diff options
Diffstat (limited to '')
| -rw-r--r-- | source4/auth/gensec/gensec_krb5.c | 1133 |
1 files changed, 1133 insertions, 0 deletions
diff --git a/source4/auth/gensec/gensec_krb5.c b/source4/auth/gensec/gensec_krb5.c new file mode 100644 index 0000000..104e463 --- /dev/null +++ b/source4/auth/gensec/gensec_krb5.c @@ -0,0 +1,1133 @@ +/* + Unix SMB/CIFS implementation. + + Kerberos backend for GENSEC + + Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004 + Copyright (C) Andrew Tridgell 2001 + Copyright (C) Luke Howard 2002-2003 + Copyright (C) Stefan Metzmacher 2004-2005 + + 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" +#include <tevent.h> +#include "lib/util/tevent_ntstatus.h" +#include "system/kerberos.h" +#include "auth/kerberos/kerberos.h" +#include "auth/auth.h" +#include "lib/tsocket/tsocket.h" +#include "librpc/gen_ndr/dcerpc.h" +#include "auth/credentials/credentials.h" +#include "auth/credentials/credentials_krb5.h" +#include "auth/kerberos/kerberos_credentials.h" +#include "auth/gensec/gensec.h" +#include "auth/gensec/gensec_internal.h" +#include "auth/gensec/gensec_proto.h" +#include "auth/gensec/gensec_toplevel_proto.h" +#include "param/param.h" +#include "auth/auth_sam_reply.h" +#include "lib/util/util_net.h" +#include "../lib/util/asn1.h" +#include "auth/kerberos/pac_utils.h" +#include "gensec_krb5.h" +#include "gensec_krb5_internal.h" +#include "gensec_krb5_helpers.h" + +_PUBLIC_ NTSTATUS gensec_krb5_init(TALLOC_CTX *); + +static int gensec_krb5_destroy(struct gensec_krb5_state *gensec_krb5_state) +{ + if (!gensec_krb5_state->smb_krb5_context) { + /* We can't clean anything else up unless we started up this far */ + return 0; + } + if (gensec_krb5_state->enc_ticket.length) { + smb_krb5_free_data_contents(gensec_krb5_state->smb_krb5_context->krb5_context, + &gensec_krb5_state->enc_ticket); + } + + if (gensec_krb5_state->ticket) { + krb5_free_ticket(gensec_krb5_state->smb_krb5_context->krb5_context, + gensec_krb5_state->ticket); + } + + /* ccache freed in a child destructor */ + + krb5_free_keyblock(gensec_krb5_state->smb_krb5_context->krb5_context, + gensec_krb5_state->keyblock); + + if (gensec_krb5_state->auth_context) { + krb5_auth_con_free(gensec_krb5_state->smb_krb5_context->krb5_context, + gensec_krb5_state->auth_context); + } + + return 0; +} + +static NTSTATUS gensec_krb5_start(struct gensec_security *gensec_security, bool gssapi) +{ + krb5_error_code ret; + struct gensec_krb5_state *gensec_krb5_state; + struct cli_credentials *creds; + const struct tsocket_address *tlocal_addr, *tremote_addr; + krb5_address my_krb5_addr, peer_krb5_addr; + + creds = gensec_get_credentials(gensec_security); + if (!creds) { + return NT_STATUS_INVALID_PARAMETER; + } + + gensec_krb5_state = talloc_zero(gensec_security, struct gensec_krb5_state); + if (!gensec_krb5_state) { + return NT_STATUS_NO_MEMORY; + } + + gensec_security->private_data = gensec_krb5_state; + gensec_krb5_state->gssapi = gssapi; + + talloc_set_destructor(gensec_krb5_state, gensec_krb5_destroy); + + if (cli_credentials_get_krb5_context(creds, + gensec_security->settings->lp_ctx, &gensec_krb5_state->smb_krb5_context)) { + talloc_free(gensec_krb5_state); + return NT_STATUS_INTERNAL_ERROR; + } + + ret = krb5_auth_con_init(gensec_krb5_state->smb_krb5_context->krb5_context, &gensec_krb5_state->auth_context); + if (ret) { + DEBUG(1,("gensec_krb5_start: krb5_auth_con_init failed (%s)\n", + smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, + ret, gensec_krb5_state))); + talloc_free(gensec_krb5_state); + return NT_STATUS_INTERNAL_ERROR; + } + + ret = krb5_auth_con_setflags(gensec_krb5_state->smb_krb5_context->krb5_context, + gensec_krb5_state->auth_context, + KRB5_AUTH_CONTEXT_DO_SEQUENCE); + if (ret) { + DEBUG(1,("gensec_krb5_start: krb5_auth_con_setflags failed (%s)\n", + smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, + ret, gensec_krb5_state))); + talloc_free(gensec_krb5_state); + return NT_STATUS_INTERNAL_ERROR; + } + + tlocal_addr = gensec_get_local_address(gensec_security); + if (tlocal_addr) { + ssize_t sockaddr_ret; + struct samba_sockaddr addr; + bool ok; + + addr.sa_socklen = sizeof(addr.u); + sockaddr_ret = tsocket_address_bsd_sockaddr( + tlocal_addr, &addr.u.sa, addr.sa_socklen); + if (sockaddr_ret < 0) { + talloc_free(gensec_krb5_state); + return NT_STATUS_INTERNAL_ERROR; + } + addr.sa_socklen = sockaddr_ret; + ok = smb_krb5_sockaddr_to_kaddr(&addr.u.ss, &my_krb5_addr); + if (!ok) { + DBG_WARNING("smb_krb5_sockaddr_to_kaddr (local) failed\n"); + talloc_free(gensec_krb5_state); + return NT_STATUS_INTERNAL_ERROR; + } + } + + tremote_addr = gensec_get_remote_address(gensec_security); + if (tremote_addr) { + ssize_t sockaddr_ret; + struct samba_sockaddr addr; + bool ok; + + addr.sa_socklen = sizeof(addr.u); + sockaddr_ret = tsocket_address_bsd_sockaddr( + tremote_addr, &addr.u.sa, addr.sa_socklen); + if (sockaddr_ret < 0) { + talloc_free(gensec_krb5_state); + return NT_STATUS_INTERNAL_ERROR; + } + addr.sa_socklen = sockaddr_ret; + ok = smb_krb5_sockaddr_to_kaddr(&addr.u.ss, &peer_krb5_addr); + if (!ok) { + DBG_WARNING("smb_krb5_sockaddr_to_kaddr (remote) failed\n"); + talloc_free(gensec_krb5_state); + return NT_STATUS_INTERNAL_ERROR; + } + } + + ret = krb5_auth_con_setaddrs(gensec_krb5_state->smb_krb5_context->krb5_context, + gensec_krb5_state->auth_context, + tlocal_addr ? &my_krb5_addr : NULL, + tremote_addr ? &peer_krb5_addr : NULL); + if (ret) { + DEBUG(1,("gensec_krb5_start: krb5_auth_con_setaddrs failed (%s)\n", + smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, + ret, gensec_krb5_state))); + talloc_free(gensec_krb5_state); + return NT_STATUS_INTERNAL_ERROR; + } + + return NT_STATUS_OK; +} + +static NTSTATUS gensec_krb5_common_server_start(struct gensec_security *gensec_security, bool gssapi) +{ + NTSTATUS nt_status; + struct gensec_krb5_state *gensec_krb5_state; + + nt_status = gensec_krb5_start(gensec_security, gssapi); + if (!NT_STATUS_IS_OK(nt_status)) { + return nt_status; + } + + gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + gensec_krb5_state->state_position = GENSEC_KRB5_SERVER_START; + + return NT_STATUS_OK; +} + +static NTSTATUS gensec_krb5_server_start(struct gensec_security *gensec_security) +{ + return gensec_krb5_common_server_start(gensec_security, false); +} + +static NTSTATUS gensec_fake_gssapi_krb5_server_start(struct gensec_security *gensec_security) +{ + return gensec_krb5_common_server_start(gensec_security, true); +} + +static NTSTATUS gensec_krb5_common_client_start(struct gensec_security *gensec_security, bool gssapi) +{ + const char *hostname; + struct gensec_krb5_state *gensec_krb5_state; + NTSTATUS nt_status; + hostname = gensec_get_target_hostname(gensec_security); + if (!hostname) { + DEBUG(3, ("No hostname for target computer passed in, cannot use kerberos for this connection\n")); + return NT_STATUS_INVALID_PARAMETER; + } + if (is_ipaddress(hostname)) { + DEBUG(2, ("Cannot do krb5 to an IP address")); + return NT_STATUS_INVALID_PARAMETER; + } + if (strcmp(hostname, "localhost") == 0) { + DEBUG(2, ("krb5 to 'localhost' does not make sense")); + return NT_STATUS_INVALID_PARAMETER; + } + + nt_status = gensec_krb5_start(gensec_security, gssapi); + if (!NT_STATUS_IS_OK(nt_status)) { + return nt_status; + } + + gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + gensec_krb5_state->state_position = GENSEC_KRB5_CLIENT_START; + gensec_krb5_state->ap_req_options = AP_OPTS_USE_SUBKEY; + + if (gensec_krb5_state->gssapi) { + /* The Fake GSSAPI model emulates Samba3, which does not do mutual authentication */ + if (gensec_setting_bool(gensec_security->settings, "gensec_fake_gssapi_krb5", "mutual", false)) { + gensec_krb5_state->ap_req_options |= AP_OPTS_MUTUAL_REQUIRED; + } + } else { + /* The wrapping for KPASSWD (a user of the raw KRB5 API) should be mutually authenticated */ + if (gensec_setting_bool(gensec_security->settings, "gensec_krb5", "mutual", true)) { + gensec_krb5_state->ap_req_options |= AP_OPTS_MUTUAL_REQUIRED; + } + } + return NT_STATUS_OK; +} + +static NTSTATUS gensec_krb5_common_client_creds(struct gensec_security *gensec_security, + struct tevent_context *ev) +{ + struct gensec_krb5_state *gensec_krb5_state; + krb5_error_code ret; + struct ccache_container *ccache_container; + const