- Merged very large OpenBSD source code reformat

 - OpenBSD CVS updates
   - [channels.c cipher.c compat.c log-client.c scp.c serverloop.c]
     [ssh.h sshd.8 sshd.c]
     syslog changes:
     * Unified Logmessage for all auth-types, for success and for failed
     * Standard connections get only ONE line in the LOG when level==LOG:
       Auth-attempts are logged only, if authentication is:
          a) successfull or
          b) with passwd or
          c) we had more than AUTH_FAIL_LOG failues
     * many log() became verbose()
     * old behaviour with level=VERBOSE
   - [readconf.c readconf.h ssh.1 ssh.h sshconnect.c sshd.c]
     tranfer s/key challenge/response data in SSH_SMSG_AUTH_TIS_CHALLENGE
     messages. allows use of s/key in windows (ttssh, securecrt) and
     ssh-1.2.27 clients without 'ssh -v', ok: niels@
   - [sshd.8]
     -V, for fallback to openssh in SSH2 compatibility mode
   - [sshd.c]
     fix sigchld race; cjc5@po.cwru.edu

1 files changed, 536 insertions, 588 deletions

diff --git a/ssh-agent.c b/ssh-agent.c
index f1ceb569..70c2a7f6 100644
--- a/ssh-agent.c
+++ b/ssh-agent.c
@@ -1,22 +1,15 @@
-/*	$OpenBSD: ssh-agent.c,v 1.20 1999/11/19 10:20:51 markus Exp $	*/
+/*	$OpenBSD: ssh-agent.c,v 1.22 1999/11/24 00:26:03 deraadt Exp $	*/
 
 /*
-
-ssh-agent.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 03:46:59 1995 ylo
-
-The authentication agent program.
-
-*/
+ * 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 03:46:59 1995 ylo
+ * The authentication agent program.
+ */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh-agent.c,v 1.20 1999/11/19 10:20:51 markus Exp $");
+RCSID("$OpenBSD: ssh-agent.c,v 1.22 1999/11/24 00:26:03 deraadt Exp $");
 
 #include "ssh.h"
 #include "rsa.h"
@@ -35,27 +28,21 @@ RCSID("$OpenBSD: ssh-agent.c,v 1.20 1999/11/19 10:20:51 markus Exp $");
 #include <ssl/md5.h>
 #endif
 
-#ifdef HAVE___PROGNAME
-extern char *__progname;
-#else /* HAVE___PROGNAME */
-const char *__progname = "ssh-agent";
-#endif /* HAVE___PROGNAME */
-
-typedef struct
-{
-  int fd;
-  enum { AUTH_UNUSED, AUTH_SOCKET, AUTH_CONNECTION } type;
-  Buffer input;
-  Buffer output;
+typedef struct {
+	int fd;
+	enum {
+		AUTH_UNUSED, AUTH_SOCKET, AUTH_CONNECTION
+	} type;
+	Buffer input;
+	Buffer output;
 } SocketEntry;
 
 unsigned int sockets_alloc = 0;
 SocketEntry *sockets = NULL;
 
-typedef struct
-{
-  RSA *key;
-  char *comment;
+typedef struct {
+	RSA *key;
+	char *comment;
 } Identity;
 
 unsigned int num_identities = 0;
@@ -70,640 +57,601 @@ int parent_pid = -1;
 char socket_name[1024];
 char socket_dir[1024];
 
+#ifdef HAVE___PROGNAME
+extern char *__progname;
+#else /* HAVE___PROGNAME */
+const char *__progname = "ssh-agent";
+#endif /* HAVE___PROGNAME */
+
 void
 process_request_identity(SocketEntry *e)
 {
-  Buffer msg;
-  int i;
-
-  buffer_init(&msg);
-  buffer_put_char(&msg, SSH_AGENT_RSA_IDENTITIES_ANSWER);
-  buffer_put_int(&msg, num_identities);
-  for (i = 0; i < num_identities; i++)
-    {
-      buffer_put_int(&msg, BN_num_bits(identities[i].key->n));
-      buffer_put_bignum(&msg, identities[i].key->e);
-      buffer_put_bignum(&msg, identities[i].key->n);
-      buffer_put_string(&msg, identities[i].comment, 
-			strlen(identities[i].comment));
-    }
-  buffer_put_int(&e->output, buffer_len(&msg));
-  buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
-  buffer_free(&msg);
+	Buffer msg;
+	int i;
+
+	buffer_init(&msg);
+	buffer_put_char(&msg, SSH_AGENT_RSA_IDENTITIES_ANSWER);
+	buffer_put_int(&msg, num_identities);
+	for (i = 0; i < num_identities; i++) {
+		buffer_put_int(&msg, BN_num_bits(identities[i].key->n));
+		buffer_put_bignum(&msg, identities[i].key->e);
+		buffer_put_bignum(&msg, identities[i].key->n);
+		buffer_put_string(&msg, identities[i].comment,
+				  strlen(identities[i].comment));
+	}
+	buffer_put_int(&e->output, buffer_len(&msg));
+	buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
+	buffer_free(&msg);
 }
 
