--- /dev/null
+
+20060910
+ - [ gss-genr.c kexgssc.c kexgsss.c kex.h monitor.c sshconnect2.c sshd.c
+ ssh-gss.h ]
+ add support for gss-group14-sha1 key exchange mechanisms
+ - [ gss-serv.c servconf.c servconf.h sshd_config sshd_config.5 ]
+ Add GSSAPIStrictAcceptorCheck option to allow the disabling of
+ acceptor principal checking on multi-homed machines.
+ <Bugzilla #928>
+ - [ sshd_config ssh_config ]
+ Add settings for GSSAPIKeyExchange and GSSAPITrustDNS to the sample
+ configuration files
+ - [ kexgss.c kegsss.c sshconnect2.c sshd.c ]
+ Code cleanup. Replace strlen/xmalloc/snprintf sequences with xasprintf()
+ Limit length of error messages displayed by client
+
+20060909
+ - [ gss-genr.c gss-serv.c ]
+ move ssh_gssapi_acquire_cred() and ssh_gssapi_server_ctx to be server
+ only, where they belong
+ <Bugzilla #1225>
+
+20060829
+ - [ gss-serv-krb5.c ]
+ Fix CCAPI credentials cache name when creating KRB5CCNAME environment
+ variable
+
+20060828
+ - [ gss-genr.c ]
+ Avoid Heimdal context freeing problem
+ <Fixed upstream 20060829>
+
+20060818
+ - [ gss-genr.c ssh-gss.h sshconnect2.c ]
+ Make sure that SPENGO is disabled
+ <Bugzilla #1218 - Fixed upstream 20060818>
+
+20060421
+ - [ gssgenr.c, sshconnect2.c ]
+ a few type changes (signed versus unsigned, int versus size_t) to
+ fix compiler errors/warnings
+ (from jbasney AT ncsa.uiuc.edu)
+ - [ kexgssc.c, sshconnect2.c ]
+ fix uninitialized variable warnings
+ (from jbasney AT ncsa.uiuc.edu)
+ - [ gssgenr.c ]
+ pass oid to gss_display_status (helpful when using GSSAPI mechglue)
+ (from jbasney AT ncsa.uiuc.edu)
+ <Bugzilla #1220 >
+ - [ gss-serv-krb5.c ]
+ #ifdef HAVE_GSSAPI_KRB5 should be #ifdef HAVE_GSSAPI_KRB5_H
+ (from jbasney AT ncsa.uiuc.edu)
+ <Fixed upstream 20060304>
+ - [ readconf.c, readconf.h, ssh_config.5, sshconnect2.c
+ add client-side GssapiKeyExchange option
+ (from jbasney AT ncsa.uiuc.edu)
+ - [ sshconnect2.c ]
+ add support for GssapiTrustDns option for gssapi-with-mic
+ (from jbasney AT ncsa.uiuc.edu)
+ <gssapi-with-mic support is Bugzilla #1008>
atomicio.o key.o dispatch.o kex.o mac.o uidswap.o uuencode.o misc.o \
monitor_fdpass.o rijndael.o ssh-dss.o ssh-rsa.o dh.o kexdh.o \
kexgex.o kexdhc.o kexgexc.o scard.o msg.o progressmeter.o dns.o \
- entropy.o scard-opensc.o gss-genr.o
+ entropy.o scard-opensc.o gss-genr.o kexgssc.o
SSHOBJS= ssh.o readconf.o clientloop.o sshtty.o \
sshconnect.o sshconnect1.o sshconnect2.o
auth2-none.o auth2-passwd.o auth2-pubkey.o \
monitor_mm.o monitor.o monitor_wrap.o kexdhs.o kexgexs.o \
auth-krb5.o \
- auth2-gss.o gss-serv.o gss-serv-krb5.o \
+ auth2-gss.o gss-serv.o gss-serv-krb5.o kexgsss.o\
loginrec.o auth-pam.o auth-shadow.o auth-sia.o md5crypt.o \
audit.o audit-bsm.o platform.o
len = strlen(authctxt->krb5_ticket_file) + 6;
authctxt->krb5_ccname = xmalloc(len);
+#ifdef USE_CCAPI
+ snprintf(authctxt->krb5_ccname, len, "API:%s",
+ authctxt->krb5_ticket_file);
+#else
snprintf(authctxt->krb5_ccname, len, "FILE:%s",
authctxt->krb5_ticket_file);
+#endif
#ifdef USE_PAM
if (options.use_pam)
#ifndef HEIMDAL
krb5_error_code
ssh_krb5_cc_gen(krb5_context ctx, krb5_ccache *ccache) {
- int tmpfd, ret;
+ int ret;
char ccname[40];
mode_t old_umask;
+#ifdef USE_CCAPI
+ char cctemplate[] = "API:krb5cc_%d";
+#else
+ char cctemplate[] = "FILE:/tmp/krb5cc_%d_XXXXXXXXXX";
+ int tmpfd;
+#endif
ret = snprintf(ccname, sizeof(ccname),
- "FILE:/tmp/krb5cc_%d_XXXXXXXXXX", geteuid());
+ cctemplate, geteuid());
if (ret < 0 || (size_t)ret >= sizeof(ccname))
return ENOMEM;
+#ifndef USE_CCAPI
old_umask = umask(0177);
tmpfd = mkstemp(ccname + strlen("FILE:"));
umask(old_umask);
return errno;
}
close(tmpfd);
+#endif
return (krb5_cc_resolve(ctx, ccname, ccache));
}
int valid; /* user exists and is allowed to login */
int attempt;
int failures;
+ int server_caused_failure;
int force_pwchange;
char *user; /* username sent by the client */
char *service;
static void input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt);
static void input_gssapi_errtok(int, u_int32_t, void *);
+/*
+ * The 'gssapi_keyex' userauth mechanism.
+ */
+static int
+userauth_gsskeyex(Authctxt *authctxt)
+{
+ int authenticated = 0;
+ Buffer b;
+ gss_buffer_desc mic, gssbuf;
+ u_int len;
+
+ mic.value = packet_get_string(&len);
+ mic.length = len;
+
+ packet_check_eom();
+
+ ssh_gssapi_buildmic(&b, authctxt->user, authctxt->service,
+ "gssapi-keyex");
+
+ gssbuf.value = buffer_ptr(&b);
+ gssbuf.length = buffer_len(&b);
+
+ /* gss_kex_context is NULL with privsep, so we can't check it here */
+ if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gss_kex_context,
+ &gssbuf, &mic))))
+ authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
+
+ buffer_free(&b);
+ xfree(mic.value);
+
+ return (authenticated);
+}
+
/*
* We only support those mechanisms that we know about (ie ones that we know
* how to check local user kuserok and the like)
if (!present) {
xfree(doid);
+ authctxt->server_caused_failure = 1;
return (0);
}
if (ctxt != NULL)
ssh_gssapi_delete_ctx(&ctxt);
xfree(doid);
+ authctxt->server_caused_failure = 1;
return (0);
}
userauth_finish(authctxt, authenticated, "gssapi-with-mic");
}
+Authmethod method_gsskeyex = {
+ "gssapi-keyex",
+ userauth_gsskeyex,
+ &options.gss_authentication
+};
+
Authmethod method_gssapi = {
"gssapi-with-mic",
userauth_gssapi,
extern Authmethod method_kbdint;
extern Authmethod method_hostbased;
#ifdef GSSAPI
+extern Authmethod method_gsskeyex;
extern Authmethod method_gssapi;
#endif
&method_none,
&method_pubkey,
#ifdef GSSAPI
+ &method_gsskeyex,
&method_gssapi,
#endif
&method_passwd,
#endif
authctxt->postponed = 0;
+ authctxt->server_caused_failure = 0;
/* try to authenticate user */
m = authmethod_lookup(method);
/* now we can break out */
authctxt->success = 1;
} else {
