contrib/ntpd/imsg.c

   1 /*      $OpenBSD: src/usr.sbin/ntpd/imsg.c,v 1.10 2005/03/23 10:42:04 henning Exp $ */
   2
   3 /*
   4  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
  15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <sys/types.h>
  20
  21 #include <errno.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <unistd.h>
  25
  26 #include "ntpd.h"
  27
  28 void
  29 imsg_init(struct imsgbuf *ibuf, int fd)
  30 {
  31         msgbuf_init(&ibuf->w);
  32         bzero(&ibuf->r, sizeof(ibuf->r));
  33         ibuf->fd = fd;
  34         ibuf->w.fd = fd;
  35         ibuf->pid = getpid();
  36 }
  37
  38 int
  39 imsg_read(struct imsgbuf *ibuf)
  40 {
  41         ssize_t                  n;
  42
  43         if ((n = read(ibuf->fd, ibuf->r.buf + ibuf->r.wpos,
  44             sizeof(ibuf->r.buf) - ibuf->r.wpos)) == -1) {
  45                 if (errno != EINTR && errno != EAGAIN) {
  46                         log_warn("imsg_read: pipe read error");
  47                         return (-1);
  48                 }
  49                 return (0);
  50         }
  51
  52         ibuf->r.wpos += n;
  53
  54         return (n);
  55 }
  56
  57 int
  58 imsg_get(struct imsgbuf *ibuf, struct imsg *imsg)
  59 {
  60         size_t                   av, left, datalen;
  61
  62         av = ibuf->r.wpos;
  63
  64         if (IMSG_HEADER_SIZE > av)
  65                 return (0);
  66
  67         memcpy(&imsg->hdr, ibuf->r.buf, sizeof(imsg->hdr));
  68         if (imsg->hdr.len < IMSG_HEADER_SIZE ||
  69             imsg->hdr.len > MAX_IMSGSIZE) {
  70                 log_warnx("imsg_get: imsg hdr len out of bounds");
  71                 return (-1);
  72         }
  73         if (imsg->hdr.len > av)
  74                 return (0);
  75         datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
  76         ibuf->r.rptr = ibuf->r.buf + IMSG_HEADER_SIZE;
  77         if ((imsg->data = malloc(datalen)) == NULL) {
  78                 log_warn("imsg_get");
  79                 return (-1);
  80         }
  81         memcpy(imsg->data, ibuf->r.rptr, datalen);
  82
  83         if (imsg->hdr.len < av) {
  84                 left = av - imsg->hdr.len;
  85                 memmove(&ibuf->r.buf, ibuf->r.buf + imsg->hdr.len, left);
  86                 ibuf->r.wpos = left;
  87         } else
  88                 ibuf->r.wpos = 0;
  89
  90         return (datalen + IMSG_HEADER_SIZE);
  91 }
  92
  93 int
  94 imsg_compose(struct imsgbuf *ibuf, enum imsg_type type, u_int32_t peerid,
  95     pid_t pid, void *data, u_int16_t datalen)
  96 {
  97         struct buf      *wbuf;
  98         int              n;
  99
 100         if ((wbuf = imsg_create(ibuf, type, peerid, pid, datalen)) == NULL)
 101                 return (-1);
 102
 103         if (imsg_add(wbuf, data, datalen) == -1)
 104                 return (-1);
 105
 106         if ((n = imsg_close(ibuf, wbuf)) < 0)
 107                 return (-1);
 108
 109         return (n);
 110 }
 111
 112 struct buf *
 113 imsg_create(struct imsgbuf *ibuf, enum imsg_type type, u_int32_t peerid,
 114     pid_t pid, u_int16_t datalen)
 115 {
 116         struct buf      *wbuf;
 117         struct imsg_hdr  hdr;
 118
 119         if (datalen > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
 120                 log_warnx("imsg_create: len %u > MAX_IMSGSIZE; "
 121                     "type %u peerid %lu", datalen + IMSG_HEADER_SIZE,
 122                     type, peerid);
 123                 return (NULL);
 124         }
 125
 126         hdr.len = datalen + IMSG_HEADER_SIZE;
 127         hdr.type = type;
 128         hdr.peerid = peerid;
 129         hdr.pid = pid;
 130         if ((wbuf = buf_open(hdr.len)) == NULL) {
 131                 log_warn("imsg_create: buf_open");
 132                 return (NULL);
 133         }
 134         if (imsg_add(wbuf, &hdr, sizeof(hdr)) == -1)
 135                 return (NULL);
 136
 137         return (wbuf);
 138 }
 139
 140 int
 141 imsg_add(struct buf *msg, void *data, u_int16_t datalen)
 142 {
 143         if (datalen)
 144                 if (buf_add(msg, data, datalen) == -1) {
 145                         log_warnx("imsg_add: buf_add error");
 146                         buf_free(msg);
 147                         return (-1);
 148                 }
 149         return (datalen);
 150 }
 151
 152 int
 153 imsg_close(struct imsgbuf *ibuf, struct buf *msg)
 154 {
 155         int     n;
 156
 157         if ((n = buf_close(&ibuf->w, msg)) < 0) {
 158                         log_warnx("imsg_close: buf_close error");
 159                         buf_free(msg);
 160                         return (-1);
 161         }
 162         return (n);
 163 }
 164
 165 void
 166 imsg_free(struct imsg *imsg)
 167 {
 168         free(imsg->data);
 169 }