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/*
* devtls - record layer for transport layer security 1.0 and secure sockets layer 3.0
*/
#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "../port/error.h"
#include <libsec.h>
typedef struct OneWay OneWay;
typedef struct Secret Secret;
typedef struct TlsRec TlsRec;
typedef struct TlsErrs TlsErrs;
enum {
Statlen= 1024, /* max. length of status or stats message */
/* buffer limits */
MaxRecLen = 1<<14, /* max payload length of a record layer message */
MaxCipherRecLen = MaxRecLen + 2048,
RecHdrLen = 5,
MaxMacLen = SHA1dlen,
/* protocol versions we can accept */
TLSVersion = 0x0301,
SSL3Version = 0x0300,
ProtocolVersion = 0x0301, /* maximum version we speak */
MinProtoVersion = 0x0300, /* limits on version we accept */
MaxProtoVersion = 0x03ff,
/* connection states */
SHandshake = 1 << 0, /* doing handshake */
SOpen = 1 << 1, /* application data can be sent */
SRClose = 1 << 2, /* remote side has closed down */
SLClose = 1 << 3, /* sent a close notify alert */
SAlert = 1 << 5, /* sending or sent a fatal alert */
SError = 1 << 6, /* some sort of error has occured */
SClosed = 1 << 7, /* it is all over */
/* record types */
RChangeCipherSpec = 20,
RAlert,
RHandshake,
RApplication,
SSL2ClientHello = 1,
HSSL2ClientHello = 9, /* local convention; see tlshand.c */
/* alerts */
ECloseNotify = 0,
EUnexpectedMessage = 10,
EBadRecordMac = 20,
EDecryptionFailed = 21,
ERecordOverflow = 22,
EDecompressionFailure = 30,
EHandshakeFailure = 40,
ENoCertificate = 41,
EBadCertificate = 42,
EUnsupportedCertificate = 43,
ECertificateRevoked = 44,
ECertificateExpired = 45,
ECertificateUnknown = 46,
EIllegalParameter = 47,
EUnknownCa = 48,
EAccessDenied = 49,
EDecodeError = 50,
EDecryptError = 51,
EExportRestriction = 60,
EProtocolVersion = 70,
EInsufficientSecurity = 71,
EInternalError = 80,
EUserCanceled = 90,
ENoRenegotiation = 100,
EMAX = 256
};
struct Secret
{
char *encalg; /* name of encryption alg */
char *hashalg; /* name of hash alg */
int (*enc)(Secret*, uchar*, int);
int (*dec)(Secret*, uchar*, int);
int (*unpad)(uchar*, int, int);
DigestState *(*mac)(uchar*, ulong, uchar*, ulong, uchar*, DigestState*);
int block; /* encryption block len, 0 if none */
int maclen;
void *enckey;
uchar mackey[MaxMacLen];
};
struct OneWay
{
QLock io; /* locks io access */
QLock seclock; /* locks secret paramaters */
ulong seq;
Secret *sec; /* cipher in use */
Secret *new; /* cipher waiting for enable */
};
struct TlsRec
{
Chan *c; /* io channel */
int ref; /* serialized by tdlock for atomic destroy */
int version; /* version of the protocol we are speaking */
char verset; /* version has been set */
char opened; /* opened command every issued? */
char err[ERRMAX]; /* error message to return to handshake requests */
vlong handin; /* bytes communicated by the record layer */
vlong handout;
vlong datain;
vlong dataout;
Lock statelk;
int state;
/* record layer mac functions for different protocol versions */
void (*packMac)(Secret*, uchar*, uchar*, uchar*, uchar*, int, uchar*);
/* input side -- protected by in.io */
OneWay in;
Block *processed; /* next bunch of application data */
Block *unprocessed; /* data read from c but not parsed into records */
/* handshake queue */
Lock hqlock; /* protects hqref, alloc & free of handq, hprocessed */
int hqref;
Queue *handq; /* queue of handshake messages */
Block *hprocessed; /* remainder of last block read from handq */
QLock hqread; /* protects reads for hprocessed, handq */
/* output side */
OneWay out;
/* protections */
char *user;
int perm;
};
struct TlsErrs{
int err;
int sslerr;
int tlserr;
int fatal;
char *msg;
};
static TlsErrs tlserrs[] = {
{ECloseNotify, ECloseNotify, ECloseNotify, 0, "close notify"},
{EUnexpectedMessage, EUnexpectedMessage, EUnexpectedMessage, 1, "unexpected message"},
{EBadRecordMac, EBadRecordMac, EBadRecordMac, 1, "bad record mac"},
{EDecryptionFailed, EIllegalParameter, EDecryptionFailed, 1, "decryption failed"},
{ERecordOverflow, EIllegalParameter, ERecordOverflow, 1, "record too long"},
{EDecompressionFailure, EDecompressionFailure, EDecompressionFailure, 1, "decompression failed"},
{EHandshakeFailure, EHandshakeFailure, EHandshakeFailure, 1, "could not negotiate acceptable security paramters"},
{ENoCertificate, ENoCertificate, ECertificateUnknown, 1, "no appropriate certificate available"},
{EBadCertificate, EBadCertificate, EBadCertificate, 1, "corrupted or invalid certificate"},
{EUnsupportedCertificate, EUnsupportedCertificate, EUnsupportedCertificate, 1, "unsupported certificate type"},
{ECertificateRevoked, ECertificateRevoked, ECertificateRevoked, 1, "revoked certificate"},
{ECertificateExpired, ECertificateExpired, ECertificateExpired, 1, "expired certificate"},
{ECertificateUnknown, ECertificateUnknown, ECertificateUnknown, 1, "unacceptable certificate"},
{EIllegalParameter, EIllegalParameter, EIllegalParameter, 1, "illegal parameter"},
{EUnknownCa, EHandshakeFailure, EUnknownCa, 1, "unknown certificate authority"},
{EAccessDenied, EHandshakeFailure, EAccessDenied, 1, "access denied"},
