crypto/x509/x509_trust.c - third_party/openssl - Git at Google

 /*
  * Copyright 1999-2021 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the Apache License 2.0 (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
  * in the file LICENSE in the source distribution or at
  * https://www.openssl.org/source/license.html
  */

 #include <stdio.h>
 #include "internal/cryptlib.h"
 #include <openssl/x509v3.h>
 #include "crypto/x509.h"

 static int tr_cmp(const X509_TRUST *const *a, const X509_TRUST *const *b);
 static void trtable_free(X509_TRUST *p);

 static int trust_1oidany(X509_TRUST *trust, X509 *x, int flags);
 static int trust_1oid(X509_TRUST *trust, X509 *x, int flags);
 static int trust_compat(X509_TRUST *trust, X509 *x, int flags);

 static int obj_trust(int id, X509 *x, int flags);
 static int (*default_trust) (int id, X509 *x, int flags) = obj_trust;

 /*
  * WARNING: the following table should be kept in order of trust and without
  * any gaps so we can just subtract the minimum trust value to get an index
  * into the table
  */

 static X509_TRUST trstandard[] = {
     {X509_TRUST_COMPAT, 0, trust_compat, "compatible", 0, NULL},
     {X509_TRUST_SSL_CLIENT, 0, trust_1oidany, "SSL Client", NID_client_auth,
      NULL},
     {X509_TRUST_SSL_SERVER, 0, trust_1oidany, "SSL Server", NID_server_auth,
      NULL},
     {X509_TRUST_EMAIL, 0, trust_1oidany, "S/MIME email", NID_email_protect,
      NULL},
     {X509_TRUST_OBJECT_SIGN, 0, trust_1oidany, "Object Signer", NID_code_sign,
      NULL},
     {X509_TRUST_OCSP_SIGN, 0, trust_1oid, "OCSP responder", NID_OCSP_sign,
      NULL},
     {X509_TRUST_OCSP_REQUEST, 0, trust_1oid, "OCSP request", NID_ad_OCSP,
      NULL},
     {X509_TRUST_TSA, 0, trust_1oidany, "TSA server", NID_time_stamp, NULL}
 };

 #define X509_TRUST_COUNT        OSSL_NELEM(trstandard)

 static STACK_OF(X509_TRUST) *trtable = NULL;

 static int tr_cmp(const X509_TRUST *const *a, const X509_TRUST *const *b)
 {
     return (*a)->trust - (*b)->trust;
 }

 int (*X509_TRUST_set_default(int (*trust) (int, X509 *, int))) (int, X509 *,
                                                                 int) {
     int (*oldtrust) (int, X509 *, int);
     oldtrust = default_trust;
     default_trust = trust;
     return oldtrust;
 }

 int X509_check_trust(X509 *x, int id, int flags)
 {
     X509_TRUST *pt;
     int idx;

     /* We get this as a default value */
     if (id == X509_TRUST_DEFAULT)
         return obj_trust(NID_anyExtendedKeyUsage, x,
                          flags | X509_TRUST_DO_SS_COMPAT);
     idx = X509_TRUST_get_by_id(id);
     if (idx < 0)
         return default_trust(id, x, flags);
     pt = X509_TRUST_get0(idx);
     return pt->check_trust(pt, x, flags);
 }

 int X509_TRUST_get_count(void)
 {
     if (!trtable)
         return X509_TRUST_COUNT;
     return sk_X509_TRUST_num(trtable) + X509_TRUST_COUNT;
 }

 X509_TRUST *X509_TRUST_get0(int idx)
 {
     if (idx < 0)
         return NULL;
     if (idx < (int)X509_TRUST_COUNT)
         return trstandard + idx;
     return sk_X509_TRUST_value(trtable, idx - X509_TRUST_COUNT);
 }

 int X509_TRUST_get_by_id(int id)
 {
     X509_TRUST tmp;
     int idx;

     if ((id >= X509_TRUST_MIN) && (id <= X509_TRUST_MAX))
         return id - X509_TRUST_MIN;
     if (trtable == NULL)
         return -1;
     tmp.trust = id;
     idx = sk_X509_TRUST_find(trtable, &tmp);
     if (idx < 0)
         return -1;
     return idx + X509_TRUST_COUNT;
 }

