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-rw-r--r--toys/other/readelf.c640
1 files changed, 640 insertions, 0 deletions
diff --git a/toys/other/readelf.c b/toys/other/readelf.c
new file mode 100644
index 00000000..45afd83a
--- /dev/null
+++ b/toys/other/readelf.c
@@ -0,0 +1,640 @@
+/* readelf.c - display information about ELF files.
+ *
+ * Copyright 2019 The Android Open Source Project
+ *
+ * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/nm.html
+
+USE_READELF(NEWTOY(readelf, "<1(dyn-syms)adehlnp:SsWx:", TOYFLAG_USR|TOYFLAG_BIN))
+
+config READELF
+ bool "readelf"
+ default y
+ help
+ usage: readelf [-adehlnSs] [-p SECTION] [-x SECTION] [file...]
+
+ Displays information about ELF files.
+
+ -a Equivalent to -dhlnSs
+ -d Show dynamic section
+ -e Headers (equivalent to -hlS)
+ -h Show ELF header
+ -l Show program headers
+ -n Show notes
+ -p S Dump strings found in named/numbered section
+ -S Show section headers
+ -s Show symbol tables (.dynsym and .symtab)
+ -x S Hex dump of named/numbered section
+
+ --dyn-syms Show just .dynsym symbol table
+*/
+
+#define FOR_readelf
+#include "toys.h"
+
+GLOBALS(
+ char *x, *p;
+
+ char *elf, *shstrtab, *f;
+ unsigned long long shoff, phoff, size, shstrtabsz;
+ int bits, endian, shnum, shentsize, phentsize;
+)
+
+// Section header.
+struct sh {
+ unsigned type, link, info;
+ unsigned long long flags, addr, offset, size, addralign, entsize;
+ char *name;
+};
+
+// Program header.
+struct ph {
+ unsigned type, flags;
+ unsigned long long offset, vaddr, paddr, filesz, memsz, align;
+};
+
+static long long elf_get(char **p, int len)
+{
+ long long result;
+
+ if (*p+len-TT.elf>TT.size)
+ perror_exit("Access off end: %ld[%d] of %lld\n", *p-TT.elf, len, TT.size);
+
+ result = ((TT.endian == 2) ? peek_be : peek_le)(*p, len);
+ *p += len;
+ return result;
+}
+
+static unsigned long long elf_long(char **p)
+{
+ return elf_get(p, 4*(TT.bits+1));
+}
+
+static unsigned elf_int(char **p)
+{
+ return elf_get(p, 4);
+}
+
+static unsigned short elf_short(char **p)
+{
+ return elf_get(p, 2);
+}
+
+static int get_sh(unsigned i, struct sh *s)
+{
+ char *shdr = TT.elf+TT.shoff+i*TT.shentsize;
+ unsigned name_offset;
+
+ if (i >= TT.shnum || shdr > TT.elf+TT.size-TT.shentsize) {
+ printf("No shdr %d\n", i);
+ return 0;
+ }
+
+ name_offset = elf_int(&shdr);
+ s->type = elf_int(&shdr);
+ s->flags = elf_long(&shdr);
+ s->addr = elf_long(&shdr);
+ s->offset = elf_long(&shdr);
+ s->size = elf_long(&shdr);
+ s->link = elf_int(&shdr);
+ s->info = elf_int(&shdr);
+ s->addralign = elf_long(&shdr);
+ s->entsize = elf_long(&shdr);
+
+ if (s->type != 8) {
+ if (s->offset>TT.size || s->size>TT.size || s->offset>TT.size-s->size) {
+ printf("Bad offset/size %llu/%llu for sh %d\n", s->offset, s->size, i);
+ return 0;
+ }
+ }
+
+ if (!TT.shstrtab) s->name = "?";
+ else {
+ s->name = TT.shstrtab + name_offset;
+ if (name_offset > TT.shstrtabsz || s->name >= TT.elf+TT.size) {
+ printf("Bad name for sh %d\n", i);
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+static int find_section(char *spec, struct sh *s)
+{
+ char *end;
+ unsigned i;
+
+ // Valid section number?
+ i = estrtol(spec, &end, 0);
+ if (!errno && !*end && i<TT.shnum) return get_sh(i, s);
+
+ // Search the section names.
