bug fixes; add secstore

This commit is contained in:
rsc 2005-02-11 16:56:15 +00:00
parent 3889d01d4b
commit 2e397eb47c
8 changed files with 698 additions and 111 deletions

View file

@ -419,7 +419,7 @@ fsflush(Req *r)
static void static void
fsdestroyfid(Fid *fid) fsdestroyfid(Fid *fid)
{ {
if(fid->qid.path == Qrpc){ if(fid->qid.path == Qrpc && fid->aux){
convhangup(fid->aux); convhangup(fid->aux);
convclose(fid->aux); convclose(fid->aux);
} }
@ -435,8 +435,6 @@ fsreqthread(void *v)
USED(v); USED(v);
creq = chancreate(sizeof(Req*), 0);
while((r = recvp(creq)) != nil){ while((r = recvp(creq)) != nil){
switch(r->ifcall.type){ switch(r->ifcall.type){
default: default:
@ -464,8 +462,6 @@ fsclunkthread(void *v)
Fid *f; Fid *f;
USED(v); USED(v);
cfid = chancreate(sizeof(Fid*), 0);
cfidr = chancreate(sizeof(Fid*), 0);
while((f = recvp(cfid)) != nil){ while((f = recvp(cfid)) != nil){
fsdestroyfid(f); fsdestroyfid(f);
@ -486,13 +482,6 @@ fsproc(void *v)
static void static void
fsattach(Req *r) fsattach(Req *r)
{ {
static int first = 1;
if(first){
proccreate(fsproc, nil, STACK);
first = 0;
}
r->fid->qid = mkqid(QTDIR, Qroot); r->fid->qid = mkqid(QTDIR, Qroot);
r->ofcall.qid = r->fid->qid; r->ofcall.qid = r->fid->qid;
respond(r, nil); respond(r, nil);
@ -511,6 +500,17 @@ fssendclunk(Fid *f)
recvp(cfidr); recvp(cfidr);
} }
void
fsstart(Srv *s)
{
USED(s);
creq = chancreate(sizeof(Req*), 0);
cfid = chancreate(sizeof(Fid*), 0);
cfidr = chancreate(sizeof(Fid*), 0);
proccreate(fsproc, nil, STACK);
}
Srv fs = { Srv fs = {
.attach= fsattach, .attach= fsattach,
.walk1= fswalk1, .walk1= fswalk1,
@ -520,5 +520,6 @@ Srv fs = {
.stat= fsstat, .stat= fsstat,
.flush= fssend, .flush= fssend,
.destroyfid= fssendclunk, .destroyfid= fssendclunk,
.start= fsstart,
}; };

