xref: /linux/scripts/mod/modpost.h (revision 0be3ff0c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #include <stdio.h>
3 #include <stdlib.h>
4 #include <stdarg.h>
5 #include <string.h>
6 #include <sys/types.h>
7 #include <sys/stat.h>
8 #include <sys/mman.h>
9 #include <fcntl.h>
10 #include <unistd.h>
11 #include <elf.h>
12 
13 #include "elfconfig.h"
14 
15 /* On BSD-alike OSes elf.h defines these according to host's word size */
16 #undef ELF_ST_BIND
17 #undef ELF_ST_TYPE
18 #undef ELF_R_SYM
19 #undef ELF_R_TYPE
20 
21 #if KERNEL_ELFCLASS == ELFCLASS32
22 
23 #define Elf_Ehdr    Elf32_Ehdr
24 #define Elf_Shdr    Elf32_Shdr
25 #define Elf_Sym     Elf32_Sym
26 #define Elf_Addr    Elf32_Addr
27 #define Elf_Sword   Elf64_Sword
28 #define Elf_Section Elf32_Half
29 #define ELF_ST_BIND ELF32_ST_BIND
30 #define ELF_ST_TYPE ELF32_ST_TYPE
31 
32 #define Elf_Rel     Elf32_Rel
33 #define Elf_Rela    Elf32_Rela
34 #define ELF_R_SYM   ELF32_R_SYM
35 #define ELF_R_TYPE  ELF32_R_TYPE
36 #else
37 
38 #define Elf_Ehdr    Elf64_Ehdr
39 #define Elf_Shdr    Elf64_Shdr
40 #define Elf_Sym     Elf64_Sym
41 #define Elf_Addr    Elf64_Addr
42 #define Elf_Sword   Elf64_Sxword
43 #define Elf_Section Elf64_Half
44 #define ELF_ST_BIND ELF64_ST_BIND
45 #define ELF_ST_TYPE ELF64_ST_TYPE
46 
47 #define Elf_Rel     Elf64_Rel
48 #define Elf_Rela    Elf64_Rela
49 #define ELF_R_SYM   ELF64_R_SYM
50 #define ELF_R_TYPE  ELF64_R_TYPE
51 #endif
52 
53 /* The 64-bit MIPS ELF ABI uses an unusual reloc format. */
54 typedef struct
55 {
56 	Elf32_Word    r_sym;	/* Symbol index */
57 	unsigned char r_ssym;	/* Special symbol for 2nd relocation */
58 	unsigned char r_type3;	/* 3rd relocation type */
59 	unsigned char r_type2;	/* 2nd relocation type */
60 	unsigned char r_type1;	/* 1st relocation type */
61 } _Elf64_Mips_R_Info;
62 
63 typedef union
64 {
65 	Elf64_Xword		r_info_number;
66 	_Elf64_Mips_R_Info	r_info_fields;
67 } _Elf64_Mips_R_Info_union;
68 
69 #define ELF64_MIPS_R_SYM(i) \
70   ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym)
71 
72 #define ELF64_MIPS_R_TYPE(i) \
73   ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1)
74 
75 #if KERNEL_ELFDATA != HOST_ELFDATA
76 
77 static inline void __endian(const void *src, void *dest, unsigned int size)
78 {
79 	unsigned int i;
80 	for (i = 0; i < size; i++)
81 		((unsigned char*)dest)[i] = ((unsigned char*)src)[size - i-1];
82 }
83 
84 #define TO_NATIVE(x)						\
85 ({								\
86 	typeof(x) __x;						\
87 	__endian(&(x), &(__x), sizeof(__x));			\
88 	__x;							\
89 })
90 
91 #else /* endianness matches */
92 
93 #define TO_NATIVE(x) (x)
94 
95 #endif
96 
97 #define NOFAIL(ptr)   do_nofail((ptr), #ptr)
98 void *do_nofail(void *ptr, const char *expr);
99 
100 struct buffer {
101 	char *p;
102 	int pos;
103 	int size;
104 };
105 
106 void __attribute__((format(printf, 2, 3)))
107 buf_printf(struct buffer *buf, const char *fmt, ...);
108 
109 void
110 buf_write(struct buffer *buf, const char *s, int len);
111 
112 struct namespace_list {
113 	struct namespace_list *next;
114 	char namespace[];
115 };
116 
117 struct module {
118 	struct module *next;
119 	int gpl_compatible;
120 	struct symbol *unres;
121 	int from_dump;  /* 1 if module was loaded from *.symvers */
