ref: f11139d4c918802a87730bc14d094670ee4ce572
dir: /kern/devssl.c/
/* * devssl - secure sockets layer */ #include "u.h" #include "lib.h" #include "dat.h" #include "fns.h" #include "error.h" #include <libsec.h> typedef struct OneWay OneWay; struct OneWay { QLock q; QLock ctlq; void *state; /* encryption state */ int slen; /* hash data length */ uchar *secret; /* secret */ ulong mid; /* message id */ }; enum { /* connection states */ Sincomplete= 0, Sclear= 1, Sencrypting= 2, Sdigesting= 4, Sdigenc= Sencrypting|Sdigesting, /* encryption algorithms */ Noencryption= 0, DESCBC= 1, DESECB= 2, RC4= 3 }; typedef struct Dstate Dstate; struct Dstate { Chan *c; /* io channel */ uchar state; /* state of connection */ int ref; /* serialized by dslock for atomic destroy */ uchar encryptalg; /* encryption algorithm */ ushort blocklen; /* blocking length */ ushort diglen; /* length of digest */ DigestState *(*hf)(uchar*, ulong, uchar*, DigestState*); /* hash func */ /* for SSL format */ int max; /* maximum unpadded data per msg */ int maxpad; /* maximum padded data per msg */ /* input side */ OneWay in; Block *processed; Block *unprocessed; /* output side */ OneWay out; /* protections */ char *user; int perm; }; enum { Maxdmsg= 1<<16, Maxdstate= 512, /* max. open ssl conn's; must be a power of 2 */ }; static Lock dslock; static int dshiwat; static char *dsname[Maxdstate]; static Dstate *dstate[Maxdstate]; static char *encalgs; static char *hashalgs; enum{ Qtopdir = 1, /* top level directory */ Qprotodir, Qclonus, Qconvdir, /* directory for a conversation */ Qdata, Qctl, Qsecretin, Qsecretout, Qencalgs, Qhashalgs, }; #define TYPE(x) ((x).path & 0xf) #define CONV(x) (((x).path >> 5)&(Maxdstate-1)) #define QID(c, y) (((c)<<5) | (y)) static void ensure(Dstate*, Block**, int); static void consume(Block**, uchar*, int); static void setsecret(OneWay*, uchar*, int); static Block* encryptb(Dstate*, Block*, int); static Block* decryptb(Dstate*, Block*); static Block* digestb(Dstate*, Block*, int); static void checkdigestb(Dstate*, Block*); static Chan* buftochan(char*); static void sslhangup(Dstate*); static Dstate* dsclone(Chan *c); static void dsnew(Chan *c, Dstate **); static long sslput(Dstate *s, Block * volatile b); char *sslnames[] = { [Qclonus] "clone", [Qdata] "data", [Qctl] "ctl", [Qsecretin] "secretin", [Qsecretout] "secretout", [Qencalgs] "encalgs", [Qhashalgs] "hashalgs", }; static int sslgen(Chan *c, char *n, Dirtab *d, int nd, int s, Dir *dp) { Qid q; Dstate *ds; char name[16], *p, *nm; int ft; USED(n); USED(nd); USED(d); q.type = QTFILE; q.vers = 0; ft = TYPE(c->qid); switch(ft) { case Qtopdir: if(s == DEVDOTDOT){ q.path = QID(0, Qtopdir); q.type = QTDIR; devdir(c, q, "#D", 0, eve, 0555, dp); return 1; } if(s > 0) return -1; q.path = QID(0, Qprotodir); q.type = QTDIR; devdir(c, q, "ssl", 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 < dshiwat) { q.path = QID(s, Qconvdir); q.type = QTDIR; ds = dstate[s]; if(ds != 0) nm = ds->user; else nm = eve; if(dsname[s] == nil){ sprint(name, "%d", s); kstrdup(&dsname[s], name); } devdir(c, q, dsname[s], 0, nm, 0555, dp); return 1; } if(s > dshiwat) return -1; q.path = QID(0, Qclonus); devdir(c, q, "clone", 0, eve, 0555, dp); return 1; case Qconvdir: if(s == DEVDOTDOT){ q.path = QID(0, Qprotodir); q.type = QTDIR; devdir(c, q, "ssl", 0, eve, 0555, dp); return 1; } ds = dstate[CONV(c->qid)]; if(ds != 0) nm = ds->user; else nm = eve; switch(s) { default: return -1; case 0: q.path = QID(CONV(c->qid), Qctl); p = "ctl"; break; case 1: q.path = QID(CONV(c->qid), Qdata); p = "data"; break; case 2: q.path = QID(CONV(c->qid), Qsecretin); p = "secretin"; break; case 3: q.path = QID(CONV(c->qid), Qsecretout); p = "secretout"; break; case 4: q.path = QID(CONV(c->qid), Qencalgs); p = "encalgs"; break; case 5: q.path = QID(CONV(c->qid), Qhashalgs); p = "hashalgs"; break; } devdir(c, q, p, 0, nm, 0660, dp); return 1; case Qclonus: devdir(c, c->qid, sslnames[TYPE(c->qid)], 0, eve, 0555, dp); return 1; default: ds = dstate[CONV(c->qid)]; if(ds != 0) nm = ds->user; else nm = eve; devdir(c, c->qid, sslnames[TYPE(c->qid)], 0, nm, 0660, dp); return 1; } } static Chan* sslattach(char *spec) { Chan *c; c = devattach('D', spec); c->qid.path = QID(0, Qtopdir); c->qid.vers = 0; c->qid.type = QTDIR; return c; } static Walkqid* sslwalk(Chan *c, Chan *nc, char **name, int nname) { return devwalk(c, nc, name, nname, nil, 0, sslgen); } static int sslstat(Chan *c, uchar *db, int n) { return devstat(c, db, n, nil, 0, sslgen); } static Chan* sslopen(Chan *c, int omode) { Dstate *s, **pp; int ft; ft = TYPE(c->qid); switch(ft) { default: panic("sslopen"); case Qtopdir: case Qprotodir: case Qconvdir: if(omode != OREAD) error(Eperm); break; case Qclonus: s = dsclone(c); if(s == 0) error(Enodev); break; case Qctl: case Qdata: case Qsecretin: case Qsecretout: if(waserror()) { unlock(&dslock); nexterror(); } lock(&dslock); pp = &dstate[CONV(c->qid)]; s = *pp; if(s == 0) dsnew(c, pp); else { devpermcheck(s->user, s->perm, omode); s->ref++; } unlock(&dslock); poperror(); break; case Qencalgs: case Qhashalgs: if(omode != OREAD) error(Eperm); break; } c->mode = openmode(omode); c->flag |= COPEN; c->offset = 0; return c; } static int sslwstat(Chan *c, uchar *db, int n) { Dir *dir; Dstate *s; int m; s = dstate[CONV(c->qid)]; if(s == 0) error(Ebadusefd); if(strcmp(s->user, up->user) != 0) error(Eperm); dir = smalloc(sizeof(Dir)+n); m = convM2D(db, n, &dir[0], (char*)&dir[1]); if(m == 0){ free(dir); error(Eshortstat); } if(!emptystr(dir->uid)) kstrdup(&s->user, dir->uid); if(dir->mode != -1) s->perm = dir->mode; free(dir); return m; } static void sslclose(Chan *c) { Dstate *s; int ft; ft = TYPE(c->qid); switch(ft) { case Qctl: case Qdata: case Qsecretin: case Qsecretout: if((c->flag & COPEN) == 0) break; s = dstate[CONV(c->qid)]; if(s == 0) break; lock(&dslock); if(--s->ref > 0) { unlock(&dslock); break; } dstate[CONV(c->qid)] = 0; unlock(&dslock); if(s->user != nil) free(s->user); sslhangup(s); if(s->c) cclose(s->c); secfree(s->in.secret); secfree(s->out.secret); secfree(s->in.state); secfree(s->out.state); free(s); } } /* * make