+/*
+ * SSH backend.
+ */
+
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <assert.h>
+#include <limits.h>
+#include <signal.h>
#include "putty.h"
#include "tree234.h"
#define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
#define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
#define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
+#define SSH2_MSG_KEXRSA_PUBKEY 30 /* 0x1e */
+#define SSH2_MSG_KEXRSA_SECRET 31 /* 0x1f */
+#define SSH2_MSG_KEXRSA_DONE 32 /* 0x20 */
#define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
#define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
#define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
* Packet type contexts, so that ssh2_pkt_type can correctly decode
* the ambiguous type numbers back into the correct type strings.
*/
-#define SSH2_PKTCTX_DHGROUP 0x0001
-#define SSH2_PKTCTX_DHGEX 0x0002
-#define SSH2_PKTCTX_KEX_MASK 0x000F
-#define SSH2_PKTCTX_PUBLICKEY 0x0010
-#define SSH2_PKTCTX_PASSWORD 0x0020
-#define SSH2_PKTCTX_KBDINTER 0x0040
-#define SSH2_PKTCTX_AUTH_MASK 0x00F0
+typedef enum {
+ SSH2_PKTCTX_NOKEX,
+ SSH2_PKTCTX_DHGROUP,
+ SSH2_PKTCTX_DHGEX,
+ SSH2_PKTCTX_RSAKEX
+} Pkt_KCtx;
+typedef enum {
+ SSH2_PKTCTX_NOAUTH,
+ SSH2_PKTCTX_PUBLICKEY,
+ SSH2_PKTCTX_PASSWORD,
+ SSH2_PKTCTX_KBDINTER
+} Pkt_ACtx;
#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
static const char *const ssh2_disconnect_reasons[] = {
NULL,
- "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
- "SSH_DISCONNECT_PROTOCOL_ERROR",
- "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
- "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
- "SSH_DISCONNECT_MAC_ERROR",
- "SSH_DISCONNECT_COMPRESSION_ERROR",
- "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
- "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
- "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
- "SSH_DISCONNECT_CONNECTION_LOST",
- "SSH_DISCONNECT_BY_APPLICATION",
- "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
- "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
- "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
- "SSH_DISCONNECT_ILLEGAL_USER_NAME",
+ "host not allowed to connect",
+ "protocol error",
+ "key exchange failed",
+ "host authentication failed",
+ "MAC error",
+ "compression error",
+ "service not available",
+ "protocol version not supported",
+ "host key not verifiable",
+ "connection lost",
+ "by application",
+ "too many connections",
+ "auth cancelled by user",
+ "no more auth methods available",
+ "illegal user name",
};
#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
}
#define translate(x) if (type == x) return #x
-#define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
+#define translatek(x,ctx) if (type == x && (pkt_kctx == ctx)) return #x
+#define translatea(x,ctx) if (type == x && (pkt_actx == ctx)) return #x
static char *ssh1_pkt_type(int type)
{
translate(SSH1_MSG_DISCONNECT);
translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
return "unknown";
}
-static char *ssh2_pkt_type(int pkt_ctx, int type)
+static char *ssh2_pkt_type(Pkt_KCtx pkt_kctx, Pkt_ACtx pkt_actx, int type)
{
translate(SSH2_MSG_DISCONNECT);
translate(SSH2_MSG_IGNORE);
translate(SSH2_MSG_SERVICE_ACCEPT);
translate(SSH2_MSG_KEXINIT);
translate(SSH2_MSG_NEWKEYS);
- translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP);
- translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP);
- translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
- translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
- translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
- translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
+ translatek(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP);
+ translatek(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP);
+ translatek(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
+ translatek(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
+ translatek(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
+ translatek(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
+ translatek(SSH2_MSG_KEXRSA_PUBKEY, SSH2_PKTCTX_RSAKEX);
+ translatek(SSH2_MSG_KEXRSA_SECRET, SSH2_PKTCTX_RSAKEX);
+ translatek(SSH2_MSG_KEXRSA_DONE, SSH2_PKTCTX_RSAKEX);
translate(SSH2_MSG_USERAUTH_REQUEST);
translate(SSH2_MSG_USERAUTH_FAILURE);
translate(SSH2_MSG_USERAUTH_SUCCESS);
translate(SSH2_MSG_USERAUTH_BANNER);
- translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
- translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
- translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
- translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
+ translatea(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
+ translatea(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
+ translatea(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
+ translatea(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
translate(SSH2_MSG_GLOBAL_REQUEST);
translate(SSH2_MSG_REQUEST_SUCCESS);
translate(SSH2_MSG_REQUEST_FAILURE);
#define OUR_V2_WINSIZE 16384
#define OUR_V2_MAXPKT 0x4000UL
+/* Maximum length of passwords/passphrases (arbitrary) */
+#define SSH_MAX_PASSWORD_LEN 100
+
const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
const static struct ssh_mac *macs[] = {
- &ssh_sha1, &ssh_md5
+ &ssh_hmac_sha1, &ssh_hmac_sha1_96, &ssh_hmac_md5
};
const static struct ssh_mac *buggymacs[] = {
- &ssh_sha1_buggy, &ssh_md5
+ &ssh_hmac_sha1_buggy, &ssh_hmac_sha1_96_buggy, &ssh_hmac_md5
};
static void *ssh_comp_none_init(void)
struct ssh2_data_channel {
bufchain outbuffer;
unsigned remwindow, remmaxpkt;
- unsigned locwindow;
+ /* locwindow is signed so we can cope with excess data. */
+ int locwindow;
} v2;
} v;
union {
const struct plug_function_table *fn;
/* the above field _must_ be first in the structure */
- SHA_State exhash, exhashbase;
+ char *v_c, *v_s;
+ void *exhash;
Socket s;
void *cs_comp_ctx, *sc_comp_ctx;
const struct ssh_kex *kex;
const struct ssh_signkey *hostkey;
- unsigned char v2_session_id[20];
+ unsigned char v2_session_id[SSH2_KEX_MAX_HASH_LEN];
+ int v2_session_id_len;
void *kex_ctx;
char *savedhost;
tree234 *channels; /* indexed by local id */
struct ssh_channel *mainchan; /* primary session channel */
+ int ncmode; /* is primary channel direct-tcpip? */
int exitcode;
int close_expected;
+ int clean_exit;
tree234 *rportfwds, *portfwds;
int fallback_cmd;
bufchain banner; /* accumulates banners during do_ssh2_authconn */
- /*
- * Used for username and password input.
- */
- char *userpass_input_buffer;
- int userpass_input_buflen;
- int userpass_input_bufpos;
- int userpass_input_echo;
- int pkt_ctx;
+ Pkt_KCtx pkt_kctx;
+ Pkt_ACtx pkt_actx;
void *x11auth;
return low + 1 + CHANNEL_NUMBER_OFFSET;
}
+static void c_write_stderr(int trusted, const char *buf, int len)
+{
+ int i;
+ for (i = 0; i < len; i++)
+ if (buf[i] != '\r' && (trusted || buf[i] == '\n' || (buf[i] & 0x60)))
+ fputc(buf[i], stderr);
+}
+
static void c_write(Ssh ssh, const char *buf, int len)
{
- if ((flags & FLAG_STDERR)) {
- int i;
- for (i = 0; i < len; i++)
- if (buf[i] != '\r')
- fputc(buf[i], stderr);
- return;
- }
- from_backend(ssh->frontend, 1, buf, len);
+ if (flags & FLAG_STDERR)
+ c_write_stderr(1, buf, len);
+ else
+ from_backend(ssh->frontend, 1, buf, len);
}
static void c_write_untrusted(Ssh ssh, const char *buf, int len)
{
- int i;
- for (i = 0; i < len; i++) {
- if (buf[i] == '\n')
- c_write(ssh, "\r\n", 2);
- else if ((buf[i] & 0x60) || (buf[i] == '\r'))
- c_write(ssh, buf + i, 1);
- }
+ if (flags & FLAG_STDERR)
+ c_write_stderr(0, buf, len);
+ else
+ from_backend_untrusted(ssh->frontend, buf, len);
}
static void c_write_str(Ssh ssh, const char *buf)
/* "Session data" packets - omit the data field */
if ((st->pktin->type == SSH1_SMSG_STDOUT_DATA) ||
(st->pktin->type == SSH1_SMSG_STDERR_DATA)) {
- do_blank = TRUE; blank_prefix = 0;
- } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
do_blank = TRUE; blank_prefix = 4;
+ } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
+ do_blank = TRUE; blank_prefix = 8;
}
if (do_blank) {
blank.offset = blank_prefix;
* _Completely_ silly lengths should be stomped on before they
* do us any more damage.
*/
- if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
+ if (st->len < 0 || st->len > 35000 || st->pad < 4 ||
+ st->len - st->pad < 1 || (st->len + 4) % st->cipherblk != 0) {
bombout(("Incoming packet was garbled on decryption"));
ssh_free_packet(st->pktin);
crStop(NULL);
int do_blank = FALSE, blank_prefix = 0;
/* "Session data" packets - omit the data field */
if (st->pktin->type == SSH2_MSG_CHANNEL_DATA) {
- do_blank = TRUE; blank_prefix = 4;
- } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
do_blank = TRUE; blank_prefix = 8;
+ } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
+ do_blank = TRUE; blank_prefix = 12;
}
if (do_blank) {
blank.offset = blank_prefix;
}
}
log_packet(ssh->logctx, PKT_INCOMING, st->pktin->type,
- ssh2_pkt_type(ssh->pkt_ctx, st->pktin->type),
+ ssh2_pkt_type(ssh->pkt_kctx, ssh->pkt_actx,
+ st->pktin->type),
st->pktin->data+6, st->pktin->length-6,
nblanks, &blank);
}
zlib_compress_block(ssh->cs_comp_ctx,
pkt->data + 12, pkt->length - 12,
&compblk, &complen);
+ ssh_pkt_ensure(pkt, complen + 2); /* just in case it's got bigger */
memcpy(pkt->data + 12, compblk, complen);
sfree(compblk);
pkt->length = complen + 12;
return biglen + 4; /* len(length+padding+type+data+CRC) */
}
+static int s_write(Ssh ssh, void *data, int len)
+{
+ if (ssh->logctx)
+ log_packet(ssh->logctx, PKT_OUTGOING, -1, NULL, data, len, 0, NULL);
+ return sk_write(ssh->s, (char *)data, len);
+}
+
static void s_wrpkt(Ssh ssh, struct Packet *pkt)
{
int len, backlog, offset;
len = s_wrpkt_prepare(ssh, pkt, &offset);
- backlog = sk_write(ssh->s, (char *)pkt->data + offset, len);
+ backlog = s_write(ssh, pkt->data + offset, len);
if (backlog > SSH_MAX_BACKLOG)
ssh_throttle_all(ssh, 1, backlog);
ssh_free_packet(pkt);
while ((argtype = va_arg(ap, int)) != PKT_END) {
unsigned char *argp, argchar;
+ char *sargp;
unsigned long argint;
int arglen;
switch (argtype) {
ssh_pkt_adddata(pkt, argp, arglen);
break;
case PKT_STR:
- argp = va_arg(ap, unsigned char *);
- ssh_pkt_addstring(pkt, argp);
+ sargp = va_arg(ap, char *);
+ ssh_pkt_addstring(pkt, sargp);
break;
case PKT_BIGNUM:
bn = va_arg(ap, Bignum);
/*
* Utility routines for putting an SSH-protocol `string' and
- * `uint32' into a SHA state.
+ * `uint32' into a hash state.
*/
-static void sha_string(SHA_State * s, void *str, int len)
+static void hash_string(const struct ssh_hash *h, void *s, void *str, int len)
{
unsigned char lenblk[4];
PUT_32BIT(lenblk, len);
- SHA_Bytes(s, lenblk, 4);
- SHA_Bytes(s, str, len);
+ h->bytes(s, lenblk, 4);
+ h->bytes(s, str, len);
}
-static void sha_uint32(SHA_State * s, unsigned i)
+static void hash_uint32(const struct ssh_hash *h, void *s, unsigned i)
{
unsigned char intblk[4];
PUT_32BIT(intblk, i);
- SHA_Bytes(s, intblk, 4);
+ h->bytes(s, intblk, 4);
}
/*
{
if (pkt->maxlen < length) {
unsigned char *body = pkt->body;
- int offset = body ? pkt->data - body : 0;
+ int offset = body ? body - pkt->data : 0;
pkt->maxlen = length + 256;
pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
if (body) pkt->body = pkt->data + offset;
static void ssh1_pkt_addmp(struct Packet *pkt, Bignum b)
{
int len = ssh1_bignum_length(b);
- unsigned char *data = snewn(len, char);
+ unsigned char *data = snewn(len, unsigned char);
(void) ssh1_write_bignum(data, b);
ssh_pkt_adddata(pkt, data, len);
sfree(data);
unsigned char *p;
int i, n = (bignum_bitcount(b) + 7) / 8;
p = snewn(n + 1, unsigned char);
- if (!p)
- fatalbox("out of memory");
p[0] = 0;
for (i = 1; i <= n; i++)
p[i] = bignum_byte(b, n - i);
static struct Packet *ssh2_pkt_init(int pkt_type)
{
struct Packet *pkt = ssh_new_packet();
- pkt->length = 5;
+ pkt->length = 5; /* space for packet length + padding length */
pkt->forcepad = 0;
ssh_pkt_addbyte(pkt, (unsigned char) pkt_type);
- pkt->body = pkt->data + pkt->length;
+ pkt->body = pkt->data + pkt->length; /* after packet type */
return pkt;
}
if (ssh->logctx)
log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
- ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
+ ssh2_pkt_type(ssh->pkt_kctx, ssh->pkt_actx, pkt->data[5]),
pkt->body, pkt->length - (pkt->body - pkt->data),
pkt->nblanks, pkt->blanks);
sfree(pkt->blanks); pkt->blanks = NULL;
return;
}
len = ssh2_pkt_construct(ssh, pkt);
- backlog = sk_write(ssh->s, (char *)pkt->data, len);
+ backlog = s_write(ssh, pkt->data, len);
if (backlog > SSH_MAX_BACKLOG)
ssh_throttle_all(ssh, 1, backlog);
* get encrypted with a known IV.
*/
struct Packet *ipkt = ssh2_pkt_init(SSH2_MSG_IGNORE);
+ ssh2_pkt_addstring_start(ipkt);
ssh2_pkt_defer_noqueue(ssh, ipkt, TRUE);
}
len = ssh2_pkt_construct(ssh, pkt);
ssh2_pkt_send_noqueue(ssh, pkt);
}
-#if 0 /* disused */
/*
* Either queue or defer a packet, depending on whether queueing is
* set.
else
ssh2_pkt_defer_noqueue(ssh, pkt, FALSE);
}
-#endif
/*
* Send the whole deferred data block constructed by
static void ssh_pkt_defersend(Ssh ssh)
{
int backlog;
- backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
- ssh->deferred_len);
+ backlog = s_write(ssh, ssh->deferred_send_data, ssh->deferred_len);
ssh->deferred_len = ssh->deferred_size = 0;
sfree(ssh->deferred_send_data);
ssh->deferred_send_data = NULL;
}
/*
+ * Send a packet whose length needs to be disguised (typically
+ * passwords or keyboard-interactive responses).
+ */
+static void ssh2_pkt_send_with_padding(Ssh ssh, struct Packet *pkt,
+ int padsize)
+{
+#if 0
+ if (0) {
+ /*
+ * The simplest way to do this is to adjust the
+ * variable-length padding field in the outgoing packet.
+ *
+ * Currently compiled out, because some Cisco SSH servers
+ * don't like excessively padded packets (bah, why's it
+ * always Cisco?)
+ */
+ pkt->forcepad = padsize;
+ ssh2_pkt_send(ssh, pkt);
+ } else
+#endif
+ {
+ /*
+ * If we can't do that, however, an alternative approach is
+ * to use the pkt_defer mechanism to bundle the packet
+ * tightly together with an SSH_MSG_IGNORE such that their
+ * combined length is a constant. So first we construct the
+ * final form of this packet and defer its sending.
+ */
+ ssh2_pkt_defer(ssh, pkt);
+
+ /*
+ * Now construct an SSH_MSG_IGNORE which includes a string
+ * that's an exact multiple of the cipher block size. (If
+ * the cipher is NULL so that the block size is
+ * unavailable, we don't do this trick at all, because we
+ * gain nothing by it.)