 int X509_TRUST_set(int *t, int trust)
 {
     if (X509_TRUST_get_by_id(trust) < 0) {
         ERR_raise(ERR_LIB_X509, X509_R_INVALID_TRUST);
         return 0;
     }
     *t = trust;
     return 1;
 }

 int X509_TRUST_add(int id, int flags, int (*ck) (X509_TRUST *, X509 *, int),
                    const char *name, int arg1, void *arg2)
 {
     int idx;
     X509_TRUST *trtmp;
     /*
      * This is set according to what we change: application can't set it
      */
     flags &= ~X509_TRUST_DYNAMIC;
     /* This will always be set for application modified trust entries */
     flags |= X509_TRUST_DYNAMIC_NAME;
     /* Get existing entry if any */
     idx = X509_TRUST_get_by_id(id);
     /* Need a new entry */
     if (idx < 0) {
         if ((trtmp = OPENSSL_malloc(sizeof(*trtmp))) == NULL) {
             ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
             return 0;
         }
         trtmp->flags = X509_TRUST_DYNAMIC;
     } else
         trtmp = X509_TRUST_get0(idx);

     /* OPENSSL_free existing name if dynamic */
     if (trtmp->flags & X509_TRUST_DYNAMIC_NAME)
         OPENSSL_free(trtmp->name);
     /* dup supplied name */
     if ((trtmp->name = OPENSSL_strdup(name)) == NULL) {
         ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
         goto err;
     }
     /* Keep the dynamic flag of existing entry */
     trtmp->flags &= X509_TRUST_DYNAMIC;
     /* Set all other flags */
     trtmp->flags |= flags;

     trtmp->trust = id;
     trtmp->check_trust = ck;
     trtmp->arg1 = arg1;
     trtmp->arg2 = arg2;

     /* If its a new entry manage the dynamic table */
     if (idx < 0) {
         if (trtable == NULL
             && (trtable = sk_X509_TRUST_new(tr_cmp)) == NULL) {
             ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
             goto err;
         }
         if (!sk_X509_TRUST_push(trtable, trtmp)) {
             ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
             goto err;
         }
     }
     return 1;
  err:
     if (idx < 0) {
         OPENSSL_free(trtmp->name);
         OPENSSL_free(trtmp);
     }
     return 0;
 }

 static void trtable_free(X509_TRUST *p)
 {
     if (p == NULL)
         return;
     if (p->flags & X509_TRUST_DYNAMIC) {
         if (p->flags & X509_TRUST_DYNAMIC_NAME)
             OPENSSL_free(p->name);
         OPENSSL_free(p);
     }
 }

 void X509_TRUST_cleanup(void)
 {
     sk_X509_TRUST_pop_free(trtable, trtable_free);
     trtable = NULL;
 }

 int X509_TRUST_get_flags(const X509_TRUST *xp)
 {
     return xp->flags;
 }

 char *X509_TRUST_get0_name(const X509_TRUST *xp)
 {
     return xp->name;
 }

 int X509_TRUST_get_trust(const X509_TRUST *xp)
 {
     return xp->trust;
 }

 static int trust_1oidany(X509_TRUST *trust, X509 *x, int flags)
 {
     /*
      * Declare the chain verified if the desired trust OID is not rejected in
      * any auxiliary trust info for this certificate, and the OID is either
      * expressly trusted, or else either "anyEKU" is trusted, or the
      * certificate is self-signed and X509_TRUST_NO_SS_COMPAT is not set.
      */
     flags |= X509_TRUST_DO_SS_COMPAT | X509_TRUST_OK_ANY_EKU;
     return obj_trust(trust->arg1, x, flags);
 }

 static int trust_1oid(X509_TRUST *trust, X509 *x, int flags)
 {
     /*
      * Declare the chain verified only if the desired trust OID is not
      * rejected and is expressly trusted.  Neither "anyEKU" nor "compat"
      * trust in self-signed certificates apply.
      */
     flags &= ~(X509_TRUST_DO_SS_COMPAT | X509_TRUST_OK_ANY_EKU);
     return obj_trust(trust->arg1, x, flags);
 }

 static int trust_compat(X509_TRUST *trust, X509 *x, int flags)
 {
     /* Call for side-effect of setting EXFLAG_SS for self-signed-certs */
     if (X509_check_purpose(x, -1, 0) != 1)
         return X509_TRUST_UNTRUSTED;
     if ((flags & X509_TRUST_NO_SS_COMPAT) == 0 && (x->ex_flags & EXFLAG_SS))
         return X509_TRUST_TRUSTED;
     else
         return X509_TRUST_UNTRUSTED;
 }

