diff --git a/drivers/s390/crypto/zcrypt_ccamisc.c b/drivers/s390/crypto/zcrypt_ccamisc.c index 86d2ee7..d4ce635 100644 --- a/drivers/s390/crypto/zcrypt_ccamisc.c +++ b/drivers/s390/crypto/zcrypt_ccamisc.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -267,6 +268,10 @@ EXPORT_SYMBOL(cca_check_sececckeytoken); * block, reply CPRB and reply param block and fill in values * for the common fields. Returns 0 on success or errno value * on failure. + * It is guaranteed that request and a possible param block + * are aligned to a 4 byte boundary. Furthermore if a param + * block is used, the memory allocated for this is rounded up to + * the next multiple of 4 bytes. */ static int alloc_and_prep_cprbmem(size_t paramblen, u8 **p_cprb_mem, @@ -275,7 +280,8 @@ static int alloc_and_prep_cprbmem(size_t paramblen, u32 xflags) { u8 *cprbmem = NULL; - size_t cprbplusparamblen = sizeof(struct CPRBX) + paramblen; + size_t cprbplusparamblen = + ALIGN(sizeof(struct CPRBX), 4) + ALIGN(paramblen, 4); size_t len = 2 * cprbplusparamblen; struct CPRBX *preqcblk, *prepcblk; @@ -302,10 +308,10 @@ static int alloc_and_prep_cprbmem(size_t paramblen, memcpy(preqcblk->func_id, "T2", 2); preqcblk->rpl_msgbl = cprbplusparamblen; if (paramblen) { - preqcblk->req_parmb = - ((u8 __user *)preqcblk) + sizeof(struct CPRBX); - preqcblk->rpl_parmb = - ((u8 __user *)prepcblk) + sizeof(struct CPRBX); + preqcblk->req_parmb = ((u8 __user *)preqcblk) + + ALIGN(sizeof(struct CPRBX), 4); + preqcblk->rpl_parmb = ((u8 __user *)prepcblk) + + ALIGN(sizeof(struct CPRBX), 4); } *p_cprb_mem = cprbmem; @@ -323,8 +329,10 @@ static int alloc_and_prep_cprbmem(size_t paramblen, */ static void free_cprbmem(void *mem, size_t paramblen, bool scrub, u32 xflags) { + size_t cprblen = ALIGN(sizeof(struct CPRBX), 4) + ALIGN(paramblen, 4); + if (mem && scrub) - memzero_explicit(mem, 2 * (sizeof(struct CPRBX) + paramblen)); + memzero_explicit(mem, 2 * cprblen); if (xflags & ZCRYPT_XFLAG_NOMEMALLOC) mempool_free(mem, cprb_mempool); diff --git a/drivers/s390/crypto/zcrypt_ep11misc.c b/drivers/s390/crypto/zcrypt_ep11misc.c index 3dda958..2d900ff 100644 --- a/drivers/s390/crypto/zcrypt_ep11misc.c +++ b/drivers/s390/crypto/zcrypt_ep11misc.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -355,21 +356,24 @@ EXPORT_SYMBOL(ep11_check_aes_key); /* * Allocate and prepare ep11 cprb plus additional payload. + * It is guaranteed that the memory is aligned to a 4 byte boundary. + * Furthermore the memory allocation is rounded up to the next + * multiple of 4 bytes (with taking the payload_len into account). */ static void *alloc_cprbmem(size_t payload_len, u32 xflags) { - size_t len = sizeof(struct ep11_cprb) + payload_len; + size_t memlen = ALIGN(sizeof(struct ep11_cprb) + payload_len, 4); struct ep11_cprb *cprb = NULL; if (xflags & ZCRYPT_XFLAG_NOMEMALLOC) { - if (len <= CPRB_MEMPOOL_ITEM_SIZE) + if (memlen <= CPRB_MEMPOOL_ITEM_SIZE) cprb = mempool_alloc_preallocated(cprb_mempool); } else { - cprb = kmalloc(len, GFP_KERNEL); + cprb = kmalloc(memlen, GFP_KERNEL); } if (!cprb) return NULL; - memset(cprb, 0, len); + memset(cprb, 0, memlen); cprb->cprb_len = sizeof(struct ep11_cprb); cprb->cprb_ver_id = 0x04; @@ -385,8 +389,10 @@ static void *alloc_cprbmem(size_t payload_len, u32 xflags) */ static void free_cprbmem(void *mem, size_t payload_len, bool scrub, u32 xflags) { + size_t memlen = ALIGN(sizeof(struct ep11_cprb) + payload_len, 4); + if (mem && scrub) - memzero_explicit(mem, sizeof(struct ep11_cprb) + payload_len); + memzero_explicit(mem, memlen); if (xflags & ZCRYPT_XFLAG_NOMEMALLOC) mempool_free(mem, cprb_mempool); diff --git a/drivers/s390/crypto/zcrypt_msgtype6.c b/drivers/s390/crypto/zcrypt_msgtype6.c index 40f72cd..3df1d67 100644 --- a/drivers/s390/crypto/zcrypt_msgtype6.c +++ b/drivers/s390/crypto/zcrypt_msgtype6.