+ */
+ if (ssh->cscipher) {
+ int stringlen, i;
+
+ stringlen = (256 - ssh->deferred_len);
+ stringlen += ssh->cscipher->blksize - 1;
+ stringlen -= (stringlen % ssh->cscipher->blksize);
+ if (ssh->cscomp) {
+ /*
+ * Temporarily disable actual compression, so we
+ * can guarantee to get this string exactly the
+ * length we want it. The compression-disabling
+ * routine should return an integer indicating how
+ * many bytes we should adjust our string length
+ * by.
+ */
+ stringlen -=
+ ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
+ }
+ pkt = ssh2_pkt_init(SSH2_MSG_IGNORE);
+ ssh2_pkt_addstring_start(pkt);
+ for (i = 0; i < stringlen; i++) {
+ char c = (char) random_byte();
+ ssh2_pkt_addstring_data(pkt, &c, 1);
+ }
+ ssh2_pkt_defer(ssh, pkt);
+ }
+ ssh_pkt_defersend(ssh);
+ }
+}
+
+/*
* Send all queued SSH-2 packets. We send them by means of
* ssh2_pkt_defer_noqueue(), in case they included a pair of
* packets that needed to be lumped together.
}
#endif
-static void sha_mpint(SHA_State * s, Bignum b)
+static void hash_mpint(const struct ssh_hash *h, void *s, Bignum b)
{
unsigned char *p;
int len;
p = ssh2_mpint_fmt(b, &len);
- sha_string(s, p, len);
+ hash_string(h, s, p, len);
sfree(p);
}
ssh->remote_bugs = 0;
+ /*
+ * General notes on server version strings:
+ * - Not all servers reporting "Cisco-1.25" have all the bugs listed
+ * here -- in particular, we've heard of one that's perfectly happy
+ * with SSH1_MSG_IGNOREs -- but this string never seems to change,
+ * so we can't distinguish them.
+ */
if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
(ssh->cfg.sshbug_ignore1 == AUTO &&
(!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
(ssh->cfg.sshbug_rekey2 == AUTO &&
- (wc_match("OpenSSH_2.[0-4]*", imp) ||
+ (wc_match("DigiSSH_2.0", imp) ||
+ wc_match("OpenSSH_2.[0-4]*", imp) ||
wc_match("OpenSSH_2.5.[0-3]*", imp) ||
wc_match("Sun_SSH_1.0", imp) ||
- wc_match("Sun_SSH_1.0.1", imp)))) {
+ wc_match("Sun_SSH_1.0.1", imp) ||
+ /* All versions <= 1.2.6 (they changed their format in 1.2.7) */
+ wc_match("WeOnlyDo-*", imp)))) {
/*
* These versions have the SSH-2 rekey bug.
*/
}
}
+/*
+ * Send an appropriate SSH version string.
+ */
+static void ssh_send_verstring(Ssh ssh, char *svers)
+{
+ char *verstring;
+
+ if (ssh->version == 2) {
+ /*
+ * Construct a v2 version string.
+ */
+ verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
+ } else {
+ /*
+ * Construct a v1 version string.
+ */
+ verstring = dupprintf("SSH-%s-%s\012",
+ (ssh_versioncmp(svers, "1.5") <= 0 ?
+ svers : "1.5"),
+ sshver);
+ }
+
+ ssh_fix_verstring(verstring);
+
+ if (ssh->version == 2) {
+ size_t len;
+ /*
+ * Record our version string.
+ */
+ len = strcspn(verstring, "\015\012");
+ ssh->v_c = snewn(len + 1, char);
+ memcpy(ssh->v_c, verstring, len);
+ ssh->v_c[len] = 0;
+ }
+
+ logeventf(ssh, "We claim version: %.*s",
+ strcspn(verstring, "\015\012"), verstring);
+ s_write(ssh, verstring, strlen(verstring));
+ sfree(verstring);
+}
+
static int do_ssh_init(Ssh ssh, unsigned char c)
{
struct do_ssh_init_state {
crBegin(ssh->do_ssh_init_crstate);
- /* Search for the string "SSH-" in the input. */
- s->i = 0;
- while (1) {
- static const int transS[] = { 1, 2, 2, 1 };
- static const int transH[] = { 0, 0, 3, 0 };
- static const int transminus[] = { 0, 0, 0, -1 };
- if (c == 'S')
- s->i = transS[s->i];
- else if (c == 'H')
- s->i = transH[s->i];
- else if (c == '-')
- s->i = transminus[s->i];
- else
- s->i = 0;
- if (s->i < 0)
- break;
- crReturn(1); /* get another character */
+ /* Search for a line beginning with the string "SSH-" in the input. */
+ for (;;) {
+ if (c != 'S') goto no;
+ crReturn(1);
+ if (c != 'S') goto no;
+ crReturn(1);
+ if (c != 'H') goto no;
+ crReturn(1);
+ if (c != '-') goto no;
+ break;
+ no:
+ while (c != '\012')
+ crReturn(1);
+ crReturn(1);
}
s->vstrsize = 16;
crStop(0);
}
- {
- char *verstring;
-
- if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
- /*
- * Construct a v2 version string.
- */
- verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
- ssh->version = 2;
- } else {
- /*
- * Construct a v1 version string.
- */
- verstring = dupprintf("SSH-%s-%s\012",
- (ssh_versioncmp(s->version, "1.5") <= 0 ?
- s->version : "1.5"),
- sshver);
- ssh->version = 1;
- }
+ if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1))
+ ssh->version = 2;
+ else
+ ssh->version = 1;
- ssh_fix_verstring(verstring);
+ logeventf(ssh, "Using SSH protocol version %d", ssh->version);
- if (ssh->version == 2) {
- /*
- * Hash our version string and their version string.
- */
- SHA_Init(&ssh->exhashbase);
- sha_string(&ssh->exhashbase, verstring,
- strcspn(verstring, "\015\012"));
- sha_string(&ssh->exhashbase, s->vstring,
- strcspn(s->vstring, "\015\012"));
+ /* Send the version string, if we haven't already */
+ if (ssh->cfg.sshprot != 3)
+ ssh_send_verstring(ssh, s->version);
- /*
- * Initialise SSH-2 protocol.
- */
- ssh->protocol = ssh2_protocol;
- ssh2_protocol_setup(ssh);
- ssh->s_rdpkt = ssh2_rdpkt;
- } else {
- /*
- * Initialise SSH-1 protocol.
- */
- ssh->protocol = ssh1_protocol;
- ssh1_protocol_setup(ssh);
- ssh->s_rdpkt = ssh1_rdpkt;
- }
- logeventf(ssh, "We claim version: %.*s",
- strcspn(verstring, "\015\012"), verstring);
- sk_write(ssh->s, verstring, strlen(verstring));
- sfree(verstring);
- if (ssh->version == 2)
- do_ssh2_transport(ssh, NULL, -1, NULL);
+ if (ssh->version == 2) {
+ size_t len;
+ /*
+ * Record their version string.
+ */
+ len = strcspn(s->vstring, "\015\012");
+ ssh->v_s = snewn(len + 1, char);
+ memcpy(ssh->v_s, s->vstring, len);
+ ssh->v_s[len] = 0;
+
+ /*
+ * Initialise SSH-2 protocol.
+ */
+ ssh->protocol = ssh2_protocol;
+ ssh2_protocol_setup(ssh);
+ ssh->s_rdpkt = ssh2_rdpkt;
+ } else {
+ /*
+ * Initialise SSH-1 protocol.
+ */
+ ssh->protocol = ssh1_protocol;
+ ssh1_protocol_setup(ssh);
+ ssh->s_rdpkt = ssh1_rdpkt;
}
-
- logeventf(ssh, "Using SSH protocol version %d", ssh->version);
+ if (ssh->version == 2)
+ do_ssh2_transport(ssh, NULL, -1, NULL);
update_specials_menu(ssh->frontend);
ssh->state = SSH_STATE_BEFORE_SIZE;
static void ssh_process_incoming_data(Ssh ssh,
unsigned char **data, int *datalen)
{
- struct Packet *pktin = ssh->s_rdpkt(ssh, data, datalen);
+ struct Packet *pktin;
+
+ pktin = ssh->s_rdpkt(ssh, data, datalen);
if (pktin) {
ssh->protocol(ssh, NULL, 0, pktin);
ssh_free_packet(pktin);
static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
{
+ /* Log raw data, if we're in that mode. */
+ if (ssh->logctx)
+ log_packet(ssh->logctx, PKT_INCOMING, -1, NULL, data, datalen,
+ 0, NULL);
+
crBegin(ssh->ssh_gotdata_crstate);
/*
* everything to s_rdpkt, and then pass the resulting packets
* to the proper protocol handler.
*/
- if (datalen == 0)
- crReturnV;
-
- /*
- * Process queued data if there is any.
- */
- ssh_process_queued_incoming_data(ssh);
while (1) {
- while (datalen > 0) {
- if (ssh->frozen)
+ while (bufchain_size(&ssh->queued_incoming_data) > 0 || datalen > 0) {
+ if (ssh->frozen) {
ssh_queue_incoming_data(ssh, &data, &datalen);
-
- ssh_process_incoming_data(ssh, &data, &datalen);
-
+ /* This uses up all data and cannot cause anything interesting
+ * to happen; indeed, for anything to happen at all, we must
+ * return, so break out. */
+ break;
+ } else if (bufchain_size(&ssh->queued_incoming_data) > 0) {
+ /* This uses up some or all data, and may freeze the
+ * session. */
+ ssh_process_queued_incoming_data(ssh);
+ } else {
+ /* This uses up some or all data, and may freeze the
+ * session. */
+ ssh_process_incoming_data(ssh, &data, &datalen);
+ }
+ /* FIXME this is probably EBW. */
if (ssh->state == SSH_STATE_CLOSED)
return;
}
+ /* We're out of data. Go and get some more. */
crReturnV;
}
crFinishV;
Ssh ssh = (Ssh) plug;
int need_notify = ssh_do_close(ssh, FALSE);
- if (!error_msg && !ssh->close_expected) {
- error_msg = "Server unexpectedly closed network connection";
+ if (!error_msg) {
+ if (!ssh->close_expected)
+ error_msg = "Server unexpectedly closed network connection";
+ else
+ error_msg = "Server closed network connection";
}
+ if (ssh->close_expected && ssh->clean_exit && ssh->exitcode < 0)
+ ssh->exitcode = 0;
+
if (need_notify)
notify_remote_exit(ssh->frontend);
- if (error_msg) {
- /* A socket error has occurred. */
+ if (error_msg)
logevent(error_msg);
+ if (!ssh->close_expected || !ssh->clean_exit)
connection_fatal(ssh->frontend, "%s", error_msg);
- } else {
- logevent("Server closed network connection");
- }
return 0;
}
const char *err;
ssh->savedhost = snewn(1 + strlen(host), char);
- if (!ssh->savedhost)
- fatalbox("Out of memory");
strcpy(ssh->savedhost, host);
if (port < 0)
return err;
}
+ /*
+ * If the SSH version number's fixed, set it now, and if it's SSH-2,
+ * send the version string too.
+ */
+ if (ssh->cfg.sshprot == 0)
+ ssh->version = 1;
+ if (ssh->cfg.sshprot == 3) {
+ ssh->version = 2;
+ ssh_send_verstring(ssh, NULL);
+ }
+
return NULL;
}
}
}
-/*
- * Username and password input, abstracted off into routines
- * reusable in several places - even between SSH-1 and SSH-2.
- */
-
-/* Set up a username or password input loop on a given buffer. */
-static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
-{
- ssh->userpass_input_buffer = buffer;
- ssh->userpass_input_buflen = buflen;
- ssh->userpass_input_bufpos = 0;
- ssh->userpass_input_echo = echo;
-}
-
-/*
- * Process some terminal data in the course of username/password
- * input. Returns >0 for success (line of input returned in
- * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
- * for inconclusive (keep waiting for more input please).
- */
-static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
-{
- char c;
-
- while (inlen--) {
- switch (c = *in++) {
- case 10:
- case 13:
- ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
- ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
- return +1;
- break;
- case 8:
- case 127:
- if (ssh->userpass_input_bufpos > 0) {
- if (ssh->userpass_input_echo)
- c_write_str(ssh, "\b \b");
- ssh->userpass_input_bufpos--;
- }
- break;
- case 21:
- case 27:
- while (ssh->userpass_input_bufpos > 0) {
- if (ssh->userpass_input_echo)
- c_write_str(ssh, "\b \b");
- ssh->userpass_input_bufpos--;
- }
- break;
- case 3:
- case 4:
- return -1;
- break;
- default:
- /*
- * This simplistic check for printability is disabled
- * when we're doing password input, because some people
- * have control characters in their passwords.o
- */
- if ((!ssh->userpass_input_echo ||
- (c >= ' ' && c <= '~') ||
- ((unsigned char) c >= 160))
- && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
- ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
- if (ssh->userpass_input_echo)
- c_write(ssh, &c, 1);
- }
- break;
- }
- }
- return 0;
-}
-
static void ssh_agent_callback(void *sshv, void *reply, int replylen)
{
Ssh ssh = (Ssh) sshv;
} else {
send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
PKT_INT, c->remoteid,
- PKTT_DATA,
PKT_INT, replylen,
+ PKTT_DATA,
PKT_DATA, sentreply, replylen,
PKTT_OTHER,
PKT_END);
}
/*
+ * Client-initiated disconnection. Send a DISCONNECT if `wire_reason'
+ * non-NULL, otherwise just close the connection. `client_reason' == NULL
+ * => log `wire_reason'.
+ */
+static void ssh_disconnect(Ssh ssh, char *client_reason, char *wire_reason,
+ int code, int clean_exit)
+{
+ char *error;
+ if (!client_reason)
+ client_reason = wire_reason;
+ if (client_reason)
+ error = dupprintf("Disconnected: %s", client_reason);
+ else
+ error = dupstr("Disconnected");
+ if (wire_reason) {
+ if (ssh->version == 1) {
+ send_packet(ssh, SSH1_MSG_DISCONNECT, PKT_STR, wire_reason,
+ PKT_END);
+ } else if (ssh->version == 2) {
+ struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(pktout, code);
+ ssh2_pkt_addstring(pktout, wire_reason);
+ ssh2_pkt_addstring(pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, pktout);
+ }
+ }
+ ssh->close_expected = TRUE;
+ ssh->clean_exit = clean_exit;
+ ssh_closing((Plug)ssh, error, 0, 0);
+ sfree(error);
+}
+
+/*
* Handle the key exchange and user authentication phases.
*/
static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
char username[100];
void *publickey_blob;
int publickey_bloblen;
- char password[100];
- char prompt[200];
- int pos;
+ char *publickey_comment;
+ int publickey_encrypted;
+ prompts_t *cur_prompt;
char c;
int pwpkt_type;
unsigned char request[5], *response, *p;
s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
s->rsabuf = snewn(s->len, unsigned char);
- if (!s->rsabuf)
- fatalbox("Out of memory");
/*
* Verify the host key.
int len = rsastr_len(&hostkey);
char fingerprint[100];
char *keystr = snewn(len, char);
- if (!keystr)
- fatalbox("Out of memory");
rsastr_fmt(keystr, &hostkey);
rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at host key verification",
+ NULL, 0, TRUE);
crStop(0);
}
}
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
crStop(0);
}
}
logevent("Successfully started encryption");
- fflush(stdout);
+ fflush(stdout); /* FIXME eh? */
{
if (!*ssh->cfg.username) {
- if (ssh_get_line && !ssh_getline_pw_only) {
- if (!ssh_get_line("login as: ",
- s->username, sizeof(s->username), FALSE)) {
- /*
- * get_line failed to get a username.
- * Terminate.
- */
- logevent("No username provided. Abandoning session.");
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStop(1);
- }
- } else {
- int ret; /* need not be kept over crReturn */
- c_write_str(ssh, "login as: ");
+ int ret; /* need not be kept over crReturn */
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH login name");
+ add_prompt(s->cur_prompt, dupstr("login as: "), TRUE,
+ lenof(s->username));
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
ssh->send_ok = 1;
-
- setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
- do {
- crWaitUntil(!pktin);
- ret = process_userpass_input(ssh, in, inlen);
- } while (ret == 0);
- if (ret < 0)
- cleanup_exit(0);
- c_write_str(ssh, "\r\n");
+ crWaitUntil(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /*
+ * Failed to get a username. Terminate.
