X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/tripe/blobdiff_plain/c8e02c8a4947afa4f9ac20e78a3c8808b3945804..6411163d48434575eaf49463e056e971a2fba16a:/server/tripe.h diff --git a/server/tripe.h b/server/tripe.h index bf599774..8a0be518 100644 --- a/server/tripe.h +++ b/server/tripe.h @@ -52,6 +52,7 @@ #include #include #include +#include #include #include @@ -70,9 +71,11 @@ #include #include #include +#include #include #include #include +#include #include #include #include @@ -103,7 +106,9 @@ #include #include +#include "priv.h" #include "protocol.h" +#include "slip.h" #include "util.h" #undef sun @@ -121,8 +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 --- */ @@ -143,6 +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; @@ -203,7 +210,7 @@ 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 */ @@ -216,6 +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 @@ -281,8 +294,10 @@ 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*/, char **/*ifn*/); + tunnel *(*create)(struct peer */*p*/, int /*fd*/, char **/*ifn*/); /* Initializes a new tunnel */ void (*setifname)(tunnel */*t*/, const char */*ifn*/); /* Notifies ifname change */ @@ -320,11 +335,14 @@ 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 kxf; /* Key exchange flags to set */ + 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 { @@ -412,12 +430,6 @@ 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 */ @@ -434,7 +446,7 @@ typedef struct admin_service { typedef struct admin_svcop { admin_bgop bg; /* Background operation header */ struct admin *prov; /* Client servicing this job */ - unsigned short index; /* This job's index */ + unsigned index; /* This job's index */ struct admin_svcop *next, *prev; /* Links for provider's jobs */ } admin_svcop; @@ -476,6 +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) @@ -490,7 +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 */ @@ -685,9 +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 @@ -705,7 +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 @@ -758,7 +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. */ @@ -773,7 +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. */ @@ -809,6 +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 @@ -883,13 +935,17 @@ 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 ------------------------------------*/ @@ -945,6 +1001,68 @@ extern void *am_find(addrmap */*m*/, const addr */*a*/, 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 ---------------------------------------------------*/ /* --- @p_txstart@ --- * @@ -1132,6 +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 @@ -1185,7 +1312,7 @@ extern void p_destroy(peer */*p*/); #define FOREACH_PEER(p, stuff) do { \ peer_iter i_; \ peer *p; \ - for (p_mkiter(&i_); (p = p_next(&i_)) != 0; ) do stuff while (0); \ + for (p_mkiter(&i_); (p = p_next(&i_)) != 0; ) stuff \ } while (0) /* --- @p_mkiter@ --- * @@ -1235,7 +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*/); @@ -1248,7 +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*/); @@ -1260,7 +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*/);