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Replace manual FFI symbol prefixing with automatic symbol prefixing.
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Revert the names used in the BoringSSL C/asm code to the names used in
BoringSSL. This substantially reduces the diff between *ring* and
BoringSSL for these files.

Use a variant of BoringSSL's symbol prefixing machinery to semi-
automatically prefix FFI symbols with the `GFp_` prefix. The names aren't
all exactly the same as before, because previously we *replaced* a
symbol's original prefix with the `GFp_` prefix; now we're prepending
`GFp_`. In the future we'll use a different prefix entirely.

This paves the way for using different prefixes for each version so that
multiple versions of *ring* can be linked into an executable at once.
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@briansmith
briansmith committed May 3, 2021
1 parent 4048eaa commit 384f7d0
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Showing 89 changed files with 1,301 additions and 1,020 deletions.
1 change: 1 addition & 0 deletions Cargo.toml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -214,6 +214,7 @@ include = [
"src/polyfill.rs",
"src/polyfill/array_map.rs",
"src/polyfill/chunks_fixed.rs",
"src/prefixed.rs",
"src/rand.rs",
"src/rsa/convert_nist_rsa_test_vectors.py",
"src/rsa.rs",
Expand Down
222 changes: 216 additions & 6 deletions build.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,7 @@

use std::{
fs::{self, DirEntry},
io::Write,
path::{Path, PathBuf},
process::Command,
};
Expand Down Expand Up @@ -329,6 +330,8 @@ fn pregenerate_asm_main() {
let pregenerated_tmp = pregenerated.join("tmp");
std::fs::create_dir(&pregenerated_tmp).unwrap();

let mut generated_prefix_headers = false;

for asm_target in ASM_TARGETS {
// For Windows, package pregenerated object files instead of
// pregenerated assembly language source files, so that the user
Expand All @@ -343,10 +346,13 @@ fn pregenerate_asm_main() {
perlasm(&perlasm_src_dsts, asm_target);

if asm_target.preassemble {
if !std::mem::replace(&mut generated_prefix_headers, true) {
generate_prefix_symbols_nasm(&pregenerated).unwrap();
}
let srcs = asm_srcs(perlasm_src_dsts);
for src in srcs {
let obj_path = obj_path(&pregenerated, &src, MSVC_OBJ_EXT);
run_command(nasm(&src, asm_target.arch, &obj_path));
run_command(nasm(&src, asm_target.arch, &obj_path, &pregenerated));
}
}
}
Expand Down Expand Up @@ -383,6 +389,8 @@ fn build_c_code(target: &Target, pregenerated: PathBuf, out_dir: &Path) {
out_dir
};

generate_prefix_symbols(target, out_dir).unwrap();

let asm_srcs = if let Some(asm_target) = asm_target {
let perlasm_src_dsts = perlasm_src_dsts(asm_dir, asm_target);

Expand Down Expand Up @@ -500,9 +508,9 @@ fn compile(p: &Path, target: &Target, warnings_are_errors: bool, out_dir: &Path)
let mut out_path = out_dir.join(p.file_name().unwrap());
assert!(out_path.set_extension(target.obj_ext));
let cmd = if target.os != WINDOWS || ext != "asm" {
cc(p, ext, target, warnings_are_errors, &out_path)
cc(p, ext, target, warnings_are_errors, &out_path, out_dir)
} else {
nasm(p, &target.arch, &out_path)
nasm(p, &target.arch, &out_path, out_dir)
};

run_command(cmd);
Expand All @@ -516,17 +524,23 @@ fn obj_path(out_dir: &Path, src: &Path, obj_ext: &str) -> PathBuf {
out_path
}

// This is the prefix we've been using for most symbols since we started
// prefixing.
const BORINGSSL_PREFIX_VALUE: &str = "GFp_";

fn cc(
file: &Path,
ext: &str,
target: &Target,
warnings_are_errors: bool,
out_dir: &Path,
out_path: &Path,
include_dir: &Path,
) -> Command {
let is_musl = target.env.starts_with("musl");

let mut c = cc::Build::new();
let _ = c.include("include");
let _ = c.include(include_dir);
match ext {
"c" => {
for f in c_flags(target) {
Expand Down Expand Up @@ -609,24 +623,35 @@ fn cc(
.arg(format!(
"{}{}",
target.obj_opt,
out_dir.to_str().expect("Invalid path")
out_path.to_str().expect("Invalid path")
))
.arg(file);
c
}

fn nasm(file: &Path, arch: &str, out_file: &Path) -> Command {
fn nasm(file: &Path, arch: &str, out_file: &Path, include_dir: &Path) -> Command {
let oformat = match arch {
"x86_64" => ("win64"),
"x86" => ("win32"),
_ => panic!("unsupported arch: {}", arch),
};