+ for (i=0; i<TT.shnum; i++)
+ if (get_sh(i, s) && !strcmp(s->name, spec)) return 1;
+
+ error_msg("%s: no section '%s", TT.f, spec);
+ return 0;
+}
+
+static int get_ph(int i, struct ph *ph)
+{
+ char *phdr = TT.elf+TT.phoff+i*TT.phentsize;
+
+ if (phdr > TT.elf+TT.size-TT.phentsize) {
+ printf("Bad phdr %d\n", i);
+ return 0;
+ }
+
+ // Elf64_Phdr reordered fields.
+ ph->type = elf_int(&phdr);
+ if (TT.bits) {
+ ph->flags = elf_int(&phdr);
+ ph->offset = elf_long(&phdr);
+ ph->vaddr = elf_long(&phdr);
+ ph->paddr = elf_long(&phdr);
+ ph->filesz = elf_long(&phdr);
+ ph->memsz = elf_long(&phdr);
+ ph->align = elf_long(&phdr);
+ } else {
+ ph->offset = elf_int(&phdr);
+ ph->vaddr = elf_int(&phdr);
+ ph->paddr = elf_int(&phdr);
+ ph->filesz = elf_int(&phdr);
+ ph->memsz = elf_int(&phdr);
+ ph->flags = elf_int(&phdr);
+ ph->align = elf_int(&phdr);
+ }
+
+ if (ph->offset >= TT.size-ph->filesz) {
+ printf("phdr %d has bad offset/size %llu/%llu", i, ph->offset, ph->filesz);
+ return 0;
+ }
+
+ return 1;
+}
+
+#define MAP(...) __VA_ARGS__
+#define DECODER(name, values) \
+ static char *name(int type) { \
+ static char unknown[20]; \
+ struct {int v; char *s;} a[] = values; \
+ int i; \
+ \
+ for (i=0; i<ARRAY_LEN(a); i++) if (type==a[i].v) return a[i].s; \
+ sprintf(unknown, "0x%x", type); \
+ return unknown; \
+ }
+
+DECODER(dt_type, MAP({{0,"x(NULL)"},{1,"N(NEEDED)"},{2,"b(PLTRELSZ)"},
+ {3,"x(PLTGOT)"},{4,"x(HASH)"},{5,"x(STRTAB)"},{6,"x(SYMTAB)"},{7,"x(RELA)"},
+ {8,"b(RELASZ)"},{9,"b(RELAENT)"},{10,"b(STRSZ)"},{11,"b(SYMENT)"},
+ {12,"x(INIT)"},{13,"x(FINI)"},{14,"S(SONAME)"},{15,"R(RPATH)"},
+ {16,"x(SYMBOLIC)"},{17,"x(REL)"},{18,"b(RELSZ)"},{19,"b(RELENT)"},
+ {20,"P(PLTREL)"},{21,"x(DEBUG)"},{22,"x(TEXTREL)"},{23,"x(JMPREL)"},
+ {24,"d(BIND_NOW)"},{25,"x(INIT_ARRAY)"},{26,"x(FINI_ARRAY)"},
+ {27,"b(INIT_ARRAYSZ)"},{28,"b(FINI_ARRAYSZ)"},{29,"R(RUNPATH)"},
+ {30,"f(FLAGS)"},{32,"x(PREINIT_ARRAY)"},{33,"x(PREINIT_ARRAYSZ)"},
+ {35,"b(RELRSZ)"},{36,"x(RELR)"},{37,"b(RELRENT)"},
+ {0x6000000f,"x(ANDROID_REL)"},{0x60000010,"b(ANDROID_RELSZ)"},
+ {0x60000011,"x(ANDROID_RELA)"},{0x60000012,"b(ANDROID_RELASZ)"},
+ {0x6fffe000,"x(ANDROID_RELR)"},{0x6fffe001,"b(ANDROID_RELRSZ)"},
+ {0x6fffe003,"x(ANDROID_RELRENT)"},{0x6ffffef5,"x(GNU_HASH)"},
+ {0x6ffffef6,"x(TLSDESC_PLT)"},{0x6ffffef7,"x(TLSDESC_GOT)"},
+ {0x6ffffff0,"x(VERSYM)"},{0x6ffffff9,"d(RELACOUNT)"},
+ {0x6ffffffa,"d(RELCOUNT)"},{0x6ffffffb,"F(FLAGS_1)"},
+ {0x6ffffffc," (VERDEF)"},{0x6ffffffd,"d(VERDEFNUM)"},
+ {0x6ffffffe,"x(VERNEED)"},{0x6fffffff,"d(VERNEEDNUM)"}}))
