1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CHROME_BROWSER_COCOA_AUTHORIZATION_UTIL_H_ 6 #define CHROME_BROWSER_COCOA_AUTHORIZATION_UTIL_H_ 7 #pragma once 8 9 // AuthorizationExecuteWithPrivileges fork()s and exec()s the tool, but it 10 // does not wait() for it. It also doesn't provide the caller with access to 11 // the forked pid. If used irresponsibly, zombie processes will accumulate. 12 // 13 // Apple's really gotten us between a rock and a hard place, here. 14 // 15 // Fortunately, AuthorizationExecuteWithPrivileges does give access to the 16 // tool's stdout (and stdin) via a FILE* pipe. The tool can output its pid 17 // to this pipe, and the main program can read it, and then have something 18 // that it can wait() for. 19 // 20 // The contract is that any tool executed by the wrappers declared in this 21 // file must print its pid to stdout on a line by itself before doing anything 22 // else. 23 // 24 // http://developer.apple.com/library/mac/#samplecode/BetterAuthorizationSample/Listings/BetterAuthorizationSampleLib_c.html 25 // (Look for "What's This About Zombies?") 26 27 #include <CoreFoundation/CoreFoundation.h> 28 #include <Security/Authorization.h> 29 #include <stdio.h> 30 #include <sys/types.h> 31 32 namespace authorization_util { 33 34 // Obtains an AuthorizationRef that can be used to run commands as root. If 35 // necessary, prompts the user for authentication. If the user is prompted, 36 // |prompt| will be used as the prompt string and an icon appropriate for the 37 // application will be displayed in a prompt dialog. Note that the system 38 // appends its own text to the prompt string. Returns NULL on failure. 39 AuthorizationRef AuthorizationCreateToRunAsRoot(CFStringRef prompt); 40 41 // Calls straight through to AuthorizationExecuteWithPrivileges. If that 42 // call succeeds, |pid| will be set to the pid of the executed tool. If the 43 // pid can't be determined, |pid| will be set to -1. |pid| must not be NULL. 44 // |pipe| may be NULL, but the tool will always be executed with a pipe in 45 // order to read the pid from its stdout. 46 OSStatus ExecuteWithPrivilegesAndGetPID(AuthorizationRef authorization, 47 const char* tool_path, 48 AuthorizationFlags options, 49 const char** arguments, 50 FILE** pipe, 51 pid_t* pid); 52 53 // Calls ExecuteWithPrivilegesAndGetPID, and if that call succeeds, calls 54 // waitpid() to wait for the process to exit. If waitpid() succeeds, the 55 // exit status is placed in |exit_status|, otherwise, -1 is stored. 56 // |exit_status| may be NULL and this function will still wait for the process 57 // to exit. 58 OSStatus ExecuteWithPrivilegesAndWait(AuthorizationRef authorization, 59 const char* tool_path, 60 AuthorizationFlags options, 61 const char** arguments, 62 FILE** pipe, 63 int* exit_status); 64 65 } // namespace authorization_util 66 67 #endif // CHROME_BROWSER_COCOA_AUTHORIZATION_UTIL_H_ 68