diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | NEWS | 5 | ||||
| -rw-r--r-- | elf/Makefile | 9 | ||||
| -rw-r--r-- | elf/pldd-xx.c | 238 | ||||
| -rw-r--r-- | elf/pldd.c | 234 |
5 files changed, 489 insertions, 3 deletions
@@ -1,3 +1,9 @@ +2011-06-09 Ulrich Drepper <drepper@gmail.com> + + * elf/Makefile: Add rules to build pldd. + * elf/pldd.c: New file. + * elf/pldd-xx.c: New file. + 2011-06-07 Ulrich Drepper <drepper@gmail.com> * version.h: Update for 2.15 development version. @@ -1,4 +1,4 @@ -GNU C Library NEWS -- history of user-visible changes. 2011-6-7 +GNU C Library NEWS -- history of user-visible changes. 2011-6-9 Copyright (C) 1992-2009, 2010, 2011 Free Software Foundation, Inc. See the end for copying conditions. @@ -6,6 +6,9 @@ Please send GNU C library bug reports via <http://sources.redhat.com/bugzilla/> using `glibc' in the "product" field. Version 2.15 + +* New program pldd to list loaded object of a process + Implemented by Ulrich Drepper. Version 2.14 diff --git a/elf/Makefile b/elf/Makefile index 6d314a9..844c9ca 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -150,8 +150,8 @@ install-others = $(inst_slibdir)/$(rtld-installed-name) install-bin-script = ldd endif -others = sprof sln -install-bin = sprof +others = sprof sln pldd +install-bin = sprof pldd others-static = sln install-rootsbin = sln @@ -164,6 +164,8 @@ install-rootsbin += ldconfig ldconfig-modules := cache readlib xmalloc xstrdup chroot_canon extra-objs += $(ldconfig-modules:=.o) +pldd-modules := xmalloc + # To find xmalloc.c and xstrdup.c vpath %.c ../locale/programs @@ -494,6 +496,9 @@ $(objpfx)ldd: ldd.bash.in $(common-objpfx)soversions.mk \ $(objpfx)sprof: $(libdl) $(objpfx)ldconfig: $(ldconfig-modules:%=$(objpfx)%.o) + +$(objpfx)pldd: $(pldd-modules:%=$(objpfx)%.o) + SYSCONF-FLAGS := -D'SYSCONFDIR="$(sysconfdir)"' CFLAGS-ldconfig.c = $(SYSCONF-FLAGS) -D'LIBDIR="$(libdir)"' \ -D'SLIBDIR="$(slibdir)"' -DIS_IN_ldconfig=1 diff --git a/elf/pldd-xx.c b/elf/pldd-xx.c new file mode 100644 index 0000000..0e3fcb7 --- /dev/null +++ b/elf/pldd-xx.c @@ -0,0 +1,238 @@ +/* Copyright (C) 2011 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@gmail.com>, 2011. + + 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#define E(name) E_(name, CLASS) +#define E_(name, cl) E__(name, cl) +#define E__(name, cl) name##cl +#define EW(type) EW_(Elf, CLASS, type) +#define EW_(e, w, t) EW__(e, w, _##t) +#define EW__(e, w, t) e##w##t + +#define static_assert(name, exp) \ + typedef int __assert_##name[((exp) != 0) - 1] + + +struct E(link_map) +{ + EW(Addr) l_addr; + EW(Addr) l_name; + EW(Addr) l_ld; + EW(Addr) l_next; + EW(Addr) l_prev; + EW(Addr) l_real; + Lmid_t l_ns; + EW(Addr) l_libname; +}; +#if CLASS == __ELF_NATIVE_CLASS +static_assert (l_addr, (offsetof (struct link_map, l_addr) + == offsetof (struct E(link_map), l_addr))); +static_assert (l_name, (offsetof (struct link_map, l_name) + == offsetof (struct E(link_map), l_name))); +static_assert (l_next, (offsetof (struct link_map, l_next) + == offsetof (struct E(link_map), l_next))); +#endif + + +struct E(libname_list) +{ + EW(Addr) name; + EW(Addr) next; +}; +#if CLASS == __ELF_NATIVE_CLASS +static_assert (name, (offsetof (struct libname_list, name) + == offsetof (struct E(libname_list), name))); +static_assert (next, (offsetof (struct libname_list, next) + == offsetof (struct E(libname_list), next))); +#endif + +struct E(r_debug) +{ + int r_version; + EW(Addr) r_map; +}; +#if CLASS == __ELF_NATIVE_CLASS +static_assert (r_version, (offsetof (struct r_debug, r_version) + == offsetof (struct E(r_debug), r_version))); +static_assert (r_map, (offsetof (struct r_debug, r_map) + == offsetof (struct E(r_debug), r_map))); +#endif + + +static int +E(find_maps) (pid_t pid, EW(Ehdr) *ehdr, void *auxv, size_t auxv_size) +{ + EW(Addr) phdr = 0; + unsigned int phnum = 0; + unsigned int phent = 0; + + EW(auxv_t) *auxvXX = (EW(auxv_t) *) auxv; + for (int i = 0; i < auxv_size / sizeof (EW(auxv_t)); ++i) + switch (auxvXX[i].a_type) + { + case AT_PHDR: + phdr = auxvXX[i].a_un.a_val; + break; + case AT_PHNUM: + phnum = auxvXX[i].a_un.a_val; + break; + case AT_PHENT: + phent = auxvXX[i].a_un.a_val; + break; + default: + break; + } + + if (phdr == 0 || phnum == 0 || phent == 0) + error (EXIT_FAILURE, 0, gettext ("cannot find program header of process")); + + EW(Phdr) *p = alloca (phnum * phent); + if (pread64 (memfd, p, phnum * phent, phdr) != phnum * phent) + { + error (0, 0, gettext ("cannot read program header")); + return EXIT_FAILURE; + } + + /* Determine the load offset. We need this for interpreting the + other program header entries so we do this in a separate loop. + Fortunately it is the first time unless someone does something + stupid when linking the application. */ + EW(Addr) offset = 0; + for (unsigned int i = 0; i < phnum; ++i) + if (p[i].p_type == PT_PHDR) + { + offset = phdr - p[i].p_vaddr; + break; + } + + EW(Addr) list = 0; + char *interp = NULL; + for (unsigned int i = 0; i < phnum; ++i) + if (p[i].p_type == PT_DYNAMIC) + { + EW(Dyn) *dyn = xmalloc (p[i].p_filesz); + if (pread64 (memfd, dyn, p[i].p_filesz, offset + p[i].p_vaddr) + != p[i].p_filesz) + { + error (0, 0, gettext ("cannot read dynamic section")); + return EXIT_FAILURE; + } + + /* Search for the DT_DEBUG entry. */ + for (unsigned int j = 0; j < p[i].p_filesz / sizeof (EW(Dyn)); ++j) + if (dyn[j].d_tag == DT_DEBUG && dyn[j].d_un.d_ptr != 0) + { + struct E(r_debug) r; + if (pread64 (memfd, &r, sizeof (r), dyn[j].d_un.d_ptr) + != sizeof (r)) + { + error (0, 0, gettext ("cannot read r_debug")); + return EXIT_FAILURE; + } + + if (r.r_map != 0) + { + list = r.r_map; + break; + } + } + + free (dyn); + break; + } + else if (p[i].p_type == PT_INTERP) + { + interp = alloca (p[i].p_filesz); + if (pread64 (memfd, interp, p[i].p_filesz, offset + p[i].p_vaddr) + != p[i].p_filesz) + { + error (0, 0, gettext ("cannot read program interpreter")); + return EXIT_FAILURE; + } + } + + if (list == 0) + { + if (interp == NULL) + { + // XXX check whether the executable itself is the loader + return EXIT_FAILURE; + } + + // XXX perhaps try finding ld.so and _r_debug in it + + return EXIT_FAILURE; + } + + /* Print the PID and program name first. */ + printf ("%lu:\t%s\n", (unsigned long int) pid, exe); + + /* Iterate over the list of objects and print the information. */ + size_t strsize = 256; + char *str = alloca (strsize); + do + { + struct E(link_map) m; + if (pread64 (memfd, &m, sizeof (m), list) != sizeof (m)) + { + error (0, 0, gettext ("cannot read link map")); + return EXIT_FAILURE; + } + + EW(Addr) name_offset = m.l_name; + again: + while (1) + { + ssize_t n = pread64 (memfd, str, strsize, name_offset); + if (n == -1) + { + error (0, 0, gettext ("cannot read object name")); + return EXIT_FAILURE; + } + + if (memchr (str, '\0', n) != NULL) + break; + + str = extend_alloca (str, strsize, strsize * 2); + } + + if (str[0] == '\0' && name_offset == m.l_name + && m.l_libname != 0) + { + /* Try the l_libname element. */ + struct E(libname_list) ln; + if (pread64 (memfd, &ln, sizeof (ln), m.l_libname) == sizeof (ln)) + { + name_offset = ln.name; + goto again; + } + } + + /* Skip over the executable. */ + if (str[0] != '\0') + printf ("%s\n", str); + + list = m.l_next; + } + while (list != 0); + + return 0; +} + + +#undef CLASS diff --git a/elf/pldd.c b/elf/pldd.c new file mode 100644 index 0000000..9fac19e --- /dev/null +++ b/elf/pldd.c @@ -0,0 +1,234 @@ +/* List dynamic shared objects linked into given process. + Copyright (C) 2011 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@gmail.com>, 2011. + + 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <alloca.h> +#include <argp.h> +#include <elf.h> +#include <errno.h> +#include <error.h> +#include <fcntl.h> +#include <libintl.h> +#include <link.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/ptrace.h> +#include <sys/stat.h> + +#include <ldsodefs.h> +#include <version.h> + +/* Global variables. */ +extern char *program_invocation_short_name; +#define PACKAGE _libc_intl_domainname + +/* External functions. */ +extern void *xmalloc (size_t n); +extern void *xrealloc (void *p, size_t n); + +/* Name and version of program. */ +static void print_version (FILE *stream, struct argp_state *state); +void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version; + +/* Bug report address. */ +const char *argp_program_bug_address = N_("\ +For bug reporting instructions, please see:\n\ +<http://www.gnu.org/software/libc/bugs.html>.\n"); + +/* Definitions of arguments for argp functions. */ +static const struct argp_option options[] = +{ + { NULL, 0, NULL, 0, NULL } +}; + +/* Short description of program. */ +static const char doc[] = N_("\ +List dynamic shared objects loaded into process."); + +/* Strings for arguments in help texts. */ +static const char args_doc[] = N_("PID"); + +/* Prototype for option handler. */ +static error_t parse_opt (int key, char *arg, struct argp_state *state); + +/* Data structure to communicate with argp functions. */ +static struct argp argp = +{ + options, parse_opt, args_doc, doc, NULL, NULL, NULL +}; + +// File descriptor of /proc/*/mem file. +static int memfd; + +/* Name of the executable */ +static char *exe; + +/* Local functions. */ +static int get_process_info (pid_t pid); + + +int +main (int argc, char *argv[]) +{ + /* Parse and process arguments. */ + int remaining; + argp_parse (&argp, argc, argv, 0, &remaining, NULL); + + if (remaining != argc - 1) + { + fprintf (stderr, + gettext ("Exactly one parameter with process ID required.