summaryrefslogtreecommitdiffhomepage
path: root/src/logic/pe_get_image_meta.c
blob: 0155e6b7b27b8a937221c3a5ae4c6743c8f78016 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
/***************************************************************/
/*  perk: PE Resource Kit                                      */
/*  Copyright (C) 2015--2016  Z. Gilboa                        */
/*  Released under GPLv2 and GPLv3; see COPYING.PERK.          */
/***************************************************************/

#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include <perk/perk.h>
#include "perk_reader_impl.h"
#include "perk_errinfo_impl.h"

static int pe_free_image_meta_impl(struct pe_image_meta * meta, int ret)
{
	int i;

	if (meta) {
		for (i=0; i<meta->summary.nimplibs; i++)
			free(meta->idata[i].ih_items);

		free(meta->idata);
		free(meta->sectbl);
		free(meta);
	}

	return ret;
}

void pe_free_image_meta(struct pe_image_meta * meta)
{
	pe_free_image_meta_impl(meta,0);
}

int pe_get_named_section_index(const struct pe_image_meta * m, const char * name)
{
	int i; for (i=0; i<m->coff.cfh_num_of_sections; i++)
		if (!(strcmp(name,m->sectbl[i].sh_name)))
			return i;

	return -1;
}

int pe_get_block_section_index(const struct pe_image_meta * m, const struct pe_block * block)
{
	int i;
	uint32_t low,high;

	for (i=0; i<m->coff.cfh_num_of_sections; i++) {
		low  = m->sectbl[i].sh_virtual_addr;
		high = low + m->sectbl[i].sh_virtual_size;

		if ((block->dh_rva >= low) && (block->dh_rva + block->dh_size <= high))
			return i;
	}

	return -1;
}

int pe_get_roffset_from_rva(const struct pe_image_meta * m, uint32_t rva, uint32_t * roffset)
{
	int i;
	uint32_t low,high;

	for (i=0; i<m->coff.cfh_num_of_sections; i++) {
		low  = m->sectbl[i].sh_virtual_addr;
		high = low + m->sectbl[i].sh_virtual_size;

		if ((rva >= low) && (rva < high)) {
			*roffset = (rva - low) + m->sectbl[i].sh_ptr_to_raw_data;
			return 0;
		}
	}

	return -1;
}

int pe_get_rva_from_roffset(const struct pe_image_meta * m, uint32_t roffset, uint32_t * rva)
{
	int i;
	uint32_t low,high,ref;

	for (i=0, ref=~0; i<m->coff.cfh_num_of_sections; i++) {
		low  = m->sectbl[i].sh_ptr_to_raw_data;
		high = low + m->sectbl[i].sh_virtual_size;

		if ((roffset >= low) && (roffset < high)) {
			*rva = (roffset - low) + m->sectbl[i].sh_virtual_addr;
			return 0;
		} else if (ref > low) {
			ref = low;
		}
	}

	if (roffset < ref) {
		*rva = roffset;
		return 0;
	}

	return -1;
}

int pe_get_expsym_by_name(
	const struct pe_image_meta *	m,
	const char *			name,
	struct pe_expsym *		expsym)
{
	uint32_t 	offset;
	uint32_t *	symrva;
	const char *	sym;
	unsigned	i;

	offset	= m->hedata->sh_virtual_addr - m->hedata->sh_ptr_to_raw_data;
	symrva	= (uint32_t *)((uintptr_t)m->image.addr + (m->edata.eh_name_ptr_rva - offset));

	for (i=0; i<m->edata.eh_num_of_name_ptrs; i++) {
		sym = (const char *)m->image.addr + symrva[i] - offset;

		if (!(strcmp(sym,name))) {
			if (expsym) {
				expsym->name    = sym;
				expsym->eaddr   = 0;
				expsym->maddr   = 0;
				expsym->roffset = 0;
			}

			return 0;
		}
	}

	return -1;
}

int pe_get_expsym_by_index(
	const struct pe_image_meta *	m,
	unsigned			index,
	struct pe_expsym *		expsym)
{
	uint32_t 	offset;
	uint32_t *	symrva;
	uintptr_t	symaddr;

	if (index >= m->edata.eh_num_of_name_ptrs)
		return -1;

