+++ /dev/null
-/*
- * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
- * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com>
- *
- * SPDX-License-Identifier: GPL-2.0-only
- *
- */
-
-#define _LGPL_SOURCE
-#include <fcntl.h>
-#include <grp.h>
-#include <limits.h>
-#include <pwd.h>
-#include <sched.h>
-#include <signal.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <unistd.h>
-
-#include <common/bytecode/bytecode.h>
-#include <common/lttng-kernel.h>
-#include <common/common.h>
-#include <common/utils.h>
-#include <common/compat/errno.h>
-#include <common/compat/getenv.h>
-#include <common/compat/string.h>
-#include <common/unix.h>
-#include <common/defaults.h>
-#include <common/lttng-elf.h>
-#include <common/thread.h>
-
-#include <lttng/constant.h>
-
-#include <common/sessiond-comm/sessiond-comm.h>
-#include <common/filter/filter-ast.h>
-
-#include "runas.h"
-
-#define GETPW_BUFFER_FALLBACK_SIZE 4096
-
-struct run_as_data;
-struct run_as_ret;
-typedef int (*run_as_fct)(struct run_as_data *data, struct run_as_ret *ret_value);
-
-enum run_as_cmd {
- RUN_AS_MKDIR,
- RUN_AS_MKDIRAT,
- RUN_AS_MKDIR_RECURSIVE,
- RUN_AS_MKDIRAT_RECURSIVE,
- RUN_AS_OPEN,
- RUN_AS_OPENAT,
- RUN_AS_UNLINK,
- RUN_AS_UNLINKAT,
- RUN_AS_RMDIR,
- RUN_AS_RMDIRAT,
- RUN_AS_RMDIR_RECURSIVE,
- RUN_AS_RMDIRAT_RECURSIVE,
- RUN_AS_RENAME,
- RUN_AS_RENAMEAT,
- RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET,
- RUN_AS_EXTRACT_SDT_PROBE_OFFSETS,
- RUN_AS_GENERATE_FILTER_BYTECODE,
-};
-
-struct run_as_mkdir_data {
- int dirfd;
- char path[LTTNG_PATH_MAX];
- mode_t mode;
-} LTTNG_PACKED;
-
-struct run_as_open_data {
- int dirfd;
- char path[LTTNG_PATH_MAX];
- int flags;
- mode_t mode;
-} LTTNG_PACKED;
-
-struct run_as_unlink_data {
- int dirfd;
- char path[LTTNG_PATH_MAX];
-} LTTNG_PACKED;
-
-struct run_as_rmdir_data {
- int dirfd;
- char path[LTTNG_PATH_MAX];
- int flags; /* enum lttng_directory_handle_rmdir_recursive_flags. */
-} LTTNG_PACKED;
-
-struct run_as_extract_elf_symbol_offset_data {
- int fd;
- char function[LTTNG_SYMBOL_NAME_LEN];
-} LTTNG_PACKED;
-
-struct run_as_extract_sdt_probe_offsets_data {
- int fd;
- char probe_name[LTTNG_SYMBOL_NAME_LEN];
- char provider_name[LTTNG_SYMBOL_NAME_LEN];
-} LTTNG_PACKED;
-
-struct run_as_generate_filter_bytecode_data {
- char filter_expression[LTTNG_FILTER_MAX_LEN];
-} LTTNG_PACKED;
-
-struct run_as_rename_data {
- /*
- * [0] = old_dirfd
- * [1] = new_dirfd
- */
- int dirfds[2];
- char old_path[LTTNG_PATH_MAX];
- char new_path[LTTNG_PATH_MAX];
-} LTTNG_PACKED;
-
-struct run_as_open_ret {
- int fd;
-} LTTNG_PACKED;
-
-struct run_as_extract_elf_symbol_offset_ret {
- uint64_t offset;
-} LTTNG_PACKED;
-
-struct run_as_extract_sdt_probe_offsets_ret {
- uint32_t num_offset;
- uint64_t offsets[LTTNG_KERNEL_ABI_MAX_UPROBE_NUM];
-} LTTNG_PACKED;
-
-struct run_as_generate_filter_bytecode_ret {
- /* A lttng_bytecode_filter struct with 'dynamic' payload. */
- char bytecode[LTTNG_FILTER_MAX_LEN];
-} LTTNG_PACKED;
-
-struct run_as_data {
- enum run_as_cmd cmd;
- union {
- struct run_as_mkdir_data mkdir;
- struct run_as_open_data open;
- struct run_as_unlink_data unlink;
- struct run_as_rmdir_data rmdir;
- struct run_as_rename_data rename;
- struct run_as_extract_elf_symbol_offset_data extract_elf_symbol_offset;
- struct run_as_extract_sdt_probe_offsets_data extract_sdt_probe_offsets;
- struct run_as_generate_filter_bytecode_data generate_filter_bytecode;
- } u;
- uid_t uid;
- gid_t gid;
-} LTTNG_PACKED;
-
-/*
- * The run_as_ret structure holds the returned value and status of the command.
- *
- * The `u` union field holds the return value of the command; in most cases it
- * represents the success or the failure of the command. In more complex
- * commands, it holds a computed value.
- *
- * The _errno field is the errno recorded after the execution of the command.
- *
- * The _error fields is used the signify that return status of the command. For
- * simple commands returning `int` the _error field will be the same as the
- * ret_int field. In complex commands, it signify the success or failure of the
- * command.
