Convert chars to len with unsigned buffer

Introduce chars2len to compute a len out of an unsigned char buf[2].
This avoids problems when any of the chars is negative, if char is
signed.

diff --git a/rnetclient.c b/rnetclient.c
index 0ce8593..a58b62b 100644 (file)
--- a/rnetclient.c
+++ b/rnetclient.c
@@ -31,6 +31,10 @@
 #include "rnet_message.h"
 #include "rnet_encode.h"
 
 #include "rnet_message.h"
 #include "rnet_encode.h"
 

+static size_t chars2len (unsigned char buf[2]) {
+       return (buf[0] << 8 | buf[1]);
+}
+

 static void * get_creds(char *certfile)
 {
        static gnutls_certificate_credentials_t cred;
 static void * get_creds(char *certfile)
 {
        static gnutls_certificate_credentials_t cred;


@@ -94,7 +98,7 @@ static int inflateRecord(char *buffer, size_t len, char **out, size_t *olen)
        zstrm.opaque = Z_NULL;
        if ((r = inflateInit(&zstrm)) != Z_OK)
                return -1;
        zstrm.opaque = Z_NULL;
        if ((r = inflateInit(&zstrm)) != Z_OK)
                return -1;

-       *olen = (buffer[3] << 8 | buffer[4]);
+       *olen = chars2len(buffer+3);

        *out = malloc(*olen);
        if (!out) {
                inflateEnd(&zstrm);
        *out = malloc(*olen);
        if (!out) {
                inflateEnd(&zstrm);


@@ -195,7 +199,7 @@ static int rnet_recv(gnutls_session_t session, struct rnet_message **message)
        buffer = (*message)->buffer;
        r = gnutls_record_recv(session, buffer, 6);
        if (buffer[0] == 0x01) {
        buffer = (*message)->buffer;
        r = gnutls_record_recv(session, buffer, 6);
        if (buffer[0] == 0x01) {

-               len = (buffer[1] << 8 | buffer[2]);
+               len = chars2len(buffer+1);

                rnet_message_expand(message, len);
                buffer = (*message)->buffer + 6;
                r = gnutls_record_recv(session, buffer, len);
                rnet_message_expand(message, len);
                buffer = (*message)->buffer + 6;
                r = gnutls_record_recv(session, buffer, len);


@@ -207,7 +211,7 @@ static int rnet_recv(gnutls_session_t session, struct rnet_message **message)
                (*message)->len = olen;
                free(out);
        } else {
                (*message)->len = olen;
                free(out);
        } else {

-               len = (buffer[1] << 8 | buffer[2]);
+               len = chars2len(buffer+1);

                rnet_message_expand(message, len - 1);
                buffer = (*message)->buffer + 6;
                r = gnutls_record_recv(session, buffer, len - 1);
                rnet_message_expand(message, len - 1);
                buffer = (*message)->buffer + 6;
                r = gnutls_record_recv(session, buffer, len - 1);