X-Riferimento-Message-ID: [Message-ID of original message]
The body contains a readable text part according to the following
model:
Error in message acceptance due to virus presence
On [date] at [time] ([time zone]), in the message "[subject]"
originating from "[original sender]" and addressed to:
[recipient_1]
[recipient_2]
.
.
.
[recipient_n]
a security problem was detected [ID of detected content type].
The message was not accepted.
Message identification: [Message-ID]
The same certification data is inserted in an XML file added to the
notification to allow for automatic checks (section 4.4). Parsing
MUST be done on the XML part only. Additional parts MAY be
included by the provider for provider-specific services. Regardless,
the original message MUST NOT be included. The message MUST follow
the format described in section 4.3.
3.1.4. Acceptance PEC notification
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The acceptance PEC notification is a message sent to the sender,
containing date and time of acceptance, sender and recipient data,
and subject.
The header contains the following fields:
X-Ricevuta: accettazione
Date: [actual date of acceptance]
Subject: ACCETTAZIONE: [original subject]
From: certified-mail@[mail_domain]
To: [original sender]
X-Riferimento-Message-ID: [Message-ID of original message]
The message body contains a text part that constitutes the
notification in readable format, according to a model that relates
the following information:
Acceptance PEC notification
On [date] at [time] ([time zone]), the message "[subject]"
originating from "[original sender]" and addressed to:
[recipient_1] (["certified mail" | "ordinary mail"])
[recipient_2] (["certified mail" | "ordinary mail"])
.
.
.
[recipient_n] (["certified mail" | "ordinary mail"])
was accepted by the system and forwarded to the recipient(s).
Message identification: [Message-ID]
The same certification data is inserted in an XML file added to the
notification message, allowing automatic checks on it (section 4.4).
Parsing MUST be done on the XML part only. Additonal parts MAY be
included by the provider for provider-specific services. The message
MUST follow the format described in section 4.3.
3.1.5. PEC Transport envelope
A PEC transport envelope is a message generated by the access point
which contains the original message as well as certification data.
As mentioned in section 2.1.1.2, the PEC transport envelope inherits
from the original message the values of the following header fields,
which MUST be related unmodified:
o Received
o To
o Cc
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o Return-Path
o Reply-To (if present)
On the other hand, the following fields MUST be modified, or
inserted if necessary:
X-Trasporto: posta-certificata
Date: [actual date of acceptance]
Subject: POSTA CERTIFICATA: [original subject]
From: "On behalf of: [original sender]"
<certified-mail@[mail_domain]>
Reply-To: [original sender] (inserted only if not present)
Message-ID: [PEC message ID generated as explained in 2.2.1]
X-Riferimento-Message-ID: [message ID of original message]
X-TipoRicevuta: [completa/breve/sintetica]
The "X-TipoRicevuta" field indicates the type of delivery PEC
notification the sender wishes to receive - complete, brief, or
concise.
The body of the PEC transport envelope contains a text part that
constitutes the readable format of the message according to a model
that relates the following certification data:
Certified mail message
On [date] at [time] ([time zone]), the message "[subject]" was
sent by "[original sender]" and addressed to:
[recipient_1]
[recipient_2]
.
.
.
[recipient_n]
The original message is included in attachment.
Message identification: [Message-ID]
Within the PEC transport envelope, the entire, non-modified original
message is inserted in a [EMAIL]-compliant format (except for what
has been said regarding the Message ID), as well as an XML part
which contains the certification data that was already related in
text format, and information on the type of message and PEC
notification requested (section 4.4). Parsing MUST be done on the
XML part only. Additional parts MAY be included by the provider for
provider-specific services. The message MUST follow the format
described in section 4.3.
Note that the routing data of the PEC transport envelope (forward
and reverse paths) remain unaltered.
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3.1.6. Timeout delivery error PEC notification
If the sending provider doesn't receive a take in charge or
delivery PEC notification from the receiving provider within 12
hours after message dispatch, it informs the user that the
recipient's provider might not be able to deliver the message. In
case the sending provider doesn't receive a delivery PEC
notification within 24 hours after message dispatch, it emits
another non-delivery PEC notification to the user by the 24-hour
timeout, but not before 22 hours have passed.
Such a communication takes place through a PEC notification of non-
delivery due to timeout, the header of which contains the following
fields:
X-Ricevuta: preavviso-errore-consegna
Date: [date of notification emission]
Subject: AVVISO DI MANCATA CONSEGNA PER SUP. TEMPO MASSIMO:
[original subject]
From: certified-mail@[mail_domain]
To: [original recipient]
X-Riferimento-Message-ID: [Message-ID of original message]
The body of the first non-delivery PEC notification (12-hour
timeout) contains a text part that represents the readable format
of the notification which will relate the following data:
Non-delivery PEC notification
On [date] at [time] ([time zone]), the message
"[subject]" originating from "[original sender]"
and addressed to "[recipient]"
has not been delivered within the first 12 hours following
its dispatch. Not excluding that the message might eventually
be delivered, it is deemed useful to consider that dispatch
might not have a positive outcome. The system will see to
sending another non-delivery PEC notification if in the
following twelve hours no confirmation is received from the
recipient.
Message identification: [Message-ID]
On the other hand, 24-hour-timeout induced PEC notifications, which
have the same header as described above, will have the following
text in their body:
Non-delivery PEC notification
On [date] at [time] ([time zone]), the message
"[subject]" originating from "[original sender]"
and addressed to "[recipient]"
has not been delivered within 24 hours of its dispatch.
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The transaction is deemed to be considered terminated with a
negative outcome.
Massage identification: [Message-ID]
The same certification data is inserted in an XML file added to both
PEC notification types to allow automatic checks (section 4.4).
Parsing MUST be done on the XML part only. Additional parts MAY be
added for services supplied by the PEC provider. Regardless, the
original message MUST NOT be included. The message MUST follow the
format described in section 4.3.
A timeout PEC notification is generated if one of the following
scenarios occurs:
o the sending provider receives a take in charge PEC notification
during the first 12 hours following message dispatch, but does not
receive a delivery PEC notification at all. In this case it would
be a 24-hour timeout PEC notification.
o the sending provider does not receive a take in charge PEC
notification, but receives a delivery PEC notification after 12
hours and before the 24-hour timeout. In this case it would be a
12-hour timeout PEC notification.
o the sending provider doesn't receive either a take in charge nor a
delivery PEC notification. In this case 2 timeout PEC
notifications are generated; a 12-hour and a 24-hour timeout PEC
notification.
3.2. Incoming point
3.2.1. Take in charge PEC notification
When correct PEC transport envelopes (as defined in section 2.2.2.)
are exchanged between PEC providers, the receiver MUST send a take
in charge PEC notification to the sender. The single dispatched
notification concerns all recipients who belong to the same
provider, and to whom the incoming message was addressed, as stated
in the routing data (forward and reverse paths) of the SMTP
transaction. Within the certification data of a single take in
charge PEC notification, all recipients of the message to which it
refers are listed. In general, when receiving a PEC transport
envelope, each provider MUST emit one or more take in charge PEC
notifications to cover, in absence of SMTP transport errors, all the
recipients in its jurisdiction.
The header of a take in charge PEC notification contains the
following fields:
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X-Ricevuta: presa-in-carico
Date: [date of take in charge]
Subject: PRESA IN CARICO: [original subject]
From: certified-mail@[mail_domain]
To: [sender provider service mailbox]
X-Riferimento-Message-ID: [Message-ID of original message]
The provider's service email address is obtained from the PEC
providers directory during the necessary queries made in the
signature verification stage.
The body contains a text part that follows the underlying model:
take in charge PEC notification
On [date] at [time] ([time zone]), the message "[subject]"
originating from "[original sender]" and addressed to:
[recipient_1] (["certified mail" | "ordinary mail"])
[recipient_2] (["certified mail" | "ordinary mail"])
.
.
.
[recipient_n] (["certified mail" | "ordinary mail"])
was accepted by the system.
Message identification: [Message-ID]
The same certification data is inserted in an XML file which is
added to the notification message to allow for automatic checks
(section 4.4). Parsing MUST be done on the XML part only. Additional
parts MAY be added by the provider for provider-specific services.
The message MUST follow the format described in section 4.3.
3.2.2. Anomaly envelope
If the tests on an incoming message detect an error, or the message
is identified as being ordinary mail and the provider is set to
forward it to the recipient, the system MUST insert such a message
in an anomaly envelope. Before delivery, the entire message received
at the incoming point is inserted in an [EMAIL]-compliant format as
a [MIME1] part inside a new message that MUST inherit the unmodified
values for the following header fields from the received message:
o Received
o To
o Cc
o Return-Path
o Message-ID
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Whereas, the following header fields MUST be modified or inserted:
X-Trasporto: errore
Date: [message arrival date]
Subject: ANOMALIA MESSAGGIO: [original subject]
From: "On behalf of: [original sender]"
<certified-mail@[mail_domain]>
Reply-To: [original sender (inserted only if not already
present)]
The body contains a user-readable text part according to a model
that relates the following data:
Message anomaly
On [date] at [time] ([time zone]), the message "[subject]"
originating from "[original sender]" and addressed to:
[recipient_1]
[recipient_2]
.
.
.
[recipient_n]
was received.
The data has not been certified due to the following error:
[concise description of error]
The original message is attached.
Due to uncertainty regarding origin and/or conformity of the message
received, the anomaly envelope MUST NOT contain [MIME1] parts other
than the entire message that arrived at the incoming point.
Note that the routing data of such an envelope (forward and reverse
paths) remain unaltered. Doing so guarantees both message forwarding
to the recipients, and reception of SMTP error notifications, if any
occur, by the sender (as specified in [SMTP] & [SMTP-DSN]).
3.2.3. Virus detection PEC notification
If the incoming point receives virus-infected PEC messages, it MUST
NOT forward them. Rather it MUST inform the sending provider, which
will in turn inform the sending user, of the failed transmission.
A separate PEC notification of virus detection MUST be sent on
behalf of every recipient within the provider's domain.
In case a virus is detected during the reception phase of a message
whose origin was asserted through sender signature verification,
the system generates a virus-detected PEC notification indicating
the error found, and sends it to the sending provider's service
mailbox.