	if (expsym) {
		offset  = m->hedata->sh_virtual_addr - m->hedata->sh_ptr_to_raw_data;
		symrva  = (uint32_t *)((uintptr_t)m->image.addr + (m->edata.eh_name_ptr_rva - offset));
		symaddr = (uintptr_t)m->image.addr + symrva[index] - offset;

		expsym->name    = (const char *)symaddr;
		expsym->eaddr   = 0;
		expsym->maddr   = 0;
		expsym->roffset = 0;
	}

	return 0;
}

int pe_get_image_meta(
	const struct pe_driver_ctx *	dctx,
	const struct pe_raw_image *	image,
	struct pe_image_meta ** meta)
{
	int			ret;
	int 			i,s;
	long			l;
	unsigned		j;
	const unsigned char *	mark;
	struct pe_image_meta *	m;
	char *			base;

	base = image->addr;

	if (!(m = calloc(1,sizeof(*m))))
		return PERK_SYSTEM_ERROR(dctx);

	m->ados = (struct pe_raw_image_dos_hdr *)base;

	if ((ret = (pe_read_dos_header(m->ados,&m->dos))))
		return pe_free_image_meta_impl(
			m,PERK_CUSTOM_ERROR(dctx,ret));

	m->acoff = (struct pe_raw_coff_file_hdr *)(base + m->dos.dos_lfanew);

	if ((ret = (pe_read_coff_header(m->acoff,&m->coff))))
		return pe_free_image_meta_impl(
			m,PERK_CUSTOM_ERROR(dctx,ret));

	mark  = (const unsigned char *)image->addr + m->coff.cfh_ptr_to_sym_tbl;
	mark += m->coff.cfh_num_of_syms * sizeof(struct pe_raw_coff_symbol);

	m->coff.cfh_ptr_to_str_tbl  = m->coff.cfh_ptr_to_sym_tbl;
	m->coff.cfh_ptr_to_str_tbl += m->coff.cfh_num_of_syms * sizeof(struct pe_raw_coff_symbol);
	m->coff.cfh_size_of_str_tbl = pe_read_long(mark);

	mark    = &m->acoff->cfh_signature[0];
	m->aopt = (union pe_raw_opt_hdr *)(mark + sizeof(*m->acoff));

	if ((ret = (pe_read_optional_header(m->aopt,&m->opt))))
		return pe_free_image_meta_impl(
			m,PERK_CUSTOM_ERROR(dctx,ret));

	mark       = &m->aopt->opt_hdr_32.coh_magic[0];
	m->asectbl = (struct pe_raw_sec_hdr *)(mark + m->coff.cfh_size_of_opt_hdr);

	if (!(m->sectbl = calloc(m->coff.cfh_num_of_sections,sizeof(*(m->sectbl)))))
		return pe_free_image_meta_impl(
			m,PERK_SYSTEM_ERROR(dctx));

	for (i=0; i<m->coff.cfh_num_of_sections; i++) {
		pe_read_section_header(&m->asectbl[i],&m->sectbl[i]);

		if (m->sectbl[i].sh_name[0] == '/')
			if ((l = strtol(&m->sectbl[i].sh_name[1],0,10)) > 0)
				if (l < m->coff.cfh_size_of_str_tbl)
					m->sectbl[i].sh_long_name = base + m->coff.cfh_ptr_to_str_tbl + l;
	}

	/* .edata */
	i = pe_get_named_section_index(m,".edata");
	s = pe_get_block_section_index(m,&m->opt.oh_dirs.coh_export_tbl);

	if ((i >= 0) && (i != s))
		return pe_free_image_meta_impl(
			m,PERK_CUSTOM_ERROR(dctx,PERK_ERR_IMAGE_MALFORMED));

	if (s >= 0) {
		m->hedata = &m->sectbl[s];
		m->aedata = (struct pe_raw_export_hdr *)(base + m->sectbl[s].sh_ptr_to_raw_data
				+ m->opt.oh_dirs.coh_export_tbl.dh_rva - m->sectbl[s].sh_virtual_addr);
	} else if (i >= 0) {
		m->hedata = &m->sectbl[i];
		m->aedata = (struct pe_raw_export_hdr *)(base + m->sectbl[i].sh_ptr_to_raw_data);
	}

	if (m->aedata) {
		pe_read_export_header(m->aedata,&m->edata);
		m->summary.nexpsyms = m->edata.eh_num_of_name_ptrs;
	}

