#include <stdio.h>
#include <stdlib.h>
+#include <stdarg.h>
+#include <assert.h>
#include <winsock.h>
#include "putty.h"
+#include "ssh.h"
+#include "scp.h"
#ifndef FALSE
#define FALSE 0
#define TRUE 1
#endif
-#include "ssh.h"
-
-#define SSH_MSG_DISCONNECT 1
-#define SSH_SMSG_PUBLIC_KEY 2
-#define SSH_CMSG_SESSION_KEY 3
-#define SSH_CMSG_USER 4
-#define SSH_CMSG_AUTH_PASSWORD 9
-#define SSH_CMSG_REQUEST_PTY 10
-#define SSH_CMSG_EXEC_SHELL 12
-#define SSH_CMSG_STDIN_DATA 16
-#define SSH_SMSG_STDOUT_DATA 17
-#define SSH_SMSG_STDERR_DATA 18
-#define SSH_SMSG_SUCCESS 14
-#define SSH_SMSG_FAILURE 15
-#define SSH_SMSG_EXITSTATUS 20
-#define SSH_MSG_IGNORE 32
-#define SSH_CMSG_EXIT_CONFIRMATION 33
-#define SSH_MSG_DEBUG 36
-#define SSH_CMSG_AUTH_TIS 39
-#define SSH_SMSG_AUTH_TIS_CHALLENGE 40
-#define SSH_CMSG_AUTH_TIS_RESPONSE 41
-
-#define SSH_AUTH_TIS 5
+#define logevent(s) { logevent(s); \
+ if (!(flags & FLAG_CONNECTION) && (flags & FLAG_VERBOSE)) \
+ fprintf(stderr, "%s\n", s); }
+
+#define SSH1_MSG_DISCONNECT 1
+#define SSH1_SMSG_PUBLIC_KEY 2
+#define SSH1_CMSG_SESSION_KEY 3
+#define SSH1_CMSG_USER 4
+#define SSH1_CMSG_AUTH_RSA 6
+#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7
+#define SSH1_CMSG_AUTH_RSA_RESPONSE 8
+#define SSH1_CMSG_AUTH_PASSWORD 9
+#define SSH1_CMSG_REQUEST_PTY 10
+#define SSH1_CMSG_WINDOW_SIZE 11
+#define SSH1_CMSG_EXEC_SHELL 12
+#define SSH1_CMSG_EXEC_CMD 13
+#define SSH1_SMSG_SUCCESS 14
+#define SSH1_SMSG_FAILURE 15
+#define SSH1_CMSG_STDIN_DATA 16
+#define SSH1_SMSG_STDOUT_DATA 17
+#define SSH1_SMSG_STDERR_DATA 18
+#define SSH1_CMSG_EOF 19
+#define SSH1_SMSG_EXIT_STATUS 20
+#define SSH1_CMSG_EXIT_CONFIRMATION 33
+#define SSH1_MSG_IGNORE 32
+#define SSH1_MSG_DEBUG 36
+#define SSH1_CMSG_AUTH_TIS 39
+#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40
+#define SSH1_CMSG_AUTH_TIS_RESPONSE 41
+
+#define SSH1_AUTH_TIS 5
+
+#define SSH2_MSG_DISCONNECT 1
+#define SSH2_MSG_IGNORE 2
+#define SSH2_MSG_UNIMPLEMENTED 3
+#define SSH2_MSG_DEBUG 4
+#define SSH2_MSG_SERVICE_REQUEST 5
+#define SSH2_MSG_SERVICE_ACCEPT 6
+#define SSH2_MSG_KEXINIT 20
+#define SSH2_MSG_NEWKEYS 21
+#define SSH2_MSG_KEXDH_INIT 30
+#define SSH2_MSG_KEXDH_REPLY 31
+#define SSH2_MSG_USERAUTH_REQUEST 50
+#define SSH2_MSG_USERAUTH_FAILURE 51
+#define SSH2_MSG_USERAUTH_SUCCESS 52
+#define SSH2_MSG_USERAUTH_BANNER 53
+#define SSH2_MSG_USERAUTH_PK_OK 60
+#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60
+#define SSH2_MSG_GLOBAL_REQUEST 80
+#define SSH2_MSG_REQUEST_SUCCESS 81
+#define SSH2_MSG_REQUEST_FAILURE 82
+#define SSH2_MSG_CHANNEL_OPEN 90
+#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91
+#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92
+#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93
+#define SSH2_MSG_CHANNEL_DATA 94
+#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95
+#define SSH2_MSG_CHANNEL_EOF 96
+#define SSH2_MSG_CHANNEL_CLOSE 97
+#define SSH2_MSG_CHANNEL_REQUEST 98
+#define SSH2_MSG_CHANNEL_SUCCESS 99
+#define SSH2_MSG_CHANNEL_FAILURE 100
+
+#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1
+#define SSH2_OPEN_CONNECT_FAILED 2
+#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3
+#define SSH2_OPEN_RESOURCE_SHORTAGE 4
+#define SSH2_EXTENDED_DATA_STDERR 1
+
+#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 struct ssh_cipher ssh_3des;
+extern struct ssh_cipher ssh_3des_ssh2;
+extern struct ssh_cipher ssh_des;
+extern struct ssh_cipher ssh_blowfish;
+
+/* for ssh 2; we miss out single-DES because it isn't supported */
+struct ssh_cipher *ciphers[] = { &ssh_3des_ssh2, &ssh_blowfish };
+
+extern struct ssh_kex ssh_diffiehellman;
+struct ssh_kex *kex_algs[] = { &ssh_diffiehellman };
+
+extern struct ssh_hostkey ssh_dss;
+struct ssh_hostkey *hostkey_algs[] = { &ssh_dss };
+
+extern struct ssh_mac ssh_sha1;
+
+SHA_State exhash;
+
+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; }
+struct ssh_mac ssh_mac_none = {
+ nullmac_key, nullmac_key, nullmac_generate, nullmac_verify, "none", 0
+};
+struct ssh_mac *macs[] = { &ssh_sha1, &ssh_mac_none };
+
+struct ssh_compress ssh_comp_none = {
+ "none"
+};
+struct ssh_compress *compressions[] = { &ssh_comp_none };
static SOCKET s = INVALID_SOCKET;
static unsigned char session_key[32];
static struct ssh_cipher *cipher = NULL;
+static struct ssh_cipher *cscipher = NULL;
+static struct ssh_cipher *sccipher = NULL;
+static struct ssh_mac *csmac = NULL;
+static struct ssh_mac *scmac = NULL;
+static struct ssh_compress *cscomp = NULL;
+static struct ssh_compress *sccomp = NULL;
+static struct ssh_kex *kex = NULL;
+static struct ssh_hostkey *hostkey = NULL;
