Mercurial > hg > nginx
view src/core/ngx_sha1.c @ 7667:1ece2ac2555a
OCSP: fixed use-after-free on error.
When validating second and further certificates, ssl callback could be called
twice to report the error. After the first call client connection is
terminated and its memory is released. Prior to the second call and in it
released connection memory is accessed.
Errors triggering this behavior:
- failure to create the request
- failure to start resolving OCSP responder name
- failure to start connecting to the OCSP responder
The fix is to rearrange the code to eliminate the second call.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 15 Jun 2020 20:17:16 +0300 |
parents | 9eefb38f0005 |
children |
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/* * Copyright (C) Maxim Dounin * Copyright (C) Nginx, Inc. * * An internal SHA1 implementation. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_sha1.h> static const u_char *ngx_sha1_body(ngx_sha1_t *ctx, const u_char *data, size_t size); void ngx_sha1_init(ngx_sha1_t *ctx) { ctx->a = 0x67452301; ctx->b = 0xefcdab89; ctx->c = 0x98badcfe; ctx->d = 0x10325476; ctx->e = 0xc3d2e1f0; ctx->bytes = 0; } void ngx_sha1_update(ngx_sha1_t *ctx, const void *data, size_t size) { size_t used, free; used = (size_t) (ctx->bytes & 0x3f); ctx->bytes += size; if (used) { free = 64 - used; if (size < free) { ngx_memcpy(&ctx->buffer[used], data, size); return; } ngx_memcpy(&ctx->buffer[used], data, free); data = (u_char *) data + free; size -= free; (void) ngx_sha1_body(ctx, ctx->buffer, 64); } if (size >= 64) { data = ngx_sha1_body(ctx, data, size & ~(size_t) 0x3f); size &= 0x3f; } ngx_memcpy(ctx->buffer, data, size); } void ngx_sha1_final(u_char result[20], ngx_sha1_t *ctx) { size_t used, free; used = (size_t) (ctx->bytes & 0x3f); ctx->buffer[used++] = 0x80; free = 64 - used; if (free < 8) { ngx_memzero(&ctx->buffer[used], free); (void) ngx_sha1_body(ctx, ctx->buffer, 64); used = 0; free = 64; } ngx_memzero(&ctx->buffer[used], free - 8); ctx->bytes <<= 3; ctx->buffer[56] = (u_char) (ctx->bytes >> 56); ctx->buffer[57] = (u_char) (ctx->bytes >> 48); ctx->buffer[58] = (u_char) (ctx->bytes >> 40); ctx->buffer[59] = (u_char) (ctx->bytes >> 32); ctx->buffer[60] = (u_char) (ctx->bytes >> 24); ctx->buffer[61] = (u_char) (ctx->bytes >> 16); ctx->buffer[62] = (u_char) (ctx->bytes >> 8); ctx->buffer[63] = (u_char) ctx->bytes; (void) ngx_sha1_body(ctx, ctx->buffer, 64); result[0] = (u_char) (ctx->a >> 24); result[1] = (u_char) (ctx->a >> 16); result[2] = (u_char) (ctx->a >> 8); result[3] = (u_char) ctx->a; result[4] = (u_char) (ctx->b >> 24); result[5] = (u_char) (ctx->b >> 16); result[6] = (u_char) (ctx->b >> 8); result[7] = (u_char) ctx->b; result[8] = (u_char) (ctx->c >> 24); result[9] = (u_char) (ctx->c >> 16); result[10] = (u_char) (ctx->c >> 8); result[11] = (u_char) ctx->c; result[12] = (u_char) (ctx->d >> 24); result[13] = (u_char) (ctx->d >> 16); result[14] = (u_char) (ctx->d >> 8); result[15] = (u_char) ctx->d; result[16] = (u_char) (ctx->e >> 24); result[17] = (u_char) (ctx->e >> 16); result[18] = (u_char) (ctx->e >> 8); result[19] = (u_char) ctx->e; ngx_memzero(ctx, sizeof(*ctx)); } /* * Helper functions. */ #define ROTATE(bits, word) (((word) << (bits)) | ((word) >> (32 - (bits)))) #define F1(b, c, d) (((b) & (c)) | ((~(b)) & (d))) #define F2(b, c, d) ((b) ^ (c) ^ (d)) #define F3(b, c, d) (((b) & (c)) | ((b) & (d)) | ((c) & (d))) #define STEP(f, a, b, c, d, e, w, t) \ temp = ROTATE(5, (a)) + f((b), (c), (d)) + (e) + (w) + (t); \ (e) = (d); \ (d) = (c); \ (c) = ROTATE(30, (b)); \ (b) = (a); \ (a) = temp; /* * GET() reads 4 input bytes in big-endian byte order and returns * them as uint32_t. */ #define GET(n) \ ((uint32_t) p[n * 4 + 3] | \ ((uint32_t) p[n * 4 + 2] << 8) | \ ((uint32_t) p[n * 4 + 1] << 16) | \ ((uint32_t) p[n * 4] << 24)) /* * This processes one or more 64-byte data blocks, but does not update * the bit counters. There are no alignment requirements. */ static const u_char * ngx_sha1_body(ngx_sha1_t *ctx, const u_char *data, size_t size) { uint32_t a, b, c, d, e, temp; uint32_t saved_a, saved_b, saved_c, saved_d, saved_e; uint32_t words[80]; ngx_uint_t i; const u_char *p; p = data; a = ctx->a; b = ctx->b; c = ctx->c; d = ctx->d; e = ctx->e; do { saved_a = a; saved_b = b; saved_c = c; saved_d = d; saved_e = e; /* Load data block into the words array */ for (i = 0; i < 16; i++) { words[i] = GET(i); } for (i = 16; i < 80; i++) { words[i] = ROTATE(1, words[i - 3] ^ words[i - 8] ^ words[i - 14] ^ words[i - 16]); } /* Transformations */ STEP(F1, a, b, c, d, e, words[0], 0x5a827999); STEP(F1, a, b, c, d, e, words[1], 0x5a827999); STEP(F1, a, b, c, d, e, words[2], 0x5a827999); STEP(F1, a, b, c, d, e, words[3], 0x5a827999); STEP(F1, a, b, c, d, e, words[4], 0x5a827999); STEP(F1, a, b, c, d, e, words[5], 0x5a827999); STEP(F1, a, b, c, d, e, words[6], 0x5a827999); STEP(F1, a, b, c, d, e, words[7], 0x5a827999); STEP(F1, a, b, c, d, e, words[8], 0x5a827999); STEP(F1, a, b, c, d, e, words[9], 0x5a827999); STEP(F1, a, b, c, d, e, words[10], 0x5a827999); STEP(F1, a, b, c, d, e, words[11], 0x5a827999); STEP(F1, a, b, c, d, e, words[12], 0x5a827999); STEP(F1, a, b, c, d, e, words[13], 0x5a827999); STEP(F1, a, b, c, d, e, words[14], 0x5a827999); STEP(F1, a, b, c, d, e, words[15], 0x5a827999); STEP(F1, a, b, c, d, e, words[16], 0x5a827999); STEP(F1, a, b, c, d, e, words[17], 0x5a827999); STEP(F1, a, b, c, d, e, words[18], 0x5a827999); STEP(F1, a, b, c, d, e, words[19], 0x5a827999); STEP(F2, a, b, c, d, e, words[20], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[21], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[22], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[23], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[24], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[25], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[26], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[27], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[28], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[29], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[30], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[31], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[32], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[33], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[34], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[35], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[36], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[37], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[38], 0x6ed9eba1); STEP(F2, a, b, c, d, e, words[39], 0x6ed9eba1); STEP(F3, a, b, c, d, e, words[40], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[41], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[42], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[43], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[44], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[45], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[46], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[47], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[48], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[49], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[50], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[51], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[52], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[53], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[54], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[55], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[56], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[57], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[58], 0x8f1bbcdc); STEP(F3, a, b, c, d, e, words[59], 0x8f1bbcdc); STEP(F2, a, b, c, d, e, words[60], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[61], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[62], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[63], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[64], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[65], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[66], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[67], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[68], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[69], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[70], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[71], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[72], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[73], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[74], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[75], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[76], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[77], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[78], 0xca62c1d6); STEP(F2, a, b, c, d, e, words[79], 0xca62c1d6); a += saved_a; b += saved_b; c += saved_c; d += saved_d; e += saved_e; p += 64; } while (size -= 64); ctx->a = a; ctx->b = b; ctx->c = c; ctx->d = d; ctx->e = e; return p; }