]> andersk Git - gssapi-openssh.git/blobdiff - openssh/gss-serv.c
merged OpenSSH 5.1p1 to trunk
[gssapi-openssh.git] / openssh / gss-serv.c
index 748015e915c6f739b1650697d821b5295f327d91..bf88d719278638e9a374cb7c96239c8fa39e156b 100644 (file)
@@ -1,7 +1,7 @@
-/*     $OpenBSD: gss-serv.c,v 1.5 2003/11/17 11:06:07 markus Exp $     */
+/* $OpenBSD: gss-serv.c,v 1.22 2008/05/08 12:02:23 djm 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
 
 #ifdef GSSAPI
 
-#include "ssh.h"
-#include "ssh2.h"
+#include <sys/types.h>
+#include <sys/param.h>
+
+#include <stdarg.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "openbsd-compat/sys-queue.h"
+#include "xmalloc.h"
 #include "buffer.h"
-#include "bufaux.h"
-#include "packet.h"
-#include "compat.h"
-#include <openssl/evp.h>
-#include "cipher.h"
-#include "kex.h"
+#include "key.h"
+#include "hostfile.h"
 #include "auth.h"
 #include "log.h"
 #include "channels.h"
 #include "session.h"
-#include "dispatch.h"
+#include "misc.h"
 #include "servconf.h"
-#include "monitor_wrap.h"
-#include "xmalloc.h"
-#include "getput.h"
 
+#include "xmalloc.h"
 #include "ssh-gss.h"
+#include "monitor_wrap.h"
 
 extern ServerOptions options;
-extern u_char *session_id2;
-extern int session_id2_len;
+extern Authctxt *the_authctxt;
 
 static ssh_gssapi_client gssapi_client =
     { GSS_C_EMPTY_BUFFER, GSS_C_EMPTY_BUFFER,
@@ -62,26 +63,102 @@ ssh_gssapi_mech gssapi_null_mech =
 
 #ifdef KRB5
 extern ssh_gssapi_mech gssapi_kerberos_mech;
-extern ssh_gssapi_mech gssapi_kerberos_mech_old;
 #endif
 #ifdef GSI
 extern ssh_gssapi_mech gssapi_gsi_mech;
-extern ssh_gssapi_mech gssapi_gsi_mech_old;
 #endif
 
 ssh_gssapi_mech* supported_mechs[]= {
 #ifdef KRB5
        &gssapi_kerberos_mech,
-       &gssapi_kerberos_mech_old, /* Support for legacy clients */
 #endif
 #ifdef GSI
        &gssapi_gsi_mech,
-       &gssapi_gsi_mech_old,   /* Support for legacy clients */
 #endif
        &gssapi_null_mech,
 };
 
-/* Unpriviledged */
+#ifdef GSS_C_GLOBUS_LIMITED_PROXY_FLAG
+static int limited = 0;
+#endif
+
+/* 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);
+}
+
+/*
+ * Acquire credentials for a server running on the current host.
+ * Requires that the context structure contains a valid OID
+ */
+
+/* Returns a GSSAPI error code */
+/* Privileged (called from ssh_gssapi_server_ctx) */
+static 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;
+}
+
+
+/* Privileged */
+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));
+}
+
+/* Unprivileged */
 void
 ssh_gssapi_supported_oids(gss_OID_set *oidset)
 {
@@ -91,7 +168,8 @@ ssh_gssapi_supported_oids(gss_OID_set *oidset)
        gss_OID_set supported;
 
        gss_create_empty_oid_set(&min_status, oidset);
-       gss_indicate_mechs(&min_status, &supported);
+       /* Ask priviledged process what mechanisms it supports. */
+       PRIVSEP(gss_indicate_mechs(&min_status, &supported));
 
        while (supported_mechs[i]->name != NULL) {
                if (GSS_ERROR(gss_test_oid_set_member(&min_status,
@@ -102,6 +180,8 @@ ssh_gssapi_supported_oids(gss_OID_set *oidset)
                            &supported_mechs[i]->oid, oidset);
                i++;
        }
+
+       gss_release_oid_set(&min_status, &supported);
 }
 
 
@@ -110,7 +190,7 @@ ssh_gssapi_supported_oids(gss_OID_set *oidset)
  *    oid
  *    credentials      (from ssh_gssapi_acquire_cred)
  */
-/* Priviledged */
+/* Privileged */
 OM_uint32
 ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *recv_tok,
     gss_buffer_desc *send_tok, OM_uint32 *flags)
@@ -141,6 +221,10 @@ ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *recv_tok,
            (*flags & GSS_C_INTEG_FLAG))) && (ctx->major == GSS_S_COMPLETE)) {
                if (ssh_gssapi_getclient(ctx, &gssapi_client))
                        fatal("Couldn't convert client name");
+#ifdef GSS_C_GLOBUS_LIMITED_PROXY_FLAG
+               if (flags && (*flags & GSS_C_GLOBUS_LIMITED_PROXY_FLAG))
+                       limited=1;
+#endif
        }
 
        return (status);
@@ -154,11 +238,11 @@ ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *recv_tok,
 static OM_uint32
 ssh_gssapi_parse_ename(Gssctxt *ctx, gss_buffer_t ename, gss_buffer_t name)
 {
-       char *tok;
+       u_char *tok;
        OM_uint32 offset;
        OM_uint32 oidl;
 
-       tok=ename->value;
+       tok = ename->value;
 
 #ifdef GSI /* GSI gss_export_name() is broken. */
        if ((ctx->oid->length == gssapi_gsi_mech.oid.length) &&
@@ -176,7 +260,7 @@ ssh_gssapi_parse_ename(Gssctxt *ctx, gss_buffer_t ename, gss_buffer_t name)
         * header, and that the initial ID bytes are correct
         */
 
-       if (ename->length<6 || memcmp(tok,"\x04\x01", 2)!=0)
+       if (ename->length < 6 || memcmp(tok, "\x04\x01", 2) != 0)
                return GSS_S_FAILURE;
 
        /*
@@ -186,7 +270,7 @@ ssh_gssapi_parse_ename(Gssctxt *ctx, gss_buffer_t ename, gss_buffer_t name)
         * second without.
         */
 
-       oidl = GET_16BIT(tok+2); /* length including next two bytes */
+       oidl = get_u16(tok+2); /* length including next two bytes */
        oidl = oidl-2; /* turn it into the _real_ length of the variable OID */
 
        /*
@@ -195,7 +279,7 @@ ssh_gssapi_parse_ename(Gssctxt *ctx, gss_buffer_t ename, gss_buffer_t name)
         */
        if (tok[4] != 0x06 || tok[5] != oidl ||
            ename->length < oidl+6 ||
-          !ssh_gssapi_check_oid(ctx,tok+6,oidl))
+           !ssh_gssapi_check_oid(ctx, tok+6, oidl))
                return GSS_S_FAILURE;
 
        offset = oidl+6;
@@ -203,14 +287,14 @@ ssh_gssapi_parse_ename(Gssctxt *ctx, gss_buffer_t ename, gss_buffer_t name)
        if (ename->length < offset+4)
                return GSS_S_FAILURE;
 
-       name->length = GET_32BIT(tok+offset);
+       name->length = get_u32(tok+offset);
        offset += 4;
 
        if (ename->length < offset+name->length)
                return GSS_S_FAILURE;
 
        name->value = xmalloc(name->length+1);
-       memcpy(name->value,tok+offset,name->length);
+       memcpy(name->value, tok+offset, name->length);
        ((char *)name->value)[name->length] = 0;
 
        return GSS_S_COMPLETE;
@@ -219,7 +303,7 @@ ssh_gssapi_parse_ename(Gssctxt *ctx, gss_buffer_t ename, gss_buffer_t name)
 /* Extract the client details from a given context. This can only reliably
  * be called once for a context */
 
