client: Also try to load the private rsa-ssh key.
[paraslash.git] / client_common.c
index f34f81b..865a179 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1997-2010 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 1997-2011 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -8,8 +8,6 @@
 
 #include <regex.h>
 #include <sys/types.h>
-#include <dirent.h>
-#include <openssl/rc4.h>
 
 #include "para.h"
 #include "error.h"
 #include "sched.h"
 #include "client.cmdline.h"
 #include "crypt.h"
-#include "rc4.h"
 #include "net.h"
 #include "fd.h"
 #include "string.h"
 #include "client.cmdline.h"
 #include "client.h"
-#include "hash.h"
 #include "buffer_tree.h"
+#include "version.h"
 
 /** The size of the receiving buffer. */
 #define CLIENT_BUFSIZE 4000
@@ -40,8 +37,10 @@ void client_close(struct client_task *ct)
 {
        if (!ct)
                return;
-       if (ct->rc4c.fd >= 0)
-               close(ct->rc4c.fd);
+       if (ct->scc.fd >= 0)
+               close(ct->scc.fd);
+       sc_free(ct->scc.recv);
+       sc_free(ct->scc.send);
        free(ct->user);
        free(ct->config_file);
        free(ct->key_file);
@@ -69,19 +68,19 @@ static void client_pre_select(struct sched *s, struct task *t)
        struct client_task *ct = container_of(t, struct client_task, task);
        struct btr_node *btrn = ct->btrn;
 
-       if (ct->rc4c.fd < 0)
+       if (ct->scc.fd < 0)
                return;
        switch (ct->status) {
        case CL_CONNECTED:
        case CL_SENT_AUTH:
        case CL_SENT_CH_RESPONSE:
        case CL_SENT_COMMAND:
-               para_fd_set(ct->rc4c.fd, &s->rfds, &s->max_fileno);
+               para_fd_set(ct->scc.fd, &s->rfds, &s->max_fileno);
                return;
 
        case CL_RECEIVED_WELCOME:
        case CL_RECEIVED_PROCEED:
-               para_fd_set(ct->rc4c.fd, &s->wfds, &s->max_fileno);
+               para_fd_set(ct->scc.fd, &s->wfds, &s->max_fileno);
                return;
 
        case CL_RECEIVING:
@@ -90,7 +89,7 @@ static void client_pre_select(struct sched *s, struct task *t)
                        if (ret < 0)
                                sched_min_delay(s);
                        else
-                               para_fd_set(ct->rc4c.fd, &s->rfds,
+                               para_fd_set(ct->scc.fd, &s->rfds,
                                        &s->max_fileno);
                }
                return;
@@ -100,24 +99,36 @@ static void client_pre_select(struct sched *s, struct task *t)
                        if (ret < 0)
                                sched_min_delay(s);
                        else
-                               para_fd_set(ct->rc4c.fd, &s->wfds,
+                               para_fd_set(ct->scc.fd, &s->wfds,
                                        &s->max_fileno);
                }
                return;
        }
 }
 
-static ssize_t client_recv_buffer(struct client_task *ct, char *buf, size_t len)
+static int client_recv_buffer(struct client_task *ct, fd_set *rfds,
+               char *buf, size_t sz, size_t *n)
 {
-       ssize_t ret;
+       int ret;
 
        if (ct->status < CL_SENT_CH_RESPONSE)
-               ret = recv_buffer(ct->rc4c.fd, buf, len);
-       else
-               ret = rc4_recv_buffer(&ct->rc4c, buf, len);
+               return read_nonblock(ct->scc.fd, buf, sz, rfds, n);
+
+       *n = 0;
+       ret = sc_recv_buffer(&ct->scc, buf, sz);
+       /*
+        * sc_recv_buffer is used with blocking fds elsewhere, so it
+        * does not use the nonblock-API. Therefore we need to
+        * check for EOF and EAGAIN.
+        */
        if (ret == 0)
                return -E_SERVER_EOF;
-       return ret;
+       if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
+               return 0;
+       if (ret < 0)
+               return ret;
+       *n = ret;
+       return 0;
 }
 