122 	int is_vmlinux;
123 	int seen;
124 	int has_init;
125 	int has_cleanup;
126 	struct buffer dev_table_buf;
127 	char	     srcversion[25];
128 	// Missing namespace dependencies
129 	struct namespace_list *missing_namespaces;
130 	// Actual imported namespaces
131 	struct namespace_list *imported_namespaces;
132 	char name[];
133 };
134 
135 struct elf_info {
136 	size_t size;
137 	Elf_Ehdr     *hdr;
138 	Elf_Shdr     *sechdrs;
139 	Elf_Sym      *symtab_start;
140 	Elf_Sym      *symtab_stop;
141 	Elf_Section  export_sec;
142 	Elf_Section  export_gpl_sec;
143 	char         *strtab;
144 	char	     *modinfo;
145 	unsigned int modinfo_len;
146 
147 	/* support for 32bit section numbers */
148 
149 	unsigned int num_sections; /* max_secindex + 1 */
150 	unsigned int secindex_strings;
151 	/* if Nth symbol table entry has .st_shndx = SHN_XINDEX,
152 	 * take shndx from symtab_shndx_start[N] instead */
153 	Elf32_Word   *symtab_shndx_start;
154 	Elf32_Word   *symtab_shndx_stop;
155 };
156 
157 static inline int is_shndx_special(unsigned int i)
158 {
159 	return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
160 }
161 
162 /*
163  * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
164  * the way to -256..-1, to avoid conflicting with real section
165  * indices.
166  */
167 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))
168 
169 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
170 static inline unsigned int get_secindex(const struct elf_info *info,
171 					const Elf_Sym *sym)
172 {
173 	if (is_shndx_special(sym->st_shndx))
174 		return SPECIAL(sym->st_shndx);
175 	if (sym->st_shndx != SHN_XINDEX)
176 		return sym->st_shndx;
177 	return info->symtab_shndx_start[sym - info->symtab_start];
178 }
179 
180 /* file2alias.c */
181 extern unsigned int cross_build;
182 void handle_moddevtable(struct module *mod, struct elf_info *info,
183 			Elf_Sym *sym, const char *symname);
184 void add_moddevtable(struct buffer *buf, struct module *mod);
185 
186 /* sumversion.c */
187 void get_src_version(const char *modname, char sum[], unsigned sumlen);
188 
189 /* from modpost.c */
190 char *read_text_file(const char *filename);
191 char *get_line(char **stringp);
192 
193 enum loglevel {
194 	LOG_WARN,
195 	LOG_ERROR,
196 	LOG_FATAL
197 };
198 
199 void modpost_log(enum loglevel loglevel, const char *fmt, ...);
200 
201 /*
202  * warn - show the given message, then let modpost continue running, still
203  *        allowing modpost to exit successfully. This should be used when
204  *        we still allow to generate vmlinux and modules.
205  *
206  * error - show the given message, then let modpost continue running, but fail
207  *         in the end. This should be used when we should stop building vmlinux
208  *         or modules, but we can continue running modpost to catch as many
209  *         issues as possible.
210  *
211  * fatal - show the given message, and bail out immediately. This should be
212  *         used when there is no point to continue running modpost.
213  */
214 #define warn(fmt, args...)	modpost_log(LOG_WARN, fmt, ##args)
215 #define error(fmt, args...)	modpost_log(LOG_ERROR, fmt, ##args)
216 #define fatal(fmt, args...)	modpost_log(LOG_FATAL, fmt, ##args)
217