1 #ifndef __BPF_SCM__ 2 #define __BPF_SCM__ 3 4 #include <sys/types.h> 5 #include <sys/socket.h> 6 #include <sys/un.h> 7 8 #include "utils.h" 9 #include "bpf_elf.h" 10 11 #define BPF_SCM_AUX_VER 1 12 #define BPF_SCM_MAX_FDS ELF_MAX_MAPS 13 #define BPF_SCM_MSG_SIZE 1024 14 15 struct bpf_elf_st { 16 dev_t st_dev; 17 ino_t st_ino; 18 }; 19 20 struct bpf_map_aux { 21 unsigned short uds_ver; 22 unsigned short num_ent; 23 char obj_name[64]; 24 struct bpf_elf_st obj_st; 25 struct bpf_elf_map ent[BPF_SCM_MAX_FDS]; 26 }; 27 28 struct bpf_map_set_msg { 29 struct msghdr hdr; 30 struct iovec iov; 31 char msg_buf[BPF_SCM_MSG_SIZE]; 32 struct bpf_map_aux aux; 33 }; 34 35 static inline int *bpf_map_set_init(struct bpf_map_set_msg *msg, 36 struct sockaddr_un *addr, 37 unsigned int addr_len) 38 { 39 const unsigned int cmsg_ctl_len = sizeof(int) * BPF_SCM_MAX_FDS; 40 struct cmsghdr *cmsg; 41 42 msg->iov.iov_base = &msg->aux; 43 msg->iov.iov_len = sizeof(msg->aux); 44 45 msg->hdr.msg_iov = &msg->iov; 46 msg->hdr.msg_iovlen = 1; 47 48 msg->hdr.msg_name = (struct sockaddr *)addr; 49 msg->hdr.msg_namelen = addr_len; 50 51 BUILD_BUG_ON(sizeof(msg->msg_buf) < cmsg_ctl_len); 52 msg->hdr.msg_control = &msg->msg_buf; 53 msg->hdr.msg_controllen = cmsg_ctl_len; 54 55 cmsg = CMSG_FIRSTHDR(&msg->hdr); 56 cmsg->cmsg_len = msg->hdr.msg_controllen; 57 cmsg->cmsg_level = SOL_SOCKET; 58 cmsg->cmsg_type = SCM_RIGHTS; 59 60 return (int *)CMSG_DATA(cmsg); 61 } 62 63 static inline void bpf_map_set_init_single(struct bpf_map_set_msg *msg, 64 int num) 65 { 66 struct cmsghdr *cmsg; 67 68 msg->hdr.msg_controllen = CMSG_LEN(sizeof(int) * num); 69 msg->iov.iov_len = offsetof(struct bpf_map_aux, ent) + 70 sizeof(struct bpf_elf_map) * num; 71 72 cmsg = CMSG_FIRSTHDR(&msg->hdr); 73 cmsg->cmsg_len = msg->hdr.msg_controllen; 74 } 75 76 #endif /* __BPF_SCM__ */ 77
