Revert part of 180714 - the intent was to flatten dist, not to nuke it.

1 files changed, 679 insertions, 0 deletions

diff --git a/crypto/openssh/authfile.c b/crypto/openssh/authfile.c
new file mode 100644
index 0000000..735c647
--- /dev/null
+++ b/crypto/openssh/authfile.c
@@ -0,0 +1,679 @@
+/* $OpenBSD: authfile.c,v 1.76 2006/08/03 03:34:41 deraadt Exp $ */
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * This file contains functions for reading and writing identity files, and
+ * for reading the passphrase from the user.
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose.  Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ *
+ *
+ * Copyright (c) 2000 Markus Friedl.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/param.h>
+#include <sys/uio.h>
+
+#include <openssl/err.h>
+#include <openssl/evp.h>
+#include <openssl/pem.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "xmalloc.h"
+#include "cipher.h"
+#include "buffer.h"
+#include "key.h"
+#include "ssh.h"
+#include "log.h"
+#include "authfile.h"
+#include "rsa.h"
+#include "misc.h"
+#include "atomicio.h"
+
+/* Version identification string for SSH v1 identity files. */
+static const char authfile_id_string[] =
+    "SSH PRIVATE KEY FILE FORMAT 1.1\n";
+
+/*
+ * Saves the authentication (private) key in a file, encrypting it with
+ * passphrase.  The identification of the file (lowest 64 bits of n) will
+ * precede the key to provide identification of the key without needing a
+ * passphrase.
+ */
+
+static int
+key_save_private_rsa1(Key *key, const char *filename, const char *passphrase,
+    const char *comment)
+{
+	Buffer buffer, encrypted;
+	u_char buf[100], *cp;
+	int fd, i, cipher_num;
+	CipherContext ciphercontext;
+	Cipher *cipher;
+	u_int32_t rnd;
+
+	/*
+	 * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting
+	 * to another cipher; otherwise use SSH_AUTHFILE_CIPHER.
+	 */
+	cipher_num = (strcmp(passphrase, "") == 0) ?
+	    SSH_CIPHER_NONE : SSH_AUTHFILE_CIPHER;
+	if ((cipher = cipher_by_number(cipher_num)) == NULL)
+		fatal("save_private_key_rsa: bad cipher");
+
+	/* This buffer is used to built the secret part of the private key. */
+	buffer_init(&buffer);
+
+	/* Put checkbytes for checking passphrase validity. */
+	rnd = arc4random();
+	buf[0] = rnd & 0xff;
+	buf[1] = (rnd >> 8) & 0xff;
+	buf[2] = buf[0];
+	buf[3] = buf[1];
+	buffer_append(&buffer, buf, 4);
+
+	/*
+	 * Store the private key (n and e will not be stored because they
+	 * will be stored in plain text, and storing them also in encrypted
+	 * format would just give known plaintext).
+	 */
+	buffer_put_bignum(&buffer, key->rsa->d);
+	buffer_put_bignum(&buffer, key->rsa->iqmp);
+	buffer_put_bignum(&buffer, key->rsa->q);	/* reverse from SSL p */
+	buffer_put_bignum(&buffer, key->rsa->p);	/* reverse from SSL q */
+
+	/* Pad the part to be encrypted until its size is a multiple of 8. */
+	while (buffer_len(&buffer) % 8 != 0)
+		buffer_put_char(&buffer, 0);
+
+	/* This buffer will be used to contain the data in the file. */
+	buffer_init(&encrypted);
+
+	/* First store keyfile id string. */
+	for (i = 0; authfile_id_string[i]; i++)
+		buffer_put_char(&encrypted, authfile_id_string[i]);
+	buffer_put_char(&encrypted, 0);
+
+	/* Store cipher type. */
+	buffer_put_char(&encrypted, cipher_num);
+	buffer_put_int(&encrypted, 0);	/* For future extension */
+
+	/* Store public key.  This will be in plain text. */
+	buffer_put_int(&encrypted, BN_num_bits(key->rsa->n));
+	buffer_put_bignum(&encrypted, key->rsa->n);
+	buffer_put_bignum(&encrypted, key->rsa->e);
+	buffer_put_cstring(&encrypted, comment);
+
