*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.114 2003/04/01 10:22:21 markus Exp $");
+RCSID("$OpenBSD: sshconnect2.c,v 1.143 2005/10/14 02:17:59 stevesk Exp $");
+
+#include "openbsd-compat/sys-queue.h"
#include "ssh.h"
#include "ssh2.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
*/
u_char *session_id2 = NULL;
-int session_id2_len = 0;
+u_int session_id2_len = 0;
char *xxx_host;
struct sockaddr *xxx_hostaddr;
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
if (options.ciphers == (char *)-1) {
- log("No valid ciphers for protocol version 2 given, using defaults.");
+ logit("No valid ciphers for protocol version 2 given, using defaults.");
options.ciphers = NULL;
}
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
+
+ if (options.rekey_limit)
+ packet_set_rekey_limit(options.rekey_limit);
+
/* 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;
dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
typedef struct Authctxt Authctxt;
typedef struct Authmethod Authmethod;
-
-typedef int sign_cb_fn(
- Authctxt *authctxt, Key *key,
- u_char **sigp, u_int *lenp, u_char *data, u_int datalen);
+typedef struct identity Identity;
+typedef struct idlist Idlist;
+
+struct identity {
+ TAILQ_ENTRY(identity) next;
+ AuthenticationConnection *ac; /* set if agent supports key */
+ Key *key; /* public/private key */
+ char *filename; /* comment for agent-only keys */
+ int tried;
+ int isprivate; /* key points to the private key */
+};
+TAILQ_HEAD(idlist, identity);
struct Authctxt {
const char *server_user;
int success;
char *authlist;
/* pubkey */
- Key *last_key;
- sign_cb_fn *last_key_sign;
- int last_key_hint;
+ Idlist keys;
AuthenticationConnection *agent;
/* hostbased */
Sensitive *sensitive;
int userauth_passwd(Authctxt *);
int userauth_kbdint(Authctxt *);
int userauth_hostbased(Authctxt *);
+int userauth_kerberos(Authctxt *);
#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 *);
-static int sign_and_send_pubkey(Authctxt *, Key *, sign_cb_fn *);
-static void clear_auth_state(Authctxt *);
+static int sign_and_send_pubkey(Authctxt *, Identity *);
+static void pubkey_prepare(Authctxt *);
+static void pubkey_cleanup(Authctxt *);
+static Key *load_identity_file(char *);
static Authmethod *authmethod_get(char *authlist);
static Authmethod *authmethod_lookup(const char *name);
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,
/* setup authentication context */
memset(&authctxt, 0, sizeof(authctxt));
- authctxt.agent = ssh_get_authentication_connection();
+ pubkey_prepare(&authctxt);
authctxt.server_user = server_user;
authctxt.local_user = local_user;
authctxt.host = host;
dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
- if (authctxt.agent != NULL)
- ssh_close_authentication_connection(authctxt.agent);
-
+ 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);
}
+
void
userauth(Authctxt *authctxt, char *authlist)
{
- if (authctxt->methoddata!=NULL) {
+ if (authctxt->methoddata) {
xfree(authctxt->methoddata);
- authctxt->methoddata=NULL;
+ authctxt->methoddata = NULL;
}
-
if (authlist == NULL) {
authlist = authctxt->authlist;
} else {
if (method == NULL)
fatal("Permission denied (%s).", authlist);
authctxt->method = method;
+
