diff options
Diffstat (limited to 'crypto/openssh/hostfile.c')
-rw-r--r-- | crypto/openssh/hostfile.c | 302 |
1 files changed, 177 insertions, 125 deletions
diff --git a/crypto/openssh/hostfile.c b/crypto/openssh/hostfile.c index afab6da..b6f924b 100644 --- a/crypto/openssh/hostfile.c +++ b/crypto/openssh/hostfile.c @@ -1,4 +1,4 @@ -/* $OpenBSD: hostfile.c,v 1.48 2010/03/04 10:36:03 djm Exp $ */ +/* $OpenBSD: hostfile.c,v 1.50 2010/12/04 13:31:37 djm Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -56,6 +56,12 @@ #include "key.h" #include "hostfile.h" #include "log.h" +#include "misc.h" + +struct hostkeys { + struct hostkey_entry *entries; + u_int num_entries; +}; static int extract_salt(const char *s, u_int l, char *salt, size_t salt_len) @@ -164,26 +170,28 @@ hostfile_read_key(char **cpp, u_int *bitsp, Key *ret) /* Return results. */ *cpp = cp; - *bitsp = key_size(ret); + if (bitsp != NULL) + *bitsp = key_size(ret); return 1; } static int -hostfile_check_key(int bits, const Key *key, const char *host, const char *filename, int linenum) +hostfile_check_key(int bits, const Key *key, const char *host, + const char *filename, u_long linenum) { 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: " + logit("Warning: %s, line %lu: 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.", + logit("Warning: replace %d with %d in %s, line %lu.", bits, BN_num_bits(key->rsa->n), filename, linenum); } return 1; } -static enum { MRK_ERROR, MRK_NONE, MRK_REVOKE, MRK_CA } +static HostkeyMarker check_markers(char **cpp) { char marker[32], *sp, *cp = *cpp; @@ -218,49 +226,32 @@ check_markers(char **cpp) return ret; } -/* - * Checks whether the given host (which must be in all lowercase) is already - * 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. - */ +struct hostkeys * +init_hostkeys(void) +{ + struct hostkeys *ret = xcalloc(1, sizeof(*ret)); -static HostStatus -check_host_in_hostfile_by_key_or_type(const char *filename, - const char *host, const Key *key, int keytype, Key *found, - int want_revocation, int *numret) + ret->entries = NULL; + return ret; +} + +void +load_hostkeys(struct hostkeys *hostkeys, const char *host, const char *path) { FILE *f; char line[8192]; - int want, have, linenum = 0, want_cert = key_is_cert(key); - u_int kbits; + u_long linenum = 0, num_loaded = 0; char *cp, *cp2, *hashed_host; - HostStatus end_return; - - debug3("check_host_in_hostfile: host %s filename %s", host, filename); - - if (want_revocation && (key == NULL || keytype != 0 || found != NULL)) - fatal("%s: invalid arguments", __func__); - - /* Open the file containing the list of known hosts. */ - f = fopen(filename, "r"); - if (!f) - return HOST_NEW; - - /* - * Return value when the loop terminates. This is set to - * HOST_CHANGED if we have seen a different key for the host and have - * not found the proper one. - */ - end_return = HOST_NEW; - - /* Go through the file. */ - while (fgets(line, sizeof(line), f)) { + HostkeyMarker marker; + Key *key; + int kbits; + + if ((f = fopen(path, "r")) == NULL) + return; + debug3("%s: loading entries for host \"%.100s\" from file \"%s\"", + __func__, host, path); + while (read_keyfile_line(f, path, line, sizeof(line), &linenum) == 0) { cp = line; - linenum++; /* Skip any leading whitespace, comments and empty lines. */ for (; *cp == ' ' || *cp == '\t'; cp++) @@ -268,19 +259,11 @@ check_host_in_hostfile_by_key_or_type(const char *filename, if (!