if (IS_SCP && (scp_flags & SCP_VERBOSE) != 0) \
fprintf(stderr, "%s\n", s); }
-#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_WINDOW_SIZE 11
-#define SSH_CMSG_EXEC_SHELL 12
-#define SSH_CMSG_EXEC_CMD 13
-#define SSH_SMSG_SUCCESS 14
-#define SSH_SMSG_FAILURE 15
-#define SSH_CMSG_STDIN_DATA 16
-#define SSH_SMSG_STDOUT_DATA 17
-#define SSH_SMSG_STDERR_DATA 18
-#define SSH_CMSG_EOF 19
-#define SSH_SMSG_EXIT_STATUS 20
-#define SSH_CMSG_EXIT_CONFIRMATION 33
-#define SSH_MSG_IGNORE 32
-#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 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_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 GET_32BIT(cp) \
(((unsigned long)(unsigned char)(cp)[0] << 24) | \
#define crStopV do{ crLine = 0; return; }while(0)
#define crWaitUntil(c) do { crReturn(0); } while (!(c))
+extern struct ssh_cipher ssh_3des;
+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, &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_sesskey(unsigned char *key, int len) { }
+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_sesskey, 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 scp_flags = 0;
int (*ssh_get_password)(const char *prompt, char *str, int maxlen) = NULL;
int type;
unsigned char *data;
unsigned char *body;
+ long savedpos;
long maxlen;
};
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 int (*s_rdpkt)(unsigned char **data, int *datalen);
/*
* Collect incoming data in the incoming packet buffer.
- * Decihper and verify the packet when it is completely read.
- * Drop SSH_MSG_DEBUG and SSH_MSG_IGNORE packets.
+ * 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 s_rdpkt(unsigned char **data, int *datalen)
+static int ssh1_rdpkt(unsigned char **data, int *datalen)
{
static long len, pad, biglen, to_read;
static unsigned long realcrc, gotcrc;
if (pktin.maxlen < biglen) {
pktin.maxlen = biglen;
-#ifdef MSCRYPTOAPI
- /* Allocate enough buffer space for extra block
- * for MS CryptEncrypt() */
- pktin.data = (pktin.data == NULL ? malloc(biglen+8) :
- realloc(pktin.data, biglen+8));
-#else
- pktin.data = (pktin.data == NULL ? malloc(biglen) :
- realloc(pktin.data, biglen));
-#endif
+ pktin.data = (pktin.data == NULL ? malloc(biglen+APIEXTRA) :
+ realloc(pktin.data, biglen+APIEXTRA));
if (!pktin.data)
fatalbox("Out of memory");
}
fatalbox("Incorrect CRC received on packet");
}
- if (pktin.type == SSH_SMSG_STDOUT_DATA ||
- pktin.type == SSH_SMSG_STDERR_DATA ||
- pktin.type == SSH_MSG_DEBUG ||
- pktin.type == SSH_SMSG_AUTH_TIS_CHALLENGE) {
+ 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 == SSH_MSG_DEBUG) {
+ if (pktin.type == SSH1_MSG_DEBUG) {
/* log debug message */
char buf[80];
int strlen = GET_32BIT(pktin.body);
buf[8+strlen] = '\0';
logevent(buf);
goto next_packet;
- } else if (pktin.type == SSH_MSG_IGNORE) {
+ } 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;
+
+ pktin.length = payload + 5;
+
+ /*
+ * 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");
+ }
+
+ /*
+ * 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);
+
+ /*
+ * Check the MAC.
+ */
+ if (scmac && !scmac->verify(pktin.data, incoming_sequence++, len+4))
+ fatalbox("Incorrect MAC received on packet");
+
+ pktin.savedpos = 6;
+ pktin.type = pktin.data[5];
+#if 0
+ debug(("Got packet len=%d pad=%d\r\n", len, pad));
+ for (i = 0; i < payload; i++)
+ debug((" %02x", (unsigned char)pktin.data[i]));
+ debug(("\r\n"));
+#endif
+
+ /*
+ * FIXME: handle IGNORE and DEBUG messages.