 void
 process_authentication_challenge(SocketEntry *e)
 {
-  int i, pub_bits, len;
-  BIGNUM *pub_e, *pub_n, *challenge;
-  Buffer msg;
-  MD5_CTX md;
-  unsigned char buf[32], mdbuf[16], session_id[16];
-  unsigned int response_type;
-
-  buffer_init(&msg);
-  pub_e = BN_new();
-  pub_n = BN_new();
-  challenge = BN_new();
-  pub_bits = buffer_get_int(&e->input);
-  buffer_get_bignum(&e->input, pub_e);
-  buffer_get_bignum(&e->input, pub_n);
-  buffer_get_bignum(&e->input, challenge);
-  if (buffer_len(&e->input) == 0)
-    {
-      /* Compatibility code for old servers. */
-      memset(session_id, 0, 16);
-      response_type = 0;
-    }
-  else
-    {
-      /* New code. */
-      buffer_get(&e->input, (char *)session_id, 16);
-      response_type = buffer_get_int(&e->input);
-    }
-  for (i = 0; i < num_identities; i++)
-    if (pub_bits == BN_num_bits(identities[i].key->n) &&
-	BN_cmp(pub_e, identities[i].key->e) == 0 &&
-	BN_cmp(pub_n, identities[i].key->n) == 0)
-      {
-	/* Decrypt the challenge using the private key. */
-	rsa_private_decrypt(challenge, challenge, identities[i].key);
-
-	/* Compute the desired response. */
-	switch (response_type)
-	  {
-	  case 0: /* As of protocol 1.0 */
-	    /* This response type is no longer supported. */
-	    log("Compatibility with ssh protocol 1.0 no longer supported.");
-	    buffer_put_char(&msg, SSH_AGENT_FAILURE);
-	    goto send;
-
-	  case 1: /* As of protocol 1.1 */
-	    /* The response is MD5 of decrypted challenge plus session id. */
-	    len = BN_num_bytes(challenge);
-
-	    if (len <= 0 || len > 32) {
-	      fatal("process_authentication_challenge: "
-		    "bad challenge length %d", len);
-	    }
-
-	    memset(buf, 0, 32);
-	    BN_bn2bin(challenge, buf + 32 - len);
-	    MD5_Init(&md);
-	    MD5_Update(&md, buf, 32);
-	    MD5_Update(&md, session_id, 16);
-	    MD5_Final(mdbuf, &md);
-	    break;
-
-	  default:
-	    fatal("process_authentication_challenge: bad response_type %d", 
-		  response_type);
-	    break;
-	  }
-
-	/* Send the response. */
-	buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
-	for (i = 0; i < 16; i++)
-	  buffer_put_char(&msg, mdbuf[i]);
-
-	goto send;
-      }
-  /* Unknown identity.  Send failure. */
-  buffer_put_char(&msg, SSH_AGENT_FAILURE);
- send:
-  buffer_put_int(&e->output, buffer_len(&msg));
-  buffer_append(&e->output, buffer_ptr(&msg),
-		buffer_len(&msg));
-  buffer_free(&msg);
-  BN_clear_free(pub_e);
-  BN_clear_free(pub_n);
-  BN_clear_free(challenge);
+	int i, pub_bits, len;
+	BIGNUM *pub_e, *pub_n, *challenge;
+	Buffer msg;
+	MD5_CTX md;
+	unsigned char buf[32], mdbuf[16], session_id[16];
+	unsigned int response_type;
+
+	buffer_init(&msg);
+	pub_e = BN_new();
+	pub_n = BN_new();
+	challenge = BN_new();
+	pub_bits = buffer_get_int(&e->input);
+	buffer_get_bignum(&e->input, pub_e);
+	buffer_get_bignum(&e->input, pub_n);
+	buffer_get_bignum(&e->input, challenge);
+	if (buffer_len(&e->input) == 0) {
+		/* Compatibility code for old servers. */
+		memset(session_id, 0, 16);
+		response_type = 0;
+	} else {
+		/* New code. */
+		buffer_get(&e->input, (char *) session_id, 16);
+		response_type = buffer_get_int(&e->input);
+	}
+	for (i = 0; i < num_identities; i++)
+		if (pub_bits == BN_num_bits(identities[i].key->n) &&
+		    BN_cmp(pub_e, identities[i].key->e) == 0 &&
+		    BN_cmp(pub_n, identities[i].key->n) == 0) {
+			/* Decrypt the challenge using the private key. */
+			rsa_private_decrypt(challenge, challenge, identities[i].key);
+
+			/* Compute the desired response. */
+			switch (response_type) {
+			case 0:/* As of protocol 1.0 */
+				/* This response type is no longer supported. */
+				log("Compatibility with ssh protocol 1.0 no longer supported.");
+				buffer_put_char(&msg, SSH_AGENT_FAILURE);
+				goto send;
+
+			case 1:/* As of protocol 1.1 */
+				/* The response is MD5 of decrypted challenge plus session id. */
+				len = BN_num_bytes(challenge);
+
+				if (len <= 0 || len > 32) {
+					fatal("process_authentication_challenge: "
+					 "bad challenge length %d", len);
+				}
+				memset(buf, 0, 32);
+				BN_bn2bin(challenge, buf + 32 - len);
+				MD5_Init(&md);
+				MD5_Update(&md, buf, 32);
+				MD5_Update(&md, session_id, 16);
+				MD5_Final(mdbuf, &md);
+				break;
+
+			default:
+				fatal("process_authentication_challenge: bad response_type %d",
+				      response_type);
+				break;
+			}
+
+			/* Send the response. */
+			buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
+			for (i = 0; i < 16; i++)
+				buffer_put_char(&msg, mdbuf[i]);
+
+			goto send;
+		}
+	/* Unknown identity.  Send failure. */
+	buffer_put_char(&msg, SSH_AGENT_FAILURE);
+send:
+	buffer_put_int(&e->output, buffer_len(&msg));
+	buffer_append(&e->output, buffer_ptr(&msg),
+		      buffer_len(&msg));
+	buffer_free(&msg);
+	BN_clear_free(pub_e);
+	BN_clear_free(pub_n);
+	BN_clear_free(challenge);
 }
 
