X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/e03299cbdda650047f609b0545e1790c67418b55..HEAD:/ssh.c diff --git a/ssh.c b/ssh.c index fa400c34..9eed54dc 100644 --- a/ssh.c +++ b/ssh.c @@ -460,14 +460,14 @@ struct Packet; static struct Packet *ssh1_pkt_init(int pkt_type); static struct Packet *ssh2_pkt_init(int pkt_type); static void ssh_pkt_ensure(struct Packet *, int length); -static void ssh_pkt_adddata(struct Packet *, void *data, int len); +static void ssh_pkt_adddata(struct Packet *, const void *data, int len); static void ssh_pkt_addbyte(struct Packet *, unsigned char value); static void ssh2_pkt_addbool(struct Packet *, unsigned char value); static void ssh_pkt_adduint32(struct Packet *, unsigned long value); static void ssh_pkt_addstring_start(struct Packet *); -static void ssh_pkt_addstring_str(struct Packet *, char *data); -static void ssh_pkt_addstring_data(struct Packet *, char *data, int len); -static void ssh_pkt_addstring(struct Packet *, char *data); +static void ssh_pkt_addstring_str(struct Packet *, const char *data); +static void ssh_pkt_addstring_data(struct Packet *, const char *data, int len); +static void ssh_pkt_addstring(struct Packet *, const char *data); static unsigned char *ssh2_mpint_fmt(Bignum b, int *len); static void ssh1_pkt_addmp(struct Packet *, Bignum b); static void ssh2_pkt_addmp(struct Packet *, Bignum b); @@ -525,7 +525,7 @@ static void ssh_channel_destroy(struct ssh_channel *c); const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss }; const static struct ssh_mac *macs[] = { - &ssh_hmac_sha1, &ssh_hmac_sha1_96, &ssh_hmac_md5 + &ssh_hmac_sha256, &ssh_hmac_sha1, &ssh_hmac_sha1_96, &ssh_hmac_md5 }; const static struct ssh_mac *buggymacs[] = { &ssh_hmac_sha1_buggy, &ssh_hmac_sha1_96_buggy, &ssh_hmac_md5 @@ -589,14 +589,6 @@ struct outstanding_channel_request { }; /* - * little structure to keep track of outstanding WINDOW_ADJUSTs - */ -struct winadj { - struct winadj *next; - unsigned size; -}; - -/* * 2-3-4 tree storing channels. */ struct ssh_channel { @@ -674,6 +666,7 @@ struct ssh_channel { unsigned char *message; unsigned char msglen[4]; unsigned lensofar, totallen; + int outstanding_requests; } a; struct ssh_x11_channel { Socket s; @@ -779,7 +772,7 @@ static int ssh_do_close(Ssh ssh, int notify_exit); static unsigned long ssh_pkt_getuint32(struct Packet *pkt); static int ssh2_pkt_getbool(struct Packet *pkt); static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length); -static void ssh2_timer(void *ctx, long now); +static void ssh2_timer(void *ctx, unsigned long now); static void do_ssh2_transport(Ssh ssh, void *vin, int inlen, struct Packet *pktin); static void ssh2_msg_unexpected(Ssh ssh, struct Packet *pktin); @@ -988,7 +981,7 @@ struct ssh_tag { unsigned long incoming_data_size, outgoing_data_size, deferred_data_size; unsigned long max_data_size; int kex_in_progress; - long next_rekey, last_rekey; + unsigned long next_rekey, last_rekey; char *deferred_rekey_reason; /* points to STATIC string; don't free */ /* @@ -1456,7 +1449,8 @@ static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen) /* See if that gives us a valid packet. */ if (ssh->scmac->verresult(ssh->sc_mac_ctx, st->pktin->data + st->packetlen) && - (st->len = GET_32BIT(st->pktin->data)) + 4 == st->packetlen) + ((st->len = toint(GET_32BIT(st->pktin->data))) == + st->packetlen-4)) break; if (st->packetlen >= OUR_V2_PACKETLIMIT) { bombout(("No valid incoming packet found")); @@ -1489,7 +1483,7 @@ static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen) /* * Now get the length figure. */ - st->len = GET_32BIT(st->pktin->data); + st->len = toint(GET_32BIT(st->pktin->data)); /* * _Completely_ silly lengths should be stomped