diff options
Diffstat (limited to 'crypto/openssh/auth-krb5.c')
| -rw-r--r-- | crypto/openssh/auth-krb5.c | 438 |
1 files changed, 230 insertions, 208 deletions
diff --git a/crypto/openssh/auth-krb5.c b/crypto/openssh/auth-krb5.c index efe9376..ff23c98 100644 --- a/crypto/openssh/auth-krb5.c +++ b/crypto/openssh/auth-krb5.c @@ -1,250 +1,272 @@ /* * Kerberos v5 authentication and ticket-passing routines. - * - * $FreeBSD$ */ #include "includes.h" +RCSID("$OpenBSD: auth-krb5.c,v 1.6 2002/03/04 17:27:39 stevesk Exp $"); +RCSID("$FreeBSD$"); + #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 KRB5 +#include <krb5.h> -krb5_context ssh_context = NULL; -krb5_auth_context auth_context; -krb5_ccache mem_ccache = NULL; /* Credential cache for acquired ticket */ +extern ServerOptions options; -/* Try krb5 authentication. server_user is passed for logging purposes only, - in auth is received ticket, in client is returned principal from the - ticket */ -int -auth_krb5(const char* server_user, krb5_data *auth, krb5_principal *client) +static int +krb5_init(void *context) { + Authctxt *authctxt = (Authctxt *)context; krb5_error_code problem; - krb5_principal server = NULL; - krb5_principal tkt_client = NULL; + static int cleanup_registered = 0; + + if (authctxt->krb5_ctx == NULL) { + problem = krb5_init_context(&authctxt->krb5_ctx); + if (problem) + return (problem); + krb5_init_ets(authctxt->krb5_ctx); + } + if (!cleanup_registered) { + fatal_add_cleanup(krb5_cleanup_proc, authctxt); + cleanup_registered = 1; + } + return (0); +} + +/* + * Try krb5 authentication. server_user is passed for logging purposes + * only, in auth is received ticket, in client is returned principal + * from the ticket + */ +int +auth_krb5(Authctxt *authctxt, krb5_data *auth, char **client) +{ + krb5_error_code problem; + krb5_principal server; krb5_data reply; - krb5_ticket *ticket = NULL; - int fd; - int ret; - + krb5_ticket *ticket; + int fd, ret; + + ret = 0; + server = NULL; + ticket = NULL; reply.length = 0; - - problem = krb5_init(); - if (problem) - return 0; - - problem = krb5_auth_con_init(ssh_context, &auth_context); - if (problem) { - log("Kerberos v5 authentication failed: %.100s", - krb5_get_err_text(ssh_context, problem)); - return 0; - } - - fd = packet_get_connection_in(); - problem = krb5_auth_con_setaddrs_from_fd(ssh_context, auth_context, &fd); - if (problem) { - ret = 0; - goto err; - } - - problem = krb5_sname_to_principal(ssh_context, NULL, NULL , + problem = krb5_init(authctxt); + if (problem) + goto err; + + problem = krb5_auth_con_init(authctxt->krb5_ctx, + &authctxt->krb5_auth_ctx); + if (problem) + goto err; + + fd = packet_get_connection_in(); + problem = krb5_auth_con_setaddrs_from_fd(authctxt->krb5_ctx, + authctxt->krb5_auth_ctx, &fd); + if (problem) + goto err; + + problem = krb5_sname_to_principal(authctxt->krb5_ctx, NULL, NULL , KRB5_NT_SRV_HST, &server); - if (problem) { - ret = 0; - goto err; - } - - problem = krb5_rd_req(ssh_context, &auth_context, auth, server, NULL, - NULL, &ticket); - if (problem) { - ret = 0; - goto err; - } - - problem = krb5_copy_principal(ssh_context, ticket->client, &tkt_client); - if (problem) { - ret = 0; - goto err; - } - + if (problem) + goto err; + + problem = krb5_rd_req(authctxt->krb5_ctx, &authctxt->krb5_auth_ctx, + auth, server, NULL, NULL, &ticket); + if (problem) + goto err; + + problem = krb5_copy_principal(authctxt->krb5_ctx, ticket->client, + &authctxt->krb5_user); + if (problem) + goto err; + /* if client wants mutual auth */ - problem = krb5_mk_rep(ssh_context, auth_context, &reply); - if (problem) { - ret = 0; - goto err; - } - - *client = tkt_client; - + problem = krb5_mk_rep(authctxt->krb5_ctx, authctxt->krb5_auth_ctx, + &reply); + if (problem) + goto err; + + /* Check .k5login authorization now. */ + if (!krb5_kuserok(authctxt->krb5_ctx, authctxt->krb5_user, + authctxt->pw->pw_name)) + goto err; + + if (client) + krb5_unparse_name(authctxt->krb5_ctx, authctxt->krb5_user, + client); + packet_start(SSH_SMSG_AUTH_KERBEROS_RESPONSE); packet_put_string((char *) reply.data, reply.length); packet_send(); packet_write_wait(); + ret = 1; - -err: + err: if (server) - krb5_free_principal(ssh_context, server); + krb5_free_principal(authctxt->krb5_ctx, server); if (ticket) - krb5_free_ticket(ssh_context, ticket); + krb5_free_ticket(authctxt->krb5_ctx, ticket); if (reply.length) - xfree(reply.data); - return ret; + xfree(reply.data); + + if (problem) { + if (authctxt->krb5_ctx != NULL) + debug("Kerberos v5 authentication failed: %s", + krb5_get_err_text(authctxt->krb5_ctx, problem)); + else + debug("Kerberos v5 authentication failed: %d", + problem); + } + + return (ret); } int -auth_krb5_tgt(char *server_user, krb5_data *tgt, krb5_principal tkt_client) +auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt) { - krb5_error_code problem; - krb5_ccache ccache = NULL; - - if (ssh_context == NULL) { - goto fail; - } - - problem = krb5_cc_gen_new(ssh_context, &krb5_mcc_ops, &ccache); - if (problem) { - goto fail; - } - - problem = krb5_cc_initialize(ssh_context, ccache, tkt_client); - if (problem) { - goto fail; - } - - problem = krb5_rd_cred2(ssh_context, auth_context, ccache, tgt); - if (problem) { - goto fail; - } - - mem_ccache = ccache; - ccache = NULL; - - /* - problem = krb5_cc_copy_cache(ssh_context, ccache, mem_ccache); - if (problem) { - mem_ccache = NULL; - goto fail; - } - - - problem = krb5_cc_destroy(ssh_context, ccache); - if (problem) - goto fail; - */ - -#if 0 - packet_start(SSH_SMSG_SUCCESS); - packet_send(); - packet_write_wait(); -#endif - return 1; - -fail: - if (ccache) - krb5_cc_destroy(ssh_context, ccache); -#if 0 - packet_start(SSH_SMSG_FAILURE); - packet_send(); - packet_write_wait(); -#endif - return 0; + krb5_error_code problem; + krb5_ccache ccache = NULL; + char *pname; + + if (authctxt->pw == NULL || authctxt->krb5_user == NULL) + return (0); + + temporarily_use_uid(authctxt->pw); + + problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_fcc_ops, &ccache); + if (problem) + goto fail; + + problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache, + authctxt->krb5_user); + if (problem) + goto fail; + + problem = krb5_rd_cred2(authctxt->krb5_ctx, authctxt->krb5_auth_ctx, + ccache, tgt); + if (problem) + goto fail; + + authctxt->krb5_fwd_ccache = ccache; + ccache = NULL; + + authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache); + + problem = krb5_unparse_name(authctxt->krb5_ctx, authctxt->krb5_user, + &pname); + if (problem) + goto fail; + + debug("Kerberos v5 TGT accepted (%s)", pname); + + restore_uid(); + + return (1); + + fail: + if (problem) + debug("Kerberos v5 TGT passing failed: %s", + krb5_get_err_text(authctxt->krb5_ctx, problem)); + if (ccache) + krb5_cc_destroy(authctxt->krb5_ctx, ccache); + + restore_uid(); + + return (0); } int -auth_krb5_password(struct passwd *pw, const char *password) +auth_krb5_password(Authctxt *authctxt, const char *password) { - krb5_error_code problem; - krb5_ccache