+int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
static char *savedhost;
static void s_write (char *buf, int len) {
while (len > 0) {
int i = send (s, buf, len, 0);
+ noise_ultralight(i);
+ if (i <= 0)
+ fatalbox("Lost connection while sending");
if (i > 0)
len -= i, buf += i;
}
int ret = 0;
while (len > 0) {
int i = recv (s, buf, len, 0);
+ noise_ultralight(i);
if (i > 0)
len -= i, buf += i, ret += i;
else
}
static void c_write (char *buf, int len) {
- while (len--) {
- int new_head = (inbuf_head + 1) & INBUF_MASK;
- if (new_head != inbuf_reap) {
- inbuf[inbuf_head] = *buf++;
- inbuf_head = new_head;
- }
+ if (!(flags & FLAG_CONNECTION)) {
+ int i;
+ for (i = 0; i < len; i++)
+ if (buf[i] != '\r')
+ fputc(buf[i], stderr);
+ return;
}
+ while (len--)
+ c_write1(*buf++);
}
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 struct Packet pktin = { 0, 0, NULL, NULL, 0 };
+static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
-static void ssh_protocol(unsigned char *in, int inlen, int ispkt);
+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_gotdata(unsigned char *data, int datalen) {
- static long len, biglen, to_read;
+static int (*s_rdpkt)(unsigned char **data, int *datalen);
+
+/*
+ * 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)
+{
+ static long len, pad, biglen, to_read;
+ static unsigned long realcrc, gotcrc;
static unsigned char *p;
- static int i, pad;
+ static int i;
crBegin;
- while (1) {
- for (i = len = 0; i < 4; i++) {
- while (datalen == 0)
- crReturnV;
- len = (len << 8) + *data;
- data++, datalen--;
- }
+
+next_packet:
+
+ pktin.type = 0;
+ pktin.length = 0;
+
+ for (i = len = 0; i < 4; i++) {
+ while ((*datalen) == 0)
+ crReturn(4-i);
+ len = (len << 8) + **data;
+ (*data)++, (*datalen)--;
+ }
#ifdef FWHACK
- if (len == 0x52656d6f) { /* "Remo"te server has closed ... */
- len = 0x300; /* big enough to carry to end */
- }
+ if (len == 0x52656d6f) { /* "Remo"te server has closed ... */
+ len = 0x300; /* big enough to carry to end */
+ }
#endif
- pad = 8 - (len%8);
+ pad = 8 - (len % 8);
+ biglen = len + pad;
+ pktin.length = len - 5;
- biglen = len + pad;
+ if (pktin.maxlen < biglen) {
+ pktin.maxlen = biglen;
+ pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) :
+ realloc(pktin.data, biglen+APIEXTRA));
+ if (!pktin.data)
+ fatalbox("Out of memory");
+ }
- len -= 5; /* type and CRC */
+ to_read = biglen;
+ p = pktin.data;
+ while (to_read > 0) {
+ static int chunk;
+ chunk = to_read;
+ while ((*datalen) == 0)
+ crReturn(to_read);
+ if (chunk > (*datalen))
+ chunk = (*datalen);
+ memcpy(p, *data, chunk);
+ *data += chunk;
+ *datalen -= chunk;
+ p += chunk;
+ to_read -= chunk;
+ }
- pktin.length = len;
- if (pktin.maxlen < biglen) {
- pktin.maxlen = biglen;
- pktin.data = (pktin.data == NULL ? malloc(biglen) :
- realloc(pktin.data, biglen));
- if (!pktin.data)
- fatalbox("Out of memory");
- }
+ if (cipher)
+ cipher->decrypt(pktin.data, biglen);
- 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;
- }
+ pktin.type = pktin.data[pad];
+ pktin.body = pktin.data + pad + 1;
+
+ realcrc = crc32(pktin.data, biglen-4);
+ gotcrc = GET_32BIT(pktin.data+biglen-4);
+ if (gotcrc != realcrc) {
+ fatalbox("Incorrect CRC received on packet");
+ }
+
+ 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) {
+ long strlen = GET_32BIT(pktin.body);
+ if (strlen + 4 != pktin.length)
+ fatalbox("Received data packet with bogus string length");
+ }
+
+ 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;
+ }
+
+ crFinish(0);
+}
+
+static int ssh2_rdpkt(unsigned char **data, int *datalen)
+{
+ static long len, pad, payload, packetlen, maclen;
+ static int i;
+ static int cipherblk;
+ static unsigned long incoming_sequence = 0;
+
+ crBegin;
+
+next_packet:
+
+ pktin.type = 0;
+ pktin.length = 0;
+
+ if (cipher)
+ cipherblk = cipher->blksize;
+ else
+ cipherblk = 8;
+ if (cipherblk < 8)
+ cipherblk = 8;
+
+ if (pktin.maxlen < cipherblk) {
+ pktin.maxlen = cipherblk;
+ pktin.data = (pktin.data == NULL ? malloc(cipherblk+APIEXTRA) :
+ realloc(pktin.data, cipherblk+APIEXTRA));
+ if (!pktin.data)
+ fatalbox("Out of memory");
+ }
+
+ /*
+ * Acquire and decrypt the first block of the packet. This will
+ * contain the length and padding details.
+ */
+ for (i = len = 0; i < cipherblk; i++) {
+ while ((*datalen) == 0)
+ crReturn(cipherblk-i);
+ pktin.data[i] = *(*data)++;
+ (*datalen)--;
+ }
+#ifdef FWHACK
+ if (!memcmp(pktin.data, "Remo", 4)) {/* "Remo"te server has closed ... */
+ /* FIXME */
+ }
+#endif
+ if (sccipher)
+ sccipher->decrypt(pktin.data, cipherblk);
+
+ /*
+ * Now get the length and padding figures.
