1 /* $NetBSD: exec_sub.c,v 1.6 2009/03/14 21:04:17 dsl Exp $ */ 2 3 #include <sys/cdefs.h> 4 5 #include "execkern.h" 6 #include <a.out.h> 7 #include <sys/param.h> 8 9 #ifdef BOOT 10 void B_PRINT(const unsigned char *p); 11 #endif 12 13 static inline void bzero4(void *ptr, size_t siz); 14 static void xk_aout(struct execkern_arg *xarg, struct exec *hdr); 15 static void xk_elf(struct execkern_arg *xarg, Elf32_Ehdr *hdr); 16 17 #ifdef LOADBSD 18 static void DPRINT_SEC(const char *ident, 19 const struct execkern_section *sec); 20 extern int opt_v; 21 extern const char *kernel_fn; 22 23 static void 24 DPRINT_SEC(const char *ident, const struct execkern_section *sec) 25 { 26 27 if (opt_v) 28 xwarnx("section (%s): img %p, sz %d, pad %d", ident, 29 sec->sec_image, sec->sec_size, sec->sec_pad); 30 } 31 32 #define ERRX(arg) xerrx arg 33 34 #else 35 #define DPRINT_SEC(ident, sec) /**/ 36 #define ERRX(arg) return 1 37 #endif 38 39 /* 40 * This code is size-hacked version of 41 * 42 * sec->sec_image = (image); 43 * sec->sec_size = (size); 44 * sec->sec_pad = (pad); 45 * DPRINT_SEC((ident), sec); 46 * sec++; 47 */ 48 #define SECTION(sec, ident, image, size, pad) \ 49 do { \ 50 u_long *wp = (void *) sec; \ 51 *(void **)wp++ = (image); \ 52 *wp++ = (size); \ 53 *wp++ = (pad); \ 54 DPRINT_SEC((ident), sec); \ 55 sec = (void *) wp; \ 56 } while (0) 57 58 #define SECTION_NOPAD(sec, ident, image, size) \ 59 SECTION(sec, (ident), (image), (size), 0) 60 61 static inline void 62 bzero4(void *ptr, size_t siz) 63 { 64 u_long *p; 65 u_short s; 66 67 p = ptr; 68 s = siz >> 2; 69 70 while (s--) 71 *p++ = 0; 72 } 73 74 /* 75 * fill in loading information from an a.out executable 76 */ 77 static void 78 xk_aout(struct execkern_arg *xarg, struct exec *hdr) 79 { 80 unsigned u; 81 char *s; 82 struct execkern_section *sec; 83 84 xarg->entry_addr = hdr->a_entry; 85 sec = xarg->sec; 86 87 /* text section and padding between data section */ 88 s = (void *) (hdr + 1); 89 SECTION(sec, "text", s, hdr->a_text, -hdr->a_text & (AOUT_LDPGSZ-1)); 90 91 /* data and bss sections */ 92 s += hdr->a_text; 93 SECTION(sec, "data/bss", s, hdr->a_data, hdr->a_bss); 94 95 /* size of symbol table */ 96 SECTION_NOPAD(sec, "symtab size", &sec[1].sec_size, sizeof(u_long)); 97 98 /* symbol table section */ 99 s += hdr->a_data; 100 SECTION_NOPAD(sec, "symbol", s, u = hdr->a_syms); 101 102 /* string table section */ 103 if (u) { 104 #ifdef LOADBSD 105 if (opt_v) 106 xwarnx("symbol table found"); 107 #endif 108 s += u; 109 SECTION_NOPAD(sec, "string", s, *(u_long *) s); 110 } 111 } 112 113 /* 114 * fill in loading information from an ELF executable 115 */ 116 static void 117 xk_elf(struct execkern_arg *xarg, Elf32_Ehdr *hdr) 118 { 119 char *top = (void *) hdr; 120 struct execkern_section *sec; 121 Elf32_Phdr *ph; 122 Elf32_Shdr *sh, *sym, *str, *stab, *shstr; 123 const char *shstrtab, *shname; 124 unsigned u, dpos, pd; 125 const char *const shstrtab_new = SHSTRTAB_FAKE; 126 127 xarg->entry_addr = hdr->e_entry; 128 129 /* 130 * text, data, bss 131 */ 132 ph = (void *) (top + hdr->e_phoff); 133 xarg->load_addr = ph->p_vaddr; 134 135 sec = xarg->sec; 136 sec->sec_image = top + ph->p_offset; 137 sec->sec_size = ph->p_filesz; 138 139 if (hdr->e_phnum != 1) { 140 sec->sec_pad = ph[1].p_vaddr - (ph->p_vaddr + ph->p_filesz); 141 DPRINT_SEC("program (text)", sec); 142 sec++; 143 ph++; 144 sec->sec_image = top + ph->p_offset; 145 sec->sec_size = ph->p_filesz; 146 } 147 148 sec->sec_pad = ph->p_memsz - ph->p_filesz; 149 DPRINT_SEC("program (data/bss)", sec); 150 sec++; 151 152 /* 153 * symbol size 154 */ 155 xarg->elfsymsiz = 0; /* no symbol */ 156 SECTION_NOPAD(sec, "symtab size", &xarg->elfsymsiz, sizeof(int)); 157 158 /* 159 * ELF header 160 */ 161 xarg->ehdr = *hdr; 162 xarg->ehdr.e_shstrndx = 0; /* .shstrtab will be the 1st section */ 163 SECTION_NOPAD(sec, "ELF header", &xarg->ehdr, sizeof(Elf32_Ehdr)); 164 165 sh = (void *) (top + hdr->e_shoff); /* section header */ 166 shstr = sh + hdr->e_shstrndx; /* .shstrtab */ 167 shstrtab = top + shstr->sh_offset; 168 169 sym = str = stab = 0; 170 for (u = 0; sh++, ++u < hdr->e_shnum; ) { 171 shname = shstrtab + sh->sh_name; 172 if (!strcmp(shname, shstrtab_new + SHNAME_OFF_SYMTAB)) 173 sym = sh; /* .symtab */ 174 if (!strcmp(shname, shstrtab_new + SHNAME_OFF_STRTAB)) 175 str = sh; /* .strtab */ 176 if (!strcmp(shname, shstrtab_new + SHNAME_OFF_STAB)) 177 stab = sh; /* .stab */ 178 } 179 180 if (shstr == 0 || sym == 0 || str == 0) 181 xarg->ehdr.e_shnum = 0; /* no symbol */ 182 else { 183 #ifdef LOADBSD 184 if (opt_v) { 185 xwarnx("symbol table found"); 186 if (stab) 187 xwarnx("debugging information found"); 188 } 189 #endif 190 xarg->elfsymsiz = 1; /* has symbol */ 191 xarg->ehdr.e_shnum = 3; 192 xarg->ehdr.e_shoff = sizeof(Elf32_Ehdr); 193 194 SECTION_NOPAD(sec, "section header (shstrtab)", 195 shstr, sizeof(Elf32_Shdr)); 196 197 SECTION_NOPAD(sec, "section header (symbol)", 198 sym, sizeof(Elf32_Shdr)); 199 200 SECTION_NOPAD(sec, "section header (string)", 201 str, sizeof(Elf32_Shdr)); 202 203 dpos = sizeof(Elf32_Ehdr) + sizeof(Elf32_Shdr) * 3; 204 u = SIZE_SHSTRTAB_FAKE; 205 206 if (stab) { 207 xarg->ehdr.e_shnum++; 208 SECTION_NOPAD(sec, "section header (stab)", 209 stab, sizeof(Elf32_Shdr)); 210 dpos += sizeof(Elf32_Shdr); 211 u = SIZE_SHSTRTAB_FAKE_WITH_STAB; 212 } 213 214 /* new .shstrtab section */ 215 memcpy(xarg->shstrtab_fake, shstrtab_new, u); 216 /* 217 * DDB requires symtab be aligned. 