/* * Copyright (c) Christos Zoulas 2003. * All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice immediately at the beginning of the file, without modification, * this list of conditions, and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "file.h" #ifndef lint FILE_RCSID("@(#)$File: readelf.c,v 1.131 2017/02/10 18:14:01 christos Exp $") #endif #ifdef BUILTIN_ELF #include #include #include #ifdef HAVE_UNISTD_H #include #endif #include "readelf.h" #include "magic.h" #ifdef ELFCORE private int dophn_core(struct magic_set *, int, int, int, off_t, int, size_t, off_t, int *, uint16_t *); #endif private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t, off_t, int, int *, uint16_t *); private int doshn(struct magic_set *, int, int, int, off_t, int, size_t, off_t, int, int, int *, uint16_t *); private size_t donote(struct magic_set *, void *, size_t, size_t, int, int, size_t, int *, uint16_t *, int, off_t, int, off_t); #define ELF_ALIGN(a) ((((a) + align - 1) / align) * align) #define isquote(c) (strchr("'\"`", (c)) != NULL) private uint16_t getu16(int, uint16_t); private uint32_t getu32(int, uint32_t); private uint64_t getu64(int, uint64_t); #define MAX_PHNUM 128 #define MAX_SHNUM 32768 #define SIZE_UNKNOWN ((off_t)-1) private int toomany(struct magic_set *ms, const char *name, uint16_t num) { if (file_printf(ms, ", too many %s (%u)", name, num ) == -1) return -1; return 0; } private uint16_t getu16(int swap, uint16_t value) { union { uint16_t ui; char c[2]; } retval, tmpval; if (swap) { tmpval.ui = value; retval.c[0] = tmpval.c[1]; retval.c[1] = tmpval.c[0]; return retval.ui; } else return value; } private uint32_t getu32(int swap, uint32_t value) { union { uint32_t ui; char c[4]; } retval, tmpval; if (swap) { tmpval.ui = value; retval.c[0] = tmpval.c[3]; retval.c[1] = tmpval.c[2]; retval.c[2] = tmpval.c[1]; retval.c[3] = tmpval.c[0]; return retval.ui; } else return value; } private uint64_t getu64(int swap, uint64_t value) { union { uint64_t ui; char c[8]; } retval, tmpval; if (swap) { tmpval.ui = value; retval.c[0] = tmpval.c[7]; retval.c[1] = tmpval.c[6]; retval.c[2] = tmpval.c[5]; retval.c[3] = tmpval.c[4]; retval.c[4] = tmpval.c[3]; retval.c[5] = tmpval.c[2]; retval.c[6] = tmpval.c[1]; retval.c[7] = tmpval.c[0]; return retval.ui; } else return value; } #define elf_getu16(swap, value) getu16(swap, value) #define elf_getu32(swap, value) getu32(swap, value) #define elf_getu64(swap, value) getu64(swap, value) #define xsh_addr (clazz == ELFCLASS32 \ ? (void *)&sh32 \ : (void *)&sh64) #define xsh_sizeof (clazz == ELFCLASS32 \ ? sizeof(sh32) \ : sizeof(sh64)) #define xsh_size (size_t)(clazz == ELFCLASS32 \ ? elf_getu32(swap, sh32.sh_size) \ : elf_getu64(swap, sh64.sh_size)) #define xsh_offset (off_t)(clazz == ELFCLASS32 \ ? elf_getu32(swap, sh32.sh_offset) \ : elf_getu64(swap, sh64.sh_offset)) #define xsh_type (clazz == ELFCLASS32 \ ? elf_getu32(swap, sh32.sh_type) \ : elf_getu32(swap, sh64.sh_type)) #define xsh_name (clazz == ELFCLASS32 \ ? elf_getu32(swap, sh32.sh_name) \ : elf_getu32(swap, sh64.sh_name)) #define xph_addr (clazz == ELFCLASS32 \ ? (void *) &ph32 \ : (void *) &ph64) #define xph_sizeof (clazz == ELFCLASS32 \ ? sizeof(ph32) \ : sizeof(ph64)) #define xph_type (clazz == ELFCLASS32 \ ? elf_getu32(swap, ph32.p_type) \ : elf_getu32(swap, ph64.p_type)) #define xph_offset (off_t)(clazz == ELFCLASS32 \ ? elf_getu32(swap, ph32.p_offset) \ : elf_getu64(swap, ph64.p_offset)) #define xph_align (size_t)((clazz == ELFCLASS32 \ ? (off_t) (ph32.p_align ? \ elf_getu32(swap, ph32.p_align) : 4) \ : (off_t) (ph64.p_align ? \ elf_getu64(swap, ph64.p_align) : 4))) #define xph_vaddr (size_t)((clazz == ELFCLASS32 \ ? (off_t) (ph32.p_vaddr ? \ elf_getu32(swap, ph32.p_vaddr) : 4) \ : (off_t) (ph64.p_vaddr ? \ elf_getu64(swap, ph64.p_vaddr) : 4))) #define xph_filesz (size_t)((clazz == ELFCLASS32 \ ? elf_getu32(swap, ph32.p_filesz) \ : elf_getu64(swap, ph64.p_filesz))) #define xnh_addr (clazz == ELFCLASS32 \ ? (void *)&nh32 \ : (void *)&nh64) #define xph_memsz (size_t)((clazz == ELFCLASS32 \ ? elf_getu32(swap, ph32.p_memsz) \ : elf_getu64(swap, ph64.p_memsz))) #define xnh_sizeof (clazz == ELFCLASS32 \ ? sizeof(nh32) \ : sizeof(nh64)) #define xnh_type (clazz == ELFCLASS32 \ ? elf_getu32(swap, nh32.n_type) \ : elf_getu32(swap, nh64.n_type)) #define xnh_namesz (clazz == ELFCLASS32 \ ? elf_getu32(swap, nh32.n_namesz) \ : elf_getu32(swap, nh64.n_namesz)) #define