+ */
+ len = GET_32BIT(pktin.data);
+ pad = pktin.data[4];
+
+ /*
+ * This enables us to deduce the payload length.
+ */
+ payload = len - pad - 1;
- if (cipher)
- cipher->decrypt(pktin.data, biglen);
+ pktin.length = payload + 5;
- pktin.type = pktin.data[pad];
- pktin.body = pktin.data+pad+1;
+ /*
+ * So now we can work out the total packet length.
+ */
+ packetlen = len + 4;
+ maclen = scmac ? scmac->len : 0;
+
+ /*
+ * Adjust memory allocation if packet is too big.
+ */
+ if (pktin.maxlen < packetlen) {
+ pktin.maxlen = packetlen;
+ pktin.data = (pktin.data == NULL ? malloc(packetlen+APIEXTRA) :
+ realloc(pktin.data, packetlen+APIEXTRA));
+ if (!pktin.data)
+ fatalbox("Out of memory");
+ }
- if (pktin.type == SSH_MSG_DEBUG) {
- /* FIXME: log it */
- } else if (pktin.type == SSH_MSG_IGNORE) {
- /* do nothing */;
- } else
+ /*
+ * Read and decrypt the remainder of the packet.
+ */
+ for (i = cipherblk; i < packetlen + maclen; i++) {
+ while ((*datalen) == 0)
+ crReturn(packetlen + maclen - i);
+ pktin.data[i] = *(*data)++;
+ (*datalen)--;
+ }
+ /* Decrypt everything _except_ the MAC. */
+ if (sccipher)
+ sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk);
+
+#if 0
+ debug(("Got packet len=%d pad=%d\r\n", len, pad));
+ for (i = 0; i < packetlen; i++)
+ debug((" %02x", (unsigned char)pktin.data[i]));
+ debug(("\r\n"));
+#endif
+
+ /*
+ * Check the MAC.
+ */
+ if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence))
+ fatalbox("Incorrect MAC received on packet");
+ incoming_sequence++; /* whether or not we MACed */
+
+ 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 ssh_gotdata(unsigned char *data, int datalen)
+{
+ while (datalen > 0) {
+ if ( s_rdpkt(&data, &datalen) == 0 ) {
ssh_protocol(NULL, 0, 1);
+ if (ssh_state == SSH_STATE_CLOSED) {
+ return;
+ }
+ }
}
- crFinishV;
}
+
static void s_wrpkt_start(int type, int len) {
int pad, biglen;
pktout.length = len-5;
if (pktout.maxlen < biglen) {
pktout.maxlen = biglen;
+#ifdef MSCRYPTOAPI
+ /* Allocate enough buffer space for extra block
+ * for MS CryptEncrypt() */
+ pktout.data = (pktout.data == NULL ? malloc(biglen+12) :
+ realloc(pktout.data, biglen+12));
+#else
pktout.data = (pktout.data == NULL ? malloc(biglen+4) :
realloc(pktout.data, biglen+4));
+#endif
if (!pktout.data)
fatalbox("Out of memory");
}
for (i=0; i<pad; i++)
pktout.data[i+4] = random_byte();
crc = crc32(pktout.data+4, biglen-4);
-
- 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);
-
- pktout.data[0] = (len >> 24) & 0xFF;
- pktout.data[1] = (len >> 16) & 0xFF;
- pktout.data[2] = (len >> 8) & 0xFF;
- pktout.data[3] = len & 0xFF;
+ PUT_32BIT(pktout.data+biglen, crc);
+ PUT_32BIT(pktout.data, len);
if (cipher)
cipher->encrypt(pktout.data+4, biglen);
s_write(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;
+ int i;
+
+ 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);
+ i = 16 * bn[0] - 1;
+ while ( i > 0 && (bn[i/16+1] >> (i%16)) == 0 )
+ i--;
+ pktlen += 2 + (i+7)/8;
+ 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);
+ i = 16 * bn[0] - 1;
+ while ( i > 0 && (bn[i/16+1] >> (i%16)) == 0 )
+ i--;
+ *p++ = (i >> 8) & 0xFF;
+ *p++ = i & 0xFF;
+ i = (i + 7) / 8;
+ while (i-- > 0) {
+ if (i % 2)
+ *p++ = bn[i/2+1] >> 8;
+ else
+ *p++ = bn[i/2+1] & 0xFF;
+ }
+ break;
+ }
+ }
+ va_end(args);
+
+ s_wrpkt();
+}
+
+
+/*
+ * 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_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);
+
+ if (port < 0)
+ port = 22; /* default ssh port */
+
+#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);
+
+ /*
+ * 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);
+ }
+#endif
+
+ return NULL;
+}
+
static int ssh_versioncmp(char *a, char *b) {
char *ae, *be;
unsigned long av, bv;
return 0;
}
+
+/*
+ * Utility routine for putting an SSH-protocol `string' into a SHA
+ * state.
+ */
+#include <stdio.h>
+void sha_string(SHA_State *s, void *str, int len) {
+ unsigned char lenblk[4];
+static FILE *fp;
+ PUT_32BIT(lenblk, len);
+if (!fp) fp = fopen("h:\\statham\\windows\\putty\\data","wb");
+fwrite(lenblk, 4, 1, fp);
+ SHA_Bytes(s, lenblk, 4);
+fwrite(str, len, 1, fp);
+fflush(fp);
+ SHA_Bytes(s, str, len);
+}
+
+/*
+ * SSH2 packet construction functions.
