base64dec: skip non-printable characters like \r\n Non-printable characters, such as line breaks, in a base64 encoded string violate the "string length must be a multiple of four" rule. This patch pads the result buffer by one extra unit of four bytes, and skips over non-printable characters found in the input string.
Suraj N. Kurapati sunaku@riseup.net
1 files changed,
12 insertions(+),
5 deletions(-)
jump to
M
st.c
→
st.c
@@ -386,6 +386,13 @@ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; +char +base64dec_getc(const char **src) +{ + while (**src && !isprint(**src)) (*src)++; + return *((*src)++); +} + char * base64dec(const char *src) {@@ -393,13 +400,13 @@ size_t in_len = strlen(src);
char *result, *dst; if (in_len % 4) - return NULL; + in_len += 4 - (in_len % 4); result = dst = xmalloc(in_len / 4 * 3 + 1); while (*src) { - int a = base64_digits[(unsigned char) *src++]; - int b = base64_digits[(unsigned char) *src++]; - int c = base64_digits[(unsigned char) *src++]; - int d = base64_digits[(unsigned char) *src++]; + int a = base64_digits[(unsigned char) base64dec_getc(&src)]; + int b = base64_digits[(unsigned char) base64dec_getc(&src)]; + int c = base64_digits[(unsigned char) base64dec_getc(&src)]; + int d = base64_digits[(unsigned char) base64dec_getc(&src)]; *dst++ = (a << 2) | ((b & 0x30) >> 4); if (c == -1)