*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.138 2004/06/13 12:53:24 djm Exp $");
+RCSID("$OpenBSD: sshconnect2.c,v 1.143 2005/10/14 02:17:59 stevesk Exp $");
#include "openbsd-compat/sys-queue.h"
extern char *client_version_string;
extern char *server_version_string;
extern Options options;
+extern Kex *xxx_kex;
+
+/* tty_flag is set in ssh.c. use this in ssh_userauth2 */
+/* if it is set then prevent the switch to the null cipher */
+
+extern int tty_flag;
/*
* SSH2 key exchange
ssh_kex2(char *host, struct sockaddr *hostaddr)
{
Kex *kex;
+
#ifdef GSSAPI
- char *orig, *gss;
+ char *orig = NULL, *gss = NULL;
int len;
+ char *gss_host = NULL;
#endif
xxx_host = host;
/* Add the GSSAPI mechanisms currently supported on this client to
* the key exchange algorithm proposal */
orig = myproposal[PROPOSAL_KEX_ALGS];
- gss = ssh_gssapi_client_mechanisms((char *)get_canonical_hostname(1));
+ 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) {
- len = strlen(orig)+strlen(gss)+2;
- myproposal[PROPOSAL_KEX_ALGS]=xmalloc(len);
- snprintf(myproposal[PROPOSAL_KEX_ALGS],len,"%s,%s",gss,orig);
+ debug("Offering GSSAPI proposal: %s", gss);
+ len = strlen(orig) + strlen(gss) + 2;
+ myproposal[PROPOSAL_KEX_ALGS] = xmalloc(len);
+ snprintf(myproposal[PROPOSAL_KEX_ALGS], len, "%s,%s", gss,
+ orig);
}
}
#endif
if (options.ciphers != NULL) {
myproposal[PROPOSAL_ENC_ALGS_CTOS] =
myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
- }
+ }
+
myproposal[PROPOSAL_ENC_ALGS_CTOS] =
compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
myproposal[PROPOSAL_ENC_ALGS_STOC] =
compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
if (options.compression) {
myproposal[PROPOSAL_COMP_ALGS_CTOS] =
- myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib,none";
+ myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none";
} else {
myproposal[PROPOSAL_COMP_ALGS_CTOS] =
- myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib";
+ myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib";
}
if (options.macs != NULL) {
myproposal[PROPOSAL_MAC_ALGS_CTOS] =
options.hostkeyalgorithms;
#ifdef GSSAPI
- /* If we've got GSSAPI algorithms, then we also support the
- * 'null' hostkey, as a last resort */
+ /* 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];
- len = strlen(orig)+sizeof(",null");
- myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS]=xmalloc(len);
- snprintf(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS],len,"%s,null",orig);
+ orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
+ len = strlen(orig) + sizeof(",null");
+ myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = xmalloc(len);
+ snprintf(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS], len,
+ "%s,null", orig);
}
#endif
kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
#ifdef GSSAPI
kex->kex[KEX_GSS_GRP1_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->options.gss_deleg_creds=options.gss_deleg_creds;
+ 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;
int userauth_hostbased(Authctxt *);
int userauth_kerberos(Authctxt *);
-#ifdef GSSAPI
-int userauth_gssapi(Authctxt *authctxt);
-void input_gssapi_response(int type, u_int32_t, void *);
-void input_gssapi_token(int type, u_int32_t, void *);
-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 *);
-#endif
-
#ifdef GSSAPI
int userauth_external(Authctxt *authctxt);
int userauth_gssapi(Authctxt *authctxt);
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},
{"external-keyx",
userauth_external,
&options.gss_authentication,
pubkey_cleanup(&authctxt);
dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
-
+ if ((options.none_switch == 1) && (options.none_enabled == 1) && !tty_flag) /* no null on tty sessions */
+ {
+ debug("Requesting none rekeying...");
+ myproposal[PROPOSAL_ENC_ALGS_STOC] = "none";
+ myproposal[PROPOSAL_ENC_ALGS_CTOS] = "none";
+ kex_prop2buf(&xxx_kex->my,myproposal);
+ packet_request_rekeying();
+ fprintf(stderr, "WARNING: ENABLED NULL CIPHER\n");
+ }
debug("Authentication succeeded (%s).", authctxt.method->name);
}
input_userauth_error(int type, u_int32_t seq, void *ctxt)
{
fatal("input_userauth_error: bad message during authentication: "
- "type %d", type);
+ "type %d", type);
}
void
{
Gssctxt *gssctxt = NULL;
static gss_OID_set gss_supported = NULL;
- static int mech = 0;
+ static u_int mech = 0;
OM_uint32 min;
int ok = 0;
+ char *gss_host = NULL;
if (!options.gss_authentication) {
verbose("GSSAPI authentication disabled.");