+ */
+void ssh2_pkt_adddata(void *data, int len) {
+ pktout.length += len;
+ if (pktout.maxlen < pktout.length) {
+ pktout.maxlen = pktout.length + 256;
+ pktout.data = (pktout.data == NULL ? malloc(pktout.maxlen+APIEXTRA) :
+ realloc(pktout.data, pktout.maxlen+APIEXTRA));
+ if (!pktout.data)
+ fatalbox("Out of memory");
+ }
+ memcpy(pktout.data+pktout.length-len, data, len);
+}
+void ssh2_pkt_addbyte(unsigned char byte) {
+ ssh2_pkt_adddata(&byte, 1);
+}
+void ssh2_pkt_init(int pkt_type) {
+ pktout.length = 5;
+ ssh2_pkt_addbyte((unsigned char)pkt_type);
+}
+void ssh2_pkt_addbool(unsigned char value) {
+ ssh2_pkt_adddata(&value, 1);
+}
+void ssh2_pkt_adduint32(unsigned long value) {
+ unsigned char x[4];
+ PUT_32BIT(x, value);
+ ssh2_pkt_adddata(x, 4);
+}
+void ssh2_pkt_addstring_start(void) {
+ ssh2_pkt_adduint32(0);
+ pktout.savedpos = pktout.length;
+}
+void ssh2_pkt_addstring_str(char *data) {
+ ssh2_pkt_adddata(data, strlen(data));
+ PUT_32BIT(pktout.data + pktout.savedpos - 4,
+ pktout.length - pktout.savedpos);
+}
+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);
+}
+void ssh2_pkt_addstring(char *data) {
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_addstring_str(data);
+}
+char *ssh2_mpint_fmt(Bignum b, int *len) {
+ unsigned char *p;
+ int i, n = b[0];
+ p = malloc(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;
+}
+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);
+ free(p);
+}
+void ssh2_pkt_send(void) {
+ int cipherblk, maclen, padding, i;
+ static unsigned long outgoing_sequence = 0;
+
+ /*
+ * 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;
+ 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);
+ maclen = csmac ? csmac->len : 0;
+
+ s_write(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"));
+ free(p);
+}
+#endif
+
+void sha_mpint(SHA_State *s, Bignum b) {
+ unsigned char *p;
+ int len;
+ p = ssh2_mpint_fmt(b, &len);
+ sha_string(s, p, len);
+ free(p);
+}
+
+/*
+ * SSH2 packet decode functions.
+ */
+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;
+}
+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;
+}
+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)
+ fatalbox("internal error: Can't handle negative mpints");
+ 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]);
+ }
+ return b;
+}
+
static int do_ssh_init(void) {
- char c;
+ char c, *vsp;
char version[10];
- char vstring[40];
+ char vstring[80];
+ char vlog[sizeof(vstring)+20];
int i;
#ifdef FWHACK
if (s_read(&c,1) != 1 || c != 'S') return 0;
if (s_read(&c,1) != 1 || c != 'H') return 0;
#endif
+ strcpy(vstring, "SSH-");
+ vsp = vstring+4;
if (s_read(&c,1) != 1 || c != '-') return 0;
i = 0;
while (1) {
if (s_read(&c,1) != 1)
return 0;
+ if (vsp < vstring+sizeof(vstring)-1)
+ *vsp++ = c;
if (i >= 0) {
if (c == '-') {
version[i] = '\0';
break;
}
- sprintf(vstring, "SSH-%s-PuTTY\n",
- (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
- s_write(vstring, strlen(vstring));
+ *vsp = 0;
+ sprintf(vlog, "Server version: %s", vstring);
+ vlog[strcspn(vlog, "\r\n")] = '\0';
+ logevent(vlog);
+
+ if (ssh_versioncmp(version, "2.0" /* FIXME: "1.99" */ ) >= 0) {
+ /*
+ * This is a v2 server. Begin v2 protocol.
+ */
+ char *verstring = "SSH-2.0-PuTTY";
+ SHA_Init(&exhash);
+ /*
+ * Hash our version string and their version string.
+ */
+ sha_string(&exhash, verstring, strlen(verstring));
+ sha_string(&exhash, 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");
+ s_write(vstring, strlen(vstring));
+ ssh_protocol = ssh2_protocol;
+ 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");
+ s_write(vstring, strlen(vstring));
+ ssh_protocol = ssh1_protocol;
+ s_rdpkt = ssh1_rdpkt;
+ }
return 1;
}
-static void ssh_protocol(unsigned char *in, int inlen, int ispkt) {
+/*
+ * 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 session_id[16];
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;
- extern struct ssh_cipher ssh_3des;
- extern struct ssh_cipher ssh_des;
- extern struct ssh_cipher ssh_blowfish;
-
crBegin;
- random_init();
-
- while (!ispkt)
- crReturnV;
+ if (!ispkt) crWaitUntil(ispkt);
- if (pktin.type != SSH_SMSG_PUBLIC_KEY)
+ if (pktin.type != SSH1_SMSG_PUBLIC_KEY)
fatalbox("Public key packet not received");
- memcpy(cookie, pktin.body, 8);
-
- MD5Init(&md5c);
+ logevent("Received public keys");
- i = makekey(pktin.body+8, &servkey, &keystr1);
+ memcpy(cookie, pktin.body, 8);
- j = makekey(pktin.body+8+i, &hostkey, &keystr2);
+ i = makekey(pktin.body+8, &servkey, &keystr1, 0);
+ j = makekey(pktin.body+8+i, &hostkey, &keystr2, 0);
- supported_ciphers_mask = ((pktin.body[12+i+j] << 24) |
- (pktin.body[13+i+j] << 16) |
- (pktin.body[14+i+j] << 8) |
- (pktin.body[15+i+j]));
+ /*
+ * Hash the host key and print the hash in the log box. Just as
+ * a last resort in case the registry's host key checking is
+ * compromised, we'll allow the user some ability to verify
+ * host keys by eye.
+ */
+ MD5Init(&md5c);
+ MD5Update(&md5c, keystr2, hostkey.bytes);
+ MD5Final(session_id, &md5c);
+ {
+ char logmsg[80];
+ int i;
+ logevent("Host key MD5 is:");
+ strcpy(logmsg, " ");
+ for (i = 0; i < 16; i++)
+ sprintf(logmsg+strlen(logmsg), "%02x", session_id[i]);
+ logevent(logmsg);
+ }
- supported_auths_mask = ((pktin.body[16+i+j] << 24) |
- (pktin.body[17+i+j] << 16) |
- (pktin.body[18+i+j] << 8) |
- (pktin.body[19+i+j]));
+ 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);
for (i=0; i<32; i++)
if (!rsabuf)
fatalbox("Out of memory");
- verify_ssh_host_key(savedhost, &hostkey);
+ /*
+ * Verify the host key.
