/* * SPDX-License-Identifier: ISC * * Copyright (c) 2010-2017, 2020-2022 Todd C. Miller * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #ifndef SUDO_EXEC_H #define SUDO_EXEC_H /* * Older systems may not support MSG_WAITALL but it shouldn't really be needed. */ #ifndef MSG_WAITALL # define MSG_WAITALL 0 #endif /* * Linux-specific wait flag used with ptrace(2). */ #ifndef __WALL # define __WALL 0 #endif /* * Some older systems support siginfo but predate SI_USER. */ #ifdef SI_USER # define USER_SIGNALED(_info) ((_info) != NULL && (_info)->si_code == SI_USER) #else # define USER_SIGNALED(_info) ((_info) != NULL && (_info)->si_code <= 0) #endif /* Values for ttymode. */ #define TERM_COOKED 0 #define TERM_RAW 1 struct command_details; struct command_status; struct sudo_event_base; struct stat; /* * Closure passed to I/O event callbacks. */ struct exec_closure { struct command_details *details; struct sudo_event_base *evbase; struct sudo_event *backchannel_event; struct sudo_event *fwdchannel_event; struct sudo_event *sigint_event; struct sudo_event *sigquit_event; struct sudo_event *sigtstp_event; struct sudo_event *sigterm_event; struct sudo_event *sighup_event; struct sudo_event *sigalrm_event; struct sudo_event *sigpipe_event; struct sudo_event *sigusr1_event; struct sudo_event *sigusr2_event; struct sudo_event *sigchld_event; struct sudo_event *sigcont_event; struct sudo_event *siginfo_event; struct sudo_event *sigwinch_event; struct command_status *cstat; void *intercept; pid_t sudo_pid; pid_t monitor_pid; pid_t cmnd_pid; pid_t ppgrp; short rows; short cols; }; /* * I/O buffer with associated read/write events and a logging action. * Used to, e.g. pass data from the pty to the user's terminal * and any I/O logging plugins. */ struct io_buffer; typedef bool (*sudo_io_action_t)(const char *, unsigned int, struct io_buffer *); struct io_buffer { SLIST_ENTRY(io_buffer) entries; struct exec_closure *ec; struct sudo_event *revent; struct sudo_event *wevent; sudo_io_action_t action; int len; /* buffer length (how much produced) */ int off; /* write position (how much already consumed) */ char buf[64 * 1024]; }; SLIST_HEAD(io_buffer_list, io_buffer); /* * Indices into io_fds[] when logging I/O. */ #define SFD_STDIN 0 #define SFD_STDOUT 1 #define SFD_STDERR 2 #define SFD_LEADER 3 #define SFD_FOLLOWER 4 #define SFD_USERTTY 5 /* Evaluates to true if the event has /dev/tty as its fd. */ #define USERTTY_EVENT(_ev) (sudo_ev_get_fd((_ev)) == io_fds[SFD_USERTTY]) /* * Special values to indicate whether continuing in foreground or background. */ #define SIGCONT_FG -2 #define SIGCONT_BG -3 /* * Positions in saved_signals[] */ #define SAVED_SIGALRM 0 #define SAVED_SIGCHLD 1 #define SAVED_SIGCONT 2 #define SAVED_SIGHUP 3 #define SAVED_SIGINT 4 #define SAVED_SIGPIPE 5 #define SAVED_SIGQUIT 6 #define SAVED_SIGTERM 7 #define SAVED_SIGTSTP 8 #define SAVED_SIGTTIN 9 #define SAVED_SIGTTOU 10 #define SAVED_SIGUSR1 11 #define SAVED_SIGUSR2 12 /* * Error codes for sesh */ #define SESH_SUCCESS 0 /* successful operation */ #define SESH_ERR_FAILURE 1 /* unspecified error */ #define SESH_ERR_KILLED 2 /* killed by a signal */ #define SESH_ERR_INVALID 30 /* invalid -e arg value */ #define SESH_ERR_BAD_PATHS 31 /* odd number of paths */ #define SESH_ERR_NO_FILES 32 /* copy error, no files copied */ #define SESH_ERR_SOME_FILES 33 /* copy error, some files copied */ #define INTERCEPT_FD_MIN 64 /* minimum fd so shell won't close it */ #define MESSAGE_SIZE_MAX 2097152 /* 2Mib max intercept message size */ union sudo_token_un { unsigned char u8[16]; unsigned