rpms/gssproxy
5
0
Fork 0
Code Issues Pull Requests Releases Activity

Add flags filtering and flags enforcing.

Browse Source 
- resolves: https://fedorahosted.org/gss-proxy/ticket/109
This commit is contained in:
Günther Deschner 2013-11-20 15:33:27 +01:00
parent e2e2fe48c7
commit b4f5223d51
2 changed files with 426 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

420
gssproxy-0.3.0-flags_handling.patch Normal file
View File

@ -0,0 +1,420 @@
From 591fad86aba3520a76eaf75aa0fd5e585fac94a5 Mon Sep 17 00:00:00 2001
From: Simo Sorce <simo@redhat.com>
Date: Wed, 13 Nov 2013 19:54:27 -0500
Subject: [PATCH 1/5] Autoinitialize creds on init_sec_context
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
If the remote client tries to initialize the context without first
acquiring credentials, try to acquire appropriate credentials if
the service allows it.
Reviewed-by: Günther Deschner <gdeschner@redhat.com>
---
proxy/src/gp_rpc_init_sec_context.c | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)
diff --git a/proxy/src/gp_rpc_init_sec_context.c b/proxy/src/gp_rpc_init_sec_context.c
index 2781238..76ffaab 100644
--- a/proxy/src/gp_rpc_init_sec_context.c
+++ b/proxy/src/gp_rpc_init_sec_context.c
@@ -24,6 +24,7 @@
*/
#include "gp_rpc_process.h"
+#include <gssapi/gssapi_krb5.h>
int gp_init_sec_context(struct gp_call_ctx *gpcall,
union gp_rpc_arg *arg,
@@ -74,13 +75,7 @@ int gp_init_sec_context(struct gp_call_ctx *gpcall,
if (ret_maj) {
goto done;
}
- } else {
- /* FIXME: get ccache from gpsvc ? */
- ret_maj = GSS_S_CRED_UNAVAIL;
- ret_min = 0;
- goto done;
}
-
ret_maj = gp_conv_gssx_to_name(&ret_min, isca->target_name, &target_name);
if (ret_maj) {
goto done;
@@ -107,6 +102,23 @@ int gp_init_sec_context(struct gp_call_ctx *gpcall,
gp_conv_gssx_to_buffer(isca->input_token, &ibuf);
}
+ if (!isca->cred_handle) {
+ if (gss_oid_equal(mech_type, gss_mech_krb5)) {
+ ret_maj = gp_add_krb5_creds(&ret_min, gpcall,
+ NULL, NULL,
+ GSS_C_INITIATE,
+ time_req, 0, &ich,
+ NULL, NULL, NULL);
+ } else {
+ ret_maj = GSS_S_NO_CRED;
+ ret_min = 0;
+ }
+
+ if (ret_maj) {
+ goto done;
+ }
+ }
+
ret_maj = gss_init_sec_context(&ret_min,
ich,
&ctx,
@@ -170,5 +182,6 @@ done:
&iscr->status);
gss_release_name(&ret_min, &target_name);
gss_release_oid(&ret_min, &mech_type);
+ gss_release_cred(&ret_min, &ich);
return ret;
}
--
1.8.3.1
From 32b1d5aa0497c4e3677b4575cc7e299590df5618 Mon Sep 17 00:00:00 2001
From: Simo Sorce <simo@redhat.com>
Date: Wed, 13 Nov 2013 20:03:53 -0500
Subject: [PATCH 2/5] Try impersonation even when a name is not provided
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
In some cases a name may not be provided, still try to perform
impersonation if the service is configured that way.
Reviewed-by: Günther Deschner <gdeschner@redhat.com>
---
proxy/src/gp_creds.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/proxy/src/gp_creds.c b/proxy/src/gp_creds.c
index e02a667..5337390 100644
--- a/proxy/src/gp_creds.c
+++ b/proxy/src/gp_creds.c
@@ -289,6 +289,11 @@ static int gp_get_cred_environment(struct gp_call_ctx *gpcall,
}
*requested_name = name;
}
+ } else {
+ /* No name provided */
+ if (svc->euid != target_uid) {
+ user_requested = true;
+ }
}
/* impersonation case (only for initiation) */
--
1.8.3.1
From 6a096c0a0a37d2fa9e0b03edce05929a7d98f390 Mon Sep 17 00:00:00 2001
From: Simo Sorce <simo@redhat.com>
Date: Sat, 16 Nov 2013 17:01:24 -0500
Subject: [PATCH 3/5] config: Add code to source flag filters
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
2 New configuration options are made available:
- filter_flags
- enforce_flags
Any GSS Flags listed in the filter_flags option is forcibly filtered
out before a gss_init_sec_context() call is invoked.