// Nasm requires that the path end in a path separator.
let mut include_dir = include_dir.as_os_str().to_os_string();
include_dir.push(std::ffi::OsString::from(String::from(
std::path::MAIN_SEPARATOR,
)));

let mut c = Command::new("./target/tools/windows/nasm/nasm");
let _ = c
.arg("-o")
.arg(out_file.to_str().expect("Invalid path"))
.arg("-f")
.arg(oformat)
.arg("-i")
.arg("include/")
.arg("-i")
.arg(include_dir)
.arg("-Xgnu")
.arg("-gcv8")
.arg(file);
Expand Down Expand Up @@ -766,3 +791,188 @@ fn walk_dir(dir: &Path, cb: &impl Fn(&DirEntry)) {
}
}
}

/// Creates the necessary header file for symbol renaming and returns the path of the
/// generated include directory.
fn generate_prefix_symbols(target: &Target, out_dir: &Path) -> Result<(), std::io::Error> {
generate_prefix_symbols_header(out_dir, "prefix_symbols.h", '#', None)?;

if target.os == "windows" {
let _ = generate_prefix_symbols_nasm(out_dir)?;
} else {
generate_prefix_symbols_header(
out_dir,
"prefix_symbols_asm.h",
'#',
Some("#if defined(__APPLE__)"),
)?;
}

Ok(())
}

fn generate_prefix_symbols_nasm(out_dir: &Path) -> Result<(), std::io::Error> {
generate_prefix_symbols_header(
out_dir,
"prefix_symbols_nasm.inc",
'%',
Some("%ifidn __OUTPUT_FORMAT__,win32"),
)
}

fn generate_prefix_symbols_header(
out_dir: &Path,
filename: &str,
pp: char,
prefix_condition: Option<&str>,
) -> Result<(), std::io::Error> {
let dir = out_dir.join("ring_core_generated");
std::fs::create_dir_all(&dir)?;

let path = dir.join(filename);
let mut file = std::fs::File::create(&path)?;

let filename_ident = filename.replace(".", "_").to_uppercase();
writeln!(
file,
r#"
{pp}ifndef GFp_generated_{filename_ident}
{pp}define GFp_generated_{filename_ident}
"#,
pp = pp,
filename_ident = filename_ident
)?;

if let Some(prefix_condition) = prefix_condition {
writeln!(file, "{}", prefix_condition)?;
writeln!(file, "{}", prefix_all_symbols(pp, "_"))?;
writeln!(file, "{pp}else", pp = pp)?;
};
writeln!(file, "{}", prefix_all_symbols(pp, ""))?;
if prefix_condition.is_some() {
writeln!(file, "{pp}endif", pp = pp)?
}

writeln!(file, "{pp}endif", pp = pp)?;

Ok(())
}

fn prefix_all_symbols(pp: char, prefix_prefix: &str) -> String {
static SYMBOLS_TO_PREFIX: &[&str] = &[
"CRYPTO_poly1305_finish",
"CRYPTO_poly1305_finish_neon",
"CRYPTO_poly1305_init",
"CRYPTO_poly1305_init_neon",
"CRYPTO_poly1305_update",
"CRYPTO_poly1305_update_neon",
"ChaCha20_ctr32",
"LIMBS_add_mod",
"LIMBS_are_even",
"LIMBS_are_zero",
"LIMBS_equal",
"LIMBS_equal_limb",
"LIMBS_less_than",
"LIMBS_less_than_limb",
"LIMBS_reduce_once",
"LIMBS_select_512_32",
"LIMBS_shl_mod",
"LIMBS_sub_mod",
"LIMBS_window5_split_window",
"LIMBS_window5_unsplit_window",
"LIMB_shr",
"OPENSSL_armcap_P",
"OPENSSL_cpuid_setup",
"OPENSSL_ia32cap_P",
"OPENSSL_memcmp",
"aes_hw_ctr32_encrypt_blocks",
"aes_hw_encrypt",
"aes_hw_set_encrypt_key",
"aes_nohw_ctr32_encrypt_blocks",
"aes_nohw_encrypt",
"aes_nohw_set_encrypt_key",
"aesni_gcm_decrypt",
"aesni_gcm_encrypt",
"bn_from_montgomery",
"bn_from_montgomery_in_place",
"bn_gather5",
"bn_mul_mont",
"bn_mul_mont_gather5",
"bn_neg_inv_mod_r_u64",
"bn_power5",
"bn_scatter5",
"bn_sqr8x_internal",
"bn_sqrx8x_internal",
"bsaes_ctr32_encrypt_blocks",
"bssl_constant_time_test_main",
"chacha20_poly1305_open",
"chacha20_poly1305_seal",
"gcm_ghash_avx",
"gcm_ghash_clmul",
"gcm_ghash_neon",
"gcm_gmult_clmul",
"gcm_gmult_neon",
"gcm_init_avx",
"gcm_init_clmul",
"gcm_init_neon",
"limbs_mul_add_limb",
"little_endian_bytes_from_scalar",
"nistz256_neg",
"nistz256_select_w5",
"nistz256_select_w7",
"nistz384_point_add",
"nistz384_point_double",
"nistz384_point_mul",
"p256_mul_mont",
"p256_point_add",
"p256_point_add_affine",
"p256_point_double",
"p256_point_mul",
"p256_point_mul_base",
"p256_scalar_mul_mont",
"p256_scalar_sqr_rep_mont",
"p256_sqr_mont",
"p384_elem_div_by_2",
"p384_elem_mul_mont",
"p384_elem_neg",
"p384_elem_sub",
"p384_scalar_mul_mont",
"poly1305_neon2_addmulmod",
"poly1305_neon2_blocks",
"sha256_block_data_order",
"sha512_block_data_order",
"vpaes_ctr32_encrypt_blocks",
"vpaes_encrypt",
"vpaes_encrypt_key_to_bsaes",
"vpaes_set_encrypt_key",
"x25519_NEON",
"x25519_fe_invert",
"x25519_fe_isnegative",
"x25519_fe_mul_ttt",
"x25519_fe_neg",
"x25519_fe_tobytes",
"x25519_ge_double_scalarmult_vartime",
"x25519_ge_frombytes_vartime",
"x25519_ge_scalarmult_base",
"x25519_public_from_private_generic_masked",
"x25519_sc_mask",
"x25519_sc_muladd",
"x25519_sc_reduce",
"x25519_scalar_mult_generic_masked",
];