{EDecodeError, EIllegalParameter, EDecodeError, 1, "error decoding message"},
{EDecryptError, EIllegalParameter, EDecryptError, 1, "error decrypting message"},
{EExportRestriction, EHandshakeFailure, EExportRestriction, 1, "export restriction violated"},
{EProtocolVersion, EIllegalParameter, EProtocolVersion, 1, "protocol version not supported"},
{EInsufficientSecurity, EHandshakeFailure, EInsufficientSecurity, 1, "stronger security routines required"},
{EInternalError, EHandshakeFailure, EInternalError, 1, "internal error"},
{EUserCanceled, ECloseNotify, EUserCanceled, 0, "handshake canceled by user"},
{ENoRenegotiation, EUnexpectedMessage, ENoRenegotiation, 0, "no renegotiation"},
};
enum
{
/* max. open tls connections */
MaxTlsDevs = 1024
};
static Lock tdlock;
static int tdhiwat;
static int maxtlsdevs = 128;
static TlsRec **tlsdevs;
static char **trnames;
static char *encalgs;
static char *hashalgs;
enum{
Qtopdir = 1, /* top level directory */
Qprotodir,
Qclonus,
Qencalgs,
Qhashalgs,
Qconvdir, /* directory for a conversation */
Qdata,
Qctl,
Qhand,
Qstatus,
Qstats,
};
#define TYPE(x) ((x).path & 0xf)
#define CONV(x) (((x).path >> 5)&(MaxTlsDevs-1))
#define QID(c, y) (((c)<<5) | (y))
static void checkstate(TlsRec *, int, int);
static void ensure(TlsRec*, Block**, int);
static void consume(Block**, uchar*, int);
static Chan* buftochan(char*);
static void tlshangup(TlsRec*);
static void tlsError(TlsRec*, char *);
static void alertHand(TlsRec*, char *);
static TlsRec *newtls(Chan *c);
static TlsRec *mktlsrec(void);
static DigestState*sslmac_md5(uchar *p, ulong len, uchar *key, ulong klen, uchar *digest, DigestState *s);
static DigestState*sslmac_sha1(uchar *p, ulong len, uchar *key, ulong klen, uchar *digest, DigestState *s);
static DigestState*nomac(uchar *p, ulong len, uchar *key, ulong klen, uchar *digest, DigestState *s);
static void sslPackMac(Secret *sec, uchar *mackey, uchar *seq, uchar *header, uchar *body, int len, uchar *mac);
static void tlsPackMac(Secret *sec, uchar *mackey, uchar *seq, uchar *header, uchar *body, int len, uchar *mac);
static void put64(uchar *p, vlong x);
static void put32(uchar *p, u32int);
static void put24(uchar *p, int);
static void put16(uchar *p, int);
static u32int get32(uchar *p);
static int get16(uchar *p);
static void tlsSetState(TlsRec *tr, int new, int old);
static void rcvAlert(TlsRec *tr, int err);
static void sendAlert(TlsRec *tr, int err);
static void rcvError(TlsRec *tr, int err, char *msg, ...);
static int rc4enc(Secret *sec, uchar *buf, int n);
static int des3enc(Secret *sec, uchar *buf, int n);
static int des3dec(Secret *sec, uchar *buf, int n);
static int noenc(Secret *sec, uchar *buf, int n);
static int sslunpad(uchar *buf, int n, int block);
static int tlsunpad(uchar *buf, int n, int block);
static void freeSec(Secret *sec);
static char *tlsstate(int s);
#pragma varargck argpos rcvError 3
static char *tlsnames[] = {
[Qclonus] "clone",
[Qencalgs] "encalgs",
[Qhashalgs] "hashalgs",
[Qdata] "data",
[Qctl] "ctl",
[Qhand] "hand",
[Qstatus] "status",
[Qstats] "stats",
};
static int convdir[] = { Qctl, Qdata, Qhand, Qstatus, Qstats };
static int
tlsgen(Chan *c, char*, Dirtab *, int, int s, Dir *dp)
{
Qid q;
TlsRec *tr;
char *name, *nm;
int perm, t;
q.vers = 0;
q.type = QTFILE;
t = TYPE(c->qid);
switch(t) {
case Qtopdir:
if(s == DEVDOTDOT){
q.path = QID(0, Qtopdir);
q.type = QTDIR;
devdir(c, q, "#a", 0, eve, 0555, dp);
return 1;
}
if(s > 0)
return -1;
q.path = QID(0, Qprotodir);
q.type = QTDIR;
devdir(c, q, "tls", 0, eve, 0555, dp);
return 1;
case Qprotodir:
if(s == DEVDOTDOT){
q.path = QID(0, Qtopdir);
q.type = QTDIR;
devdir(c, q, ".", 0, eve, 0555, dp);
return 1;
}
if(s < 3){
switch(s) {
default:
return -1;
case 0:
q.path = QID(0, Qclonus);
break;
case 1:
q.path = QID(0, Qencalgs);
break;
case 2:
q.path = QID(0, Qhashalgs);
break;
}
perm = 0444;
if(TYPE(q) == Qclonus)
perm = 0555;
devdir(c, q, tlsnames[TYPE(q)], 0, eve, perm, dp);
return 1;
}
s -= 3;
if(s >= tdhiwat)
return -1;
q.path = QID(s, Qconvdir);
q.type = QTDIR;
lock(&tdlock);
tr = tlsdevs[s];
if(tr != nil)
nm = tr->user;
else
nm = eve;
if((name = trnames[s]) == nil) {
name = trnames[s] = smalloc(16);
sprint(name, "%d", s);
}
devdir(c, q, name, 0, nm, 0555, dp);
unlock(&tdlock);
return 1;
case Qconvdir:
if(s == DEVDOTDOT){
q.path = QID(0, Qprotodir);
q.type = QTDIR;
devdir(c, q, "tls", 0, eve, 0555, dp);
return 1;
}
if(s < 0 || s >= nelem(convdir))
return -1;
lock(&tdlock);
tr = tlsdevs[CONV(c->qid)];
if(tr != nil){
nm = tr->user;
perm = tr->perm;
}else{
perm = 0;
nm = eve;
}
t = convdir[s];
if(t == Qstatus || t == Qstats)
perm &= 0444;
q.path = QID(CONV(c->qid), t);
devdir(c, q, tlsnames[t], 0, nm, perm, dp);
unlock(&tdlock);
return 1;
case Qclonus:
case Qencalgs:
case Qhashalgs:
perm = 0444;
if(t == Qclonus)
perm = 0555;
devdir(c, c->qid, tlsnames[t], 0, eve, perm, dp);
return 1;
default:
lock(&tdlock);
tr = tlsdevs[CONV(c->qid)];
if(tr != nil){
nm = tr->user;
perm = tr->perm;
}else{
perm = 0;
nm = eve;
}
if(t == Qstatus || t == Qstats)
perm &= 0444;
devdir(c, c->qid, tlsnames[t], 0, nm, perm, dp);
unlock(&tdlock);
return 1;
}
return -1;
}
static Chan*
