summaryrefslogtreecommitdiff
path: root/crypto/openssh/auth1.c
diff options
context:
space:
mode:
Diffstat (limited to 'crypto/openssh/auth1.c')
-rw-r--r--crypto/openssh/auth1.c593
1 files changed, 0 insertions, 593 deletions
diff --git a/crypto/openssh/auth1.c b/crypto/openssh/auth1.c
deleted file mode 100644
index 38e807fa14c98..0000000000000
--- a/crypto/openssh/auth1.c
+++ /dev/null
@@ -1,593 +0,0 @@
-/*
- * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
- * All rights reserved
- *
- * $FreeBSD$
- */
-
-#include "includes.h"
-RCSID("$OpenBSD: auth1.c,v 1.2 2000/04/29 18:11:52 markus Exp $");
-
-#include "xmalloc.h"
-#include "rsa.h"
-#include "ssh.h"
-#include "packet.h"
-#include "buffer.h"
-#include "cipher.h"
-#include "mpaux.h"
-#include "servconf.h"
-#include "compat.h"
-#include "auth.h"
-#include "session.h"
-#include <login_cap.h>
-
-#ifdef KRB5
-extern krb5_context ssh_context;
-krb5_principal tkt_client = NULL; /* Principal from the received ticket.
-Also is used as an indication of succesful krb5 authentization. */
-#endif
-
-/* import */
-extern ServerOptions options;
-extern char *forced_command;
-
-/*
- * convert ssh auth msg type into description
- */
-char *
-get_authname(int type)
-{
- static char buf[1024];
- switch (type) {
- case SSH_CMSG_AUTH_PASSWORD:
- return "password";
- case SSH_CMSG_AUTH_RSA:
- return "rsa";
- case SSH_CMSG_AUTH_RHOSTS_RSA:
- return "rhosts-rsa";
- case SSH_CMSG_AUTH_RHOSTS:
- return "rhosts";
-#ifdef KRB4
- case SSH_CMSG_AUTH_KRB4:
- return "kerberosV4";
-#endif
-#ifdef KRB5
- case SSH_CMSG_AUTH_KRB5:
- return "kerberosV5";
-#endif /* KRB5 */
-#ifdef SKEY
- case SSH_CMSG_AUTH_TIS_RESPONSE:
- return "s/key";
-#endif
- }
- snprintf(buf, sizeof buf, "bad-auth-msg-%d", type);
- return buf;
-}
-
-/*
- * The user does not exist or access is denied,
- * but fake indication that authentication is needed.
- */
-void
-do_fake_authloop1(char *user)
-{
- int attempt = 0;
-
- log("Faking authloop for illegal user %.200s from %.200s port %d",
- user,
- get_remote_ipaddr(),
- get_remote_port());
-
- /* Indicate that authentication is needed. */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
-
- /*
- * Keep reading packets, and always respond with a failure. This is
- * to avoid disclosing whether such a user really exists.
- */
- for (attempt = 1;; attempt++) {
- /* Read a packet. This will not return if the client disconnects. */
- int plen;
- int type = packet_read(&plen);
-#ifdef SKEY
- unsigned int dlen;
- char *password, *skeyinfo;
- password = NULL;
- /* Try to send a fake s/key challenge. */
- if (options.skey_authentication == 1 &&
- (skeyinfo = skey_fake_keyinfo(user)) != NULL) {
- if (type == SSH_CMSG_AUTH_TIS) {
- packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE);
- packet_put_string(skeyinfo, strlen(skeyinfo));
- packet_send();
- packet_write_wait();
- continue;
- } else if (type == SSH_CMSG_AUTH_PASSWORD &&
- options.password_authentication &&
- (password = packet_get_string(&dlen)) != NULL &&
- dlen == 5 &&
- strncasecmp(password, "s/key", 5) == 0 ) {
- packet_send_debug(skeyinfo);
- }
- }
- if (password != NULL)
- xfree(password);
-#endif
- if (attempt > AUTH_FAIL_MAX)
- packet_disconnect(AUTH_FAIL_MSG, user);
-
- /*
- * Send failure. This should be indistinguishable from a
- * failed authentication.