 void
 process_remove_identity(SocketEntry *e)
 {
-  unsigned int bits;
-  unsigned int i;
-  BIGNUM *dummy, *n;
-  
-  dummy = BN_new();
-  n = BN_new();
-  
-  /* Get the key from the packet. */
-  bits = buffer_get_int(&e->input);
-  buffer_get_bignum(&e->input, dummy);
-  buffer_get_bignum(&e->input, n);
-
-  if (bits != BN_num_bits(n))
-    error("Warning: keysize mismatch: actual %d, announced %d",
-	  BN_num_bits(n), bits);
-  
-  /* Check if we have the key. */
-  for (i = 0; i < num_identities; i++)
-    if (BN_cmp(identities[i].key->n, n) == 0)
-      {
-	/* We have this key.  Free the old key.  Since we don\'t want to leave
-	   empty slots in the middle of the array, we actually free the
-	   key there and copy data from the last entry. */
-	RSA_free(identities[i].key);
-	xfree(identities[i].comment);
-	if (i < num_identities - 1)
-	  identities[i] = identities[num_identities - 1];
-	num_identities--;
-	BN_clear_free(dummy);
-	BN_clear_free(n);
-
-	/* Send success. */
+	unsigned int bits;
+	unsigned int i;
+	BIGNUM *dummy, *n;
+
+	dummy = BN_new();
+	n = BN_new();
+
+	/* Get the key from the packet. */
+	bits = buffer_get_int(&e->input);
+	buffer_get_bignum(&e->input, dummy);
+	buffer_get_bignum(&e->input, n);
+
+	if (bits != BN_num_bits(n))
+		error("Warning: keysize mismatch: actual %d, announced %d",
+		      BN_num_bits(n), bits);
+
+	/* Check if we have the key. */
+	for (i = 0; i < num_identities; i++)
+		if (BN_cmp(identities[i].key->n, n) == 0) {
+			/* We have this key.  Free the old key.  Since we
+			   don\'t want to leave empty slots in the middle
+			   of the array, we actually free the key there
+			   and copy data from the last entry. */
+			RSA_free(identities[i].key);
+			xfree(identities[i].comment);
+			if (i < num_identities - 1)
+				identities[i] = identities[num_identities - 1];
+			num_identities--;
+			BN_clear_free(dummy);
+			BN_clear_free(n);
+
+			/* Send success. */
+			buffer_put_int(&e->output, 1);
+			buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
+			return;
+		}
+	/* We did not have the key. */
+	BN_clear(dummy);
+	BN_clear(n);
+
+	/* Send failure. */
 	buffer_put_int(&e->output, 1);
-	buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
-	return;
-      }
-  /* We did not have the key. */
-  BN_clear(dummy);
-  BN_clear(n);
-
-  /* Send failure. */
-  buffer_put_int(&e->output, 1);
-  buffer_put_char(&e->output, SSH_AGENT_FAILURE);
+	buffer_put_char(&e->output, SSH_AGENT_FAILURE);
 }
 
