X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=client_common.c;h=dd951c15061948304343c5d26cf69d1c5f9f4fb1;hp=b1eaa78b2db7563b699c6993509e738b12f665a8;hb=672e27768e31a6eaa6854d4fc75ee6885db9abd8;hpb=a9126f461792a84c760162ecb25100f1593d427d

diff --git a/client_common.c b/client_common.c
index b1eaa78b..dd951c15 100644
--- a/client_common.c
+++ b/client_common.c
@@ -22,6 +22,7 @@
 #include "string.h"
 #include "client.cmdline.h"
 #include "client.h"
+#include "hash.h"
 
 /**
  * Close the connection to para_server and free all resources.
@@ -110,7 +111,7 @@ static ssize_t client_recv_buffer(struct client_task *ct)
 {
 	ssize_t ret;
 
-	if (ct->status < CL_RECEIVED_PROCEED)
+	if (ct->status < CL_SENT_CH_RESPONSE)
 		ret = recv_buffer(ct->rc4c.fd, ct->buf + ct->loaded,
 			CLIENT_BUFSIZE - ct->loaded);
 	else
@@ -121,7 +122,6 @@ static ssize_t client_recv_buffer(struct client_task *ct)
 	if (ret > 0)
 		ct->loaded += ret;
 	return ret;
-
 }
 
 /**
@@ -140,6 +140,7 @@ static ssize_t client_recv_buffer(struct client_task *ct)
 static void client_post_select(struct sched *s, struct task *t)
 {
 	struct client_task *ct = container_of(t, struct client_task, task);
+	unsigned char crypt_buf[1024];
 
