Gitweb:     
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=1f485649f52929d9937b346a920a522a7363e202
Commit:     1f485649f52929d9937b346a920a522a7363e202
Parent:     f7b0e93ba1a484700bd1b0e36bdaddaf4eb51b0b
Author:     Vlad Yasevich <[EMAIL PROTECTED]>
AuthorDate: Tue Oct 9 01:15:59 2007 -0700
Committer:  David S. Miller <[EMAIL PROTECTED]>
CommitDate: Wed Oct 10 16:51:29 2007 -0700

    [SCTP]: Implement SCTP-AUTH internals
    
    This patch implements the internals operations of the AUTH, such as
    key computation and storage.  It also adds necessary variables to
    the SCTP data structures.
    
    Signed-off-by: Vlad Yasevich <[EMAIL PROTECTED]>
    Signed-off-by: David S. Miller <[EMAIL PROTECTED]>
---
 include/net/sctp/auth.h      |  112 +++++++
 include/net/sctp/constants.h |   49 +++-
 include/net/sctp/sctp.h      |    1 +
 include/net/sctp/structs.h   |   71 ++++-
 net/sctp/Makefile            |    3 +-
 net/sctp/auth.c              |  745 ++++++++++++++++++++++++++++++++++++++++++
 net/sctp/objcnt.c            |    2 +
 7 files changed, 976 insertions(+), 7 deletions(-)

diff --git a/include/net/sctp/auth.h b/include/net/sctp/auth.h
new file mode 100644
index 0000000..10c8010
--- /dev/null
+++ b/include/net/sctp/auth.h
@@ -0,0 +1,112 @@
+/* SCTP kernel reference Implementation
+ * (C) Copyright 2007 Hewlett-Packard Development Company, L.P.
+ *
+ * This file is part of the SCTP kernel reference Implementation
+ *
+ * The SCTP reference implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * The SCTP reference implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <[EMAIL PROTECTED]>
+ *
+ * Or submit a bug report through the following website:
+ *    http://www.sf.net/projects/lksctp
+ *
+ * Written or modified by:
+ *   Vlad Yasevich     <[EMAIL PROTECTED]>
+ *
+ * Any bugs reported given to us we will try to fix... any fixes shared will
+ * be incorporated into the next SCTP release.
+ */
+
+#ifndef __sctp_auth_h__
+#define __sctp_auth_h__
+
+#include <linux/list.h>
+#include <linux/crypto.h>
+
+struct sctp_endpoint;
+struct sctp_association;
+struct sctp_authkey;
+
+/*
+ * Define a generic struct that will hold all the info
+ * necessary for an HMAC transform
+ */
+struct sctp_hmac {
+       __u16 hmac_id;          /* one of the above ids */
+       char *hmac_name;        /* name for loading */
+       __u16 hmac_len;         /* length of the signature */
+};
+
+/* This is generic structure that containst authentication bytes used
+ * as keying material.  It's a what is referred to as byte-vector all
+ * over SCTP-AUTH
+ */
+struct sctp_auth_bytes {
+       atomic_t refcnt;
+       __u32 len;
+       __u8  data[];
+};
+
+/* Definition for a shared key, weather endpoint or association */
+struct sctp_shared_key {
+       struct list_head key_list;
+       __u16 key_id;
+       struct sctp_auth_bytes *key;
+};
+
+#define key_for_each(__key, __list_head) \
+       list_for_each_entry(__key, __list_head, key_list)
+
+#define key_for_each_safe(__key, __tmp, __list_head) \
+       list_for_each_entry_safe(__key, __tmp, __list_head, key_list)
+
+static inline void sctp_auth_key_hold(struct sctp_auth_bytes *key)
+{
+       if (!key)
+               return;
+
+       atomic_inc(&key->refcnt);
+}
+
+void sctp_auth_key_put(struct sctp_auth_bytes *key);
+struct sctp_shared_key *sctp_auth_shkey_create(__u16 key_id, gfp_t gfp);
+void sctp_auth_shkey_free(struct sctp_shared_key *sh_key);
+void sctp_auth_destroy_keys(struct list_head *keys);
+int sctp_auth_asoc_init_active_key(struct sctp_association *asoc, gfp_t gfp);
+struct sctp_shared_key *sctp_auth_get_shkey(
+                               const struct sctp_association *asoc,
+                               __u16 key_id);
+int sctp_auth_asoc_copy_shkeys(const struct sctp_endpoint *ep,
+                               struct sctp_association *asoc,
+                               gfp_t gfp);
+int sctp_auth_init_hmacs(struct sctp_endpoint *ep, gfp_t gfp);
+void sctp_auth_destroy_hmacs(struct crypto_hash *auth_hmacs[]);
+struct sctp_hmac *sctp_auth_get_hmac(__u16 hmac_id);
+struct sctp_hmac *sctp_auth_asoc_get_hmac(const struct sctp_association *asoc);
+void sctp_auth_asoc_set_default_hmac(struct sctp_association *asoc,
+                                    struct sctp_hmac_algo_param *hmacs);
+int sctp_auth_asoc_verify_hmac_id(const struct sctp_association *asoc,
+                                   __u16 hmac_id);
+int sctp_auth_send_cid(sctp_cid_t chunk, const struct sctp_association *asoc);
+int sctp_auth_recv_cid(sctp_cid_t chunk, const struct sctp_association *asoc);
+void sctp_auth_calculate_hmac(const struct sctp_association *asoc,
+                           struct sk_buff *skb,
+                           struct sctp_auth_chunk *auth, gfp_t gfp);
+#endif
diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h
index bb37724..777118f 100644
--- a/include/net/sctp/constants.h
+++ b/include/net/sctp/constants.h
@@ -64,12 +64,18 @@ enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM };
 #define SCTP_CID_MAX                   SCTP_CID_ASCONF_ACK
 
