Linux Certif

Toute la documentation sur la certification Linux LPI

crypt

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#define _XOPEN_SOURCE
#include <unistd.h>

char *crypt(const char *key, const char *salt);

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key ¤Ï¥æ¡¼¥¶¤¬ÆþÎϤ¹¤ë¥Ñ¥¹¥ï¡¼¥É¤Ç¤¢¤ë¡£

salt ¤Ï½¸¹ç [a-zA-Z0-9./] ¤«¤éÁª¤Ð¤ì¤¿ 2 ʸ»ú¤Îʸ»úÎó¤Ç¤¢¤ë¡£ ¤³¤Îʸ»úÎó¤Ï¥¢¥ë¥´¥ê¥º¥à¤Î½ÐÎϤò 4096 Ä̤ê¤Ë¤«¤­Í𤹤Τ˻Ȥï¤ì¤ë¡£

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·Ù¹ð: ¸°¶õ´Ö¤Ï 2**56 = 7.2e16 ¤Î²Äǽ¤ÊÃͤ«¤éÀ®¤ë¡£ ¤³¤Î¸°¶õ´Ö¤ÎÁ´Ãµº÷¤Ï¶¯ÎϤÊÊÂÎó·×»»µ¡¤ò»È¤¨¤Ð²Äǽ¤Ç¤¢¤ë¡£¤Þ¤¿ crack(1) ¤Î¤è¤¦¤Ê¥½¥Õ¥È¥¦¥§¥¢¤Ï¤³¤Î¸°¶õ´Ö¤ÎÃæ¤Ç¡¢Â¿¤¯¤Î¿Í¤Ë¥Ñ¥¹¥ï¡¼¥É¤È¤·¤Æ »È¤ï¤ì¤ë¤è¤¦¤Ê¸°¤Ë¤Ä¤¤¤Æ¤ÎÁ´Ãµº÷¤¬²Äǽ¤Ç¤¢¤ë¡£ ¤½¤ì¤æ¤¨¡¢¥Ñ¥¹¥ï¡¼¥É¤òÁªÂò¤¹¤ë¤È¤­¤Ë¤Ï¡¢¤¹¤¯¤Ê¤¯¤È¤â¡¢ °ìÈÌŪ¤Ë»È¤ï¤ì¤ëñ¸ì¤È̾Á°¤ÏÈò¤±¤ë¤Ù¤­¤Ç¤¢¤ë¡£ passwd(1) ¤ò»È¤¦»þ¤Ë¤Ï¥¯¥é¥Ã¥¯¤µ¤ì¤¦¤ë¥Ñ¥¹¥ï¡¼¥É¤Ë¤Ä¤¤¤Æ¤Î¸¡ºº¤ò¤¹¤ë¤³¤È¤¬ ¿ä¾©¤µ¤ì¤ë¡£

DES ¥¢¥ë¥´¥ê¥º¥à¤Ë¤Ï¤¤¤¯¤Ä¤«¤ÎÊʤ¬¤¢¤ê¡¢¤½¤ì¤Ë¤è¤Ã¤Æ¥Ñ¥¹¥ï¡¼¥Éǧ¾Ú°Ê³°¤Ë crypt(3) ¤ò»È¤¦¤Î¤Ï¤¿¤¤¤Ø¤ó¤è¤¯¤Ê¤¤ÁªÂò¤È¤Ê¤Ã¤Æ¤¤¤ë¡£¤â¤· crypt(3) ¤ò°Å¹æ¥×¥í¥¸¥§¥¯¥È¤Ë»È¤ª¤¦¤È¤¤¤¦°Æ¤ò¤â¤Ã¤Æ¤¤¤ë¤Ê¤é¤Ð¡¢¤½¤ì¤Ï¤ä¤á¤¿¤Û¤¦¤¬ ¤è¤¤¡£°Å¹æ²½¤Ë¤Ä¤¤¤Æ¤Î¤è¤¤ËܤÈï¤Ç¤âÆþ¼ê¤Ç¤­¤ë DES ¥é¥¤¥Ö¥é¥ê¤Î¤Ò¤È¤Ä¤ò ¼ê¤Ë¤¤¤ì¤ë¤Ù¤­¤À¡£

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ENOSYS

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SVr4, 4.3BSD, POSIX.1-2001

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glibc ¤Ç¤ÎÃí°Õ

¤³¤Î´Ø¿ô¤Î glibc2 ÈǤϰʲ¼¤Î¤è¤¦¤Ê³ÈÄ¥µ¡Ç½¤¬¤¢¤ë¡£ ¤â¤· salt ¤Îʸ»úÎó¤ÎºÇ½é¤Î 3 ʸ»ú¤¬ "$1$" ¤Ç¤¢¤ê¡¢ºÇÂç 8 ʸ»ú¤Î¸å¡¢ ºÇ¸å¤Ë "$" ¤Ç½ª¤ï¤Ã¤Æ¤¤¤ë(¤³¤ì¤Ï¤Ê¤¯¤Æ¤â¤è¤¤)¾ì¹ç¡¢ DES ¤Ç¤Ï¤Ê¤¯ MD5 ¤ò»È¤Ã¤¿°Å¹æ²½¥¢¥ë¥´¥ê¥º¥à¤¬ÍѤ¤¤é¤ì¡¢ ½ÐÎϤϺÇÂç 34 ¥Ð¥¤¥È¤È¤Ê¤ë¡£ ½ÐÎÏ¤Ï "$1$<salt>$<encoded>" ¤Î·Á¼°¤Ç¤¢¤ê¡¢ "<salt>" ¤Ï salt ¤Ë¤ª¤±¤ë "$1$" ¤Ë°ú¤­Â³¤¯ 8 ʸ»ú°Ê²¼¤Îʸ»úÎó¡¢ "<encoded>" ¤Ï°ú¤­Â³¤¯ 22 ʸ»ú¤Îʸ»úÎó¤Ç¤¢¤ë¡£ "<salt>" ¤È "<encoded>" ¤Îʸ»ú¤Ï [a-zA-Z0-9./] ¤Î½¸¹ç¤«¤é Áª¤Ð¤ì¤ë¡£ ¤³¤Î¾ì¹ç¡¢(ºÇ½é¤Î 8 ʸ»ú¤Ç¤Ï¤Ê¤¯) ¥­¡¼ Á´ÂΤ¬°ÕÌ£¤¬¤¢¤ë¡£

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login(1), passwd(1), encrypt(3), getpass(3), passwd(5), feature_test_macros(7)