diald/sme9/diald-1.0.buffer.patch

diff -ru diald-1.0.orig/buffer.c diald-1.0/buffer.c
--- diald-1.0.orig/buffer.c     2001-06-16 15:51:39.000000000 -0400
+++ diald-1.0/buffer.c  2005-10-04 10:38:22.331362000 -0400
@@ -3,6 +3,7 @@
  *
  * Copyright (c) 1994, 1995, 1996 Eric Schenk.
  * Copyright (c) 1999 Mike Jagdis.
+ * Copyright (c) 2002 Jason Turner.
  * All rights reserved. Please see the file LICENSE which should be
  * distributed with this software for terms of use.
  */
@@ -11,90 +12,195 @@
 
 #include <diald.h>
 
+#define BUFFER_CHUNK_SIZE_MAX 4096
 
-#define B(i) buffer[(i)%buffer_size]
-
-static int oldsize = 0;
-static unsigned char *buffer = 0;
-static int head = 0;
-static int used = 0;
-static int tail = 0;
+#ifndef UINT_MAX
+#define UINT_MAX (~0U)
+#endif
 
-void buffer_init(int *var, char **argv)
-{
-    buffer_size = atoi(*argv);
-    if (buffer_size != oldsize) {
-       if (buffer)
-               free(buffer);
-       buffer = malloc(buffer_size);
-       oldsize = buffer_size;
+struct bpkt_hdr {                      /* Buffered packet header */
+    unsigned long expires;             /* When it expires in uptime secs */
+    unsigned int len;                  /* Length of following packet,
+                                        * up to BUFFER_CHUNK_SIZE_MAX */
+};
+
+static char *buffer = 0;               /* start address of ring buffer */
+static char *buffer_end = 0;           /* end address (+1) of ring buffer */
+static unsigned int true_size = 0;     /* actual size of buffer */
+static unsigned int used = 0;          /* bytes used */
+static unsigned int head = 0;          /* read offset */
+static unsigned int tail = 0;          /* write offset */
+
+/* buffer_setup()
+ * Create/recreate/delete the buffer and setup pointers.
+ * Returns the actual buffer size.
+ * The buffer_size variable is declared in diald.h and is given an initial
+ * value in options.c .
+ */
+static unsigned int buffer_setup() {
+    if ( buffer_size < 0 || buffer_size > UINT_MAX ) {
+       mon_syslog(LOG_ERR,"Ignoring invalid buffer_size request.");
+    } else {
+       /* discard existing buffer and any contents */
+       if (buffer) {
+           free(buffer);
+           buffer = 0;
+       }
+       true_size = 0; used = 0; head = 0; tail = 0;
+       if (buffer_size) {
+           /* create new buffer */
+           if (buffer = malloc(buffer_size)) {
+               true_size = buffer_size;
+               buffer_end = buffer + true_size;
+           } else {
+               mon_syslog(LOG_ERR, "Out of memory! Cannot create ring buffer.");
+               /* This is not fatal. diald will run fine without the buffer. */
+           }
+       }
     }
+    return true_size;
 }
 
+/* buffer_check()
+ * If there is no buffer_size param in the config file, the buffer is not
+ * initially set up!
+ * So call this from forward_buffer() and buffer_packet()
+ */
 static void buffer_check()
 {
-    if (!buffer) {
-       buffer = malloc(buffer_size);
-       oldsize = buffer_size;
+    if (buffer)
+       return;
+    if (!buffer_setup()) {
+       /* if we cannot create a buffer, then disable the feature to avoid
+        * repeated calls.  */
+       buffer_packets = 0;
+       mon_syslog(LOG_WARNING,"No buffer: buffer-packets feature disabled.");
     }
 }
 