 /**
@@ -138,80 +149,72 @@ static void client_post_select(struct sched *s, struct task *t)
        struct client_task *ct = container_of(t, struct client_task, task);
        struct btr_node *btrn = ct->btrn;
        int ret = 0;
+       size_t n;
        char buf[CLIENT_BUFSIZE];
 
        t->error = 0;
-       if (ct->rc4c.fd < 0)
+       if (ct->scc.fd < 0)
                return;
        switch (ct->status) {
        case CL_CONNECTED: /* receive welcome message */
-               if (!FD_ISSET(ct->rc4c.fd, &s->rfds))
-                       return;
-               ret = client_recv_buffer(ct, buf, sizeof(buf));
-               if (ret < 0)
-                       goto err;
+               ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
+               if (ret < 0 || n == 0)
+                       goto out;
                ct->status = CL_RECEIVED_WELCOME;
                return;
        case CL_RECEIVED_WELCOME: /* send auth command */
                sprintf(buf, AUTH_REQUEST_MSG "%s", ct->user);
                PARA_INFO_LOG("--> %s\n", buf);
-               if (!FD_ISSET(ct->rc4c.fd, &s->wfds))
+               if (!FD_ISSET(ct->scc.fd, &s->wfds))
                        return;
-               ret = send_buffer(ct->rc4c.fd, buf);
+               ret = send_buffer(ct->scc.fd, buf);
                if (ret < 0)
-                       goto err;
+                       goto out;
                ct->status = CL_SENT_AUTH;
                return;
        case CL_SENT_AUTH:
                /*
-                * Receive challenge and rc4 keys, decrypt the challenge and
+                * Receive challenge and session keys, decrypt the challenge and
                 * send back the hash of the decrypted challenge.
                 */
                {
-               /* decrypted challenge/rc4 buffer */
+               /* decrypted challenge/session key buffer */
                unsigned char crypt_buf[1024];
                /* the SHA1 of the decrypted challenge */
-               unsigned char challenge_sha1[HASH_SIZE];
+               unsigned char challenge_hash[HASH_SIZE];
 