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The header of this PEC notification contains the following fields:
X-Ricevuta: rilevazione-virus
X-Sender: [original sender]
Date: [date of notification emission]
Subject: PROBLEMA DI SICUREZZA: [original subject]
From: certified-mail@[mail_domain]
To: [sender provider notifications]
X-Riferimento-Message-ID: [Message-ID of original message]
The body contains a readable text part according to a model that
relates the following data:
Virus detection PEC notification
On [date] at [time] ([time zone]), in the message "[subject]"
originating from "[original sender]" and addressed to
"[recipient]"
a security problem was detected [ID of content type detected].
Message identification: [Message-ID]
The same certification data is inserted in an XML file and added to
the notification to allow for automatic checks (section 4.4).
Parsing MUST be done on the XML part only. Additional parts MAY be
included by the provider for provider-specific services. Regardless,
the original message MUST NOT be included. The message MUST follow
the format described in section 4.3.
The message body MUST contain the reason for which the transmission
could not be completed.
3.2.4. Virus-induced delivery error PEC notification
At the reception of a virus detected PEC notification from the
receiving provider, the sender provider emits a non-delivery PEC
notification to the sending user.
The header for this notification contains the following fields:
X-Ricevuta: errore-consegna
X-VerificaSicurezza: errore
Date: [date of notification emission]
Subject: AVVISO DI MANCATA CONSEGNA PER VIRUS: [original
subject]
From: certified-mail@[mail_domain]
To: [original sender]
X-Riferimento-Message-ID: [Message-ID of original message]
The body is contains a readable text part according to a model that
relates the following data:
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Delivery error PEC notification due to virus
On [date] at [time] ([time zone]), in the message "[subject]"
addressed to "[recipient]"
a security problem was detected [ID of content type detected
by the anti-virus].
The message was not delivered.
Message identification: [Message-ID]
All the information necessary for the construction of such a PEC
notification can be obtained from the correlated virus-detected
PEC notification.
The same certification data is inserted in an XML file and added to
the notification message to allow for automatic checks (section
4.4). Parsing MUST be done on the XML part only. Additional parts
MAY be included by the provider for provider-specific services. The
reason the transaction was not completed MUST be specified in the
message, which MUST follow the format described in section 4.3.
3.3. Delivery point
3.3.1. Checks on incoming messages
When a message arrives at the delivery point, the system verifies:
O message type
O whether or not a PEC notification has to be returned.
3.3.2. Delivery PEC notification
A delivery PEC notification is issued only after a correct PEC
transport envelope (sections 2.2.2. and 3.1.5) has been delivered to
the recipient's mailbox.
In all other cases (e.g. anomaly envelopes, PEC notifications), the
delivery PEC notification is not issued. Regardless, the message
received at the delivery point MUST be delivered to the recipient's
mailbox unchanged.
This notification tells the user that his/her message has been
successfully delivered to the specified recipient. It includes
readable text that certifies the date and time of delivery, sender
and receiver data, and the subject. It also contains an XML
certification data file and other optional parts for functionalities
offered by the provider.
The following fields are inserted in the header:
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X-Ricevuta: avvenuta-consegna
Date: [delivery date]
Subject: CONSEGNA: [original subject]
From: certified-mail@[mail_domain]
To: [original sender]
X-Riferimento-Message-ID: [Message-ID of original message]
The value of the "X-TipoRicevuta" header field in the PEC transport
envelope is derived from the original message, thus allowing the
sender to determine the type of delivery PEC notification requested
from the primary recipients of the original message.
The notification MUST follow the format described in section 4.3.
3.3.2.1. Delivery PEC notification: complete
This is the default value for delivery PEC notifications. When no
value for the "X-TipoRicevuta" is specified, or when it contains the
value "complete", the system will require a complete delivery PEC
notification from addressees in the "To:" field, while a concise PEC
notification (section 3.3.2.3) will be required from those in the
"Cc:" field. The distinction between primary recipients and those
in carbon copy is done through an analysis of the "To:" and "Cc:"
fields. For PEC notifications sent on behalf of primary recipients,
a complete copy of the original message along with any attachments
is inserted in the notification. In case the system in charge of
delivery is not able to determine the recipient type due to
ambiguity problems in the "To:" and "Cc:" fields, delivery MUST be
considered as if addressed to a primary recipient and include the
complete copy of the original message.
The notification body contains a readable text part that relates
certifcation data according to the following model:
Delivery PEC notification
On [date] at [time] ([time zone]), the message "[subject]"
originating from "[original sender]" and addressed to
"[recipient]"
was placed in the destination's mailbox.
Message identification: [Message-ID]
The same certification data is inserted in an XML file and added to
the notification (section 4.4), along with any other parts that MAY
inserted by the provider for provider-specific services. Parsing
MUST be done on the XML part only. The delivery PEC notification
MUST be issued on behalf of every recipient of the message, and MUST
follow the format described in section 4.3.
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3.3.2.2. Delivery PEC notification: brief
In order to decrease the amount of data flowing, it is possible
for the sender to ask for a delivery PEC notification in "brief"
format. The brief delivery PEC notification contains the original
message and a ciphered hash value for each of its parts. The hash
value SHOULD be calculated on base64 encoded parts. As specified in
section 5.3, PEC messages MUST transit only on machines that belong
to the PEC network, and which MUST NOT alter the encoding of the
message during its transition/processing.
NOTE: Even though PEC uses these relaxed specifications, PEC
interoperability tests between over 20 service providers have never
revealed any problems. This is probably due to mail servers leaning
more towards leaving the messages they receive intact without
applying any changes. But issues might arise if a server decides to
modify encoded parts; for example, change the base64 line length,
whose hash value calculated at the receiver's end would then differ
from that at the sender's side.
To be able to verify the transmitted contents it is necessary for
the sender to keep the unaltered original copy of the part(s) to
which the hash values refer.
If the PEC transport envelope contains the header
X-TipoRicevuta: breve
the delivery point emits a brief delivery PEC notification on behalf
of the primary recipients, and a concise one (section 3.3.2.3) on
behalf of carbon copy recipients. The value of the header field in
the PEC transport envelope is derived from the original message.
The notification body contains a readable text part according to a
model that relates the following certification data:
Brief delivery PEC notification
On [date] at [time] ([time zone]), the message "[subject]"
originating from "[original sender]" and addressed to
"[recipient]"
was placed in the destination's mailbox.
Message identification: [Message-ID]
The same certification data is inserted in an XML file and added to
the notification (section 4.4), along with other parts which MAY be
included for specific provider-supplied services. Parsing MUST be
done on the XML part only.The delivery PEC notification is issued on
behalf of every recipient of the message, and MUST follow the format
described in section 4.3.
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The MIME structure of the original message is unaltered as it is
added to the notification, but each MIME part with a "name"
parameter in the header field "Content-Type," or a "filename"
parameter in the header field "Content-Disposition" MUST be
substituted by a text file containing that MIME part's hash value.
When the original message has an S/MIME format, it is necessary
not to alter the integrity of the message structure. Verification
of the S/MIME part in the original message takes place when the MIME
type of the top-level entity (which coincides with the message
itself) is checked. An S/MIME message MAY have the following MIME
types (as per [SMIMEV3]):
o multipart/signed
Represents an original message signed by the sender using the
structure described in [MIME-SECURE]. The message is made up of 2
MIME parts: the first is the message itself before the application
of the sender's signature, whereas the second contains signature
data. The second part (generally of type "application/pkcs7-
signature" or "application/x-pkcs-signature") contains data added
during the signing phase and MUST be left unchanged to avoid
compromising the overall message structure;
o "application/pkcs7-mime" or "application/x-pkcs7-mime"
The message is composed of a sole CMS object within the MIME part.
Given that attachments cannot be separated from the CMS object,
the MIME part is left intact (i.e., it is not replaced by the hash
value); therefore, the brief PEC notification is the same as the
complete PEC notification.
If the original message contains parts whose Content-Type is
"message/rfc822", i.e. contains an email message as attachment, the
entire attached message is substituted with its corresponding hash
value.
Therefore, when emitting a brief delivery PEC notification, the
provider MUST:
1. Identify and extract all the parts from the first MIME
part of the multipart/signed S/MIME message;
2. calculate the hash values of all the files attached by the sender
to the original message;
3. substitute originals with their hash values.
In general, in the case of original messages in S/MIME format, the
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copy of the message inserted within the brief delivery PEC
notification will have the following characteristics:
o if the original message is signed, the S/MIME structure and
signature-relative data will remain unchanged. The message will
generate an error in a future signature integrity verification
phase following the substitution of attachments with the
corresponding hash values.
o if the original message contains the "application/pkcs7-mime" or
"application/x-pkcs7-mime" MIME type, attachments present in the
message will not be substituted by their hash values, due to
impossibility of identification within a CMS structure.
The content of the brief delivery PEC notification will coincide
with that of a normal delivery PEC notification.
The algorithm used for hash calculation is the [SHA1], calculated on
the entire content of the part. To allow distinction between hash
files and the files to which they refer, the suffix ".hash" is added
to the original filename. The hash value is written in the file
using a hexadecimal representation as a single sequence of 40
characters. The MIME type of these attachments is set to
"text/plain" to highlight their textual nature.
3.3.2.3. Delivery PEC notification: concise
If the PEC transport envelope contains the header
X-TipoRicevuta: sintetica
the delivery point emits, both to primary and carbon copy
recipients, a concise delivery PEC notification that does not
contain the original message.
The message body of the notification contains a readable text part
according to a model that relates the following certification data:
Concise delivery PEC notification
On [date] at [time] ([time zone]), the message "[subject]"
originating from "[original sender]" and addressed to
"[recipient]"
was placed in the destination's mailbox.
Message identification: [Message-ID]
The same certification data is inserted within an XML file and
added to the notification (section 4.4), along with additional
parts that MAY be included for provider-specific services. Parsing
MUST be done on the XML part only. The notification is sent to each
one of the recipients to whom the message is delivered, and MUST
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follow the format described in section 4.3.
The concise delivery PEC notification follows the same emission
rules as the delivery PEC notification; added to it is only the XML
file containing the certification data, not the original message.
