1 /*-
2  * Copyright (c) 2009-2011 Kai Wang
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include "_libdwarf.h"
28 
29 ELFTC_VCSID("$Id: libdwarf_arange.c 3029 2014-04-21 23:26:02Z kaiwang27 $");
30 
31 void
32 _dwarf_arange_cleanup(Dwarf_Debug dbg)
33 {
34 	Dwarf_ArangeSet as, tas;
35 	Dwarf_Arange ar, tar;
36 
37 	STAILQ_FOREACH_SAFE(as, &dbg->dbg_aslist, as_next, tas) {
38 		STAILQ_FOREACH_SAFE(ar, &as->as_arlist, ar_next, tar) {
39 			STAILQ_REMOVE(&as->as_arlist, ar, _Dwarf_Arange,
40 			    ar_next);
41 			free(ar);
42 		}
43 		STAILQ_REMOVE(&dbg->dbg_aslist, as, _Dwarf_ArangeSet, as_next);
44 		free(as);
45 	}
46 
47 	if (dbg->dbg_arange_array)
48 		free(dbg->dbg_arange_array);
49 
50 	dbg->dbg_arange_array = NULL;
51 	dbg->dbg_arange_cnt = 0;
52 }
53 
54 int
55 _dwarf_arange_init(Dwarf_Debug dbg, Dwarf_Error *error)
56 {
57 	Dwarf_CU cu;
58 	Dwarf_ArangeSet as;
59 	Dwarf_Arange ar;
60 	Dwarf_Section *ds;
61 	uint64_t offset, dwarf_size, length, addr, range;
62 	int i, ret;
63 
64 	ret = DW_DLE_NONE;
65 
66 	if ((ds = _dwarf_find_section(dbg, ".debug_aranges")) == NULL)
67 		return (DW_DLE_NONE);
68 
69 	if (!dbg->dbg_info_loaded) {
70 		ret = _dwarf_info_load(dbg, 1, 1, error);
71 		if (ret != DW_DLE_NONE)
72 			return (ret);
73 	}
74 
75 	offset = 0;
76 	while (offset < ds->ds_size) {
77 
78 		if ((as = malloc(sizeof(struct _Dwarf_ArangeSet))) == NULL) {
79 			DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
80 			return (DW_DLE_MEMORY);
81 		}
82 		STAILQ_INIT(&as->as_arlist);
83 		STAILQ_INSERT_TAIL(&dbg->dbg_aslist, as, as_next);
84 
85 		/* Read in the table header. */
86 		length = dbg->read(ds->ds_data, &offset, 4);
87 		if (length == 0xffffffff) {
88 			dwarf_size = 8;
89 			length = dbg->read(ds->ds_data, &offset, 8);
90 		} else
91 			dwarf_size = 4;
92 
93 		as->as_length = length;
94 		as->as_version = dbg->read(ds->ds_data, &offset, 2);
95 		if (as->as_version != 2) {
96 			DWARF_SET_ERROR(dbg, error, DW_DLE_VERSION_STAMP_ERROR);
97 			ret = DW_DLE_VERSION_STAMP_ERROR;
98 			goto fail_cleanup;
99 		}
100 
101 		as->as_cu_offset = dbg->read(ds->ds_data, &offset, dwarf_size);
102 		STAILQ_FOREACH(cu, &dbg->dbg_cu, cu_next) {
103 			if (cu->cu_offset == as->as_cu_offset)
104 				break;
105 		}
106 		if (cu == NULL) {
107 			DWARF_SET_ERROR(dbg, error, DW_DLE_ARANGE_OFFSET_BAD);
108 			ret = DW_DLE_ARANGE_OFFSET_BAD;
109 			goto fail_cleanup;
110 		}
111 		as->as_cu = cu;
112 
113 		as->as_addrsz = dbg->read(ds->ds_data, &offset, 1);
114 		as->as_segsz = dbg->read(ds->ds_data, &offset, 1);
115 
116 		/* Skip the padding bytes.  */
117 		offset = roundup(offset, 2 * as->as_addrsz);
118 
119 		/* Read in address range descriptors. */
120 		while (offset < ds->ds_size) {
121 			addr = dbg->read(ds->ds_data, &offset, as->as_addrsz);
122 			range = dbg->read(ds->ds_data, &offset, as->as_addrsz);
123 			if (addr == 0 && range == 0)
124 				break;
125 			if ((ar = calloc(1, sizeof(struct _Dwarf_Arange))) ==
126 			    NULL) {
127 				DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
128 				goto fail_cleanup;
129 			}
130 			ar->ar_as = as;
131 			ar->ar_address = addr;
132 			ar->ar_range = range;
133 			STAILQ_INSERT_TAIL(&as->as_arlist, ar, ar_next);
134 			dbg->dbg_arange_cnt++;
135 		}
136 	}
137 
138 	/* Build arange array. */
139 	if (dbg->dbg_arange_cnt > 0) {
140 		if ((dbg->dbg_arange_array = malloc(dbg->dbg_arange_cnt *
141 		    sizeof(Dwarf_Arange))) == NULL) {
142 			DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