+ /* reset the per method handler */
+ dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
+ SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
+
+ /* and try new method */
if (method->userauth(authctxt) != 0) {
debug2("we sent a %s packet, wait for reply", method->name);
break;
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);
- fprintf(stderr, "%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);
- clear_auth_state(authctxt);
+ authctxt->methoddata = NULL;
+ }
authctxt->success = 1; /* break out */
}
packet_check_eom();
if (partial != 0)
- log("Authenticated with partial success.");
+ logit("Authenticated with partial success.");
debug("Authentications that can continue: %s", authlist);
- clear_auth_state(authctxt);
userauth(authctxt, authlist);
}
void
{
Authctxt *authctxt = ctxt;
Key *key = NULL;
+ Identity *id = NULL;
Buffer b;
int pktype, sent = 0;
u_int alen, blen;
}
packet_check_eom();
- debug("Server accepts key: pkalg %s blen %u lastkey %p hint %d",
- pkalg, blen, authctxt->last_key, authctxt->last_key_hint);
+ debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
- do {
- if (authctxt->last_key == NULL ||
- authctxt->last_key_sign == NULL) {
- debug("no last key or no sign cb");
- break;
- }
- if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
- debug("unknown pkalg %s", pkalg);
- break;
- }
- if ((key = key_from_blob(pkblob, blen)) == NULL) {
- debug("no key from blob. pkalg %s", pkalg);
- break;
- }
- if (key->type != pktype) {
- error("input_userauth_pk_ok: type mismatch "
- "for decoded key (received %d, expected %d)",
- key->type, pktype);
- break;
- }
- fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
- debug2("input_userauth_pk_ok: fp %s", fp);
- xfree(fp);
- if (!key_equal(key, authctxt->last_key)) {
- debug("key != last_key");
+ if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
+ debug("unknown pkalg %s", pkalg);
+ goto done;
+ }
+ if ((key = key_from_blob(pkblob, blen)) == NULL) {
+ debug("no key from blob. pkalg %s", pkalg);
+ goto done;
+ }
+ if (key->type != pktype) {
+ error("input_userauth_pk_ok: type mismatch "
+ "for decoded key (received %d, expected %d)",
+ key->type, pktype);
+ goto done;
+ }
+ fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
+ debug2("input_userauth_pk_ok: fp %s", fp);
+ xfree(fp);
+
+ /*
+ * 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;
}
- sent = sign_and_send_pubkey(authctxt, key,
- authctxt->last_key_sign);
- } while (0);
-
+ }
+done:
if (key != NULL)
key_free(key);
xfree(pkalg);
xfree(pkblob);
- /* unregister */
- clear_auth_state(authctxt);
- dispatch_set(SSH2_MSG_USERAUTH_PK_OK, NULL);
-
/* try another method if we did not send a packet */
if (sent == 0)
userauth(authctxt, NULL);
-
}
#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;
-
- /* Things work better if we send one mechanism at a time, rather
- * than them all at once. This means that if we fail at some point
- * in the middle of a negotiation, we can come back and try something
- * different. */
-
- if (datafellows & SSH_OLD_GSSAPI) return 0;
-
- /* Before we offer a mechanism, check that we can support it. Don't
- * bother trying to get credentials - as the standard fallback will
- * deal with that kind of failure.