xnh_descsz (clazz == ELFCLASS32 \ ? elf_getu32(swap, nh32.n_descsz) \ : elf_getu32(swap, nh64.n_descsz)) #define prpsoffsets(i) (clazz == ELFCLASS32 \ ? prpsoffsets32[i] \ : prpsoffsets64[i]) #define xcap_addr (clazz == ELFCLASS32 \ ? (void *)&cap32 \ : (void *)&cap64) #define xcap_sizeof (clazz == ELFCLASS32 \ ? sizeof cap32 \ : sizeof cap64) #define xcap_tag (clazz == ELFCLASS32 \ ? elf_getu32(swap, cap32.c_tag) \ : elf_getu64(swap, cap64.c_tag)) #define xcap_val (clazz == ELFCLASS32 \ ? elf_getu32(swap, cap32.c_un.c_val) \ : elf_getu64(swap, cap64.c_un.c_val)) #define xauxv_addr (clazz == ELFCLASS32 \ ? (void *)&auxv32 \ : (void *)&auxv64) #define xauxv_sizeof (clazz == ELFCLASS32 \ ? sizeof(auxv32) \ : sizeof(auxv64)) #define xauxv_type (clazz == ELFCLASS32 \ ? elf_getu32(swap, auxv32.a_type) \ : elf_getu64(swap, auxv64.a_type)) #define xauxv_val (clazz == ELFCLASS32 \ ? elf_getu32(swap, auxv32.a_v) \ : elf_getu64(swap, auxv64.a_v)) #ifdef ELFCORE /* * Try larger offsets first to avoid false matches * from earlier data that happen to look like strings. */ static const size_t prpsoffsets32[] = { #ifdef USE_NT_PSINFO 104, /* SunOS 5.x (command line) */ 88, /* SunOS 5.x (short name) */ #endif /* USE_NT_PSINFO */ 100, /* SunOS 5.x (command line) */ 84, /* SunOS 5.x (short name) */ 44, /* Linux (command line) */ 28, /* Linux 2.0.36 (short name) */ 8, /* FreeBSD */ }; static const size_t prpsoffsets64[] = { #ifdef USE_NT_PSINFO 152, /* SunOS 5.x (command line) */ 136, /* SunOS 5.x (short name) */ #endif /* USE_NT_PSINFO */ 136, /* SunOS 5.x, 64-bit (command line) */ 120, /* SunOS 5.x, 64-bit (short name) */ 56, /* Linux (command line) */ 40, /* Linux (tested on core from 2.4.x, short name) */ 16, /* FreeBSD, 64-bit */ }; #define NOFFSETS32 (sizeof prpsoffsets32 / sizeof prpsoffsets32[0]) #define NOFFSETS64 (sizeof prpsoffsets64 / sizeof prpsoffsets64[0]) #define NOFFSETS (clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64) /* * Look through the program headers of an executable image, searching * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or * "FreeBSD"; if one is found, try looking in various places in its * contents for a 16-character string containing only printable * characters - if found, that string should be the name of the program * that dropped core. Note: right after that 16-character string is, * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and * Linux, a longer string (80 characters, in 5.x, probably other * SVR4-flavored systems, and Linux) containing the start of the * command line for that program. * * SunOS 5.x core files contain two PT_NOTE sections, with the types * NT_PRPSINFO (old) and NT_PSINFO (new). These structs contain the * same info about the command name and command line, so it probably * isn't worthwhile to look for NT_PSINFO, but the offsets are provided * above (see USE_NT_PSINFO), in case we ever decide to do so. The * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent; * the SunOS 5.x file command relies on this (and prefers the latter). * * The signal number probably appears in a section of type NT_PRSTATUS, * but that's also rather OS-dependent, in ways that are harder to * dissect with heuristics, so I'm not bothering with the signal number. * (I suppose the signal number could be of interest in situations where * you don't have the binary of the program that dropped core; if you * *do* have that binary, the debugger will probably tell you what * signal it was.) */ #define OS_STYLE_SVR4 0 #define OS_STYLE_FREEBSD 1 #define OS_STYLE_NETBSD 2 private const char os_style_names[][8] = { "SVR4", "FreeBSD", "NetBSD", }; #define FLAGS_DID_CORE 0x001 #define FLAGS_DID_OS_NOTE 0x002 #define FLAGS_DID_BUILD_ID 0x004 #define FLAGS_DID_CORE_STYLE 0x008 #define FLAGS_DID_NETBSD_PAX 0x010 #define FLAGS_DID_NETBSD_MARCH 0x020 #define FLAGS_DID_NETBSD_CMODEL 0x040 #define FLAGS_DID_NETBSD_UNKNOWN 0x080 #define FLAGS_IS_CORE 0x100 #define FLAGS_DID_AUXV 0x200 private int dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num, size_t size, off_t fsize, int *flags, uint16_t *notecount) { Elf32_Phdr ph32; Elf64_Phdr ph64; size_t offset, len; unsigned char nbuf[BUFSIZ]; ssize_t bufsize; off_t ph_off = off; int ph_num = num; if (size != xph_sizeof) { if (file_printf(ms, ", corrupted program header size") == -1) return -1; return 0; } /* * Loop through all the program headers. */ for ( ; num; num--) { if (pread(fd, xph_addr, xph_sizeof, off) < (ssize_t)xph_sizeof) { file_badread(ms); return -1; } off += size; if (fsize != SIZE_UNKNOWN && xph_offset > fsize) { /* Perhaps warn here */ continue; } if (xph_type != PT_NOTE) continue; /* * This is a PT_NOTE section; loop through all the notes * in the section. */ len = xph_filesz < sizeof(nbuf) ? xph_filesz : sizeof(nbuf); if ((bufsize = pread(fd, nbuf, len, xph_offset)) == -1) { file_badread(ms); return -1; } offset = 0; for (;;) { if (offset >= (size_t)bufsize) break; offset = donote(ms, nbuf, offset, (size_t)bufsize, clazz, swap, 4, flags, notecount, fd, ph_off, ph_num, fsize); if (offset == 0) break; } } return 0; } #endif static void do_note_netbsd_version(struct magic_set *ms, int swap, void *v) { uint32_t desc; (void)memcpy(&desc, v, sizeof(desc)); desc = elf_getu32(swap, desc); if (file_printf(ms, ", for NetBSD") == -1) return; /* * The version number used to be stuck as 199905, and was thus * basically content-free. Newer versions of NetBSD have fixed * this and now use the encoding of __NetBSD_Version__: * * MMmmrrpp00 * * M = major version * m = minor version * r = release ["",A-Z,Z[A-Z] but numeric] * p = patchlevel */ if (desc > 100000000U) { uint32_t ver_patch = (desc / 100) % 100; uint32_t ver_rel = (desc / 10000) % 100; uint32_t ver_min = (desc / 1000000) % 100; uint32_t ver_maj = desc / 100000000; if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1) return; if (ver_rel == 0 && ver_patch != 0) { if (file_printf(ms, ".%u", ver_patch) == -1) return; } else if (ver_rel != 0) { while (ver_rel > 26) { if (file_printf(ms, "Z") == -1) return; ver_rel -= 26; } if (file_printf(ms, "%c", 'A' + ver_rel - 1) == -1) return; } } } static void do_note_freebsd_version(struct magic_set *ms, int swap, void *v) { uint32_t desc; (void)memcpy(&desc, v, sizeof(desc)); desc = elf_getu32(swap, desc); if (file_printf(ms, ", for FreeBSD") == -1) return; /* * Contents is __FreeBSD_version, whose relation to OS * versions is defined by a huge table in the Porter's * Handbook. This is the general scheme: * * Releases: * Mmp000 (before 4.10) * Mmi0p0 (before 5.0) * Mmm0p0 * * Development branches: * Mmpxxx (before 4.6) * Mmp1xx (before 4.10) * Mmi1xx (before 5.0) * M000xx (pre-M.0) * Mmm1xx * * M = major version * m = minor version * i = minor version increment (491000 -> 4.10) * p = patchlevel * x = revision * * The first release of FreeBSD to use ELF by default * was version 3.0. */ if (desc == 460002) { if (file_printf(ms, " 4.6.2") == -1) return; } else if (desc < 460100) { if (file_printf(ms, " %d.%d", desc / 100000, desc / 10000 % 10) == -1) return; if (desc / 1000 % 10 > 0) if (file_printf(ms, ".%d", desc / 1000 % 10) == -1) return; if ((desc % 1000 > 0) || (desc % 100000 == 0)) if (file_printf(ms, " (%d)", desc) == -1) return; } else if (desc < 500000) { if (file_printf(ms, " %d.%d", desc / 100000, desc / 10000 % 10 + desc / 1000 % 10) == -1) return; if (desc / 100 % 10 > 0) { if (file_printf(ms, " (%d)", desc) == -1) return; } else if (desc / 10 % 10 > 0) { if (file_printf(ms, ".%d", desc / 10 % 10) == -1) return; } } else { if (file_printf(ms, " %d.%d", desc / 100000, desc / 1000 % 100) == -1) return; if ((desc / 100 % 10 > 0) || (desc % 100000 / 100 == 0)) { if (file_printf(ms, " (%d)", desc) == -1) return; } else if (desc / 10 % 10 > 0) { if (file_printf(ms, ".%d", desc / 10 % 10) == -1) return; } } } private int /*ARGSUSED*/ do_bid_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, int swap __attribute__((__unused__)), uint32_t namesz, uint32_t descsz, size_t noff, size_t doff, int *flags) { if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 && type == NT_GNU_BUILD_ID && (descsz >= 4 || descsz <= 20)) { uint8_t desc[20]; const char *btype; uint32_t i; *flags |= FLAGS_DID_BUILD_ID; switch (descsz) { case 8: btype = "xxHash"; break; case 16: btype = "md5/uuid"; break; case 20: btype = "sha1"; break; default: btype = "unknown"; break; } if (file_printf(ms, ", BuildID[%s]=", btype) == -1) return 1; (void)memcpy(desc, &nbuf[doff], descsz); for (i = 0; i < descsz; i++) if (file_printf(ms, "%02x", desc[i]) == -1) return 1; return 1; } return 0; } private int do_os_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, int swap, uint32_t namesz, uint32_t descsz, size_t noff, size_t doff, int *flags) { if (namesz == 5 && strcmp((char *)&nbuf[noff], "SuSE") == 0 && type == NT_GNU_VERSION && descsz == 2) { *flags |= FLAGS_DID_OS_NOTE; file_printf(ms, ", for SuSE %d.