move kerberos cache to /run/user/<uid>/ by default (#848228)

fix kerberos cache handling to allow sucessful ticket forwarding
This commit is contained in:
Petr Lautrbach 2013-06-17 17:29:55 +02:00
parent e6dbb83190
commit aacd017a6d

View File

@ -105,56 +105,79 @@ diff -up openssh-6.2p1/auth-krb5.c.gsskex openssh-6.2p1/auth-krb5.c
#include <krb5.h>
extern ServerOptions options;
@@ -170,8 +171,13 @@ auth_krb5_password(Authctxt *authctxt, c
@@ -77,6 +78,7 @@ auth_krb5_password(Authctxt *authctxt, c
#endif
krb5_error_code problem;
krb5_ccache ccache = NULL;
+ const char *ccache_type;
int len;
char *client, *platform_client;
len = strlen(authctxt->krb5_ticket_file) + 6;
@@ -166,12 +168,30 @@ auth_krb5_password(Authctxt *authctxt, c
goto out;
#endif
+ ccache_type = krb5_cc_get_type(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
- len = strlen(authctxt->krb5_ticket_file) + 6;
+ if (authctxt->krb5_ticket_file[0] == ':')
+ authctxt->krb5_ticket_file++;
+
+ len = strlen(authctxt->krb5_ticket_file) + strlen(ccache_type);
authctxt->krb5_ccname = xmalloc(len);
- snprintf(authctxt->krb5_ccname, len, "FILE:%s",
+
+#ifdef USE_CCAPI
+ snprintf(authctxt->krb5_ccname, len, "API:%s",
authctxt->krb5_ticket_file);
+#else
+ snprintf(authctxt->krb5_ccname, len, "DIR:%s",
+ authctxt->krb5_ticket_file);
+ snprintf(authctxt->krb5_ccname, len, "%s:%s",
+ ccache_type, authctxt->krb5_ticket_file);
+#endif
+
+ if (strcmp(ccache_type, "DIR") == 0) {
+ char *p;
+ p = strrchr(authctxt->krb5_ccname, '/');
+ if (p)
+ *p = '\0';
+ }
+
#ifdef USE_PAM
if (options.use_pam)
@@ -208,10 +214,33 @@ auth_krb5_password(Authctxt *authctxt, c
@@ -208,10 +228,30 @@ auth_krb5_password(Authctxt *authctxt, c
void
krb5_cleanup_proc(Authctxt *authctxt)
{
+ struct stat krb5_ccname_stat;
+ char krb5_ccname[128], *krb5_ccname_dir_end;
+ char krb5_ccname[128], *krb5_ccname_dir_start, *krb5_ccname_dir_end;
+
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;
+
+ /* assume ticket cache type DIR - DIR::/tmp/krb5cc_876600005_T9eDKSQvzb/tkt */
+ strncpy(krb5_ccname, authctxt->krb5_ccname + strlen("DIR::"), sizeof(krb5_ccname) - 10);
+ strncpy(krb5_ccname, authctxt->krb5_ccname, sizeof(krb5_ccname) - 10);
+ krb5_ccname_dir_start = strchr(krb5_ccname, ':') + 1;
+ strcat(krb5_ccname_dir_start, "/primary");
+
+ krb5_ccname_dir_end = strrchr(krb5_ccname, '/');
+ if (krb5_ccname_dir_end != NULL) {
+ strcpy(krb5_ccname_dir_end, "/primary");
+
+ if (stat(krb5_ccname, &krb5_ccname_stat) == 0) {
+ if (unlink(krb5_ccname) == 0) {
+ *krb5_ccname_dir_end = '\0';
+ if (rmdir(krb5_ccname) == -1)
+ debug("cache dir '%s' remove failed: %s", krb5_ccname, strerror(errno));
+ }
+ else
+ debug("cache primary file '%s', remove failed: %s",
+ krb5_ccname, strerror(errno)
+ );
+ if (stat(krb5_ccname_dir_start, &krb5_ccname_stat) == 0) {
+ if (unlink(krb5_ccname_dir_start) == 0) {
+ krb5_ccname_dir_end = strrchr(krb5_ccname_dir_start, '/');
+ *krb5_ccname_dir_end = '\0';
+ if (rmdir(krb5_ccname_dir_start) == -1)
+ debug("cache dir '%s' remove failed: %s", krb5_ccname_dir_start, strerror(errno));
+ }
+ else
+ debug("cache primary file '%s', remove failed: %s",
+ krb5_ccname_dir_start, strerror(errno)
+ );
+ }
}
if (authctxt->krb5_user) {
krb5_free_principal(authctxt->krb5_ctx, authctxt->krb5_user);
@@ -226,31 +255,37 @@ krb5_cleanup_proc(Authctxt *authctxt)
