blob: 6cd916a2097b484f3d6a116d34cf6ca34d1523d2 [file] [log] [blame]
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include "sd-netlink.h"
#include "fd-util.h"
#include "io-util.h"
#include "memory-util.h"
#include "netlink-internal.h"
#include "netlink-util.h"
#include "parse-util.h"
#include "process-util.h"
#include "strv.h"
int rtnl_set_link_name(sd_netlink **rtnl, int ifindex, const char *name) {
_cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL;
_cleanup_strv_free_ char **alternative_names = NULL;
bool altname_deleted = false;
int r;
assert(rtnl);
assert(ifindex > 0);
assert(name);
if (!ifname_valid(name))
return -EINVAL;
r = rtnl_get_link_alternative_names(rtnl, ifindex, &alternative_names);
if (r < 0)
log_debug_errno(r, "Failed to get alternative names on network interface %i, ignoring: %m",
ifindex);
if (strv_contains(alternative_names, name)) {
r = rtnl_delete_link_alternative_names(rtnl, ifindex, STRV_MAKE(name));
if (r < 0)
return log_debug_errno(r, "Failed to remove '%s' from alternative names on network interface %i: %m",
name, ifindex);
altname_deleted = true;
}
r = sd_rtnl_message_new_link(*rtnl, &message, RTM_SETLINK, ifindex);
if (r < 0)
goto fail;
r = sd_netlink_message_append_string(message, IFLA_IFNAME, name);
if (r < 0)
goto fail;
r = sd_netlink_call(*rtnl, message, 0, NULL);
if (r < 0)
goto fail;
return 0;
fail:
if (altname_deleted) {
int q = rtnl_set_link_alternative_names(rtnl, ifindex, STRV_MAKE(name));
if (q < 0)
log_debug_errno(q, "Failed to restore '%s' as an alternative name on network interface %i, ignoring: %m",
name, ifindex);
}
return r;
}
int rtnl_set_link_properties(
sd_netlink **rtnl,
int ifindex,
const char *alias,
const struct hw_addr_data *hw_addr,
uint32_t txqueues,
uint32_t rxqueues,
uint32_t txqueuelen,
uint32_t mtu,
uint32_t gso_max_size,
size_t gso_max_segments) {
_cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL;
int r;
assert(rtnl);
assert(ifindex > 0);
if (!alias &&
(!hw_addr || hw_addr->length == 0) &&
txqueues == 0 &&
rxqueues == 0 &&
txqueuelen == UINT32_MAX &&
mtu == 0 &&
gso_max_size == 0 &&
gso_max_segments == 0)
return 0;
if (!*rtnl) {
r = sd_netlink_open(rtnl);
if (r < 0)
return r;
}
r = sd_rtnl_message_new_link(*rtnl, &message, RTM_SETLINK, ifindex);
if (r < 0)
return r;
if (alias) {
r = sd_netlink_message_append_string(message, IFLA_IFALIAS, alias);
if (r < 0)
return r;
}
if (hw_addr && hw_addr->length > 0) {
r = netlink_message_append_hw_addr(message, IFLA_ADDRESS, hw_addr);
if (r < 0)
return r;
}
if (txqueues > 0) {
r = sd_netlink_message_append_u32(message, IFLA_NUM_TX_QUEUES, txqueues);
if (r < 0)
return r;
}
if (rxqueues > 0) {
r = sd_netlink_message_append_u32(message, IFLA_NUM_RX_QUEUES, rxqueues);
if (r < 0)
return r;
}
if (txqueuelen < UINT32_MAX) {
r = sd_netlink_message_append_u32(message, IFLA_TXQLEN, txqueuelen);
if (r < 0)
return r;
}
if (mtu != 0) {
r = sd_netlink_message_append_u32(message, IFLA_MTU, mtu);
if (r < 0)
return r;
}
if (gso_max_size > 0) {
r = sd_netlink_message_append_u32(message, IFLA_GSO_MAX_SIZE, gso_max_size);
if (r < 0)
return r;
}
if (gso_max_segments > 0) {
r = sd_netlink_message_append_u32(message, IFLA_GSO_MAX_SEGS, gso_max_segments);
if (r < 0)
return r;
}
r = sd_netlink_call(*rtnl, message, 0, NULL);