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "ap_bus.h" #include "zcrypt_api.h" @@ -34,6 +35,9 @@ #define CEXXC_RESPONSE_TYPE_XCRB 1 #define CEXXC_RESPONSE_TYPE_EP11 2 +/* smallest possible EP11 payload size */ +#define MIN_EP11_PAYLOAD_SIZE 5 + MODULE_AUTHOR("IBM Corporation"); MODULE_DESCRIPTION("Cryptographic Coprocessor (message type 6), " \ "Copyright IBM Corp. 2001, 2023"); @@ -342,49 +346,39 @@ static int xcrb_msg_to_type6cprb_msgx(bool userspace, struct ap_message *ap_msg, }; } __packed * msg = ap_msg->msg; - int rcblen = CEIL4(xcrb->request_control_blk_length); - int req_sumlen, resp_sumlen; - char *req_data = ap_msg->msg + sizeof(struct type6_hdr) + rcblen; - char *function_code; - - if (CEIL4(xcrb->request_control_blk_length) < - xcrb->request_control_blk_length) - return -EINVAL; /* overflow after alignment*/ + size_t req_cblen, rep_cblen, req_sumlen, rep_sumlen; + char *function_code, *req_data; - /* length checks */ - ap_msg->len = sizeof(struct type6_hdr) + - CEIL4(xcrb->request_control_blk_length) + - xcrb->request_data_length; + /* request length and overflow checks */ + if (xcrb->request_control_blk_length < sizeof(struct CPRBX)) + return -EINVAL; + req_cblen = CEIL4((size_t)xcrb->request_control_blk_length); + if (req_cblen > U32_MAX) + return -EINVAL; + req_sumlen = req_cblen + xcrb->request_data_length; + if (req_sumlen > U32_MAX) + return -EINVAL; + ap_msg->len = sizeof(struct type6_hdr) + req_sumlen; if (ap_msg->len > ap_msg->bufsize) return -EINVAL; - - /* - * Overflow check - * sum must be greater (or equal) than the largest operand - */ - req_sumlen = CEIL4(xcrb->request_control_blk_length) + - xcrb->request_data_length; - if ((CEIL4(xcrb->request_control_blk_length) <= - xcrb->request_data_length) ? + if (req_cblen <= xcrb->request_data_length ? req_sumlen < xcrb->request_data_length : - req_sumlen < CEIL4(xcrb->request_control_blk_length)) { + req_sumlen < req_cblen) { return -EINVAL; } - if (CEIL4(xcrb->reply_control_blk_length) < - xcrb->reply_control_blk_length) - return -EINVAL; /* overflow after alignment*/ - - /* - * Overflow check - * sum must be greater (or equal) than the largest operand - */ - resp_sumlen = CEIL4(xcrb->reply_control_blk_length) + - xcrb->reply_data_length; - if ((CEIL4(xcrb->reply_control_blk_length) <= - xcrb->reply_data_length) ? - resp_sumlen < xcrb->reply_data_length : - resp_sumlen < CEIL4(xcrb->reply_control_blk_length)) { + /* reply length and overflow checks */ + if (xcrb->reply_control_blk_length < sizeof(struct CPRBX)) + return -EINVAL; + rep_cblen = CEIL4((size_t)xcrb->reply_control_blk_length); + if (rep_cblen > U32_MAX) + return -EINVAL; + rep_sumlen = rep_cblen + xcrb->reply_data_length; + if (rep_sumlen > U32_MAX) + return -EINVAL; + if (rep_cblen <= xcrb->reply_data_length ? + rep_sumlen < xcrb->reply_data_length : + rep_sumlen < rep_cblen) { return -EINVAL; } @@ -393,7 +387,7 @@ static int xcrb_msg_to_type6cprb_msgx(bool userspace, struct ap_message *ap_msg, memcpy(msg->hdr.agent_id, &xcrb->agent_ID, sizeof(xcrb->agent_ID)); msg->hdr.tocardlen1 = xcrb->request_control_blk_length; if (xcrb->request_data_length) { - msg->hdr.offset2 = msg->hdr.offset1 + rcblen; + msg->hdr.offset2 = msg->hdr.offset1 + req_cblen; msg->hdr.tocardlen2 = xcrb->request_data_length; } msg->hdr.fromcardlen1 = xcrb->reply_control_blk_length; @@ -404,8 +398,12 @@ static int xcrb_msg_to_type6cprb_msgx(bool userspace, struct ap_message *ap_msg, xcrb->request_control_blk_addr, xcrb->request_control_blk_length)) return -EFAULT; - if (msg->cprbx.cprb_len + sizeof(msg->hdr.function_code) > - xcrb->request_control_blk_length) + /* pad tail with 0 up to req_cblen */ + if (xcrb->request_control_blk_length < req_cblen) + memset(msg->userdata + xcrb->request_control_blk_length, + 0, req_cblen - xcrb->request_control_blk_length); + /* copy subfunction code into AP msg type 6 function code field */ + if (msg->cprbx.cprb_len > req_cblen - sizeof(msg->hdr.function_code)) return -EINVAL; function_code = ((unsigned char *)&msg->cprbx) + msg->cprbx.cprb_len; memcpy(msg->hdr.function_code, function_code, @@ -437,20 +435,70 @@ static int xcrb_msg_to_type6cprb_msgx(bool userspace, struct ap_message *ap_msg, } /* copy data block */ - if (xcrb->request_data_length && - z_copy_from_user(userspace, req_data, xcrb->request_data_address, - xcrb->request_data_length)) - return -EFAULT; + if (xcrb->request_data_length) { + req_data = ap_msg->msg + sizeof(struct type6_hdr) + req_cblen; + if (z_copy_from_user(userspace, req_data, + xcrb->request_data_address, + xcrb->request_data_length)) + return -EFAULT; + } return 0; } +/* + * Simple asn1 int reader/decoder helper function + * Returns number of bytes processed or < 0 on failure + * Only accepts int length values of 1, 2 or 4. + */ +static inline int asn1_int_decode(const u8 *buf, size_t intlen, u32 *u) +{ + switch (intlen) { + case 1: + *u = (u32)(*buf); + return 1; + case 2: + *u = (u32)get_unaligned_be16(buf); + return 2; + case 4: + *u = (u32)get_unaligned_be32(buf); + return 4; + default: + return -EINVAL; + } +} + +/* + * Simple asn1 length parse helper function + * Returns number of bytes processed or < 0 on failure + * Only accepts length encoded within the length octet + * or for long form 1, 2 or 4 octet length bytes. + */ +static inline int asn1_length_decode(const u8 *buf, size_t buflen, u32 *u) +{ + int i; + + if (buflen < 1) + return -EINVAL; + + if (*buf < 128) { + *u = (u32)(*buf & 0x7F); + return 1; + } + + i = *buf & 0x7F; + if (--buflen < i) + return -EINVAL; + i = asn1_int_decode(++buf, i, u); + + return i < 0 ? i : i + 1; +} + static int xcrb_msg_to_type6_ep11cprb_msgx(bool userspace, struct ap_message *ap_msg, struct ep11_urb *xcrb, unsigned int *fcode, unsigned int *domain) { - unsigned int lfmt; static struct type6_hdr static_type6_ep11_hdr = { .type = 0x06, .rqid = {0x00, 0x01}, @@ -462,34 +510,32 @@ static int xcrb_msg_to_type6_ep11cprb_msgx(bool userspace, struct ap_message *ap struct { struct type6_hdr hdr; union { - struct { - struct ep11_cprb cprbx; - unsigned char pld_tag; /* fixed value 0x30 */ - unsigned char pld_lenfmt; /* length format */ - } __packed; + struct ep11_cprb cprbx; DECLARE_FLEX_ARRAY(u8, userdata); }; } __packed * msg = ap_msg->msg; - struct pld_hdr { - unsigned char func_tag; /* fixed value 0x4 */ - unsigned char func_len; /* fixed value 0x4 */ - unsigned int func_val; /* function ID */ - unsigned char dom_tag; /* fixed value 0x4 */ - unsigned char dom_len; /* fixed value 0x4 */ - unsigned int dom_val; /* domain id */ - } __packed * payload_hdr = NULL; + size_t req_len, rep_len, pld_len; + unsigned char *pld; + int offs = 0, i; + unsigned int u; - if (CEIL4(xcrb->req_len) < xcrb->req_len) - return -EINVAL; /* overflow after alignment*/ - - /* length checks */ - ap_msg->len = sizeof(struct type6_hdr) + CEIL4(xcrb->req_len); + /* request length and overflow checks */ + if (xcrb->req_len < sizeof(struct ep11_cprb) + MIN_EP11_PAYLOAD_SIZE) + return -EINVAL; + req_len = CEIL4(xcrb->req_len); + if (req_len < xcrb->req_len || req_len > U32_MAX) + return -EINVAL; + ap_msg->len = sizeof(struct type6_hdr) + req_len; if (ap_msg->len > ap_msg->bufsize) return -EINVAL; - if (CEIL4(xcrb->resp_len) < xcrb->resp_len) - return -EINVAL; /* overflow after alignment*/ + /* reply length and overflow checks */ + if (xcrb->resp_len < sizeof(struct ep11_cprb)) + return -EINVAL; + rep_len = CEIL4(xcrb->resp_len); + if (rep_len < xcrb->resp_len || rep_len > U32_MAX) + return -EINVAL; /* prepare type6 header */ msg->hdr = static_type6_ep11_hdr; @@ -498,26 +544,55 @@ static int xcrb_msg_to_type6_ep11cprb_msgx(bool userspace, struct ap_message *ap /* Import CPRB data from the ioctl input parameter */ if (z_copy_from_user(userspace, msg->userdata, - (char __force __user *)xcrb->req, xcrb->req_len)) { + (char __force __user *)xcrb->req, xcrb->req_len)) return -EFAULT; - } + /* pad tail with 0 up to req_len */ + if (xcrb->req_len < req_len) + memset(msg->userdata + xcrb->req_len, 0, + req_len - xcrb->req_len); + + pld = msg->userdata + sizeof(struct ep11_cprb); + pld_len = msg->cprbx.payload_len; + if (pld_len != xcrb->req_len - sizeof(struct ep11_cprb)) + return -EINVAL; + /* + * At this point pld_len is always >= MIN_EP11_PAYLOAD_SIZE + * and the smallest supported asn1 payload is: + * payload tag (1 octet) + * payload length (1-5 octets) + * function tag (1 octet) + * function length (1-5 octets) + * function value (1-4 octets) + */ - if ((msg->pld_lenfmt & 0x80) == 0x80) { /*ext.len.fmt 2 or 3*/ - switch (msg->pld_lenfmt & 0x03) { - case 1: - lfmt = 2; - break; - case 2: - lfmt = 3; - break; - default: - return -EINVAL; - } - } else { - lfmt = 1; /* length format #1 */ - } - payload_hdr = (struct pld_hdr *)((&msg->pld_lenfmt) + lfmt); - *fcode = payload_hdr->func_val & 0xFFFF; + /* payload tag */ + if (pld[offs++] != 0x30) + return -EINVAL; + /* payload length field */ + i = asn1_length_decode(pld + offs, pld_len - offs, &u); + if (i < 0) + return -EINVAL; + offs += i; + if (offs >= pld_len || u > pld_len - offs) + return -EINVAL; + /* function tag */ + if (pld[offs++] != 0x04) + return -EINVAL; + /* function length */ + if (offs >= pld_len) + return -EINVAL; + i = asn1_length_decode(pld + offs, pld_len - offs, &u); + if (i < 0) + return -EINVAL; + offs += i; + if (offs >= pld_len || u > pld_len - offs) + return -EINVAL; + /* function value */ + i = asn1_int_decode(pld + offs, u, &u); + if (i < 0) + return -EINVAL; + offs += i; + *fcode = 0xFFFF & u; /* enable special processing based on the cprbs flags special bit */ if (msg->cprbx.flags & 0x20) @@ -1160,6 +1235,28 @@ int prep_ep11_ap_msg(bool userspace, struct ep11_urb *xcrb, } /* + * Simple asn1 int writer/encoder helper function + * Returns number of bytes processed or < 0 on failure + * Only accepts int length values of 1, 2 or 4. + */ +static inline int asn1_int_encode(u8 *buf, size_t intlen, u32 u) +{ + switch (intlen) { + case 1: + *buf = (u8)u; + return 1; + case 2: + put_unaligned_be16((u16)u, buf); + return 2; + case 4: + put_unaligned_be32((u32)u, buf); + return 4; + default: + return -EINVAL; + } +} + +/* * The request distributor calls this function if it picked the CEX4P * device to handle