/* Unix SMB/CIFS implementation. simple kerberos5 routines for active directory Copyright (C) Andrew Tridgell 2001 Copyright (C) Luke Howard 2002-2003 Copyright (C) Andrew Bartlett 2005 Copyright (C) Guenther Deschner 2005-2009 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 . */ #include "includes.h" #include "system/filesys.h" #include "krb5_samba.h" #include "lib/crypto/crypto.h" #include "../libds/common/flags.h" #ifdef HAVE_COM_ERR_H #include #endif /* HAVE_COM_ERR_H */ #ifndef KRB5_AUTHDATA_WIN2K_PAC #define KRB5_AUTHDATA_WIN2K_PAC 128 #endif #ifndef KRB5_AUTHDATA_IF_RELEVANT #define KRB5_AUTHDATA_IF_RELEVANT 1 #endif #ifdef HAVE_KRB5 #define GSSAPI_CHECKSUM 0x8003 /* Checksum type value for Kerberos */ #define GSSAPI_BNDLENGTH 16 /* Bind Length (rfc-1964 pg.3) */ #define GSSAPI_CHECKSUM_SIZE (4+GSSAPI_BNDLENGTH+4) /* Length of bind length, bind field, flags field. */ #define GSS_C_DELEG_FLAG 1 /* MIT krb5 1.7beta3 (in Ubuntu Karmic) is missing the prototype, but still has the symbol */ #if !HAVE_DECL_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE krb5_error_code krb5_auth_con_set_req_cksumtype( krb5_context context, krb5_auth_context auth_context, krb5_cksumtype cksumtype); #endif #if !defined(SMB_MALLOC) #undef malloc #define SMB_MALLOC(s) malloc((s)) #endif #ifndef SMB_STRDUP #define SMB_STRDUP(s) strdup(s) #endif /********************************************************** * MISSING FUNCTIONS **********************************************************/ #if !defined(HAVE_KRB5_SET_DEFAULT_TGS_KTYPES) #if defined(HAVE_KRB5_SET_DEFAULT_TGS_ENCTYPES) /* With MIT kerberos, we should use krb5_set_default_tgs_enctypes in preference * to krb5_set_default_tgs_ktypes. See * http://lists.samba.org/archive/samba-technical/2006-July/048271.html * * If the MIT libraries are not exporting internal symbols, we will end up in * this branch, which is correct. Otherwise we will continue to use the * internal symbol */ krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc) { return krb5_set_default_tgs_enctypes(ctx, enc); } #elif defined(HAVE_KRB5_SET_DEFAULT_IN_TKT_ETYPES) /* Heimdal */ krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc) { return krb5_set_default_in_tkt_etypes(ctx, enc); } #endif /* HAVE_KRB5_SET_DEFAULT_TGS_ENCTYPES */ #endif /* HAVE_KRB5_SET_DEFAULT_TGS_KTYPES */ #if defined(HAVE_KRB5_AUTH_CON_SETKEY) && !defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) krb5_error_code krb5_auth_con_setuseruserkey(krb5_context context, krb5_auth_context auth_context, krb5_keyblock *keyblock) { return krb5_auth_con_setkey(context, auth_context, keyblock); } #endif #if !defined(HAVE_KRB5_FREE_UNPARSED_NAME) void krb5_free_unparsed_name(krb5_context context, char *val) { SAFE_FREE(val); } #endif #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING) && !defined(HAVE_KRB5_PRINC_COMPONENT) const krb5_data *krb5_princ_component(krb5_context context, krb5_principal principal, int i); const krb5_data *krb5_princ_component(krb5_context context, krb5_principal principal, int i) { static krb5_data kdata; kdata.data = discard_const_p(char, krb5_principal_get_comp_string(context, principal, i)); kdata.length = strlen((const char *)kdata.data); return &kdata; } #endif /********************************************************** * WRAPPING FUNCTIONS **********************************************************/ #if defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* HEIMDAL */ /** * @brief Stores the address of a 'struct sockaddr_storage' a krb5_address * * @param[in] paddr A pointer to a 'struct sockaddr_storage to extract the * address from. * * @param[out] pkaddr A Kerberos address to store tha address in. * * @return True on success, false if an error occurred. */ bool smb_krb5_sockaddr_to_kaddr(struct sockaddr_storage *paddr, krb5_address *pkaddr) { memset(pkaddr, '\0', sizeof(krb5_address)); #ifdef HAVE_IPV6 if (paddr->ss_family == AF_INET6) { pkaddr->addr_type = KRB5_ADDRESS_INET6; pkaddr->address.length = sizeof(((struct sockaddr_in6 *)paddr)->sin6_addr); pkaddr->address.data = (char *)&(((struct sockaddr_in6 *)paddr)->sin6_addr); return true; } #endif if (paddr->ss_family == AF_INET) { pkaddr->addr_type = KRB5_ADDRESS_INET; pkaddr->address.length = sizeof(((struct sockaddr_in *)paddr)->sin_addr); pkaddr->address.data = (char *)&(((struct sockaddr_in *)paddr)->sin_addr); return true; } return false; } #elif defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */ /** * @brief Stores the address of a 'struct sockaddr_storage' a krb5_address * * @param[in] paddr A pointer to a 'struct sockaddr_storage to extract the * address from. * * @param[in] pkaddr A Kerberos address to store tha address in. * * @return True on success, false if an error occurred. */ bool smb_krb5_sockaddr_to_kaddr(struct sockaddr_storage *paddr, krb5_address *pkaddr) { memset(pkaddr, '\0', sizeof(krb5_address)); #ifdef HAVE_IPV6 if (paddr->ss_family == AF_INET6) { pkaddr->addrtype = ADDRTYPE_INET6; pkaddr->length = sizeof(((struct sockaddr_in6 *)paddr)->sin6_addr); pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in6 *)paddr)->sin6_addr); return true; } #endif if (paddr->ss_family == AF_INET) { pkaddr->addrtype = ADDRTYPE_INET; pkaddr->length = sizeof(((struct sockaddr_in *)paddr)->sin_addr); pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in *)paddr)->sin_addr); return true; } return false; } #else #error UNKNOWN_ADDRTYPE #endif krb5_error_code smb_krb5_mk_error(krb5_context context, krb5_error_code error_code, const char *e_text, krb5_data *e_data, const krb5_principal client, const krb5_principal server, krb5_data *enc_err) { krb5_error_code code = EINVAL; #ifdef SAMBA4_USES_HEIMDAL code = krb5_mk_error(context, error_code, e_text, e_data, client, server, NULL, /* client_time */ NULL, /* client_usec */ enc_err); #else krb5_principal unspec_server = NULL; krb5_error errpkt; errpkt.ctime = 0; errpkt.cusec = 0; code = krb5_us_timeofday(context, &errpkt.stime, &errpkt.susec); if (code != 0) { return code; } errpkt.error = error_code; errpkt.text.length = 0; if (e_text != NULL) { errpkt.text.length = strlen(e_text); errpkt.text.data = discard_const_p(char, e_text); } errpkt.e_data.magic = KV5M_DATA; errpkt.e_data.length = 0; errpkt.e_data.data = NULL; if (e_data != NULL) { errpkt.e_data = *e_data; } errpkt.client = client; if (server != NULL) { errpkt.server = server; } else { code = smb_krb5_make_principal(context, &unspec_server, "", NULL); if (code != 0) { return code; } errpkt.server = unspec_server; } code = krb5_mk_error(context, &errpkt, enc_err); krb5_free_principal(context, unspec_server); #endif return code; } /** * @brief Create a keyblock based on input parameters * * @param context The krb5_context * @param host_princ The krb5_principal to use * @param salt The optional salt, if omitted, salt is calculated with * the provided principal. * @param password The krb5_data containing the password * @param enctype The krb5_enctype to use for the keyblock generation * @param key The returned krb5_keyblock, caller needs to free with * krb5_free_keyblock(). * * @return krb5_error_code */ int smb_krb5_create_key_from_string(krb5_context context, krb5_const_principal host_princ, krb5_data *salt, krb5_data *password, krb5_enctype enctype, krb5_keyblock *key) { int ret = 0; if (host_princ == NULL && salt == NULL) { return -1; } if ((int)enctype == (int)ENCTYPE_ARCFOUR_HMAC) { TALLOC_CTX *frame = talloc_stackframe(); uint8_t *utf16 = NULL; size_t utf16_size = 0; uint8_t nt_hash[16]; bool ok; ok = convert_string_talloc(frame, CH_UNIX, CH_UTF16LE, password->data, password->length, (void **)&utf16, &utf16_size); if (!ok) { if (errno == 0) { errno = EINVAL; } ret = errno; TALLOC_FREE(frame); return ret; } mdfour(nt_hash, utf16, utf16_size); memset(utf16, 0, utf16_size); ret = smb_krb5_keyblock_init_contents(context, ENCTYPE_ARCFOUR_HMAC, nt_hash, sizeof(nt_hash), key); ZERO_STRUCT(nt_hash); if (ret != 0) { TALLOC_FREE(frame); return ret; } TALLOC_FREE(frame); return 0; } #if defined(HAVE_KRB5_PRINCIPAL2SALT) && defined(HAVE_KRB5_C_STRING_TO_KEY) {/* MIT */ krb5_data _salt; if (salt == NULL) { ret = krb5_principal2salt(context, host_princ, &_salt); if (ret) { DEBUG(1,("krb5_principal2salt failed (%s)\n", error_message(ret))); return ret; } } else { _salt = *salt; } ret = krb5_c_string_to_key(context, enctype, password, &_salt, key); if (salt == NULL) { SAFE_FREE(_salt.data); } } #elif defined(HAVE_KRB5_GET_PW_SALT) && defined(HAVE_KRB5_STRING_TO_KEY_SALT) {/* Heimdal */ krb5_salt _salt; if (salt == NULL) { ret = krb5_get_pw_salt(context, host_princ, &_salt); if (ret) { DEBUG(1,("krb5_get_pw_salt failed (%s)\n", error_message(ret))); return ret; } } else { _salt.saltvalue = *salt; _salt.salttype = KRB5_PW_SALT; } ret = krb5_string_to_key_salt(context, enctype, (const char *)password->data, _salt, key); if (salt == NULL) { krb5_free_salt(context, _salt); } } #else #error UNKNOWN_CREATE_KEY_FUNCTIONS #endif return ret; } /** * @brief Create a salt for a given principal * * @param context The initialized krb5_context * @param host_princ The krb5_principal to create the salt for * @param psalt A pointer to a krb5_data struct * * caller has to free the contents of psalt with smb_krb5_free_data_contents * when function has succeeded * * @return krb5_error_code, returns 0 on success, error code otherwise */ int smb_krb5_get_pw_salt(krb5_context context, krb5_const_principal host_princ, krb5_data *psalt) #if defined(HAVE_KRB5_GET_PW_SALT) /* Heimdal */ { int ret; krb5_salt salt; ret = krb5_get_pw_salt(context, host_princ, &salt); if (ret) { return ret; } psalt->data = salt.saltvalue.data; psalt->length = salt.saltvalue.length; return ret; } #elif defined(HAVE_KRB5_PRINCIPAL2SALT) /* MIT */ { return krb5_principal2salt(context, host_princ, psalt); } #else #error UNKNOWN_SALT_FUNCTIONS #endif /** * @brief This constructs the salt principal used by active directory * * Most Kerberos encryption types require a salt in order to * calculate the long term private key for user/computer object * based on a password. * * The returned _salt_principal is a string in forms like this: * - host/somehost.example.com@EXAMPLE.COM * - SomeAccount@EXAMPLE.COM * - SomePrincipal@EXAMPLE.COM * * This is not the form that's used as salt, it's just * the human readable form. It needs to be converted by * smb_krb5_salt_principal2data(). * * @param[in] realm