/* SSSD Kerberos 5 Backend Module -- tgt_req and changepw child Authors: Sumit Bose Copyright (C) 2009-2010 Red Hat 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 #include #include #include #include #include "util/util.h" #include "util/sss_krb5.h" #include "util/user_info_msg.h" #include "util/child_common.h" #include "providers/dp_backend.h" #include "providers/krb5/krb5_auth.h" #include "providers/krb5/krb5_utils.h" #include "sss_cli.h" #define SSSD_KRB5_CHANGEPW_PRINCIPAL "kadmin/changepw" struct krb5_req { krb5_context ctx; krb5_principal princ; char* name; krb5_creds *creds; krb5_get_init_creds_opt *options; struct pam_data *pd; char *realm; char *ccname; char *keytab; bool validate; bool send_pac; bool use_enterprise_princ; char *fast_ccname; const char *upn; uid_t uid; gid_t gid; }; static krb5_context krb5_error_ctx; #define KRB5_CHILD_DEBUG(level, error) KRB5_DEBUG(level, krb5_error_ctx, error) static void set_changepw_options(krb5_context ctx, krb5_get_init_creds_opt *options) { sss_krb5_get_init_creds_opt_set_canonicalize(options, 0); krb5_get_init_creds_opt_set_forwardable(options, 0); krb5_get_init_creds_opt_set_proxiable(options, 0); krb5_get_init_creds_opt_set_renew_life(options, 0); krb5_get_init_creds_opt_set_tkt_life(options, 5*60); } static errno_t sss_send_pac(krb5_authdata **pac_authdata) { struct sss_cli_req_data sss_data; int ret; int errnop; sss_data.len = pac_authdata[0]->length; sss_data.data = pac_authdata[0]->contents; ret = sss_pac_make_request(SSS_PAC_ADD_PAC_USER, &sss_data, NULL, NULL, &errnop); if (ret != NSS_STATUS_SUCCESS || errnop != 0) { DEBUG(SSSDBG_OP_FAILURE, ("sss_pac_make_request failed [%d][%d].\n", ret, errnop)); return EIO; } return EOK; } static void sss_krb5_expire_callback_func(krb5_context context, void *data, krb5_timestamp password_expiration, krb5_timestamp account_expiration, krb5_boolean is_last_req) { int ret; uint32_t *blob; long exp_time; struct krb5_req *kr = talloc_get_type(data, struct krb5_req); if (password_expiration == 0) { return; } exp_time = password_expiration - time(NULL); if (exp_time < 0 || exp_time > UINT32_MAX) { DEBUG(1, ("Time to expire out of range.\n")); return; } DEBUG(SSSDBG_TRACE_INTERNAL, ("exp_time: [%ld]\n", exp_time)); blob = talloc_array(kr->pd, uint32_t, 2); if (blob == NULL) { DEBUG(1, ("talloc_size failed.\n")); return; } blob[0] = SSS_PAM_USER_INFO_EXPIRE_WARN; blob[1] = (uint32_t) exp_time; ret = pam_add_response(kr->pd, SSS_PAM_USER_INFO, 2 * sizeof(uint32_t), (uint8_t *) blob); if (ret != EOK) { DEBUG(1, ("pam_add_response failed.\n")); } return; } #ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_SET_RESPONDER /* * TODO: These features generally would requires a significant refactoring * of SSSD and MIT krb5 doesn't support them anyway. They are listed here * simply as a reminder of things that might become future feature potential. * * 1. tokeninfo selection * 2. challenge * 3. discreet token/pin prompting * 4. interactive otp format correction * 5. nextOTP * */ typedef int (*checker)(int c); static inline checker pick_checker(int format) { switch (format) { case KRB5_RESPONDER_OTP_FORMAT_DECIMAL: return isdigit; case KRB5_RESPONDER_OTP_FORMAT_HEXADECIMAL: return isxdigit; case KRB5_RESPONDER_OTP_FORMAT_ALPHANUMERIC: return isalnum; } return NULL; } static int token_pin_destructor(char *mem) { safezero(mem, strlen(mem)); return 0; } static krb5_error_code tokeninfo_matches(TALLOC_CTX *mem_ctx, const krb5_responder_otp_tokeninfo *ti, const char *pwd, size_t len, char **out_token, char **out_pin) { char *token = NULL, *pin = NULL; checker check = NULL; int i; if (ti->flags & KRB5_RESPONDER_OTP_FLAGS_NEXTOTP) { return ENOTSUP; } if (ti->challenge != NULL) { return ENOTSUP; } /* This is a non-sensical value. */ if (ti->length == 0) { return EPROTO; } if (ti->flags & KRB5_RESPONDER_OTP_FLAGS_COLLECT_TOKEN) { /* ASSUMPTION: authtok has one of the following formats: * 1. TokenValue * 2. PIN+TokenValue */ token = talloc_strndup(mem_ctx, pwd, len); if (token == NULL) { return ENOMEM; } talloc_set_destructor(token, token_pin_destructor); if (ti->flags & KRB5_RESPONDER_OTP_FLAGS_COLLECT_PIN) { /* If the server desires a separate pin, we will split it. * ASSUMPTION: Format of authtok is PIN+TokenValue. */ if (ti->flags & KRB5_RESPONDER_OTP_FLAGS_SEPARATE_PIN) { if (ti->length < 1) { talloc_free(token); return ENOTSUP; } if (ti->length >= len) { talloc_free(token); return EMSGSIZE; } /* Copy the PIN from the front of the value. */ pin = talloc_strndup(NULL, pwd, len - ti->length); if (pin == NULL) { talloc_free(token); return ENOMEM; } talloc_set_destructor(pin, token_pin_destructor); /* Remove the PIN from the front of the token value. */ memmove(token, token + len - ti->length, ti->length + 1); check = pick_checker(ti->format); } else { if (ti->length > 0 && ti->length > len) { talloc_free(token); return EMSGSIZE; } } } else { if (ti->length > 0 && ti->length != len) { talloc_free(token); return EMSGSIZE; } check = pick_checker(ti->format); } } else { pin = talloc_strndup(mem_ctx, pwd, len); if (pin == NULL) { return ENOMEM; } talloc_set_destructor(pin, token_pin_destructor); } /* If check is set, we need to verify the contents of the token. */ for (i = 0; check != NULL && token[i] != '\0'; i++) { if (!check(token[i])) { talloc_free(token); talloc_free(pin); return EBADMSG; } } *out_token = token; *out_pin = pin; return 0; } static krb5_error_code answer_otp(krb5_context ctx, struct krb5_req *kr, krb5_responder_context rctx) { krb5_responder_otp_challenge *chl; char *token = NULL, *pin = NULL; const char *pwd = NULL; krb5_error_code ret; size_t i, len; ret = krb5_responder_otp_get_challenge(ctx, rctx, &chl); if (ret != EOK || chl == NULL) { /* Either an error, or nothing to do. */ return ret; } if (chl->tokeninfo == NULL || chl->tokeninfo[0] == NULL) { /* No tokeninfos? Absurd! */ ret = EINVAL; goto done; } /* Validate our assumptions about the contents of authtok. */ ret = sss_authtok_get_password(kr->pd->authtok, &pwd, &len); if (ret != EOK) goto done; /* Find the first supported tokeninfo which matches our authtoken. */ for (i = 0; chl->tokeninfo[i] != NULL; i++) { ret = tokeninfo_matches(kr, chl->tokeninfo[i], pwd, len, &token, &pin); if (ret == EOK) { break; } switch (ret) { case EBADMSG: case EMSGSIZE: case ENOTSUP: case EPROTO: break; default: goto done; } } if (chl->tokeninfo[i] == NULL) { DEBUG(SSSDBG_CRIT_FAILURE, ("No tokeninfos found which match our credentials.