int sftp_auth_hostbased(struct ssh2_packet *pkt, cmd_rec *pass_cmd, const char *orig_user, const char *user, const char *service, unsigned char **buf, uint32_t *buflen, int *send_userauth_fail) { struct passwd *pw; char *hostkey_algo, *host_fqdn, *host_user, *host_user_utf8; const char *fp = NULL; unsigned char *hostkey_data, *signature_data; unsigned char *buf2, *ptr2; const unsigned char *id; uint32_t buflen2, bufsz2, hostkey_datalen, id_len, signature_len; enum sftp_key_type_e pubkey_type; if (pr_cmd_dispatch_phase(pass_cmd, PRE_CMD, 0) < 0) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "authentication request for user '%s' blocked by '%s' handler", orig_user, (char *) pass_cmd->argv[0]); pr_cmd_dispatch_phase(pass_cmd, POST_CMD_ERR, 0); pr_cmd_dispatch_phase(pass_cmd, LOG_CMD_ERR, 0); *send_userauth_fail = TRUE; errno = EPERM; return 0; } hostkey_algo = sftp_msg_read_string(pkt->pool, buf, buflen); if (hostkey_algo == NULL) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "missing required host key algorithm, rejecting request"); *send_userauth_fail = TRUE; errno = EINVAL; return 0; } hostkey_datalen = sftp_msg_read_int(pkt->pool, buf, buflen); hostkey_data = sftp_msg_read_data(pkt->pool, buf, buflen, hostkey_datalen); host_fqdn = sftp_msg_read_string(pkt->pool, buf, buflen); host_user_utf8 = sftp_msg_read_string(pkt->pool, buf, buflen); host_user = sftp_utf8_decode_str(pkt->pool, host_user_utf8); signature_len = sftp_msg_read_int(pkt->pool, buf, buflen); signature_data = sftp_msg_read_data(pkt->pool, buf, buflen, signature_len); pr_trace_msg(trace_channel, 9, "client sent '%s' host key, FQDN %s, and remote user '%s'", hostkey_algo, host_fqdn, host_user); if (strncmp(hostkey_algo, "ssh-rsa", 8) == 0) { pubkey_type = SFTP_KEY_RSA; } else if (strncmp(hostkey_algo, "ssh-dss", 8) == 0) { pubkey_type = SFTP_KEY_DSA; #ifdef PR_USE_OPENSSL_ECC } else if (strncmp(hostkey_algo, "ecdsa-sha2-nistp256", 20) == 0) { pubkey_type = SFTP_KEY_ECDSA_256; } else if (strncmp(hostkey_algo, "ecdsa-sha2-nistp256", 20) == 0) { pubkey_type = SFTP_KEY_ECDSA_384; } else if (strncmp(hostkey_algo, "ecdsa-sha2-nistp256", 20) == 0) { pubkey_type = SFTP_KEY_ECDSA_521; #endif /* PR_USE_OPENSSL_ECC */ /* XXX Need to support X509v3 certs here */ } else { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "unsupported host key algorithm '%s' requested, rejecting request", hostkey_algo); *send_userauth_fail = TRUE; errno = EINVAL; return 0; } if (sftp_keys_verify_pubkey_type(pkt->pool, hostkey_data, hostkey_datalen, pubkey_type) != TRUE) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "unable to verify that given host key matches given '%s' algorithm", hostkey_algo); *send_userauth_fail = TRUE; errno = EINVAL; return 0; } #ifdef OPENSSL_FIPS if (FIPS_mode()) { fp = sftp_keys_get_fingerprint(pkt->pool, hostkey_data, hostkey_datalen, SFTP_KEYS_FP_DIGEST_SHA1); if (fp != NULL) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "public key SHA1 fingerprint: %s", fp); } else { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "error obtaining public key SHA1 fingerprint: %s", strerror(errno)); } } else { #endif /* OPENSSL_FIPS */ fp = sftp_keys_get_fingerprint(pkt->pool, hostkey_data, hostkey_datalen, SFTP_KEYS_FP_DIGEST_MD5); if (fp != NULL) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "public key MD5 fingerprint: %s", fp); } else { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "error obtaining public key MD5 fingerprint: %s", strerror(errno)); } #ifdef OPENSSL_FIPS } #endif /* OPENSSL_FIPS */ pw = pr_auth_getpwnam(pkt->pool, user); if (pw == NULL) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "no account for user '%s' found", user); pr_log_auth(PR_LOG_NOTICE, "USER %s: no such user found from %s [%s] to %s:%d", user, session.c->remote_name, pr_netaddr_get_ipstr(session.c->remote_addr), pr_netaddr_get_ipstr(session.c->local_addr), session.c->local_port); *send_userauth_fail = TRUE; errno = ENOENT; return 0; } /* XXX Should we check the given FQDN here against the client's actual * DNS name and/or IP address? Or leave that up to the keystore's * verify_host_key() function? */ if (sftp_blacklist_reject_key(pkt->pool, hostkey_data, hostkey_datalen)) { *send_userauth_fail = TRUE; errno = EACCES; return 0; } /* The client signed the request as well; we need to authenticate the * host with the given key now. If that succeeds, we use the signature to * verify the request. And if that succeeds, then we're done authenticating. */ if (sftp_keystore_verify_host_key(pkt->pool, user, host_fqdn, host_user, hostkey_data, hostkey_datalen) < 0) { *send_userauth_fail = TRUE; errno = EACCES; return 0; } /* Make sure the signature matches as well. */ id_len = sftp_session_get_id(&id); /* XXX Is this buffer large enough? Too large? */ bufsz2 = buflen2 = 2048; ptr2 = buf2 = sftp_msg_getbuf(pkt->pool, bufsz2); sftp_msg_write_data(&buf2, &buflen2, id, id_len, TRUE); sftp_msg_write_byte(&buf2, &buflen2, SFTP_SSH2_MSG_USER_AUTH_REQUEST); sftp_msg_write_string(&buf2, &buflen2, orig_user); if (sftp_interop_supports_feature(SFTP_SSH2_FEAT_SERVICE_IN_HOST_SIG)) { sftp_msg_write_string(&buf2, &buflen2, service); } else { sftp_msg_write_string(&buf2, &buflen2, "ssh-userauth"); } sftp_msg_write_string(&buf2, &buflen2, "hostbased"); sftp_msg_write_string(&buf2, &buflen2, hostkey_algo); sftp_msg_write_data(&buf2, &buflen2, hostkey_data, hostkey_datalen, TRUE); sftp_msg_write_string(&buf2, &buflen2, host_fqdn); sftp_msg_write_string(&buf2, &buflen2, host_user_utf8); if (sftp_keys_verify_signed_data(pkt->pool, hostkey_algo, hostkey_data, hostkey_datalen, signature_data, signature_len, (unsigned char *) ptr2, (bufsz2 - buflen2)) < 0) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "failed to verify '%s' signature on hostbased auth request for " "user '%s', host %s", hostkey_algo, orig_user, host_fqdn); *send_userauth_fail = TRUE; return 0; } /* Make sure the user is authorized to login. Normally this is checked * as part of the password verification process, but in the case of * hostbased authentication, there is no password to verify. */ if (pr_auth_authorize(pkt->pool, user) != PR_AUTH_OK) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "authentication for user '%s' failed: User not authorized", user); pr_log_auth(PR_LOG_NOTICE, "USER %s (Login failed): User not authorized " "for login", user); *send_userauth_fail = TRUE; errno = EACCES; return 0; } return 1; }
int sftp_kbdint_recv_response(pool *p, unsigned int expected_count, unsigned int *rcvd_count, const char ***responses) { register unsigned int i; unsigned char *buf; cmd_rec *cmd; array_header *list; uint32_t buflen, resp_count; struct ssh2_packet *pkt; char mesg_type; int res; if (p == NULL || rcvd_count == NULL || responses == NULL) { errno = EINVAL; return -1; } pkt = sftp_ssh2_packet_create(kbdint_pool); res = sftp_ssh2_packet_read(sftp_conn->rfd, pkt); if (res < 0) { destroy_pool(pkt->pool); return res; } mesg_type = sftp_ssh2_packet_get_mesg_type(pkt); if (mesg_type != SFTP_SSH2_MSG_USER_AUTH_INFO_RESP) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "expecting USER_AUTH_INFO_RESP message, received %s (%d)", sftp_ssh2_packet_get_mesg_type_desc(mesg_type), mesg_type); destroy_pool(pkt->pool); errno = EPERM; return -1; } cmd = pr_cmd_alloc(pkt->pool, 2, pstrdup(pkt->pool, "USER_AUTH_INFO_RESP")); cmd->arg = "(data)"; pr_trace_msg(trace_channel, 9, "reading USER_AUTH_INFO_RESP message from client"); buf = pkt->payload; buflen = pkt->payload_len; resp_count = sftp_msg_read_int(pkt->pool, &buf, &buflen); /* Ensure that the number of responses sent by the client is the same * as the number of challenges sent, lest a malicious client attempt to * trick us into allocating too much memory (Bug#3973). */ if (resp_count != expected_count) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "sent %lu %s, but received %lu %s", (unsigned long) expected_count, expected_count != 1 ? "challenges" : "challenge", (unsigned long) resp_count, resp_count != 1 ? "responses" : "response"); destroy_pool(pkt->pool); errno = EPERM; return -1; } if (resp_count > SFTP_KBDINT_MAX_RESPONSES) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "received too many responses (%lu > max %lu), rejecting", (unsigned long) resp_count, (unsigned long) SFTP_KBDINT_MAX_RESPONSES); destroy_pool(pkt->pool); errno = EPERM; return -1; } list = make_array(p, resp_count, sizeof(char *)); for (i = 0; i < resp_count; i++) { char *resp; resp = sftp_msg_read_string(pkt->pool, &buf, &buflen); *((char **) push_array(list)) = pstrdup(p, sftp_utf8_decode_str(p, resp)); } *rcvd_count = (unsigned int) resp_count; *responses = ((const char **) list->elts); return 0; }
int sftp_auth_publickey(struct ssh2_packet *pkt, cmd_rec *pass_cmd, const char *orig_user, const char *user, const char *service, char **buf, uint32_t *buflen, int *send_userauth_fail) { int have_signature, pubkey_type; char *pubkey_algo = NULL, *pubkey_data; const char *fp = NULL; uint32_t pubkey_len; struct passwd *pw; if (pr_cmd_dispatch_phase(pass_cmd, PRE_CMD, 0) < 0) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "authentication request for user '%s' blocked by '%s' handler", orig_user, pass_cmd->argv[0]); pr_cmd_dispatch_phase(pass_cmd, POST_CMD_ERR, 0); pr_cmd_dispatch_phase(pass_cmd, LOG_CMD_ERR, 0); *send_userauth_fail = TRUE; errno = EPERM; return 0; } have_signature = sftp_msg_read_bool(pkt->pool, buf, buflen); if (sftp_interop_supports_feature(SFTP_SSH2_FEAT_HAVE_PUBKEY_ALGO)) { pubkey_algo = sftp_msg_read_string(pkt->pool, buf, buflen); } pubkey_len = sftp_msg_read_int(pkt->pool, buf, buflen); pubkey_data = sftp_msg_read_data(pkt->pool, buf, buflen, pubkey_len); if (pubkey_algo == NULL) { /* The client did not send the string identifying the public key algorithm. * Thus we need to extract the algorithm string from the public key data. */ pubkey_algo = sftp_msg_read_string(pkt->pool, &pubkey_data, &pubkey_len); } pr_trace_msg(trace_channel, 9, "client sent '%s' public key %s", pubkey_algo, have_signature ? "with signature" : "without signature"); if (strncmp(pubkey_algo, "ssh-rsa", 8) == 0) { pubkey_type = EVP_PKEY_RSA; } else if (strncmp(pubkey_algo, "ssh-dss", 8) == 0) { pubkey_type = EVP_PKEY_DSA; /* XXX This is where we would add support for X509 public keys, e.g.: * * x509v3-ssh-dss * x509v3-ssh-rsa * x509v3-sign (older) * */ } else { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "unsupported public key algorithm '%s' requested, rejecting request", pubkey_algo); *send_userauth_fail = TRUE; errno = EINVAL; return 0; } if (sftp_keys_verify_pubkey_type(pkt->pool, pubkey_data, pubkey_len, pubkey_type) != TRUE) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "unable to verify that given public key matches given '%s' algorithm", pubkey_algo); *send_userauth_fail = TRUE; errno = EINVAL; return 0; } #ifdef OPENSSL_FIPS if (FIPS_mode()) { fp = sftp_keys_get_fingerprint(pkt->pool, pubkey_data, pubkey_len, SFTP_KEYS_FP_DIGEST_SHA1); if (fp != NULL) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "public key SHA1 fingerprint: %s", fp); } else { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "error obtaining public key SHA1 fingerprint: %s", strerror(errno)); } } else { #endif /* OPENSSL_FIPS */ fp = sftp_keys_get_fingerprint(pkt->pool, pubkey_data, pubkey_len, SFTP_KEYS_FP_DIGEST_MD5); if (fp != NULL) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "public key MD5 fingerprint: %s", fp); } else { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "error obtaining public key MD5 fingerprint: %s", strerror(errno)); } #ifdef OPENSSL_FIPS } #endif /* OPENSSL_FIPS */ pw = pr_auth_getpwnam(pkt->pool, user); if (pw == NULL) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "no account for user '%s' found", user); pr_log_auth(PR_LOG_NOTICE, "USER %s: no such user found from %s [%s] to %s:%d", user, session.c->remote_name, pr_netaddr_get_ipstr(session.c->remote_addr), pr_netaddr_get_ipstr(session.c->local_addr), session.c->local_port); *send_userauth_fail = TRUE; errno = ENOENT; return 0; } if (!have_signature) { /* We don't perform the actual authentication just yet; we need to * let the client know that the pubkey algorithms are acceptable. */ if (send_pubkey_ok(pubkey_algo, pubkey_data, pubkey_len) < 0) { return -1; } return 0; } else { const unsigned char *id; char *buf2, *ptr2, *signature_data; uint32_t buflen2, bufsz2, id_len, signature_len; /* XXX This should become a more generic "is this key data * usable/acceptable?" check (and take the pubkey_type parameter), so that * that is where we would check the validity/usability of an X509v3 cert * (if a cert), or if the key is on the blacklist (if a key). */ if (sftp_blacklist_reject_key(pkt->pool, pubkey_data, pubkey_len)) { *send_userauth_fail = TRUE; errno = EPERM; return 0; } signature_len = sftp_msg_read_int(pkt->pool, buf, buflen); signature_data = sftp_msg_read_data(pkt->pool, buf, buflen, signature_len); /* The client signed the request as well; we need to authenticate the * user with the given pubkey now. If that succeeds, we use the * signature to verify the request. And if that succeeds, then we're * done authenticating. */ /* XXX Need to pass the pubkey_type here as well, so that the * verification routines can handle different databases of keys/certs. * * For X509v3 certs, we will want a way to enforce/restrict which * user names can be used with the provided cert. Perhaps a database * mapping cert fingerprints to user names/UIDs? Configurable callback * check (HOOK?), for modules to enforce. */ if (sftp_keystore_verify_user_key(pkt->pool, user, pubkey_data, pubkey_len) < 0) { *send_userauth_fail = TRUE; return 0; } /* Make sure the signature matches as well. */ id_len = sftp_session_get_id(&id); /* Make sure to allocate a buffer large enough to hold the publickey * signature and data we want to send back. */ bufsz2 = buflen2 = pubkey_len + 1024; ptr2 = buf2 = sftp_msg_getbuf(pkt->pool, bufsz2); sftp_msg_write_data(&buf2, &buflen2, (char *) id, id_len, TRUE); sftp_msg_write_byte(&buf2, &buflen2, SFTP_SSH2_MSG_USER_AUTH_REQUEST); sftp_msg_write_string(&buf2, &buflen2, orig_user); if (sftp_interop_supports_feature(SFTP_SSH2_FEAT_SERVICE_IN_PUBKEY_SIG)) { sftp_msg_write_string(&buf2, &buflen2, service); } else { sftp_msg_write_string(&buf2, &buflen2, "ssh-userauth"); } if (sftp_interop_supports_feature(SFTP_SSH2_FEAT_HAVE_PUBKEY_ALGO)) { sftp_msg_write_string(&buf2, &buflen2, "publickey"); sftp_msg_write_bool(&buf2, &buflen2, TRUE); sftp_msg_write_string(&buf2, &buflen2, pubkey_algo); } else { sftp_msg_write_bool(&buf2, &buflen2, TRUE); } sftp_msg_write_data(&buf2, &buflen2, pubkey_data, pubkey_len, TRUE); if (sftp_keys_verify_signed_data(pkt->pool, pubkey_algo, pubkey_data, pubkey_len, signature_data, signature_len, (unsigned char *) ptr2, (bufsz2 - buflen2)) < 0) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "failed to verify '%s' signature on public key auth request for " "user '%s'", pubkey_algo, orig_user); *send_userauth_fail = TRUE; return 0; } } /* Make sure the user is authorized to login. Normally this is checked * as part of the password verification process, but in the case of * publickey authentication, there is no password to verify. */ if (pr_auth_authorize(pkt->pool, user) != PR_AUTH_OK) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "authentication for user '%s' failed: User not authorized", user); pr_log_auth(PR_LOG_NOTICE, "USER %s (Login failed): User not authorized " "for login", user); *send_userauth_fail = TRUE; errno = EACCES; return 0; } return 1; }
static unsigned char *agent_request(pool *p, int fd, const char *path, unsigned char *req, uint32_t reqlen, uint32_t *resplen) { unsigned char msg[AGENT_REQUEST_MSGSZ], *buf, *ptr; uint32_t bufsz, buflen; int res; bufsz = buflen = sizeof(msg); buf = ptr = msg; sftp_msg_write_int(&buf, &buflen, reqlen); /* Send the message length to the agent. */ res = write(fd, ptr, (bufsz - buflen)); if (res < 0) { int xerrno = errno; pr_trace_msg(trace_channel, 3, "error sending request length to SSH agent at '%s': %s", path, strerror(xerrno)); errno = xerrno; return NULL; } /* Handle short writes. */ if (res != (bufsz - buflen)) { pr_trace_msg(trace_channel, 3, "short write (%d of %lu bytes sent) when talking to SSH agent at '%s'", res, (unsigned long) (bufsz - buflen), path); errno = EIO; return NULL; } /* Send the message payload to the agent. */ res = write(fd, req, reqlen); if (res < 0) { int xerrno = errno; pr_trace_msg(trace_channel, 3, "error sending request payload to SSH agent at '%s': %s", path, strerror(xerrno)); errno = xerrno; return NULL; } /* Handle short writes. */ if (res != reqlen) { pr_trace_msg(trace_channel, 3, "short write (%d of %lu bytes sent) when talking to SSH agent at '%s'", res, (unsigned long) reqlen, path); errno = EIO; return NULL; } /* Wait for a response from the server. */ /* XXX This needs a timeout, prevent a blocked/bad agent from stalling * the server. Maybe just set an internal timer? */ res = read(fd, msg, sizeof(uint32_t)); if (res < 0) { int xerrno = errno; pr_trace_msg(trace_channel, 3, "error reading response length from SSH agent at '%s': %s", path, strerror(xerrno)); errno = xerrno; return NULL; } /* Sanity check the returned length; we could be dealing with a buggy * client (or something else is injecting data into the Unix domain socket). * Best be conservative: if we get a response length of more than 256KB, * it's too big. (What about very long lists of keys, and/or large keys?) */ if (res > AGENT_REPLY_MAXSZ) { pr_trace_msg(trace_channel, 1, "response length (%d) from SSH agent at '%s' exceeds maximum (%lu), " "ignoring", res, path, (unsigned long) AGENT_REPLY_MAXSZ); errno = EIO; return NULL; } buf = msg; buflen = res; *resplen = sftp_msg_read_int(p, &buf, &buflen); bufsz = buflen = *resplen; buf = ptr = palloc(p, bufsz); buflen = 0; while (buflen != *resplen) { pr_signals_handle(); res = read(fd, buf + buflen, bufsz - buflen); if (res < 0) { int xerrno = errno; pr_trace_msg(trace_channel, 3, "error reading %d bytes of response payload from SSH agent at '%s': %s", (bufsz - buflen), path, strerror(xerrno)); errno = xerrno; return NULL; } /* XXX Handle short reads? */ buflen += res; } return ptr; }
