Messages in this thread Patch in this message | | | Date | Wed, 14 Dec 2005 09:31:33 -0400 | From | Anderson Briglia <> | Subject | [patch 2/5] [RFC] Add MMC password protection (lock/unlock) support |
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Implement card lock/unlock card operation, using the MMC_LOCK_UNLOCK command.
Signed-off-by: Anderson Briglia <anderson.briglia@indt.org.br> Signed-off-by: Anderson Lizardo <anderson.lizardo@indt.org.br> Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar@indt.org.br>
Index: linux-2.6.14-omap2/drivers/mmc/mmc.c =================================================================== --- linux-2.6.14-omap2.orig/drivers/mmc/mmc.c 2005-12-13 11:41:08.000000000 -0400 +++ linux-2.6.14-omap2/drivers/mmc/mmc.c 2005-12-13 14:49:12.000000000 -0400 @@ -4,6 +4,8 @@ * Copyright (C) 2003-2004 Russell King, All Rights Reserved. * SD support Copyright (C) 2004 Ian Molton, All Rights Reserved. * SD support Copyright (C) 2005 Pierre Ossman, All Rights Reserved. + * MMC password protection (C) 2005 Instituto Nokia de Tecnologia (INdT), + * All Rights Reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -20,6 +22,7 @@ #include <linux/err.h> #include <asm/scatterlist.h> #include <linux/scatterlist.h> +#include <linux/key.h> #include <linux/mmc/card.h> #include <linux/mmc/host.h> @@ -1088,6 +1091,159 @@ static void mmc_setup(struct mmc_host *h mmc_read_scrs(host); } +static int pop(unsigned x) +{ + x = x - ((x >> 1) & 0x55555555); + x = (x & 0x33333333) + ((x >> 2) & 0x33333333); + x = (x + (x >> 4)) & 0x0F0F0F0F; + x = x + (x >> 8); + x = x + (x >> 16); + + return x & 0x0000003F; +} + +static int ilog2(unsigned x) +{ + x = x | (x >> 1); + x = x | (x >> 2); + x = x | (x >> 4); + x = x | (x >> 8); + x = x | (x >> 16); + + return pop(x) - 1; +} + +/* Calculate the minimal blksz_bits to hold x bytes. The two math functions + * above are used to do the calculation. + * + * XXX There must be a simpler way to do this... */ +static inline int blksz_bits(unsigned x) +{ + return 1 + ilog2(x - 1); +} + +/** + * mmc_lock_unlock - send LOCK_UNLOCK command to a specific card. + * @card: card to which the LOCK_UNLOCK command should be sent + * @key: key containing the MMC password + * @mode: LOCK_UNLOCK mode + * + */ +int mmc_lock_unlock(struct mmc_card *card, struct key *key, int mode) +{ + struct mmc_request mrq; + struct mmc_command cmd; + struct mmc_data data; + struct scatterlist sg; + struct mmc_key_payload *mpayload; + unsigned long erase_timeout; + int err, data_size; + u8 *data_buf; + + mpayload = NULL; + data_size = 1; + if (mode != MMC_LOCK_MODE_ERASE) { + mpayload = rcu_dereference(key->payload.data); + data_size = 2 + mpayload->datalen; + } + + data_buf = kmalloc(data_size, GFP_KERNEL); + if (!data_buf) + return -ENOMEM; + memset(data_buf, 0, data_size); + + data_buf[0] = mode; + if (mode != MMC_LOCK_MODE_ERASE) { + data_buf[1] = mpayload->datalen; + memcpy(data_buf + 2, mpayload->data, mpayload->datalen); + } + + err = mmc_card_claim_host(card); + if (err != MMC_ERR_NONE) { + mmc_card_set_dead(card); + goto out; + } + + memset(&cmd, 0, sizeof(struct mmc_command)); + + cmd.opcode = MMC_SET_BLOCKLEN; + cmd.arg = data_size; + cmd.flags = MMC_RSP_R1; + err = mmc_wait_for_cmd(card->host, &cmd, CMD_RETRIES); + if (err != MMC_ERR_NONE) { + mmc_card_set_dead(card); + goto error; + } + + memset(&cmd, 0, sizeof(struct mmc_command)); + + cmd.opcode = MMC_LOCK_UNLOCK; + cmd.arg = 0; + cmd.flags = MMC_RSP_R1B; + + memset(&data, 0, sizeof(struct mmc_data)); + + data.timeout_ns = card->csd.tacc_ns * 10; + data.timeout_clks = card->csd.tacc_clks * 10; + data.blksz_bits = blksz_bits(data_size); + data.blocks = 1; + data.flags = MMC_DATA_WRITE; + data.sg = &sg; + data.sg_len = 1; + + memset(&mrq, 0, sizeof(struct mmc_request)); + + mrq.cmd = &cmd; + mrq.data = &data; + + sg_init_one(&sg, data_buf, data_size); + err = mmc_wait_for_req(card->host, &mrq); + if (err != MMC_ERR_NONE) { + mmc_card_set_dead(card); + goto error; + } + + memset(&cmd, 0, sizeof(struct mmc_command)); + + cmd.opcode = MMC_SEND_STATUS; + cmd.arg = card->rca << 16; + cmd.flags = MMC_RSP_R1; + + /* set timeout for forced erase operation to 3 min. (see MMC spec) */ + erase_timeout = jiffies + 180 * HZ; + do { + /* we cannot use "retries" here because the + * R1_LOCK_UNLOCK_FAILED bit is cleared by subsequent reads to + * the status register, hiding the error condition */ + err = mmc_wait_for_cmd(card->host, &cmd, 0); + if (err != MMC_ERR_NONE) + break; + /* the other modes don't need timeout checking */ + if (mode != MMC_LOCK_MODE_ERASE) + continue; + if (time_after(jiffies, erase_timeout)) { + dev_dbg(&card->dev, "forced erase timed out\n"); + err = MMC_ERR_TIMEOUT; + break; + } + } while (!(cmd.resp[0] & R1_READY_FOR_DATA)); + if (cmd.resp[0] & R1_LOCK_UNLOCK_FAILED) { + dev_dbg(&card->dev, "LOCK_UNLOCK operation failed\n"); + err = MMC_ERR_FAILED; + } + +error: + mmc_check_cards(card->host); + mmc_deselect_cards(card->host); + mmc_card_release_host(card); +out: + kfree(data_buf); + + return err; +} + +EXPORT_SYMBOL(mmc_lock_unlock); + /** * mmc_detect_change - process change of state on a MMC socket Index: linux-2.6.14-omap2/include/linux/mmc/card.h =================================================================== --- linux-2.6.14-omap2.orig/include/linux/mmc/card.h 2005-12-13 11:41:08.000000000 -0400 +++ linux-2.6.14-omap2/include/linux/mmc/card.h 2005-12-13 11:42:06.000000000 -0400 @@ -10,6 +10,7 @@ #ifndef LINUX_MMC_CARD_H #define LINUX_MMC_CARD_H +#include <linux/key.h> #include <linux/mmc/mmc.h> struct mmc_cid { @@ -109,4 +110,6 @@ static inline int mmc_card_claim_host(st #define mmc_card_release_host(c) mmc_release_host((c)->host) +extern int mmc_lock_unlock(struct mmc_card *card, struct key *key, int mode); + #endif Index: linux-2.6.14-omap2/include/linux/mmc/protocol.h =================================================================== --- linux-2.6.14-omap2.orig/include/linux/mmc/protocol.h 2005-12-13 11:41:01.000000000 -0400 +++ linux-2.6.14-omap2/include/linux/mmc/protocol.h 2005-12-13 11:42:21.000000000 -0400 @@ -243,5 +243,13 @@ struct _mmc_csd { #define SD_BUS_WIDTH_1 0 #define SD_BUS_WIDTH_4 2 +/* + * MMC_LOCK_UNLOCK modes + */ +#define MMC_LOCK_MODE_ERASE (1<<3) +#define MMC_LOCK_MODE_UNLOCK (0<<2) +#define MMC_LOCK_MODE_CLR_PWD (1<<1) +#define MMC_LOCK_MODE_SET_PWD (1<<0) + #endif /* MMC_MMC_PROTOCOL_H */ -- Anderson Briglia, Anderson Lizardo, Carlos Eduardo Aguiar
Embedded Linux Lab - 10LE Nokia Institute of Technology - INdT Manaus - Brazil
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