diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index c7fc10724948..98ac0d7552a1 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -1514,6 +1514,20 @@ cookie_preserve_enable - BOOLEAN Default: 1 +cookie_hmac_alg - STRING + Select the hmac algorithm used when generating the cookie value sent by + a listening sctp socket to a connecting client in the INIT-ACK chunk. + Valid values are: + * md5 + * sha1 + * none + Ability to assign md5 or sha1 as the selected alg is predicated on the + configuarion of those algorithms at build time (CONFIG_CRYPTO_MD5 and + CONFIG_CRYPTO_SHA1). + + Default: Dependent on configuration. MD5 if available, else SHA1 if + available, else none. + rcvbuf_policy - INTEGER Determines if the receive buffer is attributed to the socket or to association. SCTP supports the capability to create multiple diff --git a/include/net/netns/sctp.h b/include/net/netns/sctp.h index 5e5eb1f9f14b..3573a81815ad 100644 --- a/include/net/netns/sctp.h +++ b/include/net/netns/sctp.h @@ -62,6 +62,9 @@ struct netns_sctp { /* Whether Cookie Preservative is enabled(1) or not(0) */ int cookie_preserve_enable; + /* The namespace default hmac alg */ + char *sctp_hmac_alg; + /* Valid.Cookie.Life - 60 seconds */ unsigned int valid_cookie_life; diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h index d053d2e99876..c29707d654c0 100644 --- a/include/net/sctp/constants.h +++ b/include/net/sctp/constants.h @@ -312,14 +312,6 @@ enum { SCTP_MAX_GABS = 16 }; * functions simpler to write. */ -#if defined (CONFIG_SCTP_HMAC_MD5) -#define SCTP_COOKIE_HMAC_ALG "hmac(md5)" -#elif defined (CONFIG_SCTP_HMAC_SHA1) -#define SCTP_COOKIE_HMAC_ALG "hmac(sha1)" -#else -#define SCTP_COOKIE_HMAC_ALG NULL -#endif - /* These return values describe the success or failure of a number of * routines which form the lower interface to SCTP_outqueue. */ diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index 64158aa1bb5f..2b2f61dd4036 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -177,6 +177,7 @@ struct sctp_sock { /* Access to HMAC transform. */ struct crypto_hash *hmac; + char *sctp_hmac_alg; /* What is our base endpointer? */ struct sctp_endpoint *ep; diff --git a/net/sctp/Kconfig b/net/sctp/Kconfig index 126b014eb79b..a9edd2e205f4 100644 --- a/net/sctp/Kconfig +++ b/net/sctp/Kconfig @@ -9,7 +9,6 @@ menuconfig IP_SCTP select CRYPTO select CRYPTO_HMAC select CRYPTO_SHA1 - select CRYPTO_MD5 if SCTP_HMAC_MD5 select LIBCRC32C ---help--- Stream Control Transmission Protocol @@ -68,33 +67,21 @@ config SCTP_DBG_OBJCNT If unsure, say N -choice - prompt "SCTP: Cookie HMAC Algorithm" - default SCTP_HMAC_MD5 +config SCTP_COOKIE_HMAC_MD5 + bool "Enable optional MD5 hmac cookie generation" help - HMAC algorithm to be used during association initialization. It - is strongly recommended to use HMAC-SHA1 or HMAC-MD5. See - configuration for Cryptographic API and enable those algorithms - to make usable by SCTP. + Enable optional MD5 hmac based SCTP cookie generation + default y + select CRYPTO_HMAC if SCTP_COOKIE_HMAC_MD5 + select CRYPTO_MD5 if SCTP_COOKIE_HMAC_MD5 -config SCTP_HMAC_NONE - bool "None" - help - Choosing this disables the use of an HMAC during association - establishment. It is advised to use either HMAC-MD5 or HMAC-SHA1. - -config SCTP_HMAC_SHA1 - bool "HMAC-SHA1" - help - Enable the use of HMAC-SHA1 during association establishment. It - is advised to use either HMAC-MD5 or HMAC-SHA1. - -config SCTP_HMAC_MD5 - bool "HMAC-MD5" +config SCTP_COOKIE_HMAC_SHA1 + bool "Enable optional SHA1 hmac cookie generation" help - Enable the use of HMAC-MD5 during association establishment. It is - advised to use either HMAC-MD5 or HMAC-SHA1. + Enable optional SHA1 hmac based SCTP cookie generation + default y + select CRYPTO_HMAC if SCTP_COOKIE_HMAC_SHA1 + select CRYPTO_SHA1 if SCTP_COOKIE_HMAC_SHA1 -endchoice endif # IP_SCTP diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 