View file

@ -2,8 +2,9 @@
#include "dat.h" #include "dat.h"
int debug; int debug;
int trysecstore = 1;
char *factname = "factotum"; char *factname = "factotum";
char *service = nil; char *service = "factotum";
char *owner; char *owner;
char *authaddr; char *authaddr;
void gflag(char*); void gflag(char*);
@ -11,18 +12,20 @@ void gflag(char*);
void void
usage(void) usage(void)
{ {
fprint(2, "usage: factotum [-Dd] [-a authaddr] [-m mtpt]\n"); fprint(2, "usage: factotum [-Dd] [-a authaddr] [-m mtpt] [-s service]\n");
fprint(2, " or factotum -g keypattern\n"); fprint(2, " or factotum -g keypattern\n");
fprint(2, " or factotum -g 'badkeyattr\nmsg\nkeypattern'"); fprint(2, " or factotum -g 'badkeyattr\\nmsg\\nkeypattern'\n");
exits("usage"); threadexitsall("usage");
} }
void void
threadmain(int argc, char *argv[]) threadmain(int argc, char *argv[])
{ {
char *mtpt; char *mtpt;
char err[ERRMAX];
mtpt = "/mnt"; // mtpt = "/mnt";
mtpt = nil;
owner = getuser(); owner = getuser();
quotefmtinstall(); quotefmtinstall();
fmtinstall('A', attrfmt); fmtinstall('A', attrfmt);
@ -31,7 +34,7 @@ threadmain(int argc, char *argv[])
if(argc == 3 && strcmp(argv[1], "-g") == 0){ if(argc == 3 && strcmp(argv[1], "-g") == 0){
gflag(argv[2]); gflag(argv[2]);
exits(nil); threadexitsall(nil);
} }
ARGBEGIN{ ARGBEGIN{
@ -51,11 +54,24 @@ threadmain(int argc, char *argv[])
case 's': case 's':
service = EARGF(usage()); service = EARGF(usage());
break; break;
case 'n':
trysecstore = 0;
break;
}ARGEND }ARGEND
if(argc != 0) if(argc != 0)
usage(); usage();
if(trysecstore && havesecstore()){
while(secstorefetch() < 0){
rerrstr(err, sizeof err);
if(strcmp(err, "cancel") == 0)
break;
fprint(2, "secstorefetch: %r\n");
fprint(2, "Enter an empty password to quit.\n");
}
}
threadpostmountsrv(&fs, service, mtpt, MBEFORE); threadpostmountsrv(&fs, service, mtpt, MBEFORE);
threadexits(nil); threadexits(nil);
} }
@ -150,14 +166,14 @@ gflag(char *s)
if(nf == 1){ /* needkey or old badkey */ if(nf == 1){ /* needkey or old badkey */
fprint(fd, "\n"); fprint(fd, "\n");
askuser(fd, s); askuser(fd, s);
exits(nil); threadexitsall(nil);
} }
if(nf == 3){ /* new badkey */ if(nf == 3){ /* new badkey */
fprint(fd, "\n"); fprint(fd, "\n");
fprint(fd, "!replace: %s\n", f[0]); fprint(fd, "!replace: %s\n", f[0]);
fprint(fd, "!because: %s\n", f[1]); fprint(fd, "!because: %s\n", f[1]);
askuser(fd, f[2]); askuser(fd, f[2]);
exits(nil); threadexitsall(nil);
} }
usage(); usage();
} }

View file

@ -22,6 +22,7 @@ OFILES=\
rpc.$O\ rpc.$O\
util.$O\ util.$O\
xio.$O\ xio.$O\
secstore.$O\
HFILES=dat.h HFILES=dat.h

View file

@ -119,7 +119,7 @@ out:
static int static int
p9anyclient(Conv *c) p9anyclient(Conv *c)
{ {
char *s, **f, *tok[20], ok[3], *q, *user, *dom; char *s, **f, *tok[20], ok[3], *q, *user, *dom, *choice;
int i, n, ret, version; int i, n, ret, version;
Key *k; Key *k;
Attr *attr; Attr *attr;
@ -222,12 +222,12 @@ found:
c->state = "write choice"; c->state = "write choice";
/* have a key: go for it */ /* have a key: go for it */
s = estrappend(nil, "%q %q", f[i], q); choice = estrappend(nil, "%q %q", f[i], q);
if(convwrite(c, s, strlen(s)+1) < 0){ if(convwrite(c, choice, strlen(choice)+1) < 0){
free(s); free(choice);
goto out; goto out;
} }
free(s); free(choice);
if(version == 2){ if(version == 2){
c->state = "read ok"; c->state = "read ok";

