diff options
author | Tom Gundersen <teg@jklm.no> | 2014-01-05 23:01:10 +0100 |
---|---|---|
committer | Tom Gundersen <teg@jklm.no> | 2014-01-12 15:37:21 +0100 |
commit | 3bef724f7e7f7eaca69881548b06e221b77d7031 (patch) | |
tree | 0b17e5a43d7e5c5d07dc696d23d4c829f9ab7200 | |
parent | 924fe4304af981ffd849346b4a1d415f11e9dd79 (diff) |
networkd: generate resolv.conf
This adds support to generate a basic resolv.conf in /run/systemd/network.
This file will not take any effect unless a symlink is created from
/etc/resolv.conf.
Nameservers received over DHCP takes precedence over statically configured ones.
Note: /etc/resolv.conf is severely limited, so in the future we will likely
rather provide a much more powerfull nss plugin (or something to that effect),
but this should allow current users to function without any loss of
functionality.
-rw-r--r-- | Makefile.am | 2 | ||||
-rw-r--r-- | src/network/networkd-address.c | 37 | ||||
-rw-r--r-- | src/network/networkd-gperf.gperf | 1 | ||||
-rw-r--r-- | src/network/networkd-link.c | 8 | ||||
-rw-r--r-- | src/network/networkd-manager.c | 75 | ||||
-rw-r--r-- | src/network/networkd-network.c | 8 | ||||
-rw-r--r-- | src/network/networkd.c | 7 | ||||
-rw-r--r-- | src/network/networkd.h | 8 |
8 files changed, 146 insertions, 0 deletions
diff --git a/Makefile.am b/Makefile.am index 65b445ec5..b4bb6e1e3 100644 --- a/Makefile.am +++ b/Makefile.am @@ -4104,12 +4104,13 @@ systemd_networkd_LDADD = \ libudev-internal.la \ libsystemd-daemon-internal.la \ libsystemd-bus-internal.la \ libsystemd-id128-internal.la \ libsystemd-rtnl.la \ libsystemd-dhcp.la \ + libsystemd-label.la \ libsystemd-shared.la nodist_systemunit_DATA += \ units/systemd-networkd.service MULTI_USER_TARGET_WANTS += \ @@ -4130,12 +4131,13 @@ test_network_LDADD = \ libudev-internal.la \ libsystemd-bus-internal.la \ libsystemd-id128-internal.la \ libsystemd-daemon-internal.la \ libsystemd-rtnl.la \ libsystemd-dhcp.la \ + libsystemd-label.la \ libsystemd-shared.la tests += \ test-network EXTRA_DIST += \ diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c index 8a7163005..7d06cf887 100644 --- a/src/network/networkd-address.c +++ b/src/network/networkd-address.c @@ -187,12 +187,49 @@ int address_configure(Address *address, Link *link, return r; } return 0; } +int config_parse_dns(const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + Address **dns = data; + _cleanup_address_free_ Address *n = NULL; + int r; + + assert(filename); + assert(section); + assert(lvalue); + assert(rvalue); + assert(data); + + r = address_new_dynamic(&n); + if (r < 0) + return r; + + r = net_parse_inaddr(rvalue, &n->family, &n->in_addr); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, EINVAL, + "DNS address is invalid, ignoring assignment: %s", rvalue); + return 0; + } + + *dns = n; + n = NULL; + + return 0; +} + int config_parse_address(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, diff --git a/src/network/networkd-gperf.gperf b/src/network/networkd-gperf.gperf index f1594d56c..92954a836 100644 --- a/src/network/networkd-gperf.gperf +++ b/src/network/networkd-gperf.gperf @@ -22,12 +22,13 @@ Match.Type, config_parse_string, 0, offsetof(Networ Match.Name, config_parse_ifname, 0, offsetof(Network, match_name) Network.Description, config_parse_string, 0, offsetof(Network, description) Network.Bridge, config_parse_bridge, 0, offsetof(Network, bridge) Network.DHCP, config_parse_bool, 