tlsattach(char *spec)
{
Chan *c;
c = devattach('a', spec);
c->qid.path = QID(0, Qtopdir);
c->qid.type = QTDIR;
c->qid.vers = 0;
return c;
}
static Walkqid*
tlswalk(Chan *c, Chan *nc, char **name, int nname)
{
return devwalk(c, nc, name, nname, nil, 0, tlsgen);
}
static int
tlsstat(Chan *c, uchar *db, int n)
{
return devstat(c, db, n, nil, 0, tlsgen);
}
static Chan*
tlsopen(Chan *c, int omode)
{
TlsRec *tr, **pp;
int t, perm;
perm = 0;
omode &= 3;
switch(omode) {
case OREAD:
perm = 4;
break;
case OWRITE:
perm = 2;
break;
case ORDWR:
perm = 6;
break;
}
t = TYPE(c->qid);
switch(t) {
default:
panic("tlsopen");
case Qtopdir:
case Qprotodir:
case Qconvdir:
if(omode != OREAD)
error(Eperm);
break;
case Qclonus:
tr = newtls(c);
if(tr == nil)
error(Enodev);
break;
case Qctl:
case Qdata:
case Qhand:
case Qstatus:
case Qstats:
if((t == Qstatus || t == Qstats) && omode != OREAD)
error(Eperm);
if(waserror()) {
unlock(&tdlock);
nexterror();
}
lock(&tdlock);
pp = &tlsdevs[CONV(c->qid)];
tr = *pp;
if(tr == nil)
error("must open connection using clone");
if((perm & (tr->perm>>6)) != perm
&& (strcmp(up->user, tr->user) != 0
|| (perm & tr->perm) != perm))
error(Eperm);
if(t == Qhand){
if(waserror()){
unlock(&tr->hqlock);
nexterror();
}
lock(&tr->hqlock);
if(tr->handq != nil)
error(Einuse);
tr->handq = qopen(2 * MaxCipherRecLen, 0, nil, nil);
if(tr->handq == nil)
error("can't allocate handshake queue");
tr->hqref = 1;
unlock(&tr->hqlock);
poperror();
}
tr->ref++;
unlock(&tdlock);
poperror();
break;
case Qencalgs:
case Qhashalgs:
if(omode != OREAD)
error(Eperm);
break;
}
c->mode = openmode(omode);
c->flag |= COPEN;
c->offset = 0;
c->iounit = qiomaxatomic;
return c;
}
static int
tlswstat(Chan *c, uchar *dp, int n)
{
Dir *d;
TlsRec *tr;
int rv;
d = nil;
if(waserror()){
free(d);
unlock(&tdlock);
nexterror();
}
lock(&tdlock);
tr = tlsdevs[CONV(c->qid)];
if(tr == nil)
error(Ebadusefd);
if(strcmp(tr->user, up->user) != 0)
error(Eperm);
d = smalloc(n + sizeof *d);
rv = convM2D(dp, n, &d[0], (char*) &d[1]);
if(rv == 0)
error(Eshortstat);
if(!emptystr(d->uid))
kstrdup(&tr->user, d->uid);
if(d->mode != ~0UL)
tr->perm = d->mode;
free(d);
poperror();
unlock(&tdlock);
return rv;
}
static void
dechandq(TlsRec *tr)
{
lock(&tr->hqlock);
if(--tr->hqref == 0){
if(tr->handq != nil){
qfree(tr->handq);
tr->handq = nil;
}
if(tr->hprocessed != nil){
freeb(tr->hprocessed);
tr->hprocessed = nil;
}
}
unlock(&tr->hqlock);
}
static void
tlsclose(Chan *c)
{
TlsRec *tr;
int t;
t = TYPE(c->qid);
switch(t) {
case Qctl:
case Qdata:
case Qhand:
case Qstatus:
case Qstats:
if((c->flag & COPEN) == 0)
break;
tr = tlsdevs[CONV(c->qid)];
if(tr == nil)
break;
if(t == Qhand)
dechandq(tr);
lock(&tdlock);
if(--tr->ref > 0) {
unlock(&tdlock);
return;
}
tlsdevs[CONV(c->qid)] = nil;
unlock(&tdlock);
if(tr->c != nil && !waserror()){
checkstate(tr, 0, SOpen|SHandshake|SRClose);
sendAlert(tr, ECloseNotify);
poperror();
}
tlshangup(tr);
if(tr->c != nil)
cclose(tr->c);
freeSec(tr->in.sec);
freeSec(tr->in.new);
freeSec(tr->out.sec);
freeSec(tr->out.new);
free(tr->user);
free(tr);
break;
}
}
/*
* make sure we have at least 'n' bytes in list 'l'
*/
static void
ensure(TlsRec *s, Block **l, int n)
{
int sofar, i;
Block *b, *bl;
sofar = 0;
for(b = *l; b; b = b->next){
sofar += BLEN(b);
if(sofar >= n)
return;
l = &b->next;
}
while(sofar < n){
bl = devtab[s->c->type]->bread(s->c, MaxCipherRecLen + RecHdrLen, 0);
if(bl == 0)
error(Ehungup);
*l = bl;
i = 0;
for(b = bl; b; b = b->next){
i += BLEN(b);
l = &b->next;
}
if(i == 0)
error(Ehungup);
sofar += i;
}
}
/*
* copy 'n' bytes from 'l' into 'p' and free
* the bytes in 'l'
*/
static void
consume(Block **l, uchar *p, int n)
{
Block *b;
int i;
for(; *l && n > 0; n -= i){
b = *l;
i = BLEN(b);
if(i > n)
i = n;
memmove(p, b->rp, i);
b->rp += i;
p += i;
if(BLEN(b) < 0)
panic("consume");
if(BLEN(b))
break;
*l = b->next;
freeb(b);
}
}
/*
* give back n bytes
*/
static void
regurgitate(TlsRec *s, uchar *p, int n)
{
Block *b;
if(n <= 0)
return;
b = s->unprocessed;
if(s->unprocessed == nil || b->rp - b->base < n) {
b = allocb(n);
memmove(b->wp, p, n);
b->wp += n;
b->next = s->unprocessed;
s->unprocessed = b;
} else {
b->rp -= n;
memmove(b->rp, p, n);
}
}
/*
* remove at most n bytes from the queue
*/
static Block*
qgrab(Block **l, int n)
{
Block *bb, *b;
int i;
b = *l;
if(BLEN(b) == n){
*l = b->next;
b->next = nil;
return b;
}
i = 0;
for(bb = b; bb != nil && i < n; bb = bb->next)
i += BLEN(bb);
if(i > n)
i = n;
bb = allocb(i);
consume(l, bb->wp, i);
bb->wp += i;
return bb;
}
static void
tlsclosed(TlsRec *tr, int new)
{
lock(&tr->statelk);
if(tr->state == SOpen || tr->state == SHandshake)
tr->state = new;
else if((new | tr->state) == (SRClose|SLClose))
tr->state = SClosed;
unlock(&tr->statelk);
alertHand(tr, "close notify");
}
/*
* read and process one tls record layer message
* must be called with tr->in.io held
* We can't let Eintrs lose data, since doing so will get
* us out of sync with the sender and break the reliablity
* of the channel. Eintr only happens during the reads in
* consume. Therefore we put back any bytes consumed before
* the last call to ensure.