 #define SCTP_NUM_BASE_CHUNK_TYPES      (SCTP_CID_BASE_MAX + 1)
-#define SCTP_NUM_CHUNK_TYPES           (SCTP_NUM_BASE_CHUNKTYPES + 2)
 
 #define SCTP_NUM_ADDIP_CHUNK_TYPES     2
 
 #define SCTP_NUM_PRSCTP_CHUNK_TYPES    1
 
+#define SCTP_NUM_AUTH_CHUNK_TYPES      1
+
+#define SCTP_NUM_CHUNK_TYPES           (SCTP_NUM_BASE_CHUNK_TYPES + \
+                                        SCTP_NUM_ADDIP_CHUNK_TYPES +\
+                                        SCTP_NUM_PRSCTP_CHUNK_TYPES +\
+                                        SCTP_NUM_AUTH_CHUNK_TYPES)
+
 /* These are the different flavours of event.  */
 typedef enum {
 
@@ -409,4 +415,45 @@ typedef enum {
        SCTP_LOWER_CWND_INACTIVE,
 } sctp_lower_cwnd_t;
 
+
+/* SCTP-AUTH Necessary constants */
+
+/* SCTP-AUTH, Section 3.3
+ *
+ *  The following Table 2 shows the currently defined values for HMAC
+ *  identifiers.
+ *
+ *  +-----------------+--------------------------+
+ *  | HMAC Identifier | Message Digest Algorithm |
+ *  +-----------------+--------------------------+
+ *  | 0               | Reserved                 |
+ *  | 1               | SHA-1 defined in [8]     |
+ *  | 2               | Reserved                 |
+ *  | 3               | SHA-256 defined in [8]   |
+ *  +-----------------+--------------------------+
+ */
+enum {
+       SCTP_AUTH_HMAC_ID_RESERVED_0,
+       SCTP_AUTH_HMAC_ID_SHA1,
+       SCTP_AUTH_HMAC_ID_RESERVED_2,
+       SCTP_AUTH_HMAC_ID_SHA256
+};
+
+#define SCTP_AUTH_HMAC_ID_MAX  SCTP_AUTH_HMAC_ID_SHA256
+#define SCTP_AUTH_NUM_HMACS (SCTP_AUTH_HMAC_ID_SHA256 + 1)
+#define SCTP_SHA1_SIG_SIZE 20
+#define SCTP_SHA256_SIG_SIZE 32
+
+/*  SCTP-AUTH, Section 3.2
+ *     The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks
+ *     MUST NOT be listed in the CHUNKS parameter
+ */
+#define SCTP_NUM_NOAUTH_CHUNKS 4
+#define SCTP_AUTH_MAX_CHUNKS   (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS)
+
+/* SCTP-AUTH Section 6.1
+ * The RANDOM parameter MUST contain a 32 byte random number.
+ */
+#define SCTP_AUTH_RANDOM_LENGTH 32
+
 #endif /* __sctp_constants_h__ */
diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index d5a1ddc..119f5a1 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -341,6 +341,7 @@ extern atomic_t sctp_dbg_objcnt_bind_bucket;
 extern atomic_t sctp_dbg_objcnt_addr;
 extern atomic_t sctp_dbg_objcnt_ssnmap;
 extern atomic_t sctp_dbg_objcnt_datamsg;
+extern atomic_t sctp_dbg_objcnt_keys;
 
 /* Macros to atomically increment/decrement objcnt counters.  */
 #define SCTP_DBG_OBJCNT_INC(name) \
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index b4812a2..18b06af 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -64,6 +64,7 @@
 #include <linux/skbuff.h>      /* We need sk_buff_head. */
 #include <linux/workqueue.h>   /* We need tq_struct.    */
 #include <linux/sctp.h>                /* We need sctp* header structs.  */
+#include <net/sctp/auth.h>     /* We need auth specific structs */
 
 /* A convenience structure for handling sockaddr structures.
  * We should wean ourselves off this.
@@ -216,6 +217,9 @@ extern struct sctp_globals {
 
        /* Flag to indicate if PR-SCTP is enabled. */
        int prsctp_enable;
+
+       /* Flag to idicate if SCTP-AUTH is enabled */
+       int auth_enable;
 } sctp_globals;
 
 #define sctp_rto_initial               (sctp_globals.rto_initial)
@@ -248,6 +252,7 @@ extern struct sctp_globals {
 #define sctp_local_addr_lock           (sctp_globals.addr_list_lock)
 #define sctp_addip_enable              (sctp_globals.addip_enable)
 #define sctp_prsctp_enable             (sctp_globals.prsctp_enable)
+#define sctp_auth_enable               (sctp_globals.auth_enable)
 
 /* SCTP Socket type: UDP or TCP style. */
 typedef enum {
@@ -397,6 +402,9 @@ struct sctp_cookie {
 
        __u32 adaptation_ind;
 
+       __u8 auth_random[sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH];
+       __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS + 2];
+       __u8 auth_chunks[sizeof(sctp_paramhdr_t) + SCTP_AUTH_MAX_CHUNKS];
 
