X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/57476f6b080ede65f7b92a4d2b1dd2c2da996fa3..052f07e466e1f69b8c14bc1bbbe8a1df7e38cccc:/ssh.c

diff --git a/ssh.c b/ssh.c
index 6072e7b4..509ea3ab 100644
--- a/ssh.c
+++ b/ssh.c
@@ -263,6 +263,13 @@ static struct rdpkt1_state_tag {
     int chunk;
 } rdpkt1_state;
 
+static struct rdpkt2_state_tag {
+    long len, pad, payload, packetlen, maclen;
+    int i;
+    int cipherblk;
+    unsigned long incoming_sequence;
+} rdpkt2_state;
+
 static int ssh_channelcmp(void *av, void *bv) {
     struct ssh_channel *a = (struct ssh_channel *)av;
     struct ssh_channel *b = (struct ssh_channel *)bv;
@@ -425,29 +432,24 @@ next_packet:
 
 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;
+    struct rdpkt2_state_tag *st = &rdpkt2_state;
 
     crBegin;
 
 next_packet:
-
     pktin.type = 0;
     pktin.length = 0;
-
-    if (cipher)
-        cipherblk = cipher->blksize;
+    if (sccipher)
+        st->cipherblk = sccipher->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));
+        st->cipherblk = 8;
+    if (st->cipherblk < 8)
+        st->cipherblk = 8;
+
+    if (pktin.maxlen < st->cipherblk) {
+	pktin.maxlen = st->cipherblk;
+	pktin.data = (pktin.data == NULL ? malloc(st->cipherblk+APIEXTRA) :
+	              realloc(pktin.data, st->cipherblk+APIEXTRA));
 	if (!pktin.data)
 	    fatalbox("Out of memory");
     }
@@ -456,10 +458,10 @@ next_packet:
      * Acquire and decrypt the first block of the packet. This will
      * contain the length and padding details.
      */
-     for (i = len = 0; i < cipherblk; i++) {
+     for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
 	while ((*datalen) == 0)
-	    crReturn(cipherblk-i);
-	pktin.data[i] = *(*data)++;
+	    crReturn(st->cipherblk-st->i);
+	pktin.data[st->i] = *(*data)++;
         (*datalen)--;
     }
 #ifdef FWHACK
@@ -468,32 +470,32 @@ next_packet:
     }
 #endif
     if (sccipher)
-        sccipher->decrypt(pktin.data, cipherblk);
+        sccipher->decrypt(pktin.data, st->cipherblk);
 
     /*
      * Now get the length and padding figures.
      */
-    len = GET_32BIT(pktin.data);
-    pad = pktin.data[4];
+    st->len = GET_32BIT(pktin.data);
+    st->pad = pktin.data[4];
 
     /*
      * This enables us to deduce the payload length.
      */
-    payload = len - pad - 1;
+    st->payload = st->len - st->pad - 1;
 
-    pktin.length = payload + 5;
+    pktin.length = st->payload + 5;
 
     /*
      * So now we can work out the total packet length.
      */
-    packetlen = len + 4;
-    maclen = scmac ? scmac->len : 0;
+    st->packetlen = st->len + 4;
+    st->maclen = scmac ? scmac->len : 0;
 