-/* Removes all identities from the agent. */
-
+/*
+ * Removes all identities from the agent.
+ */
 void
 process_remove_all_identities(SocketEntry *e)
 {
-  unsigned int i;
-  
-  /* Loop over all identities and clear the keys. */
-  for (i = 0; i < num_identities; i++)
-    {
-      RSA_free(identities[i].key);
-      xfree(identities[i].comment);
-    }
-
-  /* Mark that there are no identities. */
-  num_identities = 0;
-
-  /* Send success. */
-  buffer_put_int(&e->output, 1);
-  buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
-  return;
-}
+	unsigned int i;
 
-/* Adds an identity to the agent. */
+	/* Loop over all identities and clear the keys. */
+	for (i = 0; i < num_identities; i++) {
+		RSA_free(identities[i].key);
+		xfree(identities[i].comment);
+	}
 
-void
-process_add_identity(SocketEntry *e)
-{
-  RSA *k;
-  int i;
-  BIGNUM *aux;
-  BN_CTX *ctx;
-  
-  if (num_identities == 0)
-    identities = xmalloc(sizeof(Identity));
-  else
-    identities = xrealloc(identities, (num_identities + 1) * sizeof(Identity));
-
-  identities[num_identities].key = RSA_new();
-  k = identities[num_identities].key;
-  buffer_get_int(&e->input); /* bits */
-  k->n = BN_new();
-  buffer_get_bignum(&e->input, k->n);
-  k->e = BN_new();
-  buffer_get_bignum(&e->input, k->e);
-  k->d = BN_new();
-  buffer_get_bignum(&e->input, k->d);
-  k->iqmp = BN_new();
-  buffer_get_bignum(&e->input, k->iqmp);
-  /* SSH and SSL have p and q swapped */
-  k->q = BN_new();
-  buffer_get_bignum(&e->input, k->q); /* p */
-  k->p = BN_new();
-  buffer_get_bignum(&e->input, k->p); /* q */
-
-  /* Generate additional parameters */
-  aux = BN_new();
-  ctx = BN_CTX_new();
-
-  BN_sub(aux, k->q, BN_value_one());
-  k->dmq1 = BN_new();
-  BN_mod(k->dmq1, k->d, aux, ctx);
-
-  BN_sub(aux, k->p, BN_value_one());
-  k->dmp1 = BN_new();
-  BN_mod(k->dmp1, k->d, aux, ctx);
-
-  BN_clear_free(aux);
-  BN_CTX_free(ctx);
-  
-  identities[num_identities].comment = buffer_get_string(&e->input, NULL);
-
-  /* Check if we already have the key. */
-  for (i = 0; i < num_identities; i++)
-    if (BN_cmp(identities[i].key->n, k->n) == 0)
-      {
-	/* We already have this key.  Clear and free the new data and
-	   return success. */
-	RSA_free(k);
-	xfree(identities[num_identities].comment);
+	/* Mark that there are no identities. */
+	num_identities = 0;
 
 	/* Send success. */
 	buffer_put_int(&e->output, 1);
 	buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
 	return;
-      }
-
-  /* Increment the number of identities. */
-  num_identities++;
-  
-  /* Send a success message. */
-  buffer_put_int(&e->output, 1);
-  buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
+}
+
+/*
+ * Adds an identity to the agent.
+ */
+void
+process_add_identity(SocketEntry *e)
+{
+	RSA *k;
+	int i;
+	BIGNUM *aux;
+	BN_CTX *ctx;
+
+	if (num_identities == 0)
+		identities = xmalloc(sizeof(Identity));
+	else
+		identities = xrealloc(identities, (num_identities + 1) * sizeof(Identity));
+
+	identities[num_identities].key = RSA_new();
+	k = identities[num_identities].key;
+	buffer_get_int(&e->input);	/* bits */
+	k->n = BN_new();
+	buffer_get_bignum(&e->input, k->n);
+	k->e = BN_new();
+	buffer_get_bignum(&e->input, k->e);
+	k->d = BN_new();
+	buffer_get_bignum(&e->input, k->d);
+	k->iqmp = BN_new();
+	buffer_get_bignum(&e->input, k->iqmp);
+	/* SSH and SSL have p and q swapped */
+	k->q = BN_new();
+	buffer_get_bignum(&e->input, k->q);	/* p */
+	k->p = BN_new();
+	buffer_get_bignum(&e->input, k->p);	/* q */
+
+	/* Generate additional parameters */
+	aux = BN_new();
+	ctx = BN_CTX_new();
+
+	BN_sub(aux, k->q, BN_value_one());
+	k->dmq1 = BN_new();
+	BN_mod(k->dmq1, k->d, aux, ctx);
+
+	BN_sub(aux, k->p, BN_value_one());
+	k->dmp1 = BN_new();
+	BN_mod(k->dmp1, k->d, aux, ctx);
+
+	BN_clear_free(aux);
+	BN_CTX_free(ctx);
+
+	identities[num_identities].comment = buffer_get_string(&e->input, NULL);
+
+	/* Check if we already have the key. */
+	for (i = 0; i < num_identities; i++)
+		if (BN_cmp(identities[i].key->n, k->n) == 0) {
+			/* We already have this key.  Clear and free the
+			   new data and return success. */
+			RSA_free(k);
+			xfree(identities[num_identities].comment);
+
+			/* Send success. */
+			buffer_put_int(&e->output, 1);
+			buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
+			return;
+		}
+	/* Increment the number of identities. */
+	num_identities++;
+
+	/* Send a success message. */
+	buffer_put_int(&e->output, 1);
+	buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
 }
 
