API tools faq
paste
Advertisement
teknoraver

sha1sum af_alg

teknoraver
Feb 28th, 2018
234
0
Never
Add comment
Not a member of Pastebin yet? Sign Up, it unlocks many cool features!
Diff 6.47 KB | None | 0 0
raw download clone embed print report
  1. From 14a87657afc7494ceef26e06acb514e7097e3a20 Mon Sep 17 00:00:00 2001
  2. From: Matteo Croce <mcroce@redhat.com>
  3. Date: Sun, 22 Apr 2018 12:24:30 +0200
  4. Subject: [PATCH] sha1sum: use AF_ALG when available
  5.  
  6. Linux supports accessing kernel cryptographic API via AF_ALG since
  7. version 2.6.38. Coreutils uses libcrypto when available and fallbacks to
  8. generic C implementation of various hashing functions.
  9. Add a generic afalg_stream() function which uses AF_ALG to calculate the
  10. hash of a stream and use sendfile() when possible (regular file with size
  11. less or equal than 0x7ffff000 (2,147,479,552) bytes, AKA MAX_RW_COUNT).
  12. USe afalg_stream() only in sha1sum for now, but other hashes are possible.
  13.  
  14. Signed-off-by: Matteo Croce <mcroce@redhat.com>
  15. ---
  16. lib/af_alg.c        | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++++
  17.  lib/af_alg.h        |  46 ++++++++++++++++++++++++
  18.  lib/sha1.c          |  14 +++++++-
  19.  modules/crypto/sha1 |   5 ++-
  20.  4 files changed, 165 insertions(+), 2 deletions(-)
  21.  create mode 100644 lib/af_alg.c
  22.  create mode 100644 lib/af_alg.h
  23.  
  24. diff --git a/lib/af_alg.c b/lib/af_alg.c
  25. new file mode 100644
  26. index 000000000..0a1437d6c
  27. --- /dev/null
  28. +++ b/lib/af_alg.c
  29. @@ -0,0 +1,102 @@
  30. +/* AF_ALG support
  31. +
  32. +   This program is free software; you can redistribute it and/or modify it
  33. +   under the terms of the GNU General Public License as published by the
  34. +   Free Software Foundation; either version 2, or (at your option) any
  35. +   later version.
  36. +
  37. +   This program is distributed in the hope that it will be useful,
  38. +   but WITHOUT ANY WARRANTY; without even the implied warranty of
  39. +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  40. +   GNU General Public License for more details.
  41. +
  42. +   You should have received a copy of the GNU General Public License
  43. +   along with this program; if not, see <https://www.gnu.org/licenses/>.  */
  44. +
  45. +#include <config.h>
  46. +
  47. +#include "af_alg.h"
  48. +
  49. +/* from linux/include/linux/fs.h: (INT_MAX & PAGE_MASK) */
  50. +#define MAX_RW_COUNT 0x7FFFF000
  51. +#define BLOCKSIZE 32768
  52. +
  53. +int
  54. +afalg_stream (FILE * stream, void *resblock, const char *alg, int hashlen)
  55. +{
  56. +  struct sockaddr_alg salg = {
  57. +    .salg_family = AF_ALG,
  58. +    .salg_type = "hash",
  59. +  };
  60. +  int ret, cfd, ofd;
  61. +  static char buf[BLOCKSIZE];
  62. +  ssize_t size;
  63. +  struct stat st;
  64. +
  65. +  strcpy((char *)salg.salg_name, alg);
  66. +  cfd = socket (AF_ALG, SOCK_SEQPACKET, 0);
  67. +  if (cfd < 0)
  68. +      return -EAFNOSUPPORT;
  69. +
  70. +  ret = bind (cfd, (struct sockaddr *) &salg, sizeof (salg));
  71. +  if (ret < 0)
  72. +    {
  73. +      ret = -EAFNOSUPPORT;
  74. +      goto out_cfd;
  75. +    }
  76. +
  77. +  ofd = accept (cfd, NULL, 0);
  78. +  if (ofd < 0)
  79. +    {
  80. +      ret = -EAFNOSUPPORT;
  81. +      goto out_ofd;
  82. +    }
  83. +
  84. +  /* if file is a regular file, attempt sendfile() to pipe the data */
  85. +  if (!fstat(fileno(stream), &st) && S_ISREG(st.st_mode) &&
  86. +      st.st_size <= MAX_RW_COUNT)
  87. +    {
  88. +      if (sendfile(ofd, fileno(stream), NULL, st.st_size) == -1)
  89. +        ret = -EIO;
  90. +      else
  91. +        ret = 0;
  92. +    } else {
  93. +      /* sendfile() not possible, do a classic read-write loop */
  94. +      while ((size = fread (buf, 1, sizeof (buf), stream)))
  95. +        {
  96. +          if (send (ofd, buf, size, size == sizeof (buf) ? MSG_MORE : 0) == -1)
  97. +            {
  98. +              ret = -EIO;
  99. +              goto out_ofd;
  100. +            }
  101. +        }
  102. +  }
  103. +
  104. +  size = read (ofd, resblock, hashlen);
  105. +  if (size != hashlen)
  106. +    {
  107. +      fprintf (stderr, "Error from read (%zd vs %d bytes): %s\n",
  108. +               size, hashlen, strerror (errno));
  109. +      ret = -EIO;
  110. +    }
  111. +  else
  112. +    {
  113. +      ret = 0;
  114. +    }
  115. +out_ofd:
  116. +  close (ofd);
  117. +out_cfd:
  118. +  close (cfd);
  119. +  return ret;
  120. +}
  121. +
  122. +# ifdef __cplusplus
  123. +}
  124. +# endif
  125. +
  126. +/*
  127. + * Hey Emacs!
