diff options
Diffstat (limited to 'src/network/netdev/wireguard.c')
| -rw-r--r-- | src/network/netdev/wireguard.c | 946 |
1 files changed, 946 insertions, 0 deletions
diff --git a/src/network/netdev/wireguard.c b/src/network/netdev/wireguard.c new file mode 100644 index 0000000..416e9b9 --- /dev/null +++ b/src/network/netdev/wireguard.c @@ -0,0 +1,946 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/*** + Copyright © 2015-2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. +***/ + +#include <sys/ioctl.h> +#include <net/if.h> + +#include "sd-resolve.h" + +#include "alloc-util.h" +#include "event-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "hexdecoct.h" +#include "memory-util.h" +#include "netlink-util.h" +#include "networkd-manager.h" +#include "networkd-util.h" +#include "parse-util.h" +#include "path-util.h" +#include "resolve-private.h" +#include "string-util.h" +#include "strv.h" +#include "wireguard.h" + +static void resolve_endpoints(NetDev *netdev); + +static void wireguard_peer_free(WireguardPeer *peer) { + WireguardIPmask *mask; + + if (!peer) + return; + + if (peer->wireguard) { + LIST_REMOVE(peers, peer->wireguard->peers, peer); + + set_remove(peer->wireguard->peers_with_unresolved_endpoint, peer); + set_remove(peer->wireguard->peers_with_failed_endpoint, peer); + + if (peer->section) + hashmap_remove(peer->wireguard->peers_by_section, peer->section); + } + + network_config_section_free(peer->section); + + while ((mask = peer->ipmasks)) { + LIST_REMOVE(ipmasks, peer->ipmasks, mask); + free(mask); + } + + free(peer->endpoint_host); + free(peer->endpoint_port); + free(peer->preshared_key_file); + explicit_bzero_safe(peer->preshared_key, WG_KEY_LEN); + + free(peer); +} + +DEFINE_NETWORK_SECTION_FUNCTIONS(WireguardPeer, wireguard_peer_free); + +static int wireguard_peer_new_static(Wireguard *w, const char *filename, unsigned section_line, WireguardPeer **ret) { + _cleanup_(network_config_section_freep) NetworkConfigSection *n = NULL; + _cleanup_(wireguard_peer_freep) WireguardPeer *peer = NULL; + int r; + + assert(w); + assert(ret); + assert(filename); + assert(section_line > 0); + + r = network_config_section_new(filename, section_line, &n); + if (r < 0) + return r; + + peer = hashmap_get(w->peers_by_section, n); + if (peer) { + *ret = TAKE_PTR(peer); + return 0; + } + + peer = new(WireguardPeer, 1); + if (!peer) + return -ENOMEM; + + *peer = (WireguardPeer) { + .flags = WGPEER_F_REPLACE_ALLOWEDIPS, + .wireguard = w, + .section = TAKE_PTR(n), + }; + + LIST_PREPEND(peers, w->peers, peer); + + r = hashmap_ensure_allocated(&w->peers_by_section, &network_config_hash_ops); + if (r < 0) + return r; + + r = hashmap_put(w->peers_by_section, peer->section, peer); + if (r < 0) + return r; + + *ret = TAKE_PTR(peer); + return 0; +} + +static int wireguard_set_ipmask_one(NetDev *netdev, sd_netlink_message *message, const WireguardIPmask *mask, uint16_t index) { + int r; + + assert(message); + assert(mask); + assert(index > 0); + + /* This returns 1 on success, 0 on recoverable error, and negative errno on failure. */ + + r = sd_netlink_message_open_array(message, index); + if (r < 0) + return 0; + + r = sd_netlink_message_append_u16(message, WGALLOWEDIP_A_FAMILY, mask->family); + if (r < 0) + goto cancel; + + r = netlink_message_append_in_addr_union(message, WGALLOWEDIP_A_IPADDR, mask->family, &mask->ip); + if (r < 0) + goto cancel; + + r = sd_netlink_message_append_u8(message, WGALLOWEDIP_A_CIDR_MASK, mask->cidr); + if (r < 0) + goto cancel; + + r = sd_netlink_message_close_container(message); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not add wireguard allowed ip: %m"); + + return 1; + +cancel: + r = sd_netlink_message_cancel_array(message); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not cancel wireguard allowed ip message attribute: %m"); + + return 0; +} + +static int wireguard_set_peer_one(NetDev *netdev, sd_netlink_message *message, const WireguardPeer *peer, uint16_t index, WireguardIPmask **mask_start) { + WireguardIPmask *mask, *start; + uint16_t j = 0; + int r; + + assert(message); + assert(peer); + assert(index > 0); + assert(mask_start); + + /* This returns 1 on success, 0 on recoverable error, and negative errno on failure. */ + + start = *mask_start ?: peer->ipmasks; + + r = sd_netlink_message_open_array(message, index); + if (r < 0) + return 0; + + r = sd_netlink_message_append_data(message, WGPEER_A_PUBLIC_KEY, &peer->public_key, sizeof(peer->public_key)); + if (r < 0) + goto cancel; + + if (!*mask_start) { + r = sd_netlink_message_append_data(message, WGPEER_A_PRESHARED_KEY, &peer->preshared_key, WG_KEY_LEN); + if (r < 0) + goto cancel; + + r = sd_netlink_message_append_u32(message, WGPEER_A_FLAGS, peer->flags); + if (r < 0) + goto cancel; + + r = sd_netlink_message_append_u16(message, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL, peer->persistent_keepalive_interval); + if (r < 0) + goto cancel; + + if (IN_SET(peer->endpoint.sa.sa_family, AF_INET, AF_INET6)) { + r = netlink_message_append_sockaddr_union(message, WGPEER_A_ENDPOINT, &peer->endpoint); + if (r < 0) + goto cancel; + } + } + + r = sd_netlink_message_open_container(message, WGPEER_A_ALLOWEDIPS); + if (r < 0) + goto cancel; + + LIST_FOREACH(ipmasks, mask, start) { + r = wireguard_set_ipmask_one(netdev, message, mask, ++j); + if (r < 0) + return r; + if (r == 0) + break; + } + + r = sd_netlink_message_close_container(message); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not add wireguard allowed ip: %m"); + + r = sd_netlink_message_close_container(message); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not add wireguard peer: %m"); + + *mask_start = mask; /* Start next cycle from this mask. */ + return !mask; + +cancel: + r = sd_netlink_message_cancel_array(message); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not cancel wireguard peers: %m"); + + return 0; +} + +static int wireguard_set_interface(NetDev *netdev) { + _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL; + WireguardIPmask *mask_start = NULL; + WireguardPeer *peer, *peer_start; + bool sent_once = false; + uint32_t serial; + Wireguard *w; + int r; + + assert(netdev); + w = WIREGUARD(netdev); + assert(w); + + for (peer_start = w->peers; peer_start || !sent_once; ) { + uint16_t i = 0; + + message = sd_netlink_message_unref(message); + + r = sd_genl_message_new(netdev->manager->genl, SD_GENL_WIREGUARD, WG_CMD_SET_DEVICE, &message); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Failed to allocate generic netlink message: %m"); + + r = sd_netlink_message_append_string(message, WGDEVICE_A_IFNAME, netdev->ifname); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not append wireguard interface name: %m"); + + if (peer_start == w->peers) { + r = sd_netlink_message_append_data(message, WGDEVICE_A_PRIVATE_KEY, &w->private_key, WG_KEY_LEN); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not append wireguard private key: %m"); + + r = sd_netlink_message_append_u16(message, WGDEVICE_A_LISTEN_PORT, w->port); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not append wireguard port: %m"); + + r = sd_netlink_message_append_u32(message, WGDEVICE_A_FWMARK, w->fwmark); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not append wireguard fwmark: %m"); + + r = sd_netlink_message_append_u32(message, WGDEVICE_A_FLAGS, w->flags); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not append