 void
 process_message(SocketEntry *e)
 {
-  unsigned int msg_len;
-  unsigned int type;
-  unsigned char *cp;
-  if (buffer_len(&e->input) < 5)
-    return; /* Incomplete message. */
-  cp = (unsigned char *)buffer_ptr(&e->input);
-  msg_len = GET_32BIT(cp);
-  if (msg_len > 256 * 1024)
-    {
-      shutdown(e->fd, SHUT_RDWR);
-      close(e->fd);
-      e->type = AUTH_UNUSED;
-      return;
-    }
-  if (buffer_len(&e->input) < msg_len + 4)
-    return;
-  buffer_consume(&e->input, 4);
-  type = buffer_get_char(&e->input);
-
-  switch (type)
-    {
-    case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
-      process_request_identity(e);
-      break;
-    case SSH_AGENTC_RSA_CHALLENGE:
-      process_authentication_challenge(e);
-      break;
-    case SSH_AGENTC_ADD_RSA_IDENTITY:
-      process_add_identity(e);
-      break;
-    case SSH_AGENTC_REMOVE_RSA_IDENTITY:
-      process_remove_identity(e);
-      break;
-    case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
-      process_remove_all_identities(e);
-      break;
-    default:
-      /* Unknown message.  Respond with failure. */
-      error("Unknown message %d", type);
-      buffer_clear(&e->input);
-      buffer_put_int(&e->output, 1);
-      buffer_put_char(&e->output, SSH_AGENT_FAILURE);
-      break;
-    }
+	unsigned int msg_len;
+	unsigned int type;
+	unsigned char *cp;
+	if (buffer_len(&e->input) < 5)
+		return;		/* Incomplete message. */
+	cp = (unsigned char *) buffer_ptr(&e->input);
+	msg_len = GET_32BIT(cp);
+	if (msg_len > 256 * 1024) {
+		shutdown(e->fd, SHUT_RDWR);
+		close(e->fd);
+		e->type = AUTH_UNUSED;
+		return;
+	}
+	if (buffer_len(&e->input) < msg_len + 4)
+		return;
+	buffer_consume(&e->input, 4);
+	type = buffer_get_char(&e->input);
+
+	switch (type) {
+	case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
+		process_request_identity(e);
+		break;
+	case SSH_AGENTC_RSA_CHALLENGE:
+		process_authentication_challenge(e);
+		break;
+	case SSH_AGENTC_ADD_RSA_IDENTITY:
+		process_add_identity(e);
+		break;
+	case SSH_AGENTC_REMOVE_RSA_IDENTITY:
+		process_remove_identity(e);
+		break;
+	case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
+		process_remove_all_identities(e);
+		break;
+	default:
+		/* Unknown message.  Respond with failure. */
+		error("Unknown message %d", type);
+		buffer_clear(&e->input);
+		buffer_put_int(&e->output, 1);
+		buffer_put_char(&e->output, SSH_AGENT_FAILURE);
+		break;
+	}
 }
 