int u32[4]; unsigned long long u64[2]; }; #define sudo_token_isset(_t) ((_t).u64[0] || (_t).u64[1]) /* * Use ptrace-based intercept (using seccomp) on Linux if possible. * On MIPS we can't change the syscall return and only support log_subcmds. */ #if defined(_PATH_SUDO_INTERCEPT) && defined(__linux__) # if defined(HAVE_DECL_SECCOMP_MODE_FILTER) && HAVE_DECL_SECCOMP_MODE_FILTER # if defined(__x86_64__) || defined(__i386__) || defined(__aarch64__) || defined(__arm__) || defined(__mips__) || defined(__powerpc__) || (defined(__riscv) && __riscv_xlen == 64) || defined(__s390__) # ifndef HAVE_PTRACE_INTERCEPT # define HAVE_PTRACE_INTERCEPT 1 # endif /* HAVE_PTRACE_INTERCEPT */ # endif /* __amd64__ || __i386__ || __aarch64__ || __riscv || __s390__ */ # endif /* HAVE_DECL_SECCOMP_MODE_FILTER */ #endif /* _PATH_SUDO_INTERCEPT && __linux__ */ /* exec.c */ void exec_cmnd(struct command_details *details, sigset_t *mask, int intercept_fd, int errfd); void terminate_command(pid_t pid, bool use_pgrp); bool sudo_terminated(struct command_status *cstat); void free_exec_closure(struct exec_closure *ec); /* exec_common.c */ int sudo_execve(int fd, const char *path, char *const argv[], char *envp[], int intercept_fd, int flags); char **disable_execute(char *envp[], const char *dso); char **enable_monitor(char *envp[], const char *dso); /* exec_intercept.c */ void *intercept_setup(int fd, struct sudo_event_base *evbase, struct command_details *details); void intercept_cleanup(void); /* exec_iolog.c */ bool log_ttyin(const char *buf, unsigned int n, struct io_buffer *iob); bool log_stdin(const char *buf, unsigned int n, struct io_buffer *iob); bool log_ttyout(const char *buf, unsigned int n, struct io_buffer *iob); bool log_stdout(const char *buf, unsigned int n, struct io_buffer *iob); bool log_stderr(const char *buf, unsigned int n, struct io_buffer *iob); void log_suspend(struct exec_closure *ec, int signo); void log_winchange(struct exec_closure *ec, unsigned int rows, unsigned int cols); void io_buf_new(int rfd, int wfd, bool (*action)(const char *, unsigned int, struct io_buffer *), void (*read_cb)(int fd, int what, void *v), void (*write_cb)(int fd, int what, void *v), struct exec_closure *ec, struct io_buffer_list *head); int safe_close(int fd); void ev_free_by_fd(struct sudo_event_base *evbase, int fd); void free_io_bufs(void); void add_io_events(struct sudo_event_base *evbase); void del_io_events(bool nonblocking); void init_ttyblock(void); extern struct io_buffer_list iobufs; extern int ttymode; /* exec_nopty.c */ void exec_nopty(struct command_details *details, struct command_status *cstat); /* exec_pty.c */ bool exec_pty(struct command_details *details, struct command_status *cstat); void pty_cleanup(void); int pty_make_controlling(void); extern int io_fds[6]; /* exec_monitor.c */ int exec_monitor(struct command_details *details, sigset_t *omask, bool foreground, int backchannel, int intercept_fd); /* utmp.c */ bool utmp_login(const char *from_line, const char *to_line, int ttyfd, const char *user); bool utmp_logout(const char *line, int status); /* exec_preload.c */ char **sudo_preload_dso(char *const envp[], const char *dso_file, int intercept_fd); char **sudo_preload_dso_mmap(char *const envp[], const char *dso_file, int intercept_fd); /* exec_ptrace.c */ bool exec_ptrace_stopped(pid_t pid, int status, void *intercept); bool set_exec_filter(void); int exec_ptrace_seize(pid_t child); /* suspend_nopty.c */ void suspend_sudo_nopty(struct exec_closure *ec, int signo, pid_t my_pid, pid_t my_pgrp, pid_t cmnd_pid); #endif /* SUDO_EXEC_H */