1/* 2 * Copyright (c) 2002, 2008, 2009 Apple Inc. All rights reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * The contents of this file constitute Original Code as defined in and 7 * are subject to the Apple Public Source License Version 1.1 (the 8 * "License"). You may not use this file except in compliance with the 9 * License. Please obtain a copy of the License at 10 * http://www.apple.com/publicsource and read it before using this file. 11 * 12 * This Original Code and all software distributed under the License are 13 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER 14 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 15 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the 17 * License for the specific language governing rights and limitations 18 * under the License. 19 * 20 * @APPLE_LICENSE_HEADER_END@ 21 */ 22 23#include <stdbool.h> 24#include <stdlib.h> 25#include <ctype.h> 26#include <signal.h> 27#include <string.h> 28#include <curses.h> 29#include <errno.h> 30#include "preferences.h" 31#include "userinput.h" 32 33static bool is_empty(const char *s) { 34 35 while(*s) { 36 if(!isspace(*s)) { 37 return false; 38 } 39 40 ++s; 41 } 42 43 return true; 44} 45 46static bool is_pid(const char *s) { 47 const char *sp; 48 49 for(sp = s; *sp; ++sp) { 50 if(!isdigit(*sp)) { 51 return false; 52 } 53 } 54 55 /* If the string was not an empty string, then it contains digits. */ 56 if(sp != s) { 57 return true; 58 } 59 60 return false; 61} 62 63static void reset_pid(struct user_input_state *s) { 64 s->buf[0] = '\0'; 65 s->offset = 0; 66} 67 68static void signal_pid_completion(void *tinst, struct user_input_state *s) { 69 const char *signame; 70 int sig; 71 int err; 72 uid_t euid; 73 gid_t egid; 74 int saved_errno = 0; 75 pid_t pid; 76 77 if(is_empty(s->buf)) { 78 /* 79 * Any empty buffer indicates that the user didn't want 80 * to signal the process after all. 81 */ 82 83 reset_pid(s); 84 user_input_set_state(NULL); 85 return; 86 } 87 88 if(!is_pid(s->buf)) { 89 reset_pid(s); 90 user_input_set_error_state("invalid pid"); 91 return; 92 } 93 94 pid = atoi(s->buf); 95 96 reset_pid(s); 97 98 sig = top_prefs_get_signal(&signame); 99 100 /* Temporarily drop permissions. */ 101 euid = geteuid(); 102 egid = getegid(); 103 104 if(-1 == seteuid(getuid()) 105 || -1 == setegid(getgid())) { 106 user_input_set_error_state("missing setuid bit"); 107 return; 108 } 109 110 err = kill(pid, sig); 111 112 if(-1 == err) 113 saved_errno = errno; 114 115 if(-1 == seteuid(euid) 116 || -1 == setegid(egid)) { 117 user_input_set_error_state("restoring setuid bit"); 118 return; 119 } 120 121 switch(saved_errno) { 122 case EINVAL: 123 user_input_set_error_state("invalid signal"); 124 return; 125 126 case ESRCH: 127 user_input_set_error_state("invalid pid"); 128 return; 129 130 case EPERM: 131 user_input_set_error_state("permission error signaling"); 132 return; 133 } 134 135 user_input_set_state(NULL); 136} 137 138static void signal_pid_draw(void *tinst, struct user_input_state *s, 139 WINDOW *win, int row, int column) { 140 char display[60]; 141 142 if(-1 == snprintf(display, sizeof(display), "pid: %s", s->buf)) { 143 user_input_set_error_state("string input too long!"); 144 return; 145 } 146 147 mvwaddstr(win, row, column, display); 148} 149 150struct user_input_state top_user_input_signal_pid_state = { 151 .offset = 0, 152 .completion = signal_pid_completion, 153 .draw = signal_pid_draw 154}; 155 156static void signal_completion(void *tinst, struct user_input_state *s) { 157 158 if(!strlen(s->buf)) { 159 /* Use the current default. */ 160 user_input_set_state(&top_user_input_signal_pid_state); 161 return; 162 } 163 164 if(top_prefs_set_signal_string(s->buf)) { 165 user_input_set_error_state("invalid signal name"); 166 return; 167 } 168 169 user_input_set_state(&top_user_input_signal_pid_state); 170} 171 172static void signal_draw(void *tinst, struct user_input_state *s, WINDOW *win, 173 int row, int column) { 174 char display[60]; 175 const char *signame; 176 177 (void)top_prefs_get_signal(&signame); 178 179 if(-1 == snprintf(display, sizeof(display), "signal [%s]: %s", 180 signame, s->buf)) { 181 user_input_set_error_state("string input too long!"); 182 return; 183 } 184 185 mvwaddstr(win, row, column, display); 186} 187 188struct user_input_state top_user_input_signal_state = { 189 .offset = 0, 190 .completion = signal_completion, 191 .draw = signal_draw 192}; 193