 void
 new_socket(int type, int fd)
 {
-  unsigned int i, old_alloc;
-  if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
-    error("fcntl O_NONBLOCK: %s", strerror(errno));
-
-  if (fd > max_fd)
-    max_fd = fd;
-
-  for (i = 0; i < sockets_alloc; i++)
-    if (sockets[i].type == AUTH_UNUSED)
-      {
-	sockets[i].fd = fd;
-	sockets[i].type = type;
-	buffer_init(&sockets[i].input);
-	buffer_init(&sockets[i].output);
-	return;
-      }
-  old_alloc = sockets_alloc;
-  sockets_alloc += 10;
-  if (sockets)
-    sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
-  else
-    sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
-  for (i = old_alloc; i < sockets_alloc; i++)
-    sockets[i].type = AUTH_UNUSED;
-  sockets[old_alloc].type = type;
-  sockets[old_alloc].fd = fd;
-  buffer_init(&sockets[old_alloc].input);
-  buffer_init(&sockets[old_alloc].output);
+	unsigned int i, old_alloc;
+	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
+		error("fcntl O_NONBLOCK: %s", strerror(errno));
+
+	if (fd > max_fd)
+		max_fd = fd;
+
+	for (i = 0; i < sockets_alloc; i++)
+		if (sockets[i].type == AUTH_UNUSED) {
+			sockets[i].fd = fd;
+			sockets[i].type = type;
+			buffer_init(&sockets[i].input);
+			buffer_init(&sockets[i].output);
+			return;
+		}
+	old_alloc = sockets_alloc;
+	sockets_alloc += 10;
+	if (sockets)
+		sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
+	else
+		sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
+	for (i = old_alloc; i < sockets_alloc; i++)
+		sockets[i].type = AUTH_UNUSED;
+	sockets[old_alloc].type = type;
+	sockets[old_alloc].fd = fd;
+	buffer_init(&sockets[old_alloc].input);
+	buffer_init(&sockets[old_alloc].output);
 }
 
 void
 prepare_select(fd_set *readset, fd_set *writeset)
 {
-  unsigned int i;
-  for (i = 0; i < sockets_alloc; i++)
-    switch (sockets[i].type)
-      {
-      case AUTH_SOCKET:
-      case AUTH_CONNECTION:
-	FD_SET(sockets[i].fd, readset);
-	if (buffer_len(&sockets[i].output) > 0)
-	  FD_SET(sockets[i].fd, writeset);
-	break;
-      case AUTH_UNUSED:
-	break;
-      default:
-	fatal("Unknown socket type %d", sockets[i].type);
-	break;
-      }
+	unsigned int i;
+	for (i = 0; i < sockets_alloc; i++)
+		switch (sockets[i].type) {
+		case AUTH_SOCKET:
+		case AUTH_CONNECTION:
+			FD_SET(sockets[i].fd, readset);
+			if (buffer_len(&sockets[i].output) > 0)
+				FD_SET(sockets[i].fd, writeset);
+			break;
+		case AUTH_UNUSED:
+			break;
+		default:
+			fatal("Unknown socket type %d", sockets[i].type);
+			break;
+		}
 }
 
-void after_select(fd_set *readset, fd_set *writeset)
+void 
+after_select(fd_set *readset, fd_set *writeset)
 {
-  unsigned int i;
-  int len, sock;
-  char buf[1024];
-  struct sockaddr_un sunaddr;
-
-  for (i = 0; i < sockets_alloc; i++)
-    switch (sockets[i].type)
-      {
-      case AUTH_UNUSED:
-	break;
-      case AUTH_SOCKET:
-	if (FD_ISSET(sockets[i].fd, readset))
-	  {
-	    len = sizeof(sunaddr);
-	    sock = accept(sockets[i].fd, (struct sockaddr *)&sunaddr, &len);
-	    if (sock < 0)
-	      {
-		perror("accept from AUTH_SOCKET");
-		break;
-	      }
-	    new_socket(AUTH_CONNECTION, sock);
-	  }
-	break;
-      case AUTH_CONNECTION:
-	if (buffer_len(&sockets[i].output) > 0 &&
-	    FD_ISSET(sockets[i].fd, writeset))
-	  {
-	    len = write(sockets[i].fd, buffer_ptr(&sockets[i].output),
-			buffer_len(&sockets[i].output));
-	    if (len <= 0)
-	      {
-		shutdown(sockets[i].fd, SHUT_RDWR);
-		close(sockets[i].fd);
-		sockets[i].type = AUTH_UNUSED;
-		break;
-	      }
-	    buffer_consume(&sockets[i].output, len);
-	  }
-	if (FD_ISSET(sockets[i].fd, readset))
-	  {
-	    len = read(sockets[i].fd, buf, sizeof(buf));
-	    if (len <= 0)
-	      {
-		shutdown(sockets[i].fd, SHUT_RDWR);
-		close(sockets[i].fd);
-		sockets[i].type = AUTH_UNUSED;
-		break;
-	      }
-	    buffer_append(&sockets[i].input, buf, len);
-	    process_message(&sockets[i]);
-	  }
-	break;
-      default:
-	fatal("Unknown type %d", sockets[i].type);
-      }
+	unsigned int i;
+	int len, sock;
+	char buf[1024];
+	struct sockaddr_un sunaddr;
+
+	for (i = 0; i < sockets_alloc; i++)
+		switch (sockets[i].type) {
+		case AUTH_UNUSED:
+			break;
+		case AUTH_SOCKET:
+			if (FD_ISSET(sockets[i].fd, readset)) {
+				len = sizeof(sunaddr);
+				sock = accept(sockets[i].fd, (struct sockaddr *) & sunaddr, &len);
+				if (sock < 0) {
+					perror("accept from AUTH_SOCKET");
+					break;
+				}
+				new_socket(AUTH_CONNECTION, sock);
+			}
+			break;
+		case AUTH_CONNECTION:
+			if (buffer_len(&sockets[i].output) > 0 &&
+			    FD_ISSET(sockets[i].fd, writeset)) {
+				len = write(sockets[i].fd, buffer_ptr(&sockets[i].output),
+					 buffer_len(&sockets[i].output));
+				if (len <= 0) {
+					shutdown(sockets[i].fd, SHUT_RDWR);
+					close(sockets[i].fd);
+					sockets[i].type = AUTH_UNUSED;
+					break;
+				}
+				buffer_consume(&sockets[i].output, len);
+			}
+			if (FD_ISSET(sockets[i].fd, readset)) {
+				len = read(sockets[i].fd, buf, sizeof(buf));
+				if (len <= 0) {
+					shutdown(sockets[i].fd, SHUT_RDWR);
+					close(sockets[i].fd);
+					sockets[i].type = AUTH_UNUSED;
+					break;
+				}
+				buffer_append(&sockets[i].input, buf, len);
+				process_message(&sockets[i]);
+			}
+			break;
+		default:
+			fatal("Unknown type %d", sockets[i].type);
+		}
 }
 
