diff options
Diffstat (limited to 'runtime/staprun/cap.c')
| -rw-r--r-- | runtime/staprun/cap.c | 166 |
1 files changed, 0 insertions, 166 deletions
diff --git a/runtime/staprun/cap.c b/runtime/staprun/cap.c deleted file mode 100644 index 6ac6701f..00000000 --- a/runtime/staprun/cap.c +++ /dev/null @@ -1,166 +0,0 @@ -/* -*- linux-c -*- - * - * cap.c - staprun capabilities functions - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - * - * Copyright (C) 2007 Red Hat, Inc. - * - */ - -#include "staprun.h" -#include <sys/prctl.h> - -static int _stp_no_caps = 0; - -/* like perror, but exits */ -#define ferror(msg) { \ - _perr(msg); \ - exit(1); \ - } \ - -/* - * init_cap() sets up the initial capabilities for staprun. Then - * it calls prctl( PR_SET_KEEPCAPS) to arrrange to keep these capabilities - * even when not running as root. Next it resets the real, effective, and - * saved uid and gid back to the normal user. - * - * There are two sets of capabilities we are concerned with; permitted - * and effective. The permitted capabilities are all the capabilities - * that this process is ever permitted to have. They are defined in init_cap() - * and may be permanently removed with drop_cap(). - * - * Effective capabilities are the capabilities from the permitted set - * that are currently enabled. A good practice would be to only enable - * capabilities when necessary and to delete or drop them as soon as possible. - * - * Capabilities we might use include: - * - * CAP_SYS_MODULE - insert and remove kernel modules - * CAP_SYS_ADMIN - misc, including mounting and unmounting - * CAP_SYS_NICE - setpriority() - * CAP_SETUID - allows setuid - * CAP_SETGID - allows setgid - * CAP_CHOWN - allows chown - */ - -void init_cap(void) -{ - cap_t caps = cap_init(); - cap_value_t capv[] = { CAP_SYS_MODULE, CAP_SYS_ADMIN, CAP_SYS_NICE, CAP_SETUID, CAP_SETGID, CAP_DAC_OVERRIDE }; - const int numcaps = sizeof(capv) / sizeof(capv[0]); - uid_t uid = getuid(); - gid_t gid = getgid(); - - cap_clear(caps); - if (caps == NULL) - ferror("cap_init"); - - if (cap_set_flag(caps, CAP_PERMITTED, numcaps, capv, CAP_SET) < 0) - ferror("cap_set_flag"); - - if (cap_set_proc(caps) < 0) { - dbug(1, "Setting capabilities failed. Capabilities disabled.\n"); - _stp_no_caps = 1; - return; - } - - cap_free(caps); - - if (prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0) < 0) - ferror("prctl"); - - if (setresuid(uid, uid, uid) < 0) - ferror("setresuid"); - - if (setresgid(gid, gid, gid) < 0) - ferror("setresgid"); -} - -void print_cap(char *text) -{ - int p; - cap_t caps = cap_get_proc(); - uid_t uid, euid, suid; - gid_t gid, egid, sgid; - - if (caps == NULL) { - perr("cap_get_proc"); - return; - } - - getresuid(&uid, &euid, &suid); - getresgid(&gid, &egid, &sgid); - - printf("***** %s\n", text); - - if ((p = prctl(PR_GET_KEEPCAPS, 0, 0, 0, 0)) < 0) - perr("Couldn't get PR_SET_KEEPCAPS flag value"); - else - printf("KEEPCAPS: %d\n", p); - - printf("uid: %d, euid: %d, suid: %d\ngid: %d. egid: %d, sgid: %d\n", uid, euid, suid, gid, egid, sgid); - printf("Caps: %s\n", cap_to_text(caps, NULL)); - cap_free(caps); - printf("*****\n\n"); -} - -/* drop_cap() permanently removes a capability from the permitted set. There is - * no way to recover the capability after this. You do not need to remove - * it from the effective set before calling this. - */ -void drop_cap(cap_value_t cap) -{ - if (_stp_no_caps == 0) { - cap_t caps = cap_get_proc(); - if (caps == NULL) - ferror("cap_get_proc failed"); - if (cap_set_flag(caps, CAP_PERMITTED, 1, &cap, CAP_CLEAR) < 0) - ferror("Could not clear effective capabilities"); - if (cap_set_proc(caps) < 0) - ferror("Could not apply capability set"); - cap_free(caps); - } -} - -/* add_cap() adds a permitted capability to the effective set. */ -void add_cap(cap_value_t cap) -{ - if (_stp_no_caps == 0) { - cap_t caps = cap_get_proc(); - if (caps == NULL) - ferror("cap_get_proc failed"); - if (cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap, CAP_SET) < 0) - ferror("Could not set effective capabilities"); - if (cap_set_proc(caps) < 0) - ferror("Could not apply capability set"); - cap_free(caps); - } -} - -/* del_cap() deletes a permitted capability from the effective set. */ -void del_cap(cap_value_t cap) -{ - if (_stp_no_caps == 0) { - cap_t caps = cap_get_proc(); - if (caps == NULL) - ferror("cap_get_proc failed"); - if (cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap, CAP_CLEAR) < 0) - ferror("Could not clear effective capabilities"); - if (cap_set_proc(caps) < 0) - ferror("Could not apply capability set"); - cap_free(caps); - } -} |