/* * Copyright (c) 1999-2005, 2008-2013 Todd C. Miller * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * * Sponsored in part by the Defense Advanced Research Projects * Agency (DARPA) and Air Force Research Laboratory, Air Force * Materiel Command, USAF, under agreement number F39502-99-1-0512. */ #include #include #include #ifdef STDC_HEADERS # include # include #else # ifdef HAVE_STDLIB_H # include # endif #endif /* STDC_HEADERS */ #ifdef HAVE_STRING_H # include #endif /* HAVE_STRING_H */ #ifdef HAVE_STRINGS_H # include #endif /* HAVE_STRINGS_H */ #ifdef HAVE_UNISTD_H # include #endif /* HAVE_UNISTD_H */ #include #include #include #include "sudoers.h" #include "sudo_auth.h" #include "insults.h" static sudo_auth auth_switch[] = { /* Standalone entries first */ #ifdef HAVE_PAM AUTH_ENTRY("pam", FLAG_STANDALONE, sudo_pam_init, NULL, sudo_pam_verify, sudo_pam_cleanup, sudo_pam_begin_session, sudo_pam_end_session) #endif #ifdef HAVE_SECURID AUTH_ENTRY("SecurId", FLAG_STANDALONE, sudo_securid_init, sudo_securid_setup, sudo_securid_verify, NULL, NULL, NULL) #endif #ifdef HAVE_SIA_SES_INIT AUTH_ENTRY("sia", FLAG_STANDALONE, NULL, sudo_sia_setup, sudo_sia_verify, sudo_sia_cleanup, NULL, NULL) #endif #ifdef HAVE_AIXAUTH AUTH_ENTRY("aixauth", FLAG_STANDALONE, NULL, NULL, sudo_aix_verify, sudo_aix_cleanup, NULL, NULL) #endif #ifdef HAVE_FWTK AUTH_ENTRY("fwtk", FLAG_STANDALONE, sudo_fwtk_init, NULL, sudo_fwtk_verify, sudo_fwtk_cleanup, NULL, NULL) #endif #ifdef HAVE_BSD_AUTH_H AUTH_ENTRY("bsdauth", FLAG_STANDALONE, bsdauth_init, NULL, bsdauth_verify, bsdauth_cleanup, NULL, NULL) #endif /* Non-standalone entries */ #ifndef WITHOUT_PASSWD AUTH_ENTRY("passwd", 0, sudo_passwd_init, NULL, sudo_passwd_verify, sudo_passwd_cleanup, NULL, NULL) #endif #if defined(HAVE_GETPRPWNAM) && !defined(WITHOUT_PASSWD) AUTH_ENTRY("secureware", 0, sudo_secureware_init, NULL, sudo_secureware_verify, sudo_secureware_cleanup, NULL, NULL) #endif #ifdef HAVE_AFS AUTH_ENTRY("afs", 0, NULL, NULL, sudo_afs_verify, NULL, NULL, NULL) #endif #ifdef HAVE_DCE AUTH_ENTRY("dce", 0, NULL, NULL, sudo_dce_verify, NULL, NULL, NULL) #endif #ifdef HAVE_KERB5 AUTH_ENTRY("kerb5", 0, sudo_krb5_init, sudo_krb5_setup, sudo_krb5_verify, sudo_krb5_cleanup, NULL, NULL) #endif #ifdef HAVE_SKEY AUTH_ENTRY("S/Key", 0, NULL, sudo_rfc1938_setup, sudo_rfc1938_verify, NULL, NULL, NULL) #endif #ifdef HAVE_OPIE AUTH_ENTRY("OPIE", 0, NULL, sudo_rfc1938_setup, sudo_rfc1938_verify, NULL, NULL, NULL) #endif AUTH_ENTRY(NULL, 0, NULL, NULL, NULL, NULL, NULL, NULL) }; static int standalone; extern char **NewArgv; /* XXX - for auditing */ static void pass_warn(void); /* * Initialize sudoers authentication method(s). * Returns 0 on success and -1 on error. */ int sudo_auth_init(struct passwd *pw) { sudo_auth *auth; int status = AUTH_SUCCESS; debug_decl(sudo_auth_init, SUDO_DEBUG_AUTH) if (auth_switch[0].name == NULL) debug_return_int(0); /* Make sure we haven't mixed standalone and shared auth methods. */ standalone = IS_STANDALONE(&auth_switch[0]); if (standalone && auth_switch[1].name != NULL) { audit_failure(NewArgv, N_("invalid authentication