@@ -226,31 +266,45 @@ krb5_cleanup_proc(Authctxt *authctxt)
#ifndef HEIMDAL
krb5_error_code
ssh_krb5_cc_gen(krb5_context ctx, krb5_ccache *ccache) {
@ -162,17 +185,17 @@ diff -up openssh-6.2p1/auth-krb5.c.gsskex openssh-6.2p1/auth-krb5.c
- char ccname[40];
+ int ret, oerrno;
+ char ccname[128];
mode_t old_umask;
+#ifdef USE_CCAPI
+ char cctemplate[] = "API:krb5cc_%d";
+#else
+ char cctemplate[] = "DIR:/tmp/krb5cc_%d_XXXXXXXXXX";
mode_t old_umask;
+ char cctemplate[] = "DIR:/run/user/%d/krb5cc_XXXXXXXXXX";
+ char *tmpdir;
+#endif
ret = snprintf(ccname, sizeof(ccname),
- ret = snprintf(ccname, sizeof(ccname),
- "FILE:/tmp/krb5cc_%d_XXXXXXXXXX", geteuid());
+ cctemplate, geteuid());
+ ret = snprintf(ccname, sizeof(ccname), cctemplate, geteuid());
if (ret < 0 || (size_t)ret >= sizeof(ccname))
return ENOMEM;
@ -182,11 +205,20 @@ diff -up openssh-6.2p1/auth-krb5.c.gsskex openssh-6.2p1/auth-krb5.c
+ old_umask = umask(0077);
+ tmpdir = mkdtemp(ccname + strlen("DIR:"));
oerrno = errno;
+ if (tmpdir == NULL && errno == ENOENT) {
+ /* /run/user/uid doesn't exist -> fallback to /tmp */
+ ret = snprintf(ccname, sizeof(ccname), "DIR:/tmp/krb5cc_%d_XXXXXXXXXX", geteuid());
+ if (ret < 0 || (size_t)ret >= sizeof(ccname))
+ return ENOMEM;
+ tmpdir = mkdtemp(ccname + strlen("DIR:"));
+ oerrno = errno;
+ }
+
umask(old_umask);
- if (tmpfd == -1) {
- logit("mkstemp(): %.100s", strerror(oerrno));
+ if (tmpdir == NULL) {
+ logit("mkdtemp(): %.100s", strerror(oerrno));
+ logit("mkdtemp(): %s - %.100s", ccname, strerror(oerrno));
return oerrno;
}
@ -195,7 +227,7 @@ diff -up openssh-6.2p1/auth-krb5.c.gsskex openssh-6.2p1/auth-krb5.c
oerrno = errno;
- logit("fchmod(): %.100s", strerror(oerrno));
- close(tmpfd);
+ logit("chmod(): %.100s", strerror(oerrno));
+ logit("chmod(): %s - %.100s", ccname, strerror(oerrno));
return oerrno;
}
- close(tmpfd);
@ -934,7 +966,7 @@ diff -up openssh-6.2p1/gss-serv.c.gsskex openssh-6.2p1/gss-serv.c
gssapi_client.store.filename);
unlink(gssapi_client.store.filename);
+
+ /* Ticket cache: DIR::/tmp/krb5cc_876600005_T9eDKSQvzb/tkt */
+ /* Ticket cache: DIR::/run/user/13558/krb5cc_T9eDKSQvzb/tkt */
+ /* same code as in auth-krb5.c:krb5_cleanup_proc */
+ strncpy(krb5_ccname, gssapi_client.store.filename, sizeof(krb5_ccname) - 10);
+ krb5_ccname_dir_end = strrchr(krb5_ccname, '/');
@ -1087,19 +1119,21 @@ diff -up openssh-6.2p1/gss-serv-krb5.c.gsskex openssh-6.2p1/gss-serv-krb5.c
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -120,6 +120,7 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
@@ -119,7 +119,7 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
krb5_error_code problem;
krb5_principal princ;
OM_uint32 maj_status, min_status;
int len;
+ const char *new_ccname;
- int len;
+ const char *new_ccname, *new_cctype;
if (client->creds == NULL) {
debug("No credentials stored");
@@ -168,11 +169,18 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
@@ -168,11 +168,25 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
return;
}
- client->store.filename = xstrdup(krb5_cc_get_name(krb_context, ccache));
+ new_cctype = krb5_cc_get_type(krb_context, ccache);
+ new_ccname = krb5_cc_get_name(krb_context, ccache);
+
client->store.envvar = "KRB5CCNAME";
@ -1110,15 +1144,21 @@ diff -up openssh-6.2p1/gss-serv-krb5.c.gsskex openssh-6.2p1/gss-serv-krb5.c
+ xasprintf(&client->store.envval, "API:%s", new_ccname);
+ client->store.filename = NULL;