+/* buffer_write()
+ * Write data to the ring buffer, adjust tail offset and space used
+ * Should not be called unless sure there is enough free space
+ */
+static void buffer_write(unsigned int count, char *pkt) {
+    char *write_ptr = buffer + tail;
+
+    if (write_ptr + count > buffer_end) {
+       unsigned int count2end = buffer_end - write_ptr;
+       memcpy(write_ptr, pkt, count2end);
+       memcpy(buffer, pkt + count2end, count - count2end);
+    } else {
+       memcpy(write_ptr, pkt, count);
+    }
+    tail = (tail+count)%true_size;
+    used += count;
+}
 
-void buffer_packet(unsigned int len,unsigned char *pkt)
+/* buffer_read()
+ * Read bytes from ring buffer. Do not delete.
+ * Should not be called unless used is positive.
+ */
+static void buffer_read(unsigned int count, char *pkt) {
+    char *read_ptr = buffer + head;
+
+    if (read_ptr + count > buffer_end) {
+       unsigned int count2end = buffer_end - read_ptr;
+       memcpy(pkt, read_ptr, count2end);
+       memcpy(pkt + count2end, buffer, count - count2end);
+    } else {
+       memcpy(pkt, read_ptr, count);
+    }
+}
+
+/* buffer_dispose()
+ * Delete from ring buffer by adjusting read offset
+ */
+static void buffer_dispose(unsigned int count) {
+    head = (head+count)%true_size;
+    used -= count;
+}
+
+/* externally linked functions */
+
+/* buffer_init()
+ * This is called when reading the config file or command line options.
+ * There will be at least one argument, but the arg was not checked to be a
+ * numeric string.
+ */
+void buffer_init(int *var, char **argv)
+{
+    buffer_size = strtol(*argv, NULL, 0);
+    if (buffer_size != true_size)
+       buffer_setup();
+}
+
+/* buffer_packet()
+ * Place packet into the ring.
+ */
+void buffer_packet(unsigned int len, unsigned char *pkt)
 {
-    unsigned int clen;
-    unsigned long stamp;
+    struct bpkt_hdr pkt_hdr;
     unsigned long ctime = timestamp();
+    unsigned int space_needed = len + sizeof(struct bpkt_hdr);
+
+    if (len > BUFFER_CHUNK_SIZE_MAX) {
+       mon_syslog(LOG_WARNING, "Packet too large to buffer: %d", len);
+       return;
+    }
 
     buffer_check();
-    if (len+6 > buffer_size) {
+
+    if (space_needed > true_size) {
        mon_syslog(LOG_NOTICE,
            "Can't buffer packet of length %d, buffer too small",
            len);
        return;
     }
+
+    /* TODO
+     * Add buffer filtering ?
+     * eg. ntp packets do not fare well to long delays
+     * The expires time could also be different for each packet.
+     */
+
     if (buffer_fifo_dispose) {
        /* toss from the front of the buffer till we have space */
-       while (used+len+6 > buffer_size) {
-           clen = (B(head)<<8) | B(head+1);
-           head = (head+6+clen)%buffer_size;
-           used -= (6+clen);
+       while (used + space_needed > true_size) {
+           buffer_read(sizeof(struct bpkt_hdr), (char *)&pkt_hdr);
+           buffer_dispose(sizeof(struct bpkt_hdr) + pkt_hdr.len);
        }
     } else {
+       /* toss out expired packets from front of buffer
+        * Any expired packets in the middle will be killed when forwarding
+        */
        for (;;) {
-           clen = (B(head)<<8) | B(head+1);
-           stamp = (B(head+2)<<24) | (B(head+3)<<16) | (B(head+4)<<8) | B(head+5);
-           if (stamp+buffer_timeout >= ctime)
+           if (!used)
+               break;
+           buffer_read(sizeof(struct bpkt_hdr), (char *)&pkt_hdr);
+           if (pkt_hdr.expires >= ctime)
                break;
-           head = (head+6+clen)%buffer_size;
-           used -= (6+clen);
+           buffer_dispose(sizeof(struct bpkt_hdr) + pkt_hdr.len);
        }
     }
-    if (used+len+6 <= buffer_size) {
-       used = used + 6 + len;
-       B(tail) = (len>>8)&0xff;
-       B(tail+1) = len&0xff;
-       B(tail+2) = (ctime>>24)&0xff;
-       B(tail+3) = (ctime>>16)&0xff;
-       B(tail+4) = (ctime>>8)&0xff;
-       B(tail+5) = ctime&0xff;
-       tail = (tail+6)%buffer_size;
-       while (len--) {
-           buffer[tail] = *pkt++;
-           tail = (tail+1)%buffer_size;
-       }
+    if (used + space_needed <= true_size) {
+       pkt_hdr.len = len;
+       pkt_hdr.expires = ctime + buffer_timeout;
+       buffer_write(sizeof(struct bpkt_hdr), (char *)&pkt_hdr);
+       buffer_write(len, pkt);
     } else {
        mon_syslog(LOG_NOTICE,
            "Can't buffer packet of length %d, only %d bytes available.",
-           len,buffer_size-(used+6));
+           len, true_size - ( used + sizeof(struct bpkt_hdr) ) );
     }
 }
 
