+#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
-#include <winsock.h>
+#include <stdarg.h>
+#include <assert.h>
#include "putty.h"
+#include "tree234.h"
+#include "ssh.h"
#ifndef FALSE
#define FALSE 0
#define TRUE 1
#endif
-#include "ssh.h"
+#define logevent(s) { logevent(s); \
+ if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
+ fprintf(stderr, "%s\n", s); }
+
+#define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \
+ (s ? sk_close(s), s = NULL : (void)0), \
+ connection_fatal msg )
+
+#define SSH1_MSG_DISCONNECT 1 /* 0x1 */
+#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
+#define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
+#define SSH1_CMSG_USER 4 /* 0x4 */
+#define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
+#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
+#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
+#define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
+#define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
+#define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
+#define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
+#define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
+#define SSH1_SMSG_SUCCESS 14 /* 0xe */
+#define SSH1_SMSG_FAILURE 15 /* 0xf */
+#define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
+#define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
+#define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
+#define SSH1_CMSG_EOF 19 /* 0x13 */
+#define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
+#define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
+#define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
+#define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
+#define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
+#define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
+#define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
+#define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
+#define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
+#define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
+#define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
+#define SSH1_MSG_IGNORE 32 /* 0x20 */
+#define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
+#define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
+#define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
+#define SSH1_MSG_DEBUG 36 /* 0x24 */
+#define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
+#define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
+#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
+#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
+#define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
+#define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
+#define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
+
+#define SSH1_AUTH_TIS 5 /* 0x5 */
+#define SSH1_AUTH_CCARD 16 /* 0x10 */
+
+#define SSH_AGENTC_REQUEST_RSA_IDENTITIES 1 /* 0x1 */
+#define SSH_AGENT_RSA_IDENTITIES_ANSWER 2 /* 0x2 */
+#define SSH_AGENTC_RSA_CHALLENGE 3 /* 0x3 */
+#define SSH_AGENT_RSA_RESPONSE 4 /* 0x4 */
+#define SSH_AGENT_FAILURE 5 /* 0x5 */
+#define SSH_AGENT_SUCCESS 6 /* 0x6 */
+#define SSH_AGENTC_ADD_RSA_IDENTITY 7 /* 0x7 */
+#define SSH_AGENTC_REMOVE_RSA_IDENTITY 8 /* 0x8 */
+
+#define SSH2_MSG_DISCONNECT 1 /* 0x1 */
+#define SSH2_MSG_IGNORE 2 /* 0x2 */
+#define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
+#define SSH2_MSG_DEBUG 4 /* 0x4 */
+#define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
+#define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
+#define SSH2_MSG_KEXINIT 20 /* 0x14 */
+#define SSH2_MSG_NEWKEYS 21 /* 0x15 */
+#define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
+#define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
+#define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
+#define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
+#define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
+#define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
+#define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
+#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
+#define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
+#define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
+#define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
+#define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
+#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
+#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
+#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
+#define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
+#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
+#define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
+#define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
+#define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
+#define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
+#define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
+
+#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
+#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
+#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
+#define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
+#define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
+#define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
+#define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
+#define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
+#define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
+#define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
+#define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
+
+#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
+#define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
+#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
+#define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
+
+#define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
+
+#define GET_32BIT(cp) \
+ (((unsigned long)(unsigned char)(cp)[0] << 24) | \
+ ((unsigned long)(unsigned char)(cp)[1] << 16) | \
+ ((unsigned long)(unsigned char)(cp)[2] << 8) | \
+ ((unsigned long)(unsigned char)(cp)[3]))
+
+#define PUT_32BIT(cp, value) { \
+ (cp)[0] = (unsigned char)((value) >> 24); \
+ (cp)[1] = (unsigned char)((value) >> 16); \
+ (cp)[2] = (unsigned char)((value) >> 8); \
+ (cp)[3] = (unsigned char)(value); }
+
+enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
/* Coroutine mechanics for the sillier bits of the code */
#define crBegin1 static int crLine = 0;
} while (0)
#define crStop(z) do{ crLine = 0; return (z); }while(0)
#define crStopV do{ crLine = 0; return; }while(0)
+#define crWaitUntil(c) do { crReturn(0); } while (!(c))
+#define crWaitUntilV(c) do { crReturnV; } while (!(c))
-#ifndef FALSE
-#define FALSE 0
-#endif
-#ifndef TRUE
-#define TRUE 1
-#endif
+extern const struct ssh_cipher ssh_3des;
+extern const struct ssh_cipher ssh_3des_ssh2;
+extern const struct ssh_cipher ssh_des;
+extern const struct ssh_cipher ssh_blowfish_ssh1;
+extern const struct ssh_cipher ssh_blowfish_ssh2;
-static SOCKET s = INVALID_SOCKET;
+extern char *x11_init (Socket *, char *, void *);
+extern void x11_close (Socket);
+extern void x11_send (Socket , char *, int);
+extern void x11_invent_auth(char *, int, char *, int);
-static unsigned char session_key[32];
-static struct ssh_cipher *cipher = NULL;
-
-static char *savedhost;
+/*
+ * Ciphers for SSH2. We miss out single-DES because it isn't
+ * supported; also 3DES and Blowfish are both done differently from
+ * SSH1. (3DES uses outer chaining; Blowfish has the opposite
+ * endianness and different-sized keys.)
+ */
+const static struct ssh_cipher *ciphers[] = { &ssh_blowfish_ssh2, &ssh_3des_ssh2 };
-static enum {
- SSH_STATE_BEFORE_SIZE,
- SSH_STATE_INTERMED,
- SSH_STATE_SESSION
-} ssh_state = SSH_STATE_BEFORE_SIZE;
+extern const struct ssh_kex ssh_diffiehellman;
+const static struct ssh_kex *kex_algs[] = { &ssh_diffiehellman };
-static int size_needed = FALSE;
+extern const struct ssh_signkey ssh_dss;
+const static struct ssh_signkey *hostkey_algs[] = { &ssh_dss };
-static void s_write (char *buf, int len) {
- while (len > 0) {
- int i = send (s, buf, len, 0);
- if (i > 0)
- len -= i, buf += i;
- }
-}
+extern const struct ssh_mac ssh_md5, ssh_sha1, ssh_sha1_buggy;
-static int s_read (char *buf, int len) {
- int ret = 0;
- while (len > 0) {
- int i = recv (s, buf, len, 0);
- if (i > 0)
- len -= i, buf += i, ret += i;
- else
- return i;
- }
- return ret;
+static void nullmac_key(unsigned char *key) { }
+static void nullmac_generate(unsigned char *blk, int len, unsigned long seq) { }
+static int nullmac_verify(unsigned char *blk, int len, unsigned long seq) { return 1; }
+const static struct ssh_mac ssh_mac_none = {
+ nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
+};
+const static struct ssh_mac *macs[] = {
+ &ssh_sha1, &ssh_md5, &ssh_mac_none };
+const static struct ssh_mac *buggymacs[] = {
+ &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none };
+
+static void ssh_comp_none_init(void) { }
+static int ssh_comp_none_block(unsigned char *block, int len,
+ unsigned char **outblock, int *outlen) {
+ return 0;
}
+const static struct ssh_compress ssh_comp_none = {
+ "none",
+ ssh_comp_none_init, ssh_comp_none_block,
+ ssh_comp_none_init, ssh_comp_none_block
+};
+extern const struct ssh_compress ssh_zlib;
+const static struct ssh_compress *compressions[] = {
+ &ssh_zlib, &ssh_comp_none };
+
+enum { /* channel types */
+ CHAN_MAINSESSION,
+ CHAN_X11,
+ CHAN_AGENT,
+};
-static void c_write (char *buf, int len) {
- while (len--) {
- int new_head = (inbuf_head + 1) & INBUF_MASK;
- int c = (unsigned char) *buf;
- if (new_head != inbuf_reap) {
- inbuf[inbuf_head] = *buf++;
- inbuf_head = new_head;
- }
- }
-}
+/*
+ * 2-3-4 tree storing channels.
+ */
+struct ssh_channel {
+ unsigned remoteid, localid;
+ int type;
+ int closes;
+ struct ssh2_data_channel {
+ unsigned char *outbuffer;
+ unsigned outbuflen, outbufsize;
+ unsigned remwindow, remmaxpkt;
+ } v2;
+ union {
+ struct ssh_agent_channel {
+ unsigned char *message;
+ unsigned char msglen[4];
+ int lensofar, totallen;
+ } a;
+ struct ssh_x11_channel {
+ Socket s;
+ } x11;
+ } u;
+};
struct Packet {
long length;
int type;
- unsigned long crc;
unsigned char *data;
unsigned char *body;
+ long savedpos;
long maxlen;
};
-static struct Packet pktin = { 0, 0, 0, NULL, 0 };
-static struct Packet pktout = { 0, 0, 0, NULL, 0 };
+static SHA_State exhash, exhashbase;
+
+static Socket s = NULL;
+
+static unsigned char session_key[32];
+static int ssh1_compressing;
+static int ssh_agentfwd_enabled;
+static int ssh_X11_fwd_enabled;
+static const struct ssh_cipher *cipher = NULL;
+static const struct ssh_cipher *cscipher = NULL;
+static const struct ssh_cipher *sccipher = NULL;
+static const struct ssh_mac *csmac = NULL;
+static const struct ssh_mac *scmac = NULL;
+static const struct ssh_compress *cscomp = NULL;
+static const struct ssh_compress *sccomp = NULL;
+static const struct ssh_kex *kex = NULL;
+static const struct ssh_signkey *hostkey = NULL;
+int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
+
+static char *savedhost;
+static int savedport;
+static int ssh_send_ok;
+static int ssh_echoing, ssh_editing;
+
+static tree234 *ssh_channels; /* indexed by local id */
+static struct ssh_channel *mainchan; /* primary session channel */
-static void ssh_protocol(unsigned char *in, int inlen, int ispkt);
+static enum {
+ SSH_STATE_PREPACKET,
+ SSH_STATE_BEFORE_SIZE,
+ SSH_STATE_INTERMED,
+ SSH_STATE_SESSION,
+ SSH_STATE_CLOSED
+} ssh_state = SSH_STATE_PREPACKET;
+
+static int size_needed = FALSE, eof_needed = FALSE;
+
+static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
+static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
+
+static int ssh_version;
+static void (*ssh_protocol)(unsigned char *in, int inlen, int ispkt);
+static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
+static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
static void ssh_size(void);
+static void ssh_special (Telnet_Special);
+static void ssh2_try_send(struct ssh_channel *c);
+static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
+
+static int (*s_rdpkt)(unsigned char **data, int *datalen);
-static void ssh_gotdata(unsigned char *data, int datalen) {
- static long len, biglen, to_read;
- static unsigned char c, *p;
- static int i, pad;
- static char padding[8];
- static unsigned char word[4];
+static struct rdpkt1_state_tag {
+ long len, pad, biglen, to_read;
+ unsigned long realcrc, gotcrc;
+ unsigned char *p;
+ int i;
+ int chunk;
+} rdpkt1_state;
+
+static struct rdpkt2_state_tag {
+ long len, pad, payload, packetlen, maclen;
+ int i;
+ int cipherblk;
+ unsigned long incoming_sequence;
+} rdpkt2_state;
+
+static int ssh_channelcmp(void *av, void *bv) {
+ struct ssh_channel *a = (struct ssh_channel *)av;
+ struct ssh_channel *b = (struct ssh_channel *)bv;
+ if (a->localid < b->localid) return -1;
+ if (a->localid > b->localid) return +1;
+ return 0;
+}
+static int ssh_channelfind(void *av, void *bv) {
+ unsigned *a = (unsigned *)av;
+ struct ssh_channel *b = (struct ssh_channel *)bv;
+ if (*a < b->localid) return -1;
+ if (*a > b->localid) return +1;
+ return 0;
+}
+
+static void c_write (char *buf, int len) {
+ if ((flags & FLAG_STDERR)) {
+ int i;
+ for (i = 0; i < len; i++)
+ if (buf[i] != '\r')
+ fputc(buf[i], stderr);
+ return;
+ }
+ from_backend(1, buf, len);
+}
+
+/*
+ * Collect incoming data in the incoming packet buffer.
+ * Decipher and verify the packet when it is completely read.
+ * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
+ * Update the *data and *datalen variables.
+ * Return the additional nr of bytes needed, or 0 when
+ * a complete packet is available.
