Use 'unsigned char *' for bytes

connection_info.c:156:17: error: initializing 'const char *' with an expression of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    const char *binary = KeyBinaryHash(connection_key, &real_length);
                ^        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
connection_info.c:161:12: error: returning 'const char *' from a function with result type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    return binary;
           ^~~~~~
2 errors generated.
make[2]: *** [Makefile:561: connection_info.lo] Error 1
make[2]: *** Waiting for unfinished jobs....
client_protocol.c:239:44: error: passing 'char [4096]' to parameter of type 'unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    nonce_len = BN_bn2mpi(nonce_challenge, in);
                                           ^~
/usr/include/openssl/bn.h:227:47: note: passing argument to parameter 'to' here
int BN_bn2mpi(const BIGNUM *a, unsigned char *to);
                                              ^
client_protocol.c:275:43: error: passing 'char [4096]' to parameter of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        if (RSA_public_encrypt(nonce_len, in, out, server_pubkey, RSA_PKCS1_PADDING) <= 0)
                                          ^~
/usr/include/openssl/rsa.h:255:55: note: passing argument to parameter 'from' here
int RSA_public_encrypt(int flen, const unsigned char *from,
                                                      ^
client_protocol.c:275:47: error: passing 'char *' to parameter of type 'unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        if (RSA_public_encrypt(nonce_len, in, out, server_pubkey, RSA_PKCS1_PADDING) <= 0)
                                              ^~~
/usr/include/openssl/rsa.h:256:39: note: passing argument to parameter 'to' here
                       unsigned char *to, RSA *rsa, int padding);
                                      ^
client_protocol.c:307:31: error: passing 'char [8192]' to parameter of type 'unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    len = BN_bn2mpi(pubkey_n, sendbuffer);
                              ^~~~~~~~~~
/usr/include/openssl/bn.h:227:47: note: passing argument to parameter 'to' here
int BN_bn2mpi(const BIGNUM *a, unsigned char *to);
                                              ^
client_protocol.c:312:31: error: passing 'char [8192]' to parameter of type 'unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    len = BN_bn2mpi(pubkey_e, sendbuffer);
                              ^~~~~~~~~~
/usr/include/openssl/bn.h:227:47: note: passing argument to parameter 'to' here
int BN_bn2mpi(const BIGNUM *a, unsigned char *to);
                                              ^
client_protocol.c:347:30: error: passing 'char [4096]' to parameter of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    if ((HashesMatch(digest, in, CF_DEFAULT_DIGEST)) ||
                             ^~
../libntech/libutils/hash.h:158:25: note: passing argument to parameter 'digest2' here
    const unsigned char digest2[EVP_MAX_MD_SIZE + 1],
                        ^
client_protocol.c:348:30: error: passing 'char [4096]' to parameter of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        (HashesMatch(digest, in, HASH_METHOD_MD5)))  // Legacy
                             ^~
../libntech/libutils/hash.h:158:25: note: passing argument to parameter 'digest2' here
    const unsigned char digest2[EVP_MAX_MD_SIZE + 1],
                        ^
client_protocol.c:400:44: error: passing 'char [4096]' to parameter of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    if (RSA_private_decrypt(encrypted_len, in, decrypted_cchall, PRIVKEY, RSA_PKCS1_PADDING) <= 0)
                                           ^~
/usr/include/openssl/rsa.h:261:56: note: passing argument to parameter 'from' here
int RSA_private_decrypt(int flen, const unsigned char *from,
                                                       ^
client_protocol.c:400:48: error: passing 'char *' to parameter of type 'unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    if (RSA_private_decrypt(encrypted_len, in, decrypted_cchall, PRIVKEY, RSA_PKCS1_PADDING) <= 0)
                                               ^~~~~~~~~~~~~~~~
/usr/include/openssl/rsa.h:262:40: note: passing argument to parameter 'to' here
                        unsigned char *to, RSA *rsa, int padding);
                                       ^
client_protocol.c:421:42: error: passing 'unsigned char [65]' to parameter of type 'const char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        SendTransaction(conn->conn_info, digest, CF_DEFAULT_DIGEST_LEN, CF_DONE);