+ */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, "No username provided", NULL, 0, TRUE);
+ crStop(0);
}
+ memcpy(s->username, s->cur_prompt->prompts[0]->result,
+ lenof(s->username));
+ free_prompts(s->cur_prompt);
} else {
strncpy(s->username, ssh->cfg.username, sizeof(s->username));
s->username[sizeof(s->username)-1] = '\0';
send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
{
- char userlog[22 + sizeof(s->username)];
- sprintf(userlog, "Sent username \"%s\"", s->username);
+ char *userlog = dupprintf("Sent username \"%s\"", s->username);
logevent(userlog);
if (flags & FLAG_INTERACTIVE &&
(!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
- strcat(userlog, "\r\n");
c_write_str(ssh, userlog);
+ c_write_str(ssh, "\r\n");
}
+ sfree(userlog);
}
}
s->tried_publickey = s->tried_agent = 0;
}
s->tis_auth_refused = s->ccard_auth_refused = 0;
- /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
+ /*
+ * Load the public half of any configured keyfile for later use.
+ */
if (!filename_is_null(ssh->cfg.keyfile)) {
- if (!rsakey_pubblob(&ssh->cfg.keyfile,
- &s->publickey_blob, &s->publickey_bloblen, NULL))
+ int keytype;
+ logeventf(ssh, "Reading private key file \"%.150s\"",
+ filename_to_str(&ssh->cfg.keyfile));
+ keytype = key_type(&ssh->cfg.keyfile);
+ if (keytype == SSH_KEYTYPE_SSH1) {
+ const char *error;
+ if (rsakey_pubblob(&ssh->cfg.keyfile,
+ &s->publickey_blob, &s->publickey_bloblen,
+ &s->publickey_comment, &error)) {
+ s->publickey_encrypted = rsakey_encrypted(&ssh->cfg.keyfile,
+ NULL);
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to load private key (%s)", error);
+ msgbuf = dupprintf("Unable to load private key file "
+ "\"%.150s\" (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ error);
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
+ s->publickey_blob = NULL;
+ }
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to use this key file (%s)",
+ key_type_to_str(keytype));
+ msgbuf = dupprintf("Unable to use key file \"%.150s\""
+ " (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ key_type_to_str(keytype));
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
s->publickey_blob = NULL;
+ }
} else
s->publickey_blob = NULL;
while (pktin->type == SSH1_SMSG_FAILURE) {
s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
- if (agent_exists() && !s->tried_agent) {
+ if (ssh->cfg.tryagent && agent_exists() && !s->tried_agent) {
/*
* Attempt RSA authentication using Pageant.
*/
s->p += 4;
logeventf(ssh, "Pageant has %d SSH-1 keys", s->nkeys);
for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
- logeventf(ssh, "Trying Pageant key #%d", s->keyi);
- if (s->publickey_blob &&
- !memcmp(s->p, s->publickey_blob,
- s->publickey_bloblen)) {
- logevent("This key matches configured key file");
- s->tried_publickey = 1;
- }
+ unsigned char *pkblob = s->p;
s->p += 4;
{
int n, ok = FALSE;
break;
}
}
+ if (s->publickey_blob) {
+ if (!memcmp(pkblob, s->publickey_blob,
+ s->publickey_bloblen)) {
+ logeventf(ssh, "Pageant key #%d matches "
+ "configured key file", s->keyi);
+ s->tried_publickey = 1;
+ } else
+ /* Skip non-configured key */
+ continue;
+ }
+ logeventf(ssh, "Trying Pageant key #%d", s->keyi);
send_packet(ssh, SSH1_CMSG_AUTH_RSA,
PKT_BIGNUM, s->key.modulus, PKT_END);
crWaitUntil(pktin);
break;
}
sfree(s->response);
+ if (s->publickey_blob && !s->tried_publickey)
+ logevent("Configured key file not in Pageant");
}
if (s->authed)
break;
}
- if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
- s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
+ if (s->publickey_blob && !s->tried_publickey) {
+ /*
+ * Try public key authentication with the specified
+ * key file.
+ */
+ int got_passphrase; /* need not be kept over crReturn */
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "Trying public key authentication.\r\n");
+ logeventf(ssh, "Trying public key \"%s\"",
+ filename_to_str(&ssh->cfg.keyfile));
+ s->tried_publickey = 1;
+ got_passphrase = FALSE;
+ while (!got_passphrase) {
+ /*
+ * Get a passphrase, if necessary.
+ */
+ char *passphrase = NULL; /* only written after crReturn */
+ const char *error;
+ if (!s->publickey_encrypted) {
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "No passphrase required.\r\n");
+ passphrase = NULL;
+ } else {
+ int ret; /* need not be kept over crReturn */
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = FALSE;
+ s->cur_prompt->name = dupstr("SSH key passphrase");
+ add_prompt(s->cur_prompt,
+ dupprintf("Passphrase for key \"%.100s\": ",
+ s->publickey_comment),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntil(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /* Failed to get a passphrase. Terminate. */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate",
+ 0, TRUE);
+ crStop(0);
+ }
+ passphrase = dupstr(s->cur_prompt->prompts[0]->result);
+ free_prompts(s->cur_prompt);
+ }
+ /*
+ * Try decrypting key with passphrase.
+ */
+ ret = loadrsakey(&ssh->cfg.keyfile, &s->key, passphrase,
+ &error);
+ if (passphrase) {
+ memset(passphrase, 0, strlen(passphrase));
+ sfree(passphrase);
+ }
+ if (ret == 1) {
+ /* Correct passphrase. */
+ got_passphrase = TRUE;
+ } else if (ret == 0) {
+ c_write_str(ssh, "Couldn't load private key from ");
+ c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
+ c_write_str(ssh, " (");
+ c_write_str(ssh, error);
+ c_write_str(ssh, ").\r\n");
+ got_passphrase = FALSE;
+ break; /* go and try something else */
+ } else if (ret == -1) {
+ c_write_str(ssh, "Wrong passphrase.\r\n"); /* FIXME */
+ got_passphrase = FALSE;
+ /* and try again */
+ } else {
+ assert(0 && "unexpected return from loadrsakey()");
+ got_passphrase = FALSE; /* placate optimisers */
+ }
+ }
- if (ssh->cfg.try_tis_auth &&
- (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
- !s->tis_auth_refused) {
- s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
- logevent("Requested TIS authentication");
- send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
- crWaitUntil(pktin);
- if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
- logevent("TIS authentication declined");
- if (flags & FLAG_INTERACTIVE)
- c_write_str(ssh, "TIS authentication refused.\r\n");
- s->tis_auth_refused = 1;
- continue;
- } else {
- char *challenge;
- int challengelen;
+ if (got_passphrase) {
- ssh_pkt_getstring(pktin, &challenge, &challengelen);
+ /*
+ * Send a public key attempt.
+ */
+ send_packet(ssh, SSH1_CMSG_AUTH_RSA,
+ PKT_BIGNUM, s->key.modulus, PKT_END);
+
+ crWaitUntil(pktin);
+ if (pktin->type == SSH1_SMSG_FAILURE) {
+ c_write_str(ssh, "Server refused our public key.\r\n");
+ continue; /* go and try something else */
+ }
+ if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
+ bombout(("Bizarre response to offer of public key"));
+ crStop(0);
+ }
+
+ {
+ int i;
+ unsigned char buffer[32];
+ Bignum challenge, response;
+
+ if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
+ bombout(("Server's RSA challenge was badly formatted"));
+ crStop(0);
+ }
+ response = rsadecrypt(challenge, &s->key);
+ freebn(s->key.private_exponent);/* burn the evidence */
+
+ for (i = 0; i < 32; i++) {
+ buffer[i] = bignum_byte(response, 31 - i);
+ }
+
+ MD5Init(&md5c);
+ MD5Update(&md5c, buffer, 32);
+ MD5Update(&md5c, s->session_id, 16);
+ MD5Final(buffer, &md5c);
+
+ send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
+ PKT_DATA, buffer, 16, PKT_END);
+
+ freebn(challenge);
+ freebn(response);
+ }
+
+ crWaitUntil(pktin);
+ if (pktin->type == SSH1_SMSG_FAILURE) {
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "Failed to authenticate with"
+ " our public key.\r\n");
+ continue; /* go and try something else */
+ } else if (pktin->type != SSH1_SMSG_SUCCESS) {
+ bombout(("Bizarre response to RSA authentication response"));
+ crStop(0);
+ }
+
+ break; /* we're through! */
+ }
+
+ }
+
+ /*
+ * Otherwise, try various forms of password-like authentication.
+ */
+ s->cur_prompt = new_prompts(ssh->frontend);
+
+ if (ssh->cfg.try_tis_auth &&
+ (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
+ !s->tis_auth_refused) {
+ s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
+ logevent("Requested TIS authentication");
+ send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
+ crWaitUntil(pktin);
+ if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
+ logevent("TIS authentication declined");
+ if (flags & FLAG_INTERACTIVE)
+ c_write_str(ssh, "TIS authentication refused.\r\n");
+ s->tis_auth_refused = 1;
+ continue;
+ } else {
+ char *challenge;
+ int challengelen;
+ char *instr_suf, *prompt;
+
+ ssh_pkt_getstring(pktin, &challenge, &challengelen);
if (!challenge) {
bombout(("TIS challenge packet was badly formed"));
crStop(0);
}
- c_write_str(ssh, "Using TIS authentication.\r\n");
logevent("Received TIS challenge");
- if (challengelen > sizeof(s->prompt) - 1)
- challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
- memcpy(s->prompt, challenge, challengelen);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH TIS authentication");
/* Prompt heuristic comes from OpenSSH */
- strncpy(s->prompt + challengelen,
- memchr(s->prompt, '\n', challengelen) ?
- "": "\r\nResponse: ",
- (sizeof s->prompt) - challengelen);
- s->prompt[(sizeof s->prompt) - 1] = '\0';
+ if (memchr(challenge, '\n', challengelen)) {
+ instr_suf = dupstr("");
+ prompt = dupprintf("%.*s", challengelen, challenge);
+ } else {
+ instr_suf = dupprintf("%.*s", challengelen, challenge);
+ prompt = dupstr("Response: ");
+ }
+ s->cur_prompt->instruction =
+ dupprintf("Using TIS authentication.%s%s",
+ (*instr_suf) ? "\n" : "",
+ instr_suf);
+ s->cur_prompt->instr_reqd = TRUE;
+ add_prompt(s->cur_prompt, prompt, FALSE, SSH_MAX_PASSWORD_LEN);
+ sfree(instr_suf);
}
}
if (ssh->cfg.try_tis_auth &&
} else {
char *challenge;
int challengelen;
+ char *instr_suf, *prompt;
ssh_pkt_getstring(pktin, &challenge, &challengelen);
if (!challenge) {
bombout(("CryptoCard challenge packet was badly formed"));
crStop(0);
}
- c_write_str(ssh, "Using CryptoCard authentication.\r\n");
logevent("Received CryptoCard challenge");
- if (challengelen > sizeof(s->prompt) - 1)
- challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
- memcpy(s->prompt, challenge, challengelen);
- strncpy(s->prompt + challengelen,
- memchr(s->prompt, '\n', challengelen) ?
- "" : "\r\nResponse: ",
- sizeof(s->prompt) - challengelen);
- s->prompt[sizeof(s->prompt) - 1] = '\0';
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH CryptoCard authentication");
+ s->cur_prompt->name_reqd = FALSE;
+ /* Prompt heuristic comes from OpenSSH */
+ if (memchr(challenge, '\n', challengelen)) {
+ instr_suf = dupstr("");
+ prompt = dupprintf("%.*s", challengelen, challenge);
+ } else {
+ instr_suf = dupprintf("%.*s", challengelen, challenge);
+ prompt = dupstr("Response: ");
+ }
+ s->cur_prompt->instruction =
+ dupprintf("Using CryptoCard authentication.%s%s",
+ (*instr_suf) ? "\n" : "",
+ instr_suf);
+ s->cur_prompt->instr_reqd = TRUE;
+ add_prompt(s->cur_prompt, prompt, FALSE, SSH_MAX_PASSWORD_LEN);
+ sfree(instr_suf);
}
}
if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
- sprintf(s->prompt, "%.90s@%.90s's password: ",
- s->username, ssh->savedhost);
- }
- if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
- char *comment = NULL;
- int type;
- if (flags & FLAG_VERBOSE)
- c_write_str(ssh, "Trying public key authentication.\r\n");
- logeventf(ssh, "Trying public key \"%s\"",
- filename_to_str(&ssh->cfg.keyfile));
- type = key_type(&ssh->cfg.keyfile);
- if (type != SSH_KEYTYPE_SSH1) {
- char *msg = dupprintf("Key is of wrong type (%s)",
- key_type_to_str(type));
- logevent(msg);
- c_write_str(ssh, msg);
- c_write_str(ssh, "\r\n");
- sfree(msg);
- s->tried_publickey = 1;
- continue;
- }
- if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
- if (flags & FLAG_VERBOSE)
- c_write_str(ssh, "No passphrase required.\r\n");
- goto tryauth;
- }
- sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
- sfree(comment);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH password");
+ add_prompt(s->cur_prompt, dupprintf("%.90s@%.90s's password: ",
+ s->username, ssh->savedhost),
+ FALSE, SSH_MAX_PASSWORD_LEN);
}
/*
* or CryptoCard exchange if we're doing TIS or CryptoCard
* authentication.
*/
- if (ssh_get_line) {
- if (!ssh_get_line(s->prompt, s->password,
- sizeof(s->password), TRUE)) {
+ {
+ int ret; /* need not be kept over crReturn */
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntil(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
/*
- * get_line failed to get a password (for example
+ * Failed to get a password (for example
* because one was supplied on the command line
* which has already failed to work). Terminate.
*/
- send_packet(ssh, SSH1_MSG_DISCONNECT,
- PKT_STR, "No more passwords available to try",
- PKT_END);
- logevent("Unable to authenticate");
- connection_fatal(ssh->frontend, "Unable to authenticate");
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStop(1);
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate", 0, TRUE);
+ crStop(0);
}
- } else {
- /* Prompt may have come from server. We've munged it a bit, so
- * we know it to be zero-terminated at least once. */
- int ret; /* need not be saved over crReturn */
- c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
- s->pos = 0;
-
- setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
- do {
- crWaitUntil(!pktin);
- ret = process_userpass_input(ssh, in, inlen);
- } while (ret == 0);
- if (ret < 0)
- cleanup_exit(0);
- c_write_str(ssh, "\r\n");
}
- tryauth:
- if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
- /*
- * Try public key authentication with the specified
- * key file.
- */
- s->tried_publickey = 1;
-
- {
- const char *error = NULL;
- int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
- &error);
- if (ret == 0) {
- c_write_str(ssh, "Couldn't load private key from ");
- c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
- c_write_str(ssh, " (");
- c_write_str(ssh, error);
- c_write_str(ssh, ").\r\n");
- continue; /* go and try password */
- }
- if (ret == -1) {
- c_write_str(ssh, "Wrong passphrase.\r\n");
- s->tried_publickey = 0;
- continue; /* try again */
- }
- }
-
+ if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
/*
- * Send a public key attempt.
+ * Defence against traffic analysis: we send a
+ * whole bunch of packets containing strings of
+ * different lengths. One of these strings is the
+ * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
+ * The others are all random data in
+ * SSH1_MSG_IGNORE packets. This way a passive
+ * listener can't tell which is the password, and
+ * hence can't deduce the password length.
+ *
+ * Anybody with a password length greater than 16
+ * bytes is going to have enough entropy in their
+ * password that a listener won't find it _that_
+ * much help to know how long it is. So what we'll
+ * do is:
+ *
+ * - if password length < 16, we send 15 packets
+ * containing string lengths 1 through 15
+ *
+ * - otherwise, we let N be the nearest multiple
+ * of 8 below the password length, and send 8
+ * packets containing string lengths N through
+ * N+7. This won't obscure the order of
+ * magnitude of the password length, but it will
+ * introduce a bit of extra uncertainty.
+ *
+ * A few servers can't deal with SSH1_MSG_IGNORE, at
+ * least in this context. For these servers, we need
+ * an alternative defence. We make use of the fact
+ * that the password is interpreted as a C string:
+ * so we can append a NUL, then some random data.
+ *
+ * A few servers can deal with neither SSH1_MSG_IGNORE
+ * here _nor_ a padded password string.
+ * For these servers we are left with no defences
+ * against password length sniffing.
