Vendor import of OpenSSH.

1 files changed, 578 insertions, 0 deletions

diff --git a/crypto/openssh/authfd.c b/crypto/openssh/authfd.c
new file mode 100644
index 0000000..6a9ec6b
--- /dev/null
+++ b/crypto/openssh/authfd.c
@@ -0,0 +1,578 @@
+/*
+ * 
+ * authfd.c
+ * 
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * 
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * 
+ * Created: Wed Mar 29 01:30:28 1995 ylo
+ * 
+ * Functions for connecting the local authentication agent.
+ * 
+ */
+
+#include "includes.h"
+RCSID("$Id: authfd.c,v 1.16 1999/12/15 19:43:10 markus Exp $");
+
+#include "ssh.h"
+#include "rsa.h"
+#include "authfd.h"
+#include "buffer.h"
+#include "bufaux.h"
+#include "xmalloc.h"
+#include "getput.h"
+
+#include <ssl/rsa.h>
+
+/* Returns the number of the authentication fd, or -1 if there is none. */
+
+int
+ssh_get_authentication_socket()
+{
+	const char *authsocket;
+	int sock;
+	struct sockaddr_un sunaddr;
+
+	authsocket = getenv(SSH_AUTHSOCKET_ENV_NAME);
+	if (!authsocket)
+		return -1;
+
+	sunaddr.sun_family = AF_UNIX;
+	strlcpy(sunaddr.sun_path, authsocket, sizeof(sunaddr.sun_path));
+
+	sock = socket(AF_UNIX, SOCK_STREAM, 0);
+	if (sock < 0)
+		return -1;
+
+	/* close on exec */
+	if (fcntl(sock, F_SETFD, 1) == -1) {
+		close(sock);
+		return -1;
+	}
+	if (connect(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
+		close(sock);
+		return -1;
+	}
+	return sock;
+}
+
+/*
+ * Closes the agent socket if it should be closed (depends on how it was
+ * obtained).  The argument must have been returned by
+ * ssh_get_authentication_socket().
+ */
+
+void 
+ssh_close_authentication_socket(int sock)
+{
+	if (getenv(SSH_AUTHSOCKET_ENV_NAME))
+		close(sock);
+}
+
+/*
+ * Opens and connects a private socket for communication with the
+ * authentication agent.  Returns the file descriptor (which must be
+ * shut down and closed by the caller when no longer needed).
+ * Returns NULL if an error occurred and the connection could not be
+ * opened.
+ */
+
+AuthenticationConnection *
+ssh_get_authentication_connection()
+{
+	AuthenticationConnection *auth;
+	int sock;
+
+	sock = ssh_get_authentication_socket();
+
+	/*
+	 * Fail if we couldn't obtain a connection.  This happens if we
+	 * exited due to a timeout.
+	 */
+	if (sock < 0)
+		return NULL;
+
+	auth = xmalloc(sizeof(*auth));
+	auth->fd = sock;
+	buffer_init(&auth->packet);
+	buffer_init(&auth->identities);
+	auth->howmany = 0;
+
+	return auth;
+}
+
+/*
+ * Closes the connection to the authentication agent and frees any associated
+ * memory.
+ */
+
+void 
+ssh_close_authentication_connection(AuthenticationConnection *ac)
+{
+	buffer_free(&ac->packet);
+	buffer_free(&ac->identities);
+	close(ac->fd);
+	xfree(ac);
+}
+
+/*
+ * Returns the first authentication identity held by the agent.
+ * Returns true if an identity is available, 0 otherwise.
+ * The caller must initialize the integers before the call, and free the
+ * comment after a successful call (before calling ssh_get_next_identity).
+ */
+
+int
+ssh_get_first_identity(AuthenticationConnection *auth,
+		       BIGNUM *e, BIGNUM *n, char **comment)
+{
+	unsigned char msg[8192];
+	int len, l;
+
+	/*
+	 * Send a message to the agent requesting for a list of the
+	 * identities it can represent.
+	 */
+	msg[0] = 0;
+	msg[1] = 0;
+	msg[2] = 0;
+	msg[3] = 1;
+	msg[4] = SSH_AGENTC_REQUEST_RSA_IDENTITIES;
+	if (atomicio(write, auth->fd, msg, 5) != 5) {
+		error("write auth->fd: %.100s", strerror(errno));
+		return 0;
+	}
+	/* Read the length of the response.  XXX implement timeouts here. */
+	len = 4;
+	while (len > 0) {
+		l = read(auth->fd, msg + 4 - len, len);
+		if (l <= 0) {
+			error("read auth->fd: %.100s", strerror(errno));
+			return 0;
+		}
+		len -= l;
+	}
+
+	/*
+	 * Extract the length, and check it for sanity.  (We cannot trust
+	 * authentication agents).