 void
 check_parent_exists(int sig)
 {
-  if (kill(parent_pid, 0) < 0)
-    {
-      /* printf("Parent has died - Authentication agent exiting.\n"); */
-      exit(1);
-    }
-  signal(SIGALRM, check_parent_exists);
-  alarm(10);
+	if (kill(parent_pid, 0) < 0) {
+		/* printf("Parent has died - Authentication agent exiting.\n"); */
+		exit(1);
+	}
+	signal(SIGALRM, check_parent_exists);
+	alarm(10);
 }
 
 void
 cleanup_socket(void)
 {
-  remove(socket_name);
-  rmdir(socket_dir);
+	remove(socket_name);
+	rmdir(socket_dir);
 }
 
 void
 cleanup_exit(int i)
 {
-  cleanup_socket();
-  exit(i);
+	cleanup_socket();
+	exit(i);
 }
 
 void
 usage()
 {
-  fprintf(stderr, "ssh-agent version %s\n", SSH_VERSION);
-  fprintf(stderr, "Usage: %s [-c | -s] [-k] [command {args...]]\n",
-	  __progname);
-  exit(1);
+	fprintf(stderr, "ssh-agent version %s\n", SSH_VERSION);
+	fprintf(stderr, "Usage: %s [-c | -s] [-k] [command {args...]]\n",
+		__progname);
+	exit(1);
 }
 