        /* This is a shim for my peer's INIT packet, followed by
         * a copy of the raw address list of the association.
@@ -441,6 +449,9 @@ union sctp_params {
        union sctp_addr_param *addr;
        struct sctp_adaptation_ind_param *aind;
        struct sctp_supported_ext_param *ext;
+       struct sctp_random_param *random;
+       struct sctp_chunks_param *chunks;
+       struct sctp_hmac_algo_param *hmac_algo;
 };
 
 /* RFC 2960.  Section 3.3.5 Heartbeat.
@@ -679,6 +690,7 @@ struct sctp_chunk {
                struct sctp_errhdr *err_hdr;
                struct sctp_addiphdr *addip_hdr;
                struct sctp_fwdtsn_hdr *fwdtsn_hdr;
+               struct sctp_authhdr *auth_hdr;
        } subh;
 
        __u8 *chunk_end;
@@ -724,6 +736,7 @@ struct sctp_chunk {
        __s8 fast_retransmit;    /* Is this chunk fast retransmitted? */
        __u8 tsn_missing_report; /* Data chunk missing counter. */
        __u8 data_accepted;     /* At least 1 chunk in this packet accepted */
+       __u8 auth;              /* IN: was auth'ed | OUT: needs auth */
 };
 
 void sctp_chunk_hold(struct sctp_chunk *);
@@ -773,16 +786,22 @@ struct sctp_packet {
         */
        struct sctp_transport *transport;
 
+       /* pointer to the auth chunk for this packet */
+       struct sctp_chunk *auth;
+
        /* This packet contains a COOKIE-ECHO chunk. */
-       char has_cookie_echo;
+       __u8 has_cookie_echo;
+
+       /* This packet contains a SACK chunk. */
+       __u8 has_sack;
 
-       /* This packet containsa SACK chunk. */
-       char has_sack;
+       /* This packet contains an AUTH chunk */
+       __u8 has_auth;
 
        /* SCTP cannot fragment this packet. So let ip fragment it. */
-       char ipfragok;
+       __u8 ipfragok;
 
-       int malloced;
+       __u8 malloced;
 };
 
 struct sctp_packet *sctp_packet_init(struct sctp_packet *,
@@ -1291,6 +1310,21 @@ struct sctp_endpoint {
 
        /* rcvbuf acct. policy. */
        __u32 rcvbuf_policy;
+
+       /* SCTP AUTH: array of the HMACs that will be allocated
+        * we need this per association so that we don't serialize
+        */
+       struct crypto_hash **auth_hmacs;
+
+       /* SCTP-AUTH: hmacs for the endpoint encoded into parameter */
+        struct sctp_hmac_algo_param *auth_hmacs_list;
+
+       /* SCTP-AUTH: chunks to authenticate encoded into parameter */
+       struct sctp_chunks_param *auth_chunk_list;
+
+       /* SCTP-AUTH: endpoint shared keys */
+       struct list_head endpoint_shared_keys;
+       __u16 active_key_id;
 };
 
 /* Recover the outter endpoint structure. */
@@ -1497,6 +1531,7 @@ struct sctp_association {
                __u8    hostname_address;/* Peer understands DNS addresses? */
                __u8    asconf_capable;  /* Does peer support ADDIP? */
                __u8    prsctp_capable;  /* Can peer do PR-SCTP? */
+               __u8    auth_capable;    /* Is peer doing SCTP-AUTH? */
 
                __u32   adaptation_ind;  /* Adaptation Code point. */
 
@@ -1514,6 +1549,14 @@ struct sctp_association {
                 * Initial TSN Value minus 1
                 */
                __u32 addip_serial;
+
+               /* SCTP-AUTH: We need to know pears random number, hmac list
+                * and authenticated chunk list.  All that is part of the
+                * cookie and these are just pointers to those locations
+                */
+               sctp_random_param_t *peer_random;
+               sctp_chunks_param_t *peer_chunks;
+               sctp_hmac_algo_param_t *peer_hmacs;
        } peer;
 
        /* State       : A state variable indicating what state the
@@ -1797,6 +1840,24 @@ struct sctp_association {
         */
        __u32 addip_serial;
 
+       /* SCTP AUTH: list of the endpoint shared keys.  These
+        * keys are provided out of band by the user applicaton
+        * and can't change during the lifetime of the association
+        */
+       struct list_head endpoint_shared_keys;
+
+       /* SCTP AUTH:
+        * The current generated assocaition shared key (secret)
+        */
+       struct sctp_auth_bytes *asoc_shared_key;
+
+       /* SCTP AUTH: hmac id of the first peer requested algorithm
+        * that we support.
+        */
+       __u16 default_hmac_id;
+
+       __u16 active_key_id;
+
        /* Need to send an ECNE Chunk? */
        char need_ecne;
 
diff --git a/net/sctp/Makefile b/net/sctp/Makefile
index 70c828b..1da7204 100644
--- a/net/sctp/Makefile
+++ b/net/sctp/Makefile
@@ -9,7 +9,8 @@ sctp-y := sm_statetable.o sm_statefuns.o sm_sideeffect.o \
          transport.o chunk.o sm_make_chunk.o ulpevent.o \
          inqueue.o outqueue.o ulpqueue.o command.o \
          tsnmap.o bind_addr.o socket.o primitive.o \
-         output.o input.o debug.o ssnmap.o proc.o crc32c.o
+         output.o input.o debug.o ssnmap.o proc.o crc32c.o \
+         auth.o
 