+	 */
+	len = GET_32BIT(msg);
+	if (len < 1 || len > 256 * 1024)
+		fatal("Authentication reply message too long: %d\n", len);
+
+	/* Read the packet itself. */
+	buffer_clear(&auth->identities);
+	while (len > 0) {
+		l = len;
+		if (l > sizeof(msg))
+			l = sizeof(msg);
+		l = read(auth->fd, msg, l);
+		if (l <= 0)
+			fatal("Incomplete authentication reply.");
+		buffer_append(&auth->identities, (char *) msg, l);
+		len -= l;
+	}
+
+	/* Get message type, and verify that we got a proper answer. */
+	buffer_get(&auth->identities, (char *) msg, 1);
+	if (msg[0] != SSH_AGENT_RSA_IDENTITIES_ANSWER)
+		fatal("Bad authentication reply message type: %d", msg[0]);
+
+	/* Get the number of entries in the response and check it for sanity. */
+	auth->howmany = buffer_get_int(&auth->identities);
+	if (auth->howmany > 1024)
+		fatal("Too many identities in authentication reply: %d\n", auth->howmany);
+
+	/* Return the first entry (if any). */
+	return ssh_get_next_identity(auth, e, n, comment);
+}
+
+/*
+ * Returns the next authentication identity for the agent.  Other functions
+ * can be called between this and ssh_get_first_identity or two calls of this
+ * function.  This returns 0 if there are no more identities.  The caller
+ * must free comment after a successful return.
+ */
+
+int
+ssh_get_next_identity(AuthenticationConnection *auth,
+		      BIGNUM *e, BIGNUM *n, char **comment)
+{
+	unsigned int bits;
+
+	/* Return failure if no more entries. */
+	if (auth->howmany <= 0)
+		return 0;
+
+	/*
+	 * Get the next entry from the packet.  These will abort with a fatal
+	 * error if the packet is too short or contains corrupt data.
+	 */
+	bits = buffer_get_int(&auth->identities);
+	buffer_get_bignum(&auth->identities, e);
+	buffer_get_bignum(&auth->identities, n);
+	*comment = buffer_get_string(&auth->identities, NULL);
+
+	if (bits != BN_num_bits(n))
+		error("Warning: identity keysize mismatch: actual %d, announced %u",
+		      BN_num_bits(n), bits);
+
+	/* Decrement the number of remaining entries. */
+	auth->howmany--;
+
+	return 1;
+}
+
+/*
+ * Generates a random challenge, sends it to the agent, and waits for
+ * response from the agent.  Returns true (non-zero) if the agent gave the
+ * correct answer, zero otherwise.  Response type selects the style of
+ * response desired, with 0 corresponding to protocol version 1.0 (no longer
+ * supported) and 1 corresponding to protocol version 1.1.
+ */
+
+int
+ssh_decrypt_challenge(AuthenticationConnection *auth,
+		      BIGNUM* e, BIGNUM *n, BIGNUM *challenge,
+		      unsigned char session_id[16],
+		      unsigned int response_type,
+		      unsigned char response[16])
+{
+	Buffer buffer;
+	unsigned char buf[8192];
+	int len, l, i;
+
+	/* Response type 0 is no longer supported. */
+	if (response_type == 0)
+		fatal("Compatibility with ssh protocol version 1.0 no longer supported.");
+
+	/* Format a message to the agent. */
+	buf[0] = SSH_AGENTC_RSA_CHALLENGE;
+	buffer_init(&buffer);
+	buffer_append(&buffer, (char *) buf, 1);
+	buffer_put_int(&buffer, BN_num_bits(n));
+	buffer_put_bignum(&buffer, e);
+	buffer_put_bignum(&buffer, n);
+	buffer_put_bignum(&buffer, challenge);
+	buffer_append(&buffer, (char *) session_id, 16);
+	buffer_put_int(&buffer, response_type);
+
+	/* Get the length of the message, and format it in the buffer. */
+	len = buffer_len(&buffer);
+	PUT_32BIT(buf, len);
+
+	/* Send the length and then the packet to the agent. */
+	if (atomicio(write, auth->fd, buf, 4) != 4 ||
+	    atomicio(write, auth->fd, buffer_ptr(&buffer),
+	    buffer_len(&buffer)) != buffer_len(&buffer)) {
+		error("Error writing to authentication socket.");
+error_cleanup:
+		buffer_free(&buffer);
+		return 0;
+	}
+	/*
+	 * Wait for response from the agent.  First read the length of the
+	 * response packet.