*/
static void
tlsrecread(TlsRec *tr)
{
OneWay *volatile in;
Block *volatile b;
uchar *p, seq[8], header[RecHdrLen], hmac[MD5dlen];
int volatile nconsumed;
int len, type, ver, unpad_len;
nconsumed = 0;
if(waserror()){
if(strcmp(up->errstr, Eintr) == 0 && !waserror()){
regurgitate(tr, header, nconsumed);
poperror();
}else
tlsError(tr, "channel error");
nexterror();
}
ensure(tr, &tr->unprocessed, RecHdrLen);
consume(&tr->unprocessed, header, RecHdrLen);
nconsumed = RecHdrLen;
if((tr->handin == 0) && (header[0] & 0x80)){
/* Cope with an SSL3 ClientHello expressed in SSL2 record format.
This is sent by some clients that we must interoperate
with, such as Java's JSSE and Microsoft's Internet Explorer. */
len = (get16(header) & ~0x8000) - 3;
type = header[2];
ver = get16(header + 3);
if(type != SSL2ClientHello || len < 22)
rcvError(tr, EProtocolVersion, "invalid initial SSL2-like message");
}else{ /* normal SSL3 record format */
type = header[0];
ver = get16(header+1);
len = get16(header+3);
}
if(ver != tr->version && (tr->verset || ver < MinProtoVersion || ver > MaxProtoVersion))
rcvError(tr, EProtocolVersion, "devtls expected ver=%x%s, saw (len=%d) type=%x ver=%x '%.12s'",
tr->version, tr->verset?"/set":"", len, type, ver, (char*)header);
if(len > MaxCipherRecLen || len < 0)
rcvError(tr, ERecordOverflow, "record message too long %d", len);
ensure(tr, &tr->unprocessed, len);
nconsumed = 0;
poperror();
/*
* If an Eintr happens after this, we'll get out of sync.
* Make sure nothing we call can sleep.
* Errors are ok, as they kill the connection.
* Luckily, allocb won't sleep, it'll just error out.
*/
b = nil;
if(waserror()){
if(b != nil)
freeb(b);
tlsError(tr, "channel error");
nexterror();
}
b = qgrab(&tr->unprocessed, len);
in = &tr->in;
if(waserror()){
qunlock(&in->seclock);
nexterror();
}
qlock(&in->seclock);
p = b->rp;
if(in->sec != nil) {
/* to avoid Canvel-Hiltgen-Vaudenay-Vuagnoux attack, all errors here
should look alike, including timing of the response. */
unpad_len = (*in->sec->dec)(in->sec, p, len);
if(unpad_len > in->sec->maclen)
len = unpad_len - in->sec->maclen;
/* update length */
put16(header+3, len);
put64(seq, in->seq);
in->seq++;
(*tr->packMac)(in->sec, in->sec->mackey, seq, header, p, len, hmac);
if(unpad_len <= in->sec->maclen || memcmp(hmac, p+len, in->sec->maclen) != 0)
rcvError(tr, EBadRecordMac, "record mac mismatch");
b->wp = b->rp + len;
}
qunlock(&in->seclock);
poperror();
if(len <= 0)
rcvError(tr, EDecodeError, "runt record message");
switch(type) {
default:
rcvError(tr, EIllegalParameter, "invalid record message 0x%x", type);
break;
case RChangeCipherSpec:
if(len != 1 || p[0] != 1)
rcvError(tr, EDecodeError, "invalid change cipher spec");
qlock(&in->seclock);
if(in->new == nil){
qunlock(&in->seclock);
rcvError(tr, EUnexpectedMessage, "unexpected change cipher spec");
}
freeSec(in->sec);
in->sec = in->new;
in->new = nil;
in->seq = 0;
qunlock(&in->seclock);
break;
case RAlert:
if(len != 2)
rcvError(tr, EDecodeError, "invalid alert");
if(p[0] == 2)
rcvAlert(tr, p[1]);
if(p[0] != 1)
rcvError(tr, EIllegalParameter, "invalid alert fatal code");
/*
* propate non-fatal alerts to handshaker
*/
if(p[1] == ECloseNotify) {
tlsclosed(tr, SRClose);
if(tr->opened)
error("tls hungup");
error("close notify");
}
if(p[1] == ENoRenegotiation)
alertHand(tr, "no renegotiation");
else if(p[1] == EUserCanceled)
alertHand(tr, "handshake canceled by user");
else
rcvError(tr, EIllegalParameter, "invalid alert code");
break;
case RHandshake:
/*
* don't worry about dropping the block
* qbwrite always queues even if flow controlled and interrupted.
*
* if there isn't any handshaker, ignore the request,
* but notify the other side we are doing so.
*/
lock(&tr->hqlock);
if(tr->handq != nil){
tr->hqref++;
unlock(&tr->hqlock);
if(waserror()){
dechandq(tr);
nexterror();
}
b = padblock(b, 1);
*b->rp = RHandshake;
qbwrite(tr->handq, b);
b = nil;
poperror();
dechandq(tr);
}else{
unlock(&tr->hqlock);
if(tr->verset && tr->version != SSL3Version && !waserror()){
sendAlert(tr, ENoRenegotiation);
poperror();
}
}
break;
case SSL2ClientHello:
lock(&tr->hqlock);
if(tr->handq != nil){
tr->hqref++;
unlock(&tr->hqlock);
if(waserror()){
dechandq(tr);
nexterror();
}
/* Pass the SSL2 format data, so that the handshake code can compute
the correct checksums. HSSL2ClientHello = HandshakeType 9 is
unused in RFC2246. */
b = padblock(b, 8);
b->rp[0] = RHandshake;
b->rp[1] = HSSL2ClientHello;
put24(&b->rp[2], len+3);
b->rp[5] = SSL2ClientHello;
put16(&b->rp[6], ver);
qbwrite(tr->handq, b);
b = nil;
poperror();
dechandq(tr);
}else{
unlock(&tr->hqlock);
if(tr->verset && tr->version != SSL3Version && !waserror()){
sendAlert(tr, ENoRenegotiation);
poperror();
}
}
break;
case RApplication:
if(!tr->opened)
rcvError(tr, EUnexpectedMessage, "application message received before handshake completed");
tr->processed = b;
b = nil;
break;
}
if(b != nil)
freeb(b);
poperror();
}
/*
* got a fatal alert message
*/
static void
rcvAlert(TlsRec *tr, int err)
{
char *s;
int i;
s = "unknown error";
for(i=0; i < nelem(tlserrs); i++){
if(tlserrs[i].err == err){
s = tlserrs[i].msg;
break;
}
}
tlsError(tr, s);
if(!tr->opened)
error(s);
error("tls error");
}
/*
* found an error while decoding the input stream
*/
static void
rcvError(TlsRec *tr, int err, char *fmt, ...)
