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comparison lib/password.c @ 1090:7c62d5db4484 draft

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Minor lib/password.c cleanup, described on the list. (Inline two functions.)
author Rob Landley <rob@landley.net>
date Wed, 16 Oct 2013 20:01:46 -0500
parents 77235d224b1d
children bbed38cf7236
comparison
equal deleted inserted replaced
1089:77235d224b1d 1090:7c62d5db4484
5 5
6 #include "toys.h" 6 #include "toys.h"
7 #include "xregcomp.h" 7 #include "xregcomp.h"
8 #include <time.h> 8 #include <time.h>
9 9
10 static unsigned int random_number_generator(int fd)
11 {
12 unsigned int randnum;
13
14 xreadall(fd, &randnum, sizeof(randnum));
15 return randnum;
16 }
17
18 static char inttoc(int i)
19 {
20 // salt value uses 64 chracters in "./0-9a-zA-Z"
21 const char character_set[]="./0123456789abcdefghijklmnopqrstuvwxyz"
22 "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
23
24 i &= 0x3f; // masking for using 10 bits only
25 return character_set[i];
26 }
27
28 int get_salt(char *salt, char *algo) 10 int get_salt(char *salt, char *algo)
29 { 11 {
30 int i, randfd, salt_length = 0, offset; 12 int i, len = 0, offset = 0;
31 13 char buf[12];
32 if (!strcmp(algo,"des")){ 14
33 // 2 bytes salt value is used in des 15 if (!strcmp(algo,"des")) len = 2;
34 salt_length = 2; 16 else {
35 offset = 0;
36 } else {
37 *salt++ = '$'; 17 *salt++ = '$';
38 if (!strcmp(algo,"md5")){ 18 if (!strcmp(algo,"md5")) {
39 *salt++ = '1'; 19 *salt++ = '1';
40 // 8 bytes salt value is used in md5 20 len = 8;
41 salt_length = 8; 21 } else if (!strcmp(algo,"sha256")) {
42 } else if (!strcmp(algo,"sha256")){
43 *salt++ = '5'; 22 *salt++ = '5';
44 // 16 bytes salt value is used in sha256 23 len = 16;
45 salt_length = 16; 24 } else if (!strcmp(algo,"sha512")) {
46 } else if (!strcmp(algo,"sha512")){
47 *salt++ = '6'; 25 *salt++ = '6';
48 // 16 bytes salt value is used in sha512 26 len = 16;
49 salt_length = 16;
50 } else return -1; 27 } else return -1;
51 28
52 *salt++ = '$'; 29 *salt++ = '$';
53 offset = 3; 30 offset = 3;
54 } 31 }
55 32
56 randfd = xopen("/dev/urandom", O_RDONLY); 33 // Read appropriate number of random bytes for salt
57 for (i=0; i<salt_length; i++) 34 i = xopen("/dev/urandom", O_RDONLY);
58 salt[i] = inttoc(random_number_generator(randfd)); 35 xreadall(i, buf, ((len*6)+7)/8);
59 salt[salt_length+1] = '\0'; 36 close(i);
60 xclose(randfd); 37
38 // Grab 6 bit chunks and convert to characters in ./0-9a-zA-Z
39 for (i=0; i<len; i++) {
40 int bitpos = i*6, bits = bitpos/8;
41
42 bits = ((buf[i]+(buf[i+1]<<8)) >> (bitpos&7)) & 0x3f;
43 bits += 46;
44 if (bits > 57) bits += 8;
45 if (bits > 90) bits += 7;
46
47 salt[i] = bits;
48 }
49 salt[i] = 0;
61 50
62 return offset; 51 return offset;
63 } 52 }
64 53
65 static void handle(int signo) 54 static void handle(int signo)