X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/putty/blobdiff_plain/edd0cb8aef57080ae884e06731a7892ca8cdba44..b8e3173d5169da33af5b41fa3b8e5b482bfdc6dc:/ssh.c?ds=sidebyside

diff --git a/ssh.c b/ssh.c
index 45ecf260..1e228446 100644
--- a/ssh.c
+++ b/ssh.c
@@ -3459,9 +3459,10 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
 		    break;	       /* go and try something else */
 		} else if (ret == -1) {
 		    c_write_str(ssh, "Wrong passphrase.\r\n"); /* FIXME */
-		    s->tried_publickey = 0;
 		    got_passphrase = FALSE;
 		    /* and try again */
+		} else {
+		    assert(0 && "unexpected return from loadrsakey()");
 		}
 	    }
 
@@ -3476,7 +3477,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
 		crWaitUntil(pktin);
 		if (pktin->type == SSH1_SMSG_FAILURE) {
 		    c_write_str(ssh, "Server refused our public key.\r\n");
-		    continue;	       /* go and try password */
+		    continue;	       /* go and try something else */
 		}
 		if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
 		    bombout(("Bizarre response to offer of public key"));
@@ -3516,7 +3517,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
 		    if (flags & FLAG_VERBOSE)
 			c_write_str(ssh, "Failed to authenticate with"
 				    " our public key.\r\n");
-		    continue;	       /* go and try password */
+		    continue;	       /* go and try something else */
 		} else if (pktin->type != SSH1_SMSG_SUCCESS) {
 		    bombout(("Bizarre response to RSA authentication response"));
 		    crStop(0);
@@ -6474,11 +6475,6 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 {
     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,
@@ -6495,6 +6491,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 	prompts_t *cur_prompt;
 	int num_prompts;
 	char username[100];
+	char *password;
 	int got_username;
 	void *publickey_blob;
 	int publickey_bloblen;
@@ -6731,13 +6728,9 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 		break;
 	    }
 
-	    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;
 	    }
 
@@ -7016,7 +7009,6 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 		    s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
 		    continue; /* process this new message */
 		}
-		s->method = AUTH_PUBLICKEY_FILE;
 		logevent("Offer of public key accepted");
 
 		/*
@@ -7161,11 +7153,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 		/*
 		 * Keyboard-interactive authentication.
 		 */
-		char *name, *inst, *lang;
-		int name_len, inst_len, lang_len;
-		int i;
 
-		s->method = AUTH_KEYBOARD_INTERACTIVE;
 		s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
 
 		ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
@@ -7184,7 +7172,9 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 		crWaitUntilV(pktin);
 		if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
 		    /* Server is not willing to do keyboard-interactive
-		     * at all. Give up on it entirely. */
+		     * 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");
@@ -7194,89 +7184,113 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 		}
 
 		/*
-		 * We've got a fresh USERAUTH_INFO_REQUEST.
-		 * Get the preamble and start building a prompt.
+		 * Loop while the server continues to send INFO_REQUESTs.
 		 */
-		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;
-		}
-		s->cur_prompt->instruction =
-		    dupprintf("Using keyboard-interactive authentication.%s%.*s",
-			      inst_len ? "\n" : "", inst_len, inst);
-		s->cur_prompt->instr_reqd = TRUE;
+		while (pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
 
-		/*
-		 * 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>: ";
+		    char *name, *inst, *lang;
+		    int name_len, inst_len, lang_len;
+		    int i;
 
-		    ssh_pkt_getstring(pktin, &prompt, &prompt_len);
-		    echo = ssh2_pkt_getbool(pktin);
-		    if (!prompt_len) {
-			prompt = noprompt;
-			prompt_len = lenof(noprompt)-1;
+		    /*
+		     * 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;
 		    }
-		    add_prompt(s->cur_prompt,
-			       dupprintf("%.*s", prompt_len, prompt),
-			       echo, SSH_MAX_PASSWORD_LEN);
-		}
+		    /* 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 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;
+		    /*
+		     * 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);
 		    }
-		    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;
+
+		    /*
+		     * 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);
+		    s->pktout->forcepad = 256;
+		    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(ssh, s->pktout);
+
+		    /*
+		     * Get the next packet in case it's another
+		     * INFO_REQUEST.
+		     */
+		    crWaitUntilV(pktin);
+
 		}
 
 		/*
-		 * Send the responses to the server.
+		 * We should have SUCCESS or FAILURE now.
 		 */
-		s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
-		s->pktout->forcepad = 256;
-		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(ssh, s->pktout);
-		s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE; /*FIXME?*/
+		s->gotit = TRUE;
 
 	    } else if (s->can_passwd) {
 
@@ -7284,8 +7298,8 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 		 * Plain old password authentication.
 		 */
 		int ret; /* not live over crReturn */
+		int changereq_first_time; /* not live over crReturn */
 
-		s->method = AUTH_PASSWORD;
 		ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
 		ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
 
@@ -7314,6 +7328,12 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 				   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.
@@ -7334,13 +7354,145 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
 		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->cur_prompt->prompts[0]->result);
-		free_prompts(s->cur_prompt);
+		ssh2_pkt_addstring(s->pktout, s->password);
 		end_log_omission(ssh, s->pktout);
 		ssh2_pkt_send(ssh, s->pktout);
 		logevent("Sent password");
-		s->type = AUTH_TYPE_PASSWORD; /*FIXME?*/
+		s->type = AUTH_TYPE_PASSWORD;
+
+		/*
+		 * 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;
+		    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;
+			}
+
+			/*
+			 * Check the two passwords match.
+			 */
+			got_new = (strcmp(s->cur_prompt->prompts[0]->result,
+					  s->cur_prompt->prompts[1]->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);
+		    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, "password");
+		    ssh2_pkt_addbool(s->pktout, TRUE);
+		    dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
+		    ssh2_pkt_addstring(s->pktout, s->password);
+		    ssh2_pkt_addstring(s->pktout,
+				       s->cur_prompt->prompts[0]->result);
+		    free_prompts(s->cur_prompt);
+		    end_log_omission(ssh, s->pktout);
+		    ssh2_pkt_send(ssh, s->pktout);
+		    logevent("Sent new password");
+		    
+		    /*
+		     * Now see what the server has to say about it.
+		     * (If it's CHANGEREQ again, it's not happy with the
+		     * new password.)
+		     */
+		    crWaitUntilV(pktin);
+		    changereq_first_time = FALSE;
+
+		}
+
+		/*
+		 * 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 {