x509_att.c: improve error checking and reporting and coding style

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: David von Oheimb <david.von.oheimb@siemens.com>
(Merged from https://github.com/openssl/openssl/pull/18931)

1 files changed, 58 insertions, 38 deletions

diff --git a/crypto/x509/x509_att.c b/crypto/x509/x509_att.c
index 73ac59454d..9e6434187c 100644
--- a/crypto/x509/x509_att.c
+++ b/crypto/x509/x509_att.c
@@ -55,20 +55,28 @@ int X509at_get_attr_by_OBJ(const STACK_OF(X509_ATTRIBUTE) *sk,
 
 X509_ATTRIBUTE *X509at_get_attr(const STACK_OF(X509_ATTRIBUTE) *x, int loc)
 {
-    if (x == NULL || sk_X509_ATTRIBUTE_num(x) <= loc || loc < 0)
+    if (x == NULL) {
+        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
         return NULL;
-
+    }
+    if (sk_X509_ATTRIBUTE_num(x) <= loc || loc < 0) {
+        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_INVALID_ARGUMENT);
+        return NULL;
+    }
     return sk_X509_ATTRIBUTE_value(x, loc);
 }
 
 X509_ATTRIBUTE *X509at_delete_attr(STACK_OF(X509_ATTRIBUTE) *x, int loc)
 {
-    X509_ATTRIBUTE *ret;
-
-    if (x == NULL || sk_X509_ATTRIBUTE_num(x) <= loc || loc < 0)
+    if (x == NULL) {
+        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
         return NULL;
-    ret = sk_X509_ATTRIBUTE_delete(x, loc);
-    return ret;
+    }
+    if (sk_X509_ATTRIBUTE_num(x) <= loc || loc < 0) {
+        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_INVALID_ARGUMENT);
+        return NULL;
+    }
+    return sk_X509_ATTRIBUTE_delete(x, loc);
 }
 
 STACK_OF(X509_ATTRIBUTE) *X509at_add1_attr(STACK_OF(X509_ATTRIBUTE) **x,
@@ -77,10 +85,14 @@ STACK_OF(X509_ATTRIBUTE) *X509at_add1_attr(STACK_OF(X509_ATTRIBUTE) **x,
     X509_ATTRIBUTE *new_attr = NULL;
     STACK_OF(X509_ATTRIBUTE) *sk = NULL;
 
-    if (x == NULL) {
+    if (x == NULL || attr == NULL) {
         ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
         return NULL;
     }
+    if (X509at_get_attr_by_OBJ(sk, attr->object, -1) != -1) {
+        ERR_raise(ERR_LIB_X509, X509_R_DUPLICATE_ATTRIBUTE);
+        return NULL;
+    }
 