- if (authctxt->failures++ > options.max_authtries) {
+ /* Dont count server configuration issues against the client */
+ if (!authctxt->server_caused_failure &&
+ authctxt->failures++ > options.max_authtries) {
#ifdef SSH_AUDIT_EVENTS
PRIVSEP(audit_event(SSH_LOGIN_EXCEED_MAXTRIES));
#endif
[Use tunnel device compatibility to OpenBSD])
AC_DEFINE(SSH_TUN_PREPEND_AF, 1,
[Prepend the address family to IP tunnel traffic])
- ;;
+ AC_MSG_CHECKING(if we have the Security Authorization Session API)
+ AC_TRY_COMPILE([#include <Security/AuthSession.h>],
+ [SessionCreate(0, 0);],
+ [ac_cv_use_security_session_api="yes"
+ AC_DEFINE(USE_SECURITY_SESSION_API, 1,
+ [platform has the Security Authorization Session API])
+ LIBS="$LIBS -framework Security"
+ AC_MSG_RESULT(yes)],
+ [ac_cv_use_security_session_api="no"
+ AC_MSG_RESULT(no)])
+ AC_MSG_CHECKING(if we have an in-memory credentials cache)
+ AC_TRY_COMPILE(
+ [#include <Kerberos/Kerberos.h>],
+ [cc_context_t c;
+ (void) cc_initialize (&c, 0, NULL, NULL);],
+ [AC_DEFINE(USE_CCAPI, 1,
+ [platform uses an in-memory credentials cache])
+ LIBS="$LIBS -framework Security"
+ AC_MSG_RESULT(yes)
+ if test "x$ac_cv_use_security_session_api" = "xno"; then
+ AC_MSG_ERROR(*** Need a security framework to use the credentials cache API ***)
+ fi],
+ [AC_MSG_RESULT(no)]
+ )
+ ;;
*-*-dragonfly*)
SSHDLIBS="$SSHDLIBS -lcrypt"
;;
#include "buffer.h"
#include "log.h"
#include "ssh2.h"
+#include "cipher.h"
+#include "key.h"
+#include "kex.h"
+#include <openssl/evp.h>
#include "ssh-gss.h"
extern u_char *session_id2;
extern u_int session_id2_len;
+typedef struct {
+ char *encoded;
+ gss_OID oid;
+} ssh_gss_kex_mapping;
+
+/*
+ * XXX - It would be nice to find a more elegant way of handling the
+ * XXX passing of the key exchange context to the userauth routines
+ */
+
+Gssctxt *gss_kex_context = NULL;
+
+static ssh_gss_kex_mapping *gss_enc2oid = NULL;
+
+int
+ssh_gssapi_oid_table_ok() {
+ return (gss_enc2oid != NULL);
+}
+
+/*
+ * Return a list of the gss-group1-sha1 mechanisms supported by this program
+ *
+ * We test mechanisms to ensure that we can use them, to avoid starting
+ * a key exchange with a bad mechanism
+ */
+
+char *
+ssh_gssapi_client_mechanisms(const char *host) {
+ gss_OID_set gss_supported;
+ OM_uint32 min_status;
+
+ gss_indicate_mechs(&min_status, &gss_supported);
+
+ return(ssh_gssapi_kex_mechs(gss_supported, ssh_gssapi_check_mechanism,
+ host));
+}
+
+char *
+ssh_gssapi_kex_mechs(gss_OID_set gss_supported, ssh_gssapi_check_fn *check,
+ const char *data) {
+ Buffer buf;
+ size_t i;
+ int oidpos, enclen;
+ char *mechs, *encoded;
+ u_char digest[EVP_MAX_MD_SIZE];
+ char deroid[2];
+ const EVP_MD *evp_md = EVP_md5();
+ EVP_MD_CTX md;
+
+ if (gss_enc2oid != NULL) {
+ for (i = 0; gss_enc2oid[i].encoded != NULL; i++)
+ xfree(gss_enc2oid[i].encoded);
+ xfree(gss_enc2oid);
+ }
+
+ gss_enc2oid = xmalloc(sizeof(ssh_gss_kex_mapping)*
+ (gss_supported->count + 1));
+
+ buffer_init(&buf);
+
+ oidpos = 0;
+ for (i = 0; i < gss_supported->count; i++) {
+ if (gss_supported->elements[i].length < 128 &&
+ (*check)(NULL, &(gss_supported->elements[i]), data)) {
+ deroid[0] = SSH_GSS_OIDTYPE;
+ deroid[1] = gss_supported->elements[i].length;
+
+ EVP_DigestInit(&md, evp_md);
+ EVP_DigestUpdate(&md, deroid, 2);
+ EVP_DigestUpdate(&md,
+ gss_supported->elements[i].elements,
+ gss_supported->elements[i].length);
+ EVP_DigestFinal(&md, digest, NULL);
+
+ encoded = xmalloc(EVP_MD_size(evp_md) * 2);
+ enclen = __b64_ntop(digest, EVP_MD_size(evp_md),
+ encoded, EVP_MD_size(evp_md) * 2);
+
+ if (oidpos != 0)
+ buffer_put_char(&buf, ',');
+
+ buffer_append(&buf, KEX_GSS_GEX_SHA1_ID,
+ sizeof(KEX_GSS_GEX_SHA1_ID) - 1);
+ buffer_append(&buf, encoded, enclen);
+ buffer_put_char(&buf, ',');
+ buffer_append(&buf, KEX_GSS_GRP1_SHA1_ID,
+ sizeof(KEX_GSS_GRP1_SHA1_ID) - 1);
+ buffer_append(&buf, encoded, enclen);
+ buffer_put_char(&buf, ',');
+ buffer_append(&buf, KEX_GSS_GRP14_SHA1_ID,
+ sizeof(KEX_GSS_GRP14_SHA1_ID) - 1);
+ buffer_append(&buf, encoded, enclen);
+
+ gss_enc2oid[oidpos].oid = &(gss_supported->elements[i]);
+ gss_enc2oid[oidpos].encoded = encoded;
+ oidpos++;
+ }
+ }
+ gss_enc2oid[oidpos].oid = NULL;
+ gss_enc2oid[oidpos].encoded = NULL;
+
+ buffer_put_char(&buf, '\0');
+
+ mechs = xmalloc(buffer_len(&buf));
+ buffer_get(&buf, mechs, buffer_len(&buf));
+ buffer_free(&buf);
+
+ if (strlen(mechs) == 0) {
+ xfree(mechs);
+ mechs = NULL;
+ }
+
+ return (mechs);
+}
+
+gss_OID
+ssh_gssapi_id_kex(Gssctxt *ctx, char *name, int kex_type) {
+ int i = 0;
+
+ switch (kex_type) {
+ case KEX_GSS_GRP1_SHA1:
+ name += sizeof(KEX_GSS_GRP1_SHA1_ID) - 1;
+ break;
+ case KEX_GSS_GRP14_SHA1:
+ name += sizeof(KEX_GSS_GRP14_SHA1_ID) - 1;
+ break;
+ case KEX_GSS_GEX_SHA1:
+ name += sizeof(KEX_GSS_GEX_SHA1_ID) - 1;
+ break;
+ default:
+ return GSS_C_NO_OID;
+ }
+
+ while (gss_enc2oid[i].encoded != NULL &&
+ strcmp(name, gss_enc2oid[i].encoded) != 0)
+ i++;
+
+ if (gss_enc2oid[i].oid != NULL && ctx != NULL)
+ ssh_gssapi_set_oid(ctx, gss_enc2oid[i].oid);
+
+ return gss_enc2oid[i].oid;
+}
+
/* Check that the OID in a data stream matches that in the context */
int
ssh_gssapi_check_oid(Gssctxt *ctx, void *data, size_t len)
/* The GSSAPI error */
do {
gss_display_status(&lmin, ctxt->major,
- GSS_C_GSS_CODE, GSS_C_NULL_OID, &ctx, &msg);
+ GSS_C_GSS_CODE, ctxt->oid, &ctx, &msg);
buffer_append(&b, msg.value, msg.length);
buffer_put_char(&b, '\n');
/* The mechanism specific error */
do {
gss_display_status(&lmin, ctxt->minor,
- GSS_C_MECH_CODE, GSS_C_NULL_OID, &ctx, &msg);
+ GSS_C_MECH_CODE, ctxt->oid, &ctx, &msg);
buffer_append(&b, msg.value, msg.length);
buffer_put_char(&b, '\n');
return (ctx->major);
}
-/* Acquire credentials for a server running on the current host.