+ */
+ {
+ /*
+ * First format the key into a string.
+ */
+ int len = rsastr_len(&hostkey);
+ char *keystr = malloc(len);
+ if (!keystr)
+ fatalbox("Out of memory");
+ rsastr_fmt(keystr, &hostkey);
+ verify_ssh_host_key(savedhost, keystr);
+ free(keystr);
+ }
for (i=0; i<32; i++) {
rsabuf[i] = session_key[i];
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;
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...");
+
+ free(rsabuf);
+
+ cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish :
+ cipher_type == SSH_CIPHER_DES ? &ssh_des :
+ &ssh_3des;
+ cipher->sesskey(session_key);
+
+ crWaitUntil(ispkt);
+
+ if (pktin.type != SSH1_SMSG_SUCCESS)
+ fatalbox("Encryption not successfully enabled");
+
+ logevent("Successfully started encryption");
+
+ fflush(stdout);
+ {
+ static char username[100];
+ static int pos = 0;
+ static char c;
+ if (!(flags & FLAG_CONNECTION) && !*cfg.username) {
+ c_write("login as: ", 10);
+ 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 {
+ char stuff[200];
+ strncpy(username, cfg.username, 99);
+ username[99] = '\0';
+ if (flags & FLAG_VERBOSE) {
+ sprintf(stuff, "Sent username \"%s\".\r\n", username);
+ c_write(stuff, strlen(stuff));
+ }
+ }
+
+ send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
+ {
+ char userlog[20+sizeof(username)];
+ sprintf(userlog, "Sent username \"%s\"", username);
+ logevent(userlog);
+ }
+ }
+
+ crWaitUntil(ispkt);
+
+ tried_publickey = 0;
+
+ while (pktin.type == SSH1_SMSG_FAILURE) {
+ static char password[100];
+ static int pos;
+ static char c;
+ static int pwpkt_type;
+ /*
+ * Show password prompt, having first obtained it via a TIS
+ * exchange if we're doing TIS authentication.
+ */
+ pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
+ if (*cfg.keyfile && !tried_publickey)
+ pwpkt_type = SSH1_CMSG_AUTH_RSA;
+
+ if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD && !FLAG_WINDOWED) {
+ char prompt[200];
+ sprintf(prompt, "%s@%s's password: ", cfg.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;
+ crReturn(1);
+ }
+ } else {
+
+ 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");
+ 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");
+ c_write(pktin.body+4, challengelen);
+ }
+ }
+ if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD)
+ c_write("password: ", 10);
+ if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
+ if (flags & FLAG_VERBOSE)
+ c_write("Trying public key authentication.\r\n", 35);
+ if (!rsakey_encrypted(cfg.keyfile)) {
+ if (flags & FLAG_VERBOSE)
+ c_write("No passphrase required.\r\n", 25);
+ goto tryauth;
+ }
+ c_write("passphrase: ", 12);
+ }
+
+ pos = 0;
+ 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, 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) {
+ if (flags & FLAG_VERBOSE)
+ c_write("Server refused our public key.\r\n", 32);
+ continue; /* go and try password */
+ }
+ if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE)
+ fatalbox("Bizarre response to offer of public key");
+ 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) {
+ fatalbox("Bizarre response to RSA authentication response");
+ }
+
+ 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) {
+ fatalbox("Strange packet received, type %d", pktin.type);
+ }
+ }
+
+ logevent("Authentication successful");
+
+ crFinish(1);
+}
+
+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.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) {
+ fatalbox("Protocol confusion");
+ } else if (pktin.type == SSH1_SMSG_FAILURE) {
+ c_write("Server refused to allocate pty\r\n", 32);
+ }
+ logevent("Allocated pty");
+ }
+
+ send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
+ logevent("Started session");
+
+ ssh_state = SSH_STATE_SESSION;
+ if (size_needed)
+ ssh_size();
+
+ while (1) {
+ crReturnV;
+ if (ispkt) {
+ if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
+ pktin.type == SSH1_SMSG_STDERR_DATA) {
+ long len = GET_32BIT(pktin.body);
+ c_write(pktin.body+4, len);
+ } else if (pktin.type == SSH1_MSG_DISCONNECT) {
+ ssh_state = SSH_STATE_CLOSED;
+ logevent("Received disconnect request");
+ } 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 {
+ fatalbox("Strange packet received: type %d", pktin.type);
+ }
+ } else {
+ send_packet(SSH1_CMSG_STDIN_DATA,
+ PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END);
+ }
+ }
+
+ crFinishV;
+}
+
+/*
+ * Utility routine for decoding comma-separated strings in KEXINIT.
+ */
+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.
+ */
+void ssh2_mkkey(Bignum K, char *H, 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, H, 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);
+}
+
+/*
+ * 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 struct ssh_cipher *cscipher_tobe = NULL;
+ static struct ssh_cipher *sccipher_tobe = NULL;
+ static struct ssh_mac *csmac_tobe = NULL;
+ static struct ssh_mac *scmac_tobe = NULL;
+ static struct ssh_compress *cscomp_tobe = NULL;
+ static struct ssh_compress *sccomp_tobe = NULL;
+ static char *hostkeydata, *sigdata, *keystr;
+ static int hostkeylen, siglen;
+ static unsigned char exchange_hash[20];
+ static unsigned char keyspace[40];
+
+ crBegin;
+ random_init();
+
+ 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); i++) {
+ ssh2_pkt_addstring_str(ciphers[i]->name);
+ if (i < lenof(ciphers)-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List server->client encryption algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(ciphers); i++) {
+ ssh2_pkt_addstring_str(ciphers[i]->name);
+ if (i < lenof(ciphers)-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List client->server MAC algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(macs); i++) {
+ ssh2_pkt_addstring_str(macs[i]->name);
+ if (i < lenof(macs)-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List server->client MAC algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(macs); i++) {
+ ssh2_pkt_addstring_str(macs[i]->name);
+ if (i < lenof(macs)-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List client->server compression algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(compressions); i++) {
+ ssh2_pkt_addstring_str(compressions[i]->name);
+ if (i < lenof(compressions)-1)
+ ssh2_pkt_addstring_str(",");
+ }
+ /* List server->client compression algorithms. */
+ ssh2_pkt_addstring_start();
+ for (i = 0; i < lenof(compressions); i++) {
+ ssh2_pkt_addstring_str(compressions[i]->name);
+ if (i < lenof(compressions)-1)
+ 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);
+ sha_string(&exhash, pktout.data+5, pktout.length-5);
+ ssh2_pkt_send();
+
+ if (!ispkt) crWaitUntil(ispkt);
+ sha_string(&exhash, pktin.data+5, pktin.length-5);
+
+ /*
+ * Now examine the other side's KEXINIT to see what we're up
+ * to.
