/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License, Version 1.0 only * (the "License"). You may not use this file except in compliance * with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2005 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ /* All Rights Reserved */ /* Copyright (c) 1987, 1988 Microsoft Corporation */ /* All Rights Reserved */ #pragma ident "%Z%%M% %I% %E% SMI" /* * su [-] [name [arg ...]] change userid, `-' changes environment. * If SULOG is defined, all attempts to su to another user are * logged there. * If CONSOLE is defined, all successful attempts to su to uid 0 * are also logged there. * * If su cannot create, open, or write entries into SULOG, * (or on the CONSOLE, if defined), the entry will not * be logged -- thus losing a record of the su's attempted * during this period. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define PATH "/usr/bin:" /* path for users other than root */ #define SUPATH "/usr/sbin:/usr/bin" /* path for root */ #define SUPRMT "PS1=# " /* primary prompt for root */ #define ELIM 128 #define ROOT 0 #ifdef DYNAMIC_SU #define EMBEDDED_NAME "embedded_su" #define DEF_ATTEMPTS 3 /* attempts to change password */ #endif /* DYNAMIC_SU */ #define PW_FALSE 1 /* no password change */ #define PW_TRUE 2 /* successful password change */ #define PW_FAILED 3 /* failed password change */ /* * Intervals to sleep after failed su */ #ifndef SLEEPTIME #define SLEEPTIME 4 #endif #define DEFAULT_LOGIN "/etc/default/login" #define DEFFILE "/etc/default/su" char *Sulog, *Console; char *Path, *Supath; /* * Locale variables to be propagated to "su -" environment */ static char *initvar; static char *initenv[] = { "TZ", "LANG", "LC_CTYPE", "LC_NUMERIC", "LC_TIME", "LC_COLLATE", "LC_MONETARY", "LC_MESSAGES", "LC_ALL", 0}; static char mail[30] = { "MAIL=/var/mail/" }; static void envalt(void); static void log(char *, char *, int); static void to(int); enum messagemode { USAGE, ERR, WARN }; static void message(enum messagemode, char *, ...); static char *alloc_vsprintf(const char *, va_list); static char *tail(char *); static void audit_success(int, struct passwd *); static void audit_failure(int, struct passwd *, int); #ifdef DYNAMIC_SU static void validate(char *, int *); static int legalenvvar(char *); static int su_conv(int, struct pam_message **, struct pam_response **, void *); static int emb_su_conv(int, struct pam_message **, struct pam_response **, void *); static void freeresponse(int, struct pam_response **response); static struct pam_conv pam_conv = {su_conv, NULL}; static struct pam_conv emb_pam_conv = {emb_su_conv, NULL}; static void quotemsg(char *, ...); static void readinitblock(void); #else /* !DYNAMIC_SU */ static void update_audit(struct passwd *pwd); #endif /* DYNAMIC_SU */ static pam_handle_t *pamh = NULL; /* Authentication handle */ struct passwd pwd; char pwdbuf[1024]; /* buffer for getpwnam_r() */ char shell[] = "/usr/bin/sh"; /* default shell */ char safe_shell[] = "/sbin/sh"; /* "fallback" shell */ char su[PATH_MAX] = "su"; /* arg0 for exec of shprog */ char homedir[PATH_MAX] = "HOME="; char logname[20] = "LOGNAME="; char *suprmt = SUPRMT; char termtyp[PATH_MAX] = "TERM="; char *term; char shelltyp[PATH_MAX] = "SHELL="; char *hz; char tznam[PATH_MAX]; char hzname[10] = "HZ="; char path[PATH_MAX] = "PATH="; char supath[PATH_MAX] = "PATH="; char *envinit[ELIM]; extern char **environ; char *ttyn; char *username; /* the invoker */ static int dosyslog = 0; /* use syslog? */ char *myname; #ifdef DYNAMIC_SU int passreq = 0; boolean_t embedded = B_FALSE; #endif /* DYNAMIC_SU */ int main(int