xref: /linux/scripts/mod/modpost.h (revision 9dbbc3b9d09d6deba9f3b9e1d5b355032ed46a75)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #include <stdio.h>
3 #include <stdlib.h>
4 #include <stdarg.h>
5 #include <stdbool.h>
6 #include <string.h>
7 #include <sys/types.h>
8 #include <sys/stat.h>
9 #include <sys/mman.h>
10 #include <fcntl.h>
11 #include <unistd.h>
12 #include <elf.h>
13 
14 #include "elfconfig.h"
15 
16 /* On BSD-alike OSes elf.h defines these according to host's word size */
17 #undef ELF_ST_BIND
18 #undef ELF_ST_TYPE
19 #undef ELF_R_SYM
20 #undef ELF_R_TYPE
21 
22 #if KERNEL_ELFCLASS == ELFCLASS32
23 
24 #define Elf_Ehdr    Elf32_Ehdr
25 #define Elf_Shdr    Elf32_Shdr
26 #define Elf_Sym     Elf32_Sym
27 #define Elf_Addr    Elf32_Addr
28 #define Elf_Sword   Elf64_Sword
29 #define Elf_Section Elf32_Half
30 #define ELF_ST_BIND ELF32_ST_BIND
31 #define ELF_ST_TYPE ELF32_ST_TYPE
32 
33 #define Elf_Rel     Elf32_Rel
34 #define Elf_Rela    Elf32_Rela
35 #define ELF_R_SYM   ELF32_R_SYM
36 #define ELF_R_TYPE  ELF32_R_TYPE
37 #else
38 
39 #define Elf_Ehdr    Elf64_Ehdr
40 #define Elf_Shdr    Elf64_Shdr
41 #define Elf_Sym     Elf64_Sym
42 #define Elf_Addr    Elf64_Addr
43 #define Elf_Sword   Elf64_Sxword
44 #define Elf_Section Elf64_Half
45 #define ELF_ST_BIND ELF64_ST_BIND
46 #define ELF_ST_TYPE ELF64_ST_TYPE
47 
48 #define Elf_Rel     Elf64_Rel
49 #define Elf_Rela    Elf64_Rela
50 #define ELF_R_SYM   ELF64_R_SYM
51 #define ELF_R_TYPE  ELF64_R_TYPE
52 #endif
53 
54 /* The 64-bit MIPS ELF ABI uses an unusual reloc format. */
55 typedef struct
56 {
57 	Elf32_Word    r_sym;	/* Symbol index */
58 	unsigned char r_ssym;	/* Special symbol for 2nd relocation */
59 	unsigned char r_type3;	/* 3rd relocation type */
60 	unsigned char r_type2;	/* 2nd relocation type */
61 	unsigned char r_type1;	/* 1st relocation type */
62 } _Elf64_Mips_R_Info;
63 
64 typedef union
65 {
66 	Elf64_Xword		r_info_number;
67 	_Elf64_Mips_R_Info	r_info_fields;
68 } _Elf64_Mips_R_Info_union;
69 
70 #define ELF64_MIPS_R_SYM(i) \
71   ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym)
72 
73 #define ELF64_MIPS_R_TYPE(i) \
74   ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1)
75 
76 #if KERNEL_ELFDATA != HOST_ELFDATA
77 
78 static inline void __endian(const void *src, void *dest, unsigned int size)
79 {
80 	unsigned int i;
81 	for (i = 0; i < size; i++)
82 		((unsigned char*)dest)[i] = ((unsigned char*)src)[size - i-1];
83 }
84 
85 #define TO_NATIVE(x)						\
86 ({								\
87 	typeof(x) __x;						\
88 	__endian(&(x), &(__x), sizeof(__x));			\
89 	__x;							\
90 })
91 
92 #else /* endianness matches */
93 
94 #define TO_NATIVE(x) (x)
95 
96 #endif
97 
98 #define NOFAIL(ptr)   do_nofail((ptr), #ptr)
99 void *do_nofail(void *ptr, const char *expr);
100 
101 struct buffer {
102 	char *p;
103 	int pos;
104 	int size;
105 };
106 
107 void __attribute__((format(printf, 2, 3)))
108 buf_printf(struct buffer *buf, const char *fmt, ...);
109 
110 void
111 buf_write(struct buffer *buf, const char *s, int len);
112 
113 struct namespace_list {
114 	struct namespace_list *next;
115 	char namespace[];
116 };
117 
118 struct module {
119 	struct module *next;
120 	int gpl_compatible;
121 	struct symbol *unres;
122 	int from_dump;  /* 1 if module was loaded from *.symvers */
123 	int is_vmlinux;
124 	int seen;
125 	int has_init;
126 	int has_cleanup;