- * Requires that the context structure contains a valid OID
- */
-
-/* Returns a GSSAPI error code */
OM_uint32
-ssh_gssapi_acquire_cred(Gssctxt *ctx)
+ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
{
- OM_uint32 status;
- char lname[MAXHOSTNAMELEN];
- gss_OID_set oidset;
-
- gss_create_empty_oid_set(&status, &oidset);
- gss_add_oid_set_member(&status, ctx->oid, &oidset);
-
- if (gethostname(lname, MAXHOSTNAMELEN)) {
- gss_release_oid_set(&status, &oidset);
- return (-1);
- }
+ if (ctx == NULL)
+ return -1;
- if (GSS_ERROR(ssh_gssapi_import_name(ctx, lname))) {
- gss_release_oid_set(&status, &oidset);
- return (ctx->major);
- }
-
- if ((ctx->major = gss_acquire_cred(&ctx->minor,
- ctx->name, 0, oidset, GSS_C_ACCEPT, &ctx->creds, NULL, NULL)))
+ if ((ctx->major = gss_get_mic(&ctx->minor, ctx->context,
+ GSS_C_QOP_DEFAULT, buffer, hash)))
ssh_gssapi_error(ctx);
- gss_release_oid_set(&status, &oidset);
return (ctx->major);
}
+/* Priviledged when used by server */
OM_uint32
-ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_t buffer, gss_buffer_t hash)
+ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
{
- if ((ctx->major = gss_get_mic(&ctx->minor, ctx->context,
- GSS_C_QOP_DEFAULT, buffer, hash)))
- ssh_gssapi_error(ctx);
+ if (ctx == NULL)
+ return -1;
+
+ ctx->major = gss_verify_mic(&ctx->minor, ctx->context,
+ gssbuf, gssmic, NULL);
return (ctx->major);
}
buffer_put_cstring(b, context);
}
-OM_uint32
-ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid)
-{
- if (*ctx)
- ssh_gssapi_delete_ctx(ctx);
- ssh_gssapi_build_ctx(ctx);
- ssh_gssapi_set_oid(*ctx, oid);
- return (ssh_gssapi_acquire_cred(*ctx));
-}
-
int
ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
{
gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
OM_uint32 major, minor;
gss_OID_desc spnego_oid = {6, (void *)"\x2B\x06\x01\x05\x05\x02"};
+ Gssctxt *intctx = NULL;
+
+ if (ctx == NULL)
+ ctx = &intctx;
/* RFC 4462 says we MUST NOT do SPNEGO */
if (oid->length == spnego_oid.length &&
GSS_C_NO_BUFFER);
}
- if (GSS_ERROR(major))
+ if (GSS_ERROR(major) || intctx != NULL)
ssh_gssapi_delete_ctx(ctx);
return (!GSS_ERROR(major));
return;
}
- client->store.filename = xstrdup(krb5_cc_get_name(krb_context, ccache));
+ const char* new_ccname = krb5_cc_get_name(krb_context, ccache);
+
client->store.envvar = "KRB5CCNAME";
- len = strlen(client->store.filename) + 6;
- client->store.envval = xmalloc(len);
- snprintf(client->store.envval, len, "FILE:%s", client->store.filename);
+#ifdef USE_CCAPI
+ xasprintf(&client->store.envval, "API:%s", new_ccname);
+ client->store.filename = NULL;
+#else
+ xasprintf(&client->store.envval, "FILE:%s", new_ccname);
+ client->store.filename = xstrdup(new_ccname);
+#endif
#ifdef USE_PAM
if (options.use_pam)
/* $OpenBSD: gss-serv.c,v 1.20 2006/08/03 03:34:42 deraadt Exp $ */
/*
- * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
+ * Copyright (c) 2001-2006 Simon Wilkinson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
#include "channels.h"
#include "session.h"
#include "misc.h"
+#include "servconf.h"
#include "ssh-gss.h"
+#include "monitor_wrap.h"
+
+extern ServerOptions options;
static ssh_gssapi_client gssapi_client =
{ GSS_C_EMPTY_BUFFER, GSS_C_EMPTY_BUFFER,
&gssapi_null_mech,
};
+/* Unprivileged */
+char *
+ssh_gssapi_server_mechanisms() {
+ gss_OID_set supported;
+
+ ssh_gssapi_supported_oids(&supported);
+ return (ssh_gssapi_kex_mechs(supported, &ssh_gssapi_server_check_mech,
+ NULL));
+}
+
+/* Unprivileged */
+int
+ssh_gssapi_server_check_mech(Gssctxt **dum, gss_OID oid, const char *data) {
+ Gssctxt *ctx = NULL;
+ int res;
+
+ res = !GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctx, oid)));
+ ssh_gssapi_delete_ctx(&ctx);
+
+ return (res);
+}
+
/* Unprivileged */
void
ssh_gssapi_supported_oids(gss_OID_set *oidset)
gss_release_oid_set(&min_status, &supported);
}
+OM_uint32
+ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid)
+{
+ if (*ctx)
+ ssh_gssapi_delete_ctx(ctx);
+ ssh_gssapi_build_ctx(ctx);
+ ssh_gssapi_set_oid(*ctx, oid);
+ return (ssh_gssapi_acquire_cred(*ctx));
+}
+
+/* Acquire credentials for a server running on the current host.
+ * Requires that the context structure contains a valid OID
+ */
+
+/* Returns a GSSAPI error code */
+OM_uint32
+ssh_gssapi_acquire_cred(Gssctxt *ctx)
+{
+ OM_uint32 status;
+ char lname[MAXHOSTNAMELEN];
+ gss_OID_set oidset;
+
+ if (options.gss_strict_acceptor) {
+ gss_create_empty_oid_set(&status, &oidset);
+ gss_add_oid_set_member(&status, ctx->oid, &oidset);
+
+ if (gethostname(lname, MAXHOSTNAMELEN)) {
+ gss_release_oid_set(&status, &oidset);
+ return (-1);
+ }
+
+ if (GSS_ERROR(ssh_gssapi_import_name(ctx, lname))) {
+ gss_release_oid_set(&status, &oidset);
+ return (ctx->major);
+ }
+
+ if ((ctx->major = gss_acquire_cred(&ctx->minor,
+ ctx->name, 0, oidset, GSS_C_ACCEPT, &ctx->creds,
+ NULL, NULL)))
+ ssh_gssapi_error(ctx);
+
+ gss_release_oid_set(&status, &oidset);
+ return (ctx->major);
+ } else {
+ ctx->name = GSS_C_NO_NAME;
+ ctx->creds = GSS_C_NO_CREDENTIAL;
+ }
+ return GSS_S_COMPLETE;
+}
+
/* Wrapper around accept_sec_context
* Requires that the context contains:
return (0);
}
-/* Privileged */
-OM_uint32
-ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
-{
- ctx->major = gss_verify_mic(&ctx->minor, ctx->context,
- gssbuf, gssmic, NULL);
-
- return (ctx->major);
-}
-
#endif
#include "dispatch.h"
#include "monitor.h"
+#ifdef GSSAPI
+#include "ssh-gss.h"
+#endif
+
#define KEX_COOKIE_LEN 16
#if OPENSSL_VERSION_NUMBER >= 0x00907000L
} else if (strcmp(k->name, KEX_DHGEX_SHA256) == 0) {
k->kex_type = KEX_DH_GEX_SHA256;
k->evp_md = evp_ssh_sha256();
+#endif
+#ifdef GSSAPI
+ } else if (strncmp(k->name, KEX_GSS_GEX_SHA1_ID,
+ sizeof(KEX_GSS_GEX_SHA1_ID) - 1) == 0) {
+ k->kex_type = KEX_GSS_GEX_SHA1;
+ k->evp_md = EVP_sha1();
+ } else if (strncmp(k->name, KEX_GSS_GRP1_SHA1_ID,
+ sizeof(KEX_GSS_GRP1_SHA1_ID) - 1) == 0) {
+ k->kex_type = KEX_GSS_GRP1_SHA1;
+ k->evp_md = EVP_sha1();
+ } else if (strncmp(k->name, KEX_GSS_GRP14_SHA1_ID,
+ sizeof(KEX_GSS_GRP14_SHA1_ID) - 1) == 0) {
+ k->kex_type = KEX_GSS_GRP14_SHA1;
+ k->evp_md = EVP_sha1();
#endif
} else
fatal("bad kex alg %s", k->name);
KEX_DH_GRP14_SHA1,
KEX_DH_GEX_SHA1,
KEX_DH_GEX_SHA256,
+ KEX_GSS_GRP1_SHA1,
+ KEX_GSS_GRP14_SHA1,
+ KEX_GSS_GEX_SHA1,
KEX_MAX
};
sig_atomic_t done;
int flags;
const EVP_MD *evp_md;
+#ifdef GSSAPI
+ int gss_deleg_creds;
+ int gss_trust_dns;
+ char *gss_host;
+#endif
char *client_version_string;
char *server_version_string;
int (*verify_host_key)(Key *);
void kexgex_client(Kex *);
void kexgex_server(Kex *);
+#ifdef GSSAPI
+void kexgss_client(Kex *);
+void kexgss_server(Kex *);
+#endif
+
void
kex_dh_hash(char *, char *, char *, int, char *, int, u_char *, int,
BIGNUM *, BIGNUM *, BIGNUM *, u_char **, u_int *);
--- /dev/null
+/*
+ * Copyright (c) 2001-2006 Simon Wilkinson. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#ifdef GSSAPI
+
+#include "includes.h"
+
+#include <openssl/crypto.h>
+#include <openssl/bn.h>
+
+#include <string.h>
+
+#include "xmalloc.h"
+#include "buffer.h"
+#include "ssh2.h"
+#include "key.h"
+#include "cipher.h"
+#include "kex.h"
+#include "log.h"
+#include "packet.h"
+#include "dh.h"
+
+#include "ssh-gss.h"
+
+void
+kexgss_client(Kex *kex) {
+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
+ gss_buffer_desc recv_tok, gssbuf, msg_tok, *token_ptr;
+ Gssctxt *ctxt;
+ OM_uint32 maj_status, min_status, ret_flags;
+ u_int klen, kout, slen = 0, hashlen, strlen;
+ DH *dh;
+ BIGNUM *dh_server_pub = NULL;
+ BIGNUM *shared_secret = NULL;
+ BIGNUM *p = NULL;
+ BIGNUM *g = NULL;