*/
- send_packet(ssh, SSH1_CMSG_AUTH_RSA,
- PKT_BIGNUM, s->key.modulus, PKT_END);
-
- crWaitUntil(pktin);
- if (pktin->type == SSH1_SMSG_FAILURE) {
- c_write_str(ssh, "Server refused our public key.\r\n");
- continue; /* go and try password */
- }
- if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
- bombout(("Bizarre response to offer of public key"));
- crStop(0);
- }
-
- {
- int i;
- unsigned char buffer[32];
- Bignum challenge, response;
-
- if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
- bombout(("Server's RSA challenge was badly formatted"));
- crStop(0);
- }
- response = rsadecrypt(challenge, &s->key);
- freebn(s->key.private_exponent);/* burn the evidence */
-
- for (i = 0; i < 32; i++) {
- buffer[i] = bignum_byte(response, 31 - i);
- }
-
- MD5Init(&md5c);
- MD5Update(&md5c, buffer, 32);
- MD5Update(&md5c, s->session_id, 16);
- MD5Final(buffer, &md5c);
-
- send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
- PKT_DATA, buffer, 16, PKT_END);
-
- freebn(challenge);
- freebn(response);
- }
-
- crWaitUntil(pktin);
- if (pktin->type == SSH1_SMSG_FAILURE) {
- if (flags & FLAG_VERBOSE)
- c_write_str(ssh, "Failed to authenticate with"
- " our public key.\r\n");
- continue; /* go and try password */
- } else if (pktin->type != SSH1_SMSG_SUCCESS) {
- bombout(("Bizarre response to RSA authentication response"));
- crStop(0);
- }
-
- break; /* we're through! */
- } else {
- if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
+ if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE) &&
+ !(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
/*
- * Defence against traffic analysis: we send a
- * whole bunch of packets containing strings of
- * different lengths. One of these strings is the
- * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
- * The others are all random data in
- * SSH1_MSG_IGNORE packets. This way a passive
- * listener can't tell which is the password, and
- * hence can't deduce the password length.
- *
- * Anybody with a password length greater than 16
- * bytes is going to have enough entropy in their
- * password that a listener won't find it _that_
- * much help to know how long it is. So what we'll
- * do is:
- *
- * - if password length < 16, we send 15 packets
- * containing string lengths 1 through 15
- *
- * - otherwise, we let N be the nearest multiple
- * of 8 below the password length, and send 8
- * packets containing string lengths N through
- * N+7. This won't obscure the order of
- * magnitude of the password length, but it will
- * introduce a bit of extra uncertainty.
- *
- * A few servers (the old 1.2.18 through 1.2.22)
- * can't deal with SSH1_MSG_IGNORE. For these
- * servers, we need an alternative defence. We make
- * use of the fact that the password is interpreted
- * as a C string: so we can append a NUL, then some
- * random data.
- *
- * One server (a Cisco one) can deal with neither
- * SSH1_MSG_IGNORE _nor_ a padded password string.
- * For this server we are left with no defences
- * against password length sniffing.
+ * The server can deal with SSH1_MSG_IGNORE, so
+ * we can use the primary defence.
*/
- if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
- /*
- * The server can deal with SSH1_MSG_IGNORE, so
- * we can use the primary defence.
- */
- int bottom, top, pwlen, i;
- char *randomstr;
+ int bottom, top, pwlen, i;
+ char *randomstr;
- pwlen = strlen(s->password);
- if (pwlen < 16) {
- bottom = 0; /* zero length passwords are OK! :-) */
- top = 15;
- } else {
- bottom = pwlen & ~7;
- top = bottom + 7;
- }
+ pwlen = strlen(s->cur_prompt->prompts[0]->result);
+ if (pwlen < 16) {
+ bottom = 0; /* zero length passwords are OK! :-) */
+ top = 15;
+ } else {
+ bottom = pwlen & ~7;
+ top = bottom + 7;
+ }
- assert(pwlen >= bottom && pwlen <= top);
+ assert(pwlen >= bottom && pwlen <= top);
- randomstr = snewn(top + 1, char);
+ randomstr = snewn(top + 1, char);
- for (i = bottom; i <= top; i++) {
- if (i == pwlen) {
- defer_packet(ssh, s->pwpkt_type,
- PKTT_PASSWORD, PKT_STR, s->password,
- PKTT_OTHER, PKT_END);
- } else {
- for (j = 0; j < i; j++) {
- do {
- randomstr[j] = random_byte();
- } while (randomstr[j] == '\0');
- }
- randomstr[i] = '\0';
- defer_packet(ssh, SSH1_MSG_IGNORE,
- PKT_STR, randomstr, PKT_END);
+ for (i = bottom; i <= top; i++) {
+ if (i == pwlen) {
+ defer_packet(ssh, s->pwpkt_type,
+ PKTT_PASSWORD, PKT_STR,
+ s->cur_prompt->prompts[0]->result,
+ PKTT_OTHER, PKT_END);
+ } else {
+ for (j = 0; j < i; j++) {
+ do {
+ randomstr[j] = random_byte();
+ } while (randomstr[j] == '\0');
}
+ randomstr[i] = '\0';
+ defer_packet(ssh, SSH1_MSG_IGNORE,
+ PKT_STR, randomstr, PKT_END);
}
- logevent("Sending password with camouflage packets");
- ssh_pkt_defersend(ssh);
- sfree(randomstr);
- }
- else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
- /*
- * The server can't deal with SSH1_MSG_IGNORE
- * but can deal with padded passwords, so we
- * can use the secondary defence.
- */
- char string[64];
- char *ss;
- int len;
-
- len = strlen(s->password);
- if (len < sizeof(string)) {
- ss = string;
- strcpy(string, s->password);
- len++; /* cover the zero byte */
- while (len < sizeof(string)) {
- string[len++] = (char) random_byte();
- }
- } else {
- ss = s->password;
+ }
+ logevent("Sending password with camouflage packets");
+ ssh_pkt_defersend(ssh);
+ sfree(randomstr);
+ }
+ else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
+ /*
+ * The server can't deal with SSH1_MSG_IGNORE
+ * but can deal with padded passwords, so we
+ * can use the secondary defence.
+ */
+ char string[64];
+ char *ss;
+ int len;
+
+ len = strlen(s->cur_prompt->prompts[0]->result);
+ if (len < sizeof(string)) {
+ ss = string;
+ strcpy(string, s->cur_prompt->prompts[0]->result);
+ len++; /* cover the zero byte */
+ while (len < sizeof(string)) {
+ string[len++] = (char) random_byte();
}
- logevent("Sending length-padded password");
- send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
- PKT_INT, len, PKT_DATA, ss, len,
- PKTT_OTHER, PKT_END);
} else {
- /*
- * The server has _both_
- * BUG_CHOKES_ON_SSH1_IGNORE and
- * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
- * therefore nothing we can do.
- */
- int len;
- len = strlen(s->password);
- logevent("Sending unpadded password");
- send_packet(ssh, s->pwpkt_type,
- PKTT_PASSWORD, PKT_INT, len,
- PKT_DATA, s->password, len,
- PKTT_OTHER, PKT_END);
+ ss = s->cur_prompt->prompts[0]->result;
}
- } else {
+ logevent("Sending length-padded password");
send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
- PKT_STR, s->password, PKTT_OTHER, PKT_END);
+ PKT_INT, len, PKT_DATA, ss, len,
+ PKTT_OTHER, PKT_END);
+ } else {
+ /*
+ * The server is believed unable to cope with
+ * any of our password camouflage methods.
+ */
+ int len;
+ len = strlen(s->cur_prompt->prompts[0]->result);
+ logevent("Sending unpadded password");
+ send_packet(ssh, s->pwpkt_type,
+ PKTT_PASSWORD, PKT_INT, len,
+ PKT_DATA, s->cur_prompt->prompts[0]->result, len,
+ PKTT_OTHER, PKT_END);
}
+ } else {
+ send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
+ PKT_STR, s->cur_prompt->prompts[0]->result,
+ PKTT_OTHER, PKT_END);
}
logevent("Sent password");
- memset(s->password, 0, strlen(s->password));
+ free_prompts(s->cur_prompt);
crWaitUntil(pktin);
if (pktin->type == SSH1_SMSG_FAILURE) {
if (flags & FLAG_VERBOSE)
}
}
+ /* Clear up */
+ if (s->publickey_blob) {
+ sfree(s->publickey_blob);
+ sfree(s->publickey_comment);
+ }
+
logevent("Authentication successful");
crFinish(1);
if (ssh->version == 1) {
send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
PKT_INT, c->remoteid,
- PKTT_DATA,
- PKT_INT, len, PKT_DATA, buf, len,
+ PKT_INT, len, PKTT_DATA, PKT_DATA, buf, len,
PKTT_OTHER, PKT_END);
/*
* In SSH-1 we can return 0 here - implying that forwarded
/* Data for an agent message. Buffer it. */
while (len > 0) {
if (c->u.a.lensofar < 4) {
- unsigned int l = min(4 - c->u.a.lensofar, len);
+ unsigned int l = min(4 - c->u.a.lensofar, (unsigned)len);
memcpy(c->u.a.msglen + c->u.a.lensofar, p,
l);
p += l;
if (c->u.a.lensofar >= 4 && len > 0) {
unsigned int l =
min(c->u.a.totallen - c->u.a.lensofar,
- len);
+ (unsigned)len);
memcpy(c->u.a.message + c->u.a.lensofar, p,
l);
p += l;
* encrypted packet, we close the session once
* we've sent EXIT_CONFIRMATION.
*/
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, NULL, NULL, 0, TRUE);
}
/* Helper function to deal with sending tty modes for REQUEST_PTY */
} else {
while (inlen > 0) {
int len = min(inlen, 512);
- send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
- PKT_INT, len, PKT_DATA, in, len,
+ send_packet(ssh, SSH1_CMSG_STDIN_DATA,
+ PKT_INT, len, PKTT_DATA, PKT_DATA, in, len,
PKTT_OTHER, PKT_END);
in += len;
inlen -= len;
/*
* SSH-2 key creation method.
+ * (Currently assumes 2 lots of any hash are sufficient to generate
+ * keys/IVs for any cipher/MAC. SSH2_MKKEY_ITERS documents this assumption.)
*/
-static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
- unsigned char *sessid, char chr,
+#define SSH2_MKKEY_ITERS (2)
+static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H, char chr,
unsigned char *keyspace)
{
- SHA_State s;
- /* First 20 bytes. */
- SHA_Init(&s);
+ const struct ssh_hash *h = ssh->kex->hash;
+ void *s;
+ /* First hlen bytes. */
+ s = h->init();
if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
- sha_mpint(&s, K);
- SHA_Bytes(&s, H, 20);
- SHA_Bytes(&s, &chr, 1);
- SHA_Bytes(&s, sessid, 20);
- SHA_Final(&s, keyspace);
- /* Next 20 bytes. */
- SHA_Init(&s);
+ hash_mpint(h, s, K);
+ h->bytes(s, H, h->hlen);
+ h->bytes(s, &chr, 1);
+ h->bytes(s, ssh->v2_session_id, ssh->v2_session_id_len);
+ h->final(s, keyspace);
+ /* Next hlen bytes. */
+ s = h->init();
if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
- sha_mpint(&s, K);
- SHA_Bytes(&s, H, 20);
- SHA_Bytes(&s, keyspace, 20);
- SHA_Final(&s, keyspace + 20);
+ hash_mpint(h, s, K);
+ h->bytes(s, H, h->hlen);
+ h->bytes(s, keyspace, h->hlen);
+ h->final(s, keyspace + h->hlen);
}
/*
struct do_ssh2_transport_state {
int nbits, pbits, warn_kex, warn_cscipher, warn_sccipher;
Bignum p, g, e, f, K;
+ void *our_kexinit;
+ int our_kexinitlen;
int kex_init_value, kex_reply_value;
const struct ssh_mac **maclist;
int nmacs;
const struct ssh_mac *scmac_tobe;
const struct ssh_compress *cscomp_tobe;
const struct ssh_compress *sccomp_tobe;
- char *hostkeydata, *sigdata, *keystr, *fingerprint;
- int hostkeylen, siglen;
+ char *hostkeydata, *sigdata, *rsakeydata, *keystr, *fingerprint;
+ int hostkeylen, siglen, rsakeylen;
void *hkey; /* actual host key */
- unsigned char exchange_hash[20];
+ void *rsakey; /* for RSA kex */
+ unsigned char exchange_hash[SSH2_KEX_MAX_HASH_LEN];
int n_preferred_kex;
- const struct ssh_kex *preferred_kex[KEX_MAX];
+ const struct ssh_kexes *preferred_kex[KEX_MAX];
int n_preferred_ciphers;
const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
const struct ssh_compress *preferred_comp;
s->maclist = macs, s->nmacs = lenof(macs);
begin_key_exchange:
- ssh->pkt_ctx &= ~SSH2_PKTCTX_KEX_MASK;
+ ssh->pkt_kctx = SSH2_PKTCTX_NOKEX;
{
int i, j, commalist_started;
s->preferred_kex[s->n_preferred_kex++] =
&ssh_diffiehellman_group1;
break;
- case CIPHER_WARN:
+ case KEX_RSA:
+ s->preferred_kex[s->n_preferred_kex++] =
+ &ssh_rsa_kex;
+ break;
+ case KEX_WARN:
/* Flag for later. Don't bother if it's the last in
* the list. */
if (i < KEX_MAX - 1) {
ssh2_pkt_addstring_start(s->pktout);
commalist_started = 0;
for (i = 0; i < s->n_preferred_kex; i++) {
- const struct ssh_kex *k = s->preferred_kex[i];
+ const struct ssh_kexes *k = s->preferred_kex[i];
if (!k) continue; /* warning flag */
- if (commalist_started)
- ssh2_pkt_addstring_str(s->pktout, ",");
- ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->name);
- commalist_started = 1;
+ for (j = 0; j < k->nkexes; j++) {
+ if (commalist_started)
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ ssh2_pkt_addstring_str(s->pktout, k->list[j]->name);
+ commalist_started = 1;
+ }
}
/* List server host key algorithms. */
ssh2_pkt_addstring_start(s->pktout);
ssh2_pkt_adduint32(s->pktout, 0);
}
- ssh->exhash = ssh->exhashbase;
- sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
+ s->our_kexinitlen = s->pktout->length - 5;
+ s->our_kexinit = snewn(s->our_kexinitlen, unsigned char);
+ memcpy(s->our_kexinit, s->pktout->data + 5, s->our_kexinitlen);
ssh2_pkt_send_noqueue(ssh, s->pktout);
if (!pktin)
crWaitUntil(pktin);
- if (pktin->length > 5)
- sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
/*
* Now examine the other side's KEXINIT to see what we're up
preferred = NULL;
for (i = 0; i < s->n_preferred_kex; i++) {
- const struct ssh_kex *k = s->preferred_kex[i];
+ const struct ssh_kexes *k = s->preferred_kex[i];
if (!k) {
s->warn_kex = TRUE;
} else {
- if (!preferred) preferred = k->name;
- if (in_commasep_string(k->name, str, len))
- ssh->kex = k;
+ for (j = 0; j < k->nkexes; j++) {
+ if (!preferred) preferred = k->list[j]->name;
+ if (in_commasep_string(k->list[j]->name, str, len)) {
+ ssh->kex = k->list[j];
+ break;
+ }
+ }
}
if (ssh->kex)
break;
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at kex warning", NULL,
+ 0, TRUE);
crStop(0);
}
}
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
crStop(0);
}
}
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
crStop(0);
}
}
+ ssh->exhash = ssh->kex->hash->init();
+ hash_string(ssh->kex->hash, ssh->exhash, ssh->v_c, strlen(ssh->v_c));
+ hash_string(ssh->kex->hash, ssh->exhash, ssh->v_s, strlen(ssh->v_s));
+ hash_string(ssh->kex->hash, ssh->exhash,
+ s->our_kexinit, s->our_kexinitlen);
+ sfree(s->our_kexinit);
+ if (pktin->length > 5)
+ hash_string(ssh->kex->hash, ssh->exhash,
+ pktin->data + 5, pktin->length - 5);
+
if (s->ignorepkt) /* first_kex_packet_follows */
crWaitUntil(pktin); /* Ignore packet */
}
- /*
- * Work out the number of bits of key we will need from the key
- * exchange. We start with the maximum key length of either
- * cipher...
- */
- {
- int csbits, scbits;
+ if (ssh->kex->main_type == KEXTYPE_DH) {
+ /*
+ * Work out the number of bits of key we will need from the
+ * key exchange. We start with the maximum key length of
+ * either cipher...
