diff options
Diffstat (limited to 'src/libsystemd-network/sd-icmp6-nd.c')
| -rw-r--r-- | src/libsystemd-network/sd-icmp6-nd.c | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/src/libsystemd-network/sd-icmp6-nd.c b/src/libsystemd-network/sd-icmp6-nd.c new file mode 100644 index 0000000000..f820a9c8f0 --- /dev/null +++ b/src/libsystemd-network/sd-icmp6-nd.c @@ -0,0 +1,325 @@ +/*** + This file is part of systemd. + + Copyright (C) 2014 Intel Corporation. All rights reserved. + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + 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 <netinet/icmp6.h> +#include <string.h> +#include <stdbool.h> +#include <netinet/in.h> + +#include "socket-util.h" +#include "refcnt.h" +#include "async.h" + +#include "dhcp6-internal.h" +#include "sd-icmp6-nd.h" + +#define ICMP6_ROUTER_SOLICITATION_INTERVAL 4 * USEC_PER_SEC +#define ICMP6_MAX_ROUTER_SOLICITATIONS 3 + +enum icmp6_nd_state { + ICMP6_NEIGHBOR_DISCOVERY_IDLE = 0, + ICMP6_ROUTER_SOLICITATION_SENT = 10, + ICMP6_ROUTER_ADVERTISMENT_LISTEN = 11, +}; + +struct sd_icmp6_nd { + RefCount n_ref; + + enum icmp6_nd_state state; + sd_event *event; + int event_priority; + int index; + struct ether_addr mac_addr; + int fd; + sd_event_source *recv; + sd_event_source *timeout; + int nd_sent; + sd_icmp6_nd_callback_t callback; + void *userdata; +}; + +#define log_icmp6_nd(p, fmt, ...) log_meta(LOG_DEBUG, __FILE__, __LINE__, __func__, "ICMPv6 CLIENT: " fmt, ##__VA_ARGS__) + +static void icmp6_nd_notify(sd_icmp6_nd *nd, int event) +{ + if (nd->callback) + nd->callback(nd, event, nd->userdata); +} + +int sd_icmp6_nd_set_callback(sd_icmp6_nd *nd, sd_icmp6_nd_callback_t callback, + void *userdata) { + assert(nd); + + nd->callback = callback; + nd->userdata = userdata; + + return 0; +} + +int sd_icmp6_nd_set_index(sd_icmp6_nd *nd, int interface_index) { + assert(nd); + assert(interface_index >= -1); + + nd->index = interface_index; + + return 0; +} + +int sd_icmp6_nd_set_mac(sd_icmp6_nd *nd, const struct ether_addr *mac_addr) { + assert(nd); + + if (mac_addr) + memcpy(&nd->mac_addr, mac_addr, sizeof(nd->mac_addr)); + else + memset(&nd->mac_addr, 0x00, sizeof(nd->mac_addr)); + + return 0; + +} + +int sd_icmp6_nd_attach_event(sd_icmp6_nd *nd, sd_event *event, int priority) { + int r; + + assert_return(nd, -EINVAL); + assert_return(!nd->event, -EBUSY); + + if (event) + nd->event = sd_event_ref(event); + else { + r = sd_event_default(&nd->event); + if (r < 0) + return 0; + } + + nd->event_priority = priority; + + return 0; +} + +int sd_icmp6_nd_detach_event(sd_icmp6_nd *nd) { + assert_return(nd, -EINVAL); + + nd->event = sd_event_unref(nd->event); + + return 0; +} + +sd_event *sd_icmp6_nd_get_event(sd_icmp6_nd *nd) { + assert(nd); + + return nd->event; +} + +sd_icmp6_nd *sd_icmp6_nd_ref(sd_icmp6_nd *nd) { + assert (nd); + + assert_se(REFCNT_INC(nd->n_ref) >= 2); + + return nd; +} + +static int icmp6_nd_init(sd_icmp6_nd *nd) { + assert(nd); + + nd->recv = sd_event_source_unref(nd->recv); + nd->fd = asynchronous_close(nd->fd); + nd->timeout = sd_event_source_unref(nd->timeout); + + return 0; +} + +sd_icmp6_nd *sd_icmp6_nd_unref(sd_icmp6_nd *nd) { + if (nd && REFCNT_DEC(nd->n_ref) <= 0) { + + icmp6_nd_init(nd); + sd_icmp6_nd_detach_event(nd); + + free(nd); + } + + return NULL; +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(sd_icmp6_nd*, sd_icmp6_nd_unref); +#define _cleanup_sd_icmp6_nd_free_ _cleanup_(sd_icmp6_nd_unrefp) + +int sd_icmp6_nd_new(sd_icmp6_nd **ret) { + _cleanup_sd_icmp6_nd_free_ sd_icmp6_nd *nd = NULL; + + assert(ret); + + nd = new0(sd_icmp6_nd, 1); + if (!nd) + return -ENOMEM; + + nd->n_ref = REFCNT_INIT; + + nd->index = -1; + + *ret = nd; + nd = NULL; + + return 0; +} + +static int icmp6_router_advertisment_recv(sd_event_source *s, int fd, + uint32_t revents, void *userdata) +{ + sd_icmp6_nd *nd = userdata; + ssize_t len; + struct nd_router_advert ra; + int event = ICMP6_EVENT_ROUTER_ADVERTISMENT_NONE; + + assert(s); + assert(nd); + assert(nd->event); + + /* only interested in Managed/Other flag */ + len = read(fd, &ra, sizeof(ra)); + if ((size_t)len < sizeof(ra)) + return 0; + + if (ra.nd_ra_type != ND_ROUTER_ADVERT) + return 0; + + if (ra.nd_ra_code != 0) + return 0; + + nd->timeout = sd_event_source_unref(nd->timeout); + + nd->state = ICMP6_ROUTER_ADVERTISMENT_LISTEN; + + if (ra.nd_ra_flags_reserved & ND_RA_FLAG_OTHER ) + event = ICMP6_EVENT_ROUTER_ADVERTISMENT_OTHER; + + if (ra.nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) + event = ICMP6_EVENT_ROUTER_ADVERTISMENT_MANAGED; + + log_icmp6_nd(nd, "Received Router Advertisment flags %s/%s", + (ra.nd_ra_flags_reserved & ND_RA_FLAG_MANAGED)? "MANAGED": + "none", + (ra.nd_ra_flags_reserved & ND_RA_FLAG_OTHER)? "OTHER": + "none"); + + icmp6_nd_notify(nd, event); + + return 0; +} + +static int icmp6_router_solicitation_timeout(sd_event_source *s, uint64_t usec, + void *userdata) +{ + sd_icmp6_nd *nd = userdata; + uint64_t time_now, next_timeout; + struct ether_addr unset = { }; + struct ether_addr *addr = NULL; + int r; + + assert(s); + assert(nd); + assert(nd->event); + + nd->timeout = sd_event_source_unref(nd->timeout); + + if (nd->nd_sent >= ICMP6_MAX_ROUTER_SOLICITATIONS) { + icmp6_nd_notify(nd, ICMP6_EVENT_ROUTER_ADVERTISMENT_TIMEOUT); + nd->state = ICMP6_ROUTER_ADVERTISMENT_LISTEN; + } else { + if (memcmp(&nd->mac_addr, &unset, sizeof(struct ether_addr))) + addr = &nd->mac_addr; + + r = dhcp_network_icmp6_send_router_solicitation(nd->fd, addr); + if (r < 0) + log_icmp6_nd(nd, "Error sending Router Solicitation"); + else { + nd->state = ICMP6_ROUTER_SOLICITATION_SENT; + log_icmp6_nd(nd, "Sent Router Solicitation"); + } + + nd->nd_sent++; + + r = sd_event_now(nd->event, CLOCK_MONOTONIC, &time_now); + if (r < 0) { + icmp6_nd_notify(nd, r); + return 0; + } + + next_timeout = time_now + ICMP6_ROUTER_SOLICITATION_INTERVAL; + + r = sd_event_add_time(nd->event, &nd->timeout, CLOCK_MONOTONIC, + next_timeout, 0, + icmp6_router_solicitation_timeout, nd); + if (r < 0) { + icmp6_nd_notify(nd, r); + return 0; + } + + r = sd_event_source_set_priority(nd->timeout, + nd->event_priority); + if (r < 0) { + icmp6_nd_notify(nd, r); + return 0; + } + } + + return 0; +} + +int sd_icmp6_router_solicitation_start(sd_icmp6_nd *nd) { + int r; + + assert(nd); + assert(nd->event); + + if (nd->state != ICMP6_NEIGHBOR_DISCOVERY_IDLE) + return -EINVAL; + + if (nd->index < 1) + return -EINVAL; + + r = dhcp_network_icmp6_bind_router_solicitation(nd->index); + if (r < 0) + return r; + + nd->fd = r; + + r = sd_event_add_io(nd->event, &nd->recv, nd->fd, EPOLLIN, + icmp6_router_advertisment_recv, nd); + if (r < 0) + goto error; + + r = sd_event_source_set_priority(nd->recv, nd->event_priority); + if (r < 0) + goto error; + + r = sd_event_add_time(nd->event, &nd->timeout, CLOCK_MONOTONIC, + 0, 0, icmp6_router_solicitation_timeout, nd); + if (r < 0) + goto error; + + r = sd_event_source_set_priority(nd->timeout, nd->event_priority); + +error: + if (r < 0) + icmp6_nd_init(nd); + else + log_icmp6_nd(client, "Start Router Solicitation"); + + return r; +} |