The realm the user/computer is added too. * * @param[in] sAMAccountName The sAMAccountName attribute of the object. * * @param[in] userPrincipalName The userPrincipalName attribute of the object * or NULL is not available. * * @param[in] uac_flags UF_ACCOUNT_TYPE_MASKed userAccountControl field * * @param[in] mem_ctx The TALLOC_CTX to allocate _salt_principal. * * @param[out] _salt_principal The resulting principal as string. * * @retval 0 Success; otherwise - Kerberos error codes * * @see smb_krb5_salt_principal2data */ int smb_krb5_salt_principal(const char *realm, const char *sAMAccountName, const char *userPrincipalName, uint32_t uac_flags, TALLOC_CTX *mem_ctx, char **_salt_principal) { TALLOC_CTX *frame = talloc_stackframe(); char *upper_realm = NULL; const char *principal = NULL; int principal_len = 0; *_salt_principal = NULL; if (sAMAccountName == NULL) { TALLOC_FREE(frame); return EINVAL; } if (realm == NULL) { TALLOC_FREE(frame); return EINVAL; } if (uac_flags & ~UF_ACCOUNT_TYPE_MASK) { /* * catch callers which still * pass 'true'. */ TALLOC_FREE(frame); return EINVAL; } if (uac_flags == 0) { /* * catch callers which still * pass 'false'. */ TALLOC_FREE(frame); return EINVAL; } upper_realm = strupper_talloc(frame, realm); if (upper_realm == NULL) { TALLOC_FREE(frame); return ENOMEM; } /* Many, many thanks to lukeh@padl.com for this * algorithm, described in his Nov 10 2004 mail to * samba-technical@lists.samba.org */ /* * Determine a salting principal */ if (uac_flags & UF_TRUST_ACCOUNT_MASK) { int computer_len = 0; char *tmp = NULL; computer_len = strlen(sAMAccountName); if (sAMAccountName[computer_len-1] == '$') { computer_len -= 1; } if (uac_flags & UF_INTERDOMAIN_TRUST_ACCOUNT) { principal = talloc_asprintf(frame, "krbtgt/%*.*s", computer_len, computer_len, sAMAccountName); if (principal == NULL) { TALLOC_FREE(frame); return ENOMEM; } } else { tmp = talloc_asprintf(frame, "host/%*.*s.%s", computer_len, computer_len, sAMAccountName, realm); if (tmp == NULL) { TALLOC_FREE(frame); return ENOMEM; } principal = strlower_talloc(frame, tmp); TALLOC_FREE(tmp); if (principal == NULL) { TALLOC_FREE(frame); return ENOMEM; } } principal_len = strlen(principal); } else if (userPrincipalName != NULL) { char *p; principal = userPrincipalName; p = strchr(principal, '@'); if (p != NULL) { principal_len = PTR_DIFF(p, principal); } else { principal_len = strlen(principal); } } else { principal = sAMAccountName; principal_len = strlen(principal); } *_salt_principal = talloc_asprintf(mem_ctx, "%*.*s@%s", principal_len, principal_len, principal, upper_realm); if (*_salt_principal == NULL) { TALLOC_FREE(frame); return ENOMEM; } TALLOC_FREE(frame); return 0; } /** * @brief Converts the salt principal string into the salt data blob * * This function takes a salt_principal as string in forms like this: * - host/somehost.example.com@EXAMPLE.COM * - SomeAccount@EXAMPLE.COM * - SomePrincipal@EXAMPLE.COM * * It generates values like: * - EXAMPLE.COMhost/somehost.example.com * - EXAMPLE.COMSomeAccount * - EXAMPLE.COMSomePrincipal * * @param[in] realm The realm the user/computer is added too. * * @param[in] sAMAccountName The sAMAccountName attribute of the object. * * @param[in] userPrincipalName The userPrincipalName attribute of the object * or NULL is not available. * * @param[in] is_computer The indication of the object includes * objectClass=computer. * * @param[in] mem_ctx The TALLOC_CTX to allocate _salt_principal. * * @param[out] _salt_principal The resulting principal as string. * * @retval 0 Success; otherwise - Kerberos error codes * * @see smb_krb5_salt_principal */ int smb_krb5_salt_principal2data(krb5_context context, const char *salt_principal, TALLOC_CTX *mem_ctx, char **_salt_data) { krb5_error_code ret; krb5_principal salt_princ = NULL; krb5_data salt; *_salt_data = NULL; ret = krb5_parse_name(context, salt_principal, &salt_princ); if (ret != 0) { return ret; } ret = smb_krb5_get_pw_salt(context, salt_princ, &salt); krb5_free_principal(context, salt_princ); if (ret != 0) { return ret; } *_salt_data = talloc_strndup(mem_ctx, (char *)salt.data, salt.length); smb_krb5_free_data_contents(context, &salt); if (*_salt_data == NULL) { return ENOMEM; } return 0; } #if defined(HAVE_KRB5_GET_PERMITTED_ENCTYPES) /** * @brief Get a list of encryption types allowed for session keys * * @param[in] context The library context * * @param[in] enctypes An allocated, zero-terminated list of encryption types * * This function returns an allocated list of encryption types allowed for * session keys. * * Use free() to free the enctypes when it is no longer needed. * * @retval 0 Success; otherwise - Kerberos error codes */ krb5_error_code smb_krb5_get_allowed_etypes(krb5_context context, krb5_enctype **enctypes) { return krb5_get_permitted_enctypes(context, enctypes); } #elif defined(HAVE_KRB5_GET_DEFAULT_IN_TKT_ETYPES) krb5_error_code smb_krb5_get_allowed_etypes(krb5_context context, krb5_enctype **enctypes) { #ifdef HAVE_KRB5_PDU_NONE_DECL return krb5_get_default_in_tkt_etypes(context, KRB5_PDU_NONE, enctypes); #else return krb5_get_default_in_tkt_etypes(context, enctypes); #endif } #else #error UNKNOWN_GET_ENCTYPES_FUNCTIONS #endif /** * @brief Convert a string principal name to a Kerberos principal. * * @param[in] context The library context * * @param[in] name The principal as a unix charset string. * * @param[out] principal The newly allocated principal. * * Use krb5_free_principal() to free a principal when it is no longer needed. * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_parse_name(krb5_context context, const char *name, krb5_principal *principal) { krb5_error_code ret; char *utf8_name; size_t converted_size; TALLOC_CTX *frame = talloc_stackframe(); if (!push_utf8_talloc(frame, &utf8_name, name, &converted_size)) { talloc_free(frame); return ENOMEM; } ret = krb5_parse_name(context, utf8_name, principal); TALLOC_FREE(frame); return ret; } /** * @brief Convert a Kerberos principal structure to a string representation. * * The resulting string representation will be a unix charset name and is * talloc'ed. * * @param[in] mem_ctx The talloc context to allocate memory on. * * @param[in] context The library context. * * @param[in] principal The principal. * * @param[out] unix_name A string representation of the princpial name as with * unix charset. * * Use talloc_free() to free the string representation if it is no longer * needed. * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_unparse_name(TALLOC_CTX *mem_ctx, krb5_context context, krb5_const_principal principal, char **unix_name) { krb5_error_code ret; char *utf8_name; size_t converted_size; *unix_name = NULL; ret = krb5_unparse_name(context, principal, &utf8_name); if (ret) { return ret; } if (!pull_utf8_talloc(mem_ctx, unix_name, utf8_name, &converted_size)) { krb5_free_unparsed_name(context, utf8_name); return ENOMEM; } krb5_free_unparsed_name(context, utf8_name); return 0; } /** * @brief Free the contents of a krb5_data structure and zero the data field. * * @param[in] context The krb5 context * * @param[in] pdata The data structure to free contents of * * This function frees the contents, not the structure itself. */ void smb_krb5_free_data_contents(krb5_context context, krb5_data *pdata) { #if defined(HAVE_KRB5_FREE_DATA_CONTENTS) if (pdata->data) { krb5_free_data_contents(context, pdata); } #elif defined(HAVE_KRB5_DATA_FREE) krb5_data_free(context, pdata); #else SAFE_FREE(pdata->data); #endif } /* * @brief copy a buffer into a krb5_data struct * * @param[in] p The krb5_data * @param[in] data The data to copy * @param[in] length The length of the data to copy * @return krb5_error_code * * Caller has to free krb5_data with smb_krb5_free_data_contents(). */ krb5_error_code smb_krb5_copy_data_contents(krb5_data *p, const void *data, size_t len) { #if defined(HAVE_KRB5_DATA_COPY) return krb5_data_copy(p, data, len); #else if (len) { p->data = malloc(len); if (p->data == NULL) { return ENOMEM; } memmove(p->data, data, len); } else { p->data = NULL; } p->length = len; p->magic = KV5M_DATA; return 0; #endif } bool smb_krb5_get_smb_session_key(TALLOC_CTX *mem_ctx, krb5_context context, krb5_auth_context auth_context, DATA_BLOB *session_key, bool remote) { krb5_keyblock *skey = NULL; krb5_error_code err = 0; bool ret = false; if (remote) { #ifdef HAVE_KRB5_AUTH_CON_GETRECVSUBKEY err = krb5_auth_con_getrecvsubkey(context, auth_context, &skey); #else /* HAVE_KRB5_AUTH_CON_GETRECVSUBKEY */ err = krb5_auth_con_getremotesubkey(context, auth_context, &skey); #endif /* HAVE_KRB5_AUTH_CON_GETRECVSUBKEY */ } else { #ifdef HAVE_KRB5_AUTH_CON_GETSENDSUBKEY err = krb5_auth_con_getsendsubkey(context, auth_context, &skey); #else /* HAVE_KRB5_AUTH_CON_GETSENDSUBKEY */ err = krb5_auth_con_getlocalsubkey(context, auth_context, &skey); #endif /* HAVE_KRB5_AUTH_CON_GETSENDSUBKEY */ } if (err || skey == NULL) { DEBUG(10, ("KRB5 error getting session key %d\n", err)); goto done; } DEBUG(10, ("Got KRB5 session key of length %d\n", (int)KRB5_KEY_LENGTH(skey))); *session_key = data_blob_talloc(mem_ctx, KRB5_KEY_DATA(skey), KRB5_KEY_LENGTH(skey)); dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length); ret = true; done: if (skey) { krb5_free_keyblock(context, skey); } return ret; } /** * @brief Get talloced string component of a principal * * @param[in] mem_ctx The TALLOC_CTX * @param[in] context The krb5_context * @param[in] principal The principal * @param[in] component The component * @return string component * * Caller must talloc_free if the return value is not NULL. * */ char *smb_krb5_principal_get_comp_string(TALLOC_CTX *mem_ctx, krb5_context context, krb5_const_principal principal, unsigned int component) { #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING) return talloc_strdup(mem_ctx, krb5_principal_get_comp_string(context, principal, component)); #else krb5_data *data; if (component >= krb5_princ_size(context, principal)) { return NULL; } data = krb5_princ_component(context, principal, component); if (data == NULL) { return NULL; } return talloc_strndup(mem_ctx, data->data, data->length); #endif } /** * @brief * * @param[in] ccache_string A string pointing to the cache to renew the ticket * (e.g. FILE:/tmp/krb5cc_0) or NULL. If the principal * ccache has not been specified, the default ccache * will be used. * * @param[in] client_string The client principal string (e.g. user@SAMBA.SITE) * or NULL. If the principal string has not been * specified, the principal from the ccache will be * retrieved. * * @param[in] service_string The service ticket string * (e.g. krbtgt/SAMBA.SITE@SAMBA.SITE) or NULL. If * the sevice ticket is specified, it is parsed ( * with the realm part ignored) and used as the * server principal of the credential. Otherwise * the ticket-granting service is used. * * @param[in] expire_time A pointer to store the credentials end time or * NULL. * * @return 0 on Succes, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_renew_ticket(const char *ccache_string, const char *client_string, const char *service_string, time_t *expire_time) { krb5_error_code ret; krb5_context context = NULL; krb5_ccache ccache = NULL; krb5_principal client = NULL; krb5_creds creds, creds_in; ZERO_STRUCT(creds); ZERO_STRUCT(creds_in); initialize_krb5_error_table(); ret = krb5_init_context(&context); if (ret) { goto done; } if (!ccache_string) { ccache_string = krb5_cc_default_name(context); } if (!ccache_string) { ret = EINVAL; goto done; } DEBUG(10,("smb_krb5_renew_ticket: using %s as ccache\n", ccache_string)); /* FIXME: we should not fall back to defaults */ ret = krb5_cc_resolve(context, discard_const_p(char, ccache_string), &ccache); if (ret) { goto done; } if (client_string) { ret = smb_krb5_parse_name(context, client_string, &client); if (ret) { goto done; } } else { ret = krb5_cc_get_principal(context, ccache, &client); if (ret) { goto done; } } ret = krb5_get_renewed_creds(context, &creds, client, ccache, discard_const_p(char, service_string)); if (ret) { DEBUG(10,("smb_krb5_renew_ticket: krb5_get_kdc_cred failed: %s\n", error_message(ret))); goto done; } /* hm, doesn't that create a new one if the old one wasn't there? - Guenther */ ret = krb5_cc_initialize(context, ccache, client); if (ret) { goto done; } ret = krb5_cc_store_cred(context, ccache, &creds); if (expire_time) { *expire_time = (time_t) creds.times.endtime; } done: krb5_free_cred_contents(context, &creds_in); krb5_free_cred_contents(context, &creds); if (client) { krb5_free_principal(context, client); } if (ccache) { krb5_cc_close(context, ccache); } if (context) { krb5_free_context(context); } return ret; } /** * @brief Free the data stored in an smb_krb5_addresses structure. * * @param[in] context The library context * * @param[in] addr The address structure to free. * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_free_addresses(krb5_context context, smb_krb5_addresses *addr) { krb5_error_code ret = 0; if (addr == NULL) { return ret; } #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */ krb5_free_addresses(context, addr->addrs); #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */ ret = krb5_free_addresses(context, addr->addrs); SAFE_FREE(addr->addrs); #endif SAFE_FREE(addr); addr = NULL; return ret; } #define MAX_NETBIOSNAME_LEN 16 /** * @brief Add a netbios name to the array of addresses * * @param[in] kerb_addr A pointer to the smb_krb5_addresses to add the * netbios name to. * * @param[in] netbios_name The netbios name to add. * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_gen_netbios_krb5_address(smb_krb5_addresses **kerb_addr, const char *netbios_name) { krb5_error_code ret = 0; char buf[MAX_NETBIOSNAME_LEN]; int len; #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */ krb5_address **addrs = NULL; #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */ krb5_addresses *addrs = NULL; #endif *kerb_addr = (smb_krb5_addresses *)SMB_MALLOC(sizeof(smb_krb5_addresses)); if (*kerb_addr == NULL) { return ENOMEM; } /* temporarily duplicate put_name() code here to avoid dependency * issues for a 5 lines function */ len = strlen(netbios_name); memcpy(buf, netbios_name, (len < MAX_NETBIOSNAME_LEN) ? len : MAX_NETBIOSNAME_LEN - 1); if (len < MAX_NETBIOSNAME_LEN - 1) { memset(buf + len, ' ', MAX_NETBIOSNAME_LEN - 1 - len); } buf[MAX_NETBIOSNAME_LEN - 1] = 0x20; #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */ { int num_addr = 2; addrs = (krb5_address **)SMB_MALLOC(sizeof(krb5_address *) * num_addr); if (addrs == NULL) { SAFE_FREE(*kerb_addr); return ENOMEM; } memset(addrs, 0, sizeof(krb5_address *) * num_addr); addrs[0] = (krb5_address *)SMB_MALLOC(sizeof(krb5_address)); if (addrs[0] == NULL) { SAFE_FREE(addrs); SAFE_FREE(*kerb_addr); return ENOMEM; } addrs[0]->magic = KV5M_ADDRESS; addrs[0]->addrtype = KRB5_ADDR_NETBIOS; addrs[0]->length = MAX_NETBIOSNAME_LEN; addrs[0]->contents = (unsigned char *)SMB_MALLOC(addrs[0]->length); if (addrs[0]->contents == NULL) { SAFE_FREE(addrs[0]); SAFE_FREE(addrs); SAFE_FREE(*kerb_addr); return ENOMEM; } memcpy(addrs[0]->contents, buf, addrs[0]->length); addrs[1] = NULL; } #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */ { addrs = (krb5_addresses *)SMB_MALLOC(sizeof(krb5_addresses)); if (addrs == NULL) { SAFE_FREE(*kerb_addr); return ENOMEM; } memset(addrs, 0, sizeof(krb5_addresses)); addrs->len = 1; addrs->val = (krb5_address *)SMB_MALLOC(sizeof(krb5_address)); if (addrs->val == NULL) { SAFE_FREE(addrs); SAFE_FREE(kerb_addr); return ENOMEM; } addrs->val[0].addr_type = KRB5_ADDR_NETBIOS; addrs->val[0].address.length = MAX_NETBIOSNAME_LEN; addrs->val[0].address.data = (unsigned char *)SMB_MALLOC(addrs->val[0].address.length); if (addrs->val[0].address.data == NULL) { SAFE_FREE(addrs->val); SAFE_FREE(addrs); SAFE_FREE(*kerb_addr); return ENOMEM; } memcpy(addrs->val[0].address.data, buf, addrs->val[0].address.length); } #else #error UNKNOWN_KRB5_ADDRESS_FORMAT #endif (*kerb_addr)->addrs = addrs; return ret; } /** * @brief Get the enctype from a key table entry * * @param[in] kt_entry Key table entry to get the enctype from. * * @return The enctype from the entry. */ krb5_enctype smb_krb5_kt_get_enctype_from_entry(krb5_keytab_entry *kt_entry) { return KRB5_KEY_TYPE(KRB5_KT_KEY(kt_entry)); } /** * @brief Free the contents of a key table entry. * * @param[in] context The library context. * * @param[in] kt_entry The key table entry to free the contents of. * * @return 0 on success, a Kerberos error code otherwise. * * The pointer itself is not freed. */ krb5_error_code smb_krb5_kt_free_entry(krb5_context context, krb5_keytab_entry *kt_entry) { /* Try krb5_free_keytab_entry_contents first, since * MIT Kerberos >= 1.7 has both krb5_free_keytab_entry_contents and * krb5_kt_free_entry but only has a prototype for the first, while the * second is considered private. */ #if defined(HAVE_KRB5_FREE_KEYTAB_ENTRY_CONTENTS) return krb5_free_keytab_entry_contents(context, kt_entry); #elif defined(HAVE_KRB5_KT_FREE_ENTRY) return krb5_kt_free_entry(context, kt_entry); #else #error UNKNOWN_KT_FREE_FUNCTION #endif } /** * @brief Convert an encryption type to a string. * * @param[in] context The library context. * * @param[in] enctype The encryption type. * * @param[in] etype_s A pointer to store the allocated encryption type as a * string. * * @return 0 on success, a Kerberos error code otherwise. * * The caller needs to free the allocated string etype_s. */ krb5_error_code smb_krb5_enctype_to_string(krb5_context context, krb5_enctype enctype, char **etype_s) { #ifdef HAVE_KRB5_ENCTYPE_TO_STRING_WITH_KRB5_CONTEXT_ARG return krb5_enctype_to_string(context, enctype, etype_s); /* Heimdal */ #elif defined(HAVE_KRB5_ENCTYPE_TO_STRING_WITH_SIZE_T_ARG) char buf[256]; krb5_error_code ret = krb5_enctype_to_string(enctype, buf, 256); /* MIT */ if (ret) { return ret; } *etype_s = SMB_STRDUP(buf); if (!*etype_s) { return ENOMEM; } return ret; #else #error UNKNOWN_KRB5_ENCTYPE_TO_STRING_FUNCTION #endif } /* This MAX_NAME_LEN is a constant defined in krb5.h */ #ifndef MAX_KEYTAB_NAME_LEN #define MAX_KEYTAB_NAME_LEN 1100 #endif /** * @brief Open a key table readonly or with readwrite access. * * Allows to use a different keytab than the default one using a relative * path to the keytab. * * @param[in] context The library context * * @param[in] keytab_name_req The path to the key table. * * @param[in] write_access Open with readwrite access. * * @param[in] keytab A pointer o the opended key table. * * The keytab pointer should be freed using krb5_kt_close(). * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_kt_open_relative(krb5_context context, const char *keytab_name_req, bool write_access, krb5_keytab *keytab) { krb5_error_code ret = 0; TALLOC_CTX *mem_ctx; char keytab_string[MAX_KEYTAB_NAME_LEN]; char *kt_str = NULL; bool found_valid_name = false; const char *pragma = "FILE"; const char *tmp = NULL; if (!write_access && !keytab_name_req) { /* caller just wants to read the default keytab readonly, so be it */ return krb5_kt_default(context, keytab); } mem_ctx = talloc_init("smb_krb5_open_keytab"); if (!mem_ctx) { return ENOMEM; } #ifdef HAVE_WRFILE_KEYTAB if (write_access) { pragma = "WRFILE"; } #endif if (keytab_name_req) { if (strlen(keytab_name_req) > MAX_KEYTAB_NAME_LEN) { ret = KRB5_CONFIG_NOTENUFSPACE; goto out; } if ((strncmp(keytab_name_req, "WRFILE:", 7) == 0) || (strncmp(keytab_name_req, "FILE:", 5) == 0)) { tmp = keytab_name_req; goto resolve; } tmp = talloc_asprintf(mem_ctx, "%s:%s", pragma, keytab_name_req); if (!tmp) { ret = ENOMEM; goto out; } goto resolve; } /* we need to handle more complex keytab_strings, like: * "ANY:FILE:/etc/krb5.keytab,krb4:/etc/srvtab" */ ret = krb5_kt_default_name(context, &keytab_string[0], MAX_KEYTAB_NAME_LEN - 2); if (ret) { goto out; } DEBUG(10,("smb_krb5_open_keytab: krb5_kt_default_name returned %s\n", keytab_string)); tmp = talloc_strdup(mem_ctx, keytab_string); if (!tmp) { ret = ENOMEM; goto out; } if (strncmp(tmp, "ANY:", 4) == 0) { tmp += 4; } memset(&keytab_string, '\0', sizeof(keytab_string)); while (next_token_talloc(mem_ctx, &tmp, &kt_str, ",")) { if (strncmp(kt_str, "WRFILE:", 7) == 0) { found_valid_name = true; tmp = kt_str; tmp += 7; } if (strncmp(kt_str, "FILE:", 5) == 0) { found_valid_name = true; tmp = kt_str; tmp += 5; } if (tmp[0] == '/') { /* Treat as a FILE: keytab definition. */ found_valid_name = true; } if (found_valid_name) { if (tmp[0] != '/') { ret = KRB5_KT_BADNAME; goto out; } tmp = talloc_asprintf(mem_ctx, "%s:%s", pragma, tmp); if (!tmp) { ret = ENOMEM; goto out; } break; } } if (!found_valid_name) { ret = KRB5_KT_UNKNOWN_TYPE; goto out; } resolve: DEBUG(10,("smb_krb5_open_keytab: resolving: %s\n", tmp)); ret = krb5_kt_resolve(context, tmp, keytab); out: TALLOC_FREE(mem_ctx); return ret; } /** * @brief