if (r < 0)
return r;
return 0;
}
int rtnl_get_link_alternative_names(sd_netlink **rtnl, int ifindex, char ***ret) {
_cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL, *reply = NULL;
_cleanup_strv_free_ char **names = NULL;
int r;
assert(rtnl);
assert(ifindex > 0);
assert(ret);
if (!*rtnl) {
r = sd_netlink_open(rtnl);
if (r < 0)
return r;
}
r = sd_rtnl_message_new_link(*rtnl, &message, RTM_GETLINK, ifindex);
if (r < 0)
return r;
r = sd_netlink_call(*rtnl, message, 0, &reply);
if (r < 0)
return r;
r = sd_netlink_message_read_strv(reply, IFLA_PROP_LIST, IFLA_ALT_IFNAME, &names);
if (r < 0 && r != -ENODATA)
return r;
*ret = TAKE_PTR(names);
return 0;
}
static int rtnl_update_link_alternative_names(
sd_netlink **rtnl,
uint16_t nlmsg_type,
int ifindex,
char* const *alternative_names) {
_cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL;
int r;
assert(rtnl);
assert(ifindex > 0);
assert(IN_SET(nlmsg_type, RTM_NEWLINKPROP, RTM_DELLINKPROP));
if (strv_isempty(alternative_names))
return 0;
if (!*rtnl) {
r = sd_netlink_open(rtnl);
if (r < 0)
return r;
}
r = sd_rtnl_message_new_link(*rtnl, &message, nlmsg_type, ifindex);
if (r < 0)
return r;
r = sd_netlink_message_open_container(message, IFLA_PROP_LIST);
if (r < 0)
return r;
r = sd_netlink_message_append_strv(message, IFLA_ALT_IFNAME, (const char**) alternative_names);
if (r < 0)
return r;
r = sd_netlink_message_close_container(message);
if (r < 0)
return r;
r = sd_netlink_call(*rtnl, message, 0, NULL);
if (r < 0)
return r;
return 0;
}
int rtnl_set_link_alternative_names(sd_netlink **rtnl, int ifindex, char* const *alternative_names) {
return rtnl_update_link_alternative_names(rtnl, RTM_NEWLINKPROP, ifindex, alternative_names);
}
int rtnl_delete_link_alternative_names(sd_netlink **rtnl, int ifindex, char* const *alternative_names) {
return rtnl_update_link_alternative_names(rtnl, RTM_DELLINKPROP, ifindex, alternative_names);
}
int rtnl_set_link_alternative_names_by_ifname(
sd_netlink **rtnl,
const char *ifname,
char* const *alternative_names) {
_cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL;
int r;
assert(rtnl);
assert(ifname);
if (strv_isempty(alternative_names))
return 0;
if (!*rtnl) {
r = sd_netlink_open(rtnl);
if (r < 0)
return r;
}
r = sd_rtnl_message_new_link(*rtnl, &message, RTM_NEWLINKPROP, 0);
if (r < 0)
return r;
r = sd_netlink_message_append_string(message, IFLA_IFNAME, ifname);
if (r < 0)
return r;
r = sd_netlink_message_open_container(message, IFLA_PROP_LIST);
if (r < 0)
return r;
r = sd_netlink_message_append_strv(message, IFLA_ALT_IFNAME, (const char**) alternative_names);
if (r < 0)
return r;
r = sd_netlink_message_close_container(message);
if (r < 0)
return r;
r = sd_netlink_call(*rtnl, message, 0, NULL);
if (r < 0)
return r;
return 0;
}
int rtnl_resolve_link_alternative_name(sd_netlink **rtnl, const char *name, char **ret) {
_cleanup_(sd_netlink_unrefp) sd_netlink *our_rtnl = NULL;
_cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL, *reply = NULL;
int r, ifindex;
assert(name);
/* This returns ifindex and the main interface name. */
if (!ifname_valid_full(name, IFNAME_VALID_ALTERNATIVE))
return -EINVAL;
if (!rtnl)
rtnl = &our_rtnl;
if (!*rtnl) {
r = sd_netlink_open(rtnl);
if (r < 0)
return r;
}