\n")); + argp_help (&argp, stderr, ARGP_HELP_SEE, program_invocation_short_name); + return 1; + } + + char *endp; + errno = 0; + pid_t pid = strtoul (argv[remaining], &endp, 10); + if ((pid == ULONG_MAX && errno == ERANGE) || *endp != '\0') + error (EXIT_FAILURE, 0, gettext ("invalid process ID '%s'"), + argv[remaining]); + + /* Determine the program name. */ + char buf[11 + 3 * sizeof (pid)]; + snprintf (buf, sizeof (buf), "/proc/%lu/exe", (unsigned long int) pid); + size_t exesize = 1024; + exe = alloca (exesize); + ssize_t nexe; + while ((nexe = readlink (buf, exe, exesize)) == exesize) + extend_alloca (exe, exesize, 2 * exesize); + if (nexe == -1) + exe = (char *) "<program name undetermined>"; + else + exe[nexe] = '\0'; + + if (ptrace (PTRACE_ATTACH, pid, NULL, NULL) != 0) + error (EXIT_FAILURE, errno, gettext ("cannot attach to process %lu"), + (unsigned long int) pid); + + int status = get_process_info (pid); + + ptrace (PTRACE_DETACH, pid, NULL, NULL); + + return status; +} + + +/* Handle program arguments. */ +static error_t +parse_opt (int key, char *arg, struct argp_state *state) +{ + switch (key) + { + default: + return ARGP_ERR_UNKNOWN; + } + return 0; +} + + +/* Print the version information. */ +static void +print_version (FILE *stream, struct argp_state *state) +{ + fprintf (stream, "pldd (GNU %s) %s\n", PACKAGE, VERSION); + fprintf (stream, gettext ("\ +Copyright (C) %s Free Software Foundation, Inc.\n\ +This is free software; see the source for copying conditions. There is NO\n\ +warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\ +"), "2011"); + fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper"); +} + + +#define CLASS 32 +#include "pldd-xx.c" +#define CLASS 64 +#include "pldd-xx.c" + + +static int +get_process_info (pid_t pid) +{ + char buf[12 + 3 * sizeof (pid)]; + + snprintf (buf, sizeof (buf), "/proc/%lu/mem", (unsigned long int) pid); + memfd = open (buf, O_RDONLY); + if (memfd == -1) + goto no_info; + + snprintf (buf, sizeof (buf), "/proc/%lu/exe", (unsigned long int) pid); + int fd = open (buf, O_RDONLY); + if (fd == -1) + { + no_info: + error (0, errno, gettext ("cannot get information about process %lu"), + (unsigned long int) pid); + return EXIT_FAILURE; + } + + union + { + Elf32_Ehdr ehdr32; + Elf64_Ehdr ehdr64; + } uehdr; + if (read (fd, &uehdr, sizeof (uehdr)) != sizeof (uehdr)) + goto no_info; + + close (fd); + + if (memcmp (uehdr.ehdr32.e_ident, ELFMAG, SELFMAG) != 0) + { + error (0, 0, gettext ("process %lu is no ELF program"), + (unsigned long int) pid); + return EXIT_FAILURE; + } + + snprintf (buf, sizeof (buf), "/proc/%lu/auxv", (unsigned long int) pid); + fd = open (buf, O_RDONLY); + if (fd == -1) + goto no_info; + + size_t auxv_size = 0; + void *auxv = NULL; + while (1) + { + auxv_size += 512; + auxv = xrealloc (auxv, auxv_size); + + ssize_t n = read (fd, auxv, auxv_size); + if (n < 0) + goto no_info; + if (n < auxv_size) + { + auxv_size = n; + break; + } + } + + close (fd); + + if (uehdr.ehdr32.e_ident[EI_CLASS] == ELFCLASS32) + return find_maps32 (pid, &uehdr.ehdr32, auxv, auxv_size); + else + return find_maps64 (pid, &uehdr.ehdr64, auxv, auxv_size); +} |