diff options
author | Ralph Wuerthner <rwuerthn@de.ibm.com> | 2008-04-17 07:46:15 +0200 |
---|---|---|
committer | Heiko Carstens <heiko.carstens@de.ibm.com> | 2008-04-17 07:47:02 +0200 |
commit | 2f7c8bd6dc6540aa3275c0ad9f657401985c00e9 (patch) | |
tree | 12cb12d661424d332ad960113c8849b3579e7e6a /drivers/s390/crypto/zcrypt_pcixcc.c | |
parent | 893f11286644780fc7d6d415e537644da7bdaaf8 (diff) |
[S390] zcrypt: add support for large random numbers
This patch allows user space applications to access large amounts of
truly random data. The random data source is the build-in hardware
random number generator on the CEX2C cards.
Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Diffstat (limited to 'drivers/s390/crypto/zcrypt_pcixcc.c')
-rw-r--r-- | drivers/s390/crypto/zcrypt_pcixcc.c | 199 |
1 files changed, 198 insertions, 1 deletions
diff --git a/drivers/s390/crypto/zcrypt_pcixcc.c b/drivers/s390/crypto/zcrypt_pcixcc.c index 70b9ddc8cf9d..3674bfa82b65 100644 --- a/drivers/s390/crypto/zcrypt_pcixcc.c +++ b/drivers/s390/crypto/zcrypt_pcixcc.c @@ -356,6 +356,55 @@ static int XCRB_msg_to_type6CPRB_msgX(struct zcrypt_device *zdev, } /** + * Prepare a type6 CPRB message for random number generation + * + * @ap_dev: AP device pointer + * @ap_msg: pointer to AP message + */ +static void rng_type6CPRB_msgX(struct ap_device *ap_dev, + struct ap_message *ap_msg, + unsigned random_number_length) +{ + struct { + struct type6_hdr hdr; + struct CPRBX cprbx; + char function_code[2]; + short int rule_length; + char rule[8]; + short int verb_length; + short int key_length; + } __attribute__((packed)) *msg = ap_msg->message; + static struct type6_hdr static_type6_hdrX = { + .type = 0x06, + .offset1 = 0x00000058, + .agent_id = {'C', 'A'}, + .function_code = {'R', 'L'}, + .ToCardLen1 = sizeof *msg - sizeof(msg->hdr), + .FromCardLen1 = sizeof *msg - sizeof(msg->hdr), + }; + static struct CPRBX static_cprbx = { + .cprb_len = 0x00dc, + .cprb_ver_id = 0x02, + .func_id = {0x54, 0x32}, + .req_parml = sizeof *msg - sizeof(msg->hdr) - + sizeof(msg->cprbx), + .rpl_msgbl = sizeof *msg - sizeof(msg->hdr), + }; + + msg->hdr = static_type6_hdrX; + msg->hdr.FromCardLen2 = random_number_length, + msg->cprbx = static_cprbx; + msg->cprbx.rpl_datal = random_number_length, + msg->cprbx.domain = AP_QID_QUEUE(ap_dev->qid); + memcpy(msg->function_code, msg->hdr.function_code, 0x02); + msg->rule_length = 0x0a; + memcpy(msg->rule, "RANDOM ", 8); + msg->verb_length = 0x02; + msg->key_length = 0x02; + ap_msg->length = sizeof *msg; +} + +/** * Copy results from a type 86 ICA reply message back to user space. * * @zdev: crypto device pointer @@ -509,6 +558,26 @@ static int convert_type86_xcrb(struct zcrypt_device *zdev, return 0; } +static int convert_type86_rng(struct zcrypt_device *zdev, + struct ap_message *reply, + char *buffer) +{ + struct { + struct type86_hdr hdr; + struct type86_fmt2_ext fmt2; + struct CPRBX cprbx; + } __attribute__((packed)) *msg = reply->message; + char *data = reply->message; + + if (msg->cprbx.ccp_rtcode != 0 || msg->cprbx.ccp_rscode != 0) { + PDEBUG("RNG response error on PCIXCC/CEX2C rc=%hu/rs=%hu\n", + rc, rs); + return -EINVAL; + } + memcpy(buffer, data + msg->fmt2.offset2, msg->fmt2.count2); + return msg->fmt2.count2; +} + static int convert_response_ica(struct zcrypt_device *zdev, struct ap_message *reply, char __user *outputdata, @@ -567,6 +636,31 @@ static int convert_response_xcrb(struct zcrypt_device *zdev, } } +static int convert_response_rng(struct zcrypt_device *zdev, + struct ap_message *reply, + char *data) +{ + struct type86x_reply *msg = reply->message; + + switch (msg->hdr.type) { + case TYPE82_RSP_CODE: + case TYPE88_RSP_CODE: + return -EINVAL; + case TYPE86_RSP_CODE: + if (msg->hdr.reply_code) + return -EINVAL; + if (msg->cprbx.cprb_ver_id == 0x02) + return convert_type86_rng(zdev, reply, data); + /* no break, incorrect cprb version is an unknown response */ + default: /* Unknown response type, this should NEVER EVER happen */ + PRINTK("Unrecognized Message Header: %08x%08x\n", + *(unsigned int *) reply->message, + *(unsigned int *) (reply->message+4)); + zdev->online = 0; + return -EAGAIN; /* repeat the request on a different device. */ + } +} + /** * This function is called from the AP bus code after a crypto request * "msg" has finished with the reply message "reply". @@ -736,6 +830,42 @@ out_free: } /** + * The request distributor calls this function if it picked the PCIXCC/CEX2C + * device to generate random data. + * @zdev: pointer to zcrypt_device structure that identifies the + * PCIXCC/CEX2C device to the request distributor + * @buffer: pointer to a memory page to return random data + */ + +static long zcrypt_pcixcc_rng(struct zcrypt_device *zdev, + char *buffer) +{ + struct ap_message ap_msg; + struct response_type resp_type = { + .type = PCIXCC_RESPONSE_TYPE_XCRB, + }; + int rc; + + ap_msg.message = kmalloc(PCIXCC_MAX_XCRB_MESSAGE_SIZE, GFP_KERNEL); + if (!ap_msg.message) + return -ENOMEM; + ap_msg.psmid = (((unsigned long long) current->pid) << 32) + + atomic_inc_return(&zcrypt_step); + ap_msg.private = &resp_type; + rng_type6CPRB_msgX(zdev->ap_dev, &ap_msg, ZCRYPT_RNG_BUFFER_SIZE); + init_completion(&resp_type.work); + ap_queue_message(zdev->ap_dev, &ap_msg); + rc = wait_for_completion_interruptible(&resp_type.work); + if (rc == 0) + rc = convert_response_rng(zdev, &ap_msg, buffer); + else + /* Signal pending. */ + ap_cancel_message(zdev->ap_dev, &ap_msg); + kfree(ap_msg.message); + return rc; +} + +/** * The crypto operations for a PCIXCC/CEX2C card. */ static struct zcrypt_ops zcrypt_pcixcc_ops = { @@ -744,6 +874,13 @@ static struct zcrypt_ops zcrypt_pcixcc_ops = { .send_cprb = zcrypt_pcixcc_send_cprb, }; +static struct zcrypt_ops zcrypt_pcixcc_with_rng_ops = { + .rsa_modexpo = zcrypt_pcixcc_modexpo, + .rsa_modexpo_crt = zcrypt_pcixcc_modexpo_crt, + .send_cprb = zcrypt_pcixcc_send_cprb, + .rng = zcrypt_pcixcc_rng, +}; + /** * Micro-code detection function. Its sends a message to a pcixcc card * to find out the microcode level. @@ -859,6 +996,58 @@ out_free: } /** + * Large random number detection function. Its sends a message to a pcixcc + * card to find out if large random numbers are supported. + * @ap_dev: pointer to the AP device. + * + * Returns 1 if large random numbers are supported, 0 if not and < 0 on error. + */ +static int zcrypt_pcixcc_rng_supported(struct ap_device *ap_dev) +{ + struct ap_message ap_msg; + unsigned long long psmid; + struct { + struct type86_hdr hdr; + struct type86_fmt2_ext fmt2; + struct CPRBX cprbx; + } __attribute__((packed)) *reply; + int rc, i; + + ap_msg.message = (void *) get_zeroed_page(GFP_KERNEL); + if (!ap_msg.message) + return -ENOMEM; + + rng_type6CPRB_msgX(ap_dev, &ap_msg, 4); + rc = ap_send(ap_dev->qid, 0x0102030405060708ULL, ap_msg.message, + ap_msg.length); + if (rc) + goto out_free; + + /* Wait for the test message to complete. */ + for (i = 0; i < 2 * HZ; i++) { + msleep(1000 / HZ); + rc = ap_recv(ap_dev->qid, &psmid, ap_msg.message, 4096); + if (rc == 0 && psmid == 0x0102030405060708ULL) + break; + } + + if (i >= 2 * HZ) { + /* Got no answer. */ + rc = -ENODEV; + goto out_free; + } + + reply = ap_msg.message; + if (reply->cprbx.ccp_rtcode == 0 && reply->cprbx.ccp_rscode == 0) + rc = 1; + else + rc = 0; +out_free: + free_page((unsigned long) ap_msg.message); + return rc; +} + +/** * Probe function for PCIXCC/CEX2C cards. It always accepts the AP device * since the bus_match already checked the hardware type. The PCIXCC * cards come in two flavours: micro code level 2 and micro code level 3. @@ -874,7 +1063,6 @@ static int zcrypt_pcixcc_probe(struct ap_device *ap_dev) if (!zdev) return -ENOMEM; zdev->ap_dev = ap_dev; - zdev->ops = &zcrypt_pcixcc_ops; zdev->online = 1; if (ap_dev->device_type == AP_DEVICE_TYPE_PCIXCC) { rc = zcrypt_pcixcc_mcl(ap_dev); @@ -901,6 +1089,15 @@ static int zcrypt_pcixcc_probe(struct ap_device *ap_dev) zdev->min_mod_size = PCIXCC_MIN_MOD_SIZE; zdev->max_mod_size = PCIXCC_MAX_MOD_SIZE; } + rc = zcrypt_pcixcc_rng_supported(ap_dev); + if (rc < 0) { + zcrypt_device_free(zdev); + return rc; + } + if (rc) + zdev->ops = &zcrypt_pcixcc_with_rng_ops; + else + zdev->ops = &zcrypt_pcixcc_ops; ap_dev->reply = &zdev->reply; ap_dev->private = zdev; rc = zcrypt_device_register(zdev); |