+ */
+ if (pktin.type != SSH2_MSG_KEXINIT) {
+ fatalbox("expected key exchange packet from server");
+ }
+ 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); i++) {
+ if (in_commasep_string(ciphers[i]->name, str, len)) {
+ cscipher_tobe = ciphers[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* server->client cipher */
+ for (i = 0; i < lenof(ciphers); i++) {
+ if (in_commasep_string(ciphers[i]->name, str, len)) {
+ sccipher_tobe = ciphers[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* client->server mac */
+ for (i = 0; i < lenof(macs); i++) {
+ if (in_commasep_string(macs[i]->name, str, len)) {
+ csmac_tobe = macs[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* server->client mac */
+ for (i = 0; i < lenof(macs); i++) {
+ if (in_commasep_string(macs[i]->name, str, len)) {
+ scmac_tobe = macs[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* client->server compression */
+ for (i = 0; i < lenof(compressions); i++) {
+ if (in_commasep_string(compressions[i]->name, str, len)) {
+ cscomp_tobe = compressions[i];
+ break;
+ }
+ }
+ ssh2_pkt_getstring(&str, &len); /* server->client compression */
+ for (i = 0; i < lenof(compressions); i++) {
+ if (in_commasep_string(compressions[i]->name, str, len)) {
+ sccomp_tobe = compressions[i];
+ break;
+ }
+ }
+
+ /*
+ * 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)
+ fatalbox("internal fault: chaos in SSH 2 transport layer");
+
+ /*
+ * 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) {
+ fatalbox("expected key exchange packet from server");
+ }
+ 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
- s_wrpkt_start(SSH_CMSG_SESSION_KEY, len+15);
- pktout.body[0] = cipher_type;
- 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();
+ hostkey->setkey(hostkeydata, hostkeylen);
+ if (!hostkey->verifysig(sigdata, siglen, exchange_hash, 20))
+ fatalbox("Server failed host key check");
- free(rsabuf);
+ /*
+ * Expect SSH2_MSG_NEWKEYS from server.
+ */
+ crWaitUntil(ispkt);
+ if (pktin.type != SSH2_MSG_NEWKEYS)
+ fatalbox("expected new-keys packet from server");
- cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish :
- cipher_type == SSH_CIPHER_DES ? &ssh_des :
- &ssh_3des;
- cipher->sesskey(session_key);
+ /*
+ * Authenticate remote host: verify host key. (We've already
+ * checked the signature of the exchange hash.)
+ */
+ keystr = hostkey->fmtkey();
+ verify_ssh_host_key(savedhost, keystr);
+ free(keystr);
- do { crReturnV; } while (!ispkt);
+ /*
+ * Send SSH2_MSG_NEWKEYS.
+ */
+ ssh2_pkt_init(SSH2_MSG_NEWKEYS);
+ ssh2_pkt_send();
- if (pktin.type != SSH_SMSG_SUCCESS)
- fatalbox("Encryption not successfully enabled");
+ /*
+ * Create and initialise session keys.
+ */
+ cscipher = cscipher_tobe;
+ sccipher = sccipher_tobe;
+ csmac = csmac_tobe;
+ scmac = scmac_tobe;
+ cscomp = cscomp_tobe;
+ sccomp = sccomp_tobe;
+ /*
+ * Set IVs after keys.
+ */
+ ssh2_mkkey(K, exchange_hash, 'C', keyspace); cscipher->setcskey(keyspace);
+ ssh2_mkkey(K, exchange_hash, 'D', keyspace); cscipher->setsckey(keyspace);
+ ssh2_mkkey(K, exchange_hash, 'A', keyspace); cscipher->setcsiv(keyspace);
+ ssh2_mkkey(K, exchange_hash, 'B', keyspace); sccipher->setsciv(keyspace);
+ ssh2_mkkey(K, exchange_hash, 'E', keyspace); csmac->setcskey(keyspace);
+ ssh2_mkkey(K, exchange_hash, 'F', keyspace); scmac->setsckey(keyspace);
- fflush(stdout);
- {
+ /*
+ * 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.
+ */
+ do {
+ crReturn(1);
+ } while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT));
+ goto begin_key_exchange;
+
+ crFinish(1);
+}
+
+/*
+ * Handle the SSH2 userauth and connection layers.
+ */
+static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
+{
+ static unsigned long their_channel;
+ static unsigned long remote_winsize;
+ static unsigned long remote_maxpkt;
+
+ crBegin;
+
+ /*
+ * 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)
+ fatalbox("Server refused user authentication protocol");
+
+ /*
+ * 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_CONNECTION) && !*cfg.username) {
c_write("login as: ", 10);
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) {
+ sprintf(stuff, "Using username \"%s\".\r\n", username);
+ c_write(stuff, strlen(stuff));
+ }
}
- s_wrpkt_start(SSH_CMSG_USER, 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 == SSH_SMSG_FAILURE) {
- static char password[100];
- static int pos;
- static char c;
- static int pwpkt_type;
- /*
- * Show password prompt, having first obtained it via a TIS
- * exchange if we're doing TIS authentication.
