/* * Copyright (c) 1997 - 2002 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_in_tkt.c,v 1.107.2.1 2003/09/18 21:00:09 lha Exp $"); krb5_error_code krb5_init_etype (krb5_context context, unsigned *len, krb5_enctype **val, const krb5_enctype *etypes) { int i; krb5_error_code ret; krb5_enctype *tmp = NULL; ret = 0; if (etypes == NULL) { ret = krb5_get_default_in_tkt_etypes(context, &tmp); if (ret) return ret; etypes = tmp; } for (i = 0; etypes[i]; ++i) ; *len = i; *val = malloc(i * sizeof(**val)); if (i != 0 && *val == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto cleanup; } memmove (*val, etypes, i * sizeof(*tmp)); cleanup: if (tmp != NULL) free (tmp); return ret; } static krb5_error_code decrypt_tkt (krb5_context context, krb5_keyblock *key, krb5_key_usage usage, krb5_const_pointer decrypt_arg, krb5_kdc_rep *dec_rep) { krb5_error_code ret; krb5_data data; size_t size; krb5_crypto crypto; ret = krb5_crypto_init(context, key, 0, &crypto); if (ret) return ret; ret = krb5_decrypt_EncryptedData (context, crypto, usage, &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); if (ret) return ret; return 0; } int _krb5_extract_ticket(krb5_context context, krb5_kdc_rep *rep, krb5_creds *creds, krb5_keyblock *key, krb5_const_pointer keyseed, krb5_key_usage key_usage, krb5_addresses *addrs, unsigned nonce, krb5_boolean allow_server_mismatch, krb5_boolean ignore_cname, krb5_decrypt_proc decrypt_proc, krb5_const_pointer decryptarg) { krb5_error_code ret; krb5_principal tmp_principal; int tmp; time_t tmp_time; krb5_timestamp sec_now; ret = principalname2krb5_principal (&tmp_principal, rep->kdc_rep.cname, rep->kdc_rep.crealm); if (ret) goto out; /* compare client */ if (!ignore_cname) { tmp = krb5_principal_compare (context, tmp_principal, creds->client); if (!tmp) { krb5_free_principal (context, tmp_principal); krb5_clear_error_string (context); ret = KRB5KRB_AP_ERR_MODIFIED; goto out; } } krb5_free_principal (context, creds->client); creds->client = tmp_principal; /* extract ticket */ ASN1_MALLOC_ENCODE(Ticket, creds->ticket.data, creds->ticket.length, &rep->kdc_rep.ticket, &creds->ticket.length, ret); if(ret) goto out; creds->second_ticket.length = 0; creds->second_ticket.data = NULL; /* compare server */ ret = principalname2krb5_principal (&tmp_principal, rep->kdc_rep.ticket.sname, rep->kdc_rep.ticket.realm); if (ret) goto out; if(allow_server_mismatch){ krb5_free_principal(context, creds->server); creds->server = tmp_principal; tmp_principal = NULL; }else{ tmp = krb5_principal_compare (context, tmp_principal, creds->server); krb5_free_principal (context, tmp_principal); if (!tmp) { ret = KRB5KRB_AP_ERR_MODIFIED; krb5_clear_error_string (context); goto out; } } /* decrypt */ if (decrypt_proc == NULL) decrypt_proc = decrypt_tkt; ret = (*decrypt_proc)(context, key, key_usage, decryptarg, rep); if (ret) goto out; #if 0 /* XXX should this decode be here, or in the decrypt_proc? */ ret = krb5_decode_keyblock(context, &rep->enc_part.key, 1); if(ret) goto out; #endif /* compare nonces */ if (nonce != rep->enc_part.nonce) { ret = KRB5KRB_AP_ERR_MODIFIED; krb5_set_error_string(context, "malloc: out of memory"); goto out; } /* set kdc-offset */ krb5_timeofday (context, &sec_now); if (rep->enc_part.flags.initial && context->kdc_sec_offset == 0 && krb5_config_get_bool (context, NULL, "libdefaults", "kdc_timesync", NULL)) { context->kdc_sec_offset = rep->enc_part.authtime - sec_now; krb5_timeofday (context, &sec_now); } /* check all times */ if (rep->enc_part.starttime) { tmp_time = *rep->enc_part.starttime; } else tmp_time = rep->enc_part.authtime; if (creds->times.starttime == 0 && abs(tmp_time - sec_now) > context->max_skew) { ret = KRB5KRB_AP_ERR_SKEW; krb5_set_error_string (context, "time skew (%d) larger than max (%d)", abs(tmp_time - sec_now), (int)context->max_skew); goto out; } if (creds->times.starttime != 0 && tmp_time != creds->times.starttime) { krb5_clear_error_string (context); ret = KRB5KRB_AP_ERR_MODIFIED; goto out; } creds->times.starttime = tmp_time; if (rep->enc_part.renew_till) { tmp_time = *rep->enc_part.renew_till; } else tmp_time = 0; if (creds->times.renew_till != 0 && tmp_time > creds->times.renew_till) { krb5_clear_error_string (context); ret = KRB5KRB_AP_ERR_MODIFIED; goto out; } creds->times.renew_till = tmp_time; creds->times.authtime = rep->enc_part.authtime; if (creds->times.endtime != 0 && rep->enc_part.endtime > creds->times.endtime) { krb5_clear_error_string (context); ret = KRB5KRB_AP_ERR_MODIFIED; goto out; } creds->times.endtime = rep->enc_part.endtime; if(rep->enc_part.caddr) krb5_copy_addresses (context, rep->enc_part.caddr, &creds->addresses); else if(addrs) krb5_copy_addresses (context, addrs, &creds->addresses); else { creds->addresses.len = 0; creds->addresses.val = NULL; } creds->flags.b = rep->enc_part.flags; creds->authdata.len = 0; creds->authdata.val = NULL; creds->session.keyvalue.length = 0; creds->session.keyvalue.data = NULL; creds->session.keytype = rep->enc_part.key.keytype; ret = krb5_data_copy (&creds->session.keyvalue, rep->enc_part.key.keyvalue.data, rep->enc_part.key.keyvalue.length); out: memset (rep->enc_part.key.keyvalue.data, 0, rep->enc_part.key.keyvalue.length); return ret; } static krb5_error_code make_pa_enc_timestamp(krb5_context context, PA_DATA *pa, krb5_enctype etype, krb5_keyblock *key) { PA_ENC_TS_ENC p; unsigned char *buf; size_t buf_size; size_t len; EncryptedData encdata; krb5_error_code ret; int32_t sec, usec; int usec2; krb5_crypto crypto; krb5_us_timeofday (context, &sec, &usec); p.patimestamp = sec; usec2 = usec; p.pausec = &usec2; ASN1_MALLOC_ENCODE(PA_ENC_TS_ENC, buf, buf_size, &p, &len, ret); if (ret) return ret; if(buf_size != len) krb5_abortx(context, "internal error in ASN.1 encoder"); ret = krb5_crypto_init(context, key, 0, &crypto); if (ret) { free(buf); return ret; } ret = krb5_encrypt_EncryptedData(context, crypto, KRB5_KU_PA_ENC_TIMESTAMP, buf, len, 0, &encdata); free(buf); krb5_crypto_destroy(context, crypto); if (ret) return ret; ASN1_MALLOC_ENCODE(EncryptedData, buf, buf_size, &encdata, &len, ret); free_EncryptedData(&encdata); if (ret) return ret; if(buf_size != len) krb5_abortx(context, "internal error in ASN.1 encoder"); pa->padata_type = KRB5_PADATA_ENC_TIMESTAMP; pa->padata_value.length = len; pa->padata_value.data = buf; return 0; } static krb5_error_code add_padata(krb5_context context, METHOD_DATA *md, krb5_principal client, krb5_key_proc