diff options
Diffstat (limited to 'crypto/heimdal/lib/krb5/get_cred.c')
-rw-r--r-- | crypto/heimdal/lib/krb5/get_cred.c | 776 |
1 files changed, 776 insertions, 0 deletions
diff --git a/crypto/heimdal/lib/krb5/get_cred.c b/crypto/heimdal/lib/krb5/get_cred.c new file mode 100644 index 0000000..61951c1 --- /dev/null +++ b/crypto/heimdal/lib/krb5/get_cred.c @@ -0,0 +1,776 @@ +/* + * Copyright (c) 1997, 1998, 1999 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <krb5_locl.h> + +RCSID("$Id: get_cred.c,v 1.75 1999/12/02 17:05:09 joda Exp $"); + +/* + * Take the `body' and encode it into `padata' using the credentials + * in `creds'. + */ + +static krb5_error_code +make_pa_tgs_req(krb5_context context, + krb5_auth_context ac, + KDC_REQ_BODY *body, + PA_DATA *padata, + krb5_creds *creds) +{ + u_char *buf; + size_t buf_size; + size_t len; + krb5_data in_data; + krb5_error_code ret; + + buf_size = 1024; + buf = malloc (buf_size); + if (buf == NULL) + return ENOMEM; + + do { + ret = encode_KDC_REQ_BODY(buf + buf_size - 1, buf_size, + body, &len); + if (ret){ + if (ret == ASN1_OVERFLOW) { + u_char *tmp; + + buf_size *= 2; + tmp = realloc (buf, buf_size); + if (tmp == NULL) { + ret = ENOMEM; + goto out; + } + buf = tmp; + } else { + goto out; + } + } + } while (ret == ASN1_OVERFLOW); + + in_data.length = len; + in_data.data = buf + buf_size - len; + ret = krb5_mk_req_internal(context, &ac, 0, &in_data, creds, + &padata->padata_value, + KRB5_KU_TGS_REQ_AUTH_CKSUM); +out: + free (buf); + if(ret) + return ret; + padata->padata_type = pa_tgs_req; + return 0; +} + +/* + * Set the `enc-authorization-data' in `req_body' based on `authdata' + */ + +static krb5_error_code +set_auth_data (krb5_context context, + KDC_REQ_BODY *req_body, + krb5_authdata *authdata, + krb5_keyblock *key) +{ + if(authdata->len) { + size_t len; + unsigned char *buf; + krb5_crypto crypto; + krb5_error_code ret; + + len = length_AuthorizationData(authdata); + buf = malloc(len); + if (buf == NULL) + return ENOMEM; + ret = encode_AuthorizationData(buf + len - 1, + len, authdata, &len); + if (ret) { + free (buf); + return ret; + } + + ALLOC(req_body->enc_authorization_data, 1); + if (req_body->enc_authorization_data == NULL) { + free (buf); + return ret; + } + ret = krb5_crypto_init(context, key, 0, &crypto); + if (ret) { + free (buf); + free (req_body->enc_authorization_data); + return ret; + } + krb5_encrypt_EncryptedData(context, + crypto, + KRB5_KU_TGS_REQ_AUTH_DAT_SUBKEY, + /* KRB5_KU_TGS_REQ_AUTH_DAT_SESSION? */ + buf, + len, + 0, + req_body->enc_authorization_data); + free (buf); + krb5_crypto_destroy(context, crypto); + } else { + req_body->enc_authorization_data = NULL; + } + return 0; +} + +/* + * Create a tgs-req in `t' with `addresses', `flags', `second_ticket' + * (if not-NULL), `in_creds', `krbtgt', and returning the generated + * subkey in `subkey'. + */ + +static krb5_error_code +init_tgs_req (krb5_context context, + krb5_ccache ccache, + krb5_addresses *addresses, + krb5_kdc_flags flags, + Ticket *second_ticket, + krb5_creds *in_creds, + krb5_creds *krbtgt, + unsigned nonce, + krb5_keyblock **subkey, + TGS_REQ *t) +{ + krb5_error_code ret; + + memset(t, 0, sizeof(*t)); + t->pvno = 5; + t->msg_type = krb_tgs_req; + if (in_creds->session.keytype) { + ret = krb5_keytype_to_enctypes_default (context, + in_creds->session.keytype, + &t->req_body.etype.len, + &t->req_body.etype.val); + } else { + ret = krb5_init_etype(context, + &t->req_body.etype.len, + &t->req_body.etype.val, + NULL); + } + if (ret) + goto fail; + t->req_body.addresses = addresses; + t->req_body.kdc_options = flags.b; + ret = copy_Realm(&in_creds->server->realm, &t->req_body.realm); + if (ret) + goto fail; + ALLOC(t->req_body.sname, 1); + if (t->req_body.sname == NULL) { + ret = ENOMEM; + goto fail; + } + ret = copy_PrincipalName(&in_creds->server->name, t->req_body.sname); + if (ret) + goto fail; + + /* req_body.till should be NULL if there is no endtime specified, + but old MIT code (like DCE secd) doesn't like that */ + ALLOC(t->req_body.till, 1); + if(t->req_body.till == NULL){ + ret = ENOMEM; + goto fail; + } + *t->req_body.till = in_creds->times.endtime; + + t->req_body.nonce = nonce; + if(second_ticket){ + ALLOC(t->req_body.additional_tickets, 1); + if (t->req_body.additional_tickets == NULL) { + ret = ENOMEM; + goto fail; + } + ALLOC_SEQ(t->req_body.additional_tickets, 1); + if (t->req_body.additional_tickets->val == NULL) { + ret = ENOMEM; + goto fail; + } + ret = copy_Ticket(second_ticket, t->req_body.additional_tickets->val); + if (ret) + goto fail; + } + ALLOC(t->padata, 1); + if (t->padata == NULL) { + ret = ENOMEM; + goto fail; + } + ALLOC_SEQ(t->padata, 1); + if (t->padata->val == NULL) { + ret = ENOMEM; + goto fail; + } + + { + krb5_auth_context ac; + krb5_keyblock *key; + + ret = krb5_auth_con_init(context, &ac); + if(ret) + goto fail; + ret = krb5_generate_subkey (context, &krbtgt->session, &key); + if (ret) { + krb5_auth_con_free (context, ac); + goto fail; + } + ret = krb5_auth_con_setlocalsubkey(context, ac, key); + if (ret) { + krb5_free_keyblock (context, key); + krb5_auth_con_free (context, ac); + goto fail; + } + + ret = set_auth_data (context, &t->req_body, &in_creds->authdata, key); + if (ret) { + krb5_free_keyblock (context, key); + krb5_auth_con_free (context, ac); + goto fail; + } + + ret = make_pa_tgs_req(context, + ac, + &t->req_body, + t->padata->val, + krbtgt); + if(ret) { + krb5_free_keyblock (context, key); + krb5_auth_con_free(context, ac); + goto fail; + } + *subkey = key; + + krb5_auth_con_free(context, ac); + } +fail: + if (ret) + free_TGS_REQ (t); + return ret; +} + +static krb5_error_code +get_krbtgt(krb5_context context, + krb5_ccache id, + krb5_realm realm, + krb5_creds **cred) +{ + krb5_error_code ret; + krb5_creds tmp_cred; + + memset(&tmp_cred, 0, sizeof(tmp_cred)); + + ret = krb5_make_principal(context, + &tmp_cred.server, + realm, + KRB5_TGS_NAME, + realm, + NULL); + if(ret) + return ret; + ret = krb5_get_credentials(context, + KRB5_GC_CACHED, + id, + &tmp_cred, + cred); + krb5_free_principal(context, tmp_cred.server); + if(ret) + return ret; + return 0; +} + +/* DCE compatible decrypt proc */ +static krb5_error_code +decrypt_tkt_with_subkey (krb5_context context, + krb5_keyblock *key, + krb5_key_usage usage, + krb5_const_pointer subkey, + krb5_kdc_rep *dec_rep) +{ + krb5_error_code ret; + krb5_data data; + size_t size; + krb5_crypto crypto; + + krb5_crypto_init(context, key, 0, &crypto); + ret = krb5_decrypt_EncryptedData (context, + crypto, + usage, + &dec_rep->kdc_rep.enc_part, + &data); + krb5_crypto_destroy(context, crypto); + if(ret && subkey){ + /* DCE compat -- try to decrypt with subkey */ + krb5_crypto_init(context, (krb5_keyblock*)subkey, 