diff --git a/crypto/asn1/asn1_gen.c b/crypto/asn1/asn1_gen.c
index a2e1c640db97a9a5f34cf0a05b394fd90ae0143d..0ad886c499f988910bf8d8d627f873527ec382ef 100644
--- a/crypto/asn1/asn1_gen.c
+++ b/crypto/asn1/asn1_gen.c
@@ -621,7 +621,7 @@ static ASN1_TYPE *asn1_str2type(const char *str, int format, int utype)
             goto bad_form;
         }
         if ((atmp->value.integer
-                    = s2i_ASN1_INTEGER(NULL, (char *)str)) == NULL) {
+                    = s2i_ASN1_INTEGER(NULL, str)) == NULL) {
             ASN1err(ASN1_F_ASN1_STR2TYPE, ASN1_R_ILLEGAL_INTEGER);
             goto bad_str;
         }
@@ -694,7 +694,7 @@ static ASN1_TYPE *asn1_str2type(const char *str, int format, int utype)
         }
 
         if (format == ASN1_GEN_FORMAT_HEX) {
-            if ((rdata = OPENSSL_hexstr2buf((char *)str, &rdlen)) == NULL) {
+            if ((rdata = OPENSSL_hexstr2buf(str, &rdlen)) == NULL) {
                 ASN1err(ASN1_F_ASN1_STR2TYPE, ASN1_R_ILLEGAL_HEX);
                 goto bad_str;
             }
diff --git a/crypto/x509v3/v3_utl.c b/crypto/x509v3/v3_utl.c
index 6fb672f89e0bae915436c6749a8adc78037abf6b..ad83de00acef580992342d3937bf02e85eaf0fc8 100644
--- a/crypto/x509v3/v3_utl.c
+++ b/crypto/x509v3/v3_utl.c
@@ -122,7 +122,7 @@ char *i2s_ASN1_INTEGER(X509V3_EXT_METHOD *method, ASN1_INTEGER *a)
     return strtmp;
 }
 
-ASN1_INTEGER *s2i_ASN1_INTEGER(X509V3_EXT_METHOD *method, char *value)
+ASN1_INTEGER *s2i_ASN1_INTEGER(X509V3_EXT_METHOD *method, const char *value)
 {
     BIGNUM *bn = NULL;
     ASN1_INTEGER *aint;
diff --git a/include/openssl/x509v3.h b/include/openssl/x509v3.h
index 299a114c7001950f759a1dbdeefdb941b480a432..a1274afe4f75154fb0a5d5176a0b10e67a6fc7e2 100644
--- a/include/openssl/x509v3.h
+++ b/include/openssl/x509v3.h
@@ -610,7 +610,7 @@ int X509V3_add_value_bool(const char *name, int asn1_bool,
 int X509V3_add_value_int(const char *name, ASN1_INTEGER *aint,
                          STACK_OF(CONF_VALUE) **extlist);
 char *i2s_ASN1_INTEGER(X509V3_EXT_METHOD *meth, ASN1_INTEGER *aint);
-ASN1_INTEGER *s2i_ASN1_INTEGER(X509V3_EXT_METHOD *meth, char *value);
+ASN1_INTEGER *s2i_ASN1_INTEGER(X509V3_EXT_METHOD *meth, const char *value);
 char *i2s_ASN1_ENUMERATED(X509V3_EXT_METHOD *meth, ASN1_ENUMERATED *aint);
 char *i2s_ASN1_ENUMERATED_TABLE(X509V3_EXT_METHOD *meth,
                                 ASN1_ENUMERATED *aint);