+ */
+static int ssh1_rdpkt(unsigned char **data, int *datalen)
+{
+ struct rdpkt1_state_tag *st = &rdpkt1_state;
crBegin;
- while (1) {
- for (i = len = 0; i < 4; i++) {
- while (datalen == 0)
- crReturnV;
- len = (len << 8) + *data;
- data++, datalen--;
- }
- pad = 8 - (len%8);
+next_packet:
- biglen = len + pad;
+ pktin.type = 0;
+ pktin.length = 0;
- len -= 5; /* type and CRC */
+ for (st->i = st->len = 0; st->i < 4; st->i++) {
+ while ((*datalen) == 0)
+ crReturn(4-st->i);
+ st->len = (st->len << 8) + **data;
+ (*data)++, (*datalen)--;
+ }
+
+#ifdef FWHACK
+ if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */
+ st->len = 0x300; /* big enough to carry to end */
+ }
+#endif
+
+ st->pad = 8 - (st->len % 8);
+ st->biglen = st->len + st->pad;
+ pktin.length = st->len - 5;
+
+ if (pktin.maxlen < st->biglen) {
+ pktin.maxlen = st->biglen;
+ pktin.data = (pktin.data == NULL ? smalloc(st->biglen+APIEXTRA) :
+ srealloc(pktin.data, st->biglen+APIEXTRA));
+ if (!pktin.data)
+ fatalbox("Out of memory");
+ }
+
+ st->to_read = st->biglen;
+ st->p = pktin.data;
+ while (st->to_read > 0) {
+ st->chunk = st->to_read;
+ while ((*datalen) == 0)
+ crReturn(st->to_read);
+ if (st->chunk > (*datalen))
+ st->chunk = (*datalen);
+ memcpy(st->p, *data, st->chunk);
+ *data += st->chunk;
+ *datalen -= st->chunk;
+ st->p += st->chunk;
+ st->to_read -= st->chunk;
+ }
+
+ if (cipher)
+ cipher->decrypt(pktin.data, st->biglen);
+#if 0
+ debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
+ for (st->i = 0; st->i < st->biglen; st->i++)
+ debug((" %02x", (unsigned char)pktin.data[st->i]));
+ debug(("\r\n"));
+#endif
+
+ st->realcrc = crc32(pktin.data, st->biglen-4);
+ st->gotcrc = GET_32BIT(pktin.data+st->biglen-4);
+ if (st->gotcrc != st->realcrc) {
+ bombout(("Incorrect CRC received on packet"));
+ crReturn(0);
+ }
+
+ pktin.body = pktin.data + st->pad + 1;
+
+ if (ssh1_compressing) {
+ unsigned char *decompblk;
+ int decomplen;
+#if 0
+ int i;
+ debug(("Packet payload pre-decompression:\n"));
+ for (i = -1; i < pktin.length; i++)
+ debug((" %02x", (unsigned char)pktin.body[i]));
+ debug(("\r\n"));
+#endif
+ zlib_decompress_block(pktin.body-1, pktin.length+1,
+ &decompblk, &decomplen);
- pktin.length = len;
- if (pktin.maxlen < biglen) {
- pktin.maxlen = biglen;
- pktin.data = (pktin.data == NULL ? malloc(biglen) :
- realloc(pktin.data, biglen));
+ if (pktin.maxlen < st->pad + decomplen) {
+ pktin.maxlen = st->pad + decomplen;
+ pktin.data = srealloc(pktin.data, pktin.maxlen+APIEXTRA);
+ pktin.body = pktin.data + st->pad + 1;
if (!pktin.data)
fatalbox("Out of memory");
}
- p = pktin.data, to_read = biglen;
- while (to_read > 0) {
- static int chunk;
- chunk = to_read;
- while (datalen == 0)
- crReturnV;
- if (chunk > datalen)
- chunk = datalen;
- memcpy(p, data, chunk);
- data += chunk;
- datalen -= chunk;
- p += chunk;
- to_read -= chunk;
- }
+ memcpy(pktin.body-1, decompblk, decomplen);
+ sfree(decompblk);
+ pktin.length = decomplen-1;
+#if 0
+ debug(("Packet payload post-decompression:\n"));
+ for (i = -1; i < pktin.length; i++)
+ debug((" %02x", (unsigned char)pktin.body[i]));
+ debug(("\r\n"));
+#endif
+ }
- if (cipher)
- cipher->decrypt(pktin.data, biglen);
+ if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
+ pktin.type == SSH1_SMSG_STDERR_DATA ||
+ pktin.type == SSH1_MSG_DEBUG ||
+ pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
+ pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
+ long strlen = GET_32BIT(pktin.body);
+ if (strlen + 4 != pktin.length) {
+ bombout(("Received data packet with bogus string length"));
+ crReturn(0);
+ }
+ }
- pktin.type = pktin.data[pad];
- pktin.body = pktin.data+pad+1;
+ pktin.type = pktin.body[-1];
+
+ if (pktin.type == SSH1_MSG_DEBUG) {
+ /* log debug message */
+ char buf[80];
+ int strlen = GET_32BIT(pktin.body);
+ strcpy(buf, "Remote: ");
+ if (strlen > 70) strlen = 70;
+ memcpy(buf+8, pktin.body+4, strlen);
+ buf[8+strlen] = '\0';
+ logevent(buf);
+ goto next_packet;
+ } else if (pktin.type == SSH1_MSG_IGNORE) {
+ /* do nothing */
+ goto next_packet;
+ }
- if (pktin.type == 36) { /* SSH_MSG_DEBUG */
- /* FIXME: log it */
- } else
- ssh_protocol(NULL, 0, 1);
+ crFinish(0);
+}
+
+static int ssh2_rdpkt(unsigned char **data, int *datalen)
+{
+ struct rdpkt2_state_tag *st = &rdpkt2_state;
+
+ crBegin;
+
+next_packet:
+ pktin.type = 0;
+ pktin.length = 0;
+ if (sccipher)
+ st->cipherblk = sccipher->blksize;
+ else
+ st->cipherblk = 8;
+ if (st->cipherblk < 8)
+ st->cipherblk = 8;
+
+ if (pktin.maxlen < st->cipherblk) {
+ pktin.maxlen = st->cipherblk;
+ pktin.data = (pktin.data == NULL ? smalloc(st->cipherblk+APIEXTRA) :
+ srealloc(pktin.data, st->cipherblk+APIEXTRA));
+ if (!pktin.data)
+ fatalbox("Out of memory");
}
- crFinishV;
+
+ /*
+ * Acquire and decrypt the first block of the packet. This will
+ * contain the length and padding details.
+ */
+ for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
+ while ((*datalen) == 0)
+ crReturn(st->cipherblk-st->i);
+ pktin.data[st->i] = *(*data)++;
+ (*datalen)--;
+ }
+#ifdef FWHACK
+ if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
+ /* FIXME */
+ }
+#endif
+ if (sccipher)
+ sccipher->decrypt(pktin.data, st->cipherblk);
+
+ /*
+ * Now get the length and padding figures.
+ */
+ st->len = GET_32BIT(pktin.data);
+ st->pad = pktin.data[4];
+
+ /*
+ * This enables us to deduce the payload length.
+ */
+ st->payload = st->len - st->pad - 1;
+
+ pktin.length = st->payload + 5;
+
+ /*
+ * So now we can work out the total packet length.
+ */
+ st->packetlen = st->len + 4;
+ st->maclen = scmac ? scmac->len : 0;
+
+ /*
+ * Adjust memory allocation if packet is too big.
+ */
+ if (pktin.maxlen < st->packetlen+st->maclen) {
+ pktin.maxlen = st->packetlen+st->maclen;
+ pktin.data = (pktin.data == NULL ? smalloc(pktin.maxlen+APIEXTRA) :
+ srealloc(pktin.data, pktin.maxlen+APIEXTRA));
+ if (!pktin.data)
+ fatalbox("Out of memory");
+ }
+
+ /*
+ * Read and decrypt the remainder of the packet.
+ */
+ for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) {
+ while ((*datalen) == 0)
+ crReturn(st->packetlen + st->maclen - st->i);
+ pktin.data[st->i] = *(*data)++;
+ (*datalen)--;
+ }
+ /* Decrypt everything _except_ the MAC. */
+ if (sccipher)
+ sccipher->decrypt(pktin.data + st->cipherblk,
+ st->packetlen - st->cipherblk);
+
+#if 0
+ debug(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
+ for (st->i = 0; st->i < st->packetlen; st->i++)
+ debug((" %02x", (unsigned char)pktin.data[st->i]));
+ debug(("\r\n"));
+#endif
+
+ /*
+ * Check the MAC.
+ */
+ if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) {
+ bombout(("Incorrect MAC received on packet"));
+ crReturn(0);
+ }
+ st->incoming_sequence++; /* whether or not we MACed */
+
+ /*
+ * Decompress packet payload.
+ */
+ {
+ unsigned char *newpayload;
+ int newlen;
+ if (sccomp && sccomp->decompress(pktin.data+5, pktin.length-5,
+ &newpayload, &newlen)) {
+ if (pktin.maxlen < newlen+5) {
+ pktin.maxlen = newlen+5;
+ pktin.data = (pktin.data == NULL ? smalloc(pktin.maxlen+APIEXTRA) :
+ srealloc(pktin.data, pktin.maxlen+APIEXTRA));
+ if (!pktin.data)
+ fatalbox("Out of memory");
+ }
+ pktin.length = 5 + newlen;
+ memcpy(pktin.data+5, newpayload, newlen);
+#if 0
+ debug(("Post-decompression payload:\r\n"));
+ for (st->i = 0; st->i < newlen; st->i++)
+ debug((" %02x", (unsigned char)pktin.data[5+st->i]));
+ debug(("\r\n"));
+#endif
+
+ sfree(newpayload);
+ }
+ }
+
+ pktin.savedpos = 6;
+ pktin.type = pktin.data[5];
+
+ if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
+ goto next_packet; /* FIXME: print DEBUG message */
+
+ crFinish(0);
}
-static void s_wrpkt_start(int type, int len) {
+static void ssh1_pktout_size(int len) {
int pad, biglen;
len += 5; /* type and CRC */
pktout.length = len-5;
if (pktout.maxlen < biglen) {
pktout.maxlen = biglen;
- pktout.data = (pktout.data == NULL ? malloc(biglen) :
- realloc(pktout.data, biglen));
+#ifdef MSCRYPTOAPI
+ /* Allocate enough buffer space for extra block
+ * for MS CryptEncrypt() */
+ pktout.data = (pktout.data == NULL ? smalloc(biglen+12) :
+ srealloc(pktout.data, biglen+12));
+#else
+ pktout.data = (pktout.data == NULL ? smalloc(biglen+4) :
+ srealloc(pktout.data, biglen+4));
+#endif
if (!pktout.data)
fatalbox("Out of memory");
}
+ pktout.body = pktout.data+4+pad+1;
+}
+static void s_wrpkt_start(int type, int len) {
+ ssh1_pktout_size(len);
pktout.type = type;
- pktout.body = pktout.data+4+pad+1;
}
static void s_wrpkt(void) {
int pad, len, biglen, i;
unsigned long crc;
+ pktout.body[-1] = pktout.type;
+
+ if (ssh1_compressing) {
+ unsigned char *compblk;
+ int complen;
+#if 0
+ debug(("Packet payload pre-compression:\n"));
+ for (i = -1; i < pktout.length; i++)
+ debug((" %02x", (unsigned char)pktout.body[i]));
+ debug(("\r\n"));
+#endif
+ zlib_compress_block(pktout.body-1, pktout.length+1,
+ &compblk, &complen);
+ ssh1_pktout_size(complen-1);
+ memcpy(pktout.body-1, compblk, complen);
+ sfree(compblk);
+#if 0
+ debug(("Packet payload post-compression:\n"));
+ for (i = -1; i < pktout.length; i++)
+ debug((" %02x", (unsigned char)pktout.body[i]));
+ debug(("\r\n"));
+#endif
+ }
+
len = pktout.length + 5; /* type and CRC */
pad = 8 - (len%8);
biglen = len + pad;
- pktout.body[-1] = pktout.type;
for (i=0; i<pad; i++)
pktout.data[i+4] = random_byte();
crc = crc32(pktout.data+4, biglen-4);
+ PUT_32BIT(pktout.data+biglen, crc);
+ PUT_32BIT(pktout.data, len);
+
+#if 0
+ debug(("Sending packet len=%d\r\n", biglen+4));
+ for (i = 0; i < biglen+4; i++)
+ debug((" %02x", (unsigned char)pktout.data[i]));
+ debug(("\r\n"));
+#endif
+ if (cipher)
+ cipher->encrypt(pktout.data+4, biglen);
+
+ sk_write(s, pktout.data, biglen+4);
+}
+
+/*
+ * Construct a packet with the specified contents and
+ * send it to the server.
+ */
+static void send_packet(int pkttype, ...)
+{
+ va_list args;
+ unsigned char *p, *argp, argchar;
+ unsigned long argint;
+ int pktlen, argtype, arglen;
+ Bignum bn;
+
+ pktlen = 0;
+ va_start(args, pkttype);
+ while ((argtype = va_arg(args, int)) != PKT_END) {
+ switch (argtype) {
+ case PKT_INT:
+ (void) va_arg(args, int);
+ pktlen += 4;
+ break;
+ case PKT_CHAR:
+ (void) va_arg(args, char);
+ pktlen++;
+ break;
+ case PKT_DATA:
+ (void) va_arg(args, unsigned char *);
+ arglen = va_arg(args, int);
+ pktlen += arglen;
+ break;
+ case PKT_STR:
+ argp = va_arg(args, unsigned char *);
+ arglen = strlen(argp);
+ pktlen += 4 + arglen;
+ break;
+ case PKT_BIGNUM:
+ bn = va_arg(args, Bignum);
+ pktlen += ssh1_bignum_length(bn);
+ break;
+ default:
+ assert(0);
+ }
+ }
+ va_end(args);
+
+ s_wrpkt_start(pkttype, pktlen);
+ p = pktout.body;
+
+ va_start(args, pkttype);
+ while ((argtype = va_arg(args, int)) != PKT_END) {
+ switch (argtype) {
+ case PKT_INT:
+ argint = va_arg(args, int);
+ PUT_32BIT(p, argint);
+ p += 4;
+ break;
+ case PKT_CHAR:
+ argchar = va_arg(args, unsigned char);
+ *p = argchar;
+ p++;
+ break;
+ case PKT_DATA:
+ argp = va_arg(args, unsigned char *);
+ arglen = va_arg(args, int);
+ memcpy(p, argp, arglen);
+ p += arglen;
+ break;
+ case PKT_STR:
+ argp = va_arg(args, unsigned char *);
+ arglen = strlen(argp);
+ PUT_32BIT(p, arglen);
+ memcpy(p + 4, argp, arglen);
+ p += 4 + arglen;
+ break;
+ case PKT_BIGNUM:
+ bn = va_arg(args, Bignum);
+ p += ssh1_write_bignum(p, bn);
+ break;
+ }
+ }
+ va_end(args);
+
+ s_wrpkt();
+}
+
+static int ssh_versioncmp(char *a, char *b) {
+ char *ae, *be;
+ unsigned long av, bv;
+
+ av = strtoul(a, &ae, 10);
+ bv = strtoul(b, &be, 10);
+ if (av != bv) return (av < bv ? -1 : +1);
+ if (*ae == '.') ae++;
+ if (*be == '.') be++;
+ av = strtoul(ae, &ae, 10);
+ bv = strtoul(be, &be, 10);
+ if (av != bv) return (av < bv ? -1 : +1);
+ return 0;
+}
+
+
+/*
+ * Utility routine for putting an SSH-protocol `string' into a SHA
+ * state.