wireguard flags: %m"); + } + + r = sd_netlink_message_open_container(message, WGDEVICE_A_PEERS); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not append wireguard peer attributes: %m"); + + LIST_FOREACH(peers, peer, peer_start) { + r = wireguard_set_peer_one(netdev, message, peer, ++i, &mask_start); + if (r < 0) + return r; + if (r == 0) + break; + } + peer_start = peer; /* Start next cycle from this peer. */ + + r = sd_netlink_message_close_container(message); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not close wireguard container: %m"); + + r = sd_netlink_send(netdev->manager->genl, message, &serial); + if (r < 0) + return log_netdev_error_errno(netdev, r, "Could not set wireguard device: %m"); + + sent_once = true; + } + + return 0; +} + +static void wireguard_peer_destroy_callback(WireguardPeer *peer) { + NetDev *netdev; + + assert(peer); + assert(peer->wireguard); + + netdev = NETDEV(peer->wireguard); + + if (section_is_invalid(peer->section)) + wireguard_peer_free(peer); + + netdev_unref(netdev); +} + +static int on_resolve_retry(sd_event_source *s, usec_t usec, void *userdata) { + NetDev *netdev = userdata; + Wireguard *w; + + assert(netdev); + w = WIREGUARD(netdev); + assert(w); + + if (!netdev_is_managed(netdev)) + return 0; + + assert(set_isempty(w->peers_with_unresolved_endpoint)); + + SWAP_TWO(w->peers_with_unresolved_endpoint, w->peers_with_failed_endpoint); + + resolve_endpoints(netdev); + + return 0; +} + +/* + * Given the number of retries this function will return will an exponential + * increasing time in milliseconds to wait starting at 200ms and capped at 25 seconds. + */ +static int exponential_backoff_milliseconds(unsigned n_retries) { + return (2 << MIN(n_retries, 7U)) * 100 * USEC_PER_MSEC; +} + +static int wireguard_resolve_handler(sd_resolve_query *q, + int ret, + const struct addrinfo *ai, + WireguardPeer *peer) { + NetDev *netdev; + Wireguard *w; + int r; + + assert(peer); + assert(peer->wireguard); + + w = peer->wireguard; + netdev = NETDEV(w); + + if (!netdev_is_managed(netdev)) + return 0; + + if (ret != 0) { + log_netdev_error(netdev, "Failed to resolve host '%s:%s': %s", peer->endpoint_host, peer->endpoint_port, gai_strerror(ret)); + + r = set_ensure_put(&w->peers_with_failed_endpoint, NULL, peer); + if (r < 0) { + log_netdev_error(netdev, "Failed to save a peer, dropping the peer: %m"); + peer->section->invalid = true; + goto resolve_next; + } + + } else if ((ai->ai_family == AF_INET && ai->ai_addrlen == sizeof(struct sockaddr_in)) || + (ai->ai_family == AF_INET6 && ai->ai_addrlen == sizeof(struct sockaddr_in6))) + memcpy(&peer->endpoint, ai->ai_addr, ai->ai_addrlen); + else + log_netdev_error(netdev, "Neither IPv4 nor IPv6 address found for peer endpoint %s:%s, ignoring the address.", + peer->endpoint_host, peer->endpoint_port); + +resolve_next: + if (!set_isempty(w->peers_with_unresolved_endpoint)) { + resolve_endpoints(netdev); + return 0; + } + + (void) wireguard_set_interface(netdev); + + if (!set_isempty(w->peers_with_failed_endpoint)) { + usec_t usec; + + w->n_retries++; + usec = usec_add(now(CLOCK_MONOTONIC), exponential_backoff_milliseconds(w->n_retries)); + r = event_reset_time(netdev->manager->event, &w->resolve_retry_event_source, + CLOCK_MONOTONIC, usec, 0, on_resolve_retry, netdev, + 0, "wireguard-resolve-retry", true); + if (r < 0) { + log_netdev_warning_errno(netdev, r, "Could not arm resolve retry handler: %m"); + return 0; + } + } + + return 0; +} + +static void resolve_endpoints(NetDev *netdev) { + static const struct addrinfo hints = { + .ai_family = AF_UNSPEC, + .ai_socktype = SOCK_DGRAM, + .ai_protocol = IPPROTO_UDP + }; + WireguardPeer *peer; + Wireguard *w; + int r; + + assert(netdev); + w = WIREGUARD(netdev); + assert(w); + + SET_FOREACH(peer, w->peers_with_unresolved_endpoint) { + r = resolve_getaddrinfo(netdev->manager->resolve, + NULL, + peer->endpoint_host, + peer->endpoint_port, + &hints, + wireguard_resolve_handler, + wireguard_peer_destroy_callback, + peer); + if (r == -ENOBUFS) + break; + if (r < 0) { + log_netdev_error_errno(netdev, r, "Failed to create resolver: %m"); + continue; + } + + /* Avoid freeing netdev. It will be unrefed by the destroy callback. */ + netdev_ref(netdev); + + (void) set_remove(w->peers_with_unresolved_endpoint, peer); + } +} + +static int netdev_wireguard_post_create(NetDev *netdev, Link *link, sd_netlink_message *m) { + assert(netdev); + assert(WIREGUARD(netdev)); + + (void) wireguard_set_interface(netdev); + resolve_endpoints(netdev); + return 0; +} + +int config_parse_wireguard_listen_port( + 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) { + + uint16_t *s = data; + int r; + + assert(rvalue); + assert(data); + + if (isempty(rvalue) || streq(rvalue, "auto")) { + *s = 0; + return 0; + } + + r = parse_ip_port(rvalue, s); + if (r < 0) { + log_syntax(unit, LOG_WARNING, filename, line, r, + "Invalid port specification, ignoring assignment: %s", rvalue); + return 0; + } + + return 0; +} + +static int wireguard_decode_key_and_warn( + const char *rvalue, + uint8_t ret[static WG_KEY_LEN], + const char *unit, + const char *filename, + unsigned line, + const char *lvalue) { + + _cleanup_(erase_and_freep) void *key = NULL; + size_t len; + int r; + + assert(rvalue); + assert(ret); + assert(filename); + assert(lvalue); + + if (isempty(rvalue)) { + memzero(ret, WG_KEY_LEN); + return 0; + } + + if (!streq(lvalue, "PublicKey")) + (void) warn_file_is_world_accessible(filename, NULL, unit, line); + + r = unbase64mem_full(rvalue, strlen(rvalue), true, &key, &len); + if (r == -ENOMEM) + return log_oom(); + if (r < 0) { + log_syntax(unit, LOG_WARNING, filename, line, r, + "Failed to decode wireguard key provided by %s=, ignoring assignment: %m", lvalue); + return 0; + } + if (len != WG_KEY_LEN) { + log_syntax(unit, LOG_WARNING, filename, line, 0, + "Wireguard key provided by %s= has invalid length (%zu bytes), ignoring assignment.", + lvalue, len); + return 0; + } + + memcpy(ret, key, WG_KEY_LEN); + return 0; +} + +int config_parse_wireguard_private_key( + 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) { + + Wireguard *w; + + assert(data); + w = WIREGUARD(data); + assert(w); + + return wireguard_decode_key_and_warn(rvalue, w->private_key, unit, filename, line, lvalue); +} + +int config_parse_wireguard_private_key_file( + 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) { + + _cleanup_free_ char *path = NULL; + Wireguard *w; + + assert(data); + w = WIREGUARD(data); + assert(w); + + if (isempty(rvalue)) { + w->private_key_file = mfree(w->private_key_file); + return 0; + } + + path = strdup(rvalue); + if (!path) + return log_oom(); + + if (path_simplify_and_warn(path, PATH_CHECK_ABSOLUTE, unit, filename, line, lvalue) < 0) + return 0; + + return free_and_replace(w->private_key_file, path); +} + +int config_parse_wireguard_peer_key( + 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) { + + _cleanup_(wireguard_peer_free_or_set_invalidp) WireguardPeer *peer = NULL; + Wireguard *w; + int r; + + assert(data); + w = WIREGUARD(data); + assert(w); + + r = wireguard_peer_new_static(w, filename, section_line, &peer); + if (r < 0) + return log_oom(); + + r = wireguard_decode_key_and_warn(rvalue, + streq(lvalue, "PublicKey") ? peer->public_key : peer->preshared_key, + unit, filename, line, lvalue); + if (r < 0) + return r; + + TAKE_PTR(peer); + return 0; +} + +int config_parse_wireguard_preshared_key_file( + 