\n")); ret = EOK; goto done; } if (chl->tokeninfo[i]->flags & KRB5_RESPONDER_OTP_FLAGS_COLLECT_TOKEN) { /* Don't let SSSD cache the OTP authtok since it is single-use. */ ret = pam_add_response(kr->pd, SSS_OTP, 0, NULL); if (ret != EOK) { DEBUG(1, ("pam_add_response failed.\n")); goto done; } } /* Respond with the appropriate answer. */ ret = krb5_responder_otp_set_answer(ctx, rctx, i, token, pin); done: talloc_free(token); talloc_free(pin); krb5_responder_otp_challenge_free(ctx, rctx, chl); return ret; } static krb5_error_code sss_krb5_responder(krb5_context ctx, void *data, krb5_responder_context rctx) { struct krb5_req *kr = talloc_get_type(data, struct krb5_req); if (kr == NULL) { return EINVAL; } return answer_otp(ctx, kr, rctx); } #endif static krb5_error_code sss_krb5_prompter(krb5_context context, void *data, const char *name, const char *banner, int num_prompts, krb5_prompt prompts[]) { int ret; struct krb5_req *kr = talloc_get_type(data, struct krb5_req); if (num_prompts != 0) { DEBUG(1, ("Cannot handle password prompts.\n")); return KRB5_LIBOS_CANTREADPWD; } if (banner == NULL || *banner == '\0') { DEBUG(5, ("Prompter called with empty banner, nothing to do.\n")); return EOK; } DEBUG(SSSDBG_FUNC_DATA, ("Prompter called with [%s].\n", banner)); ret = pam_add_response(kr->pd, SSS_PAM_TEXT_MSG, strlen(banner)+1, (const uint8_t *) banner); if (ret != EOK) { DEBUG(1, ("pam_add_response failed.\n")); } return EOK; } static krb5_error_code create_empty_cred(krb5_context ctx, krb5_principal princ, krb5_creds **_cred) { krb5_error_code kerr; krb5_creds *cred = NULL; krb5_data *krb5_realm; cred = calloc(sizeof(krb5_creds), 1); if (cred == NULL) { DEBUG(1, ("calloc failed.\n")); return ENOMEM; } kerr = krb5_copy_principal(ctx, princ, &cred->client); if (kerr != 0) { DEBUG(1, ("krb5_copy_principal failed.\n")); goto done; } krb5_realm = krb5_princ_realm(ctx, princ); kerr = krb5_build_principal_ext(ctx, &cred->server, krb5_realm->length, krb5_realm->data, KRB5_TGS_NAME_SIZE, KRB5_TGS_NAME, krb5_realm->length, krb5_realm->data, 0); if (kerr != 0) { DEBUG(1, ("krb5_build_principal_ext failed.\n")); goto done; } DEBUG(SSSDBG_TRACE_INTERNAL, ("Created empty krb5_creds.\n")); done: if (kerr != 0) { krb5_free_cred_contents(ctx, cred); free(cred); } else { *_cred = cred; } return kerr; } static errno_t handle_randomized(char *in) { size_t ccname_len; char *ccname = NULL; int ret; int fd; mode_t old_umask; /* We only treat the FILE type case in a special way due to the history * of storing FILE type ccache in /tmp and associated security issues */ if (in[0] == '/') { ccname = in; } else if (strncmp(in, "FILE:", 5) == 0) { ccname = in + 5; } else { return EOK; } ccname_len = strlen(ccname); if (ccname_len >= 6 && strcmp(ccname + (ccname_len - 6), "XXXXXX") == 0) { /* NOTE: this call is only used to create a unique name, as later * krb5_cc_initialize() will unlink and recreate the file. * This is ok because this part of the code is called with * privileges already dropped when handling user ccache, or the ccache * is stored in a private directory. So we do not have huge issues if * something races, we mostly care only about not accidentally use * an existing name and thus failing in the process of saving the * cache. Malicious races can only be avoided by libkrb5 itself. */ old_umask = umask(077); fd = mkstemp(ccname); umask(old_umask); if (fd == -1) { ret = errno; DEBUG(SSSDBG_CRIT_FAILURE, ("mkstemp(\"%s\") failed!\n", ccname)); return ret; } } return EOK; } /* NOTE: callers rely on 'name' being *changed* if it needs to be randomized, * as they will then send the name back to the new name via the return call * k5c_attach_ccname_msg(). Callers will send in a copy of the name if they * do not care for changes. */ static krb5_error_code create_ccache(char *ccname, krb5_creds *creds) { krb5_context kctx = NULL; krb5_ccache kcc = NULL; const char *type; krb5_error_code kerr; #ifdef HAVE_KRB5_CC_COLLECTION krb5_ccache cckcc; bool switch_to_cc = false; #endif /* Set a restrictive umask, just in case we end up creating any file */ umask(077); /* we create a new context here as the main process one may have been * opened as root and contain possibly references (even open handles ?) * to resources we do not have or do not want to have access to */ kerr = krb5_init_context(&kctx); if (kerr) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return ERR_INTERNAL; } kerr = handle_randomized(ccname); if (kerr) goto done; kerr = krb5_cc_resolve(kctx, ccname, &kcc); if (kerr) goto done; type = krb5_cc_get_type(kctx, kcc); DEBUG(SSSDBG_TRACE_ALL, ("Initializing ccache of type [%s]\n", type)); #ifdef HAVE_KRB5_CC_COLLECTION if (krb5_cc_support_switch(kctx, type)) { kerr = krb5_cc_set_default_name(kctx, ccname); if (kerr) goto done; kerr = krb5_cc_cache_match(kctx, creds->client, &cckcc); if (kerr == KRB5_CC_NOTFOUND) { kerr = krb5_cc_new_unique(kctx, type, NULL, &cckcc); switch_to_cc = true; } if (kerr) goto done; krb5_cc_close(kctx, kcc); kcc = cckcc; } #endif kerr = krb5_cc_initialize(kctx, kcc, creds->client); if (kerr) goto done; kerr = krb5_cc_store_cred(kctx, kcc, creds); if (kerr) goto done; #ifdef HAVE_KRB5_CC_COLLECTION if (switch_to_cc) { kerr = krb5_cc_switch(kctx, kcc); if (kerr) goto done; } #endif done: if (kcc) { /* FIXME: should we krb5_cc_destroy in case of error ? */ krb5_cc_close(kctx, kcc); } return kerr; } static errno_t pack_response_packet(TALLOC_CTX *mem_ctx, errno_t error, struct response_data *resp_list, uint8_t **_buf, size_t *_len) { uint8_t *buf; size_t size = 0; size_t p = 0; struct response_data *pdr; /* A buffer with the following structure must be created: * int32_t status of the request (required) * message (zero or more) * * A message consists of: * int32_t type of the message * int32_t length of the following data * uint8_t[len] data */ size = sizeof(int32_t); for (pdr = resp_list; pdr != NULL; pdr = pdr->next) { size += 2*sizeof(int32_t) + pdr->len; } buf = talloc_array(mem_ctx, uint8_t, size); if (!buf) { DEBUG(1, ("Insufficient memory to create message.