1 #ifndef __BPF_SCM__ 2 #define __BPF_SCM__ 3 4 #include <sys/types.h> 5 #include <sys/socket.h> 6 7 #include "utils.h" 8 #include "bpf_elf.h" 9 10 #define BPF_SCM_AUX_VER 1 11 #define BPF_SCM_MAX_FDS ELF_MAX_MAPS 12 #define BPF_SCM_MSG_SIZE 1024 13 14 struct bpf_elf_st { 15 dev_t st_dev; 16 ino_t st_ino; 17 }; 18 19 struct bpf_map_aux { 20 unsigned short uds_ver; 21 unsigned short num_ent; 22 char obj_name[64]; 23 struct bpf_elf_st obj_st; 24 struct bpf_elf_map ent[BPF_SCM_MAX_FDS]; 25 }; 26 27 struct bpf_map_set_msg { 28 struct msghdr hdr; 29 struct iovec iov; 30 char msg_buf[BPF_SCM_MSG_SIZE]; 31 struct bpf_map_aux aux; 32 }; 33 34 static inline int *bpf_map_set_init(struct bpf_map_set_msg *msg, 35 struct sockaddr_un *addr, 36 unsigned int addr_len) 37 { 38 const unsigned int cmsg_ctl_len = sizeof(int) * BPF_SCM_MAX_FDS; 39 struct cmsghdr *cmsg; 40 41 msg->iov.iov_base = &msg->aux; 42 msg->iov.iov_len = sizeof(msg->aux); 43 44 msg->hdr.msg_iov = &msg->iov; 45 msg->hdr.msg_iovlen = 1; 46 47 msg->hdr.msg_name = (struct sockaddr *)addr; 48 msg->hdr.msg_namelen = addr_len; 49 50 BUILD_BUG_ON(sizeof(msg->msg_buf) < cmsg_ctl_len); 51 msg->hdr.msg_control = &msg->msg_buf; 52 msg->hdr.msg_controllen = cmsg_ctl_len; 53 54 cmsg = CMSG_FIRSTHDR(&msg->hdr); 55 cmsg->cmsg_len = msg->hdr.msg_controllen; 56 cmsg->cmsg_level = SOL_SOCKET; 57 cmsg->cmsg_type = SCM_RIGHTS; 58 59 return (int *)CMSG_DATA(cmsg); 60 } 61 62 static inline void bpf_map_set_init_single(struct bpf_map_set_msg *msg, 63 int num) 64 { 65 struct cmsghdr *cmsg; 66 67 msg->hdr.msg_controllen = CMSG_LEN(sizeof(int) * num); 68 msg->iov.iov_len = offsetof(struct bpf_map_aux, ent) + 69 sizeof(struct bpf_elf_map) * num; 70 71 cmsg = CMSG_FIRSTHDR(&msg->hdr); 72 cmsg->cmsg_len = msg->hdr.msg_controllen; 73 } 74 75 #endif /* __BPF_SCM__ */ 76
