tree-wide: remove Emacs lines from all files This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.

dhcp: make DHCP6_OPTION_* enum public libsystemd-network provides the public function sd_dhcp6_client_set_request_option() to enable the request of a given DHCP option. However the enum defining such options is defined in the internal header dhcp6-protocol.h. Move the enum definition to the public header sd-dhcp6-client.h and properly namespace values.

tree-wide: expose "p"-suffix unref calls in public APIs to make gcc cleanup easy GLIB has recently started to officially support the gcc cleanup attribute in its public API, hence let's do the same for our APIs. With this patch we'll define an xyz_unrefp() call for each public xyz_unref() call, to make it easy to use inside a __attribute__((cleanup())) expression. Then, all code is ported over to make use of this. The new calls are also documented in the man pages, with examples how to use them (well, I only added docs where the _unref() call itself already had docs, and the examples, only cover sd_bus_unrefp() and sd_event_unrefp()). This also renames sd_lldp_free() to sd_lldp_unref(), since that's how we tend to call our destructors these days. Note that this defines no public macro that wraps gcc's attribute and makes it easier to use. While I think it's our duty in the library to make our stuff easy to use, I figure it's not our duty to make gcc's own features easy to use on its own. Most likely, client code which wants to make use of this should define its own: #define _cleanup_(function) __attribute__((cleanup(function))) Or similar, to make the gcc feature easier to use. Making this logic public has the benefit that we can remove three header files whose only purpose was to define these functions internally. See #2008.

libsystemd-network: clean up recv functions

sd-dhcp6-client: bind to link-local address This ensures that several DHCPv6 clients can run on separate interfaces simultaneously.

networkd: ndisc/dhcpv6 - handle starting running clients The clients may be triggered to be started repeatedly without being stopped first, simply swallow the error rather than failing the link.

networkd: dhcp6 - don't log about losing a lease we never had

sd-dhcp6-client: add is_running() method

util-lib: split out allocation calls into alloc-util.[ch]

util-lib: move string table stuff into its own string-table.[ch]

util-lib: split out fd-related operations into fd-util.[ch] There are more than enough to deserve their own .c file, hence move them over.

sd-*.h: clean up exported (or to-be-exported) header files Exported header files should not include internal headers. Fix that. Exported header files should not use the bool type. So far we opted to stick to C89 for exported headers, and hence use "int" for bools in them. Continue to do so. Exported header files should have #include lines for everything they use including inttypes.h and sys/types.h, so that they may be included in any order. Exported header files should have C++ guards, hence add them. Exported header files should not use gcc extensions like #pragma once, get rid of it.

util-lib: split our string related calls from util.[ch] into its own file string-util.[ch] There are more than enough calls doing string manipulations to deserve its own files, hence do something about it. This patch also sorts the #include blocks of all files that needed to be updated, according to the sorting suggestions from CODING_STYLE. Since pretty much every file needs our string manipulation functions this effectively means that most files have sorted #include blocks now. Also touches a few unrelated include files.

libsystemd-network: limit accuracy of timestamps in logging We don't care about timestamps down to the last usec, round to the closest sec as that will be plenty for debugging purposes.

sd-dhcp6-client: Prevent setting and restarting of DHCPv6 client Prevent modifications to index, MAC address, DUID and Information Request while the DHCPv6 client is running. Require the DHCPv6 client to be stopped first instead of always unconditionally restarting it if the caller calls sd_dhcp6_client_start() more than once. With this change, handling of for example incoming Router Advertisments becomes much easier.

sd-dhcp6: fix namespacing Prefix all exported constants with SD_DHCP6_CLIENT_* to avoid any namespacing conflicts.

sd-dhcp6: ensure canceling lease timers and refactor setting lease Factor our common code to set/clear the client lease. Resetting the lease involves canceling old timers. Also, most importantly, when resetting the lease in client_receive_advertise(), ensure to cancel the timers too. It is not immediately clear, why at that point no timers would be pending. The lease-unref from sd_dhcp6_client_unref() can be omited, because of the preceeding client_reset() call.