 	t->error = 0;
 	if (ct->rc4c.fd < 0)
@@ -153,66 +154,65 @@ static void client_post_select(struct sched *s, struct task *t)
 	switch (ct->status) {
 	case CL_CONNECTED: /* receive welcome message */
 		t->error = client_recv_buffer(ct);
-		if (t->error > 0)
-			ct->status = CL_RECEIVED_WELCOME;
+		if (t->error < 0)
+			goto err;
+		ct->status = CL_RECEIVED_WELCOME;
 		return;
 	case CL_RECEIVED_WELCOME: /* send auth command */
-		sprintf(ct->buf, "auth rc4 %s", ct->user);
+		sprintf(ct->buf, AUTH_REQUEST_MSG "%s", ct->user);
 		PARA_INFO_LOG("--> %s\n", ct->buf);
 		t->error = send_buffer(ct->rc4c.fd, ct->buf);
-		if (t->error >= 0)
-			ct->status = CL_SENT_AUTH;
+		if (t->error < 0)
+			goto err;
+		ct->status = CL_SENT_AUTH;
 		return;
-	case CL_SENT_AUTH: /* receive challenge number */
+	case CL_SENT_AUTH: /* receive challenge and rc4 keys */
 		ct->loaded = 0;
 		t->error = client_recv_buffer(ct);
 		if (t->error < 0)
-			return;
-		if (t->error != 64) {
-			t->error = -E_INVALID_CHALLENGE;
-			PARA_ERROR_LOG("received the following: %s\n", ct->buf);
-			return;
-		}
-		PARA_INFO_LOG("<-- [challenge]\n");
-		/* decrypt challenge number */
-		t->error = para_decrypt_challenge(ct->key_file, &ct->challenge_nr,
-			(unsigned char *) ct->buf, 64);
-		if (t->error > 0)
-			ct->status = CL_RECEIVED_CHALLENGE;
+			goto err;
+		PARA_INFO_LOG("<-- [challenge] (%d bytes)\n", t->error);
+		/* decrypt challenge/rc4 buffer  */
+		t->error = para_decrypt_buffer(ct->key_file, crypt_buf,
+			(unsigned char *)ct->buf, t->error);
+		if (t->error < 0)
+			goto err;
+		ct->status = CL_RECEIVED_CHALLENGE;
+		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);
 		return;
-	case CL_RECEIVED_CHALLENGE: /* send decrypted challenge */
-		PARA_INFO_LOG("--> %lu\n", ct->challenge_nr);
-		t->error = send_va_buffer(ct->rc4c.fd, "%s%lu", CHALLENGE_RESPONSE_MSG,
-			ct->challenge_nr);
-		if (t->error > 0)
-			ct->status = CL_SENT_CH_RESPONSE;
+	case CL_RECEIVED_CHALLENGE:
+		{
+		unsigned char challenge_sha1[HASH_SIZE];
+		/* send sha1 of decrypted challenge */
+		sha1_hash((char *)crypt_buf, CHALLENGE_SIZE, challenge_sha1);
+		hash_to_asc(challenge_sha1, ct->buf);
+		PARA_INFO_LOG("--> %s\n", ct->buf);
+		t->error = send_bin_buffer(ct->rc4c.fd, (char *)challenge_sha1,
+			HASH_SIZE);
+		if (t->error < 0)
+			goto err;
+		ct->status = CL_SENT_CH_RESPONSE;
 		return;
+		}
 	case CL_SENT_CH_RESPONSE: /* read server response */
 		{
 		size_t bytes_received;
-		unsigned char rc4_buf[2 * RC4_KEY_LEN] = "";
 		ct->loaded = 0;
 		t->error = client_recv_buffer(ct);
 		if (t->error < 0)
-			return;
+			goto err;
 		bytes_received = t->error;
-		PARA_DEBUG_LOG("++++ server info ++++\n%s\n++++ end of server "
-			"info ++++\n", ct->buf);
-		/* check if server has sent "Proceed" message and the rc4 keys */
+		/* check if server has sent "Proceed" message */
 		t->error = -E_CLIENT_AUTH;
-		if (bytes_received < PROCEED_MSG_LEN + 2 * RC4_KEY_LEN)
-			return;
+		if (bytes_received < PROCEED_MSG_LEN)
+			goto err;
 		if (!strstr(ct->buf, PROCEED_MSG))
-			return;
-		PARA_INFO_LOG("decrypting session key\n");
-		t->error = para_decrypt_buffer(ct->key_file, rc4_buf,
-			(unsigned char *)ct->buf + PROCEED_MSG_LEN + 1,
-			bytes_received - PROCEED_MSG_LEN - 1);
-		if (t->error < 0)
-			return;
-		RC4_set_key(&ct->rc4c.send_key, RC4_KEY_LEN, rc4_buf);
-		RC4_set_key(&ct->rc4c.recv_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
+			goto err;
 		ct->status = CL_RECEIVED_PROCEED;
+		t->error = 0;
 		return;
 		}
 	case CL_RECEIVED_PROCEED: /* concat args and send command */
@@ -229,31 +229,38 @@ static void client_post_select(struct sched *s, struct task *t)
 		PARA_DEBUG_LOG("--> %s\n", command);
 		t->error = rc4_send_buffer(&ct->rc4c, command);
 		free(command);
-		if (t->error > 0)
-			ct->status = CL_SENT_COMMAND;
+		if (t->error < 0)
+			goto err;
+		ct->status = CL_SENT_COMMAND;
 		return;
 		}
 	case CL_SENT_COMMAND:
 		ct->loaded = 0;
 		t->error = client_recv_buffer(ct);
 		if (t->error < 0)
-			return;
+			goto err;
 		if (strstr(ct->buf, AWAITING_DATA_MSG))
 			ct->status = CL_SENDING;
 		else
 			ct->status = CL_RECEIVING;
 		return;
-	case CL_SENDING: /* FIXME: might block */
+	case CL_SENDING:
 		PARA_INFO_LOG("loaded: %zd\n", *ct->in_loaded);
-		t->error = rc4_send_bin_buffer(&ct->rc4c, ct->inbuf, *ct->in_loaded);
+		t->error = rc4_send_bin_buffer(&ct->rc4c, ct->inbuf,
+			*ct->in_loaded);
 		if (t->error < 0)
-			return;
+			goto err;
 		*ct->in_loaded = 0;
 		return;
 	case CL_RECEIVING:
 		t->error = client_recv_buffer(ct);
+		if (t->error < 0)
+			goto err;
 		return;
 	}
+err:
+	if (t->error != -E_SERVER_EOF)
+		PARA_ERROR_LOG("%s\n", para_strerror(-t->error));
 }
 
 /* connect to para_server and register the client task */