diff options
Diffstat (limited to 'REORG.TODO/elf/dl-sysdep.c')
| -rw-r--r-- | REORG.TODO/elf/dl-sysdep.c | 360 |
1 files changed, 360 insertions, 0 deletions
diff --git a/REORG.TODO/elf/dl-sysdep.c b/REORG.TODO/elf/dl-sysdep.c new file mode 100644 index 0000000000..4053ff3c07 --- /dev/null +++ b/REORG.TODO/elf/dl-sysdep.c @@ -0,0 +1,360 @@ +/* Operating system support for run-time dynamic linker. Generic Unix version. + Copyright (C) 1995-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +/* We conditionalize the whole of this file rather than simply eliding it + from the static build, because other sysdeps/ versions of this file + might define things needed by a static build. */ + +#ifdef SHARED + +#include <assert.h> +#include <elf.h> +#include <errno.h> +#include <fcntl.h> +#include <libintl.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/mman.h> +#include <ldsodefs.h> +#include <_itoa.h> +#include <fpu_control.h> + +#include <entry.h> +#include <dl-machine.h> +#include <dl-procinfo.h> +#include <dl-osinfo.h> +#include <hp-timing.h> +#include <tls.h> + +#include <dl-tunables.h> + +extern char **_environ attribute_hidden; +extern char _end[] attribute_hidden; + +/* Protect SUID program against misuse of file descriptors. */ +extern void __libc_check_standard_fds (void); + +#ifdef NEED_DL_BASE_ADDR +ElfW(Addr) _dl_base_addr; +#endif +int __libc_enable_secure attribute_relro = 0; +rtld_hidden_data_def (__libc_enable_secure) +int __libc_multiple_libcs = 0; /* Defining this here avoids the inclusion + of init-first. */ +/* This variable contains the lowest stack address ever used. */ +void *__libc_stack_end attribute_relro = NULL; +rtld_hidden_data_def(__libc_stack_end) +void *_dl_random attribute_relro = NULL; + +#ifndef DL_FIND_ARG_COMPONENTS +# define DL_FIND_ARG_COMPONENTS(cookie, argc, argv, envp, auxp) \ + do { \ + void **_tmp; \ + (argc) = *(long int *) cookie; \ + (argv) = (char **) ((long int *) cookie + 1); \ + (envp) = (argv) + (argc) + 1; \ + for (_tmp = (void **) (envp); *_tmp; ++_tmp) \ + continue; \ + (auxp) = (void *) ++_tmp; \ + } while (0) +#endif + +#ifndef DL_STACK_END +# define DL_STACK_END(cookie) ((void *) (cookie)) +#endif + +ElfW(Addr) +_dl_sysdep_start (void **start_argptr, + void (*dl_main) (const ElfW(Phdr) *phdr, ElfW(Word) phnum, + ElfW(Addr) *user_entry, ElfW(auxv_t) *auxv)) +{ + const ElfW(Phdr) *phdr = NULL; + ElfW(Word) phnum = 0; + ElfW(Addr) user_entry; + ElfW(auxv_t) *av; +#ifdef HAVE_AUX_SECURE +# define set_seen(tag) (tag) /* Evaluate for the side effects. */ +# define set_seen_secure() ((void) 0) +#else + uid_t uid = 0; + gid_t gid = 0; + unsigned int seen = 0; +# define set_seen_secure() (seen = -1) +# ifdef HAVE_AUX_XID +# define set_seen(tag) (tag) /* Evaluate for the side effects. */ +# else +# define M(type) (1 << (type)) +# define set_seen(tag) seen |= M ((tag)->a_type) +# endif +#endif +#ifdef NEED_DL_SYSINFO + uintptr_t new_sysinfo = 0; +#endif + + __libc_stack_end = DL_STACK_END (start_argptr); + DL_FIND_ARG_COMPONENTS (start_argptr, _dl_argc, _dl_argv, _environ, + GLRO(dl_auxv)); + + user_entry = (ElfW(Addr)) ENTRY_POINT; + GLRO(dl_platform) = NULL; /* Default to nothing known about the platform. */ + + for (av = GLRO(dl_auxv); av->a_type != AT_NULL; set_seen (av++)) + switch (av->a_type) + { + case AT_PHDR: + phdr = (void *) av->a_un.a_val; + break; + case AT_PHNUM: + phnum = av->a_un.a_val; + break; + case AT_PAGESZ: + GLRO(dl_pagesize) = av->a_un.a_val; + break; + case AT_ENTRY: + user_entry = av->a_un.a_val; + break; +#ifdef NEED_DL_BASE_ADDR + case AT_BASE: + _dl_base_addr = av->a_un.a_val; + break; +#endif +#ifndef HAVE_AUX_SECURE + case AT_UID: + case AT_EUID: + uid ^= av->a_un.a_val; + break; + case AT_GID: + case AT_EGID: + gid ^= av->a_un.a_val; + break; +#endif + case AT_SECURE: +#ifndef HAVE_AUX_SECURE + seen = -1; +#endif + __libc_enable_secure = av->a_un.a_val; + break; + case AT_PLATFORM: + GLRO(dl_platform) = (void *) av->a_un.a_val; + break; + case AT_HWCAP: + GLRO(dl_hwcap) = (unsigned long int) av->a_un.a_val; + break; + case AT_HWCAP2: + GLRO(dl_hwcap2) = (unsigned long int) av->a_un.a_val; + break; + case AT_CLKTCK: + GLRO(dl_clktck) = av->a_un.a_val; + break; + case AT_FPUCW: + GLRO(dl_fpu_control) = av->a_un.a_val; + break; +#ifdef NEED_DL_SYSINFO + case AT_SYSINFO: + new_sysinfo = av->a_un.a_val; + break; +#endif +#ifdef NEED_DL_SYSINFO_DSO + case AT_SYSINFO_EHDR: + GLRO(dl_sysinfo_dso) = (void *) av->a_un.a_val; + break; +#endif + case AT_RANDOM: + _dl_random = (void *) av->a_un.a_val; + break; +#ifdef DL_PLATFORM_AUXV + DL_PLATFORM_AUXV +#endif + } + +#ifndef HAVE_AUX_SECURE + if (seen != -1) + { + /* Fill in the values we have not gotten from the kernel through the + auxiliary vector. */ +# ifndef HAVE_AUX_XID +# define SEE(UID, var, uid) \ + if ((seen & M (AT_##UID)) == 0) var ^= __get##uid () + SEE (UID, uid, uid); + SEE (EUID, uid, euid); + SEE (GID, gid, gid); + SEE (EGID, gid, egid); +# endif + + /* If one of the two pairs of IDs does not match this is a setuid + or setgid run. */ + __libc_enable_secure = uid | gid; + } +#endif + +#ifndef HAVE_AUX_PAGESIZE + if (GLRO(dl_pagesize) == 0) + GLRO(dl_pagesize) = __getpagesize (); +#endif + +#ifdef NEED_DL_SYSINFO + if (new_sysinfo != 0) + { +# ifdef NEED_DL_SYSINFO_DSO + /* Only set the sysinfo value if we also have the vsyscall DSO. */ + if (GLRO(dl_sysinfo_dso) != 0) +# endif + GLRO(dl_sysinfo) = new_sysinfo; + } +#endif + + __tunables_init (_environ); + +#ifdef DL_SYSDEP_INIT + DL_SYSDEP_INIT; +#endif + +#ifdef DL_PLATFORM_INIT + DL_PLATFORM_INIT; +#endif + + /* Determine the length of the platform name. */ + if (GLRO(dl_platform) != NULL) + GLRO(dl_platformlen) = strlen (GLRO(dl_platform)); + + if (__sbrk (0) == _end) + /* The dynamic linker was run as a program, and so the initial break + starts just after our bss, at &_end. The malloc in dl-minimal.c + will consume the rest of this page, so tell the kernel to move the + break up that far. When the user program examines its break, it + will see this new value and not clobber our data. */ + __sbrk (GLRO(dl_pagesize) + - ((_end - (char *) 0) & (GLRO(dl_pagesize) - 1))); + + /* If this is a SUID program we make sure that FDs 0, 1, and 2 are + allocated. If necessary we are doing it ourself. If it is not + possible we stop the program. */ + if (__builtin_expect (__libc_enable_secure, 0)) + __libc_check_standard_fds (); + + (*dl_main) (phdr, phnum, &user_entry, GLRO(dl_auxv)); + return