dhcp: coding style fixes We place the opening bracket of a function on the same line as the function name. Let's do so in the DHCP sources too.

dhcp: stop using refcnt.h No need to invole atomic ops in single-threaded APIs, let's simplify this.

sd-dhcp: don't randomly ref objects In our API design, getter-functions don't ref objects. Calls like foo_get_bar() will not ref 'bar'. We never do that and there is no real reason to do it in single threaded APIs. If you need a ref-count, you better take it yourself *BEFORE* doing anything else on the parent object (as this might invalidate your pointer). Right now, sd_dhcp?_get_lease() refs the lease it returns. A lot of code-paths in systemd do not expect this and thus leak the lease reference. Fix this by changing the API to not ref returned objects.

sd-dhcp6: Support deprecated SNTP Configuration Option Although the SNTP option specified in RFC 4075 has been deprecated, some servers are still sending NTP information with this option. Use the SNTP information provided only if the NTP option is not present. Update the test case as SNTP information is also requested.

sd-dhcp6: Add support for DHCPv6 NTP Server Option Support NTP server and multicast addresses and NTP server domain names as specified in RFC 5908.

sd-dhcp6: Add support for DHCPv6 DNS Domain Search List option Support DHCPv6 DNS search list option as specified in RFC 3646. This option contains a list of DNS search domains encoded without compression as specified in Section 8. of RFC 3315.

sd-dhcp6: Add support for DHCPv6 DNS Recursive Name Server option Support DHCPv6 DNS server option as specified in RFC 3646. This option contains a list of IPv6 DNS server addresses.

sd-dhcp6-client: Save a DHCPv6 lease also with Information Reply As the lease structure contains interesting information, save it also for the Information Reply.

sd-dhcp6-client: Fix unreferencing DHCPv6 lease on client reset When the DHCPv6 client is started by the library user or stopped for any reason, unref the DHCPv6 lease when resetting the DHCPv6 client data structure. This makes the DHCPv6 client always start from a clean state and not keep unnecessary an lease structure around when stopped. If this is not done, a previously existing lease information can be interpreted to be from another server when restarting DHCPv6.

sd-event: make sure sd_event_now() cannot fail Previously, if the event loop never ran before sd_event_now() would fail. With this change it will instead fall back to invoking now(). This way, the function cannot fail anymore, except for programming error when invoking it with wrong parameters. This takes into account the fact that many callers did not handle the error condition correctly, and if the callers did, then they kept simply invoking now() as fall back on their own. Hence let's shorten the code using this call, and make things more robust, and let's just fall back to now() internally. Whether now() is used or the cache timestamp may still be detected via the return value of sd_event_now(). If > 0 is returned, then the fall back to now() was used, if == 0 is returned, then the cached value was returned. This patch also simplifies many of the invocations of sd_event_now(): the manual fall back to now() can be removed. Also, in cases where the call is invoked withing void functions we can now protect the invocation via assert_se(), acknowledging the fact that the call cannot fail anymore except for programming errors with the parameters. This change is inspired by #841.

dhcp6: remove unnecessary if check

sd-dhcp6-client: unref lease when freeing the client

shared: add random-util.[ch]

sd-dhcp6-client: delay setting the DUID and don't fail constructor sd_dhcp6_client_new() tried to set the DUID based on the machine id. If the host has no /etc/machine-id, the constructor would fail making it impossible to create an sd_dhcp6_client instance. Relax this and create a DUID only later as needed. This way a caller caller can workaround a missing machine-id file and set a DUID of his choosing via sd_dhcp6_client_set_duid().

network: dhcp - split out dhcp_identifier_set_{iaid,duid_en} from dhcp6-client This will also be used in dhcp4-client.

network: dhcp - split out the duid structure into a new header file We will use the same in both dhcp4 and dhcp6.

sd-dhcp6-client: Remove unnecessary debug printout

refcnt: refcnt is unsigned, fix comparisons This does not make a difference, but the code was confusing.