0, offsetof(Network, dhcp) Network.Address, config_parse_address, 0, 0 Network.Gateway, config_parse_gateway, 0, 0 +Network.DNS, config_parse_dns, 0, offsetof(Network, dns) Address.Address, config_parse_address, 0, 0 Address.Label, config_parse_label, 0, 0 Route.Gateway, config_parse_gateway, 0, 0 Route.Destination, config_parse_destination, 0, 0 Bridge.Description, config_parse_string, 0, offsetof(Bridge, description) Bridge.Name, config_parse_ifname, 0, offsetof(Bridge, name) diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c index 25d92c8aa..5dd8e9100 100644 --- a/src/network/networkd-link.c +++ b/src/network/networkd-link.c @@ -375,12 +375,13 @@ static void dhcp_handler(sd_dhcp_client *client, int event, void *userdata) { return; } if (event == DHCP_EVENT_IP_CHANGE || event == DHCP_EVENT_IP_ACQUIRE) { _cleanup_address_free_ Address *addr = NULL; _cleanup_route_free_ Route *rt = NULL; + struct in_addr **nameservers; log_struct_link(LOG_INFO, link, "MESSAGE=%s: DHCPv4 address %u.%u.%u.%u/%u via %u.%u.%u.%u", link->ifname, ADDRESS_FMT_VAL(address), prefixlen, @@ -417,12 +418,19 @@ static void dhcp_handler(sd_dhcp_client *client, int event, void *userdata) { link->dhcp_address = addr; link->dhcp_route = rt; addr = NULL; rt = NULL; + r = sd_dhcp_client_get_dns(client, &nameservers); + if (r >= 0) { + r = manager_update_resolv_conf(link->manager); + if (r < 0) + log_error("Failed to update resolv.conf"); + } + link_enter_set_addresses(link); } return; } diff --git a/src/network/networkd-manager.c b/src/network/networkd-manager.c index c9ce1d6a1..f02eed1a5 100644 --- a/src/network/networkd-manager.c +++ b/src/network/networkd-manager.c @@ -16,16 +16,19 @@ Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ +#include <resolv.h> + #include "path-util.h" #include "networkd.h" #include "libudev-private.h" #include "udev-util.h" +#include "mkdir.h" const char* const network_dirs[] = { "/etc/systemd/network", "/run/systemd/network", "/usr/lib/systemd/network", #ifdef HAVE_SPLIT_USER @@ -273,6 +276,78 @@ int manager_rtnl_listen(Manager *m) { r = sd_rtnl_add_match(m->rtnl, RTM_NEWLINK, &manager_rtnl_process_link, m); if (r < 0) return r; return 0; } + +static void append_dns(FILE *f, struct in_addr *dns, unsigned char family, unsigned *count) { + char buf[INET6_ADDRSTRLEN]; + const char *address; + + address = inet_ntop(family, dns, buf, INET6_ADDRSTRLEN); + if (!address) { + log_warning("Invalid DNS address. Ignoring."); + return; + } + + if (*count == MAXNS) + fputs("# Too many dynamic name servers configured, the " + "following entries will be ignored\n", f); + + fprintf(f, "nameserver %s\n", address); + + (*count) ++; +} + +int manager_update_resolv_conf(Manager *m) { + _cleanup_free_ char *temp_path = NULL; + _cleanup_fclose_ FILE *f = NULL; + Link *link; + Iterator i; + unsigned count = 0; + int r; + + assert(m); + + r = mkdir_safe_label("/run/systemd/network", 0755, 0, 0); + if (r < 0) + return r; + + r = fopen_temporary("/run/systemd/network/resolv.conf", &f, &temp_path); + if (r < 0) + return r; + + fchmod(fileno(f), 0644); + + fputs("# This file is managed by systemd-networkd(8). Do not edit.