-/* Priviledged (called from accept_secure_ctx) */
+/* Privileged (called from accept_secure_ctx) */
 OM_uint32
 ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
 {
@@ -260,6 +344,10 @@ ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
        /* We can't copy this structure, so we just move the pointer to it */
        client->creds = ctx->client_creds;
        ctx->client_creds = GSS_C_NO_CREDENTIAL;
+
+    /* needed for globus_gss_assist_map_and_authorize() */
+    client->context = ctx->context;
+
        return (ctx->major);
 }
 
@@ -269,7 +357,8 @@ ssh_gssapi_cleanup_creds(void)
 {
        if (gssapi_client.store.filename != NULL) {
                /* Unlink probably isn't sufficient */
-               debug("removing gssapi cred file\"%s\"", gssapi_client.store.filename);
+               debug("removing gssapi cred file\"%s\"",
+                   gssapi_client.store.filename);
                unlink(gssapi_client.store.filename);
        }
 }
@@ -279,6 +368,11 @@ void
 ssh_gssapi_storecreds(void)
 {
        if (gssapi_client.mech && gssapi_client.mech->storecreds) {
+        if (options.gss_creds_path) {
+            gssapi_client.store.filename =
+                expand_authorized_keys(options.gss_creds_path,
+                                       the_authctxt->pw);
+        }
                (*gssapi_client.mech->storecreds)(&gssapi_client);
        } else
                debug("ssh_gssapi_storecreds: Not a GSSAPI mechanism");
@@ -294,135 +388,48 @@ ssh_gssapi_do_child(char ***envp, u_int *envsizep)
 
        if (gssapi_client.store.envvar != NULL &&
            gssapi_client.store.envval != NULL) {
-
                debug("Setting %s to %s", gssapi_client.store.envvar,
-               gssapi_client.store.envval);
+                   gssapi_client.store.envval);
                child_set_env(envp, envsizep, gssapi_client.store.envvar,
-                    gssapi_client.store.envval);
+                   gssapi_client.store.envval);
        }
 }
 
-/* Priviledged */
+/* Privileged */
 int
 ssh_gssapi_userok(char *user)
 {
+       OM_uint32 lmin;
+
        if (gssapi_client.exportedname.length == 0 ||
            gssapi_client.exportedname.value == NULL) {
                debug("No suitable client data");
                return 0;
        }
+#ifdef GSS_C_GLOBUS_LIMITED_PROXY_FLAG
+       if (limited && options.gsi_allow_limited_proxy != 1) {
+               debug("limited proxy not acceptable for remote login");
+               return 0;
+       }
+#endif
        if (gssapi_client.mech && gssapi_client.mech->userok)
-               return ((*gssapi_client.mech->userok)(&gssapi_client, user));
+               if ((*gssapi_client.mech->userok)(&gssapi_client, user))
+                       return 1;
+               else {
+                       /* Destroy delegated credentials if userok fails */
+                       gss_release_buffer(&lmin, &gssapi_client.displayname);
+                       gss_release_buffer(&lmin, &gssapi_client.exportedname);
+                       gss_release_cred(&lmin, &gssapi_client.creds);
+                       memset(&gssapi_client, 0, sizeof(ssh_gssapi_client));
+                       return 0;
+               }
        else
                debug("ssh_gssapi_userok: Unknown GSSAPI mechanism");
        return (0);
 }
 