sure we have at least 'n' bytes in list 'l' */ static void ensure(Dstate *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, Maxdmsg, 0); if(bl == 0) nexterror(); *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(Dstate *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, if discard is set * dump the remainder */ static Block* qtake(Block **l, int n, int discard) { Block *nb, *b, *first; int i; first = *l; for(b = first; b; b = b->next){ i = BLEN(b); if(i == n){ if(discard){ freeblist(b->next); *l = 0; } else *l = b->next; b->next = 0; return first; } else if(i > n){ i -= n; if(discard){ freeblist(b->next); b->wp -= i; *l = 0; } else { nb = allocb(i); memmove(nb->wp, b->rp+n, i); nb->wp += i; b->wp -= i; nb->next = b->next; *l = nb; } b->next = 0; if(BLEN(b) < 0) panic("qtake"); return first; } else n -= i; if(BLEN(b) < 0) panic("qtake"); } *l = 0; return first; } /* * We can't let Eintr's lose data since the program * doing the read may be able to handle it. The only * places Eintr is possible is during the read's in consume. * Therefore, we make sure we can always put back the bytes * consumed before the last ensure. */ static Block* sslbread(Chan *c, long n, ulong o) { Dstate * volatile s; Block *b; uchar consumed[3], *p; int toconsume; int len, pad; USED(o); s = dstate[CONV(c->qid)]; if(s == 0) panic("sslbread"); if(s->state == Sincomplete) error(Ebadusefd); qlock(&s->in.q); if(waserror()){ qunlock(&s->in.q); nexterror(); } if(s->processed == 0){ /* * Read in the whole message. Until we've got it all, * it stays on s->unprocessed, so that if we get Eintr, * we'll pick up where we left off. */ ensure(s, &s->unprocessed, 3); s->unprocessed = pullupblock(s->unprocessed, 2); p = s->unprocessed->rp; if(p[0] & 0x80){ len = ((p[0] & 0x7f)<<8) | p[1]; ensure(s, &s->unprocessed, len); pad = 0; toconsume = 2; } else { s->unprocessed = pullupblock(s->unprocessed, 3); len = ((p[0] & 0x3f)<<8) | p[1]; pad = p[2]; if(pad > len){ print("pad %d buf len %d\n", pad, len); error("bad pad in ssl message"); } toconsume = 3; } ensure(s, &s->unprocessed, toconsume+len); /* skip header */ consume(&s->unprocessed, consumed, toconsume); /* grab the next message and decode/decrypt it */ b = qtake(&s->unprocessed, len, 0); if(blocklen(b) != len) print("devssl: sslbread got wrong count %d != %d", blocklen(b), len); if(waserror()){ qunlock(&s->in.ctlq); if(b != nil) freeb(b); nexterror(); } qlock(&s->in.ctlq); switch(s->state){ case Sencrypting: if(b == nil) error("ssl message too short (encrypting)"); b = decryptb(s, b); break; case Sdigesting: b = pullupblock(b, s->diglen); if(b == nil) error("ssl message too short (digesting)"); checkdigestb(s, b); pullblock(&b, s->diglen); len -= s->diglen; break; case Sdigenc: b = decryptb(s, b); b = pullupblock(b, s->diglen); if(b == nil) error("ssl message too short (dig+enc)"); checkdigestb(s, b); pullblock(&b, s->diglen); len -= s->diglen; break; } /* remove pad */ if(pad) s->processed = qtake(&b, len - pad, 1); else