\n")); return ENOMEM; } SAFEALIGN_SET_INT32(&buf[p], error, &p); for (pdr = resp_list; pdr != NULL; pdr = pdr->next) { SAFEALIGN_SET_INT32(&buf[p], pdr->type, &p); SAFEALIGN_SET_INT32(&buf[p], pdr->len, &p); safealign_memcpy(&buf[p], pdr->data, pdr->len, &p); } DEBUG(SSSDBG_TRACE_INTERNAL, ("response packet size: [%zu]\n", p)); *_buf = buf; *_len = p; return EOK; } static errno_t k5c_attach_ccname_msg(struct krb5_req *kr) { char *msg = NULL; int ret; if (kr->ccname == NULL) { DEBUG(1, ("Error obtaining ccname.\n")); return ERR_INTERNAL; } msg = talloc_asprintf(kr, "%s=%s",CCACHE_ENV_NAME, kr->ccname); if (msg == NULL) { DEBUG(1, ("talloc_asprintf failed.\n")); return ENOMEM; } ret = pam_add_response(kr->pd, SSS_PAM_ENV_ITEM, strlen(msg) + 1, (uint8_t *)msg); talloc_zfree(msg); return ret; } static errno_t k5c_send_data(struct krb5_req *kr, int fd, errno_t error) { size_t written; uint8_t *buf; size_t len; int ret; ret = pack_response_packet(kr, error, kr->pd->resp_list, &buf, &len); if (ret != EOK) { DEBUG(1, ("pack_response_packet failed.\n")); return ret; } errno = 0; written = sss_atomic_write_s(fd, buf, len); if (written == -1) { ret = errno; DEBUG(SSSDBG_CRIT_FAILURE, ("write failed [%d][%s].\n", ret, strerror(ret))); return ret; } if (written != len) { DEBUG(SSSDBG_CRIT_FAILURE, ("Write error, wrote [%zu] bytes, expected [%zu]\n", written, len)); return EOK; } DEBUG(SSSDBG_TRACE_ALL, ("Response sent.\n")); return EOK; } static errno_t add_ticket_times_and_upn_to_response(struct krb5_req *kr) { int ret; int64_t t[4]; krb5_error_code kerr; char *upn = NULL; unsigned int upn_len = 0; t[0] = (int64_t) kr->creds->times.authtime; t[1] = (int64_t) kr->creds->times.starttime; t[2] = (int64_t) kr->creds->times.endtime; t[3] = (int64_t) kr->creds->times.renew_till; ret = pam_add_response(kr->pd, SSS_KRB5_INFO_TGT_LIFETIME, 4*sizeof(int64_t), (uint8_t *) t); if (ret != EOK) { DEBUG(1, ("pack_response_packet failed.\n")); goto done; } kerr = krb5_unparse_name_ext(kr->ctx, kr->creds->client, &upn, &upn_len); if (kerr != 0) { DEBUG(SSSDBG_OP_FAILURE, ("krb5_unparse_name failed.\n")); goto done; } ret = pam_add_response(kr->pd, SSS_KRB5_INFO_UPN, upn_len, (uint8_t *) upn); krb5_free_unparsed_name(kr->ctx, upn); if (ret != EOK) { DEBUG(1, ("pack_response_packet failed.\n")); goto done; } done: return ret; } static krb5_error_code validate_tgt(struct krb5_req *kr) { krb5_error_code kerr; krb5_error_code kt_err; char *principal = NULL; krb5_keytab keytab; krb5_kt_cursor cursor; krb5_keytab_entry entry; krb5_verify_init_creds_opt opt; krb5_principal validation_princ = NULL; bool realm_entry_found = false; krb5_ccache validation_ccache = NULL; krb5_authdata **pac_authdata = NULL; memset(&keytab, 0, sizeof(keytab)); kerr = krb5_kt_resolve(kr->ctx, kr->keytab, &keytab); if (kerr != 0) { DEBUG(SSSDBG_CRIT_FAILURE, ("error resolving keytab [%s], " \ "not verifying TGT.\n", kr->keytab)); return kerr; } memset(&cursor, 0, sizeof(cursor)); kerr = krb5_kt_start_seq_get(kr->ctx, keytab, &cursor); if (kerr != 0) { DEBUG(SSSDBG_CRIT_FAILURE, ("error reading keytab [%s], " \ "not verifying TGT.\n", kr->keytab)); return kerr; } /* We look for the first entry from our realm or take the last one */ memset(&entry, 0, sizeof(entry)); while ((kt_err = krb5_kt_next_entry(kr->ctx, keytab, &entry, &cursor)) == 0) { if (validation_princ != NULL) { krb5_free_principal(kr->ctx, validation_princ); validation_princ = NULL; } kerr = krb5_copy_principal(kr->ctx, entry.principal, &validation_princ); if (kerr != 0) { DEBUG(SSSDBG_CRIT_FAILURE, ("krb5_copy_principal failed.\n")); goto done; } kerr = sss_krb5_free_keytab_entry_contents(kr->ctx, &entry); if (kerr != 0) { DEBUG(SSSDBG_MINOR_FAILURE, ("Failed to free keytab entry.\n")); } memset(&entry, 0, sizeof(entry)); if (krb5_realm_compare(kr->ctx, validation_princ, kr->creds->client)) { DEBUG(SSSDBG_TRACE_INTERNAL, ("Found keytab entry with the realm of the credential.\n")); realm_entry_found = true; break; } } if (!realm_entry_found) { DEBUG(SSSDBG_TRACE_INTERNAL, ("Keytab entry with the realm of the credential not found " "in keytab. Using the last entry.\n")); } /* Close the keytab here. Even though we're using cursors, the file * handle is stored in the krb5_keytab structure, and it gets * overwritten when the verify_init_creds() call below creates its own * cursor, creating a leak. */ kerr = krb5_kt_end_seq_get(kr->ctx, keytab, &cursor); if (kerr != 0) { DEBUG(SSSDBG_CRIT_FAILURE, ("krb5_kt_end_seq_get failed, " \ "not verifying TGT.\n")); goto done; } /* check if we got any errors from krb5_kt_next_entry */ if (kt_err != 0 && kt_err != KRB5_KT_END) { DEBUG(SSSDBG_CRIT_FAILURE, ("error reading keytab [%s], " \ "not verifying TGT.\n", kr->keytab)); goto done; } /* Get the principal to which the key belongs, for logging purposes. */ principal = NULL; kerr = krb5_unparse_name(kr->ctx, validation_princ, &principal); if (kerr != 0) { DEBUG(SSSDBG_CRIT_FAILURE, ("internal error parsing principal name, " "not verifying TGT.\n")); KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); goto done; } krb5_verify_init_creds_opt_init(&opt); kerr = krb5_verify_init_creds(kr->ctx, kr->creds, validation_princ, keytab, &validation_ccache, &opt); if (kerr == 0) { DEBUG(SSSDBG_TRACE_FUNC, ("TGT verified using key for [%s].\n", principal)); } else { DEBUG(SSSDBG_CRIT_FAILURE ,("TGT failed verification using key " \ "for [%s].