on before they @@ -1835,7 +1829,7 @@ static void ssh_pkt_ensure(struct Packet *pkt, int length) if (body) pkt->body = pkt->data + offset; } } -static void ssh_pkt_adddata(struct Packet *pkt, void *data, int len) +static void ssh_pkt_adddata(struct Packet *pkt, const void *data, int len) { if (pkt->logmode != PKTLOG_EMIT) { pkt->nblanks++; @@ -1869,17 +1863,18 @@ static void ssh_pkt_addstring_start(struct Packet *pkt) ssh_pkt_adduint32(pkt, 0); pkt->savedpos = pkt->length; } -static void ssh_pkt_addstring_str(struct Packet *pkt, char *data) +static void ssh_pkt_addstring_str(struct Packet *pkt, const char *data) { ssh_pkt_adddata(pkt, data, strlen(data)); PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos); } -static void ssh_pkt_addstring_data(struct Packet *pkt, char *data, int len) +static void ssh_pkt_addstring_data(struct Packet *pkt, const char *data, + int len) { ssh_pkt_adddata(pkt, data, len); PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos); } -static void ssh_pkt_addstring(struct Packet *pkt, char *data) +static void ssh_pkt_addstring(struct Packet *pkt, const char *data) { ssh_pkt_addstring_start(pkt); ssh_pkt_addstring_str(pkt, data); @@ -2320,7 +2315,7 @@ static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length) *length = 0; if (pkt->length - pkt->savedpos < 4) return; - len = GET_32BIT(pkt->body + pkt->savedpos); + len = toint(GET_32BIT(pkt->body + pkt->savedpos)); if (len < 0) return; *length = len; @@ -2404,7 +2399,7 @@ static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt, * See if this is in fact an ssh-rsa signature and a buggy * server; otherwise we can just do this the easy way. */ - if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) && + if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) && pkblob_len > 4+7+4 && (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) { int pos, len, siglen; @@ -2413,8 +2408,15 @@ static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt, */ pos = 4+7; /* skip over "ssh-rsa" */ - pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */ - len = GET_32BIT(pkblob+pos); /* find length of modulus */ + len = toint(GET_32BIT(pkblob+pos)); /* get length of exponent */ + if (len < 0 || len > pkblob_len - pos - 4) + goto give_up; + pos += 4 + len; /* skip over exponent */ + if (pkblob_len - pos < 4) + goto give_up; + len = toint(GET_32BIT(pkblob+pos)); /* find length of modulus */ + if (len < 0 || len > pkblob_len - pos - 4) + goto give_up; pos += 4; /* find modulus itself */ while (len > 0 && pkblob[pos] == 0) len--, pos++; @@ -2424,7 +2426,11 @@ static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt, * Now find the signature integer. */ pos = 4+7; /* skip over "ssh-rsa" */ - siglen = GET_32BIT(sigblob+pos); + if (sigblob_len < pos+4) + goto give_up; + siglen = toint(GET_32BIT(sigblob+pos)); + if (siglen != sigblob_len - pos - 4) + goto give_up; /* debug(("signature length is %d\n", siglen)); */ if (len != siglen) { @@ -2446,7 +2452,10 @@ static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt, return; } - /* Otherwise fall through and do it the easy way. */ + /* Otherwise fall through and do it the easy way. We also come + * here as a fallback if we discover above that the key blob + * is misformatted in some way. */ + give_up:; } ssh2_pkt_addstring_start(pkt); @@ -3209,6 +3218,7 @@ static void ssh_agentf_callback(void *cv, void *reply, int replylen) Ssh ssh = c->ssh; void *sentreply = reply; + c->u.a.outstanding_requests--; if (!sentreply) { /* Fake SSH_AGENT_FAILURE. */ sentreply = "\0\0\0\1\5"; @@ -3228,6 +3238,12 @@ static void ssh_agentf_callback(void *cv, void *reply, int replylen) } if (reply) sfree(reply); + /* + * If we've already seen an incoming