- *
- */
-struct run_as_ret {
- union {
- int ret;
- struct run_as_open_ret open;
- struct run_as_extract_elf_symbol_offset_ret extract_elf_symbol_offset;
- struct run_as_extract_sdt_probe_offsets_ret extract_sdt_probe_offsets;
- struct run_as_generate_filter_bytecode_ret generate_filter_bytecode;
- } u;
- int _errno;
- bool _error;
-} LTTNG_PACKED;
-
-#define COMMAND_IN_FDS(data_ptr) ({ \
- int *fds = NULL; \
- if (command_properties[data_ptr->cmd].in_fds_offset != -1) { \
- fds = (int *) ((char *) data_ptr + command_properties[data_ptr->cmd].in_fds_offset); \
- } \
- fds; \
-})
-
-#define COMMAND_OUT_FDS(cmd, ret_ptr) ({ \
- int *fds = NULL; \
- if (command_properties[cmd].out_fds_offset != -1) { \
- fds = (int *) ((char *) ret_ptr + command_properties[cmd].out_fds_offset); \
- } \
- fds; \
-})
-
-#define COMMAND_IN_FD_COUNT(data_ptr) ({ \
- command_properties[data_ptr->cmd].in_fd_count; \
-})
-
-#define COMMAND_OUT_FD_COUNT(cmd) ({ \
- command_properties[cmd].out_fd_count; \
-})
-
-#define COMMAND_USE_CWD_FD(data_ptr) command_properties[data_ptr->cmd].use_cwd_fd
-
-struct run_as_command_properties {
- /* Set to -1 when not applicable. */
- ptrdiff_t in_fds_offset, out_fds_offset;
- unsigned int in_fd_count, out_fd_count;
- bool use_cwd_fd;
-};
-
-static const struct run_as_command_properties command_properties[] = {
- [RUN_AS_MKDIR] = {
- .in_fds_offset = offsetof(struct run_as_data, u.mkdir.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = true,
- },
- [RUN_AS_MKDIRAT] = {
- .in_fds_offset = offsetof(struct run_as_data, u.mkdir.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
- [RUN_AS_MKDIR_RECURSIVE] = {
- .in_fds_offset = offsetof(struct run_as_data, u.mkdir.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = true,
- },
- [RUN_AS_MKDIRAT_RECURSIVE] = {
- .in_fds_offset = offsetof(struct run_as_data, u.mkdir.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
- [RUN_AS_OPEN] = {
- .in_fds_offset = offsetof(struct run_as_data, u.open.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = offsetof(struct run_as_ret, u.open.fd),
- .out_fd_count = 1,
- .use_cwd_fd = true,
- },
- [RUN_AS_OPENAT] = {
- .in_fds_offset = offsetof(struct run_as_data, u.open.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = offsetof(struct run_as_ret, u.open.fd),
- .out_fd_count = 1,
- .use_cwd_fd = false,
- },
- [RUN_AS_UNLINK] = {
- .in_fds_offset = offsetof(struct run_as_data, u.unlink.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = true,
- },
- [RUN_AS_UNLINKAT] = {
- .in_fds_offset = offsetof(struct run_as_data, u.unlink.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
- [RUN_AS_RMDIR_RECURSIVE] = {
- .in_fds_offset = offsetof(struct run_as_data, u.rmdir.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = true,
- },
- [RUN_AS_RMDIRAT_RECURSIVE] = {
- .in_fds_offset = offsetof(struct run_as_data, u.rmdir.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
- [RUN_AS_RMDIR] = {
- .in_fds_offset = offsetof(struct run_as_data, u.rmdir.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = true,
- },
- [RUN_AS_RMDIRAT] = {
- .in_fds_offset = offsetof(struct run_as_data, u.rmdir.dirfd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
- [RUN_AS_RENAME] = {
- .in_fds_offset = offsetof(struct run_as_data, u.rename.dirfds),
- .in_fd_count = 2,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = true,
- },
- [RUN_AS_RENAMEAT] = {
- .in_fds_offset = offsetof(struct run_as_data, u.rename.dirfds),
- .in_fd_count = 2,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
- [RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET] = {
- .in_fds_offset = offsetof(struct run_as_data,
- u.extract_elf_symbol_offset.fd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
- [RUN_AS_EXTRACT_SDT_PROBE_OFFSETS] = {
- .in_fds_offset = offsetof(struct run_as_data,
- u.extract_sdt_probe_offsets.fd),
- .in_fd_count = 1,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
- [RUN_AS_GENERATE_FILTER_BYTECODE] = {
- .in_fds_offset = -1,
- .in_fd_count = 0,
- .out_fds_offset = -1,
- .out_fd_count = 0,
- .use_cwd_fd = false,
- },
-};
-
-struct run_as_worker {
- pid_t pid; /* Worker PID. */
- int sockpair[2];
- char *procname;
-};
-
-/* Single global worker per process (for now). */
-static struct run_as_worker *global_worker;
-/* Lock protecting the worker. */
-static pthread_mutex_t worker_lock = PTHREAD_MUTEX_INITIALIZER;
-
-#ifdef VALGRIND
-static
-int use_clone(void)
-{
- return 0;
-}
-#else
-static
-int use_clone(void)
-{
- return !lttng_secure_getenv("LTTNG_DEBUG_NOCLONE");
-}
-#endif
-
-/*
- * Create recursively directory using the FULL path.
- */
-static
-int _mkdirat_recursive(struct run_as_data *data, struct run_as_ret *ret_value)
-{
- const char *path;
- mode_t mode;
- struct lttng_directory_handle *handle;
-
- path = data->u.mkdir.path;
- mode = data->u.mkdir.mode;
-
- handle = lttng_directory_handle_create_from_dirfd(data->u.mkdir.dirfd);
- if (!handle) {
- ret_value->_errno = errno;
- ret_value->_error = true;
- ret_value->u.ret = -1;
- goto end;
- }
- /* Ownership of dirfd is transferred to the handle. */
- data->u.mkdir.dirfd = -1;
- /* Safe to call as we have transitioned to the requested uid/gid. */
- ret_value->u.ret = lttng_directory_handle_create_subdirectory_recursive(
- handle, path, mode);
- ret_value->_errno = errno;
- ret_value->_error = (ret_value->u.ret) ? true : false;
- lttng_directory_handle_put(handle);
-end:
- return ret_value->u.ret;
-}
-
-static
-int _mkdirat(struct run_as_data *data, struct run_as_ret *ret_value)
-{
- const char *path;
- mode_t mode;
- struct lttng_directory_handle *handle;
-
- path = data->u.mkdir.path;
- mode = data->u.mkdir.mode;
-
- handle = lttng_directory_handle_create_from_dirfd(data->u.mkdir.dirfd);
- if (!handle) {
- ret_value->u.ret = -1;
- ret_value->_errno = errno;
- ret_value->_error = true;
- goto end;
- }
- /* Ownership of dirfd is transferred to the handle. */
- data->u.mkdir.dirfd = -1;
- /* Safe to call as we have transitioned to the requested uid/gid. */
- ret_value->u.ret = lttng_directory_handle_create_subdirectory(
- handle, path, mode);
- ret_value->_errno = errno;
- ret_value->_error = (ret_value->u.ret) ? true : false;
- lttng_directory_handle_put(handle);
-end:
- return ret_value->u.ret;
-}
-
-static
-int _open(struct run_as_data *data, struct run_as_ret *ret_value)
-{
- int fd;
- struct lttng_directory_handle *handle;
-
- handle = lttng_directory_handle_create_from_dirfd(data->u.open.dirfd);
- if (!handle) {
- ret_value->_errno = errno;
- ret_value->_error = true;