\n", principal)); goto done; } /* Try to find and send the PAC to the PAC responder. * Failures are not critical. */ if (kr->send_pac) { kerr = sss_extract_pac(kr->ctx, validation_ccache, validation_princ, kr->creds->client, keytab, &pac_authdata); if (kerr != 0) { DEBUG(SSSDBG_OP_FAILURE, ("sss_extract_and_send_pac failed, group " \ "membership for user with principal [%s] " \ "might not be correct.\n", kr->name)); kerr = 0; goto done; } kerr = sss_send_pac(pac_authdata); krb5_free_authdata(kr->ctx, pac_authdata); if (kerr != 0) { DEBUG(SSSDBG_OP_FAILURE, ("sss_send_pac failed, group " \ "membership for user with principal [%s] " \ "might not be correct.\n", kr->name)); kerr = 0; } } done: if (validation_ccache != NULL) { krb5_cc_destroy(kr->ctx, validation_ccache); } if (krb5_kt_close(kr->ctx, keytab) != 0) { DEBUG(SSSDBG_MINOR_FAILURE, ("krb5_kt_close failed")); } if (validation_princ != NULL) { krb5_free_principal(kr->ctx, validation_princ); } if (principal != NULL) { sss_krb5_free_unparsed_name(kr->ctx, principal); } return kerr; } static void krb5_set_canonicalize(krb5_get_init_creds_opt *opts) { int canonicalize = 0; char *tmp_str; tmp_str = getenv(SSSD_KRB5_CANONICALIZE); if (tmp_str != NULL && strcasecmp(tmp_str, "true") == 0) { canonicalize = 1; } DEBUG(SSSDBG_CONF_SETTINGS, ("%s is set to [%s]\n", SSSD_KRB5_CANONICALIZE, tmp_str ? tmp_str : "not set")); sss_krb5_get_init_creds_opt_set_canonicalize(opts, canonicalize); } static krb5_error_code get_and_save_tgt_with_keytab(krb5_context ctx, krb5_principal princ, krb5_keytab keytab, char *ccname) { krb5_error_code kerr = 0; krb5_creds creds; krb5_get_init_creds_opt options; memset(&creds, 0, sizeof(creds)); memset(&options, 0, sizeof(options)); krb5_get_init_creds_opt_set_address_list(&options, NULL); krb5_get_init_creds_opt_set_forwardable(&options, 0); krb5_get_init_creds_opt_set_proxiable(&options, 0); krb5_set_canonicalize(&options); kerr = krb5_get_init_creds_keytab(ctx, &creds, princ, keytab, 0, NULL, &options); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } /* Use the updated principal in the creds in case canonicalized */ kerr = create_ccache(ccname, &creds); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); goto done; } kerr = 0; done: krb5_free_cred_contents(ctx, &creds); return kerr; } static krb5_error_code get_and_save_tgt(struct krb5_req *kr, const char *password) { const char *realm_name; int realm_length; krb5_error_code kerr; char *cc_name; kerr = sss_krb5_get_init_creds_opt_set_expire_callback(kr->ctx, kr->options, sss_krb5_expire_callback_func, kr); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); DEBUG(1, ("Failed to set expire callback, continue without.\n")); } sss_krb5_princ_realm(kr->ctx, kr->princ, &realm_name, &realm_length); DEBUG(SSSDBG_TRACE_FUNC, ("Attempting kinit for realm [%s]\n",realm_name)); kerr = krb5_get_init_creds_password(kr->ctx, kr->creds, kr->princ, discard_const(password), sss_krb5_prompter, kr, 0, NULL, kr->options); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } if (kr->validate) { kerr = validate_tgt(kr); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } } else { DEBUG(SSSDBG_CONF_SETTINGS, ("TGT validation is disabled.\n")); } if (kr->validate || kr->fast_ccname != NULL) { /* We drop root privileges which were needed to read the keytab file * for the validation of the credentials or for FAST here to run the * ccache I/O operations with user privileges. */ kerr = become_user(kr->uid, kr->gid); if (kerr != 0) { DEBUG(1, ("become_user failed.\n")); return kerr; } } /* If kr->ccname is cache collection (DIR:/...), we want to work * directly with file ccache (DIR::/...), but cache collection * should be returned back to back end. */ cc_name = sss_get_ccache_name_for_principal(kr->pd, kr->ctx, kr->creds->client, kr->ccname); if (cc_name == NULL) { cc_name = kr->ccname; } /* Use the updated principal in the creds in case canonicalized */ kerr = create_ccache(cc_name, kr->creds); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); goto done; } kerr = add_ticket_times_and_upn_to_response(kr); if (kerr != 0) { DEBUG(1, ("add_ticket_times_and_upn_to_response failed.\n")); } kerr = 0; done: krb5_free_cred_contents(kr->ctx, kr->creds); return kerr; } static errno_t map_krb5_error(krb5_error_code kerr) { if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); } switch (kerr) { case 0: return ERR_OK; case KRB5_LIBOS_CANTREADPWD: return ERR_NO_CREDS; case KRB5_KDC_UNREACH: case KRB5_REALM_CANT_RESOLVE: return ERR_NETWORK_IO; case KRB5KDC_ERR_CLIENT_REVOKED: return ERR_ACCOUNT_EXPIRED; case KRB5KDC_ERR_KEY_EXP: return ERR_CREDS_EXPIRED; case KRB5KRB_AP_ERR_BAD_INTEGRITY: return ERR_AUTH_FAILED; /* ERR_CREDS_INVALID is used to indicate to the IPA provider that trying * password migration would make sense. All Kerberos error codes which can * be seen while migrating LDAP users to IPA should be added here. */ case KRB5_PROG_ETYPE_NOSUPP: case KRB5_PREAUTH_FAILED: case KRB5KDC_ERR_PREAUTH_FAILED: return ERR_CREDS_INVALID; default: return ERR_INTERNAL; } } static errno_t changepw_child(struct krb5_req *kr, bool prelim) { int ret; krb5_error_code kerr = 0; const char *password = NULL; const char *newpassword = NULL; int result_code = -1; krb5_data result_code_string; krb5_data result_string; char *user_error_message = NULL; size_t user_resp_len; uint8_t *user_resp; krb5_prompter_fct prompter = NULL; const char *realm_name; int realm_length; size_t msg_len; uint8_t *msg; DEBUG(SSSDBG_TRACE_LIBS, ("Password change operation\n")); ret = sss_authtok_get_password(kr->pd->authtok, &password, NULL); if (ret != EOK) { DEBUG(1, ("Failed to fetch current password [%d] %s.\n", ret, strerror(ret))); return ERR_NO_CREDS; } if (!prelim) { /* We do not need a password expiration warning here. */ prompter = sss_krb5_prompter; } set_changepw_options(kr->ctx, kr->options); sss_krb5_princ_realm(kr->ctx, kr->princ, &realm_name, &realm_length); DEBUG(SSSDBG_TRACE_FUNC, ("Attempting kinit for realm [%s]\n",realm_name)); kerr = krb5_get_init_creds_password(kr->ctx, kr->creds, kr->princ, discard_const(password), prompter, kr, 0, SSSD_KRB5_CHANGEPW_PRINCIPAL, kr->options); if (kerr != 0) { ret = pack_user_info_chpass_error(kr->pd, "Old password not accepted.", &msg_len, &msg); if (ret != EOK) { DEBUG(SSSDBG_CRIT_FAILURE, ("pack_user_info_chpass_error failed.