|
1 // Copyright (c) 2007, Google Inc. |
|
2 // All rights reserved. |
|
3 // |
|
4 // Redistribution and use in source and binary forms, with or without |
|
5 // modification, are permitted provided that the following conditions are |
|
6 // met: |
|
7 // |
|
8 // * Redistributions of source code must retain the above copyright |
|
9 // notice, this list of conditions and the following disclaimer. |
|
10 // * Redistributions in binary form must reproduce the above |
|
11 // copyright notice, this list of conditions and the following disclaimer |
|
12 // in the documentation and/or other materials provided with the |
|
13 // distribution. |
|
14 // * Neither the name of Google Inc. nor the names of its |
|
15 // contributors may be used to endorse or promote products derived from |
|
16 // this software without specific prior written permission. |
|
17 // |
|
18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
|
19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
|
20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
|
21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
|
22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
|
23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
|
24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
|
25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
|
26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
|
27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
|
28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
|
29 |
|
30 // file_id.cc: Return a unique identifier for a file |
|
31 // |
|
32 // See file_id.h for documentation |
|
33 // |
|
34 // Author: Alfred Peng |
|
35 |
|
36 #include <elf.h> |
|
37 #include <fcntl.h> |
|
38 #include <gelf.h> |
|
39 #include <sys/mman.h> |
|
40 #include <sys/ksyms.h> |
|
41 #include <stdio.h> |
|
42 #include <string.h> |
|
43 #include <unistd.h> |
|
44 |
|
45 #include <cassert> |
|
46 #include <cstdio> |
|
47 |
|
48 #include "common/md5.h" |
|
49 #include "common/solaris/file_id.h" |
|
50 #include "common/solaris/message_output.h" |
|
51 #include "google_breakpad/common/minidump_format.h" |
|
52 |
|
53 namespace google_breakpad { |
|
54 |
|
55 class AutoElfEnder { |
|
56 public: |
|
57 AutoElfEnder(Elf *elf) : elf_(elf) {} |
|
58 ~AutoElfEnder() { if (elf_) elf_end(elf_); } |
|
59 private: |
|
60 Elf *elf_; |
|
61 }; |
|
62 |
|
63 // Find the text section in elf object file. |
|
64 // Return the section start address and the size. |
|
65 static bool FindElfTextSection(int fd, const void *elf_base, |
|
66 const void **text_start, |
|
67 int *text_size) { |
|
68 assert(text_start); |
|
69 assert(text_size); |
|
70 |
|
71 *text_start = NULL; |
|
72 *text_size = 0; |
|
73 |
|
74 if (elf_version(EV_CURRENT) == EV_NONE) { |
|
75 print_message2(2, "elf_version() failed: %s\n", elf_errmsg(0)); |
|
76 return false; |
|
77 } |
|
78 |
|
79 GElf_Ehdr elf_header; |
|
80 lseek(fd, 0L, 0); |
|
81 Elf *elf = elf_begin(fd, ELF_C_READ, NULL); |
|
82 AutoElfEnder elfEnder(elf); |
|
83 |
|
84 if (gelf_getehdr(elf, &elf_header) == (GElf_Ehdr *)NULL) { |
|
85 print_message2(2, "failed to read elf header: %s\n", elf_errmsg(-1)); |
|
86 return false; |
|
87 } |
|
88 |
|
89 if (elf_header.e_ident[EI_MAG0] != ELFMAG0 || |
