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7static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
8 void *stripped_addr, size_t stripped_len,
9 FILE *outfile, const char *name)
10{
11 int found_load = 0;
12 unsigned long load_size = -1;
13 unsigned long mapping_size;
14 ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr;
15 int i;
16 unsigned long j;
17 ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr,
18 *alt_sec = NULL;
19 ELF(Dyn) *dyn = 0, *dyn_end = 0;
20 const char *secstrings;
21 INT_BITS syms[NSYMS] = {};
22
23 ELF(Phdr) *pt = (ELF(Phdr) *)(raw_addr + GET_LE(&hdr->e_phoff));
24
25
26 for (i = 0; i < GET_LE(&hdr->e_phnum); i++) {
27 if (GET_LE(&pt[i].p_type) == PT_LOAD) {
28 if (found_load)
29 fail("multiple PT_LOAD segs\n");
30
31 if (GET_LE(&pt[i].p_offset) != 0 ||
32 GET_LE(&pt[i].p_vaddr) != 0)
33 fail("PT_LOAD in wrong place\n");
34
35 if (GET_LE(&pt[i].p_memsz) != GET_LE(&pt[i].p_filesz))
36 fail("cannot handle memsz != filesz\n");
37
38 load_size = GET_LE(&pt[i].p_memsz);
39 found_load = 1;
40 } else if (GET_LE(&pt[i].p_type) == PT_DYNAMIC) {
41 dyn = raw_addr + GET_LE(&pt[i].p_offset);
42 dyn_end = raw_addr + GET_LE(&pt[i].p_offset) +
43 GET_LE(&pt[i].p_memsz);
44 }
45 }
46 if (!found_load)
47 fail("no PT_LOAD seg\n");
48
49 if (stripped_len < load_size)
50 fail("stripped input is too short\n");
51
52
53 for (i = 0; dyn + i < dyn_end &&
54 GET_LE(&dyn[i].d_tag) != DT_NULL; i++) {
55 typeof(dyn[i].d_tag) tag = GET_LE(&dyn[i].d_tag);
56 if (tag == DT_REL || tag == DT_RELSZ || tag == DT_RELA ||
57 tag == DT_RELENT || tag == DT_TEXTREL)
58 fail("vdso image contains dynamic relocations\n");
59 }
60
61
62 secstrings_hdr = raw_addr + GET_LE(&hdr->e_shoff) +
63 GET_LE(&hdr->e_shentsize)*GET_LE(&hdr->e_shstrndx);
64 secstrings = raw_addr + GET_LE(&secstrings_hdr->sh_offset);
65 for (i = 0; i < GET_LE(&hdr->e_shnum); i++) {
66 ELF(Shdr) *sh = raw_addr + GET_LE(&hdr->e_shoff) +
67 GET_LE(&hdr->e_shentsize) * i;
68 if (GET_LE(&sh->sh_type) == SHT_SYMTAB)
69 symtab_hdr = sh;
70
71 if (!strcmp(secstrings + GET_LE(&sh->sh_name),
72 ".altinstructions"))
73 alt_sec = sh;
74 }
75
76 if (!symtab_hdr)
77 fail("no symbol table\n");
78
79 strtab_hdr = raw_addr + GET_LE(&hdr->e_shoff) +
80 GET_LE(&hdr->e_shentsize) * GET_LE(&symtab_hdr->sh_link);
81
82
83 for (i = 0;
84 i < GET_LE(&symtab_hdr->sh_size) / GET_LE(&symtab_hdr->sh_entsize);
85 i++) {
86 int k;
87 ELF(Sym) *sym = raw_addr + GET_LE(&symtab_hdr->sh_offset) +
88 GET_LE(&symtab_hdr->sh_entsize) * i;
89 const char *name = raw_addr + GET_LE(&strtab_hdr->sh_offset) +
90 GET_LE(&sym->st_name);
91
92 for (k = 0; k < NSYMS; k++) {
93 if (!strcmp(name, required_syms[k].name)) {
94 if (syms[k]) {
95 fail("duplicate symbol %s\n",
96 required_syms[k].name);
97 }
98
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103
104
105 syms[k] = GET_LE(&sym->st_value);
106 }
107 }
108 }
109
110
111 for (i = 0; i < sizeof(special_pages) / sizeof(special_pages[0]); i++) {
112 INT_BITS symval = syms[special_pages[i]];
113
114 if (!symval)
115 continue;
116
117 if (symval % 4096)
118 fail("%s must be a multiple of 4096\n",
119 required_syms[i].name);
120 if (symval + 4096 < syms[sym_vvar_start])
121 fail("%s underruns vvar_start\n",
122 required_syms[i].name);
123 if (symval + 4096 > 0)
124 fail("%s is on the wrong side of the vdso text\n",
125 required_syms[i].name);
126 }
127 if (syms[sym_vvar_start] % 4096)
128 fail("vvar_begin must be a multiple of 4096\n");
129
130 if (!name) {
131 fwrite(stripped_addr, stripped_len, 1, outfile);
132 return;
133 }
134
135 mapping_size = (stripped_len + 4095) / 4096 * 4096;
136
137 fprintf(outfile, "/* AUTOMATICALLY GENERATED -- DO NOT EDIT */\n\n");
138 fprintf(outfile, "#include <linux/linkage.h>\n");
139 fprintf(outfile, "#include <asm/page_types.h>\n");
140 fprintf(outfile, "#include <asm/vdso.h>\n");
141 fprintf(outfile, "\n");
142 fprintf(outfile,
143 "static unsigned char raw_data[%lu] __page_aligned_data = {",
144 mapping_size);
145 for (j = 0; j < stripped_len; j++) {
146 if (j % 10 == 0)
147 fprintf(outfile, "\n\t");
148 fprintf(outfile, "0x%02X, ",
149 (int)((unsigned char *)stripped_addr)[j]);
150 }
151 fprintf(outfile, "\n};\n\n");
152
153 fprintf(outfile, "static struct page *pages[%lu];\n\n",
154 mapping_size / 4096);
155
156 fprintf(outfile, "const struct vdso_image %s = {\n", name);
157 fprintf(outfile, "\t.data = raw_data,\n");
158 fprintf(outfile, "\t.size = %lu,\n", mapping_size);
159 fprintf(outfile, "\t.text_mapping = {\n");
160 fprintf(outfile, "\t\t.name = \"[vdso]\",\n");
161 fprintf(outfile, "\t\t.pages = pages,\n");
162 fprintf(outfile, "\t},\n");
163 if (alt_sec) {
164 fprintf(outfile, "\t.alt = %lu,\n",
165 (unsigned long)GET_LE(&alt_sec->sh_offset));
166 fprintf(outfile, "\t.alt_len = %lu,\n",
167 (unsigned long)GET_LE(&alt_sec->sh_size));
168 }
169 for (i = 0; i < NSYMS; i++) {
170 if (required_syms[i].export && syms[i])
171 fprintf(outfile, "\t.sym_%s = %" PRIi64 ",\n",
172 required_syms[i].name, (int64_t)syms[i]);
173 }
174 fprintf(outfile, "};\n");
175}
176
