ref: ae442b9d3008de0e1a54218ed553c139e5d405ad
parent: d3aca0398d0e0bb8358403f6fc2d247f2bffb1b4
author: cinap_lenrek <cinap_lenrek@gmx.de>
date: Sat Mar 9 12:33:58 EST 2013
add wpa key setup program aux/wpa
--- a/sys/src/cmd/aux/mkfile
+++ b/sys/src/cmd/aux/mkfile
@@ -44,6 +44,7 @@
write\
wacom\
wikifmt\
+ wpa\
zerotrunc\
BIN=/$objtype/bin/aux
--- /dev/null
+++ b/sys/src/cmd/aux/wpa.c
@@ -1,0 +1,455 @@
+#include <u.h>
+#include <libc.h>
+#include <ip.h>
+#include <mp.h>
+#include <libsec.h>
+#include <auth.h>
+
+enum {+ PTKlen = 512/8,
+ GTKlen = 256/8,
+ Noncelen = 32,
+ Eaddrlen = 6,
+};
+
+enum {+ Fptk = 1<<3,
+ Fins = 1<<6,
+ Fack = 1<<7,
+ Fmic = 1<<8,
+ Fsec = 1<<9,
+ Ferr = 1<<10,
+ Freq = 1<<11,
+ Fenc = 1<<12,
+
+ Keydescrlen = 1+2+2+8+32+16+8+8+16+2,
+};
+
+typedef struct Keydescr Keydescr;
+struct Keydescr
+{+ uchar type[1];
+ uchar flags[2];
+ uchar keylen[2];
+ uchar repc[8];
+ uchar nonce[32];
+ uchar eapoliv[16];
+ uchar rsc[8];
+ uchar id[8];
+ uchar mic[16];
+ uchar datalen[2];
+ uchar data[];
+};
+
+int prompt;
+int debug;
+int fd, cfd;
+char *dev;
+char devdir[40];
+uchar ptk[PTKlen];
+char essid[32+1];
+uvlong lastrepc;
+
+uchar rsnie[] = {+ 0x30, /* RSN */
+ 0x14, /* length */
+ 0x01, 0x00, /* version 1 */
+ 0x00, 0x0F, 0xAC, 0x02, /* group cipher suite TKIP */
+ 0x01, 0x00, /* peerwise cipher suite count 1 */
+ 0x00, 0x0F, 0xAC, 0x02, /* peerwise cipher suite TKIP */
+ 0x01, 0x00, /* authentication suite count 1 */
+ 0x00, 0x0F, 0xAC, 0x02, /* authentication suite PSK */
+ 0x00, 0x00, /* capabilities */
+};
+
+uchar wpaie[] = {+ 0xdd, /* vendor specific */
+ 0x16, /* length */
+ 0x00, 0x50, 0xf2, 0x01, /* WPAIE type 1 */
+ 0x01, 0x00, /* version 1 */
+ 0x00, 0x50, 0xf2, 0x02, /* group cipher suite TKIP */
+ 0x01, 0x00, /* peerwise cipher suite count 1 */
+ 0x00, 0x50, 0xf2, 0x02, /* peerwise cipher suite TKIP */
+ 0x01, 0x00, /* authentication suite count 1 */
+ 0x00, 0x50, 0xf2, 0x02, /* authentication suite PSK */
+};
+
+/* only WPA for now */
+uchar *rsne = wpaie;
+int rsnelen = sizeof(wpaie);
+
+char*
+getessid(void)
+{+ char buf[8*1024], *f[2], *p, *e;
+ int fd, n;
+
+ snprint(buf, sizeof(buf), "%s/ifstats", devdir);
+ if((fd = open(buf, OREAD)) < 0)
+ return nil;
+ n = read(fd, buf, sizeof(buf)-1);
+ close(fd);
+ if(n > 0){+ buf[n] = 0;
+ for(p = buf; (e = strchr(p, '\n')) != nil; p = e){+ *e++ = 0;
+ if(tokenize(p, f, 2) != 2)
+ continue;
+ if(strcmp(f[0], "essid:") != 0)
+ continue;
+ strncpy(essid, f[1], 32);
+ return essid;
+ }
+ }
+ return nil;
+}
+
+int
+getptk( uchar smac[Eaddrlen], uchar amac[Eaddrlen],
+ uchar snonce[Noncelen], uchar anonce[Noncelen],