+ */
+ {
+ int csbits, scbits;
- csbits = s->cscipher_tobe->keylen;
- scbits = s->sccipher_tobe->keylen;
- s->nbits = (csbits > scbits ? csbits : scbits);
- }
- /* The keys only have 160-bit entropy, since they're based on
- * a SHA-1 hash. So cap the key size at 160 bits. */
- if (s->nbits > 160)
- s->nbits = 160;
+ csbits = s->cscipher_tobe->keylen;
+ scbits = s->sccipher_tobe->keylen;
+ s->nbits = (csbits > scbits ? csbits : scbits);
+ }
+ /* The keys only have hlen-bit entropy, since they're based on
+ * a hash. So cap the key size at hlen bits. */
+ if (s->nbits > ssh->kex->hash->hlen * 8)
+ s->nbits = ssh->kex->hash->hlen * 8;
- /*
- * If we're doing Diffie-Hellman group exchange, start by
- * requesting a group.
- */
- if (!ssh->kex->pdata) {
- logevent("Doing Diffie-Hellman group exchange");
- ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
- /*
- * Work out how big a DH group we will need to allow that
- * much data.
- */
- s->pbits = 512 << ((s->nbits - 1) / 64);
- s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
- ssh2_pkt_adduint32(s->pktout, s->pbits);
- ssh2_pkt_send_noqueue(ssh, s->pktout);
+ /*
+ * If we're doing Diffie-Hellman group exchange, start by
+ * requesting a group.
+ */
+ if (!ssh->kex->pdata) {
+ logevent("Doing Diffie-Hellman group exchange");
+ ssh->pkt_kctx = SSH2_PKTCTX_DHGEX;
+ /*
+ * Work out how big a DH group we will need to allow that
+ * much data.
+ */
+ s->pbits = 512 << ((s->nbits - 1) / 64);
+ s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
+ ssh2_pkt_adduint32(s->pktout, s->pbits);
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+
+ crWaitUntil(pktin);
+ if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
+ bombout(("expected key exchange group packet from server"));
+ crStop(0);
+ }
+ s->p = ssh2_pkt_getmp(pktin);
+ s->g = ssh2_pkt_getmp(pktin);
+ if (!s->p || !s->g) {
+ bombout(("unable to read mp-ints from incoming group packet"));
+ crStop(0);
+ }
+ ssh->kex_ctx = dh_setup_gex(s->p, s->g);
+ s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
+ s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
+ } else {
+ ssh->pkt_kctx = SSH2_PKTCTX_DHGROUP;
+ ssh->kex_ctx = dh_setup_group(ssh->kex);
+ s->kex_init_value = SSH2_MSG_KEXDH_INIT;
+ s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
+ logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
+ ssh->kex->groupname);
+ }
- crWaitUntil(pktin);
- if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
- bombout(("expected key exchange group packet from server"));
- crStop(0);
- }
- s->p = ssh2_pkt_getmp(pktin);
- s->g = ssh2_pkt_getmp(pktin);
- if (!s->p || !s->g) {
- bombout(("unable to read mp-ints from incoming group packet"));
- crStop(0);
- }
- ssh->kex_ctx = dh_setup_gex(s->p, s->g);
- s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
- s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
+ logeventf(ssh, "Doing Diffie-Hellman key exchange with hash %s",
+ ssh->kex->hash->text_name);
+ /*
+ * Now generate and send e for Diffie-Hellman.
+ */
+ set_busy_status(ssh->frontend, BUSY_CPU); /* this can take a while */
+ s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
+ s->pktout = ssh2_pkt_init(s->kex_init_value);
+ ssh2_pkt_addmp(s->pktout, s->e);
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+
+ set_busy_status(ssh->frontend, BUSY_WAITING); /* wait for server */
+ crWaitUntil(pktin);
+ if (pktin->type != s->kex_reply_value) {
+ bombout(("expected key exchange reply packet from server"));
+ crStop(0);
+ }
+ set_busy_status(ssh->frontend, BUSY_CPU); /* cogitate */
+ ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
+ s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
+ s->f = ssh2_pkt_getmp(pktin);
+ if (!s->f) {
+ bombout(("unable to parse key exchange reply packet"));
+ crStop(0);
+ }
+ ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
+
+ s->K = dh_find_K(ssh->kex_ctx, s->f);
+
+ /* We assume everything from now on will be quick, and it might
+ * involve user interaction. */
+ set_busy_status(ssh->frontend, BUSY_NOT);
+
+ hash_string(ssh->kex->hash, ssh->exhash, s->hostkeydata, s->hostkeylen);
+ if (!ssh->kex->pdata) {
+ hash_uint32(ssh->kex->hash, ssh->exhash, s->pbits);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->p);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->g);
+ }
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->e);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->f);
+
+ dh_cleanup(ssh->kex_ctx);
+ freebn(s->f);
+ if (!ssh->kex->pdata) {
+ freebn(s->g);
+ freebn(s->p);
+ }
} else {
- ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
- ssh->kex_ctx = dh_setup_group(ssh->kex);
- s->kex_init_value = SSH2_MSG_KEXDH_INIT;
- s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
- logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
- ssh->kex->groupname);
- }
+ logeventf(ssh, "Doing RSA key exchange with hash %s",
+ ssh->kex->hash->text_name);
+ ssh->pkt_kctx = SSH2_PKTCTX_RSAKEX;
+ /*
+ * RSA key exchange. First expect a KEXRSA_PUBKEY packet
+ * from the server.
+ */
+ crWaitUntil(pktin);
+ if (pktin->type != SSH2_MSG_KEXRSA_PUBKEY) {
+ bombout(("expected RSA public key packet from server"));
+ crStop(0);
+ }
- logevent("Doing Diffie-Hellman key exchange");
- /*
- * Now generate and send e for Diffie-Hellman.
- */
- set_busy_status(ssh->frontend, BUSY_CPU); /* this can take a while */
- s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
- s->pktout = ssh2_pkt_init(s->kex_init_value);
- ssh2_pkt_addmp(s->pktout, s->e);
- ssh2_pkt_send_noqueue(ssh, s->pktout);
+ ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
+ hash_string(ssh->kex->hash, ssh->exhash,
+ s->hostkeydata, s->hostkeylen);
+ s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
- set_busy_status(ssh->frontend, BUSY_WAITING); /* wait for server */
- crWaitUntil(pktin);
- if (pktin->type != s->kex_reply_value) {
- bombout(("expected key exchange reply packet from server"));
- crStop(0);
- }
- set_busy_status(ssh->frontend, BUSY_CPU); /* cogitate */
- ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
- s->f = ssh2_pkt_getmp(pktin);
- if (!s->f) {
- bombout(("unable to parse key exchange reply packet"));
- crStop(0);
- }
- ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
+ {
+ char *keydata;
+ ssh_pkt_getstring(pktin, &keydata, &s->rsakeylen);
+ s->rsakeydata = snewn(s->rsakeylen, char);
+ memcpy(s->rsakeydata, keydata, s->rsakeylen);
+ }
+
+ s->rsakey = ssh_rsakex_newkey(s->rsakeydata, s->rsakeylen);
+ if (!s->rsakey) {
+ sfree(s->rsakeydata);
+ bombout(("unable to parse RSA public key from server"));
+ crStop(0);
+ }
+
+ hash_string(ssh->kex->hash, ssh->exhash, s->rsakeydata, s->rsakeylen);
+
+ /*
+ * Next, set up a shared secret K, of precisely KLEN -
+ * 2*HLEN - 49 bits, where KLEN is the bit length of the
+ * RSA key modulus and HLEN is the bit length of the hash
+ * we're using.
+ */
+ {
+ int klen = ssh_rsakex_klen(s->rsakey);
+ int nbits = klen - (2*ssh->kex->hash->hlen*8 + 49);
+ int i, byte = 0;
+ unsigned char *kstr1, *kstr2, *outstr;
+ int kstr1len, kstr2len, outstrlen;
+
+ s->K = bn_power_2(nbits - 1);
+
+ for (i = 0; i < nbits; i++) {
+ if ((i & 7) == 0) {
+ byte = random_byte();
+ }
+ bignum_set_bit(s->K, i, (byte >> (i & 7)) & 1);
+ }
+
+ /*
+ * Encode this as an mpint.
+ */
+ kstr1 = ssh2_mpint_fmt(s->K, &kstr1len);
+ kstr2 = snewn(kstr2len = 4 + kstr1len, unsigned char);
+ PUT_32BIT(kstr2, kstr1len);
+ memcpy(kstr2 + 4, kstr1, kstr1len);
+
+ /*
+ * Encrypt it with the given RSA key.
+ */
+ outstrlen = (klen + 7) / 8;
+ outstr = snewn(outstrlen, unsigned char);
+ ssh_rsakex_encrypt(ssh->kex->hash, kstr2, kstr2len,
+ outstr, outstrlen, s->rsakey);
+
+ /*
+ * And send it off in a return packet.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_KEXRSA_SECRET);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, (char *)outstr, outstrlen);
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+
+ hash_string(ssh->kex->hash, ssh->exhash, outstr, outstrlen);
+
+ sfree(kstr2);
+ sfree(kstr1);
+ sfree(outstr);
+ }
+
+ ssh_rsakex_freekey(s->rsakey);
- s->K = dh_find_K(ssh->kex_ctx, s->f);
+ crWaitUntil(pktin);
+ if (pktin->type != SSH2_MSG_KEXRSA_DONE) {
+ sfree(s->rsakeydata);
+ bombout(("expected signature packet from server"));
+ crStop(0);
+ }
- /* We assume everything from now on will be quick, and it might
- * involve user interaction. */
- set_busy_status(ssh->frontend, BUSY_NOT);
+ ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
- sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
- if (ssh->kex == &ssh_diffiehellman_gex) {
- sha_uint32(&ssh->exhash, s->pbits);
- sha_mpint(&ssh->exhash, s->p);
- sha_mpint(&ssh->exhash, s->g);
+ sfree(s->rsakeydata);
}
- sha_mpint(&ssh->exhash, s->e);
- sha_mpint(&ssh->exhash, s->f);
- sha_mpint(&ssh->exhash, s->K);
- SHA_Final(&ssh->exhash, s->exchange_hash);
- dh_cleanup(ssh->kex_ctx);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->K);
+ assert(ssh->kex->hash->hlen <= sizeof(s->exchange_hash));
+ ssh->kex->hash->final(ssh->exhash, s->exchange_hash);
+
ssh->kex_ctx = NULL;
#if 0
debug(("Exchange hash is:\n"));
- dmemdump(s->exchange_hash, 20);
+ dmemdump(s->exchange_hash, ssh->kex->hash->hlen);
#endif
- s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
if (!s->hkey ||
!ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
- (char *)s->exchange_hash, 20)) {
+ (char *)s->exchange_hash,
+ ssh->kex->hash->hlen)) {
bombout(("Server's host key did not match the signature supplied"));
crStop(0);
}
}
ssh_set_frozen(ssh, 0);
if (s->dlgret == 0) {
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "User aborted at host key verification", NULL,
+ 0, TRUE);
crStop(0);
}
if (!s->got_session_id) { /* don't bother logging this in rekeys */
* authentication.
*/
if (!s->got_session_id) {
+ assert(sizeof(s->exchange_hash) <= sizeof(ssh->v2_session_id));
memcpy(ssh->v2_session_id, s->exchange_hash,
sizeof(s->exchange_hash));
+ ssh->v2_session_id_len = ssh->kex->hash->hlen;
+ assert(ssh->v2_session_id_len <= sizeof(ssh->v2_session_id));
s->got_session_id = TRUE;
}
* hash from the _first_ key exchange.
*/
{
- unsigned char keyspace[40];
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
+ unsigned char keyspace[SSH2_KEX_MAX_HASH_LEN * SSH2_MKKEY_ITERS];
+ assert(sizeof(keyspace) >= ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'C',keyspace);
+ assert((ssh->cscipher->keylen+7) / 8 <=
+ ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'A',keyspace);
+ assert(ssh->cscipher->blksize <=
+ ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'E',keyspace);
+ assert(ssh->csmac->len <=
+ ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
+ memset(keyspace, 0, sizeof(keyspace));
}
logeventf(ssh, "Initialised %.200s client->server encryption",
* hash from the _first_ key exchange.
*/
{
- unsigned char keyspace[40];
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
+ unsigned char keyspace[SSH2_KEX_MAX_HASH_LEN * SSH2_MKKEY_ITERS];
+ assert(sizeof(keyspace) >= ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'D',keyspace);
+ assert((ssh->sccipher->keylen+7) / 8 <=
+ ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'B',keyspace);
+ assert(ssh->sccipher->blksize <=
+ ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'F',keyspace);
+ assert(ssh->scmac->len <=
+ ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
+ memset(keyspace, 0, sizeof(keyspace));
}
logeventf(ssh, "Initialised %.200s server->client encryption",
ssh->sccipher->text_name);
ssh->sccomp->text_name);
/*
- * Free key exchange data.
+ * Free shared secret.
*/
- freebn(s->f);
freebn(s->K);
- if (ssh->kex == &ssh_diffiehellman_gex) {
- freebn(s->g);
- freebn(s->p);
- }
/*
* Key exchange is over. Loop straight back round if we have a
* it would only confuse the layer above.
*/
if (s->activated_authconn) {
- crReturn(1);
+ crReturn(0);
}
s->activated_authconn = TRUE;
len = c->v.v2.remmaxpkt;
pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
ssh2_pkt_adduint32(pktout, c->remoteid);
- dont_log_data(ssh, pktout, PKTLOG_OMIT);
ssh2_pkt_addstring_start(pktout);
+ dont_log_data(ssh, pktout, PKTLOG_OMIT);
ssh2_pkt_addstring_data(pktout, data, len);
end_log_omission(ssh, pktout);
ssh2_pkt_send(ssh, pktout);
case CHAN_AGENT:
while (length > 0) {
if (c->u.a.lensofar < 4) {
- unsigned int l = min(4 - c->u.a.lensofar, length);
+ unsigned int l = min(4 - c->u.a.lensofar,
+ (unsigned)length);
memcpy(c->u.a.msglen + c->u.a.lensofar,
data, l);
data += l;
if (c->u.a.lensofar >= 4 && length > 0) {
unsigned int l =
min(c->u.a.totallen - c->u.a.lensofar,
- length);
+ (unsigned)length);
memcpy(c->u.a.message + c->u.a.lensofar,
data, l);
data += l;
/*
* If we are not buffering too much data,
* enlarge the window again at the remote side.
+ * If we are buffering too much, we may still
+ * need to adjust the window if the server's
+ * sent excess data.
*/
- if (bufsize < OUR_V2_WINSIZE)
- ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
+ ssh2_set_window(c, bufsize < OUR_V2_WINSIZE ?
+ OUR_V2_WINSIZE - bufsize : 0);
}
}
* not running in -N mode.)
*/
if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
- logevent("All channels closed. Disconnecting");
-#if 0
/*
* We used to send SSH_MSG_DISCONNECT here,
* because I'd believed that _every_ conforming
* this is more polite than sending a
* DISCONNECT. So now we don't.
*/
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "All open channels closed");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
-#endif
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "All channels closed", NULL, 0, TRUE);
}
}
*/
c = find234(ssh->channels, &localid, ssh_channelfind);
if (!c) {
- char buf[80];
- sprintf(buf, "Received channel request for nonexistent"
- " channel %d", localid);
- logevent(buf);
- pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(pktout, buf);
- ssh2_pkt_addstring(pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, pktout);
- connection_fatal(ssh->frontend, "%s", buf);
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ char *buf = dupprintf("Received channel request for nonexistent"
+ " channel %d", localid);
+ ssh_disconnect(ssh, NULL, buf, SSH2_DISCONNECT_PROTOCOL_ERROR, FALSE);
+ sfree(buf);
return;
}
is_plausible = FALSE;
}
}
+ ssh->exitcode = 128; /* means `unknown signal' */
if (is_plausible) {
if (is_int) {
/* Old non-standard OpenSSH. */
int signum = ssh_pkt_getuint32(pktin);
fmt_sig = dupprintf(" %d", signum);
+ ssh->exitcode = 128 + signum;
} else {
/* As per the drafts. */
char *sig;
fmt_sig = dupprintf(" \"%.*s\"",
siglen, sig);
}
+
+ /*
+ * Really hideous method of translating the
+ * signal description back into a locally
+ * meaningful number.