test-dhcp6-client: Add a simple Information Request test case Start the DHCPv6 test case by sending an Information Request, verifying the reply and continuing at once with the normal address acquisition procedure. Reuse the DHCPv6 Solicit Reply so that the client code is verified to ignore any erroneously added IPv6 address information.

sd-dhcp6-client: Implement Information Request message Implement Information Request message according to RFC 3315, section 18.1.5. with the excepion that the first message is not delayed by a random amount. Instead systemd-networkd is supposed to take care of desynchronizing between other clients. Initialize the DHCPv6 client structure in sd_dhcp6_client_start() as this allows toggling between information request and normal DHCPv6 address aquisition modes.

sd-dhcp6-client: Make end of successfull option parsing explicit When all DHCPv6 options have been parsed, dhcp6_option_parse() returns -ENOMSG. Explicitely set the return value to indicate success so that later code does not need to take this special value into account.

sd-event: rename sd_event_source_set_name() to sd_event_source_get_name() To mirror the recent name change of the concept for sd_bus objects, follow the same logic for sd_event_source objects, too.

sd-dhcp6-client: fix off-by-two error in DUID length The duid data passed by the caller does not include the DUID type, but sd_dhcp6_client_set_duid() was treating it like it did.

sd-dhcp-client: support non-Ethernet hardware addresses Like Infiniband. See RFC 4390 section 2.1 for details on DHCP and Infiniband; chaddr is zeroed, hlen is set to 0, and htype is set to ARPHRD_INFINIBAND because IB hardware addresses are 20 bytes in length.

sd-dhcp6: do basic sanity-checking of supplied DUID

sd-dhcp6: specify the type explicitly when setting custom DUID This would make it simple to verify that the data is on the right format when the type is known.

sd-dhcp6: support custom DUID's up to the size specified in the RFC

sd-dhcp6-client: support custom DUIDs The caller may have an existing DUID that it wants to use, and may want to use some other DUID generation scheme than systemd's default DUID-EN. [tomegun: whitespace - we never use tabs]

sd-dhcp6-client: Implement Elapsed Time option Implement Elapsed Time option as it is defined as MUST in RFC 3315, section 22.9. The elapsed time value is a 1/100th of a second with a max value of 0xffff, i.e. 655.35 seconds. As the main loop might not be running yet when sd_dhcp6_client_start() is called, fetch the monotonic time directly and not from the event loop while in state DHCP6_STATE_STOPPED.

sd-dhcp6-client: properly calculate buffer size when parsing options Also make pointer calculations more explicit so they are easier to understand.

sd-event: name event sources used in libraries This should help in debugging failing event sources.

indentation/spurious whitespace fixes

libsystemd-network: use CLOCK_BOOTTIME instead of CLOCK_MONOTONIC where possible The timeouts in the networking library (DHCP lease timeouts and similar) should not be affected by suspend. In the cases where CLOCK_BOOTTIME is not implemented, it is still safe to fallback to CLOCK_MONOTONIC, as the consumers of the library (i.e., networkd) _should_ renew the leases when coming out of suspend.

dhcp-network: remove unused DHCP6_STATE_RS Probably a left-over from when router solicitations were requested in the DHCP6 code. But since they are now separate, this state is no longer needed.

sd-dhcp6-client: make gcc happy It complains about {max,init}_retransmit_time possibly being uninitialized. It is wrong, but let's just initialize it.

networkd: don't clear dhcpv6 lease timers if there's no previous lease If client->lease is NULL, dhcp6_lease_clear_timers will cause a segmentation fault.

sd-dhcp6-client: initialize variable

sd-dhcp6-client: check return value Checking the return values seems to have been forgotten in ed6ee21953dac9c78383da00bc4514ece6b75ab5

sd-dhcp6-client: fix free before use

sd-dhcp6-client: Implement Rapid Commit Add a Rapid Commit option to Solicit messages and expect a Reply to be received instead of an Advertise. When receiving a DHCPv6 message from the server in state Solicit, continue testing whether the message is a Reply. Ease up the message type checking, it's not fatal if the message is of a wrong type. Add helper functions to set/get the rapid commit of a lease. See RFC 3315, sections 17., 17.1.2., 17.1.4. and 18.1.8.