- */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
- }
- /* NOTREACHED */
- abort();
-}
-
-/*
- * read packets and try to authenticate local user *pw.
- * return if authentication is successfull
- */
-void
-do_authloop(struct passwd * pw)
-{
- int attempt = 0;
- unsigned int bits;
- RSA *client_host_key;
- BIGNUM *n;
- char *client_user, *password;
- char user[1024];
- unsigned int dlen;
- int plen, nlen, elen;
- unsigned int ulen;
- int type = 0;
- void (*authlog) (const char *fmt,...) = verbose;
-#ifdef LOGIN_CAP
- login_cap_t *lc;
-#endif /* LOGIN_CAP */
-#if defined(LOGIN_CAP) || defined(LOGIN_ACCESS)
- const char *from_host, *from_ip;
-
- from_host = get_canonical_hostname();
- from_ip = get_remote_ipaddr();
-#endif /* LOGIN_CAP || LOGIN_ACCESS */
-#ifdef HAVE_LIBPAM
- int pam_retval;
-#endif /* HAVE_LIBPAM */
-#if 0
-#ifdef KRB5
- {
- krb5_error_code ret;
-
- ret = krb5_init_context(&ssh_context);
- if (ret)
- verbose("Error while initializing Kerberos V5.");
- krb5_init_ets(ssh_context);
-
- }
-#endif /* KRB5 */
-#endif
-
- /* Indicate that authentication is needed. */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
-
- for (attempt = 1;; attempt++) {
- int authenticated = 0;
- strlcpy(user, "", sizeof user);
-
- /* Get a packet from the client. */
- type = packet_read(&plen);
-
- /* Process the packet. */
- switch (type) {
-#ifdef AFS
- case SSH_CMSG_HAVE_KRB4_TGT:
- if (!options.krb4_tgt_passing) {
- /* packet_get_all(); */
- verbose("Kerberos v4 tgt passing disabled.");
- break;
- } else {
- /* Accept Kerberos v4 tgt. */
- char *tgt = packet_get_string(&dlen);
- packet_integrity_check(plen, 4 + dlen, type);
- if (!auth_krb4_tgt(pw, tgt))
- verbose("Kerberos v4 tgt REFUSED for %s", pw->pw_name);
- xfree(tgt);
- }
- continue;
-
- case SSH_CMSG_HAVE_AFS_TOKEN:
- if (!options.afs_token_passing || !k_hasafs()) {
- /* packet_get_all(); */
- verbose("AFS token passing disabled.");
- break;
- } else {
- /* Accept AFS token. */
- char *token_string = packet_get_string(&dlen);
- packet_integrity_check(plen, 4 + dlen, type);
- if (!auth_afs_token(pw, token_string))
- verbose("AFS token REFUSED for %s", pw->pw_name);
- xfree(token_string);
- }
- continue;
-#endif /* AFS */
-#ifdef KRB4
- case SSH_CMSG_AUTH_KRB4:
- if (!options.krb4_authentication) {
- /* packet_get_all(); */
- verbose("Kerberos v4 authentication disabled.");
- break;
- } else {
- /* Try Kerberos v4 authentication. */
- KTEXT_ST auth;
- char *tkt_user = NULL;
- char *kdata = packet_get_string((unsigned int *) &auth.length);
- packet_integrity_check(plen, 4 + auth.length, type);
-
- if (auth.length < MAX_KTXT_LEN)
- memcpy(auth.dat, kdata, auth.length);
- xfree(kdata);
-
- authenticated = auth_krb4(pw->pw_name, &auth, &tkt_user);
-
- if (authenticated) {
- snprintf(user, sizeof user, " tktuser %s", tkt_user);
- xfree(tkt_user);
- }
- }
- break;
-#endif /* KRB4 */
-#ifdef KRB5
- case SSH_CMSG_AUTH_KRB5:
- if (!options.krb5_authentication) {
- verbose("Kerberos v5 authentication disabled.");
