X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/tripe/blobdiff_plain/c511e1f925da3e735fb494d522ae3ae0f17ab9ce..6411163d48434575eaf49463e056e971a2fba16a:/server/tripe.h diff --git a/server/tripe.h b/server/tripe.h index a9a785dc..8a0be518 100644 --- a/server/tripe.h +++ b/server/tripe.h @@ -1,13 +1,11 @@ /* -*-c-*- - * - * $Id$ * * Main header file for TrIPE * * (c) 2001 Straylight/Edgeware */ -/*----- Licensing notice --------------------------------------------------* +/*----- Licensing notice --------------------------------------------------* * * This file is part of Trivial IP Encryption (TrIPE). * @@ -15,12 +13,12 @@ * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. - * + * * TrIPE 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 TrIPE; if not, write to the Free Software Foundation, * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. @@ -54,6 +52,7 @@ #include #include #include +#include #include #include @@ -68,10 +67,15 @@ #include #include #include +#include #include #include #include +#include #include +#include +#include +#include #include #include #include @@ -82,6 +86,7 @@ #include #include #include +#include #include @@ -101,7 +106,9 @@ #include #include +#include "priv.h" #include "protocol.h" +#include "slip.h" #include "util.h" #undef sun @@ -119,8 +126,9 @@ #define T_KEYEXCH 64u #define T_KEYMGMT 128u #define T_CHAL 256u +/* T_PRIVSEP in priv.h */ -#define T_ALL 511u +#define T_ALL 1023u /* --- Units --- */ @@ -141,6 +149,7 @@ typedef struct algswitch { const gcmac *m; /* Message authentication code */ size_t hashsz; /* Hash output size */ size_t tagsz; /* Length to truncate MAC tags */ + size_t expsz; /* Size of data to process */ size_t cksz, mksz; /* Key lengths for @c@ and @m@ */ } algswitch; @@ -162,6 +171,18 @@ typedef union addr { struct sockaddr_in sin; } addr; +/* --- Mapping keyed on addresses --- */ + +typedef struct addrmap { + hash_table t; + size_t load; +} addrmap; + +typedef struct addrmap_base { + hash_base b; + addr a; +} addrmap_base; + /* --- Sequence number checking --- */ typedef struct seqwin { @@ -189,12 +210,12 @@ typedef struct keyset { unsigned ref; /* Reference count for keyset */ struct peer *p; /* Pointer to peer structure */ time_t t_exp; /* Expiry time for this keyset */ - unsigned long sz_exp; /* Data limit for the keyset */ + unsigned long sz_exp, sz_regen; /* Data limits for the keyset */ T( unsigned seq; ) /* Sequence number for tracing */ unsigned f; /* Various useful flags */ - gcipher *cin, *cout; /* Keyset ciphers for encryption */ + gcipher *cin, *cout; /* Keyset ciphers for encryption */ size_t tagsz; /* Length to truncate MAC tags */ - gmac *min, *mout; /* Keyset MACs for integrity */ + gmac *min, *mout; /* Keyset MACs for integrity */ uint32 oseq; /* Outbound sequence number */ seqwin iseq; /* Inbound sequence number */ } keyset; @@ -202,6 +223,12 @@ typedef struct keyset { #define KSF_LISTEN 1u /* Don't encrypt packets yet */ #define KSF_LINK 2u /* Key is in a linked list */ +#define KSERR_REGEN -1 /* Regenerate keys */ +#define KSERR_NOKEYS -2 /* No keys left */ +#define KSERR_DECRYPT -3 /* Unable to decrypt message */ +#define KSERR_SEQ -4 /* Incorrect sequence number */ +#define KSERR_MALFORMED -5 /* Input ciphertext is broken */ + /* --- Key exchange --- * * * TrIPE uses the Wrestlers Protocol for its key exchange. The Wrestlers @@ -248,6 +275,7 @@ typedef struct keyexch { #define KXF_TIMER 1u /* Waiting for a timer to go off */ #define KXF_DEAD 2u /* The key-exchanger isn't up */ #define KXF_PUBKEY 4u /* Key exchanger has a public key */ +#define KXF_CORK 8u /* Don't send anything yet */ enum { KXS_DEAD, /* Uninitialized state (magical) */ @@ -266,9 +294,13 @@ struct peer; typedef struct tunnel_ops { const char *name; /* Name of this tunnel driver */ + unsigned flags; /* Various interesting flags */ +#define TUNF_PRIVOPEN 1u /* Need helper to open file */ void (*init)(void); /* Initializes the system */ - tunnel *(*create)(struct peer */*p*/); /* Initializes a new tunnel */ - const char *(*ifname)(tunnel */*t*/); /* Returns tunnel's interface name */ + tunnel *(*create)(struct peer */*p*/, int /*fd*/, char **/*ifn*/); + /* Initializes a new tunnel */ + void (*setifname)(tunnel */*t*/, const char */*ifn*/); + /* Notifies ifname change */ void (*inject)(tunnel */*t*/, buf */*b*/); /* Sends packet through if */ void (*destroy)(tunnel */*t*/); /* Destroys a tunnel */ } tunnel_ops; @@ -303,14 +335,29 @@ typedef struct stats { typedef struct peerspec { char *name; /* Peer's name */ + char *tag; /* Public key tag */ const tunnel_ops *tops; /* Tunnel operations */ unsigned long t_ka; /* Keep alive interval */ addr sa; /* Socket address to speak to */ size_t sasz; /* Socket address size */ + unsigned f; /* Flags for the peer */ +#define PSF_KXMASK 255u /* Key-exchange flags to set */ +#define PSF_MOBILE 256u /* Address may change rapidly */ } peerspec; +typedef struct peer_byname { + sym_base _b; + struct peer *p; +} peer_byname; + +typedef struct peer_byaddr { + addrmap_base _b; + struct peer *p; +} peer_byaddr; + typedef struct peer { - struct peer *next, *prev; /* Links to next and previous */ + peer_byname *byname; /* Lookup-by-name block */ + peer_byaddr *byaddr; /* Lookup-by-address block */ struct ping *pings; /* Pings we're waiting for */ peerspec spec; /* Specifications for this peer */ tunnel *t; /* Tunnel for local packets */ @@ -322,6 +369,8 @@ typedef struct peer { sel_timer tka; /* Timer for keepalives */ } peer; +typedef struct peer_iter { sym_iter i; } peer_iter; + typedef struct ping { struct ping *next, *prev; /* Links to next and previous */ peer *p; /* Peer so we can free it */ @@ -381,17 +430,40 @@ typedef struct admin_addop { peerspec peer; /* Peer pending creation */ } admin_addop; -typedef struct admin_greetop { - admin_resop r; /* Name resolution header */ - void *c; /* Challenge block */ - size_t sz; /* Length of challenge */ -} admin_greetop; - typedef struct admin_pingop { admin_bgop bg; /* Background operation header */ ping ping; /* Ping pending response */ struct timeval pingtime; /* Time last ping was sent */ -} admin_pingop; +} admin_pingop; + +typedef struct admin_service { + sym_base _b; /* Hash table base structure */ + char *version; /* The provided version */ + struct admin *prov; /* Which client provides me */ + struct admin_service *next, *prev; /* Client's list of services */ +} admin_service; + +typedef struct admin_svcop { + admin_bgop bg; /* Background operation header */ + struct admin *prov; /* Client servicing this job */ + unsigned index; /* This job's index */ + struct admin_svcop *next, *prev; /* Links for provider's jobs */ +} admin_svcop; + +typedef struct admin_jobentry { + unsigned short seq; /* Zero if unused */ + union { + admin_svcop *op; /* Operation, if slot in use, ... */ + uint32 next; /* ... or index of next free slot */ + } u; +} admin_jobentry; + +typedef struct admin_jobtable { + uint32 n, sz; /* Used slots and table size */ + admin_svcop *active; /* List of active jobs */ + uint32 free; /* Index of first free slot */ + admin_jobentry *v; /* And the big array of entries */ +} admin_jobtable; typedef struct admin { struct admin *next, *prev; /* Links to