+/* forward_buffer()
+ * Clears ring buffer and sends unexpired packets on their way.
+ */
 void forward_buffer()
 {
+    struct bpkt_hdr pkt_hdr;
     int forwarding = 0;
-    unsigned int clen, i;
-    unsigned long stamp;
     unsigned long ctime = timestamp();
     struct sockaddr_pkt sp;
 #ifdef HAVE_AF_PACKET
@@ -102,7 +208,7 @@
 #endif
     struct sockaddr *to;
     size_t to_len;
-    unsigned char pkt[4096];
+    char pkt[BUFFER_CHUNK_SIZE_MAX];
 
 #ifdef __linux__
     /* If we are using dynamic addresses we need to know whether we
@@ -141,19 +247,19 @@
     }
 
     while (used > 0) {
-       clen = (B(head)<<8) | B(head+1);
-       stamp = (B(head+2)<<24) | (B(head+3)<<16) | (B(head+4)<<8) | B(head+5);
-        if (stamp+buffer_timeout >= ctime) {
+       buffer_read(sizeof(struct bpkt_hdr), (char *)&pkt_hdr);
+       buffer_dispose(sizeof(struct bpkt_hdr));
+        if (pkt_hdr.expires >= ctime) {
            unsigned short wprot;
-           unsigned char *dpkt;
+           char *dpkt;
            unsigned int dlen;
 
-           for (i = 0; i < clen; i++)
-               pkt[i] = B(head+6+i);
+           buffer_read(pkt_hdr.len, pkt);
 
+           /* strip off the protocol from the raw packet */
            wprot = *(unsigned short *)pkt;
            dpkt = pkt + sizeof(unsigned short);
-           dlen = clen - sizeof(unsigned short);
+           dlen = pkt_hdr.len - sizeof(unsigned short);
 