     if (*x == NULL) {
         if ((sk = sk_X509_ATTRIBUTE_new_null()) == NULL)
@@ -113,8 +125,9 @@ STACK_OF(X509_ATTRIBUTE) *X509at_add1_attr_by_OBJ(STACK_OF(X509_ATTRIBUTE)
 {
     X509_ATTRIBUTE *attr;
     STACK_OF(X509_ATTRIBUTE) *ret;
+
     attr = X509_ATTRIBUTE_create_by_OBJ(NULL, obj, type, bytes, len);
-    if (!attr)
+    if (attr == NULL)
         return 0;
     ret = X509at_add1_attr(x, attr);
     X509_ATTRIBUTE_free(attr);
@@ -128,8 +141,9 @@ STACK_OF(X509_ATTRIBUTE) *X509at_add1_attr_by_NID(STACK_OF(X509_ATTRIBUTE)
 {
     X509_ATTRIBUTE *attr;
     STACK_OF(X509_ATTRIBUTE) *ret;
+
     attr = X509_ATTRIBUTE_create_by_NID(NULL, nid, type, bytes, len);
-    if (!attr)
+    if (attr == NULL)
         return 0;
     ret = X509at_add1_attr(x, attr);
     X509_ATTRIBUTE_free(attr);
@@ -144,8 +158,9 @@ STACK_OF(X509_ATTRIBUTE) *X509at_add1_attr_by_txt(STACK_OF(X509_ATTRIBUTE)
 {
     X509_ATTRIBUTE *attr;
     STACK_OF(X509_ATTRIBUTE) *ret;
+
     attr = X509_ATTRIBUTE_create_by_txt(NULL, attrname, type, bytes, len);
-    if (!attr)
+    if (attr == NULL)
         return 0;
     ret = X509at_add1_attr(x, attr);
     X509_ATTRIBUTE_free(attr);
@@ -155,29 +170,26 @@ STACK_OF(X509_ATTRIBUTE) *X509at_add1_attr_by_txt(STACK_OF(X509_ATTRIBUTE)
 void *X509at_get0_data_by_OBJ(const STACK_OF(X509_ATTRIBUTE) *x,
                               const ASN1_OBJECT *obj, int lastpos, int type)
 {
-    int i;
+    int i = X509at_get_attr_by_OBJ(x, obj, lastpos);
     X509_ATTRIBUTE *at;
-    i = X509at_get_attr_by_OBJ(x, obj, lastpos);
+
     if (i == -1)
         return NULL;
-    if ((lastpos <= -2) && (X509at_get_attr_by_OBJ(x, obj, i) != -1))
+    if (lastpos <= -2 && X509at_get_attr_by_OBJ(x, obj, i) != -1)
         return NULL;
     at = X509at_get_attr(x, i);
-    if (lastpos <= -3 && (X509_ATTRIBUTE_count(at) != 1))
+    if (lastpos <= -3 && X509_ATTRIBUTE_count(at) != 1)
         return NULL;
     return X509_ATTRIBUTE_get0_data(at, 0, type, NULL);
 }
 
 STACK_OF(X509_ATTRIBUTE) *ossl_x509at_dup(const STACK_OF(X509_ATTRIBUTE) *x)
 {
-    int i, n;
+    int i, n = sk_X509_ATTRIBUTE_num(x);
     STACK_OF(X509_ATTRIBUTE) *sk = NULL;
 
-    n = sk_X509_ATTRIBUTE_num(x);
     for (i = 0; i < n; ++i) {
-        X509_ATTRIBUTE *attr = sk_X509_ATTRIBUTE_value(x, i);
-
-        if (X509at_add1_attr(&sk, attr) == NULL) {
+        if (X509at_add1_attr(&sk, sk_X509_ATTRIBUTE_value(x, i)) == NULL) {
             sk_X509_ATTRIBUTE_pop_free(sk, X509_ATTRIBUTE_free);
             return NULL;
         }
@@ -189,10 +201,9 @@ X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_NID(X509_ATTRIBUTE **attr, int nid,
                                              int atrtype, const void *data,
                                              int len)
 {
-    ASN1_OBJECT *obj;
+    ASN1_OBJECT *obj = OBJ_nid2obj(nid);
     X509_ATTRIBUTE *ret;
 
-    obj = OBJ_nid2obj(nid);
     if (obj == NULL) {
         ERR_raise(ERR_LIB_X509, X509_R_UNKNOWN_NID);
         return NULL;
@@ -210,24 +221,25 @@ X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_OBJ(X509_ATTRIBUTE **attr,
 {
     X509_ATTRIBUTE *ret;
 
-    if ((attr == NULL) || (*attr == NULL)) {
+    if (attr == NULL || *attr == NULL) {
         if ((ret = X509_ATTRIBUTE_new()) == NULL) {
             ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
             return NULL;
         }
-    } else
+    } else {
         ret = *attr;
+    }
 
     if (!X509_ATTRIBUTE_set1_object(ret, obj))
         goto err;
     if (!X509_ATTRIBUTE_set1_data(ret, atrtype, data, len))
         goto err;
 