Open a key table readonly or with readwrite access. * * Allows to use a different keytab than the default one. The path needs to be * an absolute path or an error will be returned. * * @param[in] context The library context * * @param[in] keytab_name_req The path to the key table. * * @param[in] write_access Open with readwrite access. * * @param[in] keytab A pointer o the opended key table. * * The keytab pointer should be freed using krb5_kt_close(). * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_kt_open(krb5_context context, const char *keytab_name_req, bool write_access, krb5_keytab *keytab) { int cmp; if (keytab_name_req == NULL) { return KRB5_KT_BADNAME; } if (keytab_name_req[0] == '/') { goto open_keytab; } cmp = strncmp(keytab_name_req, "FILE:/", 6); if (cmp == 0) { goto open_keytab; } cmp = strncmp(keytab_name_req, "WRFILE:/", 8); if (cmp == 0) { goto open_keytab; } DBG_WARNING("ERROR: Invalid keytab name: %s\n", keytab_name_req); return KRB5_KT_BADNAME; open_keytab: return smb_krb5_kt_open_relative(context, keytab_name_req, write_access, keytab); } /** * @brief Get a key table name. * * @param[in] mem_ctx The talloc context to use for allocation. * * @param[in] context The library context. * * @param[in] keytab The key table to get the name from. * * @param[in] keytab_name A talloc'ed string of the key table name. * * The talloc'ed name string needs to be freed with talloc_free(). * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_kt_get_name(TALLOC_CTX *mem_ctx, krb5_context context, krb5_keytab keytab, const char **keytab_name) { char keytab_string[MAX_KEYTAB_NAME_LEN]; krb5_error_code ret = 0; ret = krb5_kt_get_name(context, keytab, keytab_string, MAX_KEYTAB_NAME_LEN - 2); if (ret) { return ret; } *keytab_name = talloc_strdup(mem_ctx, keytab_string); if (!*keytab_name) { return ENOMEM; } return ret; } /** * @brief Seek and delete old entries in a keytab based on the passed * principal. * * @param[in] context The KRB5 context to use. * * @param[in] keytab The keytab to operate on. * * @param[in] kvno The kvnco to use. * * @param[in] princ_s The principal as a string to search for. * * @param[in] princ The principal as a krb5_principal to search for. * * @param[in] flush Weather to flush the complete keytab. * * @param[in] keep_old_entries Keep the entry with the previous kvno. * * @retval 0 on Sucess * * @return An appropriate KRB5 error code. */ krb5_error_code smb_krb5_kt_seek_and_delete_old_entries(krb5_context context, krb5_keytab keytab, krb5_kvno kvno, krb5_enctype enctype, const char *princ_s, krb5_principal princ, bool flush, bool keep_old_entries) { krb5_error_code ret; krb5_kt_cursor cursor; krb5_keytab_entry kt_entry; char *ktprinc = NULL; krb5_kvno old_kvno = kvno - 1; TALLOC_CTX *tmp_ctx; ZERO_STRUCT(cursor); ZERO_STRUCT(kt_entry); ret = krb5_kt_start_seq_get(context, keytab, &cursor); if (ret == KRB5_KT_END || ret == ENOENT ) { /* no entries */ return 0; } tmp_ctx = talloc_new(NULL); if (tmp_ctx == NULL) { return ENOMEM; } DEBUG(3, (__location__ ": Will try to delete old keytab entries\n")); while (!krb5_kt_next_entry(context, keytab, &kt_entry, &cursor)) { bool name_ok = false; krb5_enctype kt_entry_enctype = smb_krb5_kt_get_enctype_from_entry(&kt_entry); if (!flush && (princ_s != NULL)) { ret = smb_krb5_unparse_name(tmp_ctx, context, kt_entry.principal, &ktprinc); if (ret) { DEBUG(1, (__location__ ": smb_krb5_unparse_name failed " "(%s)\n", error_message(ret))); goto out; } #ifdef HAVE_KRB5_KT_COMPARE name_ok = krb5_kt_compare(context, &kt_entry, princ, 0, 0); #else name_ok = (strcmp(ktprinc, princ_s) == 0); #endif if (!name_ok) { DEBUG(10, (__location__ ": ignoring keytab " "entry principal %s, kvno = %d\n", ktprinc, kt_entry.vno)); /* Not a match, * just free this entry and continue. */ ret = smb_krb5_kt_free_entry(context, &kt_entry); ZERO_STRUCT(kt_entry); if (ret) { DEBUG(1, (__location__ ": smb_krb5_kt_free_entry " "failed (%s)\n", error_message(ret))); goto out; } TALLOC_FREE(ktprinc); continue; } TALLOC_FREE(ktprinc); } /*------------------------------------------------------------ * Save the entries with kvno - 1. This is what microsoft does * to allow people with existing sessions that have kvno - 1 * to still work. Otherwise, when the password for the machine * changes, all kerberizied sessions will 'break' until either * the client reboots or the client's session key expires and * they get a new session ticket with the new kvno. * Some keytab files only store the kvno in 8bits, limit * the compare accordingly. */ if (!flush && ((kt_entry.vno & 0xff) == (old_kvno & 0xff))) { DEBUG(5, (__location__ ": Saving previous (kvno %d) " "entry for principal: %s.\n", old_kvno, princ_s)); continue; } if (keep_old_entries) { DEBUG(5, (__location__ ": Saving old (kvno %d) " "entry for principal: %s.\n", kvno, princ_s)); continue; } if (!flush && ((kt_entry.vno & 0xff) == (kvno & 0xff)) && (kt_entry_enctype != enctype)) { DEBUG(5, (__location__ ": Saving entry with kvno [%d] " "enctype [%d] for principal: %s.\n", kvno, kt_entry_enctype, princ_s)); continue; } DEBUG(5, (__location__ ": Found old entry for principal: %s " "(kvno %d) - trying to remove it.\n", princ_s, kt_entry.vno)); ret = krb5_kt_end_seq_get(context, keytab, &cursor); ZERO_STRUCT(cursor); if (ret) { DEBUG(1, (__location__ ": krb5_kt_end_seq_get() " "failed (%s)\n", error_message(ret))); goto out; } ret = krb5_kt_remove_entry(context, keytab, &kt_entry); if (ret) { DEBUG(1, (__location__ ": krb5_kt_remove_entry() " "failed (%s)\n", error_message(ret))); goto out; } DEBUG(5, (__location__ ": removed old entry for principal: " "%s (kvno %d).\n", princ_s, kt_entry.vno)); ret = krb5_kt_start_seq_get(context, keytab, &cursor); if (ret) { DEBUG(1, (__location__ ": krb5_kt_start_seq() failed " "(%s)\n", error_message(ret))); goto out; } ret = smb_krb5_kt_free_entry(context, &kt_entry); ZERO_STRUCT(kt_entry); if (ret) { DEBUG(1, (__location__ ": krb5_kt_remove_entry() " "failed (%s)\n", error_message(ret))); goto out; } } out: talloc_free(tmp_ctx); if (!all_zero((uint8_t *)&kt_entry, sizeof(kt_entry))) { smb_krb5_kt_free_entry(context, &kt_entry); } if (!all_zero((uint8_t *)&cursor, sizeof(cursor))) { krb5_kt_end_seq_get(context, keytab, &cursor); } return ret; } /** * @brief Add a keytab entry for the given principal * * @param[in] context The krb5 context to use. * * @param[in] keytab The keytab to add the entry to. * * @param[in] kvno The kvno to use. * * @param[in] princ_s The principal as a string. * * @param[in] salt_principal The salt principal to salt the password with. * Only needed for keys which support salting. * If no salt is used set no_salt to false and * pass NULL here. * * @param[in] enctype The encryption type of the keytab entry. * * @param[in] password The password of the keytab entry. * * @param[in] no_salt If the password should not be salted. Normally * this is only set to false for encryption types * which do not support salting like RC4. * * @param[in] keep_old_entries Wether to keep or delte old keytab entries. * * @retval 0 on Success * * @return A corresponding KRB5 error code. * * @see smb_krb5_kt_open() */ krb5_error_code smb_krb5_kt_add_entry(krb5_context context, krb5_keytab keytab, krb5_kvno kvno, const char *princ_s, const char *salt_principal, krb5_enctype enctype, krb5_data *password, bool no_salt, bool keep_old_entries) { krb5_error_code ret; krb5_keytab_entry kt_entry; krb5_principal princ = NULL; krb5_keyblock *keyp; ZERO_STRUCT(kt_entry); ret = smb_krb5_parse_name(context, princ_s, &princ); if (ret) { DEBUG(1, (__location__ ": smb_krb5_parse_name(%s) " "failed (%s)\n", princ_s, error_message(ret))); goto out; } /* Seek and delete old keytab entries */ ret = smb_krb5_kt_seek_and_delete_old_entries(context, keytab, kvno, enctype, princ_s, princ, false, keep_old_entries); if (ret) { goto out; } /* If we get here, we have deleted all the old entries with kvno's * not equal to the current kvno-1. */ keyp = KRB5_KT_KEY(&kt_entry); if (no_salt) { KRB5_KEY_DATA(keyp) = (KRB5_KEY_DATA_CAST *)SMB_MALLOC(password->length); if (KRB5_KEY_DATA(keyp) == NULL) { ret = ENOMEM; goto out; } memcpy(KRB5_KEY_DATA(keyp), password->data, password->length); KRB5_KEY_LENGTH(keyp) = password->length; KRB5_KEY_TYPE(keyp) = enctype; } else { krb5_principal salt_princ = NULL; /* Now add keytab entries for all encryption types */ ret = smb_krb5_parse_name(context, salt_principal, &salt_princ); if (ret) { DBG_WARNING("krb5_parse_name(%s) failed (%s)\n", salt_principal, error_message(ret)); goto out; } ret = smb_krb5_create_key_from_string(context, salt_princ, NULL, password, enctype, keyp); krb5_free_principal(context, salt_princ); if (ret != 0) { goto out; } } kt_entry.principal = princ; kt_entry.vno = kvno; DEBUG(3, (__location__ ": adding keytab entry for (%s) with " "encryption type (%d) and version (%d)\n", princ_s, enctype, kt_entry.vno)); ret = krb5_kt_add_entry(context, keytab, &kt_entry); krb5_free_keyblock_contents(context, keyp); ZERO_STRUCT(kt_entry); if (ret) { DEBUG(1, (__location__ ": adding entry to keytab " "failed (%s)\n", error_message(ret))); goto out; } out: if (princ) { krb5_free_principal(context, princ); } return ret; } #if defined(HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE) && \ defined(HAVE_KRB5_GET_CREDS_OPT_ALLOC) && \ defined(HAVE_KRB5_GET_CREDS) static krb5_error_code smb_krb5_get_credentials_for_user_opt(krb5_context context, krb5_ccache ccache, krb5_principal me, krb5_principal server, krb5_principal impersonate_princ, krb5_creds **out_creds) { krb5_error_code ret; krb5_get_creds_opt opt; ret = krb5_get_creds_opt_alloc(context, &opt); if (ret) { goto done; } krb5_get_creds_opt_add_options(context, opt, KRB5_GC_FORWARDABLE); if (impersonate_princ) { ret = krb5_get_creds_opt_set_impersonate(context, opt, impersonate_princ); if (ret) { goto done; } } ret = krb5_get_creds(context, opt, ccache, server, out_creds); if (ret) { goto done; } done: if (opt) { krb5_get_creds_opt_free(context, opt); } return ret; } #endif /* HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE */ #ifdef HAVE_KRB5_GET_CREDENTIALS_FOR_USER #if !HAVE_DECL_KRB5_GET_CREDENTIALS_FOR_USER krb5_error_code KRB5_CALLCONV krb5_get_credentials_for_user(krb5_context context, krb5_flags options, krb5_ccache ccache, krb5_creds *in_creds, krb5_data *subject_cert, krb5_creds **out_creds); #endif /* !HAVE_DECL_KRB5_GET_CREDENTIALS_FOR_USER */ static krb5_error_code smb_krb5_get_credentials_for_user(krb5_context context, krb5_ccache ccache, krb5_principal me, krb5_principal server, krb5_principal impersonate_princ, krb5_creds **out_creds) { krb5_error_code ret; krb5_creds in_creds; ZERO_STRUCT(in_creds); if (impersonate_princ) { in_creds.server = me; in_creds.client = impersonate_princ; ret = krb5_get_credentials_for_user(context, 0, /* krb5_flags options */ ccache, &in_creds, NULL, /* krb5_data *subject_cert */ out_creds); } else { in_creds.client = me; in_creds.server = server; ret = krb5_get_credentials(context, 0, ccache, &in_creds, out_creds); } return ret; } #endif /* HAVE_KRB5_GET_CREDENTIALS_FOR_USER */ /* * smb_krb5_get_credentials * * @brief Get krb5 credentials for a server * * @param[in] context An initialized krb5_context * @param[in] ccache An initialized krb5_ccache * @param[in] me The krb5_principal of the caller * @param[in] server The krb5_principal of the requested service * @param[in] impersonate_princ The krb5_principal of a user to impersonate as (optional) * @param[out] out_creds The returned krb5_creds structure * @return krb5_error_code * */ krb5_error_code smb_krb5_get_credentials(krb5_context context, krb5_ccache ccache, krb5_principal me, krb5_principal server, krb5_principal impersonate_princ, krb5_creds **out_creds) { krb5_error_code ret; krb5_creds *creds = NULL; if (out_creds != NULL) { *out_creds = NULL; } if (impersonate_princ) { #ifdef HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE /* Heimdal */ ret = smb_krb5_get_credentials_for_user_opt(context, ccache, me, server, impersonate_princ, &creds); #elif defined(HAVE_KRB5_GET_CREDENTIALS_FOR_USER) /* MIT */ ret = smb_krb5_get_credentials_for_user(context, ccache, me, server, impersonate_princ, &creds); #else ret = ENOTSUP; #endif } else { krb5_creds in_creds; ZERO_STRUCT(in_creds); in_creds.client = me; in_creds.server = server; ret = krb5_get_credentials(context, 0, ccache, &in_creds, &creds); } if (ret) { goto done; } if (out_creds) { *out_creds = creds; } done: if (creds && ret) { krb5_free_creds(context, creds); } return ret; } /** * @brief Initialize a krb5_keyblock with the given data. * * Initialized a new keyblock, allocates the contents fo the key and * copies the data into the keyblock. * * @param[in] context The library context * * @param[in] enctype The encryption type. * * @param[in] data The date to initialize the keyblock with. * * @param[in] length The length of the keyblock. * * @param[in] key Newly allocated keyblock structure. * * The key date must be freed using krb5_free_keyblock_contents() when it is * no longer needed. * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_keyblock_init_contents(krb5_context context, krb5_enctype enctype, const void *data, size_t length, krb5_keyblock *key) { #if defined(HAVE_KRB5_KEYBLOCK_INIT) return krb5_keyblock_init(context, enctype, data, length, key); #else memset(key, 0, sizeof(krb5_keyblock)); KRB5_KEY_DATA(key) = SMB_MALLOC(length); if (NULL == KRB5_KEY_DATA(key)) { return ENOMEM; } memcpy(KRB5_KEY_DATA(key), data, length); KRB5_KEY_LENGTH(key) = length; KRB5_KEY_TYPE(key) = enctype; return 0; #endif } /** * @brief Simulate a kinit by putting the tgt in the given credential cache. * * This function uses a keyblock rather than needingthe original password. * * @param[in] ctx The library context * * @param[in] cc The credential cache to put the tgt in. * * @param[in] principal The client princial * * @param[in] keyblock The keyblock to use. * * @param[in] target_service The service name of the initial credentials (or NULL). * * @param[in] krb_options Initial credential options. * * @param[in] expire_time A pointer to store the experation time of the * credentials (or NULL). * * @param[in] kdc_time A pointer to store the time when the ticket becomes * valid (or NULL). * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_kinit_keyblock_ccache(krb5_context ctx, krb5_ccache cc, krb5_principal principal, krb5_keyblock *keyblock, const char *target_service, krb5_get_init_creds_opt *krb_options, time_t *expire_time, time_t *kdc_time) { krb5_error_code code = 0; krb5_creds my_creds; #if defined(HAVE_KRB5_GET_INIT_CREDS_KEYBLOCK) code = krb5_get_init_creds_keyblock(ctx, &my_creds, principal, keyblock, 0, target_service, krb_options); #elif defined(HAVE_KRB5_GET_INIT_CREDS_KEYTAB) { #define SMB_CREDS_KEYTAB "MEMORY:tmp_smb_creds_XXXXXX" char tmp_name[sizeof(SMB_CREDS_KEYTAB)]; krb5_keytab_entry entry; krb5_keytab keytab; mode_t mask; memset(&entry, 0, sizeof(entry)); entry.principal = principal; *(KRB5_KT_KEY(&entry)) = *keyblock; memcpy(tmp_name, SMB_CREDS_KEYTAB, sizeof(SMB_CREDS_KEYTAB)); mask = umask(S_IRWXO | S_IRWXG); mktemp(tmp_name); umask(mask); if (tmp_name[0] == 0) { return KRB5_KT_BADNAME; } code = krb5_kt_resolve(ctx, tmp_name, &keytab); if (code) { return code; } code = krb5_kt_add_entry(ctx, keytab, &entry); if (code) { (void)krb5_kt_close(ctx, keytab); goto done; } code = krb5_get_init_creds_keytab(ctx, &my_creds, principal, keytab, 0, target_service, krb_options); (void)krb5_kt_close(ctx, keytab); } #else #error krb5_get_init_creds_keyblock not available! #endif if (code) { return code; } #ifndef SAMBA4_USES_HEIMDAL /* MIT */ /* * We need to store the principal as returned from the KDC to the * credentials cache. If we don't do that the KRB5 library is not * able to find the tickets it is looking for */ principal = my_creds.client; #endif code = krb5_cc_initialize(ctx, cc, principal); if (code) { goto done; } code = krb5_cc_store_cred(ctx, cc, &my_creds); if (code) { goto done; } if (expire_time) { *expire_time = (time_t) my_creds.times.endtime; } if (kdc_time) { *kdc_time = (time_t) my_creds.times.starttime; } code = 0; done: krb5_free_cred_contents(ctx, &my_creds); return code; } /** * @brief Simulate a kinit by putting the tgt in the given credential cache. * * @param[in] ctx The library context * * @param[in] cc The credential cache to put the tgt in. * * @param[in] principal The client princial * * @param[in] password The password (or NULL). * * @param[in] target_service The service name of the initial credentials (or NULL). * * @param[in] krb_options Initial credential options. * * @param[in] expire_time A pointer to store the experation time of the * credentials (or NULL). * * @param[in] kdc_time A pointer to store the time when the ticket becomes * valid (or NULL). * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_kinit_password_ccache(krb5_context ctx, krb5_ccache cc, krb5_principal principal, const char *password, const char *target_service, krb5_get_init_creds_opt *krb_options, time_t *expire_time, time_t *kdc_time) { krb5_error_code code = 0; krb5_creds my_creds; code = krb5_get_init_creds_password(ctx, &my_creds, principal, password, NULL, NULL, 0, target_service, krb_options); if (code) { return code; } #ifndef SAMBA4_USES_HEIMDAL /* MIT */ /* * We need to store the principal as returned from the KDC to the * credentials cache. If we don't do that the KRB5 library is not * able to find the tickets it is looking for */ principal = my_creds.client; #endif code = krb5_cc_initialize(ctx, cc, principal); if (code) { goto done; } code = krb5_cc_store_cred(ctx, cc, &my_creds); if (code) { goto done; } if (expire_time) { *expire_time = (time_t) my_creds.times.endtime; } if (kdc_time) { *kdc_time = (time_t) my_creds.times.starttime; } code = 0; done: krb5_free_cred_contents(ctx, &my_creds); return code; } #ifdef SAMBA4_USES_HEIMDAL /** * @brief Simulate a kinit by putting the tgt in the given credential cache. * * @param[in] ctx The library context * * @param[in] cc The credential cache to store the tgt in. * * @param[in] principal The initial client princial. * * @param[in] password The password (or NULL). * * @param[in] impersonate_principal The impersonatiion principal (or NULL). * * @param[in] self_service The local service for S4U2Self if * impersonate_principal is specified). * * @param[in] target_service The service name of the initial credentials * (kpasswd/REALM or a remote service). It defaults * to the krbtgt if NULL. * * @param[in] krb_options Initial credential options. * * @param[in] expire_time A pointer to store the experation time of the * credentials (or NULL). * * @param[in] kdc_time A pointer to store the time when the ticket becomes * valid (or NULL). * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_kinit_s4u2_ccache(krb5_context ctx, krb5_ccache store_cc, krb5_principal init_principal, const char *init_password, krb5_principal impersonate_principal, const char *self_service, const char *target_service, krb5_get_init_creds_opt *krb_options, time_t *expire_time, time_t *kdc_time) { krb5_error_code code = 0; krb5_get_creds_opt options; krb5_principal store_principal; krb5_creds store_creds; krb5_creds *s4u2self_creds; Ticket s4u2self_ticket; size_t s4u2self_ticketlen; krb5_creds *s4u2proxy_creds; krb5_principal self_princ; bool s4u2proxy; krb5_principal target_princ; krb5_ccache tmp_cc; const char *self_realm; const char *client_realm = NULL; krb5_principal blacklist_principal = NULL; krb5_principal whitelist_principal = NULL; code = krb5_get_init_creds_password(ctx, &store_creds, init_principal, init_password, NULL, NULL, 0, NULL, krb_options); if (code != 0) { return code; } store_principal = init_principal; /* * We are trying S4U2Self now: * * As we do not want to expose our TGT in the * krb5_ccache, which is also holds the impersonated creds. * * Some low level krb5/gssapi function might use the TGT * identity and let the client act as our machine account. * * We need to avoid that and use a temporary krb5_ccache * in order to pass our TGT to the krb5_get_creds() function. */ code = krb5_cc_new_unique(ctx, NULL, NULL, &tmp_cc); if (code != 0) { krb5_free_cred_contents(ctx, &store_creds); return code; } code = krb5_cc_initialize(ctx, tmp_cc, store_creds.client); if (code != 0) { krb5_cc_destroy(ctx, tmp_cc); krb5_free_cred_contents(ctx, &store_creds); return code; } code = krb5_cc_store_cred(ctx, tmp_cc, &store_creds); if (code != 0) { krb5_free_cred_contents(ctx, &store_creds); krb5_cc_destroy(ctx, tmp_cc); return code; } /* * we need to remember the client principal of our * TGT and make sure the KDC does not return this * in the impersonated tickets. This can happen * if the KDC does not support S4U2Self and S4U2Proxy. */ blacklist_principal = store_creds.client; store_creds.client = NULL; krb5_free_cred_contents(ctx, &store_creds); /* * Check if we also need S4U2Proxy or if S4U2Self is * enough in order to get a ticket for the target. */ if (target_service == NULL) { s4u2proxy = false; } else if (strcmp(target_service, self_service) == 0) { s4u2proxy = false; } else { s4u2proxy = true; } /* * For S4U2Self we need our own service principal, * which belongs to our own realm (available on * our client principal). */ self_realm = krb5_principal_get_realm(ctx, init_principal); code = krb5_parse_name(ctx, self_service, &self_princ); if (code != 0) { krb5_free_principal(ctx, blacklist_principal); krb5_cc_destroy(ctx, tmp_cc); return code; } code = krb5_principal_set_realm(ctx, self_princ, self_realm); if (code != 0) { krb5_free_principal(ctx, blacklist_principal); krb5_free_principal(ctx, self_princ); krb5_cc_destroy(ctx, tmp_cc); return code; } code = krb5_get_creds_opt_alloc(ctx, &options); if (code != 0) { krb5_free_principal(ctx, blacklist_principal); krb5_free_principal(ctx, self_princ); krb5_cc_destroy(ctx, tmp_cc); return code; } if (s4u2proxy) { /* * If we want S4U2Proxy, we need the forwardable flag * on the S4U2Self ticket. */ krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_FORWARDABLE); } code = krb5_get_creds_opt_set_impersonate(ctx, options, impersonate_principal); if (code != 0) { krb5_get_creds_opt_free(ctx, options); krb5_free_principal(ctx, blacklist_principal); krb5_free_principal(ctx, self_princ); krb5_cc_destroy(ctx, tmp_cc); return code; } code = krb5_get_creds(ctx, options, tmp_cc, self_princ, &s4u2self_creds); krb5_get_creds_opt_free(ctx, options); krb5_free_principal(ctx, self_princ); if (code != 0) { krb5_free_principal(ctx, blacklist_principal); krb5_cc_destroy(ctx, tmp_cc); return code; } if (!s4u2proxy) { krb5_cc_destroy(ctx, tmp_cc); /* * Now make sure we store the impersonated principal * and creds instead of the TGT related stuff * in the krb5_ccache of the caller. */ code = krb5_copy_creds_contents(ctx, s4u2self_creds, &store_creds); krb5_free_creds(ctx, s4u2self_creds); if (code != 0) { return code; } /* * It's important to store the principal the KDC * returned, as otherwise the caller would not find * the S4U2Self ticket in the krb5_ccache lookup. */ store_principal = store_creds.client; goto store; } /* * We are trying S4U2Proxy: * * We need the ticket from the S4U2Self step * and our TGT in order to get the delegated ticket. */ code = decode_Ticket((const uint8_t *)s4u2self_creds->ticket.data, s4u2self_creds->ticket.length, &s4u2self_ticket, &s4u2self_ticketlen); if (code != 0) { krb5_free_creds(ctx, s4u2self_creds); krb5_free_principal(ctx, blacklist_principal); krb5_cc_destroy(ctx, tmp_cc); return code; } /* * we need to remember the client principal of the * S4U2Self stage and as it needs to match the one we * will get for the S4U2Proxy stage. We need this * in order to detect KDCs which does not support S4U2Proxy. */ whitelist_principal = s4u2self_creds->client; s4u2self_creds->client = NULL; krb5_free_creds(ctx, s4u2self_creds); /* * For S4U2Proxy we also got a target service principal, * which also belongs to our own realm (available on * our client principal). */ code = krb5_parse_name(ctx, target_service, &target_princ); if (code != 0) { free_Ticket(&s4u2self_ticket); krb5_free_principal(ctx, whitelist_principal); krb5_free_principal(ctx, blacklist_principal); krb5_cc_destroy(ctx, tmp_cc); return code; } code = krb5_principal_set_realm(ctx, target_princ, self_realm); if (code != 0) { free_Ticket(&s4u2self_ticket); krb5_free_principal(ctx, target_princ); krb5_free_principal(ctx, whitelist_principal); krb5_free_principal(ctx, blacklist_principal); krb5_cc_destroy(ctx, tmp_cc); return code; } code = krb5_get_creds_opt_alloc(ctx, &options); if (code != 0) { free_Ticket(&s4u2self_ticket); krb5_free_principal(ctx, target_princ); krb5_free_principal(ctx, whitelist_principal); krb5_free_principal(ctx, blacklist_principal); krb5_cc_destroy(ctx, tmp_cc); return code; } krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_FORWARDABLE); krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_CONSTRAINED_DELEGATION); code = krb5_get_creds_opt_set_ticket(ctx, options, &s4u2self_ticket); free_Ticket(&s4u2self_ticket); if (code != 0) { krb5_get_creds_opt_free(ctx, options); krb5_free_principal(ctx, target_princ); krb5_free_principal(ctx, whitelist_principal); krb5_free_principal(ctx, blacklist_principal); krb5_cc_destroy(ctx, tmp_cc); return code; } code = krb5_get_creds(ctx, options, tmp_cc, target_princ, &s4u2proxy_creds); krb5_get_creds_opt_free(ctx, options); krb5_free_principal(ctx, target_princ); krb5_cc_destroy(ctx, tmp_cc); if (code != 0) { krb5_free_principal(ctx, whitelist_principal); krb5_free_principal(ctx, blacklist_principal); return code; } /* * Now make sure we store the impersonated principal * and creds instead of the TGT related stuff * in the krb5_ccache of the caller. */ code = krb5_copy_creds_contents(ctx, s4u2proxy_creds, &store_creds); krb5_free_creds(ctx, s4u2proxy_creds); if (code != 0) { krb5_free_principal(ctx, whitelist_principal); krb5_free_principal(ctx, blacklist_principal); return code; } /* * It's important to store the principal the KDC * returned, as otherwise the caller would not find * the S4U2Self ticket in the krb5_ccache lookup. */ store_principal = store_creds.client; store: if (blacklist_principal && krb5_principal_compare(ctx, store_creds.client, blacklist_principal)) { char *sp = NULL; char *ip = NULL; code = krb5_unparse_name(ctx, blacklist_principal, &sp); if (code != 0) { sp = NULL; } code = krb5_unparse_name(ctx, impersonate_principal, &ip); if (code != 0) { ip = NULL; } DEBUG(1, ("smb_krb5_kinit_password_cache: " "KDC returned self principal[%s] while impersonating [%s]\n", sp?sp:"", ip?ip:"")); SAFE_FREE(sp); SAFE_FREE(ip); krb5_free_principal(ctx, whitelist_principal); krb5_free_principal(ctx, blacklist_principal); krb5_free_cred_contents(ctx, &store_creds); return KRB5_FWD_BAD_PRINCIPAL; } if (blacklist_principal) { krb5_free_principal(ctx, blacklist_principal); } if (whitelist_principal && !krb5_principal_compare(ctx, store_creds.client, whitelist_principal)) { char *sp = NULL; char *ep = NULL; code = krb5_unparse_name(ctx, store_creds.client, &sp); if (code != 0) { sp = NULL; } code = krb5_unparse_name(ctx, whitelist_principal, &ep); if (code != 0) { ep = NULL; } DEBUG(1, ("smb_krb5_kinit_password_cache: " "KDC returned wrong principal[%s] we expected [%s]\n", sp?sp:"", ep?ep:"")); SAFE_FREE(sp); SAFE_FREE(ep); krb5_free_principal(ctx, whitelist_principal); krb5_free_cred_contents(ctx, &store_creds); return KRB5_FWD_BAD_PRINCIPAL; } if (whitelist_principal) { krb5_free_principal(ctx, whitelist_principal); } code = krb5_cc_initialize(ctx, store_cc, store_principal); if (code != 0) { krb5_free_cred_contents(ctx, &store_creds); return code; } code = krb5_cc_store_cred(ctx, store_cc, &store_creds); if (code != 0) { krb5_free_cred_contents(ctx, &store_creds); return code; } client_realm = krb5_principal_get_realm(ctx, store_creds.client); if (client_realm != NULL) { /* * Because the CANON flag doesn't have any impact * on the impersonate_principal => store_creds.client * realm mapping. We need to store the credentials twice, * once with the returned realm and once with the * realm of impersonate_principal. */ code = krb5_principal_set_realm(ctx, store_creds.server, client_realm); if (code != 0) { krb5_free_cred_contents(ctx, &store_creds); return code; } code = krb5_cc_store_cred(ctx, store_cc, &store_creds); if (code != 0) { krb5_free_cred_contents(ctx, &store_creds); return code; } } if (expire_time) { *expire_time = (time_t) store_creds.times.endtime; } if (kdc_time) { *kdc_time = (time_t) store_creds.times.starttime; } krb5_free_cred_contents(ctx, &store_creds); return 0; } #endif #if !defined(HAVE_KRB5_MAKE_PRINCIPAL) && defined(HAVE_KRB5_BUILD_PRINCIPAL_ALLOC_VA) /** * @brief Create a principal name using a variable argument list. * * @param[in] context The library context. * * @param[inout] principal A pointer to the principal structure. * * @param[in] _realm The realm to use. If NULL then the function will * get the default realm name. * * @param[in] ... A list of 'char *' components, ending with NULL. * * Use krb5_free_principal() to free the principal when it is no longer needed. * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_make_principal(krb5_context context, krb5_principal *principal, const char *_realm, ...) { krb5_error_code code; bool free_realm; char *realm; va_list ap; if (_realm) { realm = discard_const_p(char, _realm); free_realm = false; } else { code = krb5_get_default_realm(context, &realm); if (code) { return code; } free_realm = true; } va_start(ap, _realm); code = krb5_build_principal_alloc_va(context, principal, strlen(realm), realm, ap); va_end(ap); if (free_realm) { krb5_free_default_realm(context, realm); } return code; } #endif #if !defined(HAVE_KRB5_CC_GET_LIFETIME) && defined(HAVE_KRB5_CC_RETRIEVE_CRED) /** * @brief Get the lifetime of the initial ticket in the cache. * * @param[in] context The kerberos context. * * @param[in] id The credential cache to get the ticket lifetime. * * @param[out] t A pointer to a time value to store the lifetime. * * @return 0 on success, a krb5_error_code on error. */ krb5_error_code smb_krb5_cc_get_lifetime(krb5_context context, krb5_ccache id, time_t *t) { krb5_cc_cursor cursor; krb5_error_code kerr; krb5_creds cred; krb5_timestamp now; *t = 0; kerr = krb5_timeofday(context, &now); if (kerr) { return kerr; } kerr = krb5_cc_start_seq_get(context, id, &cursor); if (kerr) { return kerr; } while ((kerr = krb5_cc_next_cred(context, id, &cursor, &cred)) == 0) { #ifndef HAVE_FLAGS_IN_KRB5_CREDS if (cred.ticket_flags & TKT_FLG_INITIAL) { #else if (cred.flags.b.initial) { #endif if (now < cred.times.endtime) { *t = (time_t) (cred.times.endtime - now); } krb5_free_cred_contents(context, &cred); break; } krb5_free_cred_contents(context, &cred); } krb5_cc_end_seq_get(context, id, &cursor); return kerr; } #endif /* HAVE_KRB5_CC_GET_LIFETIME */ #if !defined(HAVE_KRB5_FREE_CHECKSUM_CONTENTS) && defined(HAVE_FREE_CHECKSUM) void smb_krb5_free_checksum_contents(krb5_context ctx, krb5_checksum *cksum) { free_Checksum(cksum); } #endif /** * @brief Compute a checksum operating on a keyblock. * * This