*cp || *cp == '#' || *cp == '\n') continue; - if (want_revocation) - want = MRK_REVOKE; - else if (want_cert) - want = MRK_CA; - else - want = MRK_NONE; - - if ((have = check_markers(&cp)) == MRK_ERROR) { - verbose("%s: invalid marker at %s:%d", - __func__, filename, linenum); - continue; - } else if (want != have) + if ((marker = check_markers(&cp)) == MRK_ERROR) { + verbose("%s: invalid marker at %s:%lu", + __func__, path, linenum); continue; + } /* Find the end of the host name portion. */ for (cp2 = cp; *cp2 && *cp2 != ' ' && *cp2 != '\t'; cp2++) @@ -292,8 +275,8 @@ check_host_in_hostfile_by_key_or_type(const char *filename, continue; hashed_host = host_hash(host, cp, (u_int) (cp2 - cp)); if (hashed_host == NULL) { - debug("Invalid hashed host line %d of %s", - linenum, filename); + debug("Invalid hashed host line %lu of %s", + linenum, path); continue; } if (strncmp(hashed_host, cp, (u_int) (cp2 - cp)) != 0) @@ -303,98 +286,167 @@ check_host_in_hostfile_by_key_or_type(const char *filename, /* Got a match. Skip host name. */ cp = cp2; - if (want_revocation) - found = key_new(KEY_UNSPEC); - /* * Extract the key from the line. This will skip any leading * whitespace. Ignore badly formatted lines. */ - if (!hostfile_read_key(&cp, &kbits, found)) + key = key_new(KEY_UNSPEC); + if (!hostfile_read_key(&cp, &kbits, key)) { + key_free(key); + key = key_new(KEY_RSA1); + if (!hostfile_read_key(&cp, &kbits, key)) { + key_free(key); + continue; + } + } + if (!hostfile_check_key(kbits, key, host, path, linenum)) continue; - if (numret != NULL) - *numret = linenum; + debug3("%s: found %skey type %s in file %s:%lu", __func__, + marker == MRK_NONE ? "" : + (marker == MRK_CA ? "ca " : "revoked "), + key_type(key), path, linenum); + hostkeys->entries = xrealloc(hostkeys->entries, + hostkeys->num_entries + 1, sizeof(*hostkeys->entries)); + hostkeys->entries[hostkeys->num_entries].host = xstrdup(host); + hostkeys->entries[hostkeys->num_entries].file = xstrdup(path); + hostkeys->entries[hostkeys->num_entries].line = linenum; + hostkeys->entries[hostkeys->num_entries].key = key; + hostkeys->entries[hostkeys->num_entries].marker = marker; + hostkeys->num_entries++; + num_loaded++; + } + debug3("%s: loaded %lu keys", __func__, num_loaded); + fclose(f); + return; +} - if (key == NULL) { - /* we found a key of the requested type */ - if (found->type == keytype) { - fclose(f); - return HOST_FOUND; - } - continue; - } +void +free_hostkeys(struct hostkeys *hostkeys) +{ + u_int i; + + for (i = 0; i < hostkeys->num_entries; i++) { + xfree(hostkeys->entries[i].host); + xfree(hostkeys->entries[i].file); + key_free(hostkeys->entries[i].key); + bzero(hostkeys->entries + i, sizeof(*hostkeys->entries)); + } + if (hostkeys->entries != NULL) + xfree(hostkeys->entries); + hostkeys->entries = NULL; + hostkeys->num_entries = 0; + xfree(hostkeys); +} + +static int +check_key_not_revoked(struct hostkeys *hostkeys, Key *k) +{ + int is_cert = key_is_cert(k); + u_int i; - if (!hostfile_check_key(kbits, found, host, filename, linenum)) + for (i = 0; i < hostkeys->num_entries; i++) { + if (hostkeys->entries[i].marker != MRK_REVOKE) continue; + if (key_equal_public(k, hostkeys->entries[i].key)) + return -1; + if (is_cert && + key_equal_public(k->cert->signature_key, + hostkeys->entries[i].key)) + return -1; + } + return 0; +} - if (want_revocation) { - if (key_is_cert(key) && - key_equal_public(key->cert->signature_key, found)) { - verbose("check_host_in_hostfile: revoked CA " - "line %d", linenum); - key_free(found); - return HOST_REVOKED; - } - if (key_equal_public(key, found)) { - verbose("check_host_in_hostfile: revoked key " - "line %d", linenum); - key_free(found); - return HOST_REVOKED; - } - key_free(found); +/* + * Match keys against a specified key, or look one up by key type. + * + * If looking for a keytype (key == NULL) and one is found then return + * HOST_FOUND, otherwise HOST_NEW. + * + * If looking for a key (key != NULL): + * 1. If the key is a cert and a matching CA is found, return HOST_OK + * 2. If the key is not a cert and a matching key is found, return HOST_OK + * 3. If no key matches but a key with a different type is found, then + * return HOST_CHANGED + * 4. If no matching keys are found, then return HOST_NEW. + * + * Finally, check any found key is not revoked. + */ +static HostStatus +check_hostkeys_by_key_or_type(struct hostkeys *hostkeys, + Key *k, int keytype, const struct hostkey_entry **found) +{ + u_int i; + HostStatus end_return = HOST_NEW; + int want_cert = key_is_cert(k); + HostkeyMarker want_marker = want_cert ? MRK_CA : MRK_NONE; + int proto = (k ? k->type : keytype) == KEY_RSA1 ? 1 : 2; + + if (found != NULL) + *found = NULL; + + for (i = 0; i < hostkeys->num_entries; i++) { + if (proto == 1 && hostkeys->entries[i].key->type != KEY_RSA1) + continue; + if (proto == 2 && hostkeys->entries[i].key->type == KEY_RSA1) continue; + if (hostkeys->entries[i].marker != want_marker) + continue; + if (k == NULL) { + if (hostkeys->entries[i].key->type != keytype) + continue; + end_return = HOST_FOUND; + if (found != NULL) + *found = hostkeys->entries + i; + k = hostkeys->entries[i].key; + break; } - - /* Check if the current key is the same as the given key. */ - if (want_cert && key_equal(key->cert->signature_key, found)) { - /* Found CA cert for key */ - debug3("check_host_in_hostfile: CA match line %d", - linenum); - fclose(f); - return HOST_OK; - } else if (!want_cert && key_equal(key, found)) { - /* Found identical key */ - debug3("check_host_in_hostfile: match line %d", linenum); - fclose(f); - return HOST_OK; + if (want_cert) { + if (key_equal_public(k->cert->signature_key, + hostkeys->entries[i].key)) { + /* A matching CA exists */ + end_return = HOST_OK; + if (found != NULL) + *found = hostkeys->entries + i; + break; + } + } else { + if (key_equal(k, hostkeys->entries[i].key)) { + end_return = HOST_OK; + if (found != NULL) + *found = hostkeys->entries + i; + break; + } + /* A non-maching key exists */ + end_return = HOST_CHANGED; + if (found != NULL) + *found = hostkeys->entries + i; } - /* - * They do not match. We will continue to go through the - * file; however, we note that we will not return that it is - * new. - */ - end_return = HOST_CHANGED; } - /* Clear variables and close the file. */ - fclose(f); - - /* - * Return either HOST_NEW or HOST_CHANGED, depending on whether we - * saw a different key for the host. - */ + if (check_key_not_revoked(hostkeys, k) != 0) { + end_return = HOST_REVOKED; + if (found != NULL) + *found = NULL; + } return end_return; } - + HostStatus -check_host_in_hostfile(const char *filename, const char *host, const Key *key, - Key *found, int *numret) +check_key_in_hostkeys(struct hostkeys *hostkeys, Key *key, + const struct hostkey_entry **found) { if (key == NULL) fatal("no key to look up"); - if (check_host_in_hostfile_by_key_or_type(filename, host, - key, 0, NULL, 1, NULL) == HOST_REVOKED) - return HOST_REVOKED; - return check_host_in_hostfile_by_key_or_type(filename, host, key, 0, - found, 0, numret); + return check_hostkeys_by_key_or_type(hostkeys, key, 0, found); } int -lookup_key_in_hostfile_by_type(const char *filename, const char *host, - int keytype, Key *found, int *numret) +lookup_key_in_hostkeys_by_type(struct hostkeys *hostkeys, int keytype, + const struct hostkey_entry **found) { - return (check_host_in_hostfile_by_key_or_type(filename, host, NULL, - keytype, found, 0, numret) == HOST_FOUND); + return (check_hostkeys_by_key_or_type(hostkeys, NULL, keytype, + found) == HOST_FOUND); } /* |