diff options
Diffstat (limited to 'auth-krb4.c')
| -rw-r--r-- | auth-krb4.c | 368 |
1 files changed, 0 insertions, 368 deletions
diff --git a/auth-krb4.c b/auth-krb4.c deleted file mode 100644 index 9e1c800b..00000000 --- a/auth-krb4.c +++ /dev/null @@ -1,368 +0,0 @@ -/* - * Copyright (c) 1999 Dug Song. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR - * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. - * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, - * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT - * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF - * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -#include "includes.h" -RCSID("$OpenBSD: auth-krb4.c,v 1.30 2003/04/08 20:21:28 itojun Exp $"); - -#include "ssh.h" -#include "ssh1.h" -#include "packet.h" -#include "xmalloc.h" -#include "log.h" -#include "servconf.h" -#include "uidswap.h" -#include "auth.h" - -#ifdef AFS -#include "radix.h" -#endif - -#ifdef KRB4 -extern ServerOptions options; - -static int -krb4_init(void *context) -{ - static int cleanup_registered = 0; - Authctxt *authctxt = (Authctxt *)context; - const char *tkt_root = TKT_ROOT; - struct stat st; - int fd; - - if (!authctxt->krb4_ticket_file) { - /* Set unique ticket string manually since we're still root. */ - authctxt->krb4_ticket_file = xmalloc(MAXPATHLEN); -#ifdef AFS - if (lstat("/ticket", &st) != -1) - tkt_root = "/ticket/"; -#endif /* AFS */ - snprintf(authctxt->krb4_ticket_file, MAXPATHLEN, "%s%u_%ld", - tkt_root, authctxt->pw->pw_uid, (long)getpid()); - krb_set_tkt_string(authctxt->krb4_ticket_file); - } - /* Register ticket cleanup in case of fatal error. */ - if (!cleanup_registered) { - fatal_add_cleanup(krb4_cleanup_proc, authctxt); - cleanup_registered = 1; - } - /* Try to create our ticket file. */ - if ((fd = mkstemp(authctxt->krb4_ticket_file)) != -1) { - close(fd); - return (1); - } - /* Ticket file exists - make sure user owns it (just passed ticket). */ - if (lstat(authctxt->krb4_ticket_file, &st) != -1) { - if (st.st_mode == (S_IFREG | S_IRUSR | S_IWUSR) && - st.st_uid == authctxt->pw->pw_uid) - return (1); - } - /* Failure - cancel cleanup function, leaving ticket for inspection. */ - logit("WARNING: bad ticket file %s", authctxt->krb4_ticket_file); - - fatal_remove_cleanup(krb4_cleanup_proc, authctxt); - cleanup_registered = 0; - - xfree(authctxt->krb4_ticket_file); - authctxt->krb4_ticket_file = NULL; - - return (0); -} - -/* - * try krb4 authentication, - * return 1 on success, 0 on failure, -1 if krb4 is not available - */ -int -auth_krb4_password(Authctxt *authctxt, const char *password) -{ - AUTH_DAT adata; - KTEXT_ST tkt; - struct hostent *hp; - struct passwd *pw; - char localhost[MAXHOSTNAMELEN], phost[INST_SZ], realm[REALM_SZ]; - u_int32_t faddr; - int r; - - if ((pw = authctxt->pw) == NULL) - return (0); - - /* - * Try Kerberos password authentication only for non-root - * users and only if Kerberos is installed. - */ - if (pw->pw_uid != 0 && krb_get_lrealm(realm, 1) == KSUCCESS) { - /* Set up our ticket file. */ - if (!krb4_init(authctxt)) { - logit("Couldn't initialize Kerberos ticket file for %s!", - pw->pw_name); - goto failure; - } - /* Try to get TGT using our password. */ - r = krb_get_pw_in_tkt((char *) pw->pw_name, "", realm, - "krbtgt", realm, DEFAULT_TKT_LIFE, (char *)password); - if (r != INTK_OK) { - debug("Kerberos v4 password authentication for %s " - "failed: %s", pw->pw_name, krb_err_txt[r]); - goto failure; - } - /* Successful authentication. */ - chown(tkt_string(), pw->pw_uid, pw->pw_gid); - - /* - * Now that we have a TGT, try to get a local - * "rcmd" ticket to ensure that we are not talking - * to a bogus Kerberos server. - */ - gethostname(localhost, sizeof(localhost)); - strlcpy(phost, (char *)krb_get_phost(localhost), - sizeof(phost)); - r = krb_mk_req(&tkt, KRB4_SERVICE_NAME, phost, realm, 33); - - if (r == KSUCCESS) { - if ((hp = gethostbyname(localhost)) == NULL) { - logit("Couldn't get local host address!"); - goto failure; - } - memmove((void *)&faddr, (void *)hp->h_addr, - sizeof(faddr)); - - /* Verify our "rcmd" ticket. */ - r = krb_rd_req(&tkt, KRB4_SERVICE_NAME, phost, - faddr, &adata, ""); - if (r == RD_AP_UNDEC) { - /* - * Probably didn't have a srvtab on - * localhost. Disallow login. - */ - logit("Kerberos v4 TGT for %s unverifiable, " - "no srvtab installed? krb_rd_req: %s", - pw->pw_name, krb_err_txt[r]); - goto failure; - } else if (r != KSUCCESS) { - logit("Kerberos v4 %s ticket unverifiable: %s", - KRB4_SERVICE_NAME, krb_err_txt[r]); - goto failure; - } - } else if (r == KDC_PR_UNKNOWN) { - /* - * Disallow login if no rcmd service exists, and - * log the error. - */ - logit("Kerberos v4 TGT for %s unverifiable: %s; %s.%s " - "not registered, or srvtab is wrong?", pw->pw_name, - krb_err_txt[r], KRB4_SERVICE_NAME, phost); - goto failure; - } else { - /* - * TGT is bad, forget it. Possibly spoofed! - */ - debug("WARNING: Kerberos v4 TGT possibly spoofed " - "for %s: %s", pw->pw_name, krb_err_txt[r]); - goto failure; - } - /* Authentication succeeded. */ - return (1); - } else - /* Logging in as root or no local Kerberos realm. */ - debug("Unable to authenticate to Kerberos."); - - failure: - krb4_cleanup_proc(authctxt); - - if (!options.kerberos_or_local_passwd) - return (0); - - /* Fall back to ordinary passwd authentication. */ - return (-1); -} - -void -krb4_cleanup_proc(void *context) -{ - Authctxt *authctxt = (Authctxt *)context; - debug("krb4_cleanup_proc called"); - if (authctxt->krb4_ticket_file) { - (void) dest_tkt(); - xfree(authctxt->krb4_ticket_file); - authctxt->krb4_ticket_file = NULL; - } -} - -int -auth_krb4(Authctxt *authctxt, KTEXT auth, char **client, KTEXT reply) -{ - AUTH_DAT adat = {0}; - Key_schedule schedule; - struct sockaddr_in local, foreign; - char instance[INST_SZ]; - socklen_t slen; - u_int cksum; - int r, s; - - s = packet_get_connection_in(); - - slen = sizeof(local); - memset(&local, 0, sizeof(local)); - if (getsockname(s, (struct sockaddr *) & local, &slen) < 0) - debug("getsockname failed: %.100s", strerror(errno)); - slen = sizeof(foreign); - memset(&foreign, 0, sizeof(foreign)); - if (getpeername(s, (struct sockaddr *) & foreign, &slen) < 0) { - debug("getpeername failed: %.100s", strerror(errno)); - fatal_cleanup(); - } - instance[0] = '*'; - instance[1] = 0; - - /* Get the encrypted request, challenge, and session key. */ - if ((r = krb_rd_req(auth, KRB4_SERVICE_NAME, instance, - 0, &adat, ""))) { - debug("Kerberos v4 krb_rd_req: %.100s", krb_err_txt[r]); - return (0); - } - des_key_sched((des_cblock *) adat.session, schedule); - - *client = xmalloc(MAX_K_NAME_SZ); - (void) snprintf(*client, MAX_K_NAME_SZ, "%s%s%s@%s", adat.pname, - *adat.pinst ? "." : "", adat.pinst, adat.prealm); - - /* Check ~/.klogin authorization now. */ - if (kuserok(&adat, authctxt->user) != KSUCCESS) { - logit("Kerberos v4 .klogin authorization failed for %s to " - "account %s", *client, authctxt->user); - xfree(*client); - *client = NULL; - return (0); - } - /* Increment the checksum, and return it encrypted with the - session key. */ - cksum = adat.checksum + 1; - cksum = htonl(cksum); - - /* If we can't successfully encrypt the checksum, we send back an - empty message, admitting our failure. */ - if ((r = krb_mk_priv((u_char *) & cksum, reply->dat, sizeof(cksum) + 1, - schedule, &adat.session, &local, &foreign)) < 0) { - debug("Kerberos v4 mk_priv: (%d) %s", r, krb_err_txt[r]); - reply->dat[0] = 0; - reply->length = 0; - } else - reply->length = r; - - /* Clear session key. */ - memset(&adat.session, 0, sizeof(adat.session)); - return (1); -} -#endif /* KRB4 */ - -#ifdef AFS -int -auth_krb4_tgt(Authctxt *authctxt, const char *string) -{ - CREDENTIALS creds; - struct passwd *pw; - - if ((pw = authctxt->pw) == NULL) - goto failure; - - temporarily_use_uid(pw); - - if (!radix_to_creds(string, &creds)) { - logit("Protocol error decoding Kerberos v4 TGT"); - goto failure; - } - if (strncmp(creds.service, "", 1) == 0) /* backward compatibility */ - strlcpy(creds.service, "krbtgt", sizeof creds.service); - - if (strcmp(creds.service, "krbtgt")) { - logit("Kerberos v4 TGT (%s%s%s@%s) rejected for %s", - creds.pname, creds.pinst[0] ? "." : "", creds.pinst, - creds.realm, pw->pw_name); - goto failure; - } - if (!krb4_init(authctxt)) - goto failure; - - if (in_tkt(creds.pname, creds.pinst) != KSUCCESS) - goto failure; - - if (save_credentials(creds.service, creds.instance, creds.realm, - creds.session, creds.lifetime, creds.kvno, &creds.ticket_st, - creds.issue_date) != KSUCCESS) { - debug("Kerberos v4 TGT refused: couldn't save credentials"); - goto failure; - } - /* Successful authentication, passed all checks. */ - chown(tkt_string(), pw->pw_uid, pw->pw_gid); - - debug("Kerberos v4 TGT accepted (%s%s%s@%s)", - creds.pname, creds.pinst[0] ? "." : "", creds.pinst, creds.realm); - memset(&creds, 0, sizeof(creds)); - - restore_uid(); - - return (1); - - failure: - krb4_cleanup_proc(authctxt); - memset(&creds, 0, sizeof(creds)); - restore_uid(); - - return (0); -} - -int -auth_afs_token(Authctxt *authctxt, const char *token_string) -{ - CREDENTIALS creds; - struct passwd *pw; - uid_t uid; - - if ((pw = authctxt->pw) == NULL) - return (0); - - if (!radix_to_creds(token_string, &creds)) { - logit("Protocol error decoding AFS token"); - return (0); - } - if (strncmp(creds.service, "", 1) == 0) /* backward compatibility */ - strlcpy(creds.service, "afs", sizeof creds.service); - - if (strncmp(creds.pname, "AFS ID ", 7) == 0) - uid = atoi(creds.pname + 7); - else - uid = pw->pw_uid; - - if (kafs_settoken(creds.realm, uid, &creds)) { - logit("AFS token (%s@%s) rejected for %s", - creds.pname, creds.realm, pw->pw_name); - memset(&creds, 0, sizeof(creds)); - return (0); - } - debug("AFS token accepted (%s@%s)", creds.pname, creds.realm); - memset(&creds, 0, sizeof(creds)); - - return (1); -} -#endif /* AFS */ |