r = sd_rtnl_message_new_link(*rtnl, &message, RTM_GETLINK, 0);
if (r < 0)
return r;
r = sd_netlink_message_append_string(message, IFLA_ALT_IFNAME, name);
if (r < 0)
return r;
r = sd_netlink_call(*rtnl, message, 0, &reply);
if (r == -EINVAL)
return -ENODEV; /* The device doesn't exist */
if (r < 0)
return r;
r = sd_rtnl_message_link_get_ifindex(reply, &ifindex);
if (r < 0)
return r;
assert(ifindex > 0);
if (ret) {
r = sd_netlink_message_read_string_strdup(message, IFLA_IFNAME, ret);
if (r < 0)
return r;
}
return ifindex;
}
int rtnl_resolve_ifname(sd_netlink **rtnl, const char *name) {
int r;
/* Like if_nametoindex, but resolves "alternative names" too. */
assert(name);
r = if_nametoindex(name);
if (r > 0)
return r;
return rtnl_resolve_link_alternative_name(rtnl, name, NULL);
}
int rtnl_resolve_interface(sd_netlink **rtnl, const char *name) {
int r;
/* Like rtnl_resolve_ifname, but resolves interface numbers too. */
assert(name);
r = parse_ifindex(name);
if (r > 0)
return r;
assert(r < 0);
return rtnl_resolve_ifname(rtnl, name);
}
int rtnl_resolve_interface_or_warn(sd_netlink **rtnl, const char *name) {
int r;
r = rtnl_resolve_interface(rtnl, name);
if (r < 0)
return log_error_errno(r, "Failed to resolve interface \"%s\": %m", name);
return r;
}
int rtnl_get_link_info(
sd_netlink **rtnl,
int ifindex,
unsigned short *ret_iftype,
unsigned *ret_flags,
char **ret_kind,
struct hw_addr_data *ret_hw_addr,
struct hw_addr_data *ret_permanent_hw_addr) {
_cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL, *reply = NULL;
struct hw_addr_data addr = HW_ADDR_NULL, perm_addr = HW_ADDR_NULL;
_cleanup_free_ char *kind = NULL;
unsigned short iftype;
unsigned flags;
int r;
assert(rtnl);
assert(ifindex > 0);
if (!ret_iftype && !ret_flags)
return 0;
if (!*rtnl) {
r = sd_netlink_open(rtnl);
if (r < 0)
return r;
}
r = sd_rtnl_message_new_link(*rtnl, &message, RTM_GETLINK, ifindex);
if (r < 0)
return r;
r = sd_netlink_call(*rtnl, message, 0, &reply);
if (r == -EINVAL)
return -ENODEV; /* The device does not exist */
if (r < 0)
return r;
if (ret_iftype) {
r = sd_rtnl_message_link_get_type(reply, &iftype);
if (r < 0)
return r;
}
if (ret_flags) {
r = sd_rtnl_message_link_get_flags(reply, &flags);
if (r < 0)
return r;
}
if (ret_kind) {
r = sd_netlink_message_enter_container(reply, IFLA_LINKINFO);
if (r >= 0) {
r = sd_netlink_message_read_string_strdup(reply, IFLA_INFO_KIND, &kind);
if (r < 0 && r != -ENODATA)
return r;
r = sd_netlink_message_exit_container(reply);
if (r < 0)
return r;
}
}
if (ret_hw_addr) {
r = netlink_message_read_hw_addr(reply, IFLA_ADDRESS, &addr);
if (r < 0 && r != -ENODATA)
return r;
}
if (ret_permanent_hw_addr) {
r = netlink_message_read_hw_addr(reply, IFLA_PERM_ADDRESS, &perm_addr);
if (r < 0 && r != -ENODATA)
return r;
}
if (ret_iftype)
*ret_iftype = iftype;
if (ret_flags)
*ret_flags = flags;
if (ret_kind)
*ret_kind = TAKE_PTR(kind);
if (ret_hw_addr)
*ret_hw_addr = addr;
if (ret_permanent_hw_addr)
*ret_permanent_hw_addr = perm_addr;
return 0;
}
int rtnl_log_parse_error(int r) {
return log_error_errno(r, "Failed to parse netlink message: %m");
}
int rtnl_log_create_error(int r) {
return log_error_errno(r, "Failed to create netlink message: %m");
}
