--- /dev/null
+/*
+cencoder.c - c source to a base64 encoding algorithm implementation
+
+This is part of the libb64 project, and has been placed in the public domain.
+For details, see http://sourceforge.net/projects/libb64
+*/
+
+/*
+ Modified by Eugene Crosser to fit pam_pcsc_cr project, 2013
+*/
+
+#include <string.h>
+#include <base64.h>
+/*
+cencode.h - c header for a base64 encoding algorithm
+
+This is part of the libb64 project, and has been placed in the public domain.
+For details, see http://sourceforge.net/projects/libb64
+*/
+
+/*
+ Modified by Eugene Crosser to fit pam_pcsc_cr project, 2013
+*/
+
+typedef enum
+{
+ step_A, step_B, step_C
+} base64_encodestep;
+
+typedef struct
+{
+ base64_encodestep step;
+ char result;
+ int stepcount;
+} base64_encodestate;
+
+/*
+cdecode.h - c header for a base64 decoding algorithm
+
+This is part of the libb64 project, and has been placed in the public domain.
+For details, see http://sourceforge.net/projects/libb64
+*/
+
+typedef enum
+{
+ step_a, step_b, step_c, step_d
+} base64_decodestep;
+
+typedef struct
+{
+ base64_decodestep step;
+ char plainchar;
+} base64_decodestate;
+
+static void base64_init_encodestate(base64_encodestate* state_in)
+{
+ state_in->step = step_A;
+ state_in->result = 0;
+ state_in->stepcount = 0;
+}
+
+static char base64_encode_value(char value_in)
+{
+ static const char* encoding = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+ if (value_in > 63) return '=';
+ return encoding[(int)value_in];
+}
+
+static int base64_encode_block(const char* plaintext_in, int length_in, char* code_out, base64_encodestate* state_in)
+{
+ const char* plainchar = plaintext_in;
+ const char* const plaintextend = plaintext_in + length_in;
+ char* codechar = code_out;
+ char result;
+ char fragment;
+
+ result = state_in->result;
+
+ switch (state_in->step)
+ {
+ while (1)
+ {
+ case step_A:
+ if (plainchar == plaintextend)
+ {
+ state_in->result = result;
+ state_in->step = step_A;
+ return codechar - code_out;
+ }
+ fragment = *plainchar++;
+ result = (fragment & 0x0fc) >> 2;
+ *codechar++ = base64_encode_value(result);
+ result = (fragment & 0x003) << 4;
+ case step_B:
+ if (plainchar == plaintextend)
+ {
+ state_in->result = result;
+ state_in->step = step_B;
+ return codechar - code_out;
+ }
+ fragment = *plainchar++;
+ result |= (fragment & 0x0f0) >> 4;
+ *codechar++ = base64_encode_value(result);
+ result = (fragment & 0x00f) << 2;
+ case step_C:
+ if (plainchar == plaintextend)
+ {
+ state_in->result = result;
+ state_in->step = step_C;
+ return codechar - code_out;
+ }
+ fragment = *plainchar++;
+ result |= (fragment & 0x0c0) >> 6;
+ *codechar++ = base64_encode_value(result);
+ result = (fragment & 0x03f) >> 0;
+ *codechar++ = base64_encode_value(result);
+
+ ++(state_in->stepcount);
+ }
+ }
+ /* control should not reach here */
+ return codechar - code_out;
+}
+
+static int base64_encode_blockend(char* code_out, base64_encodestate* state_in)
+{
+ char* codechar = code_out;
+
+ switch (state_in->step)
+ {
+ case step_B:
+ *codechar++ = base64_encode_value(state_in->result);
+ *codechar++ = '=';
+ *codechar++ = '=';
+ break;
+ case step_C:
+ *codechar++ = base64_encode_value(state_in->result);
+ *codechar++ = '=';
+ break;
+ case step_A:
+ break;
+ }
+ *codechar++ = '\n';
+
+ return codechar - code_out;
+}
+
+/*
+cdecoder.c - c source to a base64 decoding algorithm implementation
+
+This is part of the libb64 project, and has been placed in the public domain.
+For details, see http://sourceforge.net/projects/libb64
+*/
+
+static int base64_decode_value(char value_in)
+{
+ static const char decoding[] = {62,-1,-1,-1,63,52,53,54,55,56,57,58,59,60,61,-1,-1,-1,-2,-1,-1,-1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51};
+ static const char decoding_size = sizeof(decoding);
+ value_in -= 43;
+ if (value_in < 0 || value_in >= decoding_size) return -1;
+ return decoding[(int)value_in];
+}
+
+static void base64_init_decodestate(base64_decodestate* state_in)
+{
+ state_in->step = step_a;
+ state_in->plainchar = 0;
+}
+
+static int base64_decode_block(const char* code_in, const int length_in, char* plaintext_out, base64_decodestate* state_in)
+{
+ const char* codechar = code_in;
+ char* plainchar = plaintext_out;
+ char fragment;
+
+ *plainchar = state_in->plainchar;
+
+ switch (state_in->step)
+ {
+ while (1)
+ {
+ case step_a:
+ do {
+ if (codechar == code_in+length_in)
+ {
+ state_in->step = step_a;
+ state_in->plainchar = *plainchar;
+ return plainchar - plaintext_out;
+ }
+ fragment = (char)base64_decode_value(*codechar++);
+ } while (fragment < 0);
+ *plainchar = (fragment & 0x03f) << 2;
+ case step_b:
+ do {
+ if (codechar == code_in+length_in)
+ {
+ state_in->step = step_b;
+ state_in->plainchar = *plainchar;
+ return plainchar - plaintext_out;
+ }
+ fragment = (char)base64_decode_value(*codechar++);
+ } while (fragment < 0);
+ *plainchar++ |= (fragment & 0x030) >> 4;
+ *plainchar = (fragment & 0x00f) << 4;
+ case step_c:
+ do {
+ if (codechar == code_in+length_in)
+ {
+ state_in->step = step_c;
+ state_in->plainchar = *plainchar;
+ return plainchar - plaintext_out;
+ }
+ fragment = (char)base64_decode_value(*codechar++);
+ } while (fragment < 0);
+ *plainchar++ |= (fragment & 0x03c) >> 2;
+ *plainchar = (fragment & 0x003) << 6;
+ case step_d:
+ do {
+ if (codechar == code_in+length_in)
+ {
+ state_in->step = step_d;
+ state_in->plainchar = *plainchar;
+ return plainchar - plaintext_out;
+ }
+ fragment = (char)base64_decode_value(*codechar++);
+ } while (fragment < 0);
+ *plainchar++ |= (fragment & 0x03f);
+ }
+ }
+ /* control should not reach here */
+ return plainchar - plaintext_out;
+}
+
+int b64_encode(const char *src, const int ssize,
+ char *const b64, int *const bsize)
+{
+ base64_encodestate s;
+ int cnt1, cnt2;
+ char *c = b64;
+
+ /* FIXME check size */
+ base64_init_encodestate(&s);
+ cnt1 = base64_encode_block(src, ssize, c, &s);
+ c += cnt1;
+ cnt2 = base64_encode_blockend(c, &s);
+ c += cnt2;
+ *c = 0;
+ *bsize = cnt1 + cnt2;
+ return 0;
+}
+
+int b64_decode(const char *b64, char *const dst, int *const dsize)
+{
+ base64_decodestate s;
+ int cnt;
+
+ /* FIXME check size */
+ base64_init_decodestate(&s);
+ cnt = base64_decode_block(b64, strlen(b64), dst, &s);
+ *dsize = cnt;
+ return 0;
+}
projects / pam_pcsc_cr.git / blobdiff