- ret_value->u.ret = -1;
- goto end;
- }
- /* Ownership of dirfd is transferred to the handle. */
- data->u.open.dirfd = -1;
-
- fd = lttng_directory_handle_open_file(handle,
- data->u.open.path, data->u.open.flags,
- data->u.open.mode);
- if (fd < 0) {
- ret_value->u.ret = -1;
- ret_value->u.open.fd = -1;
- } else {
- ret_value->u.ret = 0;
- ret_value->u.open.fd = fd;
- }
-
- ret_value->_errno = errno;
- ret_value->_error = fd < 0;
- lttng_directory_handle_put(handle);
-end:
- return ret_value->u.ret;
-}
-
-static
-int _unlink(struct run_as_data *data, struct run_as_ret *ret_value)
-{
- struct lttng_directory_handle *handle;
-
- handle = lttng_directory_handle_create_from_dirfd(data->u.unlink.dirfd);
- if (!handle) {
- ret_value->u.ret = -1;
- ret_value->_errno = errno;
- ret_value->_error = true;
- goto end;
- }
-
- /* Ownership of dirfd is transferred to the handle. */
- data->u.unlink.dirfd = -1;
-
- ret_value->u.ret = lttng_directory_handle_unlink_file(handle,
- data->u.unlink.path);
- ret_value->_errno = errno;
- ret_value->_error = (ret_value->u.ret) ? true : false;
- lttng_directory_handle_put(handle);
-end:
- return ret_value->u.ret;
-}
-
-static
-int _rmdir(struct run_as_data *data, struct run_as_ret *ret_value)
-{
- struct lttng_directory_handle *handle;
-
- handle = lttng_directory_handle_create_from_dirfd(data->u.rmdir.dirfd);
- if (!handle) {
- ret_value->u.ret = -1;
- ret_value->_errno = errno;
- ret_value->_error = true;
- goto end;
- }
-
- /* Ownership of dirfd is transferred to the handle. */
- data->u.rmdir.dirfd = -1;
-
- ret_value->u.ret = lttng_directory_handle_remove_subdirectory(
- handle, data->u.rmdir.path);
- ret_value->_errno = errno;
- ret_value->_error = (ret_value->u.ret) ? true : false;
- lttng_directory_handle_put(handle);
-end:
- return ret_value->u.ret;
-}
-
-static
-int _rmdir_recursive(struct run_as_data *data, struct run_as_ret *ret_value)
-{
- struct lttng_directory_handle *handle;
-
- handle = lttng_directory_handle_create_from_dirfd(data->u.rmdir.dirfd);
- if (!handle) {
- ret_value->u.ret = -1;
- ret_value->_errno = errno;
- ret_value->_error = true;
- goto end;
- }
-
- /* Ownership of dirfd is transferred to the handle. */
- data->u.rmdir.dirfd = -1;
-
- ret_value->u.ret = lttng_directory_handle_remove_subdirectory_recursive(
- handle, data->u.rmdir.path, data->u.rmdir.flags);
- ret_value->_errno = errno;
- ret_value->_error = (ret_value->u.ret) ? true : false;
- lttng_directory_handle_put(handle);
-end:
- return ret_value->u.ret;
-}
-
-static
-int _rename(struct run_as_data *data, struct run_as_ret *ret_value)
-{
- const char *old_path, *new_path;
- struct lttng_directory_handle *old_handle = NULL, *new_handle = NULL;
-
- old_path = data->u.rename.old_path;
- new_path = data->u.rename.new_path;
-
- old_handle = lttng_directory_handle_create_from_dirfd(
- data->u.rename.dirfds[0]);
- if (!old_handle) {
- ret_value->u.ret = -1;
- goto end;
- }
- new_handle = lttng_directory_handle_create_from_dirfd(
- data->u.rename.dirfds[1]);
- if (!new_handle) {
- ret_value->u.ret = -1;
- goto end;
- }
-
- /* Ownership of dirfds are transferred to the handles. */
- data->u.rename.dirfds[0] = data->u.rename.dirfds[1] = -1;
-
- /* Safe to call as we have transitioned to the requested uid/gid. */
- ret_value->u.ret = lttng_directory_handle_rename(
- old_handle, old_path, new_handle, new_path);
-end:
- lttng_directory_handle_put(old_handle);
- lttng_directory_handle_put(new_handle);
- ret_value->_errno = errno;
- ret_value->_error = (ret_value->u.ret) ? true : false;
- return ret_value->u.ret;
-}
-
-#ifdef HAVE_ELF_H
-static
-int _extract_elf_symbol_offset(struct run_as_data *data,
- struct run_as_ret *ret_value)
-{
- int ret = 0;
- uint64_t offset;
-
- ret_value->_error = false;
- ret = lttng_elf_get_symbol_offset(data->u.extract_elf_symbol_offset.fd,
- data->u.extract_elf_symbol_offset.function,
- &offset);
- if (ret) {
- DBG("Failed to extract ELF function offset");
- ret_value->_error = true;
- }
- ret_value->u.extract_elf_symbol_offset.offset = offset;
-
- return ret;
-}
-
-static
-int _extract_sdt_probe_offsets(struct run_as_data *data,
- struct run_as_ret *ret_value)
-{
- int ret = 0;
- uint64_t *offsets = NULL;
- uint32_t num_offset;
-
- ret_value->_error = false;
-
- /* On success, this call allocates the offsets paramater. */
- ret = lttng_elf_get_sdt_probe_offsets(
- data->u.extract_sdt_probe_offsets.fd,
- data->u.extract_sdt_probe_offsets.provider_name,
- data->u.extract_sdt_probe_offsets.probe_name,
- &offsets, &num_offset);
-
- if (ret) {
- DBG("Failed to extract SDT probe offsets");
- ret_value->_error = true;
- goto end;
- }
-
- if (num_offset <= 0 || num_offset > LTTNG_KERNEL_ABI_MAX_UPROBE_NUM) {
- DBG("Wrong number of probes.");
- ret = -1;
- ret_value->_error = true;
- goto free_offset;
- }
-
- /* Copy the content of the offsets array to the ret struct. */
- memcpy(ret_value->u.extract_sdt_probe_offsets.offsets,
- offsets, num_offset * sizeof(uint64_t));
-
- ret_value->u.extract_sdt_probe_offsets.num_offset = num_offset;
-
-free_offset:
- free(offsets);
-end:
- return ret;
-}
-#else
-static
-int _extract_elf_symbol_offset(struct run_as_data *data,
- struct run_as_ret *ret_value)
-{
- ERR("Unimplemented runas command RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET");
- return -1;
-}
-
-static
-int _extract_sdt_probe_offsets(struct run_as_data *data,
- struct run_as_ret *ret_value)
-{
- ERR("Unimplemented runas command RUN_AS_EXTRACT_SDT_PROBE_OFFSETS");
- return -1;
-}
-#endif
-
-static
-int _generate_filter_bytecode(struct run_as_data *data,
- struct run_as_ret *ret_value) {
- int ret = 0;
- const char *filter_expression = NULL;
- struct filter_parser_ctx *ctx = NULL;
-
- ret_value->_error = false;
-
- filter_expression = data->u.generate_filter_bytecode.filter_expression;
-
- if (lttng_strnlen(filter_expression, LTTNG_FILTER_MAX_LEN - 1) == LTTNG_FILTER_MAX_LEN - 1) {
- ret_value->_error = true;
- ret = -1;
- goto end;
- }
-
- ret = filter_parser_ctx_create_from_filter_expression(filter_expression, &ctx);
- if (ret < 0) {
- ret_value->_error = true;
- ret = -1;
- goto end;
- }
-
- DBG("Size of bytecode generated: %u bytes.",
- bytecode_get_len(&ctx->bytecode->b));
-
- /* Copy the lttng_bytecode_filter object to the return structure. */
- memcpy(ret_value->u.generate_filter_bytecode.bytecode,
- &ctx->bytecode->b,
- sizeof(ctx->bytecode->b) +
- bytecode_get_len(&ctx->bytecode->b));
-
-end:
- if (ctx) {
- filter_bytecode_free(ctx);
- filter_ir_free(ctx);
- filter_parser_ctx_free(ctx);
- }
-
- return ret;