\n", f); + + HASHMAP_FOREACH(link, m->links, i) { + if (link->dhcp) { + struct in_addr **nameservers; + + r = sd_dhcp_client_get_dns(link->dhcp, &nameservers); + if (r >= 0) { + unsigned j; + + for (j = 0; nameservers[j]; j++) + append_dns(f, nameservers[j], AF_INET, &count); + } + } + } + + HASHMAP_FOREACH(link, m->links, i) + if (link->network && link->network->dns) + append_dns(f, &link->network->dns->in_addr.in, + link->network->dns->family, &count); + + fflush(f); + + if (ferror(f) || rename(temp_path, "/run/systemd/network/resolv.conf") < 0) { + r = -errno; + unlink("/run/systemd/network/resolv.conf"); + unlink(temp_path); + return r; + } + + return 0; +} diff --git a/src/network/networkd-network.c b/src/network/networkd-network.c index f2546440c..f98731001 100644 --- a/src/network/networkd-network.c +++ b/src/network/networkd-network.c @@ -141,12 +141,14 @@ void network_free(Network *network) { free(network->match_driver); free(network->match_type); free(network->match_name); free(network->description); + address_free(network->dns); + while ((route = network->static_routes)) route_free(route); while ((address = network->static_addresses)) address_free(address); @@ -194,12 +196,18 @@ int network_apply(Manager *manager, Network *network, Link *link) { link->network = network; r = link_configure(link); if (r < 0) return r; + if (network->dns) { + r = manager_update_resolv_conf(manager); + if (r < 0) + return r; + } + return 0; } int config_parse_bridge(const char *unit, const char *filename, unsigned line, diff --git a/src/network/networkd.c b/src/network/networkd.c index 360afba98..055200cb0 100644 --- a/src/network/networkd.c +++ b/src/network/networkd.c @@ -57,12 +57,19 @@ int main(int argc, char *argv[]) { goto out; r = manager_rtnl_listen(m); if (r < 0) goto out; + + /* write out empty resolv.conf to avoid a + * dangling symlink */ + r = manager_update_resolv_conf(m); + if (r < 0) + goto out; + sd_notify(false, "READY=1\n" "STATUS=Processing requests..."); r = sd_event_loop(m->event); if (r < 0) diff --git a/src/network/networkd.h b/src/network/networkd.h index 55181f2bb..607feba0e 100644 --- a/src/network/networkd.h +++ b/src/network/networkd.h @@ -85,12 +85,13 @@ struct Network { char *description; Bridge *bridge; bool dhcp; LIST_HEAD(Address, static_addresses); LIST_HEAD(Route, static_routes); + Address *dns; Hashmap *addresses_by_section; Hashmap *routes_by_section; LIST_FIELDS(Network, networks); }; @@ -154,12 +155,13 @@ struct Link { unsigned flags; Network *network; Route *dhcp_route; Address *dhcp_address; + Address *dns; LinkState state; unsigned addr_messages; unsigned route_messages; @@ -192,12 +194,14 @@ bool manager_should_reload(Manager *m); int manager_udev_enumerate_links(Manager *m); int manager_udev_listen(Manager *m); int manager_rtnl_listen(Manager *m); +int manager_update_resolv_conf(Manager *m); + DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_free); #define _cleanup_manager_free_ _cleanup_(manager_freep) /* Bridge */ int bridge_load(Manager *manager); @@ -255,12 +259,16 @@ void address_free(Address *address); int address_configure(Address *address, Link *link, sd_rtnl_message_handler_t callback); int address_drop(Address *address, Link *link, sd_rtnl_message_handler_t callback); DEFINE_TRIVIAL_CLEANUP_FUNC(Address*, address_free); #define _cleanup_address_free_ _cleanup_(address_freep) +int config_parse_dns(const char *unit, const char *filename, unsigned line, + const char *section, unsigned section_line, const char *lvalue, + int ltype, const char *rvalue, void *data, void *userdata); + int config_parse_address(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); int config_parse_label(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, |