0, &crypto); + ret = krb5_decrypt_EncryptedData (context, + crypto, + KRB5_KU_TGS_REP_ENC_PART_SUB_KEY, + &dec_rep->kdc_rep.enc_part, + &data); + krb5_crypto_destroy(context, crypto); + } + if (ret) + return ret; + + ret = krb5_decode_EncASRepPart(context, + data.data, + data.length, + &dec_rep->enc_part, + &size); + if (ret) + ret = krb5_decode_EncTGSRepPart(context, + data.data, + data.length, + &dec_rep->enc_part, + &size); + krb5_data_free (&data); + return ret; +} + +static krb5_error_code +get_cred_kdc(krb5_context context, + krb5_ccache id, + krb5_kdc_flags flags, + krb5_addresses *addresses, + krb5_creds *in_creds, + krb5_creds *krbtgt, + krb5_creds *out_creds) +{ + TGS_REQ req; + krb5_data enc; + krb5_data resp; + krb5_kdc_rep rep; + KRB_ERROR error; + krb5_error_code ret; + unsigned nonce; + krb5_keyblock *subkey = NULL; + u_char *buf = NULL; + size_t buf_size; + size_t len; + Ticket second_ticket; + + krb5_generate_random_block(&nonce, sizeof(nonce)); + nonce &= 0xffffffff; + + if(flags.b.enc_tkt_in_skey){ + ret = decode_Ticket(in_creds->second_ticket.data, + in_creds->second_ticket.length, + &second_ticket, &len); + if(ret) + return ret; + } + + ret = init_tgs_req (context, + id, + addresses, + flags, + flags.b.enc_tkt_in_skey ? &second_ticket : NULL, + in_creds, + krbtgt, + nonce, + &subkey, + &req); + if(flags.b.enc_tkt_in_skey) + free_Ticket(&second_ticket); + if (ret) + goto out; + + buf_size = 1024; + buf = malloc (buf_size); + if (buf == NULL) { + ret = ENOMEM; + goto out; + } + + do { + ret = encode_TGS_REQ (buf + buf_size - 1, buf_size, + &req, &enc.length); + if (ret) { + if (ret == ASN1_OVERFLOW) { + u_char *tmp; + + buf_size *= 2; + tmp = realloc (buf, buf_size); + if (tmp == NULL) { + ret = ENOMEM; + goto out; + } + buf = tmp; + } else { + goto out; + } + } + } while (ret == ASN1_OVERFLOW); + + /* don't free addresses */ + req.req_body.addresses = NULL; + free_TGS_REQ(&req); + + enc.data = buf + buf_size - enc.length; + if (ret) + goto out; + + /* + * Send and receive + */ + + ret = krb5_sendto_kdc (context, &enc, + &krbtgt->server->name.name_string.val[1], &resp); + if(ret) + goto out; + + memset(&rep, 0, sizeof(rep)); + if(decode_TGS_REP(resp.data, resp.length, &rep.kdc_rep, &len) == 0){ + ret = krb5_copy_principal(context, + in_creds->client, + &out_creds->client); + if(ret) + goto out; + ret = krb5_copy_principal(context, + in_creds->server, + &out_creds->server); + if(ret) + goto out; + /* this should go someplace else */ + out_creds->times.endtime = in_creds->times.endtime; + + ret = _krb5_extract_ticket(context, + &rep, + out_creds, + &krbtgt->session, + NULL, + KRB5_KU_TGS_REP_ENC_PART_SESSION, + &krbtgt->addresses, + nonce, + TRUE, + decrypt_tkt_with_subkey, + subkey); + krb5_free_kdc_rep(context, &rep); + if (ret) + goto out; + }else if(krb5_rd_error(context, &resp, &error) == 0){ + ret = error.error_code; + free_KRB_ERROR(&error); + }else if(resp.data && ((char*)resp.data)[0] == 4) + ret = KRB5KRB_AP_ERR_V4_REPLY; + else + ret = KRB5KRB_AP_ERR_MSG_TYPE; + krb5_data_free(&resp); +out: + if(subkey){ + krb5_free_keyblock_contents(context, subkey); + free(subkey); + } + if (buf) + free (buf); + return ret; + +} + +/* same as above, just get local addresses first */ + +static krb5_error_code +get_cred_kdc_la(krb5_context context, krb5_ccache id, krb5_kdc_flags flags, + krb5_creds *in_creds, krb5_creds *krbtgt, + krb5_creds *out_creds) +{ + krb5_error_code ret; + krb5_addresses addresses; + + krb5_get_all_client_addrs(context, &addresses); + ret = get_cred_kdc(context, id, flags, &addresses, + in_creds, krbtgt, out_creds); + krb5_free_addresses(context, &addresses); + return ret; +} + +krb5_error_code +krb5_get_kdc_cred(krb5_context context, + krb5_ccache id, + krb5_kdc_flags flags, + krb5_addresses *addresses, + Ticket *second_ticket, + krb5_creds *in_creds, + krb5_creds **out_creds + ) +{ + krb5_error_code ret; + krb5_creds *krbtgt; + *out_creds = calloc(1, sizeof(**out_creds)); + if(*out_creds == NULL) + return ENOMEM; + ret = get_krbtgt (context, + id, + in_creds->server->realm, + &krbtgt); + if(ret) { + free(*out_creds); + return ret; + } + ret = get_cred_kdc(context, id, flags, addresses, + in_creds, krbtgt, *out_creds); + krb5_free_creds (context, krbtgt); + if(ret) + free(*out_creds); + return ret; +} + + +static krb5_error_code +find_cred(krb5_context context, + krb5_ccache id, + krb5_principal server, + krb5_creds **tgts, + krb5_creds *out_creds) +{ + krb5_error_code ret; + krb5_creds mcreds; + mcreds.server = server; + ret = krb5_cc_retrieve_cred(context, id, KRB5_TC_DONT_MATCH_REALM, + &mcreds, out_creds); + if(ret == 0) + return 0; + while(tgts && *tgts){ + if(krb5_compare_creds(context, KRB5_TC_DONT_MATCH_REALM, + &mcreds, *tgts)){ + ret = krb5_copy_creds_contents(context, *tgts, out_creds); + return ret; + } + tgts++; + } + return KRB5_CC_NOTFOUND; +} + +static krb5_error_code +add_cred(krb5_context context, krb5_creds ***tgts, krb5_creds *tkt) +{ + int i; + krb5_error_code ret; + krb5_creds **tmp = *tgts; + for(i = 0; tmp && tmp[i]; i++); /* XXX */ + tmp = realloc(tmp, (i+2)*sizeof(*tmp)); + if(tmp == NULL) + return ENOMEM; + *tgts = tmp; + ret = krb5_copy_creds(context, tkt, &tmp[i]); + tmp[i+1] = NULL; + return ret; +} + +/* +get_cred(server) + creds = cc_get_cred(server) + if(creds) return creds + tgt = cc_get_cred(krbtgt/server_realm@any_realm) + if(tgt) + return get_cred_tgt(server, tgt) + if(client_realm == server_realm) + return NULL + tgt = get_cred(krbtgt/server_realm@client_realm) + while(tgt_inst != server_realm) + tgt = get_cred(krbtgt/server_realm@tgt_inst) + return get_cred_tgt(server, tgt) + */ + +static krb5_error_code +get_cred_from_kdc_flags(krb5_context context, + krb5_kdc_flags flags, + krb5_ccache ccache, + krb5_creds *in_creds, + krb5_creds **out_creds, + krb5_creds ***ret_tgts) +{ + krb5_error_code ret; + krb5_creds *tgt, tmp_creds; + krb5_realm client_realm, server_realm; + + *out_creds = NULL; + + client_realm = *krb5_princ_realm(context, in_creds->client); + server_realm = *krb5_princ_realm(context, in_creds->server); + memset(&tmp_creds, 0, sizeof(tmp_creds)); + ret = krb5_copy_principal(context, in_creds->client, &tmp_creds.client); + if(ret) + return ret; + ret = krb5_make_principal(context, + &tmp_creds.server, + client_realm, + KRB5_TGS_NAME, + server_realm, + NULL); + if(ret){ + krb5_free_principal(context, tmp_creds.client); + return ret; + } + { + krb5_creds tgts; + /* XXX try krb5_cc_retrieve_cred first? */ + ret = find_cred(context, ccache, tmp_creds.server, + *ret_tgts, &tgts); + if(ret == 0){ + *out_creds = calloc(1, sizeof(**out_creds)); + if(*out_creds == NULL) + ret = ENOMEM; + else { + ret = get_cred_kdc_la(context, ccache, flags, + in_creds, &tgts, *out_creds); + if (ret) + free (*out_creds); + } + krb5_free_creds_contents(context, &tgts); + krb5_free_principal(context, tmp_creds.server); + krb5_free_principal(context, tmp_creds.client); + return ret; + } + } + if(krb5_realm_compare(context, in_creds->client, in_creds->server)) + return KRB5_CC_NOTFOUND; + /* XXX this can loop forever */ + while(1){ + general_string tgt_inst; + krb5_kdc_flags f; + f.i = 0; + ret = get_cred_from_kdc_flags(context, flags, ccache, &tmp_creds, + &tgt, ret_tgts); + if(ret) { + krb5_free_principal(context, tmp_creds.server); + krb5_free_principal(context, tmp_creds.client); + return ret; + } + ret = add_cred(context, ret_tgts, tgt); + if(ret) { + krb5_free_principal(context, tmp_creds.server); + krb5_free_principal(context, tmp_creds.client); + return ret; + } + tgt_inst = tgt->server->name.name_string.val[1]; + if(strcmp(tgt_inst, server_realm) == 0) + break; + krb5_free_principal(context, tmp_creds.server); + ret = krb5_make_principal(context, &tmp_creds.server, + tgt_inst, KRB5_TGS_NAME, server_realm, NULL); + if(ret) { + krb5_free_principal(context, tmp_creds.server); + krb5_free_principal(context, tmp_creds.client); + return ret; + } + ret = krb5_free_creds(context, tgt); + if(ret) { + krb5_free_principal(context, tmp_creds.server); + krb5_free_principal(context, tmp_creds.client); + return ret; + } + } + + krb5_free_principal(context, tmp_creds.server); + krb5_free_principal(context, tmp_creds.client); + *out_creds = calloc(1, sizeof(**out_creds)); + if(*out_creds == NULL) + ret = ENOMEM; + else { + ret = get_cred_kdc_la(context, ccache, flags, + in_creds, tgt, *out_creds); + if (ret) + free (*out_creds); + } + krb5_free_creds(context, tgt); + return ret; +} + +krb5_error_code +krb5_get_cred_from_kdc(krb5_context context, + krb5_ccache ccache, + krb5_creds *in_creds, + krb5_creds **out_creds, + krb5_creds ***ret_tgts) +{ + krb5_kdc_flags f; + f.i = 0; + return get_cred_from_kdc_flags(context, f, ccache, + in_creds, out_creds, ret_tgts); +} + + +krb5_error_code +krb5_get_credentials_with_flags(krb5_context context, + krb5_flags options, + krb5_kdc_flags flags, + krb5_ccache ccache, + krb5_creds *in_creds, + krb5_creds **out_creds) +{ + krb5_error_code ret; + krb5_creds **tgts; + int i; + + *out_creds = calloc(1, sizeof(**out_creds)); + if (*out_creds == NULL) + return ENOMEM; + + ret = krb5_cc_retrieve_cred(context, + ccache, + in_creds->session.keytype ? + KRB5_TC_MATCH_KEYTYPE : 0, + in_creds, *out_creds); + if(ret == 0) + return 0; + free(*out_creds); + if(ret != KRB5_CC_END) + return ret; + if(options & KRB5_GC_CACHED) + return KRB5_CC_NOTFOUND; + if(options & KRB5_GC_USER_USER) + flags.b.enc_tkt_in_skey = 1; + tgts = NULL; + ret = get_cred_from_kdc_flags(context, flags, ccache, + in_creds, out_creds, &tgts); + for(i = 0; tgts && tgts[i]; i++){ + krb5_cc_store_cred(context, ccache, tgts[i]); + krb5_free_creds(context, tgts[i]); + } + free(tgts); + if(ret == 0 && flags.b.enc_tkt_in_skey == 0) + krb5_cc_store_cred(context, ccache, *out_creds); + return ret; +} + +krb5_error_code +krb5_get_credentials(krb5_context context, + krb5_flags options, + krb5_ccache ccache, + krb5_creds *in_creds, + krb5_creds **out_creds) +{ + krb5_kdc_flags flags; + flags.i = 0; + return krb5_get_credentials_with_flags(context, options, flags, + ccache, in_creds, out_creds); +} |