+
+DECODER(et_type, MAP({{0,"NONE (None)"},{1,"REL (Relocatable file)"},
+ {2,"EXEC (Executable file)"},{3,"DYN (Shared object file)"},
+ {4,"CORE (Core file)"}}))
+
+DECODER(nt_type_core, MAP({{1,"NT_PRSTATUS"},{2,"NT_FPREGSET"},
+ {3,"NT_PRPSINFO"},{5,"NT_PLATFORM"},{6,"NT_AUXV"},
+ {0x46494c45,"NT_FILE"},{0x53494749,"NT_SIGINFO"}}))
+
+DECODER(nt_type_linux, MAP({{0x200,"NT_386_TLS"},{0x202, "NT_X86_XSTATE"},
+ {0x400,"NT_ARM_VFP"},{0x401,"NT_ARM_TLS"},{0x405,"NT_ARM_SVE"}}))
+
+DECODER(os_abi, MAP({{0,"UNIX - System V"}}))
+
+DECODER(ph_type, MAP({{0,"NULL"},{1,"LOAD"},{2,"DYNAMIC"},{3,"INTERP"},
+ {4,"NOTE"},{5,"SHLIB"},{6,"PHDR"},{7,"TLS"},{0x6474e550,"GNU_EH_FRAME"},
+ {0x6474e551,"GNU_STACK"},{0x6474e552,"GNU_RELRO"},{0x70000001,"EXIDX"}}))
+
+DECODER(sh_type, MAP({{0,"NULL"},{1,"PROGBITS"},{2,"SYMTAB"},{3,"STRTAB"},
+ {4,"RELA"},{5,"HASH"},{6,"DYNAMIC"},{7,"NOTE"},{8,"NOBITS"},{9,"REL"},
+ {10,"SHLIB"},{11,"DYNSYM"},{14,"INIT_ARRAY"},{15,"FINI_ARRAY"},
+ {16,"PREINIT_ARRAY"},{17,"GROUP"},{18,"SYMTAB_SHNDX"},{19,"RELR"},
+ {0x60000001,"ANDROID_REL"},{0x60000002,"ANDROID_RELA"},
+ {0x6fffff00,"ANDROID_RELR"},{0x6ffffff6,"GNU_HASH"},
+ {0x6ffffffd,"VERDEF"},{0x6ffffffe,"VERNEED"},
+ {0x6fffffff,"VERSYM"},{0x70000001,"ARM_EXIDX"},
+ {0x70000003,"ARM_ATTRIBUTES"}}))
+
+DECODER(stb_type, MAP({{0,"LOCAL"},{1,"GLOBAL"},{2,"WEAK"}}))
+
+DECODER(stt_type, MAP({{0,"NOTYPE"},{1,"OBJECT"},{2,"FUNC"},{3,"SECTION"},
+ {4,"FILE"},{5,"COMMON"},{6,"TLS"},{10,"GNU_IFUNC"}}))
+
+DECODER(stv_type, MAP({{0,"DEFAULT"},{1,"INTERNAL"},{2,"HIDDEN"},
+ {3,"PROTECTED"}}))
+
+static void show_symbols(struct sh *table, struct sh *strtab)
+{
+ char *symtab = TT.elf+table->offset, *ndx;
+ int numsym = table->size/(TT.bits ? 24 : 16), i;
+
+ if (!numsym) return;
+
+ xputc('\n');
+ printf("Symbol table '%s' contains %d entries:\n"
+ " Num: %*s Size Type Bind Vis Ndx Name\n",
+ table->name, numsym, 5+8*TT.bits, "Value");
+ for (i=0; i<numsym; i++) {
+ unsigned st_name = elf_int(&symtab), st_value, st_shndx, st_info, st_other;
+ unsigned long st_size;
+ char *name, buf[16];
+
+ // The various fields were moved around for 64-bit.
+ if (TT.bits) {
+ st_info = *symtab++;
+ st_other = *symtab++;
+ st_shndx = elf_short(&symtab);
+ st_value = elf_long(&symtab);
+ st_size = elf_long(&symtab);
+ } else {
+ st_value = elf_int(&symtab);
+ st_size = elf_int(&symtab);
+ st_info = *symtab++;
+ st_other = *symtab++;
+ st_shndx = elf_short(&symtab);
+ }
+
+ // TODO: why do we trust name to be null terminated?
