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51#include <inttypes.h>
52#include <stdint.h>
53#include <unistd.h>
54#include <stdarg.h>
55#include <stdlib.h>
56#include <stdio.h>
57#include <string.h>
58#include <fcntl.h>
59#include <err.h>
60
61#include <sys/mman.h>
62#include <sys/types.h>
63
64#include <tools/le_byteshift.h>
65
66#include <linux/elf.h>
67#include <linux/types.h>
68
69const char *outfilename;
70
71
72enum {
73 sym_vvar_start,
74 sym_vvar_page,
75 sym_hpet_page,
76 sym_pvclock_page,
77 sym_hvclock_page,
78 sym_VDSO_FAKE_SECTION_TABLE_START,
79 sym_VDSO_FAKE_SECTION_TABLE_END,
80};
81
82const int special_pages[] = {
83 sym_vvar_page,
84 sym_hpet_page,
85 sym_pvclock_page,
86 sym_hvclock_page,
87};
88
89struct vdso_sym {
90 const char *name;
91 bool export;
92};
93
94struct vdso_sym required_syms[] = {
95 [sym_vvar_start] = {"vvar_start", true},
96 [sym_vvar_page] = {"vvar_page", true},
97 [sym_hpet_page] = {"hpet_page", true},
98 [sym_pvclock_page] = {"pvclock_page", true},
99 [sym_hvclock_page] = {"hvclock_page", true},
100 [sym_VDSO_FAKE_SECTION_TABLE_START] = {
101 "VDSO_FAKE_SECTION_TABLE_START", false
102 },
103 [sym_VDSO_FAKE_SECTION_TABLE_END] = {
104 "VDSO_FAKE_SECTION_TABLE_END", false
105 },
106 {"VDSO32_NOTE_MASK", true},
107 {"__kernel_vsyscall", true},
108 {"__kernel_sigreturn", true},
109 {"__kernel_rt_sigreturn", true},
110 {"int80_landing_pad", true},
111};
112
113__attribute__((format(printf, 1, 2))) __attribute__((noreturn))
114static void fail(const char *format, ...)
115{
116 va_list ap;
117 va_start(ap, format);
118 fprintf(stderr, "Error: ");
119 vfprintf(stderr, format, ap);
120 if (outfilename)
121 unlink(outfilename);
122 exit(1);
123 va_end(ap);
124}
125
126
127
128
129#define GLE(x, bits, ifnot) \
130 __builtin_choose_expr( \
131 (sizeof(*(x)) == bits/8), \
132 (__typeof__(*(x)))get_unaligned_le##bits(x), ifnot)
133
134extern void bad_get_le(void);
135#define LAST_GLE(x) \
136 __builtin_choose_expr(sizeof(*(x)) == 1, *(x), bad_get_le())
137
138#define GET_LE(x) \
139 GLE(x, 64, GLE(x, 32, GLE(x, 16, LAST_GLE(x))))
140
141#define PLE(x, val, bits, ifnot) \
142 __builtin_choose_expr( \
143 (sizeof(*(x)) == bits/8), \
144 put_unaligned_le##bits((val), (x)), ifnot)
145
146extern void bad_put_le(void);
147#define LAST_PLE(x, val) \
148 __builtin_choose_expr(sizeof(*(x)) == 1, *(x) = (val), bad_put_le())
149
150#define PUT_LE(x, val) \
151 PLE(x, val, 64, PLE(x, val, 32, PLE(x, val, 16, LAST_PLE(x, val))))
152
153
154#define NSYMS (sizeof(required_syms) / sizeof(required_syms[0]))
155
156#define BITSFUNC3(name, bits, suffix) name##bits##suffix
157#define BITSFUNC2(name, bits, suffix) BITSFUNC3(name, bits, suffix)
158#define BITSFUNC(name) BITSFUNC2(name, ELF_BITS, )
159
160#define INT_BITS BITSFUNC2(int, ELF_BITS, _t)
161
162#define ELF_BITS_XFORM2(bits, x) Elf##bits##_##x
163#define ELF_BITS_XFORM(bits, x) ELF_BITS_XFORM2(bits, x)
164#define ELF(x) ELF_BITS_XFORM(ELF_BITS, x)
165
166#define ELF_BITS 64
167#include "vdso2c.h"
168#undef ELF_BITS
169
170#define ELF_BITS 32
171#include "vdso2c.h"
172#undef ELF_BITS
173
174static void go(void *raw_addr, size_t raw_len,
175 void *stripped_addr, size_t stripped_len,
176 FILE *outfile, const char *name)
177{
178 Elf64_Ehdr *hdr = (Elf64_Ehdr *)raw_addr;
179
180 if (hdr->e_ident[EI_CLASS] == ELFCLASS64) {
181 go64(raw_addr, raw_len, stripped_addr, stripped_len,
182 outfile, name);
183 } else if (hdr->e_ident[EI_CLASS] == ELFCLASS32) {
184 go32(raw_addr, raw_len, stripped_addr, stripped_len,
185 outfile, name);
186 } else {
187 fail("unknown ELF class\n");
188 }
189}
190
191static void map_input(const char *name, void **addr, size_t *len, int prot)
192{
193 off_t tmp_len;
194
195 int fd = open(name, O_RDONLY);
196 if (fd == -1)
197 err(1, "%s", name);
198
199 tmp_len = lseek(fd, 0, SEEK_END);
200 if (tmp_len == (off_t)-1)
201 err(1, "lseek");
202 *len = (size_t)tmp_len;
203
204 *addr = mmap(NULL, tmp_len, prot, MAP_PRIVATE, fd, 0);
205 if (*addr == MAP_FAILED)
206 err(1, "mmap");
207
208 close(fd);
209}
210
211int main(int argc, char **argv)
212{
213 size_t raw_len, stripped_len;
214 void *raw_addr, *stripped_addr;
215 FILE *outfile;
216 char *name, *tmp;
217 int namelen;
218
219 if (argc != 4) {
220 printf("Usage: vdso2c RAW_INPUT STRIPPED_INPUT OUTPUT\n");
221 return 1;
222 }
223
224
225
226
227
228 name = strdup(argv[3]);
229 namelen = strlen(name);
230 if (namelen >= 3 && !strcmp(name + namelen - 3, ".so")) {
231 name = NULL;
232 } else {
233 tmp = strrchr(name, '/');
234 if (tmp)
235 name = tmp + 1;
236 tmp = strchr(name, '.');
237 if (tmp)
238 *tmp = '\0';
239 for (tmp = name; *tmp; tmp++)
240 if (*tmp == '-')
241 *tmp = '_';
242 }
243
244 map_input(argv[1], &raw_addr, &raw_len, PROT_READ);
245 map_input(argv[2], &stripped_addr, &stripped_len, PROT_READ);
246
247 outfilename = argv[3];
248 outfile = fopen(outfilename, "w");
249 if (!outfile)
250 err(1, "%s", argv[2]);
251
252 go(raw_addr, raw_len, stripped_addr, stripped_len, outfile, name);
253
254 munmap(raw_addr, raw_len);
255 munmap(stripped_addr, stripped_len);
256 fclose(outfile);
257
258 return 0;
259}
260