argc, char **argv) { #ifndef DYNAMIC_SU struct spwd sp; char spbuf[1024]; /* buffer for getspnam_r() */ char *password; #endif /* !DYNAMIC_SU */ char *nptr; char *pshell; int eflag = 0; int envidx = 0; uid_t uid; gid_t gid; char *dir, *shprog, *name; char *ptr; char *prog = argv[0]; #ifdef DYNAMIC_SU int sleeptime = SLEEPTIME; char **pam_env = 0; int flags = 0; int retcode; int idx = 0; #endif /* DYNAMIC_SU */ int pw_change = PW_FALSE; (void) setlocale(LC_ALL, ""); #if !defined(TEXT_DOMAIN) /* Should be defined by cc -D */ #define TEXT_DOMAIN "SYS_TEST" /* Use this only if it wasn't */ #endif (void) textdomain(TEXT_DOMAIN); myname = tail(argv[0]); #ifdef DYNAMIC_SU if (strcmp(myname, EMBEDDED_NAME) == 0) { embedded = B_TRUE; setbuf(stdin, NULL); setbuf(stdout, NULL); readinitblock(); } #endif /* DYNAMIC_SU */ if (argc > 1 && *argv[1] == '-') { /* Explicitly check for just `-' (no trailing chars) */ if (strlen(argv[1]) == 1) { eflag++; /* set eflag if `-' is specified */ argv++; argc--; } else { message(USAGE, gettext("Usage: %s [-] [ username [ arg ... ] ]"), prog); exit(1); } } /* * Determine specified userid, get their password file entry, * and set variables to values in password file entry fields. */ if (argc > 1) { /* * Usernames can't start with a `-', so we check for that to * catch bad usage (like "su - -c ls"). */ if (*argv[1] == '-') { message(USAGE, gettext("Usage: %s [-] [ username [ arg ... ] ]"), prog); exit(1); } else nptr = argv[1]; /* use valid command-line username */ } else nptr = "root"; /* use default "root" username */ if (defopen(DEFFILE) == 0) { if (Sulog = defread("SULOG=")) Sulog = strdup(Sulog); if (Console = defread("CONSOLE=")) Console = strdup(Console); if (Path = defread("PATH=")) Path = strdup(Path); if (Supath = defread("SUPATH=")) Supath = strdup(Supath); if ((ptr = defread("SYSLOG=")) != NULL) dosyslog = strcmp(ptr, "YES") == 0; (void) defopen(NULL); } (void) strlcat(path, (Path) ? Path : PATH, sizeof (path)); (void) strlcat(supath, (Supath) ? Supath : SUPATH, sizeof (supath)); if ((ttyn = ttyname(0)) == NULL) if ((ttyn = ttyname(1)) == NULL) if ((ttyn = ttyname(2)) == NULL) ttyn = "/dev/???"; if ((username = cuserid(NULL)) == NULL) username = "(null)"; /* * if Sulog defined, create SULOG, if it does not exist, with * mode read/write user. Change owner and group to root */ if (Sulog != NULL) { (void) close(open(Sulog, O_WRONLY | O_APPEND | O_CREAT, (S_IRUSR|S_IWUSR))); (void) chown(Sulog, (uid_t)ROOT, (gid_t)ROOT); } #ifdef DYNAMIC_SU if (pam_start(embedded ? EMBEDDED_NAME : "su", nptr, embedded ? &emb_pam_conv : &pam_conv, &pamh) != PAM_SUCCESS) exit(1); if (pam_set_item(pamh, PAM_TTY, ttyn) != PAM_SUCCESS) exit(1); #endif /* DYNAMIC_SU */ openlog("su", LOG_CONS, LOG_AUTH); #ifdef DYNAMIC_SU /* * Use the same value of sleeptime and password required that * login(1) uses. * This is obtained by reading the file /etc/default/login * using the def*() functions */ if (defopen(DEFAULT_LOGIN) == 0) { if ((ptr = defread("SLEEPTIME=")) != NULL) { sleeptime = atoi(ptr); if (sleeptime < 0 || sleeptime > 5) sleeptime = SLEEPTIME; } if ((ptr = defread("PASSREQ=")) != NULL && strcasecmp("YES", ptr) == 0) passreq = 1; (void) defopen((char *)NULL); } /* * Ignore SIGQUIT and SIGINT */ (void) signal(SIGQUIT, SIG_IGN); (void) signal(SIGINT, SIG_IGN); /* call pam_authenticate() to authenticate the user through PAM */ if (getpwnam_r(nptr, &pwd, pwdbuf, sizeof (pwdbuf)) == NULL) retcode = PAM_USER_UNKNOWN; else if ((flags = (getuid() != (uid_t)ROOT)) != 0) { retcode = pam_authenticate(pamh, 0); } else /* root user does not need to authenticate */ retcode = PAM_SUCCESS; if (retcode != PAM_SUCCESS) { /* * 1st step: audit and log the error. * 2nd step: sleep. * 3rd step: print out message to user. */ audit_failure(PW_FALSE, NULL, retcode); switch (retcode) { case PAM_USER_UNKNOWN: closelog(); (void) sleep(sleeptime); message(ERR, gettext("Unknown id: %s"), nptr); break; case PAM_AUTH_ERR: if (Sulog != NULL) log(Sulog, nptr, 0); /* log entry */ if (dosyslog) syslog(LOG_CRIT, "'su %s' failed for %s on %s", pwd.pw_name, username, ttyn); closelog(); (void) sleep(sleeptime); message(ERR, gettext("Sorry")); break; case PAM_CONV_ERR: default: if (dosyslog) syslog(LOG_CRIT, "'su %s' failed for %s on %s", pwd.pw_name, username, ttyn); closelog(); (void) sleep(sleeptime); message(ERR, gettext("Sorry")); break; } (void) signal(SIGQUIT, SIG_DFL); (void) signal(SIGINT, SIG_DFL); exit(1); } if (flags) validate(username, &pw_change); if (pam_setcred(pamh, PAM_REINITIALIZE_CRED) != PAM_SUCCESS) { message(ERR, gettext("unable to set credentials")); exit(2); } if (dosyslog) syslog(getuid() == 0 ? LOG_INFO : LOG_NOTICE, "'su %s' succeeded for %s on %s", pwd.pw_name, username, ttyn); closelog(); (void) signal(SIGQUIT, SIG_DFL); (void) signal(SIGINT, SIG_DFL); #else /* !DYNAMIC_SU */ if ((getpwnam_r(nptr, &pwd, pwdbuf, sizeof (pwdbuf)) == NULL) || (getspnam_r(nptr, &sp, spbuf, sizeof (spbuf)) == NULL)) { message(ERR, gettext("Unknown id: %s"), nptr); audit_failure(PW_FALSE, NULL, PAM_USER_UNKNOWN); closelog(); exit(1); } /* * Prompt for password if invoking user is not root or * if specified(new) user requires a password */ if (sp.sp_pwdp[0] == '\0' || getuid() == (uid_t)ROOT) goto ok; password = getpass(gettext("Password:")); if ((strcmp(sp.sp_pwdp, crypt(password, sp.sp_pwdp)) != 0)) { /* clear password file entry */ (void) memset((void *)spbuf, 0, sizeof (spbuf)); if (Sulog != NULL) log(Sulog, nptr, 0); /* log entry */ message(ERR, gettext("Sorry")); audit_failure(PW_FALSE, NULL, PAM_AUTH_ERR); if (dosyslog) syslog(LOG_CRIT, "'su %s' failed for %s on %s", pwd.pw_name, username, ttyn); closelog(); exit(2); } /* clear password file entry */ (void) memset((void *)spbuf, 0, sizeof (spbuf)); ok: /* update audit session in a non-pam environment */ update_audit(&pwd); if (dosyslog) syslog(getuid() == 0 ? LOG_INFO : LOG_NOTICE, "'su %s' succeeded for %s on %s", pwd.pw_name, username, ttyn); #endif /* DYNAMIC_SU */ audit_success(pw_change, &pwd); uid = pwd.pw_uid; gid = pwd.pw_gid; dir = strdup(pwd.pw_dir); shprog = strdup(pwd.pw_shell); name = strdup(pwd.pw_name); if (Sulog != NULL) log(Sulog, nptr, 1); /* log entry */ /* set user and group ids to specified user */ /* set the real (and effective) GID */ if (setgid(gid) == -1) { message(ERR, gettext("Invalid GID")); exit(2); } /* Initialize the supplementary group access list. */ if (!nptr) exit(2); if (initgroups(nptr, gid) == -1) { exit(2); } /* set the real (and effective) UID */ if (setuid(uid) == -1) { message(ERR, gettext("Invalid UID")); exit(2); } /* * If new user's shell field is neither NULL nor equal to /usr/bin/sh, * set: * * pshell = their shell * su = [-]last component of shell's pathname * * Otherwise, set the shell to /usr/bin/sh and set argv[0] to '[-]su'. */ if (shprog[0] != '\0' && strcmp(shell, shprog) != 0) { char *p; pshell = shprog; (void) strcpy(su, eflag ? "-" : ""); if ((p = strrchr(pshell, '/')) != NULL) (void) strlcat(su, p + 1, sizeof (su)); else (void) strlcat(su, pshell, sizeof (su)); } else { pshell = shell; (void) strcpy(su, eflag ? "-su" : "su"); } /* * set environment variables for new user; * arg0 for exec of shprog must now contain `-' * so that environment of new user is given */ if (eflag) { int j; char *var; if (strlen(dir) == 0) { (void) strcpy(dir, "/"); message(WARN, gettext("No directory! Using home=/")); } (void) strlcat(homedir, dir, sizeof (homedir)); (void) strlcat(logname, name, sizeof (logname)); if (hz = getenv("HZ")) (void) strlcat(hzname, hz, sizeof (hzname)); (void) strlcat(shelltyp, pshell, sizeof (shelltyp)); if (chdir(dir) < 0) { message(ERR, gettext("No directory!")); exit(1); } envinit[envidx = 0] = homedir; envinit[++envidx] = ((uid == (uid_t)ROOT) ? supath : path); envinit[++envidx] = logname; envinit[++envidx] = hzname; if ((term = getenv("TERM")) != NULL) { (void) strlcat(termtyp, term, sizeof (termtyp)); envinit[++envidx] = termtyp; } envinit[++envidx] = shelltyp; (void) strlcat(mail, name, sizeof (mail)); envinit[++envidx] = mail; /* * Fetch the relevant locale/TZ environment variables from * the inherited environment. * * We have a priority here for setting TZ. If TZ is set in * in the inherited environment, that value remains top * priority. If the file /etc/default/login has TIMEZONE set, * that has second highest priority. */ tznam[0] = '\0'; for (j = 0; initenv[j] != 0; j++) { if (initvar = getenv(initenv[j])) { /* * Skip over values beginning with '/' for * security. */ if (initvar[0] == '/') continue; if (strcmp(initenv[j], "TZ") == 0) { (void) strcpy(tznam, "TZ="); (void) strlcat(tznam, initvar, sizeof (tznam)); } else { var = (char *) malloc(strlen(initenv[j]) + strlen(initvar) + 2); (void) strcpy(var, initenv[j]); (void) strcat(var, "="); (void) strcat(var, initvar); envinit[++envidx] = var; } } } /* * Check if TZ was found. If not then try to read it from * /etc/default/login. */ if (tznam[0] == '\0') { if (defopen(DEFAULT_LOGIN) == 0) { if (initvar = defread("TIMEZONE=")) { (void) strcpy(tznam, "TZ="); (void) strlcat(tznam, initvar, sizeof (tznam)); } (void) defopen(NULL); } } if (tznam[0] != '\0') envinit[++envidx] = tznam; #ifdef DYNAMIC_SU /* * set the PAM environment variables - * check for legal environment variables */ if ((pam_env = pam_getenvlist(pamh)) != 0) { while (pam_env[idx] != 0) { if (envidx + 2 < ELIM && legalenvvar(pam_env[idx])) { envinit[++envidx] = pam_env[idx]; } idx++; } } #endif /* DYNAMIC_SU */ envinit[++envidx] = NULL; environ = envinit; } else { char **pp = environ, **qq, *p; while ((p = *pp) != NULL) { if (*p == 'L' && p[1] == 'D' && p[2] == '_') { for (qq = pp; (*qq = qq[1]) != NULL; qq++) ; /* pp is not advanced */ } else { pp++; } } } #ifdef DYNAMIC_SU if (pamh) (void) pam_end(pamh, PAM_SUCCESS); #endif /* DYNAMIC_SU */ /* * if new user is root: * if CONSOLE defined, log entry there; * if eflag not set, change environment to that of root. */ if (uid == (uid_t)ROOT) { if (Console != NULL) if (strcmp(ttyn, Console) != 0) { (void) signal(SIGALRM, to); (void) alarm(30); log(Console, nptr, 1); (void) alarm(0); } if (!eflag) envalt(); } /* * Default for SIGCPU and SIGXFSZ. Shells inherit * signal disposition from parent. And the * shells should have default dispositions for these * signals. */ (void) signal(SIGXCPU, SIG_DFL); (void) signal(SIGXFSZ, SIG_DFL); #ifdef DYNAMIC_SU if (embedded) { (void) puts("SUCCESS"); /* * After this point, we're no longer talking the * embedded_su protocol, so turn it off. */ embedded = B_FALSE; } #endif /* DYNAMIC_SU */ /* * if additional arguments, exec shell program with array * of pointers to arguments: * -> if shell = default, then su = [-]su * -> if shell != default, then su = [-]last component of * shell's pathname * * if no additional arguments, exec shell with arg0 of su * where: * -> if shell = default, then su = [-]su * -> if shell != default, then su = [-]last component of * shell's pathname */ if (argc > 2) { argv[1] = su; (void) execv(pshell, &argv[1]); } else (void) execl(pshell, su, 0); /* * Try to clean up after an administrator who has made a mistake * configuring root's shell; if root's shell is other than /sbin/sh, * try exec'ing /sbin/sh instead. */ if ((uid == (uid_t)ROOT) && (strcmp(name, "root") == 0) && (strcmp(safe_shell, pshell) != 0)) { message(WARN, gettext("No shell %s. Trying fallback shell %s."), pshell, safe_shell); if (eflag) { (void) strcpy(su, "-sh"); (void) strlcpy(shelltyp + strlen("SHELL="), safe_shell, sizeof (shelltyp) - strlen("SHELL=")); } else { (void) strcpy(su, "sh"); } if (argc > 2) { argv[1] = su; (void) execv(safe_shell, &argv[1]); } else { (void) execl(safe_shell, su, 0); } message(ERR, gettext("Couldn't exec fallback shell %s: %s"), safe_shell, strerror(errno)); } else { message(ERR, gettext("No shell")); } return (3); } /* * Environment altering routine - * This routine is called when a user is su'ing to root * without specifying the - flag. * The user's PATH and PS1 variables are reset * to the correct value for root. * All of the user's other environment variables retain * their current values after the su (if they are exported). */ static void envalt(void) { /* * If user has PATH variable in their environment, change its value * to /bin:/etc:/usr/bin ; * if user does not have PATH variable, add it to the user's * environment; * if either of the above fail, an error message is printed. */ if (putenv(supath) != 0) { message(ERR, gettext("unable to obtain memory to expand environment")); exit(4); } /* * If user has PROMPT variable in their environment, change its value * to # ; * if user does not have PROMPT variable, add it to the user's * environment; * if either of the above fail, an error message is printed. */ if (putenv(suprmt) != 0) { message(ERR, gettext("unable to obtain memory to expand environment")); exit(4); } } /* * Logging routine - * where = SULOG or CONSOLE * towho = specified user ( user being su'ed to ) * how = 0 if su attempt failed; 1 if su attempt succeeded */ static void log(char *where, char *towho, int how) { FILE *logf; time_t now; struct tm *tmp; /* * open SULOG or CONSOLE - if open fails, return */ if ((logf = fopen(where, "a")) == NULL) return; now = time(0); tmp = localtime(&now); /* * write entry into SULOG or onto CONSOLE - if write fails, return */ (void) fprintf(logf, "SU %.2d/%.2d %.2d:%.2d %c %s %s-%s\n", tmp->tm_mon + 1, tmp->tm_mday, tmp->tm_hour, tmp->tm_min, how ? '+' : '-', ttyn + sizeof ("/dev/") - 1, username, towho); (void) fclose(logf); /* close SULOG or CONSOLE */ } /*ARGSUSED*/ static void to(int sig) {} /* * audit_success - audit successful su * * Entry process audit context established -- i.e., pam_setcred() * or equivalent called. * pw_change = PW_TRUE, if successful password change audit * required. * pwd = passwd entry for new user. */ static void audit_success(int pw_change, struct passwd *pwd) { adt_session_data_t *ah = NULL; adt_event_data_t *event; if (adt_start_session(&ah, NULL, ADT_USE_PROC_DATA) != 0) { syslog(LOG_AUTH | LOG_ALERT, "adt_start_session(ADT_su): %m"); return; } /* since proc uid/gid not yet updated */ if (adt_set_user(ah, pwd->pw_uid, pwd->pw_gid, pwd->pw_uid, pwd->pw_gid, NULL, ADT_USER) != 0) { syslog(LOG_AUTH | LOG_ERR, "adt_set_user(ADT_su, ADT_FAILURE): %m"); } if ((event = adt_alloc_event(ah, ADT_su)) == NULL) { syslog(LOG_AUTH | LOG_ALERT, "adt_alloc_event(ADT_su): %m"); } else if (adt_put_event(event, ADT_SUCCESS, ADT_SUCCESS) != 0) { syslog(LOG_AUTH | LOG_ALERT, "adt_put_event(ADT_su, ADT_SUCCESS): %m"); } if (pw_change == PW_TRUE) { /* Also audit password change */ adt_free_event(event); if ((event = adt_alloc_event(ah, ADT_passwd)) == NULL) { syslog(LOG_AUTH | LOG_ALERT, "adt_alloc_event(ADT_passwd): %m"); } else if (adt_put_event(event, ADT_SUCCESS, ADT_SUCCESS) != 0) { syslog(LOG_AUTH | LOG_ALERT, "adt_put_event(ADT_passwd, ADT_SUCCESS): %m"); } } adt_free_event(event); } /* * audit_failure - audit failed su * * Entry New audit context not set. * pw_change == PW_FALSE, if no password change requested. * PW_FAILED, if failed password change audit * required. * pwent = NULL, or password entry to use. * pamerr = PAM error code; reason for failure. */ static void audit_failure(int pw_change, struct passwd *pwd, int pamerr) { adt_session_data_t *ah; /* audit session handle */ adt_event_data_t *event; /* event to generate */ if (adt_start_session(&ah, NULL, ADT_USE_PROC_DATA) != 0) { syslog(LOG_AUTH | LOG_ALERT, "adt_start_session(ADT_su, ADT_FAILURE): %m"); return; } if (pwd != NULL) { /* target user authenticated, merge audit state */ if (adt_set_user(ah, pwd->pw_uid, pwd->pw_gid, pwd->pw_uid, pwd->pw_gid, NULL, ADT_UPDATE) != 0) { syslog(LOG_AUTH | LOG_ERR, "adt_set_user(ADT_su, ADT_FAILURE): %m"); } } if ((event = adt_alloc_event(ah, ADT_su)) == NULL) { syslog(LOG_AUTH | LOG_ALERT, "adt_alloc_event(ADT_su, ADT_FAILURE): %m"); return; } else if (adt_put_event(event, ADT_FAILURE, ADT_FAIL_PAM + pamerr) != 0) { syslog(LOG_AUTH | LOG_ALERT, "adt_put_event(ADT_su(ADT_FAIL, %s): %m", pam_strerror(pamh, pamerr)); } if (pw_change != PW_FALSE) { /* Also audit password change failed */ adt_free_event(event); if ((event = adt_alloc_event(ah, ADT_passwd)) == NULL) { syslog(LOG_AUTH | LOG_ALERT, "adt_alloc_event(ADT_passwd): %m"); } else if (adt_put_event(event, ADT_FAILURE, ADT_FAIL_PAM + pamerr) != 0) { syslog(LOG_AUTH | LOG_ALERT, "adt_put_event(ADT_passwd, ADT_FAILURE): %m"); } } adt_free_event(event); } #ifdef DYNAMIC_SU /* * su_conv(): * This is the conv (conversation) function called from * a PAM authentication module to print error messages * or garner information from the user. */ /*ARGSUSED*/ static int su_conv(int num_msg, struct pam_message **msg, struct pam_response **response, void *appdata_ptr) { struct pam_message *m; struct pam_response *r; char *temp; int k; char respbuf[PAM_MAX_RESP_SIZE]; if (num_msg <= 0) return (PAM_CONV_ERR); *response = (struct pam_response *)calloc(num_msg, sizeof (struct pam_response)); if (*response == NULL) return (PAM_BUF_ERR); k = num_msg; m = *msg; r = *response; while (k--) { switch (m->msg_style) { case PAM_PROMPT_ECHO_OFF: errno = 0; temp = getpassphrase(m->msg); if (errno == EINTR) return (PAM_CONV_ERR); if (temp != NULL) { r->resp = strdup(temp); if (r->resp == NULL) { freeresponse(num_msg, response); return (PAM_BUF_ERR); } } break; case PAM_PROMPT_ECHO_ON: if (m->msg != NULL) { (void) fputs(m->msg, stdout); } (void) fgets(respbuf, sizeof (respbuf), stdin); temp = strchr(respbuf, '\n'); if (temp != NULL) *temp = '\0'; r->resp = strdup(respbuf); if (r->resp == NULL) { freeresponse(num_msg, response); return (PAM_BUF_ERR); } break; case PAM_ERROR_MSG: if (m->msg != NULL) { (void) fputs(m->msg, stderr); (void) fputs("\n", stderr); } break; case PAM_TEXT_INFO: if (m->msg != NULL) { (void) fputs(m->msg, stdout); (void) fputs("\n", stdout); } break; default: break; } m++; r++; } return (PAM_SUCCESS); } /* * emb_su_conv(): * This is the conv (conversation) function called from * a PAM authentication module to