From 1d779bdbb21f50c1f638e1abfa732807d32d6887 Mon Sep 17 00:00:00 2001 From: Simo Sorce Date: Sat, 2 Aug 2014 10:31:20 -0400 Subject: Remove custom password change code in libads Use standard libkrb5 calls instead. Signed-off-by: Simo Sorce Reviewed-by: Guenther Deschner Reviewed-by: Andreas Schneider Reviewed-by: Andrew Bartlet --- source3/libads/krb5_setpw.c | 614 +++++--------------------------------------- 1 file changed, 59 insertions(+), 555 deletions(-) (limited to 'source3/libads') diff --git a/source3/libads/krb5_setpw.c b/source3/libads/krb5_setpw.c index 4286c3b6215..c7bf0ec5373 100644 --- a/source3/libads/krb5_setpw.c +++ b/source3/libads/krb5_setpw.c @@ -25,14 +25,7 @@ #ifdef HAVE_KRB5 -#define DEFAULT_KPASSWD_PORT 464 - -#define KRB5_KPASSWD_VERS_CHANGEPW 1 - -#define KRB5_KPASSWD_VERS_SETPW 0xff80 -#define KRB5_KPASSWD_VERS_SETPW_ALT 2 - -/* Those are defined by kerberos-set-passwd-02.txt and are probably +/* Those are defined by kerberos-set-passwd-02.txt and are probably * not supported by M$ implementation */ #define KRB5_KPASSWD_POLICY_REJECT 8 #define KRB5_KPASSWD_BAD_PRINCIPAL 9 @@ -43,208 +36,7 @@ * requests - valid response for CHPW v2 replies. */ -#define krb5_is_krb_error(packet) \ - ( packet && packet->length && (((char *)packet->data)[0] == 0x7e || ((char *)packet->data)[0] == 0x5e)) - -/* This implements kerberos password change protocol as specified in - * kerb-chg-password-02.txt and kerberos-set-passwd-02.txt - * as well as microsoft version of the protocol - * as specified in kerberos-set-passwd-00.txt - */ -static DATA_BLOB encode_krb5_setpw(const char *principal, const char *password) -{ - char* princ_part1 = NULL; - char* princ_part2 = NULL; - char* realm = NULL; - char* c; - char* princ; - - ASN1_DATA *req; - DATA_BLOB ret; - - - princ = SMB_STRDUP(principal); - - if ((c = strchr_m(princ, '/')) == NULL) { - c = princ; - } else { - *c = '\0'; - c++; - princ_part1 = princ; - } - - princ_part2 = c; - - if ((c = strchr_m(c, '@')) != NULL) { - *c = '\0'; - c++; - realm = c; - } else { - /* We must have a realm component. */ - return data_blob_null; - } - - req = asn1_init(talloc_tos()); - if (req == NULL) { - return data_blob_null; - } - - asn1_push_tag(req, ASN1_SEQUENCE(0)); - asn1_push_tag(req, ASN1_CONTEXT(0)); - asn1_write_OctetString(req, password, strlen(password)); - asn1_pop_tag(req); - - asn1_push_tag(req, ASN1_CONTEXT(1)); - asn1_push_tag(req, ASN1_SEQUENCE(0)); - - asn1_push_tag(req, ASN1_CONTEXT(0)); - asn1_write_Integer(req, 1); - asn1_pop_tag(req); - - asn1_push_tag(req, ASN1_CONTEXT(1)); - asn1_push_tag(req, ASN1_SEQUENCE(0)); - - if (princ_part1) { - asn1_write_GeneralString(req, princ_part1); - } - - asn1_write_GeneralString(req, princ_part2); - asn1_pop_tag(req); - asn1_pop_tag(req); - asn1_pop_tag(req); - asn1_pop_tag(req); - - asn1_push_tag(req, ASN1_CONTEXT(2)); - asn1_write_GeneralString(req, realm); - asn1_pop_tag(req); - asn1_pop_tag(req); - - ret = data_blob(req->data, req->length); - asn1_free(req); - - free(princ); - - return ret; -} - -static krb5_error_code build_kpasswd_request(uint16 pversion, - krb5_context context, - krb5_auth_context auth_context, - krb5_data *ap_req, - const char *princ, - const char *passwd, - bool use_tcp, - krb5_data *packet) -{ - krb5_error_code ret; - krb5_data cipherpw; - krb5_data encoded_setpw; - krb5_replay_data replay; - char *p, *msg_start; - DATA_BLOB setpw; - unsigned int msg_length; - - ret = krb5_auth_con_setflags(context, - auth_context,KRB5_AUTH_CONTEXT_DO_SEQUENCE); - if (ret) { - DEBUG(1,("krb5_auth_con_setflags failed (%s)\n", - error_message(ret))); - return ret; - } - - /* handle protocol differences in chpw and setpw */ - if (pversion == KRB5_KPASSWD_VERS_CHANGEPW) - setpw = data_blob(passwd, strlen(passwd)); - else if (pversion == KRB5_KPASSWD_VERS_SETPW || - pversion == KRB5_KPASSWD_VERS_SETPW_ALT) - setpw = encode_krb5_setpw(princ, passwd); - else - return EINVAL; - - if (setpw.data == NULL || setpw.length == 0) { - return EINVAL; - } - - encoded_setpw.data = (char *)setpw.data; - encoded_setpw.length = setpw.length; - - ret = krb5_mk_priv(context, auth_context, - &encoded_setpw, &cipherpw, &replay); - - data_blob_free(&setpw); /*from 'encode_krb5_setpw(...)' */ - - if (ret) { - DEBUG(1,("krb5_mk_priv failed (%s)\n", error_message(ret))); - return ret; - } - - packet->data = (char *)SMB_MALLOC(ap_req->length + cipherpw.length + (use_tcp ? 10 : 6 )); - if (!packet->data) - return -1; - - - - /* see the RFC for details */ - - msg_start = p = ((char *)packet->data) + (use_tcp ? 4 : 0); - p += 2; - RSSVAL(p, 0, pversion); - p += 2; - RSSVAL(p, 0, ap_req->length); - p += 2; - memcpy(p, ap_req->data, ap_req->length); - p += ap_req->length; - memcpy(p, cipherpw.data, cipherpw.length); - p += cipherpw.length; - packet->length = PTR_DIFF(p,packet->data); - msg_length = PTR_DIFF(p,msg_start); - - if (use_tcp) { - RSIVAL(packet->data, 0, msg_length); - } - RSSVAL(msg_start, 0, msg_length); - - free(cipherpw.data); /* from 'krb5_mk_priv(...)' */ - - return 0; -} - -static const struct kpasswd_errors { - int result_code; - const char *error_string; -} kpasswd_errors[] = { - {KRB5_KPASSWD_MALFORMED, "Malformed request error"}, - {KRB5_KPASSWD_HARDERROR, "Server error"}, - {KRB5_KPASSWD_AUTHERROR, "Authentication error"}, - {KRB5_KPASSWD_SOFTERROR, "Password change rejected"}, - {KRB5_KPASSWD_ACCESSDENIED, "Client does not have proper authorization"}, - {KRB5_KPASSWD_BAD_VERSION, "Protocol version not supported"}, - {KRB5_KPASSWD_INITIAL_FLAG_NEEDED, "Authorization ticket must have initial flag set"}, - {KRB5_KPASSWD_POLICY_REJECT, "Password rejected due to policy requirements"}, - {KRB5_KPASSWD_BAD_PRINCIPAL, "Target principal does not exist"}, - {KRB5_KPASSWD_ETYPE_NOSUPP, "Unsupported encryption type"}, - {0, NULL} -}; - -static krb5_error_code setpw_result_code_string(krb5_context context, - int result_code, - const char **code_string) -{ - unsigned int idx = 0; - - while (kpasswd_errors[idx].error_string != NULL) { - if (kpasswd_errors[idx].result_code == - result_code) { - *code_string = kpasswd_errors[idx].error_string; - return 0; - } - idx++; - } - *code_string = "Password change failed"; - return (0); -} - - krb5_error_code kpasswd_err_to_krb5_err(krb5_error_code res_code) +static krb5_error_code kpasswd_err_to_krb5_err(krb5_error_code res_code) { switch(res_code) { case KRB5_KPASSWD_ACCESSDENIED: @@ -263,379 +55,72 @@ static krb5_error_code setpw_result_code_string(krb5_context context, return KRB5KRB_ERR_GENERIC; } } -static krb5_error_code parse_setpw_reply(krb5_context context, - bool use_tcp, - krb5_auth_context auth_context, - krb5_data *packet) -{ - krb5_data ap_rep; - char *p; - int vnum, ret, res_code; - krb5_data cipherresult; - krb5_data clearresult; - krb5_ap_rep_enc_part *ap_rep_enc; - krb5_replay_data replay; - unsigned int msg_length = packet->length; - - - if (packet->length < (use_tcp ? 