- cypherpunks-legacy - lists.cpunks.org

Re: Did you *really* zeroize that key?
by Patrick Chkoreff 08 Nov '02

08 Nov '02

>From: "Trei, Peter" <ptrei(a)rsasecurity.com> > >[Moderator's note: FYI: no "pragma" is needed. This is what C's >"volatile" keyword is for. Unfortunately, not everyone writing in C >knows the language. --Perry] Thanks for the reminder about "volatile." It is an ancient and valuable feature of C and I suppose it's implemented correctly under gcc and some of the Windoze compilers even with high optimization options like -O2. > >From RISKS: >http://catless.ncl.ac.uk/Risks/22.35.html#subj6 > >Those of us who write code need to be reminded of this >now and then. Everybody probably also knows about the gnupg trick, where they define a recursive routine called "burn_stack": static void burn_stack (int bytes) { char buf[64]; memset (buf, 0, sizeof buf); bytes -= sizeof buf; if (bytes > 0) burn_stack (bytes); } Then there's the vararg technique discussed in Michael Welschenbach's book "Cryptography in C and C++": static void purgevars_l (int noofvars, ...) { va_list ap; size_t size; va_start (ap, noofvars); for (; noofvars > 0; --noofvars) { switch (size = va_arg (ap, size_t)) { case 1: *va_arg (ap, char *) = 0; break; case 2: *va_arg (ap, short *) = 0; break; case 4: *va_arg (ap, long *) = 0; break; default: memset (va_arg(ap, char *), 0, size); } } va_end (ap); } Here's an example of how you might call the routine: purgevars_l(2, sizeof (la), &la, sizeof (lb), &lb); But hey, if "volatile" keyword works then so much the better. I would recommend examining the assembly language output of your compiler to verify that it honours "volatile." -- Patrick http://fexl.com

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US Airways E-Savers to Frankfurt
by ESavers＠usairways.com 08 Nov '02