	/* .idata */
	struct pe_raw_import_hdr * 	pidata;
	union  pe_raw_import_lookup *	pitem;

	i = pe_get_named_section_index(m,".idata");
	s = pe_get_block_section_index(m,&m->opt.oh_dirs.coh_import_tbl);

	if ((i >= 0) && (i != s))
		return pe_free_image_meta_impl(
			m,PERK_CUSTOM_ERROR(dctx,PERK_ERR_IMAGE_MALFORMED));

	if (s >= 0) {
		m->hidata = &m->sectbl[s];
		m->aidata = (struct pe_raw_import_hdr *)(base + m->sectbl[s].sh_ptr_to_raw_data
				+ m->opt.oh_dirs.coh_import_tbl.dh_rva - m->sectbl[s].sh_virtual_addr);
	} else if (i >= 0) {
		m->hidata = &m->sectbl[i];
		m->aidata = (struct pe_raw_import_hdr *)(base + m->sectbl[i].sh_ptr_to_raw_data);
	}

	if (m->aidata) {
		/* num of implibs */
		for (pidata=m->aidata; pidata->ih_name_rva[0]; pidata++)
			m->summary.nimplibs++;

		/* import headers */
		if (!(m->idata = calloc(m->summary.nimplibs,sizeof(*m->idata))))
			return pe_free_image_meta_impl(
				m,PERK_SYSTEM_ERROR(dctx));

		for (i=0; i<m->summary.nimplibs; i++) {
			pe_read_import_header(&m->aidata[i],&m->idata[i]);

			m->idata[i].ih_name = base + m->hidata->sh_ptr_to_raw_data
						   + m->idata[i].ih_name_rva
						   - m->hidata->sh_virtual_addr;

			if (m->idata[i].ih_import_lookup_tbl_rva)
				m->idata[i].ih_aitems = (union pe_raw_import_lookup *)(base + m->hidata->sh_ptr_to_raw_data
							+ m->idata[i].ih_import_lookup_tbl_rva
							- m->hidata->sh_virtual_addr);

			/* items */
			uint32_t * hint;
			m->idata[i].ih_count = 0;

			if (m->idata[i].ih_import_lookup_tbl_rva) {
				pitem = m->idata[i].ih_aitems;
				hint  = (uint32_t *)pitem->ii_hint_name_tbl_rva;

				for (; *hint; hint=(uint32_t *)((++pitem)->ii_hint_name_tbl_rva))
					m->idata[i].ih_count++;

				if (!(m->idata[i].ih_items = calloc(m->idata[i].ih_count,sizeof(*(m->idata[i].ih_items)))))
					return pe_free_image_meta_impl(
						m,PERK_SYSTEM_ERROR(dctx));
			}

			for (j=0; j<m->idata[i].ih_count; j++) {
				if ((ret = pe_read_import_lookup(
						&(m->idata[i].ih_aitems[j]),
						&(m->idata[i].ih_items[j]),
						m->opt.oh_std.coh_magic)))
					return pe_free_image_meta_impl(
						m,PERK_CUSTOM_ERROR(dctx,ret));

				switch (m->opt.oh_std.coh_magic) {
					case PE_MAGIC_PE32:
						m->idata[i].ih_items[j].ii_flags = m->idata[i].ih_items[j].u.ii_import_lookup_entry_32;
						break;

					case PE_MAGIC_PE32_PLUS:
						m->idata[i].ih_items[j].ii_flags = (m->idata[i].ih_items[j].u.ii_import_lookup_entry_64 >> 32);
						break;
				}

				if (!m->idata[i].ih_items[j].ii_flags) {
					struct pe_raw_hint_name_entry * pentry =
						(struct pe_raw_hint_name_entry *)(base + m->hidata->sh_ptr_to_raw_data
							+ m->idata[i].ih_items[j].u.ii_hint_name_tbl_rva - m->hidata->sh_virtual_addr);

					m->idata[i].ih_items[j].ii_name = (char *)pentry->ii_name;
				}
			}
		}
	}

	/* image */
	m->image.addr = image->addr;
	m->image.size = image->size;

	/* all done */
	*meta = m;
	return 0;
}