From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- lib/oid_registry.c | 175 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 175 insertions(+) create mode 100644 lib/oid_registry.c (limited to 'lib/oid_registry.c') diff --git a/lib/oid_registry.c b/lib/oid_registry.c new file mode 100644 index 000000000..9b757a117 --- /dev/null +++ b/lib/oid_registry.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* ASN.1 Object identifier (OID) registry + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include +#include +#include +#include +#include +#include +#include +#include "oid_registry_data.c" + +MODULE_DESCRIPTION("OID Registry"); +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_LICENSE("GPL"); + +/** + * look_up_OID - Find an OID registration for the specified data + * @data: Binary representation of the OID + * @datasize: Size of the binary representation + */ +enum OID look_up_OID(const void *data, size_t datasize) +{ + const unsigned char *octets = data; + enum OID oid; + unsigned char xhash; + unsigned i, j, k, hash; + size_t len; + + /* Hash the OID data */ + hash = datasize - 1; + + for (i = 0; i < datasize; i++) + hash += octets[i] * 33; + hash = (hash >> 24) ^ (hash >> 16) ^ (hash >> 8) ^ hash; + hash &= 0xff; + + /* Binary search the OID registry. OIDs are stored in ascending order + * of hash value then ascending order of size and then in ascending + * order of reverse value. + */ + i = 0; + k = OID__NR; + while (i < k) { + j = (i + k) / 2; + + xhash = oid_search_table[j].hash; + if (xhash > hash) { + k = j; + continue; + } + if (xhash < hash) { + i = j + 1; + continue; + } + + oid = oid_search_table[j].oid; + len = oid_index[oid + 1] - oid_index[oid]; + if (len > datasize) { + k = j; + continue; + } + if (len < datasize) { + i = j + 1; + continue; + } + + /* Variation is most likely to be at the tail end of the + * OID, so do the comparison in reverse. + */ + while (len > 0) { + unsigned char a = oid_data[oid_index[oid] + --len]; + unsigned char b = octets[len]; + if (a > b) { + k = j; + goto next; + } + if (a < b) { + i = j + 1; + goto next; + } + } + return oid; + next: + ; + } + + return OID__NR; +} +EXPORT_SYMBOL_GPL(look_up_OID); + +/** + * parse_OID - Parse an OID from a bytestream + * @data: Binary representation of the header + OID + * @datasize: Size of the binary representation + * @oid: Pointer to oid to return result + * + * Parse an OID from a bytestream that holds the OID in the format + * ASN1_OID | length | oid. The length indicator must equal to datasize - 2. + * -EBADMSG is returned if the bytestream is too short. + */ +int parse_OID(const void *data, size_t datasize, enum OID *oid) +{ + const unsigned char *v = data; + + /* we need 2 bytes of header and at least 1 byte for oid */ + if (datasize < 3 || v[0] != ASN1_OID || v[1] != datasize - 2) + return -EBADMSG; + + *oid = look_up_OID(data + 2, datasize - 2); + return 0; +} +EXPORT_SYMBOL_GPL(parse_OID); + +/* + * sprint_oid - Print an Object Identifier into a buffer + * @data: The encoded OID to print + * @datasize: The size of the encoded OID + * @buffer: The buffer to render into + * @bufsize: The size of the buffer + * + * The OID is rendered into the buffer in "a.b.c.d" format and the number of + * bytes is returned. -EBADMSG is returned if the data could not be interpreted + * and -ENOBUFS if the buffer was too small. + */ +int sprint_oid(const void *data, size_t datasize, char *buffer, size_t bufsize) +{ + const unsigned char *v = data, *end = v + datasize; + unsigned long num; + unsigned char n; + size_t ret; + int count; + + if (v >= end) + goto bad; + + n = *v++; + ret = count = snprintf(buffer, bufsize, "%u.%u", n / 40, n % 40); + if (count >= bufsize) + return -ENOBUFS; + buffer += count; + bufsize -= count; + + while (v < end) { + n = *v++; + if (!(n & 0x80)) { + num = n; + } else { + num = n & 0x7f; + do { + if (v >= end) + goto bad; + n = *v++; + num <<= 7; + num |= n & 0x7f; + } while (n & 0x80); + } + ret += count = snprintf(buffer, bufsize, ".%lu", num); + if (count >= bufsize) + return -ENOBUFS; + buffer += count; + bufsize -= count; + } + + return ret; + +bad: + snprintf(buffer, bufsize, "(bad)"); + return -EBADMSG; +} +EXPORT_SYMBOL_GPL(sprint_oid); -- cgit v1.3.1