08 Nov '02

Dear E-Savers Subscriber, US Airways is pleased to present this special International E-Savers offer: ************************************************************ 1. This Week's International E-Savers 2. US Airways Vacations Deals 3. Dividend Miles Offers 4. E-Savers Fare Requirements 5. Subscription Information ************************************************************ 1. THIS WEEK'S INTERNATIONAL E-SAVERS ************************************************************ You may depart on Sundays to Thursdays, between November 10 and November 28, 2002. Return travel is Mondays to Fridays, between November 18 and December 6, 2002. Travel is not permitted to Frankfurt on November 27. Travel is not permitted from Frankfurt on December 2. Saturday night stay is required. Tickets must be purchased by November 13, 2002. For travel, make your reservations online at http://www.usairways.com/promotions/esavers/offer_fra.htm These special fares can also be purchased by calling 1-888-359-3728. Tickets must be purchased at the time of reservation. For more information on Frankfurt, please visit http://www.usairways.com/travel/destinations/europe/fra.htm ROUNDTRIP FROM: TO: FARE: ------------------------------------------------------------- Baltimore, MD Frankfurt, Germany $255 Boston, MA Frankfurt, Germany $255 Buffalo, NY Frankfurt, Germany $265 Charlotte, NC Frankfurt, Germany $235 Columbus, OH Frankfurt, Germany $285 Greensboro, NC Frankfurt, Germany $265 Greenville/Spart., SC Frankfurt, Germany $265 Hartford, CT Frankfurt, Germany $255 Indianapolis, IN Frankfurt, Germany $285 Los Angeles, CA Frankfurt, Germany $315 New York LaGuardia, NY Frankfurt, Germany $255 Philadelphia, PA Frankfurt, Germany $235 Pittsburgh, PA Frankfurt, Germany $235 Providence, RI Frankfurt, Germany $255 Raleigh/Durham, NC Frankfurt, Germany $265 Richmond, VA Frankfurt, Germany $265 Rochester, NY Frankfurt, Germany $265 San Francisco, CA Frankfurt, Germany $315 Syracuse, NY Frankfurt, Germany $265 Washington National, DC Frankfurt, Germany $255 Fares shown are based on roundtrip Coach travel on US Airways/US Airways Express, during the period specified above. Depending upon your travel needs, alternative routings may be available at the same fares, with part of the service on regional aircraft operated by US Airways Express carriers Allegheny, Air Midwest, CCAIR, Chautauqua, Colgan, Mesa, Piedmont, PSA, Shuttle America or Trans States. ************************************************************ 2. US AIRWAYS VACATIONS DEALS ************************************************************ US Airways Vacations is pleased to offer Frankfurt land packages to provide a complete vacation experience. Vacations include hotel accommodations, breakfast daily, hotel taxes and service charges. A variety of optional features including attraction admissions and sightseeing tours are available. US Airways Vacations offers packages to 80+ destinations. EXPERIENCE FRANKFURT!!! ----------------------- Land only based on per person, per night from: Excelsior $47 Heidelberg Marriott $57 Monopol $62 Rudesheimer Schloss - Rudesheim am Rhein $77 Purchase these land packages online at http://www.usairwaysvacations.com/pricing_res.htm Simply enter your origin and destination cities, departure date, number of adults, children's ages and click "Search For Vacation." Choose "Hotel Vacations for 1-59 nights," confirm your departure date and indicate the number of nights for your vacation. Click "Check Availability" and continue with your choices for hotels and options as the system presents them until you reach the final price. You may then purchase your vacation with a secure credit card transaction. If you prefer to speak with a reservations agent, call 1-800-352-8747. Rates shown are per person, per night based on double occupancy for departures 11/10/02 through 12/6/02. Hotel space is limited and may not be available at all hotels on all days. Additional travel dates, hotels and rates are available. Prices are subject to change with or without notice and do not include miscellaneous hotel charges typically paid by the customer directly to the hotel. Substantial restrictions apply for refunds. Other conditions may apply. ************************************************************ 3. DIVIDEND MILES OFFERS - EARN 500 MILES WITH E-STATEMENTS ************************************************************ "Sign Up For E-Statements, Get 500 Miles" If you like E-Savers, you will really like Dividend Miles E-Statements. E-Statements are sent monthly via e-mail and include your account summary along with exclusive bonus mile offers, US Airways news, special discount travel awards and other offers. Earn 500 miles when you sign up for E-Statements at usairways.com/estatements now through December 31, 2002. E-Statements = More Miles, More Offers, More Awards and Your Statement, More Often." Reminder: Make sure your Dividend Miles account number is in your E-Savers reservation, so you can earn miles for worldwide award travel on US Airways and our partners. To enroll in Dividend Miles, go to http://www.usairways.com/ To earn even more miles, book E-Savers using your US Airways Dividend Miles Visa card. To apply for the Dividend Miles Visa card issued by Bank of America, please visit us at http://www.usairways.com/dmcreditcards Please note: Mileage bonus for booking online does not apply to E-Savers. ************************************************************ 4. E-SAVERS FARE REQUIREMENTS ************************************************************ - Restrictions: Roundtrip purchase required. Seats are limited and are not available on all flights/days. Fares cannot be combined with other fares, discounts, promotions or coupons. Travel must begin and end in the same city. One-way travel, stopovers, waitlisting and standbys are not permitted. Tickets must be purchased at the time of reservation. Fares will not be honored retroactively or in conjunction with the exchange of any partially used ticket. - Travel: Depart to Frankfurt 11/10-11/28/02, Sunday-Thursday, and return from Frankfurt 11/18-12/6/02, Monday-Friday, except for the following blackout dates: Travel is not permitted to Frankfurt on November 27 and travel is not permitted from Frankfurt on December 2. Saturday night stay required. All travel must be completed by 12/6/02. - Ticketing: Tickets must be purchased by 11/13/02. - Taxes/Fees: Depending on the itinerary, passenger facility charges of up to $18 and the September 11th Security Fee of up to $10 may apply in addition to the fare. Fares shown do not include total government-imposed taxes/fees/surcharges of up to $105. - Changes: Tickets become non-refundable 24 hours after making initial reservation, and may be changed prior to the departure of each flight segment for a minimum $200 fee. If changes are not made prior to the departure date/time of each flight, the entire remaining ticket will have no further value. - Miscellaneous: Lower fares may be available in these markets. Other conditions apply. ************************************************************ 5. SUBSCRIPTION INFORMATION ************************************************************ This is a post-only mailing sent to CYPHERPUNKS(a)ALGEBRA.COM. If you would like to change your e-mail address, you will need to unsubscribe and resubscribe at the E-Savers Enrollment page: http://www.usairways.com/promotions/esavers/enroll/index.htm To unsubscribe from this list, please click here: http://www.usairways.com/cgi-bin/delete.cgi?email=CYPHERPUNKS@ALGEBRA.COM To change your departure city preferences, please visit: http://www.usairways.com/promotions/esavers/enroll/index.htm Please do not respond to this message. Copyright US Airways 1996-2002. All rights reserved.

