Here's a revised patch that cleans up a few of the issues you mentioned. You may want to omit the USE_KEYTAB patch to passdb/secrets.c: we don't actually use that, and without support for updating the secret, it may be of limited use.
-- Luke
Index: configure.in =================================================================== RCS file: /cvsroot/samba/source/configure.in,v retrieving revision 1.409 diff -u -r1.409 configure.in --- configure.in 22 Feb 2003 12:19:18 -0000 1.409 +++ configure.in 24 Feb 2003 06:04:25 -0000 @@ -627,6 +627,15 @@ fi ############################################ +# support for using Kerberos keytab instead of secrets database + +AC_ARG_ENABLE(keytab, +[ --enable-keytab Turn on support for Kerberos keytabs in lieu of secrets DB (default=no)], + [if eval "test x$enable_keytab = xyes"; then + AC_DEFINE(USE_KEYTAB,1,[Use Kerberos keytab]) + fi]) + +############################################ # we need dlopen/dlclose/dlsym/dlerror for PAM, the password database plugins and the plugin loading code AC_SEARCH_LIBS(dlopen, [dl]) # dlopen/dlclose/dlsym/dlerror will be checked again later and defines will be set then @@ -2248,6 +2257,22 @@ samba_cv_HAVE_KRB5_TKT_ENC_PART2=yes,samba_cv_HAVE_KRB5_TKT_ENC_PART2=no)]) if test x"$samba_cv_HAVE_KRB5_TKT_ENC_PART2" = x"yes"; then AC_DEFINE(HAVE_KRB5_TKT_ENC_PART2,1,[Whether the krb5_ticket struct has a enc_part2 property]) +fi + +AC_CACHE_CHECK([for keyvalue in krb5_keyblock],samba_cv_HAVE_KRB5_KEYBLOCK_KEYVALUE,[ +AC_TRY_COMPILE([#include <krb5.h>], +[krb5_keyblock key; key.keyvalue.data = NULL;], +samba_cv_HAVE_KRB5_KEYBLOCK_KEYVALUE=yes,samba_cv_HAVE_KRB5_KEYBLOCK_KEYVALUE=no)]) +if test x"$samba_cv_HAVE_KRB5_KEYBLOCK_KEYVALUE" = x"yes"; then + AC_DEFINE(HAVE_KRB5_KEYBLOCK_KEYVALUE,1,[Whether the krb5_keyblock struct has a keyvalue property]) +fi + +AC_CACHE_CHECK([for ENCTYPE_ARCFOUR_HMAC_MD5],samba_cv_HAVE_ENCTYPE_ARCFOUR_HMAC_MD5,[ +AC_TRY_COMPILE([#include <krb5.h>], +[krb5_enctype enctype; enctype = ENCTYPE_ARCFOUR_HMAC_MD5;], +samba_cv_HAVE_ENCTYPE_ARCFOUR_HMAC_MD5=yes,samba_cv_HAVE_ENCTYPE_ARCFOUR_HMAC_MD5=no)]) +if test x"$samba_cv_HAVE_ENCTYPE_ARCFOUR_HMAC_MD5" = x"yes"; then + AC_DEFINE(HAVE_ENCTYPE_ARCFOUR_HMAC_MD5,1,[Whether the ENCTYPE_ARCFOUR_HMAC_MD5 key type is available]) fi ######################################################## Index: include/asn_1.h =================================================================== RCS file: /cvsroot/samba/source/include/asn_1.h,v retrieving revision 1.6 diff -u -r1.6 asn_1.h --- include/asn_1.h 13 Feb 2003 21:40:35 -0000 1.6 +++ include/asn_1.h 24 Feb 2003 06:04:26 -0000 @@ -59,4 +59,11 @@ #define SPNEGO_NEG_RESULT_INCOMPLETE 1 #define SPNEGO_NEG_RESULT_REJECT 2 +/* not really ASN.1, but RFC 1964 */ +#define TOK_ID_KRB_AP_REQ "\x01\x00" +#define TOK_ID_KRB_AP_REP "\x02\x00" +#define TOK_ID_KRB_ERROR "\x03\x00" +#define TOK_ID_GSS_GETMIC "\x01\x01" +#define TOK_ID_GSS_WRAP "\x02\x01" + #endif /* _ASN_1_H */ Index: libads/kerberos_verify.c =================================================================== RCS file: /cvsroot/samba/source/libads/kerberos_verify.c,v retrieving revision 1.6 diff -u -r1.6 kerberos_verify.c --- libads/kerberos_verify.c 19 Feb 2003 01:16:40 -0000 1.6 +++ libads/kerberos_verify.c 24 Feb 2003 06:04:26 -0000 @@ -3,7 +3,7 @@ kerberos utility library Copyright (C) Andrew Tridgell 2001 Copyright (C) Remus Koos 2001 - + Copyright (C) Luke Howard 2003 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -29,14 +29,18 @@ authorization_data if available */ NTSTATUS ads_verify_ticket(ADS_STRUCT *ads, const DATA_BLOB *ticket, - char **principal, DATA_BLOB *auth_data) + char **principal, DATA_BLOB *auth_data, + DATA_BLOB *ap_rep, + uint8 session_key[16]) { krb5_context context; krb5_auth_context auth_context = NULL; krb5_keytab keytab = NULL; krb5_data packet; krb5_ticket *tkt = NULL; - int ret, i; + int ret; +#ifndef USE_KEYTAB + int i; krb5_keyblock * key; krb5_principal host_princ; char *host_princ_s; @@ -44,8 +48,10 @@ char *password_s; krb5_data password; krb5_enctype *enctypes = NULL; +#endif /* USE_KEYTAB */ BOOL auth_ok = False; +#ifndef USE_KEYTAB if (!secrets_init()) { DEBUG(1,("secrets_init failed\n")); return NT_STATUS_LOGON_FAILURE; @@ -59,6 +65,7 @@ password.data = password_s; password.length = strlen(password_s); +#endif /* USE_KEYTAB */ ret = krb5_init_context(&context); if (ret) { @@ -81,6 +88,16 @@ return NT_STATUS_LOGON_FAILURE; } +#ifdef USE_KEYTAB + packet.length = ticket->length; + packet.data = (krb5_pointer)ticket->data; + + if (!(ret = krb5_rd_req(context, &auth_context, &packet, + NULL, keytab, NULL, &tkt))) { + auth_ok = True; + } + +#else fstrcpy(myname, global_myname()); strlower(myname); asprintf(&host_princ_s, "HOST/[EMAIL PROTECTED]", myname, lp_realm()); @@ -119,13 +136,30 @@ } } + SAFE_FREE(key); +#endif /* USE_KEYTAB */ + if (!auth_ok) { DEBUG(3,("krb5_rd_req with auth failed (%s)\n", error_message(ret))); - SAFE_FREE(key); return NT_STATUS_LOGON_FAILURE; } + ret = krb5_mk_rep(context, auth_context, &packet); + if (ret) { + DEBUG(3,("Failed to generate mutual authentication reply (%s)\n", + error_message(ret))); + krb5_auth_con_free(context, auth_context); + return NT_STATUS_LOGON_FAILURE; + } + + *ap_rep = data_blob(packet.data, packet.length); + free(packet.data); + + krb5_get_smb_session_key(context, auth_context, session_key); + DEBUG(0,("SMB session key (from ticket) follows:\n")); + dump_data(0, session_key, 16); + #if 0 file_save("/tmp/ticket.dat", ticket->data, ticket->length); #endif @@ -134,20 +168,24 @@ #if 0 if (tkt->enc_part2) { - file_save("/tmp/authdata.dat", + file_save("/tmp/authdata.dat", tkt->enc_part2->authorization_data[0]->contents, tkt->enc_part2->authorization_data[0]->length); - } #endif if ((ret = krb5_unparse_name(context, get_principal_from_tkt(tkt), principal))) { DEBUG(3,("krb5_unparse_name failed (%s)\n", error_message(ret))); + data_blob_free(auth_data); + data_blob_free(ap_rep); + krb5_auth_con_free(context, auth_context); return NT_STATUS_LOGON_FAILURE; } + krb5_auth_con_free(context, auth_context); + return NT_STATUS_OK; } -#endif +#endif /* HAVE_KRB5 */ Index: libsmb/clikrb5.c =================================================================== RCS file: /cvsroot/samba/source/libsmb/clikrb5.c,v retrieving revision 1.33 diff -u -r1.33 clikrb5.c --- libsmb/clikrb5.c 21 Feb 2003 14:35:02 -0000 1.33 +++ libsmb/clikrb5.c 24 Feb 2003 06:04:26 -0000 @@ -2,7 +2,7 @@ Unix SMB/CIFS implementation. simple kerberos5 routines for active directory Copyright (C) Andrew Tridgell 2001 - Copyright (C) Luke Howard 2002 + Copyright (C) Luke Howard 2002-2003 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -23,6 +23,16 @@ #ifdef HAVE_KRB5 +#ifdef HAVE_KRB5_KEYBLOCK_KEYVALUE +#define KRB5_KEY_TYPE(k) ((k)->keytype) +#define KRB5_KEY_LENGTH(k) ((k)->keyvalue.length) +#define KRB5_KEY_DATA(k) ((k)->keyvalue.data) +#else +#define KRB5_KEY_TYPE(k) ((k)->enctype) +#define KRB5_KEY_LENGTH(k) ((k)->length) +#define KRB5_KEY_DATA(k) ((k)->contents) +#endif /* HAVE_KRB5_KEYBLOCK_KEYVALUE */ + #ifndef HAVE_KRB5_SET_REAL_TIME /* * This function is not in the Heimdal mainline. @@ -305,8 +315,10 @@ DATA_BLOB ret; krb5_enctype enc_types[] = { #ifdef ENCTYPE_ARCFOUR_HMAC - ENCTYPE_ARCFOUR_HMAC, -#endif + ENCTYPE_ARCFOUR_HMAC, +#elif defined(HAVE_ENCTYPE_ARCFOUR_HMAC_MD5) + ENCTYPE_ARCFOUR_HMAC_MD5, +#endif ENCTYPE_DES_CBC_MD5, ENCTYPE_DES_CBC_CRC, ENCTYPE_NULL}; @@ -355,11 +367,43 @@ return data_blob(NULL, 0); } + BOOL krb5_get_smb_session_key(krb5_context context, krb5_auth_context auth_context, uint8 session_key[16]) + { + krb5_keyblock *skey; + BOOL ret = False; + + memset(session_key, 0, 16); + +#if defined(ENCTYPE_ARCFOUR_HMAC) || defined(HAVE_ENCTYPE_ARCFOUR_HMAC_MD5) + if (krb5_auth_con_getremotesubkey(context, auth_context, &skey) == 0 && skey != NULL) { + if (KRB5_KEY_TYPE(skey) == +# ifdef ENCTYPE_ARCFOUR_HMAC + ENCTYPE_ARCFOUR_HMAC +# else + ENCTYPE_ARCFOUR_HMAC_MD5 +# endif /* ENCTYPE_ARCFOUR_HMAC */ + && KRB5_KEY_LENGTH(skey) == 16) { + memcpy(session_key, KRB5_KEY_DATA(skey), KRB5_KEY_LENGTH(skey)); + ret = True; + } + krb5_free_keyblock(context, skey); + } +#endif /* ENCTYPE_ARCFOUR_HMAC || HAVE_ENCTYPE_ARCFOUR_HMAC_MD5 */ + + return ret; + } #else /* HAVE_KRB5 */ /* this saves a few linking headaches */ DATA_BLOB krb5_get_ticket(const char *principal, time_t time_offset) { DEBUG(0,("NO KERBEROS SUPPORT\n")); return data_blob(NULL, 0); + } + + BOOL krb5_get_smb_session_key(krb5_context context, krb5_auth_context ac, uint8 session_key[16]) + { + DEBUG(0,("NO KERBEROS SUPPORT\n")); + memset(session_key, 0, 16); + return False; } #endif Index: libsmb/clispnego.c =================================================================== RCS file: /cvsroot/samba/source/libsmb/clispnego.c,v retrieving revision 1.28 diff -u -r1.28 clispnego.c --- libsmb/clispnego.c 15 Feb 2003 12:20:22 -0000 1.28 +++ libsmb/clispnego.c 24 Feb 2003 06:04:26 -0000 @@ -3,6 +3,7 @@ simple kerberos5/SPNEGO routines Copyright (C) Andrew Tridgell 2001 Copyright (C) Jim McDonough 2002 + Copyright (C) Luke Howard 2003 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -259,7 +260,7 @@ /* generate a krb5 GSS-API wrapper packet given a ticket */ -DATA_BLOB spnego_gen_krb5_wrap(DATA_BLOB ticket) +DATA_BLOB spnego_gen_krb5_wrap(DATA_BLOB ticket, uint8 tok_id[2]) { ASN1_DATA data; DATA_BLOB ret; @@ -268,7 +269,8 @@ asn1_push_tag(&data, ASN1_APPLICATION(0)); asn1_write_OID(&data, OID_KERBEROS5); - asn1_write_BOOLEAN(&data, 0); + + asn1_write(&data, tok_id, 2); asn1_write(&data, ticket.data, ticket.length); asn1_pop_tag(&data); @@ -286,7 +288,7 @@ /* parse a krb5 GSS-API wrapper packet giving a ticket */ -BOOL spnego_parse_krb5_wrap(DATA_BLOB blob, DATA_BLOB *ticket) +BOOL spnego_parse_krb5_wrap(DATA_BLOB blob, DATA_BLOB *ticket, uint8 tok_id[2]) { BOOL ret; ASN1_DATA data; @@ -295,15 +297,15 @@ asn1_load(&data, blob); asn1_start_tag(&data, ASN1_APPLICATION(0)); asn1_check_OID(&data, OID_KERBEROS5); - asn1_check_BOOLEAN(&data, 0); data_remaining = asn1_tag_remaining(&data); - if (data_remaining < 1) { + if (data_remaining < 3) { data.has_error = True; } else { - - *ticket = data_blob(data.data, data_remaining); + asn1_read(&data, tok_id, 2); + data_remaining -= 2; + *ticket = data_blob(NULL, data_remaining); asn1_read(&data, ticket->data, ticket->length); } @@ -330,7 +332,7 @@ tkt = krb5_get_ticket(principal, time_offset); /* wrap that up in a nice GSS-API wrapping */ - tkt_wrapped = spnego_gen_krb5_wrap(tkt); + tkt_wrapped = spnego_gen_krb5_wrap(tkt, TOK_ID_KRB_AP_REQ); /* and wrap that in a shiny SPNEGO wrapper */ targ = gen_negTokenTarg(krb_mechs, tkt_wrapped); @@ -438,9 +440,10 @@ } /* - generate a minimal SPNEGO NTLMSSP response packet. Doesn't contain much. + generate a minimal SPNEGO response packet. Doesn't contain much. */ -DATA_BLOB spnego_gen_auth_response(DATA_BLOB *ntlmssp_reply, NTSTATUS nt_status) +DATA_BLOB spnego_gen_auth_response(DATA_BLOB *reply, NTSTATUS nt_status, + const char *mechOID) { ASN1_DATA data; DATA_BLOB ret; @@ -462,13 +465,13 @@ asn1_write_enumerated(&data, negResult); asn1_pop_tag(&data); - if (negResult == SPNEGO_NEG_RESULT_INCOMPLETE) { + if (reply->data != NULL) { asn1_push_tag(&data,ASN1_CONTEXT(1)); - asn1_write_OID(&data, OID_NTLMSSP); + asn1_write_OID(&data, mechOID); asn1_pop_tag(&data); asn1_push_tag(&data,ASN1_CONTEXT(2)); - asn1_write_OctetString(&data, ntlmssp_reply->data, ntlmssp_reply->length); + asn1_write_OctetString(&data, reply->data, reply->length); asn1_pop_tag(&data); } Index: passdb/secrets.c =================================================================== RCS file: /cvsroot/samba/source/passdb/secrets.c,v retrieving revision 1.54 diff -u -r1.54 secrets.c --- passdb/secrets.c 1 Feb 2003 04:39:15 -0000 1.54 +++ passdb/secrets.c 24 Feb 2003 06:04:26 -0000 @@ -221,6 +221,72 @@ return