{
char msg[ERRMAX];
va_list arg;
va_start(arg, fmt);
vseprint(msg, msg+sizeof(msg), fmt, arg);
va_end(arg);
sendAlert(tr, err);
if(!tr->opened)
error(msg);
error("tls error");
}
/*
* make sure the next hand operation returns with a 'msg' error
*/
static void
alertHand(TlsRec *tr, char *msg)
{
Block *b;
int n;
lock(&tr->hqlock);
if(tr->handq == nil){
unlock(&tr->hqlock);
return;
}
tr->hqref++;
unlock(&tr->hqlock);
n = strlen(msg);
if(waserror()){
dechandq(tr);
nexterror();
}
b = allocb(n + 2);
*b->wp++ = RAlert;
memmove(b->wp, msg, n + 1);
b->wp += n + 1;
qbwrite(tr->handq, b);
poperror();
dechandq(tr);
}
static void
checkstate(TlsRec *tr, int ishand, int ok)
{
int state;
lock(&tr->statelk);
state = tr->state;
unlock(&tr->statelk);
if(state & ok)
return;
switch(state){
case SHandshake:
case SOpen:
break;
case SError:
case SAlert:
if(ishand)
error(tr->err);
error("tls error");
case SRClose:
case SLClose:
case SClosed:
error("tls hungup");
}
error("tls improperly configured");
}
static Block*
tlsbread(Chan *c, long n, ulong offset)
{
int ty;
Block *b;
TlsRec *volatile tr;
ty = TYPE(c->qid);
switch(ty) {
default:
return devbread(c, n, offset);
case Qhand:
case Qdata:
break;
}
tr = tlsdevs[CONV(c->qid)];
if(tr == nil)
panic("tlsbread");
if(waserror()){
qunlock(&tr->in.io);
nexterror();
}
qlock(&tr->in.io);
if(ty == Qdata){
checkstate(tr, 0, SOpen);
while(tr->processed == nil)
tlsrecread(tr);
/* return at most what was asked for */
b = qgrab(&tr->processed, n);
qunlock(&tr->in.io);
poperror();
tr->datain += BLEN(b);
}else{
checkstate(tr, 1, SOpen|SHandshake|SLClose);
/*
* it's ok to look at state without the lock
* since it only protects reading records,
* and we have that tr->in.io held.
*/
while(!tr->opened && tr->hprocessed == nil && !qcanread(tr->handq))
tlsrecread(tr);
qunlock(&tr->in.io);
poperror();
if(waserror()){
qunlock(&tr->hqread);
nexterror();
}
qlock(&tr->hqread);
if(tr->hprocessed == nil){
b = qbread(tr->handq, MaxRecLen + 1);
if(*b->rp++ == RAlert){
strecpy(up->errstr, up->errstr+ERRMAX, (char*)b->rp);
freeb(b);
nexterror();
}
tr->hprocessed = b;
}
b = qgrab(&tr->hprocessed, n);
poperror();
qunlock(&tr->hqread);
tr->handin += BLEN(b);
}
return b;
}
static long
tlsread(Chan *c, void *a, long n, vlong off)
{
Block *volatile b;
Block *nb;
uchar *va;
int i, ty;
char *buf, *s, *e;
ulong offset = off;
TlsRec * tr;
if(c->qid.type & QTDIR)
return devdirread(c, a, n, 0, 0, tlsgen);
tr = tlsdevs[CONV(c->qid)];
ty = TYPE(c->qid);
switch(ty) {
default:
error(Ebadusefd);
case Qstatus:
buf = smalloc(Statlen);
qlock(&tr->in.seclock);
qlock(&tr->out.seclock);
s = buf;
e = buf + Statlen;
s = seprint(s, e, "State: %s\n", tlsstate(tr->state));
s = seprint(s, e, "Version: 0x%x\n", tr->version);
if(tr->in.sec != nil)
s = seprint(s, e, "EncIn: %s\nHashIn: %s\n", tr->in.sec->encalg, tr->in.sec->hashalg);
if(tr->in.new != nil)
s = seprint(s, e, "NewEncIn: %s\nNewHashIn: %s\n", tr->in.new->encalg, tr->in.new->hashalg);
if(tr->out.sec != nil)
s = seprint(s, e, "EncOut: %s\nHashOut: %s\n", tr->out.sec->encalg, tr->out.sec->hashalg);
if(tr->out.new != nil)
seprint(s, e, "NewEncOut: %s\nNewHashOut: %s\n", tr->out.new->encalg, tr->out.new->hashalg);
qunlock(&tr->in.seclock);
qunlock(&tr->out.seclock);
n = readstr(offset, a, n, buf);
free(buf);
return n;
case Qstats:
buf = smalloc(Statlen);
s = buf;
e = buf + Statlen;
s = seprint(s, e, "DataIn: %lld\n", tr->datain);
s = seprint(s, e, "DataOut: %lld\n", tr->dataout);
s = seprint(s, e, "HandIn: %lld\n", tr->handin);
seprint(s, e, "HandOut: %lld\n", tr->handout);
n = readstr(offset, a, n, buf);
free(buf);
return n;
case Qctl:
buf = smalloc(Statlen);
snprint(buf, Statlen, "%llud", CONV(c->qid));
n = readstr(offset, a, n, buf);
free(buf);
return n;
case Qdata:
case Qhand:
b = tlsbread(c, n, offset);
break;
case Qencalgs:
return readstr(offset, a, n, encalgs);
case Qhashalgs:
return readstr(offset, a, n, hashalgs);
}
if(waserror()){
freeblist(b);
nexterror();
}
n = 0;
va = a;
for(nb = b; nb; nb = nb->next){
i = BLEN(nb);
memmove(va+n, nb->rp, i);
n += i;
}
freeblist(b);
poperror();
return n;
}
/*
* write a block in tls records
*/
static void
tlsrecwrite(TlsRec *tr, int type, Block *b)
{
Block *volatile bb;
Block *nb;
uchar *p, seq[8];
OneWay *volatile out;
int n, maclen, pad, ok;
out = &tr->out;
bb = b;
if(waserror()){
qunlock(&out->io);
if(bb != nil)
freeb(bb);
nexterror();
}
qlock(&out->io);
ok = SHandshake|SOpen|SRClose;
if(type == RAlert)
ok |= SAlert;
while(bb != nil){
checkstate(tr, type != RApplication, ok);
/*
* get at most one maximal record's input,
* with padding on the front for header and
* back for mac and maximal block padding.
*/
if(waserror()){
qunlock(&out->seclock);
nexterror();
}
qlock(&out->seclock);
maclen = 0;
pad = 0;
if(out->sec != nil){
maclen = out->sec->maclen;
pad = maclen + out->sec->block;
}
n = BLEN(bb);
if(n > MaxRecLen){
n = MaxRecLen;
nb = allocb(n + pad + RecHdrLen);
memmove(nb->wp + RecHdrLen, bb->rp, n);
bb->rp += n;
}else{
/*
* carefully reuse bb so it will get freed if we're out of memory
*/
bb = padblock(bb, RecHdrLen);
if(pad)
nb = padblock(bb, -pad);
else
nb = bb;
bb = nil;
}
p = nb->rp;
p[0] = type;
put16(p+1, tr->version);
put16(p+3, n);
if(out->sec != nil){
put64(seq, out->seq);
out->seq++;
(*tr->packMac)(out->sec, out->sec->mackey, seq, p, p + RecHdrLen, n, p + RecHdrLen + n);
n += maclen;
/* encrypt */
n = (*out->sec->enc)(out->sec, p + RecHdrLen, n);
nb->wp = p + RecHdrLen + n;
/* update length */
put16(p+3, n);
}
if(type == RChangeCipherSpec){
if(out->new == nil)
error("change cipher without a new cipher");
freeSec(out->sec);
out->sec = out->new;
out->new = nil;
out->seq = 0;
}
qunlock(&out->seclock);
poperror();
/*
* if bwrite error's, we assume the block is queued.