+ */
+#include <stdio.h>
+static void sha_string(SHA_State *s, void *str, int len) {
+ unsigned char lenblk[4];
+ PUT_32BIT(lenblk, len);
+ SHA_Bytes(s, lenblk, 4);
+ SHA_Bytes(s, str, len);
+}
+
+/*
+ * SSH2 packet construction functions.
+ */
+static void ssh2_pkt_ensure(int length) {
+ if (pktout.maxlen < length) {
+ pktout.maxlen = length + 256;
+ pktout.data = (pktout.data == NULL ? smalloc(pktout.maxlen+APIEXTRA) :
+ srealloc(pktout.data, pktout.maxlen+APIEXTRA));
+ if (!pktout.data)
+ fatalbox("Out of memory");
+ }
+}
+static void ssh2_pkt_adddata(void *data, int len) {
+ pktout.length += len;
+ ssh2_pkt_ensure(pktout.length);
+ memcpy(pktout.data+pktout.length-len, data, len);
+}
+static void ssh2_pkt_addbyte(unsigned char byte) {
+ ssh2_pkt_adddata(&byte, 1);
+}
+static void ssh2_pkt_init(int pkt_type) {
+ pktout.length = 5;
+ ssh2_pkt_addbyte((unsigned char)pkt_type);
+}
+static void ssh2_pkt_addbool(unsigned char value) {
+ ssh2_pkt_adddata(&value, 1);
+}
+static void ssh2_pkt_adduint32(unsigned long value) {
+ unsigned char x[4];
+ PUT_32BIT(x, value);
+ ssh2_pkt_adddata(x, 4);
+}
+static void ssh2_pkt_addstring_start(void) {
+ ssh2_pkt_adduint32(0);
+ pktout.savedpos = pktout.length;
+}
+static void ssh2_pkt_addstring_str(char *data) {
+ ssh2_pkt_adddata(data, strlen(data));
+ PUT_32BIT(pktout.data + pktout.savedpos - 4,
+ pktout.length - pktout.savedpos);
+}
+static void ssh2_pkt_addstring_data(char *data, int len) {
+ ssh2_pkt_adddata(data, len);
+ PUT_32BIT(pktout.data + pktout.savedpos - 4,
+ pktout.length - pktout.savedpos);
+}
+static void ssh2_pkt_addstring(char *data) {
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_addstring_str(data);
+}
+static char *ssh2_mpint_fmt(Bignum b, int *len) {
+ unsigned char *p;
+ int i, n = b[0];
+ p = smalloc(n * 2 + 1);
+ if (!p)
+ fatalbox("out of memory");
+ p[0] = 0;
+ for (i = 0; i < n; i++) {
+ p[i*2+1] = (b[n-i] >> 8) & 0xFF;
+ p[i*2+2] = (b[n-i] ) & 0xFF;
+ }
+ i = 0;
+ while (p[i] == 0 && (p[i+1] & 0x80) == 0)
+ i++;
+ memmove(p, p+i, n*2+1-i);
+ *len = n*2+1-i;
+ return p;
+}
+static void ssh2_pkt_addmp(Bignum b) {
+ unsigned char *p;
+ int len;
+ p = ssh2_mpint_fmt(b, &len);
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_addstring_data(p, len);
+ sfree(p);
+}
+static void ssh2_pkt_send(void) {
+ int cipherblk, maclen, padding, i;
+ static unsigned long outgoing_sequence = 0;
+
+ /*
+ * Compress packet payload.
+ */
+#if 0
+ debug(("Pre-compression payload:\r\n"));
+ for (i = 5; i < pktout.length; i++)
+ debug((" %02x", (unsigned char)pktout.data[i]));
+ debug(("\r\n"));
+#endif
+ {
+ unsigned char *newpayload;
+ int newlen;
+ if (cscomp && cscomp->compress(pktout.data+5, pktout.length-5,
+ &newpayload, &newlen)) {
+ pktout.length = 5;
+ ssh2_pkt_adddata(newpayload, newlen);
+ sfree(newpayload);
+ }
+ }
+
+ /*
+ * Add padding. At least four bytes, and must also bring total
+ * length (minus MAC) up to a multiple of the block size.
+ */
+ cipherblk = cipher ? cipher->blksize : 8; /* block size */
+ cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
+ padding = 4;
+ padding += (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
+ maclen = csmac ? csmac->len : 0;
+ ssh2_pkt_ensure(pktout.length + padding + maclen);
+ pktout.data[4] = padding;
+ for (i = 0; i < padding; i++)
+ pktout.data[pktout.length + i] = random_byte();
+ PUT_32BIT(pktout.data, pktout.length + padding - 4);
+ if (csmac)
+ csmac->generate(pktout.data, pktout.length + padding,
+ outgoing_sequence);
+ outgoing_sequence++; /* whether or not we MACed */
+
+#if 0
+ debug(("Sending packet len=%d\r\n", pktout.length+padding));
+ for (i = 0; i < pktout.length+padding; i++)
+ debug((" %02x", (unsigned char)pktout.data[i]));
+ debug(("\r\n"));
+#endif
+
+ if (cscipher)
+ cscipher->encrypt(pktout.data, pktout.length + padding);
+
+ sk_write(s, pktout.data, pktout.length + padding + maclen);
+}
+
+#if 0
+void bndebug(char *string, Bignum b) {
+ unsigned char *p;
+ int i, len;
+ p = ssh2_mpint_fmt(b, &len);
+ debug(("%s", string));
+ for (i = 0; i < len; i++)
+ debug((" %02x", p[i]));
+ debug(("\r\n"));
+ sfree(p);
+}
+#endif
+
+static void sha_mpint(SHA_State *s, Bignum b) {
+ unsigned char *p;
+ int len;
+ p = ssh2_mpint_fmt(b, &len);
+ sha_string(s, p, len);
+ sfree(p);
+}
+
+/*
+ * SSH2 packet decode functions.
+ */
+static unsigned long ssh2_pkt_getuint32(void) {
+ unsigned long value;
+ if (pktin.length - pktin.savedpos < 4)
+ return 0; /* arrgh, no way to decline (FIXME?) */
+ value = GET_32BIT(pktin.data+pktin.savedpos);
+ pktin.savedpos += 4;
+ return value;
+}
+static void ssh2_pkt_getstring(char **p, int *length) {
+ *p = NULL;
+ if (pktin.length - pktin.savedpos < 4)
+ return;
+ *length = GET_32BIT(pktin.data+pktin.savedpos);
+ pktin.savedpos += 4;
+ if (pktin.length - pktin.savedpos < *length)
+ return;
+ *p = pktin.data+pktin.savedpos;
+ pktin.savedpos += *length;
+}
+static Bignum ssh2_pkt_getmp(void) {
+ char *p;
+ int i, j, length;
+ Bignum b;
+
+ ssh2_pkt_getstring(&p, &length);
+ if (!p)
+ return NULL;
+ if (p[0] & 0x80) {
+ bombout(("internal error: Can't handle negative mpints"));
+ return NULL;
+ }
+ b = newbn((length+1)/2);
+ for (i = 0; i < length; i++) {
+ j = length - 1 - i;
+ if (j & 1)
+ b[j/2+1] |= ((unsigned char)p[i]) << 8;
+ else
+ b[j/2+1] |= ((unsigned char)p[i]);
+ }
+ while (b[0] > 1 && b[b[0]] == 0) b[0]--;
+ return b;
+}
+
+static int do_ssh_init(unsigned char c) {
+ static char *vsp;
+ static char version[10];
+ static char vstring[80];
+ static char vlog[sizeof(vstring)+20];
+ static int i;
+
+ crBegin;
+
+ /* Search for the string "SSH-" in the input. */
+ i = 0;
+ while (1) {
+ static const int transS[] = { 1, 2, 2, 1 };
+ static const int transH[] = { 0, 0, 3, 0 };
+ static const int transminus[] = { 0, 0, 0, -1 };
+ if (c == 'S') i = transS[i];
+ else if (c == 'H') i = transH[i];
+ else if (c == '-') i = transminus[i];
+ else i = 0;
+ if (i < 0)
+ break;
+ crReturn(1); /* get another character */
+ }
+
+ strcpy(vstring, "SSH-");
+ vsp = vstring+4;
+ i = 0;
+ while (1) {
+ crReturn(1); /* get another char */
+ if (vsp < vstring+sizeof(vstring)-1)
+ *vsp++ = c;
+ if (i >= 0) {
+ if (c == '-') {
+ version[i] = '\0';
+ i = -1;
+ } else if (i < sizeof(version)-1)
+ version[i++] = c;
+ }
+ else if (c == '\n')
+ break;
+ }
+
+ ssh_agentfwd_enabled = FALSE;
+ rdpkt2_state.incoming_sequence = 0;
+
+ *vsp = 0;
+ sprintf(vlog, "Server version: %s", vstring);
+ vlog[strcspn(vlog, "\r\n")] = '\0';
+ logevent(vlog);
+
+ /*
+ * Server version "1.99" means we can choose whether we use v1
+ * or v2 protocol. Choice is based on cfg.sshprot.
+ */
+ if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
+ /*
+ * This is a v2 server. Begin v2 protocol.
+ */
+ char *verstring = "SSH-2.0-PuTTY";
+ SHA_Init(&exhashbase);
+ /*
+ * Hash our version string and their version string.
+ */
+ sha_string(&exhashbase, verstring, strlen(verstring));
+ sha_string(&exhashbase, vstring, strcspn(vstring, "\r\n"));
+ sprintf(vstring, "%s\n", verstring);
+ sprintf(vlog, "We claim version: %s", verstring);
+ logevent(vlog);
+ logevent("Using SSH protocol version 2");
+ sk_write(s, vstring, strlen(vstring));
+ ssh_protocol = ssh2_protocol;
+ ssh_version = 2;
+ s_rdpkt = ssh2_rdpkt;
+ } else {
+ /*
+ * This is a v1 server. Begin v1 protocol.
+ */
+ sprintf(vstring, "SSH-%s-PuTTY\n",
+ (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
+ sprintf(vlog, "We claim version: %s", vstring);
+ vlog[strcspn(vlog, "\r\n")] = '\0';
+ logevent(vlog);
+ logevent("Using SSH protocol version 1");
+ sk_write(s, vstring, strlen(vstring));
+ ssh_protocol = ssh1_protocol;
+ ssh_version = 1;
+ s_rdpkt = ssh1_rdpkt;
+ }
+ ssh_state = SSH_STATE_BEFORE_SIZE;
+
+ crFinish(0);
+}
+
+static void ssh_gotdata(unsigned char *data, int datalen)
+{
+ crBegin;
+
+ /*
+ * To begin with, feed the characters one by one to the
+ * protocol initialisation / selection function do_ssh_init().
+ * When that returns 0, we're done with the initial greeting
+ * exchange and can move on to packet discipline.
+ */
+ while (1) {
+ int ret;
+ if (datalen == 0)
+ crReturnV; /* more data please */
+ ret = do_ssh_init(*data);
+ data++; datalen--;
+ if (ret == 0)
+ break;
+ }
+
+ /*
+ * We emerge from that loop when the initial negotiation is
+ * over and we have selected an s_rdpkt function. Now pass
+ * everything to s_rdpkt, and then pass the resulting packets
+ * to the proper protocol handler.
+ */
+ if (datalen == 0)
+ crReturnV;
+ while (1) {
+ while (datalen > 0) {
+ if ( s_rdpkt(&data, &datalen) == 0 ) {
+ ssh_protocol(NULL, 0, 1);
+ if (ssh_state == SSH_STATE_CLOSED) {
+ return;
+ }
+ }
+ }
+ crReturnV;
+ }
+ crFinishV;
+}
+
+static int ssh_receive(Socket skt, int urgent, char *data, int len) {
+ if (urgent==3) {
+ /* A socket error has occurred. */
+ ssh_state = SSH_STATE_CLOSED;
+ sk_close(s);
+ s = NULL;
+ connection_fatal(data);
+ return 0;
+ } else if (!len) {
+ /* Connection has closed. */
+ ssh_state = SSH_STATE_CLOSED;
+ sk_close(s);
+ s = NULL;
+ return 0;
+ }
+ ssh_gotdata (data, len);
+ if (ssh_state == SSH_STATE_CLOSED) {
+ if (s) {
+ sk_close(s);
+ s = NULL;
+ }
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * Connect to specified host and port.
+ * Returns an error message, or NULL on success.
+ * Also places the canonical host name into `realhost'.
+ */
+static char *connect_to_host(char *host, int port, char **realhost)
+{
+ SockAddr addr;
+ char *err;
+#ifdef FWHACK
+ char *FWhost;
+ int FWport;
+#endif
+
+ savedhost = smalloc(1+strlen(host));
+ if (!savedhost)
+ fatalbox("Out of memory");
+ strcpy(savedhost, host);
+
+ if (port < 0)
+ port = 22; /* default ssh port */
+ savedport = port;
+
+#ifdef FWHACK
+ FWhost = host;
+ FWport = port;
+ host = FWSTR;
+ port = 23;
+#endif
+
+ /*
+ * Try to find host.
+ */
+ addr = sk_namelookup(host, realhost);
+ if ( (err = sk_addr_error(addr)) )
+ return err;
+
+#ifdef FWHACK
+ *realhost = FWhost;
+#endif
+
+ /*
+ * Open socket.
+ */
+ s = sk_new(addr, port, 0, 1, ssh_receive);
+ if ( (err = sk_socket_error(s)) )
+ return err;
+
+#ifdef FWHACK
+ sk_write(s, "connect ", 8);
+ sk_write(s, FWhost, strlen(FWhost));
+ {
+ char buf[20];
+ sprintf(buf, " %d\n", FWport);
+ sk_write(s, buf, strlen(buf));
+ }
+#endif
+
+ return NULL;
+}
+
+/*
+ * Handle the key exchange and user authentication phases.