+ */
+
+ if (0)
+ ;
+#define TRANSLATE_SIGNAL(s) \
+ else if (siglen == lenof(#s)-1 && !memcmp(sig, #s, siglen)) \
+ ssh->exitcode = 128 + SIG ## s
+#ifdef SIGABRT
+ TRANSLATE_SIGNAL(ABRT);
+#endif
+#ifdef SIGALRM
+ TRANSLATE_SIGNAL(ALRM);
+#endif
+#ifdef SIGFPE
+ TRANSLATE_SIGNAL(FPE);
+#endif
+#ifdef SIGHUP
+ TRANSLATE_SIGNAL(HUP);
+#endif
+#ifdef SIGILL
+ TRANSLATE_SIGNAL(ILL);
+#endif
+#ifdef SIGINT
+ TRANSLATE_SIGNAL(INT);
+#endif
+#ifdef SIGKILL
+ TRANSLATE_SIGNAL(KILL);
+#endif
+#ifdef SIGPIPE
+ TRANSLATE_SIGNAL(PIPE);
+#endif
+#ifdef SIGQUIT
+ TRANSLATE_SIGNAL(QUIT);
+#endif
+#ifdef SIGSEGV
+ TRANSLATE_SIGNAL(SEGV);
+#endif
+#ifdef SIGTERM
+ TRANSLATE_SIGNAL(TERM);
+#endif
+#ifdef SIGUSR1
+ TRANSLATE_SIGNAL(USR1);
+#endif
+#ifdef SIGUSR2
+ TRANSLATE_SIGNAL(USR2);
+#endif
+#undef TRANSLATE_SIGNAL
+ else
+ ssh->exitcode = 128;
}
core = ssh2_pkt_getbool(pktin);
ssh_pkt_getstring(pktin, &msg, &msglen);
}
}
} else if (typelen == 22 &&
- !memcmp(type, "auth-agent@openssh.com", 3)) {
+ !memcmp(type, "auth-agent@openssh.com", 22)) {
if (!ssh->agentfwd_enabled)
error = "Agent forwarding is not enabled";
else {
{
struct do_ssh2_authconn_state {
enum {
- AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
- AUTH_PASSWORD,
- AUTH_KEYBOARD_INTERACTIVE
- } method;
- enum {
AUTH_TYPE_NONE,
AUTH_TYPE_PUBLICKEY,
AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
} type;
int done_service_req;
int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
- int tried_pubkey_config, tried_agent;
- int kbd_inter_running, kbd_inter_refused;
+ int tried_pubkey_config, done_agent;
+ int kbd_inter_refused;
int we_are_in;
- int num_prompts, curr_prompt, echo;
+ prompts_t *cur_prompt;
+ int num_prompts;
char username[100];
+ char *password;
int got_username;
- char pwprompt[512];
- char password[100];
void *publickey_blob;
int publickey_bloblen;
- unsigned char request[5], *response, *p;
- int responselen;
+ int publickey_encrypted;
+ char *publickey_algorithm;
+ char *publickey_comment;
+ unsigned char agent_request[5], *agent_response, *agentp;
+ int agent_responselen;
+ unsigned char *pkblob_in_agent;
int keyi, nkeys;
- int authed;
char *pkblob, *alg, *commentp;
int pklen, alglen, commentlen;
int siglen, retlen, len;
}
}
+ /* Arrange to be able to deal with any BANNERs that come in.
+ * (We do this now as packets may come in during the next bit.) */
+ bufchain_init(&ssh->banner);
+ ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] =
+ ssh2_msg_userauth_banner;
+
/*
- * We repeat this whole loop, including the username prompt,
- * until we manage a successful authentication. If the user
- * types the wrong _password_, they can be sent back to the
- * beginning to try another username, if this is configured on.
- * (If they specify a username in the config, they are never
+ * Misc one-time setup for authentication.
+ */
+ s->publickey_blob = NULL;
+ if (!s->we_are_in) {
+
+ /*
+ * Load the public half of any configured public key file
+ * for later use.
+ */
+ if (!filename_is_null(ssh->cfg.keyfile)) {
+ int keytype;
+ logeventf(ssh, "Reading private key file \"%.150s\"",
+ filename_to_str(&ssh->cfg.keyfile));
+ keytype = key_type(&ssh->cfg.keyfile);
+ if (keytype == SSH_KEYTYPE_SSH2) {
+ const char *error;
+ s->publickey_blob =
+ ssh2_userkey_loadpub(&ssh->cfg.keyfile,
+ &s->publickey_algorithm,
+ &s->publickey_bloblen,
+ &s->publickey_comment, &error);
+ if (s->publickey_blob) {
+ s->publickey_encrypted =
+ ssh2_userkey_encrypted(&ssh->cfg.keyfile, NULL);
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to load private key (%s)",
+ error);
+ msgbuf = dupprintf("Unable to load private key file "
+ "\"%.150s\" (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ error);
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
+ }
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to use this key file (%s)",
+ key_type_to_str(keytype));
+ msgbuf = dupprintf("Unable to use key file \"%.150s\""
+ " (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ key_type_to_str(keytype));
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
+ s->publickey_blob = NULL;
+ }
+ }
+
+ /*
+ * Find out about any keys Pageant has (but if there's a
+ * public key configured, filter out all others).
+ */
+ s->nkeys = 0;
+ s->agent_response = NULL;
+ s->pkblob_in_agent = NULL;
+ if (ssh->cfg.tryagent && agent_exists()) {
+
+ void *r;
+
+ logevent("Pageant is running. Requesting keys.");
+
+ /* Request the keys held by the agent. */
+ PUT_32BIT(s->agent_request, 1);
+ s->agent_request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
+ if (!agent_query(s->agent_request, 5, &r, &s->agent_responselen,
+ ssh_agent_callback, ssh)) {
+ do {
+ crReturnV;
+ if (pktin) {
+ bombout(("Unexpected data from server while"
+ " waiting for agent response"));
+ crStopV;
+ }
+ } while (pktin || inlen > 0);
+ r = ssh->agent_response;
+ s->agent_responselen = ssh->agent_response_len;
+ }
+ s->agent_response = (unsigned char *) r;
+ if (s->agent_response && s->agent_responselen >= 5 &&
+ s->agent_response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
+ int keyi;
+ unsigned char *p;
+ p = s->agent_response + 5;
+ s->nkeys = GET_32BIT(p);
+ p += 4;
+ logeventf(ssh, "Pageant has %d SSH-2 keys", s->nkeys);
+ if (s->publickey_blob) {
+ /* See if configured key is in agent. */
+ for (keyi = 0; keyi < s->nkeys; keyi++) {
+ s->pklen = GET_32BIT(p);
+ if (s->pklen == s->publickey_bloblen &&
+ !memcmp(p+4, s->publickey_blob,
+ s->publickey_bloblen)) {
+ logeventf(ssh, "Pageant key #%d matches "
+ "configured key file", keyi);
+ s->keyi = keyi;
+ s->pkblob_in_agent = p;
+ break;
+ }
+ p += 4 + s->pklen;
+ p += GET_32BIT(p) + 4; /* comment */
+ }
+ if (!s->pkblob_in_agent) {
+ logevent("Configured key file not in Pageant");
+ s->nkeys = 0;
+ }
+ }
+ }
+ }
+
+ }
+
+ /*
+ * We repeat this whole loop, including the username prompt,
+ * until we manage a successful authentication. If the user
+ * types the wrong _password_, they can be sent back to the
+ * beginning to try another username, if this is configured on.
+ * (If they specify a username in the config, they are never
* asked, even if they do give a wrong password.)
*
* I think this best serves the needs of
*/
s->username[0] = '\0';
s->got_username = FALSE;
- bufchain_init(&ssh->banner);
- ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] =
- ssh2_msg_userauth_banner;
while (!s->we_are_in) {
/*
* Get a username.
* it again.
*/
} else if (!*ssh->cfg.username) {
- if (ssh_get_line && !ssh_getline_pw_only) {
- if (!ssh_get_line("login as: ",
- s->username, sizeof(s->username), FALSE)) {
- /*
- * get_line failed to get a username.
- * Terminate.
- */
- logevent("No username provided. Abandoning session.");
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
- }
- } else {
- int ret; /* need not be saved across crReturn */
- c_write_str(ssh, "login as: ");
+ int ret; /* need not be kept over crReturn */
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH login name");
+ add_prompt(s->cur_prompt, dupstr("login as: "), TRUE,
+ lenof(s->username));
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
ssh->send_ok = 1;
- setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
- do {
- crWaitUntilV(!pktin);
- ret = process_userpass_input(ssh, in, inlen);
- } while (ret == 0);
- if (ret < 0)
- cleanup_exit(0);
- c_write_str(ssh, "\r\n");
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
}
- s->username[strcspn(s->username, "\n\r")] = '\0';
+ if (!ret) {
+ /*
+ * get_userpass_input() failed to get a username.
+ * Terminate.
+ */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, "No username provided", NULL, 0, TRUE);
+ crStopV;
+ }
+ memcpy(s->username, s->cur_prompt->prompts[0]->result,
+ lenof(s->username));
+ free_prompts(s->cur_prompt);
} else {
char *stuff;
strncpy(s->username, ssh->cfg.username, sizeof(s->username));
* just in case it succeeds, and (b) so that we know what
* authentication methods we can usefully try next.
*/
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh->pkt_actx = SSH2_PKTCTX_NOAUTH;
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
ssh2_pkt_addstring(s->pktout, s->username);
s->we_are_in = FALSE;
s->tried_pubkey_config = FALSE;
- s->tried_agent = FALSE;
- s->kbd_inter_running = FALSE;
s->kbd_inter_refused = FALSE;
- /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
- if (!filename_is_null(ssh->cfg.keyfile)) {
- int keytype;
- logeventf(ssh, "Reading private key file \"%.150s\"",
- filename_to_str(&ssh->cfg.keyfile));
- keytype = key_type(&ssh->cfg.keyfile);
- if (keytype == SSH_KEYTYPE_SSH2) {
- s->publickey_blob =
- ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
- &s->publickey_bloblen, NULL);
+
+ /* Reset agent request state. */
+ s->done_agent = FALSE;
+ if (s->agent_response) {
+ if (s->pkblob_in_agent) {
+ s->agentp = s->pkblob_in_agent;
} else {
- char *msgbuf;
- logeventf(ssh, "Unable to use this key file (%s)",
- key_type_to_str(keytype));
- msgbuf = dupprintf("Unable to use key file \"%.150s\""
- " (%s)\r\n",
- filename_to_str(&ssh->cfg.keyfile),
- key_type_to_str(keytype));
- c_write_str(ssh, msgbuf);
- sfree(msgbuf);
- s->publickey_blob = NULL;
+ s->agentp = s->agent_response + 5 + 4;
+ s->keyi = 0;
}
- } else
- s->publickey_blob = NULL;
+ }
while (1) {
/*
break;
}
- if (s->kbd_inter_running &&
- pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
- /*
- * This is either a further set-of-prompts packet
- * in keyboard-interactive authentication, or it's
- * the same one and we came back here with `gotit'
- * set. In the former case, we must reset the
- * curr_prompt variable.
- */
- if (!s->gotit)
- s->curr_prompt = 0;
- } else if (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
- /* FIXME: perhaps we should support this? */
- bombout(("PASSWD_CHANGEREQ not yet supported"));
- crStopV;
- } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
- bombout(("Strange packet received during authentication: type %d",
- pktin->type));
+ if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
+ bombout(("Strange packet received during authentication: "
+ "type %d", pktin->type));
crStopV;
}
char *methods;
int methlen;
ssh_pkt_getstring(pktin, &methods, &methlen);
- s->kbd_inter_running = FALSE;
if (!ssh2_pkt_getbool(pktin)) {
/*
* We have received an unequivocal Access
in_commasep_string("keyboard-interactive", methods, methlen);
}
- s->method = 0;
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- s->need_pw = FALSE;
+ ssh->pkt_actx = SSH2_PKTCTX_NOAUTH;
- /*
- * Most password/passphrase prompts will be
- * non-echoing, so we set this to 0 by default.
- * Exception is that some keyboard-interactive prompts
- * can be echoing, in which case we'll set this to 1.
- */
- s->echo = 0;
+ if (s->can_pubkey && !s->done_agent && s->nkeys) {
- if (!s->method && s->can_pubkey &&
- agent_exists() && !s->tried_agent) {
/*
- * Attempt public-key authentication using Pageant.
+ * Attempt public-key authentication using a key from Pageant.
*/
- void *r;
- s->authed = FALSE;
-
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
-
- s->tried_agent = TRUE;
-
- logevent("Pageant is running. Requesting keys.");
-
- /* Request the keys held by the agent. */
- PUT_32BIT(s->request, 1);
- s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
- if (!agent_query(s->request, 5, &r, &s->responselen,
- ssh_agent_callback, ssh)) {
- do {
- crReturnV;
- if (pktin) {
- bombout(("Unexpected data from server while"
- " waiting for agent response"));
- crStopV;
- }
- } while (pktin || inlen > 0);
- r = ssh->agent_response;
- s->responselen = ssh->agent_response_len;
- }
- s->response = (unsigned char *) r;
- if (s->response && s->responselen >= 5 &&
- s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
- s->p = s->response + 5;
- s->nkeys = GET_32BIT(s->p);
- s->p += 4;
- logeventf(ssh, "Pageant has %d SSH-2 keys", s->nkeys);
- for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
- void *vret;
- logeventf(ssh, "Trying Pageant key #%d", s->keyi);
- s->pklen = GET_32BIT(s->p);
- s->p += 4;
- if (s->publickey_blob &&
- s->pklen == s->publickey_bloblen &&
- !memcmp(s->p, s->publickey_blob,
- s->publickey_bloblen)) {
- logevent("This key matches configured key file");
- s->tried_pubkey_config = 1;
- }
- s->pkblob = (char *)s->p;
- s->p += s->pklen;
- s->alglen = GET_32BIT(s->pkblob);
- s->alg = s->pkblob + 4;
- s->commentlen = GET_32BIT(s->p);
- s->p += 4;
- s->commentp = (char *)s->p;
- s->p += s->commentlen;
- s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
- ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
- ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
- ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
- ssh2_pkt_send(ssh, s->pktout);
-
- crWaitUntilV(pktin);
- if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
- logevent("Key refused");
- continue;
- }
+ ssh->pkt_actx = SSH2_PKTCTX_PUBLICKEY;
- if (flags & FLAG_VERBOSE) {
- c_write_str(ssh, "Authenticating with "
- "public key \"");
- c_write(ssh, s->commentp, s->commentlen);
- c_write_str(ssh, "\" from agent\r\n");
- }
+ logeventf(ssh, "Trying Pageant key #%d", s->keyi);
- /*
- * Server is willing to accept the key.
- * Construct a SIGN_REQUEST.
- */
- s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
- ssh2_pkt_addbool(s->pktout, TRUE);
- ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
- ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
-
- s->siglen = s->pktout->length - 5 + 4 + 20;
- if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
- s->siglen -= 4;
- s->len = 1; /* message type */
- s->len += 4 + s->pklen; /* key blob */
- s->len += 4 + s->siglen; /* data to sign */
- s->len += 4; /* flags */
- s->agentreq = snewn(4 + s->len, char);
- PUT_32BIT(s->agentreq, s->len);
- s->q = s->agentreq + 4;
- *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
- PUT_32BIT(s->q, s->pklen);
- s->q += 4;
- memcpy(s->q, s->pkblob, s->pklen);
- s->q += s->pklen;
- PUT_32BIT(s->q, s->siglen);
- s->q += 4;
- /* Now the data to be signed... */
- if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
- PUT_32BIT(s->q, 20);
- s->q += 4;
- }
- memcpy(s->q, ssh->v2_session_id, 20);
- s->q += 20;
- memcpy(s->q, s->pktout->data + 5,
- s->pktout->length - 5);
- s->q += s->pktout->length - 5;
- /* And finally the (zero) flags word. */
- PUT_32BIT(s->q, 0);
- if (!agent_query(s->agentreq, s->len + 4,
- &vret, &s->retlen,
- ssh_agent_callback, ssh)) {
- do {
- crReturnV;
- if (pktin) {
- bombout(("Unexpected data from server"
- " while waiting for agent"
- " response"));
- crStopV;
- }
- } while (pktin || inlen > 0);
- vret = ssh->agent_response;
- s->retlen = ssh->agent_response_len;
- }
- s->ret = vret;
- sfree(s->agentreq);
- if (s->ret) {
- if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
- logevent("Sending Pageant's response");
- ssh2_add_sigblob(ssh, s->pktout,
- s->pkblob, s->pklen,
- s->ret + 9,
- GET_32BIT(s->ret + 5));
- ssh2_pkt_send(ssh, s->pktout);
- s->authed = TRUE;
- break;
- } else {
- logevent
- ("Pageant failed to answer challenge");
- sfree(s->ret);
- }
- }
- }
- if (s->authed)
- continue;
- }
- sfree(s->response);
- }
+ /* Unpack key from agent response */
+ s->pklen = GET_32BIT(s->agentp);
+ s->agentp += 4;
+ s->pkblob = (char *)s->agentp;
+ s->agentp += s->pklen;
+ s->alglen = GET_32BIT(s->pkblob);
+ s->alg = s->pkblob + 4;
+ s->commentlen = GET_32BIT(s->agentp);
+ s->agentp += 4;
+ s->commentp = (char *)s->agentp;
+ s->agentp += s->commentlen;
+ /* s->agentp now points at next key, if any */
- if (!s->method && s->can_pubkey && s->publickey_blob
- && !s->tried_pubkey_config) {
- unsigned char *pub_blob;
- char *algorithm, *comment;
- int pub_blob_len;
+ /* See if server will accept it */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey");
+ /* method */
+ ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
+ ssh2_pkt_send(ssh, s->pktout);
+ s->type = AUTH_TYPE_PUBLICKEY_OFFER_QUIET;
- s->tried_pubkey_config = TRUE;
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
+ /* Offer of key refused. */
+ s->gotit = TRUE;
- /*
- * Try the public key supplied in the configuration.
