void kerberos_set_creds_enctype(krb5_creds *pcreds, int enctype)
{
#if defined(HAVE_KRB5_KEYBLOCK_IN_CREDS)
KRB5_KEY_TYPE((&pcreds->keyblock)) = enctype;
#elif defined(HAVE_KRB5_SESSION_IN_CREDS)
KRB5_KEY_TYPE((&pcreds->session)) = enctype;
#else
#error UNKNOWN_KEYBLOCK_MEMBER_IN_KRB5_CREDS_STRUCT
#endif
}
struct libnet_keytab_entry *libnet_keytab_search(struct libnet_keytab_context *ctx,
const char *principal,
int kvno,
const krb5_enctype enctype,
TALLOC_CTX *mem_ctx)
{
krb5_error_code ret = 0;
krb5_kt_cursor cursor;
krb5_keytab_entry kt_entry;
struct libnet_keytab_entry *entry = NULL;
ZERO_STRUCT(kt_entry);
ZERO_STRUCT(cursor);
ret = krb5_kt_start_seq_get(ctx->context, ctx->keytab, &cursor);
if (ret) {
DEBUG(10, ("krb5_kt_start_seq_get failed: %s\n",
error_message(ret)));
return NULL;
}
while (krb5_kt_next_entry(ctx->context, ctx->keytab, &kt_entry, &cursor) == 0)
{
krb5_keyblock *keyp;
char *princ_s = NULL;
entry = NULL;
if (kt_entry.vno != kvno) {
goto cont;
}
keyp = KRB5_KT_KEY(&kt_entry);
if (KRB5_KEY_TYPE(keyp) != enctype) {
goto cont;
}
entry = talloc_zero(mem_ctx, struct libnet_keytab_entry);
if (!entry) {
DEBUG(3, ("talloc failed\n"));
goto fail;
}
ret = smb_krb5_unparse_name(entry, ctx->context, kt_entry.principal,
&princ_s);
if (ret) {
goto cont;
}
if (strcmp(principal, princ_s) != 0) {
goto cont;
}
entry->principal = talloc_strdup(entry, princ_s);
if (!entry->principal) {
DEBUG(3, ("talloc_strdup_failed\n"));
goto fail;
}
entry->name = talloc_move(entry, &princ_s);
entry->password = data_blob_talloc(entry, KRB5_KEY_DATA(keyp),
KRB5_KEY_LENGTH(keyp));
if (!entry->password.data) {
DEBUG(3, ("data_blob_talloc failed\n"));
goto fail;
}
DEBUG(10, ("found entry\n"));
smb_krb5_kt_free_entry(ctx->context, &kt_entry);
break;
fail:
smb_krb5_kt_free_entry(ctx->context, &kt_entry);
TALLOC_FREE(entry);
break;
cont:
smb_krb5_kt_free_entry(ctx->context, &kt_entry);
TALLOC_FREE(entry);
continue;
}
krb5_kt_end_seq_get(ctx->context, ctx->keytab, &cursor);
return entry;
}
/**
* Remove all entries that have the given principal, kvno and enctype.
*/
static krb5_error_code libnet_keytab_remove_entries(krb5_context context,
krb5_keytab keytab,
const char *principal,
int kvno,
const krb5_enctype enctype,
bool ignore_kvno)
{
krb5_error_code ret;
krb5_kt_cursor cursor;
krb5_keytab_entry kt_entry;
ZERO_STRUCT(kt_entry);
ZERO_STRUCT(cursor);
ret = krb5_kt_start_seq_get(context, keytab, &cursor);
if (ret) {
return 0;
}
while (krb5_kt_next_entry(context, keytab, &kt_entry, &cursor) == 0)
{
krb5_keyblock *keyp;
char *princ_s = NULL;
if (kt_entry.vno != kvno && !ignore_kvno) {
goto cont;
}
keyp = KRB5_KT_KEY(&kt_entry);
if (KRB5_KEY_TYPE(keyp) != enctype) {
goto cont;
}
ret = smb_krb5_unparse_name(talloc_tos(), context, kt_entry.principal,
&princ_s);
if (ret) {
DEBUG(5, ("smb_krb5_unparse_name failed (%s)\n",
error_message(ret)));
goto cont;
}
if (strcmp(principal, princ_s) != 0) {
goto cont;
}
/* match found - remove */
DEBUG(10, ("found entry for principal %s, kvno %d, "
"enctype %d - trying to remove it\n",
princ_s, kt_entry.vno, KRB5_KEY_TYPE(keyp)));
ret = krb5_kt_end_seq_get(context, keytab, &cursor);
ZERO_STRUCT(cursor);
if (ret) {
DEBUG(5, ("krb5_kt_end_seq_get failed (%s)\n",
error_message(ret)));
goto cont;
}
ret = krb5_kt_remove_entry(context, keytab,
&kt_entry);
if (ret) {
DEBUG(5, ("krb5_kt_remove_entry failed (%s)\n",
error_message(ret)));
goto cont;
}
DEBUG(10, ("removed entry for principal %s, kvno %d, "
"enctype %d\n", princ_s, kt_entry.vno,
KRB5_KEY_TYPE(keyp)));
ret = krb5_kt_start_seq_get(context, keytab, &cursor);
if (ret) {
DEBUG(5, ("krb5_kt_start_seq_get failed (%s)\n",
error_message(ret)));
goto cont;
}
cont:
smb_krb5_kt_free_entry(context, &kt_entry);
TALLOC_FREE(princ_s);
}
ret = krb5_kt_end_seq_get(context, keytab, &cursor);
if (ret) {
DEBUG(5, ("krb5_kt_end_seq_get failed (%s)\n",
error_message(ret)));
}
return ret;
}
NTSTATUS gssapi_obtain_pac_blob(TALLOC_CTX *mem_ctx,
gss_ctx_id_t gssapi_context,
gss_name_t gss_client_name,
DATA_BLOB *pac_blob)
{
NTSTATUS status;
OM_uint32 gss_maj, gss_min;
#ifdef HAVE_GSS_GET_NAME_ATTRIBUTE
/*
* gss_get_name_attribute() in MIT krb5 1.10.0 can return unintialized pac_display_buffer
* and later gss_release_buffer() will crash on attempting to release it.
