/*
- *
- * hostfile.c
- *
* Author: Tatu Ylonen <ylo@cs.hut.fi>
- *
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
- *
- * Created: Thu Jun 29 07:10:56 1995 ylo
- *
* Functions for manipulating the known hosts files.
- *
+ *
+ * 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) 1999, 2000 Markus Friedl. All rights reserved.
+ * Copyright (c) 1999 Niels Provos. 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"
-RCSID("$Id$");
+RCSID("$OpenBSD: hostfile.c,v 1.31 2003/04/08 20:21:28 itojun Exp $");
#include "packet.h"
-#include "ssh.h"
+#include "match.h"
+#include "key.h"
+#include "hostfile.h"
+#include "log.h"
/*
- * Reads a multiple-precision integer in hex from the buffer, and advances
- * the pointer. The integer must already be initialized. This function is
- * permitted to modify the buffer. This leaves *cpp to point just beyond the
- * last processed (and maybe modified) character. Note that this may modify
- * the buffer containing the number.
+ * Parses an RSA (number of bits, e, n) or DSA key from a string. Moves the
+ * pointer over the key. Skips any whitespace at the beginning and at end.
*/
int
-auth_rsa_read_bignum(char **cpp, BIGNUM * value)
+hostfile_read_key(char **cpp, u_int *bitsp, Key *ret)
{
- char *cp = *cpp;
- int len, old;
-
- /* Skip any leading whitespace. */
- for (; *cp == ' ' || *cp == '\t'; cp++)
- ;
-
- /* Check that it begins with a hex digit. */
- if (*cp < '0' || *cp > '9')
- return 0;
-
- /* Save starting position. */
- *cpp = cp;
-
- /* Move forward until all hex digits skipped. */
- for (; *cp >= '0' && *cp <= '9'; cp++)
- ;
-
- /* Compute the length of the hex number. */
- len = cp - *cpp;
-
- /* Save the old terminating character, and replace it by \0. */
- old = *cp;
- *cp = 0;
-
- /* Parse the number. */
- if (BN_dec2bn(&value, *cpp) == 0)
- return 0;
-
- /* Restore old terminating character. */
- *cp = old;
-
- /* Move beyond the number and return success. */
- *cpp = cp;
- return 1;
-}
-
-/*
- * Parses an RSA key (number of bits, e, n) from a string. Moves the pointer
- * over the key. Skips any whitespace at the beginning and at end.
- */
-
-int
-auth_rsa_read_key(char **cpp, unsigned int *bitsp, BIGNUM * e, BIGNUM * n)
-{
- unsigned int bits;
char *cp;
/* Skip leading whitespace. */
for (cp = *cpp; *cp == ' ' || *cp == '\t'; cp++)
;
- /* Get number of bits. */
- if (*cp < '0' || *cp > '9')
- return 0; /* Bad bit count... */
- for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
- bits = 10 * bits + *cp - '0';
-
- /* Get public exponent. */
- if (!auth_rsa_read_bignum(&cp, e))
- return 0;
-
- /* Get public modulus. */
- if (!auth_rsa_read_bignum(&cp, n))
+ if (key_read(ret, &cp) != 1)
return 0;
/* Skip trailing whitespace. */
/* Return results. */
*cpp = cp;
- *bitsp = bits;
+ *bitsp = key_size(ret);
return 1;
}
-/*
- * Tries to match the host name (which must be in all lowercase) against the
- * comma-separated sequence of subpatterns (each possibly preceded by ! to
- * indicate negation). Returns true if there is a positive match; zero
- * otherwise.
- */
-
-int
-match_hostname(const char *host, const char *pattern, unsigned int len)
+static int
+hostfile_check_key(int bits, Key *key, const char *host, const char *filename, int linenum)
{
- char sub[1024];
- int negated;
- int got_positive;
- unsigned int i, subi;
-
- got_positive = 0;
- for (i = 0; i < len;) {
- /* Check if the subpattern is negated. */
- if (pattern[i] == '!') {
- negated = 1;
- i++;
- } else
- negated = 0;
-
- /*
- * Extract the subpattern up to a comma or end. Convert the
- * subpattern to lowercase.
- */
- for (subi = 0;
- i < len && subi < sizeof(sub) - 1 && pattern[i] != ',';
- subi++, i++)
- sub[subi] = isupper(pattern[i]) ? tolower(pattern[i]) : pattern[i];
- /* If subpattern too long, return failure (no match). */
- if (subi >= sizeof(sub) - 1)
- return 0;
-
- /* If the subpattern was terminated by a comma, skip the comma. */
- if (i < len && pattern[i] == ',')
- i++;
-
- /* Null-terminate the subpattern. */
- sub[subi] = '\0';
-
- /* Try to match the subpattern against the host name. */
- if (match_pattern(host, sub)) {
- if (negated)
- return 0; /* Fail */
- else
- got_positive = 1;
- }
+ if (key == NULL || key->type != KEY_RSA1 || key->rsa == NULL)
+ return 1;
+ if (bits != BN_num_bits(key->rsa->n)) {
+ logit("Warning: %s, line %d: keysize mismatch for host %s: "
+ "actual %d vs. announced %d.",
+ filename, linenum, host, BN_num_bits(key->rsa->n), bits);
+ logit("Warning: replace %d with %d in %s, line %d.",
+ bits, BN_num_bits(key->rsa->n), filename, linenum);
}
-
- /*
- * Return success if got a positive match. If there was a negative
- * match, we have already returned zero and never get here.
