| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <linux/genetlink.h> |
| |
| #include "sd-netlink.h" |
| |
| #include "alloc-util.h" |
| #include "generic-netlink.h" |
| #include "netlink-internal.h" |
| |
| typedef struct { |
| const char* name; |
| uint8_t version; |
| } genl_family; |
| |
| static const genl_family genl_families[] = { |
| [SD_GENL_ID_CTRL] = { .name = "", .version = 1 }, |
| [SD_GENL_WIREGUARD] = { .name = "wireguard", .version = 1 }, |
| [SD_GENL_FOU] = { .name = "fou", .version = 1 }, |
| [SD_GENL_L2TP] = { .name = "l2tp", .version = 1 }, |
| [SD_GENL_MACSEC] = { .name = "macsec", .version = 1 }, |
| [SD_GENL_NL80211] = { .name = "nl80211", .version = 1 }, |
| [SD_GENL_BATADV] = { .name = "batadv", .version = 1 }, |
| }; |
| |
| int sd_genl_socket_open(sd_netlink **ret) { |
| return netlink_open_family(ret, NETLINK_GENERIC); |
| } |
| |
| static int genl_message_new(sd_netlink *nl, sd_genl_family_t family, uint16_t nlmsg_type, uint8_t cmd, sd_netlink_message **ret) { |
| _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL; |
| const NLType *genl_cmd_type, *nl_type; |
| const NLTypeSystem *type_system; |
| size_t size; |
| int r; |
| |
| assert(nl); |
| assert(nl->protocol == NETLINK_GENERIC); |
| assert(ret); |
| |
| r = type_system_get_type(&genl_family_type_system_root, &genl_cmd_type, family); |
| if (r < 0) |
| return r; |
| |
| r = message_new_empty(nl, &m); |
| if (r < 0) |
| return r; |
| |
| size = NLMSG_SPACE(sizeof(struct genlmsghdr)); |
| m->hdr = malloc0(size); |
| if (!m->hdr) |
| return -ENOMEM; |
| |
| m->hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; |
| |
| type_get_type_system(genl_cmd_type, &type_system); |
| |
| r = type_system_get_type(type_system, &nl_type, cmd); |
| if (r < 0) |
| return r; |
| |
| m->hdr->nlmsg_len = size; |
| m->hdr->nlmsg_type = nlmsg_type; |
| |
| type_get_type_system(nl_type, &m->containers[0].type_system); |
| |
| *(struct genlmsghdr *) NLMSG_DATA(m->hdr) = (struct genlmsghdr) { |
| .cmd = cmd, |
| .version = genl_families[family].version, |
| }; |
| |
| *ret = TAKE_PTR(m); |
| |
| return 0; |
| } |
| |
| static int lookup_nlmsg_type(sd_netlink *nl, sd_genl_family_t family, uint16_t *ret) { |
| _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL; |
| uint16_t u; |
| void *v; |
| int r; |
| |
| assert(nl); |
| assert(nl->protocol == NETLINK_GENERIC); |
| assert(ret); |
| |
| if (family == SD_GENL_ID_CTRL) { |
| *ret = GENL_ID_CTRL; |
| return 0; |
| } |
| |
| v = hashmap_get(nl->genl_family_to_nlmsg_type, INT_TO_PTR(family)); |
| if (v) { |
| *ret = PTR_TO_UINT(v); |
| return 0; |
| } |
| |
| r = genl_message_new(nl, SD_GENL_ID_CTRL, GENL_ID_CTRL, CTRL_CMD_GETFAMILY, &req); |
| if (r < 0) |
| return r; |
| |
| r = sd_netlink_message_append_string(req, CTRL_ATTR_FAMILY_NAME, genl_families[family].name); |
| if (r < 0) |
| return r; |
| |
| r = sd_netlink_call(nl, req, 0, &reply); |
| if (r < 0) |
| return r; |
| |
| r = sd_netlink_message_read_u16(reply, CTRL_ATTR_FAMILY_ID, &u); |
| if (r < 0) |
| return r; |
| |
| r = hashmap_ensure_put(&nl->genl_family_to_nlmsg_type, NULL, INT_TO_PTR(family), UINT_TO_PTR(u)); |
| if (r < 0) |
| return r; |
| |
| r = hashmap_ensure_put(&nl->nlmsg_type_to_genl_family, NULL, UINT_TO_PTR(u), INT_TO_PTR(family)); |
| if (r < 0) |
| return r; |
| |
| *ret = u; |
| return 0; |
| } |
| |
| int sd_genl_message_new(sd_netlink *nl, sd_genl_family_t family, uint8_t cmd, sd_netlink_message **ret) { |
| uint16_t nlmsg_type = 0; /* Unnecessary initialization to appease gcc */ |
| int r; |
| |
| assert_return(nl, -EINVAL); |
| assert_return(nl->protocol == NETLINK_GENERIC, -EINVAL); |
| assert_return(ret, -EINVAL); |
| |
| r = lookup_nlmsg_type(nl, family, &nlmsg_type); |
| if (r < 0) |
| return r; |
| |
| return genl_message_new(nl, family, nlmsg_type, cmd, ret); |
| } |
| |
| int nlmsg_type_to_genl_family(const sd_netlink *nl, uint16_t nlmsg_type, sd_genl_family_t *ret) { |
| void *p; |
| |
| assert(nl); |
| assert(nl->protocol == NETLINK_GENERIC); |
| assert(ret); |
| |
| if (nlmsg_type == NLMSG_ERROR) |
| *ret = SD_GENL_ERROR; |
| else if (nlmsg_type == NLMSG_DONE) |
| *ret = SD_GENL_DONE; |
| else if (nlmsg_type == GENL_ID_CTRL) |
| *ret = SD_GENL_ID_CTRL; |
| else { |
| p = hashmap_get(nl->nlmsg_type_to_genl_family, UINT_TO_PTR(nlmsg_type)); |
| if (!p) |
| return -EOPNOTSUPP; |
| |
| *ret = PTR_TO_INT(p); |
| } |
| |
| return 0; |
| } |
| |
| int sd_genl_message_get_family(sd_netlink *nl, sd_netlink_message *m, sd_genl_family_t *ret) { |
| uint16_t nlmsg_type; |
| int r; |
| |
| assert_return(nl, -EINVAL); |
| assert_return(nl->protocol == NETLINK_GENERIC, -EINVAL); |
| assert_return(m, -EINVAL); |
| assert_return(ret, -EINVAL); |
| |
| r = sd_netlink_message_get_type(m, &nlmsg_type); |
| if (r < 0) |
| return r; |
| |
| return nlmsg_type_to_genl_family(nl, nlmsg_type, ret); |
| } |