s->processed = b; b = nil; s->in.mid++; qunlock(&s->in.ctlq); poperror(); } /* return at most what was asked for */ b = qtake(&s->processed, n, 0); qunlock(&s->in.q); poperror(); return b; } static long sslread(Chan *c, void *a, long n, vlong off) { Block * volatile b; Block *nb; uchar *va; int i; char buf[128]; ulong offset = off; int ft; if(c->qid.type & QTDIR) return devdirread(c, a, n, 0, 0, sslgen); ft = TYPE(c->qid); switch(ft) { default: error(Ebadusefd); case Qctl: ft = CONV(c->qid); sprint(buf, "%d", ft); return readstr(offset, a, n, buf); case Qdata: b = sslbread(c, n, offset); break; case Qencalgs: return readstr(offset, a, n, encalgs); break; case Qhashalgs: return readstr(offset, a, n, hashalgs); break; } 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; } static long sslbwrite(Chan *c, Block *b, ulong o) { Dstate * volatile s; long rv; USED(o); s = dstate[CONV(c->qid)]; if(s == nil) panic("sslbwrite"); if(s->state == Sincomplete){ freeb(b); error(Ebadusefd); } /* lock so split writes won't interleave */ if(waserror()){ qunlock(&s->out.q); nexterror(); } qlock(&s->out.q); rv = sslput(s, b); poperror(); qunlock(&s->out.q); return rv; } /* * use SSL record format, add in count, digest and/or encrypt. * the write is interruptable. if it is interrupted, we'll * get out of sync with the far side. not much we can do about * it since we don't know if any bytes have been written. */ static long sslput(Dstate *s, Block * volatile b) { Block *nb; int h, n, m, pad, rv; uchar *p; int offset; if(waserror()){ if(b != nil) freeb(b); nexterror(); } rv = 0; while(b != nil){ m = n = BLEN(b); h = s->diglen + 2; /* trim to maximum block size */ pad = 0; if(m > s->max){ m = s->max; } else if(s->blocklen != 1){ pad = (m + s->diglen)%s->blocklen; if(pad){ if(m > s->maxpad){ pad = 0; m = s->maxpad; } else { pad = s->blocklen - pad; h++; } } } rv += m; if(m != n){ nb = allocb(m + h + pad); memmove(nb->wp + h, b->rp, m); nb->wp += m + h; b->rp += m; } else { /* add header space */ nb = padblock(b, h); b = 0; } m += s->diglen; /* SSL style count */ if(pad){ nb = padblock(nb, -pad); prng(nb->wp, pad); nb->wp += pad; m += pad; p = nb->rp; p[0] = (m>>8); p[1] = m; p[2] = pad; offset = 3; } else { p = nb->rp; p[0] = (m>>8) | 0x80; p[1] = m; offset = 2; } switch(s->state){ case Sencrypting: nb = encryptb(s, nb, offset); break; case Sdigesting: nb = digestb(s, nb, offset); break; case Sdigenc: nb = digestb(s, nb, offset); nb = encryptb(s, nb, offset); break; } s->out.mid++; m = BLEN(nb); devtab[s->c->type]->bwrite(s->c, nb, s->c->offset); s->c->offset += m; } poperror(); return rv; } static void setsecret(OneWay *w, uchar *secret, int n) { secfree(w->secret); w->secret = secalloc(n); memmove(w->secret, secret, n); w->slen = n; } static void initDESkey(OneWay *w) { secfree(w->state); w->state = secalloc(sizeof(DESstate)); if(w->slen >= 16) setupDESstate(w->state, w->secret, w->secret+8); else if(w->slen >= 8) setupDESstate(w->state, w->secret, 0); else error("secret too short"); } /* * 40 bit DES is