- */
- return got_positive;
+ return 1;
}
/*
* in the list of our known hosts. Returns HOST_OK if the host is known and
* has the specified key, HOST_NEW if the host is not known, and HOST_CHANGED
* if the host is known but used to have a different host key.
+ *
+ * If no 'key' has been specified and a key of type 'keytype' is known
+ * for the specified host, then HOST_FOUND is returned.
*/
-HostStatus
-check_host_in_hostfile(const char *filename, const char *host,
- BIGNUM * e, BIGNUM * n, BIGNUM * ke, BIGNUM * kn)
+static HostStatus
+check_host_in_hostfile_by_key_or_type(const char *filename,
+ const char *host, Key *key, int keytype, Key *found, int *numret)
{
FILE *f;
char line[8192];
int linenum = 0;
- unsigned int bits, kbits, hostlen;
+ u_int kbits;
char *cp, *cp2;
HostStatus end_return;
+ debug3("check_host_in_hostfile: filename %s", filename);
+
/* Open the file containing the list of known hosts. */
f = fopen(filename, "r");
if (!f)
return HOST_NEW;
- /* Cache the length of the host name. */
- hostlen = strlen(host);
-
/*
* Return value when the loop terminates. This is set to
* HOST_CHANGED if we have seen a different key for the host and have
*/
end_return = HOST_NEW;
- /* size of modulus 'n' */
- bits = BN_num_bits(n);
-
- /* Go trough the file. */
+ /* Go through the file. */
while (fgets(line, sizeof(line), f)) {
cp = line;
linenum++;
;
/* Check if the host name matches. */
- if (!match_hostname(host, cp, (unsigned int) (cp2 - cp)))
+ if (match_hostname(host, cp, (u_int) (cp2 - cp)) != 1)
continue;
/* Got a match. Skip host name. */
* Extract the key from the line. This will skip any leading
* whitespace. Ignore badly formatted lines.
*/
- if (!auth_rsa_read_key(&cp, &kbits, ke, kn))
+ if (!hostfile_read_key(&cp, &kbits, found))
continue;
- if (kbits != BN_num_bits(kn)) {
- error("Warning: error in %s, line %d: keysize mismatch for host %s: "
- "actual size %d vs. announced %d.",
- filename, linenum, host, BN_num_bits(kn), kbits);
- error("Warning: replace %d with %d in %s, line %d.",
- kbits, BN_num_bits(kn), filename, linenum);
+ if (numret != NULL)
+ *numret = linenum;
+
+ if (key == NULL) {
+ /* we found a key of the requested type */
+ if (found->type == keytype)
+ return HOST_FOUND;
+ continue;
}
+
+ if (!hostfile_check_key(kbits, found, host, filename, linenum))
+ continue;
+
/* Check if the current key is the same as the given key. */
- if (BN_cmp(ke, e) == 0 && BN_cmp(kn, n) == 0) {
+ if (key_equal(key, found)) {
/* Ok, they match. */
+ debug3("check_host_in_hostfile: match line %d", linenum);
fclose(f);
return HOST_OK;
}
return end_return;
}
+HostStatus
+check_host_in_hostfile(const char *filename, const char *host, Key *key,
+ Key *found, int *numret)
+{
+ if (key == NULL)
+ fatal("no key to look up");
+ return (check_host_in_hostfile_by_key_or_type(filename, host, key, 0,
+ found, numret));
+}
+
+int
+lookup_key_in_hostfile_by_type(const char *filename, const char *host,
+ int keytype, Key *found, int *numret)
+{
+ return (check_host_in_hostfile_by_key_or_type(filename, host, NULL,
+ keytype, found, numret) == HOST_FOUND);
+}
+
/*
* Appends an entry to the host file. Returns false if the entry could not
* be appended.
*/
int
-add_host_to_hostfile(const char *filename, const char *host,
- BIGNUM * e, BIGNUM * n)
+add_host_to_hostfile(const char *filename, const char *host, Key *key)
{
FILE *f;
- char *buf;
- unsigned int bits;
-
- /* Open the file for appending. */
+ int success = 0;
+ if (key == NULL)
+ return 1; /* XXX ? */
f = fopen(filename, "a");
if (!f)
return 0;
-
- /* size of modulus 'n' */
- bits = BN_num_bits(n);
-
- /* Print the host name and key to the file. */
- fprintf(f, "%s %u ", host, bits);
- buf = BN_bn2dec(e);
- if (buf == NULL) {
- error("add_host_to_hostfile: BN_bn2dec(e) failed");
- fclose(f);
- return 0;
+ fprintf(f, "%s ", host);
+ if (key_write(key, f)) {
+ success = 1;
+ } else {
+ error("add_host_to_hostfile: saving key in %s failed", filename);
}
- fprintf(f, "%s ", buf);
- free(buf);
- buf = BN_bn2dec(n);
- if (buf == NULL) {
- error("add_host_to_hostfile: BN_bn2dec(n) failed");
- fclose(f);
- return 0;
- }
- fprintf(f, "%s\n", buf);
- free(buf);
-
- /* Close the file. */
+ fprintf(f, "\n");
fclose(f);
- return 1;
+ return success;
}