+ u_char *kbuf, *hash;
+ u_char *serverhostkey = NULL;
+ char *msg;
+ char *lang;
+ int type = 0;
+ int first = 1;
+ int nbits = 0, min = DH_GRP_MIN, max = DH_GRP_MAX;
+
+ /* Initialise our GSSAPI world */
+ ssh_gssapi_build_ctx(&ctxt);
+ if (ssh_gssapi_id_kex(ctxt, kex->name, kex->kex_type)
+ == GSS_C_NO_OID)
+ fatal("Couldn't identify host exchange");
+
+ if (ssh_gssapi_import_name(ctxt, kex->gss_host))
+ fatal("Couldn't import hostname");
+
+ switch (kex->kex_type) {
+ case KEX_GSS_GRP1_SHA1:
+ dh = dh_new_group1();
+ break;
+ case KEX_GSS_GRP14_SHA1:
+ dh = dh_new_group14();
+ break;
+ case KEX_GSS_GEX_SHA1:
+ debug("Doing group exchange\n");
+ nbits = dh_estimate(kex->we_need * 8);
+ packet_start(SSH2_MSG_KEXGSS_GROUPREQ);
+ packet_put_int(min);
+ packet_put_int(nbits);
+ packet_put_int(max);
+
+ packet_send();
+
+ packet_read_expect(SSH2_MSG_KEXGSS_GROUP);
+
+ if ((p = BN_new()) == NULL)
+ fatal("BN_new() failed");
+ packet_get_bignum2(p);
+ if ((g = BN_new()) == NULL)
+ fatal("BN_new() failed");
+ packet_get_bignum2(g);
+ packet_check_eom();
+
+ if (BN_num_bits(p) < min || BN_num_bits(p) > max)
+ fatal("GSSGRP_GEX group out of range: %d !< %d !< %d",
+ min, BN_num_bits(p), max);
+
+ dh = dh_new_group(g, p);
+ break;
+ default:
+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+ }
+
+ /* Step 1 - e is dh->pub_key */
+ dh_gen_key(dh, kex->we_need * 8);
+
+ /* This is f, we initialise it now to make life easier */
+ dh_server_pub = BN_new();
+ if (dh_server_pub == NULL)
+ fatal("dh_server_pub == NULL");
+
+ token_ptr = GSS_C_NO_BUFFER;
+
+ do {
+ debug("Calling gss_init_sec_context");
+
+ maj_status = ssh_gssapi_init_ctx(ctxt,
+ kex->gss_deleg_creds, token_ptr, &send_tok,
+ &ret_flags);
+
+ if (GSS_ERROR(maj_status)) {
+ if (send_tok.length != 0) {
+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
+ packet_put_string(send_tok.value,
+ send_tok.length);
+ }
+ fatal("gss_init_context failed");
+ }
+
+ /* If we've got an old receive buffer get rid of it */
+ if (token_ptr != GSS_C_NO_BUFFER)
+ xfree(recv_tok.value);
+
+ if (maj_status == GSS_S_COMPLETE) {
+ /* If mutual state flag is not true, kex fails */
+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
+ fatal("Mutual authentication failed");
+
+ /* If integ avail flag is not true kex fails */
+ if (!(ret_flags & GSS_C_INTEG_FLAG))
+ fatal("Integrity check failed");
+ }
+
+ /*
+ * If we have data to send, then the last message that we
+ * received cannot have been a 'complete'.
+ */
+ if (send_tok.length != 0) {
+ if (first) {
+ packet_start(SSH2_MSG_KEXGSS_INIT);
+ packet_put_string(send_tok.value,
+ send_tok.length);
+ packet_put_bignum2(dh->pub_key);
+ first = 0;
+ } else {
+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
+ packet_put_string(send_tok.value,
+ send_tok.length);
+ }
+ packet_send();
+ gss_release_buffer(&min_status, &send_tok);
+
+ /* If we've sent them data, they should reply */
+ do {
+ type = packet_read();
+ if (type == SSH2_MSG_KEXGSS_HOSTKEY) {
+ debug("Received KEXGSS_HOSTKEY");
+ if (serverhostkey)
+ fatal("Server host key received more than once");
+ serverhostkey =
+ packet_get_string(&slen);
+ }
+ } while (type == SSH2_MSG_KEXGSS_HOSTKEY);
+
+ switch (type) {
+ case SSH2_MSG_KEXGSS_CONTINUE:
+ debug("Received GSSAPI_CONTINUE");
+ if (maj_status == GSS_S_COMPLETE)
+ fatal("GSSAPI Continue received from server when complete");
+ recv_tok.value = packet_get_string(&strlen);
+ recv_tok.length = strlen;
+ break;
+ case SSH2_MSG_KEXGSS_COMPLETE:
+ debug("Received GSSAPI_COMPLETE");
+ packet_get_bignum2(dh_server_pub);
+ msg_tok.value = packet_get_string(&strlen);
+ msg_tok.length = strlen;
+
+ /* Is there a token included? */
+ if (packet_get_char()) {
+ recv_tok.value=
+ packet_get_string(&strlen);
+ recv_tok.length = strlen;
+ /* If we're already complete - protocol error */
+ if (maj_status == GSS_S_COMPLETE)
+ packet_disconnect("Protocol error: received token when complete");
+ } else {
+ /* No token included */
+ if (maj_status != GSS_S_COMPLETE)
+ packet_disconnect("Protocol error: did not receive final token");
+ }
+ break;
+ case SSH2_MSG_KEXGSS_ERROR:
+ debug("Received Error");
+ maj_status = packet_get_int();
+ min_status = packet_get_int();
+ msg = packet_get_string(NULL);
+ lang = packet_get_string(NULL);
+ fatal("GSSAPI Error: \n%.400s",msg);
+ default:
+ packet_disconnect("Protocol error: didn't expect packet type %d",
+ type);
+ }
+ token_ptr = &recv_tok;
+ } else {
+ /* No data, and not complete */
+ if (maj_status != GSS_S_COMPLETE)
+ fatal("Not complete, and no token output");
+ }
+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
+
+ /*
+ * We _must_ have received a COMPLETE message in reply from the
+ * server, which will have set dh_server_pub and msg_tok
+ */
+
+ if (type != SSH2_MSG_KEXGSS_COMPLETE)
+ fatal("Didn't receive a SSH2_MSG_KEXGSS_COMPLETE when I expected it");
+
+ /* Check f in range [1, p-1] */
+ if (!dh_pub_is_valid(dh, dh_server_pub))
+ packet_disconnect("bad server public DH value");
+
+ /* compute K=f^x mod p */
+ klen = DH_size(dh);
+ kbuf = xmalloc(klen);
+ kout = DH_compute_key(kbuf, dh_server_pub, dh);
+
+ shared_secret = BN_new();
+ BN_bin2bn(kbuf,kout, shared_secret);
+ memset(kbuf, 0, klen);
+ xfree(kbuf);
+
+ switch (kex->kex_type) {
+ case KEX_GSS_GRP1_SHA1:
+ case KEX_GSS_GRP14_SHA1:
+ kex_dh_hash( kex->client_version_string,
+ kex->server_version_string,
+ buffer_ptr(&kex->my), buffer_len(&kex->my),
+ buffer_ptr(&kex->peer), buffer_len(&kex->peer),
+ serverhostkey, slen, /* server host key */
+ dh->pub_key, /* e */
+ dh_server_pub, /* f */
+ shared_secret, /* K */
+ &hash, &hashlen
+ );
+ break;
+ case KEX_GSS_GEX_SHA1:
+ kexgex_hash(
+ kex->evp_md,
+ kex->client_version_string,
+ kex->server_version_string,
+ buffer_ptr(&kex->my), buffer_len(&kex->my),
+ buffer_ptr(&kex->peer), buffer_len(&kex->peer),
+ serverhostkey, slen,
+ min, nbits, max,
+ dh->p, dh->g,
+ dh->pub_key,
+ dh_server_pub,
+ shared_secret,
+ &hash, &hashlen
+ );
+ break;
+ default:
+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+ }
+
+ gssbuf.value = hash;
+ gssbuf.length = hashlen;
+
+ /* Verify that the hash matches the MIC we just got. */
+ if (GSS_ERROR(ssh_gssapi_checkmic(ctxt, &gssbuf, &msg_tok)))
+ packet_disconnect("Hash's MIC didn't verify");
+
+ xfree(msg_tok.value);
+
+ DH_free(dh);
+ if (serverhostkey)
+ xfree(serverhostkey);
+ BN_clear_free(dh_server_pub);
+
+ /* save session id */
+ if (kex->session_id == NULL) {
+ kex->session_id_len = hashlen;
+ kex->session_id = xmalloc(kex->session_id_len);
+ memcpy(kex->session_id, hash, kex->session_id_len);
+ }
+
+ if (gss_kex_context == NULL)
+ gss_kex_context = ctxt;
+ else
+ ssh_gssapi_delete_ctx(&ctxt);
+
+ kex_derive_keys(kex, hash, hashlen, shared_secret);
+ BN_clear_free(shared_secret);
+ kex_finish(kex);
+}
+
+#endif /* GSSAPI */
--- /dev/null
+/*
+ * Copyright (c) 2001-2006 Simon Wilkinson. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#ifdef GSSAPI
+
+#include <string.h>
+
+#include <openssl/crypto.h>
+#include <openssl/bn.h>
+
+#include "xmalloc.h"
+#include "buffer.h"
+#include "ssh2.h"
+#include "key.h"
+#include "cipher.h"
+#include "kex.h"
+#include "log.h"
+#include "packet.h"
+#include "dh.h"
+#include "ssh-gss.h"
+#include "monitor_wrap.h"
+
+void
+kexgss_server(Kex *kex)
+{
+ OM_uint32 maj_status, min_status;
+
+ /*
+ * Some GSSAPI implementations use the input value of ret_flags (an
+ * output variable) as a means of triggering mechanism specific
+ * features. Initializing it to zero avoids inadvertently
+ * activating this non-standard behaviour.