 sctp-$(CONFIG_SCTP_DBG_OBJCNT) += objcnt.o
 sctp-$(CONFIG_SYSCTL) += sysctl.o
diff --git a/net/sctp/auth.c b/net/sctp/auth.c
new file mode 100644
index 0000000..2a29409
--- /dev/null
+++ b/net/sctp/auth.c
@@ -0,0 +1,745 @@
+/* SCTP kernel reference Implementation
+ * (C) Copyright 2007 Hewlett-Packard Development Company, L.P.
+ *
+ * This file is part of the SCTP kernel reference Implementation
+ *
+ * The SCTP reference implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * The SCTP reference implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <[EMAIL PROTECTED]>
+ *
+ * Or submit a bug report through the following website:
+ *    http://www.sf.net/projects/lksctp
+ *
+ * Written or modified by:
+ *   Vlad Yasevich     <[EMAIL PROTECTED]>
+ *
+ * Any bugs reported given to us we will try to fix... any fixes shared will
+ * be incorporated into the next SCTP release.
+ */
+
+#include <linux/types.h>
+#include <linux/crypto.h>
+#include <linux/scatterlist.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/auth.h>
+
+static struct sctp_hmac sctp_hmac_list[SCTP_AUTH_NUM_HMACS] = {
+       {
+               /* id 0 is reserved.  as all 0 */
+               .hmac_id = SCTP_AUTH_HMAC_ID_RESERVED_0,
+       },
+       {
+               .hmac_id = SCTP_AUTH_HMAC_ID_SHA1,
+               .hmac_name="hmac(sha1)",
+               .hmac_len = SCTP_SHA1_SIG_SIZE,
+       },
+       {
+               /* id 2 is reserved as well */
+               .hmac_id = SCTP_AUTH_HMAC_ID_RESERVED_2,
+       },
+       {
+               .hmac_id = SCTP_AUTH_HMAC_ID_SHA256,
+               .hmac_name="hmac(sha256)",
+               .hmac_len = SCTP_SHA256_SIG_SIZE,
+       }
+};
+
+
+void sctp_auth_key_put(struct sctp_auth_bytes *key)
+{
+       if (!key)
+               return;
+
+       if (atomic_dec_and_test(&key->refcnt)) {
+               kfree(key);
+               SCTP_DBG_OBJCNT_DEC(keys);
+       }
+}
+
+/* Create a new key structure of a given length */
+static struct sctp_auth_bytes *sctp_auth_create_key(__u32 key_len, gfp_t gfp)
+{
+       struct sctp_auth_bytes *key;
+
+       /* Allocate the shared key */
+       key = kmalloc(sizeof(struct sctp_auth_bytes) + key_len, gfp);
+       if (!key)
+               return NULL;
+
+       key->len = key_len;
+       atomic_set(&key->refcnt, 1);
+       SCTP_DBG_OBJCNT_INC(keys);
+
+       return key;
+}
+
+/* Create a new shared key container with a give key id */
+struct sctp_shared_key *sctp_auth_shkey_create(__u16 key_id, gfp_t gfp)
+{
+       struct sctp_shared_key *new;
+
+       /* Allocate the shared key container */
+       new = kzalloc(sizeof(struct sctp_shared_key), gfp);
+       if (!new)
+               return NULL;
+
+       INIT_LIST_HEAD(&new->key_list);
+       new->key_id = key_id;
+
+       return new;
+}
+
+/* Free the shared key stucture */
+void sctp_auth_shkey_free(struct sctp_shared_key *sh_key)
+{
+       BUG_ON(!list_empty(&sh_key->key_list));
+       sctp_auth_key_put(sh_key->key);
+       sh_key->key = NULL;
+       kfree(sh_key);
+}
+
+/* Destory the entire key list.  This is done during the
+ * associon and endpoint free process.
+ */
+void sctp_auth_destroy_keys(struct list_head *keys)
+{
+       struct sctp_shared_key *ep_key;
+       struct sctp_shared_key *tmp;
+
+       if (list_empty(keys))
+               return;
+
+       key_for_each_safe(ep_key, tmp, keys) {
+               list_del_init(&ep_key->key_list);
+               sctp_auth_shkey_free(ep_key);
+       }
+}
+
+/* Compare two byte vectors as numbers.  Return values
+ * are:
+ *       0 - vectors are equal
+ *     < 0 - vector 1 is smaller then vector2
+ *     > 0 - vector 1 is greater then vector2
+ *
+ * Algorithm is:
+ *     This is performed by selecting the numerically smaller key vector...
+ *     If the key vectors are equal as numbers but differ in length ...
+ *     the shorter vector is considered smaller
+ *
+ * Examples (with small values):
+ *     000123456789 > 123456789 (first number is longer)
+ *     000123456789 < 234567891 (second number is larger numerically)
+ *     123456789 > 2345678      (first number is both larger & longer)
+ */
+static int sctp_auth_compare_vectors(struct sctp_auth_bytes *vector1,
+                             struct sctp_auth_bytes *vector2)
+{
+       int diff;
+       int i;
+       const __u8 *longer;
+
+       diff = vector1->len - vector2->len;
+       if (diff) {
+               longer = (diff > 0) ? vector1->data : vector2->data;
+
+               /* Check to see if the longer number is
+                * lead-zero padded.  If it is not, it
+                * is automatically larger numerically.
+                */
+               for (i = 0; i < abs(diff); i++ ) {
+                       if (longer[i] != 0)
+                               return diff;
+               }
+       }
+
+       /* lengths are the same, compare numbers */
+       return memcmp(vector1->data, vector2->data, vector1->len);
+}
+
+/*
+ * Create a key vector as described in SCTP-AUTH, Section 6.1