     /*
      * Adjust memory allocation if packet is too big.
      */
-    if (pktin.maxlen < packetlen+maclen) {
-	pktin.maxlen = packetlen+maclen;
+    if (pktin.maxlen < st->packetlen+st->maclen) {
+	pktin.maxlen = st->packetlen+st->maclen;
 	pktin.data = (pktin.data == NULL ? malloc(pktin.maxlen+APIEXTRA) :
 	              realloc(pktin.data, pktin.maxlen+APIEXTRA));
 	if (!pktin.data)
@@ -503,31 +505,32 @@ next_packet:
     /*
      * Read and decrypt the remainder of the packet.
      */
-    for (i = cipherblk; i < packetlen + maclen; i++) {
+    for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen; st->i++) {
 	while ((*datalen) == 0)
-	    crReturn(packetlen + maclen - i);
-	pktin.data[i] = *(*data)++;
+	    crReturn(st->packetlen + st->maclen - st->i);
+	pktin.data[st->i] = *(*data)++;
         (*datalen)--;
     }
     /* Decrypt everything _except_ the MAC. */
     if (sccipher)
-        sccipher->decrypt(pktin.data + cipherblk, packetlen - cipherblk);
+        sccipher->decrypt(pktin.data + st->cipherblk,
+                          st->packetlen - st->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(("Got packet len=%d pad=%d\r\n", st->len, st->pad));
+    for (st->i = 0; st->i < st->packetlen; st->i++)
+        debug(("  %02x", (unsigned char)pktin.data[st->i]));
     debug(("\r\n"));
 #endif
 
     /*
      * Check the MAC.
      */
-    if (scmac && !scmac->verify(pktin.data, len+4, incoming_sequence)) {
+    if (scmac && !scmac->verify(pktin.data, st->len+4, st->incoming_sequence)) {
 	bombout(("Incorrect MAC received on packet"));
         crReturn(0);
     }
-    incoming_sequence++;               /* whether or not we MACed */
+    st->incoming_sequence++;               /* whether or not we MACed */
 
     pktin.savedpos = 6;
     pktin.type = pktin.data[5];
@@ -807,7 +810,7 @@ static int ssh_versioncmp(char *a, char *b) {
  * state.
  */
 #include <stdio.h>
-void sha_string(SHA_State *s, void *str, int len) {
+static void sha_string(SHA_State *s, void *str, int len) {
     unsigned char lenblk[4];
     PUT_32BIT(lenblk, len);
     SHA_Bytes(s, lenblk, 4);
@@ -817,7 +820,7 @@ void sha_string(SHA_State *s, void *str, int len) {
 /*
  * SSH2 packet construction functions.
  */
-void ssh2_pkt_adddata(void *data, int len) {
+static void ssh2_pkt_adddata(void *data, int len) {
     pktout.length += len;
     if (pktout.maxlen < pktout.length) {
         pktout.maxlen = pktout.length + 256;
@@ -828,40 +831,40 @@ void ssh2_pkt_adddata(void *data, int len) {
     }
     memcpy(pktout.data+pktout.length-len, data, len);
 }
-void ssh2_pkt_addbyte(unsigned char byte) {
+static void ssh2_pkt_addbyte(unsigned char byte) {
     ssh2_pkt_adddata(&byte, 1);
 }
-void ssh2_pkt_init(int pkt_type) {
+static void ssh2_pkt_init(int pkt_type) {
     pktout.length = 5;
     ssh2_pkt_addbyte((unsigned char)pkt_type);
 }
-void ssh2_pkt_addbool(unsigned char value) {
+static void ssh2_pkt_addbool(unsigned char value) {
     ssh2_pkt_adddata(&value, 1);
 }
-void ssh2_pkt_adduint32(unsigned long value) {
+static 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) {
+static void ssh2_pkt_addstring_start(void) {
     ssh2_pkt_adduint32(0);
     pktout.savedpos = pktout.length;
 }
-void ssh2_pkt_addstring_str(char *data) {
+static void ssh2_pkt_addstring_str(char *data) {
     ssh2_pkt_adddata(data, strlen(data));
     PUT_32BIT(pktout.data + pktout.savedpos - 4,
               pktout.length - pktout.savedpos);
 }
-void ssh2_pkt_addstring_data(char *data, int len) {
+static void ssh2_pkt_addstring_data(char *data, int len) {
     ssh2_pkt_adddata(data, len);
     PUT_32BIT(pktout.data + pktout.savedpos - 4,
               pktout.length - pktout.savedpos);
 }
-void ssh2_pkt_addstring(char *data) {
+static void ssh2_pkt_addstring(char *data) {
     ssh2_pkt_addstring_start();
     ssh2_pkt_addstring_str(data);
 }
-char *ssh2_mpint_fmt(Bignum b, int *len) {
+static char *ssh2_mpint_fmt(Bignum b, int *len) {
     unsigned char *p;
     int i, n = b[0];
     p = malloc(n * 2 + 1);
@@ -879,7 +882,7 @@ char *ssh2_mpint_fmt(Bignum b, int *len) {
     *len = n*2+1-i;
     return p;
 }
-void ssh2_pkt_addmp(Bignum b) {
+static void ssh2_pkt_addmp(Bignum b) {
     unsigned char *p;
     int len;
     p = ssh2_mpint_fmt(b, &len);
@@ -887,7 +890,7 @@ void ssh2_pkt_addmp(Bignum b) {
     ssh2_pkt_addstring_data(p, len);
     free(p);
 }
-void ssh2_pkt_send(void) {
+static void ssh2_pkt_send(void) {
     int cipherblk, maclen, padding, i;
     static unsigned long outgoing_sequence = 0;
 