EOF but haven't sent an + * outgoing one, this may be the moment to send it. + */ + if (c->u.a.outstanding_requests == 0 && (c->closes & CLOSES_RCVD_EOF)) + sshfwd_write_eof(c); } /* @@ -3271,7 +3287,6 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, { int i, j, ret; unsigned char cookie[8], *ptr; - struct RSAKey servkey, hostkey; struct MD5Context md5c; struct do_ssh1_login_state { int crLine; @@ -3299,6 +3314,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int commentlen; int dlgret; Filename *keyfile; + struct RSAKey servkey, hostkey; }; crState(do_ssh1_login_state); @@ -3321,8 +3337,8 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, } memcpy(cookie, ptr, 8); - if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) || - !ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) { + if (!ssh1_pkt_getrsakey(pktin, &s->servkey, &s->keystr1) || + !ssh1_pkt_getrsakey(pktin, &s->hostkey, &s->keystr2)) { bombout(("Failed to read SSH-1 public keys from public key packet")); crStop(0); } @@ -3334,9 +3350,9 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, char logmsg[80]; logevent("Host key fingerprint is:"); strcpy(logmsg, " "); - hostkey.comment = NULL; + s->hostkey.comment = NULL; rsa_fingerprint(logmsg + strlen(logmsg), - sizeof(logmsg) - strlen(logmsg), &hostkey); + sizeof(logmsg) - strlen(logmsg), &s->hostkey); logevent(logmsg); } @@ -3351,8 +3367,8 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER; MD5Init(&md5c); - MD5Update(&md5c, s->keystr2, hostkey.bytes); - MD5Update(&md5c, s->keystr1, servkey.bytes); + MD5Update(&md5c, s->keystr2, s->hostkey.bytes); + MD5Update(&md5c, s->keystr1, s->servkey.bytes); MD5Update(&md5c, cookie, 8); MD5Final(s->session_id, &md5c); @@ -3362,13 +3378,14 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, /* * Verify that the `bits' and `bytes' parameters match. */ - if (hostkey.bits > hostkey.bytes * 8 || - servkey.bits > servkey.bytes * 8) { + if (s->hostkey.bits > s->hostkey.bytes * 8 || + s->servkey.bits > s->servkey.bytes * 8) { bombout(("SSH-1 public keys were badly formatted")); crStop(0); } - s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes); + s->len = (s->hostkey.bytes > s->servkey.bytes ? + s->hostkey.bytes : s->servkey.bytes); s->rsabuf = snewn(s->len, unsigned char); @@ -3379,11 +3396,11 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, /* * First format the key into a string. */ - int len = rsastr_len(&hostkey); + int len = rsastr_len(&s->hostkey); char fingerprint[100]; char *keystr = snewn(len, char); - rsastr_fmt(keystr, &hostkey); - rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey); + rsastr_fmt(keystr, &s->hostkey); + rsa_fingerprint(fingerprint, sizeof(fingerprint), &s->hostkey); ssh_set_frozen(ssh, 1); s->dlgret = verify_ssh_host_key(ssh->frontend, @@ -3417,14 +3434,14 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, s->rsabuf[i] ^= s->session_id[i]; } - if (hostkey.bytes > servkey.bytes) { - ret = rsaencrypt(s->rsabuf, 32, &servkey); + if (s->hostkey.bytes > s->servkey.bytes) { + ret = rsaencrypt(s->rsabuf, 32, &s->servkey); if (ret) - ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey); + ret = rsaencrypt(s->rsabuf, s->servkey.bytes, &s->hostkey); } else { - ret = rsaencrypt(s->rsabuf, 32, &hostkey); + ret = rsaencrypt(s->rsabuf, 32, &s->hostkey); if (ret) - ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey); + ret = rsaencrypt(s->rsabuf, s->hostkey.bytes, &s->servkey); } if (!ret) { bombout(("SSH-1 public key encryptions failed due to bad formatting")); @@ -3527,21 +3544,21 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, ssh->crcda_ctx = crcda_make_context(); logevent("Installing CRC compensation attack detector"); - if (servkey.modulus) { - sfree(servkey.modulus); - servkey.modulus = NULL; + if (s->servkey.modulus) { + sfree(s->servkey.modulus); + s->servkey.modulus = NULL; } - if (servkey.exponent) { - sfree(servkey.exponent); - servkey.exponent = NULL; + if (s->servkey.exponent) { + sfree(s->servkey.exponent); + s->servkey.exponent = NULL; } - if (hostkey.modulus) { - sfree(hostkey.modulus); - hostkey.modulus = NULL; + if (s->hostkey.modulus) { + sfree(s->hostkey.modulus); + s->hostkey.modulus = NULL; } - if (hostkey.exponent) { - sfree(hostkey.exponent); - hostkey.exponent = NULL; + if (s->hostkey.exponent) { + sfree(s->hostkey.exponent); + s->hostkey.exponent = NULL; } crWaitUntil(pktin); @@ -3676,7 +3693,12 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, if (s->response && s->responselen >= 5 && s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) { s->p = s->response + 5; - s->nkeys = GET_32BIT(s->p); + s->nkeys = toint(GET_32BIT(s->p)); + if (s->nkeys < 0) { + logeventf(ssh, "Pageant reported negative key count %d", + s->nkeys); + s->nkeys = 0; + } s->p += 4; logeventf(ssh, "Pageant has %d SSH-1 keys", s->nkeys); for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) { @@ -3686,22 +3708,23 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int n, ok = FALSE; do { /* do while (0) to make breaking easy */ n = ssh1_read_bignum - (s->p, s->responselen-(s->p-s->response), + (s->p, toint(s->responselen-(s->p-s->response)), &s->key.exponent); if (n < 0) break; s->p += n; n = ssh1_read_bignum - (s->p, s->responselen-(s->p-s->response), + (s->p, toint(s->responselen-(s->p-s->response)), &s->key.modulus); if (n < 0) - break; + break; s->p += n; if (s->responselen - (s->p-s->response) < 4) break; - s->commentlen = GET_32BIT(s->p); + s->commentlen = toint(GET_32BIT(s->p)); s->p += 4; - if (s->responselen - (s->p-s->response) < + if (s->commentlen < 0 || + toint(s->responselen - (s->p-s->response)) < s->commentlen) break; s->commentp = (char *)s->p; @@ -4618,9 +4641,9 @@ static void ssh_setup_portfwd(Ssh ssh, Conf *conf) /* XXX: rport_acceptall may not represent * what was used to open the original connection, * since it's reconfigurable. */ - ssh2_pkt_addstring(pktout, "0.0.0.0"); + ssh2_pkt_addstring(pktout, ""); } else { - ssh2_pkt_addstring(pktout, "127.0.0.1"); + ssh2_pkt_addstring(pktout, "localhost"); } ssh2_pkt_adduint32(pktout, epf->sport); ssh2_pkt_send(ssh, pktout); @@ -4733,9 +4756,9 @@ static void ssh_setup_portfwd(Ssh ssh, Conf *conf) if (epf->saddr) { ssh2_pkt_addstring(pktout, epf->saddr); } else if (conf_get_int(conf, CONF_rport_acceptall)) { - ssh2_pkt_addstring(pktout, "0.0.0.0"); + ssh2_pkt_addstring(pktout, ""); } else { - ssh2_pkt_addstring(pktout, "127.0.0.1"); + ssh2_pkt_addstring(pktout, "localhost"); } ssh2_pkt_adduint32(pktout, epf->sport); ssh2_pkt_send(ssh, pktout); @@ -4835,6 +4858,7 @@ static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin) c->type = CHAN_AGENT; /* identify channel type */ c->u.a.lensofar = 0; c->u.a.message = NULL; + c->u.a.outstanding_requests = 0; add234(ssh->channels, c); send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION, PKT_INT, c->remoteid, PKT_INT, c->localid, @@ -4846,14 +4870,11 @@ static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin) { /* Remote side is trying to open a channel to talk to a * forwarded port. Give them back a local channel number. */ - struct ssh_channel *c; struct ssh_rportfwd pf, *pfp; int remoteid; int hostsize, port; char *host; const char *e; - c = snew(struct ssh_channel); - c->ssh = ssh; remoteid = ssh_pkt_getuint32(pktin); ssh_pkt_getstring(pktin, &host, &hostsize); @@ -4872,6 +4893,9 @@ static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin) send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE, PKT_INT, remoteid, PKT_END); } else { + struct ssh_channel *c = snew(struct ssh_channel); + c->ssh = ssh; + logeventf(ssh, "Received remote port open request for %s:%d", pf.dhost, port); e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port, @@ -5060,6 +5084,7 @@ static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin) if (c->u.a.lensofar == c->u.a.totallen) { void *reply; int replylen; + c->u.a.outstanding_requests++; if (agent_query(c->u.a.message, c->u.a.totallen, &reply, &replylen, @@ -5885,6 +5910,16 @@ static void do_ssh2_transport(Ssh ssh, void *vin, int inlen, ssh_pkt_getstring(pktin, &str, &len); /* server->client language */ s->ignorepkt = ssh2_pkt_getbool(pktin) && !s->guessok; + ssh->exhash = ssh->kex->hash->init(); + hash_string(ssh->kex->hash, ssh->exhash, ssh->v_c, strlen(ssh->v_c)); + hash_string(ssh->kex->hash, ssh->exhash, ssh->v_s, strlen(ssh->v_s)); + hash_string(ssh->kex->hash, ssh->exhash, + s->our_kexinit, s->our_kexinitlen); + sfree(s->our_kexinit); + if (pktin->length > 5) + hash_string(ssh->kex->hash, ssh->exhash, + pktin->data + 5, pktin->length - 5); + if (s->warn_kex) { ssh_set_frozen(ssh, 1); s->dlgret = askalg(ssh->frontend, "key-exchange algorithm", @@ -5959,16 +5994,6 @@ static void do_ssh2_transport(Ssh ssh, void *vin, int inlen, } } - ssh->exhash = ssh->kex->hash->init(); - hash_string(ssh->kex->hash, ssh->exhash, ssh->v_c, strlen(ssh->v_c)); - hash_string(ssh->kex->hash, ssh->exhash, ssh->v_s, strlen(ssh->v_s)); - hash_string(ssh->kex->hash, ssh->exhash, - s->our_kexinit, s->our_kexinitlen); - sfree(s->our_kexinit); - if (pktin->length > 5) - hash_string(ssh->kex->hash, ssh->exhash, - pktin->data + 5, pktin->length - 5); - if (s->ignorepkt) /* first_kex_packet_follows */ crWaitUntilV(pktin); /* Ignore packet */ } @@ -6580,6 +6605,21 @@ static void ssh2_channel_init(struct ssh_channel *c) } /* + * Construct the common parts of a CHANNEL_OPEN. + */ +static struct Packet *ssh2_chanopen_init(struct ssh_channel *c, char *type) +{ + struct Packet *pktout; + + pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); + ssh2_pkt_addstring(pktout, type); + ssh2_pkt_adduint32(pktout, c->localid); + ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */ + ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */ + return pktout; +} + +/* * CHANNEL_FAILURE doesn't come with any indication of what message * caused it, so we have to keep track of the outstanding * CHANNEL_REQUESTs ourselves. @@ -6840,6 +6880,7 @@ static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin) if (c->u.a.lensofar == c->u.a.totallen) { void *reply; int replylen; + c->u.a.outstanding_requests++; if (agent_query(c->u.a.message, c->u.a.totallen, &reply, &replylen, @@ -6978,8 +7019,10 @@ static void ssh2_channel_got_eof(struct ssh_channel *c) if (c->type == CHAN_X11) { x11_send_eof(c->u.x11.s); } else if (c->type == CHAN_AGENT) { - /* Manufacture an outgoing EOF in response to the incoming one. */ - sshfwd_write_eof(c); + if (c->u.a.outstanding_requests == 0) { + /* Manufacture an outgoing EOF in response to the incoming one. */ + sshfwd_write_eof(c); + } } else if (c->type == CHAN_SOCKDATA) { pfd_send_eof(c->u.pfd.s); } else if (c->type == CHAN_MAINSESSION) { @@ -7052,6 +7095,15 @@ static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin) } /* + * Abandon any buffered data we still wanted to send to this + * channel. Receiving a CHANNEL_CLOSE is an indication that + * the server really wants to get on and _destroy_ this + * channel, and it isn't going to send us any further + * WINDOW_ADJUSTs to permit us to send pending stuff. + */ + bufchain_clear(&c->v.v2.outbuffer); + + /* * Send outgoing