+ */
+
+ OM_uint32 ret_flags = 0;
+ gss_buffer_desc gssbuf, recv_tok, msg_tok;
+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
+ Gssctxt *ctxt = NULL;
+ u_int slen, klen, kout, hashlen;
+ u_char *kbuf, *hash;
+ DH *dh;
+ int min = -1, max = -1, nbits = -1;
+ BIGNUM *shared_secret = NULL;
+ BIGNUM *dh_client_pub = NULL;
+ int type = 0;
+ gss_OID oid;
+
+ /* Initialise GSSAPI */
+
+ /* If we're rekeying, privsep means that some of the private structures
+ * in the GSSAPI code are no longer available. This kludges them back
+ * into life
+ */
+ if (!ssh_gssapi_oid_table_ok())
+ ssh_gssapi_server_mechanisms();
+
+ debug2("%s: Identifying %s", __func__, kex->name);
+ oid = ssh_gssapi_id_kex(NULL, kex->name, kex->kex_type);
+ if (oid == GSS_C_NO_OID)
+ fatal("Unknown gssapi mechanism");
+
+ debug2("%s: Acquiring credentials", __func__);
+
+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctxt, oid))))
+ fatal("Unable to acquire credentials for the server");
+
+ switch (kex->kex_type) {
+ case KEX_GSS_GRP1_SHA1:
+ dh = dh_new_group1();
+ break;
+ case KEX_GSS_GRP14_SHA1:
+ dh = dh_new_group14();
+ break;
+ case KEX_GSS_GEX_SHA1:
+ debug("Doing group exchange");
+ packet_read_expect(SSH2_MSG_KEXGSS_GROUPREQ);
+ min = packet_get_int();
+ nbits = packet_get_int();
+ max = packet_get_int();
+ min = MAX(DH_GRP_MIN, min);
+ max = MIN(DH_GRP_MAX, max);
+ packet_check_eom();
+ if (max < min || nbits < min || max < nbits)
+ fatal("GSS_GEX, bad parameters: %d !< %d !< %d",
+ min, nbits, max);
+ dh = PRIVSEP(choose_dh(min, nbits, max));
+ if (dh == NULL)
+ packet_disconnect("Protocol error: no matching group found");
+
+ packet_start(SSH2_MSG_KEXGSS_GROUP);
+ packet_put_bignum2(dh->p);
+ packet_put_bignum2(dh->g);
+ packet_send();
+
+ packet_write_wait();
+ break;
+ default:
+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+ }
+
+ dh_gen_key(dh, kex->we_need * 8);
+
+ do {
+ debug("Wait SSH2_MSG_GSSAPI_INIT");
+ type = packet_read();
+ switch(type) {
+ case SSH2_MSG_KEXGSS_INIT:
+ if (dh_client_pub != NULL)
+ fatal("Received KEXGSS_INIT after initialising");
+ recv_tok.value = packet_get_string(&slen);
+ recv_tok.length = slen;
+
+ if ((dh_client_pub = BN_new()) == NULL)
+ fatal("dh_client_pub == NULL");
+
+ packet_get_bignum2(dh_client_pub);
+
+ /* Send SSH_MSG_KEXGSS_HOSTKEY here, if we want */
+ break;
+ case SSH2_MSG_KEXGSS_CONTINUE:
+ recv_tok.value = packet_get_string(&slen);
+ recv_tok.length = slen;
+ break;
+ default:
+ packet_disconnect(
+ "Protocol error: didn't expect packet type %d",
+ type);
+ }
+
+ maj_status = PRIVSEP(ssh_gssapi_accept_ctx(ctxt, &recv_tok,
+ &send_tok, &ret_flags));
+
+ xfree(recv_tok.value);
+
+ if (maj_status != GSS_S_COMPLETE && send_tok.length == 0)
+ fatal("Zero length token output when incomplete");
+
+ if (dh_client_pub == NULL)
+ fatal("No client public key");
+
+ if (maj_status & GSS_S_CONTINUE_NEEDED) {
+ debug("Sending GSSAPI_CONTINUE");
+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
+ packet_put_string(send_tok.value, send_tok.length);
+ packet_send();
+ gss_release_buffer(&min_status, &send_tok);
+ }
+ } while (maj_status & GSS_S_CONTINUE_NEEDED);
+
+ if (GSS_ERROR(maj_status)) {
+ if (send_tok.length > 0) {
+ packet_start(SSH2_MSG_KEXGSS_CONTINUE);
+ packet_put_string(send_tok.value, send_tok.length);
+ packet_send();
+ }
+ fatal("accept_ctx died");
+ }
+
+ if (!(ret_flags & GSS_C_MUTUAL_FLAG))
+ fatal("Mutual Authentication flag wasn't set");
+
+ if (!(ret_flags & GSS_C_INTEG_FLAG))
+ fatal("Integrity flag wasn't set");
+
+ if (!dh_pub_is_valid(dh, dh_client_pub))
+ packet_disconnect("bad client public DH value");
+
+ klen = DH_size(dh);
+ kbuf = xmalloc(klen);
+ kout = DH_compute_key(kbuf, dh_client_pub, dh);
+
+ shared_secret = BN_new();
+ BN_bin2bn(kbuf, kout, shared_secret);
+ memset(kbuf, 0, klen);
+ xfree(kbuf);
+
+ switch (kex->kex_type) {
+ case KEX_GSS_GRP1_SHA1:
+ case KEX_GSS_GRP14_SHA1:
+ kex_dh_hash(
+ kex->client_version_string, kex->server_version_string,
+ buffer_ptr(&kex->peer), buffer_len(&kex->peer),
+ buffer_ptr(&kex->my), buffer_len(&kex->my),
+ NULL, 0, /* Change this if we start sending host keys */
+ dh_client_pub, dh->pub_key, shared_secret,
+ &hash, &hashlen
+ );
+ break;
+ case KEX_GSS_GEX_SHA1:
+ kexgex_hash(
+ kex->evp_md,
+ kex->client_version_string, kex->server_version_string,
+ buffer_ptr(&kex->peer), buffer_len(&kex->peer),
+ buffer_ptr(&kex->my), buffer_len(&kex->my),
+ NULL, 0,
+ min, nbits, max,
+ dh->p, dh->g,
+ dh_client_pub,
+ dh->pub_key,
+ shared_secret,
+ &hash, &hashlen
+ );
+ break;
+ default:
+ fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+ }
+
+ BN_free(dh_client_pub);
+
+ if (kex->session_id == NULL) {
+ kex->session_id_len = hashlen;
+ kex->session_id = xmalloc(kex->session_id_len);
+ memcpy(kex->session_id, hash, kex->session_id_len);
+ }
+
+ gssbuf.value = hash;
+ gssbuf.length = hashlen;
+
+ if (GSS_ERROR(PRIVSEP(ssh_gssapi_sign(ctxt,&gssbuf,&msg_tok))))
+ fatal("Couldn't get MIC");
+
+ packet_start(SSH2_MSG_KEXGSS_COMPLETE);
+ packet_put_bignum2(dh->pub_key);
+ packet_put_string(msg_tok.value,msg_tok.length);
+
+ if (send_tok.length != 0) {
+ packet_put_char(1); /* true */
+ packet_put_string(send_tok.value, send_tok.length);
+ } else {
+ packet_put_char(0); /* false */
+ }
+ packet_send();
+
+ gss_release_buffer(&min_status, &send_tok);
+ gss_release_buffer(&min_status, &msg_tok);
+
+ if (gss_kex_context == NULL)
+ gss_kex_context = ctxt;
+ else
+ ssh_gssapi_delete_ctx(&ctxt);
+
+ DH_free(dh);
+
+ kex_derive_keys(kex, hash, hashlen, shared_secret);
+ BN_clear_free(shared_secret);
+ kex_finish(kex);
+}
+#endif /* GSSAPI */
return KEY_RSA;
} else if (strcmp(name, "ssh-dss") == 0) {
return KEY_DSA;
+ } else if (strcmp(name, "null") == 0) {
+ return KEY_NULL;
}
debug2("key_type_from_name: unknown key type '%s'", name);