+ name = TT.elf + strtab->offset + st_name;
+ if (name >= TT.elf+TT.size) name = "???";
+
+ if (!st_shndx) ndx = "UND";
+ else if (st_shndx==0xfff1) ndx = "ABS";
+ else sprintf(ndx = buf, "%d", st_shndx);
+
+ // TODO: look up and show any symbol versions with @ or @@.
+
+ printf("%6d: %0*x %5lu %-7s %-6s %-9s%3s %s\n", i, 8*(TT.bits+1),
+ st_value, st_size, stt_type(st_info & 0xf), stb_type(st_info >> 4),
+ stv_type(st_other & 3), ndx, name);
+ }
+}
+
+static int notematch(int namesz, char **p, char *expected)
+{
+ if (namesz!=strlen(expected)+1 || strcmp(*p, expected)) return 0;
+ *p += namesz;
+
+ return 1;
+}
+
+static void show_notes(unsigned long offset, unsigned long size)
+{
+ char *note = TT.elf + offset;
+
+ if (size > TT.size || offset > TT.size-size) {
+ printf("Bad note bounds %lu/%lu\n", offset, size);
+
+ return;
+ }
+
+ printf(" %-20s%11s\tDescription\n", "Owner", "Data size");
+ while (note < TT.elf+offset+size) {
+ char *p = note, *desc;
+ unsigned namesz=elf_int(&p), descsz=elf_int(&p), type=elf_int(&p), j=0;
+
+ if (namesz > size || descsz > size)
+ return error_msg("%s: bad note @%lu", TT.f, offset);
+ printf(" %-20.*s 0x%08x\t", namesz, p, descsz);
+ if (notematch(namesz, &p, "GNU")) {
+ if (type == 1) {
+ printf("NT_GNU_ABI_TAG\tOS: %s, ABI: %u.%u.%u",
+ !elf_int(&p)?"Linux":"?", elf_int(&p), elf_int(&p), elf_int(&p)), j=1;
+ } else if (type == 3) {
+// TODO should this set j=1?
+ printf("NT_GNU_BUILD_ID\t");
+ for (;j<descsz;j++) printf("%02x", *p++);
+ } else if (type == 4) {
+ printf("NT_GNU_GOLD_VERSION\t%.*s", descsz, p), j=1;
+ } else p -= 4;
+ } else if (notematch(namesz, &p, "Android")) {
+ if (type == 1) {
+ printf("NT_VERSION\tAPI level %u", elf_int(&p)), j=1;
+ if (descsz>=132) printf(", NDK %.64s (%.64s)", p, p+64);
+ } else p -= 8;
+ } else if (notematch(namesz, &p, "CORE")) {
+ if (*(desc = nt_type_core(type)) != '0') printf("%s", desc), j=1;
+// TODO else p -= 5?
+ } else if (notematch(namesz, &p, "LINUX")) {
+ if (*(desc = nt_type_linux(type)) != '0') printf("%s", desc), j=1;
+// TODO else p -= 6?
+ }
+
+ // If we didn't do custom output above, show a hex dump.
+ if (!j) {
+ printf("0x%x\t", type);
+ for (;j<descsz;j++) printf("%c%02x", j ? ' ' : '\t', *p++/*note[16+j]*/);
+ }
+ xputc('\n');
+ note += 3*4 + ((namesz+3)&~3) + ((descsz+3)&~3);
+ }
+}
+
+static void scan_elf()
+{
+ struct sh dynamic = {}, dynstr = {}, dynsym = {}, shstr = {}, strtab = {},
+ symtab = {}, s;
+ struct ph ph;
+ char *hdr = TT.elf;
+ int type, machine, version, flags, entry, ehsize, phnum, shstrndx, i, j, w;
+
+ if (TT.size < 45 || memcmp(hdr, "\177ELF", 4))
+ return error_msg("%s: not ELF", TT.f);
+
+ TT.bits = hdr[4] - 1;
