Ping.... Is there anyone looking at this potential bug?? -----Original Message----- From: Chaoxing Lin Sent: Friday, March 08, 2013 11:38 AM To: 'linux-crypto@xxxxxxxxxxxxxxx' Subject: potential bug in GMAC implementation. not work in ESN mode I was testing ipsec with GMAC and found that the rfc4543 GMAC implementation in kernel software crypto work in "esp=aes256gmac-noesn!" mode. It does not work in in "esp=aes256gmac-esn!" mode. The tunnel was established but no data traffic is possible. Looking at source code, I found this piece of code is suspicious. Line 1146~1147 tries to put req->assoc to assoc[1]. But I think this way only works when req->assoc has only one segment. In ESN mode, req->assoc contains 3 segments (SPI, SN-hi, SN-low). Line 1146~1147 will only attach SPI segment(with total length) in assoc. Please let me know whether I understand it right. Thanks, Chaoxing Source from kernel 3.8.2 path: root/crypto/gcm.c 1136: /* construct the aad */ 1137: dstp = sg_page(dst); vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset; sg_init_table(payload, 2); sg_set_buf(payload, req->iv, 8); scatterwalk_crypto_chain(payload, dst, vdst == req->iv + 8, 2); assoclen += 8 + req->cryptlen - (enc ? 0 : authsize); sg_init_table(assoc, 2); 1146: sg_set_page(assoc, sg_page(req->assoc), req->assoc->length, 1147: req->assoc->offset); scatterwalk_crypto_chain(assoc, payload, 0, 2); aead_request_set_tfm(subreq, ctx->child); aead_request_set_callback(subreq, req->base.flags, req->base.complete, req->base.data); aead_request_set_crypt(subreq, cipher, cipher, enc ? 0 : authsize, iv); 1154: aead_request_set_assoc(subreq, assoc, assoclen); -- 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
