X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/7091a26b98ba37110d4ea38c21806484c280b334..802e01b86efac80bfea4b07c6442d8e2c26945f8:/sshconnect2.c diff --git a/sshconnect2.c b/sshconnect2.c index 258d7cf5..0605e4e5 100644 --- a/sshconnect2.c +++ b/sshconnect2.c @@ -23,7 +23,11 @@ */ #include "includes.h" -RCSID("$OpenBSD: sshconnect2.c,v 1.101 2002/05/24 08:45:14 markus Exp $"); +RCSID("$OpenBSD: sshconnect2.c,v 1.118 2003/05/14 02:15:47 markus Exp $"); + +#ifdef KRB5 +#include +#endif #include "ssh.h" #include "ssh2.h" @@ -82,7 +86,7 @@ ssh_kex2(char *host, struct sockaddr *hostaddr) xxx_hostaddr = hostaddr; if (options.ciphers == (char *)-1) { - log("No valid ciphers for protocol version 2 given, using defaults."); + logit("No valid ciphers for protocol version 2 given, using defaults."); options.ciphers = NULL; } if (options.ciphers != NULL) { @@ -95,10 +99,10 @@ ssh_kex2(char *host, struct sockaddr *hostaddr) compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]); if (options.compression) { myproposal[PROPOSAL_COMP_ALGS_CTOS] = - myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib"; + myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib,none"; } else { myproposal[PROPOSAL_COMP_ALGS_CTOS] = - myproposal[PROPOSAL_COMP_ALGS_STOC] = "none"; + myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib"; } if (options.macs != NULL) { myproposal[PROPOSAL_MAC_ALGS_CTOS] = @@ -108,8 +112,13 @@ ssh_kex2(char *host, struct sockaddr *hostaddr) myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = options.hostkeyalgorithms; + if (options.rekey_limit) + packet_set_rekey_limit(options.rekey_limit); + /* start key exchange */ kex = kex_setup(myproposal); + kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client; + kex->kex[KEX_DH_GEX_SHA1] = kexgex_client; kex->client_version_string=client_version_string; kex->server_version_string=server_version_string; kex->verify_host_key=&verify_host_key_callback; @@ -128,7 +137,6 @@ ssh_kex2(char *host, struct sockaddr *hostaddr) packet_send(); packet_write_wait(); #endif - debug("done: ssh_kex2."); } /* @@ -137,10 +145,18 @@ ssh_kex2(char *host, struct sockaddr *hostaddr) typedef struct Authctxt Authctxt; typedef struct Authmethod Authmethod; - -typedef int sign_cb_fn( - Authctxt *authctxt, Key *key, - u_char **sigp, u_int *lenp, u_char *data, u_int datalen); +typedef struct identity Identity; +typedef struct idlist Idlist; + +struct identity { + TAILQ_ENTRY(identity) next; + AuthenticationConnection *ac; /* set if agent supports key */ + Key *key; /* public/private key */ + char *filename; /* comment for agent-only keys */ + int tried; + int isprivate; /* key points to the private key */ +}; +TAILQ_HEAD(idlist, identity); struct Authctxt { const char *server_user; @@ -151,9 +167,7 @@ struct Authctxt { int success; char *authlist; /* pubkey */ - Key *last_key; - sign_cb_fn *last_key_sign; - int last_key_hint; + Idlist keys; AuthenticationConnection *agent; /* hostbased */ Sensitive *sensitive; @@ -180,11 +194,15 @@ int userauth_pubkey(Authctxt *); int userauth_passwd(Authctxt *); int userauth_kbdint(Authctxt *); int userauth_hostbased(Authctxt *); +int userauth_kerberos(Authctxt *); void userauth(Authctxt *, char *); -static int sign_and_send_pubkey(Authctxt *, Key *, sign_cb_fn *); +static int sign_and_send_pubkey(Authctxt *, Identity *); static void clear_auth_state(Authctxt *); +static void pubkey_prepare(Authctxt *); +static void pubkey_cleanup(Authctxt *); +static Key *load_identity_file(char *); static Authmethod *authmethod_get(char *authlist); static Authmethod *authmethod_lookup(const char *name); @@ -195,6 +213,12 @@ Authmethod