diff options
Diffstat (limited to 'data/lighttpd/lighttpd-1.4.53/src/base64.c')
| -rw-r--r-- | data/lighttpd/lighttpd-1.4.53/src/base64.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/data/lighttpd/lighttpd-1.4.53/src/base64.c b/data/lighttpd/lighttpd-1.4.53/src/base64.c new file mode 100644 index 000000000..3034181a5 --- /dev/null +++ b/data/lighttpd/lighttpd-1.4.53/src/base64.c @@ -0,0 +1,235 @@ +#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 */ +}; + +unsigned char* buffer_append_base64_decode(buffer *out, const char* in, size_t in_length, base64_charset charset) { + unsigned char *result; + size_t out_pos = 0; /* current output character (position) that is decoded. can contain partial result */ + unsigned int group = 0; /* how many base64 digits in the current group were decoded already. each group has up to 4 digits */ + size_t i; + const signed char *base64_reverse_table; + + switch (charset) { + case BASE64_STANDARD: + base64_reverse_table = base64_standard_reverse_table; + break; + case BASE64_URL: + base64_reverse_table = base64_url_reverse_table; + break; + default: + return NULL; + } + + result = (unsigned char *) buffer_string_prepare_append(out, 3*(in_length / 4) + 3); + + /* run through the whole string, converting as we go */ + for (i = 0; i < in_length; i++) { + unsigned char c = (unsigned char) in[i]; + int ch; + + if (c == '\0') break; + if (c >= 128) return NULL; /* only 7-bit characters allowed */ + + ch = base64_reverse_table[c]; + if (-3 == ch) { + /* pad character; can only come after 2 base64 digits in a group */ + if (group < 2) return NULL; + break; + } else if (-2 == ch) { + continue; /* skip character */ + } else if (ch < 0) { + return NULL; /* invalid character, abort */ + } + + switch(group) { + case 0: + result[out_pos] = ch << 2; + group = 1; + break; + case 1: + result[out_pos++] |= ch >> 4; + result[out_pos] = (ch & 0x0f) << 4; + group = 2; + break; + case 2: + result[out_pos++] |= ch >>2; + result[out_pos] = (ch & 0x03) << 6; + group = 3; + break; + case 3: + result[out_pos++] |= ch; + group = 0; + break; + } + } + + switch(group) { + case 0: + /* ended on boundary */ + break; + case 1: + /* need at least 2 base64 digits per group */ + return NULL; + case 2: + /* have 2 base64 digits in last group => one real octect, two zeroes padded */ + case 3: + /* have 3 base64 digits in last group => two real octects, one zero padded */ + + /* for both cases the current index already is on the first zero padded octet + * - check it really is zero (overlapping bits) */ + if (0 != result[out_pos]) return NULL; + break; + } + + buffer_commit(out, out_pos); + + return result; +} + +size_t li_to_base64_no_padding(char* out, size_t out_length, const unsigned char* in, size_t in_length, base64_charset charset) { + const size_t full_tuples = in_length / 3; + const size_t in_tuple_remainder = in_length % 3; + const size_t out_tuple_remainder = in_tuple_remainder ? 1 + in_tuple_remainder : 0; + const size_t require_space = 4 * full_tuples + out_tuple_remainder; + const char* base64_table; + size_t i; + size_t out_pos = 0; + + switch (charset) { + case BASE64_STANDARD: + base64_table = base64_standard_table; + break; + case BASE64_URL: + base64_table = base64_url_table; + break; + default: + force_assert(0 && "invalid charset"); + } + + /* check overflows */ + force_assert(full_tuples <= 2*full_tuples); + force_assert(full_tuples <= 4*full_tuples); + force_assert(4*full_tuples <= 4*full_tuples + out_tuple_remainder); + force_assert(require_space <= out_length); + + for (i = 2; i < in_length; i += 3) { + unsigned int v = (in[i-2] << 16) | (in[i-1] << 8) | in[i]; + out[out_pos+3] = base64_table[v & 0x3f]; v >>= 6; + out[out_pos+2] = base64_table[v & 0x3f]; v >>= 6; + out[out_pos+1] = base64_table[v & 0x3f]; v >>= 6; + out[out_pos+0] = base64_table[v & 0x3f]; + out_pos += 4; + } + switch (in_tuple_remainder) { + case 0: + break; + case 1: + { + /* pretend in[i-1] = in[i] = 0, don't write last two (out_pos+3, out_pos+2) characters */ + unsigned int v = (in[i-2] << 4); + out[out_pos+1] = base64_table[v & 0x3f]; v >>= 6; + out[out_pos+0] = base64_table[v & 0x3f]; + out_pos += 2; + } + break; + case 2: + { + /* pretend in[i] = 0, don't write last (out_pos+3) character */ + unsigned int v = (in[i-2] << 10) | (in[i-1] << 2); + out[out_pos+2] = base64_table[v & 0x3f]; v >>= 6; + out[out_pos+1] = base64_table[v & 0x3f]; v >>= 6; + out[out_pos+0] = base64_table[v & 0x3f]; + out_pos += 3; + } + break; + } + force_assert(out_pos <= out_length); + return out_pos; +} + +size_t li_to_base64(char* out, size_t out_length, const unsigned char* in, size_t in_length, base64_charset charset) { + const size_t in_tuple_remainder = in_length % 3; + size_t padding_length = in_tuple_remainder ? 3 - in_tuple_remainder : 0; + + char padding; + size_t out_pos; + + switch (charset) { + case BASE64_STANDARD: + padding = base64_standard_table[64]; + break; + case BASE64_URL: + padding = base64_url_table[64]; + break; + default: + force_assert(0 && "invalid charset"); + } + + force_assert(out_length >= padding_length); + out_pos = li_to_base64_no_padding(out, out_length - padding_length, in, in_length, charset); + + while (padding_length > 0) { + out[out_pos++] = padding; + padding_length--; + } + + force_assert(out_pos <= out_length); + + return out_pos; +} + + +char* buffer_append_base64_encode_no_padding(buffer *out, const unsigned char* in, size_t in_length, base64_charset charset) { + size_t reserve = 4*(in_length/3) + 4; + char* result = buffer_string_prepare_append(out, reserve); + size_t out_pos = li_to_base64_no_padding(result, reserve, in, in_length, charset); + + buffer_commit(out, out_pos); + + return result; +} + +char* buffer_append_base64_encode(buffer *out, const unsigned char* in, size_t in_length, base64_charset charset) { + size_t reserve = 4*(in_length/3) + 4; + char* result = buffer_string_prepare_append(out, reserve); + size_t out_pos = li_to_base64(result, reserve, in, in_length, charset); + + buffer_commit(out, out_pos); + + return result; +} |