            /* If we are using dynamic addresses and forwarding traffic
             * we send the packet back in to the kernel on the proxy so
@@ -180,7 +286,6 @@
                    mon_syslog(LOG_ERR,"Error forwarding data packet to physical device from buffer: %m");
            }
        }
-       head = (head+6+clen)%buffer_size;
-       used -= (6+clen);
+       buffer_dispose(pkt_hdr.len);
     }
 }
1	wellsi	1.1	diff -ru diald-1.0.orig/buffer.c diald-1.0/buffer.c
2			--- diald-1.0.orig/buffer.c 2001-06-16 15:51:39.000000000 -0400
3			+++ diald-1.0/buffer.c 2005-10-04 10:38:22.331362000 -0400
4			@@ -3,6 +3,7 @@
5			*
6			* Copyright (c) 1994, 1995, 1996 Eric Schenk.
7			* Copyright (c) 1999 Mike Jagdis.
8			+ * Copyright (c) 2002 Jason Turner.
9			* All rights reserved. Please see the file LICENSE which should be
10			* distributed with this software for terms of use.
11			*/
12			@@ -11,90 +12,195 @@
13
14			#include <diald.h>
15
16			+#define BUFFER_CHUNK_SIZE_MAX 4096
17
18			-#define B(i) buffer[(i)%buffer_size]
19			-
20			-static int oldsize = 0;
21			-static unsigned char *buffer = 0;
22			-static int head = 0;
23			-static int used = 0;
24			-static int tail = 0;
25			+#ifndef UINT_MAX
26			+#define UINT_MAX (~0U)
27			+#endif
28
29			-void buffer_init(int var, char *argv)
30			-{
31			- buffer_size = atoi(*argv);
32			- if (buffer_size != oldsize) {
33			- if (buffer)
34			- free(buffer);
35			- buffer = malloc(buffer_size);
36			- oldsize = buffer_size;
37			+struct bpkt_hdr { /* Buffered packet header */
38			+ unsigned long expires; /* When it expires in uptime secs */
39			+ unsigned int len; /* Length of following packet,
40			+ * up to BUFFER_CHUNK_SIZE_MAX */
41			+};
42			+
43			+static char buffer = 0; / start address of ring buffer */
44			+static char buffer_end = 0; / end address (+1) of ring buffer */
45			+static unsigned int true_size = 0; /* actual size of buffer */
46			+static unsigned int used = 0; /* bytes used */
47			+static unsigned int head = 0; /* read offset */
48			+static unsigned int tail = 0; /* write offset */
49			+
50			+/* buffer_setup()
51			+ * Create/recreate/delete the buffer and setup pointers.
52			+ * Returns the actual buffer size.
53			+ * The buffer_size variable is declared in diald.h and is given an initial
54			+ * value in options.c .
55			+ */
56			+static unsigned int buffer_setup() {
57			+ if ( buffer_size < 0 \|\| buffer_size > UINT_MAX ) {
58			+ mon_syslog(LOG_ERR,"Ignoring invalid buffer_size request.");
59			+ } else {
60			+ /* discard existing buffer and any contents */
61			+ if (buffer) {
62			+ free(buffer);
63			+ buffer = 0;
64			+ }
65			+ true_size = 0; used = 0; head = 0; tail = 0;
66			+ if (buffer_size) {
67			+ /* create new buffer */
68			+ if (buffer = malloc(buffer_size)) {
69			+ true_size = buffer_size;
70			+ buffer_end = buffer + true_size;
71			+ } else {
72			+ mon_syslog(LOG_ERR, "Out of memory! Cannot create ring buffer.");
73			+ /* This is not fatal. diald will run fine without the buffer. */
74			+ }
75			+ }
76			}
77			+ return true_size;
78			}
79
80			+/* buffer_check()
81			+ * If there is no buffer_size param in the config file, the buffer is not
82			+ * initially set up!
83			+ * So call this from forward_buffer() and buffer_packet()
84			+ */
85			static void buffer_check()
86			{
87			- if (!buffer) {
88			- buffer = malloc(buffer_size);
89			- oldsize = buffer_size;
90			+ if (buffer)