-               if (!FD_ISSET(ct->rc4c.fd, &s->rfds))
-                       return;
-               ret = client_recv_buffer(ct, buf, sizeof(buf));
-               if (ret < 0)
-                       goto err;
-               PARA_INFO_LOG("<-- [challenge] (%d bytes)\n", ret);
-               ret = para_decrypt_buffer(ct->key_file, crypt_buf,
-                       (unsigned char *)buf, ret);
+               ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
+               if (ret < 0 || n == 0)
+                       goto out;
+               PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
+               ret = priv_decrypt(ct->key_file, crypt_buf,
+                       (unsigned char *)buf, n);
                if (ret < 0)
-                       goto err;
-               sha1_hash((char *)crypt_buf, CHALLENGE_SIZE, challenge_sha1);
-               RC4_set_key(&ct->rc4c.send_key, RC4_KEY_LEN,
-                       crypt_buf + CHALLENGE_SIZE);
-               RC4_set_key(&ct->rc4c.recv_key, RC4_KEY_LEN,
-                       crypt_buf + CHALLENGE_SIZE + RC4_KEY_LEN);
-               hash_to_asc(challenge_sha1, buf);
+                       goto out;
+               hash_function((char *)crypt_buf, CHALLENGE_SIZE, challenge_hash);
+               ct->scc.send = sc_new(crypt_buf + CHALLENGE_SIZE, SESSION_KEY_LEN);
+               ct->scc.recv = sc_new(crypt_buf + CHALLENGE_SIZE + SESSION_KEY_LEN,
+                       SESSION_KEY_LEN);
+               hash_to_asc(challenge_hash, buf);
                PARA_INFO_LOG("--> %s\n", buf);
-               ret = send_bin_buffer(ct->rc4c.fd, (char *)challenge_sha1,
+               ret = send_bin_buffer(ct->scc.fd, (char *)challenge_hash,
                        HASH_SIZE);
                if (ret < 0)
-                       goto err;
+                       goto out;
                ct->status = CL_SENT_CH_RESPONSE;
                return;
                }
        case CL_SENT_CH_RESPONSE: /* read server response */
                {
-               size_t bytes_received;
-               if (!FD_ISSET(ct->rc4c.fd, &s->rfds))
-                       return;
-               ret = client_recv_buffer(ct, buf, sizeof(buf));
-               if (ret < 0)
-                       goto err;
-               bytes_received = ret;
+               ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
+               if (ret < 0 || n == 0)
+                       goto out;
                /* check if server has sent "Proceed" message */
                ret = -E_CLIENT_AUTH;
-               if (bytes_received < PROCEED_MSG_LEN)
-                       goto err;
+               if (n < PROCEED_MSG_LEN)
+                       goto out;
                if (!strstr(buf, PROCEED_MSG))
-                       goto err;
+                       goto out;
                ct->status = CL_RECEIVED_PROCEED;
                return;
                }
@@ -219,7 +222,7 @@ static void client_post_select(struct sched *s, struct task *t)
                {
                int i;
                char *command = NULL;
-               if (!FD_ISSET(ct->rc4c.fd, &s->wfds))
+               if (!FD_ISSET(ct->scc.fd, &s->wfds))
                        return;
                for (i = 0; i < ct->conf.inputs_num; i++) {
                        char *tmp = command;
@@ -229,33 +232,30 @@ static void client_post_select(struct sched *s, struct task *t)
                }
                command = para_strcat(command, EOC_MSG "\n");
                PARA_DEBUG_LOG("--> %s\n", command);
-               ret = rc4_send_buffer(&ct->rc4c, command);
+               ret = sc_send_buffer(&ct->scc, command);
                free(command);
                if (ret < 0)
-                       goto err;
+                       goto out;
                ct->status = CL_SENT_COMMAND;
                return;
                }
        case CL_SENT_COMMAND:
                {
                char *buf2;
-               if (!FD_ISSET(ct->rc4c.fd, &s->rfds))
-                       return;
                /* can not use "buf" here because we need a malloced buffer */
                buf2 = para_malloc(CLIENT_BUFSIZE);
-               ret = client_recv_buffer(ct, buf2, CLIENT_BUFSIZE);
-               if (ret < 0) {
+               ret = client_recv_buffer(ct, &s->rfds, buf2, CLIENT_BUFSIZE, &n);
+               if (n > 0) {
+                       if (strstr(buf2, AWAITING_DATA_MSG)) {
+                               free(buf2);
+                               ct->status = CL_SENDING;
+                               return;
+                       }
+                       ct->status = CL_RECEIVING;
+                       btr_add_output(buf2, n, btrn);
+               } else
                        free(buf2);
-                       goto err;
-               }
-               if (strstr(buf2, AWAITING_DATA_MSG)) {
-                       free(buf2);
-                       ct->status = CL_SENDING;
-                       return;
-               }
-               ct->status = CL_RECEIVING;
-               btr_add_output(buf2, ret, btrn);
-               return;
+               goto out;
                }
        case CL_SENDING:
                {
@@ -263,15 +263,15 @@ static void client_post_select(struct sched *s, struct task *t)
                size_t sz;
                ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
                if (ret < 0)
-                       goto err;
+                       goto out;
                if (ret == 0)
                        return;
-               if (!FD_ISSET(ct->rc4c.fd, &s->wfds))
+               if (!FD_ISSET(ct->scc.fd, &s->wfds))
                        return;
                sz = btr_next_buffer(btrn, &buf2);
-               ret = rc4_send_bin_buffer(&ct->rc4c, buf2, sz);
+               ret = sc_send_bin_buffer(&ct->scc, buf2, sz);
                if (ret < 0)
-                       goto err;
+                       goto out;
                btr_consume(btrn, sz);
                return;
                }
@@ -280,23 +280,26 @@ static void client_post_select(struct sched *s, struct task *t)
                char *buf2;
                ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
                if (ret < 0)
-                       goto err;
+                       goto out;
                if (ret == 0)
                        return;
-               if (!FD_ISSET(ct->rc4c.fd, &s->rfds))
+               /*
+                * The FD_ISSET() is not strictly necessary, but is allows us
+                * to skip the malloc below if there is nothing to read anyway.
+                */
+               if (!FD_ISSET(ct->scc.fd, &s->rfds))
                        return;
                buf2 = para_malloc(CLIENT_BUFSIZE);
-               ret = client_recv_buffer(ct, buf2, CLIENT_BUFSIZE);
-               if (ret < 0) {
+               ret = client_recv_buffer(ct, &s->rfds, buf2, CLIENT_BUFSIZE, &n);
+               if (n > 0) {
+                       buf2 = para_realloc(buf2, n);
+                       btr_add_output(buf2, n, btrn);
+               } else
                        free(buf2);
-                       goto err;
-               }
-               buf2 = para_realloc(buf2, ret);
-               btr_add_output(buf2, ret, btrn);
-               return;
+               goto out;
                }
        }
-err:
+out:
        t->error = ret;
        if (ret < 0) {
                if (ret != -E_SERVER_EOF && ret != -E_BTR_EOF)
@@ -310,14 +313,14 @@ static int client_connect(struct client_task *ct)
 {
        int ret;
 