218 */ 219 pd = -u & ALIGNBYTES; 220 SECTION(sec, "shstrtab", &xarg->shstrtab_fake, u, pd); 221 shstr->sh_name = SHNAME_OFF_SHSTRTAB; 222 shstr->sh_offset = dpos; 223 dpos += u + pd; 224 225 SECTION_NOPAD(sec, "symtab", 226 top + sym->sh_offset, sym->sh_size); 227 sym->sh_name = SHNAME_OFF_SYMTAB; 228 sym->sh_offset = dpos; 229 dpos += sym->sh_size; 230 231 SECTION_NOPAD(sec, "strtab", 232 top + str->sh_offset, str->sh_size); 233 str->sh_name = SHNAME_OFF_STRTAB; 234 str->sh_offset = dpos; 235 dpos += str->sh_size; 236 237 if (stab) { 238 SECTION_NOPAD(sec, "stab", 239 top + stab->sh_offset, stab->sh_size); 240 stab->sh_name = SHNAME_OFF_STAB; 241 stab->sh_offset = dpos; 242 } 243 } 244 } 245 246 247 int 248 xk_load(struct execkern_arg *xarg, void *buf, u_long loadaddr) 249 /* loadaddr: for a.out */ 250 { 251 struct exec *ahdr; 252 Elf32_Ehdr *ehdr; 253 unsigned u; 254 255 /* Unused section entries should be cleared to zero. */ 256 bzero4(xarg->sec, sizeof xarg->sec); 257 258 xarg->load_addr = loadaddr; 259 260 /* 261 * check exec header 262 */ 263 ahdr = buf; 264 ehdr = buf; 265 266 if (N_GETMAGIC(*ahdr) == NMAGIC) { 267 /* 268 * this is an a.out 269 */ 270 #ifdef LOADBSD 271 if (opt_v) 272 xwarnx("%s: is an a.out", kernel_fn); 273 #endif 274 #ifdef BOOT 275 B_PRINT("This is an a.out\r\n"); 276 #endif 277 278 if ((u = N_GETMID(*ahdr)) != MID_M68K) 279 ERRX((1, "%s: Wrong architecture (mid %u)", 280 kernel_fn, u)); 281 282 /* 283 * fill in loading information 284 */ 285 xk_aout(xarg, ahdr); 286 287 } else { 288 289 /* 290 * check ELF header 291 */ 292 if (*(u_int32_t *)&ehdr->e_ident[EI_MAG0] != 293 (ELFMAG0<<24 | ELFMAG1<<16 | ELFMAG2<<8 | ELFMAG3) || 294 *(u_int16_t *)&ehdr->e_ident[EI_CLASS] != 295 (ELFCLASS32 << 8 | ELFDATA2MSB)) 296 ERRX((1, "%s: Not an NMAGIC a.out or a 32bit BE ELF", 297 kernel_fn)); 298 299 /* 300 * this is an ELF 301 */ 302 #ifdef LOADBSD 303 if (opt_v) 304 xwarnx("%s: is an ELF", kernel_fn); 305 #endif 306 #ifdef BOOT 307 B_PRINT("This is an ELF\r\n"); 308 #endif 309 310 if (ehdr->e_ident[EI_VERSION] != EV_CURRENT || 311 ehdr->e_version != EV_CURRENT) 312 ERRX((1, "%s: Unsupported ELF version", kernel_fn)); 313 314 if ((u = ehdr->e_machine) != EM_68K) 315 ERRX((1, "%s: Wrong architecture (mid %u)", 316 kernel_fn, u)); 317 if (ehdr->e_type != ET_EXEC) 318 ERRX((1, "%s: Not an executable", kernel_fn)); 319 if ((u = ehdr->e_phnum) != 1 && u != 2) 320 ERRX((1, "%s: Wrong number (%u) of loading sections", 321 kernel_fn, u)); 322 323 /* 324 * fill in loading information 325 */ 326 xk_elf(xarg, ehdr); 327 } 328 329 return 0; 330 } 331