It wasn't all that the critics wanted, but the Senate, on a 77 to 17 vote, approved legislation yesterday directing a major revamping of the federal tobacco support program.

The measure now returns for final action to the House, which last month passed a similar version. Rep. Charles Rose (D-N.C.), chief proponent of the bill, said he will attempt to get a House vote today.

Despite the changes--the most sweeping since Congress created the tobacco program in 1938--the bill underwent severe attacks by Sen. Thomas F. Eagleton (D-Mo.).

Eagleton, a two-packs-a-day cigarette smoker who denounced the "killer crop," charged that the alterations were "a cosmetic" and that the measure would not live up to its no-public-cost billing.

Eagleton's attack led to some colorfully soaring oratory, but when the smoke had cleared, tobacco-state forces had snuffed out two of his key proposed changes.

Led by Sens. Jesse A. Helms (R-N.C.) and Walter D. Huddleston (D-Ky.), the tobacco forces maintained that the bill was in effect an antitobacco measure and that to go any further would be to make it a punitive assault on thousands of small family farmers who raise flue-cured and burley leaf throughout the South.

One of Eagleton's amendments, tabled on a 56-to-40 vote, would have given the secretary of Agriculture more power to reduce price-support levels if it appeared program costs were going up.

The other, tabled 49 to 47 after Sen. Lloyd Bentsen (D-Tex.) broke a tie by switching his vote, would have ended tobacco's special legislative status and made it part of general farm legislation after 1985.

Nonetheless, the new approach adopted by the Senate orders major changes in the long-controversial program, which has been under increasing assault during the past three years.

The revision was directed by the 1981 farm bill, which called for a restructuring of the program to answer criticisms over its allotment system and to assure that it would be operated at no cost to the public.

As approved, the bill would continue the acreage allotment scheme that governs the program, but it would require a shift of most program costs from the federal government to individual tobacco farmers.

Beginning with the flue-cured crop that is about to go on the auction block in Deep South markets, farmers will be assessed about three cents a pound to finance a fund to pay for stockpiling of tobacco that is not sold. Government stockpiles now hold more than $400 million worth of medium- and low-grade leaf that many experts believe eventually will be unmarketable.

The bill would alter the allotment system by allowing nonfarming allotment holders to retain their government growing franchises, but it would require that schools, churches, corporations and other institutions surrender their allotments. Nonfarming allotment holders would be required to share farmers' tobacco-growing costs.

Although the legislation called for major changes in the program, one of Eagleton's main complaints was that those changes had been orchestrated by the tobacco-state legislators, whom he accused of trying to railroad the bill to passage.

Eagleton's objections to hurry-up procedures before the July 4 recess prevented the bill from being debated then and, in the eyes of Helms and Huddleston, had forced an unnecessary delay in opening of the flue-cured markets.

Eagleton argued that the rewritten program would not assure that taxpayers are relieved of underwriting the production and sale of what he called "a killer crop."