print error messages * or garner information from the user. * This version is used for embedded_su. */ /*ARGSUSED*/ static int emb_su_conv(int num_msg, struct pam_message **msg, struct pam_response **response, void *appdata_ptr) { struct pam_message *m; struct pam_response *r; char *temp; int k; char respbuf[PAM_MAX_RESP_SIZE]; if (num_msg <= 0) return (PAM_CONV_ERR); *response = (struct pam_response *)calloc(num_msg, sizeof (struct pam_response)); if (*response == NULL) return (PAM_BUF_ERR); /* First, send the prompts */ (void) printf("CONV %d\n", num_msg); k = num_msg; m = *msg; while (k--) { switch (m->msg_style) { case PAM_PROMPT_ECHO_OFF: (void) puts("PAM_PROMPT_ECHO_OFF"); goto msg_common; case PAM_PROMPT_ECHO_ON: (void) puts("PAM_PROMPT_ECHO_ON"); goto msg_common; case PAM_ERROR_MSG: (void) puts("PAM_ERROR_MSG"); goto msg_common; case PAM_TEXT_INFO: (void) puts("PAM_TEXT_INFO"); /* fall through to msg_common */ msg_common: if (m->msg == NULL) quotemsg(NULL); else quotemsg("%s", m->msg); break; default: break; } m++; } /* Next, collect the responses */ k = num_msg; m = *msg; r = *response; while (k--) { switch (m->msg_style) { case PAM_PROMPT_ECHO_OFF: case PAM_PROMPT_ECHO_ON: (void) fgets(respbuf, sizeof (respbuf), stdin); temp = strchr(respbuf, '\n'); if (temp != NULL) *temp = '\0'; r->resp = strdup(respbuf); if (r->resp == NULL) { freeresponse(num_msg, response); return (PAM_BUF_ERR); } break; case PAM_ERROR_MSG: case PAM_TEXT_INFO: break; default: break; } m++; r++; } return (PAM_SUCCESS); } static void freeresponse(int num_msg, struct pam_response **response) { struct pam_response *r; int i; /* free responses */ r = *response; for (i = 0; i < num_msg; i++, r++) { if (r->resp != NULL) { /* Zap it in case it's a password */ (void) memset(r->resp, '\0', strlen(r->resp)); free(r->resp); } } free(*response); *response = NULL; } /* * Print a message, applying quoting for lines starting with '.'. * * I18n note: \n is "safe" in all locales, and all locales use * a high-bit-set character to start multibyte sequences, so * scanning for a \n followed by a '.' is safe. */ static void quotemsg(char *fmt, ...) { if (fmt != NULL) { char *msg; char *p; boolean_t bol; va_list v; va_start(v, fmt); msg = alloc_vsprintf(fmt, v); va_end(v); bol = B_TRUE; for (p = msg; *p != '\0'; p++) { if (bol) { if (*p == '.') (void) putchar('.'); bol = B_FALSE; } (void) putchar(*p); if (*p == '\n') bol = B_TRUE; } (void) putchar('\n'); free(msg); } (void) putchar('.'); (void) putchar('\n'); } /* * validate - Check that the account is valid for switching to. */ static void validate(char *usernam, int *pw_change) { int error; int flag = 0; int tries; if (passreq) flag = PAM_DISALLOW_NULL_AUTHTOK; if ((error = pam_acct_mgmt(pamh, flag)) != PAM_SUCCESS) { if (Sulog != NULL) log(Sulog, pwd.pw_name, 0); /* log entry */ if (error == PAM_NEW_AUTHTOK_REQD) { tries = 0; message(ERR, gettext("Password for user " "'%s' has expired"), pwd.pw_name); while ((error = pam_chauthtok(pamh, 0)) != PAM_SUCCESS) { if ((error == PAM_AUTHTOK_ERR || error == PAM_TRY_AGAIN) && (tries++ < DEF_ATTEMPTS)) { continue; } message(ERR, gettext("Sorry")); audit_failure(PW_FAILED, &pwd, error); if (dosyslog) syslog(LOG_CRIT, "'su %s' failed for %s on %s", pwd.pw_name, usernam, ttyn); closelog(); exit(1); } *pw_change = PW_TRUE; return; } else { message(ERR, gettext("Sorry")); audit_failure(PW_FALSE, &pwd, error); if (dosyslog) syslog(LOG_CRIT, "'su %s' failed for %s on %s", pwd.pw_name, usernam, ttyn); closelog(); exit(3); } } } static char *illegal[] = { "SHELL=", "HOME=", "LOGNAME=", #ifndef NO_MAIL "MAIL=", #endif "CDPATH=", "IFS=", "PATH=", "TZ=", "HZ=", "TERM=", 0 }; /* * legalenvvar - can PAM modules insert this environmental variable? */ static int legalenvvar(char *s) { register char **p; for (p = illegal; *p; p++) if (strncmp(s, *p, strlen(*p)) == 0) return (0); if (s[0] == 'L' && s[1] == 'D' && s[2] == '_') return (0); return (1); } /* * The embedded_su protocol allows the client application to supply * an initialization block terminated by a line with just a "." on it. * * This initialization block is currently unused, reserved for future * expansion. Ignore it. This is made very slightly more complex by * the desire to cleanly ignore input lines of any length, while still * correctly detecting a line with just a "." on it. * * I18n note: It appears that none of the Solaris-supported locales * use 0x0a for any purpose other than newline, so looking for '\n' * seems safe. * All locales use high-bit-set leadin characters for their multi-byte * sequences, so a line consisting solely of ".\n" is what it appears * to be. */ static void readinitblock(void) { char buf[100]; boolean_t bol; bol = B_TRUE; for (;;) { if (fgets(buf, sizeof (buf), stdin) == NULL) return; if (bol && strcmp(buf, ".\n") == 0) return; bol = (strchr(buf, '\n') != NULL); } } #else /* !DYNAMIC_SU */ static void update_audit(struct passwd *pwd) { adt_session_data_t *ah; /* audit session handle */ if (adt_start_session(&ah, NULL, ADT_USE_PROC_DATA) != 0) { message(ERR, gettext("Sorry")); if (dosyslog) syslog(LOG_CRIT, "'su %s' failed for %s " "cannot start audit session %m", pwd->pw_name, username); closelog(); exit(2); } if (adt_set_user(ah, pwd->pw_uid, pwd->pw_gid, pwd->pw_uid, pwd->pw_gid, NULL, ADT_UPDATE) != 0) { if (dosyslog) syslog(LOG_CRIT, "'su %s' failed for %s " "cannot update audit session %m", pwd->pw_name, username); closelog(); exit(2); } } #endif /* DYNAMIC_SU */ /* * Report an error, either a fatal one, a warning, or a usage message, * depending on the mode parameter. */ /*ARGSUSED*/ static void message(enum messagemode mode, char *fmt, ...) { char *s; va_list v; va_start(v, fmt); s = alloc_vsprintf(fmt, v); va_end(v); #ifdef DYNAMIC_SU if (embedded) { if (mode == WARN) { (void) printf("CONV 1\n"); (void) printf("PAM_ERROR_MSG\n"); } else { /* ERR, USAGE */ (void) printf("ERROR\n"); } if (mode == USAGE) { quotemsg("%s", s); } else { /* ERR, WARN */ quotemsg("%s: %s", myname, s); } } else { #endif /* DYNAMIC_SU */ if (mode == USAGE) { (void) fprintf(stderr, "%s\n", s); } else { /* ERR, WARN */ (void) fprintf(stderr, "%s: %s\n", myname, s); } #ifdef DYNAMIC_SU } #endif /* DYNAMIC_SU */ free(s); } /* * Return a pointer to the last path component of a. */ static char * tail(char *a) { char *p; p = strrchr(a, '/'); if (p == NULL) p = a; else p++; /* step over the '/' */ return (p); } static char * alloc_vsprintf(const char *fmt, va_list ap1) { va_list ap2; int n; char buf[1]; char *s; /* * We need to scan the argument list twice. Save off a copy * of the argument list pointer(s) for the second pass. Note that * we are responsible for va_end'ing our copy. */ va_copy(ap2, ap1); /* * vsnprintf into a dummy to get a length. One might * think that passing 0 as the length to snprintf would * do what we want, but it's defined not to. * * Perhaps we should sprintf into a 100 character buffer * or something like that, to avoid two calls to snprintf * in most cases. */ n = vsnprintf(buf, sizeof (buf), fmt, ap2); va_end(ap2); /* * Allocate an appropriately-sized buffer. */ s = malloc(n + 1); if (s == NULL) { perror("malloc"); exit(4); } (void) vsnprintf(s, n+1, fmt, ap1); return (s); }