8 : 4)) { - return KRB5KRB_AP_ERR_MODIFIED; - } - - p = (char *)packet->data; - /* - ** see if it is an error - */ - if (krb5_is_krb_error(packet)) { - - ret = handle_krberror_packet(context, packet); - if (ret) { - return ret; - } - } - - - /* tcp... */ - if (use_tcp) { - msg_length -= 4; - if (RIVAL(p, 0) != msg_length) { - DEBUG(1,("Bad TCP packet length (%d/%d) from kpasswd server\n", - RIVAL(p, 0), msg_length)); - return KRB5KRB_AP_ERR_MODIFIED; - } - - p += 4; - } - - if (RSVAL(p, 0) != msg_length) { - DEBUG(1,("Bad packet length (%d/%d) from kpasswd server\n", - RSVAL(p, 0), msg_length)); - return KRB5KRB_AP_ERR_MODIFIED; - } - - p += 2; - - vnum = RSVAL(p, 0); p += 2; - - /* FIXME: According to standard there is only one type of reply */ - if (vnum != KRB5_KPASSWD_VERS_SETPW && - vnum != KRB5_KPASSWD_VERS_SETPW_ALT && - vnum != KRB5_KPASSWD_VERS_CHANGEPW) { - DEBUG(1,("Bad vnum (%d) from kpasswd server\n", vnum)); - return KRB5KDC_ERR_BAD_PVNO; - } - - ap_rep.length = RSVAL(p, 0); p += 2; - - if (p + ap_rep.length >= (char *)packet->data + packet->length) { - DEBUG(1,("ptr beyond end of packet from kpasswd server\n")); - return KRB5KRB_AP_ERR_MODIFIED; - } - - if (ap_rep.length == 0) { - DEBUG(1,("got unencrypted setpw result?!\n")); - return KRB5KRB_AP_ERR_MODIFIED; - } - - /* verify ap_rep */ - ap_rep.data = p; - p += ap_rep.length; - - ret = krb5_rd_rep(context, auth_context, &ap_rep, &ap_rep_enc); - if (ret) { - DEBUG(1,("failed to rd setpw reply (%s)\n", error_message(ret))); - return KRB5KRB_AP_ERR_MODIFIED; - } - - krb5_free_ap_rep_enc_part(context, ap_rep_enc); - - cipherresult.data = p; - cipherresult.length = ((char *)packet->data + packet->length) - p; - - ret = krb5_rd_priv(context, auth_context, &cipherresult, &clearresult, - &replay); - if (ret) { - DEBUG(1,("failed to decrypt setpw reply (%s)\n", error_message(ret))); - return KRB5KRB_AP_ERR_MODIFIED; - } - - if (clearresult.length < 2) { - free(clearresult.data); - ret = KRB5KRB_AP_ERR_MODIFIED; - return KRB5KRB_AP_ERR_MODIFIED; - } - - p = (char *)clearresult.data; - - res_code = RSVAL(p, 0); - - free(clearresult.data); - - if ((res_code < KRB5_KPASSWD_SUCCESS) || - (res_code > KRB5_KPASSWD_ETYPE_NOSUPP)) { - return KRB5KRB_AP_ERR_MODIFIED; - } - - if (res_code == KRB5_KPASSWD_SUCCESS) { - return 0; - } else { - const char *errstr; - setpw_result_code_string(context, res_code, &errstr); - DEBUG(1, ("Error changing password: %s (%d)\n", errstr, res_code)); - - return kpasswd_err_to_krb5_err(res_code); - } -} - -static ADS_STATUS do_krb5_kpasswd_request(krb5_context context, - const char *kdc_host, - uint16 pversion, - krb5_creds *credsp, - const char *princ, - const char *newpw) -{ - krb5_auth_context auth_context = NULL; - krb5_data ap_req, chpw_req, chpw_rep; - int ret, sock; - socklen_t addr_len; - struct sockaddr_storage remote_addr, local_addr; - struct sockaddr_storage addr; - krb5_address local_kaddr, remote_kaddr; - bool use_tcp = False; - - - if (!interpret_string_addr(&addr, kdc_host, 0)) { - } - - ret = krb5_mk_req_extended(context, &auth_context, AP_OPTS_USE_SUBKEY, - NULL, credsp, &ap_req); - if (ret) { - DEBUG(1,("krb5_mk_req_extended failed (%s)\n", error_message(ret))); - return ADS_ERROR_KRB5(ret); - } - - do { - - if (!use_tcp) { - - sock = open_udp_socket(kdc_host, DEFAULT_KPASSWD_PORT); - if (sock == -1) { - int rc = errno; - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("failed to open kpasswd socket to %s " - "(%s)\n", kdc_host, strerror(errno))); - return ADS_ERROR_SYSTEM(rc); - } - } else { - NTSTATUS status; - status = open_socket_out(&addr, DEFAULT_KPASSWD_PORT, - LONG_CONNECT_TIMEOUT, &sock); - if (!NT_STATUS_IS_OK(status)) { - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("failed to open kpasswd socket to %s " - "(%s)\n", kdc_host, - nt_errstr(status))); - return ADS_ERROR_NT(status); - } - } - - addr_len = sizeof(remote_addr); - if (getpeername(sock, (struct sockaddr *)&remote_addr, &addr_len) != 0) { - close(sock); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("getpeername() failed (%s)\n", error_message(errno))); - return ADS_ERROR_SYSTEM(errno); - } - addr_len = sizeof(local_addr); - if (getsockname(sock, (struct sockaddr *)&local_addr, &addr_len) != 0) { - close(sock); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("getsockname() failed (%s)\n", error_message(errno))); - return ADS_ERROR_SYSTEM(errno); - } - if (!setup_kaddr(&remote_kaddr, &remote_addr) || - !setup_kaddr(&local_kaddr, &local_addr)) { - DEBUG(1,("do_krb5_kpasswd_request: " - "Failed to setup addresses.