ref: 20156393be201341d9b374b71ce43a7bc69a068b
dir: /msg.c/
#include <u.h> #include <libc.h> #include <draw.h> #include "dat.h" #include "fns.h" enum /* Rdpnego.type */ { Tnego= 1, Rnego= 2, }; typedef struct Rdpnego Rdpnego; struct Rdpnego { int type; int flags; int proto; }; static int putnego(uchar* b, uint nb, Rdpnego* m) { int len; len = 8; if(nb < 8){ werrstr(Esmall); return -1; } b[0] = m->type; b[1] = m->flags; PSHORT(b+2, len); PLONG(b+4, m->proto); return len; } static int getnego(Rdpnego* m, uchar* b, uint nb) { int len; if(nb < 8){ werrstr(Eshort); return -1; } m->type = b[0]; m->flags = b[1]; len = GSHORT(b+2); m->proto = GLONG(b+4); if(len != 8){ werrstr("bad length in RDP Nego Response"); return -1; } return len; } int sizesechdr(int secflags) { if(secflags&Scrypt) return 12; // flags[4] mac[8] else if(secflags) return 4; // flags[4] return 0; } uchar* txprep(uchar* buf, int nb, int ndata, int chanid, int mcsuid, int secflags) { int n, len, shdsize; uchar *p, *ep; if(chanid==0) chanid = GLOBALCHAN; shdsize = sizesechdr(secflags); len = TPDATAFIXLEN+8+shdsize+ndata; if(len>nb){ werrstr("%s: provided %d, need %d, data %d", Esmall, nb, len, ndata); return nil; } ep = buf+len; ndata = len-TPDATAFIXLEN; n = mktpdat(buf, nb, ndata); if(n < 0) sysfatal("mktpdat: %r"); p = buf+TPDATAFIXLEN; ndata -= 8; if(putmsdr(p, ep-p, ndata, chanid, mcsuid) < 0) sysfatal("putmsdr: %r"); p += 8; if(shdsize > 0) PLONG(p, secflags); return p + shdsize; } int putmsg(uchar* b, uint nb, Msg* m) { int n, nld, len; uchar *p, *ep, *q; Rdpnego neg; switch(m->type){ case Xconnect: /* 5.4.2.1 Negotiation-Based Approach */ nld = 25+8; n = mktpcr(b, nb, nld); if(n < 0) return -1; p = b+n-nld; ep = b+n; memcpy(p, "Cookie: mstshash=eltons\r\n", 25); neg = (Rdpnego){Tnego, 0, m->negproto}; if(putnego(p+25, ep-p, &neg) != 8){ werrstr("pnego failed: %r"); return -1; } return n; case Xhangup: return mktpdr(b, nb, 0); case Mattach: n = mktpdat(b, nb, 1); if(n < 0) return -1; b[TPDATAFIXLEN] = (Maur<<2); return n; case Mjoin: n = mktpdat(b, nb, 5); if(n < 0) return -1; p = b+TPDATAFIXLEN; p[0] = (Mcjr << 2); PSHORTB(p+1, m->mcsuid); PSHORTB(p+3, m->chanid); return n; case Merectdom: n = mktpdat(b, nb, 5); if(n < 0) return -1; p = b+TPDATAFIXLEN; p[0] = (Medr << 2); PSHORTB(p+1, 1); PSHORTB(p+3, 1); return n; case Mconnect: /* 2.2.1.3 Client MCS Connect Initial PDU with GCC Conference Create Request */ nld = sizegccr(m); len = mktpdat(b, nb, nld+MCSCIFIXLEN); if(len < 0){ werrstr("mktpdat: %r"); return -1; } p = b+TPDATAFIXLEN; ep = b+nb; n = mkmcsci(p, ep-p, nld); if(n != nld+MCSCIFIXLEN){ werrstr("mkmcsci: %r"); return -1; } n = putgccr(p+MCSCIFIXLEN, nld, m); if(n != nld){ werrstr("putgccr: %r"); return -1; } return len; case Dclientinfo: /* 2.2.1.11 Client Info PDU */ return putclientinfo(b, nb, m); case Mactivated: /* 2.2.1.13.2 Client Confirm Active PDU */ return putconfirmactive(b, nb, m); case Mvcdata: nld = m->ndata+8; p = txprep(b, nb, nld, m->chanid, m->originid, 0); if(p == nil) return -1; PLONG(p+0, m->len); PLONG(p+4, m->flags); memcpy(p+8, m->data, m->ndata); len = p+nld-b; return len; case Async: /* 2.2.1.14 Client Synchronize PDU */ nld = 4+SCDSIZE; if((p = txprep(b, nb, nld, 0, m->originid, 0)) == nil) return -1; len = p+nld-b; q = putsdh(p, p+nld, nld, ADsync, m->originid, m->shareid); PSHORT(q+0, 1); // sync message type PSHORT(q+2, m->mcsuid); // target MCS userId return len; case Actl: /* 2.2.1.15 Control PDU */ nld = 8+SCDSIZE; if((p = txprep(b, nb, nld, 0, m->originid, 0)) == nil) return -1; len = p+nld-b; q = putsdh(p, p+nld, nld, ADctl, m->originid, m->shareid); /* action[2] grantId[2] controlId[2] */ PSHORT(q+0, m->action); PSHORT(q+2, 0); PLONG(q+4, 0); return len; case Afontls: /* 2.2.1.18 Client Font List PDU */ nld = 8+SCDSIZE; if((p = txprep(b, nb, nld, 0, m->originid, 0)) == nil) return -1; len = p+nld-b; q = putsdh(p, p+nld, nld, ADfontlist, m->originid, m->shareid); PSHORT(q+0, 0); // numberFonts PSHORT(q+2, 0); // totalNumFonts PSHORT(q+4, 2+1); // listFlags: 1=first, 2=last PSHORT(q+6, 50); // entrySize return len; case Ainput: /* 2.2.8.1.1.3.1.1 Slow-Path Input Event (TS_INPUT_EVENT) */ nld = 16+SCDSIZE; if((p = txprep(b, nb, nld, 0, m->originid, 0)) == nil) return -1; len = p+nld-b; q = putsdh(p, p+nld, nld, ADinput, m->originid, m->shareid); PSHORT(q+0, 1); /* numEvents */ PSHORT(q+2, 0); PLONG(q+4, m->msec); PSHORT(q+8, m->mtype); PSHORT(q+10, m->flags); PSHORT(q+12, m->iarg[0]); PSHORT(q+14, m->iarg[1]); return len; case Lreq: case Lnolicense: if((nld = sizelicensemsg(m)) < 0) return -1; if((p = txprep(b, nb, nld, 0, m->originid, Slicensepk)) == nil) return -1; len = p+nld-b; if(putlicensemsg(p, nld, m) != nld){ werrstr("putlicensemsg: %r"); return -1; } return len; case Dsupress: /* 2.2.11.3 Suppress Output PDU */ nld = (m->allow?12:4)+SCDSIZE; if((p = txprep(b, nb, nld, 0, m->originid, 0)) == nil) return -1; len = p-b+nld; q = putsdh(p, p+nld, nld, ADsupress, m->originid, m->shareid); q[0] = (m->allow?1:0); memset(q+1, 3, 0); if(m->allow){ PSHORT(q+4, 0); // left PSHORT(q+6, 0); // top PSHORT(q+8, m->xsz-1); // right PSHORT(q+10, m->ysz-1); // bottom } return len; default: werrstr("putmsg: unsupported type"); return 0; } }; int getmsg(Msg* m, uchar* b, uint nb) { uchar *p, *ep; int type, mtag, btag, mr, secflg, sctlver; Rdpnego neg; p = b; ep = b+nb; if(istpkt(p, ep) == 0){ /* * 2.2.9.1.2 Server Fast-Path Update PDU * enabled with CanFastpath in General Capability Set */ if(p[0]&(1<<7)){ werrstr("legacy encryption in a Fast-Path PDU"); return -1; } if(p[1]&(1<<7)) p += 3; else p += 2; m->type = Aupdate; m->data = p; m->ndata = ep-p; m->getshare = getshareF; return nb; } type = tptype(b, b+nb); switch(type){ default: werrstr("unknown TPDU type %d", type); return -1; case ConCfrm: /* 5.4.2.1 Negotiation-Based Approach */ m->type = Xconnected; m->negproto = 0; if((p = tpdat(p, ep)) != nil && getnego(&neg, p, ep-p)) if(neg.type == Rnego) m->negproto = neg.proto; return nb; case Data: p = tpdat(p, ep); if(p+2 > ep){ werrstr(Eshort); return -1; } /* try ASN.1 PER: DomainMCSPDU are encoded this way */ mtag = p[0]>>2; switch(mtag){ default: werrstr("unknown MCS tag %d", mtag); return -1; case Mauc: m->type = Mattached; m->mcsuid = 0; mr = p[1]; if(mr != 0){ werrstr("Mauc error result: %d", mr); return -1; } if((p[0])&2){ if(p+4 > ep){ werrstr(Eshort); return -1; } m->mcsuid = GSHORTB(p+2); } return nb; case Mcjc: m->type = Mjoined; mr = p[1]; if(mr != 0){ werrstr("Mcjc error result: %d", mr); return -1; } return nb; case Mdpu: m->type = Mclosing; return nb; case Msdi: m->chanid = mcschan(b, b+nb); if(m->chanid < 0){ werrstr("%d: bad MCS channel id", m->chanid); return -1; } p = mcsdat(b, b+nb); if(p == nil) return -1; if(m->chanid != GLOBALCHAN){ m->type = Mvcdata; m->len = GLONG(p+0); m->flags = GLONG(p+4); m->data = p+8; m->ndata = ep-p-8; if(m->len > 8*1024*1024){ werrstr("bad length in virtual channel PDU header"); return -1; } return nb; } if(isflowpdu(p,ep)){ m->type = Aflow; return nb; } secflg = GSHORT(p); sctlver = GSHORT(p+2)>>4; if(secflg&Slicensepk && sctlver != 1) return getlicensemsg(m, p+4, ep-(p+4)); m->type = Aupdate; m->data = p; m->ndata = ep-p; m->getshare = getshareT; return nb; case 31: /* try ANS.1 BER: T.125 ConnectMCSPDU are encoded this way */ gbtag(p, ep, &btag); switch(btag){ case Mcr: return getmcr(m, p, ep-p); default: werrstr("unknown MCS BER tag %d", btag); return -1; } } } }; int readmsg(Rdp* c, Msg* m) { uchar* buf; int fd, n; uint nb; fd = c->fd; buf = c->rbuf; nb = sizeof c->rbuf; if((n = readpdu(fd, buf, nb)) < 0 || getmsg(m, buf, n) <= 0) return -1; return n; } int writemsg(Rdp* c, Msg* m) { uchar buf[MAXTPDU]; int fd, n; fd = c->fd; if((n = putmsg(buf, sizeof buf, m)) < 0 || writen(fd, buf, n) != n) return -1; return n; }