diff options
Diffstat (limited to 'crypto/openssh/ssh-keysign.c')
| -rw-r--r-- | crypto/openssh/ssh-keysign.c | 161 |
1 files changed, 99 insertions, 62 deletions
diff --git a/crypto/openssh/ssh-keysign.c b/crypto/openssh/ssh-keysign.c index 6bde8ad..1dca3e2 100644 --- a/crypto/openssh/ssh-keysign.c +++ b/crypto/openssh/ssh-keysign.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh-keysign.c,v 1.39 2013/12/06 13:39:49 markus Exp $ */ +/* $OpenBSD: ssh-keysign.c,v 1.49 2015/07/03 03:56:25 djm Exp $ */ /* * Copyright (c) 2002 Markus Friedl. All rights reserved. * @@ -35,23 +35,29 @@ #include <string.h> #include <unistd.h> +#ifdef WITH_OPENSSL #include <openssl/evp.h> #include <openssl/rand.h> #include <openssl/rsa.h> +#endif #include "xmalloc.h" #include "log.h" -#include "key.h" +#include "sshkey.h" #include "ssh.h" #include "ssh2.h" #include "misc.h" -#include "buffer.h" +#include "sshbuf.h" #include "authfile.h" #include "msg.h" #include "canohost.h" #include "pathnames.h" #include "readconf.h" #include "uidswap.h" +#include "sshkey.h" +#include "ssherr.h" + +struct ssh *active_state = NULL; /* XXX needed for linking */ /* XXX readconf.c needs these */ uid_t original_real_uid; @@ -59,62 +65,73 @@ uid_t original_real_uid; extern char *__progname; static int -valid_request(struct passwd *pw, char *host, Key **ret, u_char *data, - u_int datalen) +valid_request(struct passwd *pw, char *host, struct sshkey **ret, + u_char *data, size_t datalen) { - Buffer b; - Key *key = NULL; - u_char *pkblob; - u_int blen, len; - char *pkalg, *p; - int pktype, fail; - + struct sshbuf *b; + struct sshkey *key = NULL; + u_char type, *pkblob; + char *p; + size_t blen, len; + char *pkalg, *luser; + int r, pktype, fail; + + if (ret != NULL) + *ret = NULL; fail = 0; - buffer_init(&b); - buffer_append(&b, data, datalen); + if ((b = sshbuf_from(data, datalen)) == NULL) + fatal("%s: sshbuf_from failed", __func__); /* session id, currently limited to SHA1 (20 bytes) or SHA256 (32) */ - p = buffer_get_string(&b, &len); + if ((r = sshbuf_get_string(b, NULL, &len)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); if (len != 20 && len != 32) fail++; - free(p); - if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST) + if ((r = sshbuf_get_u8(b, &type)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); + if (type != SSH2_MSG_USERAUTH_REQUEST) fail++; /* server user */ - buffer_skip_string(&b); + if ((r = sshbuf_skip_string(b)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); /* service */ - p = buffer_get_string(&b, NULL); + if ((r = sshbuf_get_cstring(b, &p, NULL)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); if (strcmp("ssh-connection", p) != 0) fail++; free(p); /* method */ - p = buffer_get_string(&b, NULL); + if ((r = sshbuf_get_cstring(b, &p, NULL)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); if (strcmp("hostbased", p) != 0) fail++; free(p); /* pubkey */ - pkalg = buffer_get_string(&b, NULL); - pkblob = buffer_get_string(&b, &blen); + if ((r = sshbuf_get_cstring(b, &pkalg, NULL)) != 0 || + (r = sshbuf_get_string(b, &pkblob, &blen)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); - pktype = key_type_from_name(pkalg); + pktype = sshkey_type_from_name(pkalg); if (pktype == KEY_UNSPEC) fail++; - else if ((key = key_from_blob(pkblob, blen)) == NULL) + else if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) { + error("%s: bad key blob: %s", __func__, ssh_err(r)); fail++; - else if (key->type != pktype) + } else if (key->type != pktype) fail++; free(pkalg); free(pkblob); /* client host name, handle trailing dot */ - p = buffer_get_string(&b, &len); - debug2("valid_request: check expect chost %s got %s", host, p); + if ((r = sshbuf_get_cstring(b, &p, &len)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); + debug2("%s: check expect chost %s got %s", __func__, host, p); if (strlen(host) != len - 1) fail++; else if (p[len - 1] != '.') @@ -124,22 +141,23 @@ valid_request(struct passwd *pw, char *host, Key **ret, u_char *data, free(p); /* local user */ - p = buffer_get_string(&b, NULL); + if ((r = sshbuf_get_cstring(b, &luser, NULL)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); - if (strcmp(pw->pw_name, p) != 0) + if (strcmp(pw->pw_name, luser) != 0) fail++; - free(p); + free(luser); /* end of message */ - if (buffer_len(&b) != 0) + if (sshbuf_len(b) != 0) fail++; - buffer_free(&b); + sshbuf_free(b); - debug3("valid_request: fail %d", fail); + debug3("%s: fail %d", __func__, fail); if (fail && key != NULL) - key_free(key); - else + sshkey_free(key); + else if (ret != NULL) *ret = key; return (fail ? -1 : 0); @@ -148,16 +166,18 @@ valid_request(struct passwd *pw, char *host, Key **ret, u_char *data, int main(int argc, char **argv) { - Buffer b; + struct sshbuf *b; Options options; #define NUM_KEYTYPES 4 - Key *keys[NUM_KEYTYPES], *key = NULL; + struct sshkey *keys[NUM_KEYTYPES], *key = NULL; struct passwd *pw; - int key_fd[NUM_KEYTYPES], i, found, version = 2, fd; - u_char *signature, *data; - char *host; - u_int slen, dlen; + int r, key_fd[NUM_KEYTYPES], i, found, version = 2, fd; + u_char *signature, *data, rver; + char *host, *fp; + size_t slen, dlen; +#ifdef WITH_OPENSSL u_int32_t rnd[256]; +#endif /* Ensure that stdin and stdout are connected */ if ((fd = open(_PATH_DEVNULL, O_RDWR)) < 2) @@ -167,6 +187,7 @@ main(int argc, char **argv) close(fd); i = 0; + /* XXX This really needs to read sshd_config for the paths */ key_fd[i++] = open(_PATH_HOST_DSA_KEY_FILE, O_RDONLY); key_fd[i++] = open(_PATH_HOST_ECDSA_KEY_FILE, O_RDONLY); key_fd[i++] = open(_PATH_HOST_ED25519_KEY_FILE, O_RDONLY); @@ -187,7 +208,7 @@ main(int argc, char **argv) /* verify that ssh-keysign is enabled by the admin */ initialize_options(&options); - (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, "", &options, 0); + (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, "", "", &options, 0); fill_default_options(&options); if (options.enable_ssh_keysign != 1) fatal("ssh-keysign not enabled in %s", @@ -200,37 +221,47 @@ main(int argc, char **argv) if (found == 0) fatal("could not open any host key"); +#ifdef WITH_OPENSSL OpenSSL_add_all_algorithms(); - for (i = 0; i < 256; i++) - rnd[i] = arc4random(); + arc4random_buf(rnd, sizeof(rnd)); RAND_seed(rnd, sizeof(rnd)); +#endif found = 0; for (i = 0; i < NUM_KEYTYPES; i++) { keys[i] = NULL; if (key_fd[i] == -1) continue; - keys[i] = key_load_private_pem(key_fd[i], KEY_UNSPEC, - NULL, NULL); + r = sshkey_load_private_type_fd(key_fd[i], KEY_UNSPEC, + NULL, &key, NULL); close(key_fd[i]); - if (keys[i] != NULL) + if (r != 0) + debug("parse key %d: %s", i, ssh_err(r)); + else if (key != NULL) { + keys[i] = key; found = 1; + } } if (!found) fatal("no hostkey found"); - buffer_init(&b); - if (ssh_msg_recv(STDIN_FILENO, &b) < 0) + if ((b = sshbuf_new()) == NULL) + fatal("%s: sshbuf_new failed", __func__); + if (ssh_msg_recv(STDIN_FILENO, b) < 0) fatal("ssh_msg_recv failed"); - if (buffer_get_char(&b) != version) - fatal("bad version"); - fd = buffer_get_int(&b); - if ((fd == STDIN_FILENO) || (fd == STDOUT_FILENO)) + if ((r = sshbuf_get_u8(b, &rver)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); + if (rver != version) + fatal("bad version: received %d, expected %d", rver, version); + if ((r = sshbuf_get_u32(b, (u_int *)&fd)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); + if (fd < 0 || fd == STDIN_FILENO || fd == STDOUT_FILENO) fatal("bad fd"); if ((host = get_local_name(fd)) == NULL) fatal("cannot get local name for fd"); - data = buffer_get_string(&b, &dlen); + if ((r = sshbuf_get_string(b, &data, &dlen)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); if (valid_request(pw, host, &key, data, dlen) < 0) fatal("not a valid request"); free(host); @@ -238,22 +269,28 @@ main(int argc, char **argv) found = 0; for (i = 0; i < NUM_KEYTYPES; i++) { if (keys[i] != NULL && - key_equal_public(key, keys[i])) { + sshkey_equal_public(key, keys[i])) { found = 1; break; } } - if (!found) - fatal("no matching hostkey found"); + if (!found) { + if ((fp = sshkey_fingerprint(key, options.fingerprint_hash, + SSH_FP_DEFAULT)) == NULL) + fatal("%s: sshkey_fingerprint failed", __func__); + fatal("no matching hostkey found for key %s %s", + sshkey_type(key), fp ? fp : ""); + } - if (key_sign(keys[i], &signature, &slen, data, dlen) != 0) - fatal("key_sign failed"); + if ((r = sshkey_sign(keys[i], &signature, &slen, data, dlen, 0)) != 0) + fatal("sshkey_sign failed: %s", ssh_err(r)); free(data); /* send reply */ - buffer_clear(&b); - buffer_put_string(&b, signature, slen); - if (ssh_msg_send(STDOUT_FILENO, version, &b) == -1) + sshbuf_reset(b); + if ((r = sshbuf_put_string(b, signature, slen)) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); + if (ssh_msg_send(STDOUT_FILENO, version, b) == -1) fatal("ssh_msg_send failed"); return (0); |