-    if ((attr != NULL) && (*attr == NULL))
+    if (attr != NULL && *attr == NULL)
         *attr = ret;
     return ret;
  err:
-    if ((attr == NULL) || (ret != *attr))
+    if (attr == NULL || ret != *attr)
         X509_ATTRIBUTE_free(ret);
     return NULL;
 }
@@ -237,10 +249,9 @@ X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_txt(X509_ATTRIBUTE **attr,
                                              const unsigned char *bytes,
                                              int len)
 {
-    ASN1_OBJECT *obj;
+    ASN1_OBJECT *obj = OBJ_txt2obj(atrname, 0);
     X509_ATTRIBUTE *nattr;
 
-    obj = OBJ_txt2obj(atrname, 0);
     if (obj == NULL) {
         ERR_raise_data(ERR_LIB_X509, X509_R_INVALID_FIELD_NAME,
                        "name=%s", atrname);
@@ -253,8 +264,10 @@ X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_txt(X509_ATTRIBUTE **attr,
 
 int X509_ATTRIBUTE_set1_object(X509_ATTRIBUTE *attr, const ASN1_OBJECT *obj)
 {
-    if ((attr == NULL) || (obj == NULL))
+    if (attr == NULL || obj == NULL) {
+        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
         return 0;
+    }
     ASN1_OBJECT_free(attr->object);
     attr->object = OBJ_dup(obj);
     return attr->object != NULL;
@@ -266,12 +279,15 @@ int X509_ATTRIBUTE_set1_data(X509_ATTRIBUTE *attr, int attrtype,
     ASN1_TYPE *ttmp = NULL;
     ASN1_STRING *stmp = NULL;
     int atype = 0;
-    if (!attr)
+
+    if (attr == NULL) {
+        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
         return 0;
-    if (attrtype & MBSTRING_FLAG) {
+    }
+    if ((attrtype & MBSTRING_FLAG) != 0) {
         stmp = ASN1_STRING_set_by_NID(NULL, data, len, attrtype,
                                       OBJ_obj2nid(attr->object));
-        if (!stmp) {
+        if (stmp == NULL) {
             ERR_raise(ERR_LIB_X509, ERR_R_ASN1_LIB);
             return 0;
         }
@@ -294,7 +310,7 @@ int X509_ATTRIBUTE_set1_data(X509_ATTRIBUTE *attr, int attrtype,
     }
     if ((ttmp = ASN1_TYPE_new()) == NULL)
         goto err;
-    if ((len == -1) && !(attrtype & MBSTRING_FLAG)) {
+    if (len == -1 && (attrtype & MBSTRING_FLAG) == 0) {
         if (!ASN1_TYPE_set1(ttmp, attrtype, data))
             goto err;
     } else {
@@ -320,17 +336,19 @@ int X509_ATTRIBUTE_count(const X509_ATTRIBUTE *attr)
 
 ASN1_OBJECT *X509_ATTRIBUTE_get0_object(X509_ATTRIBUTE *attr)
 {
-    if (attr == NULL)
+    if (attr == NULL) {
+        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
         return NULL;
+    }
     return attr->object;
 }
 
 void *X509_ATTRIBUTE_get0_data(X509_ATTRIBUTE *attr, int idx,
                                int atrtype, void *data)
 {
-    ASN1_TYPE *ttmp;
-    ttmp = X509_ATTRIBUTE_get0_type(attr, idx);
-    if (!ttmp)
+    ASN1_TYPE *ttmp = X509_ATTRIBUTE_get0_type(attr, idx);
+
+    if (ttmp == NULL)
         return NULL;
     if (atrtype == V_ASN1_BOOLEAN
             || atrtype == V_ASN1_NULL
@@ -343,7 +361,9 @@ void *X509_ATTRIBUTE_get0_data(X509_ATTRIBUTE *attr, int idx,
 
 ASN1_TYPE *X509_ATTRIBUTE_get0_type(X509_ATTRIBUTE *attr, int idx)
 {
-    if (attr == NULL)
+    if (attr == NULL) {
+        ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
         return NULL;
+    }
     return sk_ASN1_TYPE_value(attr->set, idx);
 }