| /* |
| * m_bpf.c BPF based action module |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * Authors: Jiri Pirko <jiri@resnulli.us> |
| * Daniel Borkmann <daniel@iogearbox.net> |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <stdbool.h> |
| #include <libgen.h> |
| #include <linux/bpf.h> |
| #include <linux/tc_act/tc_bpf.h> |
| |
| #include "utils.h" |
| #include "rt_names.h" |
| #include "tc_util.h" |
| #include "tc_bpf.h" |
| |
| static const enum bpf_prog_type bpf_type = BPF_PROG_TYPE_SCHED_ACT; |
| |
| static void explain(void) |
| { |
| fprintf(stderr, "Usage: ... bpf ... [ index INDEX ]\n"); |
| fprintf(stderr, "\n"); |
| fprintf(stderr, "BPF use case:\n"); |
| fprintf(stderr, " bytecode BPF_BYTECODE\n"); |
| fprintf(stderr, " bytecode-file FILE\n"); |
| fprintf(stderr, "\n"); |
| fprintf(stderr, "eBPF use case:\n"); |
| fprintf(stderr, " object-file FILE [ section ACT_NAME ] [ export UDS_FILE ]"); |
| fprintf(stderr, " [ verbose ]\n"); |
| fprintf(stderr, "\n"); |
| fprintf(stderr, "Where BPF_BYTECODE := \'s,c t f k,c t f k,c t f k,...\'\n"); |
| fprintf(stderr, "c,t,f,k and s are decimals; s denotes number of 4-tuples\n"); |
| fprintf(stderr, "\n"); |
| fprintf(stderr, "Where FILE points to a file containing the BPF_BYTECODE string,\n"); |
| fprintf(stderr, "an ELF file containing eBPF map definitions and bytecode.\n"); |
| fprintf(stderr, "\n"); |
| fprintf(stderr, "Where ACT_NAME refers to the section name containing the\n"); |
| fprintf(stderr, "action (default \'%s\').\n", bpf_default_section(bpf_type)); |
| fprintf(stderr, "\n"); |
| fprintf(stderr, "Where UDS_FILE points to a unix domain socket file in order\n"); |
| fprintf(stderr, "to hand off control of all created eBPF maps to an agent.\n"); |
| fprintf(stderr, "\n"); |
| fprintf(stderr, "Where optionally INDEX points to an existing action, or\n"); |
| fprintf(stderr, "explicitly specifies an action index upon creation.\n"); |
| } |
| |
| static void usage(void) |
| { |
| explain(); |
| exit(-1); |
| } |
| |
| static int parse_bpf(struct action_util *a, int *argc_p, char ***argv_p, |
| int tca_id, struct nlmsghdr *n) |
| { |
| char **argv = *argv_p, bpf_name[256]; |
| struct rtattr *tail; |
| struct tc_act_bpf parm = { 0 }; |
| struct sock_filter bpf_ops[BPF_MAXINSNS]; |
| bool ebpf_fill = false, bpf_fill = false; |
| bool ebpf = false, seen_run = false; |
| const char *bpf_uds_name = NULL; |
| const char *bpf_sec_name = NULL; |
| char *bpf_obj = NULL; |
| int argc = *argc_p, ret = 0; |
| __u16 bpf_len = 0; |
| __u32 bpf_fd = 0; |
| |
| if (matches(*argv, "bpf") != 0) |
| return -1; |
| |
| NEXT_ARG(); |
| |
| while (argc > 0) { |
| if (matches(*argv, "run") == 0) { |
| bool from_file, bpf_verbose; |
| int ret; |
| |
| NEXT_ARG(); |
| opt_bpf: |
| bpf_sec_name = bpf_default_section(bpf_type); |
| bpf_verbose = false; |
| seen_run = true; |
| |
| if (strcmp(*argv, "bytecode-file") == 0 || |
| strcmp(*argv, "bcf") == 0) { |
| from_file = true; |
| } else if (strcmp(*argv, "bytecode") == 0 || |
| strcmp(*argv, "bc") == 0) { |
| from_file = false; |
| } else if (strcmp(*argv, "object-file") == 0 || |
| strcmp(*argv, "obj") == 0) { |
| ebpf = true; |
| } else { |
| fprintf(stderr, "unexpected \"%s\"\n", *argv); |
| explain(); |
| return -1; |
| } |
| |
| NEXT_ARG(); |
| if (ebpf) { |
| bpf_uds_name = getenv(BPF_ENV_UDS); |
| bpf_obj = *argv; |
| |
| NEXT_ARG_FWD(); |
| |
| if (argc > 0 && |
| (strcmp(*argv, "section") == 0 || |
| strcmp(*argv, "sec") == 0)) { |
| NEXT_ARG(); |
| bpf_sec_name = *argv; |
| NEXT_ARG_FWD(); |
| } |
| if (argc > 0 && !bpf_uds_name && |
| (strcmp(*argv, "export") == 0 || |
| strcmp(*argv, "exp") == 0)) { |
| NEXT_ARG(); |
| bpf_uds_name = *argv; |
| NEXT_ARG_FWD(); |
| } |
| if (argc > 0 && |
