X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Frunas.c;h=28bcff30a5c550ba7800f2b74aa249362d0c24ec;hp=7a6be2837d688ec2829a706d83f4153657464dfe;hb=55cb0d6f5c8f1b793b0ed66cb4aaa7d18c612c36;hpb=0452bf084c6d8416b88c2bb941e99eb4eec453b8 diff --git a/src/common/runas.c b/src/common/runas.c index 7a6be2837..28bcff30a 100644 --- a/src/common/runas.c +++ b/src/common/runas.c @@ -1,19 +1,10 @@ /* - * Copyright (C) 2011 - David Goulet - * Mathieu Desnoyers + * Copyright (C) 2011 David Goulet + * Copyright (C) 2011 Mathieu Desnoyers + * Copyright (C) 2019 Jérémie Galarneau * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License, version 2 only, - * as published by the Free Software Foundation. + * SPDX-License-Identifier: GPL-2.0-only * - * This program is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for - * more details. - * - * You should have received a copy of the GNU General Public License along - * with this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #define _LGPL_SOURCE @@ -32,44 +23,99 @@ #include #include +#include #include #include #include #include #include #include +#include + +#include #include "runas.h" struct run_as_data; -typedef int (*run_as_fct)(struct run_as_data *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, +}; struct run_as_mkdir_data { - char path[PATH_MAX]; + int dirfd; + char path[LTTNG_PATH_MAX]; mode_t mode; -}; +} LTTNG_PACKED; struct run_as_open_data { - char path[PATH_MAX]; + int dirfd; + char path[LTTNG_PATH_MAX]; int flags; mode_t mode; -}; +} LTTNG_PACKED; struct run_as_unlink_data { - char path[PATH_MAX]; -}; + 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_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_rmdir_recursive_data { - char path[PATH_MAX]; -}; +struct run_as_open_ret { + int fd; +} LTTNG_PACKED; -enum run_as_cmd { - RUN_AS_MKDIR, - RUN_AS_OPEN, - RUN_AS_UNLINK, - RUN_AS_RMDIR_RECURSIVE, - RUN_AS_MKDIR_RECURSIVE, -}; +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_MAX_UPROBE_NUM]; +} LTTNG_PACKED; struct run_as_data { enum run_as_cmd cmd; @@ -77,15 +123,189 @@ struct run_as_data { struct run_as_mkdir_data mkdir; struct run_as_open_data open; struct run_as_unlink_data unlink; - struct run_as_rmdir_recursive_data rmdir_recursive; + 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; } 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 { - int 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; + } 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, + }, }; struct run_as_worker { @@ -113,63 +333,321 @@ int use_clone(void) } #endif -LTTNG_HIDDEN -int _utils_mkdir_recursive_unsafe(const char *path, mode_t mode); - /* * Create recursively directory using the FULL path. */ static -int _mkdir_recursive(struct run_as_data *data) +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. */ - return _utils_mkdir_recursive_unsafe(path, mode); + 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 _mkdir(struct run_as_data *data) +int _open(struct run_as_data *data, struct run_as_ret *ret_value) { - return mkdir(data->u.mkdir.path, data->u.mkdir.mode); + 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 _open(struct run_as_data *data) +int _unlink(struct run_as_data *data, struct run_as_ret *ret_value) { - return open(data->u.open.path, data->u.open.flags, data->u.open.mode); + 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 _unlink(struct run_as_data *data) +int _rmdir(struct run_as_data *data, struct run_as_ret *ret_value) { - return unlink(data->u.unlink.path); + 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) +int _rmdir_recursive(struct run_as_data *data, struct run_as_ret *ret_value) { - return utils_recursive_rmdir(data->u.rmdir_recursive.path); + 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_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 run_as_fct run_as_enum_to_fct(enum run_as_cmd cmd) { switch (cmd) { case RUN_AS_MKDIR: - return _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_MKDIR_RECURSIVE: - return _mkdir_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; default: ERR("Unknown command %d", (int) cmd); return NULL; @@ -177,55 +655,172 @@ run_as_fct run_as_enum_to_fct(enum