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+/*
+ * ----------------------------------------------------------------------------
+ * "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
+ * ----------------------------------------------------------------------------
+ */
+
+/*
+ * Ported from FreeBSD to Linux, only minimal changes. --marekm
+ */
+
+/*
+ * Adapted from shadow-19990607 by Tudor Bosman, tudorb@jm.nu
+ */
+
+#include "config.h"
+
+#ifdef HAVE_MD5_PASSWORDS
+
+#include <unistd.h>
+#include <string.h>
+
+#ifdef HAVE_OPENSSL
+#include <openssl/md5.h>
+#endif
+
+#ifdef HAVE_SSL
+#include <ssl/md5.h>
+#endif
+
+static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */
+ "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+
+static char *magic = "$1$"; /*
+ * This string is magic for
+ * this algorithm. Having
+ * it this way, we can get
+ * get better later on
+ */
+
+static void
+to64(char *s, unsigned long v, int n)
+{
+ while (--n >= 0) {
+ *s++ = itoa64[v&0x3f];
+ v >>= 6;
+ }
+}
+
+int
+is_md5_salt(const char *salt)
+{
+ return (!strncmp(salt, magic, strlen(magic)));
+}
+
+/*
+ * UNIX password
+ *
+ * Use MD5 for what it is best at...
+ */
+
+char *
+md5_crypt(const char *pw, const char *salt)
+{
+ 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;
+
+ MD5_Init(&ctx);
+
+ /* The password first, since that is what is most unknown */
+ MD5_Update(&ctx,pw,strlen(pw));
+
+ /* Then our magic string */
+ MD5_Update(&ctx,magic,strlen(magic));
+
+ /* Then the raw salt */
+ MD5_Update(&ctx,sp,sl);
+
+ /* Then just as many characters of the MD5(pw,salt,pw) */
+ MD5_Init(&ctx1);
+ MD5_Update(&ctx1,pw,strlen(pw));
+ MD5_Update(&ctx1,sp,sl);
+ MD5_Update(&ctx1,pw,strlen(pw));
+ MD5_Final(final,&ctx1);
+ for(pl = strlen(pw); pl > 0; pl -= 16)
+ MD5_Update(&ctx,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)
+ MD5_Update(&ctx, final+j, 1);
+ else
+ MD5_Update(&ctx, pw+j, 1);
+
+ /* Now make the output string */
+ strcpy(passwd,magic);
+ strncat(passwd,sp,sl);
+ strcat(passwd,"$");
+
+ MD5_Final(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++) {
+ MD5_Init(&ctx1);
+ if(i & 1)
+ MD5_Update(&ctx1,pw,strlen(pw));
+ else
+ MD5_Update(&ctx1,final,16);
+
+ if(i % 3)
+ MD5_Update(&ctx1,sp,sl);
+
+ if(i % 7)
+ MD5_Update(&ctx1,pw,strlen(pw));
+
+ if(i & 1)
+ MD5_Update(&ctx1,final,16);
+ else
+ MD5_Update(&ctx1,pw,strlen(pw));
+ MD5_Final(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;
+}
+
+#endif /* HAVE_MD5_PASSWORDS */