-}
-static
-run_as_fct run_as_enum_to_fct(enum run_as_cmd cmd)
-{
- switch (cmd) {
- case RUN_AS_MKDIR:
- case RUN_AS_MKDIRAT:
- return _mkdirat;
- case RUN_AS_MKDIR_RECURSIVE:
- case RUN_AS_MKDIRAT_RECURSIVE:
- return _mkdirat_recursive;
- case RUN_AS_OPEN:
- case RUN_AS_OPENAT:
- return _open;
- case RUN_AS_UNLINK:
- case RUN_AS_UNLINKAT:
- return _unlink;
- case RUN_AS_RMDIR:
- case RUN_AS_RMDIRAT:
- return _rmdir;
- case RUN_AS_RMDIR_RECURSIVE:
- case RUN_AS_RMDIRAT_RECURSIVE:
- return _rmdir_recursive;
- case RUN_AS_RENAME:
- case RUN_AS_RENAMEAT:
- return _rename;
- case RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET:
- return _extract_elf_symbol_offset;
- case RUN_AS_EXTRACT_SDT_PROBE_OFFSETS:
- return _extract_sdt_probe_offsets;
- case RUN_AS_GENERATE_FILTER_BYTECODE:
- return _generate_filter_bytecode;
- default:
- ERR("Unknown command %d", (int) cmd);
- return NULL;
- }
-}
-
-static
-int do_send_fds(int sock, const int *fds, unsigned int fd_count)
-{
- ssize_t len;
- unsigned int i;
-
- for (i = 0; i < fd_count; i++) {
- if (fds[i] < 0) {
- DBG("Attempt to send invalid file descriptor (fd = %i)",
- fds[i]);
- /* Return 0 as this is not a fatal error. */
- return 0;
- }
- }
-
- len = lttcomm_send_fds_unix_sock(sock, fds, fd_count);
- return len < 0 ? -1 : 0;
-}
-
-static
-int do_recv_fds(int sock, int *fds, unsigned int fd_count)
-{
- int ret = 0;
- unsigned int i;
- ssize_t len;
-
- len = lttcomm_recv_fds_unix_sock(sock, fds, fd_count);
- if (len == 0) {
- ret = -1;
- goto end;
- } else if (len < 0) {
- PERROR("Failed to receive file descriptors from socket");
- ret = -1;
- goto end;
- }
-
- for (i = 0; i < fd_count; i++) {
- if (fds[i] < 0) {
- ERR("Invalid file descriptor received from worker (fd = %i)", fds[i]);
- /* Return 0 as this is not a fatal error. */
- }
- }
-end:
- return ret;
-}
-
-static
-int send_fds_to_worker(const struct run_as_worker *worker,
- const struct run_as_data *data)
-{
- int ret = 0;
- unsigned int i;
-
- if (COMMAND_USE_CWD_FD(data) || COMMAND_IN_FD_COUNT(data) == 0) {
- goto end;
- }
-
- for (i = 0; i < COMMAND_IN_FD_COUNT(data); i++) {
- if (COMMAND_IN_FDS(data)[i] < 0) {
- ERR("Refusing to send invalid fd to worker (fd = %i)",
- COMMAND_IN_FDS(data)[i]);
- ret = -1;
- goto end;
- }
- }
-
- ret = do_send_fds(worker->sockpair[0], COMMAND_IN_FDS(data),
- COMMAND_IN_FD_COUNT(data));
- if (ret < 0) {
- PERROR("Failed to send file descriptor to run-as worker");
- ret = -1;
- goto end;
- }
-end:
- return ret;
-}
-
-static
-int send_fds_to_master(struct run_as_worker *worker, enum run_as_cmd cmd,
- struct run_as_ret *run_as_ret)
-{
- int ret = 0;
- unsigned int i;
-
- if (COMMAND_OUT_FD_COUNT(cmd) == 0) {
- goto end;
- }
-
- ret = do_send_fds(worker->sockpair[1], COMMAND_OUT_FDS(cmd, run_as_ret),
- COMMAND_OUT_FD_COUNT(cmd));
- if (ret < 0) {
- PERROR("Failed to send file descriptor to master process");
- goto end;
- }
-
- for (i = 0; i < COMMAND_OUT_FD_COUNT(cmd); i++) {
- int fd = COMMAND_OUT_FDS(cmd, run_as_ret)[i];
- if (fd >= 0) {
- int ret_close = close(fd);
-
- if (ret_close < 0) {
- PERROR("Failed to close result file descriptor (fd = %i)",
- fd);
- }
- }
- }
-end:
- return ret;
-}
-
-static
-int recv_fds_from_worker(const struct run_as_worker *worker, enum run_as_cmd cmd,
- struct run_as_ret *run_as_ret)
-{
- int ret = 0;
-
- if (COMMAND_OUT_FD_COUNT(cmd) == 0) {
- goto end;
- }
-
- ret = do_recv_fds(worker->sockpair[0], COMMAND_OUT_FDS(cmd, run_as_ret),
- COMMAND_OUT_FD_COUNT(cmd));
- if (ret < 0) {
- PERROR("Failed to receive file descriptor from run-as worker");
- ret = -1;
- }
-end:
- return ret;
-}
-
-static
-int recv_fds_from_master(struct run_as_worker *worker, struct run_as_data *data)
-{
- int ret = 0;
-
- if (COMMAND_USE_CWD_FD(data)) {
- unsigned int i;
-
- for (i = 0; i < COMMAND_IN_FD_COUNT(data); i++) {
- COMMAND_IN_FDS(data)[i] = AT_FDCWD;
- }
- goto end;
- }
-
- if (COMMAND_IN_FD_COUNT(data) == 0) {
- goto end;
- }
-
- ret = do_recv_fds(worker->sockpair[1], COMMAND_IN_FDS(data),
- COMMAND_IN_FD_COUNT(data));
- if (ret < 0) {
- PERROR("Failed to receive file descriptors from master process");
- ret = -1;
- }
-end:
- return ret;
-}
-
-static
-int cleanup_received_fds(struct run_as_data *data)
-{
- int ret = 0, i;
-
- for (i = 0; i < COMMAND_IN_FD_COUNT(data); i++) {
- if (COMMAND_IN_FDS(data)[i] == -1) {
- continue;
- }
- ret = close(COMMAND_IN_FDS(data)[i]);
- if (ret) {
- PERROR("Failed to close file descriptor received fd in run-as worker");
- goto end;
- }
- }
-end:
- return ret;
-}
-
-static int get_user_infos_from_uid(
- uid_t uid, char **username, gid_t *primary_gid)
-{
- int ret;
- char *buf = NULL;
- long raw_get_pw_buf_size;
- size_t get_pw_buf_size;
- struct passwd pwd;
- struct passwd *result = NULL;
-
- /* Fetch the max size for the temporary buffer. */
- errno = 0;
- raw_get_pw_buf_size = sysconf(_SC_GETPW_R_SIZE_MAX);
- if (raw_get_pw_buf_size < 0) {
- if (errno != 0) {
- PERROR("Failed to query _SC_GETPW_R_SIZE_MAX");
- goto error;
- }
-
- /* Limit is indeterminate. */
- WARN("Failed to query _SC_GETPW_R_SIZE_MAX as it is "
- "indeterminate; falling back to default buffer size");
- raw_get_pw_buf_size = GETPW_BUFFER_FALLBACK_SIZE;
- }
-
- get_pw_buf_size = (size_t) raw_get_pw_buf_size;
-
- buf = zmalloc(get_pw_buf_size);
- if (buf == NULL) {
- PERROR("Failed to allocate buffer to get password file entries");
- goto error;
- }
-
- ret = getpwuid_r(uid, &pwd, buf, get_pw_buf_size, &result);
- if (ret < 0) {
- PERROR("Failed to get user information for user: uid = %d",
- (int) uid);
- goto error;
- }
-
- if (result == NULL) {
- ERR("Failed to find user information in password entries: uid = %d",
- (int) uid);
- ret = -1;
- goto error;
- }
-
- *username = strdup(result->pw_name);
- if (*username == NULL) {
- PERROR("Failed to copy user name");
- goto error;
- }
-
- *primary_gid = result->pw_gid;
-
-end:
- free(buf);
- return ret;
-error:
- *username = NULL;
- *primary_gid = -1;
- ret = -1;
- goto end;
-}
-
-static int demote_creds(
- uid_t prev_uid, gid_t prev_gid, uid_t new_uid, gid_t new_gid)
-{
- int ret = 0;
- gid_t primary_gid;
- char *username = NULL;
-
- /* Change the group id. */
- if (prev_gid != new_gid) {
- ret = setegid(new_gid);
- if (ret < 0) {
- PERROR("Failed to set effective group id: new_gid = %d",
- (int) new_gid);
- goto end;
- }
- }
-
- /* Change the user id. */
- if (prev_uid != new_uid) {
- ret = get_user_infos_from_uid(new_uid, &username, &primary_gid);
- if (ret < 0) {
- goto end;
- }
-
- /*
- * Initialize the supplementary group access list.