Any GSS Flags listed in the enforce_flags option is forcibly added
to the list of flags requested by a gss_init_sec_context() call is
invoked.
Flags can be either literals or numeric and must be preceded by the
sign + (to add to the list) or - (to remove from the list).
Resolves: https://fedorahosted.org/gss-proxy/ticket/109
Reviewed-by: Günther Deschner <gdeschner@redhat.com>
---
proxy/src/gp_config.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++++++
proxy/src/gp_proxy.h | 2 ++
2 files changed, 90 insertions(+)
diff --git a/proxy/src/gp_config.c b/proxy/src/gp_config.c
index 8da291b..e21e70d 100644
--- a/proxy/src/gp_config.c
+++ b/proxy/src/gp_config.c
@@ -32,6 +32,27 @@
#include "gp_config.h"
#include "gp_selinux.h"
+#include <gssapi/gssapi.h>
+
+struct gp_flag_def {
+ const char *name;
+ uint32_t value;
+};
+
+struct gp_flag_def flag_names[] = {
+ { "DELEGATE", GSS_C_DELEG_FLAG },
+ { "MUTUAL_AUTH", GSS_C_MUTUAL_FLAG },
+ { "REPLAY_DETECT", GSS_C_REPLAY_FLAG },
+ { "SEQUENCE", GSS_C_SEQUENCE_FLAG },
+ { "CONFIDENTIALITY", GSS_C_CONF_FLAG },
+ { "INTEGRITIY", GSS_C_INTEG_FLAG },
+ { "ANONYMOUS", GSS_C_ANON_FLAG },
+ { NULL, 0 }
+};
+
+#define DEFAULT_FILTERED_FLAGS GSS_C_DELEG_FLAG
+#define DEFAULT_ENFORCED_FLAGS 0
+
static void free_str_array(const char ***a, int *count)
{
const char **array;
@@ -117,6 +138,60 @@ static int get_krb5_mech_cfg(struct gp_service *svc,
return ret;
}
+static int parse_flags(const char *value, uint32_t *storage)
+{
+ char *handle;
+ char *token;
+ char *str;
+ bool add;
+ unsigned long int conv;
+ uint32_t flagval;
+ int i;
+
+ str = strdup(value);
+ if (!str) {
+ return ENOMEM;
+ }
+
+ token = strtok_r(str, ", ", &handle);
+ for (token = strtok_r(str, ", ", &handle);
+ token != NULL;
+ token = strtok_r(NULL, ", ", &handle)) {
+ switch (token[0]) {
+ case '+':
+ add = true;
+ break;
+ case '-':
+ add = false;
+ break;
+ default:
+ GPERROR("Ignoring flag [%s], missing +/- qualifier.\n", token);
+ continue;
+ }
+ token++;
+ for (i = 0; flag_names[i].name != NULL; i++) {
+ if (strcasecmp(token, flag_names[i].name) == 0) {
+ flagval = flag_names[i].value;
+ break;
+ }
+ }
+ if (flag_names[i].name == NULL) {
+ conv = strtoul(token, &handle, 0);
+ if (conv == 0 || conv == ULONG_MAX || *handle != '\0') {
+ GPERROR("Ignoring flag [%s], unrecognized value.\n", token);
+ continue;
+ }
+ flagval = conv;
+ }
+ GPDEBUG("%s Flag %s (%u).\n", add?"Add":"Remove", token, flagval);
+ if (add) *storage |= flagval;
+ else *storage &= ~flagval;
+ }
+ safefree(str);
+
+ return 0;
+}
+
static int setup_service_creds_handle(struct gp_service *svc)
{
uint32_t ret_maj, ret_min;
@@ -297,6 +372,19 @@ static int load_services(struct gp_config *cfg, struct gp_ini_context *ctx)
goto done;
}
}
+
+ cfg->svcs[n]->filter_flags = DEFAULT_FILTERED_FLAGS;
+ ret = gp_config_get_string(ctx, secname, "filter_flags", &value);
+ if (ret == 0) {
+ parse_flags(value, &cfg->svcs[n]->filter_flags);
+ }
+
+ cfg->svcs[n]->enforce_flags = DEFAULT_ENFORCED_FLAGS;
+ ret = gp_config_get_string(ctx, secname, "enforce_flags", &value);
