kernel/linux.git/net/sctp/Kconfig, branch linux-7.1.y

ipv6: convert CONFIG_IPV6 to built-in only and clean up Kconfigs

2026-03-29T18:21:22+00:00

Maintaining a modular IPv6 stack offers image size savings for specific setups, this benefit is outweighed by the architectural burden it imposes on the subsystems on implementation and maintenance. Therefore, drop it. Change CONFIG_IPV6 from tristate to bool. Remove all Kconfig dependencies across the tree that explicitly checked for IPV6=m. In addition, remove MODULE_DESCRIPTION(), MODULE_ALIAS(), MODULE_AUTHOR() and MODULE_LICENSE(). This is also replacing module_init() by device_initcall(). It is not possible to use fs_initcall() as IPv4 does because that creates a race condition on IPv6 addrconf. Finally, modify the default configs from CONFIG_IPV6=m to CONFIG_IPV6=y except for m68k as according to the bloat-o-meter the image is increasing by 330KB~ and that isn't acceptable. Instead, disable IPv6 on this architecture by default. This is aligned with m68k RAM requirements and recommendations [1]. [1] http://www.linux-m68k.org/faq/ram.html Signed-off-by: Fernando Fernandez Mancera Tested-by: Ricardo B. Marlière Acked-by: Krzysztof Kozlowski # arm64 Link: https://patch.msgid.link/20260325120928.15848-2-fmancera@suse.de Signed-off-by: Jakub Kicinski

sctp: Convert cookie authentication to use HMAC-SHA256

2025-08-20T02:36:26+00:00

Convert SCTP cookies to use HMAC-SHA256, instead of the previous choice of the legacy algorithms HMAC-MD5 and HMAC-SHA1. Simplify and optimize the code by using the HMAC-SHA256 library instead of crypto_shash, and by preparing the HMAC key when it is generated instead of per-operation. This doesn't break compatibility, since the cookie format is an implementation detail, not part of the SCTP protocol itself. Note that the cookie size doesn't change either. The HMAC field was already 32 bytes, even though previously at most 20 bytes were actually compared. 32 bytes exactly fits an untruncated HMAC-SHA256 value. So, although we could safely truncate the MAC to something slightly shorter, for now just keep the cookie size the same. I also considered SipHash, but that would generate only 8-byte MACs. An 8-byte MAC *might* suffice here. However, there's quite a lot of information in the SCTP cookies: more than in TCP SYN cookies. So absent an analysis that occasional forgeries of all that information is okay in SCTP, I errored on the side of caution. Remove HMAC-MD5 and HMAC-SHA1 as options, since the new HMAC-SHA256 option is just better. It's faster as well as more secure. For example, benchmarking on x86_64, cookie authentication is now nearly 3x as fast as the previous default choice and implementation of HMAC-MD5. Also just make the kernel always support cookie authentication if SCTP is supported at all, rather than making it optional in the build. (It was sort of optional before, but it didn't really work properly. E.g., a kernel with CONFIG_SCTP_COOKIE_HMAC_MD5=n still supported HMAC-MD5 cookie authentication if CONFIG_CRYPTO_HMAC and CONFIG_CRYPTO_MD5 happened to be enabled in the kconfig for other reasons.) Acked-by: Xin Long Signed-off-by: Eric Biggers Link: https://patch.msgid.link/20250818205426.30222-5-ebiggers@kernel.org Signed-off-by: Jakub Kicinski

sctp: Use HMAC-SHA1 and HMAC-SHA256 library for chunk authentication

2025-08-20T02:36:25+00:00

For SCTP chunk authentication, use the HMAC-SHA1 and HMAC-SHA256 library functions instead of crypto_shash. This is simpler and faster. There's no longer any need to pre-allocate 'crypto_shash' objects; the SCTP code now simply calls into the HMAC code directly. As part of this, make SCTP always support both HMAC-SHA1 and HMAC-SHA256. Previously, it only guaranteed support for HMAC-SHA1. However, HMAC-SHA256 tended to be supported too anyway, as it was supported if CONFIG_CRYPTO_SHA256 was enabled elsewhere in the kconfig. Acked-by: Xin Long Signed-off-by: Eric Biggers Link: https://patch.msgid.link/20250818205426.30222-4-ebiggers@kernel.org Signed-off-by: Jakub Kicinski

sctp: use skb_crc32c() instead of __skb_checksum()

2025-05-21T22:40:16+00:00

Make sctp_compute_cksum() just use the new function skb_crc32c(), instead of calling __skb_checksum() with a skb_checksum_ops struct that does CRC32C. This is faster and simpler. Signed-off-by: Eric Biggers Reviewed-by: Hannes Reinecke Link: https://patch.msgid.link/20250519175012.36581-6-ebiggers@kernel.org Signed-off-by: Jakub Kicinski

net: introduce CONFIG_NET_CRC32C

2025-05-21T22:39:58+00:00

Add a hidden kconfig symbol NET_CRC32C that will group together the functions that calculate CRC32C checksums of packets, so that these don't have to be built into NET-enabled kernels that don't need them. Make skb_crc32c_csum_help() (which is called only when IP_SCTP is enabled) conditional on this symbol, and make IP_SCTP select it. Signed-off-by: Eric Biggers Reviewed-by: Hannes Reinecke Link: https://patch.msgid.link/20250519175012.36581-2-ebiggers@kernel.org Signed-off-by: Jakub Kicinski

lib/crc: remove CONFIG_LIBCRC32C

2025-04-04T18:31:42+00:00

Now that LIBCRC32C does nothing besides select CRC32, make every option that selects LIBCRC32C instead select CRC32 directly. Then remove LIBCRC32C. Reviewed-by: Christoph Hellwig Reviewed-by: "Martin K. Petersen" Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250401221600.24878-8-ebiggers@kernel.org Signed-off-by: Eric Biggers

sctp: create udp4 sock and add its encap_rcv

2020-10-30T22:23:52+00:00

This patch is to add the functions to create/release udp4 sock, and set the sock's encap_rcv to process the incoming udp encap sctp packets. In sctp_udp_rcv(), as we can see, all we need to do is fix the transport header for sctp_rcv(), then it would implement the part of rfc6951#section-5.4: "When an encapsulated packet is received, the UDP header is removed. Then, the generic lookup is performed, as done by an SCTP stack whenever a packet is received, to find the association for the received SCTP packet" Note that these functions will be called in the last patch of this patchset when enabling this feature. v1->v2: - Add pr_err() when fails to create udp v4 sock. v2->v3: - Add 'select NET_UDP_TUNNEL' in sctp Kconfig. v3->v4: - No change. v4->v5: - Change to set udp_port to 0 by default. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: Jakub Kicinski

treewide: replace '---help---' in Kconfig files with 'help'

2020-06-13T16:57:21+00:00

Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada

net: sctp: Fix spelling in Kconfig help

2020-05-27T03:32:06+00:00

Change 'handeled' to 'handled' in the Kconfig help for SCTP. Signed-off-by: Chris Packham Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

treewide: Add SPDX license identifier - Makefile/Kconfig

2019-05-21T08:50:46+00:00

Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman