From 6e1fed7057ee26f21b0e59a5aeb292d4f3f0e8ae Mon Sep 17 00:00:00 2001 From: Wilmer van der Gaast Date: Sun, 25 Jun 2006 19:07:25 +0200 Subject: Using salted MD5 checksums for the user's BitlBee password and salted RC4 encryption for the IM account passwords, plus some calls to srand() to keep the salts secure and unique. --- storage_xml.c | 77 +++++++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 59 insertions(+), 18 deletions(-) (limited to 'storage_xml.c') diff --git a/storage_xml.c b/storage_xml.c index 41a50d8c..35d74935 100644 --- a/storage_xml.c +++ b/storage_xml.c @@ -25,6 +25,8 @@ #define BITLBEE_CORE #include "bitlbee.h" +#include "base64.h" +#include "rc4.h" #include "md5.h" typedef enum @@ -77,32 +79,32 @@ static void xml_start_element( GMarkupParseContext *ctx, const gchar *element_na { char *nick = xml_attr( attr_names, attr_values, "nick" ); char *pass = xml_attr( attr_names, attr_values, "password" ); + md5_byte_t *pass_dec = NULL; if( !nick || !pass ) { g_set_error( error, G_MARKUP_ERROR, G_MARKUP_ERROR_INVALID_CONTENT, "Missing attributes for %s element", element_name ); } + else if( base64_decode( pass, &pass_dec ) != 21 ) + { + g_set_error( error, G_MARKUP_ERROR, G_MARKUP_ERROR_INVALID_CONTENT, + "Error while decoding password attribute" ); + } else { md5_byte_t pass_md5[16]; md5_state_t md5_state; - int i, j; + int i; md5_init( &md5_state ); md5_append( &md5_state, (md5_byte_t*) xd->given_pass, strlen( xd->given_pass ) ); + md5_append( &md5_state, (md5_byte_t*) pass_dec + 16, 5 ); /* Hmmm, salt! */ md5_finish( &md5_state, pass_md5 ); for( i = 0; i < 16; i ++ ) { - if( !isxdigit( pass[i*2] ) || !isxdigit( pass[i*2+1] ) || - sscanf( pass + i * 2, "%2x", &j ) != 1 ) - { - g_set_error( error, G_MARKUP_ERROR, G_MARKUP_ERROR_INVALID_CONTENT, - "Incorrect password MD5-hash" ); - break; - } - if( j != pass_md5[i] ) + if( pass_dec[i] != pass_md5[i] ) { g_set_error( error, G_MARKUP_ERROR, G_MARKUP_ERROR_INVALID_CONTENT, XML_PASS_ERRORMSG ); @@ -117,6 +119,8 @@ static void xml_start_element( GMarkupParseContext *ctx, const gchar *element_na xd->pass_st = XML_PASS_OK; } } + + g_free( pass_dec ); } else if( xd->pass_st < XML_PASS_OK ) { @@ -126,10 +130,12 @@ static void xml_start_element( GMarkupParseContext *ctx, const gchar *element_na else if( g_strcasecmp( element_name, "account" ) == 0 ) { char *protocol, *handle, *server, *password, *autoconnect; + char *pass_b64 = NULL, *pass_rc4 = NULL; + int pass_len; struct prpl *prpl = NULL; handle = xml_attr( attr_names, attr_values, "handle" ); - password = xml_attr( attr_names, attr_values, "password" ); + pass_b64 = xml_attr( attr_names, attr_values, "password" ); server = xml_attr( attr_names, attr_values, "server" ); autoconnect = xml_attr( attr_names, attr_values, "autoconnect" ); @@ -137,13 +143,15 @@ static void xml_start_element( GMarkupParseContext *ctx, const gchar *element_na if( protocol ) prpl = find_protocol( protocol ); - if( !handle || !password || !protocol ) + if( !handle || !pass_b64 || !protocol ) g_set_error( error, G_MARKUP_ERROR, G_MARKUP_ERROR_INVALID_CONTENT, "Missing attributes for %s element", element_name ); else if( !prpl ) g_set_error( error, G_MARKUP_ERROR, G_MARKUP_ERROR_INVALID_CONTENT, "Unknown