diff options
Diffstat (limited to 'source3/libsmb/clispnego.c')
| -rw-r--r-- | source3/libsmb/clispnego.c | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/source3/libsmb/clispnego.c b/source3/libsmb/clispnego.c new file mode 100644 index 0000000000..fa9dba098f --- /dev/null +++ b/source3/libsmb/clispnego.c @@ -0,0 +1,600 @@ +/* + Unix SMB/CIFS implementation. + simple kerberos5/SPNEGO routines + Copyright (C) Andrew Tridgell 2001 + Copyright (C) Jim McDonough <jmcd@us.ibm.com> 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 + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "includes.h" + +/* + generate a negTokenInit packet given a GUID, a list of supported + OIDs (the mechanisms) and a principal name string +*/ +DATA_BLOB spnego_gen_negTokenInit(char guid[16], + const char *OIDs[], + const char *principal) +{ + int i; + ASN1_DATA data; + DATA_BLOB ret; + + memset(&data, 0, sizeof(data)); + + asn1_write(&data, guid, 16); + asn1_push_tag(&data,ASN1_APPLICATION(0)); + asn1_write_OID(&data,OID_SPNEGO); + asn1_push_tag(&data,ASN1_CONTEXT(0)); + asn1_push_tag(&data,ASN1_SEQUENCE(0)); + + asn1_push_tag(&data,ASN1_CONTEXT(0)); + asn1_push_tag(&data,ASN1_SEQUENCE(0)); + for (i=0; OIDs[i]; i++) { + asn1_write_OID(&data,OIDs[i]); + } + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + asn1_push_tag(&data, ASN1_CONTEXT(3)); + asn1_push_tag(&data, ASN1_SEQUENCE(0)); + asn1_push_tag(&data, ASN1_CONTEXT(0)); + asn1_write_GeneralString(&data,principal); + asn1_pop_tag(&data); + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + asn1_pop_tag(&data); + + if (data.has_error) { + DEBUG(1,("Failed to build negTokenInit at offset %d\n", (int)data.ofs)); + asn1_free(&data); + } + + ret = data_blob(data.data, data.length); + asn1_free(&data); + + return ret; +} + +/* + Generate a negTokenInit as used by the client side ... It has a mechType + (OID), and a mechToken (a security blob) ... + + Really, we need to break out the NTLMSSP stuff as well, because it could be + raw in the packets! +*/ +DATA_BLOB gen_negTokenInit(const char *OID, DATA_BLOB blob) +{ + ASN1_DATA data; + DATA_BLOB ret; + + memset(&data, 0, sizeof(data)); + + asn1_push_tag(&data, ASN1_APPLICATION(0)); + asn1_write_OID(&data,OID_SPNEGO); + asn1_push_tag(&data, ASN1_CONTEXT(0)); + asn1_push_tag(&data, ASN1_SEQUENCE(0)); + + asn1_push_tag(&data, ASN1_CONTEXT(0)); + asn1_push_tag(&data, ASN1_SEQUENCE(0)); + asn1_write_OID(&data, OID); + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + asn1_push_tag(&data, ASN1_CONTEXT(2)); + asn1_write_OctetString(&data,blob.data,blob.length); + asn1_pop_tag(&data); + + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + asn1_pop_tag(&data); + + if (data.has_error) { + DEBUG(1,("Failed to build negTokenInit at offset %d\n", (int)data.ofs)); + asn1_free(&data); + } + + ret = data_blob(data.data, data.length); + asn1_free(&data); + + return ret; +} + +/* + parse a negTokenInit packet giving a GUID, a list of supported + OIDs (the mechanisms) and a principal name string +*/ +bool spnego_parse_negTokenInit(DATA_BLOB blob, + char *OIDs[ASN1_MAX_OIDS], + char **principal) +{ + int i; + bool ret; + ASN1_DATA data; + + asn1_load(&data, blob); + + asn1_start_tag(&data,ASN1_APPLICATION(0)); + asn1_check_OID(&data,OID_SPNEGO); + asn1_start_tag(&data,ASN1_CONTEXT(0)); + asn1_start_tag(&data,ASN1_SEQUENCE(0)); + + asn1_start_tag(&data,ASN1_CONTEXT(0)); + asn1_start_tag(&data,ASN1_SEQUENCE(0)); + for (i=0; asn1_tag_remaining(&data) > 0 && i < ASN1_MAX_OIDS-1; i++) { + char *oid_str = NULL; + asn1_read_OID(&data,&oid_str); + OIDs[i] = oid_str; + } + OIDs[i] = NULL; + asn1_end_tag(&data); + asn1_end_tag(&data); + + *principal = NULL; + if (asn1_tag_remaining(&data) > 0) { + asn1_start_tag(&data, ASN1_CONTEXT(3)); + asn1_start_tag(&data, ASN1_SEQUENCE(0)); + asn1_start_tag(&data, ASN1_CONTEXT(0)); + asn1_read_GeneralString(&data,principal); + asn1_end_tag(&data); + asn1_end_tag(&data); + asn1_end_tag(&data); + } + + asn1_end_tag(&data); + asn1_end_tag(&data); + + asn1_end_tag(&data); + + ret = !data.has_error; + if (data.has_error) { + int j; + SAFE_FREE(*principal); + for(j = 0; j < i && j < ASN1_MAX_OIDS-1; j++) { + SAFE_FREE(OIDs[j]); + } + } + + asn1_free(&data); + return ret; +} + +/* + generate a negTokenTarg packet given a list of OIDs and a security blob +*/ +DATA_BLOB gen_negTokenTarg(const char *OIDs[], DATA_BLOB blob) +{ + int i; + ASN1_DATA data; + DATA_BLOB ret; + + memset(&data, 0, sizeof(data)); + + asn1_push_tag(&data, ASN1_APPLICATION(0)); + asn1_write_OID(&data,OID_SPNEGO); + asn1_push_tag(&data, ASN1_CONTEXT(0)); + asn1_push_tag(&data, ASN1_SEQUENCE(0)); + + asn1_push_tag(&data, ASN1_CONTEXT(0)); + asn1_push_tag(&data, ASN1_SEQUENCE(0)); + for (i=0; OIDs[i]; i++) { + asn1_write_OID(&data,OIDs[i]); + } + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + asn1_push_tag(&data, ASN1_CONTEXT(2)); + asn1_write_OctetString(&data,blob.data,blob.length); + asn1_pop_tag(&data); + + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + asn1_pop_tag(&data); + + if (data.has_error) { + DEBUG(1,("Failed to build negTokenTarg at offset %d\n", (int)data.ofs)); + asn1_free(&data); + } + + ret = data_blob(data.data, data.length); + asn1_free(&data); + + return ret; +} + +/* + parse a negTokenTarg packet giving a list of OIDs and a security blob +*/ +bool parse_negTokenTarg(DATA_BLOB blob, char *OIDs[ASN1_MAX_OIDS], DATA_BLOB *secblob) +{ + int i; + ASN1_DATA data; + + asn1_load(&data, blob); + asn1_start_tag(&data, ASN1_APPLICATION(0)); + asn1_check_OID(&data,OID_SPNEGO); + asn1_start_tag(&data, ASN1_CONTEXT(0)); + asn1_start_tag(&data, ASN1_SEQUENCE(0)); + + asn1_start_tag(&data, ASN1_CONTEXT(0)); + asn1_start_tag(&data, ASN1_SEQUENCE(0)); + for (i=0; asn1_tag_remaining(&data) > 0 && i < ASN1_MAX_OIDS-1; i++) { + char *oid_str = NULL; + asn1_read_OID(&data,&oid_str); + OIDs[i] = oid_str; + } + OIDs[i] = NULL; + asn1_end_tag(&data); + asn1_end_tag(&data); + + /* Skip any optional req_flags that are sent per RFC 4178 */ + if (asn1_check_tag(&data, ASN1_CONTEXT(1))) { + uint8 flags; + + asn1_start_tag(&data, ASN1_CONTEXT(1)); + asn1_start_tag(&data, ASN1_BITFIELD); + while (asn1_tag_remaining(&data) > 0) + asn1_read_uint8(&data, &flags); + asn1_end_tag(&data); + asn1_end_tag(&data); + } + + asn1_start_tag(&data, ASN1_CONTEXT(2)); + asn1_read_OctetString(&data,secblob); + asn1_end_tag(&data); + + asn1_end_tag(&data); + asn1_end_tag(&data); + + asn1_end_tag(&data); + + if (data.has_error) { + int j; + data_blob_free(secblob); + for(j = 0; j < i && j < ASN1_MAX_OIDS-1; j++) { + SAFE_FREE(OIDs[j]); + } + DEBUG(1,("Failed to parse negTokenTarg at offset %d\n", (int)data.ofs)); + asn1_free(&data); + return False; + } + + asn1_free(&data); + return True; +} + +/* + generate a krb5 GSS-API wrapper packet given a ticket +*/ +DATA_BLOB spnego_gen_krb5_wrap(const DATA_BLOB ticket, const uint8 tok_id[2]) +{ + ASN1_DATA data; + DATA_BLOB ret; + + memset(&data, 0, sizeof(data)); + + asn1_push_tag(&data, ASN1_APPLICATION(0)); + asn1_write_OID(&data, OID_KERBEROS5); + + asn1_write(&data, tok_id, 