Hi , I am trying to analyze Linux Kernel Crypto Interface with respective to hashing(ahash for SHA1 in particular) . I am looking at omap-sham.c/atmel-sha.c as reference,which is in open source linux/driver/crypto.I need some inputs in understanding following . #1: If It need to handle a scenario where in which multiple messages will be given to generate a digest/Hash message like below. Ex: Input Block = buffer1 + buffer2 +.... +buffern if I need to generate hash for Input Block(could be anything like a fwimage/file etc) , Then I ll split it into some buffers and I ll send it in chunks like buffer1,bffer2 etc to underlying crypto driver Hash( Input Block) = Hash(buffer1) + Hash(buffer2) + ..... + Hash( buffern) | | + ..... + | | | | sha_update(*) sha_update(*) sha_update(*) How is it possible to keep track/store intermediate Hash generated data like for buffer1,buffer2 etc ? #2: what is the need to have multiple structures like "*_sha_reqctx " and "*_sha_dev" ? As Per my understanding "*_sha_reqctx" structure is for generic Linux Kernel Crypto crypto context to interact with specific crypto request and "*_sha_dev" structure is for Hardware specific some thing like for any DMA related operations. BR, Srisowj -- 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