+ */
+static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
+{
+ int i, j, len;
+ unsigned char *rsabuf, *keystr1, *keystr2;
+ unsigned char cookie[8];
+ struct RSAKey servkey, hostkey;
+ struct MD5Context md5c;
+ static unsigned long supported_ciphers_mask, supported_auths_mask;
+ static int tried_publickey;
+ static unsigned char session_id[16];
+ int cipher_type;
+ static char username[100];
+
+ crBegin;
+
+ if (!ispkt) crWaitUntil(ispkt);
+
+ if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
+ bombout(("Public key packet not received"));
+ crReturn(0);
+ }
+
+ logevent("Received public keys");
+
+ memcpy(cookie, pktin.body, 8);
+
+ i = makekey(pktin.body+8, &servkey, &keystr1, 0);
+ j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
+
+ /*
+ * Log the host key fingerprint.
+ */
+ {
+ char logmsg[80];
+ logevent("Host key fingerprint is:");
+ strcpy(logmsg, " ");
+ hostkey.comment = NULL;
+ rsa_fingerprint(logmsg+strlen(logmsg), sizeof(logmsg)-strlen(logmsg),
+ &hostkey);
+ logevent(logmsg);
+ }
+
+ supported_ciphers_mask = GET_32BIT(pktin.body+12+i+j);
+ supported_auths_mask = GET_32BIT(pktin.body+16+i+j);
+
+ MD5Init(&md5c);
+ MD5Update(&md5c, keystr2, hostkey.bytes);
+ MD5Update(&md5c, keystr1, servkey.bytes);
+ MD5Update(&md5c, pktin.body, 8);
+ MD5Final(session_id, &md5c);
- pktout.data[biglen+0] = (unsigned char) ((crc >> 24) & 0xFF);
- pktout.data[biglen+1] = (unsigned char) ((crc >> 16) & 0xFF);
- pktout.data[biglen+2] = (unsigned char) ((crc >> 8) & 0xFF);
- pktout.data[biglen+3] = (unsigned char) (crc & 0xFF);
+ for (i=0; i<32; i++)
+ session_key[i] = random_byte();
+
+ len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
+
+ rsabuf = smalloc(len);
+ if (!rsabuf)
+ fatalbox("Out of memory");
+
+ /*
+ * Verify the host key.
+ */
+ {
+ /*
+ * First format the key into a string.
+ */
+ int len = rsastr_len(&hostkey);
+ char fingerprint[100];
+ char *keystr = smalloc(len);
+ if (!keystr)
+ fatalbox("Out of memory");
+ rsastr_fmt(keystr, &hostkey);
+ rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
+ verify_ssh_host_key(savedhost, savedport, "rsa", keystr, fingerprint);
+ sfree(keystr);
+ }
+
+ for (i=0; i<32; i++) {
+ rsabuf[i] = session_key[i];
+ if (i < 16)
+ rsabuf[i] ^= session_id[i];
+ }
+
+ if (hostkey.bytes > servkey.bytes) {
+ rsaencrypt(rsabuf, 32, &servkey);
+ rsaencrypt(rsabuf, servkey.bytes, &hostkey);
+ } else {
+ rsaencrypt(rsabuf, 32, &hostkey);
+ rsaencrypt(rsabuf, hostkey.bytes, &servkey);
+ }
+
+ logevent("Encrypted session key");
+
+ cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
+ cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
+ SSH_CIPHER_3DES;
+ if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
+ c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
+ cipher_type = SSH_CIPHER_3DES;
+ }
+ switch (cipher_type) {
+ case SSH_CIPHER_3DES: logevent("Using 3DES encryption"); break;
+ case SSH_CIPHER_DES: logevent("Using single-DES encryption"); break;
+ case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
+ }
+
+ send_packet(SSH1_CMSG_SESSION_KEY,
+ PKT_CHAR, cipher_type,
+ PKT_DATA, cookie, 8,
+ PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
+ PKT_DATA, rsabuf, len,
+ PKT_INT, 0,
+ PKT_END);
+
+ logevent("Trying to enable encryption...");
+
+ sfree(rsabuf);
+
+ cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
+ cipher_type == SSH_CIPHER_DES ? &ssh_des :
+ &ssh_3des;
+ cipher->sesskey(session_key);
+
+ crWaitUntil(ispkt);
+
+ if (pktin.type != SSH1_SMSG_SUCCESS) {
+ bombout(("Encryption not successfully enabled"));
+ crReturn(0);
+ }
+
+ logevent("Successfully started encryption");
+
+ fflush(stdout);
+ {
+ static int pos = 0;
+ static char c;
+ if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
+ c_write("login as: ", 10);
+ ssh_send_ok = 1;
+ while (pos >= 0) {
+ crWaitUntil(!ispkt);
+ while (inlen--) switch (c = *in++) {
+ case 10: case 13:
+ username[pos] = 0;
+ pos = -1;
+ break;
+ case 8: case 127:
+ if (pos > 0) {
+ c_write("\b \b", 3);
+ pos--;
+ }
+ break;
+ case 21: case 27:
+ while (pos > 0) {
+ c_write("\b \b", 3);
+ pos--;
+ }
+ break;
+ case 3: case 4:
+ random_save_seed();
+ exit(0);
+ break;
+ default:
+ if (((c >= ' ' && c <= '~') ||
+ ((unsigned char)c >= 160)) && pos < 40) {
+ username[pos++] = c;
+ c_write(&c, 1);
+ }
+ break;
+ }
+ }
+ c_write("\r\n", 2);
+ username[strcspn(username, "\n\r")] = '\0';
+ } else {
+ strncpy(username, cfg.username, 99);
+ username[99] = '\0';
+ }
- pktout.data[0] = (len >> 24) & 0xFF;
- pktout.data[1] = (len >> 16) & 0xFF;
- pktout.data[2] = (len >> 8) & 0xFF;
- pktout.data[3] = len & 0xFF;
+ send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
+ {
+ char userlog[22+sizeof(username)];
+ sprintf(userlog, "Sent username \"%s\"", username);
+ logevent(userlog);
+ if (flags & FLAG_INTERACTIVE &&
+ (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
+ strcat(userlog, "\r\n");
+ c_write(userlog, strlen(userlog));
+ }
+ }
+ }
+
+ crWaitUntil(ispkt);
+
+ tried_publickey = 0;
+
+ while (pktin.type == SSH1_SMSG_FAILURE) {
+ static char password[100];
+ static char prompt[200];
+ static int pos;
+ static char c;
+ static int pwpkt_type;
+ /*
+ * Show password prompt, having first obtained it via a TIS
+ * or CryptoCard exchange if we're doing TIS or CryptoCard
+ * authentication.
+ */
+ pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
+ if (agent_exists()) {
+ /*
+ * Attempt RSA authentication using Pageant.
+ */
+ static unsigned char request[5], *response, *p;
+ static int responselen;
+ static int i, nkeys;
+ static int authed = FALSE;
+ void *r;
+
+ logevent("Pageant is running. Requesting keys.");
+
+ /* Request the keys held by the agent. */
+ PUT_32BIT(request, 1);
+ request[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
+ agent_query(request, 5, &r, &responselen);
+ response = (unsigned char *)r;
+ if (response) {
+ p = response + 5;
+ nkeys = GET_32BIT(p); p += 4;
+ { char buf[64]; sprintf(buf, "Pageant has %d keys", nkeys);
+ logevent(buf); }
+ for (i = 0; i < nkeys; i++) {
+ static struct RSAKey key;
+ static Bignum challenge;
+ static char *commentp;
+ static int commentlen;
+
+ { char buf[64]; sprintf(buf, "Trying Pageant key #%d", i);
+ logevent(buf); }
+ p += 4;
+ p += ssh1_read_bignum(p, &key.exponent);
+ p += ssh1_read_bignum(p, &key.modulus);
+ commentlen = GET_32BIT(p); p += 4;
+ commentp = p; p += commentlen;
+ send_packet(SSH1_CMSG_AUTH_RSA,
+ PKT_BIGNUM, key.modulus, PKT_END);
+ crWaitUntil(ispkt);
+ if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
+ logevent("Key refused");
+ continue;
+ }
+ logevent("Received RSA challenge");
+ ssh1_read_bignum(pktin.body, &challenge);
+ {
+ char *agentreq, *q, *ret;
+ int len, retlen;
+ len = 1 + 4; /* message type, bit count */
+ len += ssh1_bignum_length(key.exponent);
+ len += ssh1_bignum_length(key.modulus);
+ len += ssh1_bignum_length(challenge);
+ len += 16; /* session id */
+ len += 4; /* response format */
+ agentreq = smalloc(4 + len);
+ PUT_32BIT(agentreq, len);
+ q = agentreq + 4;
+ *q++ = SSH_AGENTC_RSA_CHALLENGE;
+ PUT_32BIT(q, ssh1_bignum_bitcount(key.modulus));
+ q += 4;
+ q += ssh1_write_bignum(q, key.exponent);
+ q += ssh1_write_bignum(q, key.modulus);
+ q += ssh1_write_bignum(q, challenge);
+ memcpy(q, session_id, 16); q += 16;
+ PUT_32BIT(q, 1); /* response format */
+ agent_query(agentreq, len+4, &ret, &retlen);
+ sfree(agentreq);
+ if (ret) {
+ if (ret[4] == SSH_AGENT_RSA_RESPONSE) {
+ logevent("Sending Pageant's response");
+ send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
+ PKT_DATA, ret+5, 16, PKT_END);
+ sfree(ret);
+ crWaitUntil(ispkt);
+ if (pktin.type == SSH1_SMSG_SUCCESS) {
+ logevent("Pageant's response accepted");
+ if (flags & FLAG_VERBOSE) {
+ c_write("Authenticated using RSA key \"",
+ 29);
+ c_write(commentp, commentlen);
+ c_write("\" from agent\r\n", 14);
+ }
+ authed = TRUE;
+ } else
+ logevent("Pageant's response not accepted");
+ } else {
+ logevent("Pageant failed to answer challenge");
+ sfree(ret);
+ }
+ } else {
+ logevent("No reply received from Pageant");
+ }
+ }
+ freebn(key.exponent);
+ freebn(key.modulus);
+ freebn(challenge);
+ if (authed)
+ break;
+ }
+ }
+ if (authed)
+ break;
+ }
+ if (*cfg.keyfile && !tried_publickey)
+ pwpkt_type = SSH1_CMSG_AUTH_RSA;
+
+ if (pktin.type == SSH1_SMSG_FAILURE &&
+ cfg.try_tis_auth &&
+ (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
+ pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
+ logevent("Requested TIS authentication");
+ send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
+ crWaitUntil(ispkt);
+ if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
+ logevent("TIS authentication declined");
+ if (flags & FLAG_INTERACTIVE)
+ c_write("TIS authentication refused.\r\n", 29);
+ } else {
+ int challengelen = ((pktin.body[0] << 24) |
+ (pktin.body[1] << 16) |
+ (pktin.body[2] << 8) |
+ (pktin.body[3]));
+ logevent("Received TIS challenge");
+ if (challengelen > sizeof(prompt)-1)
+ challengelen = sizeof(prompt)-1; /* prevent overrun */
+ memcpy(prompt, pktin.body+4, challengelen);
+ prompt[challengelen] = '\0';
+ }
+ }
+ if (pktin.type == SSH1_SMSG_FAILURE &&
+ cfg.try_tis_auth &&
+ (supported_auths_mask & (1<<SSH1_AUTH_CCARD))) {
+ pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
+ logevent("Requested CryptoCard authentication");
+ send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
+ crWaitUntil(ispkt);
+ if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
+ logevent("CryptoCard authentication declined");
+ c_write("CryptoCard authentication refused.\r\n", 29);
+ } else {
+ int challengelen = ((pktin.body[0] << 24) |
+ (pktin.body[1] << 16) |
+ (pktin.body[2] << 8) |
+ (pktin.body[3]));
+ logevent("Received CryptoCard challenge");
+ if (challengelen > sizeof(prompt)-1)
+ challengelen = sizeof(prompt)-1; /* prevent overrun */
+ memcpy(prompt, pktin.body+4, challengelen);
+ strncpy(prompt + challengelen, "\r\nResponse : ",
+ sizeof(prompt)-challengelen);
+ prompt[sizeof(prompt)-1] = '\0';
+ }
+ }
+ if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
+ sprintf(prompt, "%.90s@%.90s's password: ",
+ username, savedhost);
+ }
+ if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
+ char *comment = NULL;
+ if (flags & FLAG_VERBOSE)
+ c_write("Trying public key authentication.\r\n", 35);
+ if (!rsakey_encrypted(cfg.keyfile, &comment)) {
+ if (flags & FLAG_VERBOSE)
+ c_write("No passphrase required.\r\n", 25);
+ goto tryauth;
+ }
+ sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
+ sfree(comment);
+ }
+
+ if (ssh_get_password) {
+ if (!ssh_get_password(prompt, password, sizeof(password))) {
+ /*
+ * get_password failed to get a password (for
+ * example because one was supplied on the command
+ * line which has already failed to work).
+ * Terminate.
+ */
+ logevent("No more passwords to try");
+ ssh_state = SSH_STATE_CLOSED;
+ crReturn(1);
+ }
+ } else {
+ c_write(prompt, strlen(prompt));
+ pos = 0;
+ ssh_send_ok = 1;
+ while (pos >= 0) {
+ crWaitUntil(!ispkt);
+ while (inlen--) switch (c = *in++) {
+ case 10: case 13:
+ password[pos] = 0;
+ pos = -1;
+ break;
+ case 8: case 127:
+ if (pos > 0)
+ pos--;
+ break;
+ case 21: case 27:
+ pos = 0;
+ break;
+ case 3: case 4:
+ random_save_seed();
+ exit(0);
+ break;
+ default:
+ if (((c >= ' ' && c <= '~') ||
+ ((unsigned char)c >= 160)) && pos < sizeof(password))
+ password[pos++] = c;
+ break;
+ }
+ }
+ c_write("\r\n", 2);
+ }
+
+ tryauth:
+ if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
+ /*
+ * Try public key authentication with the specified
+ * key file.