+	 */
+	len = 4;
+	while (len > 0) {
+		l = read(auth->fd, buf + 4 - len, len);
+		if (l <= 0) {
+			error("Error reading response length from authentication socket.");
+			goto error_cleanup;
+		}
+		len -= l;
+	}
+
+	/* Extract the length, and check it for sanity. */
+	len = GET_32BIT(buf);
+	if (len > 256 * 1024)
+		fatal("Authentication response too long: %d", len);
+
+	/* Read the rest of the response in tothe buffer. */
+	buffer_clear(&buffer);
+	while (len > 0) {
+		l = len;
+		if (l > sizeof(buf))
+			l = sizeof(buf);
+		l = read(auth->fd, buf, l);
+		if (l <= 0) {
+			error("Error reading response from authentication socket.");
+			goto error_cleanup;
+		}
+		buffer_append(&buffer, (char *) buf, l);
+		len -= l;
+	}
+
+	/* Get the type of the packet. */
+	buffer_get(&buffer, (char *) buf, 1);
+
+	/* Check for agent failure message. */
+	if (buf[0] == SSH_AGENT_FAILURE) {
+		log("Agent admitted failure to authenticate using the key.");
+		goto error_cleanup;
+	}
+	/* Now it must be an authentication response packet. */
+	if (buf[0] != SSH_AGENT_RSA_RESPONSE)
+		fatal("Bad authentication response: %d", buf[0]);
+
+	/*
+	 * Get the response from the packet.  This will abort with a fatal
+	 * error if the packet is corrupt.
+	 */
+	for (i = 0; i < 16; i++)
+		response[i] = buffer_get_char(&buffer);
+
+	/* The buffer containing the packet is no longer needed. */
+	buffer_free(&buffer);
+
+	/* Correct answer. */
+	return 1;
+}
+
+/*
+ * Adds an identity to the authentication server.  This call is not meant to
+ * be used by normal applications.
+ */
+
+int 
+ssh_add_identity(AuthenticationConnection *auth,
+		 RSA * key, const char *comment)
+{
+	Buffer buffer;
+	unsigned char buf[8192];
+	int len, l, type;
+
+	/* Format a message to the agent. */
+	buffer_init(&buffer);
+	buffer_put_char(&buffer, SSH_AGENTC_ADD_RSA_IDENTITY);
+	buffer_put_int(&buffer, BN_num_bits(key->n));
+	buffer_put_bignum(&buffer, key->n);
+	buffer_put_bignum(&buffer, key->e);
+	buffer_put_bignum(&buffer, key->d);
+	/* To keep within the protocol: p < q for ssh. in SSL p > q */
+	buffer_put_bignum(&buffer, key->iqmp);	/* ssh key->u */
+	buffer_put_bignum(&buffer, key->q);	/* ssh key->p, SSL key->q */
+	buffer_put_bignum(&buffer, key->p);	/* ssh key->q, SSL key->p */
+	buffer_put_string(&buffer, comment, strlen(comment));
+
+	/* Get the length of the message, and format it in the buffer. */
+	len = buffer_len(&buffer);
+	PUT_32BIT(buf, len);
+
+	/* Send the length and then the packet to the agent. */
+	if (atomicio(write, auth->fd, buf, 4) != 4 ||
+	    atomicio(write, auth->fd, buffer_ptr(&buffer),
+	    buffer_len(&buffer)) != buffer_len(&buffer)) {
+		error("Error writing to authentication socket.");
+error_cleanup:
+		buffer_free(&buffer);
+		return 0;
+	}
+	/* Wait for response from the agent.  First read the length of the
+	   response packet. */
+	len = 4;
+	while (len > 0) {
+		l = read(auth->fd, buf + 4 - len, len);
+		if (l <= 0) {
+			error("Error reading response length from authentication socket.");
+			goto error_cleanup;
+		}
+		len -= l;
+	}
+
+	/* Extract the length, and check it for sanity. */
+	len = GET_32BIT(buf);
+	if (len > 256 * 1024)
+		fatal("Add identity response too long: %d", len);
+
+	/* Read the rest of the response in tothe buffer. */
+	buffer_clear(&buffer);
+	while (len > 0) {
+		l = len;
+		if (l > sizeof(buf))
+			l = sizeof(buf);
+		l = read(auth->fd, buf, l);
+		if (l <= 0) {
+			error("Error reading response from authentication socket.");
+			goto error_cleanup;
+		}
+		buffer_append(&buffer, (char *) buf, l);
+		len -= l;
+	}
+
+	/* Get the type of the packet. */
+	type = buffer_get_char(&buffer);
+	switch (type) {
+	case SSH_AGENT_FAILURE:
+		buffer_free(&buffer);
+		return 0;
+	case SSH_AGENT_SUCCESS:
+		buffer_free(&buffer);
+		return 1;
+	default:
+		fatal("Bad response to add identity from authentication agent: %d",
+		      type);
+	}
+	/* NOTREACHED */
+	return 0;
+}
+
+/*
+ * Removes an identity from the authentication server.  This call is not
+ * meant to be used by normal applications.
