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for applet to be trusted. it HAS TO BE Digitally signed. unsigned applet is NOT TRUSTED if a signed jar is modified, it can be verified..but verification process will fail ..data integreity check is done by public/private key algo
Joined: Jun 20, 2003
What do you mean "verification process will fail"? Do you mean if I use "jarsigner -verify a.jar", some failure infomation will appear?
Joined: Jun 09, 2003
For example, if someone has exploded a signed JAR file, has modified one of its files, and has rebuilt the JAR file, when we try to verify the signature using jarsigner, we get the following error message:
Originally posted by sowmya thiru: For example, if someone has exploded a signed JAR file, has modified one of its files, and has rebuilt the JAR file, when we try to verify the signature using jarsigner, we get the following error message:
jarsigner: java.lang.SecurityException: SHA1 digest error for itso.class
That's true. But if I ADD or DELETE files in the JAR, the verification still succeeds.
But if I ADD or DELETE files in the JAR, the verification still succeeds.
I believe the signature is on a per-file bases (files in the Jar). Any files that are unchanged after signing the JAR should still verify successfully even if other files were added or deleted. The added files would not verify unless the Jar is signed again after the Add. (I'm too lazy to try this out, however.
Juan Rolando Prieur-Reza, M.S., LSSBB, SCEA, SCBCD, SCWCD, SCJP/1.6, IBM OOAD, SCSA