3.3.3. Non-delivery PEC notification
If an error occurs during the delivery of a correct PEC transport
message, the system returns to the sender a non-delivery PEC
notification that indicates the error condition.
The header will contain the following fields:
X-Ricevuta: errore-consegna
Date: [date of notification emission]
Subject: AVVISO DI MANCATA CONSEGNA: [original subject]
From: certified-mail@[mail_domain]
To: [original sender]
X-Riferimento-Message-ID: [Message-ID of original message]
The notification body contains a readable text part according to a
model that relates the following data:
Non-delivery PEC notification
On [date] at [time] ([time zone]), in the message "[subject]"
originating from "[original sender]" and addressed to
"[recipient]"
an error was detected.
The message was refused by the system.
Message identification: [Message-ID]
The same certification data is inserted within an XML file and
added to the notification in order to allow for automatic checks
(section 4.4). Parsing MUST be done on the XML part only. Additional
parts MAY be included by the PEC provider for provider-specific
services. The notification MUST follow the format described in
section 4.3.
3.4. Sender and receiver belonging to the same domain
PEC messages MUST be processed even if both sender and receiver(s)
belong to the same PEC domain.
3.5. Example: Complete transaction between 2 PEC domains
A correct transaction between two PEC domains goes through the
following steps:
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o The sending user sends an email to his provider's Access Point;
o The Access Point runs all checks and emits an acceptance PEC
notification to the user;
o The Access Point creates a PEC transport envelope and forwards it
to the Incoming Point of the receiving provider;
o The receiver's Incoming Point verifies the PEC transport envelope
and creates a take in charge PEC notification to be sent to the
sending provider;
o The sender's Incoming Point verifies the validity of the take in
charge PEC notification and forwards it to the Delivery Point;
o The sender's Delivery Point saves the take in charge PEC
notification in the provider's service mailbox;
o The receiver's Incoming Point forwards the PEC transport envelope
to the receiver's Delivery Point;
o The receiver's Delivery Point verifies the contents of the PEC
transport envelope and saves it in the recipient's mailbox;
o The receiver's Delivery Point creates a delivery PEC notification
and sends it to the sender's Incoming Point;
o The sender's Incoming Point verifies the validity of the delivery
PEC notification and forwards it to the sender's Delivery Point;
o The sender's Delivery Point saves the delivery PEC notification in
the sending user's mailbox;
o The receiving user has the message at his disposition.
NOTE: Some of these steps might occur in parallel, thus the
interaction might complete in a different order.
4. Formats
4.1. Temporal reference
For all operations carried out during message, notification, and
log elaboration processes by the access, incoming and delivery
points, it is necessary to have an accurate temporal reference
available. All events (generation of PEC notifications, transport
envelopes, logs, etc) that constitute the transaction of message
elaboration at the access, incoming, and delivery points MUST employ
a sole temporal value obtained from within the transaction itself.
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Doing this renders the instant of message elaboration unambiguous
within PEC logs, notifications, messages, etc, generated by the
server.
4.2. User date/time
Temporal indications supplied by the service in readable format
(text in PEC notifications, transport envelopes, etc) are provided
with reference to the legal time at the moment of the operation.
Following is the specification using the syntax description notation
definted in [ABNF].
date-fullyear = 4DIGIT
date-month = 2DIGIT ; 01-12
date-mday = 2DIGIT ; 01-28, 01-29, 01-30, 01-31 based on
; month/year
time-hour = 2DIGIT ; 00-23
time-minute = 2DIGIT ; 00-59
time-second = 2DIGIT ; 00-58, 00-59, 00-60 based on leap second
; rules
time-offset = "(" ("+" / "-") ")" time-hour ":" time-minute
partial-time = time-hour ":" time-minute ":" time-second
full-date = date-mday "/" date-month "/" date-fullyear
full-time = partial-time time-offset
NOTE: This specification follows the same restrictions as in section
5.7 of [TIMESTAMP].
4.3. Format of a PEC message body
This section describes the characteristics of the various components
of PEC messages and notifications generated by a PEC system. If one
of the message parts contains characters with values outside of the
range 0-127 (7-bit ASCII), that part will have to be adequately
encoded so that 7-bit transportation compatibility is guaranteed
(e.g. quoted-printable, base64 as per [MIME1]).
Before applying the signature, the message body has
Content-Type: multipart/mixed. Each part is described in the sections
below. The first part is the user readable text generated by the PEC
system, while the second and third parts are interchangeable in
order and contain the original message and the XML file for the
certification data.
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4.3.1. User readable text
Character set: ISO-8859-1 (Latin-1)
MIME type: text/plain or multipart/alternative
The multipart/alternative MIME type MAY be used to add an HTML
version of the body of system-generated messages. In this case, two
sub-parts MUST be present: one of type text/plain, the other
text/html. For the HTML part:
o it MUST contain the same information as related in the text part;
o it MUST NOT contain references to elements (e.g. images, sounds,
font, style sheets) neither internal to the message (added MIME
parts) nor external (e.g. hosted on the provider's server);
o MUST NOT have active content (e.g. JavaScript, VBscript, Plug-in,
ActiveX).
4.3.2. Original message
MIME type: message/rfc822
Attachment name: postacert.eml
4.3.3. Certification data
Character set: UTF-8
MIME type: application/xml
Attachment name: certdata.xml
4.4. Certification data scheme
Following is the DTD relative to the XML file that contains
certification data attached to PEC notifications.
<!--Use the element "postacert" as root-->
<!--"tipo" indicates the typology of the PEC message-->
<!--The attribute "errore" can have the following values-->
<!--"nessuno" = no error-->
<!--"no-dest" (with type="errore-consegna") = -->
<!-- wrong recipient-->
<!--"no-dominio" (with type="errore-consegna") = -->
<!-- wrong domain-->
<!--"virus" (with type="errore-consegna") = virus-->
<!--"virus" (with type="non-accettazione") = virus-->
<!--"altro" = generic error-->
<!ELEMENT postacert (intestazione, dati)>
<!ATTLIST postacert
tipo (accettazione |
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non-accettazione |
presa-in-carico |
avvenuta-consegna |
posta-certificata |
errore-consegna |
preavviso-errore-consegna |
rilevazione-virus) #REQUIRED
errore (nessuno |
no-dest |
no-dominio |
virus |
altro) "nessuno">
<!--Header of the original message-->
<!ELEMENT intestazione (mittente,
destinatari+,
risposte,
oggetto?)>
<!--Sender ("From" field) of the original message-->
<!ELEMENT mittente (#PCDATA)>
<!--Complete list of recipients ("To" and "Cc" fields)-->
<!--of the original message-->
<!--"tipo" indicates the typology of the recipient-->
<!ELEMENT destinatari (#PCDATA)>
<!ATTLIST destinatari
tipo (certificato | esterno) "certificato">
<!--Value of the "Reply-To" field of the original message-->
<!ELEMENT risposte (#PCDATA)>
<!--Value of the "Subject" field of the original message-->
<!ELEMENT oggetto (#PCDATA)>
<!--PEC message data-->
<!ELEMENT dati (gestore-emittente,
data,
identificativo,
msgid?,
ricevuta?,
consegna?,
ricezione*,
errore-esteso?)>
<!--Descriptive string of the provider that certifies -->
<!--the data-->
<!ELEMENT gestore-emittente (#PCDATA)>
<!--Date/time of message elaboration-->
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<!--"zona" is the difference between local time and UTC in -->
<!--"[+|-]hhmm" format-->
<!ELEMENT data (giorno, ora)>
<!ATTLIST data
zona CDATA #REQUIRED>
<!--Day in "dd/mm/yyyy" format-->
<!ELEMENT giorno (#PCDATA)>
<!--Local hour in "hh:mm:ss" format-->
<!ELEMENT ora (#PCDATA)>
<!--PEC msgid-->
<!ELEMENT identificativo (#PCDATA)>
<!--msgid of the original message before modifications-->
<!ELEMENT msgid (#PCDATA)>
<!--For PEC transport envelopes and delivery notifications-->
<!--indicate the type of PEC notification requested by the-->
<!--sender-->
<!ELEMENT ricevuta EMPTY>
<!ATTLIST ricevuta
tipo (completa |
breve |
sintetica ) #REQUIRED>
<!--For delivery, non-delivery, virus-induced non-delivery, -->
<!-- virus detection, and timeout PEC notifications-->
<!--Recipient address to which delivery has been carried -->
<!--out/tried-->
<!ELEMENT consegna (#PCDATA)>
<!--For take in charge PEC notifications-->
<!--recipients for whom it is the relative PEC notification-->
<!ELEMENT ricezione (#PCDATA)>
<!--In case of error-->
<!--brief description of the error-->
<!ELEMENT errore-esteso (#PCDATA)>
4.5. PEC providers directory scheme
The PEC providers directory is created through a centralized LDAP
server that contains the providers' data and their corresponding PEC
mail domains.
Following are the directory scheme's attributes:
- providerCertificateHash: hash of provider's certificate
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- providerCertificate: provider certificate
- providerName: provider name
- mailReceipt: provider reception email address
- managedDomains: managed domains
- LDIFLocationURL: provider LDIF record URL
- providerUnit: secondary operating environment name
The directory's base root is "o=postacert" and the
"DistinguishedName" of single records is of the type
"providerName=<name>, o=postacert". Search within the directory is
carried out mainly in case-sensitive mode using the
"providerCertificateHash" attribute (during envelope signature
verification phase) or the "managedDomains" attribute (during
message acceptance phase). It is possible for the record of a single
provider to contain multiple "providerCertificate" with the related
"providerCertificateHash" attributes in order to allow the handling
of the renewal of expiring certificates. The provider MUST make sure
to update its record with sufficient advance before the certificate
expiration date, by adding a new certificate whose validity overlaps
that of the previous one.
The data of all PEC providers is encompassed in a [LDIF] file which
is available as an [HTTPS] object, and can be found at the URL to
which the 'LDIFLocationURL' attribute in the "dn: o=postacert" record
points (see section 4.5.6). To guarantee authenticity, that file
MUST be signed by the provider for the operations regarding its PEC
services using the method described for single providers. The file,
the signature, and the X.509v3 certificate MUST be inserted in a
PKCS#7 structure in binary ASN.1 DER format as a file with ".p7m"
extension. The centralized [LDAP] system downloads that file on a
daily basis and, after suitable verifications of the signature,
applies it to the provider's record.