*
* So always initialize the buffer descriptors.
*
* See following links for more details:
* http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=658514
* http://krbdev.mit.edu/rt/Ticket/Display.html?user=guest&pass=guest&id=7087
*/
gss_buffer_desc pac_buffer = {
.value = NULL,
.length = 0
};
gss_buffer_desc pac_display_buffer = {
.value = NULL,
.length = 0
};
gss_buffer_desc pac_name = {
.value = discard_const("urn:mspac:"),
.length = sizeof("urn:mspac:")-1
};
int more = -1;
int authenticated = false;
int complete = false;
gss_maj = gss_get_name_attribute(
&gss_min, gss_client_name, &pac_name,
&authenticated, &complete,
&pac_buffer, &pac_display_buffer, &more);
if (gss_maj != 0) {
gss_OID oid = discard_const(gss_mech_krb5);
DBG_NOTICE("obtaining PAC via GSSAPI gss_get_name_attribute "
"failed: %s\n", gssapi_error_string(mem_ctx,
gss_maj, gss_min,
oid));
return NT_STATUS_ACCESS_DENIED;
} else if (authenticated && complete) {
/* The PAC blob is returned directly */
*pac_blob = data_blob_talloc(mem_ctx, pac_buffer.value,
pac_buffer.length);
if (!pac_blob->data) {
status = NT_STATUS_NO_MEMORY;
} else {
status = NT_STATUS_OK;
}
gss_maj = gss_release_buffer(&gss_min, &pac_buffer);
gss_maj = gss_release_buffer(&gss_min, &pac_display_buffer);
return status;
} else {
DEBUG(0, ("obtaining PAC via GSSAPI failed: authenticated: %s, complete: %s, more: %s\n",
authenticated ? "true" : "false",
complete ? "true" : "false",
more ? "true" : "false"));
return NT_STATUS_ACCESS_DENIED;
}
#elif defined(HAVE_GSS_INQUIRE_SEC_CONTEXT_BY_OID)
gss_OID_desc pac_data_oid = {
.elements = discard_const(EXTRACT_PAC_AUTHZ_DATA_FROM_SEC_CONTEXT_OID),
.length = EXTRACT_PAC_AUTHZ_DATA_FROM_SEC_CONTEXT_OID_LENGTH
};
gss_buffer_set_t set = GSS_C_NO_BUFFER_SET;
/* If we didn't have the routine to get a verified, validated
* PAC (supplied only by MIT at the time of writing), then try
* with the Heimdal OID (fetches the PAC directly and always
* validates) */
gss_maj = gss_inquire_sec_context_by_oid(
&gss_min, gssapi_context,
&pac_data_oid, &set);
/* First check for the error MIT gives for an unknown OID */
if (gss_maj == GSS_S_UNAVAILABLE) {
DEBUG(1, ("unable to obtain a PAC against this GSSAPI library. "
"GSSAPI secured connections are available only with Heimdal or MIT Kerberos >= 1.8\n"));
} else if (gss_maj != 0) {
DEBUG(2, ("obtaining PAC via GSSAPI gss_inqiure_sec_context_by_oid (Heimdal OID) failed: %s\n",
gssapi_error_string(mem_ctx, gss_maj, gss_min, gss_mech_krb5)));
} else {
if (set == GSS_C_NO_BUFFER_SET) {
DEBUG(0, ("gss_inquire_sec_context_by_oid returned unknown "
"data in results.\n"));
return NT_STATUS_INTERNAL_ERROR;
}
/* The PAC blob is returned directly */
*pac_blob = data_blob_talloc(mem_ctx, set->elements[0].value,
set->elements[0].length);
if (!pac_blob->data) {
status = NT_STATUS_NO_MEMORY;
} else {
status = NT_STATUS_OK;
}
gss_maj = gss_release_buffer_set(&gss_min, &set);
return status;
}
#else
DEBUG(1, ("unable to obtain a PAC against this GSSAPI library. "
"GSSAPI secured connections are available only with Heimdal or MIT Kerberos >= 1.8\n"));
#endif
return NT_STATUS_ACCESS_DENIED;
}
NTSTATUS gssapi_get_session_key(TALLOC_CTX *mem_ctx,
gss_ctx_id_t gssapi_context,
DATA_BLOB *session_key,
uint32_t *keytype)
{
OM_uint32 gss_min, gss_maj;
gss_buffer_set_t set = GSS_C_NO_BUFFER_SET;
gss_maj = gss_inquire_sec_context_by_oid(
&gss_min, gssapi_context,
&gse_sesskey_inq_oid, &set);