a send_ep11_cprb request. * @zq: pointer to zcrypt_queue structure that identifies the @@ -1171,51 +1268,94 @@ static long zcrypt_msgtype6_send_ep11_cprb(bool userspace, struct zcrypt_queue * struct ap_message *ap_msg) { int rc; - unsigned int lfmt; struct ap_response_type *resp_type = &ap_msg->response; struct { struct type6_hdr hdr; struct ep11_cprb cprbx; - unsigned char pld_tag; /* fixed value 0x30 */ - unsigned char pld_lenfmt; /* payload length format */ } __packed * msg = ap_msg->msg; - struct pld_hdr { - unsigned char func_tag; /* fixed value 0x4 */ - unsigned char func_len; /* fixed value 0x4 */ - unsigned int func_val; /* function ID */ - unsigned char dom_tag; /* fixed value 0x4 */ - unsigned char dom_len; /* fixed value 0x4 */ - unsigned int dom_val; /* domain id */ - } __packed * payload_hdr = NULL; /* * The target domain field within the cprb body/payload block will be * replaced by the usage domain for non-management commands only. * Therefore we check the first bit of the 'flags' parameter for * management command indication. - * 0 - non management command - * 1 - management command */ - if (!((msg->cprbx.flags & 0x80) == 0x80)) { - msg->cprbx.target_id = (unsigned int) - AP_QID_QUEUE(zq->queue->qid); - - if ((msg->pld_lenfmt & 0x80) == 0x80) { /*ext.len.fmt 2 or 3*/ - switch (msg->pld_lenfmt & 0x03) { - case 1: - lfmt = 2; - break; - case 2: - lfmt = 3; - break; - default: + if (!(msg->cprbx.flags & 0x80)) { + int i, offs = 0; + size_t pld_len; + u8 *pld; + u32 u; + + /* update target field in ep11_cprb */ + msg->cprbx.target_id = (u32)AP_QID_QUEUE(zq->queue->qid); + + /* ptr and length to payload */ + pld = ap_msg->msg + + sizeof(struct type6_hdr) + sizeof(struct ep11_cprb); + pld_len = msg->cprbx.payload_len; + if (pld_len < MIN_EP11_PAYLOAD_SIZE) + return -EINVAL; + + /* + * Parse the asn1 payload, at least we have + * pld tag (1 octet) + * payload length (1-5 octets) + * function tag (1 octet) + * function length (1-5 octets) + * function value (1-4 octets) + * ----- optional fields ----- + * domain tag (1 octet) + * domain length (1-5 octets) + * domain value (1-4 octets) + * ... maybe much more data ... + */ + + /* payload tag */ + if (pld[offs++] != 0x30) + return -EINVAL; + /* payload length field */ + i = asn1_length_decode(pld + offs, pld_len - offs, &u); + if (i < 0) + return -EINVAL; + offs += i; + if (offs >= pld_len || u > pld_len - offs) + return -EINVAL; + /* function tag */ + if (pld[offs++] != 0x04) + return -EINVAL; + /* function length */ + if (offs >= pld_len) + return -EINVAL; + i = asn1_length_decode(pld + offs, pld_len - offs, &u); + if (i < 0) + return -EINVAL; + offs += i; + if (u > pld_len - offs) + return -EINVAL; + /* skip over the function value */ + offs += u; + /* is there some payload left which could hold a domain value ? */ + if (offs < pld_len && pld_len - offs >= 3) { + /* domain tag */ + if (pld[offs++] != 0x04) return -EINVAL; - } - } else { - lfmt = 1; /* length format #1 */ + /* domain length */ + i = asn1_length_decode(pld + offs, pld_len - offs, &u); + if (i < 0) + return -EINVAL; + offs += i; + if (offs >= pld_len || u > pld_len - offs) + return -EINVAL; + /* + * pld[offs] is now at the start of the domain value + * with the value sprawled in u octets. + */ + i = asn1_int_encode(pld + offs, u, + AP_QID_QUEUE(zq->queue->qid)); + if (i < 0) + return -EINVAL; + offs += i; } - payload_hdr = (struct pld_hdr *)((&msg->pld_lenfmt) + lfmt); - payload_hdr->dom_val = AP_QID_QUEUE(zq->queue->qid); } /*