MPPC_HDRLEN
outlen = MPPC_HDRLEN + inlen;
dest = outbuf + MPPC_HDRLEN;
destCnt = outlen - MPPC_HDRLEN;
bcopy(inbuf, outbuf + MPPC_HDRLEN, inlen);
outlen = MPPC_HDRLEN + inlen;
rc4_crypt(&d->rc4, outbuf + MPPC_HDRLEN,
outbuf + MPPC_HDRLEN, outlen - MPPC_HDRLEN);
if (m->m_pkthdr.len < MPPC_HDRLEN)
m_copydata(m, 0, MPPC_HDRLEN, &header);
len = m->m_pkthdr.len - MPPC_HDRLEN;
m_copydata(m, MPPC_HDRLEN, len, buf);
M_PREPEND(m, MPPC_HDRLEN, M_NOWAIT);
if (m->m_pkthdr.len < MPPC_HDRLEN) {
m_copydata(m, 0, MPPC_HDRLEN, &header);
m_adj(m, MPPC_HDRLEN);