void rtattr_append_attribute_internal(struct rtattr *rta, unsigned short type, const void *data, size_t data_length) {
size_t padding_length;
uint8_t *padding;
assert(rta);
assert(!data || data_length > 0);
/* fill in the attribute */
rta->rta_type = type;
rta->rta_len = RTA_LENGTH(data_length);
if (data)
/* we don't deal with the case where the user lies about the type
* and gives us too little data (so don't do that)
*/
padding = mempcpy(RTA_DATA(rta), data, data_length);
else
/* if no data was passed, make sure we still initialize the padding
note that we can have data_length > 0 (used by some containers) */
padding = RTA_DATA(rta);
/* make sure also the padding at the end of the message is initialized */
padding_length = (uint8_t *) rta + RTA_SPACE(data_length) - padding;
memzero(padding, padding_length);
}
int rtattr_append_attribute(struct rtattr **rta, unsigned short type, const void *data, size_t data_length) {
struct rtattr *new_rta, *sub_rta;
size_t message_length;
assert(rta);
assert(!data || data_length > 0);
/* get the new message size (with padding at the end) */
message_length = RTA_ALIGN(rta ? (*rta)->rta_len : 0) + RTA_SPACE(data_length);
/* buffer should be smaller than both one page or 8K to be accepted by the kernel */
if (message_length > MIN(page_size(), 8192UL))
return -ENOBUFS;
/* realloc to fit the new attribute */
new_rta = realloc(*rta, message_length);
if (!new_rta)
return -ENOMEM;
*rta = new_rta;
/* get pointer to the attribute we are about to add */
sub_rta = (struct rtattr *) ((uint8_t *) *rta + RTA_ALIGN((*rta)->rta_len));
rtattr_append_attribute_internal(sub_rta, type, data, data_length);
/* update rta_len */
(*rta)->rta_len = message_length;
return 0;
}
MultipathRoute *multipath_route_free(MultipathRoute *m) {
if (!m)
return NULL;
free(m->ifname);
return mfree(m);
}
int multipath_route_dup(const MultipathRoute *m, MultipathRoute **ret) {
_cleanup_(multipath_route_freep) MultipathRoute *n = NULL;
_cleanup_free_ char *ifname = NULL;
assert(m);
assert(ret);
if (m->ifname) {
ifname = strdup(m->ifname);
if (!ifname)
return -ENOMEM;
}
n = new(MultipathRoute, 1);
if (!n)
return -ENOMEM;
*n = (MultipathRoute) {
.gateway = m->gateway,
.weight = m->weight,
.ifindex = m->ifindex,
.ifname = TAKE_PTR(ifname),
};
*ret = TAKE_PTR(n);
return 0;
}
int rtattr_read_nexthop(const struct rtnexthop *rtnh, size_t size, int family, OrderedSet **ret) {
_cleanup_ordered_set_free_free_ OrderedSet *set = NULL;
int r;
assert(rtnh);
assert(IN_SET(family, AF_INET, AF_INET6));
if (size < sizeof(struct rtnexthop))
return -EBADMSG;
for (; size >= sizeof(struct rtnexthop); ) {
_cleanup_(multipath_route_freep) MultipathRoute *m = NULL;
if (NLMSG_ALIGN(rtnh->rtnh_len) > size)
return -EBADMSG;
if (rtnh->rtnh_len < sizeof(struct rtnexthop))
return -EBADMSG;
m = new(MultipathRoute, 1);
if (!m)
return -ENOMEM;
*m = (MultipathRoute) {
.ifindex = rtnh->rtnh_ifindex,
.weight = rtnh->rtnh_hops,
};
if (rtnh->rtnh_len > sizeof(struct rtnexthop)) {
size_t len = rtnh->rtnh_len - sizeof(struct rtnexthop);
for (struct rtattr *attr = RTNH_DATA(rtnh); RTA_OK(attr, len); attr = RTA_NEXT(attr, len)) {
if (attr->rta_type == RTA_GATEWAY) {
if (attr->rta_len != RTA_LENGTH(FAMILY_ADDRESS_SIZE(family)))
return -EBADMSG;
m->gateway.family = family;
