Constify s2i_ASN1_INTEGER

Reviewed-by: NMatt Caswell <matt@openssl.org>
Reviewed-by: NKurt Roeckx <kurt@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1074)

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;
             }

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;

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);