- */
- pwpkt_type = SSH_CMSG_AUTH_PASSWORD;
- if (pktin.type == SSH_SMSG_FAILURE &&
- cfg.try_tis_auth &&
- (supported_auths_mask & (1<<SSH_AUTH_TIS))) {
- pwpkt_type = SSH_CMSG_AUTH_TIS_RESPONSE;
- s_wrpkt_start(SSH_CMSG_AUTH_TIS, 0);
- s_wrpkt();
- do { crReturnV; } while (!ispkt);
- if (pktin.type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
- 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]));
- c_write(pktin.body+4, challengelen);
+ if (!(flags & FLAG_WINDOWED)) {
+ char prompt[200];
+ sprintf(prompt, "%s@%s's password: ", cfg.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;
}
- }
- if (pwpkt_type == SSH_CMSG_AUTH_PASSWORD)
+ } else {
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;
- }
+ 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(pwpkt_type, 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;
}
- if (!cfg.nopty) {
- i = strlen(cfg.termtype);
- s_wrpkt_start(SSH_CMSG_REQUEST_PTY, 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 != SSH_SMSG_SUCCESS && pktin.type != SSH_SMSG_FAILURE) {
- fatalbox("Protocol confusion");
- } else if (pktin.type == SSH_SMSG_FAILURE) {
- 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.
+ */
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
+ ssh2_pkt_addstring("session");
+ ssh2_pkt_adduint32(100); /* as good as any */
+ ssh2_pkt_adduint32(0xFFFFFFFFUL); /* very big window which we ignore */
+ ssh2_pkt_adduint32(0xFFFFFFFFUL); /* very big max pkt size */
+ ssh2_pkt_send();
+ crWaitUntilV(ispkt);
+ if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
+ fatalbox("Server refused to open a session");
+ /* FIXME: error data comes back in FAILURE packet */
+ }
+ if (ssh2_pkt_getuint32() != 100) {
+ fatalbox("Server's channel confirmation cited wrong channel");
}
+ their_channel = ssh2_pkt_getuint32();
+ remote_winsize = ssh2_pkt_getuint32();
+ remote_maxpkt = ssh2_pkt_getuint32();
+ logevent("Opened channel for session");
- s_wrpkt_start(SSH_CMSG_EXEC_SHELL, 0);
- s_wrpkt();
+ /*
+ * Now allocate a pty for the session.
+ */
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
+ ssh2_pkt_adduint32(their_channel); /* 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();
+
+ do { /* FIXME: pay attention to these */
+ crWaitUntilV(ispkt);
+ } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+
+ if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
+ if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
+ fatalbox("Server got confused by pty request");
+ }
+ c_write("Server refused to allocate pty\r\n", 32);
+ } else {
+ logevent("Allocated pty");
+ }
- ssh_state = SSH_STATE_SESSION;
- if (size_needed)
- ssh_size();
+ /*
+ * Start a shell.
+ */
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
+ ssh2_pkt_adduint32(their_channel); /* recipient channel */
+ ssh2_pkt_addstring("shell");
+ ssh2_pkt_addbool(1); /* want reply */
+ ssh2_pkt_send();
+ do { /* FIXME: pay attention to these */
+ crWaitUntilV(ispkt);
+ } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+ if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
+ if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
+ fatalbox("Server got confused by shell request");
+ }
+ fatalbox("Server refused to start a shell");
+ } else {
+ logevent("Started a shell");
+ }
+ /*
+ * Transfer data!
+ */
while (1) {
crReturnV;
if (ispkt) {
- if (pktin.type == SSH_SMSG_STDOUT_DATA ||
- pktin.type == SSH_SMSG_STDERR_DATA) {
- 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 == SSH_MSG_DISCONNECT) {
+ if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
+ pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
+ char *data;
+ int length;
+ if (ssh2_pkt_getuint32() != 100)
+ continue; /* wrong 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)
+ c_write(data, length);
+ } else if (pktin.type == SSH2_MSG_DISCONNECT) {
ssh_state = SSH_STATE_CLOSED;
- } else if (pktin.type == SSH_SMSG_SUCCESS) {
- /* may be from EXEC_SHELL on some servers */
- } else if (pktin.type == SSH_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 == SSH_SMSG_EXITSTATUS) {
- s_wrpkt_start(SSH_CMSG_EXIT_CONFIRMATION, 0);
- s_wrpkt();
+ logevent("Received disconnect request");
+ } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
+ continue; /* exit status et al; ignore (FIXME?) */
+ } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
+ continue; /* ignore for now (FIXME!) */
} else {
fatalbox("Strange packet received: type %d", pktin.type);
}
} else {
- s_wrpkt_start(SSH_CMSG_STDIN_DATA, 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();
+ /* FIXME: for now, ignore window size */
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
+ ssh2_pkt_adduint32(their_channel);
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_addstring_data(in, inlen);
+ ssh2_pkt_send();
}
}
}
/*
+ * 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. Will arrange for WM_NETEVENT
* messages to be passed to the specified window, whose window
* procedure should then call telnet_msg().
*
* 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;
+ char *p;
+
+#ifdef MSCRYPTOAPI
+ if(crypto_startup() == 0)
+ return "Microsoft high encryption pack not installed!";
#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);
- }
-#endif
+ p = connect_to_host(host, port, realhost);
+ if (p != NULL)
+ return p;
if (!do_ssh_init())
return "Protocol initialisation error";
- if (WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR)
+ if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ | FD_CLOSE) == SOCKET_ERROR)
switch (WSAGetLastError()) {
case WSAENETDOWN: return "Network is down";
default: return "WSAAsyncSelect(): unknown error";
int ret;
char buf[256];
- if (s == INVALID_SOCKET) /* how the hell did we get here?! */
- return -5000;
+ /*
+ * Because reading less than the whole of the available pending
+ * data can generate an FD_READ event, we need to allow for the
+ * possibility that FD_READ may arrive with FD_CLOSE already in
+ * the queue; so it's possible that we can get here even with s
+ * invalid. If so, we return 1 and don't worry about it.