+#else
+ xasprintf(&client->store.envval, "DIR:%s", new_ccname);
+ if (new_ccname[0] == ':')
+ new_ccname++;
+ xasprintf(&client->store.envval, "%s:%s", new_cctype, new_ccname);
+ if (strcmp(new_cctype, "DIR") == 0) {
+ char *p;
+ p = strrchr(client->store.envval, '/');
+ if (p)
+ *p = '\0';
+ }
+ client->store.filename = xstrdup(new_ccname);
+#endif
#ifdef USE_PAM
if (options.use_pam)
@@ -184,6 +192,71 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
@@ -184,6 +198,71 @@ ssh_gssapi_krb5_storecreds(ssh_gssapi_cl
return;
}
@ -1190,7 +1230,7 @@ diff -up openssh-6.2p1/gss-serv-krb5.c.gsskex openssh-6.2p1/gss-serv-krb5.c
ssh_gssapi_mech gssapi_kerberos_mech = {
"toWM5Slw5Ew8Mqkay+al2g==",
"Kerberos",
@@ -191,7 +264,8 @@ ssh_gssapi_mech gssapi_kerberos_mech = {
@@ -191,7 +270,8 @@ ssh_gssapi_mech gssapi_kerberos_mech = {
NULL,
&ssh_gssapi_krb5_userok,
NULL,
@ -2273,7 +2313,7 @@ diff -up openssh-6.2p1/readconf.c.gsskex openssh-6.2p1/readconf.c
#endif
{ "fallbacktorsh", oDeprecated },
{ "usersh", oDeprecated },
@@ -483,10 +494,30 @@ parse_flag:
@@ -503,10 +514,30 @@ parse_flag:
intptr = &options->gss_authentication;
goto parse_flag;
@ -2304,7 +2344,7 @@ diff -up openssh-6.2p1/readconf.c.gsskex openssh-6.2p1/readconf.c
case oBatchMode:
intptr = &options->batch_mode;
goto parse_flag;
@@ -1139,7 +1170,12 @@ initialize_options(Options * options)
@@ -1158,7 +1189,12 @@ initialize_options(Options * options)
options->pubkey_authentication = -1;
options->challenge_response_authentication = -1;
options->gss_authentication = -1;
@ -2317,7 +2357,7 @@ diff -up openssh-6.2p1/readconf.c.gsskex openssh-6.2p1/readconf.c
options->password_authentication = -1;
options->kbd_interactive_authentication = -1;
options->kbd_interactive_devices = NULL;
@@ -1239,8 +1275,14 @@ fill_default_options(Options * options)
@@ -1258,8 +1294,14 @@ fill_default_options(Options * options)
options->challenge_response_authentication = 1;
if (options->gss_authentication == -1)
options->gss_authentication = 0;
@ -2806,7 +2846,36 @@ diff -up openssh-6.2p1/sshd.c.gsskex openssh-6.2p1/sshd.c
/*
* We don't want to listen forever unless the other side
* successfully authenticates itself. So we set up an alarm which is
@@ -2466,6 +2527,48 @@ do_ssh2_kex(void)
@@ -2139,14 +2200,6 @@ main(int ac, char **av)
#ifdef SSH_AUDIT_EVENTS
audit_event(SSH_AUTH_SUCCESS);
#endif
-
-#ifdef GSSAPI
- if (options.gss_authentication) {
- temporarily_use_uid(authctxt->pw);
- ssh_gssapi_storecreds();
- restore_uid();
- }
-#endif
#ifdef WITH_SELINUX
ssh_selinux_setup_exec_context(authctxt->pw->pw_name);
#endif
@@ -2156,6 +2209,13 @@ main(int ac, char **av)
do_pam_session();
}
#endif
+#ifdef GSSAPI
+ if (options.gss_authentication) {
+ temporarily_use_uid(authctxt->pw);
+ ssh_gssapi_storecreds();
+ restore_uid();
+ }
+#endif
/*
* In privilege separation, we fork another child and prepare
@@ -2466,6 +2526,48 @@ do_ssh2_kex(void)
myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = list_hostkey_types();
@ -2855,7 +2924,7 @@ diff -up openssh-6.2p1/sshd.c.gsskex openssh-6.2p1/sshd.c
/* start key exchange */
kex = kex_setup(myproposal);
kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
@@ -2473,6 +2576,13 @@ do_ssh2_kex(void)
@@ -2473,6 +2575,13 @@ do_ssh2_kex(void)
kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
kex->kex[KEX_ECDH_SHA2] = kexecdh_server;