 int
 main(int ac, char **av)
 {
-  fd_set readset, writeset;
-  int sock, c_flag = 0, k_flag = 0, s_flag = 0, ch;
-  struct sockaddr_un sunaddr;
-  pid_t pid;
-  char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
-
-  /* check if RSA support exists */
-  if (rsa_alive() == 0) {
-    fprintf(stderr,
-      "%s: no RSA support in libssl and libcrypto.  See ssl(8).\n",
-      __progname);
-    exit(1);
-  }
-
+	fd_set readset, writeset;
+	int sock, c_flag = 0, k_flag = 0, s_flag = 0, ch;
+	struct sockaddr_un sunaddr;
+	pid_t pid;
+	char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
+
+	/* check if RSA support exists */
+	if (rsa_alive() == 0) {
+		fprintf(stderr,
+			"%s: no RSA support in libssl and libcrypto.  See ssl(8).\n",
+			__progname);
+		exit(1);
+	}
 #if defined(__GNU_LIBRARY__)
-  while ((ch = getopt(ac, av, "+cks")) != -1)
+	while ((ch = getopt(ac, av, "+cks")) != -1) {
 #else 
-  while ((ch = getopt(ac, av, "cks")) != -1)
+	while ((ch = getopt(ac, av, "cks")) != -1) {
 #endif /* defined(__GNU_LIBRARY__) */
-    {
-      switch (ch)
-	{
-	case 'c':
-	  if (s_flag)
-	    usage();
-	  c_flag++;
-	  break;
-	case 'k':
-	  k_flag++;
-	  break;
-	case 's':
-	  if (c_flag)
-	    usage();
-	  s_flag++;
-	  break;
-	default:
-	  usage();
+		switch (ch) {
+		case 'c':
+			if (s_flag)
+				usage();
+			c_flag++;
+			break;
+		case 'k':
+			k_flag++;
+			break;
+		case 's':
+			if (c_flag)
+				usage();
+			s_flag++;
+			break;
+		default:
+			usage();
+		}
 	}
-    }
-  ac -= optind;
-  av += optind;
-
-  if (ac > 0 && (c_flag || k_flag || s_flag))
-    usage();
-
-  if (ac == 0 && !c_flag && !k_flag && !s_flag)
-    {
-      shell = getenv("SHELL");
-      if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
-	c_flag = 1;
-    }
-
-  if (k_flag)
-    {
-      pidstr = getenv(SSH_AGENTPID_ENV_NAME);
-      if (pidstr == NULL)
-	{
-	  fprintf(stderr, "%s not set, cannot kill agent\n",
-		  SSH_AGENTPID_ENV_NAME);
-	  exit(1);
+	ac -= optind;
+	av += optind;
+
+	if (ac > 0 && (c_flag || k_flag || s_flag))
+		usage();
+
+	if (ac == 0 && !c_flag && !k_flag && !s_flag) {
+		shell = getenv("SHELL");
+		if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
+			c_flag = 1;
 	}
-      pid = atoi(pidstr);
-      if (pid < 1)		/* XXX PID_MAX check too */
-	{
-	  fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
-		  SSH_AGENTPID_ENV_NAME, pidstr);
-	  exit(1);
+	if (k_flag) {
+		pidstr = getenv(SSH_AGENTPID_ENV_NAME);
+		if (pidstr == NULL) {
+			fprintf(stderr, "%s not set, cannot kill agent\n",
+				SSH_AGENTPID_ENV_NAME);
+			exit(1);
+		}
+		pid = atoi(pidstr);
+		if (pid < 1) {	/* XXX PID_MAX check too */
+			fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
+				SSH_AGENTPID_ENV_NAME, pidstr);
+			exit(1);
+		}
+		if (kill(pid, SIGTERM) == -1) {
+			perror("kill");
+			exit(1);
+		}
+		format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
+		printf(format, SSH_AUTHSOCKET_ENV_NAME);
+		printf(format, SSH_AGENTPID_ENV_NAME);
+		printf("echo Agent pid %d killed;\n", pid);
+		exit(0);
 	}
-      if (kill(pid, SIGTERM) == -1)
-	{
-	  perror("kill");
-	  exit(1);
+	parent_pid = getpid();
+
+	/* Create private directory for agent socket */
+	strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
+	if (mkdtemp(socket_dir) == NULL) {
+		perror("mkdtemp: private socket dir");
+		exit(1);
+	}
+	snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir,
+		 parent_pid);
+
+	/* Create socket early so it will exist before command gets run
+	   from the parent.  */
+	sock = socket(AF_UNIX, SOCK_STREAM, 0);
+	if (sock < 0) {
+		perror("socket");
+		cleanup_exit(1);
+	}
+	memset(&sunaddr, 0, sizeof(sunaddr));
+	sunaddr.sun_family = AF_UNIX;
+	strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
+	if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
+		perror("bind");
+		cleanup_exit(1);
+	}
+	if (listen(sock, 5) < 0) {
+		perror("listen");
+		cleanup_exit(1);
 	}
-      format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
-      printf(format, SSH_AUTHSOCKET_ENV_NAME);
-      printf(format, SSH_AGENTPID_ENV_NAME);
-      printf("echo Agent pid %d killed;\n", pid);
-      exit(0);
-    }
-
-  parent_pid = getpid();
-
-  /* Create private directory for agent socket */
-  strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
-  if (mkdtemp(socket_dir) == NULL) {
-      perror("mkdtemp: private socket dir");
-      exit(1);
-  }
-  snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir,
-	   parent_pid);
-
-  /* Create socket early so it will exist before command gets run from
-     the parent.  */
-  sock = socket(AF_UNIX, SOCK_STREAM, 0);
-  if (sock < 0)
-    {
-      perror("socket");
-      cleanup_exit(1);
-    }
-  memset(&sunaddr, 0, sizeof(sunaddr));
-  sunaddr.sun_family = AF_UNIX;
-  strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
-  if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0)
-    {
-      perror("bind");
-      cleanup_exit(1);
-    }
-  if (listen(sock, 5) < 0)
-    {
-      perror("listen");
-      cleanup_exit(1);
-    }
-
-  /* Fork, and have the parent execute the command, if any, or present the
-     socket data.  The child continues as the authentication agent. */
-  pid = fork();
-  if (pid == -1)
-    {
-      perror("fork");
-      exit(1);
-    }
-  if (pid != 0)
-    { /* Parent - execute the given command. */
-      close(sock);
-      snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid);
-      if (ac == 0)
-	{
-	  format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";