 static int obj_trust(int id, X509 *x, int flags)
 {
     X509_CERT_AUX *ax = x->aux;
     int i;

     if (ax && ax->reject) {
         for (i = 0; i < sk_ASN1_OBJECT_num(ax->reject); i++) {
             ASN1_OBJECT *obj = sk_ASN1_OBJECT_value(ax->reject, i);
             int nid = OBJ_obj2nid(obj);

             if (nid == id || (nid == NID_anyExtendedKeyUsage &&
                 (flags & X509_TRUST_OK_ANY_EKU)))
                 return X509_TRUST_REJECTED;
         }
     }

     if (ax && ax->trust) {
         for (i = 0; i < sk_ASN1_OBJECT_num(ax->trust); i++) {
             ASN1_OBJECT *obj = sk_ASN1_OBJECT_value(ax->trust, i);
             int nid = OBJ_obj2nid(obj);

             if (nid == id || (nid == NID_anyExtendedKeyUsage &&
                 (flags & X509_TRUST_OK_ANY_EKU)))
                 return X509_TRUST_TRUSTED;
         }
         /*
          * Reject when explicit trust EKU are set and none match.
          *
          * Returning untrusted is enough for for full chains that end in
          * self-signed roots, because when explicit trust is specified it
          * suppresses the default blanket trust of self-signed objects.
          *
          * But for partial chains, this is not enough, because absent a similar
          * trust-self-signed policy, non matching EKUs are indistinguishable
          * from lack of EKU constraints.
          *
          * Therefore, failure to match any trusted purpose must trigger an
          * explicit reject.
          */
         return X509_TRUST_REJECTED;
     }

     if ((flags & X509_TRUST_DO_SS_COMPAT) == 0)
         return X509_TRUST_UNTRUSTED;

     /*
      * Not rejected, and there is no list of accepted uses, try compat.
      */
     return trust_compat(NULL, x, flags);
 }
	/*
	* Copyright 1999-2021 The OpenSSL Project Authors. All Rights Reserved.
	*
	* Licensed under the Apache License 2.0 (the "License"). You may not use
	* this file except in compliance with the License. You can obtain a copy
	* in the file LICENSE in the source distribution or at
	* https://www.openssl.org/source/license.html
	*/

	#include <stdio.h>
	#include "internal/cryptlib.h"
	#include <openssl/x509v3.h>
	#include "crypto/x509.h"

	static int tr_cmp(const X509_TRUST const a, const X509_TRUST const b);
	static void trtable_free(X509_TRUST *p);

	static int trust_1oidany(X509_TRUST trust, X509 x, int flags);
	static int trust_1oid(X509_TRUST trust, X509 x, int flags);
	static int trust_compat(X509_TRUST trust, X509 x, int flags);

	static int obj_trust(int id, X509 *x, int flags);
	static int (default_trust) (int id, X509 x, int flags) = obj_trust;

	/*
	* WARNING: the following table should be kept in order of trust and without
	* any gaps so we can just subtract the minimum trust value to get an index
	* into the table
	*/

	static X509_TRUST trstandard[] = {
	{X509_TRUST_COMPAT, 0, trust_compat, "compatible", 0, NULL},
	{X509_TRUST_SSL_CLIENT, 0, trust_1oidany, "SSL Client", NID_client_auth,
	NULL},
	{X509_TRUST_SSL_SERVER, 0, trust_1oidany, "SSL Server", NID_server_auth,
	NULL},
	{X509_TRUST_EMAIL, 0, trust_1oidany, "S/MIME email", NID_email_protect,
	NULL},
	{X509_TRUST_OBJECT_SIGN, 0, trust_1oidany, "Object Signer", NID_code_sign,
	NULL},
	{X509_TRUST_OCSP_SIGN, 0, trust_1oid, "OCSP responder", NID_OCSP_sign,
	NULL},
	{X509_TRUST_OCSP_REQUEST, 0, trust_1oid, "OCSP request", NID_ad_OCSP,
	NULL},
	{X509_TRUST_TSA, 0, trust_1oidany, "TSA server", NID_time_stamp, NULL}
	};