char *error_string; + const char *principal; + const char *hostname; + krb5_data in_data = { .length = 0 }; + krb5_data *in_data_p = NULL; +#ifdef SAMBA4_USES_HEIMDAL + struct tevent_context *previous_ev; +#endif + + if (lpcfg_parm_bool(gensec_security->settings->lp_ctx, + NULL, "gensec_krb5", "send_authenticator_checksum", true)) { + in_data_p = &in_data; + } + + gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + + principal = gensec_get_target_principal(gensec_security); + hostname = gensec_get_target_hostname(gensec_security); + + ret = cli_credentials_get_ccache(gensec_get_credentials(gensec_security), + ev, + gensec_security->settings->lp_ctx, &ccache_container, &error_string); + switch (ret) { + case 0: + break; + case KRB5KDC_ERR_PREAUTH_FAILED: + case KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN: + return NT_STATUS_LOGON_FAILURE; + case KRB5_KDC_UNREACH: + DEBUG(3, ("Cannot reach a KDC we require to contact %s: %s\n", principal, error_string)); + return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */ + case KRB5_CC_NOTFOUND: + case KRB5_CC_END: + DEBUG(3, ("Error preparing credentials we require to contact %s : %s\n", principal, error_string)); + return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */ + default: + DEBUG(1, ("gensec_krb5_start: Aquiring initiator credentials failed: %s\n", error_string)); + return NT_STATUS_UNSUCCESSFUL; + } + +#ifdef SAMBA4_USES_HEIMDAL + /* Do this every time, in case we have weird recursive issues here */ + ret = smb_krb5_context_set_event_ctx(gensec_krb5_state->smb_krb5_context, ev, &previous_ev); + if (ret != 0) { + DEBUG(1, ("gensec_krb5_start: Setting event context failed\n")); + return NT_STATUS_NO_MEMORY; + } +#endif + if (principal) { + krb5_principal target_principal; + ret = krb5_parse_name(gensec_krb5_state->smb_krb5_context->krb5_context, principal, + &target_principal); + if (ret == 0) { + krb5_creds this_cred; + krb5_creds *cred; + + ZERO_STRUCT(this_cred); + ret = krb5_cc_get_principal(gensec_krb5_state->smb_krb5_context->krb5_context, + ccache_container->ccache, + &this_cred.client); + if (ret != 0) { + krb5_free_principal(gensec_krb5_state->smb_krb5_context->krb5_context, + target_principal); + return NT_STATUS_UNSUCCESSFUL; + } + + ret = krb5_copy_principal(gensec_krb5_state->smb_krb5_context->krb5_context, + target_principal, + &this_cred.server); + krb5_free_principal(gensec_krb5_state->smb_krb5_context->krb5_context, + target_principal); + if (ret != 0) { + krb5_free_cred_contents(gensec_krb5_state->smb_krb5_context->krb5_context, + &this_cred); + return NT_STATUS_UNSUCCESSFUL; + } + this_cred.times.endtime = 0; + + ret = krb5_get_credentials(gensec_krb5_state->smb_krb5_context->krb5_context, + 0, + ccache_container->ccache, + &this_cred, + &cred); + krb5_free_cred_contents(gensec_krb5_state->smb_krb5_context->krb5_context, + &this_cred); + if (ret != 0) { + return NT_STATUS_UNSUCCESSFUL; + } + + ret = krb5_mk_req_extended(gensec_krb5_state->smb_krb5_context->krb5_context, + &gensec_krb5_state->auth_context, + gensec_krb5_state->ap_req_options, + in_data_p, + cred, + &gensec_krb5_state->enc_ticket); + } + } else { + ret = krb5_mk_req(gensec_krb5_state->smb_krb5_context->krb5_context, + &gensec_krb5_state->auth_context, + gensec_krb5_state->ap_req_options, + discard_const_p(char, gensec_get_target_service(gensec_security)), + discard_const_p(char, hostname), + in_data_p, ccache_container->ccache, + &gensec_krb5_state->enc_ticket); + } + +#ifdef SAMBA4_USES_HEIMDAL + smb_krb5_context_remove_event_ctx(gensec_krb5_state->smb_krb5_context, previous_ev, ev); +#endif + + switch (ret) { + case 0: + return NT_STATUS_OK; + case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN: + DEBUG(3, ("Server [%s] is not registered with our KDC: %s\n", + hostname, smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state))); + return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */ + case KRB5_KDC_UNREACH: + DEBUG(3, ("Cannot reach a KDC we require to contact host [%s]: %s\n", + hostname, smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state))); + return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */ + case KRB5KDC_ERR_PREAUTH_FAILED: + case KRB5KRB_AP_ERR_TKT_EXPIRED: + case KRB5_CC_END: + /* Too much clock skew - we will need to kinit to re-skew the clock */ + case KRB5KRB_AP_ERR_SKEW: + case KRB5_KDCREP_SKEW: + DEBUG(3, ("kerberos (mk_req) failed: %s\n", + smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state))); + FALL_THROUGH; + /* just don't print a message for these really ordinary messages */ + case KRB5_FCC_NOFILE: + case KRB5_CC_NOTFOUND: + case ENOENT: + + return NT_STATUS_UNSUCCESSFUL; + break; + + default: + DEBUG(0, ("kerberos: %s\n", + smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state))); + return NT_STATUS_UNSUCCESSFUL; + } +} + +static NTSTATUS gensec_krb5_client_start(struct gensec_security *gensec_security) +{ + return gensec_krb5_common_client_start(gensec_security, false); +} + +static NTSTATUS gensec_fake_gssapi_krb5_client_start(struct gensec_security *gensec_security) +{ + return gensec_krb5_common_client_start(gensec_security, true); +} + + +/* + generate a krb5 GSS-API wrapper packet given a ticket +*/ +static DATA_BLOB gensec_gssapi_gen_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *ticket, const uint8_t tok_id[2]) +{ + struct asn1_data *data; + DATA_BLOB ret = data_blob_null; + + data = asn1_init(mem_ctx, ASN1_MAX_TREE_DEPTH); + if (!data || !ticket->data) { + return ret; + } + + if (!asn1_push_tag(data, ASN1_APPLICATION(0))) goto err; + if (!asn1_write_OID(data, GENSEC_OID_KERBEROS5)) goto err; + + if (!asn1_write(data, tok_id, 2)) goto err; + if (!asn1_write(data, ticket->data, ticket->length)) goto err; + if (!asn1_pop_tag(data)) goto err; + + + if (!asn1_extract_blob(data, mem_ctx, &ret)) { + goto err; + } + asn1_free(data); + + return ret; + + err: + + DEBUG(1, ("Failed to build krb5 wrapper at offset %d\n", + (int)asn1_current_ofs(data))); + asn1_free(data); + return ret; +} + +/* + parse a krb5 GSS-API wrapper packet giving a ticket +*/ +static bool gensec_gssapi_parse_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *blob, DATA_BLOB *ticket, uint8_t tok_id[2]) +{ + bool ret = false; + struct asn1_data *data = asn1_init(mem_ctx, ASN1_MAX_TREE_DEPTH); + int data_remaining; + + if (!data) { + return false; + } + + if (!asn1_load(data, *blob)) goto err; + if (!asn1_start_tag(data, ASN1_APPLICATION(0))) goto err; + if (!asn1_check_OID(data, GENSEC_OID_KERBEROS5)) goto err; + + data_remaining = asn1_tag_remaining(data); + + if (data_remaining < 3) { + asn1_set_error(data); + } else { + if (!asn1_read(data, tok_id, 2)) goto err; + data_remaining -= 2; + *ticket = data_blob_talloc(mem_ctx, NULL, data_remaining); + if (!asn1_read(data, ticket->data, ticket->length)) goto err; + } + + if (!asn1_end_tag(data)) goto err; + + ret = !asn1_has_error(data); + + err: + + asn1_free(data); + + return ret; +} + +static NTSTATUS gensec_krb5_update_internal(struct gensec_security *gensec_security, + TALLOC_CTX *out_mem_ctx, + struct tevent_context *ev, + const DATA_BLOB in, DATA_BLOB *out) +{ + struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + krb5_error_code ret = 0; + NTSTATUS nt_status; + + switch (gensec_krb5_state->state_position) { + case GENSEC_KRB5_CLIENT_START: + { + DATA_BLOB unwrapped_out; + + nt_status = gensec_krb5_common_client_creds(gensec_security, ev); + if (!NT_STATUS_IS_OK(nt_status)) { + return nt_status; + } + + if (gensec_krb5_state->gssapi) { + unwrapped_out = data_blob_talloc(out_mem_ctx, gensec_krb5_state->enc_ticket.data, gensec_krb5_state->enc_ticket.length); + + /* wrap that up in a nice GSS-API wrapping */ + *out = gensec_gssapi_gen_krb5_wrap(out_mem_ctx, &unwrapped_out, TOK_ID_KRB_AP_REQ); + } else { + *out = data_blob_talloc(out_mem_ctx, gensec_krb5_state->enc_ticket.data, gensec_krb5_state->enc_ticket.length); + } + if (gensec_krb5_state->ap_req_options & AP_OPTS_MUTUAL_REQUIRED) { + gensec_krb5_state->state_position = GENSEC_KRB5_CLIENT_MUTUAL_AUTH; + nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED; + } else { + gensec_krb5_state->state_position = GENSEC_KRB5_DONE; + nt_status = NT_STATUS_OK; + } + return nt_status; + } + + case GENSEC_KRB5_CLIENT_MUTUAL_AUTH: + { + DATA_BLOB unwrapped_in; + krb5_data inbuf; + krb5_ap_rep_enc_part *repl = NULL; + uint8_t tok_id[2]; + + if (gensec_krb5_state->gssapi) { + if (!gensec_gssapi_parse_krb5_wrap(out_mem_ctx, &in, &unwrapped_in, tok_id)) { + DEBUG(1,("gensec_gssapi_parse_krb5_wrap(mutual authentication) failed to parse\n")); + dump_data_pw("Mutual authentication message:\n", in.data, in.length); + return NT_STATUS_INVALID_PARAMETER; + } + } else { + unwrapped_in = in; + } + /* TODO: check the tok_id */ + + inbuf.data = (char *)unwrapped_in.data; + inbuf.length = unwrapped_in.length; + ret = krb5_rd_rep(gensec_krb5_state->smb_krb5_context->krb5_context, + gensec_krb5_state->auth_context, + &inbuf, &repl); + if (ret) { + DEBUG(1,("krb5_rd_rep (mutual authentication) failed (%s)\n", + smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, out_mem_ctx))); + dump_data_pw("Mutual authentication message:\n", (uint8_t *)inbuf.data, inbuf.length); + nt_status = NT_STATUS_ACCESS_DENIED; + } else { + *out = data_blob(NULL, 0); + nt_status = NT_STATUS_OK; + gensec_krb5_state->state_position = GENSEC_KRB5_DONE; + } + if (repl) { + krb5_free_ap_rep_enc_part(gensec_krb5_state->smb_krb5_context->krb5_context, repl); + } + return nt_status; + } + + case GENSEC_KRB5_SERVER_START: + { + DATA_BLOB unwrapped_in; + DATA_BLOB unwrapped_out = data_blob(NULL, 0); + krb5_data inbuf, outbuf; + uint8_t tok_id[2]; + struct keytab_container *keytab; + krb5_principal server_in_keytab; + const char *error_string; + enum credentials_obtained obtained; + + if (!in.data) { + return NT_STATUS_INVALID_PARAMETER; + } + + /* Grab the keytab, however generated */ + ret = cli_credentials_get_keytab(gensec_get_credentials(gensec_security), + gensec_security->settings->lp_ctx, &keytab); + if (ret) { + return NT_STATUS_CANT_ACCESS_DOMAIN_INFO; + } + + /* This ensures we lookup the correct entry in that + * keytab. A NULL principal is acceptable, and means + * that the krb5 libs should search the keytab at + * accept time for any matching key */ + ret = principal_from_credentials(out_mem_ctx, gensec_get_credentials(gensec_security), + gensec_krb5_state->smb_krb5_context, + &server_in_keytab, &obtained, &error_string); + + if (ret) { + DEBUG(2,("Failed to make credentials from principal: %s\n", error_string)); + return NT_STATUS_CANT_ACCESS_DOMAIN_INFO; + } + + if (keytab->password_based || obtained < CRED_SPECIFIED) { + /* + * Use match-by-key in this case (matches + * cli_credentials_get_server_gss_creds() + * behaviour). No need to free the memory, + * this is handled with a talloc destructor. + */ + server_in_keytab = NULL; + } + + /* Parse the GSSAPI wrapping, if it's there... (win2k3 allows it to be omited) */ + if (gensec_krb5_state->gssapi + && gensec_gssapi_parse_krb5_wrap(out_mem_ctx, &in, &unwrapped_in, tok_id)) { + inbuf.data = (char *)unwrapped_in.data; + inbuf.length = unwrapped_in.length; + } else { + inbuf.data = (char *)in.data; + inbuf.length = in.length; + } + + ret = smb_krb5_rd_req_decoded(gensec_krb5_state->smb_krb5_context->krb5_context, + &gensec_krb5_state->auth_context, + &inbuf, + keytab->keytab, + server_in_keytab, + &outbuf, + &gensec_krb5_state->ticket, + &gensec_krb5_state->keyblock); + + if (ret) { + DBG_WARNING("smb_krb5_rd_req_decoded failed\n"); + return NT_STATUS_LOGON_FAILURE; + } + unwrapped_out.data = (uint8_t *)outbuf.data; + unwrapped_out.length = outbuf.length; + gensec_krb5_state->state_position = GENSEC_KRB5_DONE; + /* wrap that up in a nice GSS-API wrapping */ + if (gensec_krb5_state->gssapi) { + *out = gensec_gssapi_gen_krb5_wrap(out_mem_ctx, &unwrapped_out, TOK_ID_KRB_AP_REP); + } else { + *out = data_blob_talloc(out_mem_ctx, outbuf.data, outbuf.length); + } + smb_krb5_free_data_contents(gensec_krb5_state->smb_krb5_context->krb5_context, + &outbuf); + return NT_STATUS_OK; + } + + case GENSEC_KRB5_DONE: + default: + /* Asking too many times... */ + return NT_STATUS_INVALID_PARAMETER; + } +} + +struct gensec_krb5_update_state { + NTSTATUS status; + DATA_BLOB out; +}; + +static struct tevent_req *gensec_krb5_update_send(TALLOC_CTX *mem_ctx, + struct tevent_context *ev, + struct gensec_security *gensec_security, + const DATA_BLOB in) +{ + struct tevent_req *req = NULL; + struct gensec_krb5_update_state *state = NULL; + NTSTATUS status; + + req = tevent_req_create(mem_ctx, &state, + struct gensec_krb5_update_state); + if (req == NULL) { + return NULL; + } + + status = gensec_krb5_update_internal(gensec_security, + state, ev, in, + &state->out); + state->status = status; + if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) { + tevent_req_done(req); + return tevent_req_post(req, ev); + } + if (tevent_req_nterror(req, status)) { + return tevent_req_post(req, ev); + } + + tevent_req_done(req); + return tevent_req_post(req, ev); +} + +static NTSTATUS gensec_krb5_update_recv(struct tevent_req *req, + TALLOC_CTX *out_mem_ctx, + DATA_BLOB *out) +{ + struct gensec_krb5_update_state *state = + tevent_req_data(req, + struct gensec_krb5_update_state); + NTSTATUS status; + + *out = data_blob_null; + + if (tevent_req_is_nterror(req, &status)) { + tevent_req_received(req); + return status; + } + + *out = state->out; + talloc_steal(out_mem_ctx, state->out.data); + status = state->status; + tevent_req_received(req); + return status; +} + +static NTSTATUS gensec_krb5_session_key(struct gensec_security *gensec_security, + TALLOC_CTX *mem_ctx, + DATA_BLOB *session_key) +{ + struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context; + krb5_auth_context auth_context = gensec_krb5_state->auth_context; + krb5_error_code err = -1; + bool remote = false; + bool ok; + + if (gensec_krb5_state->state_position != GENSEC_KRB5_DONE) { + return NT_STATUS_NO_USER_SESSION_KEY; + } + + switch (gensec_security->gensec_role) { + case GENSEC_CLIENT: + remote = false; + break; + case GENSEC_SERVER: + remote = true; + break; + } + + ok = smb_krb5_get_smb_session_key(mem_ctx, + context, + auth_context, + session_key, + remote); + if (!ok) { + DEBUG(10, ("KRB5 error getting session key %d\n", err)); + return NT_STATUS_NO_USER_SESSION_KEY; + } + + return NT_STATUS_OK; +} + +#ifdef SAMBA4_USES_HEIMDAL +static NTSTATUS gensec_krb5_session_info(struct gensec_security *gensec_security, + TALLOC_CTX *mem_ctx, + struct auth_session_info **_session_info) +{ + NTSTATUS nt_status = NT_STATUS_UNSUCCESSFUL; + struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context; + struct auth_session_info *session_info = NULL; + + krb5_principal client_principal; + char *principal_string = NULL; + + DATA_BLOB pac_blob, *pac_blob_ptr = NULL; + krb5_data pac_data; + + krb5_error_code ret; + + TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); + if (!tmp_ctx) { + return NT_STATUS_NO_MEMORY; + } + + ret = krb5_ticket_get_client(context, gensec_krb5_state->ticket, &client_principal); + if (ret) { + DEBUG(5, ("krb5_ticket_get_client failed to get client principal: %s\n", + smb_get_krb5_error_message(context, + ret, tmp_ctx))); + talloc_free(tmp_ctx); + return NT_STATUS_NO_MEMORY; + } + + ret = krb5_unparse_name(gensec_krb5_state->smb_krb5_context->krb5_context, + client_principal, &principal_string); + if (ret) { + DEBUG(1, ("Unable to parse client principal: %s\n", + smb_get_krb5_error_message(context, + ret, tmp_ctx))); + krb5_free_principal(context, client_principal); + talloc_free(tmp_ctx); + return NT_STATUS_NO_MEMORY; + } + + ret = krb5_ticket_get_authorization_data_type(context, gensec_krb5_state->ticket, + KRB5_AUTHDATA_WIN2K_PAC, + &pac_data); + + if (ret) { + /* NO pac */ + DEBUG(5, ("krb5_ticket_get_authorization_data_type failed to find PAC: %s\n", + smb_get_krb5_error_message(context, + ret, tmp_ctx))); + } else { + /* Found pac */ + pac_blob = data_blob_talloc(tmp_ctx, pac_data.data, pac_data.length); + smb_krb5_free_data_contents(context, &pac_data); + if (!pac_blob.data) { + free(principal_string); + krb5_free_principal(context, client_principal); + talloc_free(tmp_ctx); + return NT_STATUS_NO_MEMORY; + } + + /* decode and verify the pac */ + nt_status = kerberos_decode_pac(gensec_krb5_state, + pac_blob, + gensec_krb5_state->smb_krb5_context->krb5_context, + NULL, gensec_krb5_state->keyblock, + client_principal, + gensec_krb5_state->ticket->ticket.authtime, NULL); + + if (!NT_STATUS_IS_OK(nt_status)) { + free(principal_string); + krb5_free_principal(context, client_principal); + talloc_free(tmp_ctx); + return nt_status; + } + + pac_blob_ptr = &pac_blob; + } + + nt_status = gensec_generate_session_info_pac(tmp_ctx, + gensec_security, + gensec_krb5_state->smb_krb5_context, + pac_blob_ptr, principal_string, + gensec_get_remote_address(gensec_security), + &session_info); + + free(principal_string); + krb5_free_principal(context, client_principal); + + if (!NT_STATUS_IS_OK(nt_status)) { + talloc_free(tmp_ctx); + return nt_status; + } + + nt_status = gensec_krb5_session_key(gensec_security, session_info, &session_info->session_key); + + if (!NT_STATUS_IS_OK(nt_status)) { + talloc_free(tmp_ctx); + return nt_status; + } + + *_session_info = talloc_steal(mem_ctx, session_info); + + talloc_free(tmp_ctx); + return NT_STATUS_OK; +} +#else /* MIT KERBEROS */ +static NTSTATUS gensec_krb5_session_info(struct gensec_security *gensec_security, + TALLOC_CTX *mem_ctx, + struct auth_session_info **psession_info) +{ + NTSTATUS status = NT_STATUS_UNSUCCESSFUL; + struct gensec_krb5_state *gensec_krb5_state = + (struct gensec_krb5_state *)gensec_security->private_data; + krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context; + struct auth_session_info *session_info = NULL; + + krb5_principal client_principal; + char *principal_string = NULL; + + krb5_authdata **auth_pac_data = NULL; + DATA_BLOB pac_blob, *pac_blob_ptr = NULL; + + krb5_error_code code; + + TALLOC_CTX *tmp_ctx; + + tmp_ctx = talloc_new(mem_ctx); + if (tmp_ctx == NULL) { + return NT_STATUS_NO_MEMORY; + } + + code = krb5_copy_principal(context, + gensec_krb5_state->ticket->enc_part2->client, + &client_principal); + if (code != 0) { + DBG_INFO("krb5_copy_principal failed to copy client " + "principal: %s\n", + smb_get_krb5_error_message(context, code, tmp_ctx)); + talloc_free(tmp_ctx); + return NT_STATUS_NO_MEMORY; + } + + code = krb5_unparse_name(context, client_principal, &principal_string); + if (code != 0) { + DBG_WARNING("Unable to parse client principal: %s\n", + smb_get_krb5_error_message(context, code, tmp_ctx)); + krb5_free_principal(context, client_principal); + talloc_free(tmp_ctx); + return NT_STATUS_NO_MEMORY; + } + + code = krb5_find_authdata(context, + gensec_krb5_state->ticket->enc_part2->authorization_data, + NULL, + KRB5_AUTHDATA_WIN2K_PAC, + &auth_pac_data); + if (code != 0) { + /* NO pac */ + DBG_INFO("krb5_find_authdata failed to find PAC: %s\n", + smb_get_krb5_error_message(context, code, tmp_ctx)); + } else { + krb5_timestamp ticket_authtime = + gensec_krb5_state->ticket->enc_part2->times.authtime; + + /* Found pac */ + pac_blob = data_blob_talloc(tmp_ctx, + auth_pac_data[0]->contents, + auth_pac_data[0]->length); + krb5_free_authdata(context, auth_pac_data); + if (pac_blob.data == NULL) { + free(principal_string); + krb5_free_principal(context, client_principal); + talloc_free(tmp_ctx); + return NT_STATUS_NO_MEMORY; + } + + /* decode and verify the pac */ + status = kerberos_decode_pac(gensec_krb5_state, + pac_blob, + context, + NULL, + gensec_krb5_state->keyblock, + client_principal, + ticket_authtime, + NULL); + + if (!NT_STATUS_IS_OK(status)) { + free(principal_string); + krb5_free_principal(context, client_principal); + talloc_free(tmp_ctx); + return status; + } + + pac_blob_ptr = &pac_blob; + } + krb5_free_principal(context, client_principal); + + status = gensec_generate_session_info_pac(tmp_ctx, + gensec_security, + gensec_krb5_state->smb_krb5_context, + pac_blob_ptr, + principal_string, + gensec_get_remote_address(gensec_security), + &session_info); + SAFE_FREE(principal_string); + if (!NT_STATUS_IS_OK(status)) { + talloc_free(tmp_ctx); + return status; + } + + status = gensec_krb5_session_key(gensec_security, + session_info, + &session_info->session_key); + if (!NT_STATUS_IS_OK(status)) { + talloc_free(tmp_ctx); + return status; + } + + *psession_info = talloc_steal(mem_ctx, session_info); + talloc_free(tmp_ctx); + + return NT_STATUS_OK; +} +#endif /* SAMBA4_USES_HEIMDAL */ + +static NTSTATUS gensec_krb5_wrap(struct gensec_security *gensec_security, + TALLOC_CTX *mem_ctx, + const DATA_BLOB *in, + DATA_BLOB *out) +{ + struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context; + krb5_auth_context auth_context = gensec_krb5_state->auth_context; + krb5_error_code ret; + krb5_data input, output; + input.length = in->length; + input.data = (char *)in->data; + + if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) { + ret = krb5_mk_priv(context, auth_context, &input, &output, NULL); + if (ret) { + DEBUG(1, ("krb5_mk_priv failed: %s\n", + smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, + ret, mem_ctx))); + return NT_STATUS_ACCESS_DENIED; + } + *out = data_blob_talloc(mem_ctx, output.data, output.length); + + smb_krb5_free_data_contents(context, &output); + } else { + return NT_STATUS_ACCESS_DENIED; + } + return NT_STATUS_OK; +} + +static NTSTATUS gensec_krb5_unwrap(struct gensec_security *gensec_security, + TALLOC_CTX *mem_ctx, + const DATA_BLOB *in, + DATA_BLOB *out) +{ + struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context; + krb5_auth_context auth_context = gensec_krb5_state->auth_context; + krb5_error_code ret; + krb5_data input, output; + krb5_replay_data replay; + input.length = in->length; + input.data = (char *)in->data; + + if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) { + ret = krb5_rd_priv(context, auth_context, &input, &output, &replay); + if (ret) { + DEBUG(1, ("krb5_rd_priv failed: %s\n", + smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, + ret, mem_ctx))); + return NT_STATUS_ACCESS_DENIED; + } + *out = data_blob_talloc(mem_ctx, output.data, output.length); + + smb_krb5_free_data_contents(context, &output); + } else { + return NT_STATUS_ACCESS_DENIED; + } + return NT_STATUS_OK; +} + +static bool gensec_krb5_have_feature(struct gensec_security *gensec_security, + uint32_t feature) +{ + struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data; + if (feature & GENSEC_FEATURE_SESSION_KEY) { + return true; + } + if (gensec_krb5_state->gssapi) { + return false; + } + + /* + * krb5_mk_priv provides SIGN and SEAL + */ + if (feature & GENSEC_FEATURE_SIGN) { + return true; + } + if (feature & GENSEC_FEATURE_SEAL) { + return true; + } + + return false; +} + +static const char *gensec_krb5_final_auth_type(struct gensec_security *gensec_security) +{ + return GENSEC_FINAL_AUTH_TYPE_KRB5; +} + +static const char *gensec_krb5_oids[] = { + GENSEC_OID_KERBEROS5, + GENSEC_OID_KERBEROS5_OLD, + NULL +}; + +static const struct gensec_security_ops gensec_fake_gssapi_krb5_security_ops = { + .name = "fake_gssapi_krb5", + .auth_type = DCERPC_AUTH_TYPE_KRB5, + .oid = gensec_krb5_oids, + .client_start = gensec_fake_gssapi_krb5_client_start, + .server_start = gensec_fake_gssapi_krb5_server_start, + .update_send = gensec_krb5_update_send, + .update_recv = gensec_krb5_update_recv, + .magic = gensec_magic_check_krb5_oid, + .session_key = gensec_krb5_session_key, + .session_info = gensec_krb5_session_info, + .have_feature = gensec_krb5_have_feature, + .final_auth_type = gensec_krb5_final_auth_type, + .enabled = false, + .kerberos = true, + .priority = GENSEC_KRB5, +}; + +static const struct gensec_security_ops gensec_krb5_security_ops = { + .name = "krb5", + .client_start = gensec_krb5_client_start, + .server_start = gensec_krb5_server_start, + .update_send = gensec_krb5_update_send, + .update_recv = gensec_krb5_update_recv, + .session_key = gensec_krb5_session_key, + .session_info = gensec_krb5_session_info, + .have_feature = gensec_krb5_have_feature, + .wrap = gensec_krb5_wrap, + .unwrap = gensec_krb5_unwrap, + .final_auth_type = gensec_krb5_final_auth_type, + .enabled = true, + .kerberos = true, + .priority = GENSEC_KRB5 +}; + +_PUBLIC_ NTSTATUS gensec_krb5_init(TALLOC_CTX *ctx) +{ + NTSTATUS ret; + + ret = gensec_register(ctx, &gensec_krb5_security_ops); + if (!NT_STATUS_IS_OK(ret)) { + DEBUG(0,("Failed to register '%s' gensec backend!\n", + gensec_krb5_security_ops.name)); + return ret; + } + + ret = gensec_register(ctx, &gensec_fake_gssapi_krb5_security_ops); + if (!NT_STATUS_IS_OK(ret)) { + DEBUG(0,("Failed to register '%s' gensec backend!\n", + gensec_fake_gssapi_krb5_security_ops.name)); + return ret; + } + + return ret; +} |