Through the [LDIF] file, single providers MUST keep a copy of the
directory locally, updated on a daily basis, in order to improve
system performance by avoiding continuous request dispatches to the
central system for every message elaboration phase.
If secondary environments are present, the [LDIF] file indicated in
the main environment's record MUST relate the contents of all the
provider-relevant records.
4.5.1. providerCertificateHash attribute
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The 'providerCertificateHash' attribute is a hexadecimal
representation of the hash in SHA1 format of the X.509v3
certificate used by the provider for PEC notifications and
envelope signatures.
( 1.3.6.1.4.1.16572.2.2.1 NAME 'providerCertificateHash'
DESC 'Hash SHA1 of X.509 certificate in hexadecimal format'
EQUALITY caseIgnoreIA5Match
SYNTAX 1.3.6.1.4.1.1466.115.121.1.26{40} )
The IA5String ( 1.3.6.1.4.1.1466.115.121.1.26 ) syntax is defined in
[LDAP-SYNTAXES].
4.5.2. providerCertificate attribute
The 'providerCertificate' attribute lists the certificate(s) used
by the provider to sign PEC notifications and transport envelopes.
( 1.3.6.1.4.1.16572.2.2.2 NAME 'providerCertificate'
DESC 'X.509 certificate in ASN.1 DER binary format'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.8 )
The Certificate Binary transfer ( 1.3.6.1.4.1.1466.115.121.1.8 )
syntax is defined in RFC 2252.
NOTE: By the time this draft is written, and after PEC had several
implementations up and running, RFC 2252 was rendered obsolete
by [LDAP-SYNTAXES], which removed the definition of the Binary
syntax (see [LDAP-SYNTAXES] Appendix B. point 12.).
4.5.3. providerName attribute
The 'providerName' attribute contains the name of the PEC provider.
All records MUST contain their provider's name in this attribute.
( 1.3.6.1.4.1.16572.2.2.3 NAME 'providerName'
DESC 'PEC provider'
EQUALITY caseIgnoreMatch
SUBSTR caseIgnoreSubstringsMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{32768}
SINGLE-VALUE )
The Directory String ( 1.3.6.1.4.1.1466.115.121.1.15 ) syntax is
defined in [LDAP-SYNTAXES].
4.5.4. mailReceipt attribute
The 'mailReceipt' attribute contains the provider's email address to
which take in charge and virus detection PEC notifications are sent.
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( 1.3.6.1.4.1.16572.2.2.4 NAME 'mailReceipt'
DESC 'E-mail address of the service mailbox'
EQUALITY caseIgnoreIA5Match
SUBSTR caseIgnoreIA5SubstringsMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.26{256}
SINGLE-VALUE )
The IA5String ( 1.3.6.1.4.1.1466.115.121.1.26 ) syntax is defined in
[LDAP-SYNTAXES].
4.5.5. managedDomains attribute
The 'managedDomains' attribute lists the PEC domains that are
handled by the provider.
( 1.3.6.1.4.1.16572.2.2.5 NAME 'managedDomains'
DESC 'Domains handled by the PEC provider'
EQUALITY caseIgnoreIA5Match
SUBSTR caseIgnoreIA5SubstringsMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 )
The IA5String ( 1.3.6.1.4.1.1466.115.121.26 ) syntax is defined in
[LDAP-SYNTAXES].
4.5.6. LDIFLocationURL attribute
The 'LDIFLocationURL' attribute contains an [HTTPS] URL that points
to the location of the [LDIF] file defining the provider's record.
When the attribute is present in the record "dn: o=postacert", then
it contains the definition of the entire directory in [LDIF] format.
Secondary environment records MUST NOT contain the 'LDIFLocationURL'
attribute which is obtained from the main environment's attributes
for all records connected to the provider.
( 1.3.6.1.4.1.16572.2.2.6 NAME 'LDIFLocationURL'
DESC 'URL of the LDIF file that defines the entry'
EQUALITY caseExactMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
SINGLE-VALUE )
The Directory String ( 1.3.6.1.4.1.1466.115.121.1.15 ) syntax is
defined in [LDAP-SYNTAXES].
4.5.7. providerUnit attribute
The 'providerUnit' attribute contains the name of secondary
operating environments - and attribute not present for the main
environment. It is possible for the provider to define several
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distinct records, each indicating a single, different secondary
operating environment, for which it is possible to declare specific
attributes that are, if need be, distinct from those relative to the
main and other environments.
The "DistinguishedName" of the records
relative to the secondary operating environments are of the type
"providerUnit=<environment>,providerName=<name>,o=postacert".
Every provider MUST have a record associated to its own main
environment, distinguishable for the absence of the "providerUnit"
attribute within the record and the DistinguishedName.
( 1.3.6.1.4.1.16572.2.2.7 NAME 'providerUnit'
DESC 'Name of the secondary operative environment'
EQUALITY caseIgnoreMatch
SUBSTR caseIgnoreSubstringsMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{32768}
SINGLE-VALUE )
The Directory String ( 1.3.6.1.4.1.1466.115.121.1.15 ) syntax is
definted in [LDAP-SYNTAXES].
4.5.8. LDIFLocationURLObject object class
The schema definition of the 'LDIFLocationURLObject' Object Class:
Name: LDIFLocationURLObject
Description: Class for the insertion of a LDIFLocationURL
attribute
OID: ( 1.3.6.1.4.1.16572.2.1.1 )
Kind: auxiliary
SubclassOf: top
MAY Contain: ( LDIFLocationURL )
4.5.9. provider object class
The schema definition of the 'provider' Object Class:
Name: provider
Description: PEC provider
OID: ( 1.3.6.1.4.1.16572.2.1.2 )
SubclassOf: top
MUST Contain: ( providerCertificateHash $
providerCertificate $
providerName $
mailReceipt $
managedDomains )
MAY Contain: ( description $
LDIFLocationURL $
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providerUnit )
4.5.10 LDIF file example
The following LDIF file represents an example of a providers'
directory, containing a base root and 2 fictitious providers. The
inserted certificates are two self-signed certificates used for
example purposes only:
dn: o=postacert
objectclass: top
objectclass: organization
objectClass: LDIFLocationURLObject
o: postacert
LDIFLocationURL: https://igpec.rupa.example.com/igpec.ldif.p7m
description: Base root for the PEC providers directory
dn: providerName=Anonymous Certified Mail S.p.A.,o=postacert
objectclass: top
objectclass: provider
providerName: Anonymous Certified Mail S.p.A.
providerCertificateHash:
7E7AEF1059AE0F454F2643A95F69EC3556009239
providerCertificate;binary::
MIIDBjCCAm+gAwIBAgIBADANBgkqhkiG9w0BAQQFADBmMQswCQYDVQQGEw
JJVDEpMCcGA1UEChMgQW5vbmltYSBQb3N0YSBDZXJ0aWZpY2F0YSBTLnAu
QS4xLDAqBgkqhkiG9w0BCQEWHXBvc3RhLWNlcnRpZmljYXRhQGFucG9jZX
J0Lml0MB4XDTAyMTIwOTE3MjQxNVoXDTAzMTIwOTE3MjQxNVowZjELMAkG
A1UEBhMCSVQxKTAnBgNVBAoTIEFub25pbWEgUG9zdGEgQ2VydGlmaWNhdG
EgUy5wLkEuMSwwKgYJKoZIhvcNAQkBFh1wb3N0YS1jZXJ0aWZpY2F0YUBh
bnBvY2VydC5pdDCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEAr8J+qK
KdxV9LzDMPqwnEy0P8H/KwbI0Szs8p6UZajZdpeUK0Ncbrv1QyXZNNtSMC
2uL09HDyx8agjgZWdhypnehguiSK3busha15RSpMGhiqxmz2b0HhOG73Gf
alZelqrwqmElna4MNUaLhbOvTd/sqPUS378w5IaIhWxzy34XcCAwEAAaOB
wzCBwDAdBgNVHQ4EFgQUN8lC0znQWEs0xspZ/aBzsaGvRZMwgZAGA1UdIw
SBiDCBhYAUN8lC0znQWEs0xspZ/aBzsaGvRZOhaqRoMGYxCzAJBgNVBAYT
AklUMSkwJwYDVQQKEyBBbm9uaW1hIFBvc3RhIENlcnRpZmljYXRhIFMucC
5BLjEsMCoGCSqGSIb3DQEJARYdcG9zdGEtY2VydGlmaWNhdGFAYW5wb2Nl
cnQuaXSCAQAwDAYDVR0TBAUwAwEB/zANBgkqhkiG9w0BAQQFAAOBgQA58B
Z+q1qSKpuffzTBpMtbeFkDIxMqMa+ycnxdMNvcWgCm1A9ZiFJsvqYhDDqA
XxfHjkrzXuSZkYq6WiQCsLp0aYVy40QCIwbOunhrvsxh3vsG5CgN76JzZ9
5Z/1OCFNhLfqf1VH2NSS8TaYCCi/VO7W1Q1KkcA2VlxlQP7McSUw==
mailReceipt: ricevute@anpocert.example.com
LDIFLocationURL: https://anpocert.example.com/anpocert.ldif.p7m
managedDomains: mail.anpocert.example.com
managedDomains: cert.company.example.com
managedDomains: costmec.example.com
description: Certified mail services for companies
dn: providerName=Postal Services S.p.A,o=postacert
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objectclass: top
objectclass: provider
providerName: Postal Services S.p.A
providerCertificateHash:
e00fdd9d88be0e2cc766b893315caf93d5701a6a
providerCertificate;binary::
MIIDHjCCAoegAwIBAgIBADANBgkqhkiG9w0BAQQFADBuMQswCQYDVQQGEw
JJVDEfMB0GA1UEChMWU2Vydml6aSBQb3N0YWxpIFMuci5sLjEPMA0GA1UE
CxMGRC5DLkMuMS0wKwYJKoZIhvcNAQkBFh5wb3N0YS1jZXJ0aWZpY2F0YU
BzZXJwb3N0YWwuaXQwHhcNMDIxMjA5MTczMjE2WhcNMDMxMjA5MTczMjE2
WjBuMQswCQYDVQQGEwJJVDEfMB0GA1UEChMWU2Vydml6aSBQb3N0YWxpIF
Muci5sLjEPMA0GA1UECxMGRC5DLkMuMS0wKwYJKoZIhvcNAQkBFh5wb3N0
YS1jZXJ0aWZpY2F0YUBzZXJwb3N0YWwuaXQwgZ8wDQYJKoZIhvcNAQEBBQ
ADgY0AMIGJAoGBAKoc7n6zA+sO8NATMcfJ+U2aoDEsrj/cObG3QAN6Sr+l
ygWxYXLBZNfSDWqL1K4edLr4gCZIDFsq0PIEaYZhYRGjhbcuJ9H/ZdtWdX
xcwEWN4mwFzlsASogsh5JeqS8db3A1JWkvhO9EUfaCYk8YMAkXYdCtLD9s
9tCYZeTE2ut9AgMBAAGjgcswgcgwHQYDVR0OBBYEFHPw7VJIoIM3VYhuHa
eAwpPF5leMMIGYBgNVHSMEgZAwgY2AFHPw7VJIoIM3VYhuHaeAwpPF5leM
oXKkcDBuMQswCQYDVQQGEwJJVDEfMB0GA1UEChMWU2Vydml6aSBQb3N0YW
xpIFMuci5sLjEPMA0GA1UECxMGRC5DLkMuMS0wKwYJKoZIhvcNAQkBFh5w
b3N0YS1jZXJ0aWZpY2F0YUBzZXJwb3N0YWwuaXSCAQAwDAYDVR0TBAUwAw
EB/zANBgkqhkiG9w0BAQQFAAOBgQApqeXvmOyEjwhMrXezPAXELMZwv4qq
r5ri4XuxTq6sS9jRsEbZrS+NmbcJ7S7eFwNQMNxYFVJqdWoLh8qExsTLXn
sKycSnHbCfuphrKvXjQvR2da75U4zGSkroiyvJ2s9TtiCcT3lQtIjmvrFb
aSBiyzj+za7foFUCQmxCLtDaA==
mailReceipt: takecharge@postalser.example.com
LDIFLocationURL: https://postalser.example.com/ldif.txt.p7m
managedDomains: postal-services.example.com
managedDomains: receivedmail.example.com
description: Certified mail services for the public
The following LDIF file represents an example of a PEC providers'
directory, containing a base root and 2 fictitious providers, the
first of which handles a secondary environment as well. The
certificates inserted are 2 self-signed certificates used for
example purposes only:
dn: o=postacert
objectclass: top
objectclass: organization
objectClass: LDIFLocationURLObject
o: postacert
LDIFLocationURL: https://igpec.rupa.example.com/igpec.ldif.p7m
description: Base root for the PEC providers directory
dn: providerName=Anonymous Certified Mail S.p.A.,o=postacert
objectclass: top
objectclass: provider
providerName: Anonymous Certified Mail S.p.A.