@@ -935,7 +938,7 @@ void bndebug(char *string, Bignum b) {
 }
 #endif
 
-void sha_mpint(SHA_State *s, Bignum b) {
+static void sha_mpint(SHA_State *s, Bignum b) {
     unsigned char *p;
     int len;
     p = ssh2_mpint_fmt(b, &len);
@@ -946,7 +949,7 @@ void sha_mpint(SHA_State *s, Bignum b) {
 /*
  * SSH2 packet decode functions.
  */
-unsigned long ssh2_pkt_getuint32(void) {
+static unsigned long ssh2_pkt_getuint32(void) {
     unsigned long value;
     if (pktin.length - pktin.savedpos < 4)
         return 0;                      /* arrgh, no way to decline (FIXME?) */
@@ -954,7 +957,7 @@ unsigned long ssh2_pkt_getuint32(void) {
     pktin.savedpos += 4;
     return value;
 }
-void ssh2_pkt_getstring(char **p, int *length) {
+static void ssh2_pkt_getstring(char **p, int *length) {
     *p = NULL;
     if (pktin.length - pktin.savedpos < 4)
         return;
@@ -965,7 +968,7 @@ void ssh2_pkt_getstring(char **p, int *length) {
     *p = pktin.data+pktin.savedpos;
     pktin.savedpos += *length;
 }
-Bignum ssh2_pkt_getmp(void) {
+static Bignum ssh2_pkt_getmp(void) {
     char *p;
     int i, j, length;
     Bignum b;
@@ -1028,6 +1031,8 @@ static int do_ssh_init(void) {
 	    break;
     }
 
+    rdpkt2_state.incoming_sequence = 0;
+
     *vsp = 0;
     sprintf(vlog, "Server version: %s", vstring);
     vlog[strcspn(vlog, "\r\n")] = '\0';
@@ -1089,6 +1094,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
     static int tried_publickey;
     static unsigned char session_id[16];
     int cipher_type;
+    static char username[100];
 
     crBegin;
 
@@ -1212,7 +1218,6 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
 
     fflush(stdout);
     {
-	static char username[100];
 	static int pos = 0;
 	static char c;
 	if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
@@ -1440,7 +1445,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
         }
         if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
             sprintf(prompt, "%.90s@%.90s's password: ",
-                    cfg.username, savedhost);
+                    username, savedhost);
         }
         if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
             char *comment = NULL;
@@ -1455,7 +1460,7 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
             free(comment);
         }
 