View file

@ -15,7 +15,7 @@ memrandom(void *p, int n)
/* /*
* create a change uid capability * create a change uid capability
*/ */
static int caphashfd; static int caphashfd = -1;
static char* static char*
mkcap(char *from, char *to) mkcap(char *from, char *to)
@ -84,17 +84,7 @@ bindnetcs(void)
int int
_authdial(char *net, char *authdom) _authdial(char *net, char *authdom)
{ {
int vanilla; return authdial(net, authdom);
vanilla = net==nil || strcmp(net, "/net")==0;
if(!vanilla || bindnetcs()>=0)
return authdial(net, authdom);
/* use the auth sever passed to us as an arg */
if(authaddr == nil)
return -1;
return dial(netmkaddr(authaddr, "tcp", "567"), 0, 0, 0);
} }
Key* Key*
@ -116,74 +106,3 @@ plan9authkey(Attr *a)
werrstr("could not find plan 9 auth key dom %q", dom); werrstr("could not find plan 9 auth key dom %q", dom);
return k; return k;
} }
/*
* prompt for a string with a possible default response
*/
char*
readcons(char *prompt, char *def, int raw)
{
int fdin, fdout, ctl, n;
char line[10];
char *s;
fdin = open("/dev/cons", OREAD);
if(fdin < 0)
fdin = 0;
fdout = open("/dev/cons", OWRITE);
if(fdout < 0)
fdout = 1;
if(def != nil)
fprint(fdout, "%s[%s]: ", prompt, def);
else
fprint(fdout, "%s: ", prompt);
if(raw){
ctl = open("/dev/consctl", OWRITE);
if(ctl >= 0)
write(ctl, "rawon", 5);
} else
ctl = -1;
s = estrdup("");
for(;;){
n = read(fdin, line, 1);
if(n == 0){
Error:
close(fdin);
close(fdout);
if(ctl >= 0)
close(ctl);
free(s);
return nil;
}
if(n < 0)
goto Error;
if(line[0] == 0x7f)
goto Error;
if(n == 0 || line[0] == '\n' || line[0] == '\r'){
if(raw){
write(ctl, "rawoff", 6);
write(fdout, "\n", 1);
}
close(ctl);
close(fdin);
close(fdout);
if(*s == 0 && def != nil)
s = estrappend(s, "%s", def);
return s;
}
if(line[0] == '\b'){
if(strlen(s) > 0)
s[strlen(s)-1] = 0;
} else if(line[0] == 0x15) { /* ^U: line kill */
if(def != nil)
fprint(fdout, "\n%s[%s]: ", prompt, def);
else
fprint(fdout, "\n%s: ", prompt);
s[0] = 0;
} else {
s = estrappend(s, "%c", line[0]);
}
}
return nil; /* not reached */
}