%d", nbuf[doff], nbuf[doff + 1]); return 1; } if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 && type == NT_GNU_VERSION && descsz == 16) { uint32_t desc[4]; (void)memcpy(desc, &nbuf[doff], sizeof(desc)); *flags |= FLAGS_DID_OS_NOTE; if (file_printf(ms, ", for GNU/") == -1) return 1; switch (elf_getu32(swap, desc[0])) { case GNU_OS_LINUX: if (file_printf(ms, "Linux") == -1) return 1; break; case GNU_OS_HURD: if (file_printf(ms, "Hurd") == -1) return 1; break; case GNU_OS_SOLARIS: if (file_printf(ms, "Solaris") == -1) return 1; break; case GNU_OS_KFREEBSD: if (file_printf(ms, "kFreeBSD") == -1) return 1; break; case GNU_OS_KNETBSD: if (file_printf(ms, "kNetBSD") == -1) return 1; break; default: if (file_printf(ms, "") == -1) return 1; } if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]), elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1) return 1; return 1; } if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0) { if (type == NT_NETBSD_VERSION && descsz == 4) { *flags |= FLAGS_DID_OS_NOTE; do_note_netbsd_version(ms, swap, &nbuf[doff]); return 1; } } if (namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0) { if (type == NT_FREEBSD_VERSION && descsz == 4) { *flags |= FLAGS_DID_OS_NOTE; do_note_freebsd_version(ms, swap, &nbuf[doff]); return 1; } } if (namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 && type == NT_OPENBSD_VERSION && descsz == 4) { *flags |= FLAGS_DID_OS_NOTE; if (file_printf(ms, ", for OpenBSD") == -1) return 1; /* Content of note is always 0 */ return 1; } if (namesz == 10 && strcmp((char *)&nbuf[noff], "DragonFly") == 0 && type == NT_DRAGONFLY_VERSION && descsz == 4) { uint32_t desc; *flags |= FLAGS_DID_OS_NOTE; if (file_printf(ms, ", for DragonFly") == -1) return 1; (void)memcpy(&desc, &nbuf[doff], sizeof(desc)); desc = elf_getu32(swap, desc); if (file_printf(ms, " %d.%d.%d", desc / 100000, desc / 10000 % 10, desc % 10000) == -1) return 1; return 1; } return 0; } private int do_pax_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, int swap, uint32_t namesz, uint32_t descsz, size_t noff, size_t doff, int *flags) { if (namesz == 4 && strcmp((char *)&nbuf[noff], "PaX") == 0 && type == NT_NETBSD_PAX && descsz == 4) { static const char *pax[] = { "+mprotect", "-mprotect", "+segvguard", "-segvguard", "+ASLR", "-ASLR", }; uint32_t desc; size_t i; int did = 0; *flags |= FLAGS_DID_NETBSD_PAX; (void)memcpy(&desc, &nbuf[doff], sizeof(desc)); desc = elf_getu32(swap, desc); if (desc && file_printf(ms, ", PaX: ") == -1) return 1; for (i = 0; i < __arraycount(pax); i++) { if (((1 << (int)i) & desc) == 0) continue; if (file_printf(ms, "%s%s", did++ ? "," : "", pax[i]) == -1) return 1; } return 1; } return 0; } private int do_core_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, int swap, uint32_t namesz, uint32_t descsz, size_t noff, size_t doff, int *flags, size_t size, int clazz) { #ifdef ELFCORE int os_style = -1; /* * Sigh. The 2.0.36 kernel in Debian 2.1, at * least, doesn't correctly implement name * sections, in core dumps, as specified by * the "Program Linking" section of "UNIX(R) System * V Release 4 Programmer's Guide: ANSI C and * Programming Support Tools", because my copy * clearly says "The first 'namesz' bytes in 'name' * contain a *null-terminated* [emphasis mine] * character representation of the entry's owner * or originator", but the 2.0.36 kernel code * doesn't include the terminating null in the * name.... */ if ((namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) || (namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) { os_style = OS_STYLE_SVR4; } if ((namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) { os_style = OS_STYLE_FREEBSD; } if ((namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11) == 0)) { os_style = OS_STYLE_NETBSD; } if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) { if (file_printf(ms, ", %s-style", os_style_names[os_style]) == -1) return 1; *flags |= FLAGS_DID_CORE_STYLE; } switch (os_style) { case OS_STYLE_NETBSD: if (type == NT_NETBSD_CORE_PROCINFO) { char sbuf[512]; uint32_t signo; /* * Extract the program name. It is at * offset 0x7c, and is up to 32-bytes, * including the terminating NUL. */ if (file_printf(ms, ", from '%.31s'", file_printable(sbuf, sizeof(sbuf), (const char *)&nbuf[doff + 0x7c])) == -1) return 1; /* * Extract the