-	if (!(flags & FLAG_INTERACTIVE)) {
+	if (ssh_get_password) {
 	    if (!ssh_get_password(prompt, password, sizeof(password))) {
                 /*
                  * get_password failed to get a password (for
@@ -1771,7 +1776,7 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
 /*
  * Utility routine for decoding comma-separated strings in KEXINIT.
  */
-int in_commasep_string(char *needle, char *haystack, int haylen) {
+static int in_commasep_string(char *needle, char *haystack, int haylen) {
     int needlen = strlen(needle);
     while (1) {
         /*
@@ -1798,7 +1803,7 @@ int in_commasep_string(char *needle, char *haystack, int haylen) {
 /*
  * SSH2 key creation method.
  */
-void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
+static void ssh2_mkkey(Bignum K, char *H, char chr, char *keyspace) {
     SHA_State s;
     /* First 20 bytes. */
     SHA_Init(&s);
@@ -1876,18 +1881,18 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
     }
     /* List client->server encryption algorithms. */
     ssh2_pkt_addstring_start();
-    for (i = -1; i < lenof(ciphers); i++) {
-        const struct ssh_cipher *c = i<0 ? preferred_cipher : ciphers[i];
+    for (i = 0; i < lenof(ciphers)+1; i++) {
+        const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
         ssh2_pkt_addstring_str(c->name);
-        if (i < lenof(ciphers)-1)
+        if (i < lenof(ciphers))
             ssh2_pkt_addstring_str(",");
     }
     /* List server->client encryption algorithms. */
     ssh2_pkt_addstring_start();
-    for (i = -1; i < lenof(ciphers); i++) {
-        const struct ssh_cipher *c = i<0 ? preferred_cipher : ciphers[i];
+    for (i = 0; i < lenof(ciphers)+1; i++) {
+        const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
         ssh2_pkt_addstring_str(c->name);
-        if (i < lenof(ciphers)-1)
+        if (i < lenof(ciphers))
             ssh2_pkt_addstring_str(",");
     }
     /* List client->server MAC algorithms. */
@@ -1958,18 +1963,18 @@ static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
         }
     }
     ssh2_pkt_getstring(&str, &len);    /* client->server cipher */
-    for (i = -1; i < lenof(ciphers); i++) {
-        const struct ssh_cipher *c = i<0 ? preferred_cipher : ciphers[i];
+    for (i = 0; i < lenof(ciphers)+1; i++) {
+        const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
         if (in_commasep_string(c->name, str, len)) {
-            cscipher_tobe = ciphers[i];
+            cscipher_tobe = c;
             break;
         }
     }
     ssh2_pkt_getstring(&str, &len);    /* server->client cipher */
-    for (i = -1; i < lenof(ciphers); i++) {
-        const struct ssh_cipher *c = i<0 ? preferred_cipher : ciphers[i];
+    for (i = 0; i < lenof(ciphers)+1; i++) {
+        const struct ssh_cipher *c = i==0 ? preferred_cipher : ciphers[i-1];
         if (in_commasep_string(c->name, str, len)) {
-            sccipher_tobe = ciphers[i];
+            sccipher_tobe = c;
             break;
         }
     }
@@ -2193,9 +2198,9 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
 	    }
 	}
 
-	if (!(flags & FLAG_INTERACTIVE)) {
+	if (ssh_get_password) {
 	    char prompt[200];
-	    sprintf(prompt, "%.90s@%.90s's password: ", cfg.username, savedhost);
+	    sprintf(prompt, "%.90s@%.90s's password: ", username, savedhost);
 	    if (!ssh_get_password(prompt, password, sizeof(password))) {
                 /*
                  * get_password failed to get a password (for
@@ -2606,6 +2611,14 @@ static void ssh_special (Telnet_Special code) {
             ssh2_pkt_send();
         }
         logevent("Sent EOF message");
+    } else if (code == TS_PING) {
+        if (ssh_version == 1) {
+            send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
+        } else {
+            ssh2_pkt_init(SSH2_MSG_IGNORE);
+            ssh2_pkt_addstring_start();
+            ssh2_pkt_send();
+        }
     } else {
         /* do nothing */
     }
@@ -2622,5 +2635,6 @@ Backend ssh_backend = {
     ssh_size,
     ssh_special,
     ssh_socket,
-    ssh_sendok
+    ssh_sendok,
+    22
 };