- *
- * First, offer the public blob to see if the server is
- * willing to accept it.
- */
- pub_blob =
- (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
- &algorithm,
- &pub_blob_len,
- NULL);
- if (pub_blob) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
- ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
- ssh2_pkt_addstring(s->pktout, algorithm);
- ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
- pub_blob_len);
- ssh2_pkt_send(ssh, s->pktout);
- logevent("Offered public key");
+ } else {
+
+ void *vret;
- crWaitUntilV(pktin);
- if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
- s->gotit = TRUE;
- s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
- continue; /* key refused; give up on it */
+ if (flags & FLAG_VERBOSE) {
+ c_write_str(ssh, "Authenticating with "
+ "public key \"");
+ c_write(ssh, s->commentp, s->commentlen);
+ c_write_str(ssh, "\" from agent\r\n");
}
- logevent("Offer of public key accepted");
/*
- * Actually attempt a serious authentication using
- * the key.
+ * Server is willing to accept the key.
+ * Construct a SIGN_REQUEST.
*/
- if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
- sprintf(s->pwprompt,
- "Passphrase for key \"%.100s\": ",
- comment);
- s->need_pw = TRUE;
- } else {
- s->need_pw = FALSE;
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey");
+ /* method */
+ ssh2_pkt_addbool(s->pktout, TRUE); /* signature included */
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
+
+ /* Ask agent for signature. */
+ s->siglen = s->pktout->length - 5 + 4 +
+ ssh->v2_session_id_len;
+ if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
+ s->siglen -= 4;
+ s->len = 1; /* message type */
+ s->len += 4 + s->pklen; /* key blob */
+ s->len += 4 + s->siglen; /* data to sign */
+ s->len += 4; /* flags */
+ s->agentreq = snewn(4 + s->len, char);
+ PUT_32BIT(s->agentreq, s->len);
+ s->q = s->agentreq + 4;
+ *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
+ PUT_32BIT(s->q, s->pklen);
+ s->q += 4;
+ memcpy(s->q, s->pkblob, s->pklen);
+ s->q += s->pklen;
+ PUT_32BIT(s->q, s->siglen);
+ s->q += 4;
+ /* Now the data to be signed... */
+ if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
+ PUT_32BIT(s->q, ssh->v2_session_id_len);
+ s->q += 4;
}
- if (flags & FLAG_VERBOSE) {
- c_write_str(ssh, "Authenticating with public key \"");
- c_write_str(ssh, comment);
- c_write_str(ssh, "\"\r\n");
+ memcpy(s->q, ssh->v2_session_id,
+ ssh->v2_session_id_len);
+ s->q += ssh->v2_session_id_len;
+ memcpy(s->q, s->pktout->data + 5,
+ s->pktout->length - 5);
+ s->q += s->pktout->length - 5;
+ /* And finally the (zero) flags word. */
+ PUT_32BIT(s->q, 0);
+ if (!agent_query(s->agentreq, s->len + 4,
+ &vret, &s->retlen,
+ ssh_agent_callback, ssh)) {
+ do {
+ crReturnV;
+ if (pktin) {
+ bombout(("Unexpected data from server"
+ " while waiting for agent"
+ " response"));
+ crStopV;
+ }
+ } while (pktin || inlen > 0);
+ vret = ssh->agent_response;
+ s->retlen = ssh->agent_response_len;
+ }
+ s->ret = vret;
+ sfree(s->agentreq);
+ if (s->ret) {
+ if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
+ logevent("Sending Pageant's response");
+ ssh2_add_sigblob(ssh, s->pktout,
+ s->pkblob, s->pklen,
+ s->ret + 9,
+ GET_32BIT(s->ret + 5));
+ ssh2_pkt_send(ssh, s->pktout);
+ s->type = AUTH_TYPE_PUBLICKEY;
+ } else {
+ /* FIXME: less drastic response */
+ bombout(("Pageant failed to answer challenge"));
+ crStopV;
+ }
}
- s->method = AUTH_PUBLICKEY_FILE;
}
- }
- if (!s->method && s->can_keyb_inter && !s->kbd_inter_refused &&
- !s->kbd_inter_running) {
- s->method = AUTH_KEYBOARD_INTERACTIVE;
- s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+ /* Do we have any keys left to try? */
+ if (s->pkblob_in_agent) {
+ s->done_agent = TRUE;
+ s->tried_pubkey_config = TRUE;
+ } else {
+ s->keyi++;
+ if (s->keyi >= s->nkeys)
+ s->done_agent = TRUE;
+ }
+
+ } else if (s->can_pubkey && s->publickey_blob &&
+ !s->tried_pubkey_config) {
+
+ struct ssh2_userkey *key; /* not live over crReturn */
+ char *passphrase; /* not live over crReturn */
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
+ ssh->pkt_actx = SSH2_PKTCTX_PUBLICKEY;
+ s->tried_pubkey_config = TRUE;
+
+ /*
+ * Try the public key supplied in the configuration.
+ *
+ * First, offer the public blob to see if the server is
+ * willing to accept it.
+ */
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
- ssh2_pkt_addstring(s->pktout, ""); /* lang */
- ssh2_pkt_addstring(s->pktout, "");
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
+ ssh2_pkt_addbool(s->pktout, FALSE);
+ /* no signature included */
+ ssh2_pkt_addstring(s->pktout, s->publickey_algorithm);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout,
+ (char *)s->publickey_blob,
+ s->publickey_bloblen);
ssh2_pkt_send(ssh, s->pktout);
+ logevent("Offered public key");
crWaitUntilV(pktin);
- if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
- if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
- s->gotit = TRUE;
- logevent("Keyboard-interactive authentication refused");
- s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
- s->kbd_inter_refused = TRUE; /* don't try it again */
- continue;
- }
-
- c_write_str(ssh, "Using keyboard-interactive authentication.\r\n");
- s->kbd_inter_running = TRUE;
- s->curr_prompt = 0;
- }
-
- if (s->kbd_inter_running) {
- s->method = AUTH_KEYBOARD_INTERACTIVE;
- s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
-
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
-
- if (s->curr_prompt == 0) {
- /*
- * We've got a fresh USERAUTH_INFO_REQUEST.
- * Display header data, and start going through
- * the prompts.
- */
- char *name, *inst, *lang;
- int name_len, inst_len, lang_len;
-
- ssh_pkt_getstring(pktin, &name, &name_len);
- ssh_pkt_getstring(pktin, &inst, &inst_len);
- ssh_pkt_getstring(pktin, &lang, &lang_len);
- if (name_len > 0) {
- c_write_untrusted(ssh, name, name_len);
- c_write_str(ssh, "\r\n");
- }
- if (inst_len > 0) {
- c_write_untrusted(ssh, inst, inst_len);
- c_write_str(ssh, "\r\n");
- }
- s->num_prompts = ssh_pkt_getuint32(pktin);
+ if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
+ /* Key refused. Give up. */
+ s->gotit = TRUE; /* reconsider message next loop */
+ s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
+ continue; /* process this new message */
}
+ logevent("Offer of public key accepted");
/*
- * If there are prompts remaining in the packet,
- * display one and get a response.
+ * Actually attempt a serious authentication using
+ * the key.
*/
- if (s->curr_prompt < s->num_prompts) {
- char *prompt;
- int prompt_len;
-
- ssh_pkt_getstring(pktin, &prompt, &prompt_len);
- if (prompt_len > 0) {
- static const char trunc[] = "<prompt truncated>: ";
- static const int prlen = sizeof(s->pwprompt) -
- lenof(trunc);
- if (prompt_len > prlen) {
- memcpy(s->pwprompt, prompt, prlen);
- strcpy(s->pwprompt + prlen, trunc);
- } else {
- memcpy(s->pwprompt, prompt, prompt_len);
- s->pwprompt[prompt_len] = '\0';
+ if (flags & FLAG_VERBOSE) {
+ c_write_str(ssh, "Authenticating with public key \"");
+ c_write_str(ssh, s->publickey_comment);
+ c_write_str(ssh, "\"\r\n");
+ }
+ key = NULL;
+ while (!key) {
+ const char *error; /* not live over crReturn */
+ if (s->publickey_encrypted) {
+ /*
+ * Get a passphrase from the user.
+ */
+ int ret; /* need not be kept over crReturn */
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = FALSE;
+ s->cur_prompt->name = dupstr("SSH key passphrase");
+ add_prompt(s->cur_prompt,
+ dupprintf("Passphrase for key \"%.100s\": ",
+ s->publickey_comment),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt,
+ in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /* Failed to get a passphrase. Terminate. */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL,
+ "Unable to authenticate",
+ SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
+ TRUE);
+ crStopV;
}
+ passphrase =
+ dupstr(s->cur_prompt->prompts[0]->result);
+ free_prompts(s->cur_prompt);
} else {
- strcpy(s->pwprompt,
- "<server failed to send prompt>: ");
+ passphrase = NULL; /* no passphrase needed */
}
- s->echo = ssh2_pkt_getbool(pktin);
- s->need_pw = TRUE;
- } else
- s->need_pw = FALSE;
- }
- if (!s->method && s->can_passwd) {
- s->method = AUTH_PASSWORD;
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
- sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
- ssh->savedhost);
- s->need_pw = TRUE;
- }
-
- if (s->need_pw) {
- if (ssh_get_line) {
- if (!ssh_get_line(s->pwprompt, s->password,
- sizeof(s->password), TRUE)) {
- /*
- * get_line failed to get a password (for
- * example because one was supplied on the
- * command line which has already failed to
- * work). Terminate.
- */
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "No more passwords available"
- " to try");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
- logevent("Unable to authenticate");
- connection_fatal(ssh->frontend,
- "Unable to authenticate");
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
+ /*
+ * Try decrypting the key.
+ */
+ key = ssh2_load_userkey(&ssh->cfg.keyfile, passphrase,
+ &error);
+ if (passphrase) {
+ /* burn the evidence */
+ memset(passphrase, 0, strlen(passphrase));
+ sfree(passphrase);
+ }
+ if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
+ if (passphrase &&
+ (key == SSH2_WRONG_PASSPHRASE)) {
+ c_write_str(ssh, "Wrong passphrase\r\n");
+ key = NULL;
+ /* and loop again */
+ } else {
+ c_write_str(ssh, "Unable to load private key (");
+ c_write_str(ssh, error);
+ c_write_str(ssh, ")\r\n");
+ key = NULL;
+ break; /* try something else */
+ }
}
- } else {
- int ret; /* need not be saved across crReturn */
- c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
- ssh->send_ok = 1;
-
- setup_userpass_input(ssh, s->password,
- sizeof(s->password), s->echo);
- do {
- crWaitUntilV(!pktin);
- ret = process_userpass_input(ssh, in, inlen);
- } while (ret == 0);
- if (ret < 0)
- cleanup_exit(0);
- c_write_str(ssh, "\r\n");
}
- }
- if (s->method == AUTH_PUBLICKEY_FILE) {
- /*
- * We have our passphrase. Now try the actual authentication.
- */
- struct ssh2_userkey *key;
- const char *error = NULL;
-
- key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
- &error);
- if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
- if (key == SSH2_WRONG_PASSPHRASE) {
- c_write_str(ssh, "Wrong passphrase\r\n");
- s->tried_pubkey_config = FALSE;
- } else {
- c_write_str(ssh, "Unable to load private key (");
- c_write_str(ssh, error);
- c_write_str(ssh, ")\r\n");
- s->tried_pubkey_config = TRUE;
- }
- /* Send a spurious AUTH_NONE to return to the top. */
- s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "none"); /* method */
- ssh2_pkt_send(ssh, s->pktout);
- s->type = AUTH_TYPE_NONE;
- } else {
+ if (key) {
unsigned char *pkblob, *sigblob, *sigdata;
int pkblob_len, sigblob_len, sigdata_len;
- int p;
+ int p;
/*
* We have loaded the private key and the server
*/
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey");
+ /* method */
ssh2_pkt_addbool(s->pktout, TRUE);
+ /* signature follows */
ssh2_pkt_addstring(s->pktout, key->alg->name);
- pkblob = key->alg->public_blob(key->data, &pkblob_len);
+ pkblob = key->alg->public_blob(key->data,
+ &pkblob_len);
ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
+ ssh2_pkt_addstring_data(s->pktout, (char *)pkblob,
+ pkblob_len);
/*
* The data to be signed is:
* followed by everything so far placed in the
* outgoing packet.
*/
- sigdata_len = s->pktout->length - 5 + 4 + 20;
- if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
- sigdata_len -= 4;
+ sigdata_len = s->pktout->length - 5 + 4 +
+ ssh->v2_session_id_len;
+ if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
+ sigdata_len -= 4;
sigdata = snewn(sigdata_len, unsigned char);
- p = 0;
- if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
- PUT_32BIT(sigdata+p, 20);
- p += 4;
- }
- memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
+ p = 0;
+ if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
+ PUT_32BIT(sigdata+p, ssh->v2_session_id_len);
+ p += 4;
+ }
+ memcpy(sigdata+p, ssh->v2_session_id,
+ ssh->v2_session_id_len);
+ p += ssh->v2_session_id_len;
memcpy(sigdata+p, s->pktout->data + 5,
s->pktout->length - 5);
- p += s->pktout->length - 5;
- assert(p == sigdata_len);
+ p += s->pktout->length - 5;
+ assert(p == sigdata_len);
sigblob = key->alg->sign(key->data, (char *)sigdata,
sigdata_len, &sigblob_len);
ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
s->type = AUTH_TYPE_PUBLICKEY;
key->alg->freekey(key->data);
}
- } else if (s->method == AUTH_PASSWORD) {
+
+ } else if (s->can_keyb_inter && !s->kbd_inter_refused) {
+
+ /*
+ * Keyboard-interactive authentication.
+ */
+
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+
+ ssh->pkt_actx = SSH2_PKTCTX_KBDINTER;
+
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "keyboard-interactive");
+ /* method */
+ ssh2_pkt_addstring(s->pktout, ""); /* lang */
+ ssh2_pkt_addstring(s->pktout, ""); /* submethods */
+ ssh2_pkt_send(ssh, s->pktout);
+
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
+ /* Server is not willing to do keyboard-interactive
+ * at all (or, bizarrely but legally, accepts the
+ * user without actually issuing any prompts).
+ * Give up on it entirely. */
+ s->gotit = TRUE;
+ if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
+ logevent("Keyboard-interactive authentication refused");
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
+ s->kbd_inter_refused = TRUE; /* don't try it again */
+ continue;
+ }
+
+ /*
+ * Loop while the server continues to send INFO_REQUESTs.
+ */
+ while (pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
+
+ char *name, *inst, *lang;
+ int name_len, inst_len, lang_len;
+ int i;
+
+ /*
+ * We've got a fresh USERAUTH_INFO_REQUEST.
+ * Get the preamble and start building a prompt.
+ */
+ ssh_pkt_getstring(pktin, &name, &name_len);
+ ssh_pkt_getstring(pktin, &inst, &inst_len);
+ ssh_pkt_getstring(pktin, &lang, &lang_len);
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ if (name_len) {
+ /* FIXME: better prefix to distinguish from
+ * local prompts? */
+ s->cur_prompt->name =
+ dupprintf("SSH server: %.*s", name_len, name);
+ s->cur_prompt->name_reqd = TRUE;
+ } else {
+ s->cur_prompt->name =
+ dupstr("SSH server authentication");
+ s->cur_prompt->name_reqd = FALSE;
+ }
+ /* FIXME: ugly to print "Using..." in prompt _every_
+ * time round. Can this be done more subtly? */
+ s->cur_prompt->instruction =
+ dupprintf("Using keyboard-interactive authentication.%s%.*s",
+ inst_len ? "\n" : "", inst_len, inst);
+ s->cur_prompt->instr_reqd = TRUE;
+
+ /*
+ * Get the prompts from the packet.