\n")); } else { ret = pam_add_response(kr->pd, SSS_PAM_USER_INFO, msg_len, msg); if (ret != EOK) { DEBUG(SSSDBG_CRIT_FAILURE, ("pam_add_response failed.\n")); } } return kerr; } sss_authtok_set_empty(kr->pd->authtok); if (prelim) { DEBUG(SSSDBG_TRACE_LIBS, ("Initial authentication for change password operation " "successful.\n")); krb5_free_cred_contents(kr->ctx, kr->creds); return EOK; } ret = sss_authtok_get_password(kr->pd->newauthtok, &newpassword, NULL); if (ret != EOK) { DEBUG(1, ("Failed to fetch new password [%d] %s.\n", ret, strerror(ret))); return ERR_NO_CREDS; } memset(&result_code_string, 0, sizeof(krb5_data)); memset(&result_string, 0, sizeof(krb5_data)); kerr = krb5_change_password(kr->ctx, kr->creds, discard_const(newpassword), &result_code, &result_code_string, &result_string); if (kerr == KRB5_KDC_UNREACH) { return ERR_NETWORK_IO; } if (kerr != 0 || result_code != 0) { if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); } if (result_code_string.length > 0) { DEBUG(1, ("krb5_change_password failed [%d][%.*s].\n", result_code, result_code_string.length, result_code_string.data)); user_error_message = talloc_strndup(kr->pd, result_code_string.data, result_code_string.length); if (user_error_message == NULL) { DEBUG(1, ("talloc_strndup failed.\n")); } } if (result_string.length > 0 && result_string.data[0] != '\0') { DEBUG(1, ("krb5_change_password failed [%d][%.*s].\n", result_code, result_string.length, result_string.data)); talloc_free(user_error_message); user_error_message = talloc_strndup(kr->pd, result_string.data, result_string.length); if (user_error_message == NULL) { DEBUG(1, ("talloc_strndup failed.\n")); } } else if (result_code == KRB5_KPASSWD_SOFTERROR) { user_error_message = talloc_strdup(kr->pd, "Please make sure the " "password meets the complexity constraints."); if (user_error_message == NULL) { DEBUG(SSSDBG_CRIT_FAILURE, ("talloc_strndup failed.\n")); } } if (user_error_message != NULL) { ret = pack_user_info_chpass_error(kr->pd, user_error_message, &user_resp_len, &user_resp); if (ret != EOK) { DEBUG(1, ("pack_user_info_chpass_error failed.\n")); } else { ret = pam_add_response(kr->pd, SSS_PAM_USER_INFO, user_resp_len, user_resp); if (ret != EOK) { DEBUG(1, ("pack_response_packet failed.\n")); } } } return ERR_CHPASS_FAILED; } krb5_free_cred_contents(kr->ctx, kr->creds); kerr = get_and_save_tgt(kr, newpassword); sss_authtok_set_empty(kr->pd->newauthtok); if (kerr == 0) { kerr = k5c_attach_ccname_msg(kr); } return map_krb5_error(kerr); } static errno_t tgt_req_child(struct krb5_req *kr) { const char *password = NULL; krb5_error_code kerr; int ret; DEBUG(SSSDBG_TRACE_LIBS, ("Attempting to get a TGT\n")); ret = sss_authtok_get_password(kr->pd->authtok, &password, NULL); switch (ret) { case EOK: break; case EACCES: DEBUG(SSSDBG_OP_FAILURE, ("Invalid authtok type\n")); return ERR_INVALID_CRED_TYPE; break; default: DEBUG(SSSDBG_OP_FAILURE, ("No credentials available\n")); return ERR_NO_CREDS; break; } kerr = get_and_save_tgt(kr, password); if (kerr != KRB5KDC_ERR_KEY_EXP) { if (kerr == 0) { kerr = k5c_attach_ccname_msg(kr); } ret = map_krb5_error(kerr); goto done; } /* If the password is expired the KDC will always return KRB5KDC_ERR_KEY_EXP regardless if the supplied password is correct or not. In general the password can still be used to get a changepw ticket. So we validate the password by trying to get a changepw ticket. */ DEBUG(SSSDBG_TRACE_LIBS, ("Password was expired\n")); kerr = sss_krb5_get_init_creds_opt_set_expire_callback(kr->ctx, kr->options, NULL, NULL); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); DEBUG(1, ("Failed to unset expire callback, continue ...\n")); } set_changepw_options(kr->ctx, kr->options); kerr = krb5_get_init_creds_password(kr->ctx, kr->creds, kr->princ, discard_const(password), sss_krb5_prompter, kr, 0, SSSD_KRB5_CHANGEPW_PRINCIPAL, kr->options); krb5_free_cred_contents(kr->ctx, kr->creds); if (kerr == 0) { ret = ERR_CREDS_EXPIRED; } else { ret = map_krb5_error(kerr); } done: sss_authtok_set_empty(kr->pd->authtok); return ret; } static errno_t kuserok_child(struct krb5_req *kr) { krb5_boolean access_allowed; krb5_error_code kerr; DEBUG(SSSDBG_TRACE_LIBS, ("Verifying if principal can log in as user\n")); /* krb5_kuserok tries to verify that kr->pd->user is a locally known * account, so we have to unset _SSS_LOOPS to make getpwnam() work. */ if (unsetenv("_SSS_LOOPS") != 0) { DEBUG(1, ("Failed to unset _SSS_LOOPS, " "krb5_kuserok will most certainly fail.\n")); } kerr = krb5_set_default_realm(kr->ctx, kr->realm); if (kerr != 0) { DEBUG(1, ("krb5_set_default_realm failed, " "krb5_kuserok may fail.\n")); } access_allowed = krb5_kuserok(kr->ctx, kr->princ, kr->pd->user); DEBUG(SSSDBG_TRACE_LIBS, ("Access was %s\n", access_allowed ? "allowed" : "denied")); if (access_allowed) { return EOK; } return ERR_AUTH_DENIED; } static errno_t renew_tgt_child(struct krb5_req *kr) { const char *ccname; krb5_ccache ccache = NULL; krb5_error_code kerr; int ret; DEBUG(SSSDBG_TRACE_LIBS, ("Renewing a ticket\n")); ret = sss_authtok_get_ccfile(kr->pd->authtok, &ccname, NULL); if (ret != EOK) { DEBUG(SSSDBG_OP_FAILURE, ("Unsupported authtok type for TGT renewal [%d].\n", sss_authtok_get_type(kr->pd->authtok))); return ERR_INVALID_CRED_TYPE; } kerr = krb5_cc_resolve(kr->ctx, ccname, &ccache); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); goto done; } kerr = krb5_get_renewed_creds(kr->ctx, kr->creds, kr->princ, ccache, NULL); if (kerr != 0) { goto done; } if (kr->validate) { kerr = validate_tgt(kr); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); goto done; } } else { DEBUG(SSSDBG_CONF_SETTINGS, ("TGT validation is disabled.