#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
+
/* Coroutine mechanics for the sillier bits of the code */
#define crBegin1 static int crLine = 0;
#define crBegin2 switch(crLine) { case 0:;
static enum {
SSH_STATE_BEFORE_SIZE,
SSH_STATE_INTERMED,
- SSH_STATE_SESSION
+ SSH_STATE_SESSION,
+ SSH_STATE_CLOSED
} ssh_state = SSH_STATE_BEFORE_SIZE;
static int size_needed = FALSE;
static void c_write (char *buf, int len) {
while (len--) {
int new_head = (inbuf_head + 1) & INBUF_MASK;
- int c = (unsigned char) *buf;
if (new_head != inbuf_reap) {
inbuf[inbuf_head] = *buf++;
inbuf_head = new_head;
static void ssh_gotdata(unsigned char *data, int datalen) {
static long len, biglen, to_read;
- static unsigned char c, *p;
+ static unsigned char *p;
static int i, pad;
- static char padding[8];
- static unsigned char word[4];
crBegin;
while (1) {
pktin.type = pktin.data[pad];
pktin.body = pktin.data+pad+1;
- if (pktin.type == 36) { /* SSH_MSG_DEBUG */
+ if (pktin.type == SSH_MSG_DEBUG) {
/* FIXME: log it */
+ } else if (pktin.type == SSH_MSG_IGNORE) {
+ /* do nothing */;
} else
ssh_protocol(NULL, 0, 1);
}
pktout.length = len-5;
if (pktout.maxlen < biglen) {
pktout.maxlen = biglen;
- pktout.data = (pktout.data == NULL ? malloc(biglen) :
- realloc(pktout.data, biglen));
+ pktout.data = (pktout.data == NULL ? malloc(biglen+4) :
+ realloc(pktout.data, biglen+4));
if (!pktout.data)
fatalbox("Out of memory");
}
s_write(pktout.data, biglen+4);
}
+static int ssh_versioncmp(char *a, char *b) {
+ char *ae, *be;
+ unsigned long av, bv;
+
+ av = strtoul(a, &ae, 10);
+ bv = strtoul(b, &be, 10);
+ if (av != bv) return (av < bv ? -1 : +1);
+ if (*ae == '.') ae++;
+ if (*be == '.') be++;
+ av = strtoul(ae, &ae, 10);
+ bv = strtoul(be, &be, 10);
+ if (av != bv) return (av < bv ? -1 : +1);
+ return 0;
+}
+
static int do_ssh_init(void) {
char c;
char version[10];
break;
}
- sprintf(vstring, "SSH-%s-7.7.7\n",
- (strcmp(version, "1.5") <= 0 ? version : "1.5"));
+ sprintf(vstring, "SSH-%s-PuTTY\n",
+ (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"));
s_write(vstring, strlen(vstring));
+ return 1;
}
static void ssh_protocol(unsigned char *in, int inlen, int ispkt) {
unsigned char cookie[8];
struct RSAKey servkey, hostkey;
struct MD5Context md5c;
+ unsigned long supported_ciphers_mask;
+ int cipher_type;
extern struct ssh_cipher ssh_3des;
+ extern struct ssh_cipher ssh_des;
+ extern struct ssh_cipher ssh_blowfish;
crBegin;
while (!ispkt)
crReturnV;
- if (pktin.type != 2)
+ if (pktin.type != SSH_SMSG_PUBLIC_KEY)
fatalbox("Public key packet not received");
memcpy(cookie, pktin.body, 8);
j = makekey(pktin.body+8+i, &hostkey, &keystr2);
+ 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]);
+
MD5Update(&md5c, keystr2, hostkey.bytes);
MD5Update(&md5c, keystr1, servkey.bytes);
MD5Update(&md5c, pktin.body, 8);
rsaencrypt(rsabuf, hostkey.bytes, &servkey);
}
- s_wrpkt_start(3, len+15);
- pktout.body[0] = 3; /* SSH_CIPHER_3DES */
+ cipher_type = cfg.cipher == CIPHER_BLOWFISH ? SSH_CIPHER_BLOWFISH :
+ cfg.cipher == CIPHER_DES ? SSH_CIPHER_DES :
+ SSH_CIPHER_3DES;
+ if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
+ c_write("Selected cipher not supported, falling back to 3DES\r\n", 53);
+ cipher_type = SSH_CIPHER_3DES;
+ }
+
+ 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;
free(rsabuf);
- cipher = &ssh_3des;
+ cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish :
+ cipher_type == SSH_CIPHER_DES ? &ssh_des :
+ &ssh_3des;
cipher->sesskey(session_key);
do { crReturnV; } while (!ispkt);
- if (pktin.type != 14)
+ if (pktin.type != SSH_SMSG_SUCCESS)
fatalbox("Encryption not successfully enabled");