let mut out = String::new();

for symbol in SYMBOLS_TO_PREFIX {
let line = format!(
"{pp}define {prefix_prefix}{symbol} {prefix_prefix}{prefix}{symbol}\n",
pp = pp,
prefix_prefix = prefix_prefix,
prefix = BORINGSSL_PREFIX_VALUE,
symbol = symbol
);
out += &line;
}

out
}
14 changes: 7 additions & 7 deletions crypto/chacha/asm/chacha-armv4.pl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -197,18 +197,18 @@ sub ROUND {
.Lone:
.long 1,0,0,0
#if __ARM_MAX_ARCH__>=7
.extern GFp_armcap_P
.hidden GFp_armcap_P
.extern OPENSSL_armcap_P
.hidden OPENSSL_armcap_P
.LOPENSSL_armcap:
.word GFp_armcap_P-.LChaCha20_ctr32
.word OPENSSL_armcap_P-.LChaCha20_ctr32
#else
.word -1
#endif

.globl GFp_ChaCha20_ctr32
.type GFp_ChaCha20_ctr32,%function
.globl ChaCha20_ctr32
.type ChaCha20_ctr32,%function
.align 5
GFp_ChaCha20_ctr32:
ChaCha20_ctr32:
.LChaCha20_ctr32:
ldr r12,[sp,#0] @ pull pointer to counter and nonce
stmdb sp!,{r0-r2,r4-r11,lr}
Expand Down Expand Up @@ -630,7 +630,7 @@ sub ROUND {
add sp,sp,#4*(32+3)
.Lno_data:
ldmia sp!,{r4-r11,pc}
.size GFp_ChaCha20_ctr32,.-GFp_ChaCha20_ctr32
.size ChaCha20_ctr32,.-ChaCha20_ctr32
___

{{{
Expand Down
18 changes: 9 additions & 9 deletions crypto/chacha/asm/chacha-armv8.pl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -122,8 +122,8 @@ sub ROUND {
$code.=<<___;
#include <GFp/arm_arch.h>

.extern GFp_armcap_P
.hidden GFp_armcap_P
.extern OPENSSL_armcap_P
.hidden OPENSSL_armcap_P

.section .rodata

Expand All @@ -136,20 +136,20 @@ sub ROUND {

.text

.globl GFp_ChaCha20_ctr32
.type GFp_ChaCha20_ctr32,%function
.globl ChaCha20_ctr32
.type ChaCha20_ctr32,%function
.align 5
GFp_ChaCha20_ctr32:
ChaCha20_ctr32:
AARCH64_VALID_CALL_TARGET
cbz $len,.Labort
#if __has_feature(hwaddress_sanitizer) && __clang_major__ >= 10
adrp @x[0],:pg_hi21_nc:GFp_armcap_P
adrp @x[0],:pg_hi21_nc:OPENSSL_armcap_P
#else
adrp @x[0],:pg_hi21:GFp_armcap_P
adrp @x[0],:pg_hi21:OPENSSL_armcap_P
#endif
cmp $len,#192
b.lo .Lshort
ldr w17,[@x[0],:lo12:GFp_armcap_P]
ldr w17,[@x[0],:lo12:OPENSSL_armcap_P]
tst w17,#ARMV7_NEON
b.ne ChaCha20_neon

Expand Down Expand Up @@ -334,7 +334,7 @@ sub ROUND {
ldp x29,x30,[sp],#96
AARCH64_VALIDATE_LINK_REGISTER
ret
.size GFp_ChaCha20_ctr32,.-GFp_ChaCha20_ctr32
.size ChaCha20_ctr32,.-ChaCha20_ctr32
___

{{{
Expand Down
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