\n")); } if (kr->validate || kr->fast_ccname != NULL) { /* We drop root privileges which were needed to read the keytab file * for the validation of the credentials or for FAST here to run the * ccache I/O operations with user privileges. */ kerr = become_user(kr->uid, kr->gid); if (kerr != 0) { DEBUG(1, ("become_user failed.\n")); goto done; } } kerr = krb5_cc_initialize(kr->ctx, ccache, kr->princ); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); goto done; } kerr = krb5_cc_store_cred(kr->ctx, ccache, kr->creds); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); goto done; } kerr = add_ticket_times_and_upn_to_response(kr); if (kerr != 0) { DEBUG(1, ("add_ticket_times_and_upn_to_response failed.\n")); } kerr = k5c_attach_ccname_msg(kr); done: krb5_free_cred_contents(kr->ctx, kr->creds); if (ccache != NULL) { krb5_cc_close(kr->ctx, ccache); } return map_krb5_error(kerr); } static errno_t create_empty_ccache(struct krb5_req *kr) { krb5_creds *creds = NULL; krb5_error_code kerr; DEBUG(SSSDBG_TRACE_LIBS, ("Creating empty ccache\n")); kerr = create_empty_cred(kr->ctx, kr->princ, &creds); if (kerr == 0) { kerr = create_ccache(kr->ccname, creds); } if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); } else { kerr = k5c_attach_ccname_msg(kr); } krb5_free_creds(kr->ctx, creds); return map_krb5_error(kerr); } static errno_t unpack_authtok(struct sss_auth_token *tok, uint8_t *buf, size_t size, size_t *p) { uint32_t auth_token_type; uint32_t auth_token_length; errno_t ret = EOK; SAFEALIGN_COPY_UINT32_CHECK(&auth_token_type, buf + *p, size, p); SAFEALIGN_COPY_UINT32_CHECK(&auth_token_length, buf + *p, size, p); if ((*p + auth_token_length) > size) { return EINVAL; } switch (auth_token_type) { case SSS_AUTHTOK_TYPE_EMPTY: sss_authtok_set_empty(tok); break; case SSS_AUTHTOK_TYPE_PASSWORD: ret = sss_authtok_set_password(tok, (char *)(buf + *p), 0); break; case SSS_AUTHTOK_TYPE_CCFILE: ret = sss_authtok_set_ccfile(tok, (char *)(buf + *p), 0); break; default: return EINVAL; } if (ret == EOK) { *p += auth_token_length; } return ret; } static errno_t unpack_buffer(uint8_t *buf, size_t size, struct krb5_req *kr, uint32_t *offline) { size_t p = 0; uint32_t len; uint32_t validate; uint32_t send_pac; uint32_t use_enterprise_princ; struct pam_data *pd; errno_t ret; DEBUG(SSSDBG_TRACE_LIBS, ("total buffer size: [%zu]\n", size)); if (!offline || !kr) return EINVAL; pd = create_pam_data(kr); if (pd == NULL) { DEBUG(SSSDBG_CRIT_FAILURE, ("talloc_zero failed.\n")); return ENOMEM; } kr->pd = pd; SAFEALIGN_COPY_UINT32_CHECK(&pd->cmd, buf + p, size, &p); SAFEALIGN_COPY_UINT32_CHECK(&kr->uid, buf + p, size, &p); SAFEALIGN_COPY_UINT32_CHECK(&kr->gid, buf + p, size, &p); SAFEALIGN_COPY_UINT32_CHECK(&validate, buf + p, size, &p); kr->validate = (validate == 0) ? false : true; SAFEALIGN_COPY_UINT32_CHECK(offline, buf + p, size, &p); SAFEALIGN_COPY_UINT32_CHECK(&send_pac, buf + p, size, &p); kr->send_pac = (send_pac == 0) ? false : true; SAFEALIGN_COPY_UINT32_CHECK(&use_enterprise_princ, buf + p, size, &p); kr->use_enterprise_princ = (use_enterprise_princ == 0) ? false : true; SAFEALIGN_COPY_UINT32_CHECK(&len, buf + p, size, &p); if ((p + len ) > size) return EINVAL; kr->upn = talloc_strndup(pd, (char *)(buf + p), len); if (kr->upn == NULL) return ENOMEM; p += len; DEBUG(SSSDBG_CONF_SETTINGS, ("cmd [%d] uid [%llu] gid [%llu] validate [%s] " "enterprise principal [%s] offline [%s] UPN [%s]\n", pd->cmd, (unsigned long long) kr->uid, (unsigned long long) kr->gid, kr->validate ? "true" : "false", kr->use_enterprise_princ ? "true" : "false", *offline ? "true" : "false", kr->upn ? kr->upn : "none")); if (pd->cmd == SSS_PAM_AUTHENTICATE || pd->cmd == SSS_CMD_RENEW || pd->cmd == SSS_PAM_CHAUTHTOK_PRELIM || pd->cmd == SSS_PAM_CHAUTHTOK) { SAFEALIGN_COPY_UINT32_CHECK(&len, buf + p, size, &p); if ((p + len ) > size) return EINVAL; kr->ccname = talloc_strndup(pd, (char *)(buf + p), len); if (kr->ccname == NULL) return ENOMEM; p += len; SAFEALIGN_COPY_UINT32_CHECK(&len, buf + p, size, &p); if ((p + len ) > size) return EINVAL; kr->keytab = talloc_strndup(pd, (char *)(buf + p), len); if (kr->keytab == NULL) return ENOMEM; p += len; ret = unpack_authtok(pd->authtok, buf, size, &p); if (ret) { return ret; } DEBUG(SSSDBG_CONF_SETTINGS, ("ccname: [%s] keytab: [%s]\n", kr->ccname, kr->keytab)); } else { kr->ccname = NULL; kr->keytab = NULL; sss_authtok_set_empty(pd->authtok); } if (pd->cmd == SSS_PAM_CHAUTHTOK) { ret = unpack_authtok(pd->newauthtok, buf, size, &p); if (ret) { return ret; } } else { sss_authtok_set_empty(pd->newauthtok); } if (pd->cmd == SSS_PAM_ACCT_MGMT) { SAFEALIGN_COPY_UINT32_CHECK(&len, buf + p, size, &p); if ((p + len ) > size) return EINVAL; pd->user = talloc_strndup(pd, (char *)(buf + p), len); if (pd->user == NULL) return ENOMEM; p += len; DEBUG(SSSDBG_CONF_SETTINGS, ("user: [%s]\n", pd->user)); } else { pd->user = NULL; } return EOK; } static int krb5_cleanup(struct krb5_req *kr) { if (kr == NULL) return EOK; if (kr->options != NULL) { sss_krb5_get_init_creds_opt_free(kr->ctx, kr->options); } if (kr->creds != NULL) { krb5_free_cred_contents(kr->ctx, kr->creds); krb5_free_creds(kr->ctx, kr->creds); } if (kr->name != NULL) sss_krb5_free_unparsed_name(kr->ctx, kr->name); if (kr->princ != NULL) krb5_free_principal(kr->ctx, kr->princ); if (kr->ctx != NULL) krb5_free_context(kr->ctx); memset(kr, 0, sizeof(struct krb5_req)); return EOK; } static krb5_error_code get_tgt_times(krb5_context ctx, const char *ccname, krb5_principal server_principal, krb5_principal client_principal, sss_krb5_ticket_times *tgtt) { krb5_error_code krberr; krb5_ccache ccache = NULL; krb5_creds mcred; krb5_creds cred; krberr = krb5_cc_resolve(ctx, ccname, &ccache); if (krberr != 0) { DEBUG(1, ("krb5_cc_resolve failed.\n")); goto done; } memset(&mcred, 0, sizeof(mcred)); memset(&cred, 0, sizeof(mcred)); mcred.server = server_principal; mcred.client = client_principal; krberr = krb5_cc_retrieve_cred(ctx, ccache, 0, &mcred, &cred); if (krberr != 0) { DEBUG(1, ("krb5_cc_retrieve_cred failed.