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US Airways E-Savers to Frankfurt
by ESavers＠usairways.com 08 Nov '02

08 Nov '02

Dear E-Savers Subscriber, US Airways is pleased to present this special International E-Savers offer: ************************************************************ 1. This Week's International E-Savers 2. US Airways Vacations Deals 3. Dividend Miles Offers 4. E-Savers Fare Requirements 5. Subscription Information ************************************************************ 1. THIS WEEK'S INTERNATIONAL E-SAVERS ************************************************************ You may depart on Sundays to Thursdays, between November 10 and November 28, 2002. Return travel is Mondays to Fridays, between November 18 and December 6, 2002. Travel is not permitted to Frankfurt on November 27. Travel is not permitted from Frankfurt on December 2. Saturday night stay is required. Tickets must be purchased by November 13, 2002. For travel, make your reservations online at http://www.usairways.com/promotions/esavers/offer_fra.htm These special fares can also be purchased by calling 1-888-359-3728. Tickets must be purchased at the time of reservation. For more information on Frankfurt, please visit http://www.usairways.com/travel/destinations/europe/fra.htm ROUNDTRIP FROM: TO: FARE: ------------------------------------------------------------- Baltimore, MD Frankfurt, Germany $255 Boston, MA Frankfurt, Germany $255 Buffalo, NY Frankfurt, Germany $265 Charlotte, NC Frankfurt, Germany $235 Columbus, OH Frankfurt, Germany $285 Greensboro, NC Frankfurt, Germany $265 Greenville/Spart., SC Frankfurt, Germany $265 Hartford, CT Frankfurt, Germany $255 Indianapolis, IN Frankfurt, Germany $285 Los Angeles, CA Frankfurt, Germany $315 New York LaGuardia, NY Frankfurt, Germany $255 Philadelphia, PA Frankfurt, Germany $235 Pittsburgh, PA Frankfurt, Germany $235 Providence, RI Frankfurt, Germany $255 Raleigh/Durham, NC Frankfurt, Germany $265 Richmond, VA Frankfurt, Germany $265 Rochester, NY Frankfurt, Germany $265 San Francisco, CA Frankfurt, Germany $315 Syracuse, NY Frankfurt, Germany $265 Washington National, DC Frankfurt, Germany $255 Fares shown are based on roundtrip Coach travel on US Airways/US Airways Express, during the period specified above. Depending upon your travel needs, alternative routings may be available at the same fares, with part of the service on regional aircraft operated by US Airways Express carriers Allegheny, Air Midwest, CCAIR, Chautauqua, Colgan, Mesa, Piedmont, PSA, Shuttle America or Trans States. ************************************************************ 2. US AIRWAYS VACATIONS DEALS ************************************************************ US Airways Vacations is pleased to offer Frankfurt land packages to provide a complete vacation experience. Vacations include hotel accommodations, breakfast daily, hotel taxes and service charges. A variety of optional features including attraction admissions and sightseeing tours are available. US Airways Vacations offers packages to 80+ destinations. EXPERIENCE FRANKFURT!!! ----------------------- Land only based on per person, per night from: Excelsior $47 Heidelberg Marriott $57 Monopol $62 Rudesheimer Schloss - Rudesheim am Rhein $77 Purchase these land packages online at http://www.usairwaysvacations.com/pricing_res.htm Simply enter your origin and destination cities, departure date, number of adults, children's ages and click "Search For Vacation." Choose "Hotel Vacations for 1-59 nights," confirm your departure date and indicate the number of nights for your vacation. Click "Check Availability" and continue with your choices for hotels and options as the system presents them until you reach the final price. You may then purchase your vacation with a secure credit card transaction. If you prefer to speak with a reservations agent, call 1-800-352-8747. Rates shown are per person, per night based on double occupancy