+ *    The RANDOM parameter, the CHUNKS parameter and the HMAC-ALGO
+ *    parameter sent by each endpoint are concatenated as byte vectors.
+ *    These parameters include the parameter type, parameter length, and
+ *    the parameter value, but padding is omitted; all padding MUST be
+ *    removed from this concatenation before proceeding with further
+ *    computation of keys.  Parameters which were not sent are simply
+ *    omitted from the concatenation process.  The resulting two vectors
+ *    are called the two key vectors.
+ */
+static struct sctp_auth_bytes *sctp_auth_make_key_vector(
+                       sctp_random_param_t *random,
+                       sctp_chunks_param_t *chunks,
+                       sctp_hmac_algo_param_t *hmacs,
+                       gfp_t gfp)
+{
+       struct sctp_auth_bytes *new;
+       __u32   len;
+       __u32   offset = 0;
+
+       len = ntohs(random->param_hdr.length) + ntohs(hmacs->param_hdr.length);
+        if (chunks)
+               len += ntohs(chunks->param_hdr.length);
+
+       new = kmalloc(sizeof(struct sctp_auth_bytes) + len, gfp);
+       if (!new)
+               return NULL;
+
+       new->len = len;
+
+       memcpy(new->data, random, ntohs(random->param_hdr.length));
+       offset += ntohs(random->param_hdr.length);
+
+       if (chunks) {
+               memcpy(new->data + offset, chunks,
+                       ntohs(chunks->param_hdr.length));
+               offset += ntohs(chunks->param_hdr.length);
+       }
+
+       memcpy(new->data + offset, hmacs, ntohs(hmacs->param_hdr.length));
+
+       return new;
+}
+
+
+/* Make a key vector based on our local parameters */
+struct sctp_auth_bytes *sctp_auth_make_local_vector(
+                                   const struct sctp_association *asoc,
+                                   gfp_t gfp)
+{
+       return sctp_auth_make_key_vector(
+                                   (sctp_random_param_t*)asoc->c.auth_random,
+                                   (sctp_chunks_param_t*)asoc->c.auth_chunks,
+                                   (sctp_hmac_algo_param_t*)asoc->c.auth_hmacs,
+                                   gfp);
+}
+
+/* Make a key vector based on peer's parameters */
+struct sctp_auth_bytes *sctp_auth_make_peer_vector(
+                                   const struct sctp_association *asoc,
+                                   gfp_t gfp)
+{
+       return sctp_auth_make_key_vector(asoc->peer.peer_random,
+                                        asoc->peer.peer_chunks,
+                                        asoc->peer.peer_hmacs,
+                                        gfp);
+}
+
+
+/* Set the value of the association shared key base on the parameters
+ * given.  The algorithm is:
+ *    From the endpoint pair shared keys and the key vectors the
+ *    association shared keys are computed.  This is performed by selecting
+ *    the numerically smaller key vector and concatenating it to the
+ *    endpoint pair shared key, and then concatenating the numerically
+ *    larger key vector to that.  The result of the concatenation is the
+ *    association shared key.
+ */
+static struct sctp_auth_bytes *sctp_auth_asoc_set_secret(
+                       struct sctp_shared_key *ep_key,
+                       struct sctp_auth_bytes *first_vector,
+                       struct sctp_auth_bytes *last_vector,
+                       gfp_t gfp)
+{
+       struct sctp_auth_bytes *secret;
+       __u32 offset = 0;
+       __u32 auth_len;
+
+       auth_len = first_vector->len + last_vector->len;
+       if (ep_key->key)
+               auth_len += ep_key->key->len;
+
+       secret = sctp_auth_create_key(auth_len, gfp);
+       if (!secret)
+               return NULL;
+
+       if (ep_key->key) {
+               memcpy(secret->data, ep_key->key->data, ep_key->key->len);
+               offset += ep_key->key->len;
+       }
+
+       memcpy(secret->data + offset, first_vector->data, first_vector->len);
+       offset += first_vector->len;
+
+       memcpy(secret->data + offset, last_vector->data, last_vector->len);
+
+       return secret;
+}
+
+/* Create an association shared key.  Follow the algorithm
+ * described in SCTP-AUTH, Section 6.1
+ */
+static struct sctp_auth_bytes *sctp_auth_asoc_create_secret(
+                                const struct sctp_association *asoc,
+                                struct sctp_shared_key *ep_key,
+                                gfp_t gfp)
+{
+       struct sctp_auth_bytes *local_key_vector;
+       struct sctp_auth_bytes *peer_key_vector;
+       struct sctp_auth_bytes  *first_vector,
+                               *last_vector;
+       struct sctp_auth_bytes  *secret = NULL;
+       int     cmp;
+
+
+       /* Now we need to build the key vectors
+        * SCTP-AUTH , Section 6.1
+        *    The RANDOM parameter, the CHUNKS parameter and the HMAC-ALGO
+        *    parameter sent by each endpoint are concatenated as byte vectors.