+ */
+
+ crFinish(0);
+}
+
static void ssh_gotdata(unsigned char *data, int datalen)
{
while (datalen > 0) {
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);
+}
+
static int do_ssh_init(void) {
char c, *vsp;
char version[10];
vlog[strcspn(vlog, "\r\n")] = '\0';
logevent(vlog);
- 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);
- s_write(vstring, strlen(vstring));
+ if (ssh_versioncmp(version, "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;
}
/*
* Handle the key exchange and user authentication phases.
*/
-static int do_ssh_login(unsigned char *in, int inlen, int ispkt)
+static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
{
int i, j, len;
unsigned char session_id[16];
static unsigned long supported_ciphers_mask, supported_auths_mask;
int cipher_type;
- extern struct ssh_cipher ssh_3des;
- extern struct ssh_cipher ssh_des;
- extern struct ssh_cipher ssh_blowfish;
-
crBegin;
if (!ispkt) crWaitUntil(ispkt);
- if (pktin.type != SSH_SMSG_PUBLIC_KEY)
+ if (pktin.type != SSH1_SMSG_PUBLIC_KEY)
fatalbox("Public key packet not received");
logevent("Received public keys");
case SSH_CIPHER_BLOWFISH: logevent("Using Blowfish encryption"); break;
}
- send_packet(SSH_CMSG_SESSION_KEY,
+ send_packet(SSH1_CMSG_SESSION_KEY,
PKT_CHAR, cipher_type,
PKT_DATA, cookie, 8,
PKT_CHAR, (len*8) >> 8, PKT_CHAR, (len*8) & 0xFF,
crWaitUntil(ispkt);
- if (pktin.type != SSH_SMSG_SUCCESS)
+ if (pktin.type != SSH1_SMSG_SUCCESS)
fatalbox("Encryption not successfully enabled");
logevent("Successfully started encryption");
}
}
- send_packet(SSH_CMSG_USER, PKT_STR, username, PKT_END);
+ send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
{
char userlog[20+sizeof(username)];
sprintf(userlog, "Sent username \"%s\"", username);
crWaitUntil(ispkt);
- while (pktin.type == SSH_SMSG_FAILURE) {
+ while (pktin.type == SSH1_SMSG_FAILURE) {
static char password[100];
static int pos;
static char c;
* Show password prompt, having first obtained it via a TIS
* exchange if we're doing TIS authentication.
*/
- pwpkt_type = SSH_CMSG_AUTH_PASSWORD;
+ pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
if (IS_SCP) {
char prompt[200];
}
} else {
- if (pktin.type == SSH_SMSG_FAILURE &&
+ if (pktin.type == SSH1_SMSG_FAILURE &&
cfg.try_tis_auth &&
- (supported_auths_mask & (1<<SSH_AUTH_TIS))) {
- pwpkt_type = SSH_CMSG_AUTH_TIS_RESPONSE;
+ (supported_auths_mask & (1<<SSH1_AUTH_TIS))) {
+ pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
logevent("Requested TIS authentication");
- send_packet(SSH_CMSG_AUTH_TIS, PKT_END);
+ send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
crWaitUntil(ispkt);
- if (pktin.type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
+ if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
logevent("TIS authentication declined");
c_write("TIS authentication refused.\r\n", 29);
} else {
c_write(pktin.body+4, challengelen);
}
}
- if (pwpkt_type == SSH_CMSG_AUTH_PASSWORD)
+ if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD)
c_write("password: ", 10);
pos = 0;
logevent("Sent password");
memset(password, 0, strlen(password));
crWaitUntil(ispkt);
- if (pktin.type == SSH_SMSG_FAILURE) {
+ if (pktin.type == SSH1_SMSG_FAILURE) {