2d518425d598..456bc3dbdd51 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -1190,6 +1190,15 @@ static int sctp_net_init(struct net *net) /* Whether Cookie Preservative is enabled(1) or not(0) */ net->sctp.cookie_preserve_enable = 1; + /* Default sctp sockets to use md5 as their hmac alg */ +#if defined (CONFIG_CRYPTO_MD5) + net->sctp.sctp_hmac_alg = "md5"; +#elif defined (CONFIG_CRYPTO_SHA1) + net->sctp.sctp_hmac_alg = "sha1"; +#else + net->sctp.sctp_hmac_alg = NULL; +#endif + /* Max.Burst - 4 */ net->sctp.max_burst = SCTP_DEFAULT_MAX_BURST; diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 59d16ea927f0..fa81bdee00a5 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -110,7 +110,6 @@ static int sctp_do_bind(struct sock *, union sctp_addr *, int); static int sctp_autobind(struct sock *sk); static void sctp_sock_migrate(struct sock *, struct sock *, struct sctp_association *, sctp_socket_type_t); -static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG; extern struct kmem_cache *sctp_bucket_cachep; extern long sysctl_sctp_mem[3]; @@ -3890,6 +3889,8 @@ SCTP_STATIC int sctp_init_sock(struct sock *sk) sp->default_rcv_context = 0; sp->max_burst = net->sctp.max_burst; + sp->sctp_hmac_alg = net->sctp.sctp_hmac_alg; + /* Initialize default setup parameters. These parameters * can be modified with the SCTP_INITMSG socket option or * overridden by the SCTP_INIT CMSG. @@ -5981,13 +5982,15 @@ SCTP_STATIC int sctp_listen_start(struct sock *sk, int backlog) struct sctp_sock *sp = sctp_sk(sk); struct sctp_endpoint *ep = sp->ep; struct crypto_hash *tfm = NULL; + char alg[32]; /* Allocate HMAC for generating cookie. */ - if (!sctp_sk(sk)->hmac && sctp_hmac_alg) { - tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC); + if (!sp->hmac && sp->sctp_hmac_alg) { + sprintf(alg, "hmac(%s)", sp->sctp_hmac_alg); + tfm = crypto_alloc_hash(alg, 0, CRYPTO_ALG_ASYNC); if (IS_ERR(tfm)) { net_info_ratelimited("failed to load transform for %s: %ld\n", - sctp_hmac_alg, PTR_ERR(tfm)); + sp->sctp_hmac_alg, PTR_ERR(tfm)); return -ENOSYS; } sctp_sk(sk)->hmac = tfm; diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c index 70e3ba5cb50b..043889ac86c0 100644 --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -62,6 +62,11 @@ extern long sysctl_sctp_mem[3]; extern int sysctl_sctp_rmem[3]; extern int sysctl_sctp_wmem[3]; +static int proc_sctp_do_hmac_alg(ctl_table *ctl, + int write, + void __user *buffer, size_t *lenp, + + loff_t *ppos); static ctl_table sctp_table[] = { { .procname = "sctp_mem", @@ -146,6 +151,12 @@ static ctl_table sctp_net_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, + { + .procname = "cookie_hmac_alg", + .maxlen = 8, + .mode = 0644, + .proc_handler = proc_sctp_do_hmac_alg, + }, { .procname = "valid_cookie_life", .data = &init_net.sctp.valid_cookie_life, @@ -289,6 +300,54 @@ static ctl_table sctp_net_table[] = { { /* sentinel */ } }; +static int proc_sctp_do_hmac_alg(ctl_table *ctl, + int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + struct net *net = current->nsproxy->net_ns; + char tmp[8]; + ctl_table tbl; + int ret; + int changed = 0; + char *none = "none"; + + memset(&tbl, 0, sizeof(struct ctl_table)); + + if (write) { + tbl.data = tmp; + tbl.maxlen = 8; + } else { + tbl.data = net->sctp.sctp_hmac_alg ? : none; + tbl.maxlen = strlen(tbl.data); + } + ret = proc_dostring(&tbl, write, buffer, lenp, ppos); + + if (write) { +#ifdef CONFIG_CRYPTO_MD5 + if (!strncmp(tmp, "md5", 3)) { + net->sctp.sctp_hmac_alg = "md5"; + changed = 1; + } +#endif +#ifdef CONFIG_CRYPTO_SHA1 + if (!strncmp(tmp, "sha1", 4)) { + net->sctp.sctp_hmac_alg = "sha1"; + changed = 1; + } +#endif + if (!strncmp(tmp, "none", 4)) { + net->sctp.sctp_hmac_alg = NULL; + changed = 1; + } + + if (!changed) + ret = -EINVAL; + } + + return ret; +} + int sctp_sysctl_net_register(struct net *net) { struct ctl_table *table;