+ */
+ s->num_prompts = ssh_pkt_getuint32(pktin);
+ for (i = 0; i < s->num_prompts; i++) {
+ char *prompt;
+ int prompt_len;
+ int echo;
+ static char noprompt[] =
+ "<server failed to send prompt>: ";
+
+ ssh_pkt_getstring(pktin, &prompt, &prompt_len);
+ echo = ssh2_pkt_getbool(pktin);
+ if (!prompt_len) {
+ prompt = noprompt;
+ prompt_len = lenof(noprompt)-1;
+ }
+ add_prompt(s->cur_prompt,
+ dupprintf("%.*s", prompt_len, prompt),
+ echo, SSH_MAX_PASSWORD_LEN);
+ }
+
+ /*
+ * Get the user's responses.
+ */
+ if (s->num_prompts) {
+ int ret; /* not live over crReturn */
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /*
+ * Failed to get responses. Terminate.
+ */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate",
+ SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
+ TRUE);
+ crStopV;
+ }
+ }
+
+ /*
+ * Send the responses to the server.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
+ ssh2_pkt_adduint32(s->pktout, s->num_prompts);
+ for (i=0; i < s->num_prompts; i++) {
+ dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
+ ssh2_pkt_addstring(s->pktout,
+ s->cur_prompt->prompts[i]->result);
+ end_log_omission(ssh, s->pktout);
+ }
+ ssh2_pkt_send_with_padding(ssh, s->pktout, 256);
+
+ /*
+ * Get the next packet in case it's another
+ * INFO_REQUEST.
+ */
+ crWaitUntilV(pktin);
+
+ }
+
+ /*
+ * We should have SUCCESS or FAILURE now.
+ */
+ s->gotit = TRUE;
+
+ } else if (s->can_passwd) {
+
+ /*
+ * Plain old password authentication.
+ */
+ int ret; /* not live over crReturn */
+ int changereq_first_time; /* not live over crReturn */
+
+ ssh->pkt_actx = SSH2_PKTCTX_PASSWORD;
+
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH password");
+ add_prompt(s->cur_prompt, dupprintf("%.90s@%.90s's password: ",
+ s->username,
+ ssh->savedhost),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /*
+ * Failed to get responses. Terminate.
+ */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate",
+ SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
+ TRUE);
+ crStopV;
+ }
+ /*
+ * Squirrel away the password. (We may need it later if
+ * asked to change it.)
+ */
+ s->password = dupstr(s->cur_prompt->prompts[0]->result);
+ free_prompts(s->cur_prompt);
+
/*
+ * Send the password packet.
+ *
* We pad out the password packet to 256 bytes to make
* it harder for an attacker to find the length of the
* user's password.
* people who find out how long their password is!
*/
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- s->pktout->forcepad = 256;
ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
ssh2_pkt_addstring(s->pktout, "password");
ssh2_pkt_addbool(s->pktout, FALSE);
dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
ssh2_pkt_addstring(s->pktout, s->password);
- memset(s->password, 0, sizeof(s->password));
end_log_omission(ssh, s->pktout);
- ssh2_pkt_send(ssh, s->pktout);
+ ssh2_pkt_send_with_padding(ssh, s->pktout, 256);
logevent("Sent password");
s->type = AUTH_TYPE_PASSWORD;
- } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
- if (s->curr_prompt == 0) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
- s->pktout->forcepad = 256;
- ssh2_pkt_adduint32(s->pktout, s->num_prompts);
- }
- if (s->need_pw) { /* only add pw if we just got one! */
+
+ /*
+ * Wait for next packet, in case it's a password change
+ * request.
+ */
+ crWaitUntilV(pktin);
+ changereq_first_time = TRUE;
+
+ while (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
+
+ /*
+ * We're being asked for a new password
+ * (perhaps not for the first time).
+ * Loop until the server accepts it.
+ */
+
+ int got_new = FALSE; /* not live over crReturn */
+ char *prompt; /* not live over crReturn */
+ int prompt_len; /* not live over crReturn */
+
+ {
+ char *msg;
+ if (changereq_first_time)
+ msg = "Server requested password change";
+ else
+ msg = "Server rejected new password";
+ logevent(msg);
+ c_write_str(ssh, msg);
+ c_write_str(ssh, "\r\n");
+ }
+
+ ssh_pkt_getstring(pktin, &prompt, &prompt_len);
+
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("New SSH password");
+ s->cur_prompt->instruction =
+ dupprintf("%.*s", prompt_len, prompt);
+ s->cur_prompt->instr_reqd = TRUE;
+ /*
+ * There's no explicit requirement in the protocol
+ * for the "old" passwords in the original and
+ * password-change messages to be the same, and
+ * apparently some Cisco kit supports password change
+ * by the user entering a blank password originally
+ * and the real password subsequently, so,
+ * reluctantly, we prompt for the old password again.
+ *
+ * (On the other hand, some servers don't even bother
+ * to check this field.)
+ */
+ add_prompt(s->cur_prompt,
+ dupstr("Current password (blank for previously entered password): "),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+ add_prompt(s->cur_prompt, dupstr("Enter new password: "),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+ add_prompt(s->cur_prompt, dupstr("Confirm new password: "),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+
+ /*
+ * Loop until the user manages to enter the same
+ * password twice.
+ */
+ while (!got_new) {
+
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /*
+ * Failed to get responses. Terminate.
+ */
+ /* burn the evidence */
+ free_prompts(s->cur_prompt);
+ memset(s->password, 0, strlen(s->password));
+ sfree(s->password);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate",
+ SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
+ TRUE);
+ crStopV;
+ }
+
+ /*
+ * If the user specified a new original password
+ * (IYSWIM), overwrite any previously specified
+ * one.
+ * (A side effect is that the user doesn't have to
+ * re-enter it if they louse up the new password.)
+ */
+ if (s->cur_prompt->prompts[0]->result[0]) {
+ memset(s->password, 0, strlen(s->password));
+ /* burn the evidence */
+ sfree(s->password);
+ s->password =
+ dupstr(s->cur_prompt->prompts[0]->result);
+ }
+
+ /*
+ * Check the two new passwords match.
+ */
+ got_new = (strcmp(s->cur_prompt->prompts[1]->result,
+ s->cur_prompt->prompts[2]->result)
+ == 0);
+ if (!got_new)
+ /* They don't. Silly user. */
+ c_write_str(ssh, "Passwords do not match\r\n");
+
+ }
+
+ /*
+ * Send the new password (along with the old one).
+ * (see above for padding rationale)
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "password");
+ ssh2_pkt_addbool(s->pktout, TRUE);
dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
ssh2_pkt_addstring(s->pktout, s->password);
- memset(s->password, 0, sizeof(s->password));
+ ssh2_pkt_addstring(s->pktout,
+ s->cur_prompt->prompts[1]->result);
+ free_prompts(s->cur_prompt);
end_log_omission(ssh, s->pktout);
- s->curr_prompt++;
- }
- if (s->curr_prompt >= s->num_prompts) {
- ssh2_pkt_send(ssh, s->pktout);
- } else {
+ ssh2_pkt_send_with_padding(ssh, s->pktout, 256);
+ logevent("Sent new password");
+
/*
- * If there are prompts remaining, we set
- * `gotit' so that we won't attempt to get
- * another packet. Then we go back round the
- * loop and will end up retrieving another
- * prompt out of the existing packet. Funky or
- * what?
+ * Now see what the server has to say about it.
+ * (If it's CHANGEREQ again, it's not happy with the
+ * new password.)
*/
- s->gotit = TRUE;
+ crWaitUntilV(pktin);
+ changereq_first_time = FALSE;
+
}
- s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+
+ /*
+ * We need to reexamine the current pktin at the top
+ * of the loop. Either:
+ * - we weren't asked to change password at all, in
+ * which case it's a SUCCESS or FAILURE with the
+ * usual meaning
+ * - we sent a new password, and the server was
+ * either OK with it (SUCCESS or FAILURE w/partial
+ * success) or unhappy with the _old_ password
+ * (FAILURE w/o partial success)
+ * In any of these cases, we go back to the top of
+ * the loop and start again.
+ */
+ s->gotit = TRUE;
+
+ /*
+ * We don't need the old password any more, in any
+ * case. Burn the evidence.
+ */
+ memset(s->password, 0, strlen(s->password));
+ sfree(s->password);
+
} else {
- c_write_str(ssh, "No supported authentication methods"
- " left to try!\r\n");
- logevent("No supported authentications offered."
- " Disconnecting");
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "No supported authentication"
- " methods available");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
- ssh->close_expected = TRUE;
- ssh_closing((Plug)ssh, NULL, 0, 0);
+
+ ssh_disconnect(ssh, NULL,
+ "No supported authentication methods available",
+ SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE,
+ FALSE);
crStopV;
+
}
+
}
}
ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
+ /* Clear up various bits and pieces from authentication. */
+ if (s->publickey_blob) {
+ sfree(s->publickey_blob);
+ sfree(s->publickey_comment);
+ }
+ if (s->agent_response)
+ sfree(s->agent_response);
+
/*
* Now the connection protocol has started, one way or another.
*/
/*
* Create the main session channel.
*/
- if (!ssh->cfg.ssh_no_shell) {
+ if (ssh->cfg.ssh_no_shell) {
+ ssh->mainchan = NULL;
+ } else if (*ssh->cfg.ssh_nc_host) {
+ /*
+ * Just start a direct-tcpip channel and use it as the main
+ * channel.
+ */
+ ssh->mainchan = snew(struct ssh_channel);
+ ssh->mainchan->ssh = ssh;
+ ssh->mainchan->localid = alloc_channel_id(ssh);
+ logeventf(ssh,
+ "Opening direct-tcpip channel to %s:%d in place of session",
+ ssh->cfg.ssh_nc_host, ssh->cfg.ssh_nc_port);
+ s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
+ ssh2_pkt_addstring(s->pktout, "direct-tcpip");
+ ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
+ ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
+ ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
+ ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT); /* our max pkt size */
+ ssh2_pkt_addstring(s->pktout, ssh->cfg.ssh_nc_host);
+ ssh2_pkt_adduint32(s->pktout, ssh->cfg.ssh_nc_port);
+ /*
+ * There's nothing meaningful to put in the originator
+ * fields, but some servers insist on syntactically correct
+ * information.
+ */
+ ssh2_pkt_addstring(s->pktout, "0.0.0.0");
+ ssh2_pkt_adduint32(s->pktout, 0);
+ ssh2_pkt_send(ssh, s->pktout);
+
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
+ bombout(("Server refused to open a direct-tcpip channel"));
+ crStopV;
+ /* FIXME: error data comes back in FAILURE packet */
+ }
+ if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
+ bombout(("Server's channel confirmation cited wrong channel"));
+ crStopV;
+ }
+ ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
+ ssh->mainchan->halfopen = FALSE;
+ ssh->mainchan->type = CHAN_MAINSESSION;
+ ssh->mainchan->closes = 0;
+ ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
+ ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
+ bufchain_init(&ssh->mainchan->v.v2.outbuffer);
+ add234(ssh->channels, ssh->mainchan);
+ update_specials_menu(ssh->frontend);
+ logevent("Opened direct-tcpip channel");
+ ssh->ncmode = TRUE;
+ } else {
ssh->mainchan = snew(struct ssh_channel);
ssh->mainchan->ssh = ssh;
ssh->mainchan->localid = alloc_channel_id(ssh);
add234(ssh->channels, ssh->mainchan);
update_specials_menu(ssh->frontend);
logevent("Opened channel for session");
- } else
- ssh->mainchan = NULL;
+ ssh->ncmode = FALSE;
+ }
/*
* Now we have a channel, make dispatch table entries for
/*
* Potentially enable X11 forwarding.
*/
- if (ssh->mainchan && ssh->cfg.x11_forward) {
+ if (ssh->mainchan && !ssh->ncmode && ssh->cfg.x11_forward) {
char proto[20], data[64];
logevent("Requesting X11 forwarding");
ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
/*
* Potentially enable agent forwarding.
*/
- if (ssh->mainchan && ssh->cfg.agentfwd && agent_exists()) {
+ if (ssh->mainchan && !ssh->ncmode && ssh->cfg.agentfwd && agent_exists()) {
logevent("Requesting OpenSSH-style agent forwarding");
s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
/*
* Now allocate a pty for the session.
*/
- if (ssh->mainchan && !ssh->cfg.nopty) {
+ if (ssh->mainchan && !ssh->ncmode && !ssh->cfg.nopty) {
/* Unpick the terminal-speed string. */
/* XXX perhaps we should allow no speeds to be sent. */
ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
* Simplest thing here is to send all the requests at once, and
* then wait for a whole bunch of successes or failures.
*/
- if (ssh->mainchan && *ssh->cfg.environmt) {
+ if (ssh->mainchan && !ssh->ncmode && *ssh->cfg.environmt) {
char *e = ssh->cfg.environmt;
char *var, *varend, *val;
* this twice if the config data has provided a second choice
* of command.
*/
- if (ssh->mainchan) while (1) {
+ if (ssh->mainchan && !ssh->ncmode) while (1) {
int subsys;
char *cmd;
ssh->hostkey = NULL;
ssh->exitcode = -1;
ssh->close_expected = FALSE;
+ ssh->clean_exit = FALSE;
ssh->state = SSH_STATE_PREPACKET;
ssh->size_needed = FALSE;
ssh->eof_needed = FALSE;
ssh->deferred_len = 0;
ssh->deferred_size = 0;
ssh->fallback_cmd = 0;
- ssh->pkt_ctx = 0;
+ ssh->pkt_kctx = SSH2_PKTCTX_NOKEX;
+ ssh->pkt_actx = SSH2_PKTCTX_NOAUTH;
ssh->x11auth = NULL;
ssh->v1_compressing = FALSE;
ssh->v2_outgoing_sequence = 0;
ssh->do_ssh1_login_state = NULL;
ssh->do_ssh2_transport_state = NULL;
ssh->do_ssh2_authconn_state = NULL;
+ ssh->v_c = NULL;
+ ssh->v_s = NULL;
ssh->mainchan = NULL;
ssh->throttled_all = 0;
ssh->v1_stdout_throttling = 0;
sfree(ssh->do_ssh1_login_state);
sfree(ssh->do_ssh2_transport_state);
sfree(ssh->do_ssh2_authconn_state);
+ sfree(ssh->v_c);
+ sfree(ssh->v_s);
if (ssh->crcda_ctx) {
crcda_free_context(ssh->crcda_ctx);
ssh->crcda_ctx = NULL;
unsigned long old_max_data_size;
pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
- ssh_setup_portfwd(ssh, cfg);
+ if (ssh->portfwds)
+ ssh_setup_portfwd(ssh, cfg);
if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
cfg->ssh_rekey_time != 0) {
}
/*
- * Called to send data down the Telnet connection.
+ * Called to send data down the SSH connection.
*/
static int ssh_send(void *handle, char *buf, int len)
{
}
/*
- * Send Telnet special codes. TS_EOF is useful for `plink', so you
+ * Send special codes. TS_EOF is useful for `plink', so you
* can send an EOF and collect resulting output (e.g. `plink
* hostname sort').
*/
ssh1_throttle(ssh, -1);
}
} else {
- if (ssh->mainchan && ssh->mainchan->closes == 0)
- ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
+ ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
}
}
* too much hassle to keep track, and partly I'm not
* convinced the server should be told details like that
* about my local network configuration.
+ * The "originator IP address" is syntactically a numeric
+ * IP address, and some servers (e.g., Tectia) get upset
+ * if it doesn't match this syntax.
*/
- ssh2_pkt_addstring(pktout, "client-side-connection");
+ ssh2_pkt_addstring(pktout, "0.0.0.0");
ssh2_pkt_adduint32(pktout, 0);
ssh2_pkt_send(ssh, pktout);
}
}
-static Socket ssh_socket(void *handle)
+static int ssh_connected(void *handle)
{
Ssh ssh = (Ssh) handle;
- return ssh->s;
+ return ssh->s != NULL;
}
static int ssh_sendok(void *handle)
if (ssh->s != NULL)
return -1;
else
- return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
+ return (ssh->exitcode >= 0 ? ssh->exitcode : INT_MAX);
}
/*
ssh_size,
ssh_special,
ssh_get_specials,
- ssh_socket,
+ ssh_connected,
ssh_return_exitcode,
ssh_sendok,
ssh_ldisc,
ssh_provide_logctx,
ssh_unthrottle,
ssh_cfg_info,
+ "ssh",
+ PROT_SSH,
22
};