+	/* Allocate space for the private part of the key in the buffer. */
+	cp = buffer_append_space(&encrypted, buffer_len(&buffer));
+
+	cipher_set_key_string(&ciphercontext, cipher, passphrase,
+	    CIPHER_ENCRYPT);
+	cipher_crypt(&ciphercontext, cp,
+	    buffer_ptr(&buffer), buffer_len(&buffer));
+	cipher_cleanup(&ciphercontext);
+	memset(&ciphercontext, 0, sizeof(ciphercontext));
+
+	/* Destroy temporary data. */
+	memset(buf, 0, sizeof(buf));
+	buffer_free(&buffer);
+
+	fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
+	if (fd < 0) {
+		error("open %s failed: %s.", filename, strerror(errno));
+		buffer_free(&encrypted);
+		return 0;
+	}
+	if (atomicio(vwrite, fd, buffer_ptr(&encrypted),
+	    buffer_len(&encrypted)) != buffer_len(&encrypted)) {
+		error("write to key file %s failed: %s", filename,
+		    strerror(errno));
+		buffer_free(&encrypted);
+		close(fd);
+		unlink(filename);
+		return 0;
+	}
+	close(fd);
+	buffer_free(&encrypted);
+	return 1;
+}
+
+/* save SSH v2 key in OpenSSL PEM format */
+static int
+key_save_private_pem(Key *key, const char *filename, const char *_passphrase,
+    const char *comment)
+{
+	FILE *fp;
+	int fd;
+	int success = 0;
+	int len = strlen(_passphrase);
+	u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL;
+	const EVP_CIPHER *cipher = (len > 0) ? EVP_des_ede3_cbc() : NULL;
+
+	if (len > 0 && len <= 4) {
+		error("passphrase too short: have %d bytes, need > 4", len);
+		return 0;
+	}
+	fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
+	if (fd < 0) {
+		error("open %s failed: %s.", filename, strerror(errno));
+		return 0;
+	}
+	fp = fdopen(fd, "w");
+	if (fp == NULL) {
+		error("fdopen %s failed: %s.", filename, strerror(errno));
+		close(fd);
+		return 0;
+	}
+	switch (key->type) {
+	case KEY_DSA:
+		success = PEM_write_DSAPrivateKey(fp, key->dsa,
+		    cipher, passphrase, len, NULL, NULL);
+		break;
+	case KEY_RSA:
+		success = PEM_write_RSAPrivateKey(fp, key->rsa,
+		    cipher, passphrase, len, NULL, NULL);
+		break;
+	}
+	fclose(fp);
+	return success;
+}
+
+int
+key_save_private(Key *key, const char *filename, const char *passphrase,
+    const char *comment)
+{
+	switch (key->type) {
+	case KEY_RSA1:
+		return key_save_private_rsa1(key, filename, passphrase,
+		    comment);
+	case KEY_DSA:
+	case KEY_RSA:
+		return key_save_private_pem(key, filename, passphrase,
+		    comment);
+	default:
+		break;
+	}
+	error("key_save_private: cannot save key type %d", key->type);
+	return 0;
+}
+
+/*
+ * Loads the public part of the ssh v1 key file.  Returns NULL if an error was
+ * encountered (the file does not exist or is not readable), and the key
+ * otherwise.
+ */
+
+static Key *
+key_load_public_rsa1(int fd, const char *filename, char **commentp)
+{
+	Buffer buffer;
+	Key *pub;
+	struct stat st;
+	char *cp;
+	u_int i;
+	size_t len;
+
+	if (fstat(fd, &st) < 0) {
+		error("fstat for key file %.200s failed: %.100s",
+		    filename, strerror(errno));
+		return NULL;
+	}
+	if (st.st_size > 1*1024*1024) {
+		error("key file %.200s too large", filename);
+		return NULL;
+	}
+	len = (size_t)st.st_size;		/* truncated */
+
+	buffer_init(&buffer);
+	cp = buffer_append_space(&buffer, len);
+
+	if (atomicio(read, fd, cp, len) != len) {
+		debug("Read from key file %.200s failed: %.100s", filename,
+		    strerror(errno));
+		buffer_free(&buffer);
+		return NULL;
+	}
+
+	/* Check that it is at least big enough to contain the ID string. */
+	if (len < sizeof(authfile_id_string)) {
+		debug3("Not a RSA1 key file %.200s.", filename);
+		buffer_free(&buffer);
+		return NULL;
+	}
+	/*
+	 * Make sure it begins with the id string.  Consume the id string
+	 * from the buffer.