run_as_cmd cmd) } static -int do_send_fd(struct run_as_worker *worker, - enum run_as_cmd cmd, int fd) +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) { + ERR("Attempt to send invalid file descriptor to master (fd = %i)", + fds[i]); + /* Return 0 as this is not a fatal error. */ + return 0; + } + } - switch (cmd) { - case RUN_AS_OPEN: - break; - default: - 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; } - if (fd < 0) { - return 0; + + 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. */ + } } - len = lttcomm_send_fds_unix_sock(worker->sockpair[1], &fd, 1); - if (len < 0) { - PERROR("lttcomm_send_fds_unix_sock"); - return -1; +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; } - if (close(fd) < 0) { - PERROR("close"); - return -1; + + 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; + } } - return 0; + + 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 do_recv_fd(struct run_as_worker *worker, - enum run_as_cmd cmd, int *fd) +int send_fds_to_master(struct run_as_worker *worker, enum run_as_cmd cmd, + struct run_as_ret *run_as_ret) { - ssize_t len; + int ret = 0; + unsigned int i; - switch (cmd) { - case RUN_AS_OPEN: - break; - default: - return 0; + if (COMMAND_OUT_FD_COUNT(cmd) == 0) { + goto end; } - if (*fd < 0) { - return 0; + + 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; } - len = lttcomm_recv_fds_unix_sock(worker->sockpair[0], fd, 1); - if (!len) { - return -1; - } else if (len < 0) { - PERROR("lttcomm_recv_fds_unix_sock"); - return -1; + + for (i = 0; i < COMMAND_OUT_FD_COUNT(cmd); i++) { + int ret_close = close(COMMAND_OUT_FDS(cmd, run_as_ret)[i]); + + if (ret_close < 0) { + PERROR("Failed to close result file descriptor"); + } } - return 0; +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; + } + + 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; } /* @@ -235,13 +830,17 @@ static int handle_one_cmd(struct run_as_worker *worker) { int ret = 0; - struct run_as_data data; + struct run_as_data data = {}; ssize_t readlen, writelen; - struct run_as_ret sendret; + struct run_as_ret sendret = {}; run_as_fct cmd; uid_t prev_euid; - /* Read data */ + /* + * 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) { @@ -261,10 +860,24 @@ int handle_one_cmd(struct run_as_worker *worker) 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; + } + prev_euid = getuid(); if (data.gid != getegid()) { ret = setegid(data.gid); if (ret < 0) { + sendret._error = true; + sendret._errno = errno; PERROR("setegid"); goto write_return; } @@ -272,20 +885,37 @@ int handle_one_cmd(struct run_as_worker *worker) if (data.uid != prev_euid) { ret = seteuid(data.uid); if (ret < 0) { + sendret._error = true; + sendret._errno = errno; PERROR("seteuid"); goto write_return; } } + /* * Also set umask to 0 for mkdir executable bit. */ umask(0); - ret = (*cmd)(&data); + + /* + * Stage 3: Execute the command + */ + ret = (*cmd)(&data, &sendret); + if (ret < 0) { + DBG("Execution of command returned an error"); + } write_return: - sendret.ret = ret; - sendret._errno = errno; - /* send back return value */ + ret = cleanup_received_fds(&data); + if (ret < 0) { + ERR("Error cleaning up FD"); + goto end; + } + + /* + * 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)) { @@ -293,12 +923,16 @@ write_return: ret = -1; goto end; } - ret = do_send_fd(worker, data.cmd, ret); - if (ret) { - PERROR("do_send_fd error"); - ret = -1; + + /* + * 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"); goto end; } + if (seteuid(prev_euid) < 0) { PERROR("seteuid"); ret = -1; @@ -329,11 +963,10 @@ int run_as_worker(struct run_as_worker *worker) if (ret && ret != -ENOSYS) { /* Don't fail as this is not essential. */ PERROR("prctl PR_SET_NAME"); - ret = 0; } - sendret.ret = 0; - sendret._errno = 0; + memset(&sendret, 0, sizeof(sendret)); + writelen = lttcomm_send_unix_sock(worker->sockpair[1], &sendret, sizeof(sendret)); if (writelen < sizeof(sendret)) { @@ -362,18 +995,19 @@ 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; - struct run_as_ret recvret; /* * If we are non-root, we can only deal with our own uid. */ if (geteuid() != 0) { if (uid != geteuid()) { - recvret.ret = -1; - recvret._errno = EPERM; + ret = -1; + ret_value->_errno = EPERM; ERR("Client (%d)/Server (%d) UID mismatch (and sessiond is not root)", (int) uid, (int) geteuid()); goto end; @@ -384,149 +1018,95 @@ int run_as_cmd(struct run_as_worker *worker, 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"); - recvret.ret = -1; - recvret._errno = errno; + ret = -1; + ret_value->_errno = EIO; goto end; } - /* receive return value */ - readlen = lttcomm_recv_unix_sock(worker->sockpair[0], &recvret, - sizeof(recvret)); - if (!readlen) { - ERR("Run-as worker has hung-up during run_as_cmd"); - recvret.ret = -1; - recvret._errno = EIO; + /* + * 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; - } else if (readlen < sizeof(recvret)) { - PERROR("Error reading response from run_as"); - recvret.ret = -1; - recvret._errno = errno; - } - if (do_recv_fd(worker, cmd, &recvret.ret)) { - recvret.ret = -1; - recvret._errno = EIO; } -end: - errno = recvret._errno; - return recvret.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, uid_t uid, gid_t gid) -{ - int ret, saved_errno; - mode_t old_mask; - run_as_fct fct; + /* + * Stage 3: Wait for the execution of the command + */ - fct = run_as_enum_to_fct(cmd); - if (!fct) { - errno = -ENOSYS; + /* + * 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; - } - old_mask = umask(0); - ret = fct(data); - saved_errno = errno; - umask(old_mask); - errno = saved_errno; -end: - return ret; -} - -static -int run_as(enum run_as_cmd cmd, struct run_as_data *data, uid_t uid, gid_t gid) -{ - int ret; - - if (use_clone()) { - DBG("Using run_as worker"); - pthread_mutex_lock(&worker_lock); - assert(global_worker); - ret = run_as_cmd(global_worker, cmd, data, uid, gid); - pthread_mutex_unlock(&worker_lock); - - } else { - DBG("Using run_as without worker"); - ret = run_as_noworker(cmd, data, uid, gid); - } - return ret; -} - -LTTNG_HIDDEN -int run_as_mkdir_recursive(const char *path, mode_t mode, uid_t uid, gid_t gid) -{ - struct run_as_data data; - - DBG3("mkdir() recursive %s with mode %d for uid %d and gid %d", - path, (int) mode, (int) uid, (int) gid); - strncpy(data.u.mkdir.path, path, PATH_MAX - 1); - data.u.mkdir.path[PATH_MAX - 1] = '\0'; - data.u.mkdir.mode = mode; - return run_as(RUN_AS_MKDIR_RECURSIVE, &data, uid, gid); -} - -LTTNG_HIDDEN -int run_as_mkdir(const char *path, mode_t mode, uid_t uid, gid_t gid) -{ - struct run_as_data data; - - DBG3("mkdir() %s with mode %d for uid %d and gid %d", - path, (int) mode, (int) uid, (int) gid); - strncpy(data.u.mkdir.path, path, PATH_MAX - 1); - data.u.mkdir.path[PATH_MAX - 1] = '\0'; - data.u.mkdir.mode = mode; - return run_as(RUN_AS_MKDIR, &data, uid, gid); -} - -/* - * Note: open_run_as is currently not working. We'd need to pass the fd - * opened in the child to the parent. - */ -LTTNG_HIDDEN -int run_as_open(const char *path, int flags, mode_t mode, uid_t uid, gid_t gid) -{ - struct run_as_data data; + } else if (readlen < sizeof(*ret_value)) { + PERROR("Error reading response from run_as"); + ret = -1; + ret_value->_errno = errno; + goto end; + } - DBG3("open() %s with flags %X mode %d for uid %d and gid %d", - path, flags, (int) mode, (int) uid, (int) gid); - strncpy(data.u.open.path, path, PATH_MAX - 1); - data.u.open.path[PATH_MAX - 1] = '\0'; - data.u.open.flags = flags; - data.u.open.mode = mode; - return run_as(RUN_AS_OPEN, &data, uid, gid); -} + if (ret_value->_error) { + /* Skip stage 5 on error as there will be no fd to receive. */ + goto end; + } -LTTNG_HIDDEN -int run_as_unlink(const char *path, uid_t uid, gid_t gid) -{ - struct run_as_data data; + /* + * 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; + } - DBG3("unlink() %s with for uid %d and gid %d", - path, (int) uid, (int) gid); - strncpy(data.u.unlink.path, path, PATH_MAX - 1); - data.u.unlink.path[PATH_MAX - 1] = '\0'; - return run_as(RUN_AS_UNLINK, &data, uid, gid); +end: + return ret; } -LTTNG_HIDDEN -int run_as_rmdir_recursive(const char *path, uid_t uid, gid_t gid) +/* + * 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) { - struct run_as_data data; + int ret, saved_errno; + mode_t old_mask; + run_as_fct fct; - DBG3("rmdir_recursive() %s with for uid %d