| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <time.h> |
| |
| #include <libmnl/libmnl.h> |
| #include <linux/genetlink.h> |
| |
| #include <libgtpnl/gtpnl.h> |
| |
| #include "internal.h" |
| |
| struct nlmsghdr * |
| genl_nlmsg_build_hdr(char *buf, uint16_t type, uint16_t flags, uint32_t seq, |
| uint8_t cmd) |
| { |
| struct nlmsghdr *nlh; |
| struct genlmsghdr *genl; |
| |
| nlh = mnl_nlmsg_put_header(buf); |
| nlh->nlmsg_type = type; |
| nlh->nlmsg_flags = NLM_F_REQUEST | flags; |
| nlh->nlmsg_seq = seq; |
| |
| genl = mnl_nlmsg_put_extra_header(nlh, sizeof(struct genlmsghdr)); |
| genl->cmd = cmd; |
| genl->version = 0; |
| |
| return nlh; |
| } |
| EXPORT_SYMBOL(genl_nlmsg_build_hdr); |
| |
| static int genl_ctrl_validate_cb(const struct nlattr *attr, void *data) |
| { |
| const struct nlattr **tb = data; |
| int type = mnl_attr_get_type(attr); |
| |
| if (mnl_attr_type_valid(attr, CTRL_ATTR_MAX) < 0) |
| return MNL_CB_OK; |
| |
| switch(type) { |
| case CTRL_ATTR_FAMILY_ID: |
| if (mnl_attr_validate(attr, MNL_TYPE_U16) < 0) { |
| perror("mnl_attr_validate"); |
| return MNL_CB_ERROR; |
| } |
| break; |
| } |
| tb[type] = attr; |
| return MNL_CB_OK; |
| } |
| |
| static int genl_ctrl_cb(const struct nlmsghdr *nlh, void *data) |
| { |
| struct nlattr *tb[CTRL_ATTR_MAX + 1] = {}; |
| struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh); |
| int32_t *genl_id = data; |
| |
| mnl_attr_parse(nlh, sizeof(*genl), genl_ctrl_validate_cb, tb); |
| if (tb[CTRL_ATTR_FAMILY_ID]) |
| *genl_id = mnl_attr_get_u16(tb[CTRL_ATTR_FAMILY_ID]); |
| else |
| *genl_id = -1; |
| |
| return MNL_CB_OK; |
| } |
| |
| struct mnl_socket *genl_socket_open(void) |
| { |
| struct mnl_socket *nl; |
| |
| nl = mnl_socket_open(NETLINK_GENERIC); |
| if (nl == NULL) { |
| perror("mnl_socket_open"); |
| return NULL; |
| } |
| |
| if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) { |
| perror("mnl_socket_bind"); |
| return NULL; |
| } |
| |
| return nl; |
| } |
| EXPORT_SYMBOL(genl_socket_open); |
| |
| int genl_socket_talk(struct mnl_socket *nl, struct nlmsghdr *nlh, uint32_t seq, |
| int (*cb)(const struct nlmsghdr *nlh, void *data), |
| void *data) |
| { |
| char buf[MNL_SOCKET_BUFFER_SIZE]; |
| int ret; |
| |
| if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) { |
| perror("mnl_socket_send"); |
| return -1; |
| } |
| |
| ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); |
| while (ret > 0) { |
| ret = mnl_cb_run(buf, ret, seq, mnl_socket_get_portid(nl), |
| cb, data); |
| if (ret <= 0) |
| break; |
| ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); |
| } |
| |
| return ret; |
| } |
| EXPORT_SYMBOL(genl_socket_talk); |
| |
| static struct nlmsghdr * |
| genl_nlmsg_build_lookup(char *buf, const char *subsys_name) |
| { |
| struct nlmsghdr *nlh; |
| struct genlmsghdr *genl; |
| |
| nlh = mnl_nlmsg_put_header(buf); |
| nlh->nlmsg_type = GENL_ID_CTRL; |
| nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; |
| nlh->nlmsg_seq = time(NULL); |
| |
| genl = mnl_nlmsg_put_extra_header(nlh, sizeof(struct genlmsghdr)); |
| genl->cmd = CTRL_CMD_GETFAMILY; |
| genl->version = 1; |
| |
| mnl_attr_put_u32(nlh, CTRL_ATTR_FAMILY_ID, GENL_ID_CTRL); |
| mnl_attr_put_strz(nlh, CTRL_ATTR_FAMILY_NAME, subsys_name); |
| |
| return nlh; |
| } |
| |
| int genl_lookup_family(struct mnl_socket *nl, const char *family) |
| { |
| int32_t genl_id; |
| char buf[MNL_SOCKET_BUFFER_SIZE]; |
| struct nlmsghdr *nlh = genl_nlmsg_build_lookup(buf, "gtp"); |
| int err; |
| |
| err = genl_socket_talk(nl, nlh, nlh->nlmsg_seq, genl_ctrl_cb, &genl_id); |
| if (err < 0) |
| return -1; |
| |
| return genl_id; |
| } |
| EXPORT_SYMBOL(genl_lookup_family); |