sd-dhcp6-client: Implement Renew and Rebind Start sending Renew and Rebind DHCPv6 messages when respective timers T1 and T2 expire. Rebind messages do not include a Server ID option and the Rebind procedure ends when the last IPv6 address valid lifetime expires, whereafter the client restarts the address acquisition procedure by Soliciting for available servers. See RFC 3315, sections 18.1.3. and 18.1.4. for details.

sd-dhcp6-client: Add Option Request Option support Provide a function to request more options from the DHCPv6 server. Provide a sensible default set at startup and add test basic test cases for the intended usage. Define DNS and NTP related option codes and add comments for the unassigned codes.

sd-dhcp6-client: return NULL from _unref() like the other sd-* libraries In order to keep the refcounting working, a DONT_DESTROY macro similar to the one in sd-bus has been added also to DHCPv6.

sd-dhcp6-client: use %m instead of strerror(errno)

sd-dhcp6-client: fix uninitialized variables

sd-dhcp6-client: Initialize fd to -1 and rename function client_initialize name is misleading, since the function is actually useful at the *end*, to reinitialize the object. But reset is shorter, so rename it to client_reset.

sd-dhcp6-client: Receive and parse a reply and set T1 and T2 timers Receive and parse a Reply from the server. Set up T1 and T2 timers and notify the library user of an acquired DHCPv6 lease.

sd-dhcp6-client: Add Request message sending As described in RFC 3315, Section 17.1.2, a client has to wait until the first timeout has elapsed before it is allowed to request IPv6 addresses from the DHCPv6 server. This is indicated by a non-NULL lease and a non-zero resend count. Should the Advertisement contain a preference value of 255 or be received after the first timeout, IPv6 address requesting is started immediately. In response to these events, create a Request message and set up proper resend timers to send the message to the server.

sd-dhcp6-client: Update start function to take a state Update the start function so that the client state can be conveniently changed with the previous message resend timers cleared. On initial startup also create and bind to the UDP socket.

sd-dhcp6-lease: Add functions for accessing lease and addresses Add support functions for accessing the current client lease as well as iterating over the addresses and get their preferred and valid lifetimes.

sd-dhcp6-client: Receive and parse Advertise messages When receiving DHCPv6 messages, discard the ones that are not meant for DHCPv6 clients and verify the transaction id. Once that is done, process the Advertise message and select the Advertise with the highest preference. Create a separate function for lease information parsing so that it can be reused in other parts of the protocol. Verify both DUID and IAID in the received message and store other necessary information with the lease structure.

sd-dhcp6-client: Add DHCPv6 Solicit message creation and sending Implement the initial functionality used for creating a DHCPv6 Solicit message containing the needed options and send it to the DHCPv6 broadcast address. Increase the sent message count and ensure that the Solicit Initial Retransmission Time is strictly greater than the Solicitation IRT as described in RFC 3315, section 17.1.2.

sd-dhcp6-client: Add DHCPv6 client Solicitation timeout handling Add the core of DHCPv6 client message retransmission and upper bound timer and message count handling according to RFC 3315 Secions 7.1.2 and 14. Omit the DHCPv6 initial delay; for now it is assumed that systemd-networkd will provide decent startup randomization that will desynchronize the clients. When reinitializing the client, clear all timers.

sd-dhcp6-client: Add DHCPv6 IAID functionality Create structures describing Identity Association IDentifiers and IPv6 lease addresses. [tomegun: initialize the IAID when client is started. Base this off of the predictable udev names, if available, as these satisfy the requirement of the IAID, and base it off the mac addres otherwise, as that is the best we have.]

sd-dhcp6-client: Initialize DUID Initialize DHCP Unique Identifier when creating the client. The DUID is generated based on the machine-id, which satisfies all the requirements of what an DUID should be. The DUID type is DUID-EN. Based on patch by Patrik Flykt.

sd-dhcp6-client: Add initial DHCPv6 client files Add initial structure definition and functions for setting index, MAC address, callback and event loop. Define protocol values and states.