and gid %d", - path, (int) uid, (int) gid); - strncpy(data.u.rmdir_recursive.path, path, PATH_MAX - 1); - data.u.rmdir_recursive.path[PATH_MAX - 1] = '\0'; - return run_as(RUN_AS_RMDIR_RECURSIVE, &data, uid, gid); + 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 @@ -547,10 +1127,10 @@ void worker_sighandler(int sig) const char *signame; /* - * The worker will 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. + * 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: @@ -560,10 +1140,14 @@ void worker_sighandler(int sig) signame = "SIGTERM"; break; default: - signame = "Unknown"; + signame = NULL; } - DBG("run_as worker received signal %s", signame); + if (signame) { + DBG("run_as worker received signal %s", signame); + } else { + DBG("run_as_worker received signal %d", sig); + } } static @@ -596,8 +1180,10 @@ end: return ret; } -LTTNG_HIDDEN -int run_as_create_worker(char *procname) +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; @@ -605,7 +1191,6 @@ int run_as_create_worker(char *procname) struct run_as_ret recvret; struct run_as_worker *worker; - pthread_mutex_lock(&worker_lock); assert(!global_worker); if (!use_clone()) { /* @@ -620,12 +1205,17 @@ int run_as_create_worker(char *procname) ret = -ENOMEM; goto end; } - worker->procname = procname; + 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) { @@ -638,14 +1228,29 @@ int run_as_create_worker(char *procname) reset_sighandler(); set_worker_sighandlers(); + 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); + } + } - /* The child has no use for this lock. */ - pthread_mutex_unlock(&worker_lock); /* 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])) { @@ -653,6 +1258,8 @@ int run_as_create_worker(char *procname) 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 { @@ -678,7 +1285,6 @@ int run_as_create_worker(char *procname) global_worker = worker; } end: - pthread_mutex_unlock(&worker_lock); return ret; /* Error handling. */ @@ -693,20 +1299,20 @@ error_fork: worker->sockpair[i] = -1; } error_sock: + free(worker->procname); +error_procname_alloc: free(worker); - pthread_mutex_unlock(&worker_lock); return ret; } -LTTNG_HIDDEN -void run_as_destroy_worker(void) +static +void run_as_destroy_worker_no_lock(void) { struct run_as_worker *worker = global_worker; DBG("Destroying run_as worker"); - pthread_mutex_lock(&worker_lock); if (!worker) { - goto end; + return; } /* Close unix socket */ DBG("Closing run_as worker socket"); @@ -731,7 +1337,7 @@ void run_as_destroy_worker(void) if (WIFEXITED(status)) { LOG(WEXITSTATUS(status) == 0 ? PRINT_DBG : PRINT_ERR, DEFAULT_RUN_AS_WORKER_NAME " terminated with status code %d", - WEXITSTATUS(status)); + WEXITSTATUS(status)); break; } else if (WIFSIGNALED(status)) { ERR(DEFAULT_RUN_AS_WORKER_NAME " was killed by signal %d", @@ -739,8 +1345,405 @@ void run_as_destroy_worker(void) break; } } + free(worker->procname); free(worker); global_worker = NULL; -end: +} + +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"); + + 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; +} + +LTTNG_HIDDEN +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); +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +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); +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +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); +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +int run_as_unlink(const char *path, uid_t uid, gid_t gid) +{ + return run_as_unlinkat(AT_FDCWD, path, uid, gid); +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +int run_as_rmdir(const char *path, uid_t uid, gid_t gid) +{ + return run_as_rmdirat(AT_FDCWD, path, uid, gid); +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +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); +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +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); +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +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; +} + +LTTNG_HIDDEN +void run_as_destroy_worker(void) +{ + pthread_mutex_lock(&worker_lock); + run_as_destroy_worker_no_lock(); pthread_mutex_unlock(&worker_lock); }