| 1 | /* |
| 2 | * Babeltrace common functions |
| 3 | * |
| 4 | * Copyright 2016 Philippe Proulx <pproulx@efficios.com> |
| 5 | * |
| 6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 7 | * of this software and associated documentation files (the "Software"), to deal |
| 8 | * in the Software without restriction, including without limitation the rights |
| 9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 10 | * copies of the Software, and to permit persons to whom the Software is |
| 11 | * furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in |
| 14 | * all copies or substantial portions of the Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 19 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 22 | * SOFTWARE. |
| 23 | */ |
| 24 | |
| 25 | #include <string.h> |
| 26 | #include <sys/types.h> |
| 27 | #include <pwd.h> |
| 28 | #include <unistd.h> |
| 29 | #include <assert.h> |
| 30 | #include <glib.h> |
| 31 | #include <babeltrace/babeltrace-internal.h> |
| 32 | |
| 33 | #define SYSTEM_PLUGIN_PATH INSTALL_LIBDIR "/babeltrace/plugins" |
| 34 | #define HOME_ENV_VAR "HOME" |
| 35 | #define HOME_PLUGIN_SUBPATH "/.local/lib/babeltrace/plugins" |
| 36 | |
| 37 | BT_HIDDEN |
| 38 | const char *bt_common_get_system_plugin_path(void) |
| 39 | { |
| 40 | return SYSTEM_PLUGIN_PATH; |
| 41 | } |
| 42 | |
| 43 | BT_HIDDEN |
| 44 | bool bt_common_is_setuid_setgid(void) |
| 45 | { |
| 46 | return (geteuid() != getuid() || getegid() != getgid()); |
| 47 | } |
| 48 | |
| 49 | static char *bt_secure_getenv(const char *name) |
| 50 | { |
| 51 | if (bt_common_is_setuid_setgid()) { |
| 52 | printf_error("Disregarding %s environment variable for setuid/setgid binary", |
| 53 | name); |
| 54 | return NULL; |
| 55 | } |
| 56 | return getenv(name); |
| 57 | } |
| 58 | |
| 59 | static const char *get_home_dir(void) |
| 60 | { |
| 61 | char *val = NULL; |
| 62 | struct passwd *pwd; |
| 63 | |
| 64 | val = bt_secure_getenv(HOME_ENV_VAR); |
| 65 | if (val) { |
| 66 | goto end; |
| 67 | } |
| 68 | /* Fallback on password file. */ |
| 69 | pwd = getpwuid(getuid()); |
| 70 | if (!pwd) { |
| 71 | goto end; |
| 72 | } |
| 73 | val = pwd->pw_dir; |
| 74 | end: |
| 75 | return val; |
| 76 | } |
| 77 | |
| 78 | BT_HIDDEN |
| 79 | char *bt_common_get_home_plugin_path(void) |
| 80 | { |
| 81 | char *path = NULL; |
| 82 | const char *home_dir; |
| 83 | |
| 84 | home_dir = get_home_dir(); |
| 85 | if (!home_dir) { |
| 86 | goto end; |
| 87 | } |
| 88 | |
| 89 | if (strlen(home_dir) + strlen(HOME_PLUGIN_SUBPATH) + 1 >= PATH_MAX) { |
| 90 | printf_error("Home directory path is too long: `%s`\n", |
| 91 | home_dir); |
| 92 | goto end; |
| 93 | } |
| 94 | |
| 95 | path = malloc(PATH_MAX); |
| 96 | if (!path) { |
| 97 | goto end; |
| 98 | } |
| 99 | |
| 100 | strcpy(path, home_dir); |
| 101 | strcat(path, HOME_PLUGIN_SUBPATH); |
| 102 | |
| 103 | end: |
| 104 | return path; |
| 105 | } |
| 106 | |
| 107 | BT_HIDDEN |
| 108 | int bt_common_append_plugin_path_dirs(const char *paths, GPtrArray *dirs) |
| 109 | { |
| 110 | int ret = 0; |
| 111 | const char *at; |
| 112 | const char *end; |
| 113 | size_t init_dirs_len; |
| 114 | |
| 115 | assert(dirs); |
| 116 | init_dirs_len = dirs->len; |
| 117 | |
| 118 | if (!paths) { |
| 119 | /* Nothing to append */ |
| 120 | goto end; |
| 121 | } |
| 122 | |
| 123 | at = paths; |
| 124 | end = paths + strlen(paths); |
| 125 | |
| 126 | while (at < end) { |
| 127 | GString *path; |
| 128 | const char *next_colon; |
| 129 | |
| 130 | next_colon = strchr(at, ':'); |
| 131 | if (next_colon == at) { |
| 132 | /* |
| 133 | * Empty path: try next character (supported |
| 134 | * to conform to the typical parsing of $PATH). |
| 135 | */ |
| 136 | at++; |
| 137 | continue; |
| 138 | } else if (!next_colon) { |
| 139 | /* No more colon: use the remaining */ |
| 140 | next_colon = paths + strlen(paths); |
| 141 | } |
| 142 | |
| 143 | path = g_string_new(NULL); |
| 144 | if (!path) { |
| 145 | goto error; |
| 146 | } |
| 147 | |
| 148 | g_string_append_len(path, at, next_colon - at); |
| 149 | at = next_colon + 1; |
| 150 | g_ptr_array_add(dirs, path); |
| 151 | } |
| 152 | |
| 153 | goto end; |
| 154 | |
| 155 | error: |
| 156 | ret = -1; |
| 157 | |
| 158 | /* Remove the new entries in dirs */ |
| 159 | while (dirs->len > init_dirs_len) { |
| 160 | g_ptr_array_remove_index(dirs, init_dirs_len); |
| 161 | } |
| 162 | |
| 163 | end: |
| 164 | return ret; |
| 165 | } |