for departures 11/10/02 through 12/6/02. Hotel space is limited and may not be available at all hotels on all days. Additional travel dates, hotels and rates are available. Prices are subject to change with or without notice and do not include miscellaneous hotel charges typically paid by the customer directly to the hotel. Substantial restrictions apply for refunds. Other conditions may apply. ************************************************************ 3. DIVIDEND MILES OFFERS - EARN 500 MILES WITH E-STATEMENTS ************************************************************ "Sign Up For E-Statements, Get 500 Miles" If you like E-Savers, you will really like Dividend Miles E-Statements. E-Statements are sent monthly via e-mail and include your account summary along with exclusive bonus mile offers, US Airways news, special discount travel awards and other offers. Earn 500 miles when you sign up for E-Statements at usairways.com/estatements now through December 31, 2002. E-Statements = More Miles, More Offers, More Awards and Your Statement, More Often." Reminder: Make sure your Dividend Miles account number is in your E-Savers reservation, so you can earn miles for worldwide award travel on US Airways and our partners. To enroll in Dividend Miles, go to http://www.usairways.com/ To earn even more miles, book E-Savers using your US Airways Dividend Miles Visa card. To apply for the Dividend Miles Visa card issued by Bank of America, please visit us at http://www.usairways.com/dmcreditcards Please note: Mileage bonus for booking online does not apply to E-Savers. ************************************************************ 4. E-SAVERS FARE REQUIREMENTS ************************************************************ - Restrictions: Roundtrip purchase required. Seats are limited and are not available on all flights/days. Fares cannot be combined with other fares, discounts, promotions or coupons. Travel must begin and end in the same city. One-way travel, stopovers, waitlisting and standbys are not permitted. Tickets must be purchased at the time of reservation. Fares will not be honored retroactively or in conjunction with the exchange of any partially used ticket. - Travel: Depart to Frankfurt 11/10-11/28/02, Sunday-Thursday, and return from Frankfurt 11/18-12/6/02, Monday-Friday, except for the following blackout dates: Travel is not permitted to Frankfurt on November 27 and travel is not permitted from Frankfurt on December 2. Saturday night stay required. All travel must be completed by 12/6/02. - Ticketing: Tickets must be purchased by 11/13/02. - Taxes/Fees: Depending on the itinerary, passenger facility charges of up to $18 and the September 11th Security Fee of up to $10 may apply in addition to the fare. Fares shown do not include total government-imposed taxes/fees/surcharges of up to $105. - Changes: Tickets become non-refundable 24 hours after making initial reservation, and may be changed prior to the departure of each flight segment for a minimum $200 fee. If changes are not made prior to the departure date/time of each flight, the entire remaining ticket will have no further value. - Miscellaneous: Lower fares may be available in these markets. Other conditions apply. ************************************************************ 5. SUBSCRIPTION INFORMATION ************************************************************ This is a post-only mailing sent to CYPHERPUNKS(a)ALGEBRA.COM. If you would like to change your e-mail address, you will need to unsubscribe and resubscribe at the E-Savers Enrollment page: http://www.usairways.com/promotions/esavers/enroll/index.htm To unsubscribe from this list, please click here: http://www.usairways.com/cgi-bin/delete.cgi?email=CYPHERPUNKS@ALGEBRA.COM To change your departure city preferences, please visit: http://www.usairways.com/promotions/esavers/enroll/index.htm Please do not respond to this message. Copyright US Airways 1996-2002. All rights reserved.