const unsigned char *sftp_agent_sign_data(pool *p, const char *agent_path, const unsigned char *key_data, uint32_t key_datalen, const unsigned char *data, uint32_t datalen, uint32_t *sig_datalen) { int fd; unsigned char *buf, *req, *resp, *sig_data; uint32_t buflen, flags, reqlen, reqsz, resplen; char resp_status; fd = agent_connect(agent_path); if (fd < 0) { return NULL; } /* XXX When to set flags to OLD_SIGNATURE? */ flags = 0; /* Write out the request for signing the given data. */ reqsz = buflen = 1 + key_datalen + 4 + datalen + 4 + 4; req = buf = palloc(p, reqsz); sftp_msg_write_byte(&buf, &buflen, SFTP_SSH_AGENT_REQ_SIGN_DATA); sftp_msg_write_data(&buf, &buflen, key_data, key_datalen, TRUE); sftp_msg_write_data(&buf, &buflen, data, datalen, TRUE); sftp_msg_write_int(&buf, &buflen, flags); reqlen = reqsz - buflen; resp = agent_request(p, fd, agent_path, req, reqlen, &resplen); if (resp == NULL) { int xerrno = errno; (void) close(fd); errno = xerrno; return NULL; } (void) close(fd); /* Read the response from the agent. */ resp_status = sftp_msg_read_byte(p, &resp, &resplen); if (agent_failure(resp_status) == TRUE) { pr_trace_msg(trace_channel, 5, "SSH agent at '%s' indicated failure (%d) for data signing request", agent_path, resp_status); errno = EPERM; return NULL; } if (resp_status != SFTP_SSH_AGENT_RESP_SIGN_DATA) { pr_trace_msg(trace_channel, 5, "unknown response type %d from SSH agent at '%s'", resp_status, agent_path); errno = EACCES; return NULL; } *sig_datalen = sftp_msg_read_int(p, &resp, &resplen); sig_data = sftp_msg_read_data(p, &resp, &resplen, *sig_datalen); return sig_data; }
int sftp_agent_get_keys(pool *p, const char *agent_path, array_header *key_list) { register unsigned int i; int fd; unsigned char *buf, *req, *resp; uint32_t buflen, key_count, reqlen, reqsz, resplen; char resp_status; fd = agent_connect(agent_path); if (fd < 0) { return -1; } /* Write out the request for the identities (i.e. the public keys). */ reqsz = buflen = 64; req = buf = palloc(p, reqsz); sftp_msg_write_byte(&buf, &buflen, SFTP_SSH_AGENT_REQ_IDS); reqlen = reqsz - buflen; resp = agent_request(p, fd, agent_path, req, reqlen, &resplen); if (resp == NULL) { int xerrno = errno; (void) close(fd); errno = xerrno; return -1; } (void) close(fd); /* Read the response from the agent. */ resp_status = sftp_msg_read_byte(p, &resp, &resplen); if (agent_failure(resp_status) == TRUE) { pr_trace_msg(trace_channel, 5, "SSH agent at '%s' indicated failure (%d) for identities request", agent_path, resp_status); errno = EPERM; return -1; } if (resp_status != SFTP_SSH_AGENT_RESP_IDS) { pr_trace_msg(trace_channel, 5, "unknown response type %d from SSH agent at '%s'", resp_status, agent_path); errno = EACCES; return -1; } key_count = sftp_msg_read_int(p, &resp, &resplen); if (key_count > AGENT_MAX_KEYS) { (void) pr_log_writefile(sftp_logfd, MOD_SFTP_VERSION, "SSH agent at '%s' returned too many keys (%lu, max %lu)", agent_path, (unsigned long) key_count, (unsigned long) AGENT_MAX_KEYS); errno = EPERM; return -1; } for (i = 0; i < key_count; i++) { unsigned char *key_data; uint32_t key_datalen; char *key_comment; struct agent_key *key; key_datalen = sftp_msg_read_int(p, &resp, &resplen); key_data = sftp_msg_read_data(p, &resp, &resplen, key_datalen); key_comment = sftp_msg_read_string(p, &resp, &resplen); if (key_comment != NULL) { pr_trace_msg(trace_channel, 9, "SSH agent at '%s' provided comment '%s' for key #%u", agent_path, key_comment, (i + 1)); } key = pcalloc(p, sizeof(struct agent_key)); key->key_data = key_data; key->key_datalen = key_datalen; key->agent_path = pstrdup(p, agent_path); *((struct agent_key **) push_array(key_list)) = key; } pr_trace_msg(trace_channel, 9, "SSH agent at '%s' provided %lu %s", agent_path, (unsigned long) key_count, key_count != 1 ? "keys" : "key"); return 0; }