ebpf/ebpf.c

   1 /*
   2  * QEMU eBPF binary declaration routine.
   3  *
   4  * Developed by Daynix Computing LTD (http://www.daynix.com)
   5  *
   6  * Authors:
   7  *  Andrew Melnychenko <andrew@daynix.com>
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12 #include "qemu/osdep.h"
  13 #include "qemu/queue.h"
  14 #include "qapi/error.h"
  15 #include "qapi/qapi-commands-ebpf.h"
  16 #include "ebpf/ebpf.h"
  17
  18 typedef struct ElfBinaryDataEntry {
  19     int id;
  20     const void *data;
  21     size_t datalen;
  22
  23     QSLIST_ENTRY(ElfBinaryDataEntry) node;
  24 } ElfBinaryDataEntry;
  25
  26 static QSLIST_HEAD(, ElfBinaryDataEntry) ebpf_elf_obj_list =
  27                                             QSLIST_HEAD_INITIALIZER();
  28
  29 void ebpf_register_binary_data(int id, const void *data, size_t datalen)
  30 {
  31     struct ElfBinaryDataEntry *dataentry = NULL;
  32
  33     dataentry = g_new0(struct ElfBinaryDataEntry, 1);
  34     dataentry->data = data;
  35     dataentry->datalen = datalen;
  36     dataentry->id = id;
  37
  38     QSLIST_INSERT_HEAD(&ebpf_elf_obj_list, dataentry, node);
  39 }
  40
  41 const void *ebpf_find_binary_by_id(int id, size_t *sz, Error **errp)
  42 {
  43     struct ElfBinaryDataEntry *it = NULL;
  44     QSLIST_FOREACH(it, &ebpf_elf_obj_list, node) {
  45         if (id == it->id) {
  46             *sz = it->datalen;
  47             return it->data;
  48         }
  49     }
  50
  51     error_setg(errp, "can't find eBPF object with id: %d", id);
  52
  53     return NULL;
  54 }
  55
  56 EbpfObject *qmp_request_ebpf(EbpfProgramID id, Error **errp)
  57 {
  58     EbpfObject *ret = NULL;
  59     size_t size = 0;
  60     const void *data = ebpf_find_binary_by_id(id, &size, errp);
  61     if (!data) {
  62         return NULL;
  63     }
  64
  65     ret = g_new0(EbpfObject, 1);
  66     ret->object = g_base64_encode(data, size);
  67
  68     return ret;
  69 }