signal number. It is at * offset 0x08. */ (void)memcpy(&signo, &nbuf[doff + 0x08], sizeof(signo)); if (file_printf(ms, " (signal %u)", elf_getu32(swap, signo)) == -1) return 1; *flags |= FLAGS_DID_CORE; return 1; } break; default: if (type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) { size_t i, j; unsigned char c; /* * Extract the program name. We assume * it to be 16 characters (that's what it * is in SunOS 5.x and Linux). * * Unfortunately, it's at a different offset * in various OSes, so try multiple offsets. * If the characters aren't all printable, * reject it. */ for (i = 0; i < NOFFSETS; i++) { unsigned char *cname, *cp; size_t reloffset = prpsoffsets(i); size_t noffset = doff + reloffset; size_t k; for (j = 0; j < 16; j++, noffset++, reloffset++) { /* * Make sure we're not past * the end of the buffer; if * we are, just give up. */ if (noffset >= size) goto tryanother; /* * Make sure we're not past * the end of the contents; * if we are, this obviously * isn't the right offset. */ if (reloffset >= descsz) goto tryanother; c = nbuf[noffset]; if (c == '\0') { /* * A '\0' at the * beginning is * obviously wrong. * Any other '\0' * means we're done. */ if (j == 0) goto tryanother; else break; } else { /* * A nonprintable * character is also * wrong. */ if (!isprint(c) || isquote(c)) goto tryanother; } } /* * Well, that worked. */ /* * Try next offsets, in case this match is * in the middle of a string. */ for (k = i + 1 ; k < NOFFSETS; k++) { size_t no; int adjust = 1; if (prpsoffsets(k) >= prpsoffsets(i)) continue; for (no = doff + prpsoffsets(k); no < doff + prpsoffsets(i); no++) adjust = adjust && isprint(nbuf[no]); if (adjust) i = k; } cname = (unsigned char *) &nbuf[doff + prpsoffsets(i)]; for (cp = cname; *cp && isprint(*cp); cp++) continue; /* * Linux apparently appends a space at the end * of the command line: remove it. */ while (cp > cname && isspace(cp[-1])) cp--; if (file_printf(ms, ", from '%.*s'", (int)(cp - cname), cname) == -1) return 1; *flags |= FLAGS_DID_CORE; return 1; tryanother: ; } } break; } #endif return 0; } private off_t get_offset_from_virtaddr(struct magic_set *ms, int swap, int clazz, int fd, off_t off, int num, off_t fsize, uint64_t virtaddr) { Elf32_Phdr ph32; Elf64_Phdr ph64; /* * Loop through all the program headers and find the header with * virtual address in which the "virtaddr" belongs to. */ for ( ; num; num--) { if (pread(fd, xph_addr, xph_sizeof, off) < (ssize_t)xph_sizeof) { file_badread(ms); return -1; } off += xph_sizeof; if (fsize != SIZE_UNKNOWN && xph_offset > fsize) { /* Perhaps warn here */ continue; } if (virtaddr >= xph_vaddr && virtaddr < xph_vaddr + xph_filesz) return xph_offset + (virtaddr - xph_vaddr); } return 0; } private size_t get_string_on_virtaddr(struct magic_set *ms, int swap, int clazz, int fd, off_t ph_off, int ph_num, off_t fsize, uint64_t virtaddr, char *buf, ssize_t buflen) { char *bptr; off_t offset; if (buflen == 0) return 0; offset = get_offset_from_virtaddr(ms, swap, clazz, fd, ph_off, ph_num, fsize, virtaddr); if ((buflen = pread(fd, buf, CAST(size_t, buflen), offset)) <= 0) { file_badread(ms); return 0; } buf[buflen - 1] = '\0'; /* We expect only printable characters, so return if buffer contains * non-printable character before the '\0' or just '\0'. */ for (bptr = buf; *bptr && isprint((unsigned char)*bptr); bptr++) continue; if (*bptr != '\0') return 0; return bptr - buf; } private int do_auxv_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type, int swap, uint32_t namesz __attribute__((__unused__)), uint32_t descsz __attribute__((__unused__)), size_t noff __attribute__((__unused__)), size_t doff, int *flags, size_t size __attribute__((__unused__)), int clazz, int fd, off_t ph_off, int ph_num, off_t fsize) { #ifdef ELFCORE Aux32Info auxv32; Aux64Info auxv64; size_t elsize = xauxv_sizeof; const char *tag; int is_string; size_t nval; if (type != NT_AUXV || (*flags & FLAGS_IS_CORE) == 0) return 0; *flags |= FLAGS_DID_AUXV; nval = 0; for (size_t off = 0; off + elsize <= descsz; off += elsize) { (void)memcpy(xauxv_addr, &nbuf[doff + off], xauxv_sizeof); /* Limit processing to 50 vector entries to prevent DoS */ if (nval++ >= 50) { file_error(ms, 0, "Too many ELF Auxv elements"); return 1; } switch(xauxv_type) { case AT_LINUX_EXECFN: is_string = 1; tag = "execfn"; break; case AT_LINUX_PLATFORM: is_string = 1; tag = "platform"; break; case AT_LINUX_UID: is_string = 0; tag = "real uid"; break; case AT_LINUX_GID: is_string = 0; tag = "real gid"; break; case AT_LINUX_EUID: is_string = 0; tag = "effective uid"; break; case AT_LINUX_EGID: is_string = 0; tag = "effective gid"; break; default: is_string = 0; tag = NULL; break; } if (tag == NULL) continue; if (is_string) { char buf[256]; ssize_t buflen; buflen = get_string_on_virtaddr(ms, swap, clazz, fd, ph_off, ph_num, fsize, xauxv_val, buf, sizeof(buf)); if (buflen == 0) continue; if (file_printf(ms, ", %s: '%s'", tag, buf) == -1) return 0; } else { if (file_printf(ms, ", %s: %d", tag, (int) xauxv_val) == -1) return 0; } } return 1; #else return 0; #endif } private size_t donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size, int clazz, int swap, size_t align, int *flags, uint16_t *notecount, int fd, off_t ph_off, int ph_num, off_t fsize) { Elf32_Nhdr nh32; Elf64_Nhdr nh64; size_t noff, doff; uint32_t namesz, descsz; unsigned char *nbuf = CAST(unsigned char *, vbuf); if (*notecount == 0) return 0; --*notecount; if (xnh_sizeof + offset > size) { /* * We're out of note headers. */ return xnh_sizeof + offset; } (void)memcpy(xnh_addr, &nbuf[offset], xnh_sizeof); offset += xnh_sizeof; namesz = xnh_namesz; descsz = xnh_descsz; if ((namesz == 0) && (descsz == 0)) { /* * We're out of note headers. */ return (offset >= size) ? offset : size; } if (namesz & 0x80000000) { (void)file_printf(ms, ", bad note name size 0x%lx", (unsigned long)namesz); return 0; } if (descsz & 0x80000000) { (void)file_printf(ms, ", bad note description size 0x%lx", (unsigned long)descsz); return 0; } noff = offset; doff = ELF_ALIGN(offset + namesz); if (offset + namesz > size) { /* * We're past the end of the buffer. */ return doff; } offset = ELF_ALIGN(doff + descsz); if (doff + descsz > size) { /* * We're past the end of the buffer. */ return (offset >= size) ? offset : size; } if ((*flags & FLAGS_DID_OS_NOTE) == 0) { if (do_os_note(ms, nbuf, xnh_type, swap, namesz, descsz, noff, doff, flags)) return offset; } if ((*flags & FLAGS_DID_BUILD_ID) == 0) { if (do_bid_note(ms, nbuf, xnh_type, swap, namesz, descsz, noff, doff, flags)) return offset; } if ((*flags & FLAGS_DID_NETBSD_PAX) == 0) { if (do_pax_note(ms, nbuf, xnh_type, swap, namesz, descsz, noff, doff, flags)) return offset; } if ((*flags & FLAGS_DID_CORE) == 0) { if (do_core_note(ms, nbuf, xnh_type, swap, namesz, descsz, noff, doff, flags, size, clazz)) return offset; } if ((*flags & FLAGS_DID_AUXV) == 0) { if (do_auxv_note(ms, nbuf, xnh_type, swap, namesz, descsz, noff, doff, flags, size, clazz, fd, ph_off, ph_num, fsize)) return offset; } if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0) { if (descsz > 100) descsz = 100; switch (xnh_type) { case NT_NETBSD_VERSION: return offset; case NT_NETBSD_MARCH: if (*flags & FLAGS_DID_NETBSD_MARCH) return offset; *flags |= FLAGS_DID_NETBSD_MARCH; if (file_printf(ms, ", compiled for: %.*s", (int)descsz, (const char *)&nbuf[doff]) == -1) return offset; break; case NT_NETBSD_CMODEL: if (*flags & FLAGS_DID_NETBSD_CMODEL) return offset; *flags |= FLAGS_DID_NETBSD_CMODEL; if (file_printf(ms, ", compiler model: %.*s", (int)descsz, (const char *)&nbuf[doff]) == -1) return offset; break; default: if (*flags & FLAGS_DID_NETBSD_UNKNOWN) return offset; *flags |= FLAGS_DID_NETBSD_UNKNOWN; if (file_printf(ms, ", note=%u", xnh_type) == -1) return offset; break; } return offset; } return offset; } /* SunOS 5.x hardware capability descriptions */ typedef struct cap_desc { uint64_t cd_mask; const char *cd_name; } cap_desc_t; static const cap_desc_t cap_desc_sparc[] = { { AV_SPARC_MUL32, "MUL32" }, { AV_SPARC_DIV32, "DIV32" }, { AV_SPARC_FSMULD, "FSMULD" }, { AV_SPARC_V8PLUS, "V8PLUS" }, { AV_SPARC_POPC, "POPC" }, { AV_SPARC_VIS, "VIS" }, { AV_SPARC_VIS2, "VIS2" }, { AV_SPARC_ASI_BLK_INIT, "ASI_BLK_INIT" }, { AV_SPARC_FMAF, "FMAF" }, { AV_SPARC_FJFMAU, "FJFMAU" }, { AV_SPARC_IMA, "IMA" }, { 0, NULL } }; static const cap_desc_t cap_desc_386[] = { { AV_386_FPU, "FPU" }, { AV_386_TSC, "TSC" }, { AV_386_CX8, "CX8" }, { AV_386_SEP, "SEP" }, { AV_386_AMD_SYSC, "AMD_SYSC" }, { AV_386_CMOV, "CMOV" }, { AV_386_MMX, "MMX" }, { AV_386_AMD_MMX, "AMD_MMX" }, { AV_386_AMD_3DNow, "AMD_3DNow" }, { AV_386_AMD_3DNowx, "AMD_3DNowx" }, { AV_386_FXSR, "FXSR" }, { AV_386_SSE, "SSE" }, { AV_386_SSE2, "SSE2" }, { AV_386_PAUSE, "PAUSE" }, { AV_386_SSE3, "SSE3" }, { AV_386_MON, "MON" }, { AV_386_CX16, "CX16" }, { AV_386_AHF, "AHF" }, { AV_386_TSCP, "TSCP" }, { AV_386_AMD_SSE4A, "AMD_SSE4A" }, { AV_386_POPCNT, "POPCNT" }, { AV_386_AMD_LZCNT, "AMD_LZCNT" }, { AV_386_SSSE3, "SSSE3" }, { AV_386_SSE4_1, "SSE4.1" }, { AV_386_SSE4_2, "SSE4.2" }, { 