| (strcmp(*argv, "verbose") == 0 || |
| strcmp(*argv, "verb") == 0)) { |
| bpf_verbose = true; |
| NEXT_ARG_FWD(); |
| } |
| |
| PREV_ARG(); |
| } |
| |
| ret = ebpf ? bpf_open_object(bpf_obj, bpf_type, bpf_sec_name, |
| bpf_verbose) : |
| bpf_parse_ops(argc, argv, bpf_ops, from_file); |
| if (ret < 0) { |
| fprintf(stderr, "%s\n", ebpf ? |
| "Could not load object" : |
| "Illegal \"bytecode\""); |
| return -1; |
| } |
| |
| if (ebpf) { |
| bpf_obj = basename(bpf_obj); |
| |
| snprintf(bpf_name, sizeof(bpf_name), "%s:[%s]", |
| bpf_obj, bpf_sec_name); |
| |
| bpf_fd = ret; |
| ebpf_fill = true; |
| } else { |
| bpf_len = ret; |
| bpf_fill = true; |
| } |
| } else if (matches(*argv, "help") == 0) { |
| usage(); |
| } else if (matches(*argv, "index") == 0) { |
| break; |
| } else { |
| if (!seen_run) |
| goto opt_bpf; |
| break; |
| } |
| |
| NEXT_ARG_FWD(); |
| } |
| |
| parm.action = TC_ACT_PIPE; |
| if (argc) { |
| if (matches(*argv, "reclassify") == 0) { |
| parm.action = TC_ACT_RECLASSIFY; |
| NEXT_ARG_FWD(); |
| } else if (matches(*argv, "pipe") == 0) { |
| parm.action = TC_ACT_PIPE; |
| NEXT_ARG_FWD(); |
| } else if (matches(*argv, "drop") == 0 || |
| matches(*argv, "shot") == 0) { |
| parm.action = TC_ACT_SHOT; |
| NEXT_ARG_FWD(); |
| } else if (matches(*argv, "continue") == 0) { |
| parm.action = TC_ACT_UNSPEC; |
| NEXT_ARG_FWD(); |
| } else if (matches(*argv, "pass") == 0 || |
| matches(*argv, "ok") == 0) { |
| parm.action = TC_ACT_OK; |
| NEXT_ARG_FWD(); |
| } |
| } |
| |
| if (argc) { |
| if (matches(*argv, "index") == 0) { |
| NEXT_ARG(); |
| if (get_u32(&parm.index, *argv, 10)) { |
| fprintf(stderr, "bpf: Illegal \"index\"\n"); |
| return -1; |
| } |
| |
| NEXT_ARG_FWD(); |
| } |
| } |
| |
| tail = NLMSG_TAIL(n); |
| |
| addattr_l(n, MAX_MSG, tca_id, NULL, 0); |
| addattr_l(n, MAX_MSG, TCA_ACT_BPF_PARMS, &parm, sizeof(parm)); |
| |
| if (ebpf_fill) { |
| addattr32(n, MAX_MSG, TCA_ACT_BPF_FD, bpf_fd); |
| addattrstrz(n, MAX_MSG, TCA_ACT_BPF_NAME, bpf_name); |
| } else if (bpf_fill) { |
| addattr16(n, MAX_MSG, TCA_ACT_BPF_OPS_LEN, bpf_len); |
| addattr_l(n, MAX_MSG, TCA_ACT_BPF_OPS, &bpf_ops, |
| bpf_len * sizeof(struct sock_filter)); |
| } |
| |
| tail->rta_len = (char *)NLMSG_TAIL(n) - (char *)tail; |
| |
| *argc_p = argc; |
| *argv_p = argv; |
| |
| if (bpf_uds_name) |
| ret = bpf_send_map_fds(bpf_uds_name, bpf_obj); |
| |
| return ret; |
| } |
| |
| static int print_bpf(struct action_util *au, FILE *f, struct rtattr *arg) |
| { |
| struct rtattr *tb[TCA_ACT_BPF_MAX + 1]; |
| struct tc_act_bpf *parm; |
| SPRINT_BUF(action_buf); |
| |
| if (arg == NULL) |
| return -1; |
| |
| parse_rtattr_nested(tb, TCA_ACT_BPF_MAX, arg); |
| |
| if (!tb[TCA_ACT_BPF_PARMS]) { |
| fprintf(f, "[NULL bpf parameters]"); |
| return -1; |
| } |
| |
| parm = RTA_DATA(tb[TCA_ACT_BPF_PARMS]); |
| |
| fprintf(f, "bpf "); |
| |
| if (tb[TCA_ACT_BPF_NAME]) |
| fprintf(f, "%s ", rta_getattr_str(tb[TCA_ACT_BPF_NAME])); |
| else if (tb[TCA_ACT_BPF_FD]) |
| fprintf(f, "pfd %u ", rta_getattr_u32(tb[TCA_ACT_BPF_FD])); |
| |
| if (tb[TCA_ACT_BPF_OPS] && tb[TCA_ACT_BPF_OPS_LEN]) { |
| bpf_print_ops(f, tb[TCA_ACT_BPF_OPS], |
| rta_getattr_u16(tb[TCA_ACT_BPF_OPS_LEN])); |
| fprintf(f, " "); |
| } |
| |
| fprintf(f, "default-action %s\n", action_n2a(parm->action, action_buf, |
| sizeof(action_buf))); |
| fprintf(f, "\tindex %d ref %d bind %d", parm->index, parm->refcnt, |
| parm->bindcnt); |
| |
| if (show_stats) { |
| if (tb[TCA_ACT_BPF_TM]) { |
| struct tcf_t *tm = RTA_DATA(tb[TCA_ACT_BPF_TM]); |
| print_tm(f, tm); |
| } |
| } |
| |
| fprintf(f, "\n "); |
| |
| return 0; |
| } |
| |
| struct action_util bpf_action_util = { |
| .id = "bpf", |
| .parse_aopt = parse_bpf, |
| .print_aopt = print_bpf, |
| }; |