return 0;
}
+ 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(&gss_supported->elements[mech],
- get_canonical_hostname(1)) &&
+ gss_host) &&
!GSS_ERROR(ssh_gssapi_import_name(gssctxt,
- get_canonical_hostname(1)))) {
+ gss_host))) {
ok = 1; /* Mechanism works */
} else {
mech++;
}
}
- if (!ok) return 0;
+ if (!ok)
+ return 0;
authctxt->methoddata=(void *)gssctxt;
packet_put_int(1);
- /* Some servers encode the OID incorrectly (as we used to) */
- if (datafellows & SSH_BUG_GSSAPI_BER) {
- packet_put_string(gss_supported->elements[mech].elements,
- gss_supported->elements[mech].length);
- } else {
- packet_put_int((gss_supported->elements[mech].length)+2);
- packet_put_char(SSH_GSS_OIDTYPE);
- packet_put_char(gss_supported->elements[mech].length);
- packet_put_raw(gss_supported->elements[mech].elements,
- gss_supported->elements[mech].length);
- }
+ packet_put_int((gss_supported->elements[mech].length) + 2);
+ packet_put_char(SSH_GSS_OIDTYPE);
+ packet_put_char(gss_supported->elements[mech].length);
+ packet_put_raw(gss_supported->elements[mech].elements,
+ gss_supported->elements[mech].length);
packet_send();
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt = authctxt->methoddata;
gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
- gss_buffer_desc gssbuf, mic;
+ gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
+ gss_buffer_desc gssbuf;
OM_uint32 status, ms, flags;
Buffer b;
{
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt;
- int oidlen;
- char *oidv;
+ unsigned int oidlen;
+ unsigned char *oidv;
if (authctxt == NULL)
fatal("input_gssapi_response: no authentication context");
/* Setup our OID */
oidv = packet_get_string(&oidlen);
- if (datafellows & SSH_BUG_GSSAPI_BER) {
- if (!ssh_gssapi_check_oid(gssctxt, oidv, oidlen))
- fatal("Server returned different OID than expected");
- } else {
- if(oidv[0] != SSH_GSS_OIDTYPE || oidv[1] != oidlen-2) {
- debug("Badly encoded mechanism OID received");
- userauth(authctxt, NULL);
- xfree(oidv);
- return;
- }
- if (!ssh_gssapi_check_oid(gssctxt, oidv+2, oidlen-2))
- fatal("Server returned different OID than expected");
+ if (oidlen <= 2 ||
+ oidv[0] != SSH_GSS_OIDTYPE ||
+ oidv[1] != oidlen - 2) {
+ xfree(oidv);
+ debug("Badly encoded mechanism OID received");
+ userauth(authctxt, NULL);
+ return;
}
+ if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
+ fatal("Server returned different OID than expected");
+
packet_check_eom();
xfree(oidv);
/* Stick it into GSSAPI and see what it says */
status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
- &recv_tok, &send_tok, NULL);
+ &recv_tok, &send_tok, NULL);
xfree(recv_tok.value);
gss_release_buffer(&ms, &send_tok);
packet_check_eom();
- debug("Server GSSAPI Error:\n%s\n", msg);
+ debug("Server GSSAPI Error:\n%s", msg);
xfree(msg);
xfree(lang);
}
+#ifdef GSI
+extern
+const gss_OID_desc * const gss_mech_globus_gssapi_openssl;
+#define is_gsi_oid(oid) \
+ (oid->length == gss_mech_globus_gssapi_openssl->length && \
+ (memcmp(oid->elements, gss_mech_globus_gssapi_openssl->elements, \
+ oid->length) == 0))
+#endif
+
int
userauth_external(Authctxt *authctxt)
{
/* The client MUST NOT try this method if initial key exchange
was not performed using a GSSAPI-based key exchange
method. */
- if (xxx_kex->kex_type != KEX_GSS_GRP1_SHA1) {
+ if (gss_kex_context == NULL) {
debug2("gsskex not performed, skipping external-keyx");
return 0;
}
debug2("userauth_external");
packet_start(SSH2_MSG_USERAUTH_REQUEST);
#ifdef GSI
- if(options.implicit && !(datafellows & SSH_BUG_GSS_EMPTYUSER)) {
- packet_put_cstring("");
+ if (options.implicit && is_gsi_oid(gss_kex_context->oid)) {
+ packet_put_cstring("");
} else {
#endif
- packet_put_cstring(authctxt->server_user);
+ packet_put_cstring(authctxt->server_user);
#ifdef GSI
}
#endif
packet_write_wait();
return 1;
}
+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);
+ }
+
+#ifdef GSI
+ if (options.implicit && is_gsi_oid(gss_kex_context->oid)) {
+ ssh_gssapi_buildmic(&b, "", authctxt->service, "gssapi-keyex");
+ } else {
+#endif
+ ssh_gssapi_buildmic(&b, authctxt->server_user, authctxt->service,
+ "gssapi-keyex");
+#ifdef GSI
+ }
+#endif
+
+ 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);
+#ifdef GSI
+ if (options.implicit && is_gsi_oid(gss_kex_context->oid)) {
+ packet_put_cstring("");
+ } else {
+#endif
+ packet_put_cstring(authctxt->server_user);
+#ifdef GSI
+ }
+#endif
+ 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