Comment side-effect only calls of X509_check_purpose

Reviewed-by: NRich Salz <rsalz@openssl.org>

crypto/cms/cms_sd.c

@@ -280,6 +280,7 @@ CMS_SignerInfo *CMS_add1_signer(CMS_ContentInfo *cms,
     si = M_ASN1_new_of(CMS_SignerInfo);
     if (!si)
         goto merr;
+    /* Call for side-effect of computing hash and caching extensions */
     X509_check_purpose(signer, -1, -1);
 
     CRYPTO_add(&pk->references, 1, CRYPTO_LOCK_EVP_PKEY);

crypto/ts/ts_rsp_sign.c

@@ -793,6 +793,7 @@ static ESS_CERT_ID *ess_CERT_ID_new_init(X509 *cert, int issuer_needed)
     GENERAL_NAME *name = NULL;
     unsigned char cert_sha1[SHA_DIGEST_LENGTH];
 
+    /* Call for side-effect of computing hash and caching extensions */
     X509_check_purpose(cert, -1, 0);
     if ((cid = ESS_CERT_ID_new()) == NULL)
         goto err;

crypto/x509/x509_trs.c

@@ -283,6 +283,7 @@ static int trust_1oid(X509_TRUST *trust, X509 *x, int flags)
 
 static int trust_compat(X509_TRUST *trust, X509 *x, int flags)
 {
+    /* Call for side-effect of computing hash and caching extensions */
     X509_check_purpose(x, -1, 0);
     if (x->ex_flags & EXFLAG_SS)
         return X509_TRUST_TRUSTED;

crypto/x509v3/pcy_tree.c

@@ -186,7 +186,6 @@ static int tree_init(X509_POLICY_TREE **ptree, STACK_OF(X509) *certs,
         uint32_t ex_flags;
         x = sk_X509_value(certs, i);
         ex_flags = X509_get_extension_flags(x);
-        X509_check_purpose(x, -1, -1);
         cache = policy_cache_set(x);
         /* If cache NULL something bad happened: return immediately */
         if (cache == NULL)

crypto/x509v3/v3_purp.c

@@ -132,6 +132,7 @@ int X509_check_purpose(X509 *x, int id, int ca)
         x509v3_cache_extensions(x);
         CRYPTO_w_unlock(CRYPTO_LOCK_X509);
     }
+    /* Return if side-effect only call */
     if (id == -1)
         return 1;
     idx = X509_PURPOSE_get_by_id(id);
@@ -850,12 +851,14 @@ int X509_check_akid(X509 *issuer, AUTHORITY_KEYID *akid)
 
 uint32_t X509_get_extension_flags(X509 *x)
 {
+    /* Call for side-effect of computing hash and caching extensions */
     X509_check_purpose(x, -1, -1);
     return x->ex_flags;
 }
 
 uint32_t X509_get_key_usage(X509 *x)
 {
+    /* Call for side-effect of computing hash and caching extensions */
     X509_check_purpose(x, -1, -1);
     if (x->ex_flags & EXFLAG_KUSAGE)
         return x->ex_kusage;
@@ -864,6 +867,7 @@ uint32_t X509_get_key_usage(X509 *x)
 
 uint32_t X509_get_extended_key_usage(X509 *x)
 {
+    /* Call for side-effect of computing hash and caching extensions */
     X509_check_purpose(x, -1, -1);
     if (x->ex_flags & EXFLAG_XKUSAGE)
         return x->ex_xkusage;
@@ -872,6 +876,7 @@ uint32_t X509_get_extended_key_usage(X509 *x)
 
 const ASN1_OCTET_STRING *X509_get0_subject_key_id(X509 *x)
 {
+    /* Call for side-effect of computing hash and caching extensions */
     X509_check_purpose(x, -1, -1);
     return x->skid;
 }