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-rw-r--r--app-crypt/mit-krb5/files/CVE-2015-2695.patch564
1 files changed, 564 insertions, 0 deletions
diff --git a/app-crypt/mit-krb5/files/CVE-2015-2695.patch b/app-crypt/mit-krb5/files/CVE-2015-2695.patch
new file mode 100644
index 00000000000..08bc8ab4bb5
--- /dev/null
+++ b/app-crypt/mit-krb5/files/CVE-2015-2695.patch
@@ -0,0 +1,564 @@
+From b51b33f2bc5d1497ddf5bd107f791c101695000d Mon Sep 17 00:00:00 2001
+From: Nicolas Williams <nico@twosigma.com>
+Date: Mon, 14 Sep 2015 12:27:52 -0400
+Subject: [PATCH] Fix SPNEGO context aliasing bugs [CVE-2015-2695]
+
+The SPNEGO mechanism currently replaces its context handle with the
+mechanism context handle upon establishment, under the assumption that
+most GSS functions are only called after context establishment. This
+assumption is incorrect, and can lead to aliasing violations for some
+programs. Maintain the SPNEGO context structure after context
+establishment and refer to it in all GSS methods. Add initiate and
+opened flags to the SPNEGO context structure for use in
+gss_inquire_context() prior to context establishment.
+
+CVE-2015-2695:
+
+In MIT krb5 1.5 and later, applications which call
+gss_inquire_context() on a partially-established SPNEGO context can
+cause the GSS-API library to read from a pointer using the wrong type,
+generally causing a process crash. This bug may go unnoticed, because
+the most common SPNEGO authentication scenario establishes the context
+after just one call to gss_accept_sec_context(). Java server
+applications using the native JGSS provider are vulnerable to this
+bug. A carefully crafted SPNEGO packet might allow the
+gss_inquire_context() call to succeed with attacker-determined
+results, but applications should not make access control decisions
+based on gss_inquire_context() results prior to context establishment.
+
+ CVSSv2 Vector: AV:N/AC:M/Au:N/C:N/I:N/A:C/E:POC/RL:OF/RC:C
+
+[ghudson@mit.edu: several bugfixes, style changes, and edge-case
+behavior changes; commit message and CVE description]
+
+ticket: 8244
+target_version: 1.14
+tags: pullup
+---
+ src/lib/gssapi/spnego/gssapiP_spnego.h | 2 +
+ src/lib/gssapi/spnego/spnego_mech.c | 254 ++++++++++++++++++++++++---------
+ 2 files changed, 192 insertions(+), 64 deletions(-)
+
+diff --git a/src/lib/gssapi/spnego/gssapiP_spnego.h b/src/lib/gssapi/spnego/gssapiP_spnego.h
+index 57372de..5c82764 100644
+--- a/src/lib/gssapi/spnego/gssapiP_spnego.h
++++ b/src/lib/gssapi/spnego/gssapiP_spnego.h
+@@ -103,6 +103,8 @@ typedef struct {
+ int firstpass;
+ int mech_complete;
+ int nego_done;
++ int initiate;
++ int opened;
+ OM_uint32 ctx_flags;
+ gss_name_t internal_name;
+ gss_OID actual_mech;
+diff --git a/src/lib/gssapi/spnego/spnego_mech.c b/src/lib/gssapi/spnego/spnego_mech.c
+index ef76e1f..7849c85 100644
+--- a/src/lib/gssapi/spnego/spnego_mech.c
++++ b/src/lib/gssapi/spnego/spnego_mech.c
+@@ -102,7 +102,7 @@ static OM_uint32 get_negotiable_mechs(OM_uint32 *, spnego_gss_cred_id_t,
+ gss_cred_usage_t, gss_OID_set *);
+ static void release_spnego_ctx(spnego_gss_ctx_id_t *);
+ static void check_spnego_options(spnego_gss_ctx_id_t);
+-static spnego_gss_ctx_id_t create_spnego_ctx(void);
++static spnego_gss_ctx_id_t create_spnego_ctx(int);
+ static int put_mech_set(gss_OID_set mechSet, gss_buffer_t buf);
+ static int put_input_token(unsigned char **, gss_buffer_t, unsigned int);
+ static int put_mech_oid(unsigned char **, gss_OID_const, unsigned int);
+@@ -454,7 +454,7 @@ check_spnego_options(spnego_gss_ctx_id_t spnego_ctx)
+ }
+
+ static spnego_gss_ctx_id_t
+-create_spnego_ctx(void)
++create_spnego_ctx(int initiate)
+ {
+ spnego_gss_ctx_id_t spnego_ctx = NULL;
+ spnego_ctx = (spnego_gss_ctx_id_t)
+@@ -477,6 +477,8 @@ create_spnego_ctx(void)
+ spnego_ctx->mic_rcvd = 0;
+ spnego_ctx->mech_complete = 0;
+ spnego_ctx->nego_done = 0;
++ spnego_ctx->opened = 0;
++ spnego_ctx->initiate = initiate;
+ spnego_ctx->internal_name = GSS_C_NO_NAME;
+ spnego_ctx->actual_mech = GSS_C_NO_OID;
+
+@@ -642,7 +644,7 @@ init_ctx_new(OM_uint32 *minor_status,
+ OM_uint32 ret;
+ spnego_gss_ctx_id_t sc = NULL;
+
+- sc = create_spnego_ctx();
++ sc = create_spnego_ctx(1);
+ if (sc == NULL)
+ return GSS_S_FAILURE;
+
+@@ -659,10 +661,7 @@ init_ctx_new(OM_uint32 *minor_status,
+ ret = GSS_S_FAILURE;
+ goto cleanup;
+ }
+- /*
+- * The actual context is not yet determined, set the output
+- * context handle to refer to the spnego context itself.