+ if (ret == 0) {
+ ret = parse_flags(value, &cfg->svcs[n]->enforce_flags);
+ if (ret) goto done;
+ }
}
safefree(secname);
}
diff --git a/proxy/src/gp_proxy.h b/proxy/src/gp_proxy.h
index 8390f5d..b6c64ae 100644
--- a/proxy/src/gp_proxy.h
+++ b/proxy/src/gp_proxy.h
@@ -57,6 +57,8 @@ struct gp_service {
char *socket;
SELINUX_CTX selinux_ctx;
gss_cred_usage_t cred_usage;
+ uint32_t filter_flags;
+ uint32_t enforce_flags;
uint32_t mechs;
struct gp_cred_krb5 krb5;
--
1.8.3.1
From 3df6ac81f4a6d8cf6ff514e7d7f2cbe58840c393 Mon Sep 17 00:00:00 2001
From: Simo Sorce <simo@redhat.com>
Date: Sat, 16 Nov 2013 17:09:45 -0500
Subject: [PATCH 4/5] server: Implement flag filtering enforcement
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Resolves: https://fedorahosted.org/gss-proxy/ticket/109
Reviewed-by: Günther Deschner <gdeschner@redhat.com>
---
proxy/src/gp_creds.c | 6 ++++++
proxy/src/gp_rpc_creds.h | 3 +++
proxy/src/gp_rpc_init_sec_context.c | 2 ++
3 files changed, 11 insertions(+)
diff --git a/proxy/src/gp_creds.c b/proxy/src/gp_creds.c
index 5337390..60c4e12 100644
--- a/proxy/src/gp_creds.c
+++ b/proxy/src/gp_creds.c
@@ -548,3 +548,9 @@ done:
return ret_maj;
}
+
+void gp_filter_flags(struct gp_call_ctx *gpcall, uint32_t *flags)
+{
+ *flags |= gpcall->service->enforce_flags;
+ *flags &= ~gpcall->service->filter_flags;
+}
diff --git a/proxy/src/gp_rpc_creds.h b/proxy/src/gp_rpc_creds.h
index 6389ebe..4c8febb 100644
--- a/proxy/src/gp_rpc_creds.h
+++ b/proxy/src/gp_rpc_creds.h
@@ -46,4 +46,7 @@ uint32_t gp_add_krb5_creds(uint32_t *min,
gss_OID_set *actual_mechs,
uint32_t *initiator_time_rec,
uint32_t *acceptor_time_rec);
+
+void gp_filter_flags(struct gp_call_ctx *gpcall, uint32_t *flags);
+
#endif /* _GP_RPC_CREDS_H_ */
diff --git a/proxy/src/gp_rpc_init_sec_context.c b/proxy/src/gp_rpc_init_sec_context.c
index 76ffaab..5e5d6f1 100644
--- a/proxy/src/gp_rpc_init_sec_context.c
+++ b/proxy/src/gp_rpc_init_sec_context.c
@@ -119,6 +119,8 @@ int gp_init_sec_context(struct gp_call_ctx *gpcall,
}
}
+ gp_filter_flags(gpcall, &req_flags);
+
ret_maj = gss_init_sec_context(&ret_min,
ich,
&ctx,
--
1.8.3.1
From c8386418a754211da5ddf5469a0f1c0fddf21240 Mon Sep 17 00:00:00 2001
From: Simo Sorce <simo@redhat.com>
Date: Sat, 16 Nov 2013 17:27:52 -0500
Subject: [PATCH 5/5] man: Describe new flag filtering/enforcing options
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Resolves: https://fedorahosted.org/gss-proxy/ticket/109
Reviewed-by: Günther Deschner <gdeschner@redhat.com>
---
proxy/man/gssproxy.conf.5.xml | 58 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 58 insertions(+)
diff --git a/proxy/man/gssproxy.conf.5.xml b/proxy/man/gssproxy.conf.5.xml
index b0012b5..b4d5add 100644
--- a/proxy/man/gssproxy.conf.5.xml
+++ b/proxy/man/gssproxy.conf.5.xml
@@ -162,6 +162,64 @@
</varlistentry>
<varlistentry>
+ <term>enforce_flags (string)</term>
+ <listitem>
+ <para>
+ A list of GSS Request Flags that are added
+ unconditionally to every context initialization
+ call.