next and previous */ @@ -403,6 +475,8 @@ typedef struct admin { oqueue out; /* Output buffer list */ oqueue delay; /* Delayed output buffer list */ admin_bgop *bg; /* Backgrounded operations */ + admin_service *svcs; /* Which services I provide */ + admin_jobtable j; /* Table of outstanding jobs */ selbuf b; /* Line buffer for commands */ sel_file w; /* Selector for write buffering */ } admin; @@ -414,6 +488,7 @@ typedef struct admin { #ifndef NTRACE #define AF_TRACE 16u /* Catch tracing */ #endif +#define AF_FOREGROUND 32u /* Quit server when client closes */ #ifndef NTRACE # define AF_ALLMSGS (AF_NOTE | AF_TRACE | AF_WARN) @@ -428,7 +503,7 @@ extern group *gg; /* The group we work in */ extern size_t indexsz; /* Size of exponent for the group */ extern mp *kpriv; /* Our private key */ extern ge *kpub; /* Our public key */ -extern octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ]; +extern octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ], buf_u[PKBUFSZ]; extern const tunnel_ops *tunnels[]; /* Table of tunnels (0-term) */ extern const tunnel_ops *tun_default; /* Default tunnel to use */ @@ -542,6 +617,7 @@ extern void kx_newkeys(keyexch */*kx*/); * Arguments: @keyexch *kx@ = pointer to key exchange context * @peer *p@ = pointer to peer context * @keyset **ks@ = pointer to keyset list + * @unsigned f@ = various useful flags * * Returns: Zero if OK, nonzero if it failed. * @@ -550,7 +626,8 @@ extern void kx_newkeys(keyexch */*kx*/); * exchange. */ -extern int kx_init(keyexch */*kx*/, peer */*p*/, keyset **/*ks*/); +extern int kx_init(keyexch */*kx*/, peer */*p*/, + keyset **/*ks*/, unsigned /*f*/); /*----- Keysets and symmetric cryptography --------------------------------*/ @@ -621,9 +698,10 @@ extern void ks_activate(keyset */*ks*/); * @buf *b@ = pointer to input buffer * @buf *bb@ = pointer to output buffer * - * Returns: Zero if OK, nonzero if the key needs replacing. If the - * encryption failed, the output buffer is broken and zero is - * returned. + * Returns: Zero if successful; @KSERR_REGEN@ if we should negotiate a + * new key; @KSERR_NOKEYS@ if the key is not usable. Also + * returns zero if there was insufficient buffer (but the output + * buffer is broken in this case). * * Use: Encrypts a block of data using the key. Note that the `key * ought to be replaced' notification is only ever given once @@ -641,7 +719,9 @@ extern int ks_encrypt(keyset */*ks*/, unsigned /*ty*/, * @buf *b@ = pointer to an input buffer * @buf *bb@ = pointer to an output buffer * - * Returns: Zero on success, or nonzero if there was some problem. + * Returns: Zero on success; @KSERR_DECRYPT@ on failure. Also returns + * zero if there was insufficient buffer (but the output buffer + * is broken in this case). * * Use: Attempts to decrypt a message using a given key. Note that * requesting decryption with a key directly won't clear a @@ -694,7 +774,10 @@ extern void ksl_prune(keyset **/*ksroot*/); * @buf *b@ = pointer to input buffer * @buf *bb@ = pointer to output buffer * - * Returns: Nonzero if a new key is needed. + * Returns: Zero if successful; @KSERR_REGEN@ if it's time to negotiate a + * new key; @KSERR_NOKEYS@ if there are no suitable keys + * available. Also returns zero if there was insufficient + * buffer space (but the output buffer is broken in this case). * * Use: Encrypts a packet. */ @@ -709,7 +792,9 @@ extern int ksl_encrypt(keyset **/*ksroot*/, unsigned /*ty*/, * @buf *b@ = pointer to input buffer * @buf *bb@ = pointer to output buffer * - * Returns: Nonzero if the packet couldn't be decrypted. + * Returns: Zero on success; @KSERR_DECRYPT@ on failure. Also returns + * zero if there was insufficient buffer (but the output buffer + * is broken in this case). * * Use: Decrypts a packet. */ @@ -745,6 +830,37 @@ extern int c_check(buf */*b*/); #define A_END ((char *)0) +/* --- @a_vformat@ --- * + * + * Arguments: @dstr *d@ = where to leave the formatted message + * @const char *fmt@ = pointer to format string + * @va_list ap@ = arguments in list + * + * Returns: --- + * + * Use: Main message token formatting driver. The arguments are + * interleaved formatting tokens and their parameters, finally + * terminated by an entry @A_END@. + * + * Tokens recognized: + * + * * "*..." ... -- pretokenized @dstr_putf@-like string + * + * * "?ADDR" SOCKADDR -- a socket address, to be converted + * + * * "?B64" BUFFER SIZE -- binary data to be base64-encoded + * + * * "?TOKENS" VECTOR -- null-terminated vector of tokens + * + * * "?PEER" PEER -- peer's name + * + * * "?ERRNO" ERRNO -- system error code + * + * * "[!]..." ... -- @dstr_putf@-like string as single token + */ + +extern void a_vformat(dstr */*d*/, const char */*fmt*/, va_list /*ap*/); + /* --- @a_warn@ --- * * * Arguments: @const char *fmt@ = pointer to format string @@ -819,13 +935,133 @@ extern void a_daemon(void); /* --- @a_init@ --- * * * Arguments: @const char *sock@ = socket name to create + * @uid_t u@ = user to own the socket + * @gid_t g@ = group to own the socket + * @mode_t m@ = permissions to set on the socket * * Returns: --- * * Use: Creates the admin listening socket. */ -extern void a_init(const char */*sock*/); +extern void a_init(const char */*sock*/, + uid_t /*u*/, gid_t /*g*/, mode_t /*m*/); + +/*----- Mapping with addresses as keys ------------------------------------*/ + +/* --- @am_create@ --- * + * + * Arguments: @addrmap *m@ = pointer to map + * + * Returns: --- + * + * Use: Create an address map, properly set up. + */ + +extern void am_create(addrmap */*m*/); + +/* --- @am_destroy@ --- * + * + * Arguments: @addrmap *m@ = pointer to map + * + * Returns: --- + * + * Use: Destroy an address map, throwing away all the entries. + */ + +extern void am_destroy(addrmap */*m*/); + +/* --- @am_find@ --- * + * + * Arguments: @addrmap *m@ = pointer to map + * @const addr *a@ = address to look up + * @size_t sz@ = size of block to allocate + * @unsigned *f@ = where to store flags + * + * Returns: Pointer to found item, or null. + * + * Use: Finds a record with the given IP address, set @*f@ nonzero + * and returns it. If @sz@ is zero, and no match was found, + * return null; otherwise allocate a new block of @sz@ bytes, + * clear @*f@ to zero and return the block pointer. + */ + +extern void *am_find(addrmap */*m*/, const addr */*a*/, + size_t /*sz*/, unsigned */*f*/); + +/* --- @am_remove@ --- * + * + * Arguments: @addrmap *m@ = pointer to map + * @void *i@ = pointer to the item + * + * Returns: --- + * + * Use: Removes an item from the map. + */ + +extern void am_remove(addrmap */*m*/, void */*i*/); + +/*----- Privilege separation ----------------------------------------------*/ + +/* --- @ps_trace@ --- * + * + * Arguments: @unsigned mask@ = trace mask to check + * @const char *fmt@ = message format + * @...@ = values for placeholders + * + * Returns: --- + * + * Use: Writes a trace message. + */ + +T( extern void ps_trace(unsigned /*mask*/, const char */*fmt*/, ...); ) + +/* --- @ps_warn@ --- * + * + * Arguments: @const char *fmt@ = message format + * @...@ = values for placeholders + * + * Returns: --- + * + * Use: Writes a warning message. + */ + +extern void ps_warn(const char */*fmt*/, ...); + +/* --- @ps_tunfd@ --- * + * + * Arguments: @const tunnel_ops *tops@ = pointer to tunnel operations + * @char **ifn@ = where to put the interface name + * + * Returns: The file descriptor, or @-1@ on error. + * + * Use: Fetches a file descriptor for a tunnel driver. + */ + +extern int ps_tunfd(const tunnel_ops */*tops*/, char **/*ifn*/); + +/* --- @ps_split@ --- * + * + * Arguments: @int detachp@ = whether to detach the child from its terminal + * + * Returns: --- + * + * Use: Separates off the privileged tunnel-opening service from the + * rest of the server. + */ + +extern void ps_split(int /*detachp*/); + +/* --- @ps_quit@ --- * + * + * Arguments: --- + * + * Returns: --- + * + * Use: Detaches from the helper process. + */ + +extern void ps_quit(void); /*----- Peer management ---------------------------------------------------*/ @@ -1014,6 +1250,15 @@ extern peer *p_create(peerspec */*spec*/); extern const char *p_name(peer */*p*/); +/* --- @p_tag@ --- * + * + * Arguments: @peer *p@ = pointer to a peer block + * + * Returns: A pointer to the peer's public key tag. + */ + +extern const char *p_tag(peer */*p*/); + /* --- @p_spec@ --- * * * Arguments: @peer *p@ = pointer to a peer block @@ -1023,6 +1268,17 @@ extern const char *p_name(peer */*p*/); extern const peerspec *p_spec(peer */*p*/); +/* --- @p_findbyaddr@ --- * + * + * Arguments: @const addr *a@ = address to look up + * + * Returns: Pointer to the peer block, or null if not found. + * + * Use: Finds a peer by address. + */ + +extern peer *p_findbyaddr(const addr */*a*/); + /* --- @p_find@ --- * * * Arguments: @const char *name@ = name to look up @@ -1045,17 +1301,41 @@ extern peer *p_find(const char */*name*/); extern void p_destroy(peer */*p*/); -/* --- @p_first@, @p_next@ --- * +/* --- @FOREACH_PEER@ --- * + * + * Arguments: @p@ = name to bind to each peer + * @stuff@ = thing to do for each item + * + * Use: Does something for each current peer. + */ + +#define FOREACH_PEER(p, stuff) do { \ + peer_iter i_; \ + peer *p; \ + for (p_mkiter(&i_); (p = p_next(&i_)) != 0; ) stuff \ +} while (0) + +/* --- @p_mkiter@ --- * + * + * Arguments: @peer_iter *i@ = pointer to an iterator + * + * Returns: --- + * + * Use: Initializes the iterator. + */ + +extern void p_mkiter(peer_iter */*i*/); + +/* --- @p_next@ --- * + * + * Arguments: @peer_iter *i@ = pointer to an iterator * - * Arguments: @peer *p@ = a peer block + * Returns: Next peer, or null if at the end. * - * Returns: @peer_first@ returns the first peer in some ordering; - * @peer_next@ returns the peer following a given one in the - * same ordering. Null is returned for the end of the list. + * Use: Returns the next peer. */ -extern peer *p_first(void); -extern peer *p_next(peer */*p*/); +extern peer *p_next(peer_iter */*i*/); /*----- Tunnel drivers ----------------------------------------------------*/ @@ -1082,7 +1362,7 @@ extern const tunnel_ops tun_slip; * Returns: A pointer to the integer's textual representation. * * Use: Converts a multiprecision integer to a string. Corrupts - * @buf_t@. + * @buf_u@. */ extern const char *mpstr(mp */*m*/); @@ -1095,7 +1375,7 @@ extern const char *mpstr(mp */*m*/); * Returns: A pointer to the element's textual representation. * * Use: Converts a group element to a string. Corrupts - * @buf_t@. + * @buf_u@. */ extern const char *gestr(group */*g*/, ge */*x*/); @@ -1107,7 +1387,7 @@ extern const char *gestr(group */*g*/, ge */*x*/); * Returns: A pointer to a textual representation of the time. * * Use: Converts a time to a textual representation. Corrupts - * @buf_t@. + * @buf_u@. */ extern const char *timestr(time_t /*t*/);