\n")); krberr = 0; goto done; } tgtt->authtime = cred.times.authtime; tgtt->starttime = cred.times.starttime; tgtt->endtime = cred.times.endtime; tgtt->renew_till = cred.times.renew_till; krb5_free_cred_contents(ctx, &cred); krberr = 0; done: if (ccache != NULL) { krb5_cc_close(ctx, ccache); } return krberr; } static krb5_error_code check_fast_ccache(TALLOC_CTX *mem_ctx, krb5_context ctx, const char *primary, const char *realm, const char *keytab_name, char **fast_ccname) { TALLOC_CTX *tmp_ctx = NULL; krb5_error_code kerr; char *ccname; char *server_name; sss_krb5_ticket_times tgtt; krb5_keytab keytab = NULL; krb5_principal client_princ = NULL; krb5_principal server_princ = NULL; tmp_ctx = talloc_new(NULL); if (tmp_ctx == NULL) { DEBUG(1, ("talloc_new failed.\n")); return ENOMEM; } ccname = talloc_asprintf(tmp_ctx, "FILE:%s/fast_ccache_%s", DB_PATH, realm); if (ccname == NULL) { DEBUG(1, ("talloc_asprintf failed.\n")); kerr = ENOMEM; goto done; } if (keytab_name != NULL) { kerr = krb5_kt_resolve(ctx, keytab_name, &keytab); } else { kerr = krb5_kt_default(ctx, &keytab); } if (kerr) { DEBUG(SSSDBG_FATAL_FAILURE, ("Failed to read keytab file [%s]: %s\n", KEYTAB_CLEAN_NAME, sss_krb5_get_error_message(ctx, kerr))); goto done; } kerr = find_principal_in_keytab(ctx, keytab, primary, realm, &client_princ); if (kerr != 0) { DEBUG(SSSDBG_MINOR_FAILURE, ("find_principal_in_keytab failed for principal %s@%s.\n", primary, realm)); goto done; } server_name = talloc_asprintf(tmp_ctx, "krbtgt/%s@%s", realm, realm); if (server_name == NULL) { DEBUG(1, ("talloc_asprintf failed.\n")); kerr = ENOMEM; goto done; } kerr = krb5_parse_name(ctx, server_name, &server_princ); if (kerr != 0) { DEBUG(1, ("krb5_parse_name failed.\n")); goto done; } memset(&tgtt, 0, sizeof(tgtt)); kerr = get_tgt_times(ctx, ccname, server_princ, client_princ, &tgtt); if (kerr == 0) { if (tgtt.endtime > time(NULL)) { DEBUG(5, ("FAST TGT is still valid.\n")); goto done; } } kerr = get_and_save_tgt_with_keytab(ctx, client_princ, keytab, ccname); if (kerr != 0) { DEBUG(1, ("get_and_save_tgt_with_keytab failed.\n")); goto done; } kerr = 0; done: if (client_princ != NULL) { krb5_free_principal(ctx, client_princ); } if (server_princ != NULL) { krb5_free_principal(ctx, server_princ); } if (kerr == 0) { *fast_ccname = talloc_steal(mem_ctx, ccname); } talloc_free(tmp_ctx); if (keytab != NULL) { krb5_kt_close(ctx, keytab); } return kerr; } static errno_t k5c_recv_data(struct krb5_req *kr, int fd, uint32_t *offline) { uint8_t buf[IN_BUF_SIZE]; ssize_t len; errno_t ret; errno = 0; len = sss_atomic_read_s(fd, buf, IN_BUF_SIZE); if (len == -1) { ret = errno; ret = (ret == 0) ? EINVAL: ret; DEBUG(SSSDBG_CRIT_FAILURE, ("read failed [%d][%s].\n", ret, strerror(ret))); return ret; } ret = unpack_buffer(buf, len, kr, offline); if (ret != EOK) { DEBUG(1, ("unpack_buffer failed.\n")); } return ret; } static int k5c_setup_fast(struct krb5_req *kr, char *lifetime_str, bool demand) { krb5_principal fast_princ_struct; krb5_data *realm_data; char *fast_principal_realm; char *fast_principal; krb5_error_code kerr; char *tmp_str; DEBUG(SSSDBG_CONF_SETTINGS, ("%s is set to [%s]\n", SSSD_KRB5_LIFETIME, lifetime_str)); tmp_str = getenv(SSSD_KRB5_FAST_PRINCIPAL); if (tmp_str) { DEBUG(SSSDBG_CONF_SETTINGS, ("%s is set to [%s]\n", SSSD_KRB5_FAST_PRINCIPAL, tmp_str)); kerr = krb5_parse_name(kr->ctx, tmp_str, &fast_princ_struct); if (kerr) { DEBUG(1, ("krb5_parse_name failed.\n")); return kerr; } kerr = sss_krb5_unparse_name_flags(kr->ctx, fast_princ_struct, KRB5_PRINCIPAL_UNPARSE_NO_REALM, &tmp_str); if (kerr) { DEBUG(1, ("sss_krb5_unparse_name_flags failed.\n")); return kerr; } fast_principal = talloc_strdup(kr, tmp_str); if (!fast_principal) { DEBUG(1, ("talloc_strdup failed.\n")); return KRB5KRB_ERR_GENERIC; } free(tmp_str); realm_data = krb5_princ_realm(kr->ctx, fast_princ_struct); fast_principal_realm = talloc_asprintf(kr, "%.*s", realm_data->length, realm_data->data); if (!fast_principal_realm) { DEBUG(1, ("talloc_asprintf failed.\n")); return ENOMEM; } } else { fast_principal_realm = kr->realm; fast_principal = NULL; } kerr = check_fast_ccache(kr, kr->ctx, fast_principal, fast_principal_realm, kr->keytab, &kr->fast_ccname); if (kerr != 0) { DEBUG(1, ("check_fast_ccache failed.\n")); KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } kerr = sss_krb5_get_init_creds_opt_set_fast_ccache_name(kr->ctx, kr->options, kr->fast_ccname); if (kerr != 0) { DEBUG(1, ("sss_krb5_get_init_creds_opt_set_fast_ccache_name " "failed.\n")); KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } if (demand) { kerr = sss_krb5_get_init_creds_opt_set_fast_flags(kr->ctx, kr->options, SSS_KRB5_FAST_REQUIRED); if (kerr != 0) { DEBUG(1, ("sss_krb5_get_init_creds_opt_set_fast_flags " "failed.\n")); KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } } return EOK; } static int k5c_setup(struct krb5_req *kr, uint32_t offline) { krb5_error_code kerr; char *lifetime_str; char *use_fast_str; krb5_deltat lifetime; int parse_flags; kr->realm = getenv(SSSD_KRB5_REALM); if (kr->realm == NULL) { DEBUG(SSSDBG_MINOR_FAILURE, ("Cannot read [%s] from environment.\n", SSSD_KRB5_REALM)); } kerr = krb5_init_context(&kr->ctx); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } /* Set the global error context */ krb5_error_ctx = kr->ctx; if (debug_level & SSSDBG_TRACE_ALL) { kerr = sss_child_set_krb5_tracing(kr->ctx); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_MINOR_FAILURE, kerr); return EIO; } } /* Enterprise principals require that a default realm is available. To * make SSSD more robust in the case that the default realm option is * missing in krb5.conf or to allow SSSD to work with multiple unconnected * realms (e.g. AD domains without trust between them) the default realm * will be set explicitly. */ if (kr->use_enterprise_princ) { kerr = krb5_set_default_realm(kr->ctx, kr->realm); if (kerr != 0) { DEBUG(SSSDBG_CRIT_FAILURE, ("krb5_set_default_realm failed.