lighttpd 1.4.x
https://www.lighttpd.net/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
174 lines
6.6 KiB
174 lines
6.6 KiB
#include "first.h" |
|
|
|
#include "base64.h" |
|
|
|
/* reverse mapping: |
|
* >= 0: base64 value |
|
* -1: invalid character |
|
* -2: skip character (whitespace/control) |
|
* -3: padding |
|
*/ |
|
|
|
/* BASE64_STANDARD: "A-Z a-z 0-9 + /" maps to 0-63, pad with "=" */ |
|
static const char base64_standard_table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/="; |
|
static const signed char base64_standard_reverse_table[] = { |
|
/* 0 1 2 3 4 5 6 7 8 9 A B C D E F */ |
|
-1, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, /* 0x00 - 0x0F */ |
|
-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, /* 0x10 - 0x1F */ |
|
-2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, /* 0x20 - 0x2F */ |
|
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -3, -1, -1, /* 0x30 - 0x3F */ |
|
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, /* 0x40 - 0x4F */ |
|
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, /* 0x50 - 0x5F */ |
|
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, /* 0x60 - 0x6F */ |
|
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1, /* 0x70 - 0x7F */ |
|
}; |
|
|
|
/* BASE64_URL: "A-Z a-z 0-9 - _" maps to 0-63, pad with "." */ |
|
static const char base64_url_table[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_."; |
|
static const signed char base64_url_reverse_table[] = { |
|
/* 0 1 2 3 4 5 6 7 8 9 A B C D E F */ |
|
-1, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, /* 0x00 - 0x0F */ |
|
-2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, /* 0x10 - 0x1F */ |
|
-2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -3, -1, /* 0x20 - 0x2F */ |
|
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, /* 0x30 - 0x3F */ |
|
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, /* 0x40 - 0x4F */ |
|
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, 63, /* 0x50 - 0x5F */ |
|
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, /* 0x60 - 0x6F */ |
|
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1, /* 0x70 - 0x7F */ |
|
}; |
|
|
|
static size_t li_base64_dec(unsigned char * const result, const size_t out_length, const char * const in, const size_t in_length, const base64_charset charset) { |
|
size_t i; |
|
const signed char * const base64_reverse_table = (charset) |
|
? base64_url_reverse_table /* BASE64_URL */ |
|
: base64_standard_reverse_table; /* BASE64_STANDARD */ |
|
|
|
int_fast32_t ch = 0; |
|
int_fast32_t out4 = 0; |
|
size_t out_pos = 0; |
|
for (i = 0; i < in_length; i++) { |
|
const uint_fast32_t c = ((unsigned char *)in)[i]; |
|
ch = (c < 128) ? base64_reverse_table[c] : -1; |
|
if (__builtin_expect( (ch < 0), 0)) { |
|
/* skip formatted base64; skip whitespace ('\r' '\n' '\t' ' ')*/ |
|
if (-2 == ch) /*(loose check; skip ' ', all ctrls not \127 or \0)*/ |
|
continue; /* skip character */ |
|
break; |
|
} |
|
|
|
out4 = (out4 << 6) | ch; |
|
if ((i & 3) == 3) { |
|
result[out_pos] = (out4 >> 16) & 0xFF; |
|
result[out_pos+1] = (out4 >> 8) & 0xFF; |
|
result[out_pos+2] = (out4 ) & 0xFF; |
|
out_pos += 3; |
|
out4 = 0; |
|
} |
|
} |
|
|
|
/* permit base64 string ending with pad chars (ch == -3); not checking |
|
* for one or two pad chars + optional whitespace reaches in_length) */ |
|