+- */
++
+ sc->ctx_handle = GSS_C_NO_CONTEXT;
+ *ctx = (gss_ctx_id_t)sc;
+ sc = NULL;
+@@ -1108,16 +1107,11 @@ spnego_gss_init_sec_context(
+ }
+ gss_release_buffer(&tmpmin, &mechtok_out);
+ if (ret == GSS_S_COMPLETE) {
+- /*
+- * Now, switch the output context to refer to the
+- * negotiated mechanism's context.
+- */
+- *context_handle = (gss_ctx_id_t)spnego_ctx->ctx_handle;
++ spnego_ctx->opened = 1;
+ if (actual_mech != NULL)
+ *actual_mech = spnego_ctx->actual_mech;
+ if (ret_flags != NULL)
+ *ret_flags = spnego_ctx->ctx_flags;
+- release_spnego_ctx(&spnego_ctx);
+ } else if (ret != GSS_S_CONTINUE_NEEDED) {
+ if (spnego_ctx != NULL) {
+ gss_delete_sec_context(&tmpmin,
+@@ -1285,7 +1279,7 @@ acc_ctx_hints(OM_uint32 *minor_status,
+ if (ret != GSS_S_COMPLETE)
+ goto cleanup;
+
+- sc = create_spnego_ctx();
++ sc = create_spnego_ctx(0);
+ if (sc == NULL) {
+ ret = GSS_S_FAILURE;
+ goto cleanup;
+@@ -1367,7 +1361,7 @@ acc_ctx_new(OM_uint32 *minor_status,
+ gss_release_buffer(&tmpmin, &sc->DER_mechTypes);
+ assert(mech_wanted != GSS_C_NO_OID);
+ } else
+- sc = create_spnego_ctx();
++ sc = create_spnego_ctx(0);
+ if (sc == NULL) {
+ ret = GSS_S_FAILURE;
+ *return_token = NO_TOKEN_SEND;
+@@ -1750,13 +1744,12 @@ spnego_gss_accept_sec_context(
+ ret = GSS_S_FAILURE;
+ }
+ if (ret == GSS_S_COMPLETE) {
+- *context_handle = (gss_ctx_id_t)sc->ctx_handle;
++ sc->opened = 1;
+ if (sc->internal_name != GSS_C_NO_NAME &&
+ src_name != NULL) {
+ *src_name = sc->internal_name;
+ sc->internal_name = GSS_C_NO_NAME;
+ }
+- release_spnego_ctx(&sc);
+ } else if (ret != GSS_S_CONTINUE_NEEDED) {
+ if (sc != NULL) {
+ gss_delete_sec_context(&tmpmin, &sc->ctx_handle,
+@@ -2069,8 +2062,13 @@ spnego_gss_unwrap(
+ gss_qop_t *qop_state)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_unwrap(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ input_message_buffer,
+ output_message_buffer,
+ conf_state,
+@@ -2090,8 +2088,13 @@ spnego_gss_wrap(
+ gss_buffer_t output_message_buffer)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_wrap(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ conf_req_flag,
+ qop_req,
+ input_message_buffer,
+@@ -2108,8 +2111,14 @@ spnego_gss_process_context_token(
+ const gss_buffer_t token_buffer)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ /* SPNEGO doesn't have its own context tokens. */
++ if (!sc->opened)
++ return (GSS_S_DEFECTIVE_TOKEN);
++
+ ret = gss_process_context_token(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ token_buffer);
+
+ return (ret);
+@@ -2133,19 +2142,9 @@ spnego_gss_delete_sec_context(
+ if (*ctx == NULL)
+ return (GSS_S_COMPLETE);
+
+- /*
+- * If this is still an SPNEGO mech, release it locally.
