#include <linux/errno.h> | |
/* | |
* base64 encode/decode. | |
*/ | |
const char *pem_key = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; | |
static int encode_bits(int c) | |
{ | |
return pem_key[c]; | |
} | |
static int decode_bits(char c) | |
{ | |
if (c >= 'A' && c <= 'Z') | |
return c - 'A'; | |
if (c >= 'a' && c <= 'z') | |
return c - 'a' + 26; | |
if (c >= '0' && c <= '9') | |
return c - '0' + 52; | |
if (c == '+') | |
return 62; | |
if (c == '/') | |
return 63; | |
if (c == '=') | |
return 0; /* just non-negative, please */ | |
return -EINVAL; | |
} | |
int ceph_armor(char *dst, const char *src, const char *end) | |
{ | |
int olen = 0; | |
int line = 0; | |
while (src < end) { | |
unsigned char a, b, c; | |
a = *src++; | |
*dst++ = encode_bits(a >> 2); | |
if (src < end) { | |
b = *src++; | |
*dst++ = encode_bits(((a & 3) << 4) | (b >> 4)); | |
if (src < end) { | |
c = *src++; | |
*dst++ = encode_bits(((b & 15) << 2) | | |
(c >> 6)); | |
*dst++ = encode_bits(c & 63); | |
} else { | |
*dst++ = encode_bits((b & 15) << 2); | |
*dst++ = '='; | |
} | |
} else { | |
*dst++ = encode_bits(((a & 3) << 4)); | |
*dst++ = '='; | |
*dst++ = '='; | |
} | |
olen += 4; | |
line += 4; | |
if (line == 64) { | |
line = 0; | |
*(dst++) = '\n'; | |
olen++; | |
} | |
} | |
return olen; | |
} | |
int ceph_unarmor(char *dst, const char *src, const char *end) | |
{ | |
int olen = 0; | |
while (src < end) { | |
int a, b, c, d; | |
if (src < end && src[0] == '\n') | |
src++; | |
if (src + 4 > end) | |
return -EINVAL; | |
a = decode_bits(src[0]); | |
b = decode_bits(src[1]); | |
c = decode_bits(src[2]); | |
d = decode_bits(src[3]); | |
if (a < 0 || b < 0 || c < 0 || d < 0) | |
return -EINVAL; | |
*dst++ = (a << 2) | (b >> 4); | |
if (src[2] == '=') | |
return olen + 1; | |
*dst++ = ((b & 15) << 4) | (c >> 2); | |
if (src[3] == '=') | |
return olen + 2; | |
*dst++ = ((c & 3) << 6) | d; | |
olen += 3; | |
src += 4; | |
} | |
return olen; | |
} |