+ TT.endian = hdr[5];
+ if (TT.bits<0 || TT.bits>1 || TT.endian<1 || TT.endian>2 || hdr[6]!=1)
+ return error_msg("%s: bad ELF", TT.f);
+
+ hdr += 16; // EI_NIDENT
+ type = elf_short(&hdr);
+ machine = elf_short(&hdr);
+ version = elf_int(&hdr);
+ entry = elf_long(&hdr);
+ TT.phoff = elf_long(&hdr);
+ TT.shoff = elf_long(&hdr);
+ flags = elf_int(&hdr);
+ ehsize = elf_short(&hdr);
+ TT.phentsize = elf_short(&hdr);
+ phnum = elf_short(&hdr);
+ TT.shentsize = elf_short(&hdr);
+ TT.shnum = elf_short(&hdr);
+ shstrndx = elf_short(&hdr);
+
+ if (toys.optc > 1) printf("\nFile: %s\n", TT.f);
+
+ if (FLAG(h)) {
+ printf("ELF Header:\n");
+ printf(" Magic: ");
+ for (i=0; i<16; i++) printf("%02x%c", TT.elf[i], (i==15) ? '\n' : ' ');
+ printf(" Class: ELF%d\n", TT.bits?64:32);
+ printf(" Data: 2's complement, %s endian\n",
+ (TT.endian==2)?"big":"little");
+ printf(" Version: 1 (current)\n");
+ printf(" OS/ABI: %s\n", os_abi(TT.elf[7]));
+ printf(" ABI Version: %d\n", TT.elf[8]);
+ printf(" Type: %s\n", et_type(type));
+ printf(" Machine: %s\n", elf_arch_name(machine));
+ printf(" Version: 0x%x\n", version);
+ printf(" Entry point address: 0x%x\n", entry);
+ printf(" Start of program headers: %llu (bytes into file)\n",
+ TT.phoff);
+ printf(" Start of section headers: %llu (bytes into file)\n",
+ TT.shoff);
+ printf(" Flags: 0x%x\n", flags);
+ printf(" Size of this header: %d (bytes)\n", ehsize);
+ printf(" Size of program headers: %d (bytes)\n", TT.phentsize);
+ printf(" Number of program headers: %d\n", phnum);
+ printf(" Size of section headers: %d (bytes)\n", TT.shentsize);
+ printf(" Number of section headers: %d\n", TT.shnum);
+ printf(" Section header string table index: %d\n", shstrndx);
+ }
+ if (TT.phoff > TT.size) return error_msg("%s: bad phoff", TT.f);
+ if (TT.shoff > TT.size) return error_msg("%s: bad shoff", TT.f);
+
+ // Set up the section header string table so we can use section header names.
+ // Core files have shstrndx == 0.
+ TT.shstrtab = 0;
+ TT.shstrtabsz = 0;
+ if (shstrndx) {
+ if (!get_sh(shstrndx, &shstr) || shstr.type != 3 /*SHT_STRTAB*/)
+ return error_msg("%s: bad shstrndx", TT.f);
+ TT.shstrtab = TT.elf+shstr.offset;
+ TT.shstrtabsz = shstr.size;
+ }
+
+ w = 8<<TT.bits;
+ if (FLAG(S)) {
+ if (!TT.shnum) printf("\nThere are no sections in this file.\n");
+ else {
+ if (!FLAG(h))
+ printf("There are %d section headers, starting at offset %#llx:\n",
+ TT.shnum, TT.shoff);
+ printf("\nSection Headers:\n"
+ " [Nr] %-17s %-15s %-*s %-6s %-6s ES Flg Lk Inf Al\n",
+ "Name", "Type", w, "Address", "Off", "Size");
+ }
+ }
+ // We need to iterate through the section headers even if we're not
+ // dumping them, to find specific sections.