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providerCertificateHash:
7E7AEF1059AE0F454F2643A95F69EC3556009239
providerCertificate;binary::
MIIDBjCCAm+gAwIBAgIBADANBgkqhkiG9w0BAQQFADBmMQswCQYDVQQGEw
JJVDEpMCcGA1UEChMgQW5vbmltYSBQb3N0YSBDZXJ0aWZpY2F0YSBTLnAu
QS4xLDAqBgkqhkiG9w0BCQEWHXBvc3RhLWNlcnRpZmljYXRhQGFucG9jZX
J0Lml0MB4XDTAyMTIwOTE3MjQxNVoXDTAzMTIwOTE3MjQxNVowZjELMAkG
A1UEBhMCSVQxKTAnBgNVBAoTIEFub25pbWEgUG9zdGEgQ2VydGlmaWNhdG
EgUy5wLkEuMSwwKgYJKoZIhvcNAQkBFh1wb3N0YS1jZXJ0aWZpY2F0YUBh
bnBvY2VydC5pdDCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEAr8J+qK
KdxV9LzDMPqwnEy0P8H/KwbI0Szs8p6UZajZdpeUK0Ncbrv1QyXZNNtSMC
2uL09HDyx8agjgZWdhypnehguiSK3busha15RSpMGhiqxmz2b0HhOG73Gf
alZelqrwqmElna4MNUaLhbOvTd/sqPUS378w5IaIhWxzy34XcCAwEAAaOB
wzCBwDAdBgNVHQ4EFgQUN8lC0znQWEs0xspZ/aBzsaGvRZMwgZAGA1UdIw
SBiDCBhYAUN8lC0znQWEs0xspZ/aBzsaGvRZOhaqRoMGYxCzAJBgNVBAYT
AklUMSkwJwYDVQQKEyBBbm9uaW1hIFBvc3RhIENlcnRpZmljYXRhIFMucC
5BLjEsMCoGCSqGSIb3DQEJARYdcG9zdGEtY2VydGlmaWNhdGFAYW5wb2Nl
cnQuaXSCAQAwDAYDVR0TBAUwAwEB/zANBgkqhkiG9w0BAQQFAAOBgQA58B
Z+q1qSKpuffzTBpMtbeFkDIxMqMa+ycnxdMNvcWgCm1A9ZiFJsvqYhDDqA
XxfHjkrzXuSZkYq6WiQCsLp0aYVy40QCIwbOunhrvsxh3vsG5CgN76JzZ9
5Z/1OCFNhLfqf1VH2NSS8TaYCCi/VO7W1Q1KkcA2VlxlQP7McSUw==
mailReceipt: notifications@anpocert.it.example
LDIFLocationURL: http://anpocert.example.com/anpocert.ldif.p7m
managedDomains: mail.anpocert.example.com
managedDomains: cert.company.example.com
managedDomains: costmec.example.com
description: Certified mail services for companies
dn: providerUnit=Secondary Environment, providerName=Anonymous
Certified Mail S.p.A.,o=postacert
objectclass: top
objectclass: provider
providerName: Certified Mail S.p.A.
providerUnit: Secondary Environment
providerCertificateHash:
7E7AEF1059AE0F454F2643A95F69EC3556009239
providerCertificate;binary::
MIIDBjCCAm+gAwIBAgIBADANBgkqhkiG9w0BAQQFADBmMQswCQYDVQQGEw
JJVDEpMCcGA1UEChMgQW5vbmltYSBQb3N0YSBDZXJ0aWZpY2F0YSBTLnAu
QS4xLDAqBgkqhkiG9w0BCQEWHXBvc3RhLWNlcnRpZmljYXRhQGFucG9jZX
J0Lml0MB4XDTAyMTIwOTE3MjQxNVoXDTAzMTIwOTE3MjQxNVowZjELMAkG
A1UEBhMCSVQxKTAnBgNVBAoTIEFub25pbWEgUG9zdGEgQ2VydGlmaWNhdG
EgUy5wLkEuMSwwKgYJKoZIhvcNAQkBFh1wb3N0YS1jZXJ0aWZpY2F0YUBh
bnBvY2VydC5pdDCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEAr8J+qK
KdxV9LzDMPqwnEy0P8H/KwbI0Szs8p6UZajZdpeUK0Ncbrv1QyXZNNtSMC
2uL09HDyx8agjgZWdhypnehguiSK3busha15RSpMGhiqxmz2b0HhOG73Gf
alZelqrwqmElna4MNUaLhbOvTd/sqPUS378w5IaIhWxzy34XcCAwEAAaOB
wzCBwDAdBgNVHQ4EFgQUN8lC0znQWEs0xspZ/aBzsaGvRZMwgZAGA1UdIw
SBiDCBhYAUN8lC0znQWEs0xspZ/aBzsaGvRZOhaqRoMGYxCzAJBgNVBAYT
AklUMSkwJwYDVQQKEyBBbm9uaW1hIFBvc3RhIENlcnRpZmljYXRhIFMucC
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5BLjEsMCoGCSqGSIb3DQEJARYdcG9zdGEtY2VydGlmaWNhdGFAYW5wb2Nl
cnQuaXSCAQAwDAYDVR0TBAUwAwEB/zANBgkqhkiG9w0BAQQFAAOBgQA58B
Z+q1qSKpuffzTBpMtbeFkDIxMqMa+ycnxdMNvcWgCm1A9ZiFJsvqYhDDqA
XxfHjkrzXuSZkYq6WiQCsLp0aYVy40QCIwbOunhrvsxh3vsG5CgN76JzZ9
5Z/1OCFNhLfqf1VH2NSS8TaYCCi/VO7W1Q1KkcA2VlxlQP7McSUw==
mailReceipt: notifications@secondary.anpocert.example.com
managedDomains: management.anpocert.example.com
managedDomains: personnel.anpocert.example.com
description: Corporate internal services
dn: providerName=Postal Services S.r.l.,o=postacert
objectclass: top
objectclass: provider
providerName: Postal Services S.r.l.