                                         ^~~~~~
./net.h:37:60: note: passing argument to parameter 'buffer' here
int SendTransaction(ConnectionInfo *conn_info, const char *buffer, int len, char status);
                                                           ^
client_protocol.c:425:42: error: passing 'unsigned char [65]' to parameter of type 'const char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        SendTransaction(conn->conn_info, digest, CF_MD5_LEN, CF_DONE);
                                         ^~~~~~
./net.h:37:60: note: passing argument to parameter 'buffer' here
int SendTransaction(ConnectionInfo *conn_info, const char *buffer, int len, char status);
                                                           ^
client_protocol.c:446:35: error: passing 'char [4096]' to parameter of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        if ((newkey_n = BN_mpi2bn(in, len, NULL)) == NULL)
                                  ^~
/usr/include/openssl/bn.h:226:40: note: passing argument to parameter 's' here
BIGNUM *BN_mpi2bn(const unsigned char *s, int len, BIGNUM *ret);
                                       ^
client_protocol.c:466:35: error: passing 'char [4096]' to parameter of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        if ((newkey_e = BN_mpi2bn(in, len, NULL)) == NULL)
                                  ^~
/usr/include/openssl/bn.h:226:40: note: passing argument to parameter 's' here
BIGNUM *BN_mpi2bn(const unsigned char *s, int len, BIGNUM *ret);
                                       ^
client_protocol.c:510:61: error: passing 'char *' to parameter of type 'unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    if (RSA_public_encrypt(session_size, conn->session_key, out, server_pubkey, RSA_PKCS1_PADDING) <= 0)
                                                            ^~~
/usr/include/openssl/rsa.h:256:39: note: passing argument to parameter 'to' here
                       unsigned char *to, RSA *rsa, int padding);
                                      ^
client_protocol.c:531:29: error: passing 'const unsigned char *' to parameter of type 'const char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
    LastSaw(conn->remoteip, KeyBinaryHash(conn->conn_info->remote_key, &length), LAST_SEEN_ROLE_CONNECT);
                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../libpromises/lastseen.h:46:49: note: passing argument to parameter 'digest' here
void LastSaw(const char *ipaddress, const char *digest, LastSeenRole role);
                                                ^
15 errors generated.
make[2]: *** [Makefile:561: client_protocol.lo] Error 1
client_code.c:659:44: error: passing 'char [4096]' to parameter of type 'unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        if (!EVP_DecryptUpdate(crypto_ctx, workbuf, &plainlen, buf, cipherlen))
                                           ^~~~~~~
/usr/include/openssl/evp.h:599:70: note: passing argument to parameter 'out' here
/*__owur*/ int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
                                                                     ^
client_code.c:659:64: error: passing 'char *' to parameter of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        if (!EVP_DecryptUpdate(crypto_ctx, workbuf, &plainlen, buf, cipherlen))
                                                               ^~~
/usr/include/openssl/evp.h:600:66: note: passing argument to parameter 'in' here
                                 int *outl, const unsigned char *in, int inl);
                                                                 ^
client_code.c:667:46: error: passing 'char *' to parameter of type 'unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
        if (!EVP_DecryptFinal_ex(crypto_ctx, workbuf + plainlen, &finlen))
                                             ^~~~~~~~~~~~~~~~~~
/usr/include/openssl/evp.h:603:72: note: passing argument to parameter 'outm' here
/*__owur*/ int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm,
                                                                       ^
3 errors generated.
make[2]: *** [Makefile:561: client_code.lo] Error 1
tls_generic.c:493:39: error: passing 'const char *' to parameter of type 'const unsigned char *' converts between pointers to integer types with different sign [-Werror,-Wpointer-sign]
                                      (const char *) "a",
                                      ^~~~~~~~~~~~~~~~~~
/usr/include/openssl/x509.h:832:53: note: passing argument to parameter 'bytes' here
                               const unsigned char *bytes, int len, int loc,
                                                    ^