+- */
+- if ((*ctx)->magic_num == SPNEGO_MAGIC_ID) {
+- (void) gss_delete_sec_context(minor_status,
+- &(*ctx)->ctx_handle,
+- output_token);
+- (void) release_spnego_ctx(ctx);
+- } else {
+- ret = gss_delete_sec_context(minor_status,
+- context_handle,
+- output_token);
+- }
++ (void) gss_delete_sec_context(minor_status, &(*ctx)->ctx_handle,
++ output_token);
++ (void) release_spnego_ctx(ctx);
+
+ return (ret);
+ }
+@@ -2157,8 +2156,13 @@ spnego_gss_context_time(
+ OM_uint32 *time_rec)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_context_time(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ time_rec);
+ return (ret);
+ }
+@@ -2170,9 +2174,20 @@ spnego_gss_export_sec_context(
+ gss_buffer_t interprocess_token)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = *(spnego_gss_ctx_id_t *)context_handle;
++
++ /* We don't currently support exporting partially established
++ * contexts. */
++ if (!sc->opened)
++ return GSS_S_UNAVAILABLE;
++
+ ret = gss_export_sec_context(minor_status,
+- context_handle,
++ &sc->ctx_handle,
+ interprocess_token);
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT) {
++ release_spnego_ctx(&sc);
++ *context_handle = GSS_C_NO_CONTEXT;
++ }
+ return (ret);
+ }
+
+@@ -2182,11 +2197,12 @@ spnego_gss_import_sec_context(
+ const gss_buffer_t interprocess_token,
+ gss_ctx_id_t *context_handle)
+ {
+- OM_uint32 ret;
+- ret = gss_import_sec_context(minor_status,
+- interprocess_token,
+- context_handle);
+- return (ret);
++ /*
++ * Until we implement partial context exports, there are no SPNEGO
++ * exported context tokens, only tokens for underlying mechs. So just
++ * return an error for now.
++ */
++ return GSS_S_UNAVAILABLE;
+ }
+ #endif /* LEAN_CLIENT */
+
+@@ -2203,16 +2219,48 @@ spnego_gss_inquire_context(
+ int *opened)
+ {
+ OM_uint32 ret = GSS_S_COMPLETE;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (src_name != NULL)
++ *src_name = GSS_C_NO_NAME;
++ if (targ_name != NULL)
++ *targ_name = GSS_C_NO_NAME;
++ if (lifetime_rec != NULL)
++ *lifetime_rec = 0;
++ if (mech_type != NULL)
++ *mech_type = (gss_OID)gss_mech_spnego;
++ if (ctx_flags != NULL)
++ *ctx_flags = 0;
++ if (locally_initiated != NULL)
++ *locally_initiated = sc->initiate;
++ if (opened != NULL)
++ *opened = sc->opened;
++
++ if (sc->ctx_handle != GSS_C_NO_CONTEXT) {
++ ret = gss_inquire_context(minor_status, sc->ctx_handle,
++ src_name, targ_name, lifetime_rec,
++ mech_type, ctx_flags, NULL, NULL);
++ }
+
+- ret = gss_inquire_context(minor_status,
+- context_handle,
+- src_name,
+- targ_name,
+- lifetime_rec,
+- mech_type,
+- ctx_flags,
+- locally_initiated,
+- opened);
++ if (!sc->opened) {
++ /*
++ * We are still doing SPNEGO negotiation, so report SPNEGO as
++ * the OID. After negotiation is complete we will report the
++ * underlying mechanism OID.
++ */
++ if (mech_type != NULL)
++ *mech_type = (gss_OID)gss_mech_spnego;
++
++ /*
++ * Remove flags we don't support with partially-established
++ * contexts. (Change this to keep GSS_C_TRANS_FLAG if we add
++ * support for exporting partial SPNEGO contexts.)