+ */
+ if (s == INVALID_SOCKET)
+ return 1;
if (WSAGETSELECTERROR(lParam) != 0)
return -WSAGETSELECTERROR(lParam);
switch (WSAGETSELECTEVENT(lParam)) {
case FD_READ:
+ case FD_CLOSE:
ret = recv(s, buf, sizeof(buf), 0);
if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
return 1;
return -10000-WSAGetLastError();
if (ret == 0) {
s = INVALID_SOCKET;
- return 0; /* can't happen, in theory */
+ return 0;
}
ssh_gotdata (buf, ret);
+ if (ssh_state == SSH_STATE_CLOSED) {
+ closesocket(s);
+ s = INVALID_SOCKET;
+ return 0;
+ }
return 1;
- case FD_CLOSE:
- s = INVALID_SOCKET;
- ssh_state = SSH_STATE_CLOSED;
- return 0;
}
return 1; /* shouldn't happen, but WTF */
}
break;
case SSH_STATE_SESSION:
if (!cfg.nopty) {
- 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();
+ send_packet(SSH1_CMSG_WINDOW_SIZE,
+ PKT_INT, rows, PKT_INT, cols,
+ PKT_INT, 0, PKT_INT, 0, PKT_END);
}
}
}
/* do nothing */
}
+
+/*
+ * Read and decrypt one incoming SSH packet.
+ * (only used by pSCP)
+ */
+static void get_packet(void)
+{
+ unsigned char buf[4096], *p;
+ long to_read;
+ int len;
+
+ p = NULL;
+ len = 0;
+
+ while ((to_read = s_rdpkt(&p, &len)) > 0) {
+ if (to_read > sizeof(buf)) to_read = sizeof(buf);
+ len = s_read(buf, to_read);
+ if (len != to_read) {
+ closesocket(s);
+ s = INVALID_SOCKET;
+ return;
+ }
+ p = buf;
+ }
+
+ assert(len == 0);
+}
+
+/*
+ * Receive a block of data over the SSH link. Block until
+ * all data is available. Return nr of bytes read (0 if lost connection).
+ * (only used by pSCP)
+ */
+int ssh_scp_recv(unsigned char *buf, int len)
+{
+ static int pending_input_len = 0;
+ static unsigned char *pending_input_ptr;
+ int to_read = len;
+
+ if (pending_input_len >= to_read) {
+ memcpy(buf, pending_input_ptr, to_read);
+ pending_input_ptr += to_read;
+ pending_input_len -= to_read;
+ return len;
+ }
+
+ if (pending_input_len > 0) {
+ memcpy(buf, pending_input_ptr, pending_input_len);
+ buf += pending_input_len;
+ to_read -= pending_input_len;
+ pending_input_len = 0;
+ }
+
+ if (s == INVALID_SOCKET)
+ return 0;
+ while (to_read > 0) {
+ get_packet();
+ if (s == INVALID_SOCKET)
+ return 0;
+ if (pktin.type == SSH1_SMSG_STDOUT_DATA) {
+ int plen = GET_32BIT(pktin.body);
+ if (plen <= to_read) {
+ memcpy(buf, pktin.body + 4, plen);
+ buf += plen;
+ to_read -= plen;
+ } else {
+ memcpy(buf, pktin.body + 4, to_read);
+ pending_input_len = plen - to_read;
+ pending_input_ptr = pktin.body + 4 + to_read;
+ to_read = 0;
+ }
+ } else if (pktin.type == SSH1_SMSG_STDERR_DATA) {
+ int plen = GET_32BIT(pktin.body);
+ fwrite(pktin.body + 4, plen, 1, stderr);
+ } else if (pktin.type == SSH1_MSG_DISCONNECT) {
+ logevent("Received disconnect request");
+ } else if (pktin.type == SSH1_SMSG_SUCCESS ||
+ pktin.type == SSH1_SMSG_FAILURE) {
+ /* ignore */
+ } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
+ char logbuf[100];
+ sprintf(logbuf, "Remote exit status: %d", GET_32BIT(pktin.body));
+ logevent(logbuf);
+ send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
+ logevent("Closing connection");
+ closesocket(s);
+ s = INVALID_SOCKET;
+ } else {
+ fatalbox("Strange packet received: type %d", pktin.type);
+ }
+ }
+
+ return len;
+}
+
+/*
+ * Send a block of data over the SSH link.
+ * Block until all data is sent.
+ * (only used by pSCP)
+ */
+void ssh_scp_send(unsigned char *buf, int len)
+{
+ if (s == INVALID_SOCKET)
+ return;
+ send_packet(SSH1_CMSG_STDIN_DATA,
+ PKT_INT, len, PKT_DATA, buf, len, PKT_END);
+}
+
+/*
+ * Send an EOF notification to the server.
+ * (only used by pSCP)
+ */
+void ssh_scp_send_eof(void)
+{
+ if (s == INVALID_SOCKET)
+ return;
+ send_packet(SSH1_CMSG_EOF, PKT_END);
+}
+
+/*
+ * Set up the connection, login on the remote host and
+ * start execution of a command.
+ * Returns an error message, or NULL on success.
+ * (only used by pSCP)
+ */
+char *ssh_scp_init(char *host, int port, char *cmd, char **realhost)
+{
+ char buf[160], *p;
+
+#ifdef MSCRYPTOAPI
+ if (crypto_startup() == 0)
+ return "Microsoft high encryption pack not installed!";
+#endif
+
+ p = connect_to_host(host, port, realhost);
+ if (p != NULL)
+ return p;
+
+ random_init();
+
+ if (!do_ssh_init())
+ return "Protocol initialisation error";
+
+ /* Exchange keys and login */
+ do {
+ get_packet();
+ if (s == INVALID_SOCKET)
+ return "Connection closed by remote host";
+ } while (!do_ssh1_login(NULL, 0, 1));
+
+ if (ssh_state == SSH_STATE_CLOSED) {
+ closesocket(s);
+ s = INVALID_SOCKET;
+ return "Session initialisation error";
+ }
+
+ /* Execute command */
+ sprintf(buf, "Sending command: %.100s", cmd);
+ logevent(buf);
+ send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
+
+ return NULL;
+}
+
+SOCKET ssh_socket(void) { return s; }
+
Backend ssh_backend = {
ssh_init,
ssh_msg,
ssh_send,
ssh_size,
- ssh_special
+ ssh_special,
+ ssh_socket
};
projects / u / mdw / putty / blobdiff