scripts/mod/modpost.h

   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_unused_sec;
 143         Elf_Section  export_gpl_sec;
 144         Elf_Section  export_unused_gpl_sec;
 145         Elf_Section  export_gpl_future_sec;
 146         char         *strtab;
 147         char         *modinfo;
 148         unsigned int modinfo_len;
 149
 150         /* support for 32bit section numbers */
 151
 152         unsigned int num_sections; /* max_secindex + 1 */
 153         unsigned int secindex_strings;
 154         /* if Nth symbol table entry has .st_shndx = SHN_XINDEX,
 155          * take shndx from symtab_shndx_start[N] instead */
 156         Elf32_Word   *symtab_shndx_start;
 157         Elf32_Word   *symtab_shndx_stop;
 158 };
 159
 160 static inline int is_shndx_special(unsigned int i)
 161 {
 162         return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
 163 }
 164
 165 /*
 166  * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
 167  * the way to -256..-1, to avoid conflicting with real section
 168  * indices.
 169  */
 170 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))
 171
 172 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
 173 static inline unsigned int get_secindex(const struct elf_info *info,
 174                                         const Elf_Sym *sym)
 175 {
 176         if (is_shndx_special(sym->st_shndx))
 177                 return SPECIAL(sym->st_shndx);
 178         if (sym->st_shndx != SHN_XINDEX)
 179                 return sym->st_shndx;
 180         return info->symtab_shndx_start[sym - info->symtab_start];
 181 }
 182
 183 /* file2alias.c */
 184 extern unsigned int cross_build;
 185 void handle_moddevtable(struct module *mod, struct elf_info *info,
 186                         Elf_Sym *sym, const char *symname);
 187 void add_moddevtable(struct buffer *buf, struct module *mod);
 188
 189 /* sumversion.c */
 190 void get_src_version(const char *modname, char sum[], unsigned sumlen);
 191
 192 /* from modpost.c */
 193 char *read_text_file(const char *filename);
 194 char *get_line(char **stringp);
 195
 196 enum loglevel {
 197         LOG_WARN,
 198         LOG_ERROR,
 199         LOG_FATAL
 200 };
 201
 202 void modpost_log(enum loglevel loglevel, const char *fmt, ...);
 203
 204 /*
 205  * warn - show the given message, then let modpost continue running, still
 206  *        allowing modpost to exit successfully. This should be used when
 207  *        we still allow to generate vmlinux and modules.
 208  *
 209  * error - show the given message, then let modpost continue running, but fail
 210  *         in the end. This should be used when we should stop building vmlinux
 211  *         or modules, but we can continue running modpost to catch as many
 212  *         issues as possible.
 213  *
 214  * fatal - show the given message, and bail out immediately. This should be
 215  *         used when there is no point to continue running modpost.
 216  */
 217 #define warn(fmt, args...)      modpost_log(LOG_WARN, fmt, ##args)
 218 #define error(fmt, args...)     modpost_log(LOG_ERROR, fmt, ##args)
 219 #define fatal(fmt, args...)     modpost_log(LOG_FATAL, fmt, ##args)