return KEY_UNSPEC;
KEY_RSA1,
KEY_RSA,
KEY_DSA,
+ KEY_NULL,
KEY_UNSPEC
};
enum fp_type {
int mm_answer_gss_accept_ctx(int, Buffer *);
int mm_answer_gss_userok(int, Buffer *);
int mm_answer_gss_checkmic(int, Buffer *);
+int mm_answer_gss_sign(int, Buffer *);
#endif
#ifdef SSH_AUDIT_EVENTS
{MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
{MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
{MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
+ {MONITOR_REQ_GSSSIGN, MON_ONCE, mm_answer_gss_sign},
#endif
{0, 0, NULL}
};
struct mon_table mon_dispatch_postauth20[] = {
+#ifdef GSSAPI
+ {MONITOR_REQ_GSSSETUP, 0, mm_answer_gss_setup_ctx},
+ {MONITOR_REQ_GSSSTEP, 0, mm_answer_gss_accept_ctx},
+ {MONITOR_REQ_GSSSIGN, 0, mm_answer_gss_sign},
+#endif
{MONITOR_REQ_MODULI, 0, mm_answer_moduli},
{MONITOR_REQ_SIGN, 0, mm_answer_sign},
{MONITOR_REQ_PTY, 0, mm_answer_pty},
/* Permit requests for moduli and signatures */
monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
+#ifdef GSSAPI
+ /* and for the GSSAPI key exchange */
+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSETUP, 1);
+#endif
} else {
mon_dispatch = mon_dispatch_proto15;
monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
+#ifdef GSSAPI
+ /* and for the GSSAPI key exchange */
+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSETUP, 1);
+#endif
} else {
mon_dispatch = mon_dispatch_postauth15;
monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
+#ifdef GSSAPI
+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server;
+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_server;
+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_server;
+#endif
kex->server = 1;
kex->hostkey_type = buffer_get_int(m);
kex->kex_type = buffer_get_int(m);
monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
+ monitor_permit(mon_dispatch, MONITOR_REQ_GSSSIGN, 1);
}
return (0);
}
/* Monitor loop will terminate if authenticated */
return (authenticated);
}
+
+int
+mm_answer_gss_sign(int socket, Buffer *m)
+{
+ gss_buffer_desc data;
+ gss_buffer_desc hash = GSS_C_EMPTY_BUFFER;
+ OM_uint32 major, minor;
+ u_int len;
+
+ data.value = buffer_get_string(m, &len);
+ data.length = len;
+ if (data.length != 20)
+ fatal("%s: data length incorrect: %d", __func__, data.length);
+
+ /* Save the session ID on the first time around */
+ if (session_id2_len == 0) {
+ session_id2_len = data.length;
+ session_id2 = xmalloc(session_id2_len);
+ memcpy(session_id2, data.value, session_id2_len);
+ }
+ major = ssh_gssapi_sign(gsscontext, &data, &hash);
+
+ xfree(data.value);
+
+ buffer_clear(m);
+ buffer_put_int(m, major);
+ buffer_put_string(m, hash.value, hash.length);
+
+ mm_request_send(socket, MONITOR_ANS_GSSSIGN, m);
+
+ gss_release_buffer(&minor, &hash);
+
+ /* Turn on getpwnam permissions */
+ monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
+
+ return (0);
+}
+
#endif /* GSSAPI */
MONITOR_REQ_GSSSTEP, MONITOR_ANS_GSSSTEP,
MONITOR_REQ_GSSUSEROK, MONITOR_ANS_GSSUSEROK,
MONITOR_REQ_GSSCHECKMIC, MONITOR_ANS_GSSCHECKMIC,
+ MONITOR_REQ_GSSSIGN, MONITOR_ANS_GSSSIGN,
MONITOR_REQ_PAM_START,
MONITOR_REQ_PAM_ACCOUNT, MONITOR_ANS_PAM_ACCOUNT,
MONITOR_REQ_PAM_INIT_CTX, MONITOR_ANS_PAM_INIT_CTX,
debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
return (authenticated);
}
+
+OM_uint32
+mm_ssh_gssapi_sign(Gssctxt *ctx, gss_buffer_desc *data, gss_buffer_desc *hash)
+{
+ Buffer m;
+ OM_uint32 major;
+ u_int len;
+
+ buffer_init(&m);
+ buffer_put_string(&m, data->value, data->length);
+
+ mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSIGN, &m);
+ mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSIGN, &m);
+
+ major = buffer_get_int(&m);
+ hash->value = buffer_get_string(&m, &len);
+ hash->length = len;
+
+ buffer_free(&m);
+
+ return(major);
+}
+
#endif /* GSSAPI */
gss_buffer_desc *, gss_buffer_desc *, OM_uint32 *);
int mm_ssh_gssapi_userok(char *user);
OM_uint32 mm_ssh_gssapi_checkmic(Gssctxt *, gss_buffer_t, gss_buffer_t);
+OM_uint32 mm_ssh_gssapi_sign(Gssctxt *, gss_buffer_t, gss_buffer_t);
#endif
#ifdef USE_PAM
oClearAllForwardings, oNoHostAuthenticationForLocalhost,
oEnableSSHKeysign, oRekeyLimit, oVerifyHostKeyDNS, oConnectTimeout,
oAddressFamily, oGssAuthentication, oGssDelegateCreds,
+ oGssKeyEx,
+ oGssTrustDns,
oServerAliveInterval, oServerAliveCountMax, oIdentitiesOnly,
oSendEnv, oControlPath, oControlMaster, oHashKnownHosts,
oTunnel, oTunnelDevice, oLocalCommand, oPermitLocalCommand,
{ "afstokenpassing", oUnsupported },
#if defined(GSSAPI)
{ "gssapiauthentication", oGssAuthentication },
+ { "gssapikeyexchange", oGssKeyEx },
{ "gssapidelegatecredentials", oGssDelegateCreds },
+ { "gssapitrustdns", oGssTrustDns },
#else
{ "gssapiauthentication", oUnsupported },
+ { "gssapikeyexchange", oUnsupported },
{ "gssapidelegatecredentials", oUnsupported },
+ { "gssapitrustdns", oUnsupported },
#endif
{ "fallbacktorsh", oDeprecated },
{ "usersh", oDeprecated },
intptr = &options->gss_authentication;
goto parse_flag;
+ case oGssKeyEx:
+ intptr = &options->gss_keyex;
+ goto parse_flag;
+
case oGssDelegateCreds:
intptr = &options->gss_deleg_creds;
goto parse_flag;
+ case oGssTrustDns:
+ intptr = &options->gss_trust_dns;
+ goto parse_flag;
+
case oBatchMode:
intptr = &options->batch_mode;
goto parse_flag;
options->pubkey_authentication = -1;
options->challenge_response_authentication = -1;
options->gss_authentication = -1;
+ options->gss_keyex = -1;
options->gss_deleg_creds = -1;
+ options->gss_trust_dns = -1;
options->password_authentication = -1;
options->kbd_interactive_authentication = -1;
options->kbd_interactive_devices = NULL;
options->challenge_response_authentication = 1;
if (options->gss_authentication == -1)
options->gss_authentication = 0;
+ if (options->gss_keyex == -1)
+ options->gss_keyex = 0;
if (options->gss_deleg_creds == -1)
options->gss_deleg_creds = 0;
