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author | Andrew G. Morgan <morgan@kernel.org> | 2000-06-20 22:10:38 +0000 |
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committer | Andrew G. Morgan <morgan@kernel.org> | 2000-06-20 22:10:38 +0000 |
commit | ea488580c42e8918445a945484de3c8a5addc761 (patch) | |
tree | c992f3ba699caafedfadc16af38e6359c3c24698 /modules/pam_pwdb/md5_crypt.c | |
download | pam-ea488580c42e8918445a945484de3c8a5addc761.tar.gz pam-ea488580c42e8918445a945484de3c8a5addc761.tar.bz2 pam-ea488580c42e8918445a945484de3c8a5addc761.zip |
Initial revision
Diffstat (limited to 'modules/pam_pwdb/md5_crypt.c')
-rw-r--r-- | modules/pam_pwdb/md5_crypt.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/modules/pam_pwdb/md5_crypt.c b/modules/pam_pwdb/md5_crypt.c new file mode 100644 index 00000000..1d755a08 --- /dev/null +++ b/modules/pam_pwdb/md5_crypt.c @@ -0,0 +1,153 @@ +/* $Id$ + * + * ---------------------------------------------------------------------------- + * "THE BEER-WARE LICENSE" (Revision 42): + * <phk@login.dknet.dk> wrote this file. As long as you retain this notice you + * can do whatever you want with this stuff. If we meet some day, and you think + * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp + * ---------------------------------------------------------------------------- + * + * Origin: Id: crypt.c,v 1.3 1995/05/30 05:42:22 rgrimes Exp + * + * $Log$ + * Revision 1.1 2000/06/20 22:11:48 agmorgan + * Initial revision + * + * Revision 1.2 1999/07/04 23:22:38 morgan + * Andrey's MD5 (bigendian) work around + cleanup to address problems with + * applications that let an (ab)user kill them off without giving PAM the + * opportunity to end. [Problem report from Tani Hosokawa on bugtraq.] + * + * Revision 1.1.1.1 1998/07/12 05:17:17 morgan + * Linux PAM sources pre-0.66 + * + * Revision 1.1 1996/09/05 06:43:31 morgan + * Initial revision + * + */ + +#include <string.h> +#include "md5.h" + +static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */ + "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; + +static void +to64(char *s, unsigned long v, int n) +{ + while (--n >= 0) { + *s++ = itoa64[v&0x3f]; + v >>= 6; + } +} + +/* + * UNIX password + * + * Use MD5 for what it is best at... + */ + +char * MD5Name(crypt_md5)(const char *pw, const char *salt) +{ + const char *magic = "$1$"; + /* This string is magic for this algorithm. Having + * it this way, we can get get better later on */ + static char passwd[120], *p; + static const char *sp,*ep; + unsigned char final[16]; + int sl,pl,i,j; + MD5_CTX ctx,ctx1; + unsigned long l; + + /* Refine the Salt first */ + sp = salt; + + /* If it starts with the magic string, then skip that */ + if(!strncmp(sp,magic,strlen(magic))) + sp += strlen(magic); + + /* It stops at the first '$', max 8 chars */ + for(ep=sp;*ep && *ep != '$' && ep < (sp+8);ep++) + continue; + + /* get the length of the true salt */ + sl = ep - sp; + + MD5Name(MD5Init)(&ctx); + + /* The password first, since that is what is most unknown */ + MD5Name(MD5Update)(&ctx,(unsigned const char *)pw,strlen(pw)); + + /* Then our magic string */ + MD5Name(MD5Update)(&ctx,(unsigned const char *)magic,strlen(magic)); + + /* Then the raw salt */ + MD5Name(MD5Update)(&ctx,(unsigned const char *)sp,sl); + + /* Then just as many characters of the MD5(pw,salt,pw) */ + MD5Name(MD5Init)(&ctx1); + MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw)); + MD5Name(MD5Update)(&ctx1,(unsigned const char *)sp,sl); + MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw)); + MD5Name(MD5Final)(final,&ctx1); + for(pl = strlen(pw); pl > 0; pl -= 16) + MD5Name(MD5Update)(&ctx,(unsigned const char *)final,pl>16 ? 16 : pl); + + /* Don't leave anything around in vm they could use. */ + memset(final,0,sizeof final); + + /* Then something really weird... */ + for (j=0,i = strlen(pw); i ; i >>= 1) + if(i&1) + MD5Name(MD5Update)(&ctx, (unsigned const char *)final+j, 1); + else + MD5Name(MD5Update)(&ctx, (unsigned const char *)pw+j, 1); + + /* Now make the output string */ + strcpy(passwd,magic); + strncat(passwd,sp,sl); + strcat(passwd,"$"); + + MD5Name(MD5Final)(final,&ctx); + + /* + * and now, just to make sure things don't run too fast + * On a 60 Mhz Pentium this takes 34 msec, so you would + * need 30 seconds to build a 1000 entry dictionary... + */ + for(i=0;i<1000;i++) { + MD5Name(MD5Init)(&ctx1); + if(i & 1) + MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw)); + else + MD5Name(MD5Update)(&ctx1,(unsigned const char *)final,16); + + if(i % 3) + MD5Name(MD5Update)(&ctx1,(unsigned const char *)sp,sl); + + if(i % 7) + MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw)); + + if(i & 1) + MD5Name(MD5Update)(&ctx1,(unsigned const char *)final,16); + else + MD5Name(MD5Update)(&ctx1,(unsigned const char *)pw,strlen(pw)); + MD5Name(MD5Final)(final,&ctx1); + } + + p = passwd + strlen(passwd); + + l = (final[ 0]<<16) | (final[ 6]<<8) | final[12]; to64(p,l,4); p += 4; + l = (final[ 1]<<16) | (final[ 7]<<8) | final[13]; to64(p,l,4); p += 4; + l = (final[ 2]<<16) | (final[ 8]<<8) | final[14]; to64(p,l,4); p += 4; + l = (final[ 3]<<16) | (final[ 9]<<8) | final[15]; to64(p,l,4); p += 4; + l = (final[ 4]<<16) | (final[10]<<8) | final[ 5]; to64(p,l,4); p += 4; + l = final[11] ; to64(p,l,2); p += 2; + *p = '\0'; + + /* Don't leave anything around in vm they could use. */ + memset(final,0,sizeof final); + + return passwd; +} + |