1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * System call table mapper
4  *
5  * (C) 2016 Arnaldo Carvalho de Melo <acme@redhat.com>
6  */
7 
8 #include "syscalltbl.h"
9 #include <stdlib.h>
10 #include <linux/compiler.h>
11 #include <linux/zalloc.h>
12 
13 #ifdef HAVE_SYSCALL_TABLE_SUPPORT
14 #include <string.h>
15 #include "string2.h"
16 
17 #if defined(__x86_64__)
18 #include <asm/syscalls_64.c>
19 const int syscalltbl_native_max_id = SYSCALLTBL_x86_64_MAX_ID;
20 static const char *const *syscalltbl_native = syscalltbl_x86_64;
21 #elif defined(__i386__)
22 #include <asm/syscalls_32.c>
23 const int syscalltbl_native_max_id = SYSCALLTBL_x86_MAX_ID;
24 static const char *const *syscalltbl_native = syscalltbl_x86;
25 #elif defined(__s390x__)
26 #include <asm/syscalls_64.c>
27 const int syscalltbl_native_max_id = SYSCALLTBL_S390_64_MAX_ID;
28 static const char *const *syscalltbl_native = syscalltbl_s390_64;
29 #elif defined(__powerpc64__)
30 #include <asm/syscalls_64.c>
31 const int syscalltbl_native_max_id = SYSCALLTBL_POWERPC_64_MAX_ID;
32 static const char *const *syscalltbl_native = syscalltbl_powerpc_64;
33 #elif defined(__powerpc__)
34 #include <asm/syscalls_32.c>
35 const int syscalltbl_native_max_id = SYSCALLTBL_POWERPC_32_MAX_ID;
36 static const char *const *syscalltbl_native = syscalltbl_powerpc_32;
37 #elif defined(__aarch64__)
38 #include <asm/syscalls.c>
39 const int syscalltbl_native_max_id = SYSCALLTBL_ARM64_MAX_ID;
40 static const char *const *syscalltbl_native = syscalltbl_arm64;
41 #elif defined(__mips__)
42 #include <asm/syscalls_n64.c>
43 const int syscalltbl_native_max_id = SYSCALLTBL_MIPS_N64_MAX_ID;
44 static const char *const *syscalltbl_native = syscalltbl_mips_n64;
45 #elif defined(__loongarch__)
46 #include <asm/syscalls.c>
47 const int syscalltbl_native_max_id = SYSCALLTBL_LOONGARCH_MAX_ID;
48 static const char *const *syscalltbl_native = syscalltbl_loongarch;
49 #else
50 const int syscalltbl_native_max_id = 0;
51 static const char *const syscalltbl_native[] = {
52 	[0] = "unknown",
53 };
54 #endif
55 
56 struct syscall {
57 	int id;
58 	const char *name;
59 };
60 
syscallcmpname(const void * vkey,const void * ventry)61 static int syscallcmpname(const void *vkey, const void *ventry)
62 {
63 	const char *key = vkey;
64 	const struct syscall *entry = ventry;
65 
66 	return strcmp(key, entry->name);
67 }
68 
syscallcmp(const void * va,const void * vb)69 static int syscallcmp(const void *va, const void *vb)
70 {
71 	const struct syscall *a = va, *b = vb;
72 
73 	return strcmp(a->name, b->name);
74 }
75 
syscalltbl__init_native(struct syscalltbl * tbl)76 static int syscalltbl__init_native(struct syscalltbl *tbl)
77 {
78 	int nr_entries = 0, i, j;
79 	struct syscall *entries;
80 
81 	for (i = 0; i <= syscalltbl_native_max_id; ++i)
82 		if (syscalltbl_native[i])
83 			++nr_entries;
84 
85 	entries = tbl->syscalls.entries = malloc(sizeof(struct syscall) * nr_entries);
86 	if (tbl->syscalls.entries == NULL)
87 		return -1;
88 
89 	for (i = 0, j = 0; i <= syscalltbl_native_max_id; ++i) {
90 		if (syscalltbl_native[i]) {
91 			entries[j].name = syscalltbl_native[i];
92 			entries[j].id = i;
93 			++j;
94 		}
95 	}
96 
97 	qsort(tbl->syscalls.entries, nr_entries, sizeof(struct syscall), syscallcmp);
98 	tbl->syscalls.nr_entries = nr_entries;
99 	tbl->syscalls.max_id	 = syscalltbl_native_max_id;
100 	return 0;
101 }
102 
syscalltbl__new(void)103 struct syscalltbl *syscalltbl__new(void)
104 {