- */
+ 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 (gss_supported == NULL)
+ gss_indicate_mechs(&min, &gss_supported);
- if (supported==NULL) gss_indicate_mechs(&min, &supported);
-
- while (mech<supported->count && !ok) {
- if (gssctxt) ssh_gssapi_delete_ctx(&gssctxt);
+ /* Check to see if the mechanism is usable before we offer it */
+ 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]);
- /* The DER encoding below only works for lengths<128,
- * so check this here
- */
- if (supported->elements[mech].length<128 &&
+ /* My DER encoding requires 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))) {
- ok = 1; /* Mechanism works */
+ gss_host))) {
+ ok = 1; /* Mechanism works */
} else {
mech++;
}
}
-
- if (!ok) return 0;
-
+
+ if (!ok)
+ return 0;
+
authctxt->methoddata=(void *)gssctxt;
-
+
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_cstring(authctxt->method->name);
+
packet_put_int(1);
- /* The newest gsskeyex draft stipulates that OIDs should
- * be DER encoded, so we need to add the object type and
- * length information back on */
- 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(0x06);
- 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();
- packet_write_wait();
+ packet_send();
+
+ dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
+ dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
+ dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
+ dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
- dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE,&input_gssapi_response);
- dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN,&input_gssapi_token);
- dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR,&input_gssapi_error);
- dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK,&input_gssapi_errtok);
-
mech++; /* Move along to next candidate */
- return 1;
+ 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)
+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;
-
+ unsigned int oidlen;
+ unsigned char *oidv;
+
if (authctxt == NULL)
fatal("input_gssapi_response: no authentication context");
gssctxt = authctxt->methoddata;
-
+
/* 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");
- }
- ssh_gssapi_set_oid_data(gssctxt,oidv,oidlen);
- } else {
- if(oidv[0]!=0x06 || oidv[1]!=oidlen-2) {
- debug("Badly encoded mechanism OID received");
- clear_auth_state(authctxt);
- userauth(authctxt,NULL);
- return;
- }
- if (!ssh_gssapi_check_oid(gssctxt,oidv+2,oidlen-2)) {
- fatal("Server returned different OID than expected");
- }
- ssh_gssapi_set_oid_data(gssctxt,oidv+2,oidlen-2);
+ oidv = packet_get_string(&oidlen);
+
+ 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();
-
- 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();
- packet_write_wait();
- }
+
+ xfree(oidv);
+
+ if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
/* Start again with next method on list */
debug("Trying to start again");
- clear_auth_state(authctxt);
- userauth(authctxt,NULL);
+ 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();
- packet_write_wait();
- 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,recv_tok;
+ gss_buffer_desc recv_tok;
OM_uint32 status;
u_int slen;
-
+
if (authctxt == NULL)
- fatal("input_gssapi_token: no authentication context");
- gssctxt = authctxt->methoddata;
-
- recv_tok.value=packet_get_string(&slen);
- recv_tok.length=slen; /* safe typecast */
+ fatal("input_gssapi_response: no authentication context");
- status=ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
- &recv_tok, &send_tok, NULL);
+ recv_tok.value = packet_get_string(&slen);
+ recv_tok.length = slen; /* safe typecast */
packet_check_eom();
-
+
+ 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();
- packet_write_wait();
- }
/* Start again with the next method in the list */
- clear_auth_state(authctxt);
