1#include "dso.h"
2#include "symbol.h"
3#include "symsrc.h"
4
5#include <errno.h>
6#include <unistd.h>
7#include <stdio.h>
8#include <fcntl.h>
9#include <string.h>
10#include <stdlib.h>
11#include <byteswap.h>
12#include <sys/stat.h>
13#include <linux/zalloc.h>
14#include <internal/lib.h>
15
16static bool check_need_swap(int file_endian)
17{
18 const int data = 1;
19 u8 *check = (u8 *)&data;
20 int host_endian;
21
22 if (check[0] == 1)
23 host_endian = ELFDATA2LSB;
24 else
25 host_endian = ELFDATA2MSB;
26
27 return host_endian != file_endian;
28}
29
30#define NOTE_ALIGN(sz) (((sz) + 3) & ~3)
31
32#define NT_GNU_BUILD_ID 3
33
34static int read_build_id(void *note_data, size_t note_len, struct build_id *bid,
35 bool need_swap)
36{
37 size_t size = sizeof(bid->data);
38 struct {
39 u32 n_namesz;
40 u32 n_descsz;
41 u32 n_type;
42 } *nhdr;
43 void *ptr;
44
45 ptr = note_data;
46 while (ptr < (note_data + note_len)) {
47 const char *name;
48 size_t namesz, descsz;
49
50 nhdr = ptr;
51 if (need_swap) {
52 nhdr->n_namesz = bswap_32(nhdr->n_namesz);
53 nhdr->n_descsz = bswap_32(nhdr->n_descsz);
54 nhdr->n_type = bswap_32(nhdr->n_type);
55 }
56
57 namesz = NOTE_ALIGN(nhdr->n_namesz);
58 descsz = NOTE_ALIGN(nhdr->n_descsz);
59
60 ptr += sizeof(*nhdr);
61 name = ptr;
62 ptr += namesz;
63 if (nhdr->n_type == NT_GNU_BUILD_ID &&
64 nhdr->n_namesz == sizeof("GNU")) {
65 if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
66 size_t sz = min(size, descsz);
67 memcpy(bid->data, ptr, sz);
68 memset(bid->data + sz, 0, size - sz);
69 bid->size = sz;
70 return 0;
71 }
72 }
73 ptr += descsz;
74 }
75
76 return -1;
77}
78
79int filename__read_debuglink(const char *filename __maybe_unused,
80 char *debuglink __maybe_unused,
81 size_t size __maybe_unused)
82{
83 return -1;
84}
85
86
87
88
89int filename__read_build_id(const char *filename, struct build_id *bid)
90{
91 FILE *fp;
92 int ret = -1;
93 bool need_swap = false;
94 u8 e_ident[EI_NIDENT];
95 size_t buf_size;
96 void *buf;
97 int i;
98
99 fp = fopen(filename, "r");
100 if (fp == NULL)
101 return -1;
102
103 if (fread(e_ident, sizeof(e_ident), 1, fp) != 1)
104 goto out;
105
106 if (memcmp(e_ident, ELFMAG, SELFMAG) ||
107 e_ident[EI_VERSION] != EV_CURRENT)
108 goto out;
109
110 need_swap = check_need_swap(e_ident[EI_DATA]);
111
112
113 fseek(fp, 0, SEEK_SET);
114
115 if (e_ident[EI_CLASS] == ELFCLASS32) {
116 Elf32_Ehdr ehdr;
117 Elf32_Phdr *phdr;
118
119 if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1)
120 goto out;
121
122 if (need_swap) {
123 ehdr.e_phoff = bswap_32(ehdr.e_phoff);
124 ehdr.e_phentsize = bswap_16(ehdr.e_phentsize);
125 ehdr.e_phnum = bswap_16(ehdr.e_phnum);
126 }
127
128 buf_size = ehdr.e_phentsize * ehdr.e_phnum;
129 buf = malloc(buf_size);
130 if (buf == NULL)
131 goto out;
132
133 fseek(fp, ehdr.e_phoff, SEEK_SET);
134 if (fread(buf, buf_size, 1, fp) != 1)
135 goto out_free;
136
137 for (i = 0, phdr = buf; i < ehdr.e_phnum; i++, phdr++) {
138 void *tmp;
139 long offset;
140
141 if (need_swap) {
142 phdr->p_type = bswap_32(phdr->p_type);
143 phdr->p_offset = bswap_32(phdr->p_offset);
144 phdr->p_filesz = bswap_32(phdr->p_filesz);
145 }
146
147 if (phdr->p_type != PT_NOTE)
148 continue;
149
150 buf_size = phdr->p_filesz;
151 offset = phdr->p_offset;
152 tmp = realloc(buf, buf_size);
153 if (tmp == NULL)
154 goto out_free;
155
156 buf = tmp;
157 fseek(fp, offset, SEEK_SET);
158 if (fread(buf, buf_size, 1, fp) != 1)
159 goto out_free;
160
161 ret = read_build_id(buf, buf_size, bid, need_swap);
162 if (ret == 0)
163 ret = bid->size;
164 break;
165 }
166 } else {
167 Elf64_Ehdr ehdr;
168 Elf64_Phdr *phdr;
169
170 if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1)
171 goto out;
172
173 if (need_swap) {
174 ehdr.e_phoff = bswap_64(ehdr.e_phoff);
175 ehdr.e_phentsize = bswap_16(ehdr.e_phentsize);
176 ehdr.e_phnum = bswap_16(ehdr.e_phnum);
177 }
178
179 buf_size = ehdr.e_phentsize * ehdr.e_phnum;
180 buf = malloc(buf_size);
181 if (buf == NULL)
182 goto out;
183
184 fseek(fp, ehdr.e_phoff, SEEK_SET);
185 if (fread(buf, buf_size, 1, fp) != 1)
186 goto out_free;
