X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Frunas.c;fp=src%2Fcommon%2Frunas.c;h=0000000000000000000000000000000000000000;hp=930c973ff956ec2c13aeed57d2d2d69b8995775f;hb=a6bc4ca9d659caf016ef932fcd944029737ac57c;hpb=97535efaa975ca52bf02c2d5e76351bfd2e3defa diff --git a/src/common/runas.c b/src/common/runas.c deleted file mode 100644 index 930c973ff..000000000 --- a/src/common/runas.c +++ /dev/null @@ -1,2033 +0,0 @@ -/* - * Copyright (C) 2011 David Goulet - * Copyright (C) 2011 Mathieu Desnoyers - * Copyright (C) 2019 Jérémie Galarneau - * - * SPDX-License-Identifier: GPL-2.0-only - * - */ - -#define _LGPL_SOURCE -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include - -#include -#include - -#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); -}