143 			ret = DW_DLE_MEMORY;
144 			goto fail_cleanup;
145 		}
146 
147 		i = 0;
148 		STAILQ_FOREACH(as, &dbg->dbg_aslist, as_next) {
149 			STAILQ_FOREACH(ar, &as->as_arlist, ar_next)
150 				dbg->dbg_arange_array[i++] = ar;
151 		}
152 		assert((Dwarf_Unsigned)i == dbg->dbg_arange_cnt);
153 	}
154 
155 	return (DW_DLE_NONE);
156 
157 fail_cleanup:
158 
159 	_dwarf_arange_cleanup(dbg);
160 
161 	return (ret);
162 }
163 
164 int
165 _dwarf_arange_gen(Dwarf_P_Debug dbg, Dwarf_Error *error)
166 {
167 	Dwarf_P_Section ds;
168 	Dwarf_Rel_Section drs;
169 	Dwarf_ArangeSet as;
170 	Dwarf_Arange ar;
171 	uint64_t offset;
172 	int ret;
173 
174 	as = dbg->dbgp_as;
175 	assert(as != NULL);
176 	if (STAILQ_EMPTY(&as->as_arlist))
177 		return (DW_DLE_NONE);
178 
179 	as->as_length = 0;
180 	as->as_version = 2;
181 	as->as_cu_offset = 0;	/* We have only one CU. */
182 	as->as_addrsz = dbg->dbg_pointer_size;
183 	as->as_segsz = 0;	/* XXX */
184 
185 	/* Create .debug_arange section. */
186 	if ((ret = _dwarf_section_init(dbg, &ds, ".debug_aranges", 0, error)) !=
187 	    DW_DLE_NONE)
188 		goto gen_fail0;
189 
190 	/* Create relocation section for .debug_aranges */
191 	RCHECK(_dwarf_reloc_section_init(dbg, &drs, ds, error));
192 
193 	/* Write section header. */
194 	RCHECK(WRITE_VALUE(as->as_length, 4));
195 	RCHECK(WRITE_VALUE(as->as_version, 2));
196 	RCHECK(_dwarf_reloc_entry_add(dbg, drs, ds, dwarf_drt_data_reloc, 4,
197 	    ds->ds_size, 0, as->as_cu_offset, ".debug_info", error));
198 	RCHECK(WRITE_VALUE(as->as_addrsz, 1));
199 	RCHECK(WRITE_VALUE(as->as_segsz, 1));
200 
201 	/* Pad to (2 * address_size) */
202 	offset = roundup(ds->ds_size, 2 * as->as_addrsz);
203 	if (offset > ds->ds_size)
204 		RCHECK(WRITE_PADDING(0, offset - ds->ds_size));
205 
206 	/* Write tuples. */
207 	STAILQ_FOREACH(ar, &as->as_arlist, ar_next) {
208 		RCHECK(_dwarf_reloc_entry_add(dbg, drs, ds,
209 		    dwarf_drt_data_reloc, dbg->dbg_pointer_size, ds->ds_size,
210 		    ar->ar_symndx, ar->ar_address, NULL, error));
211 		if (ar->ar_esymndx > 0)
212 			RCHECK(_dwarf_reloc_entry_add_pair(dbg, drs, ds,
213 			    dbg->dbg_pointer_size, ds->ds_size, ar->ar_symndx,
214 			    ar->ar_esymndx, ar->ar_address, ar->ar_eoff, error));
215 		else
216 			RCHECK(WRITE_VALUE(ar->ar_range, dbg->dbg_pointer_size));
217 	}
218 	RCHECK(WRITE_VALUE(0, dbg->dbg_pointer_size));
219 	RCHECK(WRITE_VALUE(0, dbg->dbg_pointer_size));
220 
221 	/* Fill in the length field. */
222 	as->as_length = ds->ds_size - 4;
223 	offset = 0;
224 	dbg->write(ds->ds_data, &offset, as->as_length, 4);
225 
226 	/* Inform application the creation of .debug_aranges ELF section. */
227 	RCHECK(_dwarf_section_callback(dbg, ds, SHT_PROGBITS, 0, 0, 0, error));
228 
229 	/* Finalize relocation section for .debug_aranges */
230 	RCHECK(_dwarf_reloc_section_finalize(dbg, drs, error));
231 
232 	return (DW_DLE_NONE);
233 
234 gen_fail:
235 	_dwarf_reloc_section_free(dbg, &drs);
236 
237 gen_fail0:
238 	_dwarf_section_free(dbg, &ds);
239 
240 	return (ret);
241 }
242 
243 void
244 _dwarf_arange_pro_cleanup(Dwarf_P_Debug dbg)
245 {
246 	Dwarf_ArangeSet as;
247 	Dwarf_Arange ar, tar;
248 
249 	assert(dbg != NULL && dbg->dbg_mode == DW_DLC_WRITE);
250 	if (dbg->dbgp_as == NULL)
251 		return;
252 
253 	as = dbg->dbgp_as;
254 	STAILQ_FOREACH_SAFE(ar, &as->as_arlist, ar_next, tar) {
255 		STAILQ_REMOVE(&as->as_arlist, ar, _Dwarf_Arange, ar_next);
256 		free(ar);
257 	}
258 	free(as);
259 	dbg->dbgp_as = NULL;
260 }
261