* if not, we're out of sync with the receiver and will not recover.
*/
if(waserror()){
if(strcmp(up->errstr, "interrupted") != 0)
tlsError(tr, "channel error");
nexterror();
}
devtab[tr->c->type]->bwrite(tr->c, nb, 0);
poperror();
}
qunlock(&out->io);
poperror();
}
static long
tlsbwrite(Chan *c, Block *b, ulong offset)
{
int ty;
ulong n;
TlsRec *tr;
n = BLEN(b);
tr = tlsdevs[CONV(c->qid)];
if(tr == nil)
panic("tlsbread");
ty = TYPE(c->qid);
switch(ty) {
default:
return devbwrite(c, b, offset);
case Qhand:
tlsrecwrite(tr, RHandshake, b);
tr->handout += n;
break;
case Qdata:
checkstate(tr, 0, SOpen);
tlsrecwrite(tr, RApplication, b);
tr->dataout += n;
break;
}
return n;
}
typedef struct Hashalg Hashalg;
struct Hashalg
{
char *name;
int maclen;
void (*initkey)(Hashalg *, int, Secret *, uchar*);
};
static void
initmd5key(Hashalg *ha, int version, Secret *s, uchar *p)
{
s->maclen = ha->maclen;
if(version == SSL3Version)
s->mac = sslmac_md5;
else
s->mac = hmac_md5;
memmove(s->mackey, p, ha->maclen);
}
static void
initclearmac(Hashalg *, int, Secret *s, uchar *)
{
s->maclen = 0;
s->mac = nomac;
}
static void
initsha1key(Hashalg *ha, int version, Secret *s, uchar *p)
{
s->maclen = ha->maclen;
if(version == SSL3Version)
s->mac = sslmac_sha1;
else
s->mac = hmac_sha1;
memmove(s->mackey, p, ha->maclen);
}
static Hashalg hashtab[] =
{
{ "clear", 0, initclearmac, },
{ "md5", MD5dlen, initmd5key, },
{ "sha1", SHA1dlen, initsha1key, },
{ 0 }
};
static Hashalg*
parsehashalg(char *p)
{
Hashalg *ha;
for(ha = hashtab; ha->name; ha++)
if(strcmp(p, ha->name) == 0)
return ha;
error("unsupported hash algorithm");
return nil;
}
typedef struct Encalg Encalg;
struct Encalg
{
char *name;
int keylen;
int ivlen;
void (*initkey)(Encalg *ea, Secret *, uchar*, uchar*);
};
static void
initRC4key(Encalg *ea, Secret *s, uchar *p, uchar *)
{
s->enckey = smalloc(sizeof(RC4state));
s->enc = rc4enc;
s->dec = rc4enc;
s->block = 0;
setupRC4state(s->enckey, p, ea->keylen);
}
static void
initDES3key(Encalg *, Secret *s, uchar *p, uchar *iv)
{
s->enckey = smalloc(sizeof(DES3state));
s->enc = des3enc;
s->dec = des3dec;
s->block = 8;
setupDES3state(s->enckey, (uchar(*)[8])p, iv);
}
static void
initclearenc(Encalg *, Secret *s, uchar *, uchar *)
{
s->enc = noenc;
s->dec = noenc;
s->block = 0;
}
static Encalg encrypttab[] =
{
{ "clear", 0, 0, initclearenc },
{ "rc4_128", 128/8, 0, initRC4key },
{ "3des_ede_cbc", 3 * 8, 8, initDES3key },
{ 0 }
};
static Encalg*
parseencalg(char *p)
{
Encalg *ea;
for(ea = encrypttab; ea->name; ea++)
if(strcmp(p, ea->name) == 0)
return ea;
error("unsupported encryption algorithm");
return nil;
}
static long
tlswrite(Chan *c, void *a, long n, vlong off)
{
Encalg *ea;
Hashalg *ha;
TlsRec *volatile tr;
Secret *volatile tos, *volatile toc;
Block *volatile b;
Cmdbuf *volatile cb;
int m, ty;
char *p, *e;
uchar *volatile x;
ulong offset = off;
tr = tlsdevs[CONV(c->qid)];
if(tr == nil)
panic("tlswrite");
ty = TYPE(c->qid);
switch(ty){
case Qdata:
case Qhand:
p = a;
e = p + n;
do{
m = e - p;
if(m > MaxRecLen)
m = MaxRecLen;
b = allocb(m);
if(waserror()){
freeb(b);
nexterror();
}
memmove(b->wp, p, m);
poperror();
b->wp += m;
tlsbwrite(c, b, offset);
p += m;
}while(p < e);
return n;
case Qctl:
break;
default:
error(Ebadusefd);
return -1;
}
cb = parsecmd(a, n);
if(waserror()){
free(cb);
nexterror();
}
if(cb->nf < 1)
error("short control request");
/* mutex with operations using what we're about to change */
if(waserror()){
qunlock(&tr->in.seclock);
qunlock(&tr->out.seclock);
nexterror();
}
qlock(&tr->in.seclock);
qlock(&tr->out.seclock);
if(strcmp(cb->f[0], "fd") == 0){
if(cb->nf != 3)
error("usage: fd open-fd version");
if(tr->c != nil)
error(Einuse);
m = strtol(cb->f[2], nil, 0);
if(m < MinProtoVersion || m > MaxProtoVersion)
error("unsupported version");
tr->c = buftochan(cb->f[1]);
tr->version = m;
tlsSetState(tr, SHandshake, SClosed);
}else if(strcmp(cb->f[0], "version") == 0){
if(cb->nf != 2)
error("usage: version vers");
if(tr->c == nil)
error("must set fd before version");
if(tr->verset)
error("version already set");
m = strtol(cb->f[1], nil, 0);
if(m == SSL3Version)
tr->packMac = sslPackMac;
else if(m == TLSVersion)
tr->packMac = tlsPackMac;
else
error("unsupported version");
tr->verset = 1;
tr->version = m;
}else if(strcmp(cb->f[0], "secret") == 0){
if(cb->nf != 5)
error("usage: secret hashalg encalg isclient secretdata");
if(tr->c == nil || !tr->verset)
error("must set fd and version before secrets");
if(tr->in.new != nil){
freeSec(tr->in.new);
tr->in.new = nil;
}
if(tr->out.new != nil){
freeSec(tr->out.new);
tr->out.new = nil;
}
ha = parsehashalg(cb->f[1]);
ea = parseencalg(cb->f[2]);
p = cb->f[4];
m = (strlen(p)*3)/2;
x = smalloc(m);
tos = nil;