+ uchar ptk[PTKlen])
+{+ uchar buf[2*Eaddrlen + 2*Noncelen], *p;
+ AuthRpc *rpc;
+ int afd, ret;
+ char *s;
+
+ ret = -1;
+ s = nil;
+ rpc = nil;
+ if((afd = open("/mnt/factotum/rpc", ORDWR)) < 0)+ goto out;
+ if((rpc = auth_allocrpc(afd)) == nil)
+ goto out;
+ if((s = getessid()) == nil)
+ goto out;
+ if((s = smprint("proto=wpapsk role=client essid=%q", s)) == nil)+ goto out;
+ if((ret = auth_rpc(rpc, "start", s, strlen(s))) != ARok)
+ goto out;
+ p = buf;
+ memmove(p, smac, Eaddrlen); p += Eaddrlen;
+ memmove(p, amac, Eaddrlen); p += Eaddrlen;
+ memmove(p, snonce, Noncelen); p += Noncelen;
+ memmove(p, anonce, Noncelen); p += Noncelen;
+ if((ret = auth_rpc(rpc, "write", buf, p - buf)) != ARok)
+ goto out;
+ if((ret = auth_rpc(rpc, "read", nil, 0)) != ARok)
+ goto out;
+ if(rpc->narg != PTKlen)
+ goto out;
+ memmove(ptk, rpc->arg, PTKlen);
+ ret = 0;
+out:
+ free(s);
+ if(afd >= 0) close(afd);
+ if(rpc != nil) auth_freerpc(rpc);
+ return ret;
+}
+
+int
+Hfmt(Fmt *f)
+{+ uchar *p, *e;
+
+ p = va_arg(f->args, uchar*);
+ e = p;
+ if(f->prec >= 0)
+ e += f->prec;
+ for(; p != e; p++)
+ if(fmtprint(f, "%.2x", *p) < 0)
+ return -1;
+ return 0;
+}
+
+void
+dumpkeydescr(Keydescr *kd)
+{+ static struct {+ int flag;
+ char *name;
+ } flags[] = {+ Fptk, "ptk",
+ Fins, "ins",
+ Fack, "ack",
+ Fmic, "mic",
+ Fsec, "sec",
+ Ferr, "err",
+ Freq, "req",
+ Fenc, "enc",
+ };
+ int i, f;
+
+ f = kd->flags[0]<<8 | kd->flags[1];
+ fprint(2, "type=%.*H flags=%.*H ( ",
+ sizeof(kd->type), kd->type,
+ sizeof(kd->flags), kd->flags);
+ for(i=0; i<nelem(flags); i++)
+ if(flags[i].flag & f)
+ fprint(2, "%s ", flags[i].name);
+ fprint(2, ") len=%.*H\nrepc=%.*H nonce=%.*H\neapoliv=%.*H rsc=%.*H id=%.*H mic=%.*H\n",
+ sizeof(kd->keylen), kd->keylen,
+ sizeof(kd->repc), kd->repc,
+ sizeof(kd->nonce), kd->nonce,
+ sizeof(kd->eapoliv), kd->eapoliv,
+ sizeof(kd->rsc), kd->rsc,
+ sizeof(kd->id), kd->id,
+ sizeof(kd->mic), kd->mic);
+ i = kd->datalen[0]<<8 | kd->datalen[1];
+ fprint(2, "data[%.4x]=%.*H\n\n", i, i, kd->data);
+}
+
+void
+reply(uchar smac[Eaddrlen], uchar amac[Eaddrlen], int flags, Keydescr *kd, uchar *data, int datalen)
+{+ uchar buf[4096], mic[MD5dlen], *m, *p = buf;
+
+ memmove(p, amac, Eaddrlen); p += Eaddrlen;
+ memmove(p, smac, Eaddrlen); p += Eaddrlen;
+ *p++ = 0x88;
+ *p++ = 0x8e;
+
+ m = p;
+ *p++ = 0x01;
+ *p++ = 0x03;
+ datalen += Keydescrlen;
+ *p++ = datalen >> 8;
+ *p++ = datalen;
+ datalen -= Keydescrlen;
+
+ memmove(p, kd, Keydescrlen);
+ kd = (Keydescr*)p;
+ kd->flags[0] = flags >> 8;
+ kd->flags[1] = flags;
+ kd->datalen[0] = datalen >> 8;
+ kd->datalen[1] = datalen;
+ p = kd->data;
