+/* $OpenBSD: sshconnect2.c,v 1.160 2006/08/03 03:34:42 deraadt Exp $ */
/*
* Copyright (c) 2000 Markus Friedl. All rights reserved.
*
*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.120 2003/06/24 08:23:46 markus Exp $");
-#ifdef KRB5
-#include <krb5.h>
-#ifndef HEIMDAL
-#define krb5_get_err_text(context,code) error_message(code)
-#endif /* !HEIMDAL */
-#endif
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+
+#include <errno.h>
+#include <pwd.h>
+#include <signal.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
#include "openbsd-compat/sys-queue.h"
+#include "xmalloc.h"
#include "ssh.h"
#include "ssh2.h"
-#include "xmalloc.h"
#include "buffer.h"
#include "packet.h"
#include "compat.h"
-#include "bufaux.h"
#include "cipher.h"
+#include "key.h"
#include "kex.h"
#include "myproposal.h"
#include "sshconnect.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"
#include "msg.h"
#include "pathnames.h"
+#include "uidswap.h"
+
+#ifdef GSSAPI
+#include "ssh-gss.h"
+#endif
/* import */
extern char *client_version_string;
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] =
/* 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;
+ kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
kex->client_version_string=client_version_string;
kex->server_version_string=server_version_string;
kex->verify_host_key=&verify_host_key_callback;
Sensitive *sensitive;
/* kbd-interactive */
int info_req_seen;
+ /* generic */
+ void *methoddata;
};
struct Authmethod {
char *name; /* string to compare against server's list */
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
+
void userauth(Authctxt *, char *);
static int sign_and_send_pubkey(Authctxt *, Identity *);
static char *authmethods_get(void);
Authmethod authmethods[] = {
+#ifdef GSSAPI
+ {"gssapi-with-mic",
+ userauth_gssapi,
+ &options.gss_authentication,
+ NULL},
+#endif
{"hostbased",
userauth_hostbased,
&options.hostbased_authentication,
NULL},
-#if KRB5
- {"kerberos-2@ssh.com",
- userauth_kerberos,
- &options.kerberos_authentication,
- NULL},
-#endif
{"publickey",
userauth_pubkey,
&options.pubkey_authentication,
authctxt.success = 0;
authctxt.method = authmethod_lookup("none");
authctxt.authlist = NULL;
+ authctxt.methoddata = NULL;
authctxt.sensitive = sensitive;
authctxt.info_req_seen = 0;
if (authctxt.method == NULL)
void
userauth(Authctxt *authctxt, char *authlist)
{
+ if (authctxt->methoddata) {
+ xfree(authctxt->methoddata);
+ authctxt->methoddata = NULL;
+ }
if (authlist == NULL) {
authlist = authctxt->authlist;
} else {
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);
+ 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;
userauth(authctxt, NULL);
}
+#ifdef GSSAPI
+int
+userauth_gssapi(Authctxt *authctxt)
+{
+ Gssctxt *gssctxt = NULL;
+ static gss_OID_set gss_supported = NULL;
+ static u_int mech = 0;
+ OM_uint32 min;
+ int ok = 0;
+
+ /* Try one GSSAPI method at a time, rather than sending them all at
+ * once. */
+
+ if (gss_supported == NULL)
+ gss_indicate_mechs(&min, &gss_supported);
+
+ /* 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, &gss_supported->elements[mech]);
+
+ /* My DER encoding requires length<128 */
+ if (gss_supported->elements[mech].length < 128 &&
+ !GSS_ERROR(ssh_gssapi_import_name(gssctxt,
+ authctxt->host))) {
+ ok = 1; /* Mechanism works */
+ } else {
+ mech++;
+ }
+ }
+
+ if (!ok) {
+ ssh_gssapi_delete_ctx(&gssctxt);
+ 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_int(1);
+
+ 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();
+
+ 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;
+}
+
+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 (!(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;
+ int oidlen;
+ char *oidv;
+
+ if (authctxt == NULL)
+ fatal("input_gssapi_response: no authentication context");
+ gssctxt = authctxt->methoddata;
+
+ /* Setup our OID */
+ 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();
+
+ 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");
+ userauth(authctxt, NULL);
+ return;
+ }
+}
+
+void
+input_gssapi_token(int type, u_int32_t plen, void *ctxt)
+{
+ Authctxt *authctxt = ctxt;
+ gss_buffer_desc recv_tok;
+ OM_uint32 status;
+ u_int slen;
+
+ if (authctxt == NULL)
+ fatal("input_gssapi_response: no authentication context");
+
+ 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)) {
+ /* Start again with the next method in the list */
+ userauth(authctxt, NULL);
+ return;
+ }
+}
+
+void
+input_gssapi_errtok(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;
+ u_int len;
+
+ if (authctxt == NULL)