105 	struct syscalltbl *tbl = malloc(sizeof(*tbl));
106 	if (tbl) {
107 		if (syscalltbl__init_native(tbl)) {
108 			free(tbl);
109 			return NULL;
110 		}
111 	}
112 	return tbl;
113 }
114 
syscalltbl__delete(struct syscalltbl * tbl)115 void syscalltbl__delete(struct syscalltbl *tbl)
116 {
117 	zfree(&tbl->syscalls.entries);
118 	free(tbl);
119 }
120 
syscalltbl__name(const struct syscalltbl * tbl __maybe_unused,int id)121 const char *syscalltbl__name(const struct syscalltbl *tbl __maybe_unused, int id)
122 {
123 	return id <= syscalltbl_native_max_id ? syscalltbl_native[id]: NULL;
124 }
125 
syscalltbl__id(struct syscalltbl * tbl,const char * name)126 int syscalltbl__id(struct syscalltbl *tbl, const char *name)
127 {
128 	struct syscall *sc = bsearch(name, tbl->syscalls.entries,
129 				     tbl->syscalls.nr_entries, sizeof(*sc),
130 				     syscallcmpname);
131 
132 	return sc ? sc->id : -1;
133 }
134 
syscalltbl__id_at_idx(struct syscalltbl * tbl,int idx)135 int syscalltbl__id_at_idx(struct syscalltbl *tbl, int idx)
136 {
137 	struct syscall *syscalls = tbl->syscalls.entries;
138 
139 	return idx < tbl->syscalls.nr_entries ? syscalls[idx].id : -1;
140 }
141 
syscalltbl__strglobmatch_next(struct syscalltbl * tbl,const char * syscall_glob,int * idx)142 int syscalltbl__strglobmatch_next(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
143 {
144 	int i;
145 	struct syscall *syscalls = tbl->syscalls.entries;
146 
147 	for (i = *idx + 1; i < tbl->syscalls.nr_entries; ++i) {
148 		if (strglobmatch(syscalls[i].name, syscall_glob)) {
149 			*idx = i;
150 			return syscalls[i].id;
151 		}
152 	}
153 
154 	return -1;
155 }
156 
syscalltbl__strglobmatch_first(struct syscalltbl * tbl,const char * syscall_glob,int * idx)157 int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
158 {
159 	*idx = -1;
160 	return syscalltbl__strglobmatch_next(tbl, syscall_glob, idx);
161 }
162 
163 #else /* HAVE_SYSCALL_TABLE_SUPPORT */
164 
165 #include <libaudit.h>
166 
syscalltbl__new(void)167 struct syscalltbl *syscalltbl__new(void)
168 {
169 	struct syscalltbl *tbl = zalloc(sizeof(*tbl));
170 	if (tbl)
171 		tbl->audit_machine = audit_detect_machine();
172 	return tbl;
173 }
174 
syscalltbl__delete(struct syscalltbl * tbl)175 void syscalltbl__delete(struct syscalltbl *tbl)
176 {
177 	free(tbl);
178 }
179 
syscalltbl__name(const struct syscalltbl * tbl,int id)180 const char *syscalltbl__name(const struct syscalltbl *tbl, int id)
181 {
182 	return audit_syscall_to_name(id, tbl->audit_machine);
183 }
184 
syscalltbl__id(struct syscalltbl * tbl,const char * name)185 int syscalltbl__id(struct syscalltbl *tbl, const char *name)
186 {
187 	return audit_name_to_syscall(name, tbl->audit_machine);
188 }
189 
syscalltbl__id_at_idx(struct syscalltbl * tbl __maybe_unused,int idx)190 int syscalltbl__id_at_idx(struct syscalltbl *tbl __maybe_unused, int idx)
191 {
192 	return idx;
193 }
194 
syscalltbl__strglobmatch_next(struct syscalltbl * tbl __maybe_unused,const char * syscall_glob __maybe_unused,int * idx __maybe_unused)195 int syscalltbl__strglobmatch_next(struct syscalltbl *tbl __maybe_unused,
196 				  const char *syscall_glob __maybe_unused, int *idx __maybe_unused)
197 {
198 	return -1;
199 }
200 
syscalltbl__strglobmatch_first(struct syscalltbl * tbl,const char * syscall_glob,int * idx)201 int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
202 {
203 	return syscalltbl__strglobmatch_next(tbl, syscall_glob, idx);
204 }
205 #endif /* HAVE_SYSCALL_TABLE_SUPPORT */
206