648
src/cmd/factotum/secstore.c Normal file
View file

@ -0,0 +1,648 @@
/*
* Various files from /sys/src/cmd/auth/secstore, just enough
* to download a file at boot time.
*/
#include "std.h"
#include "dat.h"
#include <ip.h>
enum{ CHK = 16};
enum{ MAXFILESIZE = 10*1024*1024 };
enum{// PW status bits
Enabled = (1<<0),
STA = (1<<1), // extra SecurID step
};
static char testmess[] = "__secstore\tPAK\nC=%s\nm=0\n";
char *secstore;
int
secdial(void)
{
char *p;
int fd;
p = secstore;
if(p == nil) /* else use the authserver */
p = getenv("secstore");
if(p == nil)
p = getenv("auth");
if(p == nil)
p = "secstore";
fd = dial(netmkaddr(p, "net", "secstore"), 0, 0, 0);
if(fd < 0)
fprint(2, "secdial: %r\n");
return fd;
}
int
havesecstore(void)
{
int m, n, fd;
uchar buf[500];
n = snprint((char*)buf, sizeof buf, testmess, owner);
hnputs(buf, 0x8000+n-2);
fd = secdial();
if(fd < 0)
return 0;
if(write(fd, buf, n) != n || readn(fd, buf, 2) != 2){
close(fd);
return 0;
}
n = ((buf[0]&0x7f)<<8) + buf[1];
if(n+1 > sizeof buf){
werrstr("implausibly large count %d", n);
close(fd);
return 0;
}
m = readn(fd, buf, n);
close(fd);
if(m != n){
if(m >= 0)
werrstr("short read from secstore");
return 0;
}
buf[n] = 0;
if(strcmp((char*)buf, "!account expired") == 0){
werrstr("account expired");
return 0;
}
return strcmp((char*)buf, "!account exists") == 0;
}
// delimited, authenticated, encrypted connection
enum{ Maxmsg=4096 }; // messages > Maxmsg bytes are truncated
typedef struct SConn SConn;
extern SConn* newSConn(int); // arg is open file descriptor
struct SConn{
void *chan;
int secretlen;
int (*secret)(SConn*, uchar*, int);//
int (*read)(SConn*, uchar*, int); // <0 if error; errmess in buffer
int (*write)(SConn*, uchar*, int);
void (*free)(SConn*); // also closes file descriptor
};
// secret(s,b,dir) sets secret for digest, encrypt, using the secretlen
// bytes in b to form keys for the two directions;
// set dir=0 in client, dir=1 in server
// error convention: write !message in-band
#define readstr secstore_readstr
static void writerr(SConn*, char*);
static int readstr(SConn*, char*); // call with buf of size Maxmsg+1
// returns -1 upon error, with error message in buf
typedef struct ConnState {
uchar secret[SHA1dlen];
ulong seqno;
RC4state rc4;
} ConnState;
typedef struct SS{
int fd; // file descriptor for read/write of encrypted data
int alg; // if nonzero, "alg sha rc4_128"
ConnState in, out;
} SS;
static int
SC_secret(SConn *conn, uchar *sigma, int direction)
{
SS *ss = (SS*)(conn->chan);
int nsigma = conn->secretlen;
if(direction != 0){
hmac_sha1(sigma, nsigma, (uchar*)"one", 3, ss->out.secret, nil);
hmac_sha1(sigma, nsigma, (uchar*)"two", 3, ss->in.secret, nil);
}else{
hmac_sha1(sigma, nsigma, (uchar*)"two", 3, ss->out.secret, nil);
hmac_sha1(sigma, nsigma, (uchar*)"one", 3, ss->in.secret, nil);
}
setupRC4state(&ss->in.rc4, ss->in.secret, 16); // restrict to 128 bits
setupRC4state(&ss->out.rc4, ss->out.secret, 16);
ss->alg = 1;
return 0;
}
static void
hash(uchar secret[SHA1dlen], uchar *data, int len, int seqno, uchar d[SHA1dlen])