++ */
++ if (ctx_flags != NULL) {
++ *ctx_flags &= ~GSS_C_PROT_READY_FLAG;
++ *ctx_flags &= ~GSS_C_TRANS_FLAG;
++ }
++ }
+
+ return (ret);
+ }
+@@ -2227,8 +2275,13 @@ spnego_gss_wrap_size_limit(
+ OM_uint32 *max_input_size)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_wrap_size_limit(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ conf_req_flag,
+ qop_req,
+ req_output_size,
+@@ -2245,8 +2298,13 @@ spnego_gss_get_mic(
+ gss_buffer_t message_token)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_get_mic(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ qop_req,
+ message_buffer,
+ message_token);
+@@ -2262,8 +2320,13 @@ spnego_gss_verify_mic(
+ gss_qop_t *qop_state)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_verify_mic(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ msg_buffer,
+ token_buffer,
+ qop_state);
+@@ -2278,8 +2341,14 @@ spnego_gss_inquire_sec_context_by_oid(
+ gss_buffer_set_t *data_set)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ /* There are no SPNEGO-specific OIDs for this function. */
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_UNAVAILABLE);
++
+ ret = gss_inquire_sec_context_by_oid(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ desired_object,
+ data_set);
+ return (ret);
+@@ -2359,8 +2428,15 @@ spnego_gss_set_sec_context_option(
+ const gss_buffer_t value)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)*context_handle;
++
++ /* There are no SPNEGO-specific OIDs for this function, and we cannot
++ * construct an empty SPNEGO context with it. */
++ if (sc == NULL || sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_UNAVAILABLE);
++
+ ret = gss_set_sec_context_option(minor_status,
+- context_handle,
++ &sc->ctx_handle,
+ desired_object,
+ value);
+ return (ret);
+@@ -2377,8 +2453,13 @@ spnego_gss_wrap_aead(OM_uint32 *minor_status,
+ gss_buffer_t output_message_buffer)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_wrap_aead(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ conf_req_flag,
+ qop_req,
+ input_assoc_buffer,
+@@ -2399,8 +2480,13 @@ spnego_gss_unwrap_aead(OM_uint32 *minor_status,
+ gss_qop_t *qop_state)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_unwrap_aead(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ input_message_buffer,
+ input_assoc_buffer,
+ output_payload_buffer,
+@@ -2419,8 +2505,13 @@ spnego_gss_wrap_iov(OM_uint32 *minor_status,
+ int iov_count)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_wrap_iov(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ conf_req_flag,
+ qop_req,
+ conf_state,
+@@ -2438,8 +2529,13 @@ spnego_gss_unwrap_iov(OM_uint32 *minor_status,
+ int iov_count)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_unwrap_iov(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ conf_state,
+ qop_state,
+ iov,
+@@ -2457,8 +2553,13 @@ spnego_gss_wrap_iov_length(OM_uint32 *minor_status,
+ int iov_count)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_wrap_iov_length(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ conf_req_flag,
+ qop_req,
+ conf_state,
+@@ -2475,8 +2576,13 @@ spnego_gss_complete_auth_token(
+ gss_buffer_t input_message_buffer)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_UNAVAILABLE);
++
+ ret = gss_complete_auth_token(minor_status,
+- context_handle,
++ sc->ctx_handle,
+ input_message_buffer);
+ return (ret);
+ }
+@@ -2721,8 +2827,13 @@ spnego_gss_pseudo_random(OM_uint32 *minor_status,
+ gss_buffer_t prf_out)
+ {
+ OM_uint32 ret;
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
+ ret = gss_pseudo_random(minor_status,
+- context,
++ sc->ctx_handle,
+ prf_key,
+ prf_in,
+ desired_output_len,
+@@ -2863,7 +2974,12 @@ spnego_gss_get_mic_iov(OM_uint32 *minor_status, gss_ctx_id_t context_handle,
+ gss_qop_t qop_req, gss_iov_buffer_desc *iov,
+ int iov_count)
+ {
+- return gss_get_mic_iov(minor_status, context_handle, qop_req, iov,
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
++ return gss_get_mic_iov(minor_status, sc->ctx_handle, qop_req, iov,
+ iov_count);
+ }
+
+@@ -2872,7 +2988,12 @@ spnego_gss_verify_mic_iov(OM_uint32 *minor_status, gss_ctx_id_t context_handle,
+ gss_qop_t *qop_state, gss_iov_buffer_desc *iov,
+ int iov_count)
+ {
+- return gss_verify_mic_iov(minor_status, context_handle, qop_state, iov,
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
++ return gss_verify_mic_iov(minor_status, sc->ctx_handle, qop_state, iov,
+ iov_count);
+ }
+
+@@ -2881,7 +3002,12 @@ spnego_gss_get_mic_iov_length(OM_uint32 *minor_status,
+ gss_ctx_id_t context_handle, gss_qop_t qop_req,
+ gss_iov_buffer_desc *iov, int iov_count)
+ {
+- return gss_get_mic_iov_length(minor_status, context_handle, qop_req, iov,
++ spnego_gss_ctx_id_t sc = (spnego_gss_ctx_id_t)context_handle;
++
++ if (sc->ctx_handle == GSS_C_NO_CONTEXT)
++ return (GSS_S_NO_CONTEXT);
++
++ return gss_get_mic_iov_length(minor_status, sc->ctx_handle, qop_req, iov,
+ iov_count);
+ }
+