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* SendMessageOptions: Increase tag fields to 4 bits and use

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table lookup for more flexibility
 * Streaming: Use packet type and current window size to adjust
              number of tags sent and tag threshold, to improve
              efficiency and reliability
This commit is contained in:
zzz
2012-08-26 13:02:11 +00:00
parent 9ba6c293ed
commit b01cf32321
5 changed files with 91 additions and 66 deletions
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87
core/java/src/net/i2p/client/SendMessageOptions.java
View File

@ -21,39 +21,32 @@ public class SendMessageOptions extends DateAndFlags {
/**
* 1 means don't send, 0 means default
*/
private static final int LS_MASK = 0x0001;
private static final int LS_MASK = 0x0100;
/**
* Tags to send field:
*<pre>
* 000 - default
* 001 - 2
* 010 - 4
* 011 - 8
* 100 - 16
* 101 - 32
* 110 - 64
* 111 - 128
*</pre>
* see below for possible values
*/
private static final int TAGS_SEND_MASK = 0x000e;
private static final int MAX_SEND_TAGS = 128;
private static final int TAGS_SEND_MASK = 0x000f;
/**
* Possible values. Configured values will be rounded down.
* Note that ElGamalAESEngine enforces a max of 200 on receive.
*/
private static final int[] TAGS_SEND = {
0, 2, 4, 6, 8, 12, 16, 24,
32, 40, 51, 64, 80, 100, 125, 160
};
/**
* Tags threshold field:
*<pre>
* 000 - default
* 001 - 1
* 010 - 2
* 011 - 4
* 100 - 8
* 101 - 16
* 110 - 32
* 111 - 64
*</pre>
* see below for possible values
*/
private static final int TAGS_REQD_MASK = 0x0070;
private static final int MAX_REQD_TAGS = 64;
private static final int TAGS_REQD_MASK = 0x00f0;
/** Possible values. Configured values will be rounded down. */
private static final int[] TAGS_REQD = {
0, 2, 3, 6, 9, 14, 20, 27,
35, 45, 57, 72, 92, 117, 147, 192
};
/** default true */
public void setSendLeaseSet(boolean yes) {
@ -76,19 +69,19 @@ public class SendMessageOptions extends DateAndFlags {
/**
* If we are low on tags, send this many.
* Power of 2 recommended - rounds down.
* default 0, meaning unset
* default 0, meaning unset, use the SKM config (default 40)
* @param tags 0 or 2 to 128
*/
public void setTagsToSend(int tags) {
if (tags < 0)
throw new IllegalArgumentException();
_flags &= ~TAGS_SEND_MASK;
_flags |= linToExp(Math.min(tags, MAX_SEND_TAGS) / 2) << 1;
_flags |= valToCode(tags, TAGS_SEND);
}
/**
* If we are low on tags, send this many.
* @return default 0, meaning unset
* @return default 0, meaning unset, use the SKM config (default 40)
*/
public int getTagsToSend() {
return getTagsToSend(_flags);
@ -96,29 +89,29 @@ public class SendMessageOptions extends DateAndFlags {
/**
* If we are low on tags, send this many.
* @return default 0, meaning unset
* @return default 0, meaning unset, use the SKM config (default 40)
*/
public static int getTagsToSend(int flags) {
int exp = (flags & TAGS_SEND_MASK) >> 1;
return 2 * expToLin(exp);
int exp = (flags & TAGS_SEND_MASK);
return codeToVal(exp, TAGS_SEND);
}
/**
* Low tag threshold. If less than this many, send more.
* Power of 2 recommended - rounds down.
* default 0, meaning unset
* @param tags 0 to 64
* default 0, meaning unset, use the SKM config (default 30)
* @param tags 0 to 90
*/
public void setTagThreshold(int tags) {
if (tags < 0)
throw new IllegalArgumentException();
_flags &= ~TAGS_REQD_MASK;
_flags |= linToExp(Math.min(tags, MAX_REQD_TAGS)) << 4;
_flags |= valToCode(tags, TAGS_REQD) << 4;
}
/**
* Low tag threshold. If less than this many, send more.
* @return default 0, meaning unset
* @return default 0, meaning unset, use the SKM config (default 30)
*/
public int getTagThreshold() {
return getTagThreshold(_flags);
@ -126,26 +119,26 @@ public class SendMessageOptions extends DateAndFlags {
/**
* Low tag threshold. If less than this many, send more.
* @return default 0, meaning unset
* @return default 0, meaning unset, use the SKM config (default 30)
*/
public static int getTagThreshold(int flags) {
int exp = (flags & TAGS_REQD_MASK) >> 4;
return expToLin(exp);
return codeToVal(exp, TAGS_REQD);
}
/** rounds down */
private static int linToExp(int lin) {
int exp = 0;
while (lin > 0) {
exp++;
lin >>= 1;
private static int valToCode(int val, int[] codes) {
// special case, round up so we don't turn it into default
if (val > 0 && val <= codes[1])
return 1;
for (int i = 1; i < codes.length; i++) {
if (val < codes[i])
return i - 1;
}
return exp;
return codes.length - 1;
}
private static int expToLin(int exp) {
if (exp <= 0)
return 0;
return 1 << (exp - 1);
private static int codeToVal(int code, int[] codes) {
return codes[code];
}
}

4
core/java/src/net/i2p/crypto/ElGamalAESEngine.java
View File

@ -38,6 +38,8 @@ public class ElGamalAESEngine {
private final Log _log;
private final static int MIN_ENCRYPTED_SIZE = 80; // smallest possible resulting size
private final I2PAppContext _context;
/** enforced since release 0.6 */
public static final int MAX_TAGS_RECEIVED = 200;
public ElGamalAESEngine(I2PAppContext ctx) {
_context = ctx;
@ -328,7 +330,7 @@ public class ElGamalAESEngine {
//ByteArrayInputStream bais = new ByteArrayInputStream(decrypted);
int cur = 0;
long numTags = DataHelper.fromLong(decrypted, cur, 2);
if ((numTags < 0) || (numTags > 200)) throw new Exception("Invalid number of session tags");
if ((numTags < 0) || (numTags > MAX_TAGS_RECEIVED)) throw new Exception("Invalid number of session tags");
if (numTags > 0) tags = new ArrayList((int)numTags);
cur += 2;
//_log.debug("# tags: " + numTags);