+ Flags can only be added to the list or removed
+ from the list by prepending a +/- sign to the
+ flag name or value.
+ </para>
+ <para>
+ Recognized flag names: DELEGATE, MUTUAL_AUTH,
+ REPLAY_DETECT, SEQUENCE, CONFIDENTIALITY,
+ INTEGRITY, ANONYMOUS
+ </para>
+ <para>Examples:
+<programlisting>
+ <userinput moreinfo="none">enforce_flags = +REPLAY_DETECT</userinput>
+ <userinput moreinfo="none">enforce_flags = -0x0001</userinput>
+</programlisting>
+ </para>
+ <para>Default: enforce_flags =</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>filter_flags (string)</term>
+ <listitem>
+ <para>
+ A list of GSS Request Flags that are filtered
+ unconditionally from every context initialization
+ call.
+ Flags can only be added to the list or removed
+ from the list by prepending a +/- sign to the
+ flag name or value.
+ </para>
+ <para>
+ NOTE: Because often gssproxy is used to withold
+ access to credentials the Delegate Flag is filtered
+ by default. To allow a service to delegate
+ credentials use the first example below.
+ </para>
+ <para>
+ Recognized flag names: DELEGATE, MUTUAL_AUTH,
+ REPLAY_DETECT, SEQUENCE, CONFIDENTIALITY,
+ INTEGRITY, ANONYMOUS
+ </para>
+ <para>Examples:
+<programlisting>
+ <userinput moreinfo="none">filter_flags = -DELEGATE</userinput>
+ <userinput moreinfo="none">filter_flags = -0x0001 +ANONYMOUS</userinput>
+</programlisting>
+ </para>
+ <para>Default: filter_flags = +DELEGATE</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term>impersonate (boolean)</term>
<listitem>
<para>Use impersonation (s4u2self + s4u2proxy) to obtain credentials</para>
--
1.8.3.1

8
gssproxy.spec
View File

@ -1,6 +1,6 @@
Name: gssproxy
Version: 0.3.0
Release: 1%{?dist}
Release: 3%{?dist}
Summary: GSSAPI Proxy
Group: System Environment/Libraries
@ -11,6 +11,7 @@ BuildRoot: %(mktemp -ud %{_tmppath}/%{name}-%{version}-%{release}-XXXXXX)
Patch0: gssproxy-0.3.0-gss_init_sec_context.patch
Patch1: gssproxy-0.3.0-gss_inquire_cred_by_mech.patch
Patch2: gssproxy-0.3.0-continuations.patch
Patch3: gssproxy-0.3.0-flags_handling.patch
%global servicename gssproxy
%global pubconfpath %{_sysconfdir}/gssproxy
@ -58,6 +59,7 @@ A proxy for GSSAPI credential handling
%patch0 -p2 -b .gss_init_sec_context
%patch1 -p2 -b .gss_inquire_cred_by_mech
%patch2 -p2 -b .continuations
%patch3 -p2 -b .flags_handling
%build
autoreconf -f -i
@ -110,13 +112,15 @@ rm -rf %{buildroot}
%systemd_postun_with_restart gssproxy.service
%changelog
* Tue Nov 19 2013 Guenther Deschner <gdeschner@redhat.com> 0.3.0-1
* Tue Nov 19 2013 Guenther Deschner <gdeschner@redhat.com> 0.3.0-3
- Fix flags handling in gss_init_sec_context()
- resolves: https://fedorahosted.org/gss-proxy/ticket/106
- Fix OID handling in gss_inquire_cred_by_mech()
- resolves: https://fedorahosted.org/gss-proxy/ticket/107
- Fix continuation processing for not yet fully established contexts.
- resolves: https://fedorahosted.org/gss-proxy/ticket/108
- Add flags filtering and flags enforcing.
- resolves: https://fedorahosted.org/gss-proxy/ticket/109
* Wed Oct 23 2013 Guenther Deschner <gdeschner@redhat.com> 0.3.0-0
- New upstream release 0.3.0: