1 /*-
2 * Copyright (c) 2019 Leandro Lupori
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 *
10 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
11 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
12 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
13 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
14 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
15 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
16 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
18 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
19 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
20 * SUCH DAMAGE.
21 */
22
23 static uint32_t cpu_features;
24 static uint32_t cpu_features2;
25
26 static void
ifunc_init(const Elf_Auxinfo * aux)27 ifunc_init(const Elf_Auxinfo *aux)
28 {
29 /* Digest the auxiliary vector. */
30 for (; aux->a_type != AT_NULL; aux++) {
31 switch (aux->a_type) {
32 case AT_HWCAP:
33 cpu_features = (uint32_t)aux->a_un.a_val;
34 break;
35 case AT_HWCAP2:
36 cpu_features2 = (uint32_t)aux->a_un.a_val;
37 break;
38 }
39 }
40 }
41
42 static void
crt1_handle_rela(const Elf_Rela * r)43 crt1_handle_rela(const Elf_Rela *r)
44 {
45 typedef Elf_Addr (*ifunc_resolver_t)(
46 uint32_t, uint32_t, uint64_t, uint64_t,
47 uint64_t, uint64_t, uint64_t, uint64_t);
48 Elf_Addr *ptr, *where, target;
49
50 switch (ELF_R_TYPE(r->r_info)) {
51 case R_PPC_IRELATIVE:
52 ptr = (Elf_Addr *)r->r_addend;
53 where = (Elf_Addr *)r->r_offset;
54 target = ((ifunc_resolver_t)ptr)(cpu_features, cpu_features2,
55 0, 0, 0, 0, 0, 0);
56 *where = target;
57 break;
58 }
59 }
60