|
90 elf_header.e_ident[EI_MAG1] != ELFMAG1 || |
|
91 elf_header.e_ident[EI_MAG2] != ELFMAG2 || |
|
92 elf_header.e_ident[EI_MAG3] != ELFMAG3) { |
|
93 print_message1(2, "header magic doesn't match\n"); |
|
94 return false; |
|
95 } |
|
96 |
|
97 static const char kTextSectionName[] = ".text"; |
|
98 const GElf_Shdr *text_section = NULL; |
|
99 Elf_Scn *scn = NULL; |
|
100 GElf_Shdr shdr; |
|
101 |
|
102 while ((scn = elf_nextscn(elf, scn)) != NULL) { |
|
103 if (gelf_getshdr(scn, &shdr) == (GElf_Shdr *)0) { |
|
104 print_message2(2, "failed to read section header: %s\n", elf_errmsg(0)); |
|
105 return false; |
|
106 } |
|
107 |
|
108 if (shdr.sh_type == SHT_PROGBITS) { |
|
109 const char *section_name = elf_strptr(elf, elf_header.e_shstrndx, |
|
110 shdr.sh_name); |
|
111 if (!section_name) { |
|
112 print_message2(2, "Section name error: %s\n", elf_errmsg(-1)); |
|
113 continue; |
|
114 } |
|
115 |
|
116 if (strcmp(section_name, kTextSectionName) == 0) { |
|
117 text_section = &shdr; |
|
118 break; |
|
119 } |
|
120 } |
|
121 } |
|
122 if (text_section != NULL && text_section->sh_size > 0) { |
|
123 *text_start = (char *)elf_base + text_section->sh_offset; |
|
124 *text_size = text_section->sh_size; |
|
125 return true; |
|
126 } |
|
127 |
|
128 return false; |
|
129 } |
|
130 |
|
131 FileID::FileID(const char *path) { |
|
132 strcpy(path_, path); |
|
133 } |
|
134 |
|
135 class AutoCloser { |
|
136 public: |
|
137 AutoCloser(int fd) : fd_(fd) {} |
|
138 ~AutoCloser() { if (fd_) close(fd_); } |
|
139 private: |
|
140 int fd_; |
|
141 }; |
|
142 |
|
143 bool FileID::ElfFileIdentifier(unsigned char identifier[16]) { |
|
144 int fd = 0; |
|
145 if ((fd = open(path_, O_RDONLY)) < 0) |
|
146 return false; |
|
147 |
|
148 AutoCloser autocloser(fd); |
|
149 struct stat st; |
|
150 if (fstat(fd, &st) != 0 || st.st_size <= 0) |
|
151 return false; |
|
152 |
|
153 void *base = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0); |
|
154 if (base == MAP_FAILED) |
|
155 return false; |
|
156 |
|
157 bool success = false; |
|
158 const void *text_section = NULL; |
|
159 int text_size = 0; |
|
160 |
|
161 if (FindElfTextSection(fd, base, &text_section, &text_size)) { |
|
162 MD5Context md5; |
|
163 MD5Init(&md5); |
|
164 MD5Update(&md5, (const unsigned char *)text_section, text_size); |
|
165 MD5Final(identifier, &md5); |
|
166 success = true; |
|
167 } |
|
168 |
|
169 munmap((char *)base, st.st_size); |
|
170 return success; |
|
171 } |
|
172 |
|
173 // static |
|
174 bool FileID::ConvertIdentifierToString(const unsigned char identifier[16], |
|
175 char *buffer, int buffer_length) { |
|
176 if (buffer_length < 34) |
|
177 return false; |
|
178 |
|
179 int buffer_idx = 0; |
|
180 for (int idx = 0; idx < 16; ++idx) { |
|
181 int hi = (identifier[idx] >> 4) & 0x0F; |
|
182 int lo = (identifier[idx]) & 0x0F; |
|
183 |
|
184 buffer[buffer_idx++] = (hi >= 10) ? 'A' + hi - 10 : '0' + hi; |
|
185 buffer[buffer_idx++] = (lo >= 10) ? 'A' + lo - 10 : '0' + lo; |
|
186 } |
|
187 |
|
188 // Add an extra "0" by the end. |
|
189 buffer[buffer_idx++] = '0'; |
|
190 |
|
191 // NULL terminate |
|
192 buffer[buffer_idx] = 0; |
|
193 |
|
194 return true; |
|
195 } |
|
196 |
|
197 } // namespace google_breakpad |