c_write("Access denied\r\n", 15);
logevent("Authentication refused");
- } else if (pktin.type == SSH_MSG_DISCONNECT) {
+ } else if (pktin.type == SSH1_MSG_DISCONNECT) {
logevent("Received disconnect request");
ssh_state = SSH_STATE_CLOSED;
crReturn(1);
- } else if (pktin.type != SSH_SMSG_SUCCESS) {
+ } else if (pktin.type != SSH1_SMSG_SUCCESS) {
fatalbox("Strange packet received, type %d", pktin.type);
}
}
crFinish(1);
}
-static void ssh_protocol(unsigned char *in, int inlen, int ispkt) {
+static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
crBegin;
random_init();
- while (!do_ssh_login(in, inlen, ispkt)) {
+ while (!do_ssh1_login(in, inlen, ispkt)) {
crReturnV;
}
if (ssh_state == SSH_STATE_CLOSED)
crReturnV;
if (!cfg.nopty) {
- send_packet(SSH_CMSG_REQUEST_PTY,
+ send_packet(SSH1_CMSG_REQUEST_PTY,
PKT_STR, cfg.termtype,
PKT_INT, rows, PKT_INT, cols,
PKT_INT, 0, PKT_INT, 0,
PKT_END);
ssh_state = SSH_STATE_INTERMED;
do { crReturnV; } while (!ispkt);
- if (pktin.type != SSH_SMSG_SUCCESS && pktin.type != SSH_SMSG_FAILURE) {
+ if (pktin.type != SSH1_SMSG_SUCCESS && pktin.type != SSH1_SMSG_FAILURE) {
fatalbox("Protocol confusion");
- } else if (pktin.type == SSH_SMSG_FAILURE) {
+ } else if (pktin.type == SSH1_SMSG_FAILURE) {
c_write("Server refused to allocate pty\r\n", 32);
}
logevent("Allocated pty");
}
- send_packet(SSH_CMSG_EXEC_SHELL, PKT_END);
+ send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
logevent("Started session");
ssh_state = SSH_STATE_SESSION;
while (1) {
crReturnV;
if (ispkt) {
- if (pktin.type == SSH_SMSG_STDOUT_DATA ||
- pktin.type == SSH_SMSG_STDERR_DATA) {
+ 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 == SSH_MSG_DISCONNECT) {
+ } else if (pktin.type == SSH1_MSG_DISCONNECT) {
ssh_state = SSH_STATE_CLOSED;
logevent("Received disconnect request");
- } else if (pktin.type == SSH_SMSG_SUCCESS) {
+ } else if (pktin.type == SSH1_SMSG_SUCCESS) {
/* may be from EXEC_SHELL on some servers */
- } else if (pktin.type == SSH_SMSG_FAILURE) {
+ } 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 == SSH_SMSG_EXIT_STATUS) {
- send_packet(SSH_CMSG_EXIT_CONFIRMATION, PKT_END);
+ } 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(SSH_CMSG_STDIN_DATA,
+ send_packet(SSH1_CMSG_STDIN_DATA,
PKT_INT, inlen, PKT_DATA, in, inlen, PKT_END);
}
}
}
/*
+ * 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;
+ 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, outgoing_sequence++,
+ pktout.length + padding);
+ if (cscipher)
+ cscipher->encrypt(pktout.data, pktout.length + padding);
+ maclen = csmac ? csmac->len : 0;
+#if 0
+ debug(("Sending packet len=%d\r\n", pktout.length+padding+maclen));
+ for (i = 0; i < pktout.length+padding+maclen; i++)
+ debug((" %02x", (unsigned char)pktout.data[i]));
+ debug(("\r\n"));
+#endif
+ s_write(pktout.data, pktout.length + padding + maclen);
+}
+
+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.
+ */
+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;
+}
+
+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);
+}
+
+/*
+ * 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 */
+ }
+}
+
+/*
+ * Handle the SSH2 key exchange phase.