providerCertificateHash:
e00fdd9d88be0e2cc766b893315caf93d5701a6a
providerCertificate;binary::
MIIDHjCCAoegAwIBAgIBADANBgkqhkiG9w0BAQQFADBuMQswCQYDVQQGEw
JJVDEfMB0GA1UEChMWU2Vydml6aSBQb3N0YWxpIFMuci5sLjEPMA0GA1UE
CxMGRC5DLkMuMS0wKwYJKoZIhvcNAQkBFh5wb3N0YS1jZXJ0aWZpY2F0YU
BzZXJwb3N0YWwuaXQwHhcNMDIxMjA5MTczMjE2WhcNMDMxMjA5MTczMjE2
WjBuMQswCQYDVQQGEwJJVDEfMB0GA1UEChMWU2Vydml6aSBQb3N0YWxpIF
Muci5sLjEPMA0GA1UECxMGRC5DLkMuMS0wKwYJKoZIhvcNAQkBFh5wb3N0
YS1jZXJ0aWZpY2F0YUBzZXJwb3N0YWwuaXQwgZ8wDQYJKoZIhvcNAQEBBQ
ADgY0AMIGJAoGBAKoc7n6zA+sO8NATMcfJ+U2aoDEsrj/cObG3QAN6Sr+l
ygWxYXLBZNfSDWqL1K4edLr4gCZIDFsq0PIEaYZhYRGjhbcuJ9H/ZdtWdX
xcwEWN4mwFzlsASogsh5JeqS8db3A1JWkvhO9EUfaCYk8YMAkXYdCtLD9s
9tCYZeTE2ut9AgMBAAGjgcswgcgwHQYDVR0OBBYEFHPw7VJIoIM3VYhuHa
eAwpPF5leMMIGYBgNVHSMEgZAwgY2AFHPw7VJIoIM3VYhuHaeAwpPF5leM
oXKkcDBuMQswCQYDVQQGEwJJVDEfMB0GA1UEChMWU2Vydml6aSBQb3N0YW
xpIFMuci5sLjEPMA0GA1UECxMGRC5DLkMuMS0wKwYJKoZIhvcNAQkBFh5w
b3N0YS1jZXJ0aWZpY2F0YUBzZXJwb3N0YWwuaXSCAQAwDAYDVR0TBAUwAw
EB/zANBgkqhkiG9w0BAQQFAAOBgQApqeXvmOyEjwhMrXezPAXELMZwv4qq
r5ri4XuxTq6sS9jRsEbZrS+NmbcJ7S7eFwNQMNxYFVJqdWoLh8qExsTLXn
sKycPSnHbCfuphrKvXjQvR2da75U4zGSkroiyvJ2s9TtiCcT3lQtIjmvrF
baSBiyzj+za7foFUCQmxCLtDaA==
mailReceipt: takecharge@postalser.example.com
LDIFLocationURL: http://postalser.example.com/ldif.txt.p7m
managedDomains: postal-services.example.com
managedDomains: receivedmail.example.com
description: Certified mail services for the public
5. Security-related aspects
5.1. Digital signature
It is recommended that a dedicated hardware module be used to handle
private key and signature operations, the specifications of which
are outside the scope of this document. It's up to the PEC providers
to conform to security requisites expected for the service.
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5.2. Authentication
User access to PEC services through the access point MUST be allowed
only upon successful user authentication on the system.
For example, authentication might use user-ID and password, or, if
available and considered necessary for the type of service provided,
an electronic ID card or the national services card. Choice of
authentication method is left to the better judgment of the service
provider. Authentication is necessary to guarantee as much as
possible that the message is sent by a PEC user whose identification
data is congruent with the specified sender, so as to avoid
falsification of the latter.
5.3. Secure interaction
To guarantee that the original message remains unaltered during
transaction, envelopment and signature are applied on outgoing
messages at the access point, and subsequent verification of
incoming messages is done at the incoming point.
All communications within the PEC network MUST use secure channels.
Integrity and confidentiality of connections between PEC provider
and user MUST be guaranteed through the use of secure protocols,
such as those based on [TLS] and those that create a secure
transport channel on which non-secure protocols can transmit (e.g.
IPSec).
The interaction between providers MUST take place using SMTP on
[TLS], as per [SMTP-TLS]. The incoming point MUST provide and
announce its support for the STARTTLS extension, as well as accept
both unencrypted connections (for ordinary mail) and protected ones.
To guarantee complete traceability in the flow of PEC messages,
these MUST NOT transit on systems external to the PEC network. When
exchanging messages between different providers, all transactions
MUST take place between machines that belong to the PEC network or
are directly managed by the provider. An "MX" type record MAY be
associated to each PEC domain defined within the system for name
resolution, in which case secondary reception systems specified in
that record MUST be under direct control of the provider. All in
conformance with [SMTP].
5.4. Virus
Another important security aspect that concerns the PEC system, is
related to the technical and functional architecture which MUST
block the presence of viruses from endangering the security of all
handled messages. It is therefore REQUIRED to have installations and
continuous updates of anti-virus systems that hinder infections as
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much as possible without intervening on the content of the certified
mail, in compliance with what has been discussed thus far.
5.5. S/MIME certificate
In this document the S/MIME certificate profile is defined for use
in the certification of PEC messages done by the providers. The
proposed profile of the S/MIME certificate is based on the IETF
standards [SMIMECERT] and [CRL], which in turn are based on the
standard ISO/IEC 9594-8:2001.
5.5.1. Provider-related information (subject)
The information related to the PEC provider holder of the
certificate MUST be inserted in the "Subject:" field (Subject DN).
More precisely, the Subject DN MUST contain the PEC provider's name
as it is in the "providerName" attribute published in the PEC
providers directory (section 4.5), but the Subject DN does not have
to match the Provider entry DN in the LDIF. The providerName MUST be
present in the CommonName or OrganizationName attributes of the
Subject field in the certificate.
Certificates MUST contain an Internet mail address, which MUST
have a value in the subjectAltName extension, and SHOULD NOT be
present in the Subject Distinguished Name.
Valid subjectDN are:
C=IT, O=AcmePEC S.p.A, CN=Posta Certificata
C=IT, O=ServiziPEC S.p.A, CN=Posta Certificata
Valorization of other attributes in the Subject DN, if present,
MUST be done in compliance with [CRL].
5.5.2. Certificate extensions
Extensions that MUST be present in the S/MIME certificate are:
o Key Usage
o Authority Key Identifier
o Subject Key Identifier
o Subject Alternative Name
The Basic Constraints extension (Object ID:2.5.29.19) MUST NOT be
present.
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The valorization of the above listed extensions for the described
profile follows.
The Key Usage extension (Object ID: 2.5.29.15) MUST have the
digitalSignature bit (bit 0) activated and MUST be marked as
critical. The extension MAY contain other active bits corresponding
to different Key Usage, as long as that doesn't contrast with the
indications in [CRL].
The Authority Key Identifier (Object ID:2.5.29.35) MUST contain
at least the keyIdentifier field, and MUST NOT be marked as
critical.
The Subject Key Identifier extension (Object ID: 2.5.29.14) MUST
contain at least the keyIdentifier field, and MUST NOT be marked as
critical.
The Subject Alternative Name (Object ID: 2.5.29.17) MUST contain
at least the rfc822Name field, and MUST NOT be marked as critical.
Adding other extensions that have not been described in this
document is to be considered OPTIONAL, as long as it remains
compliant with [CRL]; such added extension MUST NOT be marked as
critical.
5.5.3. Example
Following is an example of an S/MIME certificate compliant with
the minimal requisites described in this profile. Values used are
of fictitious providers generated for example purposes only.
5.5.3.1. General-use certificate in annotated version
An asterisk near the label of an extension means that such an
extension has been marked as critical.
VERSION: 3
SERIAL: 11226 (0x2bda)
INNER SIGNATURE:
ALG. ID: id-sha1-with-rsa-encryption
PARAMETER: 0
ISSUER:
Country Name: IT
Organization Name: Certifier 1
Organizational Unit Name: Certification Service Provider
Common Name: Certifier S.p.A.
VALIDITY:
Not Before: Oct 5, 04 09:04:23 GMT
Not After: Oct 5, 05 09:04:23 GMT
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SUBJECT:
Country Name: IT
Organization Name: AcmePEC S.p.A.
Common Name: Certified Mail
PUBLIC KEY: (key size is 1024 bits)
ALGORITHM:
ALG. ID: id-rsa-encryption
PARAMETER: 0
MODULUS: 0x00afbeb4 5563198a aa9bac3f 1b29b5be
7f691945 89d01569 ca0d555b 5c33d7e9
...
d15ff128 6792def5 b3f884e6 54b326db
cf
EXPONENT: 0x010001
EXTENSIONS:
Subject Alt Name:
RFC Name: posta-certificata@acmepec.it
Key Usage*: Digital Signature
Authority Key Identifier: 0x12345678 aaaaaaaa bbbbbbbb
cccccccc dddddddd
Subject Key Identifier: 0x3afae080 6453527a 3e5709d8 49a941a8
a3a70ae1
SIGNATURE:
ALG. ID: id-sha1-with-rsa-encryption
PARAMETER: 0
VALUE: 0x874b4d25 70a46180 c9770a85 fe7923ce
b22d2955 2f3af207 142b2aba 643aaa61
...
d8fd10b4 c9e00ebc c089f7a3 549a1907
ff885220 ce796328 b0f8ecac 86ffb1cc
5.5.3.2. General-use certificate in dump asn.1
0 30 794: SEQUENCE {
4 30 514: SEQUENCE {
8 A0 3: [0] {
10 02 1: INTEGER 2
: }
13 02 2: INTEGER 11226
17 30 13: SEQUENCE {
19 06 9: OBJECT IDENTIFIER
: sha1withRSAEncryption (1 2 840 113549 1 1 5)
30 05 0: NULL
: }
32 30 101: SEQUENCE {
34 31 11: SET {
36 30 9: SEQUENCE {
38 06 3: OBJECT IDENTIFIER countryName (2 5 4 6)
43 13 2: PrintableString 'IT'
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: }
: }
47 31 28: SET {
49 30 26: SEQUENCE {
51 06 3: OBJECT IDENTIFIER organizationName (2 5 4 10)
56 13 19: PrintableString 'Certificatore 1'
: }
: }
77 31 22: SET {
79 30 20: SEQUENCE {
81 06 3: OBJECT IDENTIFIER organizationalUnitName (2 5 4 11)
86 13 13: PrintableString 'Certification Service Provider'
: }
: }
101 31 32: SET {
103 30 30: SEQUENCE {
105 06 3: OBJECT IDENTIFIER commonName (2 5 4 3)
110 13 23: PrintableString 'Certificatore S.p.A.'
: }
: }
: }
135 30 30: SEQUENCE {
137 17 13: UTCTime '041005090423Z'
152 17 13: UTCTime '051005090423Z'
: }
167 30 66: SEQUENCE {
169 31 11: SET {
171 30 9: SEQUENCE {
173 06 3: OBJECT IDENTIFIER countryName (2 5 4 6)
178 13 2: PrintableString 'IT'
: }
: }
182 31 23: SET {
184 30 21: SEQUENCE {
186 06 3: OBJECT IDENTIFIER organizationName (2 5 4 10)
191 13 14: PrintableString 'AcmePEC S.p.A.'
