| /* SPDX-License-Identifier: LGPL-2.1+ */ |
| |
| #include "sd-netlink.h" |
| |
| #include "format-util.h" |
| #include "memory-util.h" |
| #include "netlink-internal.h" |
| #include "netlink-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; |
| char old_name[IF_NAMESIZE + 1] = {}; |
| 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); |
| |
| format_ifname(ifindex, old_name); |
| } |
| |
| r = sd_rtnl_message_new_link(*rtnl, &message, RTM_SETLINK, ifindex); |
| if (r < 0) |
| return r; |
| |
| r = sd_netlink_message_append_string(message, IFLA_IFNAME, name); |
| if (r < 0) |
| return r; |
| |
| r = sd_netlink_call(*rtnl, message, 0, NULL); |
| if (r < 0) |
| return r; |
| |
| if (!isempty(old_name)) { |
| r = rtnl_set_link_alternative_names(rtnl, ifindex, STRV_MAKE(old_name)); |
| if (r < 0) |
| log_debug_errno(r, "Failed to set '%s' as an alternative name on network interface %i, ignoring: %m", |
| old_name, ifindex); |
| } |
| |
| return 0; |
| } |
| |
| int rtnl_set_link_properties(sd_netlink **rtnl, int ifindex, const char *alias, |
| const struct ether_addr *mac, uint32_t mtu) { |
| _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL; |
| int r; |
| |
| assert(rtnl); |
| assert(ifindex > 0); |
| |
| if (!alias && !mac && mtu == 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 (mac) { |
| r = sd_netlink_message_append_ether_addr(message, IFLA_ADDRESS, mac); |
| if (r < 0) |
| return r; |
| } |
| |
| if (mtu != 0) { |
| r = sd_netlink_message_append_u32(message, IFLA_MTU, mtu); |
| 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, 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, 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) { |
| _cleanup_(sd_netlink_unrefp) sd_netlink *our_rtnl = NULL; |
| _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL, *reply = NULL; |
| int r, ret; |
| |
| assert(name); |
| |
| 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, &ret); |
| if (r < 0) |
| return r; |
| assert(ret > 0); |
| return ret; |
| } |
| |
| int rtnl_get_link_iftype(sd_netlink **rtnl, int ifindex, unsigned short *ret) { |
| _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *message = NULL, *reply = NULL; |
| int r; |
| |
| 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; |
| |
| return sd_rtnl_message_link_get_type(reply, ret); |
| } |
| |
| int rtnl_message_new_synthetic_error(sd_netlink *rtnl, int error, uint32_t serial, sd_netlink_message **ret) { |
| struct nlmsgerr *err; |
| int r; |
| |
| assert(error <= 0); |
| |
| r = message_new(rtnl, ret, NLMSG_ERROR); |
| if (r < 0) |
| return r; |
| |
| rtnl_message_seal(*ret); |
| (*ret)->hdr->nlmsg_seq = serial; |
| |
| err = NLMSG_DATA((*ret)->hdr); |
| err->error = error; |
| |
| 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; |
| } |