+ */
+static int do_ssh2_kex(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;
+ static int hostkeylen, siglen;
+ static unsigned char exchange_hash[20];
+
+ crBegin;
+
+ /*
+ * 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;
+ }
+ }
+ debug(("key exchange is %s\r\n", kex ? kex->name : NULL));
+ debug(("host key alg is %s\r\n", hostkey ? hostkey->name : NULL));
+ debug(("cscipher alg is %s\r\n", cscipher_tobe ? cscipher_tobe->name : NULL));
+ debug(("sccipher alg is %s\r\n", sccipher_tobe ? sccipher_tobe->name : NULL));
+ debug(("csmac alg is %s\r\n", csmac_tobe ? csmac_tobe->name : NULL));
+ debug(("scmac alg is %s\r\n", scmac_tobe ? scmac_tobe->name : NULL));
+ debug(("cscomp alg is %s\r\n", cscomp_tobe ? cscomp_tobe->name : NULL));
+ debug(("sccomp alg is %s\r\n", sccomp_tobe ? sccomp_tobe->name : NULL));
+
+ /*
+ * 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();
+ bndebug("e=", 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();
+ bndebug("f=", f);
+ ssh2_pkt_getstring(&sigdata, &siglen);
+
+ K = dh_find_K(f);
+ bndebug("K=", K);
+
+ sha_string(&exhash, hostkeydata, hostkeylen);
+ sha_mpint(&exhash, e);
+ sha_mpint(&exhash, f);
+ sha_mpint(&exhash, K);
+ SHA_Final(&exhash, exchange_hash);
+
+ debug(("Exchange hash is:\r\n"));
+ for (i = 0; i < 20; i++)
+ debug((" %02x", exchange_hash[i]));
+ debug(("\r\n"));
+
+ /*
+ * FIXME: verify hostkeydata and sigdata.
+ */
+
+ crWaitUntil(0);
+
+ crFinish(1);
+}
+
+static void ssh2_protocol(unsigned char *in, int inlen, int ispkt) {
+ crBegin;
+
+ random_init();
+
+ while (!do_ssh2_kex(in, inlen, ispkt)) {
+ crReturnV;
+ }
+
+ 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().
break;
case SSH_STATE_SESSION:
if (!cfg.nopty) {
- send_packet(SSH_CMSG_WINDOW_SIZE,
+ send_packet(SSH1_CMSG_WINDOW_SIZE,
PKT_INT, rows, PKT_INT, cols,
PKT_INT, 0, PKT_INT, 0, PKT_END);
}
get_packet();
if (s == INVALID_SOCKET)
return 0;
- if (pktin.type == SSH_SMSG_STDOUT_DATA) {
+ if (pktin.type == SSH1_SMSG_STDOUT_DATA) {
int plen = GET_32BIT(pktin.body);
if (plen <= to_read) {
memcpy(buf, pktin.body + 4, plen);
pending_input_ptr = pktin.body + 4 + to_read;
to_read = 0;
}
- } else if (pktin.type == SSH_SMSG_STDERR_DATA) {
+ } 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 == SSH_MSG_DISCONNECT) {
+ } else if (pktin.type == SSH1_MSG_DISCONNECT) {
logevent("Received disconnect request");
- } else if (pktin.type == SSH_SMSG_SUCCESS ||
- pktin.type == SSH_SMSG_FAILURE) {
+ } else if (pktin.type == SSH1_SMSG_SUCCESS ||
+ pktin.type == SSH1_SMSG_FAILURE) {
/* ignore */
- } else if (pktin.type == SSH_SMSG_EXIT_STATUS) {
+ } 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(SSH_CMSG_EXIT_CONFIRMATION, PKT_END);
+ send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
logevent("Closing connection");
closesocket(s);
s = INVALID_SOCKET;
assert(IS_SCP);
if (s == INVALID_SOCKET)
return;
- send_packet(SSH_CMSG_STDIN_DATA,
+ send_packet(SSH1_CMSG_STDIN_DATA,
PKT_INT, len, PKT_DATA, buf, len, PKT_END);
}
assert(IS_SCP);
if (s == INVALID_SOCKET)
return;
- send_packet(SSH_CMSG_EOF, PKT_END);
+ send_packet(SSH1_CMSG_EOF, PKT_END);
}
/*
get_packet();
if (s == INVALID_SOCKET)
return "Connection closed by remote host";
- } while (!do_ssh_login(NULL, 0, 1));
+ } while (!do_ssh1_login(NULL, 0, 1));
if (ssh_state == SSH_STATE_CLOSED) {
closesocket(s);
/* Execute command */
sprintf(buf, "Sending command: %.100s", cmd);
logevent(buf);
- send_packet(SSH_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
+ send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
return NULL;
}
projects / u / mdw / putty / commitdiff