: }
: }
207 31 26: SET {
209 30 24: SEQUENCE {
211 06 3: OBJECT IDENTIFIER commonName (2 5 4 3)
216 13 17: PrintableString 'Posta Certificata'
: }
: }
: }
235 30 159: SEQUENCE {
238 30 13: SEQUENCE {
240 06 9: OBJECT IDENTIFIER rsaEncryption (1 2 840 113549
1 1 1)
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251 05 0: NULL
: }
253 03 141: BIT STRING 0 unused bits
: 30 81 89 02 81 81 00 AF BE B4 55 63 19 8A AA 9B
: AC 3F 1B 29 B5 BE 7F 69 19 45 89 D0 15 69 CA 0D
: 55 5B 5C 33 D7 E9 C8 6E FC 14 46 C3 C3 09 47 DD
: CD 10 74 1D 76 4E 71 14 E7 69 42 BE 1C 47 61 85
: 4D 74 76 DD 0B B5 78 4F 1E 84 DD B4 86 7F 96 DF
: 5E 7B AF 0E CE EA 12 57 0B DF 9B 63 67 4D F9 37
: B7 48 35 27 C2 89 F3 C3 54 66 F7 DA 6C BE 4F 5D
: 85 55 07 A4 97 8C D1 5F F1 28 67 92 DE F5 B3 F8
: [ Another 12 bytes skipped ]
: }
397 A3 123: [3] {
399 30 121: SEQUENCE {
401 30 39: SEQUENCE {
403 06 3: OBJECT IDENTIFIER subjectAltName (2 5 29 17)
408 04 32: OCTET STRING
: 30 1E 81 1C 70 6F 73 74 61 2D 63 65 72 74 69 66
: 69 63 61 74 61 40 61 63 6D 65 70 65 63 2E 69 74
: }
442 30 14: SEQUENCE {
444 06 3: OBJECT IDENTIFIER keyUsage (2 5 29 15)
449 01 1: BOOLEAN TRUE
452 04 4: OCTET STRING
: 03 02 07 80
: }
458 30 31: SEQUENCE {
460 06 3: OBJECT IDENTIFIER authorityKeyIdentifier (2 5 29 35)
465 04 24: OCTET STRING
: 30 16 11 11 11 11 AA AA AA AA AA BB BB BB BB CC CC
: CC CC DD DD DD DD
: }
491 30 29: SEQUENCE {
493 06 3: OBJECT IDENTIFIER subjectKeyIdentifier (2 5 29 14)
498 04 22: OCTET STRING
: 04 14 3A FA E0 80 64 53 52 7A 3E 57 09 D8 49 A9
: 41 A8 A3 A7 0A E1
: }
: }
: }
: }
522 30 13: SEQUENCE {
524 06 9: OBJECT IDENTIFIER
: sha1withRSAEncryption (1 2 840 113549 1 1 5)
535 05 0: NULL
: }
537 03 257: BIT STRING 0 unused bits
: 87 4B 4D 25 70 A4 61 80 C9 77 0A 85 FE 79 23 CE
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: B2 2D 29 55 2F 3A F2 07 14 2B 2A BA 64 3A AA 61
: 1F F0 E7 3F C4 E6 13 E2 09 3D F0 E1 83 A0 C0 F2
: C6 71 7F 3A 1C 80 7F 15 B3 D6 1E 22 79 B8 AC 91
: 51 83 F2 3A 84 86 B6 07 2B 22 E8 01 52 2D A4 50
: 9F C6 42 D4 7C 38 B1 DD 88 CD FC E8 C3 12 C3 62
: 64 0F 16 BF 70 15 BC 01 16 78 30 2A DA FA F3 70
: E2 D3 0F 00 B0 FD 92 11 6C 55 45 48 F5 64 ED 98
: [ Another 128 bytes skipped ]
: }
5.6. PEC providers directory
The contents of the PEC providers directory MUST be queried via
[HTTP] on SSL, as described in [TLS], exclusively by licensed
providers that have the necessary user certificates; this access
modality guarantees authenticity, integrity and confidentiality
of data.
Each provider downloads the LDIF file through an [HTTPS] session,
which is authenticated by checking the X.509 certificate issued by a
certification authority.
6. PEC system client technical and functional prerequisites
This section lists the prerequisites that must be respected by a
client in order to guarantee the minimal operative functionalities
to the user of a general PEC system:
o handling of access and delivery points through secure channels;
o handling of user authentication in message dispatch and reception
which make use of standard protocols, such as [IMAP], [POP3] and
[HTTP];
o support for MIME format according to [MIME1] and [MIME5];
o support for "ISO-8859-1 (Latin-1)" character set;
o support for S/MIME v3 standard, as in [SMIMEV3], for verification
of signatures applied to PEC envelopes and notifications.
7. Security Considerations
All security considerations from [CMS] and [SMIMEV3] apply to
applications that use procedures described in this document.
The centralized LDAP server is a critical point for the security of
the whole PEC system. An attack could compromise the whole PEC
system. PEC providers that periodically download the LDIF file
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SHOULD use the best security technology to protect it from local
attacks. A PEC provider could be compromised if an attacker changed
a certificate or modified the list of domains associated
to it in the LDIF file that was copied to the PEC provider system.
When verifying the validity of the signature of a message, the
recipient system SHOULD verify that the certificate included in the
[CMS] message is present in the LDIF file (section 4.5), and that
the domain extracted by the [EMAIL] "From:" header is listed in the
managedDomains attribute associated to said certificate.
8. IANA Considerations
8.1. Registration of PEC message header fields
This document defines new header fields used in the messages that
transit in the PEC network. As specified and required by
[HEADERS-IANA], this document registers new header fields as
Provisional Message Header Fields as follows.
8.1.1. Header field: X-Riferimento-Message-ID
Applicable protocol: mail [EMAIL]
Status: provisional
Author/Change controller:
Claudio Petrucci
DigitPA
Viale Carlo Marx 31/49
00137 Roma
Italy
EMail: PETRUCCI@digitpa.gov.it
Specification document: this I-D, section 2.2.1, Appendix A.
8.1.2. Header field: X-Ricevuta
Applicable protocol: mail [EMAIL]
Status: provisional
Author/Change controller:
Claudio Petrucci
DigitPA
Viale Carlo Marx 31/49
00137 Roma
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Italy
EMail: PETRUCCI@digitpa.gov.it
Specification document: this I-D, sections 2.1.1.1.1, 3.1.2, 3.1.3,
3.1.4, 3.1.6, 3.2.1, 3.2.3, 3.2.4, 3.3.2,
3.3.3, Appendix A.
8.1.3. Header field: X-VerificaSicurezza
Applicable protocol: mail [EMAIL]
Status: provisional
Author/Change controller:
Claudio Petrucci
DigitPA
Viale Carlo Marx 31/49
00137 Roma
Italy
EMail: PETRUCCI@digitpa.gov.it
Specification document: this I-D, sections 2.1.1.1.3, 3.1.3, 3.2.4,
Appendix A.
8.1.4. Header field: X-Trasporto
Applicable protocol: mail [EMAIL]
Status: provisional
Author/Change controller:
Claudio Petrucci
DigitPA
Viale Carlo Marx 31/49
00137 Roma
Italy
EMail: PETRUCCI@digitpa.gov.it
Specification document: this I-D, sections 3.1.5, 3.2.2, Appendix A.
8.1.5. Header field: X-TipoRicevuta
Applicable protocol: mail [EMAIL]
Status: provisional
Author/Change controller:
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Claudio Petrucci
DigitPA
Viale Carlo Marx 31/49
00137 Roma
Italy
EMail: PETRUCCI@digitpa.gov.it
Specification document: this I-D, sections 3.1.5, 3.3.2, 3.3.2.1,
3.3.2.2, 3.3.2.3, Appendix A.
8.2. Registration of LDAP object identifier descriptors
This document defines new LDAP attributes and object classes for
object identifier descriptors. As specified and required by [LDAP-
IANA], this document registers new descriptors as follows per the
Expert Review.
8.2.1. Registration of Object Classes
Subject: Request for LDAP OID Registration
Descriptor (short name): See comments
Object Identifier: See comments
Person & email address to contact for further information:
See "Author/Change Controller"
Usage: object class
Specification: (I-D)
Author/Change Controller:
Claudio Petrucci
DigitPA
Viale Carlo Marx 31/49
00137 Roma
Italy
EMail: PETRUCCI@digitpa.gov.it
Comments:
The following object identifiers and associated object classes
are requested to be registered.
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OID Object Class
------------------------- -----------------------
1.3.6.1.4.1.16572.2.1.1 LDIFLocationURLObject
1.3.6.1.4.1.16572.2.1.2 provider
Please also see the associated registration request for the
providerCertificateHash, providerCertificate, providerName,
mailReceipt, managedDomains, LDIFLocationURL, and providerUnit
attribute types.
8.2.2. Registration of Attribute Types
Subject: Request for LDAP OID Registration
Descriptor (short name): See comments
Object Identifier: See comments
Person & email address to contact for further information:
See "Author/Change Controller"
Usage: attribute type
Specification: (I-D)
Author/Change Controller:
Claudio Petrucci
DigitPA
Viale Carlo Marx 31/49
00137 Roma
Italy
EMail: PETRUCCI@digitpa.gov.it
Comments:
The following object identifiers and associated attribute types
are requested to be registered.
OID Object Class
------------------------- -------------------------
1.3.6.1.4.1.16572.2.2.1 providerCertificateHash
1.3.6.1.4.1.16572.2.2.2 providerCertificate
1.3.6.1.4.1.16572.2.2.3 providerName
1.3.6.1.4.1.16572.2.2.4 mailReceipt
1.3.6.1.4.1.16572.2.2.5 managedDomains
1.3.6.1.4.1.16572.2.2.6 LDIFLocationURL
1.3.6.1.4.1.16572.2.2.7 providerUnit
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Please also see the associated registration request for the
LDIFLocationURLObject and provider object classes.
9. References
9.1. Normative References
[ABNF] Crocker, D., Editor, and P. Overell, "Augmented BNF for
Syntax Specifications: ABNF", RFC 5234, January 2008.
[CMS] Housley, R., "Cryptographic Message Syntax (CMS)", RFC
5652, Vigil Security, September 2009.
[CRL] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housely, R. and W. Polk, "Internet X.509 Public Key Infra-
structure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, May 2008.
[EMAIL] P. Resnick, Editor, "Internet Message Format", RFC 5322,
QUALCOM Incorporated, April 2001.