- *
- * This is needed to handle cases where the supplementary groups
- * of the user the process is demoting-to would give it access
- * to a given file/folder, but not it's primary group.
- *
- * e.g
- * username: User1
- * Primary Group: User1
- * Secondary group: Disk, Network
- *
- * mkdir inside the following directory must work since User1
- * is part of the Network group.
- *
- * drwxrwx--- 2 root Network 4096 Jul 23 17:17 /tmp/my_folder/
- *
- *
- * The order of the following initgroups and seteuid calls is
- * important here;
- * Only a root process or one with CAP_SETGID capability can
- * call the the initgroups() function. We must initialize the
- * supplementary groups before we change the effective
- * UID to a less-privileged user.
- */
- ret = initgroups(username, primary_gid);
- if (ret < 0) {
- PERROR("Failed to init the supplementary group access list: "
- "username = `%s`, primary gid = %d", username,
- (int) primary_gid);
- goto end;
- }
-
- ret = seteuid(new_uid);
- if (ret < 0) {
- PERROR("Failed to set effective user id: new_uid = %d",
- (int) new_uid);
- goto end;
- }
- }
-end:
- free(username);
- return ret;
-}
-
-static int promote_creds(
- uid_t prev_uid, gid_t prev_gid, uid_t new_uid, gid_t new_gid)
-{
- int ret = 0;
- gid_t primary_gid;
- char *username = NULL;
-
- /* Change the group id. */
- if (prev_gid != new_gid) {
- ret = setegid(new_gid);
- if (ret < 0) {
- PERROR("Failed to set effective group id: new_gid = %d",
- (int) new_gid);
- goto end;
- }
- }
-
- /* Change the user id. */
- if (prev_uid != new_uid) {
- ret = get_user_infos_from_uid(new_uid, &username, &primary_gid);
- if (ret < 0) {
- goto end;
- }
-
- /*
- * seteuid call must be done before the initgroups call because
- * we need to be privileged (CAP_SETGID) to call initgroups().
- */
- ret = seteuid(new_uid);
- if (ret < 0) {
- PERROR("Failed to set effective user id: new_uid = %d",
- (int) new_uid);
- goto end;
- }
-
- /*
- * Initialize the supplementary group access list.
- *
- * There is a possibility the groups we set in the following
- * initgroups() call are not exactly the same as the ones we
- * had when we originally demoted. This can happen if the
- * /etc/group file is modified after the runas process is
- * forked. This is very unlikely.
- */
- ret = initgroups(username, primary_gid);
- if (ret < 0) {
- PERROR("Failed to init the supplementary group access "
- "list: username = `%s`, primary gid = %d",
- username, (int) primary_gid)
- goto end;
- }
- }
-end:
- free(username);
- return ret;
-}
-
-/*
- * Return < 0 on error, 0 if OK, 1 on hangup.
- */
-static
-int handle_one_cmd(struct run_as_worker *worker)
-{
- int ret = 0, promote_ret;
- struct run_as_data data = {};
- ssize_t readlen, writelen;
- struct run_as_ret sendret = {};
- run_as_fct cmd;
- const uid_t prev_ruid = getuid();
- const gid_t prev_rgid = getgid();
-
- /*
- * Stage 1: Receive run_as_data struct from the master.
- * The structure contains the command type and all the parameters needed for
- * its execution
- */
- readlen = lttcomm_recv_unix_sock(worker->sockpair[1], &data,
- sizeof(data));
- if (readlen == 0) {
- /* hang up */
- ret = 1;
- goto end;
- }
- if (readlen < sizeof(data)) {
- PERROR("lttcomm_recv_unix_sock error");
- ret = -1;
- goto end;
- }
-
- cmd = run_as_enum_to_fct(data.cmd);
- if (!cmd) {
- ret = -1;
- goto end;
- }
-
- /*
- * Stage 2: Receive file descriptor from master.
- * Some commands need a file descriptor as input so if it's needed we
- * receive the fd using the Unix socket.
- */
- ret = recv_fds_from_master(worker, &data);
- if (ret < 0) {
- PERROR("recv_fd_from_master error");
- ret = -1;
- goto end;
- }
-
- ret = demote_creds(prev_ruid, prev_rgid, data.uid, data.gid);
- if (ret < 0) {
- goto write_return;
- }
-
- /*
- * Also set umask to 0 for mkdir executable bit.
- */
- umask(0);
-
- /*
- * Stage 3: Execute the command
- */
- ret = (*cmd)(&data, &sendret);
- if (ret < 0) {
- DBG("Execution of command returned an error");
- }
-
-write_return:
- ret = cleanup_received_fds(&data);
- if (ret < 0) {
- ERR("Error cleaning up FD");
- goto promote_back;
- }
-
- /*
- * Stage 4: Send run_as_ret structure to the master.
- * This structure contain the return value of the command and the errno.
- */
- writelen = lttcomm_send_unix_sock(worker->sockpair[1], &sendret,
- sizeof(sendret));
- if (writelen < sizeof(sendret)) {
- PERROR("lttcomm_send_unix_sock error");
- ret = -1;
- goto promote_back;
- }
-
- /*
- * Stage 5: Send resulting file descriptors to the master.
- */
- ret = send_fds_to_master(worker, data.cmd, &sendret);
- if (ret < 0) {
- DBG("Sending FD to master returned an error");
- }
-
- ret = 0;
-
-promote_back:
- /* Return to previous uid/gid. */
- promote_ret = promote_creds(data.uid, data.gid, prev_ruid, prev_rgid);
- if (promote_ret < 0) {
- ERR("Failed to promote back to the initial credentials");
- }
-
-end:
- return ret;
-}
-
-static
-int run_as_worker(struct run_as_worker *worker)
-{
- int ret;
- ssize_t writelen;
- struct run_as_ret sendret;
- size_t proc_orig_len;
-
- /*
- * Initialize worker. Set a different process cmdline.
- */
- proc_orig_len = strlen(worker->procname);
- memset(worker->procname, 0, proc_orig_len);
- strncpy(worker->procname, DEFAULT_RUN_AS_WORKER_NAME, proc_orig_len);
-
- ret = lttng_thread_setname(DEFAULT_RUN_AS_WORKER_NAME);
- if (ret && ret != -ENOSYS) {
- /* Don't fail as this is not essential. */
- DBG("Failed to set pthread name attribute");
- }
-
- memset(&sendret, 0, sizeof(sendret));
-
- writelen = lttcomm_send_unix_sock(worker->sockpair[1], &sendret,
- sizeof(sendret));
- if (writelen < sizeof(sendret)) {
- PERROR("lttcomm_send_unix_sock error");
- ret = EXIT_FAILURE;
- goto end;
- }
-
- for (;;) {
- ret = handle_one_cmd(worker);
- if (ret < 0) {
- ret = EXIT_FAILURE;
- goto end;
- } else if (ret > 0) {
- break;
- } else {
- continue; /* Next command. */
- }
- }
- ret = EXIT_SUCCESS;
-end:
- return ret;
-}
-
-static
-int run_as_cmd(struct run_as_worker *worker,
- enum run_as_cmd cmd,
- struct run_as_data *data,
- struct run_as_ret *ret_value,
- uid_t uid, gid_t gid)
-{
- int ret = 0;
- ssize_t readlen, writelen;
-
- /*
- * If we are non-root, we can only deal with our own uid.