187
188 for (i = 0, phdr = buf; i < ehdr.e_phnum; i++, phdr++) {
189 void *tmp;
190 long offset;
191
192 if (need_swap) {
193 phdr->p_type = bswap_32(phdr->p_type);
194 phdr->p_offset = bswap_64(phdr->p_offset);
195 phdr->p_filesz = bswap_64(phdr->p_filesz);
196 }
197
198 if (phdr->p_type != PT_NOTE)
199 continue;
200
201 buf_size = phdr->p_filesz;
202 offset = phdr->p_offset;
203 tmp = realloc(buf, buf_size);
204 if (tmp == NULL)
205 goto out_free;
206
207 buf = tmp;
208 fseek(fp, offset, SEEK_SET);
209 if (fread(buf, buf_size, 1, fp) != 1)
210 goto out_free;
211
212 ret = read_build_id(buf, buf_size, bid, need_swap);
213 if (ret == 0)
214 ret = bid->size;
215 break;
216 }
217 }
218out_free:
219 free(buf);
220out:
221 fclose(fp);
222 return ret;
223}
224
225int sysfs__read_build_id(const char *filename, struct build_id *bid)
226{
227 int fd;
228 int ret = -1;
229 struct stat stbuf;
230 size_t buf_size;
231 void *buf;
232
233 fd = open(filename, O_RDONLY);
234 if (fd < 0)
235 return -1;
236
237 if (fstat(fd, &stbuf) < 0)
238 goto out;
239
240 buf_size = stbuf.st_size;
241 buf = malloc(buf_size);
242 if (buf == NULL)
243 goto out;
244
245 if (read(fd, buf, buf_size) != (ssize_t) buf_size)
246 goto out_free;
247
248 ret = read_build_id(buf, buf_size, bid, false);
249out_free:
250 free(buf);
251out:
252 close(fd);
253 return ret;
254}
255
256int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
257 enum dso_binary_type type)
258{
259 int fd = open(name, O_RDONLY);
260 if (fd < 0)
261 goto out_errno;
262
263 ss->name = strdup(name);
264 if (!ss->name)
265 goto out_close;
266
267 ss->fd = fd;
268 ss->type = type;
269
270 return 0;
271out_close:
272 close(fd);
273out_errno:
274 dso->load_errno = errno;
275 return -1;
276}
277
278bool symsrc__possibly_runtime(struct symsrc *ss __maybe_unused)
279{
280
281 return true;
282}
283
284bool symsrc__has_symtab(struct symsrc *ss __maybe_unused)
285{
286 return false;
287}
288
289void symsrc__destroy(struct symsrc *ss)
290{
291 zfree(&ss->name);
292 close(ss->fd);
293}
294
295int dso__synthesize_plt_symbols(struct dso *dso __maybe_unused,
296 struct symsrc *ss __maybe_unused)
297{
298 return 0;
299}
300
301static int fd__is_64_bit(int fd)
302{
303 u8 e_ident[EI_NIDENT];
304
305 if (lseek(fd, 0, SEEK_SET))
306 return -1;
307
308 if (readn(fd, e_ident, sizeof(e_ident)) != sizeof(e_ident))
309 return -1;
310
311 if (memcmp(e_ident, ELFMAG, SELFMAG) ||
312 e_ident[EI_VERSION] != EV_CURRENT)
313 return -1;
314
315 return e_ident[EI_CLASS] == ELFCLASS64;
316}
317
318enum dso_type dso__type_fd(int fd)
319{
320 Elf64_Ehdr ehdr;
321 int ret;
322
323 ret = fd__is_64_bit(fd);
324 if (ret < 0)
325 return DSO__TYPE_UNKNOWN;
326
327 if (ret)
328 return DSO__TYPE_64BIT;
329
330 if (readn(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
331 return DSO__TYPE_UNKNOWN;
332
333 if (ehdr.e_machine == EM_X86_64)
334 return DSO__TYPE_X32BIT;
335
336 return DSO__TYPE_32BIT;
337}
338
339int dso__load_sym(struct dso *dso, struct map *map __maybe_unused,
340 struct symsrc *ss,
341 struct symsrc *runtime_ss __maybe_unused,
342 int kmodule __maybe_unused)
343{
344 struct build_id bid;
345 int ret;
346
347 ret = fd__is_64_bit(ss->fd);
348 if (ret >= 0)
349 dso->is_64_bit = ret;
350
351 if (filename__read_build_id(ss->name, &bid) > 0)
352 dso__set_build_id(dso, &bid);
353 return 0;
354}
355
356int file__read_maps(int fd __maybe_unused, bool exe __maybe_unused,
357 mapfn_t mapfn __maybe_unused, void *data __maybe_unused,
358 bool *is_64_bit __maybe_unused)
359{
360 return -1;
361}
362
363int kcore_extract__create(struct kcore_extract *kce __maybe_unused)
364{
365 return -1;
366}
367
368void kcore_extract__delete(struct kcore_extract *kce __maybe_unused)
369{
370}
371
372int kcore_copy(const char *from_dir __maybe_unused,
373 const char *to_dir __maybe_unused)
374{
375 return -1;
376}
377
378void symbol__elf_init(void)
379{
380}
381
382char *dso__demangle_sym(struct dso *dso __maybe_unused,
383 int kmodule __maybe_unused,
384 const char *elf_name __maybe_unused)
385{
386 return NULL;
387}
388