+ */
+ static struct RSAKey pubkey;
+ static Bignum challenge, response;
+ static int i;
+ static unsigned char buffer[32];
+
+ tried_publickey = 1;
+ i = loadrsakey(cfg.keyfile, &pubkey, NULL, password);
+ if (i == 0) {
+ c_write("Couldn't load public key from ", 30);
+ c_write(cfg.keyfile, strlen(cfg.keyfile));
+ c_write(".\r\n", 3);
+ continue; /* go and try password */
+ }
+ if (i == -1) {
+ c_write("Wrong passphrase.\r\n", 19);
+ tried_publickey = 0;
+ continue; /* try again */
+ }
+
+ /*
+ * Send a public key attempt.
+ */
+ send_packet(SSH1_CMSG_AUTH_RSA,
+ PKT_BIGNUM, pubkey.modulus, PKT_END);
+
+ crWaitUntil(ispkt);
+ if (pktin.type == SSH1_SMSG_FAILURE) {
+ c_write("Server refused our public key.\r\n", 32);
+ continue; /* go and try password */
+ }
+ if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
+ bombout(("Bizarre response to offer of public key"));
+ crReturn(0);
+ }
+ ssh1_read_bignum(pktin.body, &challenge);
+ response = rsadecrypt(challenge, &pubkey);
+ freebn(pubkey.private_exponent); /* burn the evidence */
+
+ for (i = 0; i < 32; i += 2) {
+ buffer[i] = response[16-i/2] >> 8;
+ buffer[i+1] = response[16-i/2] & 0xFF;
+ }
+
+ MD5Init(&md5c);
+ MD5Update(&md5c, buffer, 32);
+ MD5Update(&md5c, session_id, 16);
+ MD5Final(buffer, &md5c);
+
+ send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
+ PKT_DATA, buffer, 16, PKT_END);
+
+ crWaitUntil(ispkt);
+ if (pktin.type == SSH1_SMSG_FAILURE) {
+ if (flags & FLAG_VERBOSE)
+ c_write("Failed to authenticate with our public key.\r\n",
+ 45);
+ continue; /* go and try password */
+ } else if (pktin.type != SSH1_SMSG_SUCCESS) {
+ bombout(("Bizarre response to RSA authentication response"));
+ crReturn(0);
+ }
+
+ break; /* we're through! */
+ } else {
+ send_packet(pwpkt_type, PKT_STR, password, PKT_END);
+ }
+ logevent("Sent password");
+ memset(password, 0, strlen(password));
+ crWaitUntil(ispkt);
+ if (pktin.type == SSH1_SMSG_FAILURE) {
+ if (flags & FLAG_VERBOSE)
+ c_write("Access denied\r\n", 15);
+ logevent("Authentication refused");
+ } else if (pktin.type == SSH1_MSG_DISCONNECT) {
+ logevent("Received disconnect request");
+ ssh_state = SSH_STATE_CLOSED;
+ crReturn(1);
+ } else if (pktin.type != SSH1_SMSG_SUCCESS) {
+ bombout(("Strange packet received, type %d", pktin.type));
+ crReturn(0);
+ }
+ }
+
+ logevent("Authentication successful");
+
+ crFinish(1);
+}
+
+void sshfwd_close(struct ssh_channel *c) {
+ if (c) {
+ if (ssh_version == 1) {
+ send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid, PKT_END);
+ } else {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_send();
+ }
+ c->closes = 1;
+ if (c->type == CHAN_X11) {
+ c->u.x11.s = NULL;
+ logevent("X11 connection terminated");
+ }
+ }
+}
+
+void sshfwd_write(struct ssh_channel *c, char *buf, int len) {
+ if (ssh_version == 1) {
+ send_packet(SSH1_MSG_CHANNEL_DATA,
+ PKT_INT, c->remoteid,
+ PKT_INT, len,
+ PKT_DATA, buf, len,
+ PKT_END);
+ } else {
+ ssh2_add_channel_data(c, buf, len);
+ ssh2_try_send(c);
+ }
+}
+
+static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
+ crBegin;
+
+ random_init();
+
+ while (!do_ssh1_login(in, inlen, ispkt)) {
+ crReturnV;
+ }
+ if (ssh_state == SSH_STATE_CLOSED)
+ crReturnV;
+
+ if (cfg.agentfwd && agent_exists()) {
+ logevent("Requesting agent forwarding");
+ send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
+ do { crReturnV; } while (!ispkt);
+ if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crReturnV;
+ } else if (pktin.type == SSH1_SMSG_FAILURE) {
+ logevent("Agent forwarding refused");
+ } else {
+ logevent("Agent forwarding enabled");
+ ssh_agentfwd_enabled = TRUE;
+ }
+ }
+
+ if (cfg.x11_forward) {
+ char proto[20], data[64];
+ logevent("Requesting X11 forwarding");
+ x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
+ send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING,
+ PKT_STR, proto, PKT_STR, data,
+ PKT_INT, 0,
+ PKT_END);
+ do { crReturnV; } while (!ispkt);
+ if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crReturnV;
+ } else if (pktin.type == SSH1_SMSG_FAILURE) {
+ logevent("X11 forwarding refused");
+ } else {
+ logevent("X11 forwarding enabled");
+ ssh_X11_fwd_enabled = TRUE;
+ }
+ }
+
+ if (!cfg.nopty) {
+ send_packet(SSH1_CMSG_REQUEST_PTY,
+ PKT_STR, cfg.termtype,
+ PKT_INT, rows, PKT_INT, cols,
+ PKT_INT, 0, PKT_INT, 0,
+ PKT_CHAR, 0,
+ PKT_END);
+ ssh_state = SSH_STATE_INTERMED;
+ do { crReturnV; } while (!ispkt);
+ if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crReturnV;
+ } else if (pktin.type == SSH1_SMSG_FAILURE) {
+ c_write("Server refused to allocate pty\r\n", 32);
+ ssh_editing = ssh_echoing = 1;
+ }
+ logevent("Allocated pty");
+ } else {
+ ssh_editing = ssh_echoing = 1;
+ }
- if (cipher)
- cipher->encrypt(pktout.data+4, biglen);
+ if (cfg.compression) {
+ send_packet(SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
+ do { crReturnV; } while (!ispkt);
+ if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crReturnV;
+ } else if (pktin.type == SSH1_SMSG_FAILURE) {
+ c_write("Server refused to compress\r\n", 32);
+ }
+ logevent("Started compression");
+ ssh1_compressing = TRUE;
+ zlib_compress_init();
+ zlib_decompress_init();
+ }
- s_write(pktout.data, biglen+4);
-}
+ if (*cfg.remote_cmd)
+ send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd, PKT_END);
+ else
+ send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
+ logevent("Started session");
-static int do_ssh_init(void) {
- char c;
- char version[10];
- char vstring[40];
- int i;
+ ssh_state = SSH_STATE_SESSION;
+ if (size_needed)
+ ssh_size();
+ if (eof_needed)
+ ssh_special(TS_EOF);
-#ifdef FWHACK
- i = 0;
- while (s_read(&c, 1) == 1) {
- if (c == 'S' && i < 2) i++;
- else if (c == 'S' && i == 2) i = 2;
- else if (c == 'H' && i == 2) break;
- else i = 0;
- }
-#else
- if (s_read(&c,1) != 1 || c != 'S') return 0;
- if (s_read(&c,1) != 1 || c != 'S') return 0;
- if (s_read(&c,1) != 1 || c != 'H') return 0;
-#endif
- if (s_read(&c,1) != 1 || c != '-') return 0;
- i = 0;
+ ldisc_send(NULL, 0); /* cause ldisc to notice changes */
+ ssh_send_ok = 1;
+ ssh_channels = newtree234(ssh_channelcmp);
while (1) {
- if (s_read(&c,1) != 1)
- return 0;
- if (i >= 0) {
- if (c == '-') {
- version[i] = '\0';
- i = -1;
- } else if (i < sizeof(version)-1)
- version[i++] = c;
+ crReturnV;
+ if (ispkt) {
+ if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
+ pktin.type == SSH1_SMSG_STDERR_DATA) {
+ long len = GET_32BIT(pktin.body);
+ from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
+ pktin.body+4, len);
+ } else if (pktin.type == SSH1_MSG_DISCONNECT) {
+ ssh_state = SSH_STATE_CLOSED;
+ logevent("Received disconnect request");
+ crReturnV;
+ } else if (pktin.type == SSH1_SMSG_X11_OPEN) {
+ /* Remote side is trying to open a channel to talk to our
+ * X-Server. Give them back a local channel number. */
+ unsigned i;
+ struct ssh_channel *c, *d;
+ enum234 e;
+
+ logevent("Received X11 connect request");
+ /* Refuse if X11 forwarding is disabled. */
+ if (!ssh_X11_fwd_enabled) {
+ send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, GET_32BIT(pktin.body),
+ PKT_END);
+ logevent("Rejected X11 connect request");
+ } else {
+ c = smalloc(sizeof(struct ssh_channel));
+
+ if ( x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL ) {
+ logevent("opening X11 forward connection failed");
+ sfree(c);
+ send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, GET_32BIT(pktin.body),
+ PKT_END);
+ } else {
+ logevent("opening X11 forward connection succeeded");
+ for (i=1, d = first234(ssh_channels, &e); d; d = next234(&e)) {
+ if (d->localid > i)
+ break; /* found a free number */
+ i = d->localid + 1;
+ }
+ c->remoteid = GET_32BIT(pktin.body);
+ c->localid = i;
+ c->closes = 0;
+ c->type = CHAN_X11; /* identify channel type */
+ add234(ssh_channels, c);
+ send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT, c->localid,
+ PKT_END);
+ logevent("Opened X11 forward channel");
+ }
+ }
+ } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
+ /* Remote side is trying to open a channel to talk to our
+ * agent. Give them back a local channel number. */
+ unsigned i;
+ struct ssh_channel *c;
+ enum234 e;
+
+ /* Refuse if agent forwarding is disabled. */
+ if (!ssh_agentfwd_enabled) {
+ send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, GET_32BIT(pktin.body),
+ PKT_END);
+ } else {
+ i = 1;
+ for (c = first234(ssh_channels, &e); c; c = next234(&e)) {
+ if (c->localid > i)
+ break; /* found a free number */
+ i = c->localid + 1;
+ }
+ c = smalloc(sizeof(struct ssh_channel));
+ c->remoteid = GET_32BIT(pktin.body);
+ c->localid = i;
+ c->closes = 0;
+ c->type = CHAN_AGENT; /* identify channel type */
+ c->u.a.lensofar = 0;
+ add234(ssh_channels, c);
+ send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT, c->localid,
+ PKT_END);
+ }
+ } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
+ pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
+ /* Remote side closes a channel. */
+ unsigned i = GET_32BIT(pktin.body);
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (c) {
+ int closetype;
+ closetype = (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
+ send_packet(pktin.type, PKT_INT, c->remoteid, PKT_END);
+ if ((c->closes == 0) && (c->type == CHAN_X11)) {
+ logevent("X11 connection closed");
+ assert(c->u.x11.s != NULL);
+ x11_close(c->u.x11.s);
+ c->u.x11.s = NULL;
+ }
+ c->closes |= closetype;
+ if (c->closes == 3) {
+ del234(ssh_channels, c);
+ sfree(c);
+ }
+ }
+ } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
+ /* Data sent down one of our channels. */
+ int i = GET_32BIT(pktin.body);
+ int len = GET_32BIT(pktin.body+4);
+ unsigned char *p = pktin.body+8;
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (c) {
+ switch(c->type) {
+ case CHAN_X11:
+ x11_send(c->u.x11.s, p, len);
+ break;
+ case CHAN_AGENT:
+ /* Data for an agent message. Buffer it. */
+ while (len > 0) {
+ if (c->u.a.lensofar < 4) {
+ int l = min(4 - c->u.a.lensofar, len);
+ memcpy(c->u.a.msglen + c->u.a.lensofar, p, l);
+ p += l; len -= l; c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == 4) {
+ c->u.a.totallen = 4 + GET_32BIT(c->u.a.msglen);
+ c->u.a.message = smalloc(c->u.a.totallen);
+ memcpy(c->u.a.message, c->u.a.msglen, 4);
+ }
+ if (c->u.a.lensofar >= 4 && len > 0) {
+ int l = min(c->u.a.totallen - c->u.a.lensofar, len);
+ memcpy(c->u.a.message + c->u.a.lensofar, p, l);
+ p += l; len -= l; c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == c->u.a.totallen) {
+ void *reply, *sentreply;
+ int replylen;
+ agent_query(c->u.a.message, c->u.a.totallen,
+ &reply, &replylen);
+ if (reply)
+ sentreply = reply;
+ else {
+ /* Fake SSH_AGENT_FAILURE. */
+ sentreply = "\0\0\0\1\5";
+ replylen = 5;
+ }
+ send_packet(SSH1_MSG_CHANNEL_DATA,
+ PKT_INT, c->remoteid,
+ PKT_INT, replylen,
+ PKT_DATA, sentreply, replylen,
+ PKT_END);
+ if (reply)
+ sfree(reply);
+ sfree(c->u.a.message);
+ c->u.a.lensofar = 0;
+ }
+ }
+ break;
+ }
+ }
+ } else if (pktin.type == SSH1_SMSG_SUCCESS) {
+ /* may be from EXEC_SHELL on some servers */
+ } else if (pktin.type == SSH1_SMSG_FAILURE) {
+ /* may be from EXEC_SHELL on some servers
+ * if no pty is available or in other odd cases. Ignore */
+ } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
+ send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
+ } else {
+ bombout(("Strange packet received: type %d", pktin.type));
+ crReturnV;
+ }
+ } else {
+ while (inlen > 0) {
+ int len = min(inlen, 512);
+ send_packet(SSH1_CMSG_STDIN_DATA,
+ PKT_INT, len, PKT_DATA, in, len, PKT_END);
+ in += len;
+ inlen -= len;
+ }
}
- else if (c == '\n')
- break;
}
- sprintf(vstring, "SSH-%s-7.7.7\n",
- (strcmp(version, "1.5") <= 0 ? version : "1.5"));
- s_write(vstring, strlen(vstring));
+ crFinishV;
}
-static void ssh_protocol(unsigned char *in, int inlen, int ispkt) {
- int i, j, len;
- unsigned char session_id[16];
- unsigned char *rsabuf, *keystr1, *keystr2;
- unsigned char cookie[8];
- struct RSAKey servkey, hostkey;
- struct MD5Context md5c;
+/*
+ * Utility routine for decoding comma-separated strings in KEXINIT.