91			+ return;
92			+ if (!buffer_setup()) {
93			+ /* if we cannot create a buffer, then disable the feature to avoid
94			+ * repeated calls. */
95			+ buffer_packets = 0;
96			+ mon_syslog(LOG_WARNING,"No buffer: buffer-packets feature disabled.");
97			}
98			}
99
100			+/* buffer_write()
101			+ * Write data to the ring buffer, adjust tail offset and space used
102			+ * Should not be called unless sure there is enough free space
103			+ */
104			+static void buffer_write(unsigned int count, char *pkt) {
105			+ char *write_ptr = buffer + tail;
106			+
107			+ if (write_ptr + count > buffer_end) {
108			+ unsigned int count2end = buffer_end - write_ptr;
109			+ memcpy(write_ptr, pkt, count2end);
110			+ memcpy(buffer, pkt + count2end, count - count2end);
111			+ } else {
112			+ memcpy(write_ptr, pkt, count);
113			+ }
114			+ tail = (tail+count)%true_size;
115			+ used += count;
116			+}
117
118			-void buffer_packet(unsigned int len,unsigned char *pkt)
119			+/* buffer_read()
120			+ * Read bytes from ring buffer. Do not delete.
121			+ * Should not be called unless used is positive.
122			+ */
123			+static void buffer_read(unsigned int count, char *pkt) {
124			+ char *read_ptr = buffer + head;
125			+
126			+ if (read_ptr + count > buffer_end) {
127			+ unsigned int count2end = buffer_end - read_ptr;
128			+ memcpy(pkt, read_ptr, count2end);
129			+ memcpy(pkt + count2end, buffer, count - count2end);
130			+ } else {
131			+ memcpy(pkt, read_ptr, count);
132			+ }
133			+}
134			+
135			+/* buffer_dispose()
136			+ * Delete from ring buffer by adjusting read offset
137			+ */
138			+static void buffer_dispose(unsigned int count) {
139			+ head = (head+count)%true_size;
140			+ used -= count;
141			+}
142			+
143			+/* externally linked functions */
144			+
145			+/* buffer_init()
146			+ * This is called when reading the config file or command line options.
147			+ * There will be at least one argument, but the arg was not checked to be a
148			+ * numeric string.
149			+ */
150			+void buffer_init(int var, char *argv)
151			+{
152			+ buffer_size = strtol(*argv, NULL, 0);
153			+ if (buffer_size != true_size)
154			+ buffer_setup();
155			+}
156			+
157			+/* buffer_packet()
158			+ * Place packet into the ring.
159			+ */
160			+void buffer_packet(unsigned int len, unsigned char *pkt)
161			{
162			- unsigned int clen;
163			- unsigned long stamp;
164			+ struct bpkt_hdr pkt_hdr;
165			unsigned long ctime = timestamp();
166			+ unsigned int space_needed = len + sizeof(struct bpkt_hdr);
167			+
168			+ if (len > BUFFER_CHUNK_SIZE_MAX) {
169			+ mon_syslog(LOG_WARNING, "Packet too large to buffer: %d", len);
170			+ return;
171			+ }
172
173			buffer_check();
174			- if (len+6 > buffer_size) {
175			+
176			+ if (space_needed > true_size) {
177			mon_syslog(LOG_NOTICE,
178			"Can't buffer packet of length %d, buffer too small",
179			len);
180			return;
181			}
182			+
183			+ /* TODO
184			+ * Add buffer filtering ?
185			+ * eg. ntp packets do not fare well to long delays
186			+ * The expires time could also be different for each packet.
187			+ */
188			+
189			if (buffer_fifo_dispose) {
190			/* toss from the front of the buffer till we have space */
191			- while (used+len+6 > buffer_size) {
192			- clen = (B(head)<<8) \| B(head+1);
193			- head = (head+6+clen)%buffer_size;
194			- used -= (6+clen);
195			+ while (used + space_needed > true_size) {
196			+ buffer_read(sizeof(struct bpkt_hdr), (char *)&pkt_hdr);