	#define X509_TRUST_COUNT OSSL_NELEM(trstandard)

	static STACK_OF(X509_TRUST) *trtable = NULL;

	static int tr_cmp(const X509_TRUST const a, const X509_TRUST const b)
	{
	return (a)->trust - (b)->trust;
	}

	int (X509_TRUST_set_default(int (trust) (int, X509 , int))) (int, X509 ,
	int) {
	int (oldtrust) (int, X509 , int);
	oldtrust = default_trust;
	default_trust = trust;
	return oldtrust;
	}

	int X509_check_trust(X509 *x, int id, int flags)
	{
	X509_TRUST *pt;
	int idx;

	/* We get this as a default value */
	if (id == X509_TRUST_DEFAULT)
	return obj_trust(NID_anyExtendedKeyUsage, x,
	flags \| X509_TRUST_DO_SS_COMPAT);
	idx = X509_TRUST_get_by_id(id);
	if (idx < 0)
	return default_trust(id, x, flags);
	pt = X509_TRUST_get0(idx);
	return pt->check_trust(pt, x, flags);
	}

	int X509_TRUST_get_count(void)
	{
	if (!trtable)
	return X509_TRUST_COUNT;
	return sk_X509_TRUST_num(trtable) + X509_TRUST_COUNT;
	}

	X509_TRUST *X509_TRUST_get0(int idx)
	{
	if (idx < 0)
	return NULL;
	if (idx < (int)X509_TRUST_COUNT)
	return trstandard + idx;
	return sk_X509_TRUST_value(trtable, idx - X509_TRUST_COUNT);
	}

	int X509_TRUST_get_by_id(int id)
	{
	X509_TRUST tmp;
	int idx;

	if ((id >= X509_TRUST_MIN) && (id <= X509_TRUST_MAX))
	return id - X509_TRUST_MIN;
	if (trtable == NULL)
	return -1;
	tmp.trust = id;
	idx = sk_X509_TRUST_find(trtable, &tmp);
	if (idx < 0)
	return -1;
	return idx + X509_TRUST_COUNT;
	}

	int X509_TRUST_set(int *t, int trust)
	{
	if (X509_TRUST_get_by_id(trust) < 0) {
	ERR_raise(ERR_LIB_X509, X509_R_INVALID_TRUST);
	return 0;
	}
	*t = trust;
	return 1;
	}

	int X509_TRUST_add(int id, int flags, int (ck) (X509_TRUST , X509 *, int),
	const char name, int arg1, void arg2)
	{
	int idx;
	X509_TRUST *trtmp;
	/*
	* This is set according to what we change: application can't set it
	*/
	flags &= ~X509_TRUST_DYNAMIC;
	/* This will always be set for application modified trust entries */
	flags \|= X509_TRUST_DYNAMIC_NAME;
	/* Get existing entry if any */
	idx = X509_TRUST_get_by_id(id);
	/* Need a new entry */
	if (idx < 0) {
	if ((trtmp = OPENSSL_malloc(sizeof(*trtmp))) == NULL) {
	ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
	return 0;
	}
	trtmp->flags = X509_TRUST_DYNAMIC;
	} else
	trtmp = X509_TRUST_get0(idx);

	/* OPENSSL_free existing name if dynamic */
	if (trtmp->flags & X509_TRUST_DYNAMIC_NAME)
	OPENSSL_free(trtmp->name);
	/* dup supplied name */
	if ((trtmp->name = OPENSSL_strdup(name)) == NULL) {
	ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
	goto err;
	}
	/* Keep the dynamic flag of existing entry */
	trtmp->flags &= X509_TRUST_DYNAMIC;
	/* Set all other flags */
	trtmp->flags \|= flags;

	trtmp->trust = id;
	trtmp->check_trust = ck;
	trtmp->arg1 = arg1;
	trtmp->arg2 = arg2;