+ memmove(p, data, datalen);
+ p += datalen;
+
+ memset(kd->mic, 0, sizeof(kd->mic));
+ if(flags & Fmic){+ hmac_md5(m, p - m, ptk, 16, mic, nil);
+ memmove(kd->mic, mic, sizeof(kd->mic));
+ }
+ if(debug != 0){+ fprint(2, "reply %E -> %E: ", smac, amac);
+ dumpkeydescr(kd);
+ }
+ datalen = p - buf;
+ if(write(fd, buf, datalen) != datalen)
+ sysfatal("write: %r");+}
+
+void
+usage(void)
+{+ fprint(2, "%s: [-dp] [-s essid] dev\n", argv0);
+ exits("usage");+}
+
+void
+main(int argc, char *argv[])
+{+ uchar mac[Eaddrlen], buf[1024];
+ char addr[128];
+ int n;
+
+ quotefmtinstall();
+ fmtinstall('H', Hfmt);+ fmtinstall('E', eipfmt);+
+ ARGBEGIN {+ case 'd':
+ debug = 1;
+ break;
+ case 'p':
+ prompt = 1;
+ break;
+ case 's':
+ strncpy(essid, EARGF(usage()), 32);
+ break;
+ default:
+ usage();
+ } ARGEND;
+
+ if(*argv != nil)
+ dev = *argv++;
+
+ if(*argv != nil || dev == nil)
+ usage();
+
+ if(myetheraddr(mac, dev) < 0)
+ sysfatal("can't get mac address: %r");+
+ snprint(addr, sizeof(addr), "%s!0x888e", dev);
+ if((fd = dial(addr, nil, devdir, &cfd)) < 0)
+ sysfatal("dial: %r");+
+ if(essid[0] != 0)
+ if(fprint(cfd, "essid %s", essid) < 0)
+ sysfatal("write essid: %r");+
+ if(prompt){+ char *s;
+
+ if(essid[0] == 0)
+ getessid();
+ if(essid[0] != 0)
+ s = smprint("proto=wpapsk essid=%q !password?", essid);+ else
+ s = smprint("proto=wpapsk essid? !password?");+ auth_getkey(s);
+ free(s);
+ }
+
+ /*
+ * we use write() instead of fprint so message gets written
+ * at once and not chunked up on fprint buffer.
+ */
+ n = sprint((char*)buf, "auth %.*H", rsnelen, rsne);
+ if(write(cfd, buf, n) != n)
+ sysfatal("write auth: %r");+
+ if(!debug){+ switch(rfork(RFFDG|RFREND|RFPROC|RFNOWAIT)){+ default:
+ exits(nil);
+ case -1:
+ sysfatal("fork: %r");+ return;
+ case 0:
+ break;
+ }
+ }
+
+ for(;;){+ uchar smac[Eaddrlen], amac[Eaddrlen], snonce[Noncelen], anonce[Noncelen], *p, *e, *m;
+ int proto, flags, kid;
+ uvlong repc, rsc;
+ Keydescr *kd;
+
+ if((n = read(fd, buf, sizeof(buf))) < 0)
+ sysfatal("read: %r");+ p = buf;
+ e = buf+n;
+ if(n < 2*Eaddrlen + 2)
+ continue;
+ memmove(smac, p, Eaddrlen); p += Eaddrlen;
+ memmove(amac, p, Eaddrlen); p += Eaddrlen;
+ proto = p[0]<<8 | p[1]; p += 2;
+ if(proto != 0x888e || memcmp(smac, mac, Eaddrlen) != 0)
+ continue;
+
+ m = p;
+ n = e - p;
+ if(n < 4 || p[0] != 0x01 || p[1] != 0x03)
+ continue;
+ n = p[2]<<8 | p[3];
+ p += 4;
+ if(n < Keydescrlen || p + n > e)
+ continue;
+ kd = (Keydescr*)p;
+ if(debug){+ fprint(2, "recv %E <- %E: ", smac, amac);
+ dumpkeydescr(kd);
+ }
+
+ /* only WPA, RSN descriptor format not suppoted yet */
+ if(kd->type[0] != 0xFE)
+ continue;
+