197			+ buffer_dispose(sizeof(struct bpkt_hdr) + pkt_hdr.len);
198			}
199			} else {
200			+ /* toss out expired packets from front of buffer
201			+ * Any expired packets in the middle will be killed when forwarding
202			+ */
203			for (;;) {
204			- clen = (B(head)<<8) \| B(head+1);
205			- stamp = (B(head+2)<<24) \| (B(head+3)<<16) \| (B(head+4)<<8) \| B(head+5);
206			- if (stamp+buffer_timeout >= ctime)
207			+ if (!used)
208			+ break;
209			+ buffer_read(sizeof(struct bpkt_hdr), (char *)&pkt_hdr);
210			+ if (pkt_hdr.expires >= ctime)
211			break;
212			- head = (head+6+clen)%buffer_size;
213			- used -= (6+clen);
214			+ buffer_dispose(sizeof(struct bpkt_hdr) + pkt_hdr.len);
215			}
216			}
217			- if (used+len+6 <= buffer_size) {
218			- used = used + 6 + len;
219			- B(tail) = (len>>8)&0xff;
220			- B(tail+1) = len&0xff;
221			- B(tail+2) = (ctime>>24)&0xff;
222			- B(tail+3) = (ctime>>16)&0xff;
223			- B(tail+4) = (ctime>>8)&0xff;
224			- B(tail+5) = ctime&0xff;
225			- tail = (tail+6)%buffer_size;
226			- while (len--) {
227			- buffer[tail] = *pkt++;
228			- tail = (tail+1)%buffer_size;
229			- }
230			+ if (used + space_needed <= true_size) {
231			+ pkt_hdr.len = len;
232			+ pkt_hdr.expires = ctime + buffer_timeout;
233			+ buffer_write(sizeof(struct bpkt_hdr), (char *)&pkt_hdr);
234			+ buffer_write(len, pkt);
235			} else {
236			mon_syslog(LOG_NOTICE,
237			"Can't buffer packet of length %d, only %d bytes available.",
238			- len,buffer_size-(used+6));
239			+ len, true_size - ( used + sizeof(struct bpkt_hdr) ) );
240			}
241			}
242
243			+/* forward_buffer()
244			+ * Clears ring buffer and sends unexpired packets on their way.
245			+ */
246			void forward_buffer()
247			{
248			+ struct bpkt_hdr pkt_hdr;
249			int forwarding = 0;
250			- unsigned int clen, i;
251			- unsigned long stamp;
252			unsigned long ctime = timestamp();
253			struct sockaddr_pkt sp;
254			#ifdef HAVE_AF_PACKET
255			@@ -102,7 +208,7 @@
256			#endif
257			struct sockaddr *to;
258			size_t to_len;
259			- unsigned char pkt[4096];
260			+ char pkt[BUFFER_CHUNK_SIZE_MAX];
261
262			#ifdef __linux__
263			/* If we are using dynamic addresses we need to know whether we
264			@@ -141,19 +247,19 @@
265			}
266
267			while (used > 0) {
268			- clen = (B(head)<<8) \| B(head+1);
269			- stamp = (B(head+2)<<24) \| (B(head+3)<<16) \| (B(head+4)<<8) \| B(head+5);
270			- if (stamp+buffer_timeout >= ctime) {
271			+ buffer_read(sizeof(struct bpkt_hdr), (char *)&pkt_hdr);
272			+ buffer_dispose(sizeof(struct bpkt_hdr));
273			+ if (pkt_hdr.expires >= ctime) {
274			unsigned short wprot;
275			- unsigned char *dpkt;
276			+ char *dpkt;
277			unsigned int dlen;
278
279			- for (i = 0; i < clen; i++)
280			- pkt[i] = B(head+6+i);
281			+ buffer_read(pkt_hdr.len, pkt);
282
283			+ /* strip off the protocol from the raw packet */
284			wprot = (unsigned short )pkt;
285			dpkt = pkt + sizeof(unsigned short);
286			- dlen = clen - sizeof(unsigned short);
287			+ dlen = pkt_hdr.len - sizeof(unsigned short);
288
289			/* If we are using dynamic addresses and forwarding traffic
290			* we send the packet back in to the kernel on the proxy so
291			@@ -180,7 +286,6 @@
292			mon_syslog(LOG_ERR,"Error forwarding data packet to physical device from buffer: %m");
293			}
294			}
295			- head = (head+6+clen)%buffer_size;
296			- used -= (6+clen);
297			+ buffer_dispose(pkt_hdr.len);
298			}
299			}