{
DigestState sha;
uchar seq[4];
seq[0] = seqno>>24;
seq[1] = seqno>>16;
seq[2] = seqno>>8;
seq[3] = seqno;
memset(&sha, 0, sizeof sha);
sha1(secret, SHA1dlen, nil, &sha);
sha1(data, len, nil, &sha);
sha1(seq, 4, d, &sha);
}
static int
verify(uchar secret[SHA1dlen], uchar *data, int len, int seqno, uchar d[SHA1dlen])
{
DigestState sha;
uchar seq[4];
uchar digest[SHA1dlen];
seq[0] = seqno>>24;
seq[1] = seqno>>16;
seq[2] = seqno>>8;
seq[3] = seqno;
memset(&sha, 0, sizeof sha);
sha1(secret, SHA1dlen, nil, &sha);
sha1(data, len, nil, &sha);
sha1(seq, 4, digest, &sha);
return memcmp(d, digest, SHA1dlen);
}
static int
SC_read(SConn *conn, uchar *buf, int n)
{
SS *ss = (SS*)(conn->chan);
uchar count[2], digest[SHA1dlen];
int len, nr;
if(read(ss->fd, count, 2) != 2 || count[0]&0x80 == 0){
werrstr("!SC_read invalid count");
return -1;
}
len = (count[0]&0x7f)<<8 | count[1]; // SSL-style count; no pad
if(ss->alg){
len -= SHA1dlen;
if(len <= 0 || readn(ss->fd, digest, SHA1dlen) != SHA1dlen){
werrstr("!SC_read missing sha1");
return -1;
}
if(len > n || readn(ss->fd, buf, len) != len){
werrstr("!SC_read missing data");
return -1;
}
rc4(&ss->in.rc4, digest, SHA1dlen);
rc4(&ss->in.rc4, buf, len);
if(verify(ss->in.secret, buf, len, ss->in.seqno, digest) != 0){
werrstr("!SC_read integrity check failed");
return -1;
}
}else{
if(len <= 0 || len > n){
werrstr("!SC_read implausible record length");
return -1;
}
if( (nr = readn(ss->fd, buf, len)) != len){
werrstr("!SC_read expected %d bytes, but got %d", len, nr);
return -1;
}
}
ss->in.seqno++;
return len;
}
static int
SC_write(SConn *conn, uchar *buf, int n)
{
SS *ss = (SS*)(conn->chan);
uchar count[2], digest[SHA1dlen], enc[Maxmsg+1];
int len;
if(n <= 0 || n > Maxmsg+1){
werrstr("!SC_write invalid n %d", n);
return -1;
}
len = n;
if(ss->alg)
len += SHA1dlen;
count[0] = 0x80 | len>>8;
count[1] = len;
if(write(ss->fd, count, 2) != 2){
werrstr("!SC_write invalid count");
return -1;
}
if(ss->alg){
hash(ss->out.secret, buf, n, ss->out.seqno, digest);
rc4(&ss->out.rc4, digest, SHA1dlen);
memcpy(enc, buf, n);
rc4(&ss->out.rc4, enc, n);
if(write(ss->fd, digest, SHA1dlen) != SHA1dlen ||
write(ss->fd, enc, n) != n){
werrstr("!SC_write error on send");
return -1;
}
}else{
if(write(ss->fd, buf, n) != n){
werrstr("!SC_write error on send");
return -1;
}
}
ss->out.seqno++;
return n;
}
static void
SC_free(SConn *conn)
{
SS *ss = (SS*)(conn->chan);
close(ss->fd);
free(ss);
free(conn);
}
SConn*
newSConn(int fd)
{
SS *ss;
SConn *conn;
if(fd < 0)
return nil;
ss = (SS*)emalloc(sizeof(*ss));
conn = (SConn*)emalloc(sizeof(*conn));
ss->fd = fd;
ss->alg = 0;
conn->chan = (void*)ss;
conn->secretlen = SHA1dlen;
conn->free = SC_free;
conn->secret = SC_secret;
conn->read = SC_read;
conn->write = SC_write;
return conn;
}
static void
writerr(SConn *conn, char *s)
{
char buf[Maxmsg];
snprint(buf, Maxmsg, "!%s", s);
conn->write(conn, (uchar*)buf, strlen(buf));
}
static int
readstr(SConn *conn, char *s)
{
int n;
n = conn->read(conn, (uchar*)s, Maxmsg);
if(n >= 0){
s[n] = 0;
if(s[0] == '!'){
memmove(s, s+1, n);