memcpy(&m->gateway.address, RTA_DATA(attr), FAMILY_ADDRESS_SIZE(family));
break;
} else if (attr->rta_type == RTA_VIA) {
uint16_t gw_family;
if (family != AF_INET)
return -EINVAL;
if (attr->rta_len < RTA_LENGTH(sizeof(uint16_t)))
return -EBADMSG;
gw_family = *(uint16_t *) RTA_DATA(attr);
if (gw_family != AF_INET6)
return -EBADMSG;
if (attr->rta_len != RTA_LENGTH(FAMILY_ADDRESS_SIZE(gw_family) + sizeof(gw_family)))
return -EBADMSG;
memcpy(&m->gateway, RTA_DATA(attr), FAMILY_ADDRESS_SIZE(gw_family) + sizeof(gw_family));
break;
}
}
}
r = ordered_set_ensure_put(&set, NULL, m);
if (r < 0)
return r;
TAKE_PTR(m);
size -= NLMSG_ALIGN(rtnh->rtnh_len);
rtnh = RTNH_NEXT(rtnh);
}
if (ret)
*ret = TAKE_PTR(set);
return 0;
}
bool netlink_pid_changed(sd_netlink *nl) {
/* We don't support people creating an nl connection and
* keeping it around over a fork(). Let's complain. */
return ASSERT_PTR(nl)->original_pid != getpid_cached();
}
static int socket_open(int family) {
int fd;
fd = socket(AF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, family);
if (fd < 0)
return -errno;
return fd_move_above_stdio(fd);
}
int netlink_open_family(sd_netlink **ret, int family) {
_cleanup_close_ int fd = -EBADF;
int r;
fd = socket_open(family);
if (fd < 0)
return fd;
r = sd_netlink_open_fd(ret, fd);
if (r < 0)
return r;
TAKE_FD(fd);
return 0;
}
static bool serial_used(sd_netlink *nl, uint32_t serial) {
assert(nl);
return
hashmap_contains(nl->reply_callbacks, UINT32_TO_PTR(serial)) ||
hashmap_contains(nl->rqueue_by_serial, UINT32_TO_PTR(serial)) ||
hashmap_contains(nl->rqueue_partial_by_serial, UINT32_TO_PTR(serial));
}
void netlink_seal_message(sd_netlink *nl, sd_netlink_message *m) {
uint32_t picked;
assert(nl);
assert(!netlink_pid_changed(nl));
assert(m);
assert(m->hdr);
/* Avoid collisions with outstanding requests */
do {
picked = nl->serial;
/* Don't use seq == 0, as that is used for broadcasts, so we would get confused by replies to
such messages */
nl->serial = nl->serial == UINT32_MAX ? 1 : nl->serial + 1;
} while (serial_used(nl, picked));
m->hdr->nlmsg_seq = picked;
message_seal(m);
}
static int socket_writev_message(sd_netlink *nl, sd_netlink_message **m, size_t msgcount) {
_cleanup_free_ struct iovec *iovs = NULL;
ssize_t k;
assert(nl);
assert(m);
assert(msgcount > 0);
iovs = new(struct iovec, msgcount);
if (!iovs)
return -ENOMEM;
for (size_t i = 0; i < msgcount; i++) {
assert(m[i]->hdr);
assert(m[i]->hdr->nlmsg_len > 0);
iovs[i] = IOVEC_MAKE(m[i]->hdr, m[i]->hdr->nlmsg_len);
}
k = writev(nl->fd, iovs, msgcount);
if (k < 0)
return -errno;
return k;
}
int sd_netlink_sendv(
sd_netlink *nl,
sd_netlink_message **messages,
size_t msgcount,
uint32_t **ret_serial) {
_cleanup_free_ uint32_t *serials = NULL;
int r;
assert_return(nl, -EINVAL);
assert_return(!netlink_pid_changed(nl), -ECHILD);
assert_return(messages, -EINVAL);
assert_return(msgcount > 0, -EINVAL);
if (ret_serial) {
serials = new(uint32_t, msgcount);
if (!serials)
return -ENOMEM;
}
for (size_t i = 0; i < msgcount; i++) {
assert_return(!messages[i]->sealed, -EPERM);
netlink_seal_message(nl, messages[i]);
if (serials)
serials[i] = message_get_serial(messages[i]);
}
r = socket_writev_message(nl, messages, msgcount);
if (r < 0)
return r;
if (ret_serial)
*ret_serial = TAKE_PTR(serials);
return r;
}