/* permit base64 string truncated before in_length (in[i] == '\0') */ |
|
switch (i == in_length || ch == -3 || in[i] != '\0' ? (i & 3) : 1) { |
|
case 3: |
|
result[out_pos++] = (out4 >> 10); |
|
out4 <<= 2; |
|
__attribute_fallthrough__ |
|
case 2: |
|
result[out_pos++] = (out4 >> 4) & 0xFF; |
|
__attribute_fallthrough__ |
|
case 0: |
|
force_assert(out_pos <= out_length); |
|
return out_pos; |
|
case 1: /* pad char or str end can only come after 2+ base64 chars */ |
|
default: |
|
return 0; /* invalid character, abort */ |
|
} |
|
} |
|
|
|
size_t li_base64_enc(char * const restrict out, const size_t out_length, const unsigned char * const restrict in, const size_t in_length, const base64_charset charset, const int pad) { |
|
size_t i; |
|
size_t out_pos = 0; |
|
uint_fast32_t v; |
|
const char* const base64_table = (charset) |
|
? base64_url_table /* BASE64_URL */ |
|
: base64_standard_table; /* BASE64_STANDARD */ |
|
const char padchar = base64_table[64]; /* padding char */ |
|
|
|
/* check overflows */ |
|
/* 1073741823 is max num full_tuples to avoid overflow in uint32_t; |
|
* and (1 GB - 1) is ridiculously large for base64-encoded data */ |
|
force_assert(in_length <= 3221225469); /* (3221225469+2) / 3 * 4 < UINT32_MAX */ |
|
force_assert((in_length+2)/3*4 <= out_length); |
|
|
|
for (i = 2; i < in_length; i += 3) { |
|
v = (in[i-2] << 16) | (in[i-1] << 8) | in[i]; |
|
out[out_pos+0] = base64_table[(v >> 18) & 0x3f]; |
|
out[out_pos+1] = base64_table[(v >> 12) & 0x3f]; |
|
out[out_pos+2] = base64_table[(v >> 6) & 0x3f]; |
|
out[out_pos+3] = base64_table[(v ) & 0x3f]; |
|
out_pos += 4; |
|
} |
|
|
|
switch (in_length - (i-2)) { |
|
case 0: |
|
default: |
|
break; |
|
case 1: |
|
{ |
|
/* pretend in[i-1] = in[i] = 0, don't write last two (out_pos+3, out_pos+2) characters */ |
|
v = (in[i-2] << 4); |
|
out[out_pos+0] = base64_table[(v >> 6) & 0x3f]; |
|
out[out_pos+1] = base64_table[(v ) & 0x3f]; |
|
if (pad) { |
|
out[out_pos+2] = out[out_pos+3] = padchar; |
|
out_pos += 4; |
|
} |
|
else |
|
out_pos += 2; |
|
} |
|
break; |
|
case 2: |
|
{ |
|
/* pretend in[i] = 0, don't write last (out_pos+3) character */ |
|
v = (in[i-2] << 10) | (in[i-1] << 2); |
|
out[out_pos+0] = base64_table[(v >> 12) & 0x3f]; |
|
out[out_pos+1] = base64_table[(v >> 6) & 0x3f]; |
|
out[out_pos+2] = base64_table[(v ) & 0x3f]; |
|
if (pad) { |
|
out[out_pos+3] = padchar; |
|
out_pos += 4; |
|
} |
|
else |
|
out_pos += 3; |
|
} |
|
break; |
|
} |
|
|
|
return out_pos; |
|
} |
|
|
|
|
|
char* buffer_append_base64_enc(buffer *out, const unsigned char* in, size_t in_length, base64_charset charset, int pad) { |
|
const size_t reserve = (in_length+2)/3*4; |
|
char * const result = buffer_string_prepare_append(out, reserve); |
|
const size_t out_pos = |
|
li_base64_enc(result, reserve, in, in_length, charset, pad); |
|
|
|
buffer_commit(out, out_pos); |
|
|
|
return result; |
|
} |
|
|
|
|
|
unsigned char* buffer_append_base64_decode(buffer *out, const char* in, size_t in_length, base64_charset charset) { |
|
const size_t reserve = 3*(in_length/4) + 3; |
|
unsigned char * const result = (unsigned char *) |
|
buffer_string_prepare_append(out, reserve); |
|
const size_t out_pos = |
|
li_base64_dec(result, reserve, in, in_length, charset); |
|
|
|
buffer_commit(out, out_pos); |
|
|
|
return (out_pos || !in_length) ? result : NULL; |
|
}
|
|
|