The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 1 | /* |
| 2 | ** |
| 3 | ** Copyright 2008, The Android Open Source Project |
| 4 | ** |
| 5 | ** Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | ** you may not use this file except in compliance with the License. |
| 7 | ** You may obtain a copy of the License at |
| 8 | ** |
| 9 | ** http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | ** |
| 11 | ** Unless required by applicable law or agreed to in writing, software |
| 12 | ** distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | ** See the License for the specific language governing permissions and |
| 15 | ** limitations under the License. |
| 16 | */ |
| 17 | |
The Android Open Source Project | 26aaac4 | 2009-03-18 17:39:49 -0700 | [diff] [blame] | 18 | #define LOG_TAG "su" |
| 19 | |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 20 | #include <stdio.h> |
| 21 | #include <stdlib.h> |
| 22 | #include <string.h> |
| 23 | #include <sys/types.h> |
| 24 | #include <dirent.h> |
| 25 | #include <errno.h> |
| 26 | |
| 27 | #include <unistd.h> |
| 28 | #include <time.h> |
| 29 | |
| 30 | #include <pwd.h> |
| 31 | |
The Android Open Source Project | 26aaac4 | 2009-03-18 17:39:49 -0700 | [diff] [blame] | 32 | #include <private/android_filesystem_config.h> |
| 33 | |
JP Abgrall | d198c42 | 2013-01-10 17:04:42 -0800 | [diff] [blame] | 34 | |
| 35 | void pwtoid(const char *tok, uid_t *uid, gid_t *gid) |
| 36 | { |
| 37 | struct passwd *pw; |
| 38 | pw = getpwnam(tok); |
| 39 | if (pw) { |
| 40 | if (uid) *uid = pw->pw_uid; |
| 41 | if (gid) *gid = pw->pw_gid; |
| 42 | } else { |
| 43 | uid_t tmpid = atoi(tok); |
| 44 | if (uid) *uid = tmpid; |
| 45 | if (gid) *gid = tmpid; |
| 46 | } |
| 47 | } |
| 48 | |
| 49 | void extract_uidgids(const char *uidgids, uid_t *uid, gid_t *gid, gid_t *gids, |
| 50 | int *gids_count) |
| 51 | { |
| 52 | char *clobberablegids; |
| 53 | char *nexttok; |
| 54 | char *tok; |
| 55 | int gids_found; |
| 56 | |
| 57 | if (!uidgids || !*uidgids) { |
| 58 | *gid = *uid = 0; |
| 59 | *gids_count = 0; |
| 60 | return; |
| 61 | } |
| 62 | clobberablegids = strdup(uidgids); |
| 63 | strcpy(clobberablegids, uidgids); |
| 64 | nexttok = clobberablegids; |
| 65 | tok = strsep(&nexttok, ","); |
| 66 | pwtoid(tok, uid, gid); |
| 67 | tok = strsep(&nexttok, ","); |
| 68 | if (!tok) { |
| 69 | /* gid is already set above */ |
| 70 | *gids_count = 0; |
| 71 | free(clobberablegids); |
| 72 | return; |
| 73 | } |
| 74 | pwtoid(tok, NULL, gid); |
| 75 | gids_found = 0; |
| 76 | while ((gids_found < *gids_count) && (tok = strsep(&nexttok, ","))) { |
| 77 | pwtoid(tok, NULL, gids); |
| 78 | gids_found++; |
| 79 | gids++; |
| 80 | } |
| 81 | if (nexttok && gids_found == *gids_count) { |
| 82 | fprintf(stderr, "too many group ids\n"); |
| 83 | } |
| 84 | *gids_count = gids_found; |
| 85 | free(clobberablegids); |
| 86 | } |
| 87 | |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 88 | /* |
| 89 | * SU can be given a specific command to exec. UID _must_ be |
| 90 | * specified for this (ie argc => 3). |
| 91 | * |
| 92 | * Usage: |
JP Abgrall | d198c42 | 2013-01-10 17:04:42 -0800 | [diff] [blame] | 93 | * su 1000 |