+ */
+
+int 
+ssh_remove_identity(AuthenticationConnection *auth, RSA *key)
+{
+	Buffer buffer;
+	unsigned char buf[8192];
+	int len, l, type;
+
+	/* Format a message to the agent. */
+	buffer_init(&buffer);
+	buffer_put_char(&buffer, SSH_AGENTC_REMOVE_RSA_IDENTITY);
+	buffer_put_int(&buffer, BN_num_bits(key->n));
+	buffer_put_bignum(&buffer, key->e);
+	buffer_put_bignum(&buffer, key->n);
+
+	/* Get the length of the message, and format it in the buffer. */
+	len = buffer_len(&buffer);
+	PUT_32BIT(buf, len);
+
+	/* Send the length and then the packet to the agent. */
+	if (atomicio(write, auth->fd, buf, 4) != 4 ||
+	    atomicio(write, auth->fd, buffer_ptr(&buffer),
+	    buffer_len(&buffer)) != buffer_len(&buffer)) {
+		error("Error writing to authentication socket.");
+error_cleanup:
+		buffer_free(&buffer);
+		return 0;
+	}
+	/*
+	 * Wait for response from the agent.  First read the length of the
+	 * response packet.
+	 */
+	len = 4;
+	while (len > 0) {
+		l = read(auth->fd, buf + 4 - len, len);
+		if (l <= 0) {
+			error("Error reading response length from authentication socket.");
+			goto error_cleanup;
+		}
+		len -= l;
+	}
+
+	/* Extract the length, and check it for sanity. */
+	len = GET_32BIT(buf);
+	if (len > 256 * 1024)
+		fatal("Remove identity response too long: %d", len);
+
+	/* Read the rest of the response in tothe buffer. */
+	buffer_clear(&buffer);
+	while (len > 0) {
+		l = len;
+		if (l > sizeof(buf))
+			l = sizeof(buf);
+		l = read(auth->fd, buf, l);
+		if (l <= 0) {
+			error("Error reading response from authentication socket.");
+			goto error_cleanup;
+		}
+		buffer_append(&buffer, (char *) buf, l);
+		len -= l;
+	}
+
+	/* Get the type of the packet. */
+	type = buffer_get_char(&buffer);
+	switch (type) {
+	case SSH_AGENT_FAILURE:
+		buffer_free(&buffer);
+		return 0;
+	case SSH_AGENT_SUCCESS:
+		buffer_free(&buffer);
+		return 1;
+	default:
+		fatal("Bad response to remove identity from authentication agent: %d",
+		      type);
+	}
+	/* NOTREACHED */
+	return 0;
+}
+
+/*
+ * Removes all identities from the agent.  This call is not meant to be used
+ * by normal applications.
+ */
+
+int 
+ssh_remove_all_identities(AuthenticationConnection *auth)
+{
+	Buffer buffer;
+	unsigned char buf[8192];
+	int len, l, type;
+
+	/* Get the length of the message, and format it in the buffer. */
+	PUT_32BIT(buf, 1);
+	buf[4] = SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES;
+
+	/* Send the length and then the packet to the agent. */
+	if (atomicio(write, auth->fd, buf, 5) != 5) {
+		error("Error writing to authentication socket.");
+		return 0;
+	}
+	/*
+	 * Wait for response from the agent.  First read the length of the
+	 * response packet.
+	 */
+	len = 4;
+	while (len > 0) {
+		l = read(auth->fd, buf + 4 - len, len);
+		if (l <= 0) {
+			error("Error reading response length from authentication socket.");
+			return 0;
+		}
+		len -= l;
+	}
+
+	/* Extract the length, and check it for sanity. */
+	len = GET_32BIT(buf);
+	if (len > 256 * 1024)
+		fatal("Remove identity response too long: %d", len);
+
+	/* Read the rest of the response into the buffer. */
+	buffer_init(&buffer);
+	while (len > 0) {
+		l = len;
+		if (l > sizeof(buf))
+			l = sizeof(buf);
+		l = read(auth->fd, buf, l);
+		if (l <= 0) {
+			error("Error reading response from authentication socket.");
+			buffer_free(&buffer);
+			return 0;
+		}
+		buffer_append(&buffer, (char *) buf, l);
+		len -= l;
+	}
+
+	/* Get the type of the packet. */
+	type = buffer_get_char(&buffer);
+	switch (type) {
+	case SSH_AGENT_FAILURE:
+		buffer_free(&buffer);
+		return 0;
+	case SSH_AGENT_SUCCESS:
+		buffer_free(&buffer);
+		return 1;
+	default:
+		fatal("Bad response to remove identity from authentication agent: %d",
+		      type);
+	}
+	/* NOTREACHED */
+	return 0;
+}