lib/libc/hash/hashhl.c

   1 /* $NetBSD: hashhl.c,v 1.7 2014/09/24 13:18:52 christos Exp $ */
   2
   3 /*
   4  * ----------------------------------------------------------------------------
   5  * "THE BEER-WARE LICENSE" (Revision 42):
   6  * <phk@login.dkuug.dk> wrote this file.  As long as you retain this notice you
   7  * can do whatever you want with this stuff. If we meet some day, and you think
   8  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
   9  * ----------------------------------------------------------------------------
  10  */
  11
  12 /*
  13  * Modified September 24, 2005 by Elad Efrat <elad@NetBSD.org>
  14  * Modified April 29, 1997 by Jason R. Thorpe <thorpej@NetBSD.org>
  15  */
  16
  17 #ifdef HASH_ALGORITHM
  18
  19 #if HAVE_NBTOOL_CONFIG_H
  20 #include "nbtool_config.h"
  21 #endif
  22
  23 /*
  24  * Do all the name mangling before we include "namespace.h"
  25  */
  26 #define CONCAT(x,y)     __CONCAT(x,y)
  27
  28 #ifndef HASH_FNPREFIX
  29 #define HASH_FNPREFIX   HASH_ALGORITHM
  30 #endif /* !HASH_FNPREFIX */
  31
  32 #define FNPREFIX(x)     CONCAT(HASH_FNPREFIX,x)
  33 #define HASH_CTX        CONCAT(HASH_ALGORITHM,_CTX)
  34 #define HASH_LEN        CONCAT(HASH_ALGORITHM,_DIGEST_LENGTH)
  35 #define HASH_STRLEN     CONCAT(HASH_ALGORITHM,_DIGEST_STRING_LENGTH)
  36
  37 #if !defined(_KERNEL) && defined(__weak_alias) && !defined(HAVE_NBTOOL_CONFIG_H)
  38 #define WA(a,b) __weak_alias(a,b)
  39 WA(FNPREFIX(End),CONCAT(_,FNPREFIX(End)))
  40 WA(FNPREFIX(FileChunk),CONCAT(_,FNPREFIX(FileChunk)))
  41 WA(FNPREFIX(File),CONCAT(_,FNPREFIX(File)))
  42 WA(FNPREFIX(Data),CONCAT(_,FNPREFIX(Data)))
  43 #undef WA
  44 #endif
  45
  46 #include "namespace.h"
  47 #include HASH_INCLUDE
  48
  49 #include <sys/types.h>
  50 #include <sys/stat.h>
  51
  52 #include <assert.h>
  53 #include <fcntl.h>
  54 #include <errno.h>
  55 #include <stdio.h>
  56 #include <stdlib.h>
  57 #include <unistd.h>
  58
  59 #ifndef MIN
  60 #define MIN(x,y)        ((x)<(y)?(x):(y))
  61 #endif /* !MIN */
  62
  63 char *
  64 FNPREFIX(End)(HASH_CTX *ctx, char *buf)
  65 {
  66         int i;
  67         unsigned char digest[HASH_LEN];
  68         static const char hex[]="0123456789abcdef";
  69
  70         _DIAGASSERT(ctx != 0);
  71
  72         if (buf == NULL)
  73                 buf = malloc((size_t)HASH_STRLEN);
  74         if (buf == NULL)
  75                 return (NULL);
  76
  77         FNPREFIX(Final)(digest, ctx);
  78
  79         for (i = 0; i < HASH_LEN; i++) {
  80                 buf[i+i] = hex[(u_int32_t)digest[i] >> 4];
  81                 buf[i+i+1] = hex[digest[i] & 0x0f];
  82         }
  83
  84         buf[i+i] = '\0';
  85         return (buf);
  86 }
  87
  88 char *
  89 FNPREFIX(FileChunk)(const char *filename, char *buf, off_t off, off_t len)
  90 {
  91         struct stat sb;
  92         u_char buffer[BUFSIZ];
  93         HASH_CTX ctx;
  94         int fd, save_errno;
  95         ssize_t nr;
  96
  97         FNPREFIX(Init)(&ctx);
  98
  99         if ((fd = open(filename, O_RDONLY | O_CLOEXEC)) < 0)
 100                 return (NULL);
 101         if (len == 0) {
 102                 if (fstat(fd, &sb) == -1) {
 103                         close(fd);
 104                         return (NULL);
 105                 }
 106                 len = sb.st_size;
 107         }
 108         if (off > 0 && lseek(fd, off, SEEK_SET) < 0) {
 109                 close(fd);
 110                 return (NULL);
 111         }
 112
 113         while ((nr = read(fd, buffer, (size_t) MIN((off_t)sizeof(buffer), len)))
 114             > 0) {
 115                 FNPREFIX(Update)(&ctx, buffer, (unsigned int)nr);
 116                 if (len > 0 && (len -= nr) == 0)
 117                         break;
 118         }
 119
 120         save_errno = errno;
 121         close(fd);
 122         errno = save_errno;
 123         return (nr < 0 ? NULL : FNPREFIX(End)(&ctx, buf));
 124 }
 125
 126 char *
 127 FNPREFIX(File)(const char *filename, char *buf)
 128 {
 129         return (FNPREFIX(FileChunk)(filename, buf, (off_t)0, (off_t)0));
 130 }
 131
 132 char *
 133 FNPREFIX(Data)(const unsigned char *data, size_t len, char *buf)
 134 {
 135         HASH_CTX ctx;
 136
 137         _DIAGASSERT(data != 0);
 138
 139         FNPREFIX(Init)(&ctx);
 140         FNPREFIX(Update)(&ctx, data, (unsigned int)len);
 141         return (FNPREFIX(End)(&ctx, buf));
 142 }
 143
 144 #endif /* HASH_ALGORITHM */