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AECWorkForce Professional News (November 8, 2002)
by AECWorkForce Professional News 08 Nov '02

08 Nov '02

=========================================================================== AECWorkForce Professional News Where great careers in design and construction are built http://www.AECWorkForce.com ========================================================================== Friday, November 8, 2002 THIS WEEK 1. JOB SEARCH STRATEGIES - RESIGNING PROFESSIONALLY 2. AEC CAREER TRENDS - STAYING ON TOP OF THE JOB MARKET 3. CAREER MENTOR - "IS THIS GOING TO BE ON THE TEST?" 4. HOT FIRM - TRANSYSTEMS CORPORATION 5. HOT JOBS - MORE HOT LISTINGS FROM AECWORKFORCE.COM Questions about your subscription to AECWorkForce Professional News? Check the end of this message for information. *********************************************************** 1. AEC JOB SEARCH STRATEGIES RESIGNING PROFESSIONALLY So you've finally decided to quit your lousy job. Here are some tips on how to keep your professionalism intact during your resignation. MORE: http://www.aecworkforce.com/magazine/jobsearch/current.htm 2. AEC CAREER TRENDS STAYING ON TOP OF THE JOB MARKET Today, more and more qualified, experienced professionals are actively testing the job market to see what it has to offer-while they're still employed. Learn why that's not a bad idea. MORE: http://www.aecworkforce.com/magazine/careers/current.htm ADVERTISEMENT ********************************************** NEW! A CAREER GUIDE JUST FOR DESIGN AND CONSTRUCTION PROS ONLY $23.95! Are you looking for a new job in the design and construction field? Then the AECWorkForce Guide to Finding the Right Job in the Design & Construction Industry is the perfect resource! From the job search experts at AECWorkForce.com, this guide is a must-have for any AEC industry job seeker looking for an edge. To learn more, visit us online at http://www.aecworkforce.com/guide *********************************************************** 3. AEC CAREER MENTOR "IS THIS GOING TO BE ON THE TEST?" Dear AEC Career Mentor: Recently, I interviewed with a great firm for the position of project manager. I have the experience, but they want me to take a WRITING TEST! I'm bugged-is this the norm? MORE: http://www.aecworkforce.com/magazine/mentor/current.htm 4. HOT FIRM TRANSYSTEMS CORPORATION KANSAS CITY, MO With 700 employees and 26 offices, TranSystems Corporation has been a leader in providing nationwide transportation engineering, planning and architectural services for over 30 years. Their dynamic, entrepreneurial environment has created engineering opportunities for entry-level and experienced professionals in their offices throughout the United States. Learn more about this hot firm by clicking here: http://www.aecworkforce.com/cgi-bin/wc.dll?Enter~?ShowProfile~_0B212XIA7 5. 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Can you handle the TRUTH? Code: qsxsu
by bewe--The Editors 08 Nov '02

08 Nov '02

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cypherpunks, Refinance with bad credit! 2700 lender network can help
by Harold Coppedge 08 Nov '02

08 Nov '02

Sorry about that. My hosting went down I had hosting problems: http://www.votersurvey.com/ms2/index.htm Do you have tons of debts and want to refinance_your home I guaruntee that I can do it fast and easy and your credit score doesn't matter! Please just fill out this form and I'll call you immediately. http://www.votersurvey.com/ms2/index.htm I have more credit programs than the large companies. You will not be dissappointed. I'll work my butt off for you!!!!!! Roger Staples

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Re: Did you *really* zeroize that key?
by Patrick Chkoreff 08 Nov '02

08 Nov '02

>>From: "Trei, Peter" <ptrei(a)rsasecurity.com> >> >>[Moderator's note: FYI: no "pragma" is needed. This is what C's >>"volatile" keyword is for. Unfortunately, not everyone writing in C >>knows the language. --Perry] > >Thanks for the reminder about "volatile." It is an ancient and valuable >feature of C and I suppose it's implemented correctly under gcc and some >of the Windoze compilers even with high optimization options like -O2. Oops, I missed your real point, which is that "volatile" ought to suffice as a compiler guide and there is no need for an additional pragma. By declaring a variable as volatile, the compiler would also leave untouched any code which refers to that variable. Too bad that volatile is not guaranteed to work in all major ANSI-compliant compilers. Oh well. I wonder how gcc does with it? [Moderator's note: I've quoted chapter and verse -- if it follows the current standards, it is required to honor "volatile". It isn't compliant by definition if it does not. gcc does indeed honor "volatile", as do almost all other C compilers I have access to. --Perry] I guess we should stick with either the recursive routine trick or the var-arg trick. -- Patrick http://fexl.com --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majordomo(a)wasabisystems.com

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Re: Did you *really* zeroize that key?
by Kevin Elliott 07 Nov '02