function computes a checksum over a PAC using the keyblock for a keyed * checksum. * * @param[in] mem_ctx A talloc context to alocate the signature on. * * @param[in] pac_data The PAC as input. * * @param[in] context The library context. * * @param[in] keyblock Encryption key for a keyed checksum. * * @param[out] sig_type The checksum type * * @param[out] sig_blob The talloc'ed checksum * * The caller must free the sig_blob with talloc_free() when it is not needed * anymore. * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_make_pac_checksum(TALLOC_CTX *mem_ctx, DATA_BLOB *pac_data, krb5_context context, const krb5_keyblock *keyblock, uint32_t *sig_type, DATA_BLOB *sig_blob) { krb5_error_code ret; krb5_checksum cksum; #if defined(HAVE_KRB5_CRYPTO_INIT) && defined(HAVE_KRB5_CREATE_CHECKSUM) krb5_crypto crypto; ret = krb5_crypto_init(context, keyblock, 0, &crypto); if (ret) { DEBUG(0,("krb5_crypto_init() failed: %s\n", smb_get_krb5_error_message(context, ret, mem_ctx))); return ret; } ret = krb5_create_checksum(context, crypto, KRB5_KU_OTHER_CKSUM, 0, pac_data->data, pac_data->length, &cksum); if (ret) { DEBUG(2, ("PAC Verification failed: %s\n", smb_get_krb5_error_message(context, ret, mem_ctx))); } krb5_crypto_destroy(context, crypto); if (ret) { return ret; } *sig_type = cksum.cksumtype; *sig_blob = data_blob_talloc(mem_ctx, cksum.checksum.data, cksum.checksum.length); #elif defined(HAVE_KRB5_C_MAKE_CHECKSUM) krb5_data input; input.data = (char *)pac_data->data; input.length = pac_data->length; ret = krb5_c_make_checksum(context, 0, keyblock, KRB5_KEYUSAGE_APP_DATA_CKSUM, &input, &cksum); if (ret) { DEBUG(2, ("PAC Verification failed: %s\n", smb_get_krb5_error_message(context, ret, mem_ctx))); return ret; } *sig_type = cksum.checksum_type; *sig_blob = data_blob_talloc(mem_ctx, cksum.contents, cksum.length); #else #error krb5_create_checksum or krb5_c_make_checksum not available #endif /* HAVE_KRB5_C_MAKE_CHECKSUM */ smb_krb5_free_checksum_contents(context, &cksum); return 0; } /** * @brief Get realm of a principal * * @param[in] context The library context * * @param[in] principal The principal to get the realm from. * * @return An allocated string with the realm or NULL if an error occurred. * * The caller must free the realm string with free() if not needed anymore. */ char *smb_krb5_principal_get_realm(krb5_context context, krb5_const_principal principal) { #ifdef HAVE_KRB5_PRINCIPAL_GET_REALM /* Heimdal */ return strdup(discard_const_p(char, krb5_principal_get_realm(context, principal))); #elif defined(krb5_princ_realm) /* MIT */ krb5_data *realm; realm = discard_const_p(krb5_data, krb5_princ_realm(context, principal)); return strndup(realm->data, realm->length); #else #error UNKNOWN_GET_PRINC_REALM_FUNCTIONS #endif } /** * @brief Get realm of a principal * * @param[in] context The library context * * @param[in] principal The principal to set the realm * * @param[in] realm The realm as a string to set. * * @retur 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_principal_set_realm(krb5_context context, krb5_principal principal, const char *realm) { #ifdef HAVE_KRB5_PRINCIPAL_SET_REALM /* Heimdal */ return krb5_principal_set_realm(context, principal, realm); #elif defined(krb5_princ_realm) && defined(krb5_princ_set_realm) /* MIT */ krb5_error_code ret; krb5_data data; krb5_data *old_data; old_data = krb5_princ_realm(context, principal); ret = smb_krb5_copy_data_contents(&data, realm, strlen(realm)); if (ret) { return ret; } /* free realm before setting */ free(old_data->data); krb5_princ_set_realm(context, principal, &data); return ret; #else #error UNKNOWN_PRINC_SET_REALM_FUNCTION #endif } /** * @brief Get the realm from the service hostname. * * This function will look for a domain realm mapping in the [domain_realm] * section of the krb5.conf first and fallback to extract the realm from * the provided service hostname. As a last resort it will return the * provided client_realm. * * @param[in] mem_ctx The talloc context * * @param[in] hostname The service hostname * * @param[in] client_realm If we can not find a mapping, fall back to * this realm. * * @return The realm to use for the service hostname, NULL if a fatal error * occured. */ char *smb_krb5_get_realm_from_hostname(TALLOC_CTX *mem_ctx, const char *hostname, const char *client_realm) { #if defined(HAVE_KRB5_REALM_TYPE) /* Heimdal. */ krb5_realm *realm_list = NULL; #else /* MIT */ char **realm_list = NULL; #endif char *realm = NULL; krb5_error_code kerr; krb5_context ctx = NULL; initialize_krb5_error_table(); if (krb5_init_context(&ctx)) { return NULL; } kerr = krb5_get_host_realm(ctx, hostname, &realm_list); if (kerr == KRB5_ERR_HOST_REALM_UNKNOWN) { realm_list = NULL; kerr = 0; } if (kerr != 0) { DEBUG(3,("kerberos_get_realm_from_hostname %s: " "failed %s\n", hostname ? hostname : "(NULL)", error_message(kerr) )); goto out; } if (realm_list != NULL && realm_list[0] != NULL && realm_list[0][0] != '\0') { realm = talloc_strdup(mem_ctx, realm_list[0]); if (realm == NULL) { goto out; } } else { const char *p = NULL; /* * "dc6.samba2003.example.com" * returns a realm of "SAMBA2003.EXAMPLE.COM" * * "dc6." returns realm as NULL */ p = strchr_m(hostname, '.'); if (p != NULL && p[1] != '\0') { realm = talloc_strdup_upper(mem_ctx, p + 1); if (realm == NULL) { goto out; } } } if (realm == NULL) { realm = talloc_strdup(mem_ctx, client_realm); } out: if (ctx) { if (realm_list) { krb5_free_host_realm(ctx, realm_list); realm_list = NULL; } krb5_free_context(ctx); ctx = NULL; } return realm; } /** * @brief Get an error string from a Kerberos error code. * * @param[in] context The library context. * * @param[in] code The Kerberos error code. * * @param[in] mem_ctx The talloc context to allocate the error string on. * * @return A talloc'ed error string or NULL if an error occurred. * * The caller must free the returned error string with talloc_free() if not * needed anymore */ char *smb_get_krb5_error_message(krb5_context context, krb5_error_code code, TALLOC_CTX *mem_ctx) { char *ret; #if defined(HAVE_KRB5_GET_ERROR_MESSAGE) && defined(HAVE_KRB5_FREE_ERROR_MESSAGE) const char *context_error = krb5_get_error_message(context, code); if (context_error) { ret = talloc_asprintf(mem_ctx, "%s: %s", error_message(code), context_error); krb5_free_error_message(context, context_error); return ret; } #endif ret = talloc_strdup(mem_ctx, error_message(code)); return ret; } /** * @brief Return the kerberos library setting for: libdefaults:allow_weak_crypto * * @param[in] context The library context * * @return True if weak crypto is allowed, false if not. */ krb5_boolean smb_krb5_get_allowed_weak_crypto(krb5_context context) #if defined(HAVE_KRB5_CONFIG_GET_BOOL_DEFAULT) { return krb5_config_get_bool_default(context, NULL, FALSE, "libdefaults", "allow_weak_crypto", NULL); } #elif defined(HAVE_PROFILE_H) && defined(HAVE_KRB5_GET_PROFILE) { #include krb5_error_code ret; krb5_boolean ret_default = false; profile_t profile; int ret_profile; ret = krb5_get_profile(context, &profile); if (ret) { return ret_default; } ret = profile_get_boolean(profile, "libdefaults", "allow_weak_crypto", NULL, /* subsubname */ ret_default, /* def_val */ &ret_profile /* *ret_default */); if (ret) { return ret_default; } profile_release(profile); return ret_profile; } #else #error UNKNOWN_KRB5_CONFIG_ROUTINES #endif /** * @brief Return the type of a krb5_principal * * @param[in] context The library context. * * @param[in] principal The principal to get the type from. * * @return The integer type of the principal. */ int smb_krb5_principal_get_type(krb5_context context, krb5_const_principal principal) { #ifdef HAVE_KRB5_PRINCIPAL_GET_TYPE /* Heimdal */ return krb5_principal_get_type(context, principal); #elif defined(krb5_princ_type) /* MIT */ return krb5_princ_type(context, principal); #else #error UNKNOWN_PRINC_GET_TYPE_FUNCTION #endif } /** * @brief Set the type of a principal * * @param[in] context The library context * * @param[inout] principal The principal to set the type for. * * @param[in] type The principal type to set. */ void smb_krb5_principal_set_type(krb5_context context, krb5_principal principal, int type) { #ifdef HAVE_KRB5_PRINCIPAL_SET_TYPE /* Heimdal */ krb5_principal_set_type(context, principal, type); #elif defined(krb5_princ_type) /* MIT */ krb5_princ_type(context, principal) = type; #else #error UNKNOWN_PRINC_SET_TYPE_FUNCTION #endif } #if !defined(HAVE_KRB5_WARNX) /** * @brief Log a Kerberos message * * It sends the message to com_err. * * @param[in] context The library context * * @param[in] fmt The message format * * @param[in] ... The message arguments * * @return 0 on success. */ krb5_error_code krb5_warnx(krb5_context context, const char *fmt, ...) { va_list args; va_start(args, fmt); com_err_va("samba-kdc", errno, fmt, args); va_end(args); return 0; } #endif /** * @brief Copy a credential cache. * * @param[in] context The library context. * * @param[in] incc Credential cache to be copied. * * @param[inout] outcc Copy of credential cache to be filled in. * * @return 0 on success, a Kerberos error code otherwise. */ krb5_error_code smb_krb5_cc_copy_creds(krb5_context context, krb5_ccache incc, krb5_ccache outcc) { #ifdef HAVE_KRB5_CC_COPY_CACHE /* Heimdal */ return krb5_cc_copy_cache(context, incc, outcc); #elif defined(HAVE_KRB5_CC_COPY_CREDS) krb5_error_code ret; krb5_principal princ = NULL; ret = krb5_cc_get_principal(context, incc, &princ); if (ret != 0) { return ret; } ret = krb5_cc_initialize(context, outcc, princ); krb5_free_principal(context, princ); if (ret != 0) { return ret; } return krb5_cc_copy_creds(context, incc, outcc); #else #error UNKNOWN_KRB5_CC_COPY_CACHE_OR_CREDS_FUNCTION #endif } /********************************************************** * ADS KRB5 CALLS **********************************************************/ static bool ads_cleanup_expired_creds(krb5_context context, krb5_ccache ccache, krb5_creds *credsp) { krb5_error_code retval; const char *cc_type = krb5_cc_get_type(context, ccache); DEBUG(3, ("ads_cleanup_expired_creds: Ticket in ccache[%s:%s] expiration %s\n", cc_type, krb5_cc_get_name(context, ccache), http_timestring(talloc_tos(), credsp->times.endtime))); /* we will probably need new tickets if the current ones will expire within 10 seconds. */ if (credsp->times.endtime >= (time(NULL) + 10)) return false; /* heimdal won't remove