+ fatal("input_gssapi_response: no authentication context");
+ gssctxt = authctxt->methoddata;
+
+ recv_tok.value = packet_get_string(&len);
+ recv_tok.length = len;
+
+ packet_check_eom();
+
+ /* 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;
+ 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();
+
+ debug("Server GSSAPI Error:\n%s", msg);
+ xfree(msg);
+ xfree(lang);
+}
+#endif /* GSSAPI */
+
int
userauth_none(Authctxt *authctxt)
{
{
Key *private;
char prompt[300], *passphrase;
- int quit, i;
+ int perm_ok, quit, i;
struct stat st;
if (stat(filename, &st) < 0) {
debug3("no such identity: %s", filename);
return NULL;
}
- private = key_load_private_type(KEY_UNSPEC, filename, "", NULL);
+ private = key_load_private_type(KEY_UNSPEC, filename, "", NULL, &perm_ok);
+ if (!perm_ok)
+ return NULL;
if (private == NULL) {
if (options.batch_mode)
return NULL;
for (i = 0; i < options.number_of_password_prompts; i++) {
passphrase = read_passphrase(prompt, 0);
if (strcmp(passphrase, "") != 0) {
- private = key_load_private_type(KEY_UNSPEC, filename,
- passphrase, NULL);
+ private = key_load_private_type(KEY_UNSPEC,
+ filename, passphrase, NULL, NULL);
quit = 0;
} else {
debug2("no passphrase given, try next key");
if (key && key->type == KEY_RSA1)
continue;
options.identity_keys[i] = NULL;
- id = xmalloc(sizeof(*id));
- memset(id, 0, sizeof(*id));
+ id = xcalloc(1, sizeof(*id));
id->key = key;
id->filename = xstrdup(options.identity_files[i]);
TAILQ_INSERT_TAIL(&files, id, next);
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) {
- id = xmalloc(sizeof(*id));
- memset(id, 0, sizeof(*id));
+ if (!found && !options.identities_only) {
+ id = xcalloc(1, sizeof(*id));
id->key = key;
id->filename = comment;
id->ac = ac;
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);
/*
return -1;
}
if (pid == 0) {
- seteuid(getuid());
- setuid(getuid());
+ permanently_drop_suid(getuid());
close(from[0]);
if (dup2(from[1], STDOUT_FILENO) < 0)
fatal("ssh_keysign: dup2: %s", strerror(errno));
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;
}
if (p == NULL) {
error("userauth_hostbased: cannot get local ipaddr/name");
key_free(private);
+ xfree(blob);
return 0;
}
len = strlen(p) + 2;
- chost = xmalloc(len);
- strlcpy(chost, p, len);
- strlcat(chost, ".", len);
+ xasprintf(&chost, "%s.", p);
debug2("userauth_hostbased: chost %s", chost);
xfree(p);
error("key_sign failed");
xfree(chost);
xfree(pkalg);
+ xfree(blob);
return 0;
}
packet_start(SSH2_MSG_USERAUTH_REQUEST);
xfree(signature);
xfree(chost);
xfree(pkalg);
+ xfree(blob);
packet_send();
return 1;
}
-#if KRB5
-static int
-ssh_krb5_helper(krb5_data *ap, krb5_context *context)
-{
- krb5_context xcontext = NULL; /* XXX share with ssh1 */
- krb5_auth_context xauth_context = NULL;
- krb5_auth_context *auth_context;
- krb5_error_code problem;
- const char *tkfile;
- struct stat buf;
- krb5_ccache ccache = NULL;
- const char *remotehost;
- int ret;
-
- memset(ap, 0, sizeof(*ap));
-
- context = &xcontext;
- auth_context = &xauth_context;
-
- problem = krb5_init_context(context);
- if (problem) {
- debug("Kerberos v5: krb5_init_context failed");
- ret = 0;
- goto out;
- }
-
- tkfile = krb5_cc_default_name(*context);
- if (strncmp(tkfile, "FILE:", 5) == 0)
- tkfile += 5;
-
- if (stat(tkfile, &buf) == 0 && getuid() != buf.st_uid) {
- debug("Kerberos v5: could not get default ccache (permission denied).");
- ret = 0;
- goto out;
- }
-
- problem = krb5_cc_default(*context, &ccache);
- if (problem) {
- debug("Kerberos v5: krb5_cc_default failed: %s",
- krb5_get_err_text(*context, problem));
- ret = 0;
- goto out;
- }
-
- remotehost = get_canonical_hostname(1);
-
- problem = krb5_mk_req(*context, auth_context, AP_OPTS_MUTUAL_REQUIRED,
- "host", remotehost, NULL, ccache, ap);
- if (problem) {
- debug("Kerberos v5: krb5_mk_req failed: %s",
- krb5_get_err_text(*context, problem));
- ret = 0;
- goto out;
- }
- ret = 1;
-
- out:
- if (ccache != NULL)
- krb5_cc_close(*context, ccache);
- if (*auth_context)
- krb5_auth_con_free(*context, *auth_context);
- return (ret);
-}
-
-int
-userauth_kerberos(Authctxt *authctxt)
-{
- krb5_data ap;
- krb5_context *context;
- int ret = 0;
-
- if (ssh_krb5_helper(&ap, context) == 0)
- goto out;
-
- 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(ap.data, ap.length);
- packet_send();
-
-#ifdef HEIMDAL
- krb5_data_free(&ap);
-#else
- krb5_free_data_contents(*context, &ap);
-#endif
- ret = 1;
-
-out:
- if (*context)
- krb5_free_context(*context);
- return ret;
-}
-#endif
-
/* find auth method */
/*
andersk / openssh.git / blobdiff