+ flags = kd->flags[0]<<8 | kd->flags[1];
+
+ rsc = (uvlong)kd->rsc[0] |
+ (uvlong)kd->rsc[1]<<8 |
+ (uvlong)kd->rsc[2]<<16 |
+ (uvlong)kd->rsc[3]<<24 |
+ (uvlong)kd->rsc[4]<<32 |
+ (uvlong)kd->rsc[5]<<40;
+
+ repc = (uvlong)kd->repc[7] |
+ (uvlong)kd->repc[6]<<8 |
+ (uvlong)kd->repc[5]<<16 |
+ (uvlong)kd->repc[4]<<24 |
+ (uvlong)kd->repc[3]<<32 |
+ (uvlong)kd->repc[2]<<40 |
+ (uvlong)kd->repc[1]<<48 |
+ (uvlong)kd->repc[0]<<56;
+
+ if(repc <= lastrepc)
+ continue;
+
+ if((flags & Fmic) == 0){+ if((flags & (Fptk|Fack)) != (Fptk|Fack))
+ continue;
+
+ memmove(anonce, kd->nonce, sizeof(anonce));
+ genrandom(snonce, sizeof(snonce));
+ if(getptk(smac, amac, snonce, anonce, ptk) < 0)
+ continue;
+
+ /* ack key exchange with mic */
+ memset(kd->rsc, 0, sizeof(kd->rsc));
+ memset(kd->eapoliv, 0, sizeof(kd->eapoliv));
+ memmove(kd->nonce, snonce, sizeof(kd->nonce));
+ reply(smac, amac, (flags & ~(Fack|Fins)) | Fmic, kd, rsne, rsnelen);
+ } else {+ uchar tmp[MD5dlen], mic[MD5dlen];
+
+ /* check mic */
+ memmove(tmp, kd->mic, sizeof(mic));
+ memset(kd->mic, 0, sizeof(kd->mic));
+ hmac_md5(m, e - m, ptk, 16, mic, nil);
+ if(memcmp(tmp, mic, sizeof(mic)) != 0)
+ continue;
+
+ lastrepc = repc;
+
+ if((flags & (Fptk|Fsec|Fack)) == (Fptk|Fack)){+ /* install peerwise receive key */
+ if(fprint(cfd, "rxkey %.*H tkip:%.*H@%llux", Eaddrlen, amac, 32, ptk+32, rsc) < 0)
+ sysfatal("write rxkey: %r");+
+ /* pick random 16bit tsc value for transmit */
+ rsc = 1 + (truerand() & 0x7fff);
+ memset(kd->rsc, 0, sizeof(kd->rsc));
+ kd->rsc[0] = rsc;
+ kd->rsc[1] = rsc>>8;
+ memset(kd->eapoliv, 0, sizeof(kd->eapoliv));
+ memset(kd->nonce, 0, sizeof(kd->nonce));
+ reply(smac, amac, flags & ~Fack, kd, nil, 0);
+ sleep(100);
+
+ /* install peerwise transmit key */
+ if(fprint(cfd, "txkey %.*H tkip:%.*H@%llux", Eaddrlen, amac, 32, ptk+32, rsc) < 0)
+ sysfatal("write txkey: %r");+ } else
+ if((flags & (Fptk|Fsec|Fack)) == (Fsec|Fack)){+ uchar seed[32], gtk[GTKlen];
+ RC4state rs;
+ int len;
+
+ len = kd->datalen[1]<<8 | kd->datalen[0];
+ if(len > sizeof(gtk))
+ len = sizeof(gtk);
+ memmove(gtk, kd->data, len);
+ memmove(seed, kd->eapoliv, 16);
+ memmove(seed+16, ptk+16, 16);
+ setupRC4state(&rs, seed, sizeof(seed));
+ rc4skip(&rs, 256);
+ rc4(&rs, gtk, len);
+
+ /* install group key */
+ kid = (flags >> 4) & 3;
+ if(fprint(cfd, "rxkey%d %.*H tkip:%.*H@%llux", kid, Eaddrlen, amac, len, gtk, rsc) < 0)
+ sysfatal("write rxkey%d: %r", kid);+
+ memset(kd->rsc, 0, sizeof(kd->rsc));
+ memset(kd->eapoliv, 0, sizeof(kd->eapoliv));
+ memset(kd->nonce, 0, sizeof(kd->nonce));
+ reply(smac, amac, flags & ~Fack, kd, nil, 0);
+ }
+ }
+ }
+}
--
⑨