Mercurial > gnulib
view lib/af_alg.c @ 39326:c82e97c04ab4
sys-limits.h: new file for crypto and safe I/O
* lib/af_alg.c: Include sys-limits.h.
(MAX_RW_COUNT): Remove. Use replaced by SYS_BUFSIZE_MAX.
(afalg_stream): Also reject negative sizes for sendfile; they
should not happen and the code is a bit cleaner and faster this way.
* lib/safe-read.c: Include sys-limits.h.
(BUGGY_READ_MAXIMUM): Remove. All uses replaced by SYS_BUFSIZE_MAX.
* lib/sys-limits.h: New file, with values and commentary derived
from the old safe-read.c and from GNU Emacs sysdep.c.
* modules/crypto/md5, modules/crypto/sha1, modules/crypto/sha256:
* modules/crypto/sha512, modules/safe-read, modules/safe-write:
Add lib/sys-limits.h to Files section.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Sat, 05 May 2018 10:27:38 -0700 |
parents | e4fc73a73375 |
children | 6c1bfe046ec3 |
line wrap: on
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/* af_alg.c - Functions to compute message digest from file streams using Linux kernel crypto API. Copyright (C) 2018 Free Software Foundation, Inc. This program 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. This program 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 this program; if not, see <https://www.gnu.org/licenses/>. */ /* Written by Matteo Croce <mcroce@redhat.com>, 2018. */ #include <config.h> #ifdef HAVE_LINUX_IF_ALG_H #include <unistd.h> #include <string.h> #include <linux/if_alg.h> #include <sys/stat.h> #include <sys/sendfile.h> #include <sys/socket.h> #include "af_alg.h" #include "sys-limits.h" #define BLOCKSIZE 32768 int afalg_stream (FILE * stream, const char *alg, void *resblock, ssize_t hashlen) { struct sockaddr_alg salg = { .salg_family = AF_ALG, .salg_type = "hash", }; int ret, cfd, ofd; struct stat st; cfd = socket (AF_ALG, SOCK_SEQPACKET, 0); if (cfd < 0) return -EAFNOSUPPORT; /* avoid calling both strcpy and strlen. */ for (int i = 0; (salg.salg_name[i] = alg[i]); i++) if (i == sizeof salg.salg_name - 1) return -EINVAL; ret = bind (cfd, (struct sockaddr *) &salg, sizeof salg); if (ret < 0) { ret = -EAFNOSUPPORT; goto out_cfd; } ofd = accept (cfd, NULL, 0); if (ofd < 0) { ret = -EAFNOSUPPORT; goto out_cfd; } /* if file is a regular file, attempt sendfile to pipe the data. */ if (!fstat (fileno (stream), &st) && (S_ISREG (st.st_mode) || S_TYPEISSHM (&st) || S_TYPEISTMO (&st)) && 0 < st.st_size && st.st_size <= SYS_BUFSIZE_MAX) { if (sendfile (ofd, fileno (stream), NULL, st.st_size) != st.st_size) { ret = -EIO; goto out_ofd; } else ret = 0; } else { /* sendfile not possible, do a classic read-write loop. */ ssize_t size; char buf[BLOCKSIZE]; while ((size = fread (buf, 1, sizeof buf, stream))) { if (send (ofd, buf, size, MSG_MORE) != size) { ret = -EIO; goto out_ofd; } } if (ferror (stream)) { ret = -EIO; goto out_ofd; } } if (read (ofd, resblock, hashlen) != hashlen) ret = -EIO; else ret = 0; out_ofd: close (ofd); out_cfd: close (cfd); return ret; } #endif