- break;
- } else {
- krb5_data k5data;
-#if 0
- if (krb5_init_context(&ssh_context)) {
- verbose("Error while initializing Kerberos V5.");
- break;
- }
- krb5_init_ets(ssh_context);
-#endif
-
- k5data.data = packet_get_string(&k5data.length);
- packet_integrity_check(plen, 4 + k5data.length, type);
- if (auth_krb5(pw->pw_name, &k5data, &tkt_client)) {
- /* pw->name is passed just for logging purposes
- * */
- /* authorize client against .k5login */
- if (krb5_kuserok(ssh_context,
- tkt_client,
- pw->pw_name))
- authenticated = 1;
- }
- xfree(k5data.data);
- }
- break;
-#endif /* KRB5 */
-
- case SSH_CMSG_AUTH_RHOSTS:
- if (!options.rhosts_authentication) {
- verbose("Rhosts authentication disabled.");
- break;
- }
- /*
- * Get client user name. Note that we just have to
- * trust the client; this is one reason why rhosts
- * authentication is insecure. (Another is
- * IP-spoofing on a local network.)
- */
- client_user = packet_get_string(&ulen);
- packet_integrity_check(plen, 4 + ulen, type);
-
- /* Try to authenticate using /etc/hosts.equiv and
- .rhosts. */
- authenticated = auth_rhosts(pw, client_user);
-
- snprintf(user, sizeof user, " ruser %s", client_user);
- xfree(client_user);
- break;
-
- case SSH_CMSG_AUTH_RHOSTS_RSA:
- if (!options.rhosts_rsa_authentication) {
- verbose("Rhosts with RSA authentication disabled.");
- break;
- }
- /*
- * Get client user name. Note that we just have to
- * trust the client; root on the client machine can
- * claim to be any user.
- */
- client_user = packet_get_string(&ulen);
-
- /* Get the client host key. */
- client_host_key = RSA_new();
- if (client_host_key == NULL)
- fatal("RSA_new failed");
- client_host_key->e = BN_new();
- client_host_key->n = BN_new();
- if (client_host_key->e == NULL || client_host_key->n == NULL)
- fatal("BN_new failed");
- bits = packet_get_int();
- packet_get_bignum(client_host_key->e, &elen);
- packet_get_bignum(client_host_key->n, &nlen);
-
- if (bits != BN_num_bits(client_host_key->n))
- log("Warning: keysize mismatch for client_host_key: "
- "actual %d, announced %d", BN_num_bits(client_host_key->n), bits);
- packet_integrity_check(plen, (4 + ulen) + 4 + elen + nlen, type);
-
- authenticated = auth_rhosts_rsa(pw, client_user, client_host_key);
- RSA_free(client_host_key);
-
- snprintf(user, sizeof user, " ruser %s", client_user);
- xfree(client_user);
- break;
-
- case SSH_CMSG_AUTH_RSA:
- if (!options.rsa_authentication) {
- verbose("RSA authentication disabled.");
- break;
- }
- /* RSA authentication requested. */
- n = BN_new();
- packet_get_bignum(n, &nlen);
- packet_integrity_check(plen, nlen, type);
- authenticated = auth_rsa(pw, n);
- BN_clear_free(n);
- break;
-
- case SSH_CMSG_AUTH_PASSWORD:
- if (!options.password_authentication) {
- verbose("Password authentication disabled.");
- break;
- }
- /*
- * Read user password. It is in plain text, but was
- * transmitted over the encrypted channel so it is
- * not visible to an outside observer.