the same as 56 bit DES. However, * 16 bits of the key are masked to zero. */ static void initDESkey_40(OneWay *w) { uchar key[8]; if(w->slen >= 8){ memmove(key, w->secret, 8); key[0] &= 0x0f; key[2] &= 0x0f; key[4] &= 0x0f; key[6] &= 0x0f; } initDESkey(w); } static void initRC4key(OneWay *w) { secfree(w->state); w->state = secalloc(sizeof(RC4state)); setupRC4state(w->state, w->secret, w->slen); } /* * 40 bit RC4 is the same as n-bit RC4. However, * we ignore all but the first 40 bits of the key. */ static void initRC4key_40(OneWay *w) { if(w->slen > 5) w->slen = 5; initRC4key(w); } /* * 128 bit RC4 is the same as n-bit RC4. However, * we ignore all but the first 128 bits of the key. */ static void initRC4key_128(OneWay *w) { if(w->slen > 16) w->slen = 16; initRC4key(w); } typedef struct Hashalg Hashalg; struct Hashalg { char *name; int diglen; DigestState *(*hf)(uchar*, ulong, uchar*, DigestState*); }; Hashalg hashtab[] = { { "md5", MD5dlen, md5, }, { "sha1", SHA1dlen, sha1, }, { "sha", SHA1dlen, sha1, }, { 0 } }; static int parsehashalg(char *p, Dstate *s) { Hashalg *ha; for(ha = hashtab; ha->name; ha++){ if(strcmp(p, ha->name) == 0){ s->hf = ha->hf; s->diglen = ha->diglen; s->state &= ~Sclear; s->state |= Sdigesting; return 0; } } return -1; } typedef struct Encalg Encalg; struct Encalg { char *name; int blocklen; int alg; void (*keyinit)(OneWay*); }; static Encalg encrypttab[] = { { "descbc", 8, DESCBC, initDESkey, }, /* DEPRECATED -- use des_56_cbc */ { "desecb", 8, DESECB, initDESkey, }, /* DEPRECATED -- use des_56_ecb */ { "des_56_cbc", 8, DESCBC, initDESkey, }, { "des_56_ecb", 8, DESECB, initDESkey, }, { "des_40_cbc", 8, DESCBC, initDESkey_40, }, { "des_40_ecb", 8, DESECB, initDESkey_40, }, { "rc4", 1, RC4, initRC4key_40, }, /* DEPRECATED -- use rc4_X */ { "rc4_256", 1, RC4, initRC4key, }, { "rc4_128", 1, RC4, initRC4key_128, }, { "rc4_40", 1, RC4, initRC4key_40, }, { 0 } }; static int parseencryptalg(char *p, Dstate *s) { Encalg *ea; for(ea = encrypttab; ea->name; ea++){ if(strcmp(p, ea->name) == 0){ s->encryptalg = ea->alg; s->blocklen = ea->blocklen; (*ea->keyinit)(&s->in); (*ea->keyinit)(&s->out); s->state &= ~Sclear; s->state |= Sencrypting; return 0; } } return -1; } enum { Cfd, Calg, Csin, Csout, }; static Cmdtab sslcmds[] = { {Cfd, "fd", 2 }, {Calg, "alg", 0 }, {Csin, "secretin", 2 }, {Csout, "secretout", 2 }, }; static long sslwrite(Chan *c, void *a, long n, vlong o) { Dstate * volatile s; Block * volatile b; int m, t, i; char *p, *e; uchar *x; Cmdbuf *cb; Cmdtab *ct; USED(o); s = dstate[CONV(c->qid)]; if(s == 0) panic("sslwrite"); t = TYPE(c->qid); if(t == Qdata){ if(s->state == Sincomplete) error(Ebadusefd); /* lock should a write gets split over multiple records */ if(waserror()){ qunlock(&s->out.q); nexterror(); } qlock(&s->out.q); p = a; e = p + n; do { m = e - p; if(m > s->max) m = s->max; b = allocb(m); if(waserror()){ freeb(b); nexterror(); } memmove(b->wp, p, m); poperror(); b->wp += m; sslput(s, b); p += m; } while(p < e); poperror(); qunlock(&s->out.q); return