creds from a file ccache, and perhaps we shouldn't anyway, since internally we use memory ccaches, and a FILE one probably means that we're using creds obtained outside of our exectuable */ if (strequal(cc_type, "FILE")) { DEBUG(5, ("ads_cleanup_expired_creds: We do not remove creds from a %s ccache\n", cc_type)); return false; } retval = krb5_cc_remove_cred(context, ccache, 0, credsp); if (retval) { DEBUG(1, ("ads_cleanup_expired_creds: krb5_cc_remove_cred failed, err %s\n", error_message(retval))); /* If we have an error in this, we want to display it, but continue as though we deleted it */ } return true; } /* Allocate and setup the auth context into the state we need. */ static krb5_error_code ads_setup_auth_context(krb5_context context, krb5_auth_context *auth_context) { krb5_error_code retval; retval = krb5_auth_con_init(context, auth_context ); if (retval) { DEBUG(1,("krb5_auth_con_init failed (%s)\n", error_message(retval))); return retval; } /* Ensure this is an addressless ticket. */ retval = krb5_auth_con_setaddrs(context, *auth_context, NULL, NULL); if (retval) { DEBUG(1,("krb5_auth_con_setaddrs failed (%s)\n", error_message(retval))); } return retval; } #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE) static krb5_error_code ads_create_gss_checksum(krb5_data *in_data, /* [inout] */ uint32_t gss_flags) { unsigned int orig_length = in_data->length; unsigned int base_cksum_size = GSSAPI_CHECKSUM_SIZE; char *gss_cksum = NULL; if (orig_length) { /* Extra length field for delgated ticket. */ base_cksum_size += 4; } if ((unsigned int)base_cksum_size + orig_length < (unsigned int)base_cksum_size) { return EINVAL; } gss_cksum = (char *)SMB_MALLOC(base_cksum_size + orig_length); if (gss_cksum == NULL) { return ENOMEM; } memset(gss_cksum, '\0', base_cksum_size + orig_length); SIVAL(gss_cksum, 0, GSSAPI_BNDLENGTH); /* * GSS_C_NO_CHANNEL_BINDINGS means 16 zero bytes. * This matches the behavior of heimdal and mit. * * And it is needed to work against some closed source * SMB servers. * * See bug #7883 */ memset(&gss_cksum[4], 0x00, GSSAPI_BNDLENGTH); SIVAL(gss_cksum, 20, gss_flags); if (orig_length) { SSVAL(gss_cksum, 24, 1); /* The Delegation Option identifier */ SSVAL(gss_cksum, 26, orig_length); /* Copy the kerberos KRB_CRED data */ memcpy(gss_cksum + 28, in_data->data, orig_length); free(in_data->data); in_data->data = NULL; in_data->length = 0; } in_data->data = gss_cksum; in_data->length = base_cksum_size + orig_length; return 0; } #endif /* * We can't use krb5_mk_req because w2k wants the service to be in a particular * format. */ static krb5_error_code ads_krb5_mk_req(krb5_context context, krb5_auth_context *auth_context, const krb5_flags ap_req_options, const char *principal, krb5_ccache ccache, krb5_data *outbuf, time_t *expire_time, const char *impersonate_princ_s) { krb5_error_code retval; krb5_principal server; krb5_principal impersonate_princ = NULL; krb5_creds *credsp; krb5_creds creds; krb5_data in_data; bool creds_ready = false; int i = 0, maxtries = 3; bool ok; ZERO_STRUCT(in_data); retval = smb_krb5_parse_name(context, principal, &server); if (retval != 0) { DEBUG(1,("ads_krb5_mk_req: Failed to parse principal %s\n", principal)); return retval; } if (impersonate_princ_s) { retval = smb_krb5_parse_name(context, impersonate_princ_s, &impersonate_princ); if (retval) { DEBUG(1,("ads_krb5_mk_req: Failed to parse principal %s\n", impersonate_princ_s)); goto cleanup_princ; } } /* obtain ticket & session key */ ZERO_STRUCT(creds); if ((retval = krb5_copy_principal(context, server, &creds.server))) { DEBUG(1,("ads_krb5_mk_req: krb5_copy_principal failed (%s)\n", error_message(retval))); goto cleanup_princ; } retval = krb5_cc_get_principal(context, ccache, &creds.client); if (retval != 0) { /* This can commonly fail on smbd startup with no ticket in the cache. * Report at higher level than 1. */ DEBUG(3,("ads_krb5_mk_req: krb5_cc_get_principal failed (%s)\n", error_message(retval))); goto cleanup_creds; } while (!creds_ready && (i < maxtries)) { retval = smb_krb5_get_credentials(context, ccache, creds.client, creds.server, impersonate_princ, &credsp); if (retval != 0) { DBG_WARNING("smb_krb5_get_credentials failed for %s " "(%s)\n", principal, error_message(retval)); goto cleanup_creds; } /* cope with ticket being in the future due to clock skew */ if ((unsigned)credsp->times.starttime > time(NULL)) { time_t t = time(NULL); int time_offset =(int)((unsigned)credsp->times.starttime-t); DEBUG(4,("ads_krb5_mk_req: Advancing clock by %d seconds to cope with clock skew\n", time_offset)); krb5_set_real_time(context, t + time_offset + 1, 0); } ok = ads_cleanup_expired_creds(context, ccache, credsp); if (!ok) { creds_ready = true; } i++; } DBG_DEBUG("Ticket (%s) in ccache (%s:%s) is valid until: (%s - %u)\n", principal, krb5_cc_get_type(context, ccache), krb5_cc_get_name(context, ccache), http_timestring(talloc_tos(), (unsigned)credsp->times.endtime), (unsigned)credsp->times.endtime); if (expire_time) { *expire_time = (time_t)credsp->times.endtime; } /* Allocate the auth_context. */ retval = ads_setup_auth_context(context, auth_context); if (retval != 0) { DBG_WARNING("ads_setup_auth_context failed (%s)\n", error_message(retval)); goto cleanup_creds; } #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE) { uint32_t gss_flags = 0; if (credsp->ticket_flags & TKT_FLG_OK_AS_DELEGATE) { /* * Fetch a forwarded TGT from the KDC so that we can * hand off a 2nd ticket as part of the kerberos * exchange. */ DBG_INFO("Server marked as OK to delegate to, building " "forwardable TGT\n"); retval = krb5_auth_con_setuseruserkey(context, *auth_context, &credsp->keyblock ); if (retval != 0) { DBG_WARNING("krb5_auth_con_setuseruserkey " "failed (%s)\n", error_message(retval)); goto cleanup_creds; } /* Must use a subkey for forwarded tickets. */ retval = krb5_auth_con_setflags(context, *auth_context, KRB5_AUTH_CONTEXT_USE_SUBKEY); if (retval != 0) { DBG_WARNING("krb5_auth_con_setflags failed (%s)\n", error_message(retval)); goto cleanup_creds; } retval = krb5_fwd_tgt_creds(context,/* Krb5 context [in] */ *auth_context, /* Authentication context [in] */ discard_const_p(char, KRB5_TGS_NAME), /* Ticket service name ("krbtgt") [in] */ credsp->client, /* Client principal for the tgt [in] */ credsp->server, /* Server principal for the tgt [in] */ ccache, /* Credential cache to use for storage [in] */ 1, /* Turn on for "Forwardable ticket" [in] */ &in_data ); /* Resulting response [out] */ if (retval) { DBG_INFO("krb5_fwd_tgt_creds failed (%s)\n", error_message(retval)); /* * This is not fatal. Delete the *auth_context and continue * with krb5_mk_req_extended to get a non-forwardable ticket. */ if (in_data.data) { free( in_data.data ); in_data.data = NULL; in_data.length = 0; } krb5_auth_con_free(context, *auth_context); *auth_context = NULL; retval = ads_setup_auth_context(context, auth_context); if (retval != 0) { DBG_WARNING("ads_setup_auth_context failed (%s)\n", error_message(retval)); goto cleanup_creds; } } else { /* We got a delegated ticket. */ gss_flags |= GSS_C_DELEG_FLAG; } } /* Frees and reallocates in_data into a GSS checksum blob. */ retval = ads_create_gss_checksum(&in_data, gss_flags); if (retval != 0) { goto cleanup_data; } /* We always want GSS-checksum types. */ retval = krb5_auth_con_set_req_cksumtype(context, *auth_context, GSSAPI_CHECKSUM ); if (retval != 0) { DEBUG(1,("krb5_auth_con_set_req_cksumtype failed (%s)\n", error_message(retval))); goto cleanup_data; } } #endif retval = krb5_mk_req_extended(context, auth_context, ap_req_options, &in_data, credsp, outbuf); if (retval != 0) { DBG_WARNING("krb5_mk_req_extended failed (%s)\n", error_message(retval)); } #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE) cleanup_data: #endif if (in_data.data) { free( in_data.data ); in_data.length = 0; } krb5_free_creds(context, credsp); cleanup_creds: krb5_free_cred_contents(context, &creds); cleanup_princ: krb5_free_principal(context, server); if (impersonate_princ) { krb5_free_principal(context, impersonate_princ); } return retval; } /* get a kerberos5 ticket for the given service */ int ads_krb5_cli_get_ticket(TALLOC_CTX *mem_ctx, const char *principal, time_t time_offset, DATA_BLOB *ticket, DATA_BLOB *session_key_krb5, uint32_t extra_ap_opts, const char *ccname, time_t *tgs_expire, const char *impersonate_princ_s) { krb5_error_code retval; krb5_data packet; krb5_context context = NULL; krb5_ccache ccdef = NULL; krb5_auth_context auth_context = NULL; krb5_enctype enc_types[] = { #ifdef HAVE_ENCTYPE_AES256_CTS_HMAC_SHA1_96 ENCTYPE_AES256_CTS_HMAC_SHA1_96, #endif #ifdef HAVE_ENCTYPE_AES128_CTS_HMAC_SHA1_96 ENCTYPE_AES128_CTS_HMAC_SHA1_96, #endif ENCTYPE_ARCFOUR_HMAC, ENCTYPE_DES_CBC_MD5, ENCTYPE_DES_CBC_CRC, ENCTYPE_NULL}; bool ok; initialize_krb5_error_table(); retval = krb5_init_context(&context); if (retval != 0) { DBG_WARNING("krb5_init_context failed (%s)\n", error_message(retval)); goto failed; } if (time_offset != 0) { krb5_set_real_time(context, time(NULL) + time_offset, 0); } retval = krb5_cc_resolve(context, ccname ? ccname : krb5_cc_default_name(context), &ccdef); if (retval != 0) { DBG_WARNING("krb5_cc_default failed (%s)\n", error_message(retval)); goto failed; } retval = krb5_set_default_tgs_ktypes(context, enc_types); if (retval != 0) { DBG_WARNING("krb5_set_default_tgs_ktypes failed (%s)\n", error_message(retval)); goto failed; } retval = ads_krb5_mk_req(context, &auth_context, AP_OPTS_USE_SUBKEY | (krb5_flags)extra_ap_opts, principal, ccdef, &packet, tgs_expire, impersonate_princ_s); if (retval != 0) { goto failed; } ok = smb_krb5_get_smb_session_key(mem_ctx, context, auth_context, session_key_krb5, false); if (!ok) { retval = ENOMEM; goto failed; } *ticket = data_blob_talloc(mem_ctx, packet.data, packet.length); smb_krb5_free_data_contents(context, &packet); failed: if (context) { if (ccdef) { krb5_cc_close(context, ccdef); } if (auth_context) { krb5_auth_con_free(context, auth_context); } krb5_free_context(context); } return retval; } #else /* HAVE_KRB5 */ /* This saves a few linking headaches */ int ads_krb5_cli_get_ticket(TALLOC_CTX *mem_ctx, const char *principal, time_t time_offset, DATA_BLOB *ticket, DATA_BLOB *session_key_krb5, uint32_t extra_ap_opts, const char *ccname, time_t *tgs_expire, const char *impersonate_princ_s) { DEBUG(0,("NO KERBEROS SUPPORT\n")); return 1; } #endif /* HAVE_KRB5 */