- */
- if (geteuid() != 0) {
- if (uid != geteuid()) {
- ret = -1;
- ret_value->_errno = EPERM;
- ERR("Client (%d)/Server (%d) UID mismatch (and sessiond is not root)",
- (int) uid, (int) geteuid());
- goto end;
- }
- }
-
- data->cmd = cmd;
- data->uid = uid;
- data->gid = gid;
-
- /*
- * Stage 1: Send the run_as_data struct to the worker process
- */
- writelen = lttcomm_send_unix_sock(worker->sockpair[0], data,
- sizeof(*data));
- if (writelen < sizeof(*data)) {
- PERROR("Error writing message to run_as");
- ret = -1;
- ret_value->_errno = EIO;
- goto end;
- }
-
- /*
- * Stage 2: Send file descriptor to the worker process if needed
- */
- ret = send_fds_to_worker(worker, data);
- if (ret) {
- PERROR("do_send_fd error");
- ret = -1;
- ret_value->_errno = EIO;
- goto end;
- }
-
- /*
- * Stage 3: Wait for the execution of the command
- */
-
- /*
- * Stage 4: Receive the run_as_ret struct containing the return value and
- * errno
- */
- readlen = lttcomm_recv_unix_sock(worker->sockpair[0], ret_value,
- sizeof(*ret_value));
- if (!readlen) {
- ERR("Run-as worker has hung-up during run_as_cmd");
- ret = -1;
- ret_value->_errno = EIO;
- goto end;
- } else if (readlen < sizeof(*ret_value)) {
- PERROR("Error reading response from run_as");
- ret = -1;
- ret_value->_errno = errno;
- goto end;
- }
-
- if (ret_value->_error) {
- /* Skip stage 5 on error as there will be no fd to receive. */
- goto end;
- }
-
- /*
- * Stage 5: Receive file descriptor if needed
- */
- ret = recv_fds_from_worker(worker, cmd, ret_value);
- if (ret < 0) {
- ERR("Error receiving fd");
- ret = -1;
- ret_value->_errno = EIO;
- }
-
-end:
- return ret;
-}
-
-/*
- * This is for debugging ONLY and should not be considered secure.
- */
-static
-int run_as_noworker(enum run_as_cmd cmd,
- struct run_as_data *data, struct run_as_ret *ret_value,
- uid_t uid, gid_t gid)
-{
- int ret, saved_errno;
- mode_t old_mask;
- run_as_fct fct;
-
- fct = run_as_enum_to_fct(cmd);
- if (!fct) {
- errno = -ENOSYS;
- ret = -1;
- goto end;
- }
- old_mask = umask(0);
- ret = fct(data, ret_value);
- saved_errno = ret_value->_errno;
- umask(old_mask);
- errno = saved_errno;
-end:
- return ret;
-}
-
-static
-int reset_sighandler(void)
-{
- int sig;
-
- DBG("Resetting run_as worker signal handlers to default");
- for (sig = 1; sig <= 31; sig++) {
- (void) signal(sig, SIG_DFL);
- }
- return 0;
-}
-
-static
-void worker_sighandler(int sig)
-{
- const char *signame;
-
- /*
- * The worker will inherit its parent's signals since they are part of
- * the same process group. However, in the case of SIGINT and SIGTERM,
- * we want to give the worker a chance to teardown gracefully when its
- * parent closes the command socket.
- */
- switch (sig) {
- case SIGINT:
- signame = "SIGINT";
- break;
- case SIGTERM:
- signame = "SIGTERM";
- break;
- default:
- signame = NULL;
- }
-
- if (signame) {
- DBG("run_as worker received signal %s", signame);
- } else {
- DBG("run_as_worker received signal %d", sig);
- }
-}
-
-static
-int set_worker_sighandlers(void)
-{
- int ret = 0;
- sigset_t sigset;
- struct sigaction sa;
-
- if ((ret = sigemptyset(&sigset)) < 0) {
- PERROR("sigemptyset");
- goto end;
- }
-
- sa.sa_handler = worker_sighandler;
- sa.sa_mask = sigset;
- sa.sa_flags = 0;
- if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
- PERROR("sigaction SIGINT");
- goto end;
- }
-
- if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
- PERROR("sigaction SIGTERM");
- goto end;
- }
-
- DBG("run_as signal handler set for SIGTERM and SIGINT");
-end:
- return ret;
-}
-
-static
-int run_as_create_worker_no_lock(const char *procname,
- post_fork_cleanup_cb clean_up_func,
- void *clean_up_user_data)
-{
- pid_t pid;
- int i, ret = 0;
- ssize_t readlen;
- struct run_as_ret recvret;
- struct run_as_worker *worker;
-
- LTTNG_ASSERT(!global_worker);
- if (!use_clone()) {
- /*
- * Don't initialize a worker, all run_as tasks will be performed
- * in the current process.
- */
- ret = 0;
- goto end;
- }
- worker = zmalloc(sizeof(*worker));
- if (!worker) {
- ret = -ENOMEM;
- goto end;
- }
- worker->procname = strdup(procname);
- if (!worker->procname) {
- ret = -ENOMEM;
- goto error_procname_alloc;
- }
- /* Create unix socket. */
- if (lttcomm_create_anon_unix_socketpair(worker->sockpair) < 0) {
- ret = -1;
- goto error_sock;
- }
-
- /* Fork worker. */
- pid = fork();
- if (pid < 0) {
- PERROR("fork");
- ret = -1;
- goto error_fork;
- } else if (pid == 0) {
- /* Child */
-
- reset_sighandler();
-
- set_worker_sighandlers();
-
- logger_set_thread_name("Run-as worker", true);
-
- if (clean_up_func) {
- if (clean_up_func(clean_up_user_data) < 0) {
- ERR("Run-as post-fork clean-up failed, exiting.");
- exit(EXIT_FAILURE);
- }
- }
-
- /* Just close, no shutdown. */
- if (close(worker->sockpair[0])) {
- PERROR("close");
- exit(EXIT_FAILURE);
- }
-
- /*
- * Close all FDs aside from STDIN, STDOUT, STDERR and sockpair[1]
- * Sockpair[1] is used as a control channel with the master
- */
- for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
- if (i != worker->sockpair[1]) {
- (void) close(i);
- }
- }
-
- worker->sockpair[0] = -1;
- ret = run_as_worker(worker);
- if (lttcomm_close_unix_sock(worker->sockpair[1])) {
- PERROR("close");
- ret = -1;
- }
- worker->sockpair[1] = -1;
- free(worker->procname);
- free(worker);
- LOG(ret ? PRINT_ERR : PRINT_DBG, "run_as worker exiting (ret = %d)", ret);
- exit(ret ? EXIT_FAILURE : EXIT_SUCCESS);
- } else {
- /* Parent */
-
- /* Just close, no shutdown. */
- if (close(worker->sockpair[1])) {
- PERROR("close");
- ret = -1;
- goto error_fork;
- }
- worker->sockpair[1] = -1;
- worker->pid = pid;
- /* Wait for worker to become ready. */
- readlen = lttcomm_recv_unix_sock(worker->sockpair[0],
- &recvret, sizeof(recvret));
- if (readlen < sizeof(recvret)) {
- ERR("readlen: %zd", readlen);
- PERROR("Error reading response from run_as at creation");
- ret = -1;
- goto error_fork;
- }
- global_worker = worker;
- }
-end:
- return ret;
-
- /* Error handling. */
-error_fork:
- for (i = 0; i < 2; i++) {
- if (worker->sockpair[i] < 0) {
- continue;
- }
- if (lttcomm_close_unix_sock(worker->sockpair[i])) {
- PERROR("close");
- }
- worker->sockpair[i] = -1;
- }
-error_sock:
- free(worker->procname);
-error_procname_alloc:
- free(worker);