protocol: %s", protocol ); - else + else if( ( pass_len = base64_decode( pass_b64, (unsigned char**) &pass_rc4 ) ) && + rc4_decode( (unsigned char*) pass_rc4, pass_len, + (unsigned char**) &password, xd->given_pass ) ) { xd->current_account = account_add( irc, prpl, handle, password ); if( server ) @@ -153,6 +161,16 @@ static void xml_start_element( GMarkupParseContext *ctx, const gchar *element_na a default! */ sscanf( autoconnect, "%d", &xd->current_account->auto_connect ); } + else + { + /* Actually the _decode functions don't even return error codes, + but maybe they will later... */ + g_set_error( error, G_MARKUP_ERROR, G_MARKUP_ERROR_INVALID_CONTENT, + "Error while decrypting account password" ); + } + + g_free( pass_rc4 ); + g_free( password ); } else if( g_strcasecmp( element_name, "setting" ) == 0 ) { @@ -353,12 +371,12 @@ static int xml_printf( int fd, char *fmt, ... ) static storage_status_t xml_save( irc_t *irc, int overwrite ) { - char path[512], *path2, md5_buf[33]; + char path[512], *path2, *pass_buf = NULL; set_t *set; nick_t *nick; account_t *acc; int fd, i; - md5_byte_t pass_md5[16]; + md5_byte_t pass_md5[21]; md5_state_t md5_state; if( irc->password == NULL ) @@ -379,15 +397,23 @@ static storage_status_t xml_save( irc_t *irc, int overwrite ) return STORAGE_OTHER_ERROR; } + /* Generate a salted md5sum of the password. Use 5 bytes for the salt + (to prevent dictionary lookups of passwords) to end up with a 21- + byte password hash, more convenient for base64 encoding. */ + for( i = 0; i < 5; i ++ ) + pass_md5[16+i] = rand() & 0xff; md5_init( &md5_state ); md5_append( &md5_state, (md5_byte_t*) irc->password, strlen( irc->password ) ); + md5_append( &md5_state, pass_md5 + 16, 5 ); /* Add the salt. */ md5_finish( &md5_state, pass_md5 ); - for( i = 0; i < 16; i ++ ) - g_snprintf( md5_buf + i * 2, 3, "%02x", pass_md5[i] ); + /* Save the hash in base64-encoded form. */ + pass_buf = base64_encode( (char*) pass_md5, 21 ); - if( !xml_printf( fd, "\n", irc->nick, md5_buf ) ) + if( !xml_printf( fd, "\n", irc->nick, pass_buf ) ) goto write_error; + g_free( pass_buf ); + for( set = irc->set; set; set = set->next ) if( set->value && set->def ) if( !xml_printf( fd, "\t%s\n", set->key, set->value ) ) @@ -395,8 +421,21 @@ static storage_status_t xml_save( irc_t *irc, int overwrite ) for( acc = irc->accounts; acc; acc = acc->next ) { - if( !xml_printf( fd, "\tprpl->name, acc->user, acc->pass, acc->auto_connect ) ) + char *pass_rc4, *pass_b64; + int pass_len; + + pass_len = rc4_encode( (unsigned char*) acc->pass, strlen( acc->pass ), (unsigned char**) &pass_rc4, irc->password ); + pass_b64 = base64_encode( pass_rc4, pass_len ); + + if( !xml_printf( fd, "\tprpl->name, acc->user, pass_b64, acc->auto_connect ) ) + { + g_free( pass_rc4 ); + g_free( pass_b64 ); goto write_error; + } + g_free( pass_rc4 ); + g_free( pass_b64 ); + if( acc->server && acc->server[0] && !xml_printf( fd, " server=\"%s\"", acc->server ) ) goto write_error; if( !xml_printf( fd, ">\n" ) ) @@ -432,6 +471,8 @@ static storage_status_t xml_save( irc_t *irc, int overwrite ) return STORAGE_OK; write_error: + g_free( pass_buf ); + irc_usermsg( irc, "Write error. Disk full?" ); close( fd ); -- cgit v1.2.3