+        *    These parameters include the parameter type, parameter length, and
+        *    the parameter value, but padding is omitted; all padding MUST be
+        *    removed from this concatenation before proceeding with further
+        *    computation of keys.  Parameters which were not sent are simply
+        *    omitted from the concatenation process.  The resulting two vectors
+        *    are called the two key vectors.
+        */
+
+       local_key_vector = sctp_auth_make_local_vector(asoc, gfp);
+       peer_key_vector = sctp_auth_make_peer_vector(asoc, gfp);
+
+       if (!peer_key_vector || !local_key_vector)
+               goto out;
+
+       /* Figure out the order in wich the key_vectors will be
+        * added to the endpoint shared key.
+        * SCTP-AUTH, Section 6.1:
+        *   This is performed by selecting the numerically smaller key
+        *   vector and concatenating it to the endpoint pair shared
+        *   key, and then concatenating the numerically larger key
+        *   vector to that.  If the key vectors are equal as numbers
+        *   but differ in length, then the concatenation order is the
+        *   endpoint shared key, followed by the shorter key vector,
+        *   followed by the longer key vector.  Otherwise, the key
+        *   vectors are identical, and may be concatenated to the
+        *   endpoint pair key in any order.
+        */
+       cmp = sctp_auth_compare_vectors(local_key_vector,
+                                       peer_key_vector);
+       if (cmp < 0) {
+               first_vector = local_key_vector;
+               last_vector = peer_key_vector;
+       } else {
+               first_vector = peer_key_vector;
+               last_vector = local_key_vector;
+       }
+
+       secret = sctp_auth_asoc_set_secret(ep_key, first_vector, last_vector,
+                                           gfp);
+out:
+       kfree(local_key_vector);
+       kfree(peer_key_vector);
+
+       return secret;
+}
+
+/*
+ * Populate the association overlay list with the list
+ * from the endpoint.
+ */
+int sctp_auth_asoc_copy_shkeys(const struct sctp_endpoint *ep,
+                               struct sctp_association *asoc,
+                               gfp_t gfp)
+{
+       struct sctp_shared_key *sh_key;
+       struct sctp_shared_key *new;
+
+       BUG_ON(!list_empty(&asoc->endpoint_shared_keys));
+
+       key_for_each(sh_key, &ep->endpoint_shared_keys) {
+               new = sctp_auth_shkey_create(sh_key->key_id, gfp);
+               if (!new)
+                       goto nomem;
+
+               new->key = sh_key->key;
+               sctp_auth_key_hold(new->key);
+               list_add(&new->key_list, &asoc->endpoint_shared_keys);
+       }
+
+       return 0;
+
+nomem:
+       sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
+       return -ENOMEM;
+}
+
+
+/* Public interface to creat the association shared key.
+ * See code above for the algorithm.
+ */
+int sctp_auth_asoc_init_active_key(struct sctp_association *asoc, gfp_t gfp)
+{
+       struct sctp_auth_bytes  *secret;
+       struct sctp_shared_key *ep_key;
+
+       /* If we don't support AUTH, or peer is not capable
+        * we don't need to do anything.
+        */
+       if (!sctp_auth_enable || !asoc->peer.auth_capable)
+               return 0;
+
+       /* If the key_id is non-zero and we couldn't find an
+        * endpoint pair shared key, we can't compute the
+        * secret.
+        * For key_id 0, endpoint pair shared key is a NULL key.
+        */
+       ep_key = sctp_auth_get_shkey(asoc, asoc->active_key_id);
+       BUG_ON(!ep_key);
+
+       secret = sctp_auth_asoc_create_secret(asoc, ep_key, gfp);
+       if (!secret)
+               return -ENOMEM;
+
+       sctp_auth_key_put(asoc->asoc_shared_key);
+       asoc->asoc_shared_key = secret;
+
+       return 0;
+}
+
+
+/* Find the endpoint pair shared key based on the key_id */
+struct sctp_shared_key *sctp_auth_get_shkey(
+                               const struct sctp_association *asoc,
+                               __u16 key_id)
+{
+       struct sctp_shared_key *key = NULL;
+
+       /* First search associations set of endpoint pair shared keys */
+       key_for_each(key, &asoc->endpoint_shared_keys) {
+               if (key->key_id == key_id)
+                       break;
+       }
+
+       return key;
+}
+
+/*
+ * Initialize all the possible digest transforms that we can use.  Right now
+ * now, the supported digests are SHA1 and SHA256.  We do this here once
+ * because of the restrictiong that transforms may only be allocated in
+ * user context.  This forces us to pre-allocated all possible transforms
+ * at the endpoint init time.
+ */
+int sctp_auth_init_hmacs(struct sctp_endpoint *ep, gfp_t gfp)
+{
+       struct crypto_hash *tfm = NULL;
+       __u16   id;
+
+       /* if the transforms are already allocted, we are done */
+       if (!sctp_auth_enable) {
+               ep->auth_hmacs = NULL;
+               return 0;
+       }
+