n = -1;
}
}else{
strcpy(s, "read error");
}
return n;
}
static int
getfile(SConn *conn, uchar *key, int nkey)
{
char *buf;
int nbuf, n, nr, len;
char s[Maxmsg+1], *gf, *p, *q;
uchar skey[SHA1dlen], ib[Maxmsg+CHK], *ibr, *ibw;
AESstate aes;
DigestState *sha;
gf = "factotum";
memset(&aes, 0, sizeof aes);
snprint(s, Maxmsg, "GET %s\n", gf);
conn->write(conn, (uchar*)s, strlen(s));
/* get file size */
s[0] = '\0';
if(readstr(conn, s) < 0){
werrstr("secstore: %r");
return -1;
}
if((len = atoi(s)) < 0){
werrstr("secstore: remote file %s does not exist", gf);
return -1;
}else if(len > MAXFILESIZE){//assert
werrstr("secstore: implausible file size %d for %s", len, gf);
return -1;
}
ibr = ibw = ib;
buf = nil;
nbuf = 0;
for(nr=0; nr < len;){
if((n = conn->read(conn, ibw, Maxmsg)) <= 0){
werrstr("secstore: empty file chunk n=%d nr=%d len=%d: %r", n, nr, len);
return -1;
}
nr += n;
ibw += n;
if(!aes.setup){ /* first time, read 16 byte IV */
if(n < 16){
werrstr("secstore: no IV in file");
return -1;
}
sha = sha1((uchar*)"aescbc file", 11, nil, nil);
sha1(key, nkey, skey, sha);
setupAESstate(&aes, skey, AESbsize, ibr);
memset(skey, 0, sizeof skey);
ibr += AESbsize;
n -= AESbsize;
}
aesCBCdecrypt(ibw-n, n, &aes);
n = ibw-ibr-CHK;
if(n > 0){
buf = erealloc(buf, nbuf+n+1);
memmove(buf+nbuf, ibr, n);
nbuf += n;
ibr += n;
}
memmove(ib, ibr, ibw-ibr);
ibw = ib + (ibw-ibr);
ibr = ib;
}
n = ibw-ibr;
if((n != CHK) || (memcmp(ib, "XXXXXXXXXXXXXXXX", CHK) != 0)){
werrstr("secstore: decrypted file failed to authenticate!");
free(buf);
return -1;
}
if(nbuf == 0){
werrstr("secstore got empty file");
return -1;
}
buf[nbuf] = '\0';
p = buf;
n = 0;
while(p){
if(q = strchr(p, '\n'))
*q++ = '\0';
n++;
if(ctlwrite(p) < 0)
fprint(2, "secstore(%s) line %d: %r\n", gf, n);
p = q;
}
free(buf);
return 0;
}
static char VERSION[] = "secstore";
typedef struct PAKparams{
mpint *q, *p, *r, *g;
} PAKparams;
static PAKparams *pak;
// This group was generated by the seed EB7B6E35F7CD37B511D96C67D6688CC4DD440E1E.
static void
initPAKparams(void)
{
if(pak)
return;
pak = (PAKparams*)emalloc(sizeof(*pak));
pak->q = strtomp("E0F0EF284E10796C5A2A511E94748BA03C795C13", nil, 16, nil);
pak->p = strtomp("C41CFBE4D4846F67A3DF7DE9921A49D3B42DC33728427AB159CEC8CBBD"
"B12B5F0C244F1A734AEB9840804EA3C25036AD1B61AFF3ABBC247CD4B384224567A86"
"3A6F020E7EE9795554BCD08ABAD7321AF27E1E92E3DB1C6E7E94FAAE590AE9C48F96D9"
"3D178E809401ABE8A534A1EC44359733475A36A70C7B425125062B1142D", nil, 16, nil);
pak->r = strtomp("DF310F4E54A5FEC5D86D3E14863921E834113E060F90052AD332B3241CEF"
"2497EFA0303D6344F7C819691A0F9C4A773815AF8EAECFB7EC1D98F039F17A32A7E887"
"D97251A927D093F44A55577F4D70444AEBD06B9B45695EC23962B175F266895C67D21"
"C4656848614D888A4", nil, 16, nil);
pak->g = strtomp("2F1C308DC46B9A44B52DF7DACCE1208CCEF72F69C743ADD4D2327173444"
"ED6E65E074694246E07F9FD4AE26E0FDDD9F54F813C40CB9BCD4338EA6F242AB94CD41"
"0E676C290368A16B1A3594877437E516C53A6EEE5493A038A017E955E218E7819734E3E"
"2A6E0BAE08B14258F8C03CC1B30E0DDADFCF7CEDF0727684D3D255F1", nil, 16, nil);
}