+ if (options->gss_trust_dns == -1)
+ options->gss_trust_dns = 0;
if (options->password_authentication == -1)
options->password_authentication = 1;
if (options->kbd_interactive_authentication == -1)
int challenge_response_authentication;
/* Try S/Key or TIS, authentication. */
int gss_authentication; /* Try GSS authentication */
+ int gss_keyex; /* Try GSS key exchange */
int gss_deleg_creds; /* Delegate GSS credentials */
+ int gss_trust_dns; /* Trust DNS for GSS canonicalization */
int password_authentication; /* Try password
* authentication. */
int kbd_interactive_authentication; /* Try keyboard-interactive auth. */
options->kerberos_ticket_cleanup = -1;
options->kerberos_get_afs_token = -1;
options->gss_authentication=-1;
+ options->gss_keyex = -1;
options->gss_cleanup_creds = -1;
+ options->gss_strict_acceptor = -1;
options->password_authentication = -1;
options->kbd_interactive_authentication = -1;
options->challenge_response_authentication = -1;
options->kerberos_get_afs_token = 0;
if (options->gss_authentication == -1)
options->gss_authentication = 0;
+ if (options->gss_keyex == -1)
+ options->gss_keyex = 0;
if (options->gss_cleanup_creds == -1)
options->gss_cleanup_creds = 1;
+ if (options->gss_strict_acceptor == -1)
+ options->gss_strict_acceptor = 0;
if (options->password_authentication == -1)
options->password_authentication = 1;
if (options->kbd_interactive_authentication == -1)
sBanner, sUseDNS, sHostbasedAuthentication,
sHostbasedUsesNameFromPacketOnly, sClientAliveInterval,
sClientAliveCountMax, sAuthorizedKeysFile, sAuthorizedKeysFile2,
- sGssAuthentication, sGssCleanupCreds, sAcceptEnv, sPermitTunnel,
+ sGssAuthentication, sGssCleanupCreds, sGssStrictAcceptor,
+ sGssKeyEx,
+ sAcceptEnv, sPermitTunnel,
sMatch, sPermitOpen, sForceCommand,
sUsePrivilegeSeparation,
sDeprecated, sUnsupported
#ifdef GSSAPI
{ "gssapiauthentication", sGssAuthentication, SSHCFG_GLOBAL },
{ "gssapicleanupcredentials", sGssCleanupCreds, SSHCFG_GLOBAL },
+ { "gssapistrictacceptorcheck", sGssStrictAcceptor, SSHCFG_GLOBAL },
+ { "gssapikeyexchange", sGssKeyEx, SSHCFG_GLOBAL },
#else
{ "gssapiauthentication", sUnsupported, SSHCFG_GLOBAL },
{ "gssapicleanupcredentials", sUnsupported, SSHCFG_GLOBAL },
+ { "gssapistrictacceptorcheck", sUnsupported, SSHCFG_GLOBAL },
+ { "gssapikeyexchange", sUnsupported, SSHCFG_GLOBAL },
#endif
{ "passwordauthentication", sPasswordAuthentication, SSHCFG_GLOBAL },
{ "kbdinteractiveauthentication", sKbdInteractiveAuthentication, SSHCFG_GLOBAL },
intptr = &options->gss_authentication;
goto parse_flag;
+ case sGssKeyEx:
+ intptr = &options->gss_keyex;
+ goto parse_flag;
+
case sGssCleanupCreds:
intptr = &options->gss_cleanup_creds;
goto parse_flag;
+ case sGssStrictAcceptor:
+ intptr = &options->gss_strict_acceptor;
+ goto parse_flag;
+
case sPasswordAuthentication:
intptr = &options->password_authentication;
goto parse_flag;
int kerberos_get_afs_token; /* If true, try to get AFS token if
* authenticated with Kerberos. */
int gss_authentication; /* If true, permit GSSAPI authentication */
+ int gss_keyex; /* If true, permit GSSAPI key exchange */
int gss_cleanup_creds; /* If true, destroy cred cache on logout */
+ int gss_strict_acceptor; /* If true, restrict the GSSAPI acceptor name */
int password_authentication; /* If true, permit password
* authentication. */
int kbd_interactive_authentication; /* If true, permit */
#define SSH_GSS_OIDTYPE 0x06
+#define SSH2_MSG_KEXGSS_INIT 30
+#define SSH2_MSG_KEXGSS_CONTINUE 31
+#define SSH2_MSG_KEXGSS_COMPLETE 32
+#define SSH2_MSG_KEXGSS_HOSTKEY 33
+#define SSH2_MSG_KEXGSS_ERROR 34
+#define SSH2_MSG_KEXGSS_GROUPREQ 40
+#define SSH2_MSG_KEXGSS_GROUP 41
+#define KEX_GSS_GRP1_SHA1_ID "gss-group1-sha1-"
+#define KEX_GSS_GRP14_SHA1_ID "gss-group14-sha1-"
+#define KEX_GSS_GEX_SHA1_ID "gss-gex-sha1-"
+
typedef struct {
char *filename;
char *envvar;
} Gssctxt;
extern ssh_gssapi_mech *supported_mechs[];
+extern Gssctxt *gss_kex_context;
int ssh_gssapi_check_oid(Gssctxt *, void *, size_t);
void ssh_gssapi_set_oid_data(Gssctxt *, void *, size_t);
int ssh_gssapi_check_mechanism(Gssctxt **, gss_OID, const char *);
/* In the server */
+typedef int ssh_gssapi_check_fn(Gssctxt **, gss_OID, const char *);
+char *ssh_gssapi_client_mechanisms(const char *host);
+char *ssh_gssapi_kex_mechs(gss_OID_set, ssh_gssapi_check_fn *, const char *);
+gss_OID ssh_gssapi_id_kex(Gssctxt *, char *, int);
+int ssh_gssapi_server_check_mech(Gssctxt **,gss_OID, const char *);
int ssh_gssapi_userok(char *name);
OM_uint32 ssh_gssapi_checkmic(Gssctxt *, gss_buffer_t, gss_buffer_t);
void ssh_gssapi_do_child(char ***, u_int *);
void ssh_gssapi_cleanup_creds(void);
void ssh_gssapi_storecreds(void);
+char *ssh_gssapi_server_mechanisms(void);
+int ssh_gssapi_oid_table_ok();
#endif /* GSSAPI */
#endif /* _SSH_GSS_H */
# HostbasedAuthentication no
# GSSAPIAuthentication no
# GSSAPIDelegateCredentials no
+# GSSAPIKeyExchange no
+# GSSAPITrustDNS no
# BatchMode no
# CheckHostIP yes
# AddressFamily any
The default is
.Dq no .
Note that this option applies to protocol version 2 only.
+.It Cm GSSAPIKeyExchange
+Specifies whether key exchange based on GSSAPI may be used. When using
+GSSAPI key exchange the server need not have a host key.
+The default is
+.Dq no .
+Note that this option applies to protocol version 2 only.
.It Cm GSSAPIDelegateCredentials
Forward (delegate) credentials to the server.
The default is
.Dq no .
Note that this option applies to protocol version 2 only.
+.It Cm GSSAPITrustDns
+Set to
+.Dq yes
+to indicate that the DNS is trusted to securely canonicalize
+the name of the host being connected to. If
+.Dq no ,
+the hostname entered on the
+command line will be passed untouched to the GSSAPI library.
+The default is
+.Dq no .
+This option only applies to protocol version 2 connections using GSSAPI.