user_entry; +} + +void +internal_function +_dl_sysdep_start_cleanup (void) +{ +} + +void +internal_function +_dl_show_auxv (void) +{ + char buf[64]; + ElfW(auxv_t) *av; + + /* Terminate string. */ + buf[63] = '\0'; + + /* The following code assumes that the AT_* values are encoded + starting from 0 with AT_NULL, 1 for AT_IGNORE, and all other values + close by (otherwise the array will be too large). In case we have + to support a platform where these requirements are not fulfilled + some alternative implementation has to be used. */ + for (av = GLRO(dl_auxv); av->a_type != AT_NULL; ++av) + { + static const struct + { + const char label[17]; + enum { unknown = 0, dec, hex, str, ignore } form : 8; + } auxvars[] = + { + [AT_EXECFD - 2] = { "EXECFD: ", dec }, + [AT_EXECFN - 2] = { "EXECFN: ", str }, + [AT_PHDR - 2] = { "PHDR: 0x", hex }, + [AT_PHENT - 2] = { "PHENT: ", dec }, + [AT_PHNUM - 2] = { "PHNUM: ", dec }, + [AT_PAGESZ - 2] = { "PAGESZ: ", dec }, + [AT_BASE - 2] = { "BASE: 0x", hex }, + [AT_FLAGS - 2] = { "FLAGS: 0x", hex }, + [AT_ENTRY - 2] = { "ENTRY: 0x", hex }, + [AT_NOTELF - 2] = { "NOTELF: ", hex }, + [AT_UID - 2] = { "UID: ", dec }, + [AT_EUID - 2] = { "EUID: ", dec }, + [AT_GID - 2] = { "GID: ", dec }, + [AT_EGID - 2] = { "EGID: ", dec }, + [AT_PLATFORM - 2] = { "PLATFORM: ", str }, + [AT_HWCAP - 2] = { "HWCAP: ", hex }, + [AT_CLKTCK - 2] = { "CLKTCK: ", dec }, + [AT_FPUCW - 2] = { "FPUCW: ", hex }, + [AT_DCACHEBSIZE - 2] = { "DCACHEBSIZE: 0x", hex }, + [AT_ICACHEBSIZE - 2] = { "ICACHEBSIZE: 0x", hex }, + [AT_UCACHEBSIZE - 2] = { "UCACHEBSIZE: 0x", hex }, + [AT_IGNOREPPC - 2] = { "IGNOREPPC", ignore }, + [AT_SECURE - 2] = { "SECURE: ", dec }, + [AT_BASE_PLATFORM - 2] = { "BASE_PLATFORM:", str }, + [AT_SYSINFO - 2] = { "SYSINFO: 0x", hex }, + [AT_SYSINFO_EHDR - 2] = { "SYSINFO_EHDR: 0x", hex }, + [AT_RANDOM - 2] = { "RANDOM: 0x", hex }, + [AT_HWCAP2 - 2] = { "HWCAP2: 0x", hex }, + }; + unsigned int idx = (unsigned int) (av->a_type - 2); + + if ((unsigned int) av->a_type < 2u + || (idx < sizeof (auxvars) / sizeof (auxvars[0]) + && auxvars[idx].form == ignore)) + continue; + + assert (AT_NULL == 0); + assert (AT_IGNORE == 1); + + if (av->a_type == AT_HWCAP || av->a_type == AT_HWCAP2) + { + /* These are handled in a special way per platform. */ + if (_dl_procinfo (av->a_type, av->a_un.a_val) == 0) + continue; + } + + if (idx < sizeof (auxvars) / sizeof (auxvars[0]) + && auxvars[idx].form != unknown) + { + const char *val = (char *) av->a_un.a_val; + + if (__builtin_expect (auxvars[idx].form, dec) == dec) + val = _itoa ((unsigned long int) av->a_un.a_val, + buf + sizeof buf - 1, 10, 0); + else if (__builtin_expect (auxvars[idx].form, hex) == hex) + val = _itoa ((unsigned long int) av->a_un.a_val, + buf + sizeof buf - 1, 16, 0); + + _dl_printf ("AT_%s%s\n", auxvars[idx].label, val); + + continue; + } + + /* Unknown value: print a generic line. */ + char buf2[17]; + buf2[sizeof (buf2) - 1] = '\0'; + const char *val2 = _itoa ((unsigned long int) av->a_un.a_val, + buf2 + sizeof buf2 - 1, 16, 0); + const char *val = _itoa ((unsigned long int) av->a_type, + buf + sizeof buf - 1, 16, 0); + _dl_printf ("AT_??? (0x%s): 0x%s\n", val, val2); + } +} + +#endif |