// H = (sha(ver,C,sha(passphrase)))^r mod p,
// a hash function expensive to attack by brute force.
static void
longhash(char *ver, char *C, uchar *passwd, mpint *H)
{
uchar *Cp;
int i, n, nver, nC;
uchar buf[140], key[1];
nver = strlen(ver);
nC = strlen(C);
n = nver + nC + SHA1dlen;
Cp = (uchar*)emalloc(n);
memmove(Cp, ver, nver);
memmove(Cp+nver, C, nC);
memmove(Cp+nver+nC, passwd, SHA1dlen);
for(i = 0; i < 7; i++){
key[0] = 'A'+i;
hmac_sha1(Cp, n, key, sizeof key, buf+i*SHA1dlen, nil);
}
memset(Cp, 0, n);
free(Cp);
betomp(buf, sizeof buf, H);
mpmod(H, pak->p, H);
mpexp(H, pak->r, pak->p, H);
}
// Hi = H^-1 mod p
static char *
PAK_Hi(char *C, char *passphrase, mpint *H, mpint *Hi)
{
uchar passhash[SHA1dlen];
sha1((uchar *)passphrase, strlen(passphrase), passhash, nil);
initPAKparams();
longhash(VERSION, C, passhash, H);
mpinvert(H, pak->p, Hi);
return mptoa(Hi, 64, nil, 0);
}
// another, faster, hash function for each party to
// confirm that the other has the right secrets.
static void
shorthash(char *mess, char *C, char *S, char *m, char *mu, char *sigma, char *Hi, uchar *digest)
{
SHA1state *state;
state = sha1((uchar*)mess, strlen(mess), 0, 0);
state = sha1((uchar*)C, strlen(C), 0, state);
state = sha1((uchar*)S, strlen(S), 0, state);
state = sha1((uchar*)m, strlen(m), 0, state);
state = sha1((uchar*)mu, strlen(mu), 0, state);
state = sha1((uchar*)sigma, strlen(sigma), 0, state);
state = sha1((uchar*)Hi, strlen(Hi), 0, state);
state = sha1((uchar*)mess, strlen(mess), 0, state);
state = sha1((uchar*)C, strlen(C), 0, state);
state = sha1((uchar*)S, strlen(S), 0, state);
state = sha1((uchar*)m, strlen(m), 0, state);
state = sha1((uchar*)mu, strlen(mu), 0, state);
state = sha1((uchar*)sigma, strlen(sigma), 0, state);
sha1((uchar*)Hi, strlen(Hi), digest, state);
}
// On input, conn provides an open channel to the server;
// C is the name this client calls itself;
// pass is the user's passphrase
// On output, session secret has been set in conn
// (unless return code is negative, which means failure).
// If pS is not nil, it is set to the (alloc'd) name the server calls itself.
static int
PAKclient(SConn *conn, char *C, char *pass, char **pS)
{
char *mess, *mess2, *eol, *S, *hexmu, *ks, *hexm, *hexsigma = nil, *hexHi;
char kc[2*SHA1dlen+1];
uchar digest[SHA1dlen];
int rc = -1, n;
mpint *x, *m = mpnew(0), *mu = mpnew(0), *sigma = mpnew(0);
mpint *H = mpnew(0), *Hi = mpnew(0);
hexHi = PAK_Hi(C, pass, H, Hi);
// random 1<=x<=q-1; send C, m=g**x H
x = mprand(164, genrandom, nil);
mpmod(x, pak->q, x);
if(mpcmp(x, mpzero) == 0)
mpassign(mpone, x);
mpexp(pak->g, x, pak->p, m);
mpmul(m, H, m);
mpmod(m, pak->p, m);
hexm = mptoa(m, 64, nil, 0);
mess = (char*)emalloc(2*Maxmsg+2);
mess2 = mess+Maxmsg+1;
snprint(mess, Maxmsg, "%s\tPAK\nC=%s\nm=%s\n", VERSION, C, hexm);
conn->write(conn, (uchar*)mess, strlen(mess));
// recv g**y, S, check hash1(g**xy)
if(readstr(conn, mess) < 0){
fprint(2, "error: %s\n", mess);
writerr(conn, "couldn't read g**y");
goto done;
}
eol = strchr(mess, '\n');
if(strncmp("mu=", mess, 3) != 0 || !eol || strncmp("\nk=", eol, 3) != 0){
