X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/bf4c5edccd18ff08d9b810429aca48630a40ab65..9a6fee8b2b42608a177803d2351d3cfe732910d8:/auth.c diff --git a/auth.c b/auth.c index efa7ee28..ba26034d 100644 --- a/auth.c +++ b/auth.c @@ -23,7 +23,7 @@ */ #include "includes.h" -RCSID("$OpenBSD: auth.c,v 1.32 2002/01/29 14:32:03 markus Exp $"); +RCSID("$OpenBSD: auth.c,v 1.46 2002/11/04 10:07:53 markus Exp $"); #ifdef HAVE_LOGIN_H #include @@ -48,10 +48,17 @@ RCSID("$OpenBSD: auth.c,v 1.32 2002/01/29 14:32:03 markus Exp $"); #include "bufaux.h" #include "uidswap.h" #include "tildexpand.h" +#include "misc.h" +#include "bufaux.h" +#include "packet.h" /* import */ extern ServerOptions options; +/* Debugging messages */ +Buffer auth_debug; +int auth_debug_init; + /* * Check if the user is allowed to log in via ssh. If user is listed * in DenyUsers or one of user's groups is listed in DenyGroups, false @@ -72,30 +79,46 @@ allowed_user(struct passwd * pw) char *loginmsg; #endif /* WITH_AIXAUTHENTICATE */ #if !defined(USE_PAM) && defined(HAVE_SHADOW_H) && \ - !defined(DISABLE_SHADOW) && defined(HAS_SHADOW_EXPIRE) + !defined(DISABLE_SHADOW) && defined(HAS_SHADOW_EXPIRE) struct spwd *spw; + time_t today; +#endif /* Shouldn't be called if pw is NULL, but better safe than sorry... */ if (!pw || !pw->pw_name) return 0; - spw = getspnam(pw->pw_name); - if (spw != NULL) { - int days = time(NULL) / 86400; +#if !defined(USE_PAM) && defined(HAVE_SHADOW_H) && \ + !defined(DISABLE_SHADOW) && defined(HAS_SHADOW_EXPIRE) +#define DAY (24L * 60 * 60) /* 1 day in seconds */ + if ((spw = getspnam(pw->pw_name)) != NULL) { + 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); - /* Check account expiry */ - if ((spw->sp_expire >= 0) && (days > spw->sp_expire)) + /* + * We assume account and password expiration occurs the + * day after the day specified. + */ + if (spw->sp_expire != -1 && today > spw->sp_expire) { + logit("Account %.100s has expired", pw->pw_name); return 0; + } - /* Check password expiry */ - if ((spw->sp_lstchg >= 0) && (spw->sp_max >= 0) && - (days > (spw->sp_lstchg + spw->sp_max))) + if (spw->sp_lstchg == 0) { + logit("User %.100s password has expired (root forced)", + pw->pw_name); return 0; + } + + if (spw->sp_max != -1 && + today > spw->sp_lstchg + spw->sp_max) { + logit("User %.100s password has expired (password aged)", + 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 /* @@ -105,10 +128,17 @@ allowed_user(struct passwd * pw) shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; /* deny if shell does not exists or is not executable */ - if (stat(shell, &st) != 0) + if (stat(shell, &st) != 0) { + logit("User %.100s not allowed because shell %.100s does not exist", + pw->pw_name, shell); return 0; - if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)))) + } + if (S_ISREG(st.st_mode) == 0 || + (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) { + 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); @@ -119,8 +149,11 @@ allowed_user(struct passwd * pw) if (options.num_deny_users > 0) { for (i = 0; i < options.num_deny_users; i++) if (match_user(pw->pw_name, hostname, ipaddr, - options.deny_users[i])) + options.deny_users[i])) { + logit("User %.100s not allowed because listed in DenyUsers", + pw->pw_name); return 0; + } } /* Return false if AllowUsers isn't empty and user isn't listed there */ if (options.num_allow_users > 0) { @@ -129,19 +162,27 @@ allowed_user(struct passwd * pw) options.allow_users[i])) break; /* i < options.num_allow_users iff we break for loop */ - if (i >= options.num_allow_users) + if (i >= options.num_allow_users) { + logit("User %.100s not allowed because not listed in AllowUsers", + pw->pw_name); 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) + if (ga_init(pw->pw_name, pw->pw_gid) == 0) { + logit("User %.100s not allowed because not in any group", + pw->pw_name); return 0; + } /* Return false if one of user's groups is listed in DenyGroups */ if (options.num_deny_groups > 0) if (ga_match(options.deny_groups, options.num_deny_groups)) { ga_free(); + logit("User %.100s not allowed because a group is listed