127 	struct buffer dev_table_buf;
128 	char	     srcversion[25];
129 	// Missing namespace dependencies
130 	struct namespace_list *missing_namespaces;
131 	// Actual imported namespaces
132 	struct namespace_list *imported_namespaces;
133 	char name[];
134 };
135 
136 struct elf_info {
137 	size_t size;
138 	Elf_Ehdr     *hdr;
139 	Elf_Shdr     *sechdrs;
140 	Elf_Sym      *symtab_start;
141 	Elf_Sym      *symtab_stop;
142 	Elf_Section  export_sec;
143 	Elf_Section  export_gpl_sec;
144 	char         *strtab;
145 	char	     *modinfo;
146 	unsigned int modinfo_len;
147 
148 	/* support for 32bit section numbers */
149 
150 	unsigned int num_sections; /* max_secindex + 1 */
151 	unsigned int secindex_strings;
152 	/* if Nth symbol table entry has .st_shndx = SHN_XINDEX,
153 	 * take shndx from symtab_shndx_start[N] instead */
154 	Elf32_Word   *symtab_shndx_start;
155 	Elf32_Word   *symtab_shndx_stop;
156 };
157 
158 static inline int is_shndx_special(unsigned int i)
159 {
160 	return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
161 }
162 
163 /*
164  * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
165  * the way to -256..-1, to avoid conflicting with real section
166  * indices.
167  */
168 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))
169 
170 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
171 static inline unsigned int get_secindex(const struct elf_info *info,
172 					const Elf_Sym *sym)
173 {
174 	if (is_shndx_special(sym->st_shndx))
175 		return SPECIAL(sym->st_shndx);
176 	if (sym->st_shndx != SHN_XINDEX)
177 		return sym->st_shndx;
178 	return info->symtab_shndx_start[sym - info->symtab_start];
179 }
180 
181 static inline bool strends(const char *str, const char *postfix)
182 {
183 	if (strlen(str) < strlen(postfix))
184 		return false;
185 
186 	return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
187 }
188 
189 /* file2alias.c */
190 extern unsigned int cross_build;
191 void handle_moddevtable(struct module *mod, struct elf_info *info,
192 			Elf_Sym *sym, const char *symname);
193 void add_moddevtable(struct buffer *buf, struct module *mod);
194 
195 /* sumversion.c */
196 void get_src_version(const char *modname, char sum[], unsigned sumlen);
197 
198 /* from modpost.c */
199 char *read_text_file(const char *filename);
200 char *get_line(char **stringp);
201 
202 enum loglevel {
203 	LOG_WARN,
204 	LOG_ERROR,
205 	LOG_FATAL
206 };
207 
208 void modpost_log(enum loglevel loglevel, const char *fmt, ...);
209 
210 /*
211  * warn - show the given message, then let modpost continue running, still
212  *        allowing modpost to exit successfully. This should be used when
213  *        we still allow to generate vmlinux and modules.
214  *
215  * error - show the given message, then let modpost continue running, but fail
216  *         in the end. This should be used when we should stop building vmlinux
217  *         or modules, but we can continue running modpost to catch as many
218  *         issues as possible.
219  *
220  * fatal - show the given message, and bail out immediately. This should be
221  *         used when there is no point to continue running modpost.
222  */
223 #define warn(fmt, args...)	modpost_log(LOG_WARN, fmt, ##args)
224 #define error(fmt, args...)	modpost_log(LOG_ERROR, fmt, ##args)
225 #define fatal(fmt, args...)	modpost_log(LOG_FATAL, fmt, ##args)
226