\n")); } } parse_flags = kr->use_enterprise_princ ? KRB5_PRINCIPAL_PARSE_ENTERPRISE : 0; kerr = sss_krb5_parse_name_flags(kr->ctx, kr->upn, parse_flags, &kr->princ); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } kerr = krb5_unparse_name(kr->ctx, kr->princ, &kr->name); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } kr->creds = calloc(1, sizeof(krb5_creds)); if (kr->creds == NULL) { DEBUG(1, ("talloc_zero failed.\n")); return ENOMEM; } kerr = sss_krb5_get_init_creds_opt_alloc(kr->ctx, &kr->options); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } #ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_SET_RESPONDER kerr = krb5_get_init_creds_opt_set_responder(kr->ctx, kr->options, sss_krb5_responder, kr); if (kerr != 0) { KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } #endif #ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_SET_CHANGE_PASSWORD_PROMPT /* A prompter is used to catch messages about when a password will * expired. The library shall not use the prompter to ask for a new password * but shall return KRB5KDC_ERR_KEY_EXP. */ krb5_get_init_creds_opt_set_change_password_prompt(kr->options, 0); #endif lifetime_str = getenv(SSSD_KRB5_RENEWABLE_LIFETIME); if (lifetime_str == NULL) { DEBUG(SSSDBG_CONF_SETTINGS, ("Cannot read [%s] from environment.\n", SSSD_KRB5_RENEWABLE_LIFETIME)); } else { kerr = krb5_string_to_deltat(lifetime_str, &lifetime); if (kerr != 0) { DEBUG(1, ("krb5_string_to_deltat failed for [%s].\n", lifetime_str)); KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } DEBUG(SSSDBG_CONF_SETTINGS, ("%s is set to [%s]\n", SSSD_KRB5_RENEWABLE_LIFETIME, lifetime_str)); krb5_get_init_creds_opt_set_renew_life(kr->options, lifetime); } lifetime_str = getenv(SSSD_KRB5_LIFETIME); if (lifetime_str == NULL) { DEBUG(SSSDBG_CONF_SETTINGS, ("Cannot read [%s] from environment.\n", SSSD_KRB5_LIFETIME)); } else { kerr = krb5_string_to_deltat(lifetime_str, &lifetime); if (kerr != 0) { DEBUG(1, ("krb5_string_to_deltat failed for [%s].\n", lifetime_str)); KRB5_CHILD_DEBUG(SSSDBG_CRIT_FAILURE, kerr); return kerr; } DEBUG(SSSDBG_CONF_SETTINGS, ("%s is set to [%s]\n", SSSD_KRB5_LIFETIME, lifetime_str)); krb5_get_init_creds_opt_set_tkt_life(kr->options, lifetime); } if (!offline) { krb5_set_canonicalize(kr->options); use_fast_str = getenv(SSSD_KRB5_USE_FAST); if (use_fast_str == NULL || strcasecmp(use_fast_str, "never") == 0) { DEBUG(SSSDBG_CONF_SETTINGS, ("Not using FAST.\n")); } else if (strcasecmp(use_fast_str, "try") == 0) { kerr = k5c_setup_fast(kr, lifetime_str, false); } else if (strcasecmp(use_fast_str, "demand") == 0) { kerr = k5c_setup_fast(kr, lifetime_str, true); } else { DEBUG(SSSDBG_CRIT_FAILURE, ("Unsupported value [%s] for krb5_use_fast.\n", use_fast_str)); return EINVAL; } } /* TODO: set options, e.g. * krb5_get_init_creds_opt_set_forwardable * krb5_get_init_creds_opt_set_proxiable * krb5_get_init_creds_opt_set_etype_list * krb5_get_init_creds_opt_set_address_list * krb5_get_init_creds_opt_set_preauth_list * krb5_get_init_creds_opt_set_salt * krb5_get_init_creds_opt_set_change_password_prompt * krb5_get_init_creds_opt_set_pa */ return kerr; } int main(int argc, const char *argv[]) { struct krb5_req *kr = NULL; uint32_t offline; int opt; poptContext pc; int debug_fd = -1; errno_t ret; struct poptOption long_options[] = { POPT_AUTOHELP {"debug-level", 'd', POPT_ARG_INT, &debug_level, 0, _("Debug level"), NULL}, {"debug-timestamps", 0, POPT_ARG_INT, &debug_timestamps, 0, _("Add debug timestamps"), NULL}, {"debug-microseconds", 0, POPT_ARG_INT, &debug_microseconds, 0, _("Show timestamps with microseconds"), NULL}, {"debug-fd", 0, POPT_ARG_INT, &debug_fd, 0, _("An open file descriptor for the debug logs"), NULL}, POPT_TABLEEND }; /* Set debug level to invalid value so we can decide if -d 0 was used. */ debug_level = SSSDBG_INVALID; pc = poptGetContext(argv[0], argc, argv, long_options, 0); while((opt = poptGetNextOpt(pc)) != -1) { switch(opt) { default: fprintf(stderr, "\nInvalid option %s: %s\n\n", poptBadOption(pc, 0), poptStrerror(opt)); poptPrintUsage(pc, stderr, 0); _exit(-1); } } poptFreeContext(pc); DEBUG_INIT(debug_level); kr = talloc_zero(NULL, struct krb5_req); if (kr == NULL) { DEBUG(1, ("talloc failed.\n")); exit(-1); } debug_prg_name = talloc_asprintf(kr, "[sssd[krb5_child[%d]]]", getpid()); if (!debug_prg_name) { DEBUG(SSSDBG_CRIT_FAILURE, ("talloc_asprintf failed.\n")); ret = ENOMEM; goto done; } if (debug_fd != -1) { ret = set_debug_file_from_fd(debug_fd); if (ret != EOK) { DEBUG(SSSDBG_CRIT_FAILURE, ("set_debug_file_from_fd failed.\n")); } } DEBUG(SSSDBG_TRACE_FUNC, ("krb5_child started.\n")); ret = k5c_recv_data(kr, STDIN_FILENO, &offline); if (ret != EOK) { goto done; } close(STDIN_FILENO); ret = k5c_setup(kr, offline); if (ret != EOK) { DEBUG(SSSDBG_CRIT_FAILURE, ("krb5_child_setup failed.\n")); goto done; } switch(kr->pd->cmd) { case SSS_PAM_AUTHENTICATE: /* If we are offline, we need to create an empty ccache file */ if (offline) { DEBUG(SSSDBG_TRACE_FUNC, ("Will perform offline auth\n")); ret = create_empty_ccache(kr); } else { DEBUG(SSSDBG_TRACE_FUNC, ("Will perform online auth\n")); ret = tgt_req_child(kr); } break; case SSS_PAM_CHAUTHTOK: DEBUG(SSSDBG_TRACE_FUNC, ("Will perform password change\n")); ret = changepw_child(kr, false); break; case SSS_PAM_CHAUTHTOK_PRELIM: DEBUG(SSSDBG_TRACE_FUNC, ("Will perform password change checks\n")); ret = changepw_child(kr, true); break; case SSS_PAM_ACCT_MGMT: DEBUG(SSSDBG_TRACE_FUNC, ("Will perform account management\n")); ret = kuserok_child(kr); break; case SSS_CMD_RENEW: if (offline) { DEBUG(SSSDBG_CRIT_FAILURE, ("Cannot renew TGT while offline\n")); ret = KRB5_KDC_UNREACH; goto done; } DEBUG(SSSDBG_TRACE_FUNC, ("Will perform ticket renewal\n")); ret = renew_tgt_child(kr); break; default: DEBUG(1, ("PAM command [%d] not supported.\n", kr->pd->cmd)); ret = EINVAL; goto done; } ret = k5c_send_data(kr, STDOUT_FILENO, ret); if (ret != EOK) { DEBUG(SSSDBG_CRIT_FAILURE, ("Failed to send reply\n")); } done: krb5_cleanup(kr); talloc_free(kr); if (ret == EOK) { DEBUG(SSSDBG_TRACE_FUNC, ("krb5_child completed successfully\n")); exit(0); } else { DEBUG(SSSDBG_CRIT_FAILURE, ("krb5_child failed!\n")); exit(-1); } }