*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.124 2003/08/25 10:33:33 djm Exp $");
+RCSID("$OpenBSD: sshconnect2.c,v 1.143 2005/10/14 02:17:59 stevesk Exp $");
#include "openbsd-compat/sys-queue.h"
#include "authfd.h"
#include "log.h"
#include "readconf.h"
-#include "readpass.h"
+#include "misc.h"
#include "match.h"
#include "dispatch.h"
#include "canohost.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;
#ifdef GSSAPI
if (options.gss_keyex) {
- char *canonhost;
/* Add the GSSAPI mechanisms currently supported on this client to
* the key exchange algorithm proposal */
orig = myproposal[PROPOSAL_KEX_ALGS];
- canonhost = xstrdup(get_canonical_hostname(1));
- resolve_localhost(&canonhost);
- gss = ssh_gssapi_client_mechanisms(canonhost);
- xfree(canonhost);
- canonhost=NULL;
+ 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
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
/* start key exchange */
kex = kex_setup(myproposal);
kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
+ kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
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);
+int userauth_gssapi_with_mic(Authctxt *authctxt);
+int userauth_gssapi_without_mic(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 *);
+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,
NULL},
+ {"gssapi-with-mic",
+ userauth_gssapi,
+ &options.gss_authentication,
+ NULL},
{"gssapi",
userauth_gssapi,
&options.gss_authentication,
pubkey_cleanup(&authctxt);
dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
-
+ if ((options.none_switch == 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
input_userauth_banner(int type, u_int32_t seq, void *ctxt)
{
char *msg, *lang;
+
debug3("input_userauth_banner");
msg = packet_get_string(NULL);
lang = packet_get_string(NULL);
- logit("%s", msg);
+ if (options.log_level > SYSLOG_LEVEL_QUIET)
+ fprintf(stderr, "%s", msg);
xfree(msg);
xfree(lang);
}
Authctxt *authctxt = ctxt;
if (authctxt == NULL)
fatal("input_userauth_success: no authentication context");
- if (authctxt->authlist)
+ if (authctxt->authlist) {
xfree(authctxt->authlist);
- if (authctxt->methoddata)
+ authctxt->authlist = NULL;
+ }
+ if (authctxt->methoddata) {
xfree(authctxt->methoddata);
+ authctxt->methoddata = NULL;
+ }
authctxt->success = 1; /* break out */
}
debug2("input_userauth_pk_ok: fp %s", fp);
xfree(fp);
- TAILQ_FOREACH(id, &authctxt->keys, next) {
+ /*
+ * search keys in the reverse order, because last candidate has been
+ * moved to the end of the queue. this also avoids confusion by
+ * duplicate keys
+ */
+ TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
if (key_equal(key, id->key)) {
sent = sign_and_send_pubkey(authctxt, id);
break;
}
#ifdef GSSAPI
-int
+int
userauth_gssapi(Authctxt *authctxt)
{
Gssctxt *gssctxt = NULL;
- static gss_OID_set supported = NULL;
- static int mech = 0;
+ static gss_OID_set gss_supported = NULL;
+ 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. */
- if (supported == NULL)
- gss_indicate_mechs(&min, &supported);
+ if (gss_supported == NULL)
+ gss_indicate_mechs(&min, &gss_supported);
/* Check to see if the mechanism is usable before we offer it */
- while (mech<supported->count && !ok) {
+ while (mech < gss_supported->count && !ok) {
if (gssctxt)
ssh_gssapi_delete_ctx(&gssctxt);
ssh_gssapi_build_ctx(&gssctxt);
- ssh_gssapi_set_oid(gssctxt, &supported->elements[mech]);
+ ssh_gssapi_set_oid(gssctxt, &gss_supported->elements[mech]);
/* My DER encoding requires length<128 */
- if (supported->elements[mech].length < 128 &&
+ if (gss_supported->elements[mech].length < 128 &&
+ ssh_gssapi_check_mechanism(&gss_supported->elements[mech],
+ gss_host) &&
!GSS_ERROR(ssh_gssapi_import_name(gssctxt,
- authctxt->host))) {
+ 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(supported->elements[mech].elements,
- supported->elements[mech].length);
- } else {
- packet_put_int((supported->elements[mech].length)+2);
- packet_put_char(SSH_GSS_OIDTYPE);
- packet_put_char(supported->elements[mech].length);
- packet_put_raw(supported->elements[mech].elements,
- 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();
return 1;
}
+static OM_uint32
+process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
+{
+ Authctxt *authctxt = ctxt;
+ Gssctxt *gssctxt = authctxt->methoddata;
+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
+ gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
+ gss_buffer_desc gssbuf;
+ OM_uint32 status, ms, flags;
+ Buffer b;
+
+ status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
+ recv_tok, &send_tok, &flags);
+
+ if (send_tok.length > 0) {
+ if (GSS_ERROR(status))
+ packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
+ else
+ packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
+
+ packet_put_string(send_tok.value, send_tok.length);
+ packet_send();
+ gss_release_buffer(&ms, &send_tok);
+ }
+
+ if (status == GSS_S_COMPLETE) {
+ /* send either complete or MIC, depending on mechanism */
+ if (strcmp(authctxt->method->name,"gssapi")==0 ||
+ (!(flags & GSS_C_INTEG_FLAG))) {
+ packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
+ packet_send();
+ } else {
+ ssh_gssapi_buildmic(&b, authctxt->server_user,
+ authctxt->service, "gssapi-with-mic");
+
+ gssbuf.value = buffer_ptr(&b);
+ gssbuf.length = buffer_len(&b);
+
+ status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
+
+ if (!GSS_ERROR(status)) {
+ packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
+ packet_put_string(mic.value, mic.length);
+
+ packet_send();
+ }
+
+ buffer_free(&b);
+ gss_release_buffer(&ms, &mic);
+ }
+ }
+
+ return status;
+}
+
void
input_gssapi_response(int type, u_int32_t plen, void *ctxt)
{
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt;
- OM_uint32 status, ms;
- int oidlen;
- char *oidv;
- gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
+ 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);
- status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
- GSS_C_NO_BUFFER, &send_tok, NULL);
- if (GSS_ERROR(status)) {
- if (send_tok.length > 0) {
- packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
- packet_put_string(send_tok.value, send_tok.length);
- packet_send();
- gss_release_buffer(&ms, &send_tok);
- }
+ if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
/* Start again with next method on list */
debug("Trying to start again");
userauth(authctxt, NULL);
return;
}
-
- /* We must have data to send */
- packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
- packet_put_string(send_tok.value, send_tok.length);
- packet_send();
- gss_release_buffer(&ms, &send_tok);
}
void
input_gssapi_token(int type, u_int32_t plen, void *ctxt)
{
Authctxt *authctxt = ctxt;
- Gssctxt *gssctxt;
- gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc recv_tok;
- OM_uint32 status, ms;
+ OM_uint32 status;
u_int slen;
if (authctxt == NULL)
fatal("input_gssapi_response: no authentication context");
- gssctxt = authctxt->methoddata;
recv_tok.value = packet_get_string(&slen);
recv_tok.length = slen; /* safe typecast */
packet_check_eom();
- status=ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
- &recv_tok, &send_tok, NULL);
+ status = process_gssapi_token(ctxt, &recv_tok);
xfree(recv_tok.value);
if (GSS_ERROR(status)) {
- if (send_tok.length > 0) {
- packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
- packet_put_string(send_tok.value, send_tok.length);
- packet_send();
- gss_release_buffer(&ms, &send_tok);
- }
/* Start again with the next method in the list */
userauth(authctxt, NULL);
return;
}
-
- if (send_tok.length > 0) {
- packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
- packet_put_string(send_tok.value, send_tok.length);
- packet_send();
- gss_release_buffer(&ms, &send_tok);
- }
-
- if (status == GSS_S_COMPLETE) {
- /* If that succeeded, send a exchange complete message */
- packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
- packet_send();
- }
}
void
/* 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)
{
if (attempt++ >= 1)
return 0;
+ /* The client MUST NOT try this method if initial key exchange
+ was not performed using a GSSAPI-based key exchange
+ method. */
+ 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
key = ssh_get_next_identity(ac, &comment, 2)) {
found = 0;
TAILQ_FOREACH(id, &files, next) {
- /* agent keys from the config file are preferred */
+ /* agent keys from the config file are preferred */
if (key_equal(key, id->key)) {
key_free(key);
xfree(comment);
break;
}
}
- if (!found) {
+ if (!found && !options.identities_only) {
id = xmalloc(sizeof(*id));
memset(id, 0, sizeof(*id));
id->key = key;
while ((id = TAILQ_FIRST(&authctxt->keys))) {
if (id->tried++)
return (0);
+ /* move key to the end of the queue */
TAILQ_REMOVE(&authctxt->keys, id, next);
TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
/*
buffer_init(&b);
buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
buffer_put_string(&b, data, datalen);
- ssh_msg_send(to[1], version, &b);
+ if (ssh_msg_send(to[1], version, &b) == -1)
+ fatal("ssh_keysign: couldn't send request");
if (ssh_msg_recv(from[0], &b) < 0) {
error("ssh_keysign: no reply");
- buffer_clear(&b);
+ buffer_free(&b);
return -1;
}
close(from[0]);
if (buffer_get_char(&b) != version) {
error("ssh_keysign: bad version");
- buffer_clear(&b);
+ buffer_free(&b);
return -1;
}
*sigp = buffer_get_string(&b, lenp);
- buffer_clear(&b);
+ buffer_free(&b);
return 0;
}
andersk / gssapi-openssh.git / blobdiff