	/* If its a new entry manage the dynamic table */
	if (idx < 0) {
	if (trtable == NULL
	&& (trtable = sk_X509_TRUST_new(tr_cmp)) == NULL) {
	ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
	goto err;
	}
	if (!sk_X509_TRUST_push(trtable, trtmp)) {
	ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
	goto err;
	}
	}
	return 1;
	err:
	if (idx < 0) {
	OPENSSL_free(trtmp->name);
	OPENSSL_free(trtmp);
	}
	return 0;
	}

	static void trtable_free(X509_TRUST *p)
	{
	if (p == NULL)
	return;
	if (p->flags & X509_TRUST_DYNAMIC) {
	if (p->flags & X509_TRUST_DYNAMIC_NAME)
	OPENSSL_free(p->name);
	OPENSSL_free(p);
	}
	}

	void X509_TRUST_cleanup(void)
	{
	sk_X509_TRUST_pop_free(trtable, trtable_free);
	trtable = NULL;
	}

	int X509_TRUST_get_flags(const X509_TRUST *xp)
	{
	return xp->flags;
	}

	char X509_TRUST_get0_name(const X509_TRUST xp)
	{
	return xp->name;
	}

	int X509_TRUST_get_trust(const X509_TRUST *xp)
	{
	return xp->trust;
	}

	static int trust_1oidany(X509_TRUST trust, X509 x, int flags)
	{
	/*
	* Declare the chain verified if the desired trust OID is not rejected in
	* any auxiliary trust info for this certificate, and the OID is either
	* expressly trusted, or else either "anyEKU" is trusted, or the
	* certificate is self-signed and X509_TRUST_NO_SS_COMPAT is not set.
	*/
	flags \|= X509_TRUST_DO_SS_COMPAT \| X509_TRUST_OK_ANY_EKU;
	return obj_trust(trust->arg1, x, flags);
	}

	static int trust_1oid(X509_TRUST trust, X509 x, int flags)
	{
	/*
	* Declare the chain verified only if the desired trust OID is not
	* rejected and is expressly trusted. Neither "anyEKU" nor "compat"
	* trust in self-signed certificates apply.
	*/
	flags &= ~(X509_TRUST_DO_SS_COMPAT \| X509_TRUST_OK_ANY_EKU);
	return obj_trust(trust->arg1, x, flags);
	}

	static int trust_compat(X509_TRUST trust, X509 x, int flags)
	{
	/* Call for side-effect of setting EXFLAG_SS for self-signed-certs */
	if (X509_check_purpose(x, -1, 0) != 1)
	return X509_TRUST_UNTRUSTED;
	if ((flags & X509_TRUST_NO_SS_COMPAT) == 0 && (x->ex_flags & EXFLAG_SS))
	return X509_TRUST_TRUSTED;
	else
	return X509_TRUST_UNTRUSTED;
	}

	static int obj_trust(int id, X509 *x, int flags)
	{
	X509_CERT_AUX *ax = x->aux;
	int i;

	if (ax && ax->reject) {
	for (i = 0; i < sk_ASN1_OBJECT_num(ax->reject); i++) {
	ASN1_OBJECT *obj = sk_ASN1_OBJECT_value(ax->reject, i);
	int nid = OBJ_obj2nid(obj);

	if (nid == id \|\| (nid == NID_anyExtendedKeyUsage &&
	(flags & X509_TRUST_OK_ANY_EKU)))
	return X509_TRUST_REJECTED;
	}
	}

	if (ax && ax->trust) {
	for (i = 0; i < sk_ASN1_OBJECT_num(ax->trust); i++) {
	ASN1_OBJECT *obj = sk_ASN1_OBJECT_value(ax->trust, i);
	int nid = OBJ_obj2nid(obj);

	if (nid == id \|\| (nid == NID_anyExtendedKeyUsage &&
	(flags & X509_TRUST_OK_ANY_EKU)))
	return X509_TRUST_TRUSTED;
	}
	/*
	* Reject when explicit trust EKU are set and none match.
	*
	* Returning untrusted is enough for for full chains that end in
	* self-signed roots, because when explicit trust is specified it
	* suppresses the default blanket trust of self-signed objects.
	*
	* But for partial chains, this is not enough, because absent a similar
	* trust-self-signed policy, non matching EKUs are indistinguishable
	* from lack of EKU constraints.
	*
	* Therefore, failure to match any trusted purpose must trigger an
	* explicit reject.
	*/
	return X509_TRUST_REJECTED;
	}

	if ((flags & X509_TRUST_DO_SS_COMPAT) == 0)
	return X509_TRUST_UNTRUSTED;

	/*
	* Not rejected, and there is no list of accepted uses, try compat.
	*/
	return trust_compat(NULL, x, flags);
	}