+ */
+static int in_commasep_string(char *needle, char *haystack, int haylen) {
+ int needlen = strlen(needle);
+ while (1) {
+ /*
+ * Is it at the start of the string?
+ */
+ if (haylen >= needlen && /* haystack is long enough */
+ !memcmp(needle, haystack, needlen) && /* initial match */
+ (haylen == needlen || haystack[needlen] == ',')
+ /* either , or EOS follows */
+ )
+ return 1;
+ /*
+ * If not, search for the next comma and resume after that.
+ * If no comma found, terminate.
+ */
+ while (haylen > 0 && *haystack != ',')
+ haylen--, haystack++;
+ if (haylen == 0)
+ return 0;
+ haylen--, haystack++; /* skip over comma itself */
+ }
+}
+
+/*
+ * SSH2 key creation method.
+ */
+static void ssh2_mkkey(Bignum K, char *H, char *sessid, char chr, char *keyspace) {
+ SHA_State s;
+ /* First 20 bytes. */
+ SHA_Init(&s);
+ sha_mpint(&s, K);
+ SHA_Bytes(&s, H, 20);
+ SHA_Bytes(&s, &chr, 1);
+ SHA_Bytes(&s, sessid, 20);
+ SHA_Final(&s, keyspace);
+ /* Next 20 bytes. */
+ SHA_Init(&s);
+ sha_mpint(&s, K);
+ SHA_Bytes(&s, H, 20);
+ SHA_Bytes(&s, keyspace, 20);
+ SHA_Final(&s, keyspace+20);
+}
- extern struct ssh_cipher ssh_3des;
+/*
+ * Handle the SSH2 transport layer.
+ */
+static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
+{
+ static int i, len;
+ static char *str;
+ static Bignum e, f, K;
+ static const struct ssh_mac **maclist;
+ static int nmacs;
+ static const struct ssh_cipher *cscipher_tobe = NULL;
+ static const struct ssh_cipher *sccipher_tobe = NULL;
+ static const struct ssh_mac *csmac_tobe = NULL;
+ static const struct ssh_mac *scmac_tobe = NULL;
+ static const struct ssh_compress *cscomp_tobe = NULL;
+ static const struct ssh_compress *sccomp_tobe = NULL;
+ static char *hostkeydata, *sigdata, *keystr, *fingerprint;
+ static int hostkeylen, siglen;
+ static void *hkey; /* actual host key */
+ static unsigned char exchange_hash[20];
+ static unsigned char first_exchange_hash[20];
+ static unsigned char keyspace[40];
+ static const struct ssh_cipher *preferred_cipher;
+ static const struct ssh_compress *preferred_comp;
+ static int first_kex;
crBegin;
-
random_init();
+ first_kex = 1;
- while (!ispkt)
- crReturnV;
+ /*
+ * Set up the preferred cipher and compression.
+ */
+ if (cfg.cipher == CIPHER_BLOWFISH) {
+ preferred_cipher = &ssh_blowfish_ssh2;
+ } else if (cfg.cipher == CIPHER_DES) {
+ logevent("Single DES not supported in SSH2; using 3DES");
+ preferred_cipher = &ssh_3des_ssh2;
+ } else if (cfg.cipher == CIPHER_3DES) {
+ preferred_cipher = &ssh_3des_ssh2;
+ } else {
+ /* Shouldn't happen, but we do want to initialise to _something_. */
+ preferred_cipher = &ssh_3des_ssh2;
+ }
+ if (cfg.compression)
+ preferred_comp = &ssh_zlib;
+ else
+ preferred_comp = &ssh_comp_none;
- if (pktin.type != 2)
- fatalbox("Public key packet not received");
+ /*
+ * Be prepared to work around the buggy MAC problem.
+ */
+ if (cfg.buggymac)
+ maclist = buggymacs, nmacs = lenof(buggymacs);
+ else
+ maclist = macs, nmacs = lenof(macs);
- memcpy(cookie, pktin.body, 8);
+ begin_key_exchange:
+ /*
+ * Construct and send our key exchange packet.
+ */
+ ssh2_pkt_init(SSH2_MSG_KEXINIT);
+ for (i = 0; i < 16; i++)
+ ssh2_pkt_addbyte((unsigned char)random_byte());
+ /* List key exchange algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(kex_algs); i++) {
+ ssh2_pkt_addstring_str(kex_algs[i]->name);
+ if (i < lenof(kex_algs)-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List server host key algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(hostkey_algs); i++) {
+ ssh2_pkt_addstring_str(hostkey_algs[i]->name);
+ if (i < lenof(hostkey_algs)-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List client->server encryption algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(ciphers)+1; i++) {
+ const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
+ ssh2_pkt_addstring_str(c->name);
+ if (i < lenof(ciphers))
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List server->client encryption algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(ciphers)+1; i++) {
+ const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
+ ssh2_pkt_addstring_str(c->name);
+ if (i < lenof(ciphers))
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List client->server MAC algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < nmacs; i++) {
+ ssh2_pkt_addstring_str(maclist[i]->name);
+ if (i < nmacs-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List server->client MAC algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < nmacs; i++) {
+ ssh2_pkt_addstring_str(maclist[i]->name);
+ if (i < nmacs-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List client->server compression algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(compressions)+1; i++) {
+ const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1];
+ ssh2_pkt_addstring_str(c->name);
+ if (i < lenof(compressions))
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List server->client compression algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(compressions)+1; i++) {
+ const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1];
+ ssh2_pkt_addstring_str(c->name);
+ if (i < lenof(compressions))
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List client->server languages. Empty list. */
+ ssh2_pkt_addstring_start();
+ /* List server->client languages. Empty list. */
+ ssh2_pkt_addstring_start();
+ /* First KEX packet does _not_ follow, because we're not that brave. */
+ ssh2_pkt_addbool(FALSE);
+ /* Reserved. */
+ ssh2_pkt_adduint32(0);
- MD5Init(&md5c);
+ exhash = exhashbase;
+ sha_string(&exhash, pktout.data+5, pktout.length-5);
- i = makekey(pktin.body+8, &servkey, &keystr1);
+ ssh2_pkt_send();
- j = makekey(pktin.body+8+i, &hostkey, &keystr2);
+ if (!ispkt) crWaitUntil(ispkt);
+ sha_string(&exhash, pktin.data+5, pktin.length-5);
- MD5Update(&md5c, keystr2, hostkey.bytes);
- MD5Update(&md5c, keystr1, servkey.bytes);
- MD5Update(&md5c, pktin.body, 8);
+ /*
+ * Now examine the other side's KEXINIT to see what we're up
+ * to.
+ */
+ if (pktin.type != SSH2_MSG_KEXINIT) {
+ bombout(("expected key exchange packet from server"));
+ crReturn(0);
+ }
+ kex = NULL; hostkey = NULL; cscipher_tobe = NULL; sccipher_tobe = NULL;
+ csmac_tobe = NULL; scmac_tobe = NULL; cscomp_tobe = NULL; sccomp_tobe = NULL;
+ pktin.savedpos += 16; /* skip garbage cookie */
+ ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
+ for (i = 0; i < lenof(kex_algs); i++) {
+ if (in_commasep_string(kex_algs[i]->name, str, len)) {
+ kex = kex_algs[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* host key algorithms */
+ for (i = 0; i < lenof(hostkey_algs); i++) {
+ if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
+ hostkey = hostkey_algs[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* client->server cipher */
+ for (i = 0; i < lenof(ciphers)+1; i++) {
+ const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
+ if (in_commasep_string(c->name, str, len)) {
+ cscipher_tobe = c;
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* server->client cipher */
+ for (i = 0; i < lenof(ciphers)+1; i++) {
+ const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
+ if (in_commasep_string(c->name, str, len)) {
+ sccipher_tobe = c;
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* client->server mac */
+ for (i = 0; i < nmacs; i++) {
+ if (in_commasep_string(maclist[i]->name, str, len)) {
+ csmac_tobe = maclist[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* server->client mac */
+ for (i = 0; i < nmacs; i++) {
+ if (in_commasep_string(maclist[i]->name, str, len)) {
+ scmac_tobe = maclist[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* client->server compression */
+ for (i = 0; i < lenof(compressions)+1; i++) {
+ const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1];
+ if (in_commasep_string(c->name, str, len)) {
+ cscomp_tobe = c;
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* server->client compression */
+ for (i = 0; i < lenof(compressions)+1; i++) {
+ const struct ssh_compress *c = i==0 ? preferred_comp : compressions[i-1];
+ if (in_commasep_string(c->name, str, len)) {
+ sccomp_tobe = c;
+ break;
+ }
+ }
- MD5Final(session_id, &md5c);
+ /*
+ * Currently we only support Diffie-Hellman and DSS, so let's
+ * bomb out if those aren't selected.
+ */
+ if (kex != &ssh_diffiehellman || hostkey != &ssh_dss) {
+ bombout(("internal fault: chaos in SSH 2 transport layer"));
+ crReturn(0);
+ }
- for (i=0; i<32; i++)
- session_key[i] = random_byte();
+ /*
+ * Now we begin the fun. Generate and send e for Diffie-Hellman.
+ */
+ e = dh_create_e();
+ ssh2_pkt_init(SSH2_MSG_KEXDH_INIT);
+ ssh2_pkt_addmp(e);
+ ssh2_pkt_send();
+
+ crWaitUntil(ispkt);
+ if (pktin.type != SSH2_MSG_KEXDH_REPLY) {
+ bombout(("expected key exchange packet from server"));
+ crReturn(0);
+ }
+ ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
+ f = ssh2_pkt_getmp();
+ ssh2_pkt_getstring(&sigdata, &siglen);
+
+ K = dh_find_K(f);
+
+ sha_string(&exhash, hostkeydata, hostkeylen);
+ sha_mpint(&exhash, e);
+ sha_mpint(&exhash, f);
+ sha_mpint(&exhash, K);
+ SHA_Final(&exhash, exchange_hash);
+
+#if 0
+ debug(("Exchange hash is:\r\n"));
+ for (i = 0; i < 20; i++)
+ debug((" %02x", exchange_hash[i]));
+ debug(("\r\n"));
+#endif
- len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
+ hkey = hostkey->newkey(hostkeydata, hostkeylen);
+ if (!hostkey->verifysig(hkey, sigdata, siglen, exchange_hash, 20)) {
+ bombout(("Server failed host key check"));
+ crReturn(0);
+ }
- rsabuf = malloc(len);
- if (!rsabuf)
- fatalbox("Out of memory");
+ /*
+ * Expect SSH2_MSG_NEWKEYS from server.
+ */
+ crWaitUntil(ispkt);
+ if (pktin.type != SSH2_MSG_NEWKEYS) {
+ bombout(("expected new-keys packet from server"));
+ crReturn(0);
+ }
- verify_ssh_host_key(savedhost, &hostkey);
+ /*
+ * Authenticate remote host: verify host key. (We've already
+ * checked the signature of the exchange hash.)
+ */
+ keystr = hostkey->fmtkey(hkey);
+ fingerprint = hostkey->fingerprint(hkey);
+ verify_ssh_host_key(savedhost, savedport, hostkey->keytype,
+ keystr, fingerprint);
+ if (first_kex) { /* don't bother logging this in rekeys */
+ logevent("Host key fingerprint is:");
+ logevent(fingerprint);
+ }
+ sfree(fingerprint);
+ sfree(keystr);
+ hostkey->freekey(hkey);
- for (i=0; i<32; i++) {
- rsabuf[i] = session_key[i];
- if (i < 16)
- rsabuf[i] ^= session_id[i];
+ /*
+ * Send SSH2_MSG_NEWKEYS.
+ */
+ ssh2_pkt_init(SSH2_MSG_NEWKEYS);
+ ssh2_pkt_send();
+
+ /*
+ * Create and initialise session keys.
+ */
+ cscipher = cscipher_tobe;
+ sccipher = sccipher_tobe;
+ csmac = csmac_tobe;
+ scmac = scmac_tobe;
+ cscomp = cscomp_tobe;
+ sccomp = sccomp_tobe;
+ cscomp->compress_init();
+ sccomp->decompress_init();
+ /*
+ * Set IVs after keys. Here we use the exchange hash from the
+ * _first_ key exchange.
+ */
+ if (first_kex)
+ memcpy(first_exchange_hash, exchange_hash, sizeof(exchange_hash));
+ ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'C', keyspace);
+ cscipher->setcskey(keyspace);
+ ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'D', keyspace);
+ sccipher->setsckey(keyspace);
+ ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'A', keyspace);
+ cscipher->setcsiv(keyspace);
+ ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'B', keyspace);
+ sccipher->setsciv(keyspace);
+ ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'E', keyspace);
+ csmac->setcskey(keyspace);
+ ssh2_mkkey(K, exchange_hash, first_exchange_hash, 'F', keyspace);
+ scmac->setsckey(keyspace);
+
+ /*
+ * If this is the first key exchange phase, we must pass the
+ * SSH2_MSG_NEWKEYS packet to the next layer, not because it
+ * wants to see it but because it will need time to initialise
+ * itself before it sees an actual packet. In subsequent key
+ * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
+ * it would only confuse the layer above.
+ */
+ if (!first_kex) {
+ crReturn(0);
}
+ first_kex = 0;
- if (hostkey.bytes > servkey.bytes) {
- rsaencrypt(rsabuf, 32, &servkey);
- rsaencrypt(rsabuf, servkey.bytes, &hostkey);
- } else {
- rsaencrypt(rsabuf, 32, &hostkey);
- rsaencrypt(rsabuf, hostkey.bytes, &servkey);
+ /*
+ * Now we're encrypting. Begin returning 1 to the protocol main
+ * function so that other things can run on top of the
+ * transport. If we ever see a KEXINIT, we must go back to the
+ * start.