writerr(conn, "verifier syntax error");
goto done;
}
hexmu = mess+3;
*eol = 0;
ks = eol+3;
eol = strchr(ks, '\n');
if(!eol || strncmp("\nS=", eol, 3) != 0){
writerr(conn, "verifier syntax error for secstore 1.0");
goto done;
}
*eol = 0;
S = eol+3;
eol = strchr(S, '\n');
if(!eol){
writerr(conn, "verifier syntax error for secstore 1.0");
goto done;
}
*eol = 0;
if(pS)
*pS = estrdup(S);
strtomp(hexmu, nil, 64, mu);
mpexp(mu, x, pak->p, sigma);
hexsigma = mptoa(sigma, 64, nil, 0);
shorthash("server", C, S, hexm, hexmu, hexsigma, hexHi, digest);
enc64(kc, sizeof kc, digest, SHA1dlen);
if(strcmp(ks, kc) != 0){
writerr(conn, "verifier didn't match");
goto done;
}
// send hash2(g**xy)
shorthash("client", C, S, hexm, hexmu, hexsigma, hexHi, digest);
enc64(kc, sizeof kc, digest, SHA1dlen);
snprint(mess2, Maxmsg, "k'=%s\n", kc);
conn->write(conn, (uchar*)mess2, strlen(mess2));
// set session key
shorthash("session", C, S, hexm, hexmu, hexsigma, hexHi, digest);
memset(hexsigma, 0, strlen(hexsigma));
n = conn->secret(conn, digest, 0);
memset(digest, 0, SHA1dlen);
if(n < 0){//assert
writerr(conn, "can't set secret");
goto done;
}
rc = 0;
done:
mpfree(x);
mpfree(sigma);
mpfree(mu);
mpfree(m);
mpfree(Hi);
mpfree(H);
free(hexsigma);
free(hexHi);
free(hexm);
free(mess);
return rc;
}
int
secstorefetch(void)
{
int rv = -1, fd;
char s[Maxmsg+1];
SConn *conn;
char *pass, *sta;
sta = nil;
conn = nil;
pass = readcons("secstore password", nil, 1);
if(pass==nil || strlen(pass)==0){
werrstr("cancel");
goto Out;
}
if((fd = secdial()) < 0)
goto Out;
if((conn = newSConn(fd)) == nil)
goto Out;
if(PAKclient(conn, owner, pass, nil) < 0){
werrstr("password mistyped?");
goto Out;
}
if(readstr(conn, s) < 0)
goto Out;
if(strcmp(s, "STA") == 0){
sta = readcons("STA PIN+SecureID", nil, 1);
if(sta==nil || strlen(sta)==0){
werrstr("cancel");
goto Out;
}
if(strlen(sta) >= sizeof s - 3){
werrstr("STA response too long");
goto Out;
}
strcpy(s+3, sta);
conn->write(conn, (uchar*)s, strlen(s));
readstr(conn, s);
}
if(strcmp(s, "OK") !=0){
werrstr("%s", s);
goto Out;
}
if(getfile(conn, (uchar*)pass, strlen(pass)) < 0)
goto Out;
conn->write(conn, (uchar*)"BYE", 3);
rv = 0;
Out:
if(conn)
conn->free(conn);
if(pass)
free(pass);
if(sta)
free(sta);
return rv;
}

View file

@ -36,6 +36,7 @@ char*
estrappend(char *s, char *fmt, ...) estrappend(char *s, char *fmt, ...)
{ {
char *t; char *t;
int l;
va_list arg; va_list arg;
va_start(arg, fmt); va_start(arg, fmt);
@ -43,8 +44,9 @@ estrappend(char *s, char *fmt, ...)
if(t == nil) if(t == nil)
sysfatal("out of memory"); sysfatal("out of memory");
va_end(arg); va_end(arg);
s = erealloc(s, strlen(s)+strlen(t)+1); l = s ? strlen(s) : 0;
strcat(s, t); s = erealloc(s, l+strlen(t)+1);
strcpy(s+l, t);
free(t); free(t);
return s; return s;
} }

View file

@ -87,7 +87,7 @@ _ioauthdial(va_list *arg)
dom = va_arg(*arg, char*); dom = va_arg(*arg, char*);
fd = _authdial(net, dom); fd = _authdial(net, dom);
if(fd < 0) if(fd < 0)
fprint(2, "authdial: %r"); fprint(2, "authdial: %r\n");
return fd; return fd;
} }