X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?a=blobdiff_plain;f=util.h;h=1086ad8d2daf6a6dd4d2a0f6953b87cfb987d8fc;hb=4bc0381500403be5f3e40bc39f65a2d8fb75cf19;hp=d4663dbf6c98a65de699c23312e926c8d42e335c;hpb=5f37eb107bd4370ee0ed1c1c185abb06ee873ac2;p=secnet.git

diff --git a/util.h b/util.h
index d4663db..1086ad8 100644
--- a/util.h
+++ b/util.h
@@ -1,3 +1,22 @@
+/*
+ * This file is part of secnet.
+ * See README for full list of copyright holders.
+ *
+ * secnet 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * secnet 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
+ * version 3 along with secnet; if not, see
+ * https://www.gnu.org/licenses/gpl.html.
+ */
+
 #ifndef util_h
 #define util_h
 
@@ -30,6 +49,41 @@ extern void *buf_prepend(struct buffer_if *buf, int32_t amount);
 extern void *buf_unappend(struct buffer_if *buf, int32_t amount);
 extern void *buf_unprepend(struct buffer_if *buf, int32_t amount);
 
+/* These construct a message in a buffer, truncating if necessary.
+ * _string is only safe for trusted input and *not* UTF-8 (sorry).
+ * _packet_string is safe for any input, including untrusted.
+ * _terminate arranges for the buffer to be null-terminated (and
+ * maybe for a trailing `...' to indicate truncation), and returns
+ * a pointer to the null-terminated string. */
+void truncmsg_add_string(struct buffer_if *buf, cstring_t s);
+void truncmsg_add_packet_string(struct buffer_if*, int32_t, const uint8_t*);
+const char *truncmsg_terminate(const struct buffer_if *buf);
+
+
+struct priomsg {
+    /* U: uninitialised
+     * F: initialised but free (no memory allocated), no leak if discarded
+     * Z: contains no message yet
+     * M: contains some message; you may call truncmsg_add_*
+     */
+    int prio;
+    struct buffer_if m;
+};
+
+void priomsg_new(struct priomsg *pm, int32_t maxlen);          /* UF -> Z */
+void priomsg_destroy(struct priomsg *pm, int32_t maxlen);     /* FZM -> F */
+void priomsg_reset(struct priomsg *pm);                       /* FZM -> Z */
+bool_t priomsg_update_p(struct priomsg *pm, int prio);         /* ZM -> M */
+  /* returns true iff message of priority prio ought to be added,
+   * caller should then call truncmsg_add_*.
+   * pm may be NULL, in which case it just returns false */
+const char *priomsg_getmessage(const struct priomsg *pm, const char *defmsg);
+  /* return value is null-terminated, valid until next call
+   * or until defmsg is no longer valid                                ZM */
+
+bool_t priomsg_update_fixed(struct priomsg *pm, int prio, const char *m);
+  /* convenience combination of _update_p and truncmsg_add_string */
+
 /*
  * void BUF_ADD_BYTES(append,    struct buffer_if*, const void*, int32_t size);
  * void BUF_ADD_BYTES(prepend,   struct buffer_if*, const void*, int32_t size);
@@ -67,12 +121,35 @@ extern void buffer_readonly_clone(struct buffer_if *n, const struct buffer_if*);
    * it must NOT be freed. */
 
 extern void buf_append_string(struct buffer_if *buf, cstring_t s);
+  /* Append a two-byte length and the string to the buffer. Length is in
+   * network byte order. */
+
+static inline int hex_encode_size(int binsize) { return binsize*2 + 1; }
+extern void hex_encode(const uint8_t *bin, int binsize, char *buf);
+  /* Convert a byte array to hex into a supplied buffer. */
+extern string_t hex_encode_alloc(const uint8_t *bin, int binsize);
+  /* Returns the result in a freshly allocated string. */
+
+extern bool_t hex_decode(uint8_t *buffer, int32_t buflen, int32_t *outlen,
+			 cstring_t hb, bool_t allow_odd_nibble);
+  /* Convert a hex string to binary, storing the result in buffer.  If
+   * allow_odd_nibble then it is acceptable if the input is an odd number of
+   * digits, and an additional leading zero digit is assumed; otherwise, this
+   * is not acceptable and the conversion fails.
+   *
+   * The input is processed left to right until it is consumed, the buffer is
+   * full, or an error is encountered in the input.  The length of output
+   * produced is stored in *outlen.  Returns true if the entire input was
+   * processed without error; otherwise false. */
 
 extern void read_mpbin(MP_INT *a, uint8_t *bin, int binsize);
+  /* Convert a buffer into its MP_INT representation */
 
 extern char *write_mpstring(MP_INT *a);
+  /* Convert a MP_INT into a hex string */
 
 extern int32_t write_mpbin(MP_INT *a, uint8_t *buffer, int32_t buflen);
+  /* Convert a MP_INT into a buffer; return length; truncate if necessary */
 
 extern struct log_if *init_log(list_t *loglist);
 
@@ -82,6 +159,9 @@ extern void send_nak(const struct comm_addr *dest, uint32_t our_index,
 
 extern int consttime_memeq(const void *s1, const void *s2, size_t n);
 
+void hash_hash(const struct hash_if *hashi, const void *msg, int32_t len,
+	       uint8_t *digest /* hi->hlen bytes */);
+
 const char *iaddr_to_string(const union iaddr *ia);
 int iaddr_socklen(const union iaddr *ia);
 
@@ -89,7 +169,34 @@ void string_item_to_iaddr(const item_t *item, uint16_t port, union iaddr *ia,
 			  const char *desc);
 
 
-#define SBUF (bufs[b]) /* temporary macro */
+/*----- pathprefix_template -----*/
+
+struct pathprefix_template {
+    char *buffer;
+    char *write_here;
+};
+
+void pathprefix_template_init(struct pathprefix_template *out,
+			      const char *prefix, int maxsuffix);
+static inline void pathprefix_template_setsuffix
+   (struct pathprefix_template *upd, const char *suffix)
+   { strcpy(upd->write_here,suffix); }
+
+
+/*
+ * SBUF_DEFINE(int nbufs, size_t size);
+ *   // Generates a number of definitions and statements organising
+ *   // nbufs rotating char[size] buffers such that subsequent code
+ *   // may refer to:
+ * char *const SBUF;
+ */
+#define SBUF_DEFINE(nbufs, size)			\
+    static int static_bufs__bufnum;			\
+    static char static_bufs__bufs[(nbufs)][(size)];	\
+    static_bufs__bufnum++;				\
+    static_bufs__bufnum %= (nbufs);			\
+    static_bufs__bufs[static_bufs__bufnum]
+#define SBUF (static_bufs__bufs[static_bufs__bufnum])
 
 /*----- line-buffered asynch input -----*/