authmethods[] = { userauth_hostbased, &options.hostbased_authentication, NULL}, +#if KRB5 + {"kerberos-2@ssh.com", + userauth_kerberos, + &options.kerberos_authentication, + NULL}, +#endif {"publickey", userauth_pubkey, &options.pubkey_authentication, @@ -224,31 +248,30 @@ ssh_userauth2(const char *local_user, const char *server_user, char *host, if (options.challenge_response_authentication) options.kbd_interactive_authentication = 1; - debug("send SSH2_MSG_SERVICE_REQUEST"); packet_start(SSH2_MSG_SERVICE_REQUEST); packet_put_cstring("ssh-userauth"); packet_send(); + debug("SSH2_MSG_SERVICE_REQUEST sent"); packet_write_wait(); type = packet_read(); - if (type != SSH2_MSG_SERVICE_ACCEPT) { - fatal("denied SSH2_MSG_SERVICE_ACCEPT: %d", type); - } + if (type != SSH2_MSG_SERVICE_ACCEPT) + fatal("Server denied authentication request: %d", type); if (packet_remaining() > 0) { char *reply = packet_get_string(NULL); - debug("service_accept: %s", reply); + debug2("service_accept: %s", reply); xfree(reply); } else { - debug("buggy server: service_accept w/o service"); + debug2("buggy server: service_accept w/o service"); } packet_check_eom(); - debug("got SSH2_MSG_SERVICE_ACCEPT"); + debug("SSH2_MSG_SERVICE_ACCEPT received"); if (options.preferred_authentications == NULL) options.preferred_authentications = authmethods_get(); /* setup authentication context */ memset(&authctxt, 0, sizeof(authctxt)); - authctxt.agent = ssh_get_authentication_connection(); + pubkey_prepare(&authctxt); authctxt.server_user = server_user; authctxt.local_user = local_user; authctxt.host = host; @@ -270,10 +293,8 @@ ssh_userauth2(const char *local_user, const char *server_user, char *host, dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner); dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */ - if (authctxt.agent != NULL) - ssh_close_authentication_connection(authctxt.agent); - - debug("ssh-userauth2 successful: method %s", authctxt.method->name); + pubkey_cleanup(&authctxt); + debug("Authentication succeeded (%s).", authctxt.method->name); } void userauth(Authctxt *authctxt, char *authlist) @@ -299,12 +320,14 @@ userauth(Authctxt *authctxt, char *authlist) } } } + void input_userauth_error(int type, u_int32_t seq, void *ctxt) { fatal("input_userauth_error: bad message during authentication: " "type %d", type); } + void input_userauth_banner(int type, u_int32_t seq, void *ctxt) { @@ -316,6 +339,7 @@ input_userauth_banner(int type, u_int32_t seq, void *ctxt) xfree(msg); xfree(lang); } + void input_userauth_success(int type, u_int32_t seq, void *ctxt) { @@ -327,6 +351,7 @@ input_userauth_success(int type, u_int32_t seq, void *ctxt) clear_auth_state(authctxt); authctxt->success = 1; /* break out */ } + void input_userauth_failure(int type, u_int32_t seq, void *ctxt) { @@ -342,8 +367,8 @@ input_userauth_failure(int type, u_int32_t seq, void *ctxt) packet_check_eom(); if (partial != 0) - log("Authenticated with partial success."); - debug("authentications that can continue: %s", authlist); + logit("Authenticated with partial success."); + debug("Authentications that can continue: %s", authlist); clear_auth_state(authctxt); userauth(authctxt, authlist); @@ -353,6 +378,7 @@ input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt) { Authctxt *authctxt = ctxt; Key *key = NULL; + Identity *id = NULL; Buffer b; int pktype, sent = 0; u_int alen, blen; @@ -375,40 +401,33 @@ input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt) } packet_check_eom(); - debug("input_userauth_pk_ok: pkalg %s blen %d lastkey %p hint %d", - pkalg, blen, authctxt->last_key, authctxt->last_key_hint); + debug("Server accepts key: pkalg %s blen %u", pkalg, blen); - do { - if (authctxt->last_key == NULL || - authctxt->last_key_sign == NULL) { - debug("no last key or no sign cb"); - break; - } - if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) { - debug("unknown pkalg %s", pkalg); - break; - } - if ((key = key_from_blob(pkblob, blen)) == NULL) { - debug("no key from blob. pkalg %s", pkalg); - break; - } - if (key->type != pktype) { - error("input_userauth_pk_ok: type mismatch " - "for decoded key (received %d, expected %d)", - key->type, pktype); - break; - } - fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX); - debug2("input_userauth_pk_ok: fp %s", fp); - xfree(fp); - if (!key_equal(key, authctxt->last_key)) { - debug("key != last_key"); + if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) { + debug("unknown pkalg %s", pkalg); + goto done; + } + if ((key = key_from_blob(pkblob, blen)) == NULL) { + debug("no key from blob. pkalg %s", pkalg); + goto done; + } + if (key->type != pktype) { + error("input_userauth_pk_ok: type mismatch " + "for decoded key (received %d, expected %d)", + key->type, pktype); + goto done; + } + fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX); + debug2("input_userauth_pk_ok: fp %s", fp); + xfree(fp); + + TAILQ_FOREACH(id, &authctxt->keys, next) { + if (key_equal(key, id->key)) { + sent = sign_and_send_pubkey(authctxt, id); break; } - sent = sign_and_send_pubkey(authctxt, key, - authctxt->last_key_sign); - } while (0); - + } +done: if (key != NULL) key_free(key); xfree(pkalg); @@ -418,10 +437,9 @@ input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt) clear_auth_state(authctxt); dispatch_set(SSH2_MSG_USERAUTH_PK_OK, NULL); - /* try another method if we did not send a packet*/ + /* try another method if we did not send a packet */ if (sent == 0) userauth(authctxt, NULL); - } int @@ -463,7 +481,7 @@ userauth_passwd(Authctxt *authctxt) packet_add_padding(64); packet_send(); - dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, + dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, &input_userauth_passwd_changereq); return 1; @@ -487,7 +505,7 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt) info = packet_get_string(NULL); lang = packet_get_string(NULL); if (strlen(info) > 0) - log("%s", info); + logit("%s", info); xfree(info); xfree(lang); packet_start(SSH2_MSG_USERAUTH_REQUEST); @@ -495,7 +513,7 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt) packet_put_cstring(authctxt->service); packet_put_cstring(authctxt->method->name); packet_put_char(1); /* additional info */ - snprintf(prompt, sizeof(prompt), + snprintf(prompt, sizeof(prompt), "Enter %.30s@%.128s's old password: ", authctxt->server_user, authctxt->host); password = read_passphrase(prompt, 0); @@ -504,7 +522,7 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt) xfree(password); password = NULL; while (password == NULL) { - snprintf(prompt, sizeof(prompt), + snprintf(prompt, sizeof(prompt), "Enter %.30s@%.128s's new password: ", authctxt->server_user, authctxt->host); password = read_passphrase(prompt, RP_ALLOW_EOF); @@ -512,14 +530,14 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt) /* bail out */ return; } - snprintf(prompt, sizeof(prompt), + snprintf(prompt, sizeof(prompt), "Retype %.30s@%.128s's new password: ", authctxt->server_user, authctxt->host); retype = read_passphrase(prompt, 0); if (strcmp(password, retype) != 0) { memset(password, 0, strlen(password)); xfree(password); - log("Mismatch; try again, EOF to quit."); + logit("Mismatch; try again, EOF to quit."); password = NULL; } memset(retype, 0, strlen(retype)); @@ -530,8 +548,8 @@ input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt) xfree(password); packet_add_padding(64); packet_send(); - - dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, + + dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, &input_userauth_passwd_changereq); } @@ -540,18 +558,35 @@ clear_auth_state(Authctxt *authctxt) { /* XXX clear authentication state */ dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, NULL); +} - if (authctxt->last_key != NULL && authctxt->last_key_hint == -1) { - debug3("clear_auth_state: key_free %p", authctxt->last_key); - key_free(authctxt->last_key); - } - authctxt->last_key = NULL; - authctxt->last_key_hint = -2; - authctxt->last_key_sign = NULL; +static int +identity_sign(Identity *id, u_char **sigp, u_int *lenp, + u_char *data, u_int datalen) +{ + Key *prv; + int ret; + + /* the agent supports this key */ + if (id->ac) + return (ssh_agent_sign(id->ac, id->key, sigp, lenp, + data, datalen)); + /* + * we have already loaded the private key or + * the private key is stored in external hardware + */ + if (id->isprivate || (id->key->flags & KEY_FLAG_EXT)) + return (key_sign(id->key, sigp, lenp, data, datalen)); + /* load the private key from the file */ + if ((prv = load_identity_file(id->filename)) == NULL) + return (-1); + ret = key_sign(prv, sigp, lenp, data, datalen); + key_free(prv); + return (ret); } static int -sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback) +sign_and_send_pubkey(Authctxt *authctxt, Identity *id) { Buffer b; u_char *blob, *signature; @@ -562,7 +597,7 @@ sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback) debug3("sign_and_send_pubkey"); - if (key_to_blob(k, &blob, &bloblen) == 0) { + if (key_to_blob(id->key, &blob, &bloblen) == 0) { /* we cannot handle this key */ debug3("sign_and_send_pubkey: cannot handle key"); return 0; @@ -587,12 +622,12 @@ sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback) } else { buffer_put_cstring(&b, authctxt->method->name); buffer_put_char(&b, have_sig); - buffer_put_cstring(&b, key_ssh_name(k)); + buffer_put_cstring(&b, key_ssh_name(id->key)); } buffer_put_string(&b, blob, bloblen); /* generate signature */ - ret = (*sign_callback)(authctxt, k, &signature, &slen, + ret = identity_sign(id, &signature, &slen, buffer_ptr(&b), buffer_len(&b)); if (ret == -1) { xfree(blob); @@ -612,7 +647,7 @@ sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback) buffer_put_cstring(&b, authctxt->method->name); buffer_put_char(&b, have_sig); if (!(datafellows & SSH_BUG_PKAUTH)) - buffer_put_cstring(&b, key_ssh_name(k)); + buffer_put_cstring(&b, key_ssh_name(id->key)); buffer_put_string(&b, blob, bloblen); } xfree(blob); @@ -636,23 +671,19 @@ sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback) } static int -send_pubkey_test(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback, - int hint) +send_pubkey_test(Authctxt *authctxt, Identity *id) { u_char *blob; u_int bloblen, have_sig = 0; debug3("send_pubkey_test"); - if (key_to_blob(k, &blob, &bloblen) == 0) { + if (key_to_blob(id->key, &blob, &bloblen) == 0) { /* we cannot handle this key */ debug3("send_pubkey_test: cannot handle key"); return 0; } /* register callback for USERAUTH_PK_OK message */ - authctxt->last_key_sign = sign_callback; - authctxt->last_key_hint = hint; - authctxt->last_key = k; dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok); packet_start(SSH2_MSG_USERAUTH_REQUEST); @@ -661,7 +692,7 @@ send_pubkey_test(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback, packet_put_cstring(authctxt->method->name); packet_put_char(have_sig); if (!