- return ret;
-}
-
-static
-void run_as_destroy_worker_no_lock(void)
-{
- struct run_as_worker *worker = global_worker;
-
- DBG("Destroying run_as worker");
- if (!worker) {
- return;
- }
- /* Close unix socket */
- DBG("Closing run_as worker socket");
- if (lttcomm_close_unix_sock(worker->sockpair[0])) {
- PERROR("close");
- }
- worker->sockpair[0] = -1;
- /* Wait for worker. */
- for (;;) {
- int status;
- pid_t wait_ret;
-
- wait_ret = waitpid(worker->pid, &status, 0);
- if (wait_ret < 0) {
- if (errno == EINTR) {
- continue;
- }
- PERROR("waitpid");
- break;
- }
-
- if (WIFEXITED(status)) {
- LOG(WEXITSTATUS(status) == 0 ? PRINT_DBG : PRINT_ERR,
- DEFAULT_RUN_AS_WORKER_NAME " terminated with status code %d",
- WEXITSTATUS(status));
- break;
- } else if (WIFSIGNALED(status)) {
- ERR(DEFAULT_RUN_AS_WORKER_NAME " was killed by signal %d",
- WTERMSIG(status));
- break;
- }
- }
- free(worker->procname);
- free(worker);
- global_worker = NULL;
-}
-
-static
-int run_as_restart_worker(struct run_as_worker *worker)
-{
- int ret = 0;
- char *procname = NULL;
-
- procname = worker->procname;
-
- /* Close socket to run_as worker process and clean up the zombie process */
- run_as_destroy_worker_no_lock();
-
- /* Create a new run_as worker process*/
- ret = run_as_create_worker_no_lock(procname, NULL, NULL);
- if (ret < 0 ) {
- ERR("Restarting the worker process failed");
- ret = -1;
- goto err;
- }
-err:
- return ret;
-}
-
-static
-int run_as(enum run_as_cmd cmd, struct run_as_data *data,
- struct run_as_ret *ret_value, uid_t uid, gid_t gid)
-{
- int ret, saved_errno;
-
- pthread_mutex_lock(&worker_lock);
- if (use_clone()) {
- DBG("Using run_as worker");
-
- LTTNG_ASSERT(global_worker);
-
- ret = run_as_cmd(global_worker, cmd, data, ret_value, uid, gid);
- saved_errno = ret_value->_errno;
-
- /*
- * If the worker thread crashed the errno is set to EIO. we log
- * the error and start a new worker process.
- */
- if (ret == -1 && saved_errno == EIO) {
- DBG("Socket closed unexpectedly... "
- "Restarting the worker process");
- ret = run_as_restart_worker(global_worker);
- if (ret == -1) {
- ERR("Failed to restart worker process.");
- goto err;
- }
- }
- } else {
- DBG("Using run_as without worker");
- ret = run_as_noworker(cmd, data, ret_value, uid, gid);
- }
-err:
- pthread_mutex_unlock(&worker_lock);
- return ret;
-}
-
-int run_as_mkdir_recursive(const char *path, mode_t mode, uid_t uid, gid_t gid)
-{
- return run_as_mkdirat_recursive(AT_FDCWD, path, mode, uid, gid);
-}
-
-int run_as_mkdirat_recursive(int dirfd, const char *path, mode_t mode,
- uid_t uid, gid_t gid)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("mkdirat() recursive fd = %d%s, path = %s, mode = %d, uid = %d, gid = %d",
- dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "",
- path, (int) mode, (int) uid, (int) gid);
- ret = lttng_strncpy(data.u.mkdir.path, path,
- sizeof(data.u.mkdir.path));
- if (ret) {
- ERR("Failed to copy path argument of mkdirat recursive command");
- goto error;
- }
- data.u.mkdir.path[sizeof(data.u.mkdir.path) - 1] = '\0';
- data.u.mkdir.mode = mode;
- data.u.mkdir.dirfd = dirfd;
- run_as(dirfd == AT_FDCWD ? RUN_AS_MKDIR_RECURSIVE : RUN_AS_MKDIRAT_RECURSIVE,
- &data, &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- ret = run_as_ret.u.ret;
-error:
- return ret;
-}
-
-int run_as_mkdir(const char *path, mode_t mode, uid_t uid, gid_t gid)
-{
- return run_as_mkdirat(AT_FDCWD, path, mode, uid, gid);
-}
-
-int run_as_mkdirat(int dirfd, const char *path, mode_t mode,
- uid_t uid, gid_t gid)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("mkdirat() recursive fd = %d%s, path = %s, mode = %d, uid = %d, gid = %d",
- dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "",
- path, (int) mode, (int) uid, (int) gid);
- ret = lttng_strncpy(data.u.mkdir.path, path,
- sizeof(data.u.mkdir.path));
- if (ret) {
- ERR("Failed to copy path argument of mkdirat command");
- goto error;
- }
- data.u.mkdir.path[sizeof(data.u.mkdir.path) - 1] = '\0';
- data.u.mkdir.mode = mode;
- data.u.mkdir.dirfd = dirfd;
- run_as(dirfd == AT_FDCWD ? RUN_AS_MKDIR : RUN_AS_MKDIRAT,
- &data, &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- ret = run_as_ret.u.ret;
-error:
- return ret;
-}
-
-int run_as_open(const char *path, int flags, mode_t mode, uid_t uid,
- gid_t gid)
-{
- return run_as_openat(AT_FDCWD, path, flags, mode, uid, gid);
-}
-
-int run_as_openat(int dirfd, const char *path, int flags, mode_t mode,
- uid_t uid, gid_t gid)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("openat() fd = %d%s, path = %s, flags = %X, mode = %d, uid %d, gid %d",
- dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "",
- path, flags, (int) mode, (int) uid, (int) gid);
- ret = lttng_strncpy(data.u.open.path, path, sizeof(data.u.open.path));
- if (ret) {
- ERR("Failed to copy path argument of open command");
- goto error;
- }
- data.u.open.flags = flags;
- data.u.open.mode = mode;
- data.u.open.dirfd = dirfd;
- run_as(dirfd == AT_FDCWD ? RUN_AS_OPEN : RUN_AS_OPENAT,
- &data, &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- ret = run_as_ret.u.ret < 0 ? run_as_ret.u.ret :
- run_as_ret.u.open.fd;
-error:
- return ret;
-}
-
-int run_as_unlink(const char *path, uid_t uid, gid_t gid)
-{
- return run_as_unlinkat(AT_FDCWD, path, uid, gid);
-}
-
-int run_as_unlinkat(int dirfd, const char *path, uid_t uid, gid_t gid)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("unlinkat() fd = %d%s, path = %s, uid = %d, gid = %d",
- dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "",
- path, (int) uid, (int) gid);
- ret = lttng_strncpy(data.u.unlink.path, path,
- sizeof(data.u.unlink.path));
- if (ret) {
- goto error;
- }
- data.u.unlink.dirfd = dirfd;
- run_as(dirfd == AT_FDCWD ? RUN_AS_UNLINK : RUN_AS_UNLINKAT, &data,
- &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- ret = run_as_ret.u.ret;
-error:
- return ret;
-}
-
-int run_as_rmdir(const char *path, uid_t uid, gid_t gid)
-{
- return run_as_rmdirat(AT_FDCWD, path, uid, gid);
-}
-
-int run_as_rmdirat(int dirfd, const char *path, uid_t uid, gid_t gid)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("rmdirat() fd = %d%s, path = %s, uid = %d, gid = %d",
- dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "",
- path, (int) uid, (int) gid);