+       if (ep->auth_hmacs)
+               return 0;
+
+       /* Allocated the array of pointers to transorms */
+       ep->auth_hmacs = kzalloc(
+                           sizeof(struct crypto_hash *) * SCTP_AUTH_NUM_HMACS,
+                           gfp);
+       if (!ep->auth_hmacs)
+               return -ENOMEM;
+
+       for (id = 0; id < SCTP_AUTH_NUM_HMACS; id++) {
+
+               /* See is we support the id.  Supported IDs have name and
+                * length fields set, so that we can allocated and use
+                * them.  We can safely just check for name, for without the
+                * name, we can't allocate the TFM.
+                */
+               if (!sctp_hmac_list[id].hmac_name)
+                       continue;
+
+               /* If this TFM has been allocated, we are all set */
+               if (ep->auth_hmacs[id])
+                       continue;
+
+               /* Allocate the ID */
+               tfm = crypto_alloc_hash(sctp_hmac_list[id].hmac_name, 0,
+                                       CRYPTO_ALG_ASYNC);
+               if (IS_ERR(tfm))
+                       goto out_err;
+
+               ep->auth_hmacs[id] = tfm;
+       }
+
+       return 0;
+
+out_err:
+       /* Clean up any successfull allocations */
+       sctp_auth_destroy_hmacs(ep->auth_hmacs);
+       return -ENOMEM;
+}
+
+/* Destroy the hmac tfm array */
+void sctp_auth_destroy_hmacs(struct crypto_hash *auth_hmacs[])
+{
+       int i;
+
+       if (!auth_hmacs)
+               return;
+
+       for (i = 0; i < SCTP_AUTH_NUM_HMACS; i++)
+       {
+               if (auth_hmacs[i])
+                       crypto_free_hash(auth_hmacs[i]);
+       }
+       kfree(auth_hmacs);
+}
+
+
+struct sctp_hmac *sctp_auth_get_hmac(__u16 hmac_id)
+{
+       return &sctp_hmac_list[hmac_id];
+}
+
+/* Get an hmac description information that we can use to build
+ * the AUTH chunk
+ */
+struct sctp_hmac *sctp_auth_asoc_get_hmac(const struct sctp_association *asoc)
+{
+       struct sctp_hmac_algo_param *hmacs;
+       __u16 n_elt;
+       __u16 id = 0;
+       int i;
+
+       /* If we have a default entry, use it */
+       if (asoc->default_hmac_id)
+               return &sctp_hmac_list[asoc->default_hmac_id];
+
+       /* Since we do not have a default entry, find the first entry
+        * we support and return that.  Do not cache that id.
+        */
+       hmacs = asoc->peer.peer_hmacs;
+       if (!hmacs)
+               return NULL;
+
+       n_elt = (ntohs(hmacs->param_hdr.length) - sizeof(sctp_paramhdr_t)) >> 1;
+       for (i = 0; i < n_elt; i++) {
+               id = ntohs(hmacs->hmac_ids[i]);
+
+               /* Check the id is in the supported range */
+               if (id > SCTP_AUTH_HMAC_ID_MAX)
+                       continue;
+
+               /* See is we support the id.  Supported IDs have name and
+                * length fields set, so that we can allocated and use
+                * them.  We can safely just check for name, for without the
+                * name, we can't allocate the TFM.
+                */
+               if (!sctp_hmac_list[id].hmac_name)
+                       continue;
+
+               break;
+       }
+
+       if (id == 0)
+               return NULL;
+
+       return &sctp_hmac_list[id];
+}
+
+static int __sctp_auth_find_hmacid(__u16 *hmacs, int n_elts, __u16 hmac_id)
+{
+       int  found = 0;
+       int  i;
+
+       for (i = 0; i < n_elts; i++) {
+               if (hmac_id == hmacs[i]) {
+                       found = 1;
+                       break;
+               }
+       }
+
+       return found;
+}
+
+/* See if the HMAC_ID is one that we claim as supported */
+int sctp_auth_asoc_verify_hmac_id(const struct sctp_association *asoc,
+                                   __u16 hmac_id)
+{
+       struct sctp_hmac_algo_param *hmacs;
+       __u16 n_elt;
+
+       if (!asoc)
+               return 0;
+
+       hmacs = (struct sctp_hmac_algo_param *)asoc->c.auth_hmacs;
+       n_elt = (ntohs(hmacs->param_hdr.length) - sizeof(sctp_paramhdr_t)) >> 1;
+
+       return __sctp_auth_find_hmacid(hmacs->hmac_ids, n_elt, hmac_id);
+}
+
+
+/* Cache the default HMAC id.  This to follow this text from SCTP-AUTH:
+ * Section 6.1:
+ *   The receiver of a HMAC-ALGO parameter SHOULD use the first listed
+ *   algorithm it supports.
+ */
+void sctp_auth_asoc_set_default_hmac(struct sctp_association *asoc,
+                                    struct sctp_hmac_algo_param *hmacs)
+{
+       struct sctp_endpoint *ep;
+       __u16   id;
+       int     i;
+       int     n_params;
+
+       /* if the default id is already set, use it */
+       if (asoc->default_hmac_id)
+               return;
+
+       n_params = (ntohs(hmacs->param_hdr.length)
+                               - sizeof(sctp_paramhdr_t)) >> 1;
+       ep = asoc->ep;
+       for (i = 0; i < n_params; i++) {
+               id = ntohs(hmacs->hmac_ids[i]);
+
+               /* Check the id is in the supported range */