EOF. */ sshfwd_write_eof(c); @@ -7172,16 +7224,18 @@ static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin) is_int = FALSE; } else { int maybe_int = FALSE, maybe_str = FALSE; -#define CHECK_HYPOTHESIS(offset, result) \ - do { \ - long q = offset; \ - if (q >= 0 && q+4 <= len) { \ - q = q + 4 + GET_32BIT(p+q); \ - if (q >= 0 && q+4 <= len && \ - ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \ - result = TRUE; \ - } \ - } while(0) +#define CHECK_HYPOTHESIS(offset, result) \ + do \ + { \ + int q = toint(offset); \ + if (q >= 0 && q+4 <= len) { \ + q = toint(q + 4 + GET_32BIT(p+q)); \ + if (q >= 0 && q+4 <= len && \ + ((q = toint(q + 4 + GET_32BIT(p+q))) != 0) && \ + q == len) \ + result = TRUE; \ + } \ + } while(0) CHECK_HYPOTHESIS(4+1, maybe_int); CHECK_HYPOTHESIS(4+num+1, maybe_str); #undef CHECK_HYPOTHESIS @@ -7401,6 +7455,7 @@ static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin) else { c->type = CHAN_AGENT; /* identify channel type */ c->u.a.lensofar = 0; + c->u.a.outstanding_requests = 0; } } else { error = "Unsupported channel type requested"; @@ -7498,7 +7553,9 @@ static void ssh2_setup_x11(struct ssh_channel *c, struct Packet *pktin, ssh2_pkt_adduint32(pktout, ssh->x11disp->screennum); ssh2_pkt_send(ssh, pktout); - crWaitUntilV(pktin); + /* Wait to be called back with either a response packet, or NULL + * meaning clean up and free our data */ + crReturnV; if (pktin) { if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) { @@ -7528,7 +7585,9 @@ static void ssh2_setup_agent(struct ssh_channel *c, struct Packet *pktin, ssh2_setup_agent, s); ssh2_pkt_send(ssh, pktout); - crWaitUntilV(pktin); + /* Wait to be called back with either a response packet, or NULL + * meaning clean up and free our data */ + crReturnV; if (pktin) { if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) { @@ -7575,7 +7634,9 @@ static void ssh2_setup_pty(struct ssh_channel *c, struct Packet *pktin, ssh2_pkt_send(ssh, pktout); ssh->state = SSH_STATE_INTERMED; - crWaitUntilV(pktin); + /* Wait to be called back with either a response packet, or NULL + * meaning clean up and free our data */ + crReturnV; if (pktin) { if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) { @@ -7633,7 +7694,9 @@ static void ssh2_setup_env(struct ssh_channel *c, struct Packet *pktin, s->env_left = s->num_env; while (s->env_left > 0) { - crWaitUntilV(pktin); + /* Wait to be called back with either a response packet, + * or NULL meaning clean up and free our data */ + crReturnV; if (!pktin) goto out; if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) s->env_ok++; @@ -7874,13 +7937,53 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int keyi; unsigned char *p; p = s->agent_response + 5; - s->nkeys = GET_32BIT(p); + s->nkeys = toint(GET_32BIT(p)); + + /* + * Vet the Pageant response to ensure that the key + * count and blob lengths make sense. + */ + if (s->nkeys < 0) { + logeventf(ssh, "Pageant response contained a negative" + " key count %d", s->nkeys); + s->nkeys = 0; + goto done_agent_query; + } else { + unsigned char *q = p + 4; + int lenleft = s->agent_responselen - 5 - 4; + + for (keyi = 0; keyi < s->nkeys; keyi++) { + int bloblen, commentlen; + if (lenleft < 4) { + logeventf(ssh, "Pageant response was truncated"); + s->nkeys = 0; + goto done_agent_query; + } + bloblen = toint(GET_32BIT(q)); + if (bloblen < 0 || bloblen > lenleft) { + logeventf(ssh, "Pageant response was truncated"); + s->nkeys = 0; + goto done_agent_query; + } + lenleft -= 4 + bloblen; + q += 4 + bloblen; + commentlen = toint(GET_32BIT(q)); + if (commentlen < 0 || commentlen > lenleft) { + logeventf(ssh, "Pageant response was truncated"); + s->nkeys = 0; + goto done_agent_query; + } + lenleft -= 4 + commentlen; + q += 4 + commentlen; + } + } + p += 4; logeventf(ssh, "Pageant has %d SSH-2 keys", s->nkeys); if (s->publickey_blob) { /* See if configured key is in agent. */ for (keyi = 0; keyi < s->nkeys; keyi++) { - s->pklen = GET_32BIT(p); + s->pklen = toint(GET_32BIT(p)); if (s->pklen == s->publickey_bloblen && !memcmp(p+4, s->publickey_blob, s->publickey_bloblen)) { @@ -7891,7 +7994,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, break; } p += 4 + s->pklen; - p += GET_32BIT(p) + 4; /* comment */ + p += toint(GET_32BIT(p)) + 4; /* comment */ } if (!s->pkblob_in_agent) { logevent("Configured key file not in Pageant"); @@ -7901,6 +8004,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, } else { logevent("Failed to get reply from Pageant"); } + done_agent_query:; } } @@ -8152,13 +8256,13 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, logeventf(ssh, "Trying Pageant key #%d", s->keyi); /* Unpack key from agent response */ - s->pklen = GET_32BIT(s->agentp); + s->pklen = toint(GET_32BIT(s->agentp)); s->agentp += 4; s->pkblob = (char *)s->agentp; s->agentp += s->pklen; - s->alglen = GET_32BIT(s->pkblob); + s->alglen = toint(GET_32BIT(s->pkblob)); s->alg = s->pkblob + 4; - s->commentlen = GET_32BIT(s->agentp); + s->commentlen = toint(GET_32BIT(s->agentp)); s->agentp += 4; s->commentp = (char *)s->agentp; s->agentp += s->commentlen; @@ -8262,7 +8366,9 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, s->ret = vret; sfree(s->agentreq); if (s->ret) { - if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) { + if (s->retlen >= 9 && + s->ret[4] == SSH2_AGENT_SIGN_RESPONSE && + GET_32BIT(s->ret + 5) <= (unsigned)(s->retlen-9)) { logevent("Sending Pageant's response"); ssh2_add_sigblob(ssh, s->pktout, s->pkblob, s->pklen, @@ -9109,66 +9215,30 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, */ if (conf_get_int(ssh->conf, CONF_ssh_no_shell)) { ssh->mainchan = NULL; - } else if (*conf_get_str(ssh->conf, CONF_ssh_nc_host)) { - /* - * Just start a direct-tcpip channel and use it as the main - * channel. - */ + } else { ssh->mainchan = snew(struct ssh_channel); ssh->mainchan->ssh = ssh; ssh2_channel_init(ssh->mainchan); - logeventf(ssh, - "Opening direct-tcpip channel to %s:%d in place of session", - conf_get_str(ssh->conf, CONF_ssh_nc_host), - conf_get_int(ssh->conf, CONF_ssh_nc_port)); - s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); - ssh2_pkt_addstring(s->pktout, "direct-tcpip"); - ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid); - ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */ - ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT); /* our max pkt size */ - ssh2_pkt_addstring(s->pktout, conf_get_str(ssh->conf, CONF_ssh_nc_host)); - ssh2_pkt_adduint32(s->pktout, conf_get_int(ssh->conf, CONF_ssh_nc_port)); - /* - * There's nothing meaningful to put in the originator - * fields, but some servers insist on syntactically correct - * information. - */ - ssh2_pkt_addstring(s->pktout, "0.0.0.0"); - ssh2_pkt_adduint32(s->pktout, 0); - ssh2_pkt_send(ssh, s->pktout); - crWaitUntilV(pktin); - if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) { - bombout(("Server refused to open a direct-tcpip channel")); - crStopV; - /* FIXME: error data comes back in FAILURE packet */ - } - if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) { - bombout(("Server's channel confirmation cited wrong channel")); - crStopV; + if (*conf_get_str(ssh->conf, CONF_ssh_nc_host)) { + /* + * Just start a direct-tcpip channel and use it as the main + * channel. + */ + ssh_send_port_open(ssh->mainchan, + conf_get_str(ssh->conf, CONF_ssh_nc_host), + conf_get_int(ssh->conf, CONF_ssh_nc_port), + "main channel"); + ssh->ncmode = TRUE; + } else { + s->pktout = ssh2_chanopen_init(ssh->mainchan, "session"); + logevent("Opening session as main channel"); + ssh2_pkt_send(ssh, s->pktout); + ssh->ncmode = FALSE; } - ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin); - ssh->mainchan->halfopen = FALSE; - ssh->mainchan->type = CHAN_MAINSESSION; - ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin); - ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin); - add234(ssh->channels, ssh->mainchan); - update_specials_menu(ssh->frontend); - logevent("Opened direct-tcpip channel"); - ssh->ncmode = TRUE; - } else { - ssh->mainchan = snew(struct ssh_channel); - ssh->mainchan->ssh = ssh; - ssh2_channel_init(ssh->mainchan); - s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); - ssh2_pkt_addstring(s->pktout, "session"); - ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid); - ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */ - ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT); /* our max pkt size */ - ssh2_pkt_send(ssh, s->pktout); crWaitUntilV(pktin); if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) { - bombout(("Server refused to open a session")); + bombout(("Server refused to open channel")); crStopV; /* FIXME: error data comes back in FAILURE packet */ } @@ -9183,8 +9253,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin); add234(ssh->channels, ssh->mainchan); update_specials_menu(ssh->frontend); - logevent("Opened channel for session"); - ssh->ncmode = FALSE; + logevent("Opened main channel"); } /* @@ -9498,7 +9567,7 @@ static void ssh2_protocol_setup(Ssh ssh) ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug; } -static void ssh2_timer(void *ctx, long now) +static void ssh2_timer(void *ctx, unsigned long now) { Ssh ssh = (Ssh)ctx; @@ -9506,7 +9575,7 @@ static void ssh2_timer(void *ctx, long now) return; if (!ssh->kex_in_progress && conf_get_int(ssh->conf, CONF_ssh_rekey_time) != 0 && - now - ssh->next_rekey >= 0) { + now == ssh->next_rekey) { do_ssh2_transport(ssh, "timeout", -1, NULL); } } @@ -9701,7 +9770,7 @@ static void ssh_free(void *handle) while (ssh->qhead) { struct queued_handler *qh = ssh->qhead; ssh->qhead = qh->next; - sfree(ssh->qhead); + sfree(qh); } ssh->qhead = ssh->qtail = NULL; @@ -9789,10 +9858,10 @@ static void ssh_reconfig(void *handle, Conf *conf) rekey_time = conf_get_int(conf, CONF_ssh_rekey_time); if (conf_get_int(ssh->conf, CONF_ssh_rekey_time) != rekey_time && rekey_time != 0) { - long new_next = ssh->last_rekey + rekey_time*60*TICKSPERSEC; - long now = GETTICKCOUNT(); + unsigned long new_next = ssh->last_rekey + rekey_time*60*TICKSPERSEC; + unsigned long now = GETTICKCOUNT(); - if (new_next - now < 0) { + if (now - ssh->last_rekey > rekey_time*60*TICKSPERSEC) { rekeying = "timeout shortened"; } else { ssh->next_rekey = schedule_timer(new_next - now, ssh2_timer, ssh); @@ -10145,7 +10214,7 @@ void ssh_send_port_open(void *channel, char *hostname, int port, char *org) Ssh ssh = c->ssh; struct Packet *pktout; - logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port); + logeventf(ssh, "Opening connection to %s:%d for %s", hostname, port, org); if (ssh->version == 1) { send_packet(ssh, SSH1_MSG_PORT_OPEN, @@ -10155,11 +10224,7 @@ void ssh_send_port_open(void *channel, char *hostname, int port, char *org) /* PKT_STR, , */ PKT_END); } else { - pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN); - ssh2_pkt_addstring(pktout, "direct-tcpip"); - ssh2_pkt_adduint32(pktout, c->localid); - ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */ - ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */ + pktout = ssh2_chanopen_init(c, "direct-tcpip"); ssh2_pkt_addstring(pktout, hostname); ssh2_pkt_adduint32(pktout, port); /*