n; } /* mutex with operations using what we're about to change */ if(waserror()){ qunlock(&s->in.ctlq); qunlock(&s->out.q); nexterror(); } qlock(&s->in.ctlq); qlock(&s->out.q); switch(t){ default: panic("sslwrite"); case Qsecretin: setsecret(&s->in, a, n); goto out; case Qsecretout: setsecret(&s->out, a, n); goto out; case Qctl: break; } cb = parsecmd(a, n); if(waserror()){ free(cb); nexterror(); } ct = lookupcmd(cb, sslcmds, nelem(sslcmds)); switch(ct->index){ case Cfd: s->c = buftochan(cb->f[1]); /* default is clear (msg delimiters only) */ s->state = Sclear; s->blocklen = 1; s->diglen = 0; s->maxpad = s->max = (1<<15) - s->diglen - 1; s->in.mid = 0; s->out.mid = 0; break; case Calg: if(cb->nf < 2) cmderror(cb, "no algorithms"); s->blocklen = 1; s->diglen = 0; if(s->c == 0) error("must set fd before algorithm"); s->state = Sclear; s->maxpad = s->max = (1<<15) - s->diglen - 1; if(strcmp(cb->f[1], "clear") == 0) break; if(s->in.secret && s->out.secret == 0) setsecret(&s->out, s->in.secret, s->in.slen); if(s->out.secret && s->in.secret == 0) setsecret(&s->in, s->out.secret, s->out.slen); if(s->in.secret == 0 || s->out.secret == 0) error("algorithm but no secret"); s->hf = 0; s->encryptalg = Noencryption; s->blocklen = 1; for(i=1; i<cb->nf; i++){ p = cb->f[i]; if(parsehashalg(p, s) < 0) if(parseencryptalg(p, s) < 0) error("bad algorithm"); } if(s->hf == 0 && s->encryptalg == Noencryption) error("bad algorithm"); if(s->blocklen != 1){ s->max = (1<<15) - s->diglen - 1; s->max -= s->max % s->blocklen; s->maxpad = (1<<14) - s->diglen - 1; s->maxpad -= s->maxpad % s->blocklen; } else s->maxpad = s->max = (1<<15) - s->diglen - 1; break; case Csin: p = cb->f[1]; m = (strlen(p)*3)/2 + 1; x = secalloc(m); t = dec64(x, m, p, strlen(p)); memset(p, 0, strlen(p)); if(t <= 0){ secfree(x); error(Ebadarg); } setsecret(&s->in, x, t); secfree(x); break; case Csout: p = cb->f[1]; m = (strlen(p)*3)/2 + 1; x = secalloc(m); t = dec64(x, m, p, strlen(p)); memset(p, 0, strlen(p)); if(t <= 0){ secfree(x); error(Ebadarg); } setsecret(&s->out, x, t); secfree(x); break; } poperror(); free(cb); out: qunlock(&s->in.ctlq); qunlock(&s->out.q); poperror(); return n; } static void sslinit(void) { struct Encalg *e; struct Hashalg *h; int n; char *cp; 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 ssldevtab = { 'D', "ssl", devreset, sslinit, devshutdown, sslattach, sslwalk, sslstat, sslopen, devcreate, sslclose, sslread, sslbread, sslwrite, sslbwrite, devremove, sslwstat, }; static Block* encryptb(Dstate *s, Block *b, int offset) { uchar *p, *ep, *p2, *ip, *eip; DESstate *ds; switch(s->encryptalg){ case DESECB: ds = s->out.state; ep = b->rp + BLEN(b); for(p = b->rp + offset; p < ep; p += 8) block_cipher(ds->expanded, p, 0); break; case DESCBC: ds = s->out.state; ep = b->rp + BLEN(b); for(p = b->rp + offset; p < ep; p += 8){ p2 = p; ip = ds->ivec; for(eip = ip+8; ip < eip; ) *p2++ ^= *ip++; block_cipher(ds->expanded, p, 0); memmove(ds->ivec, p, 8); } break; case RC4: rc4(s->out.state, b->rp + offset, BLEN(b) - offset); break; } return