+ */
+ while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT)) {
+ crReturn(1);
}
+ logevent("Server initiated key re-exchange");
+ goto begin_key_exchange;
- s_wrpkt_start(3, len+15);
- pktout.body[0] = 3; /* SSH_CIPHER_3DES */
- memcpy(pktout.body+1, cookie, 8);
- pktout.body[9] = (len*8) >> 8;
- pktout.body[10] = (len*8) & 0xFF;
- memcpy(pktout.body+11, rsabuf, len);
- pktout.body[len+11] = pktout.body[len+12] = 0; /* protocol flags */
- pktout.body[len+13] = pktout.body[len+14] = 0;
- s_wrpkt();
+ crFinish(1);
+}
- free(rsabuf);
+/*
+ * Add data to an SSH2 channel output buffer.
+ */
+static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len) {
+ if (c->v2.outbufsize <
+ c->v2.outbuflen + len) {
+ c->v2.outbufsize =
+ c->v2.outbuflen + len + 1024;
+ c->v2.outbuffer = srealloc(c->v2.outbuffer,
+ c->v2.outbufsize);
+ }
+ memcpy(c->v2.outbuffer + c->v2.outbuflen,
+ buf, len);
+ c->v2.outbuflen += len;
+}
- cipher = &ssh_3des;
- cipher->sesskey(session_key);
+/*
+ * Attempt to send data on an SSH2 channel.
+ */
+static void ssh2_try_send(struct ssh_channel *c) {
+ while (c->v2.remwindow > 0 &&
+ c->v2.outbuflen > 0) {
+ unsigned len = c->v2.remwindow;
+ if (len > c->v2.outbuflen)
+ len = c->v2.outbuflen;
+ if (len > c->v2.remmaxpkt)
+ len = c->v2.remmaxpkt;
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_addstring_data(c->v2.outbuffer, len);
+ ssh2_pkt_send();
+ c->v2.outbuflen -= len;
+ memmove(c->v2.outbuffer, c->v2.outbuffer+len,
+ c->v2.outbuflen);
+ c->v2.remwindow -= len;
+ }
+}
- do { crReturnV; } while (!ispkt);
+/*
+ * Handle the SSH2 userauth and connection layers.
+ */
+static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
+{
+ static unsigned long remote_winsize;
+ static unsigned long remote_maxpkt;
- if (pktin.type != 14)
- fatalbox("Encryption not successfully enabled");
+ crBegin;
- fflush(stdout);
- {
+ /*
+ * Request userauth protocol, and await a response to it.
+ */
+ ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
+ ssh2_pkt_addstring("ssh-userauth");
+ ssh2_pkt_send();
+ crWaitUntilV(ispkt);
+ if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
+ bombout(("Server refused user authentication protocol"));
+ crReturnV;
+ }
+
+ /*
+ * FIXME: currently we support only password authentication.
+ * (This places us technically in violation of the SSH2 spec.
+ * We must fix this.)
+ */
+ while (1) {
+ /*
+ * Get a username and a password.
+ */
static char username[100];
+ static char password[100];
static int pos = 0;
static char c;
- if (!*cfg.username) {
+
+ if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
c_write("login as: ", 10);
+ ssh_send_ok = 1;
while (pos >= 0) {
- do { crReturnV; } while (ispkt);
+ crWaitUntilV(!ispkt);
while (inlen--) switch (c = *in++) {
case 10: case 13:
username[pos] = 0;
exit(0);
break;
default:
- if (c >= ' ' && c <= '~' && pos < 40) {
+ if (((c >= ' ' && c <= '~') ||
+ ((unsigned char)c >= 160)) && pos < 40) {
username[pos++] = c;
c_write(&c, 1);
}
char stuff[200];
strncpy(username, cfg.username, 99);
username[99] = '\0';
- sprintf(stuff, "Sent username \"%s\".\r\n", username);
- c_write(stuff, strlen(stuff));
+ if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
+ sprintf(stuff, "Using username \"%s\".\r\n", username);
+ c_write(stuff, strlen(stuff));
+ }
}
- s_wrpkt_start(4, 4+strlen(username));
- pktout.body[0] = pktout.body[1] = pktout.body[2] = 0;
- pktout.body[3] = strlen(username);
- memcpy(pktout.body+4, username, strlen(username));
- s_wrpkt();
- }
-
- do { crReturnV; } while (!ispkt);
- while (pktin.type == 15) {
- static char password[100];
- static int pos;
- static char c;
- c_write("password: ", 10);
- pos = 0;
- while (pos >= 0) {
- do { crReturnV; } while (ispkt);
- while (inlen--) switch (c = *in++) {
- case 10: case 13:
- password[pos] = 0;
- pos = -1;
- break;
- case 8: case 127:
- if (pos > 0)
- pos--;
- break;
- case 21: case 27:
- pos = 0;
- break;
- case 3: case 4:
- random_save_seed();
- exit(0);
- break;
- default:
- if (c >= ' ' && c <= '~' && pos < 40)
- password[pos++] = c;
- break;
- }
+ if (ssh_get_password) {
+ char prompt[200];
+ sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost);
+ if (!ssh_get_password(prompt, password, sizeof(password))) {
+ /*
+ * get_password failed to get a password (for
+ * example because one was supplied on the command
+ * line which has already failed to work).
+ * Terminate.
+ */
+ logevent("No more passwords to try");
+ ssh_state = SSH_STATE_CLOSED;
+ crReturnV;
+ }
+ } else {
+ c_write("password: ", 10);
+ ssh_send_ok = 1;
+
+ pos = 0;
+ while (pos >= 0) {
+ crWaitUntilV(!ispkt);
+ while (inlen--) switch (c = *in++) {
+ case 10: case 13:
+ password[pos] = 0;
+ pos = -1;
+ break;
+ case 8: case 127:
+ if (pos > 0)
+ pos--;
+ break;
+ case 21: case 27:
+ pos = 0;
+ break;
+ case 3: case 4:
+ random_save_seed();
+ exit(0);
+ break;
+ default:
+ if (((c >= ' ' && c <= '~') ||
+ ((unsigned char)c >= 160)) && pos < 40)
+ password[pos++] = c;
+ break;
+ }
+ }
+ c_write("\r\n", 2);
}
- c_write("\r\n", 2);
- s_wrpkt_start(9, 4+strlen(password));
- pktout.body[0] = pktout.body[1] = pktout.body[2] = 0;
- pktout.body[3] = strlen(password);
- memcpy(pktout.body+4, password, strlen(password));
- s_wrpkt();
- memset(password, 0, strlen(password));
- do { crReturnV; } while (!ispkt);
- if (pktin.type == 15) {
+
+ ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(username);
+ ssh2_pkt_addstring("ssh-connection"); /* service requested */
+ ssh2_pkt_addstring("password");
+ ssh2_pkt_addbool(FALSE);
+ ssh2_pkt_addstring(password);
+ ssh2_pkt_send();
+
+ crWaitUntilV(ispkt);
+ if (pktin.type != SSH2_MSG_USERAUTH_SUCCESS) {
c_write("Access denied\r\n", 15);
- } else if (pktin.type != 14) {
- fatalbox("Strange packet received, type %d", pktin.type);
- }
+ logevent("Authentication refused");
+ } else
+ break;
}
- i = strlen(cfg.termtype);
- s_wrpkt_start(10, i+5*4+1);
- pktout.body[0] = (i >> 24) & 0xFF;
- pktout.body[1] = (i >> 16) & 0xFF;
- pktout.body[2] = (i >> 8) & 0xFF;
- pktout.body[3] = i & 0xFF;
- memcpy(pktout.body+4, cfg.termtype, i);
- i += 4;
- pktout.body[i++] = (rows >> 24) & 0xFF;
- pktout.body[i++] = (rows >> 16) & 0xFF;
- pktout.body[i++] = (rows >> 8) & 0xFF;
- pktout.body[i++] = rows & 0xFF;
- pktout.body[i++] = (cols >> 24) & 0xFF;
- pktout.body[i++] = (cols >> 16) & 0xFF;
- pktout.body[i++] = (cols >> 8) & 0xFF;
- pktout.body[i++] = cols & 0xFF;
- memset(pktout.body+i, 0, 9); /* 0 pixwidth, 0 pixheight, 0.b endofopt */
- s_wrpkt();
- ssh_state = SSH_STATE_INTERMED;
- do { crReturnV; } while (!ispkt);
- if (pktin.type != 14 && pktin.type != 15) {
- fatalbox("Protocol confusion");
- } else if (pktin.type == 15) {
- c_write("Server refused to allocate pty\r\n", 32);
+ /*
+ * Now we're authenticated for the connection protocol. The
+ * connection protocol will automatically have started at this
+ * point; there's no need to send SERVICE_REQUEST.
+ */
+
+ /*
+ * So now create a channel with a session in it.
+ */
+ mainchan = smalloc(sizeof(struct ssh_channel));
+ mainchan->localid = 100; /* as good as any */
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
+ ssh2_pkt_addstring("session");
+ ssh2_pkt_adduint32(mainchan->localid);
+ ssh2_pkt_adduint32(0x8000UL); /* our window size */
+ ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
+ ssh2_pkt_send();
+ crWaitUntilV(ispkt);
+ if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
+ bombout(("Server refused to open a session"));
+ crReturnV;
+ /* FIXME: error data comes back in FAILURE packet */
+ }
+ if (ssh2_pkt_getuint32() != mainchan->localid) {
+ bombout(("Server's channel confirmation cited wrong channel"));
+ crReturnV;
}
+ mainchan->remoteid = ssh2_pkt_getuint32();
+ mainchan->type = CHAN_MAINSESSION;
+ mainchan->closes = 0;
+ mainchan->v2.remwindow = ssh2_pkt_getuint32();
+ mainchan->v2.remmaxpkt = ssh2_pkt_getuint32();
+ mainchan->v2.outbuffer = NULL;
+ mainchan->v2.outbuflen = mainchan->v2.outbufsize = 0;
+ ssh_channels = newtree234(ssh_channelcmp);
+ add234(ssh_channels, mainchan);
+ logevent("Opened channel for session");
- s_wrpkt_start(12, 0);
- s_wrpkt();
+ /*
+ * Potentially enable X11 forwarding.
+ */
+ if (cfg.x11_forward) {
+ char proto[20], data[64];
+ logevent("Requesting X11 forwarding");
+ x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
+ ssh2_pkt_adduint32(mainchan->remoteid);
+ ssh2_pkt_addstring("x11-req");
+ ssh2_pkt_addbool(1); /* want reply */
+ ssh2_pkt_addbool(0); /* many connections */
+ ssh2_pkt_addstring(proto);
+ ssh2_pkt_addstring(data);
+ ssh2_pkt_adduint32(0); /* screen number */
+ ssh2_pkt_send();
+
+ do {
+ crWaitUntilV(ispkt);
+ if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue; /* nonexistent channel */
+ c->v2.remwindow += ssh2_pkt_getuint32();
+ }
+ } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+
+ if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
+ if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
+ bombout(("Server got confused by X11 forwarding request"));
+ crReturnV;
+ }
+ logevent("X11 forwarding refused");
+ } else {
+ logevent("X11 forwarding enabled");
+ ssh_X11_fwd_enabled = TRUE;
+ }
+ }
+
+ /*
+ * Now allocate a pty for the session.
+ */
+ if (!cfg.nopty) {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
+ ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
+ ssh2_pkt_addstring("pty-req");
+ ssh2_pkt_addbool(1); /* want reply */
+ ssh2_pkt_addstring(cfg.termtype);
+ ssh2_pkt_adduint32(cols);
+ ssh2_pkt_adduint32(rows);
+ ssh2_pkt_adduint32(0); /* pixel width */
+ ssh2_pkt_adduint32(0); /* pixel height */
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_addstring_data("\0", 1);/* TTY_OP_END, no special options */
+ ssh2_pkt_send();
+ ssh_state = SSH_STATE_INTERMED;
+
+ do {
+ crWaitUntilV(ispkt);
+ if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue; /* nonexistent channel */
+ c->v2.remwindow += ssh2_pkt_getuint32();
+ }
+ } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+
+ if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
+ if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
+ bombout(("Server got confused by pty request"));
+ crReturnV;
+ }
+ c_write("Server refused to allocate pty\r\n", 32);
+ ssh_editing = ssh_echoing = 1;
+ } else {
+ logevent("Allocated pty");
+ }
+ } else {
+ ssh_editing = ssh_echoing = 1;
+ }
+
+ /*
+ * Start a shell or a remote command.
+ */
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
+ ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
+ if (*cfg.remote_cmd) {
+ ssh2_pkt_addstring("exec");
+ ssh2_pkt_addbool(1); /* want reply */
+ ssh2_pkt_addstring(cfg.remote_cmd);
+ } else {
+ ssh2_pkt_addstring("shell");
+ ssh2_pkt_addbool(1); /* want reply */
+ }
+ ssh2_pkt_send();
+ do {
+ crWaitUntilV(ispkt);
+ if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue; /* nonexistent channel */
+ c->v2.remwindow += ssh2_pkt_getuint32();
+ }
+ } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+ if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
+ if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
+ bombout(("Server got confused by shell/command request"));
+ crReturnV;
+ }
+ bombout(("Server refused to start a shell/command"));
+ crReturnV;
+ } else {
+ logevent("Started a shell/command");
+ }
ssh_state = SSH_STATE_SESSION;
if (size_needed)
ssh_size();
+ if (eof_needed)
+ ssh_special(TS_EOF);
+ /*
+ * Transfer data!