-/* Return a list of the gss-group1-sha1-x mechanisms supported by this
- * program.
- *
- * We only support the mechanisms that we've indicated in the list above,
- * but we check that they're supported by the GSSAPI mechanism on the 
- * machine. We also check, before including them in the list, that
- * we have the necesary information in order to carry out the key exchange
- * (that is, that the user has credentials, the server's creds are accessible,
- * etc)
- *
- * The way that this is done is fairly nasty, as we do a lot of work that
- * is then thrown away. This should possibly be implemented with a cache
- * that stores the results (in an expanded Gssctxt structure), which are
- * then used by the first calls if that key exchange mechanism is chosen.
- */
-
-/* Unpriviledged */ 
-char * 
-ssh_gssapi_server_mechanisms() {
-       gss_OID_set     supported;
-       Gssctxt         *ctx = NULL;
-       OM_uint32       maj_status, min_status;
-       Buffer          buf;
-       int             i = 0;
-       int             first = 0;
-       int             present;
-       char *          mechs;
-
-       if (datafellows & SSH_OLD_GSSAPI) return NULL;
-       
-       ssh_gssapi_supported_oids(&supported);
-       
-       buffer_init(&buf);
-
-       while(supported_mechs[i]->name != NULL) {
-               if ((maj_status=gss_test_oid_set_member(&min_status,
-                                                       &supported_mechs[i]->oid,
-                                                       supported,
-                                                       &present))) {
-                       present=0;
-               }
-
-               if (present) {
-                   if (!GSS_ERROR(PRIVSEP(ssh_gssapi_server_ctx(&ctx,
-                                          &supported_mechs[i]->oid)))) {
-                       /* Append gss_group1_sha1_x to our list */
-                       if (first++!=0)
-                               buffer_put_char(&buf,',');
-                       buffer_append(&buf, KEX_GSS_SHA1,
-                                     sizeof(KEX_GSS_SHA1)-1);
-                       buffer_append(&buf, 
-                                     supported_mechs[i]->enc_name,
-                                     strlen(supported_mechs[i]->enc_name));
-                       debug("GSSAPI mechanism %s (%s%s) supported",
-                             supported_mechs[i]->name, KEX_GSS_SHA1,
-                             supported_mechs[i]->enc_name);
-                   } else {
-                       debug("no credentials for GSSAPI mechanism %s",
-                             supported_mechs[i]->name);
-                   }
-               } else {
-                   debug("GSSAPI mechanism %s not supported",
-                         supported_mechs[i]->name);
-               }
-               ssh_gssapi_delete_ctx(&ctx);
-               i++;
-       }
-       
-       buffer_put_char(&buf,'\0');
-       
-       mechs=xmalloc(buffer_len(&buf));
-       buffer_get(&buf,mechs,buffer_len(&buf));
-       buffer_free(&buf);
-       if (strlen(mechs)==0)
-          return(NULL);
-       else
-          return(mechs);
-}
-
-/* Return the OID that corresponds to the given context name */
-/* Unpriviledged */
-gss_OID 
-ssh_gssapi_server_id_kex(char *name) {
-  int i=0;
-  
-  if (strncmp(name, KEX_GSS_SHA1, sizeof(KEX_GSS_SHA1)-1) !=0) {
-     return(NULL);
-  }
-  
-  name+=sizeof(KEX_GSS_SHA1)-1; /* Move to the start of the MIME string */
-  
-  while (supported_mechs[i]->name!=NULL &&
-        strcmp(name,supported_mechs[i]->enc_name)!=0) {
-       i++;
-  }
-
-  if (supported_mechs[i]->name==NULL)
-     return (NULL);
-
-  debug("using GSSAPI mechanism %s (%s%s)", supported_mechs[i]->name,
-       KEX_GSS_SHA1, supported_mechs[i]->enc_name);
-
-  return &supported_mechs[i]->oid;
-}
+/* ssh_gssapi_checkmic() moved to gss-genr.c so it can be called by
+   kexgss_client(). */
 
 /* Priviledged */
 int
@@ -442,14 +449,4 @@ ssh_gssapi_localname(char **user)
        return(0);
 }
 
-/* Priviledged */
-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
This page took 0.131175 seconds and 4 git commands to generate.