-       ct->rc4c.fd = -1;
+       ct->scc.fd = -1;
        ret = para_connect_simple(IPPROTO_TCP, ct->conf.hostname_arg,
                                               ct->conf.server_port_arg);
        if (ret < 0)
                return ret;
-       ct->rc4c.fd = ret;
+       ct->scc.fd = ret;
        ct->status = CL_CONNECTED;
-       ret = mark_fd_nonblocking(ct->rc4c.fd);
+       ret = mark_fd_nonblocking(ct->scc.fd);
        if (ret < 0)
                goto err_out;
        ct->task.pre_select = client_pre_select;
@@ -326,8 +329,8 @@ static int client_connect(struct client_task *ct)
        register_task(&ct->task);
        return 1;
 err_out:
-       close(ct->rc4c.fd);
-       ct->rc4c.fd = -1;
+       close(ct->scc.fd);
+       ct->scc.fd = -1;
        return ret;
 }
 
@@ -358,7 +361,7 @@ int client_open(int argc, char *argv[], struct client_task **ct_ptr,
        ct->btrn = btr_new_node(&(struct btr_node_description)
                EMBRACE(.name = "client", .parent = parent, .child = child));
        *ct_ptr = ct;
-       ct->rc4c.fd = -1;
+       ct->scc.fd = -1;
        ret = -E_CLIENT_SYNTAX;
        if (client_cmdline_parser(argc, argv, &ct->conf))
                goto out;
@@ -391,9 +394,16 @@ int client_open(int argc, char *argv[], struct client_task **ct_ptr,
        ct->user = ct->conf.user_given?
                para_strdup(ct->conf.user_arg) : para_logname();
 
-       ct->key_file = ct->conf.key_file_given?
-               para_strdup(ct->conf.key_file_arg) :
-               make_message("%s/.paraslash/key.%s", home, ct->user);
+       if (ct->conf.key_file_given)
+               ct->key_file = para_strdup(ct->conf.key_file_arg);
+       else {
+               ct->key_file = make_message("%s/.paraslash/key.%s",
+                       home, ct->user);
+               if (!file_exists(ct->key_file)) {
+                       free(ct->key_file);
+                       ct->key_file = make_message("%s/.ssh/id_rsa", home);
+               }
+       }
 
        if (loglevel)
                *loglevel = get_loglevel_by_name(ct->conf.loglevel_arg);