Hello Stephan Thank you for your fast answer My idea is to do zero copy encryption and the cipher I am using is authenc(hmac(sha1),cbc(aes). The layout of my buffer is espHeader(AD) || IV || plaintext || Integrity (TAG) As I see it, the SGs do point to the same buffer, but they do not overlap Below, some parts of my code // Prepare data sg_init_table(sg,ARRAY_SIZE(sg)); sg_set_buf(&sg[1],cipherText_p,espHdrLen); sg_set_buf(&sg[0],cipherText_p+espHdrLen+ivLen,plen+intLen); // Put plaintext in cipherText + espHdr + ivLen // put esp header info in ciphertext req_p = aead_givcrypt_alloc(aead_p,GFP_KERNEL); aead_givcrypt_set_callback(req_p,0,hwencpoc_testCipher_cb,cipherText_p); aead_givcrypt_set_crypt(req_p,&sg[0],&sg[0],plen,iv_p); aead_givcrypt_set_assoc(req_p,&sg[1],espHdrLen); aead_givcrypt_set_giv(req_p,cipherText_p+espHdrLen,0); ret=crypto_aead_givencrypt(req_p); However, when I get the callback, the associated data has been overwritten (first 8 bytes of the cipherText buffer), and the integrity is wrong. The IV and the encryption are correct. What I am doing wrong? Thank you again Juan 2016-10-26 18:32 GMT+02:00 Stephan Mueller <smueller@xxxxxxxxxx>: > Am Mittwoch, 26. Oktober 2016, 18:17:14 CEST schrieb Juan Pablo Nariño > Mendoza: > > Hi Juan, > >> Sorry in advance for making what shall be a basic question for this >> list, but I have really ran out of ideas. >> >> Can someone explain me please, how does the memory layout and sg lists >> work for the IPSec case, with generated IV case? >> >> As I understand, it is like this (ascii art) >> >> AD | IV Space | Plain Text | Auth Tag >> ^ ^ >> >> asg sg > > The memory layout is correct when using the RFC4106 cipher. > > How you partition your physical memory with the SGL is your choice as long as > your data in the SGL is lined up as you mentioned above. >> >> But I am having the AD overwritten, and the AUTH tag and encryption is >> not correct? Could someone please point me in the right direction? >> Thank you again > > Maybe the src and dst SGL somehow partially overlap? >> >> Regards >> >> Juan >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-crypto" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > > Ciao > Stephan -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