ccache = NULL; - krb5_principal client = NULL; - int ret; - - problem = krb5_init(); - if (problem) - return 0; - - problem = krb5_parse_name(ssh_context, pw->pw_name, &client); - if (problem) { - ret = 0; - goto out; - } - - problem = krb5_cc_gen_new(ssh_context, &krb5_mcc_ops, &ccache); - if (problem) { - ret = 0; - goto out; - } - - problem = krb5_cc_initialize(ssh_context, ccache, client); - if (problem) { - ret = 0; - goto out; - } - - problem = krb5_verify_user(ssh_context, client, ccache, password, 1, NULL); - if (problem) { - ret = 0; - goto out; - } - -/* - problem = krb5_cc_copy_cache(ssh_context, ccache, mem_ccache); - if (problem) { - ret = 0; - mem_ccache = NULL; - goto out; - } - */ - mem_ccache = ccache; - ccache = NULL; - - ret = 1; -out: - if (client != NULL) - krb5_free_principal(ssh_context, client); - if (ccache != NULL) - krb5_cc_destroy(ssh_context, ccache); - return ret; + krb5_error_code problem; + + if (authctxt->pw == NULL) + return (0); + + temporarily_use_uid(authctxt->pw); + + problem = krb5_init(authctxt); + if (problem) + goto out; + + problem = krb5_parse_name(authctxt->krb5_ctx, authctxt->pw->pw_name, + &authctxt->krb5_user); + if (problem) + goto out; + + problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_mcc_ops, + &authctxt->krb5_fwd_ccache); + if (problem) + goto out; + + problem = krb5_cc_initialize(authctxt->krb5_ctx, + authctxt->krb5_fwd_ccache, authctxt->krb5_user); + if (problem) + goto out; + + restore_uid(); + problem = krb5_verify_user(authctxt->krb5_ctx, authctxt->krb5_user, + authctxt->krb5_fwd_ccache, password, 1, NULL); + temporarily_use_uid(authctxt->pw); + + if (problem) + goto out; + + authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache); + + out: + restore_uid(); + + if (problem) { + if (authctxt->krb5_ctx != NULL) + debug("Kerberos password authentication failed: %s", + krb5_get_err_text(authctxt->krb5_ctx, problem)); + else + debug("Kerberos password authentication failed: %d", + problem); + + krb5_cleanup_proc(authctxt); + + if (options.kerberos_or_local_passwd) + return (-1); + else + return (0); + } + return (1); } void -krb5_cleanup_proc(void *ignore) +krb5_cleanup_proc(void *context) { - extern krb5_principal tkt_client; - - debug("krb5_cleanup_proc() called"); - if (mem_ccache) - krb5_cc_destroy(ssh_context, mem_ccache); - if (tkt_client) - krb5_free_principal(ssh_context, tkt_client); - if (auth_context) - krb5_auth_con_free(ssh_context, auth_context); - if (ssh_context) - krb5_free_context(ssh_context); -} - -int -krb5_init(void) -{ - krb5_error_code problem; - static cleanup_registered = 0; - - if (ssh_context == NULL) { - problem = krb5_init_context(&ssh_context); - if (problem) - return problem; - krb5_init_ets(ssh_context); - } - - if (!cleanup_registered) { - fatal_add_cleanup(krb5_cleanup_proc, NULL); - cleanup_registered = 1; - } - return 0; + Authctxt *authctxt = (Authctxt *)context; + + debug("krb5_cleanup_proc called"); + if (authctxt->krb5_fwd_ccache) { + krb5_cc_destroy(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache); + authctxt->krb5_fwd_ccache = NULL; + } + if (authctxt->krb5_user) { + krb5_free_principal(authctxt->krb5_ctx, authctxt->krb5_user); + authctxt->krb5_user = NULL; + } + if (authctxt->krb5_auth_ctx) { + krb5_auth_con_free(authctxt->krb5_ctx, + authctxt->krb5_auth_ctx); + authctxt->krb5_auth_ctx = NULL; + } + if (authctxt->krb5_ctx) { + krb5_free_context(authctxt->krb5_ctx); + authctxt->krb5_ctx = NULL; + } } - + #endif /* KRB5 */ |