  128. + * Local Variables:
  129. + * coding: utf-8
  130. + * End:
  131. + */
  132. diff --git a/lib/af_alg.h b/lib/af_alg.h
  133. new file mode 100644
  134. index 000000000..678c03aad
  135. --- /dev/null
  136. +++ b/lib/af_alg.h
  137. @@ -0,0 +1,46 @@
  138. +/* AF_ALG support
  139. +
  140. +   This program is free software; you can redistribute it and/or modify it
  141. +   under the terms of the GNU General Public License as published by the
  142. +   Free Software Foundation; either version 2, or (at your option) any
  143. +   later version.
  144. +
  145. +   This program is distributed in the hope that it will be useful,
  146. +   but WITHOUT ANY WARRANTY; without even the implied warranty of
  147. +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  148. +   GNU General Public License for more details.
  149. +
  150. +   You should have received a copy of the GNU General Public License
  151. +   along with this program; if not, see <https://www.gnu.org/licenses/>.  */
  152. +
  153. +#ifndef AF_ALG_H
  154. +# define AF_ALG_H 1
  155. +
  156. +# include <unistd.h>
  157. +# include <stdio.h>
  158. +# include <string.h>
  159. +# include <errno.h>
  160. +# include <linux/if_alg.h>
  161. +# include <sys/socket.h>
  162. +# include <sys/stat.h>
  163. +# include <sys/sendfile.h>
  164. +
  165. +# ifdef __cplusplus
  166. +extern "C" {
  167. +# endif
  168. +
  169. +int
  170. +afalg_stream (FILE * stream, void *resblock, const char *alg, int hashlen);
  171. +
  172. +# ifdef __cplusplus
  173. +}
  174. +# endif
  175. +
  176. +#endif
  177. +
  178. +/*
  179. + * Hey Emacs!
  180. + * Local Variables:
  181. + * coding: utf-8
  182. + * End:
  183. + */
  184. diff --git a/lib/sha1.c b/lib/sha1.c
  185. index 37d46b68e..db85e6ffd 100644
  186. --- a/lib/sha1.c
  187. +++ b/lib/sha1.c
  188. @@ -23,6 +23,8 @@
  189.  
  190.  #include <config.h>
  191.  
  192. +#include "af_alg.h"
  193. +
  194.  #if HAVE_OPENSSL_SHA1
  195.  # define GL_OPENSSL_INLINE _GL_EXTERN_INLINE
  196.  #endif
  197. @@ -122,6 +124,7 @@ sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf)
  198.  }
  199.  #endif
  200.  
  201. +
  202.  /* Compute SHA1 message digest for bytes read from STREAM.  The
  203.     resulting message digest number will be written into the 16 bytes
  204.     beginning at RESBLOCK.  */
  205. @@ -130,8 +133,17 @@ sha1_stream (FILE *stream, void *resblock)
  206.  {
  207.    struct sha1_ctx ctx;
  208.    size_t sum;
  209. +  int ret;
  210. +  char *buffer;
  211. +
  212. +  ret = afalg_stream(stream, resblock, "sha1", SHA1_DIGEST_SIZE);
  213. +  if (!ret)
  214. +      return 0;
  215. +
  216. +  if (ret == -EIO)
  217. +      return 1;
  218.  
  219. -  char *buffer = malloc (BLOCKSIZE + 72);
  220. +  buffer = malloc (BLOCKSIZE + 72);
  221.    if (!buffer)
  222.      return 1;
  223.  
  224. diff --git a/modules/crypto/sha1 b/modules/crypto/sha1
  225. index d65f99418..a2b7df211 100644
  226. --- a/modules/crypto/sha1
  227. +++ b/modules/crypto/sha1
  228. @@ -5,6 +5,8 @@ Files:
  229.  lib/gl_openssl.h
  230.  lib/sha1.h
  231.  lib/sha1.c
  232. +lib/af_alg.h
  233. +lib/af_alg.c
  234.  m4/gl-openssl.m4
  235.  m4/sha1.m4
  236.  
  237. @@ -17,10 +19,11 @@ configure.ac:
  238.  gl_SHA1
  239.  
  240.  Makefile.am:
  241. -lib_SOURCES += sha1.c
  242. +lib_SOURCES += sha1.c af_alg.c
  243.  
  244.  Include:
  245.  "sha1.h"
  246. +"af_alg.h"
  247.  
  248.  Link:
  249.  $(LIB_CRYPTO)
  250. --
  251. 2.14.3
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement
Public Pastes
Advertisement
We use cookies for various purposes including analytics. By continuing to use Pastebin, you agree to our use of cookies as described in the Cookies Policy.  OK, I Understand
Not a member of Pastebin yet?
Sign Up, it unlocks many cool features!