+ for (i=0; i<TT.shnum; i++) {
+ if (!get_sh(i, &s)) continue;
+ if (s.type == 2 /*SHT_SYMTAB*/) symtab = s;
+ else if (s.type == 6 /*SHT_DYNAMIC*/) dynamic = s;
+ else if (s.type == 11 /*SHT_DYNSYM*/) dynsym = s;
+ else if (s.type == 3 /*SHT_STRTAB*/) {
+ if (!strcmp(s.name, ".strtab")) strtab = s;
+ else if (!strcmp(s.name, ".dynstr")) dynstr = s;
+ }
+
+ if (FLAG(S)) {
+ char sh_flags[12] = {}, *p = sh_flags;
+
+ for (j=0; j<12; j++) if (s.flags&(1<<j)) *p++ = "WAXxMSILOTC"[j];
+ printf(" [%2d] %-17s %-15s %0*llx %06llx %06llx %02llx %3s %2d %2d %2lld\n",
+ i, s.name, sh_type(s.type), w, s.addr, s.offset, s.size,
+ s.entsize, sh_flags, s.link, s.info, s.addralign);
+ }
+ }
+ if (FLAG(S) && TT.shnum)
+ printf("Key:\n (W)rite, (A)lloc, e(X)ecute, (M)erge, (S)trings, (I)nfo\n"
+ " (L)ink order, (O)S, (G)roup, (T)LS, (C)ompressed, x=unknown\n");
+
+ if (FLAG(l)) {
+ xputc('\n');
+ if (!phnum) printf("There are no program headers in this file.\n");
+ else {
+ if (!FLAG(h))
+ printf("Elf file type is %s\nEntry point %#x\n"
+ "There are %d program headers, starting at offset %lld\n\n",
+ et_type(type), entry, phnum, TT.phoff);
+ printf("Program Headers:\n"
+ " %-14s %-8s %-*s %-*s %-7s %-7s Flg Align\n", "Type",
+ "Offset", w, "VirtAddr", w, "PhysAddr", "FileSiz", "MemSiz");
+ for (i = 0; i<phnum; i++) {
+ if (!get_ph(i, &ph)) continue;
+ printf(" %-14s 0x%06llx 0x%0*llx 0x%0*llx 0x%05llx 0x%05llx %c%c%c %#llx\n",
+ ph_type(ph.type), ph.offset, w, ph.vaddr, w, ph.paddr,
+ ph.filesz, ph.memsz, (ph.flags&4)?'R':' ', (ph.flags&2)?'W':' ',
+ (ph.flags&1)?'E':' ', ph.align);
+ if (ph.type == 3 /*PH_INTERP*/ && ph.filesz<TT.size &&
+ ph.offset<TT.size && ph.filesz - 1 < TT.size - ph.offset) {
+// TODO: ph.filesz of 0 prints unlimited length string
+ printf(" [Requesting program interpreter: %*s]\n",
+ (int) ph.filesz-1, TT.elf+ph.offset);
+ }
+ }
+
+ printf("\n Section to Segment mapping:\n Segment Sections...\n");
+ for (i=0; i<phnum; i++) {
+ if (!get_ph(i, &ph)) continue;
+ printf(" %02d ", i);
+ for (j=0; j<TT.shnum; j++) {
+ if (!get_sh(j, &s)) continue;
+ if (!*s.name) continue;
+ if (s.offset >= ph.offset && s.offset+s.size <= ph.offset+ph.filesz)
+ printf("%s ", s.name);
+ }
+ xputc('\n');
+ }
+ }
+ }
+
+ // binutils ld emits a bunch of extra DT_NULL entries, so binutils readelf
+ // uses two passes here! We just tell the truth, which matches -h.
+ if (FLAG(d)) {
+ char *dyn = TT.elf+dynamic.offset, *end = dyn+dynamic.size;
+
+ xputc('\n');
+ if (!dynamic.size) printf("There is no dynamic section in this file.\n");
+ else if (!dynamic.entsize) printf("Bad dynamic entry size 0!\n");
+ else {
+ printf("Dynamic section at offset 0x%llx contains %lld entries:\n"
+ " %-*s %-20s %s\n", dynamic.offset, dynamic.size/dynamic.entsize,
+ w+2, "Tag", "Type", "Name/Value");
+ while (dyn < end) {
+ unsigned long long tag = elf_long(&dyn), val = elf_long(&dyn);
+ char *type = dt_type(tag);
+
+ printf(" 0x%0*llx %-20s ", w, tag, type+(*type!='0'));
+ if (*type == 'd') printf("%lld\n", val);
+ else if (*type == 'b') printf("%lld (bytes)\n", val);
+// TODO: trusting this %s to be null terminated
+ else if (*type == 's') printf("%s\n", TT.elf+dynstr.offset+val);
+ else if (*type == 'f' || *type == 'F') {
+ struct bitname { int bit; char *s; }