b; } static Block* decryptb(Dstate *s, Block *bin) { Block *b, **l; uchar *p, *ep, *tp, *ip, *eip; DESstate *ds; uchar tmp[8]; int i; l = &bin; for(b = bin; b; b = b->next){ /* make sure we have a multiple of s->blocklen */ if(s->blocklen > 1){ i = BLEN(b); if(i % s->blocklen){ *l = b = pullupblock(b, i + s->blocklen - (i%s->blocklen)); if(b == 0) error("ssl encrypted message too short"); } } l = &b->next; /* decrypt */ switch(s->encryptalg){ case DESECB: ds = s->in.state; ep = b->rp + BLEN(b); for(p = b->rp; p < ep; p += 8) block_cipher(ds->expanded, p, 1); break; case DESCBC: ds = s->in.state; ep = b->rp + BLEN(b); for(p = b->rp; p < ep;){ memmove(tmp, p, 8); block_cipher(ds->expanded, p, 1); tp = tmp; ip = ds->ivec; for(eip = ip+8; ip < eip; ){ *p++ ^= *ip; *ip++ = *tp++; } } break; case RC4: rc4(s->in.state, b->rp, BLEN(b)); break; } } return bin; } static Block* digestb(Dstate *s, Block *b, int offset) { uchar *p; DigestState ss; uchar msgid[4]; ulong n, h; OneWay *w; w = &s->out; memset(&ss, 0, sizeof(ss)); h = s->diglen + offset; n = BLEN(b) - h; /* hash secret + message */ (*s->hf)(w->secret, w->slen, 0, &ss); (*s->hf)(b->rp + h, n, 0, &ss); /* hash message id */ p = msgid; n = w->mid; *p++ = n>>24; *p++ = n>>16; *p++ = n>>8; *p = n; (*s->hf)(msgid, 4, b->rp + offset, &ss); return b; } static void checkdigestb(Dstate *s, Block *bin) { uchar *p; DigestState ss; uchar msgid[4]; int n, h; OneWay *w; uchar digest[128]; Block *b; w = &s->in; memset(&ss, 0, sizeof(ss)); /* hash secret */ (*s->hf)(w->secret, w->slen, 0, &ss); /* hash message */ h = s->diglen; for(b = bin; b; b = b->next){ n = BLEN(b) - h; if(n < 0) panic("checkdigestb"); (*s->hf)(b->rp + h, n, 0, &ss); h = 0; } /* hash message id */ p = msgid; n = w->mid; *p++ = n>>24; *p++ = n>>16; *p++ = n>>8; *p = n; (*s->hf)(msgid, 4, digest, &ss); if(tsmemcmp(digest, bin->rp, s->diglen) != 0) error("bad digest"); } /* 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, ORDWR, 1, 1); /* error check and inc ref */ if(devtab[c->type] == &ssldevtab){ cclose(c); error("cannot ssl encrypt devssl files"); } return c; } /* hand up a digest connection */ static void sslhangup(Dstate *s) { Block *b; qlock(&s->in.q); for(b = s->processed; b; b = s->processed){ s->processed = b->next; freeb(b); } if(s->unprocessed){ freeb(s->unprocessed); s->unprocessed = 0; } s->state = Sincomplete; qunlock(&s->in.q); } static Dstate* dsclone(Chan *ch) { int i; Dstate *ret; if(waserror()) { unlock(&dslock); nexterror(); } lock(&dslock); ret = nil; for(i=0; i<Maxdstate; i++){ if(dstate[i] == nil){ dsnew(ch, &dstate[i]); ret = dstate[i]; break; } } unlock(&dslock); poperror(); return ret; } static void dsnew(Chan *ch, Dstate **pp) { Dstate *s; int t; *pp = s = malloc(sizeof(*s)); if(!s) error(Enomem); if(pp - dstate >= dshiwat) dshiwat++; memset(s, 0, sizeof(*s)); s->state = Sincomplete; s->ref = 1; kstrdup(&s->user, up->user); s->perm = 0660; t = TYPE(ch->qid); if(t == Qclonus) t = Qctl; ch->qid.path = QID(pp - dstate, t); ch->qid.vers = 0; }