\n")); - close(sock); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - errno = EINVAL; - return ADS_ERROR_SYSTEM(EINVAL); - } - - ret = krb5_auth_con_setaddrs(context, auth_context, &local_kaddr, NULL); - if (ret) { - close(sock); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("krb5_auth_con_setaddrs failed (%s)\n", error_message(ret))); - return ADS_ERROR_KRB5(ret); - } - - ret = build_kpasswd_request(pversion, context, auth_context, &ap_req, - princ, newpw, use_tcp, &chpw_req); - if (ret) { - close(sock); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("build_setpw_request failed (%s)\n", error_message(ret))); - return ADS_ERROR_KRB5(ret); - } - - ret = write(sock, chpw_req.data, chpw_req.length); - if (ret != chpw_req.length) { - close(sock); - SAFE_FREE(chpw_req.data); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("send of chpw failed (%s)\n", strerror(errno))); - return ADS_ERROR_SYSTEM(errno); - } - - SAFE_FREE(chpw_req.data); - - chpw_rep.length = 1500; - chpw_rep.data = (char *) SMB_MALLOC(chpw_rep.length); - if (!chpw_rep.data) { - close(sock); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("send of chpw failed (%s)\n", strerror(errno))); - errno = ENOMEM; - return ADS_ERROR_SYSTEM(errno); - } - - ret = read(sock, chpw_rep.data, chpw_rep.length); - if (ret < 0) { - close(sock); - SAFE_FREE(chpw_rep.data); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("recv of chpw reply failed (%s)\n", strerror(errno))); - return ADS_ERROR_SYSTEM(errno); - } - - close(sock); - chpw_rep.length = ret; - - ret = krb5_auth_con_setaddrs(context, auth_context, NULL,&remote_kaddr); - if (ret) { - SAFE_FREE(chpw_rep.data); - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("krb5_auth_con_setaddrs on reply failed (%s)\n", - error_message(ret))); - return ADS_ERROR_KRB5(ret); - } - - ret = parse_setpw_reply(context, use_tcp, auth_context, &chpw_rep); - SAFE_FREE(chpw_rep.data); - - if (ret) { - - if (ret == KRB5KRB_ERR_RESPONSE_TOO_BIG && !use_tcp) { - DEBUG(5, ("Trying setpw with TCP!!!\n")); - use_tcp = True; - continue; - } - - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - DEBUG(1,("parse_setpw_reply failed (%s)\n", - error_message(ret))); - return ADS_ERROR_KRB5(ret); - } - - SAFE_FREE(ap_req.data); - krb5_auth_con_free(context, auth_context); - } while ( ret ); - - return ADS_SUCCESS; -} - -ADS_STATUS ads_krb5_set_password(const char *kdc_host, const char *princ, +ADS_STATUS ads_krb5_set_password(const char *kdc_host, const char *principal, const char *newpw, int time_offset) { ADS_STATUS aret; krb5_error_code ret = 0; krb5_context context = NULL; - char *realm = NULL; - unsigned int realm_len = 0; - krb5_creds creds, *credsp = NULL; + krb5_principal princ = NULL; krb5_ccache ccache = NULL; + int result_code; + krb5_data result_code_string = { 0 }; + krb5_data result_string = { 0 }; - ZERO_STRUCT(creds); - initialize_krb5_error_table(); ret = krb5_init_context(&context); if (ret) { DEBUG(1,("Failed to init krb5 context (%s)\n", error_message(ret))); return ADS_ERROR_KRB5(ret); } - + + if (principal) { + ret = smb_krb5_parse_name(context, principal, &princ); + if (ret) { + krb5_free_context(context); + DEBUG(1, ("Failed to parse %s (%s)\n", principal, + error_message(ret))); + return ADS_ERROR_KRB5(ret); + } + } + if (time_offset != 0) { krb5_set_real_time(context, time(NULL) + time_offset, 0); } ret = krb5_cc_default(context, &ccache); if (ret) { + krb5_free_principal(context, princ); krb5_free_context(context); DEBUG(1,("Failed to get default creds (%s)\n", error_message(ret))); return ADS_ERROR_KRB5(ret); } - ret = krb5_cc_get_principal(context, ccache, &creds.client); + ret = krb5_set_password_using_ccache(context, ccache, newpw, princ, + &result_code, + &result_code_string, + &result_string); if (ret) { - krb5_cc_close(context, ccache); - krb5_free_context(context); - DEBUG(1,("Failed to get principal from ccache (%s)\n", - error_message(ret))); - return ADS_ERROR_KRB5(ret); + DEBUG(1, ("krb5_set_password failed (%s)\n", error_message(ret))); + aret = ADS_ERROR_KRB5(ret); + goto done; } - realm = smb_krb5_principal_get_realm(context, creds.client); - realm_len = strlen(realm); - ret = krb5_build_principal(context, - &creds.server, - realm_len, - realm, "kadmin", "changepw", NULL); - free(realm); - ret = krb5_get_credentials(context, 0, ccache, &creds, &credsp); - if (ret) { - krb5_cc_close(context, ccache); - krb5_free_principal(context, creds.client); - krb5_free_principal(context, creds.server); - krb5_free_context(context); - DEBUG(1,("krb5_build_prinipal_ext (%s)\n", error_message(ret))); - return ADS_ERROR_KRB5(ret); + if (result_code != KRB5_KPASSWD_SUCCESS) { + ret = kpasswd_err_to_krb5_err(result_code); + DEBUG(1, ("krb5_set_password failed (%s)\n", error_message(ret))); + aret = ADS_ERROR_KRB5(ret); + goto done; } - - ret = krb5_get_credentials(context, 0, ccache, &creds, &credsp); - if (ret) { - krb5_cc_close(context, ccache); - krb5_free_principal(context, creds.client); - krb5_free_principal(context, creds.server); - krb5_free_context(context); - DEBUG(1,("krb5_get_credentials failed (%s)\n", error_message(ret))); - return ADS_ERROR_KRB5(ret); - } - - /* we might have to call krb5_free_creds(...) from now on ... */ - aret = do_krb5_kpasswd_request(context, kdc_host, - KRB5_KPASSWD_VERS_SETPW, - credsp, princ, newpw); + aret = ADS_SUCCESS; - krb5_free_creds(context, credsp); - krb5_free_principal(context, creds.client); - krb5_free_principal(context, creds.server); +done: + kerberos_free_data_contents(context, &result_code_string); + kerberos_free_data_contents(context, &result_string); + krb5_free_principal(context, princ); krb5_cc_close(context, ccache); krb5_free_context(context); @@ -683,7 +168,10 @@ static ADS_STATUS ads_krb5_chg_password(const char *kdc_host, krb5_get_init_creds_opt opts; krb5_creds creds; char *chpw_princ = NULL, *password; - char *realm = NULL; + const char *realm = NULL; + int result_code; + krb5_data result_code_string = { 0 }; + krb5_data result_string = { 0 }; initialize_krb5_error_table(); ret = krb5_init_context(&context); @@ -734,10 +222,26 @@ static ADS_STATUS ads_krb5_chg_password(const char *kdc_host, return ADS_ERROR_KRB5(ret); } - aret = do_krb5_kpasswd_request(context, kdc_host, - KRB5_KPASSWD_VERS_CHANGEPW, - &creds, principal, newpw); + ret = krb5_change_password(context, &creds, newpw, &result_code, + &result_code_string, &result_string); + if (ret) { + DEBUG(1, ("krb5_change_password failed (%s)\n", error_message(ret))); + aret = ADS_ERROR_KRB5(ret); + goto done; + } + + if (result_code != KRB5_KPASSWD_SUCCESS) { + ret = kpasswd_err_to_krb5_err(result_code); + DEBUG(1, ("krb5_change_password failed (%s)\n", error_message(ret))); + aret = ADS_ERROR_KRB5(ret); + goto done; + } + + aret = ADS_SUCCESS; +done: + kerberos_free_data_contents(context, &result_code_string); + kerberos_free_data_contents(context, &result_string); krb5_free_principal(context, princ); krb5_free_context(context); -- cgit v1.2.1