- userauth(authctxt,NULL);
+ 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();
- packet_write_wait();
- }
-
- if (status == GSS_S_COMPLETE) {
- /* If that succeeded, send a exchange complete message */
- packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
- packet_send();
- packet_write_wait();
- }
}
void
{
Authctxt *authctxt = ctxt;
Gssctxt *gssctxt;
- gss_buffer_desc send_tok,recv_tok;
- OM_uint32 status;
-
+ gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
+ gss_buffer_desc recv_tok;
+ OM_uint32 status, ms;
+ u_int len;
+
if (authctxt == NULL)
fatal("input_gssapi_response: no authentication context");
gssctxt = authctxt->methoddata;
-
- recv_tok.value=packet_get_string(&recv_tok.length);
- /* 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.value = packet_get_string(&len);
+ recv_tok.length = len;
packet_check_eom();
-
- /* We can't send a packet to the server */
-
- /* The draft says that we should wait for the server to fail
- * before starting the next authentication. So, we clear the
- * state, but don't do anything else */
- clear_auth_state(authctxt);
- return;
+
+ /* Stick it into GSSAPI and see what it says */
+ status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
+ &recv_tok, &send_tok, NULL);
+
+ xfree(recv_tok.value);
+ gss_release_buffer(&ms, &send_tok);
+
+ /* Server will be returning a failed packet after this one */
}
void
input_gssapi_error(int type, u_int32_t plen, void *ctxt)
{
- OM_uint32 maj,min;
+ OM_uint32 maj, min;
char *msg;
char *lang;
-
+
maj=packet_get_int();
min=packet_get_int();
msg=packet_get_string(NULL);
lang=packet_get_string(NULL);
packet_check_eom();
-
- fprintf(stderr, "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)
{
- static int attempt =0;
+ static int attempt = 0;
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
packet_put_cstring(authctxt->method->name);
packet_send();
return 1;
-
}
int
info = packet_get_string(NULL);
lang = packet_get_string(NULL);
if (strlen(info) > 0)
- log("%s", info);
+ logit("%s", info);
xfree(info);
xfree(lang);
packet_start(SSH2_MSG_USERAUTH_REQUEST);
if (strcmp(password, retype) != 0) {
memset(password, 0, strlen(password));
xfree(password);
- log("Mismatch; try again, EOF to quit.");
+ logit("Mismatch; try again, EOF to quit.");
password = NULL;
}
memset(retype, 0, strlen(retype));
&input_userauth_passwd_changereq);
}
-static void
-clear_auth_state(Authctxt *authctxt)
+static int
+identity_sign(Identity *id, u_char **sigp, u_int *lenp,
+ u_char *data, u_int datalen)
{
- /* XXX clear authentication state */
- dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, NULL);
-#ifdef GSSAPI
- dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE,NULL);
- dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN,NULL);
- dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR,NULL);
-#endif
-
- if (authctxt->last_key != NULL && authctxt->last_key_hint == -1) {
- debug3("clear_auth_state: key_free %p", authctxt->last_key);
- key_free(authctxt->last_key);
- }
- authctxt->last_key = NULL;
- authctxt->last_key_hint = -2;
- authctxt->last_key_sign = NULL;
+ Key *prv;
+ int ret;
+
+ /* the agent supports this key */
+ if (id->ac)
+ return (ssh_agent_sign(id->ac, id->key, sigp, lenp,
+ data, datalen));
+ /*
+ * we have already loaded the private key or
+ * the private key is stored in external hardware
+ */
+ if (id->isprivate || (id->key->flags & KEY_FLAG_EXT))
+ return (key_sign(id->key, sigp, lenp, data, datalen));
+ /* load the private key from the file */
+ if ((prv = load_identity_file(id->filename)) == NULL)
+ return (-1);
+ ret = key_sign(prv, sigp, lenp, data, datalen);
+ key_free(prv);
+ return (ret);
}
static int
-sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback)
+sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
{
Buffer b;
u_char *blob, *signature;