key_proc, krb5_const_pointer keyseed, krb5_enctype *enctypes, unsigned netypes, krb5_salt *salt) { krb5_error_code ret; PA_DATA *pa2; krb5_salt salt2; krb5_enctype *ep; int i; if(salt == NULL) { /* default to standard salt */ ret = krb5_get_pw_salt (context, client, &salt2); salt = &salt2; } if (!enctypes) { enctypes = context->etypes; netypes = 0; for (ep = enctypes; *ep != ETYPE_NULL; ep++) netypes++; } pa2 = realloc (md->val, (md->len + netypes) * sizeof(*md->val)); if (pa2 == NULL) { krb5_set_error_string(context, "malloc: out of memory"); return ENOMEM; } md->val = pa2; for (i = 0; i < netypes; ++i) { krb5_keyblock *key; ret = (*key_proc)(context, enctypes[i], *salt, keyseed, &key); if (ret) continue; ret = make_pa_enc_timestamp (context, &md->val[md->len], enctypes[i], key); krb5_free_keyblock (context, key); if (ret) return ret; ++md->len; } if(salt == &salt2) krb5_free_salt(context, salt2); return 0; } static krb5_error_code init_as_req (krb5_context context, krb5_kdc_flags opts, krb5_creds *creds, const krb5_addresses *addrs, const krb5_enctype *etypes, const krb5_preauthtype *ptypes, const krb5_preauthdata *preauth, krb5_key_proc key_proc, krb5_const_pointer keyseed, unsigned nonce, AS_REQ *a) { krb5_error_code ret; krb5_salt salt; memset(a, 0, sizeof(*a)); a->pvno = 5; a->msg_type = krb_as_req; a->req_body.kdc_options = opts.b; a->req_body.cname = malloc(sizeof(*a->req_body.cname)); if (a->req_body.cname == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto fail; } a->req_body.sname = malloc(sizeof(*a->req_body.sname)); if (a->req_body.sname == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto fail; } ret = krb5_principal2principalname (a->req_body.cname, creds->client); if (ret) goto fail; ret = krb5_principal2principalname (a->req_body.sname, creds->server); if (ret) goto fail; ret = copy_Realm(&creds->client->realm, &a->req_body.realm); if (ret) goto fail; if(creds->times.starttime) { a->req_body.from = malloc(sizeof(*a->req_body.from)); if (a->req_body.from == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto fail; } *a->req_body.from = creds->times.starttime; } if(creds->times.endtime){ ALLOC(a->req_body.till, 1); *a->req_body.till = creds->times.endtime; } if(creds->times.renew_till){ a->req_body.rtime = malloc(sizeof(*a->req_body.rtime)); if (a->req_body.rtime == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto fail; } *a->req_body.rtime = creds->times.renew_till; } a->req_body.nonce = nonce; ret = krb5_init_etype (context, &a->req_body.etype.len, &a->req_body.etype.val, etypes); if (ret) goto fail; /* * This means no addresses */ if (addrs && addrs->len == 0) { a->req_body.addresses = NULL; } else { a->req_body.addresses = malloc(sizeof(*a->req_body.addresses)); if (a->req_body.addresses == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto fail; } if (addrs) ret = krb5_copy_addresses(context, addrs, a->req_body.addresses); else { ret = krb5_get_all_client_addrs (context, a->req_body.addresses); if(ret == 0 && a->req_body.addresses->len == 0) { free(a->req_body.addresses); a->req_body.addresses = NULL; } } if (ret) return ret; } a->req_body.enc_authorization_data = NULL; a->req_body.additional_tickets = NULL; if(preauth != NULL) { int i; ALLOC(a->padata, 