methods")); log_fatal(0, N_("Invalid authentication methods compiled into sudo! " "You may not mix standalone and non-standalone authentication.")); debug_return_int(-1); } /* Set FLAG_ONEANDONLY if there is only one auth method. */ if (auth_switch[1].name == NULL) SET(auth_switch[0].flags, FLAG_ONEANDONLY); /* Initialize auth methods and unconfigure the method if necessary. */ for (auth = auth_switch; auth->name; auth++) { if (auth->init && !IS_DISABLED(auth)) { if (NEEDS_USER(auth)) set_perms(PERM_USER); status = (auth->init)(pw, auth); if (NEEDS_USER(auth)) restore_perms(); /* Disable if it failed to init unless there was a fatal error. */ if (status == AUTH_FAILURE) SET(auth->flags, FLAG_DISABLED); else if (status == AUTH_FATAL) break; /* assume error msg already printed */ } } debug_return_int(status == AUTH_FATAL ? -1 : 0); } /* * Cleanup all authentication methods. * Returns 0 on success and -1 on error. */ int sudo_auth_cleanup(struct passwd *pw) { sudo_auth *auth; int status = AUTH_SUCCESS; debug_decl(sudo_auth_cleanup, SUDO_DEBUG_AUTH) /* Call cleanup routines. */ for (auth = auth_switch; auth->name; auth++) { if (auth->cleanup && !IS_DISABLED(auth)) { if (NEEDS_USER(auth)) set_perms(PERM_USER); status = (auth->cleanup)(pw, auth); if (NEEDS_USER(auth)) restore_perms(); if (status == AUTH_FATAL) break; /* assume error msg already printed */ } } debug_return_int(status == AUTH_FATAL ? -1 : 0); } /* * Verify the specified user. * Returns true if verified, false if not or -1 on error. */ int verify_user(struct passwd *pw, char *prompt, int validated) { unsigned int counter = def_passwd_tries + 1; int success = AUTH_FAILURE; int status, rval; char *p; sudo_auth *auth; sigaction_t sa, osa; debug_decl(verify_user, SUDO_DEBUG_AUTH) /* Enable suspend during password entry. */ sigemptyset(&sa.sa_mask); sa.sa_flags = SA_RESTART; sa.sa_handler = SIG_DFL; (void) sigaction(SIGTSTP, &sa, &osa); /* Make sure we have at least one auth method. */ /* XXX - check FLAG_DISABLED too */ if (auth_switch[0].name == NULL) { audit_failure(NewArgv, N_("no authentication methods")); log_warning(0, N_("There are no authentication methods compiled into sudo! " "If you want to turn off authentication, use the " "--disable-authentication configure option.")); debug_return_int(-1); } while (--counter) { /* Do any per-method setup and unconfigure the method if needed */ for (auth = auth_switch; auth->name; auth++) { if (auth->setup && !IS_DISABLED(auth)) { if (NEEDS_USER(auth)) set_perms(PERM_USER); status = (auth->setup)(pw, &prompt, auth); if (NEEDS_USER(auth)) restore_perms(); if (status == AUTH_FAILURE) SET(auth->flags, FLAG_DISABLED); else if (status == AUTH_FATAL) goto done; /* assume error msg already printed */ } } /* Get the password unless the auth function will do it for us */ if (standalone) { p = prompt; } else { p = auth_getpass(prompt, def_passwd_timeout * 60, SUDO_CONV_PROMPT_ECHO_OFF); if (p == NULL) break; } /* Call authentication functions. */ for (auth = auth_switch; auth->name; auth++) { if (IS_DISABLED(auth)) continue; if (NEEDS_USER(auth)) set_perms(PERM_USER); success = auth->status = (auth->verify)(pw, p, auth); if (NEEDS_USER(auth)) restore_perms(); if (auth->status != AUTH_FAILURE) goto done; } if (!standalone) memset_s(p, SUDO_CONV_REPL_MAX, 0, strlen(p)); pass_warn(); } done: switch (success) { case AUTH_SUCCESS: (void) sigaction(SIGTSTP, &osa, NULL); rval = true; break; case AUTH_INTR: case AUTH_FAILURE: if (counter != def_passwd_tries) validated |= FLAG_BAD_PASSWORD; log_auth_failure(validated, def_passwd_tries - counter); rval = false; break; case AUTH_FATAL: default: log_auth_failure(validated | FLAG_AUTH_ERROR, 0); rval = -1; break; } debug_return_int(rval); } /* * Call authentication method begin session hooks. * Returns 1 on success and -1 on error. */ int sudo_auth_begin_session(struct passwd *pw, char **user_env[]) { sudo_auth *auth; int status = AUTH_SUCCESS; debug_decl(sudo_auth_begin_session, SUDO_DEBUG_AUTH) for (auth = auth_switch; auth->name; auth++) { if (auth->begin_session && !IS_DISABLED(auth)) { status = (auth->begin_session)(pw, user_env, auth); if (status == AUTH_FATAL) break; /* assume error msg already printed */ } } debug_return_int(status == AUTH_FATAL ? -1 : 1); } bool sudo_auth_needs_end_session(void) { sudo_auth *auth; bool needed = false; debug_decl(sudo_auth_needs_end_session, SUDO_DEBUG_AUTH) for (auth = auth_switch; auth->name; auth++) { if (auth->end_session && !IS_DISABLED(auth)) { needed = true; break; } } debug_return_bool(needed); } /* * Call authentication method end session hooks. * Returns 1 on success and -1 on error. */ int sudo_auth_end_session(struct passwd *pw) { sudo_auth *auth; int status = AUTH_SUCCESS; debug_decl(sudo_auth_end_session, SUDO_DEBUG_AUTH) for (auth = auth_switch; auth->name; auth++) { if (auth->end_session && !IS_DISABLED(auth)) { status = (auth->end_session)(pw, auth); if (status == AUTH_FATAL) break; /* assume error msg already printed */ } } debug_return_int(status == AUTH_FATAL ? -1 : 1); } static void pass_warn(void) { const char *warning = def_badpass_message; debug_decl(pass_warn, SUDO_DEBUG_AUTH) #ifdef INSULT if (def_insults) warning = INSULT; #endif sudo_printf(SUDO_CONV_ERROR_MSG, "%s\n", warning); debug_return; } char * auth_getpass(const char *prompt, int timeout, int type) { struct sudo_conv_message msg; struct sudo_conv_reply repl; debug_decl(auth_getpass, SUDO_DEBUG_AUTH) /* Mask user input if pwfeedback set and echo is off. */ if (type == SUDO_CONV_PROMPT_ECHO_OFF && def_pwfeedback) type = SUDO_CONV_PROMPT_MASK; /* If visiblepw set, do not error out if there is no tty. */ if (def_visiblepw) type |= SUDO_CONV_PROMPT_ECHO_OK; /* Call conversation function */ memset(&msg, 0, sizeof(msg)); msg.msg_type = type; msg.timeout = def_passwd_timeout * 60; msg.msg = prompt; memset(&repl, 0, sizeof(repl)); sudo_conv(1, &msg, &repl); /* XXX - check for ENOTTY? */ debug_return_str_masked(repl.reply); } void dump_auth_methods(void) { sudo_auth *auth; debug_decl(dump_auth_methods, SUDO_DEBUG_AUTH) sudo_printf(SUDO_CONV_INFO_MSG, _("Authentication methods:")); for (auth = auth_switch; auth->name; auth++) sudo_printf(SUDO_CONV_INFO_MSG, " '%s'", auth->name); sudo_printf(SUDO_CONV_INFO_MSG, "\n"); debug_return; }