1 /*
2 * Copyright (C) 2023 The Android Open Source Project
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 * * 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 copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the
13 * distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include "linker_auxv.h"
30
31 #include <elf.h>
32 #include <stdio.h>
33 #include <sys/auxv.h>
34 #include <unistd.h>
35
36 #include <async_safe/log.h>
37
auxv_name(int at)38 static const char* auxv_name(int at) {
39 switch (at) {
40 case AT_NULL: return "AT_NULL";
41 case AT_IGNORE: return "AT_IGNORE";
42 case AT_EXECFD: return "AT_EXECFD";
43 case AT_PHDR: return "AT_PHDR";
44 case AT_PHENT: return "AT_PHENT";
45 case AT_PHNUM: return "AT_PHNUM";
46 case AT_PAGESZ: return "AT_PAGESZ";
47 case AT_BASE: return "AT_BASE";
48 case AT_FLAGS: return "AT_FLAGS";
49 case AT_ENTRY: return "AT_ENTRY";
50 case AT_NOTELF: return "AT_NOTELF";
51 case AT_UID: return "AT_UID";
52 case AT_EUID: return "AT_EUID";
53 case AT_GID: return "AT_GID";
54 case AT_EGID: return "AT_EGID";
55 case AT_PLATFORM: return "AT_PLATFORM";
56 case AT_HWCAP: return "AT_HWCAP";
57 case AT_CLKTCK: return "AT_CLKTCK";
58 case AT_SECURE: return "AT_SECURE";
59 case AT_BASE_PLATFORM: return "AT_BASE_PLATFORM";
60 case AT_RANDOM: return "AT_RANDOM";
61 case AT_HWCAP2: return "AT_HWCAP2";
62 case AT_RSEQ_FEATURE_SIZE: return "AT_RSEQ_FEATURE_SIZE";
63 case AT_RSEQ_ALIGN: return "AT_RSEQ_ALIGN";
64 case AT_HWCAP3: return "AT_HWCAP3";
65 case AT_HWCAP4: return "AT_HWCAP4";
66 case AT_EXECFN: return "AT_EXECFN";
67 case AT_SYSINFO_EHDR: return "AT_SYSINFO_EHDR";
68 case AT_MINSIGSTKSZ: return "AT_MINSIGSTKSZ";
69 #if defined(AT_VECTOR_SIZE_ARCH)
70 // AT_VECTOR_SIZE_ARCH isn't a value: it's the number of architecture-specific
71 // values that exist for the current architecture, so not relevant here.
72 #endif
73 #if defined(AT_SYSINFO)
74 case AT_SYSINFO: return "AT_SYSINFO";
75 #endif
76 #if defined(AT_L1I_CACHESIZE)
77 case AT_L1I_CACHESIZE: return "AT_L1I_CACHESIZE";
78 #endif
79 #if defined(AT_L1I_CACHEGEOMETRY)
80 case AT_L1I_CACHEGEOMETRY: return "AT_L1I_CACHEGEOMETRY";
81 #endif
82 #if defined(AT_L1D_CACHESIZE)
83 case AT_L1D_CACHESIZE: return "AT_L1D_CACHESIZE";
84 #endif
85 #if defined(AT_L1D_CACHEGEOMETRY)
86 case AT_L1D_CACHEGEOMETRY: return "AT_L1D_CACHEGEOMETRY";
87 #endif
88 #if defined(AT_L2_CACHESIZE)
89 case AT_L2_CACHESIZE: return "AT_L2_CACHESIZE";
90 #endif
91 #if defined(AT_L2_CACHEGEOMETRY)
92 case AT_L2_CACHEGEOMETRY: return "AT_L2_CACHEGEOMETRY";
93 #endif
94 #if defined(AT_L3_CACHESIZE)
95 case AT_L3_CACHESIZE: return "AT_L3_CACHESIZE";
96 #endif
97 #if defined(AT_L3_CACHEGEOMETRY)
98 case AT_L3_CACHEGEOMETRY: return "AT_L3_CACHEGEOMETRY";
99 #endif
100 }
101 static char name[32];
102 snprintf(name, sizeof(name), "AT_??? (%d)", at);
103 return name;
104 }
105
ld_show_auxv(ElfW (auxv_t)* auxv)106 void ld_show_auxv(ElfW(auxv_t)* auxv) {
107 for (ElfW(auxv_t)* v = auxv; v->a_type != AT_NULL; ++v) {
108 const char* name = auxv_name(v->a_type);
109 long value = v->a_un.a_val;
110 switch (v->a_type) {
111 case AT_SYSINFO_EHDR:
112 case AT_PHDR:
113 case AT_BASE:
114 case AT_ENTRY:
115 case AT_RANDOM:
116 async_safe_format_fd(STDOUT_FILENO, "%-20s %#lx\n", name, value);
117 break;
118 case AT_FLAGS:
119 case AT_HWCAP:
120 case AT_HWCAP2:
121 case AT_HWCAP3:
122 case AT_HWCAP4:
123 async_safe_format_fd(STDOUT_FILENO, "%-20s %#lb\n", name, value);
124 break;
125 case AT_EXECFN:
126 case AT_PLATFORM:
127 async_safe_format_fd(STDOUT_FILENO, "%-20s \"%s\"\n", name, reinterpret_cast<char*>(value));
128 break;
129 default:
130 async_safe_format_fd(STDOUT_FILENO, "%-20s %ld\n", name, value);
131 break;
132 }
133 }
134 }
135