(datafellows & SSH_BUG_PKAUTH)) - packet_put_cstring(key_ssh_name(k)); + packet_put_cstring(key_ssh_name(id->key)); packet_put_string(blob, bloblen); xfree(blob); packet_send(); @@ -706,103 +737,134 @@ load_identity_file(char *filename) return private; } -static int -identity_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp, - u_char *data, u_int datalen) -{ - Key *private; - int idx, ret; - - idx = authctxt->last_key_hint; - if (idx < 0) - return -1; - - /* private key is stored in external hardware */ - if (options.identity_keys[idx]->flags & KEY_FLAG_EXT) - return key_sign(options.identity_keys[idx], sigp, lenp, data, datalen); - - private = load_identity_file(options.identity_files[idx]); - if (private == NULL) - return -1; - ret = key_sign(private, sigp, lenp, data, datalen); - key_free(private); - return ret; -} - -static int -agent_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp, - u_char *data, u_int datalen) -{ - return ssh_agent_sign(authctxt->agent, key, sigp, lenp, data, datalen); -} - -static int -key_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, u_int *lenp, - u_char *data, u_int datalen) +/* + * try keys in the following order: + * 1. agent keys that are found in the config file + * 2. other agent keys + * 3. keys that are only listed in the config file + */ +static void +pubkey_prepare(Authctxt *authctxt) { - return key_sign(key, sigp, lenp, data, datalen); + Identity *id; + Idlist agent, files, *preferred; + Key *key; + AuthenticationConnection *ac; + char *comment; + int i, found; + + TAILQ_INIT(&agent); /* keys from the agent */ + TAILQ_INIT(&files); /* keys from the config file */ + preferred = &authctxt->keys; + TAILQ_INIT(preferred); /* preferred order of keys */ + + /* list of keys stored in the filesystem */ + for (i = 0; i < options.num_identity_files; i++) { + key = options.identity_keys[i]; + if (key && key->type == KEY_RSA1) + continue; + options.identity_keys[i] = NULL; + id = xmalloc(sizeof(*id)); + memset(id, 0, sizeof(*id)); + id->key = key; + id->filename = xstrdup(options.identity_files[i]); + TAILQ_INSERT_TAIL(&files, id, next); + } + /* list of keys supported by the agent */ + if ((ac = ssh_get_authentication_connection())) { + for (key = ssh_get_first_identity(ac, &comment, 2); + key != NULL; + key = ssh_get_next_identity(ac, &comment, 2)) { + found = 0; + TAILQ_FOREACH(id, &files, next) { + /* agent keys from the config file are preferred */ + if (key_equal(key, id->key)) { + key_free(key); + xfree(comment); + TAILQ_REMOVE(&files, id, next); + TAILQ_INSERT_TAIL(preferred, id, next); + id->ac = ac; + found = 1; + break; + } + } + if (!found) { + id = xmalloc(sizeof(*id)); + memset(id, 0, sizeof(*id)); + id->key = key; + id->filename = comment; + id->ac = ac; + TAILQ_INSERT_TAIL(&agent, id, next); + } + } + /* append remaining agent keys */ + for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) { + TAILQ_REMOVE(&agent, id, next); + TAILQ_INSERT_TAIL(preferred, id, next); + } + authctxt->agent = ac; + } + /* append remaining keys from the config file */ + for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) { + TAILQ_REMOVE(&files, id, next); + TAILQ_INSERT_TAIL(preferred, id, next); + } + TAILQ_FOREACH(id, preferred, next) { + debug2("key: %s (%p)", id->filename, id->key); + } } -static int -userauth_pubkey_agent(Authctxt *authctxt) +static void +pubkey_cleanup(Authctxt *authctxt) { - static int called = 0; - int ret = 0; - char *comment; - Key *k; - - if (called == 0) { - if (ssh_get_num_identities(authctxt->agent, 2) == 0) - debug2("userauth_pubkey_agent: no keys at all"); - called = 1; + Identity *id; + + if (authctxt->agent != NULL) + ssh_close_authentication_connection(authctxt->agent); + for (id = TAILQ_FIRST(&authctxt->keys); id; + id = TAILQ_FIRST(&authctxt->keys)) { + TAILQ_REMOVE(&authctxt->keys, id, next); + if (id->key) + key_free(id->key); + if (id->filename) + xfree(id->filename); + xfree(id); } - k = ssh_get_next_identity(authctxt->agent, &comment, 2); - if (k == NULL) { - debug2("userauth_pubkey_agent: no more keys"); - } else { - debug("userauth_pubkey_agent: testing agent key %s", comment); - xfree(comment); - ret = send_pubkey_test(authctxt, k, agent_sign_cb, -1); - if (ret == 0) - key_free(k); - } - if (ret == 0) - debug2("userauth_pubkey_agent: no message sent"); - return ret; } int userauth_pubkey(Authctxt *authctxt) { - static int idx = 0; + Identity *id; int sent = 0; - Key *key; - char *filename; - if (authctxt->agent != NULL) { - do { - sent = userauth_pubkey_agent(authctxt); - } while (!sent && authctxt->agent->howmany > 0); - } - while (!sent && idx < options.num_identity_files) { - key = options.identity_keys[idx]; - filename = options.identity_files[idx]; - if (key == NULL) { - debug("try privkey: %s", filename); - key = load_identity_file(filename); - if (key != NULL) { - sent = sign_and_send_pubkey(authctxt, key, - key_sign_cb); - key_free(key); + while ((id = TAILQ_FIRST(&authctxt->keys))) { + if (id->tried++) + return (0); + TAILQ_REMOVE(&authctxt->keys, id, next); + TAILQ_INSERT_TAIL(&authctxt->keys, id, next); + /* + * send a test message if we have the public key. for + * encrypted keys we cannot do this and have to load the + * private key instead + */ + if (id->key && id->key->type != KEY_RSA1) { + debug("Offering public key: %s", id->filename); + sent = send_pubkey_test(authctxt, id); + } else if (id->key == NULL) { + debug("Trying private key: %s", id->filename); + id->key = load_identity_file(id->filename); + if (id->key != NULL) { + id->isprivate = 1; + sent = sign_and_send_pubkey(authctxt, id); + key_free(id->key); + id->key = NULL; } - } else if (key->type != KEY_RSA1) { - debug("try pubkey: %s", filename); - sent = send_pubkey_test(authctxt, key, - identity_sign_cb, idx); } - idx++; + if (sent) + return (sent); } - return sent; + return (0); } /* @@ -858,9 +920,9 @@ input_userauth_info_req(int type, u_int32_t seq, void *ctxt) inst = packet_get_string(NULL); lang = packet_get_string(NULL); if (strlen(name) > 0) - log("%s", name); + logit("%s", name); if (strlen(inst) > 0) - log("%s", inst); + logit("%s", inst); xfree(name); xfree(inst); xfree(lang); @@ -894,17 +956,15 @@ input_userauth_info_req(int type, u_int32_t seq, void *ctxt) } static int -ssh_keysign( - Key *key, - u_char **sigp, u_int *lenp, +ssh_keysign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen) { Buffer b; struct stat st; pid_t pid; - int to[2], from[2], status, version = 1; + int to[2], from[2], status, version = 2; - debug("ssh_keysign called"); + debug2("ssh_keysign called"); if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) { error("ssh_keysign: no installed: %s", strerror(errno)); @@ -933,7 +993,9 @@ ssh_keysign( close(to[1]); if (dup2(to[0], STDIN_FILENO) < 0) fatal("ssh_keysign: dup2: %s", strerror(errno)); - execlp(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0); + close(from[1]); + close(to[0]); + execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0); fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN, strerror(errno)); } @@ -941,10 +1003,11 @@ ssh_keysign( close(to[0]); buffer_init(&b); + buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */ buffer_put_string(&b, data, datalen); - msg_send(to[1], version, &b); + ssh_msg_send(to[1], version, &b); - if (msg_recv(from[0], &b) < 0) { + if (ssh_msg_recv(from[0], &b) < 0) { error("ssh_keysign: no reply"); buffer_clear(&b); return -1; @@ -952,9 +1015,9 @@ ssh_keysign( close(from[0]); close(to[1]); - while (waitpid(pid, &status, 0) < 0) - if (errno != EINTR) - break; + while (waitpid(pid, &status, 0) < 0) + if (errno != EINTR) + break; if (buffer_get_char(&b) != version) { error("ssh_keysign: bad version"); @@ -990,7 +1053,7 @@ userauth_hostbased(Authctxt *authctxt) } } if (!found) { - debug("userauth_hostbased: no more client hostkeys"); + debug("No more client hostkeys for hostbased authentication."); return 0; } if (key_to_blob(private, &blob, &blen) == 0) { @@ -1009,6 +1072,7 @@ userauth_hostbased(Authctxt *authctxt) strlcpy(chost, p, len); strlcat(chost, ".", len); debug2("userauth_hostbased: chost %s", chost); + xfree(p); service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" : authctxt->service; @@ -1059,6 +1123,94 @@ userauth_hostbased(Authctxt *authctxt) return 1; } +#if KRB5 +static int +ssh_krb5_helper(krb5_data *ap) +{ + krb5_context xcontext = NULL; /* XXX share with ssh1 */ + krb5_auth_context xauth_context = NULL; + + krb5_context *context; + krb5_auth_context *auth_context; + krb5_error_code problem; + const char *tkfile; + struct stat buf; + krb5_ccache ccache = NULL; + const char *remotehost; + int ret; + + memset(ap, 0, sizeof(*ap)); + + context = &xcontext; + auth_context = &xauth_context; + + problem = krb5_init_context(context); + if (problem) { + debug("Kerberos v5: krb5_init_context failed"); + ret = 0; + goto out; + } + + tkfile = krb5_cc_default_name(*context); + if (strncmp(tkfile, "FILE:", 5) == 0) + tkfile += 5; + + if (stat(tkfile, &buf) == 0 && getuid() != buf.st_uid) { + debug("Kerberos v5: could not get default ccache (permission denied)."); + ret = 0; + goto out; + } + + problem = krb5_cc_default(*context, &ccache); + if (problem) { + debug("Kerberos v5: krb5_cc_default failed: %s", + krb5_get_err_text(*context, problem)); + ret = 0; + goto out; + } + + remotehost = get_canonical_hostname(1); + + problem = krb5_mk_req(*context, auth_context, AP_OPTS_MUTUAL_REQUIRED, + "host", remotehost, NULL, ccache, ap); + if (problem) { + debug("Kerberos v5: krb5_mk_req failed: %s", + krb5_get_err_text(*context, problem)); + ret = 0; + goto out; + } + ret = 1; + + out: + if (ccache != NULL) + krb5_cc_close(*context, ccache); + if (*auth_context) + krb5_auth_con_free(*context, *auth_context); + if (*context) + krb5_free_context(*context); + return (ret); +} + +int +userauth_kerberos(Authctxt *authctxt) +{ + krb5_data ap; + + if (ssh_krb5_helper(&ap) == 0) + return (0); + + packet_start(SSH2_MSG_USERAUTH_REQUEST); + packet_put_cstring(authctxt->server_user); + packet_put_cstring(authctxt->service); + packet_put_cstring(authctxt->method->name); + packet_put_string(ap.data, ap.length); + packet_send(); + + krb5_data_free(&ap); + return (1); +} +#endif + /* find auth method */ /* @@ -1095,6 +1247,7 @@ authmethod_lookup(const char *name) static Authmethod *current = NULL; static char *supported = NULL; static char *preferred = NULL; + /* * Given the authentication method list sent by the server, return the * next method we should try. If the server initially sends a nil list, @@ -1103,7 +1256,6 @@ static char *preferred = NULL; static Authmethod * authmethod_get(char *authlist) { - char *name = NULL; u_int next; @@ -1124,7 +1276,7 @@ authmethod_get(char *authlist) for (;;) { if ((name = match_list(preferred, supported, &next)) == NULL) { - debug("no more auth methods to try"); + debug("No more authentication methods to try."); current = NULL; return NULL; } @@ -1134,7 +1286,7 @@ authmethod_get(char *authlist) if ((current = authmethod_lookup(name)) != NULL && authmethod_is_enabled(current)) { debug3("authmethod_is_enabled %s", name); - debug("next auth method to try is %s", name); + debug("Next authentication method: %s", name); return current; } }