X-Git-Url: http://andersk.mit.edu/gitweb/gssapi-openssh.git/blobdiff_plain/d03f42626b290c7c9839e1ecb27dfb069e76a396..97f0f2cce4eeef89047da2228a6bea6274065f1e:/openssh/auth.c diff --git a/openssh/auth.c b/openssh/auth.c index ac5b3c2..70bf48a 100644 --- a/openssh/auth.c +++ b/openssh/auth.c @@ -23,14 +23,14 @@ */ #include "includes.h" -RCSID("$OpenBSD: auth.c,v 1.45 2002/09/20 18:41:29 stevesk Exp $"); +RCSID("$OpenBSD: auth.c,v 1.57 2005/01/22 08:17:59 dtucker Exp $"); #ifdef HAVE_LOGIN_H #include #endif -#if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) +#ifdef USE_SHADOW #include -#endif /* defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) */ +#endif #ifdef HAVE_LIBGEN_H #include @@ -47,13 +47,15 @@ RCSID("$OpenBSD: auth.c,v 1.45 2002/09/20 18:41:29 stevesk Exp $"); #include "buffer.h" #include "bufaux.h" #include "uidswap.h" -#include "tildexpand.h" #include "misc.h" #include "bufaux.h" #include "packet.h" +#include "loginrec.h" +#include "monitor_wrap.h" /* import */ extern ServerOptions options; +extern Buffer loginmsg; /* Debugging messages */ Buffer auth_debug; @@ -72,55 +74,57 @@ int allowed_user(struct passwd * pw) { struct stat st; - const char *hostname = NULL, *ipaddr = NULL; + const char *hostname = NULL, *ipaddr = NULL, *passwd = NULL; char *shell; int i; -#ifdef WITH_AIXAUTHENTICATE - char *loginmsg; -#endif /* WITH_AIXAUTHENTICATE */ -#if !defined(USE_PAM) && defined(HAVE_SHADOW_H) && \ - !defined(DISABLE_SHADOW) && defined(HAS_SHADOW_EXPIRE) - struct spwd *spw; +#ifdef USE_SHADOW + struct spwd *spw = NULL; +#endif /* Shouldn't be called if pw is NULL, but better safe than sorry... */ if (!pw || !pw->pw_name) return 0; -#define DAY (24L * 60 * 60) /* 1 day in seconds */ - spw = getspnam(pw->pw_name); - if (spw != NULL) { - time_t today = time(NULL) / DAY; - debug3("allowed_user: today %d sp_expire %d sp_lstchg %d" - " sp_max %d", (int)today, (int)spw->sp_expire, - (int)spw->sp_lstchg, (int)spw->sp_max); +#ifdef USE_SHADOW + if (!options.use_pam) + spw = getspnam(pw->pw_name); +#ifdef HAS_SHADOW_EXPIRE + if (!options.use_pam && spw != NULL && auth_shadow_acctexpired(spw)) + return 0; +#endif /* HAS_SHADOW_EXPIRE */ +#endif /* USE_SHADOW */ - /* - * We assume account and password expiration occurs the - * day after the day specified. - */ - if (spw->sp_expire != -1 && today > spw->sp_expire) { - log("Account %.100s has expired", pw->pw_name); - return 0; - } + /* grab passwd field for locked account check */ +#ifdef USE_SHADOW + if (spw != NULL) + passwd = spw->sp_pwdp; +#else + passwd = pw->pw_passwd; +#endif - if (spw->sp_lstchg == 0) { - log("User %.100s password has expired (root forced)", - pw->pw_name); - return 0; - } + /* check for locked account */ + if (!options.use_pam && passwd && *passwd) { + int locked = 0; - if (spw->sp_max != -1 && - today > spw->sp_lstchg + spw->sp_max) { - log("User %.100s password has expired (password aged)", +#ifdef LOCKED_PASSWD_STRING + if (strcmp(passwd, LOCKED_PASSWD_STRING) == 0) + locked = 1; +#endif +#ifdef LOCKED_PASSWD_PREFIX + if (strncmp(passwd, LOCKED_PASSWD_PREFIX, + strlen(LOCKED_PASSWD_PREFIX)) == 0) + locked = 1; +#endif +#ifdef LOCKED_PASSWD_SUBSTR + if (strstr(passwd, LOCKED_PASSWD_SUBSTR)) + locked = 1; +#endif + if (locked) { + logit("User %.100s not allowed because account is locked", pw->pw_name); return 0; } } -#else - /* Shouldn't be called if pw is NULL, but better safe than sorry... */ - if (!pw || !pw->pw_name) - return 0; -#endif /* * Get the shell from the password data. An empty shell field is @@ -130,19 +134,19 @@ allowed_user(struct passwd * pw) /* deny if shell does not exists or is not executable */ if (stat(shell, &st) != 0) { - log("User %.100s not allowed because shell %.100s does not exist", + logit("User %.100s not allowed because shell %.100s does not exist", pw->pw_name, shell); return 0; } if (S_ISREG(st.st_mode) == 0 || (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) { - log("User %.100s not allowed