| 94 | * su 1000 ls -l |
| 95 | * or |
| 96 | * su [uid[,gid[,group1]...] [cmd]] |
| 97 | * E.g. |
| 98 | * su 1000,shell,net_bw_acct,net_bw_stats id |
| 99 | * will return |
| 100 | * uid=1000(system) gid=2000(shell) groups=3006(net_bw_stats),3007(net_bw_acct) |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 101 | */ |
| 102 | int main(int argc, char **argv) |
| 103 | { |
| 104 | struct passwd *pw; |
JP Abgrall | d198c42 | 2013-01-10 17:04:42 -0800 | [diff] [blame] | 105 | uid_t uid, myuid; |
| 106 | gid_t gid, gids[10]; |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 107 | |
Nick Kralevich | 17928c8 | 2012-04-02 13:29:35 -0700 | [diff] [blame] | 108 | /* Until we have something better, only root and the shell can use su. */ |
| 109 | myuid = getuid(); |
| 110 | if (myuid != AID_ROOT && myuid != AID_SHELL) { |
| 111 | fprintf(stderr,"su: uid %d not allowed to su\n", myuid); |
| 112 | return 1; |
| 113 | } |
| 114 | |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 115 | if(argc < 2) { |
| 116 | uid = gid = 0; |
| 117 | } else { |
JP Abgrall | d198c42 | 2013-01-10 17:04:42 -0800 | [diff] [blame] | 118 | int gids_count = sizeof(gids)/sizeof(gids[0]); |
| 119 | extract_uidgids(argv[1], &uid, &gid, gids, &gids_count); |
| 120 | if(gids_count) { |
| 121 | if(setgroups(gids_count, gids)) { |
| 122 | fprintf(stderr, "su: failed to set groups\n"); |
| 123 | return 1; |
| 124 | } |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 125 | } |
| 126 | } |
| 127 | |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 128 | if(setgid(gid) || setuid(uid)) { |
| 129 | fprintf(stderr,"su: permission denied\n"); |
| 130 | return 1; |
| 131 | } |
| 132 | |
| 133 | /* User specified command for exec. */ |
| 134 | if (argc == 3 ) { |
| 135 | if (execlp(argv[2], argv[2], NULL) < 0) { |
JP Abgrall | d198c42 | 2013-01-10 17:04:42 -0800 | [diff] [blame] | 136 | int saved_errno = errno; |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 137 | fprintf(stderr, "su: exec failed for %s Error:%s\n", argv[2], |
| 138 | strerror(errno)); |
JP Abgrall | d198c42 | 2013-01-10 17:04:42 -0800 | [diff] [blame] | 139 | return -saved_errno; |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 140 | } |
| 141 | } else if (argc > 3) { |
| 142 | /* Copy the rest of the args from main. */ |
| 143 | char *exec_args[argc - 1]; |
| 144 | memset(exec_args, 0, sizeof(exec_args)); |
| 145 | memcpy(exec_args, &argv[2], sizeof(exec_args)); |
| 146 | if (execvp(argv[2], exec_args) < 0) { |
JP Abgrall | d198c42 | 2013-01-10 17:04:42 -0800 | [diff] [blame] | 147 | int saved_errno = errno; |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 148 | fprintf(stderr, "su: exec failed for %s Error:%s\n", argv[2], |
| 149 | strerror(errno)); |
JP Abgrall | d198c42 | 2013-01-10 17:04:42 -0800 | [diff] [blame] | 150 | return -saved_errno; |
The Android Open Source Project | e16cb84 | 2009-03-03 19:32:58 -0800 | [diff] [blame] | 151 | } |
| 152 | } |
| 153 | |
| 154 | /* Default exec shell. */ |
| 155 | execlp("/system/bin/sh", "sh", NULL); |
| 156 | |
| 157 | fprintf(stderr, "su: exec failed\n"); |
| 158 | return 1; |
| 159 | } |