- ret = lttng_strncpy(data.u.rmdir.path, path,
- sizeof(data.u.rmdir.path));
- if (ret) {
- goto error;
- }
- data.u.rmdir.dirfd = dirfd;
- run_as(dirfd == AT_FDCWD ? RUN_AS_RMDIR : RUN_AS_RMDIRAT, &data,
- &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- ret = run_as_ret.u.ret;
-error:
- return ret;
-}
-
-int run_as_rmdir_recursive(const char *path, uid_t uid, gid_t gid, int flags)
-{
- return run_as_rmdirat_recursive(AT_FDCWD, path, uid, gid, flags);
-}
-
-int run_as_rmdirat_recursive(int dirfd, const char *path, uid_t uid, gid_t gid, int flags)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("rmdirat() recursive fd = %d%s, path = %s, uid = %d, gid = %d",
- dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "",
- path, (int) uid, (int) gid);
- ret = lttng_strncpy(data.u.rmdir.path, path,
- sizeof(data.u.rmdir.path));
- if (ret) {
- goto error;
- }
- data.u.rmdir.dirfd = dirfd;
- data.u.rmdir.flags = flags;
- run_as(dirfd == AT_FDCWD ? RUN_AS_RMDIR_RECURSIVE : RUN_AS_RMDIRAT_RECURSIVE,
- &data, &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- ret = run_as_ret.u.ret;
-error:
- return ret;
-}
-
-int run_as_rename(const char *old, const char *new, uid_t uid, gid_t gid)
-{
- return run_as_renameat(AT_FDCWD, old, AT_FDCWD, new, uid, gid);
-}
-
-int run_as_renameat(int old_dirfd, const char *old_name,
- int new_dirfd, const char *new_name, uid_t uid, gid_t gid)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("renameat() old_dirfd = %d%s, old_name = %s, new_dirfd = %d%s, new_name = %s, uid = %d, gid = %d",
- old_dirfd, old_dirfd == AT_FDCWD ? " (AT_FDCWD)" : "",
- old_name,
- new_dirfd, new_dirfd == AT_FDCWD ? " (AT_FDCWD)" : "",
- new_name, (int) uid, (int) gid);
- ret = lttng_strncpy(data.u.rename.old_path, old_name,
- sizeof(data.u.rename.old_path));
- if (ret) {
- goto error;
- }
- ret = lttng_strncpy(data.u.rename.new_path, new_name,
- sizeof(data.u.rename.new_path));
- if (ret) {
- goto error;
- }
-
- data.u.rename.dirfds[0] = old_dirfd;
- data.u.rename.dirfds[1] = new_dirfd;
- run_as(old_dirfd == AT_FDCWD && new_dirfd == AT_FDCWD ?
- RUN_AS_RENAME : RUN_AS_RENAMEAT,
- &data, &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- ret = run_as_ret.u.ret;
-error:
- return ret;
-}
-
-int run_as_extract_elf_symbol_offset(int fd, const char* function,
- uid_t uid, gid_t gid, uint64_t *offset)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("extract_elf_symbol_offset() on fd=%d and function=%s "
- "with for uid %d and gid %d", fd, function,
- (int) uid, (int) gid);
-
- data.u.extract_elf_symbol_offset.fd = fd;
-
- strncpy(data.u.extract_elf_symbol_offset.function, function, LTTNG_SYMBOL_NAME_LEN - 1);
- data.u.extract_elf_symbol_offset.function[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
- ret = lttng_strncpy(data.u.extract_elf_symbol_offset.function,
- function,
- sizeof(data.u.extract_elf_symbol_offset.function));
- if (ret) {
- goto error;
- }
-
- run_as(RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET, &data, &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- if (run_as_ret._error) {
- ret = -1;
- goto error;
- }
-
- *offset = run_as_ret.u.extract_elf_symbol_offset.offset;
-error:
- return ret;
-}
-
-int run_as_extract_sdt_probe_offsets(int fd, const char* provider_name,
- const char* probe_name, uid_t uid, gid_t gid,
- uint64_t **offsets, uint32_t *num_offset)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
-
- DBG3("extract_sdt_probe_offsets() on fd=%d, probe_name=%s and "
- "provider_name=%s with for uid %d and gid %d", fd,
- probe_name, provider_name, (int) uid, (int) gid);
-
- data.u.extract_sdt_probe_offsets.fd = fd;
-
- ret = lttng_strncpy(data.u.extract_sdt_probe_offsets.probe_name, probe_name,
- sizeof(data.u.extract_sdt_probe_offsets.probe_name));
- if (ret) {
- goto error;
- }
- ret = lttng_strncpy(data.u.extract_sdt_probe_offsets.provider_name,
- provider_name,
- sizeof(data.u.extract_sdt_probe_offsets.provider_name));
- if (ret) {
- goto error;
- }
-
- run_as(RUN_AS_EXTRACT_SDT_PROBE_OFFSETS, &data, &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- if (run_as_ret._error) {
- ret = -1;
- goto error;
- }
-
- *num_offset = run_as_ret.u.extract_sdt_probe_offsets.num_offset;
- *offsets = zmalloc(*num_offset * sizeof(uint64_t));
- if (!*offsets) {
- ret = -ENOMEM;
- goto error;
- }
-
- memcpy(*offsets, run_as_ret.u.extract_sdt_probe_offsets.offsets,
- *num_offset * sizeof(uint64_t));
-error:
- return ret;
-}
-
-int run_as_generate_filter_bytecode(const char *filter_expression,
- const struct lttng_credentials *creds,
- struct lttng_bytecode **bytecode)
-{
- int ret;
- struct run_as_data data = {};
- struct run_as_ret run_as_ret = {};
- const struct lttng_bytecode *view_bytecode = NULL;
- struct lttng_bytecode *local_bytecode = NULL;
- const uid_t uid = lttng_credentials_get_uid(creds);
- const gid_t gid = lttng_credentials_get_gid(creds);
-
- DBG3("generate_filter_bytecode() from expression=\"%s\" for uid %d and gid %d",
- filter_expression, (int) uid, (int) gid);
-
- ret = lttng_strncpy(data.u.generate_filter_bytecode.filter_expression, filter_expression,
- sizeof(data.u.generate_filter_bytecode.filter_expression));
- if (ret) {
- goto error;
- }
-
- run_as(RUN_AS_GENERATE_FILTER_BYTECODE, &data, &run_as_ret, uid, gid);
- errno = run_as_ret._errno;
- if (run_as_ret._error) {
- ret = -1;
- goto error;
- }
-
- view_bytecode = (const struct lttng_bytecode *) run_as_ret.u.generate_filter_bytecode.bytecode;
-
- local_bytecode = zmalloc(sizeof(*local_bytecode) + view_bytecode->len);
- if (!local_bytecode) {
- ret = -ENOMEM;
- goto error;
- }
-
- memcpy(local_bytecode, run_as_ret.u.generate_filter_bytecode.bytecode,
- sizeof(*local_bytecode) + view_bytecode->len);
- *bytecode = local_bytecode;
-error:
- return ret;
-}
-
-int run_as_create_worker(const char *procname,
- post_fork_cleanup_cb clean_up_func,
- void *clean_up_user_data)
-{
- int ret;
-
- pthread_mutex_lock(&worker_lock);
- ret = run_as_create_worker_no_lock(procname, clean_up_func,
- clean_up_user_data);
- pthread_mutex_unlock(&worker_lock);
- return ret;
-}
-
-void run_as_destroy_worker(void)
-{
- pthread_mutex_lock(&worker_lock);
- run_as_destroy_worker_no_lock();
- pthread_mutex_unlock(&worker_lock);
-}
projects / lttng-tools.git / blobdiff