+	 */
+	for (i = 0; i < sizeof(authfile_id_string); i++)
+		if (buffer_get_char(&buffer) != authfile_id_string[i]) {
+			debug3("Not a RSA1 key file %.200s.", filename);
+			buffer_free(&buffer);
+			return NULL;
+		}
+	/* Skip cipher type and reserved data. */
+	(void) buffer_get_char(&buffer);	/* cipher type */
+	(void) buffer_get_int(&buffer);		/* reserved */
+
+	/* Read the public key from the buffer. */
+	(void) buffer_get_int(&buffer);
+	pub = key_new(KEY_RSA1);
+	buffer_get_bignum(&buffer, pub->rsa->n);
+	buffer_get_bignum(&buffer, pub->rsa->e);
+	if (commentp)
+		*commentp = buffer_get_string(&buffer, NULL);
+	/* The encrypted private part is not parsed by this function. */
+
+	buffer_free(&buffer);
+	return pub;
+}
+
+/* load public key from private-key file, works only for SSH v1 */
+Key *
+key_load_public_type(int type, const char *filename, char **commentp)
+{
+	Key *pub;
+	int fd;
+
+	if (type == KEY_RSA1) {
+		fd = open(filename, O_RDONLY);
+		if (fd < 0)
+			return NULL;
+		pub = key_load_public_rsa1(fd, filename, commentp);
+		close(fd);
+		return pub;
+	}
+	return NULL;
+}
+
+/*
+ * Loads the private key from the file.  Returns 0 if an error is encountered
+ * (file does not exist or is not readable, or passphrase is bad). This
+ * initializes the private key.
+ * Assumes we are called under uid of the owner of the file.
+ */
+
+static Key *
+key_load_private_rsa1(int fd, const char *filename, const char *passphrase,
+    char **commentp)
+{
+	u_int i;
+	int check1, check2, cipher_type;
+	size_t len;
+	Buffer buffer, decrypted;
+	u_char *cp;
+	CipherContext ciphercontext;
+	Cipher *cipher;
+	Key *prv = NULL;
+	struct stat st;
+
+	if (fstat(fd, &st) < 0) {
+		error("fstat for key file %.200s failed: %.100s",
+		    filename, strerror(errno));
+		close(fd);
+		return NULL;
+	}
+	if (st.st_size > 1*1024*1024) {
+		error("key file %.200s too large", filename);
+		close(fd);
+		return (NULL);
+	}
+	len = (size_t)st.st_size;		/* truncated */
+
+	buffer_init(&buffer);
+	cp = buffer_append_space(&buffer, len);
+
+	if (atomicio(read, fd, cp, len) != len) {
+		debug("Read from key file %.200s failed: %.100s", filename,
+		    strerror(errno));
+		buffer_free(&buffer);
+		close(fd);
+		return NULL;
+	}
+
+	/* Check that it is at least big enough to contain the ID string. */
+	if (len < sizeof(authfile_id_string)) {
+		debug3("Not a RSA1 key file %.200s.", filename);
+		buffer_free(&buffer);
+		close(fd);
+		return NULL;
+	}
+	/*
+	 * Make sure it begins with the id string.  Consume the id string
+	 * from the buffer.
+	 */
+	for (i = 0; i < sizeof(authfile_id_string); i++)
+		if (buffer_get_char(&buffer) != authfile_id_string[i]) {
+			debug3("Not a RSA1 key file %.200s.", filename);
+			buffer_free(&buffer);
+			close(fd);
+			return NULL;
+		}
+
+	/* Read cipher type. */
+	cipher_type = buffer_get_char(&buffer);
+	(void) buffer_get_int(&buffer);	/* Reserved data. */
+
+	/* Read the public key from the buffer. */
+	(void) buffer_get_int(&buffer);
+	prv = key_new_private(KEY_RSA1);
+
+	buffer_get_bignum(&buffer, prv->rsa->n);
+	buffer_get_bignum(&buffer, prv->rsa->e);
+	if (commentp)
+		*commentp = buffer_get_string(&buffer, NULL);
+	else
+		xfree(buffer_get_string(&buffer, NULL));
+
+	/* Check that it is a supported cipher. */
+	cipher = cipher_by_number(cipher_type);
+	if (cipher == NULL) {