toc = nil;
if(waserror()){
freeSec(tos);
freeSec(toc);
free(x);
nexterror();
}
m = dec64(x, m, p, strlen(p));
if(m < 2 * ha->maclen + 2 * ea->keylen + 2 * ea->ivlen)
error("not enough secret data provided");
tos = smalloc(sizeof(Secret));
toc = smalloc(sizeof(Secret));
if(!ha->initkey || !ea->initkey)
error("misimplemented secret algorithm");
(*ha->initkey)(ha, tr->version, tos, &x[0]);
(*ha->initkey)(ha, tr->version, toc, &x[ha->maclen]);
(*ea->initkey)(ea, tos, &x[2 * ha->maclen], &x[2 * ha->maclen + 2 * ea->keylen]);
(*ea->initkey)(ea, toc, &x[2 * ha->maclen + ea->keylen], &x[2 * ha->maclen + 2 * ea->keylen + ea->ivlen]);
if(!tos->mac || !tos->enc || !tos->dec
|| !toc->mac || !toc->enc || !toc->dec)
error("missing algorithm implementations");
if(strtol(cb->f[3], nil, 0) == 0){
tr->in.new = tos;
tr->out.new = toc;
}else{
tr->in.new = toc;
tr->out.new = tos;
}
if(tr->version == SSL3Version){
toc->unpad = sslunpad;
tos->unpad = sslunpad;
}else{
toc->unpad = tlsunpad;
tos->unpad = tlsunpad;
}
toc->encalg = ea->name;
toc->hashalg = ha->name;
tos->encalg = ea->name;
tos->hashalg = ha->name;
free(x);
poperror();
}else if(strcmp(cb->f[0], "changecipher") == 0){
if(cb->nf != 1)
error("usage: changecipher");
if(tr->out.new == nil)
error("can't change cipher spec without setting secret");
qunlock(&tr->in.seclock);
qunlock(&tr->out.seclock);
poperror();
free(cb);
poperror();
/*
* the real work is done as the message is written
* so the stream is encrypted in sync.
*/
b = allocb(1);
*b->wp++ = 1;
tlsrecwrite(tr, RChangeCipherSpec, b);
return n;
}else if(strcmp(cb->f[0], "opened") == 0){
if(cb->nf != 1)
error("usage: opened");
if(tr->in.sec == nil || tr->out.sec == nil)
error("cipher must be configured before enabling data messages");
lock(&tr->statelk);
if(tr->state != SHandshake && tr->state != SOpen){
unlock(&tr->statelk);
error("can't enable data messages");
}
tr->state = SOpen;
unlock(&tr->statelk);
tr->opened = 1;
}else if(strcmp(cb->f[0], "alert") == 0){
if(cb->nf != 2)
error("usage: alert n");
if(tr->c == nil)
error("must set fd before sending alerts");
m = strtol(cb->f[1], nil, 0);
qunlock(&tr->in.seclock);
qunlock(&tr->out.seclock);
poperror();
free(cb);
poperror();
sendAlert(tr, m);
if(m == ECloseNotify)
tlsclosed(tr, SLClose);
return n;
} else
error(Ebadarg);
qunlock(&tr->in.seclock);
qunlock(&tr->out.seclock);
poperror();
free(cb);
poperror();
return n;
}
static void
tlsinit(void)
{
struct Encalg *e;
struct Hashalg *h;
int n;
char *cp;
tlsdevs = smalloc(sizeof(TlsRec*) * maxtlsdevs);
trnames = smalloc((sizeof *trnames) * maxtlsdevs);
n = 1;
for(e = encrypttab; e->name != nil; e++)
n += strlen(e->name) + 1;
cp = encalgs = smalloc(n);
for(e = encrypttab;;){
strcpy(cp, e->name);
cp += strlen(e->name);
e++;
if(e->name == nil)
break;
*cp++ = ' ';
}
*cp = 0;
n = 1;
for(h = hashtab; h->name != nil; h++)
n += strlen(h->name) + 1;
cp = hashalgs = smalloc(n);
for(h = hashtab;;){
strcpy(cp, h->name);
cp += strlen(h->name);
h++;
if(h->name == nil)
break;
*cp++ = ' ';
}
*cp = 0;
}
Dev tlsdevtab = {
'a',
"tls",
devreset,
tlsinit,
devshutdown,
tlsattach,
tlswalk,
tlsstat,
tlsopen,
devcreate,
tlsclose,
tlsread,
tlsbread,
tlswrite,
tlsbwrite,
devremove,
tlswstat,
};
/* get channel associated with an fd */
static Chan*
buftochan(char *p)
{
Chan *c;
int fd;
if(p == 0)
error(Ebadarg);
fd = strtoul(p, 0, 0);
if(fd < 0)
error(Ebadarg);
c = fdtochan(fd, -1, 0, 1); /* error check and inc ref */
return c;
}
static void
sendAlert(TlsRec *tr, int err)
{
Block *b;
int i, fatal;
char *msg;
fatal = 1;
msg = "tls unknown alert";
for(i=0; i < nelem(tlserrs); i++) {
if(tlserrs[i].err == err) {
msg = tlserrs[i].msg;
if(tr->version == SSL3Version)
err = tlserrs[i].sslerr;
else
err = tlserrs[i].tlserr;
fatal = tlserrs[i].fatal;
break;
}
}
if(!waserror()){
b = allocb(2);
*b->wp++ = fatal + 1;
*b->wp++ = err;
if(fatal)
tlsSetState(tr, SAlert, SOpen|SHandshake|SRClose);
tlsrecwrite(tr, RAlert, b);
poperror();
}
if(fatal)
tlsError(tr, msg);
}
static void
tlsError(TlsRec *tr, char *msg)
{
int s;
lock(&tr->statelk);
s = tr->state;
tr->state = SError;
if(s != SError){
strncpy(tr->err, msg, ERRMAX - 1);
tr->err[ERRMAX - 1] = '\0';
}
unlock(&tr->statelk);
if(s != SError)
alertHand(tr, msg);
}
static void
tlsSetState(TlsRec *tr, int new, int old)
{
lock(&tr->statelk);
if(tr->state & old)
tr->state = new;
unlock(&tr->statelk);
}
/* hand up a digest connection */
static void
tlshangup(TlsRec *tr)
{
Block *b;
qlock(&tr->in.io);
for(b = tr->processed; b; b = tr->processed){
tr->processed = b->next;
freeb(b);
}
if(tr->unprocessed != nil){
freeb(tr->unprocessed);
tr->unprocessed = nil;
}
qunlock(&tr->in.io);
tlsSetState(tr, SClosed, ~0);
}
static TlsRec*
newtls(Chan *ch)
{