+ */
+ ldisc_send(NULL, 0); /* cause ldisc to notice changes */
+ ssh_send_ok = 1;
while (1) {
+ static int try_send;
crReturnV;
+ try_send = FALSE;
if (ispkt) {
- if (pktin.type == 17 || pktin.type == 18) {
- long len = 0;
- for (i = 0; i < 4; i++)
- len = (len << 8) + pktin.body[i];
- c_write(pktin.body+4, len);
- } else if (pktin.type == 1) {
- /* SSH_MSG_DISCONNECT: do nothing */
- } else if (pktin.type == 14) {
- /* SSH_MSG_SUCCESS: may be from EXEC_SHELL on some servers */
- } else if (pktin.type == 15) {
- /* SSH_MSG_FAILURE: may be from EXEC_SHELL on some servers
- * if no pty is available or in other odd cases. Ignore */
- } else if (pktin.type == 20) {
- /* EXITSTATUS */
- s_wrpkt_start(33, 0);
- s_wrpkt();
+ if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
+ pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
+ char *data;
+ int length;
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue; /* nonexistent channel */
+ if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
+ ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
+ continue; /* extended but not stderr */
+ ssh2_pkt_getstring(&data, &length);
+ if (data) {
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ from_backend(pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA,
+ data, length);
+ break;
+ case CHAN_X11:
+ x11_send(c->u.x11.s, data, length);
+ break;
+ }
+ /*
+ * Enlarge the window again at the remote
+ * side, just in case it ever runs down and
+ * they fail to send us any more data.
+ */
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_adduint32(length);
+ ssh2_pkt_send();
+ }
+ } else if (pktin.type == SSH2_MSG_DISCONNECT) {
+ ssh_state = SSH_STATE_CLOSED;
+ logevent("Received disconnect message");
+ crReturnV;
+ } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
+ continue; /* exit status et al; ignore (FIXME?) */
+ } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue; /* nonexistent channel */
+
+ if (c->type == CHAN_X11) {
+ /*
+ * Remote EOF on an X11 channel means we should
+ * wrap up and close the channel ourselves.
+ */
+ x11_close(c->u.x11.s);
+ sshfwd_close(c);
+ }
+ } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+ enum234 e;
+
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue; /* nonexistent channel */
+ if (c->closes == 0) {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_send();
+ }
+ /* Do pre-close processing on the channel. */
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ break; /* nothing to see here, move along */
+ case CHAN_X11:
+ break;
+ }
+ del234(ssh_channels, c);
+ sfree(c->v2.outbuffer);
+ sfree(c);
+
+ /*
+ * See if that was the last channel left open.
+ */
+ c = first234(ssh_channels, &e);
+ if (!c) {
+ logevent("All channels closed. Disconnecting");
+ ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
+ ssh2_pkt_addstring("All open channels closed");
+ ssh2_pkt_addstring("en"); /* language tag */
+ ssh2_pkt_send();
+ ssh_state = SSH_STATE_CLOSED;
+ crReturnV;
+ }
+ continue; /* remote sends close; ignore (FIXME) */
+ } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue; /* nonexistent channel */
+ mainchan->v2.remwindow += ssh2_pkt_getuint32();
+ try_send = TRUE;
+ } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) {
+ char *type;
+ int typelen;
+ char *error = NULL;
+ struct ssh_channel *c;
+ ssh2_pkt_getstring(&type, &typelen);
+ c = smalloc(sizeof(struct ssh_channel));
+
+ if (typelen == 3 && !memcmp(type, "x11", 3)) {
+ if (!ssh_X11_fwd_enabled)
+ error = "X11 forwarding is not enabled";
+ else if ( x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL ) {
+ error = "Unable to open an X11 connection";
+ } else {
+ c->type = CHAN_X11;
+ }
+ } else {
+ error = "Unsupported channel type requested";
+ }
+
+ c->remoteid = ssh2_pkt_getuint32();
+ if (error) {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED);
+ ssh2_pkt_addstring(error);
+ ssh2_pkt_addstring("en"); /* language tag */
+ ssh2_pkt_send();
+ sfree(c);
+ } else {
+ struct ssh_channel *d;
+ unsigned i;
+ enum234 e;
+
+ for (i=1, d = first234(ssh_channels, &e); d;
+ d = next234(&e)) {
+ if (d->localid > i)
+ break; /* found a free number */
+ i = d->localid + 1;
+ }
+ c->localid = i;
+ c->closes = 0;
+ c->v2.remwindow = ssh2_pkt_getuint32();
+ c->v2.remmaxpkt = ssh2_pkt_getuint32();
+ c->v2.outbuffer = NULL;
+ c->v2.outbuflen = c->v2.outbufsize = 0;
+ add234(ssh_channels, c);
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_adduint32(c->localid);
+ ssh2_pkt_adduint32(0x8000UL); /* our window size */
+ ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
+ ssh2_pkt_send();
+ }
} else {
- fatalbox("Strange packet received: type %d", pktin.type);
+ bombout(("Strange packet received: type %d", pktin.type));
+ crReturnV;
}
} else {
- s_wrpkt_start(16, 4+inlen);
- pktout.body[0] = (inlen >> 24) & 0xFF;
- pktout.body[1] = (inlen >> 16) & 0xFF;
- pktout.body[2] = (inlen >> 8) & 0xFF;
- pktout.body[3] = inlen & 0xFF;
- memcpy(pktout.body+4, in, inlen);
- s_wrpkt();
+ /*
+ * We have spare data. Add it to the channel buffer.
+ */
+ ssh2_add_channel_data(mainchan, in, inlen);
+ try_send = TRUE;
}
+ if (try_send) {
+ enum234 e;
+ struct ssh_channel *c;
+ /*
+ * Try to send data on all channels if we can.
+ */
+ for (c = first234(ssh_channels, &e); c; c = next234(&e))
+ ssh2_try_send(c);
+ }
}
crFinishV;
}
/*
- * Called to set up the connection. Will arrange for WM_NETEVENT
- * messages to be passed to the specified window, whose window
- * procedure should then call telnet_msg().
+ * Handle the top-level SSH2 protocol.
+ */
+static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
+{
+ if (do_ssh2_transport(in, inlen, ispkt) == 0)
+ return;
+ do_ssh2_authconn(in, inlen, ispkt);
+}
+
+/*
+ * Called to set up the connection.
*
* Returns an error message, or NULL on success.
- *
- * Also places the canonical host name into `realhost'.
*/
-static char *ssh_init (HWND hwnd, char *host, int port, char **realhost) {
- SOCKADDR_IN addr;
- struct hostent *h;
- unsigned long a;
-#ifdef FWHACK
- char *FWhost;
- int FWport;
-#endif
-
- savedhost = malloc(1+strlen(host));
- if (!savedhost)
- fatalbox("Out of memory");
- strcpy(savedhost, host);
-
-#ifdef FWHACK
- FWhost = host;
- FWport = port;
- host = FWSTR;
- port = 23;
-#endif
-
- /*
- * Try to find host.
- */
- if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
- if ( (h = gethostbyname(host)) == NULL)
- switch (WSAGetLastError()) {
- case WSAENETDOWN: return "Network is down";
- case WSAHOST_NOT_FOUND: case WSANO_DATA:
- return "Host does not exist";
- case WSATRY_AGAIN: return "Host not found";
- default: return "gethostbyname: unknown error";
- }
- memcpy (&a, h->h_addr, sizeof(a));
- *realhost = h->h_name;
- } else
- *realhost = host;
-#ifdef FWHACK
- *realhost = FWhost;
-#endif
- a = ntohl(a);
-
- if (port < 0)
- port = 22; /* default ssh port */
-
- /*
- * Open socket.
- */
- s = socket(AF_INET, SOCK_STREAM, 0);
- if (s == INVALID_SOCKET)
- switch (WSAGetLastError()) {
- case WSAENETDOWN: return "Network is down";
- case WSAEAFNOSUPPORT: return "TCP/IP support not present";
- default: return "socket(): unknown error";
- }
-
- /*
- * Bind to local address.
- */
- addr.sin_family = AF_INET;
- addr.sin_addr.s_addr = htonl(INADDR_ANY);
- addr.sin_port = htons(0);
- if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
- switch (WSAGetLastError()) {
- case WSAENETDOWN: return "Network is down";
- default: return "bind(): unknown error";
- }
-
- /*
- * Connect to remote address.
- */
- addr.sin_addr.s_addr = htonl(a);
- addr.sin_port = htons((short)port);
- if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
- switch (WSAGetLastError()) {
- case WSAENETDOWN: return "Network is down";
- case WSAECONNREFUSED: return "Connection refused";
- case WSAENETUNREACH: return "Network is unreachable";
- case WSAEHOSTUNREACH: return "No route to host";
- default: return "connect(): unknown error";
- }
-
-#ifdef FWHACK
- send(s, "connect ", 8, 0);
- send(s, FWhost, strlen(FWhost), 0);
- {
- char buf[20];
- sprintf(buf, " %d\n", FWport);
- send (s, buf, strlen(buf), 0);
- }
+static char *ssh_init (char *host, int port, char **realhost) {
+ char *p;
+
+#ifdef MSCRYPTOAPI
+ if(crypto_startup() == 0)
+ return "Microsoft high encryption pack not installed!";
#endif
- if (!do_ssh_init())
- return "Protocol initialisation error";
+ ssh_send_ok = 0;
+ ssh_editing = 0;
+ ssh_echoing = 0;
- if (WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR)
- switch (WSAGetLastError()) {
- case WSAENETDOWN: return "Network is down";
- default: return "WSAAsyncSelect(): unknown error";
- }
+ p = connect_to_host(host, port, realhost);
+ if (p != NULL)
+ return p;
return NULL;
}
-/*
- * Process a WM_NETEVENT message. Will return 0 if the connection
- * has closed, or <0 for a socket error.
- */
-static int ssh_msg (WPARAM wParam, LPARAM lParam) {
- int ret;
- char buf[256];
-
- if (s == INVALID_SOCKET) /* how the hell did we get here?! */
- return -5000;
-
- if (WSAGETSELECTERROR(lParam) != 0)
- return -WSAGETSELECTERROR(lParam);
-
- switch (WSAGETSELECTEVENT(lParam)) {
- case FD_READ:
- ret = recv(s, buf, sizeof(buf), 0);
- if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
- return 1;
- if (ret < 0) /* any _other_ error */
- return -10000-WSAGetLastError();
- if (ret == 0) {
- s = INVALID_SOCKET;
- return 0; /* can't happen, in theory */
- }
- ssh_gotdata (buf, ret);
- return 1;
- case FD_CLOSE:
- s = INVALID_SOCKET;
- return 0;
- }
- return 1; /* shouldn't happen, but WTF */
-}
-
/*
* Called to send data down the Telnet connection.
*/
static void ssh_send (char *buf, int len) {
- if (s == INVALID_SOCKET)
+ if (s == NULL || ssh_protocol == NULL)
return;
ssh_protocol(buf, len, 0);
}
/*
- * Called to set the size of the window from Telnet's POV.
+ * Called to set the size of the window from SSH's POV.
*/
static void ssh_size(void) {
switch (ssh_state) {
case SSH_STATE_BEFORE_SIZE:
+ case SSH_STATE_PREPACKET:
+ case SSH_STATE_CLOSED:
break; /* do nothing */
case SSH_STATE_INTERMED:
size_needed = TRUE; /* buffer for later */
break;
case SSH_STATE_SESSION:
- s_wrpkt_start(11, 16);
- pktout.body[0] = (rows >> 24) & 0xFF;
- pktout.body[1] = (rows >> 16) & 0xFF;
- pktout.body[2] = (rows >> 8) & 0xFF;
- pktout.body[3] = rows & 0xFF;
- pktout.body[4] = (cols >> 24) & 0xFF;
- pktout.body[5] = (cols >> 16) & 0xFF;
- pktout.body[6] = (cols >> 8) & 0xFF;
- pktout.body[7] = cols & 0xFF;
- memset(pktout.body+8, 0, 8);
- s_wrpkt();
+ if (!cfg.nopty) {
+ if (ssh_version == 1) {
+ send_packet(SSH1_CMSG_WINDOW_SIZE,
+ PKT_INT, rows, PKT_INT, cols,
+ PKT_INT, 0, PKT_INT, 0, PKT_END);
+ } else {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
+ ssh2_pkt_adduint32(mainchan->remoteid);
+ ssh2_pkt_addstring("window-change");
+ ssh2_pkt_addbool(0);
+ ssh2_pkt_adduint32(cols);
+ ssh2_pkt_adduint32(rows);
+ ssh2_pkt_adduint32(0);
+ ssh2_pkt_adduint32(0);
+ ssh2_pkt_send();
+ }
+ }
+ break;
}
}
/*
- * (Send Telnet special codes)
+ * Send Telnet special codes. TS_EOF is useful for `plink', so you
+ * can send an EOF and collect resulting output (e.g. `plink
+ * hostname sort').
*/
static void ssh_special (Telnet_Special code) {
- /* do nothing */
+ if (code == TS_EOF) {
+ if (ssh_state != SSH_STATE_SESSION) {
+ /*
+ * Buffer the EOF in case we are pre-SESSION, so we can
+ * send it as soon as we reach SESSION.
+ */
+ if (code == TS_EOF)
+ eof_needed = TRUE;
+ return;
+ }
+ if (ssh_version == 1) {
+ send_packet(SSH1_CMSG_EOF, PKT_END);
+ } else {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
+ ssh2_pkt_adduint32(mainchan->remoteid);
+ ssh2_pkt_send();
+ }
+ logevent("Sent EOF message");
+ } else if (code == TS_PING) {
+ if (ssh_state == SSH_STATE_CLOSED || ssh_state == SSH_STATE_PREPACKET)
+ return;
+ if (ssh_version == 1) {
+ send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
+ } else {
+ ssh2_pkt_init(SSH2_MSG_IGNORE);
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_send();
+ }
+ } else {
+ /* do nothing */
+ }
+}
+
+static Socket ssh_socket(void) { return s; }
+
+static int ssh_sendok(void) { return ssh_send_ok; }
+
+static int ssh_ldisc(int option) {
+ if (option == LD_ECHO) return ssh_echoing;
+ if (option == LD_EDIT) return ssh_editing;
+ return FALSE;
}
Backend ssh_backend = {
ssh_init,
- ssh_msg,
ssh_send,
ssh_size,
- ssh_special
+ ssh_special,
+ ssh_socket,
+ ssh_sendok,
+ ssh_ldisc,
+ 22
};