+		debug("Unsupported cipher %d used in key file %.200s.",
+		    cipher_type, filename);
+		buffer_free(&buffer);
+		goto fail;
+	}
+	/* Initialize space for decrypted data. */
+	buffer_init(&decrypted);
+	cp = buffer_append_space(&decrypted, buffer_len(&buffer));
+
+	/* Rest of the buffer is encrypted.  Decrypt it using the passphrase. */
+	cipher_set_key_string(&ciphercontext, cipher, passphrase,
+	    CIPHER_DECRYPT);
+	cipher_crypt(&ciphercontext, cp,
+	    buffer_ptr(&buffer), buffer_len(&buffer));
+	cipher_cleanup(&ciphercontext);
+	memset(&ciphercontext, 0, sizeof(ciphercontext));
+	buffer_free(&buffer);
+
+	check1 = buffer_get_char(&decrypted);
+	check2 = buffer_get_char(&decrypted);
+	if (check1 != buffer_get_char(&decrypted) ||
+	    check2 != buffer_get_char(&decrypted)) {
+		if (strcmp(passphrase, "") != 0)
+			debug("Bad passphrase supplied for key file %.200s.",
+			    filename);
+		/* Bad passphrase. */
+		buffer_free(&decrypted);
+		goto fail;
+	}
+	/* Read the rest of the private key. */
+	buffer_get_bignum(&decrypted, prv->rsa->d);
+	buffer_get_bignum(&decrypted, prv->rsa->iqmp);		/* u */
+	/* in SSL and SSH v1 p and q are exchanged */
+	buffer_get_bignum(&decrypted, prv->rsa->q);		/* p */
+	buffer_get_bignum(&decrypted, prv->rsa->p);		/* q */
+
+	/* calculate p-1 and q-1 */
+	rsa_generate_additional_parameters(prv->rsa);
+
+	buffer_free(&decrypted);
+
+	/* enable blinding */
+	if (RSA_blinding_on(prv->rsa, NULL) != 1) {
+		error("key_load_private_rsa1: RSA_blinding_on failed");
+		goto fail;
+	}
+	close(fd);
+	return prv;
+
+fail:
+	if (commentp)
+		xfree(*commentp);
+	close(fd);
+	key_free(prv);
+	return NULL;
+}
+
+Key *
+key_load_private_pem(int fd, int type, const char *passphrase,
+    char **commentp)
+{
+	FILE *fp;
+	EVP_PKEY *pk = NULL;
+	Key *prv = NULL;
+	char *name = "<no key>";
+
+	fp = fdopen(fd, "r");
+	if (fp == NULL) {
+		error("fdopen failed: %s", strerror(errno));
+		close(fd);
+		return NULL;
+	}
+	pk = PEM_read_PrivateKey(fp, NULL, NULL, (char *)passphrase);
+	if (pk == NULL) {
+		debug("PEM_read_PrivateKey failed");
+		(void)ERR_get_error();
+	} else if (pk->type == EVP_PKEY_RSA &&
+	    (type == KEY_UNSPEC||type==KEY_RSA)) {
+		prv = key_new(KEY_UNSPEC);
+		prv->rsa = EVP_PKEY_get1_RSA(pk);
+		prv->type = KEY_RSA;
+		name = "rsa w/o comment";
+#ifdef DEBUG_PK
+		RSA_print_fp(stderr, prv->rsa, 8);
+#endif
+		if (RSA_blinding_on(prv->rsa, NULL) != 1) {
+			error("key_load_private_pem: RSA_blinding_on failed");
+			key_free(prv);
+			prv = NULL;
+		}
+	} else if (pk->type == EVP_PKEY_DSA &&
+	    (type == KEY_UNSPEC||type==KEY_DSA)) {
+		prv = key_new(KEY_UNSPEC);
+		prv->dsa = EVP_PKEY_get1_DSA(pk);
+		prv->type = KEY_DSA;
+		name = "dsa w/o comment";
+#ifdef DEBUG_PK
+		DSA_print_fp(stderr, prv->dsa, 8);
+#endif
+	} else {
+		error("PEM_read_PrivateKey: mismatch or "
+		    "unknown EVP_PKEY save_type %d", pk->save_type);
+	}
+	fclose(fp);
+	if (pk != NULL)
+		EVP_PKEY_free(pk);
+	if (prv != NULL && commentp)
+		*commentp = xstrdup(name);
+	debug("read PEM private key done: type %s",
+	    prv ? key_type(prv) : "<unknown>");
+	return prv;
+}
+
+int
+key_perm_ok(int fd, const char *filename)
+{
+	struct stat st;
+
+	if (fstat(fd, &st) < 0)
+		return 0;
+	/*
+	 * if a key owned by the user is accessed, then we check the
+	 * permissions of the file. if the key owned by a different user,
+	 * then we don't care.
