[asterisk-commits] bbryant: branch bbryant/iax2_rotation r115332 - /team/bbryant/iax2_rotation/c...

[SVN commits to the Asterisk project]

Author: bbryant
Date: Mon May  5 17:36:36 2008
New Revision: 115332

URL: http://svn.digium.com/view/asterisk?view=rev&rev=115332
Log:
Update iax2 rotation branch to start the testing phase after compiling it.

Modified:
    team/bbryant/iax2_rotation/channels/chan_iax2.c
    team/bbryant/iax2_rotation/channels/iax2.h

Modified: team/bbryant/iax2_rotation/channels/chan_iax2.c
URL: http://svn.digium.com/view/asterisk/team/bbryant/iax2_rotation/channels/chan_iax2.c?view=diff&rev=115332&r1=115331&r2=115332
==============================================================================
--- team/bbryant/iax2_rotation/channels/chan_iax2.c (original)
+++ team/bbryant/iax2_rotation/channels/chan_iax2.c Mon May  5 17:36:36 2008
@@ -543,6 +543,11 @@
 	unsigned char iseqno;
 	/*! Last incoming sequence number we have acknowledged */
 	unsigned char aseqno;
+	/*! time_t when RENEW is sent to change encryption key ... 
+	 * XXX (document more)
+	 * TODO: figure out a way to calculate time based on
+	 * something other than time() / time_t */
+	time_t rotatetimer;
 
 	AST_DECLARE_STRING_FIELDS(
 		/*! Peer name */
@@ -4567,6 +4572,44 @@
 		}
 	} else 
 		res = decode_frame(&iaxs[callno]->dcx, fh, f, datalen);
+	return res;
+}
+
+static int iax2_rotate(struct chan_iax2_pvt *pvt, struct iax_ies *ies)
+{
+	struct MD5Context md5;
+	unsigned char digest[16];
+
+	MD5Init(&md5);
+	MD5Update(&md5, (unsigned char *)ies->challenge, strlen(ies->challenge));
+	MD5Final(digest, &md5);
+
+	ast_aes_decrypt_key((unsigned char *)ies->challenge, &pvt->dcx);
+
+	return 0;
+}
+
+static int iax2_send_rotate(struct chan_iax2_pvt *pvt) 
+{
+	struct iax_ie_data ied;
+	struct MD5Context md5;
+	char challenge[11] = "";
+	unsigned char digest[16];
+	int res = 0;
+
+	memset(&ied, 0, sizeof(ied));
+
+	snprintf(challenge, sizeof(challenge), "%x", (int)ast_random());
+
+	iax_ie_append_raw(&ied, IAX_IE_CHALLENGE, challenge, sizeof(challenge)-1);
+	res = send_command(pvt, AST_FRAME_IAX, IAX_COMMAND_ROTATE, 0, ied.buf, ied.pos, -1);
+	
+	MD5Init(&md5);
+	MD5Update(&md5, (unsigned char *)challenge, sizeof(challenge));
+	MD5Final(digest, &md5);
+
+	ast_aes_encrypt_key(digest, &pvt->ecx);
+
 	return res;
 }
 
@@ -4699,15 +4742,21 @@
 			pvt->svideoformat = f->subclass & ~0x1;
 		if (ast_test_flag(pvt, IAX_ENCRYPTED)) {
 			if (ast_test_flag(pvt, IAX_KEYPOPULATED)) {
+				if (!pvt->rotatetimer <= time(NULL)) {
+					pvt->rotatetimer += ((pvt->rotatetimer) ? 0 : time(NULL)) + ((ast_random() % 3) + 2) * 3600;
+					iax2_send_rotate(pvt);
+				}
+
 				if (iaxdebug) {
 					if (fr->transfer)
 						iax_showframe(fr, NULL, 2, &pvt->transfer, fr->datalen - sizeof(struct ast_iax2_full_hdr));
 					else
 						iax_showframe(fr, NULL, 2, &pvt->addr, fr->datalen - sizeof(struct ast_iax2_full_hdr));
 				}
+
 				encrypt_frame(&pvt->ecx, fh, pvt->semirand, &fr->datalen);
 			} else
-				ast_log(LOG_WARNING, "Supposed to send packet encrypted, but no key?\n");
+				ast_log(LOG_WARNING, "Supposed to send packet encrypted, but no key? (no shared key found?)\n");
 		}
 	
 		if (now) {
@@ -5964,7 +6013,7 @@
 
 	iax_ie_append_short(&ied, IAX_IE_AUTHMETHODS, p->authmethods);
 	if (p->authmethods & (IAX_AUTH_MD5 | IAX_AUTH_RSA)) {
-		snprintf(challenge, sizeof(challenge), "%d", (int)ast_random());
+		snprintf(challenge, sizeof(challenge), (ast_random() & 1) ? "%x" : "%X" , (int)ast_random());
 		ast_string_field_set(p, challenge, challenge);
 		/* snprintf(p->challenge, sizeof(p->challenge), "%d", (int)ast_random()); */
 		iax_ie_append_str(&ied, IAX_IE_CHALLENGE, p->challenge);
@@ -9257,6 +9306,13 @@
 					return 1;
 				}
 				break;
+			case IAX_COMMAND_ROTATE:
+				if (!ast_test_flag(iaxs[fr->callno], IAX_ENCRYPTED) || !ast_test_flag(iaxs[fr->callno], IAX_KEYPOPULATED)) {
+					break;
+				}
+
+				iax2_rotate(iaxs[fr->callno], &ies);
+				break;
 			default:
 				ast_debug(1, "Unknown IAX command %d on %d/%d\n", f.subclass, fr->callno, iaxs[fr->callno]->peercallno);
 				memset(&ied0, 0, sizeof(ied0));

Modified: team/bbryant/iax2_rotation/channels/iax2.h
URL: http://svn.digium.com/view/asterisk/team/bbryant/iax2_rotation/channels/iax2.h?view=diff&rev=115332&r1=115331&r2=115332
==============================================================================
--- team/bbryant/iax2_rotation/channels/iax2.h (original)
+++ team/bbryant/iax2_rotation/channels/iax2.h Mon May  5 17:36:36 2008
@@ -109,6 +109,8 @@
 	IAX_COMMAND_FWDATA =    37,
 	/*! Transfer media only */
 	IAX_COMMAND_TXMEDIA =   38,
+	/*! Rotate Encryption */
+	IAX_COMMAND_ROTATE =	39,
 };
 
 /*! By default require re-registration once per minute */