0, NULL } }; private int doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num, size_t size, off_t fsize, int mach, int strtab, int *flags, uint16_t *notecount) { Elf32_Shdr sh32; Elf64_Shdr sh64; int stripped = 1, has_debug_info = 1; size_t nbadcap = 0; void *nbuf; off_t noff, coff, name_off; uint64_t cap_hw1 = 0; /* SunOS 5.x hardware capabilites */ uint64_t cap_sf1 = 0; /* SunOS 5.x software capabilites */ char name[50]; ssize_t namesize; if (size != xsh_sizeof) { if (file_printf(ms, ", corrupted section header size") == -1) return -1; return 0; } /* Read offset of name section to be able to read section names later */ if (pread(fd, xsh_addr, xsh_sizeof, CAST(off_t, (off + size * strtab))) < (ssize_t)xsh_sizeof) { if (file_printf(ms, ", missing section headers") == -1) return -1; return 0; } name_off = xsh_offset; for ( ; num; num--) { /* Read the name of this section. */ if ((namesize = pread(fd, name, sizeof(name) - 1, name_off + xsh_name)) == -1) { file_badread(ms); return -1; } name[namesize] = '\0'; if (strcmp(name, ".debug_info") == 0) { has_debug_info = 1; stripped = 0; } if (pread(fd, xsh_addr, xsh_sizeof, off) < (ssize_t)xsh_sizeof) { file_badread(ms); return -1; } off += size; /* Things we can determine before we seek */ switch (xsh_type) { case SHT_SYMTAB: #if 0 case SHT_DYNSYM: #endif stripped = 0; break; default: if (fsize != SIZE_UNKNOWN && xsh_offset > fsize) { /* Perhaps warn here */ continue; } break; } /* Things we can determine when we seek */ switch (xsh_type) { case SHT_NOTE: if ((uintmax_t)(xsh_size + xsh_offset) > (uintmax_t)fsize) { if (file_printf(ms, ", note offset/size 0x%" INTMAX_T_FORMAT "x+0x%" INTMAX_T_FORMAT "x exceeds" " file size 0x%" INTMAX_T_FORMAT "x", (uintmax_t)xsh_offset, (uintmax_t)xsh_size, (uintmax_t)fsize) == -1) return -1; return 0; } if ((nbuf = malloc(xsh_size)) == NULL) { file_error(ms, errno, "Cannot allocate memory" " for note"); return -1; } if (pread(fd, nbuf, xsh_size, xsh_offset) < (ssize_t)xsh_size) { file_badread(ms); free(nbuf); return -1; } noff = 0; for (;;) { if (noff >= (off_t)xsh_size) break; noff = donote(ms, nbuf, (size_t)noff, xsh_size, clazz, swap, 4, flags, notecount, fd, 0, 0, 0); if (noff == 0) break; } free(nbuf); break; case SHT_SUNW_cap: switch (mach) { case EM_SPARC: case EM_SPARCV9: case EM_IA_64: case EM_386: case EM_AMD64: break; default: goto skip; } if (nbadcap > 5) break; if (lseek(fd, xsh_offset, SEEK_SET) == (off_t)-1) { file_badseek(ms); return -1; } coff = 0; for (;;) { Elf32_Cap cap32; Elf64_Cap cap64; char cbuf[/*CONSTCOND*/ MAX(sizeof cap32, sizeof cap64)]; if ((coff += xcap_sizeof) > (off_t)xsh_size) break; if (read(fd, cbuf, (size_t)xcap_sizeof) != (ssize_t)xcap_sizeof) { file_badread(ms); return -1; } if (cbuf[0] == 'A') { #ifdef notyet char *p = cbuf + 1; uint32_t len, tag; memcpy(&len, p, sizeof(len)); p += 4; len = getu32(swap, len); if (memcmp("gnu", p, 3) != 0) { if (file_printf(ms, ", unknown capability %.3s", p) == -1) return -1; break; } p += strlen(p) + 1; tag = *p++; memcpy(&len, p, sizeof(len)); p += 4; len = getu32(swap, len); if (tag != 1) { if (file_printf(ms, ", unknown gnu" " capability tag %d", tag) == -1) return -1; break; } // gnu attributes #endif break; } (void)memcpy(xcap_addr, cbuf, xcap_sizeof); switch (xcap_tag) { case CA_SUNW_NULL: break; case CA_SUNW_HW_1: cap_hw1 |= xcap_val; break; case CA_SUNW_SF_1: cap_sf1 |= xcap_val; break; default: if (file_printf(ms, ", with unknown capability " "0x%" INT64_T_FORMAT "x = 0x%" INT64_T_FORMAT "x", (unsigned long long)xcap_tag, (unsigned long long)xcap_val) == -1) return -1; if (nbadcap++ > 2) coff = xsh_size; break; } } /*FALLTHROUGH*/ skip: default: break; } } if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1) return -1; if (has_debug_info) { if (file_printf(ms, ", with debug_info") == -1) return -1; } if (cap_hw1) { const cap_desc_t *cdp; switch (mach) { case EM_SPARC: case EM_SPARC32PLUS: case EM_SPARCV9: cdp = cap_desc_sparc; break; case EM_386: case EM_IA_64: case EM_AMD64: cdp = cap_desc_386; break; default: cdp = NULL; break; } if (file_printf(ms, ", uses") == -1) return -1; if (cdp) { while (cdp->cd_name) { if (cap_hw1 & cdp->cd_mask) { if (file_printf(ms, " %s", cdp->cd_name) == -1) return -1; cap_hw1 &= ~cdp->cd_mask; } ++cdp; } if (cap_hw1) if (file_printf(ms, " unknown hardware capability 0x%" INT64_T_FORMAT "x", (unsigned long long)cap_hw1) == -1) return -1; } else { if (file_printf(ms, " hardware capability 0x%" INT64_T_FORMAT "x", (unsigned long long)cap_hw1) == -1) return -1; } } if (cap_sf1) { if (cap_sf1 & SF1_SUNW_FPUSED) { if (file_printf(ms, (cap_sf1 & SF1_SUNW_FPKNWN) ? ", uses frame pointer" : ", not known to use frame pointer") == -1) return -1; } cap_sf1 &= ~SF1_SUNW_MASK; if (cap_sf1) if (file_printf(ms, ", with unknown software capability 0x%" INT64_T_FORMAT "x", (unsigned long long)cap_sf1) == -1) return -1; } return 0; } /* * Look through the program headers of an executable image, searching * for a PT_INTERP section; if one is found, it's dynamically linked, * otherwise it's statically linked. */ private int dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num, size_t size, off_t fsize, int sh_num, int *flags, uint16_t *notecount) { Elf32_Phdr ph32; Elf64_Phdr ph64; const char *linking_style = "statically"; const char *interp = ""; unsigned char nbuf[BUFSIZ]; char ibuf[BUFSIZ]; ssize_t bufsize; size_t offset, align, len; if (size != xph_sizeof) { if (file_printf(ms, ", corrupted program header size") == -1) return -1; return 0; } for ( ; num; num--) { if (pread(fd, xph_addr, xph_sizeof, off) < (ssize_t)xph_sizeof) { file_badread(ms); return -1; } off += size; bufsize = 0; align = 4; /* Things we can determine before we seek */ switch (xph_type) { case PT_DYNAMIC: linking_style = "dynamically"; break; case PT_NOTE: if (sh_num) /* Did this through section headers */ continue; if (((align = xph_align) & 0x80000000UL) != 0 || align < 4) { if (file_printf(ms, ", invalid note alignment 0x%lx", (unsigned long)align) == -1) return -1; align = 4; } /*FALLTHROUGH*/ case PT_INTERP: len = xph_filesz < sizeof(nbuf) ? xph_filesz : sizeof(nbuf); bufsize = pread(fd, nbuf, len, xph_offset); if (bufsize == -1) { file_badread(ms); return -1; } break; default: if (fsize != SIZE_UNKNOWN && xph_offset > fsize) { /* Maybe warn here? */ continue; } break; } /* Things we can determine when we seek */ switch (xph_type) { case PT_INTERP: if (bufsize && nbuf[0]) { nbuf[bufsize - 1] = '\0'; interp = (const char *)nbuf; } else interp = "*empty*"; break; case PT_NOTE: /* * This is a PT_NOTE section; loop through all the notes * in the section. */ offset = 0; for (;;) { if (offset >= (size_t)bufsize) break; offset = donote(ms, nbuf, offset, (size_t)bufsize, clazz, swap, align, flags, notecount, fd, 0, 0, 0); if (offset == 0) break; } break; default: break; } } if (file_printf(ms, ", %s linked", linking_style) == -1) return -1; if (interp[0]) if (file_printf(ms, ", interpreter %s", file_printable(ibuf, sizeof(ibuf), interp)) == -1) return -1; return 0; } protected int file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf, size_t nbytes) { union { int32_t l; char c[sizeof (int32_t)]; } u; int clazz; int swap; struct stat st; off_t fsize; int flags = 0; Elf32_Ehdr elf32hdr; Elf64_Ehdr elf64hdr; uint16_t type, phnum, shnum, notecount; if (ms->flags & (MAGIC_MIME|MAGIC_APPLE|MAGIC_EXTENSION)) return 0; /* * ELF executables have multiple section headers in arbitrary * file locations and thus file(1) cannot determine it from easily. * Instead we traverse thru all section headers until a symbol table * one is found or else the binary is stripped. * Return immediately if it's not ELF (so we avoid pipe2file unless needed). */ if (buf[EI_MAG0] != ELFMAG0 || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1) || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3) return 0; /* * If we cannot seek, it must be a pipe, socket or fifo. */ if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE)) fd = file_pipe2file(ms, fd, buf, nbytes); if (fstat(fd, &st) == -1) { file_badread(ms); return -1; } if (S_ISREG(st.st_mode) || st.st_size != 0) fsize = st.st_size; else fsize = SIZE_UNKNOWN; clazz = buf[EI_CLASS]; switch (clazz) { case ELFCLASS32: #undef elf_getu #define elf_getu(a, b) elf_getu32(a, b) #undef elfhdr #define elfhdr elf32hdr #include "elfclass.h" case ELFCLASS64: #undef elf_getu #define elf_getu(a, b) elf_getu64(a, b) #undef elfhdr #define elfhdr elf64hdr #include "elfclass.h" default: if (file_printf(ms, ", unknown class %d", clazz) == -1) return -1; break; } return 0; } #endif