+               if (id > SCTP_AUTH_HMAC_ID_MAX)
+                       continue;
+
+               /* If this TFM has been allocated, use this id */
+               if (ep->auth_hmacs[id]) {
+                       asoc->default_hmac_id = id;
+                       break;
+               }
+       }
+}
+
+
+/* Check to see if the given chunk is supposed to be authenticated */
+static int __sctp_auth_cid(sctp_cid_t chunk, struct sctp_chunks_param *param)
+{
+       unsigned short len;
+       int found = 0;
+       int i;
+
+       if (!param)
+               return 0;
+
+       len = ntohs(param->param_hdr.length) - sizeof(sctp_paramhdr_t);
+
+       /* SCTP-AUTH, Section 3.2
+        *    The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH
+        *    chunks MUST NOT be listed in the CHUNKS parameter.  However, if
+        *    a CHUNKS parameter is received then the types for INIT, INIT-ACK,
+        *    SHUTDOWN-COMPLETE and AUTH chunks MUST be ignored.
+        */
+       for (i = 0; !found && i < len; i++) {
+               switch (param->chunks[i]) {
+                   case SCTP_CID_INIT:
+                   case SCTP_CID_INIT_ACK:
+                   case SCTP_CID_SHUTDOWN_COMPLETE:
+                   case SCTP_CID_AUTH:
+                       break;
+
+                   default:
+                       if (param->chunks[i] == chunk)
+                           found = 1;
+                       break;
+               }
+       }
+
+       return found;
+}
+
+/* Check if peer requested that this chunk is authenticated */
+int sctp_auth_send_cid(sctp_cid_t chunk, const struct sctp_association *asoc)
+{
+       if (!sctp_auth_enable || !asoc || !asoc->peer.auth_capable)
+               return 0;
+
+       return __sctp_auth_cid(chunk, asoc->peer.peer_chunks);
+}
+
+/* Check if we requested that peer authenticate this chunk. */
+int sctp_auth_recv_cid(sctp_cid_t chunk, const struct sctp_association *asoc)
+{
+       if (!sctp_auth_enable || !asoc)
+               return 0;
+
+       return __sctp_auth_cid(chunk,
+                             (struct sctp_chunks_param *)asoc->c.auth_chunks);
+}
+
+/* SCTP-AUTH: Section 6.2:
+ *    The sender MUST calculate the MAC as described in RFC2104 [2] using
+ *    the hash function H as described by the MAC Identifier and the shared
+ *    association key K based on the endpoint pair shared key described by
+ *    the shared key identifier.  The 'data' used for the computation of
+ *    the AUTH-chunk is given by the AUTH chunk with its HMAC field set to
+ *    zero (as shown in Figure 6) followed by all chunks that are placed
+ *    after the AUTH chunk in the SCTP packet.
+ */
+void sctp_auth_calculate_hmac(const struct sctp_association *asoc,
+                             struct sk_buff *skb,
+                             struct sctp_auth_chunk *auth,
+                             gfp_t gfp)
+{
+       struct scatterlist sg;
+       struct hash_desc desc;
+       struct sctp_auth_bytes *asoc_key;
+       __u16 key_id, hmac_id;
+       __u8 *digest;
+       unsigned char *end;
+       int free_key = 0;
+
+       /* Extract the info we need:
+        * - hmac id
+        * - key id
+        */
+       key_id = ntohs(auth->auth_hdr.shkey_id);
+       hmac_id = ntohs(auth->auth_hdr.hmac_id);
+
+       if (key_id == asoc->active_key_id)
+               asoc_key = asoc->asoc_shared_key;
+       else {
+               struct sctp_shared_key *ep_key;
+
+               ep_key = sctp_auth_get_shkey(asoc, key_id);
+               if (!ep_key)
+                       return;
+
+               asoc_key = sctp_auth_asoc_create_secret(asoc, ep_key, gfp);
+               if (!asoc_key)
+                       return;
+
+               free_key = 1;
+       }
+
+       /* set up scatter list */
+       end = skb_tail_pointer(skb);
+       sg.page = virt_to_page(auth);
+       sg.offset = (unsigned long)(auth) % PAGE_SIZE;
+       sg.length = end - (unsigned char *)auth;
+
+       desc.tfm = asoc->ep->auth_hmacs[hmac_id];
+       desc.flags = 0;
+
+       digest = auth->auth_hdr.hmac;
+       if (crypto_hash_setkey(desc.tfm, &asoc_key->data[0], asoc_key->len))
+               goto free;
+
+       crypto_hash_digest(&desc, &sg, sg.length, digest);
+
+free:
+       if (free_key)
+               sctp_auth_key_put(asoc_key);
+}
diff --git a/net/sctp/objcnt.c b/net/sctp/objcnt.c
index fcfb9d8..2cf6ad6 100644
--- a/net/sctp/objcnt.c
+++ b/net/sctp/objcnt.c
@@ -58,6 +58,7 @@ SCTP_DBG_OBJCNT(chunk);
 SCTP_DBG_OBJCNT(addr);
 SCTP_DBG_OBJCNT(ssnmap);
 SCTP_DBG_OBJCNT(datamsg);
+SCTP_DBG_OBJCNT(keys);
 
 /* An array to make it easy to pretty print the debug information
  * to the proc fs.
@@ -73,6 +74,7 @@ static sctp_dbg_objcnt_entry_t sctp_dbg_objcnt[] = {
        SCTP_DBG_OBJCNT_ENTRY(addr),
        SCTP_DBG_OBJCNT_ENTRY(ssnmap),
        SCTP_DBG_OBJCNT_ENTRY(datamsg),
+       SCTP_DBG_OBJCNT_ENTRY(keys),
 };
 
 /* Callback from procfs to read out objcount information.
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to