TlsRec **pp, **ep, **np;
char **nmp;
int t, newmax;
if(waserror()) {
unlock(&tdlock);
nexterror();
}
lock(&tdlock);
ep = &tlsdevs[maxtlsdevs];
for(pp = tlsdevs; pp < ep; pp++)
if(*pp == nil)
break;
if(pp >= ep) {
if(maxtlsdevs >= MaxTlsDevs) {
unlock(&tdlock);
poperror();
return nil;
}
newmax = 2 * maxtlsdevs;
if(newmax > MaxTlsDevs)
newmax = MaxTlsDevs;
np = smalloc(sizeof(TlsRec*) * newmax);
memmove(np, tlsdevs, sizeof(TlsRec*) * maxtlsdevs);
tlsdevs = np;
pp = &tlsdevs[maxtlsdevs];
memset(pp, 0, sizeof(TlsRec*)*(newmax - maxtlsdevs));
nmp = smalloc(sizeof *nmp * newmax);
memmove(nmp, trnames, sizeof *nmp * maxtlsdevs);
trnames = nmp;
maxtlsdevs = newmax;
}
*pp = mktlsrec();
if(pp - tlsdevs >= tdhiwat)
tdhiwat++;
t = TYPE(ch->qid);
if(t == Qclonus)
t = Qctl;
ch->qid.path = QID(pp - tlsdevs, t);
ch->qid.vers = 0;
unlock(&tdlock);
poperror();
return *pp;
}
static TlsRec *
mktlsrec(void)
{
TlsRec *tr;
tr = mallocz(sizeof(*tr), 1);
if(tr == nil)
error(Enomem);
tr->state = SClosed;
tr->ref = 1;
kstrdup(&tr->user, up->user);
tr->perm = 0660;
return tr;
}
static char*
tlsstate(int s)
{
switch(s){
case SHandshake:
return "Handshaking";
case SOpen:
return "Established";
case SRClose:
return "RemoteClosed";
case SLClose:
return "LocalClosed";
case SAlert:
return "Alerting";
case SError:
return "Errored";
case SClosed:
return "Closed";
}
return "Unknown";
}
static void
freeSec(Secret *s)
{
if(s != nil){
free(s->enckey);
free(s);
}
}
static int
noenc(Secret *, uchar *, int n)
{
return n;
}
static int
rc4enc(Secret *sec, uchar *buf, int n)
{
rc4(sec->enckey, buf, n);
return n;
}
static int
tlsunpad(uchar *buf, int n, int block)
{
int pad, nn;
pad = buf[n - 1];
nn = n - 1 - pad;
if(nn <= 0 || n % block)
return -1;
while(--n > nn)
if(pad != buf[n - 1])
return -1;
return nn;
}
static int
sslunpad(uchar *buf, int n, int block)
{
int pad, nn;
pad = buf[n - 1];
nn = n - 1 - pad;
if(nn <= 0 || n % block)
return -1;
return nn;
}
static int
blockpad(uchar *buf, int n, int block)
{
int pad, nn;
nn = n + block;
nn -= nn % block;
pad = nn - (n + 1);
while(n < nn)
buf[n++] = pad;
return nn;
}
static int
des3enc(Secret *sec, uchar *buf, int n)
{
n = blockpad(buf, n, 8);
des3CBCencrypt(buf, n, sec->enckey);
return n;
}
static int
des3dec(Secret *sec, uchar *buf, int n)
{
des3CBCdecrypt(buf, n, sec->enckey);
return (*sec->unpad)(buf, n, 8);
}
static DigestState*
nomac(uchar *, ulong, uchar *, ulong, uchar *, DigestState *)
{
return nil;
}
/*
* sslmac: mac calculations for ssl 3.0 only; tls 1.0 uses the standard hmac.
*/
static DigestState*
sslmac_x(uchar *p, ulong len, uchar *key, ulong klen, uchar *digest, DigestState *s,
DigestState*(*x)(uchar*, ulong, uchar*, DigestState*), int xlen, int padlen)
{
int i;
uchar pad[48], innerdigest[20];
if(xlen > sizeof(innerdigest)
|| padlen > sizeof(pad))
return nil;
if(klen>64)
return nil;
/* first time through */
if(s == nil){
for(i=0; i<padlen; i++)
pad[i] = 0x36;
s = (*x)(key, klen, nil, nil);
s = (*x)(pad, padlen, nil, s);
if(s == nil)
return nil;
}
s = (*x)(p, len, nil, s);
if(digest == nil)
return s;
/* last time through */
for(i=0; i<padlen; i++)
pad[i] = 0x5c;
(*x)(nil, 0, innerdigest, s);
s = (*x)(key, klen, nil, nil);
s = (*x)(pad, padlen, nil, s);
(*x)(innerdigest, xlen, digest, s);
return nil;
}
static DigestState*
sslmac_sha1(uchar *p, ulong len, uchar *key, ulong klen, uchar *digest, DigestState *s)
{
return sslmac_x(p, len, key, klen, digest, s, sha1, SHA1dlen, 40);
}
static DigestState*
sslmac_md5(uchar *p, ulong len, uchar *key, ulong klen, uchar *digest, DigestState *s)
{
return sslmac_x(p, len, key, klen, digest, s, md5, MD5dlen, 48);
}
static void
sslPackMac(Secret *sec, uchar *mackey, uchar *seq, uchar *header, uchar *body, int len, uchar *mac)
{
DigestState *s;
uchar buf[11];
memmove(buf, seq, 8);
buf[8] = header[0];
buf[9] = header[3];
buf[10] = header[4];
s = (*sec->mac)(buf, 11, mackey, sec->maclen, 0, 0);
(*sec->mac)(body, len, mackey, sec->maclen, mac, s);
}
static void
tlsPackMac(Secret *sec, uchar *mackey, uchar *seq, uchar *header, uchar *body, int len, uchar *mac)
{
DigestState *s;
uchar buf[13];
memmove(buf, seq, 8);
memmove(&buf[8], header, 5);
s = (*sec->mac)(buf, 13, mackey, sec->maclen, 0, 0);
(*sec->mac)(body, len, mackey, sec->maclen, mac, s);
}
static void
put32(uchar *p, u32int x)
{
p[0] = x>>24;
p[1] = x>>16;
p[2] = x>>8;
p[3] = x;
}
static void
put64(uchar *p, vlong x)
{
put32(p, (u32int)(x >> 32));
put32(p+4, (u32int)x);
}
static void
put24(uchar *p, int x)
{
p[0] = x>>16;
p[1] = x>>8;
p[2] = x;
}
static void
put16(uchar *p, int x)
{
p[0] = x>>8;
p[1] = x;
}
static u32int
get32(uchar *p)
{
return (p[0]<<24)|(p[1]<<16)|(p[2]<<8)|p[3];
}
static int
get16(uchar *p)
{
return (p[0]<<8)|p[1];
}