1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Helper functions for handling target threads/cpus 4 * 5 * Copyright (C) 2012, LG Electronics, Namhyung Kim <namhyung.kim@lge.com> 6 */ 7 8 #include "target.h" 9 10 #include <pwd.h> 11 #include <stdio.h> 12 #include <stdlib.h> 13 #include <string.h> 14 #include <linux/kernel.h> 15 #include <linux/string.h> 16 17 enum target_errno target__validate(struct target *target) 18 { 19 enum target_errno ret = TARGET_ERRNO__SUCCESS; 20 21 if (target->pid) 22 target->tid = target->pid; 23 24 /* CPU and PID are mutually exclusive */ 25 if (target->tid && target->cpu_list) { 26 target->cpu_list = NULL; 27 if (ret == TARGET_ERRNO__SUCCESS) 28 ret = TARGET_ERRNO__PID_OVERRIDE_CPU; 29 } 30 31 /* UID and PID are mutually exclusive */ 32 if (target->tid && target->uid_str) { 33 target->uid_str = NULL; 34 if (ret == TARGET_ERRNO__SUCCESS) 35 ret = TARGET_ERRNO__PID_OVERRIDE_UID; 36 } 37 38 /* UID and CPU are mutually exclusive */ 39 if (target->uid_str && target->cpu_list) { 40 target->cpu_list = NULL; 41 if (ret == TARGET_ERRNO__SUCCESS) 42 ret = TARGET_ERRNO__UID_OVERRIDE_CPU; 43 } 44 45 /* PID and SYSTEM are mutually exclusive */ 46 if (target->tid && target->system_wide) { 47 target->system_wide = false; 48 if (ret == TARGET_ERRNO__SUCCESS) 49 ret = TARGET_ERRNO__PID_OVERRIDE_SYSTEM; 50 } 51 52 /* UID and SYSTEM are mutually exclusive */ 53 if (target->uid_str && target->system_wide) { 54 target->system_wide = false; 55 if (ret == TARGET_ERRNO__SUCCESS) 56 ret = TARGET_ERRNO__UID_OVERRIDE_SYSTEM; 57 } 58 59 /* THREAD and SYSTEM/CPU are mutually exclusive */ 60 if (target->per_thread && (target->system_wide || target->cpu_list)) { 61 target->per_thread = false; 62 if (ret == TARGET_ERRNO__SUCCESS) 63 ret = TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD; 64 } 65 66 return ret; 67 } 68 69 enum target_errno target__parse_uid(struct target *target) 70 { 71 struct passwd pwd, *result; 72 char buf[1024]; 73 const char *str = target->uid_str; 74 75 target->uid = UINT_MAX; 76 if (str == NULL) 77 return TARGET_ERRNO__SUCCESS; 78 79 /* Try user name first */ 80 getpwnam_r(str, &pwd, buf, sizeof(buf), &result); 81 82 if (result == NULL) { 83 /* 84 * The user name not found. Maybe it's a UID number. 85 */ 86 char *endptr; 87 int uid = strtol(str, &endptr, 10); 88 89 if (*endptr != '\0') 90 return TARGET_ERRNO__INVALID_UID; 91 92 getpwuid_r(uid, &pwd, buf, sizeof(buf), &result); 93 94 if (result == NULL) 95 return TARGET_ERRNO__USER_NOT_FOUND; 96 } 97 98 target->uid = result->pw_uid; 99 return TARGET_ERRNO__SUCCESS; 100 } 101 102 /* 103 * This must have a same ordering as the enum target_errno. 104 */ 105 static const char *target__error_str[] = { 106 "PID/TID switch overriding CPU", 107 "PID/TID switch overriding UID", 108 "UID switch overriding CPU", 109 "PID/TID switch overriding SYSTEM", 110 "UID switch overriding SYSTEM", 111 "SYSTEM/CPU switch overriding PER-THREAD", 112 "Invalid User: %s", 113 "Problems obtaining information for user %s", 114 }; 115 116 int target__strerror(struct target *target, int errnum, 117 char *buf, size_t buflen) 118 { 119 int idx; 120 const char *msg; 121 122 BUG_ON(buflen == 0); 123 124 if (errnum >= 0) { 125 str_error_r(errnum, buf, buflen); 126 return 0; 127 } 128 129 if (errnum < __TARGET_ERRNO__START || errnum >= __TARGET_ERRNO__END) 130 return -1; 131 132 idx = errnum - __TARGET_ERRNO__START; 133 msg = target__error_str[idx]; 134 135 switch (errnum) { 136 case TARGET_ERRNO__PID_OVERRIDE_CPU ... 137 TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD: 138 snprintf(buf, buflen, "%s", msg); 139 break; 140 141 case TARGET_ERRNO__INVALID_UID: 142 case TARGET_ERRNO__USER_NOT_FOUND: 143 snprintf(buf, buflen, msg, target->uid_str); 144 break; 145 146 default: 147 /* cannot reach here */ 148 break; 149 } 150 151 return 0; 152 } 153