fflush(stdout);
sprintf(stuff, "Sent username \"%s\".\r\n", username);
c_write(stuff, strlen(stuff));
}
- s_wrpkt_start(4, 4+strlen(username));
+ 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));
do { crReturnV; } while (!ispkt);
- while (pktin.type == 15) {
+ while (pktin.type == SSH_SMSG_FAILURE) {
static char password[100];
static int pos;
static char c;
}
}
c_write("\r\n", 2);
- s_wrpkt_start(9, 4+strlen(password));
+ s_wrpkt_start(SSH_CMSG_AUTH_PASSWORD, 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));
}
}
- i = strlen(cfg.termtype);
- s_wrpkt_start(10, i+5*4+1);
- pktout.body[0] = (i >> 24) & 0xFF;
- pktout.body[1] = (i >> 16) & 0xFF;
- pktout.body[2] = (i >> 8) & 0xFF;
- pktout.body[3] = i & 0xFF;
- memcpy(pktout.body+4, cfg.termtype, i);
- i += 4;
- pktout.body[i++] = (rows >> 24) & 0xFF;
- pktout.body[i++] = (rows >> 16) & 0xFF;
- pktout.body[i++] = (rows >> 8) & 0xFF;
- pktout.body[i++] = rows & 0xFF;
- pktout.body[i++] = (cols >> 24) & 0xFF;
- pktout.body[i++] = (cols >> 16) & 0xFF;
- pktout.body[i++] = (cols >> 8) & 0xFF;
- pktout.body[i++] = cols & 0xFF;
- memset(pktout.body+i, 0, 9); /* 0 pixwidth, 0 pixheight, 0.b endofopt */
- s_wrpkt();
- ssh_state = SSH_STATE_INTERMED;
- do { crReturnV; } while (!ispkt);
- if (pktin.type != 14 && pktin.type != 15) {
- fatalbox("Protocol confusion");
- } else if (pktin.type == 15) {
- c_write("Server refused to allocate pty\r\n", 32);
+ 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_MSG_SUCCESS && pktin.type != SSH_MSG_FAILURE) {
+ fatalbox("Protocol confusion");
+ } else if (pktin.type == SSH_MSG_FAILURE) {
+ c_write("Server refused to allocate pty\r\n", 32);
+ }
}
- s_wrpkt_start(12, 0);
+ s_wrpkt_start(SSH_CMSG_EXEC_SHELL, 0);
s_wrpkt();
ssh_state = SSH_STATE_SESSION;
while (1) {
crReturnV;
if (ispkt) {
- if (pktin.type == 17 || pktin.type == 18) {
+ 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 == 1) {
- /* SSH_MSG_DISCONNECT: do nothing */
- } else if (pktin.type == 14) {
- /* SSH_MSG_SUCCESS: may be from EXEC_SHELL on some servers */
- } else if (pktin.type == 15) {
- /* SSH_MSG_FAILURE: may be from EXEC_SHELL on some servers
+ } else if (pktin.type == SSH_MSG_DISCONNECT) {
+ ssh_state = SSH_STATE_CLOSED;
+ } else if (pktin.type == SSH_MSG_SUCCESS) {
+ /* may be from EXEC_SHELL on some servers */
+ } else if (pktin.type == SSH_MSG_FAILURE) {
+ /* may be from EXEC_SHELL on some servers
* if no pty is available or in other odd cases. Ignore */
- } else if (pktin.type == 20) {
- /* EXITSTATUS */
- s_wrpkt_start(33, 0);
+ } else if (pktin.type == SSH_SMSG_EXITSTATUS) {
+ s_wrpkt_start(SSH_CMSG_EXIT_CONFIRMATION, 0);
s_wrpkt();
} else {
fatalbox("Strange packet received: type %d", pktin.type);
}
} else {
- s_wrpkt_start(16, 4+inlen);
+ 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;
return 1;
case FD_CLOSE:
s = INVALID_SOCKET;
+ ssh_state = SSH_STATE_CLOSED;
return 0;
}
return 1; /* shouldn't happen, but WTF */
static void ssh_size(void) {
switch (ssh_state) {
case SSH_STATE_BEFORE_SIZE:
+ case SSH_STATE_CLOSED:
break; /* do nothing */
case SSH_STATE_INTERMED:
size_needed = TRUE; /* buffer for later */
break;
case SSH_STATE_SESSION:
- s_wrpkt_start(11, 16);
- pktout.body[0] = (rows >> 24) & 0xFF;
- pktout.body[1] = (rows >> 16) & 0xFF;
- pktout.body[2] = (rows >> 8) & 0xFF;
- pktout.body[3] = rows & 0xFF;
- pktout.body[4] = (cols >> 24) & 0xFF;
- pktout.body[5] = (cols >> 16) & 0xFF;
- pktout.body[6] = (cols >> 8) & 0xFF;
- pktout.body[7] = cols & 0xFF;
- memset(pktout.body+8, 0, 8);
- s_wrpkt();
+ if (!cfg.nopty) {
+ 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();
+ }
}
}
~mdw / sgt / putty / blobdiff