if (gss_maj) {
DEBUG(0, ("gss_inquire_sec_context_by_oid failed [%s]\n",
gssapi_error_string(mem_ctx,
gss_maj,
gss_min,
discard_const_p(struct gss_OID_desc_struct,
gss_mech_krb5))));
return NT_STATUS_NO_USER_SESSION_KEY;
}
if ((set == GSS_C_NO_BUFFER_SET) ||
(set->count == 0)) {
#ifdef HAVE_GSSKRB5_GET_SUBKEY
krb5_keyblock *subkey;
gss_maj = gsskrb5_get_subkey(&gss_min,
gssapi_context,
&subkey);
if (gss_maj != 0) {
DEBUG(1, ("NO session key for this mech\n"));
return NT_STATUS_NO_USER_SESSION_KEY;
}
if (session_key) {
*session_key = data_blob_talloc(mem_ctx,
KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
}
if (keytype) {
*keytype = KRB5_KEY_TYPE(subkey);
}
krb5_free_keyblock(NULL /* should be krb5_context */, subkey);
return NT_STATUS_OK;
#else
DEBUG(0, ("gss_inquire_sec_context_by_oid didn't return any session key (and no alternative method available)\n"));
return NT_STATUS_NO_USER_SESSION_KEY;
#endif
}
if (session_key) {
*session_key = data_blob_talloc(mem_ctx, set->elements[0].value,
set->elements[0].length);
}
if (keytype) {
int diflen, i;
const uint8_t *p;
*keytype = 0;
if (set->count < 2) {
#ifdef HAVE_GSSKRB5_GET_SUBKEY
krb5_keyblock *subkey;
gss_maj = gsskrb5_get_subkey(&gss_min,
gssapi_context,
&subkey);
if (gss_maj == 0) {
*keytype = KRB5_KEY_TYPE(subkey);
krb5_free_keyblock(NULL /* should be krb5_context */, subkey);
}
#endif
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_OK;
} else if (memcmp(set->elements[1].value,
gse_sesskeytype_oid.elements,
gse_sesskeytype_oid.length) != 0) {
/* Perhaps a non-krb5 session key */
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_OK;
}
p = (const uint8_t *)set->elements[1].value + gse_sesskeytype_oid.length;
diflen = set->elements[1].length - gse_sesskeytype_oid.length;
if (diflen <= 0) {
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_INVALID_PARAMETER;
}
for (i = 0; i < diflen; i++) {
*keytype = (*keytype << 7) | (p[i] & 0x7f);
if (i + 1 != diflen && (p[i] & 0x80) == 0) {
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_INVALID_PARAMETER;
}
}
}
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_OK;
}
char *gssapi_error_string(TALLOC_CTX *mem_ctx,
OM_uint32 maj_stat, OM_uint32 min_stat,
const gss_OID mech)
{
OM_uint32 disp_min_stat, disp_maj_stat;
gss_buffer_desc maj_error_message;
gss_buffer_desc min_error_message;
char *maj_error_string, *min_error_string;
OM_uint32 msg_ctx = 0;
char *ret;
maj_error_message.value = NULL;
min_error_message.value = NULL;
maj_error_message.length = 0;
min_error_message.length = 0;
disp_maj_stat = gss_display_status(&disp_min_stat, maj_stat,
GSS_C_GSS_CODE, mech,
&msg_ctx, &maj_error_message);
if (disp_maj_stat != 0) {
maj_error_message.value = NULL;
maj_error_message.length = 0;
}
disp_maj_stat = gss_display_status(&disp_min_stat, min_stat,
GSS_C_MECH_CODE, mech,
&msg_ctx, &min_error_message);
if (disp_maj_stat != 0) {
min_error_message.value = NULL;
min_error_message.length = 0;
}
maj_error_string = talloc_strndup(mem_ctx,
(char *)maj_error_message.value,
maj_error_message.length);
min_error_string = talloc_strndup(mem_ctx,
(char *)min_error_message.value,
min_error_message.length);
ret = talloc_asprintf(mem_ctx, "%s: %s",
maj_error_string, min_error_string);
talloc_free(maj_error_string);
talloc_free(min_error_string);
gss_release_buffer(&disp_min_stat, &maj_error_message);
gss_release_buffer(&disp_min_stat, &min_error_message);
return ret;
}