- */
- password = packet_get_string(&dlen);
- packet_integrity_check(plen, 4 + dlen, type);
-
- /* Try authentication with the password. */
- authenticated = auth_password(pw, password);
-
- memset(password, 0, strlen(password));
- xfree(password);
- break;
-
-#ifdef SKEY
- case SSH_CMSG_AUTH_TIS:
- debug("rcvd SSH_CMSG_AUTH_TIS");
- if (options.skey_authentication == 1) {
- char *skeyinfo = opie_keyinfo(pw->pw_name);
- if (skeyinfo == NULL) {
- debug("generating fake skeyinfo for %.100s.", pw->pw_name);
- skeyinfo = skey_fake_keyinfo(pw->pw_name);
- }
- if (skeyinfo != NULL) {
- /* we send our s/key- in tis-challenge messages */
- debug("sending challenge '%s'", skeyinfo);
- packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE);
- packet_put_string(skeyinfo, strlen(skeyinfo));
- packet_send();
- packet_write_wait();
- continue;
- }
- }
- break;
- case SSH_CMSG_AUTH_TIS_RESPONSE:
- debug("rcvd SSH_CMSG_AUTH_TIS_RESPONSE");
- if (options.skey_authentication == 1) {
- char *response = packet_get_string(&dlen);
- debug("skey response == '%s'", response);
- packet_integrity_check(plen, 4 + dlen, type);
- authenticated = (opie_haskey(pw->pw_name) == 0 &&
- opie_passverify(pw->pw_name, response) != -1);
- xfree(response);
- }
- break;
-#else
- case SSH_CMSG_AUTH_TIS:
- /* TIS Authentication is unsupported */
- log("TIS authentication unsupported.");
- break;
-#endif
-#ifdef KRB5
- case SSH_CMSG_HAVE_KRB5_TGT:
- /* Passing krb5 ticket */
- if (!options.krb5_tgt_passing
- /*|| !options.krb5_authentication */) {
-
- }
-
- if (tkt_client == NULL) {
- /* passing tgt without krb5 authentication */
- }
-
- {
- krb5_data tgt;
- tgt.data = packet_get_string(&tgt.length);
-
- if (!auth_krb5_tgt(pw->pw_name, &tgt, tkt_client))
- verbose ("Kerberos V5 TGT refused for %.100s", pw->pw_name);
- xfree(tgt.data);
-
- break;
- }
-#endif /* KRB5 */
-
- default:
- /*
- * Any unknown messages will be ignored (and failure
- * returned) during authentication.
- */
- log("Unknown message during authentication: type %d", type);
- break;
- }
-
- /*
- * Check if the user is logging in as root and root logins
- * are disallowed.
- * Note that root login is allowed for forced commands.
- */
- if (authenticated && pw->pw_uid == 0 && !options.permit_root_login) {
- if (forced_command) {
- log("Root login accepted for forced command.");
- } else {
- authenticated = 0;
- log("ROOT LOGIN REFUSED FROM %.200s",
- get_canonical_hostname());
- }
- }
-
-#ifdef LOGIN_CAP
- lc = login_getpwclass(pw);
- if (lc == NULL)
- lc = login_getclassbyname(NULL, pw);
- if (!auth_hostok(lc, from_host, from_ip)) {
- log("Denied connection for %.200s from %.200s [%.200s].",
- pw->pw_name, from_host, from_ip);
- packet_disconnect("Sorry, you are not allowed to connect.");
- }
- if (!auth_timeok(lc, time(NULL))) {
- log("LOGIN %.200s REFUSED (TIME) FROM %.200s",
- pw->pw_name, from_host);
- packet_disconnect("Logins not available right now.");
- }
- login_close(lc);
-#endif /* LOGIN_CAP */
-#ifdef LOGIN_ACCESS
- if (!login_access(pw->pw_name, from_host)) {
- log("Denied connection for %.200s from %.200s [%.200s].",
- pw->pw_name, from_host, from_ip);
- packet_disconnect("Sorry, you are not allowed to connect.");
- }
-#endif /* LOGIN_ACCESS */
-
- if (pw->pw_uid == 0)
- log("ROOT LOGIN as '%.100s' from %.100s",
- pw->pw_name, get_canonical_hostname());
-
- /* Raise logging level */
- if (authenticated ||
- attempt == AUTH_FAIL_LOG ||
- type == SSH_CMSG_AUTH_PASSWORD)
- authlog = log;
-
- authlog("%s %s for %.200s from %.200s port %d%s",
- authenticated ? "Accepted" : "Failed",
- get_authname(type),
- pw->pw_uid == 0 ? "ROOT" : pw->pw_name,
- get_remote_ipaddr(),
- get_remote_port(),
- user);
-
- if (authenticated)
- return;
-
- if (attempt > AUTH_FAIL_MAX)
- packet_disconnect(AUTH_FAIL_MSG, pw->pw_name);
-
- /* Send a message indicating that the authentication attempt failed. */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
- }
-}
-
-/*
- * Performs authentication of an incoming connection. Session key has already
- * been exchanged and encryption is enabled.