+	 */
+#ifdef HAVE_CYGWIN
+	if (check_ntsec(filename))
+#endif
+	if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) {
+		error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
+		error("@         WARNING: UNPROTECTED PRIVATE KEY FILE!          @");
+		error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
+		error("Permissions 0%3.3o for '%s' are too open.",
+		    (u_int)st.st_mode & 0777, filename);
+		error("It is recommended that your private key files are NOT accessible by others.");
+		error("This private key will be ignored.");
+		return 0;
+	}
+	return 1;
+}
+
+Key *
+key_load_private_type(int type, const char *filename, const char *passphrase,
+    char **commentp, int *perm_ok)
+{
+	int fd;
+
+	fd = open(filename, O_RDONLY);
+	if (fd < 0)
+		return NULL;
+	if (!key_perm_ok(fd, filename)) {
+		if (perm_ok != NULL)
+			*perm_ok = 0;
+		error("bad permissions: ignore key: %s", filename);
+		close(fd);
+		return NULL;
+	}
+	if (perm_ok != NULL)
+		*perm_ok = 1;
+	switch (type) {
+	case KEY_RSA1:
+		return key_load_private_rsa1(fd, filename, passphrase,
+		    commentp);
+		/* closes fd */
+	case KEY_DSA:
+	case KEY_RSA:
+	case KEY_UNSPEC:
+		return key_load_private_pem(fd, type, passphrase, commentp);
+		/* closes fd */
+	default:
+		close(fd);
+		break;
+	}
+	return NULL;
+}
+
+Key *
+key_load_private(const char *filename, const char *passphrase,
+    char **commentp)
+{
+	Key *pub, *prv;
+	int fd;
+
+	fd = open(filename, O_RDONLY);
+	if (fd < 0)
+		return NULL;
+	if (!key_perm_ok(fd, filename)) {
+		error("bad permissions: ignore key: %s", filename);
+		close(fd);
+		return NULL;
+	}
+	pub = key_load_public_rsa1(fd, filename, commentp);
+	lseek(fd, (off_t) 0, SEEK_SET);		/* rewind */
+	if (pub == NULL) {
+		/* closes fd */
+		prv = key_load_private_pem(fd, KEY_UNSPEC, passphrase, NULL);
+		/* use the filename as a comment for PEM */
+		if (commentp && prv)
+			*commentp = xstrdup(filename);
+	} else {
+		/* it's a SSH v1 key if the public key part is readable */
+		key_free(pub);
+		/* closes fd */
+		prv = key_load_private_rsa1(fd, filename, passphrase, NULL);
+	}
+	return prv;
+}
+
+static int
+key_try_load_public(Key *k, const char *filename, char **commentp)
+{
+	FILE *f;
+	char line[SSH_MAX_PUBKEY_BYTES];
+	char *cp;
+	u_long linenum = 0;
+
+	f = fopen(filename, "r");
+	if (f != NULL) {
+		while (read_keyfile_line(f, filename, line, sizeof(line),
+			    &linenum) != -1) {
+			cp = line;
+			switch (*cp) {
+			case '#':
+			case '\n':
+			case '\0':
+				continue;
+			}
+			/* Skip leading whitespace. */
+			for (; *cp && (*cp == ' ' || *cp == '\t'); cp++)
+				;
+			if (*cp) {
+				if (key_read(k, &cp) == 1) {
+					if (commentp)
+						*commentp=xstrdup(filename);
+					fclose(f);
+					return 1;
+				}
+			}
+		}
+		fclose(f);
+	}
+	return 0;
+}
+
+/* load public key from ssh v1 private or any pubkey file */
+Key *
+key_load_public(const char *filename, char **commentp)
+{
+	Key *pub;
+	char file[MAXPATHLEN];
+
+	/* try rsa1 private key */
+	pub = key_load_public_type(KEY_RSA1, filename, commentp);
+	if (pub != NULL)
+		return pub;
+
+	/* try rsa1 public key */
+	pub = key_new(KEY_RSA1);
+	if (key_try_load_public(pub, filename, commentp) == 1)
+		return pub;
+	key_free(pub);
+
+	/* try ssh2 public key */
+	pub = key_new(KEY_UNSPEC);
+	if (key_try_load_public(pub, filename, commentp) == 1)
+		return pub;
+	if ((strlcpy(file, filename, sizeof file) < sizeof(file)) &&
+	    (strlcat(file, ".pub", sizeof file) < sizeof(file)) &&
+	    (key_try_load_public(pub, file, commentp) == 1))
+		return pub;
+	key_free(pub);
+	return NULL;
+}