1/*
  2 * System call table mapper
  3 *
  4 * (C) 2016 Arnaldo Carvalho de Melo <acme@redhat.com>
  5 *
  6 * This program is free software; you can redistribute it and/or modify it
  7 * under the terms and conditions of the GNU General Public License,
  8 * version 2, as published by the Free Software Foundation.
  9 *
 10 * This program is distributed in the hope it will be useful, but WITHOUT
 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 13 * more details.
 14 */
 15
 16#include "syscalltbl.h"
 17#include <stdlib.h>
 18
 19#ifdef HAVE_SYSCALL_TABLE
 20#include <linux/compiler.h>
 21#include <string.h>
 22#include "util.h"
 23
 24#if defined(__x86_64__)
 25#include <asm/syscalls_64.c>
 26const int syscalltbl_native_max_id = SYSCALLTBL_x86_64_MAX_ID;
 27static const char **syscalltbl_native = syscalltbl_x86_64;
 28#endif
 29
 30struct syscall {
 31	int id;
 32	const char *name;
 33};
 34
 35static int syscallcmpname(const void *vkey, const void *ventry)
 36{
 37	const char *key = vkey;
 38	const struct syscall *entry = ventry;
 39
 40	return strcmp(key, entry->name);
 41}
 42
 43static int syscallcmp(const void *va, const void *vb)
 44{
 45	const struct syscall *a = va, *b = vb;
 46
 47	return strcmp(a->name, b->name);
 48}
 49
 50static int syscalltbl__init_native(struct syscalltbl *tbl)
 51{
 52	int nr_entries = 0, i, j;
 53	struct syscall *entries;
 54
 55	for (i = 0; i <= syscalltbl_native_max_id; ++i)
 56		if (syscalltbl_native[i])
 57			++nr_entries;
 58
 59	entries = tbl->syscalls.entries = malloc(sizeof(struct syscall) * nr_entries);
 60	if (tbl->syscalls.entries == NULL)
 61		return -1;
 62
 63	for (i = 0, j = 0; i <= syscalltbl_native_max_id; ++i) {
 64		if (syscalltbl_native[i]) {
 65			entries[j].name = syscalltbl_native[i];
 66			entries[j].id = i;
 67			++j;
 68		}
 69	}
 70
 71	qsort(tbl->syscalls.entries, nr_entries, sizeof(struct syscall), syscallcmp);
 72	tbl->syscalls.nr_entries = nr_entries;
 73	return 0;
 74}
 75
 76struct syscalltbl *syscalltbl__new(void)
 77{
 78	struct syscalltbl *tbl = malloc(sizeof(*tbl));
 79	if (tbl) {
 80		if (syscalltbl__init_native(tbl)) {
 81			free(tbl);
 82			return NULL;
 83		}
 84	}
 85	return tbl;
 86}
 87
 88void syscalltbl__delete(struct syscalltbl *tbl)
 89{
 90	zfree(&tbl->syscalls.entries);
 91	free(tbl);
 92}
 93
 94const char *syscalltbl__name(const struct syscalltbl *tbl __maybe_unused, int id)
 95{
 96	return id <= syscalltbl_native_max_id ? syscalltbl_native[id]: NULL;
 97}
 98
 99int syscalltbl__id(struct syscalltbl *tbl, const char *name)
100{
101	struct syscall *sc = bsearch(name, tbl->syscalls.entries,
102				     tbl->syscalls.nr_entries, sizeof(*sc),
103				     syscallcmpname);
104
105	return sc ? sc->id : -1;
106}
107
108#else /* HAVE_SYSCALL_TABLE */
109
110#include <libaudit.h>
111
112struct syscalltbl *syscalltbl__new(void)
113{
114	struct syscalltbl *tbl = malloc(sizeof(*tbl));
115	if (tbl)
116		tbl->audit_machine = audit_detect_machine();
117	return tbl;
118}
119
120void syscalltbl__delete(struct syscalltbl *tbl)
121{
122	free(tbl);
123}
124
125const char *syscalltbl__name(const struct syscalltbl *tbl, int id)
126{
127	return audit_syscall_to_name(id, tbl->audit_machine);
128}
129
130int syscalltbl__id(struct syscalltbl *tbl, const char *name)
131{
132	return audit_name_to_syscall(name, tbl->audit_machine);
133}
134#endif /* HAVE_SYSCALL_TABLE */