07 Nov '02

At 19:30 +0000 on 11/7/02, David Howe wrote: >at Thursday, November 07, 2002 6:13 PM, David Honig <dahonig(a)cox.net> >was seen to say: >> Wouldn't a crypto coder be using paranoid-programming >> skills, like *checking* that the memory is actually zeroed? >That is one of the workarounds yes - but of course a (theoretical) >clever compiler could realise that > >int myflag; >myflag=0; >if (myflag!=0) { do stuff } ; > >can be optimised away entirely as the result is constant. > >the problem isn't so much a question of what would work now, but "is it >possible that your zeros could be optimised away by a theoretical future >compiler, and how do we make portable code that nevertheless can't be >optimised away?" The point is though, that according to C99 today volatile int myflag; myflag=0; if (myflag!=0) { do stuff } ; does _exactly_ what you want, per the spec. The only compilers that don't work this way are by definition out of spec, so adding new stuff isn't going to help. Having said that, most of what your talking about pragma wise is boils down to controlling the optimizer. Most compilers offer options to control this, but it's vendor specific. I can see how adding this to the spec would be worthwhile. But it's not essential to fix the problem above. -- _____________________________________________ Kevin Elliott <mailto:kelliott@mac.com> ICQ#23758827

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RE: Did you *really* zeroize that key?
by Trei, Peter 07 Nov '02

07 Nov '02

> ---------- > From: Dave Howe[SMTP:DaveHowe@gmx.co.uk] > Sent: Thursday, November 07, 2002 3:46 PM > To: Email List: Cypherpunks > Subject: Re: Did you *really* zeroize that key? > > David Honig wrote: > > I was thinking more in terms of arrays > > > > memset( arr, 0, sizeof(arr)) // zero > > unsigned int v=1; > > for (int i=0; i< arr_size; i++) v += arr[i]; // check > > if ( v>0 && v<2 ) // test > > sanity(); > > else > > insanity(); > > > > But I suppose that if compilers can be arbitrarily 'clever' > > (eg about memset() and the additive properties of zero) > > you'll have to check the assembly code... > > > > Perhaps > > > > for (int i=0; i< arr_size; i++) arr[i]=i; // "zero" > > unsigned int v=0; > > for (i=0; i< arr_size; i++) v += arr[i]; // check > > if ( v != expected_value( arr_size ) ) insanity(); > > else sanity(); > > > > is better? (In the sense that this code will be treated > > as worth-keeping.) > as an abstract, probably not - there is always a chance that *any* given > structure will be optimised away in a future compiler that is both > arbitarily "smart" but stupid enough not to understand you are going to > extreme effort to try and avoid the optimiser removing a clear. > about all I can think of that could not be optimised away would be a > dynamic > library call - if a library call "int clearthismem(void pointer*, long > lengthinbytes);" is used, as the optimising compiler can't look inside the > code for it to see exactly what it does with the passed variable, it can't > optimise it away - and the compiler that compiled the "blank passed mem to > zero" code won't know that it isn't used once the subroutine is exited > (and > in fact, it could also be used as a convenient way to force-initialise an > array or string to zeros if execution time wasn't an issue) > The #pragma fixes are good, but non-portable. None of the portable fixes can be trusted against an arbitrarily smart optimizer. and they have space and performance hits. The 'volatile' keyword seems to have poorly defined behaviour. Perhaps the next 'C' standard needs a new keyword, 'always' which tells the compiler that this line *must* be included: always memset(arr,0,sizeof(arr)); ...but this seems to break the rules, in that it's really a standard-defined #pragma in disguise. This is one fun Heisenbug :-) Peter

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Amerikan Military: All Your Children Are Belong To Us
by Major Variola (ret) 07 Nov '02

07 Nov '02

Sharon Shea-Keneally, principal of Mount Anthony Union High School in Bennington, Vermont, was shocked when she received a letter in May from military recruiters demanding a list of all her students, including names, addresses, and phone numbers. The school invites recruiters to participate in career days and job fairs, but like most school districts, it keeps student information strictly confidential. "We don't give out a list of names of our kids to anybody," says Shea-Keneally, "not to colleges, churches, employers -- nobody." But when Shea-Keneally insisted on an explanation, she was in for an even bigger surprise: The recruiters cited the No Child Left Behind Act, President Bush's sweeping new education law passed earlier this year. There, buried deep within the law's 670 pages, is a provision requiring public secondary schools to provide military recruiters not only with access to facilities, but also with contact information for every student -- or face a cutoff of all federal aid. <snip> http://www.motherjones.com/news/outfront/2002/45/ma_153_01.html

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