because shell %.100s is not executable", + logit("User %.100s not allowed because shell %.100s is not executable", pw->pw_name, shell); return 0; } if (options.num_deny_users > 0 || options.num_allow_users > 0) { - hostname = get_canonical_hostname(options.verify_reverse_mapping); + hostname = get_canonical_hostname(options.use_dns); ipaddr = get_remote_ipaddr(); } @@ -151,8 +155,9 @@ allowed_user(struct passwd * pw) for (i = 0; i < options.num_deny_users; i++) if (match_user(pw->pw_name, hostname, ipaddr, options.deny_users[i])) { - log("User %.100s not allowed because listed in DenyUsers", - pw->pw_name); + logit("User %.100s from %.100s not allowed " + "because listed in DenyUsers", + pw->pw_name, hostname); return 0; } } @@ -164,16 +169,16 @@ allowed_user(struct passwd * pw) break; /* i < options.num_allow_users iff we break for loop */ if (i >= options.num_allow_users) { - log("User %.100s not allowed because not listed in AllowUsers", - pw->pw_name); + logit("User %.100s from %.100s not allowed because " + "not listed in AllowUsers", pw->pw_name, hostname); return 0; } } if (options.num_deny_groups > 0 || options.num_allow_groups > 0) { /* Get the user's group access list (primary and supplementary) */ if (ga_init(pw->pw_name, pw->pw_gid) == 0) { - log("User %.100s not allowed because not in any group", - pw->pw_name); + logit("User %.100s from %.100s not allowed because " + "not in any group", pw->pw_name, hostname); return 0; } @@ -182,8 +187,9 @@ allowed_user(struct passwd * pw) if (ga_match(options.deny_groups, options.num_deny_groups)) { ga_free(); - log("User %.100s not allowed because a group is listed in DenyGroups", - pw->pw_name); + logit("User %.100s from %.100s not allowed " + "because a group is listed in DenyGroups", + pw->pw_name, hostname); return 0; } /* @@ -194,42 +200,23 @@ allowed_user(struct passwd * pw) if (!ga_match(options.allow_groups, options.num_allow_groups)) { ga_free(); - log("User %.100s not allowed because none of user's groups are listed in AllowGroups", - pw->pw_name); + logit("User %.100s from %.100s not allowed " + "because none of user's groups are listed " + "in AllowGroups", pw->pw_name, hostname); return 0; } ga_free(); } -#ifdef WITH_AIXAUTHENTICATE - if (loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) { - if (loginmsg && *loginmsg) { - /* Remove embedded newlines (if any) */ - char *p; - for (p = loginmsg; *p; p++) { - if (*p == '\n') - *p = ' '; - } - /* Remove trailing newline */ - *--p = '\0'; - log("Login restricted for %s: %.100s", pw->pw_name, loginmsg); - } +#ifdef CUSTOM_SYS_AUTH_ALLOWED_USER + if (!sys_auth_allowed_user(pw, &loginmsg)) return 0; - } -#endif /* WITH_AIXAUTHENTICATE */ +#endif /* We found no reason not to let this user try to log on... */ return 1; } -Authctxt * -authctxt_new(void) -{ - Authctxt *authctxt = xmalloc(sizeof(*authctxt)); - memset(authctxt, 0, sizeof(*authctxt)); - return authctxt; -} - void auth_log(Authctxt *authctxt, int authenticated, char *method, char *info) { @@ -239,9 +226,9 @@ auth_log(Authctxt *authctxt, int authenticated, char *method, char *info) /* Raise logging level */ if (authenticated == 1 || !authctxt->valid || - authctxt->failures >= AUTH_FAIL_LOG || + authctxt->failures >= options.max_authtries / 2 || strcmp(method, "password") == 0) - authlog = log; + authlog = logit; if (authctxt->postponed) authmsg = "Postponed"; @@ -251,19 +238,59 @@ auth_log(Authctxt *authctxt, int authenticated, char *method, char *info) authlog("%s %s for %s%.100s from %.200s port %d%s", authmsg, method, - authctxt->valid ? "" : "illegal user ", - (authctxt->user[0]) ? authctxt->user : "", + authctxt->valid ? "" : "invalid user ", + (authctxt->user && authctxt->user[0]) ? + authctxt->user : "", get_remote_ipaddr(), get_remote_port(), info); -#ifdef WITH_AIXAUTHENTICATE - if (authenticated == 0 && strcmp(method, "password") == 0) - loginfailed(authctxt->user, - get_canonical_hostname(options.verify_reverse_mapping), - "ssh"); -#endif /* WITH_AIXAUTHENTICATE */ +#ifdef CUSTOM_FAILED_LOGIN + if (authenticated == 0 && !authctxt->postponed && + (strcmp(method, "password") == 0 || + strncmp(method, "keyboard-interactive", 20) == 0 || + strcmp(method, "challenge-response") == 0)) + record_failed_login(authctxt->user, + get_canonical_hostname(options.use_dns), "ssh"); +#endif +#ifdef SSH_AUDIT_EVENTS + if (authenticated == 0 && !authctxt->postponed) { + ssh_audit_event_t event; + debug3("audit failed auth attempt, method %s euid %d", + method, (int)geteuid()); + /* + * Because the auth loop is used in both monitor and slave, + * we must be careful to send each event only once and with + * enough privs to write the event. + */ + event = audit_classify_auth(method); + switch(event) { + case SSH_AUTH_FAIL_NONE: + case SSH_AUTH_FAIL_PASSWD: + case SSH_AUTH_FAIL_KBDINT: + if (geteuid() == 0) + audit_event(event); + break; + case SSH_AUTH_FAIL_PUBKEY: + case SSH_AUTH_FAIL_HOSTBASED: + case SSH_AUTH_FAIL_GSSAPI: + /* + * This is required to handle the case where privsep + * is enabled but it's root logging in, since + * use_privsep won't be cleared until after a + * successful login. + */ + if (geteuid() == 0) + audit_event(event); + else + PRIVSEP(audit_event(event)); + break; + default: + error("unknown authentication audit event %d", event); + } + } +#endif } /* @@ -282,12 +309,12 @@ auth_root_allowed(char *method) break; case PERMIT_FORCED_ONLY: if (forced_command) { - log("Root login accepted for forced command."); + logit("Root login accepted for forced command."); return 1; } break; } - log("ROOT LOGIN REFUSED FROM %.200s", get_remote_ipaddr()); + logit("ROOT LOGIN REFUSED FROM %.200s", get_remote_ipaddr()); return 0; } @@ -379,7 +406,7 @@ check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host, (stat(user_hostfile, &st) == 0) && ((st.st_uid != 0 && st.st_uid != pw->pw_uid) || (st.st_mode & 022) != 0)) { - log("Authentication refused for %.100s: " + logit("Authentication refused for %.100s: " "bad owner or modes for %.200s", pw->pw_name, user_hostfile); } else { @@ -417,6 +444,7 @@ secure_filename(FILE *f, const char *file, struct passwd *pw, uid_t uid = pw->pw_uid; char buf[MAXPATHLEN], homedir[MAXPATHLEN]; char *cp; + int comparehome = 0; struct stat st; if (realpath(file, buf) == NULL) { @@ -424,11 +452,8 @@ secure_filename(FILE *f, const char *file, struct passwd *pw, strerror(errno)); return -1; } - if (realpath(pw->pw_dir, homedir) == NULL) { - snprintf(err, errlen, "realpath %s failed: %s", pw->pw_dir, - strerror(errno)); - return -1; - } + if (realpath(pw->pw_dir, homedir) != NULL) + comparehome = 1; /* check the open file to avoid races */ if (fstat(fileno(f), &st) < 0 || @@ -457,7 +482,7 @@ secure_filename(FILE *f, const char *file, struct passwd *pw, } /* If are passed the homedir then we can stop */ - if (strcmp(homedir, buf) == 0) { + if (comparehome && strcmp(homedir, buf) == 0) { debug3("secure_filename: terminating check at '%s'", buf); break; @@ -485,8 +510,16 @@ getpwnamallow(const char *user) pw = getpwnam(user); if (pw == NULL) { - log("Illegal user %.100s from %.100s", - user, get_remote_ipaddr()); + logit("Invalid user %.100s from %.100s", + (user && user[0]) ? user : "", + get_remote_ipaddr()); +#ifdef CUSTOM_FAILED_LOGIN + record_failed_login(user, + get_canonical_hostname(options.use_dns), "ssh"); +#endif +#ifdef SSH_AUDIT_EVENTS + audit_event(SSH_INVALID_USER); +#endif /* SSH_AUDIT_EVENTS */ return (NULL); } if (!allowed_user(pw)) @@ -550,3 +583,24 @@ auth_debug_reset(void) auth_debug_init = 1; } } + +struct passwd * +fakepw(void) +{ + static struct passwd fake; + + memset(&fake, 0, sizeof(fake)); + fake.pw_name = "NOUSER"; + fake.pw_passwd = + "$2a$06$r3.juUaHZDlIbQaO2dS9FuYxL1W9M81R1Tc92PoSNmzvpEqLkLGrK"; + fake.pw_gecos = "NOUSER"; + fake.pw_uid = (uid_t)-1; + fake.pw_gid = (gid_t)-1; +#ifdef HAVE_PW_CLASS_IN_PASSWD + fake.pw_class = ""; +#endif + fake.pw_dir = "/nonexist"; + fake.pw_shell = "/nonexist"; + + return (&fake); +}