1); if(a->padata == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto fail; } for(i = 0; i < preauth->len; i++) { if(preauth->val[i].type == KRB5_PADATA_ENC_TIMESTAMP){ int j; PA_DATA *tmp = realloc(a->padata->val, (a->padata->len + preauth->val[i].info.len) * sizeof(*a->padata->val)); if(tmp == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto fail; } a->padata->val = tmp; for(j = 0; j < preauth->val[i].info.len; j++) { krb5_salt *sp = &salt; if(preauth->val[i].info.val[j].salttype) salt.salttype = *preauth->val[i].info.val[j].salttype; else salt.salttype = KRB5_PW_SALT; if(preauth->val[i].info.val[j].salt) salt.saltvalue = *preauth->val[i].info.val[j].salt; else if(salt.salttype == KRB5_PW_SALT) sp = NULL; else krb5_data_zero(&salt.saltvalue); ret = add_padata(context, a->padata, creds->client, key_proc, keyseed, &preauth->val[i].info.val[j].etype, 1, sp); if (ret == 0) break; } } } } else /* not sure this is the way to use `ptypes' */ if (ptypes == NULL || *ptypes == KRB5_PADATA_NONE) a->padata = NULL; else if (*ptypes == KRB5_PADATA_ENC_TIMESTAMP) { ALLOC(a->padata, 1); if (a->padata == NULL) { ret = ENOMEM; krb5_set_error_string(context, "malloc: out of memory"); goto fail; } a->padata->len = 0; a->padata->val = NULL; /* make a v5 salted pa-data */ add_padata(context, a->padata, creds->client, key_proc, keyseed, a->req_body.etype.val, a->req_body.etype.len, NULL); /* make a v4 salted pa-data */ salt.salttype = KRB5_PW_SALT; krb5_data_zero(&salt.saltvalue); add_padata(context, a->padata, creds->client, key_proc, keyseed, a->req_body.etype.val, a->req_body.etype.len, &salt); } else { krb5_set_error_string (context, "pre-auth type %d not supported", *ptypes); ret = KRB5_PREAUTH_BAD_TYPE; goto fail; } return 0; fail: free_AS_REQ(a); return ret; } static int set_ptypes(krb5_context context, KRB_ERROR *error, krb5_preauthtype **ptypes, krb5_preauthdata **preauth) { static krb5_preauthdata preauth2; static krb5_preauthtype ptypes2[] = { KRB5_PADATA_ENC_TIMESTAMP, KRB5_PADATA_NONE }; if(error->e_data) { METHOD_DATA md; int i; decode_METHOD_DATA(error->e_data->data, error->e_data->length, &md, NULL); for(i = 0; i < md.len; i++){ switch(md.val[i].padata_type){ case KRB5_PADATA_ENC_TIMESTAMP: *ptypes = ptypes2; break; case KRB5_PADATA_ETYPE_INFO: *preauth = &preauth2; ALLOC_SEQ(*preauth, 1); (*preauth)->val[0].type = KRB5_PADATA_ENC_TIMESTAMP; krb5_decode_ETYPE_INFO(context, md.val[i].padata_value.data, md.val[i].padata_value.length, &(*preauth)->val[0].info, NULL); break; default: break; } } free_METHOD_DATA(&md); } else { *ptypes = ptypes2; } return(1); } krb5_error_code krb5_get_in_cred(krb5_context context, krb5_flags options, const krb5_addresses *addrs, const krb5_enctype *etypes, const krb5_preauthtype *ptypes, const krb5_preauthdata *preauth, krb5_key_proc key_proc, krb5_const_pointer keyseed, krb5_decrypt_proc decrypt_proc, krb5_const_pointer decryptarg, krb5_creds *creds, krb5_kdc_rep *ret_as_reply) { krb5_error_code ret; AS_REQ a; krb5_kdc_rep rep; krb5_data req, resp; size_t len; krb5_salt salt; krb5_keyblock *key; size_t size; krb5_kdc_flags opts; PA_DATA *pa; krb5_enctype etype; krb5_preauthdata *my_preauth = NULL; unsigned nonce; int done; opts.i = options; krb5_generate_random_block (&nonce, sizeof(nonce)); nonce &= 0xffffffff; do { done = 1; ret = init_as_req (context, opts, creds, addrs, etypes, ptypes, preauth, key_proc, keyseed, nonce, &a); if (my_preauth) { free_ETYPE_INFO(&my_preauth->val[0].info); free (my_preauth->val); } if (ret) return ret; ASN1_MALLOC_ENCODE(AS_REQ, req.data, req.length, &a, &len, ret); free_AS_REQ(&a); if (ret) return ret; if(len != req.length) krb5_abortx(context, "internal error in ASN.1 encoder"); ret = krb5_sendto_kdc (context, &req, &creds->client->realm, &resp); krb5_data_free(&req); if (ret) return ret; memset (&rep, 0, sizeof(rep)); ret = decode_AS_REP(resp.data, resp.length, &rep.kdc_rep, &size); if(ret) { /* let's try to parse it as a KRB-ERROR */ KRB_ERROR error; int ret2; ret2 = krb5_rd_error(context, &resp, &error); if(ret2 && resp.data && ((char*)resp.data)[0] == 4) ret = KRB5KRB_AP_ERR_V4_REPLY; krb5_data_free(&resp); if (ret2 == 0) { ret = krb5_error_from_rd_error(context, &error, creds); /* if no preauth was set and KDC requires it, give it one more try */ if (!ptypes && !preauth && ret == KRB5KDC_ERR_PREAUTH_REQUIRED #if 0 || ret == KRB5KDC_ERR_BADOPTION #endif && set_ptypes(context, &error, &ptypes, &my_preauth)) { done = 0; preauth = my_preauth; krb5_free_error_contents(context, &error); krb5_clear_error_string(context); continue; } if(ret_as_reply) ret_as_reply->error = error; else free_KRB_ERROR (&error); return ret; } return ret; } krb5_data_free(&resp); } while(!done); pa = NULL; etype = rep.kdc_rep.enc_part.etype; if(rep.kdc_rep.padata){ int index = 0; pa = krb5_find_padata(rep.kdc_rep.padata->val, rep.kdc_rep.padata->len, KRB5_PADATA_PW_SALT, &index); if(pa == NULL) { index = 0; pa = krb5_find_padata(rep.kdc_rep.padata->val, rep.kdc_rep.padata->len, KRB5_PADATA_AFS3_SALT, &index); } } if(pa) { salt.salttype = pa->padata_type; salt.saltvalue = pa->padata_value; ret = (*key_proc)(context, etype, salt, keyseed, &key); } else { /* make a v5 salted pa-data */ ret = krb5_get_pw_salt (context, creds->client, &salt); if (ret) goto out; ret = (*key_proc)(context, etype, salt, keyseed, &key); krb5_free_salt(context, salt); } if (ret) goto out; ret = _krb5_extract_ticket(context, &rep, creds, key, keyseed, KRB5_KU_AS_REP_ENC_PART, NULL, nonce, FALSE, opts.b.request_anonymous, decrypt_proc, decryptarg); memset (key->keyvalue.data, 0, key->keyvalue.length); krb5_free_keyblock_contents (context, key); free (key); out: if (ret == 0 && ret_as_reply) *ret_as_reply = rep; else krb5_free_kdc_rep (context, &rep); return ret; } krb5_error_code krb5_get_in_tkt(krb5_context context, krb5_flags options, const krb5_addresses *addrs, const krb5_enctype *etypes, const krb5_preauthtype *ptypes, krb5_key_proc key_proc, krb5_const_pointer keyseed, krb5_decrypt_proc decrypt_proc, krb5_const_pointer decryptarg, krb5_creds *creds, krb5_ccache ccache, krb5_kdc_rep *ret_as_reply) { krb5_error_code ret; krb5_kdc_flags opts; opts.i = 0; opts.b = int2KDCOptions(options); ret = krb5_get_in_cred (context, opts.i, addrs, etypes, ptypes, NULL, key_proc, keyseed, decrypt_proc, decryptarg, creds, ret_as_reply); if(ret) return ret; if (ccache) ret = krb5_cc_store_cred (context, ccache, creds); return ret; }