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) { + + _cleanup_(wireguard_peer_free_or_set_invalidp) WireguardPeer *peer = NULL; + _cleanup_free_ char *path = NULL; + Wireguard *w; + int r; + + assert(data); + w = WIREGUARD(data); + assert(w); + + r = wireguard_peer_new_static(w, filename, section_line, &peer); + if (r < 0) + return log_oom(); + + if (isempty(rvalue)) { + peer->preshared_key_file = mfree(peer->preshared_key_file); + TAKE_PTR(peer); + return 0; + } + + path = strdup(rvalue); + if (!path) + return log_oom(); + + if (path_simplify_and_warn(path, PATH_CHECK_ABSOLUTE, unit, filename, line, lvalue) < 0) + return 0; + + free_and_replace(peer->preshared_key_file, path); + TAKE_PTR(peer); + return 0; +} + +int config_parse_wireguard_allowed_ips( + 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) { + + _cleanup_(wireguard_peer_free_or_set_invalidp) WireguardPeer *peer = NULL; + union in_addr_union addr; + unsigned char prefixlen; + int r, family; + Wireguard *w; + WireguardIPmask *ipmask; + + assert(rvalue); + assert(data); + + w = WIREGUARD(data); + assert(w); + + r = wireguard_peer_new_static(w, filename, section_line, &peer); + if (r < 0) + return log_oom(); + + for (const char *p = rvalue;;) { + _cleanup_free_ char *word = NULL; + + r = extract_first_word(&p, &word, "," WHITESPACE, 0); + if (r == 0) + break; + if (r == -ENOMEM) + return log_oom(); + if (r < 0) { + log_syntax(unit, LOG_WARNING, filename, line, r, + "Failed to split allowed ips \"%s\" option: %m", rvalue); + break; + } + + r = in_addr_prefix_from_string_auto(word, &family, &addr, &prefixlen); + if (r < 0) { + log_syntax(unit, LOG_WARNING, filename, line, r, + "Network address is invalid, ignoring assignment: %s", word); + continue; + } + + ipmask = new(WireguardIPmask, 1); + if (!ipmask) + return log_oom(); + + *ipmask = (WireguardIPmask) { + .family = family, + .ip.in6 = addr.in6, + .cidr = prefixlen, + }; + + LIST_PREPEND(ipmasks, peer->ipmasks, ipmask); + } + + TAKE_PTR(peer); + return 0; +} + +int config_parse_wireguard_endpoint( + 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) { + + _cleanup_(wireguard_peer_free_or_set_invalidp) WireguardPeer *peer = NULL; + const char *begin, *end; + Wireguard *w; + size_t len; + int r; + + assert(data); + assert(rvalue); + + w = WIREGUARD(data); + assert(w); + + if (rvalue[0] == '[') { + begin = &rvalue[1]; + end = strchr(rvalue, ']'); + if (!end) { + log_syntax(unit, LOG_WARNING, filename, line, 0, + "Unable to find matching brace of endpoint, ignoring assignment: %s", + rvalue); + return 0; + } + len = end - begin; + ++end; + if (*end != ':' || !*(end + 1)) { + log_syntax(unit, LOG_WARNING, filename, line, 0, + "Unable to find port of endpoint, ignoring assignment: %s", + rvalue); + return 0; + } + ++end; + } else { + begin = rvalue; + end = strrchr(rvalue, ':'); + if (!end || !*(end + 1)) { + log_syntax(unit, LOG_WARNING, filename, line, 0, + "Unable to find port of endpoint, ignoring assignment: %s", + rvalue); + return 0; + } + len = end - begin; + ++end; + } + + r = wireguard_peer_new_static(w, filename, section_line, &peer); + if (r < 0) + return log_oom(); + + r = free_and_strndup(&peer->endpoint_host, begin, len); + if (r < 0) + return log_oom(); + + r = free_and_strdup(&peer->endpoint_port, end); + if (r < 0) + return log_oom(); + + r = set_ensure_put(&w->peers_with_unresolved_endpoint, NULL, peer); + if (r < 0) + return log_oom(); + TAKE_PTR(peer); /* The peer may already have been in the hash map, that is fine too. */ + + return 0; +} + +int config_parse_wireguard_keepalive( + 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) { + + _cleanup_(wireguard_peer_free_or_set_invalidp) WireguardPeer *peer = NULL; + uint16_t keepalive = 0; + Wireguard *w; + int r; + + assert(rvalue); + assert(data); + + w = WIREGUARD(data); + assert(w); + + r = wireguard_peer_new_static(w, filename, section_line, &peer); + if (r < 0) + return log_oom(); + + if (streq(rvalue, "off")) + keepalive = 0; + else { + r = safe_atou16(rvalue, &keepalive); + if (r < 0) { + log_syntax(unit, LOG_WARNING, filename, line, r, + "Failed to parse \"%s\" as keepalive interval (range 0–65535), ignoring assignment: %m", + rvalue); + return 0; + } + } + + peer->persistent_keepalive_interval = keepalive; + + TAKE_PTR(peer); + return 0; +} + +static void wireguard_init(NetDev *netdev) { + Wireguard *w; + + assert(netdev); + w = WIREGUARD(netdev); + assert(w); + + w->flags = WGDEVICE_F_REPLACE_PEERS; +} + +static void wireguard_done(NetDev *netdev) { + Wireguard *w; + + assert(netdev); + w = WIREGUARD(netdev); + assert(w); + + sd_event_source_unref(w->resolve_retry_event_source); + + explicit_bzero_safe(w->private_key, WG_KEY_LEN); + free(w->private_key_file); + + hashmap_free_with_destructor(w->peers_by_section, wireguard_peer_free); + set_free(w->peers_with_unresolved_endpoint); + set_free(w->peers_with_failed_endpoint); +} + +static int wireguard_read_key_file(const char *filename, uint8_t dest[static WG_KEY_LEN]) { + _cleanup_(erase_and_freep) char *key = NULL; + size_t key_len; + int r; + + if (!filename) + return 0; + + assert(dest); + + (void) warn_file_is_world_accessible(filename, NULL, NULL, 0); + + r = read_full_file_full( + AT_FDCWD, filename, + READ_FULL_FILE_SECURE | READ_FULL_FILE_UNBASE64 | READ_FULL_FILE_WARN_WORLD_READABLE | READ_FULL_FILE_CONNECT_SOCKET, + NULL, &key, &key_len); + if (r < 0) + return r; + + if (key_len != WG_KEY_LEN) + return -EINVAL; + + memcpy(dest, key, WG_KEY_LEN); + return 0; +} + +static int wireguard_peer_verify(WireguardPeer *peer) { + NetDev *netdev = NETDEV(peer->wireguard); + int r; + + if (section_is_invalid(peer->section)) + return -EINVAL; + + if (eqzero(peer->public_key)) + return log_netdev_error_errno(netdev, SYNTHETIC_ERRNO(EINVAL), + "%s: WireGuardPeer section without PublicKey= configured. " + "Ignoring [WireGuardPeer] section from line %u.", + peer->section->filename, peer->section->line); + + r = wireguard_read_key_file(peer->preshared_key_file, peer->preshared_key); + if (r < 0) + return log_netdev_error_errno(netdev, r, + "%s: Failed to read preshared key from '%s'. " + "Ignoring [WireGuardPeer] section from line %u.", + peer->section->filename, peer->preshared_key_file, + peer->section->line); + + return 0; +} + +static int wireguard_verify(NetDev *netdev, const char *filename) { + WireguardPeer *peer, *peer_next; + Wireguard *w; + int r; + + assert(netdev); + w = WIREGUARD(netdev); + assert(w); + + r = wireguard_read_key_file(w->private_key_file, w->private_key); + if (r < 0) + return log_netdev_error_errno(netdev, r, + "Failed to read private key from %s. Dropping network device %s.", + w->private_key_file, netdev->ifname); + + if (eqzero(w->private_key)) + return log_netdev_error_errno(netdev, SYNTHETIC_ERRNO(EINVAL), + "%s: Missing PrivateKey= or PrivateKeyFile=, " + "Dropping network device %s.", + filename, netdev->ifname); + + LIST_FOREACH_SAFE(peers, peer, peer_next, w->peers) + if (wireguard_peer_verify(peer) < 0) + wireguard_peer_free(peer); + + return 0; +} + +const NetDevVTable wireguard_vtable = { + .object_size = sizeof(Wireguard), + .sections = NETDEV_COMMON_SECTIONS "WireGuard\0WireGuardPeer\0", + .post_create = netdev_wireguard_post_create, + .init = wireguard_init, + .done = wireguard_done, + .create_type = NETDEV_CREATE_INDEPENDENT, + .config_verify = wireguard_verify, + .generate_mac = true, +}; |