in DenyGroups", + pw->pw_name); return 0; } /* @@ -152,13 +193,23 @@ allowed_user(struct passwd * pw) if (!ga_match(options.allow_groups, options.num_allow_groups)) { ga_free(); + logit("User %.100s not allowed because none of user's groups are listed in AllowGroups", + pw->pw_name); return 0; } ga_free(); } #ifdef WITH_AIXAUTHENTICATE - if (loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) { + /* + * Don't check loginrestrictions() for root account (use + * PermitRootLogin to control logins via ssh), or if running as + * non-root user (since loginrestrictions will always fail). + */ + if ((pw->pw_uid != 0) && (geteuid() == 0) && + loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &loginmsg) != 0) { + int loginrestrict_errno = errno; + if (loginmsg && *loginmsg) { /* Remove embedded newlines (if any) */ char *p; @@ -168,9 +219,13 @@ allowed_user(struct passwd * pw) } /* Remove trailing newline */ *--p = '\0'; - log("Login restricted for %s: %.100s", pw->pw_name, loginmsg); + logit("Login restricted for %s: %.100s", pw->pw_name, + loginmsg); } - return 0; + /* Don't fail if /etc/nologin set */ + if (!(loginrestrict_errno == EPERM && + stat(_PATH_NOLOGIN, &st) == 0)) + return 0; } #endif /* WITH_AIXAUTHENTICATE */ @@ -197,7 +252,7 @@ auth_log(Authctxt *authctxt, int authenticated, char *method, char *info) !authctxt->valid || authctxt->failures >= AUTH_FAIL_LOG || strcmp(method, "password") == 0) - authlog = log; + authlog = logit; if (authctxt->postponed) authmsg = "Postponed"; @@ -212,6 +267,14 @@ auth_log(Authctxt *authctxt, int authenticated, char *method, char *info) 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 */ + } /* @@ -230,12 +293,12 @@ 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; } @@ -327,7 +390,7 @@ 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 { @@ -348,7 +411,7 @@ check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host, /* * Check a given file for security. This is defined as all components - * of the path to the file must either be owned by either the owner of + * of the path to the file must be owned by either the owner of * of the file or root and no directories must be group or world writable. * * XXX Should any specific check be done for sym links ? @@ -365,6 +428,7 @@ 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) { @@ -372,11 +436,8 @@ 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 || @@ -405,7 +466,7 @@ 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; @@ -419,3 +480,87 @@ secure_filename(FILE *f, const char *file, struct passwd *pw, } return 0; } + +struct passwd * +getpwnamallow(const char *user) +{ +#ifdef HAVE_LOGIN_CAP + extern login_cap_t *lc; +#ifdef BSD_AUTH + auth_session_t *as; +#endif +#endif + struct passwd *pw; + + pw = getpwnam(user); + if (pw == NULL) { + logit("Illegal user %.100s from %.100s", + user, get_remote_ipaddr()); +#ifdef WITH_AIXAUTHENTICATE + loginfailed(user, + get_canonical_hostname(options.verify_reverse_mapping), + "ssh"); +#endif + return (NULL); + } + if (!allowed_user(pw)) + return (NULL); +#ifdef HAVE_LOGIN_CAP + if ((lc = login_getclass(pw->pw_class)) == NULL) { + debug("unable to get login class: %s", user); + return (NULL); + } +#ifdef BSD_AUTH + if ((as = auth_open()) == NULL || auth_setpwd(as, pw) != 0 || + auth_approval(as, lc, pw->pw_name, "ssh") <= 0) { + debug("Approval failure for %s", user); + pw = NULL; + } + if (as != NULL) + auth_close(as); +#endif +#endif + if (pw != NULL) + return (pwcopy(pw)); + return (NULL); +} + +void +auth_debug_add(const char *fmt,...) +{ + char buf[1024]; + va_list args; + + if (!auth_debug_init) + return; + + va_start(args, fmt); + vsnprintf(buf, sizeof(buf), fmt, args); + va_end(args); + buffer_put_cstring(&auth_debug, buf); +} + +void +auth_debug_send(void) +{ + char *msg; + + if (!auth_debug_init) + return; + while (buffer_len(&auth_debug)) { + msg = buffer_get_string(&auth_debug, NULL); + packet_send_debug("%s", msg); + xfree(msg); + } +} + +void +auth_debug_reset(void) +{ + if (auth_debug_init) + buffer_clear(&auth_debug); + else { + buffer_init(&auth_debug); + auth_debug_init = 1; + } +}