.It Cm HashKnownHosts
Indicates that
.Xr ssh 1
{
Kex *kex;
+#ifdef GSSAPI
+ char *orig = NULL, *gss = NULL;
+ char *gss_host = NULL;
+#endif
+
xxx_host = host;
xxx_hostaddr = hostaddr;
+#ifdef GSSAPI
+ if (options.gss_keyex) {
+ /* Add the GSSAPI mechanisms currently supported on this
+ * client to the key exchange algorithm proposal */
+ orig = myproposal[PROPOSAL_KEX_ALGS];
+
+ if (options.gss_trust_dns)
+ gss_host = (char *)get_canonical_hostname(1);
+ else
+ gss_host = host;
+
+ gss = ssh_gssapi_client_mechanisms(gss_host);
+ if (gss) {
+ debug("Offering GSSAPI proposal: %s", gss);
+ xasprintf(&myproposal[PROPOSAL_KEX_ALGS],
+ "%s,%s", gss, orig);
+ }
+ }
+#endif
+
if (options.ciphers == (char *)-1) {
logit("No valid ciphers for protocol version 2 given, using defaults.");
options.ciphers = NULL;
myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
options.hostkeyalgorithms;
+#ifdef GSSAPI
+ /* If we've got GSSAPI algorithms, then we also support the
+ * 'null' hostkey, as a last resort */
+ if (options.gss_keyex && gss) {
+ orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
+ xasprintf(&myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS],
+ "%s,null", orig);
+ }
+#endif
+
if (options.rekey_limit)
packet_set_rekey_limit(options.rekey_limit);
kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
+#ifdef GSSAPI
+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_client;
+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_client;
+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_client;
+#endif
kex->client_version_string=client_version_string;
kex->server_version_string=server_version_string;
kex->verify_host_key=&verify_host_key_callback;
+#ifdef GSSAPI
+ kex->gss_deleg_creds = options.gss_deleg_creds;
+ kex->gss_trust_dns = options.gss_trust_dns;
+ kex->gss_host = gss_host;
+#endif
+
xxx_kex = kex;
dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
void input_gssapi_hash(int type, u_int32_t, void *);
void input_gssapi_error(int, u_int32_t, void *);
void input_gssapi_errtok(int, u_int32_t, void *);
+int userauth_gsskeyex(Authctxt *authctxt);
#endif
void userauth(Authctxt *, char *);
Authmethod authmethods[] = {
#ifdef GSSAPI
+ {"gssapi-keyex",
+ userauth_gsskeyex,
+ &options.gss_authentication,
+ NULL},
{"gssapi-with-mic",
userauth_gssapi,
&options.gss_authentication,
static u_int mech = 0;
OM_uint32 min;
int ok = 0;
+ char *gss_host = NULL;
+
+ if (options.gss_trust_dns)
+ gss_host = (char *)get_canonical_hostname(1);
+ else
+ gss_host = (char *)authctxt->host;
/* Try one GSSAPI method at a time, rather than sending them all at
* once. */
/* My DER encoding requires length<128 */
if (gss_supported->elements[mech].length < 128 &&
ssh_gssapi_check_mechanism(&gssctxt,
- &gss_supported->elements[mech], authctxt->host)) {
+ &gss_supported->elements[mech], gss_host)) {
ok = 1; /* Mechanism works */
} else {
mech++;
{
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt;
- int oidlen;
- char *oidv;
+ u_int oidlen;
+ u_char *oidv;
if (authctxt == NULL)
fatal("input_gssapi_response: no authentication context");
xfree(msg);
xfree(lang);
}
+
+int
+userauth_gsskeyex(Authctxt *authctxt)
+{
+ Buffer b;
+ gss_buffer_desc gssbuf;
+ gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
+ OM_uint32 ms;
+
+ static int attempt = 0;
+ if (attempt++ >= 1)
+ return (0);
+
+ if (gss_kex_context == NULL) {
+ debug("No valid Key exchange context");
+ return (0);
+ }
+
+ ssh_gssapi_buildmic(&b, authctxt->server_user, authctxt->service,
+ "gssapi-keyex");
+
+ gssbuf.value = buffer_ptr(&b);
+ gssbuf.length = buffer_len(&b);
+
+ if (GSS_ERROR(ssh_gssapi_sign(gss_kex_context, &gssbuf, &mic))) {
+ buffer_free(&b);
+ return (0);
+ }
+
+ packet_start(SSH2_MSG_USERAUTH_REQUEST);
+ packet_put_cstring(authctxt->server_user);
+ packet_put_cstring(authctxt->service);
+ packet_put_cstring(authctxt->method->name);
+ packet_put_string(mic.value, mic.length);
+ packet_send();
+
+ buffer_free(&b);
+ gss_release_buffer(&ms, &mic);
+
+ return (1);
+}
+
#endif /* GSSAPI */
int
#include "monitor_fdpass.h"
#include "version.h"
+#ifdef USE_SECURITY_SESSION_API
+#include <Security/AuthSession.h>
+#endif
+
#ifdef LIBWRAP
#include <tcpd.h>
#include <syslog.h>
logit("Disabling protocol version 1. Could not load host key");
options.protocol &= ~SSH_PROTO_1;
}
+#ifndef GSSAPI
+ /* The GSSAPI key exchange can run without a host key */
if ((options.protocol & SSH_PROTO_2) && !sensitive_data.have_ssh2_key) {
logit("Disabling protocol version 2. Could not load host key");
options.protocol &= ~SSH_PROTO_2;
}
+#endif
if (!(options.protocol & (SSH_PROTO_1|SSH_PROTO_2))) {
logit("sshd: no hostkeys available -- exiting.");
exit(1);
/* Log the connection. */
verbose("Connection from %.500s port %d", remote_ip, remote_port);
+#ifdef USE_SECURITY_SESSION_API
+ /*
+ * Create a new security session for use by the new user login if
+ * the current session is the root session or we are not launched
+ * by inetd (eg: debugging mode or server mode). We do not
+ * necessarily need to create a session if we are launched from
+ * inetd because Panther xinetd will create a session for us.
+ *
+ * The only case where this logic will fail is if there is an
+ * inetd running in a non-root session which is not creating
+ * new sessions for us. Then all the users will end up in the
+ * same session (bad).
+ *
+ * When the client exits, the session will be destroyed for us
+ * automatically.
+ *
+ * We must create the session before any credentials are stored
+ * (including AFS pags, which happens a few lines below).
+ */
+ {
+ OSStatus err = 0;
+ SecuritySessionId sid = 0;
+ SessionAttributeBits sattrs = 0;
+
+ err = SessionGetInfo(callerSecuritySession, &sid, &sattrs);
+ if (err)
+ error("SessionGetInfo() failed with error %.8X",
+ (unsigned) err);
+ else
+ debug("Current Session ID is %.8X / Session Attributes are %.8X",
+ (unsigned) sid, (unsigned) sattrs);
+
+ if (inetd_flag && !(sattrs & sessionIsRoot))
+ debug("Running in inetd mode in a non-root session... "
+ "assuming inetd created the session for us.");
+ else {
+ debug("Creating new security session...");
+ err = SessionCreate(0, sessionHasTTY | sessionIsRemote);
+ if (err)
+ error("SessionCreate() failed with error %.8X",
+ (unsigned) err);
+
+ err = SessionGetInfo(callerSecuritySession, &sid,
+ &sattrs);
+ if (err)
+ error("SessionGetInfo() failed with error %.8X",
+ (unsigned) err);
+ else
+ debug("New Session ID is %.8X / Session Attributes are %.8X",
+ (unsigned) sid, (unsigned) sattrs);
+ }
+ }
+#endif
+
/*
* We don't want to listen forever unless the other side
* successfully authenticates itself. So we set up an alarm which is
myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = list_hostkey_types();
+#ifdef GSSAPI
+ {
+ char *orig;
+ char *gss = NULL;
+ char *newstr = NULL;
+ orig = myproposal[PROPOSAL_KEX_ALGS];
+
+ /*
+ * If we don't have a host key, then there's no point advertising
+ * the other key exchange algorithms
+ */
+
+ if (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS]) == 0)
+ orig = NULL;
+
+ if (options.gss_keyex)
+ gss = ssh_gssapi_server_mechanisms();
+ else
+ gss = NULL;
+
+ if (gss && orig)
+ xasprintf(&newstr, "%s,%s", gss, orig);
+ else if (gss)
+ newstr = gss;
+ else if (orig)
+ newstr = orig;
+
+ /*
+ * If we've got GSSAPI mechanisms, then we've got the 'null' host
+ * key alg, but we can't tell people about it unless its the only
+ * host key algorithm we support
+ */
+ if (gss && (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS])) == 0)
+ myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = "null";
+
+ if (newstr)
+ myproposal[PROPOSAL_KEX_ALGS] = newstr;
+ else
+ fatal("No supported key exchange algorithms");
+ }
+#endif
+
/* start key exchange */
kex = kex_setup(myproposal);
kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
+#ifdef GSSAPI
+ kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server;
+ kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_server;
+ kex->kex[KEX_GSS_GEX_SHA1] = kexgss_server;
+#endif
kex->server = 1;
kex->client_version_string=client_version_string;
kex->server_version_string=server_version_string;
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
+#GSSAPIStrictAcceptorCheck yes
+#GSSAPIKeyExchange no
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
The default is
.Dq no .
Note that this option applies to protocol version 2 only.
+.It Cm GSSAPIKeyExchange
+Specifies whether key exchange based on GSSAPI is allowed. GSSAPI key exchange
+doesn't rely on ssh keys to verify host identity.
+The default is
+.Dq no .
+Note that this option applies to protocol version 2 only.
.It Cm GSSAPICleanupCredentials
Specifies whether to automatically destroy the user's credentials cache
on logout.
The default is
.Dq yes .
Note that this option applies to protocol version 2 only.
+.It Cm GSSAPIStrictAcceptorCheck
+Determines whether to be strict about the identity of the GSSAPI acceptor
+a client authenticates against. If
+.Dq yes
+then the client must authenticate against the
+.Pa host
+service on the current hostname. If
+.Dq no
+then the client may authenticate against any service key stored in the
+machine's default store. This facility is provided to assist with operation
+on multi homed machines.
+The default is
+.Dq yes .
+Note that this option applies only to protocol version 2 GSSAPI connections,
+and setting it to
+.Dq no
+may only work with recent Kerberos GSSAPI libraries.
.It Cm HostbasedAuthentication
Specifies whether rhosts or /etc/hosts.equiv authentication together
with successful public key client host authentication is allowed
andersk / gssapi-openssh.git / commitdiff