+ df_names[] = {{0, "ORIGIN"},{1,"SYMBOLIC"},{2,"TEXTREL"},
+ {3,"BIND_NOW"},{4,"STATIC_TLS"},{}},
+ df_1_names[]={{0,"NOW"},{1,"GLOBAL"},{2,"GROUP"},{3,"NODELETE"},
+ {5,"INITFIRST"},{27,"PIE"},{}},
+ *names = *type == 'f' ? df_names : df_1_names;
+ int mask;
+
+ if (*type == 'F') printf("Flags: ");
+ for (j=0; names[j].s; j++)
+ if (val & (mask=(1<<names[j].bit)))
+ printf("%s%s", names[j].s, (val &= ~mask) ? " " : "");
+ if (val) printf("0x%llx", val);
+ xputc('\n');
+ } else if (*type == 'N' || *type == 'R' || *type == 'S') {
+ char *s = TT.elf+dynstr.offset+val;
+
+ if (dynstr.offset>TT.size || val>TT.size || dynstr.offset>TT.size-val)
+ s = "???";
+ printf("%s: [%s]\n", *type=='N' ? "Shared library" :
+ (*type=='R' ? "Library runpath" : "Library soname"), s);
+ } else if (*type == 'P') {
+ j = strlen(type = dt_type(val));
+ if (*type != '0') type += 2, j -= 3;
+ printf("%*.*s\n", j, j, type);
+ } else printf("0x%llx\n", val);
+ }
+ }
+ }
+
+ if (FLAG(dyn_syms)) show_symbols(&dynsym, &dynstr);
+ if (FLAG(s)) show_symbols(&symtab, &strtab);
+
+ if (FLAG(n)) {
+ int found = 0;
+
+ for (i=0; i<TT.shnum; i++) {
+ if (!get_sh(i, &s)) continue;
+ if (s.type == 7 /*SHT_NOTE*/) {
+ printf("\nDisplaying notes found in: %s\n", s.name);
+ show_notes(s.offset, s.size);
+ found = 1;
+ }
+ }
+ for (i=0; !found && i<phnum; i++) {
+ if (!get_ph(i, &ph)) continue;
+ if (ph.type == 4 /*PT_NOTE*/) {
+ printf("\n"
+ "Displaying notes found at file offset 0x%llx with length 0x%llx:\n",
+ ph.offset, ph.filesz);
+ show_notes(ph.offset, ph.filesz);
+ }
+ }
+ }
+
+ if (FLAG(x) && find_section(TT.x, &s)) {
+ char *p = TT.elf+s.offset;
+ long offset = 0;
+
+ printf("\nHex dump of section '%s':\n", s.name);
+ while (offset < s.size) {
+ int space = 2*16 + 16/4;
+
+ printf(" 0x%08lx ", offset);
+ for (i=0; i<16 && offset < s.size; offset++)
+ space -= printf("%02x%s", *p++, " "+!!(++i%4));
+ printf("%*s", space, "");
+ for (p -= i; i; i--, p++) putchar((*p>=' ' && *p<='~') ? *p : '.');
+ xputc('\n');
+ }
+ xputc('\n');
+ }
+
+ if (FLAG(p) && find_section(TT.p, &s)) {
+ char *begin = TT.elf+s.offset, *end = begin + s.size, *p = begin;
+ int any = 0;
+
+ printf("\nString dump of section '%s':\n", s.name);
+ for (; p < end; p++) {
+ if (isprint(*p)) {
+ printf(" [%6tx] ", p-begin);
+ while (p < end && isprint(*p)) putchar(*p++);
+ xputc('\n');
+ any=1;
+ }
+ }
+ if (!any) printf(" No strings found in this section.\n");
+ xputc('\n');
+ }
+}
+
+void readelf_main(void)
+{
+ char **arg;
+ int all = FLAG_d|FLAG_h|FLAG_l|FLAG_n|FLAG_S|FLAG_s|FLAG_dyn_syms;
+
+ if (FLAG(a)) toys.optflags |= all;
+ if (FLAG(e)) toys.optflags |= FLAG_h|FLAG_l|FLAG_S;
+ if (FLAG(s)) toys.optflags |= FLAG_dyn_syms;
+ if (!(toys.optflags & (all|FLAG_p|FLAG_x))) help_exit("needs a flag");
+
+ for (arg = toys.optargs; *arg; arg++) {
+ int fd = open(TT.f = *arg, O_RDONLY);
+ struct stat sb;
+
+ if (fd == -1) perror_msg("%s", TT.f);
+ else {
+ if (fstat(fd, &sb)) perror_msg("%s", TT.f);
+ else if (!sb.st_size) error_msg("%s: empty", TT.f);
+ else if (!S_ISREG(sb.st_mode)) error_msg("%s: not a regular file",TT.f);
+ else {
+ TT.elf = xmmap(0, TT.size=sb.st_size, PROT_READ, MAP_SHARED, fd, 0);
+ scan_elf();
+ munmap(TT.elf, TT.size);
+ }
+ close(fd);
+ }
+ }
+}