2); + asn1_write(&data, ticket.data, ticket.length); + asn1_pop_tag(&data); + + if (data.has_error) { + DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data.ofs)); + asn1_free(&data); + } + + ret = data_blob(data.data, data.length); + asn1_free(&data); + + return ret; +} + +/* + parse a krb5 GSS-API wrapper packet giving a ticket +*/ +bool spnego_parse_krb5_wrap(DATA_BLOB blob, DATA_BLOB *ticket, uint8 tok_id[2]) +{ + bool ret; + ASN1_DATA data; + int data_remaining; + + asn1_load(&data, blob); + asn1_start_tag(&data, ASN1_APPLICATION(0)); + asn1_check_OID(&data, OID_KERBEROS5); + + data_remaining = asn1_tag_remaining(&data); + + if (data_remaining < 3) { + data.has_error = True; + } else { + asn1_read(&data, tok_id, 2); + data_remaining -= 2; + *ticket = data_blob(NULL, data_remaining); + asn1_read(&data, ticket->data, ticket->length); + } + + asn1_end_tag(&data); + + ret = !data.has_error; + + if (data.has_error) { + data_blob_free(ticket); + } + + asn1_free(&data); + + return ret; +} + + +/* + generate a SPNEGO negTokenTarg packet, ready for a EXTENDED_SECURITY + kerberos session setup +*/ +int spnego_gen_negTokenTarg(const char *principal, int time_offset, + DATA_BLOB *targ, + DATA_BLOB *session_key_krb5, uint32 extra_ap_opts, + time_t *expire_time) +{ + int retval; + DATA_BLOB tkt, tkt_wrapped; + const char *krb_mechs[] = {OID_KERBEROS5_OLD, OID_KERBEROS5, OID_NTLMSSP, NULL}; + + /* get a kerberos ticket for the service and extract the session key */ + retval = cli_krb5_get_ticket(principal, time_offset, + &tkt, session_key_krb5, extra_ap_opts, NULL, + expire_time); + + if (retval) + return retval; + + /* wrap that up in a nice GSS-API wrapping */ + 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); + + data_blob_free(&tkt_wrapped); + data_blob_free(&tkt); + + return retval; +} + + +/* + parse a spnego NTLMSSP challenge packet giving two security blobs +*/ +bool spnego_parse_challenge(const DATA_BLOB blob, + DATA_BLOB *chal1, DATA_BLOB *chal2) +{ + bool ret; + ASN1_DATA data; + + ZERO_STRUCTP(chal1); + ZERO_STRUCTP(chal2); + + asn1_load(&data, blob); + asn1_start_tag(&data,ASN1_CONTEXT(1)); + asn1_start_tag(&data,ASN1_SEQUENCE(0)); + + asn1_start_tag(&data,ASN1_CONTEXT(0)); + asn1_check_enumerated(&data,1); + asn1_end_tag(&data); + + asn1_start_tag(&data,ASN1_CONTEXT(1)); + asn1_check_OID(&data, OID_NTLMSSP); + asn1_end_tag(&data); + + asn1_start_tag(&data,ASN1_CONTEXT(2)); + asn1_read_OctetString(&data, chal1); + asn1_end_tag(&data); + + /* the second challenge is optional (XP doesn't send it) */ + if (asn1_tag_remaining(&data)) { + asn1_start_tag(&data,ASN1_CONTEXT(3)); + asn1_read_OctetString(&data, chal2); + asn1_end_tag(&data); + } + + asn1_end_tag(&data); + asn1_end_tag(&data); + + ret = !data.has_error; + + if (data.has_error) { + data_blob_free(chal1); + data_blob_free(chal2); + } + + asn1_free(&data); + return ret; +} + + +/* + generate a SPNEGO auth packet. This will contain the encrypted passwords +*/ +DATA_BLOB spnego_gen_auth(DATA_BLOB blob) +{ + ASN1_DATA data; + DATA_BLOB ret; + + memset(&data, 0, sizeof(data)); + + asn1_push_tag(&data, ASN1_CONTEXT(1)); + asn1_push_tag(&data, ASN1_SEQUENCE(0)); + asn1_push_tag(&data, ASN1_CONTEXT(2)); + asn1_write_OctetString(&data,blob.data,blob.length); + asn1_pop_tag(&data); + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + ret = data_blob(data.data, data.length); + + asn1_free(&data); + + return ret; +} + +/* + parse a SPNEGO auth packet. This contains the encrypted passwords +*/ +bool spnego_parse_auth(DATA_BLOB blob, DATA_BLOB *auth) +{ + ASN1_DATA data; + + asn1_load(&data, blob); + asn1_start_tag(&data, ASN1_CONTEXT(1)); + asn1_start_tag(&data, ASN1_SEQUENCE(0)); + asn1_start_tag(&data, ASN1_CONTEXT(2)); + asn1_read_OctetString(&data,auth); + asn1_end_tag(&data); + asn1_end_tag(&data); + asn1_end_tag(&data); + + if (data.has_error) { + DEBUG(3,("spnego_parse_auth failed at %d\n", (int)data.ofs)); + data_blob_free(auth); + asn1_free(&data); + return False; + } + + asn1_free(&data); + return True; +} + +/* + generate a minimal SPNEGO response packet. Doesn't contain much. +*/ +DATA_BLOB spnego_gen_auth_response(DATA_BLOB *reply, NTSTATUS nt_status, + const char *mechOID) +{ + ASN1_DATA data; + DATA_BLOB ret; + uint8 negResult; + + if (NT_STATUS_IS_OK(nt_status)) { + negResult = SPNEGO_NEG_RESULT_ACCEPT; + } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) { + negResult = SPNEGO_NEG_RESULT_INCOMPLETE; + } else { + negResult = SPNEGO_NEG_RESULT_REJECT; + } + + ZERO_STRUCT(data); + + asn1_push_tag(&data, ASN1_CONTEXT(1)); + asn1_push_tag(&data, ASN1_SEQUENCE(0)); + asn1_push_tag(&data, ASN1_CONTEXT(0)); + asn1_write_enumerated(&data, negResult); + asn1_pop_tag(&data); + + if (mechOID) { + asn1_push_tag(&data,ASN1_CONTEXT(1)); + asn1_write_OID(&data, mechOID); + asn1_pop_tag(&data); + } + + if (reply && reply->data != NULL) { + asn1_push_tag(&data,ASN1_CONTEXT(2)); + asn1_write_OctetString(&data, reply->data, reply->length); + asn1_pop_tag(&data); + } + + asn1_pop_tag(&data); + asn1_pop_tag(&data); + + ret = data_blob(data.data, data.length); + asn1_free(&data); + return ret; +} + +/* + parse a SPNEGO auth packet. This contains the encrypted passwords +*/ +bool spnego_parse_auth_response(DATA_BLOB blob, NTSTATUS nt_status, + const char *mechOID, + DATA_BLOB *auth) +{ + ASN1_DATA data; + uint8 negResult; + + if (NT_STATUS_IS_OK(nt_status)) { + negResult = SPNEGO_NEG_RESULT_ACCEPT; + } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) { + negResult = SPNEGO_NEG_RESULT_INCOMPLETE; + } else { + negResult = SPNEGO_NEG_RESULT_REJECT; + } + + asn1_load(&data, blob); + asn1_start_tag(&data, ASN1_CONTEXT(1)); + asn1_start_tag(&data, ASN1_SEQUENCE(0)); + asn1_start_tag(&data, ASN1_CONTEXT(0)); + asn1_check_enumerated(&data, negResult); + asn1_end_tag(&data); + + *auth = data_blob_null; + + if (asn1_tag_remaining(&data)) { + asn1_start_tag(&data,ASN1_CONTEXT(1)); + asn1_check_OID(&data, mechOID); + asn1_end_tag(&data); + + if (asn1_tag_remaining(&data)) { + asn1_start_tag(&data,ASN1_CONTEXT(2)); + asn1_read_OctetString(&data, auth); + asn1_end_tag(&data); + } + } else if (negResult == SPNEGO_NEG_RESULT_INCOMPLETE) { + data.has_error = 1; + } + + /* Binding against Win2K DC returns a duplicate of the responseToken in + * the optional mechListMIC field. This is a bug in Win2K. We ignore + * this field if it exists. Win2K8 may return a proper mechListMIC at + * which point we need to implement the integrity checking. */ + if (asn1_tag_remaining(&data)) { + DATA_BLOB mechList = data_blob_null; + asn1_start_tag(&data, ASN1_CONTEXT(3)); + asn1_read_OctetString(&data, &mechList); + asn1_end_tag(&data); + data_blob_free(&mechList); + DEBUG(5,("spnego_parse_auth_response received mechListMIC, " + "ignoring.\n")); + } + + asn1_end_tag(&data); + asn1_end_tag(&data); + + if (data.has_error) { + DEBUG(3,("spnego_parse_auth_response failed at %d\n", (int)data.ofs)); + asn1_free(&data); + data_blob_free(auth); + return False; + } + + asn1_free(&data); + return True; +} |