u_int bloblen, slen;
- int skip = 0;
+ u_int skip = 0;
int ret = -1;
int have_sig = 1;
debug3("sign_and_send_pubkey");
- if (key_to_blob(k, &blob, &bloblen) == 0) {
+ if (key_to_blob(id->key, &blob, &bloblen) == 0) {
/* we cannot handle this key */
debug3("sign_and_send_pubkey: cannot handle key");
return 0;
} else {
buffer_put_cstring(&b, authctxt->method->name);
buffer_put_char(&b, have_sig);
- buffer_put_cstring(&b, key_ssh_name(k));
+ buffer_put_cstring(&b, key_ssh_name(id->key));
}
buffer_put_string(&b, blob, bloblen);
/* generate signature */
- ret = (*sign_callback)(authctxt, k, &signature, &slen,
+ ret = identity_sign(id, &signature, &slen,
buffer_ptr(&b), buffer_len(&b));
if (ret == -1) {
xfree(blob);
buffer_put_cstring(&b, authctxt->method->name);
buffer_put_char(&b, have_sig);
if (!(datafellows & SSH_BUG_PKAUTH))
- buffer_put_cstring(&b, key_ssh_name(k));
+ buffer_put_cstring(&b, key_ssh_name(id->key));
buffer_put_string(&b, blob, bloblen);
}
xfree(blob);
}
static int
-send_pubkey_test(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback,
- int hint)
+send_pubkey_test(Authctxt *authctxt, Identity *id)
{
u_char *blob;
u_int bloblen, have_sig = 0;
debug3("send_pubkey_test");
- if (key_to_blob(k, &blob, &bloblen) == 0) {
+ if (key_to_blob(id->key, &blob, &bloblen) == 0) {
/* we cannot handle this key */
debug3("send_pubkey_test: cannot handle key");
return 0;
}
/* register callback for USERAUTH_PK_OK message */
- authctxt->last_key_sign = sign_callback;
- authctxt->last_key_hint = hint;
- authctxt->last_key = k;
dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
packet_start(SSH2_MSG_USERAUTH_REQUEST);
packet_put_cstring(authctxt->method->name);
packet_put_char(have_sig);
if (!(datafellows & SSH_BUG_PKAUTH))
- packet_put_cstring(key_ssh_name(k));
+ packet_put_cstring(key_ssh_name(id->key));
packet_put_string(blob, bloblen);
xfree(blob);
packet_send();
return private;
}
-static int
-identity_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp,
- u_char *data, u_int datalen)
-{
- Key *private;
- int idx, ret;
-
- idx = authctxt->last_key_hint;
- if (idx < 0)
- return -1;
-
- /* private key is stored in external hardware */
- if (options.identity_keys[idx]->flags & KEY_FLAG_EXT)
- return key_sign(options.identity_keys[idx], sigp, lenp, data, datalen);
-
- private = load_identity_file(options.identity_files[idx]);
- if (private == NULL)
- return -1;
- ret = key_sign(private, sigp, lenp, data, datalen);
- key_free(private);
- return ret;
-}
-
-static int
-agent_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp,
- u_char *data, u_int datalen)
-{
- return ssh_agent_sign(authctxt->agent, key, sigp, lenp, data, datalen);
-}
-
-static int
-key_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp,
- u_char *data, u_int datalen)
+/*
+ * try keys in the following order:
+ * 1. agent keys that are found in the config file
+ * 2. other agent keys
+ * 3. keys that are only listed in the config file
+ */
+static void
+pubkey_prepare(Authctxt *authctxt)
{
- return key_sign(key, sigp, lenp, data, datalen);
+ Identity *id;
+ Idlist agent, files, *preferred;
+ Key *key;
+ AuthenticationConnection *ac;
+ char *comment;
+ int i, found;
+
+ TAILQ_INIT(&agent); /* keys from the agent */
+ TAILQ_INIT(&files); /* keys from the config file */
+ preferred = &authctxt->keys;
+ TAILQ_INIT(preferred); /* preferred order of keys */
+
+ /* list of keys stored in the filesystem */
+ for (i = 0; i < options.num_identity_files; i++) {
+ key = options.identity_keys[i];
+ if (key && key->type == KEY_RSA1)
+ continue;
+ options.identity_keys[i] = NULL;
+ id = xmalloc(sizeof(*id));
+ memset(id, 0, sizeof(*id));
+ id->key = key;
+ id->filename = xstrdup(options.identity_files[i]);
+ TAILQ_INSERT_TAIL(&files, id, next);
+ }
+ /* list of keys supported by the agent */
+ if ((ac = ssh_get_authentication_connection())) {
+ for (key = ssh_get_first_identity(ac, &comment, 2);
+ key != NULL;
+ key = ssh_get_next_identity(ac, &comment, 2)) {
+ found = 0;
+ TAILQ_FOREACH(id, &files, next) {
+ /* agent keys from the config file are preferred */
+ if (key_equal(key, id->key)) {
+ key_free(key);
+ xfree(comment);
+ TAILQ_REMOVE(&files, id, next);
+ TAILQ_INSERT_TAIL(preferred, id, next);
+ id->ac = ac;
+ found = 1;
+ break;
+ }
+ }
+ if (!found && !options.identities_only) {
+ id = xmalloc(sizeof(*id));
+ memset(id, 0, sizeof(*id));
+ id->key = key;
+ id->filename = comment;
+ id->ac = ac;
+ TAILQ_INSERT_TAIL(&agent, id, next);
+ }
+ }
+ /* append remaining agent keys */
+ for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
+ TAILQ_REMOVE(&agent, id, next);
+ TAILQ_INSERT_TAIL(preferred, id, next);
+ }
+ authctxt->agent = ac;
+ }
+ /* append remaining keys from the config file */
+ for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
+ TAILQ_REMOVE(&files, id, next);
+ TAILQ_INSERT_TAIL(preferred, id, next);
+ }
+ TAILQ_FOREACH(id, preferred, next) {
+ debug2("key: %s (%p)", id->filename, id->key);
+ }
}
-static int
-userauth_pubkey_agent(Authctxt *authctxt)
+static void
+pubkey_cleanup(Authctxt *authctxt)
{
- static int called = 0;
- int ret = 0;
- char *comment;
- Key *k;
-
- if (called == 0) {
- if (ssh_get_num_identities(authctxt->agent, 2) == 0)
- debug2("userauth_pubkey_agent: no keys at all");
- called = 1;
- }
- k = ssh_get_next_identity(authctxt->agent, &comment, 2);
- if (k == NULL) {
- debug2("userauth_pubkey_agent: no more keys");
- } else {
- debug("Offering agent key: %s", comment);
- xfree(comment);
- ret = send_pubkey_test(authctxt, k, agent_sign_cb, -1);
- if (ret == 0)
- key_free(k);
+ Identity *id;
+
+ if (authctxt->agent != NULL)
+ ssh_close_authentication_connection(authctxt->agent);
+ for (id = TAILQ_FIRST(&authctxt->keys); id;
+ id = TAILQ_FIRST(&authctxt->keys)) {
+ TAILQ_REMOVE(&authctxt->keys, id, next);
+ if (id->key)
+ key_free(id->key);
+ if (id->filename)
+ xfree(id->filename);
+ xfree(id);
}
- if (ret == 0)
- debug2("userauth_pubkey_agent: no message sent");
- return ret;
}
int
userauth_pubkey(Authctxt *authctxt)
{
- static int idx = 0;
+ Identity *id;
int sent = 0;
- Key *key;
- char *filename;
- if (authctxt->agent != NULL) {
- do {
- sent = userauth_pubkey_agent(authctxt);
- } while (!sent && authctxt->agent->howmany > 0);
- }
- while (!sent && idx < options.num_identity_files) {
- key = options.identity_keys[idx];
- filename = options.identity_files[idx];
- if (key == NULL) {
- debug("Trying private key: %s", filename);
- key = load_identity_file(filename);
- if (key != NULL) {
- sent = sign_and_send_pubkey(authctxt, key,
- key_sign_cb);
- key_free(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);
+ /*
+ * send a test message if we have the public key. for
+ * encrypted keys we cannot do this and have to load the
+ * private key instead
+ */
+ if (id->key && id->key->type != KEY_RSA1) {
+ debug("Offering public key: %s", id->filename);
+ sent = send_pubkey_test(authctxt, id);
+ } else if (id->key == NULL) {
+ debug("Trying private key: %s", id->filename);
+ id->key = load_identity_file(id->filename);
+ if (id->key != NULL) {
+ id->isprivate = 1;
+ sent = sign_and_send_pubkey(authctxt, id);
+ key_free(id->key);
+ id->key = NULL;
}
- } else if (key->type != KEY_RSA1) {
- debug("Offering public key: %s", filename);
- sent = send_pubkey_test(authctxt, key,
- identity_sign_cb, idx);
}
- idx++;
+ if (sent)
+ return (sent);
}
- return sent;
+ return (0);
}
/*
inst = packet_get_string(NULL);
lang = packet_get_string(NULL);
if (strlen(name) > 0)
- log("%s", name);
+ logit("%s", name);
if (strlen(inst) > 0)
- log("%s", inst);
+ logit("%s", inst);
xfree(name);
xfree(inst);
xfree(lang);
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;
}