[] Klyne, G., Nottingham, M., and J. Mogul,
"Registration Procedures for Message Header Fields",
RFC 3864, September 2004.
[HTTP] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P. and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[HTTPS] Rescorla, E., "HTTP Over TLS", RFC 2818, RTFM, Inc.,
May 2000.
[IMAP] Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4
rev1", RFC 3501, University of Washington, March 2003.
[LDAP] K. Zeilenga, Editor, "Lightweight Directory Access
Protocol (LDAP): Technical Specification Raod Map", RFC
4510, OpenLDAP Foundation, June 2006.
[LDAP-IANA] Zeilenga, K., "Internet Assigned Numbers Authority
(IANA) Considerations for the Lightweight Direcotry
Access Protocol (LDAP)", RFC 4520, OpenLDAP
Foundation, June 2006.
[LDAP-SYNTAXES] Legg, S., Editor, "Lightweight Directory Access
Protocol (LDAP): Syntaxes and Matching Rules", RFC
4517, eB2Bcom, June 2006.
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[LDIF] Good, G., "The LDAP Data Interchange Format (LDIF) -
Technical Specification", RFC 2849, iPlanet e-commerce
Solutions, June 2000.
[MIME1] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, November 1996.
[MIME5] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part Five: Conformance Criteria and
Examples", RFC 2049, November 1996.
[SUBMISSION] Gellens, R. and J. Klensin, "Message Submission for
Mail", RFC 4409, April 2006.
[POP3] Myers, J. and M. Rose, "Post Office Protocol - Version 3",
RFC 1939, May 1996.
[REQ] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Harvard University,
March 1997.
[SHA1] Eastlake, D. and P. Jones, "US Secure Hash Algorithm 1
(SHA1)", RFC 3174, September 2001.
[MIME-SECURE] Galvin, J., Murphy, S., Crocker, S. and N. Freed,
"Security Multiparts for MIME: Multipart/Signed and
Multipart/Encrypted", RFC 1847, October 1995.
[SMIMEV3] Ramsdell, B. and S. Turner, "Secure/Multipurpose Internet
Mail Extensions (S/MIME) Version 3.2 Message
Specification", RFC 5751, January 2010.
[SMIMECERT] Ramsdell, B. and S. Turner, "Secure/Multipurpose
Internet Mail Extensions (S/MIME) Version 3.2
Certificate Handling", RFC 5750, January 2010.
[SMTP] Klensin, J. Editor, "Simple Mail Transfer Protocol", RFC
5321, AT&T Laboratories, April 2001.
[SMTP-DSN] Moore, K., "Simple Mail Transfer Protocol (SMTP)
Service Extension for Delivery Status Notifications
(DSNs)", RFC 3461, University of Tennessee, January
2003.
[SMTP-TLS] Hoffman, P., "SMTP Service Extension for Secure SMTP
over Transport Layer Security", RFC 3207, Internet
Mail Consortium, February 2002.
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[TIMESTAMP] Klyne, G. and C. Newman, "Date and Time on the
Internet: Timestamps", RFC 3339, July 2002.
[TLS] Dierks, T. and E.Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008.
10. Acknowledgments
The Italian document on which this document is based, is a product
of the collaboration of many with the supervision of the National
Center for Informatics in the Public Administration of Italy
(DigitPA).
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Appendix A: Italian fields and values in English
NOTE: The right column represents a translation of the Italian fields
for readability's sake only. Header fields that MUST be used
are the ones in the left column.
X-Riferimento-Message-ID Reference Message ID
X-Ricevuta Notification
non-accettazione non acceptance
accettazione acceptance
preavviso-errore-consegna delivery error advance notice
presa-in-carico take charge
rilevazione-virus virus detection
errore-consegna delivery error
avvenuta-consegna message delivered
X-VerificaSicurezza Security Verification
errore error
X-Trasporto Transport
posta-certificata certified mail
errore error
X-TipoRicevuta Notification Type
completa complete
breve brief
sintetica concise
certificatore certificator
Subject values:
Accettazione ACCEPTANCE
Posta certificata CERTIFIED MAIL
Presa in carico TAKE IN CHARGE
Consegna DELIVERY
Anomalia messaggio MESSAGE ANOMALY
Problema di sicurezza SECURITY PROBLEM
Avviso di non accettazione NON ACCEPTANCE PEC NOTIFICATION
Avviso di non accettazione VIRUS DETECTION INDUCED NON
per virus ACCEPTANCE PEC NOTIFICATION
Avviso di mancata consegna NON DELIVERY PEC NOTIFICATION
Avviso di mancata consegna NON DELIVERY DUE TO VIRUS PEC
per virus NOTIFICATION
Avviso di mancata consegna NON DELIVERY DUE TO TIMEOUT PEC
per sup. tempo massimo NOTIFICATION
Italian terms in the DTD relative to the certification XML file:
accettazione acceptance
altro other
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avvenuta-consegna delivered
certificato certificate
consegna delivery
data date
dati data
destinatari recipients
esterno external
errore error
errore-consegna delivery error
errore-esteso extensive error
gestore-emittente transmitting provider
giorno day
identificativo identifier
intestazione header
mittente sender
no-dest(inatario) no recipient
no-dominio no domain
non-accettazione non acceptance
nessuno none
oggetto subject
ora hour
posta-certificata certified mail
preavviso-errore-consegna delivery error advance notice
presa-in-carico take in charge
ricevuta receipt
ricezione receipt (the act of receiving)
rilevazione-virus virus detection
risposte replies
tipo type
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Appendix B: Change History
[[ This entire section is to be removed upon publication. ]]
B.1 Changes between draft-gennai-smime-cnipa-pec-03 and
draft-gennai-smime-cnipa-pec-04
Removed legal mentions in section 1.1.
Changed terminology in 2.1. System-generated messages
sender <-> author
Preceded all "transport envelope" and "notification" mentions by
"PEC" to avoid confusion with the SMTP transport envelope and DSN
notifications.
Changed section 5.1
Edited Appendix A
Updated authors' addresses
B.2 Changes between draft-gennai-smime-cnipa-pec-04 and
draft-gennai-smime-cnipa-pec-05
Added translation of Italian terms in the DTD relative to the XML
certification file.
Fixed syntax errors in the DTD.
B.3 Changes between draft-gennai-smime-cnipa-pec-05 and
draft-gennai-smime-cnipa-pec-06
Corrected use of terminology ("header field", "message body")
throughout draft.
Replaced all mentions of CNIPA with DigitaPA, except in 1.2.2 and
1.2.3.
Section 1. Introduction; added reference and link to Italian
specifications document.
Section 1.2.3 Terms and defs; edited "time stamp" definition; added
"ordinary mail" and " DigitPA" definitions; removed redundant
definitions.
Section 2.1. System-generated messages; added [MIME1] reference.
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Section 2.2.1 Access Point: reference correction (6.2 -> 5.2).
Section 2.2.2. Incoming point; added [SHA1] & [CRL] references;
removed "understand the motivations" in point: "o check what virus
typologies were not detected by its own antivirus to understand the
motivations and verify the possibility of interventions."
2.2.3 Delivery point; re-wrote non-delivery notification part.
Added section 2.2.6. Provider service email address.
Sections 3.1.2, 3.1.3, 3.1.4, 3.1.5, 3.1.6, 3.2.1, 3.2.3, 3.2.4,
3.3.2.1, 3.3.2.2, 3.3.2.3, 3.3.3 edits:
parsing the XML part only requirement, cross reference to 4.3 and
re-write (corrected use of terms "header", "attachment" and "message
body").
Section 3.3.2.2: added SHOULD requirement on hash value calculations
on base64.
Section 3.5. Example; note about possible parallelism of some steps.
Section 4.2. User date/time; added format specification in ABNF
notation.
Section 4.3.1; removed MIME type: multipart/alternative.
Section 4.5 PEC providers directory scheme; entirely re-written;
added HTTPS reference; edited urls to use "example.it" domains.
Sections 4.3. & 4.3.1; title edit.
Section 5.3 Secure interaction; added reference to [SMTP]. Removed
redundant text. Re-wrote MX record part.
Section 5.6. PEC providers directory; more details on how it
currently works.
Section 6.; references to IMAP, POP3, HTTP
Section 8. IANA Considerations: added registration request templates
for new message header fields and LDAP attributes & object classes.
Section 9. References; added ABNF, CRL, HEADERS-IANA, HTTP, HTTPS,
IMAP, LDAP-IANA, LDAP-SYNTAXES, POP3, and TIMESTAMP references;
updated all obsolete references.
Updated authors' email addresses
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B.4 Changes between draft-gennai-smime-cnipa-pec-06 and
draft-gennai-smime-cnipa-pec-07
Section 2.2.2; edited part concerning virus detection.
Section 2.2.3; re-wrote last paragraph.
Section 3.1.1; corrected use of terms; re-wrote some points to be
clearer.
Section 3.3.2.2; edited the part concerning hash substitution.
Section 4.2; fixed the note.
Section 4.3; removed restriction on charset encoding; added more
detail to describe message structure.
Section 5.2; edited the "MUST" requirement.
Section 5.3; edited the "MUST" requirement concerning MX records.
Section 5.5.1; edited clarficiation regarding Subject DN.
Appendix A; removed dashes from English column. Added note.
Replaced all occurrences of "certmail" with "postacert".
Updated authors' addresses.
Authors' Addresses
Francesco Gennai
ISTI-CNR
Via Moruzzi, 1
56126 Pisa
Italy
Email: francesco.gennai@isti.cnr.it
Alba Shahin
ISTI-CNR
Via Moruzzi, 1
56126 Pisa
Italy
Email: alba.shahin@isti.cnr.it
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Claudio Petrucci
DigitPA
Viale Marx 31/49
00137 Roma
Italy
Email: petrucci@digitpa.gov.it
Alessandro Vinciarelli
Via delle Vigne di Morena 113
00118 Roma
Italy
Email: alessandro.vinciarelli@gmail.com
Copyright Statement
Copyright (c) 2010 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with
respect to this document.
Acknowledgment
Funding for the RFC Editor function is currently provided by the
Internet Society.
Gennai et al. Expires February 05, 2011 [Page 64]