- */
-void
-do_authentication()
-{
- struct passwd *pw, pwcopy;
- int plen;
- unsigned int ulen;
- char *user;
-
- /* Get the name of the user that we wish to log in as. */
- packet_read_expect(&plen, SSH_CMSG_USER);
-
- /* Get the user name. */
- user = packet_get_string(&ulen);
- packet_integrity_check(plen, (4 + ulen), SSH_CMSG_USER);
-
- setproctitle("%s", user);
-
-#ifdef AFS
- /* If machine has AFS, set process authentication group. */
- if (k_hasafs()) {
- k_setpag();
- k_unlog();
- }
-#endif /* AFS */
-
- /* Verify that the user is a valid user. */
- pw = getpwnam(user);
- if (!pw || !allowed_user(pw))
- do_fake_authloop1(user);
- xfree(user);
-
- /* Take a copy of the returned structure. */
- memset(&pwcopy, 0, sizeof(pwcopy));
- pwcopy.pw_name = xstrdup(pw->pw_name);
- pwcopy.pw_passwd = xstrdup(pw->pw_passwd);
- pwcopy.pw_uid = pw->pw_uid;
- pwcopy.pw_gid = pw->pw_gid;
- pwcopy.pw_dir = xstrdup(pw->pw_dir);
- pwcopy.pw_shell = xstrdup(pw->pw_shell);
- pwcopy.pw_class = xstrdup(pw->pw_class);
- pwcopy.pw_expire = pw->pw_expire;
- pwcopy.pw_change = pw->pw_change;
- pw = &pwcopy;
-
- /*
- * If we are not running as root, the user must have the same uid as
- * the server.
- */
- if (getuid() != 0 && pw->pw_uid != getuid())
- packet_disconnect("Cannot change user when server not running as root.");
-
- debug("Attempting authentication for %.100s.", pw->pw_name);
-
- /* If the user has no password, accept authentication immediately. */
- if (options.password_authentication &&
-#ifdef KRB5
- !options.krb5_authentication &&
-#endif /* KRB5 */
-#ifdef KRB4
- (!options.krb4_authentication || options.krb4_or_local_passwd) &&
-#endif /* KRB4 */
- auth_password(pw, "")) {
- /* Authentication with empty password succeeded. */
- log("Login for user %s from %.100s, accepted without authentication.",
- pw->pw_name, get_remote_ipaddr());
- } else {
- /* Loop until the user has been authenticated or the
- connection is closed, do_authloop() returns only if
- authentication is successfull */
- do_authloop(pw);
- }
-
- /* The user has been authenticated and accepted. */
- packet_start(SSH_SMSG_SUCCESS);
- packet_send();
- packet_write_wait();
-
- /* Perform session preparation. */
- do_authenticated(pw);
-}
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-03 00:31:10 +0000