True; } +#ifdef USE_KEYTAB +/************************************************************************ + Read local secret from the keytab +************************************************************************/ + +static BOOL secrets_fetch_keytab_password(uint8 ret_pwd[16], time_t *pass_last_set_time) +{ + char spn[MAXHOSTNAMELEN + 2], *p; + krb5_context context; + krb5_error_code ret; + krb5_principal princ; + krb5_keyblock *key; + + ret = krb5_init_context(&context); + if (ret) { + DEBUG(1, ("secrets_fetch_keytab_password: failed to initialize Kerberos context\n")); + return False; + } + + spn[sizeof(spn) - 1] = '\0'; + if (gethostname(spn, sizeof(spn) - 2) < 0) { + DEBUG(1, ("secrets_fetch_keytab_password: could not determine local hostname\n")); + krb5_free_context(context); + return False; + } + + for (p = spn; *p && *p != '.'; p++) + *p = toupper(*p); + *p++ = '$'; + *p = '\0'; + + ret = krb5_parse_name(context, spn, &princ); + if (ret) { + DEBUG(1, ("secrets_fetch_keytab_password: failed to parse name %s\n", spn)); + krb5_free_context(context); + return False; + } + +#ifdef ENCTYPE_ARCFOUR_HMAC + ret = krb5_kt_read_service_key(context, NULL, princ, 0, ENCTYPE_ARCFOUR_HMAC, &key); +#elif defined(HAVE_ENCTYPE_ARCFOUR_HMAC_MD5) + ret = krb5_kt_read_service_key(context, NULL, princ, 0, ENCTYPE_ARCFOUR_HMAC_MD5, &key); +#else +#error ENCTYPE_ARCFOUR_HMAC or ENCTYPE_ARCFOUR_HMAC_MD5 required for keytab secret storage +#endif + if (ret) { + DEBUG(1, ("secrets_fetch_keytab_password: failed to read secret for %s\n", spn)); + krb5_free_context(context); + return False; + } + if (key->keyvalue.length != 16) { + DEBUG(1, ("secrets_fetch_keytab_password: key is incorrect length\n")); + krb5_free_context(context); + return False; + } + + memcpy(ret_pwd, key->keyvalue.data, key->keyvalue.length); + time(pass_last_set_time); /* XXX */ + + krb5_free_keyblock(context, key); + krb5_free_context(context); + + return True; +} +#endif /* USE_KEYTAB */ + /************************************************************************ Routine to get the trust account password for a domain. The user of this function must have locked the trust password file using @@ -243,6 +309,12 @@ pass_last_set_time = 0; return True; } + +#ifdef USE_KEYTAB + if (is_myworkgroup(domain)) { + return secrets_fetch_keytab_password(ret_pwd, pass_last_set_time); + } +#endif /* USE_KEYTAB */ if (!(pass = secrets_fetch(trust_keystr(domain), &size))) { DEBUG(5, ("secrets_fetch failed!\n")); Index: smbd/sesssetup.c =================================================================== RCS file: /cvsroot/samba/source/smbd/sesssetup.c,v retrieving revision 1.89 diff -u -r1.89 sesssetup.c --- smbd/sesssetup.c 21 Feb 2003 04:46:27 -0000 1.89 +++ smbd/sesssetup.c 24 Feb 2003 06:04:27 -0000 @@ -4,6 +4,7 @@ Copyright (C) Andrew Tridgell 1998-2001 Copyright (C) Andrew Bartlett 2001 Copyright (C) Jim McDonough 2002 + Copyright (C) Luke Howard 2003 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -146,11 +147,14 @@ int sess_vuid; NTSTATUS ret; DATA_BLOB auth_data; + DATA_BLOB ap_rep, ap_rep_wrapped, response; auth_serversupplied_info *server_info = NULL; ADS_STRUCT *ads; + uint8 session_key[16]; + uint8 tok_id[2]; BOOL foreign = False; - if (!spnego_parse_krb5_wrap(*secblob, &ticket)) { + if (!spnego_parse_krb5_wrap(*secblob, &ticket, tok_id)) { return ERROR_NT(NT_STATUS_LOGON_FAILURE); } @@ -162,7 +166,7 @@ ads->auth.realm = strdup(lp_realm()); - ret = ads_verify_ticket(ads, &ticket, &client, &auth_data); + ret = ads_verify_ticket(ads, &ticket, &client, &auth_data, &ap_rep, session_key); if (!NT_STATUS_IS_OK(ret)) { DEBUG(1,("Failed to verify incoming ticket!\n")); ads_destroy(&ads); @@ -177,6 +181,7 @@ if (!p) { DEBUG(3,("Doesn't look like a valid principal\n")); ads_destroy(&ads); + data_blob_free(&ap_rep); return ERROR_NT(NT_STATUS_LOGON_FAILURE); } @@ -184,6 +189,7 @@ if (strcasecmp(p+1, ads->auth.realm) != 0) { DEBUG(3,("Ticket for foreign realm [EMAIL PROTECTED]", client, p+1)); if (!lp_allow_trusted_domains()) { + data_blob_free(&ap_rep); return ERROR_NT(NT_STATUS_LOGON_FAILURE); } foreign = True; @@ -209,31 +215,51 @@ if (!pw) { DEBUG(1,("Username %s is invalid on this system\n",user)); + data_blob_free(&ap_rep); return ERROR_NT(NT_STATUS_NO_SUCH_USER); } if (!NT_STATUS_IS_OK(ret = make_server_info_pw(&server_info,pw))) { DEBUG(1,("make_server_info_from_pw failed!\n")); + data_blob_free(&ap_rep); return ERROR_NT(ret); } - + + /* Copy out the session key from the AP_REQ. */ + memcpy(server_info->session_key, session_key, sizeof(session_key)); + /* register_vuid keeps the server info */ sess_vuid = register_vuid(server_info, user); free(user); if (sess_vuid == -1) { - return ERROR_NT(NT_STATUS_LOGON_FAILURE); + ret = NT_STATUS_LOGON_FAILURE; + } else { + set_message(outbuf,4,0,True); + SSVAL(outbuf, smb_vwv3, 0); + + if (server_info->guest) { + SSVAL(outbuf,smb_vwv2,1); + } + + SSVAL(outbuf, smb_uid, sess_vuid); } - set_message(outbuf,4,0,True); - SSVAL(outbuf, smb_vwv3, 0); - add_signature(outbuf); - - SSVAL(outbuf,smb_uid,sess_vuid); - SSVAL(inbuf,smb_uid,sess_vuid); - - return chain_reply(inbuf,outbuf,length,bufsize); + /* wrap that up in a nice GSS-API wrapping */ + if (NT_STATUS_IS_OK(ret)) { + ap_rep_wrapped = spnego_gen_krb5_wrap(ap_rep, TOK_ID_KRB_AP_REP); + } else { + ap_rep_wrapped = data_blob(NULL, 0); + } + response = spnego_gen_auth_response(&ap_rep_wrapped, ret, OID_KERBEROS5_OLD); + reply_sesssetup_blob(conn, outbuf, response, ret); + + data_blob_free(&ap_rep); + data_blob_free(&ap_rep_wrapped); + data_blob_free(&response); + + return -1; /* already replied */ } #endif @@ -280,7 +306,7 @@ } } - response = spnego_gen_auth_response(ntlmssp_blob, nt_status); + response = spnego_gen_auth_response(ntlmssp_blob, nt_status, OID_NTLMSSP); ret = reply_sesssetup_blob(conn, outbuf, response, nt_status); data_blob_free(&response);
-- Luke Howard | PADL Software Pty Ltd | www.padl.com