From 6b2ad2aa9b25c02b35ad150e29b7df7092089c4c Mon Sep 17 00:00:00 2001 From: BlackLight Date: Mon, 11 Oct 2010 17:02:38 +0200 Subject: [PATCH] (Oh, adding base64 stuff) --- base64/base64.c | 40 +++++++++++++++++ base64/cdecode.c | 88 ++++++++++++++++++++++++++++++++++++++ base64/cdecode.h | 28 ++++++++++++ base64/cencode.c | 109 +++++++++++++++++++++++++++++++++++++++++++++++ base64/cencode.h | 31 ++++++++++++++ 5 files changed, 296 insertions(+) create mode 100644 base64/base64.c create mode 100644 base64/cdecode.c create mode 100644 base64/cdecode.h create mode 100644 base64/cencode.c create mode 100644 base64/cencode.h diff --git a/base64/base64.c b/base64/base64.c new file mode 100644 index 0000000..543b8df --- /dev/null +++ b/base64/base64.c @@ -0,0 +1,40 @@ +#include +#include "cencode.h" +#include "cdecode.h" + +/** + * \brief base64-encode an input buffer + * \param in Sequence of bytes to be encoded + * \param in_len Length of the input sequence + * \param out Pointer to the buffer that will contain the output (its length must be at least 2*in_len + 1) + */ + +void +base64_encode ( const char *in, size_t in_len, char **out ) +{ + char pad[100] = { 0 }; + base64_encodestate e_state; + + base64_init_encodestate ( &e_state ); + base64_encode_block ( in, in_len, *out, &e_state ); + base64_encode_blockend ( pad, &e_state ); + + pad[ strlen(pad) - 1 ] = 0; + strcat ( *out, pad ); +} /* ----- end of function base64_encode ----- */ + +/** + * \brief base64-decode a base64 string + * \param in base64 string to be decoded + * \param out Pointer to the buffer that will contain the output (its length should be at least the same like the length of in) + */ + +void +base64_decode ( const char *in, char **out ) +{ + base64_decodestate d_state; + + base64_init_decodestate ( &d_state ); + base64_decode_block ( in, strlen ( in ), *out, &d_state ); +} /* ----- end of function base64_decode ----- */ + diff --git a/base64/cdecode.c b/base64/cdecode.c new file mode 100644 index 0000000..bb4b07c --- /dev/null +++ b/base64/cdecode.c @@ -0,0 +1,88 @@ +/* +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 +*/ + +#include "cdecode.h" + +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]; +} + +void base64_init_decodestate(base64_decodestate* state_in) +{ + state_in->step = step_a; + state_in->plainchar = 0; +} + +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; +} + diff --git a/base64/cdecode.h b/base64/cdecode.h new file mode 100644 index 0000000..d0d7f48 --- /dev/null +++ b/base64/cdecode.h @@ -0,0 +1,28 @@ +/* +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 +*/ + +#ifndef BASE64_CDECODE_H +#define BASE64_CDECODE_H + +typedef enum +{ + step_a, step_b, step_c, step_d +} base64_decodestep; + +typedef struct +{ + base64_decodestep step; + char plainchar; +} base64_decodestate; + +void base64_init_decodestate(base64_decodestate* state_in); + +int base64_decode_value(char value_in); + +int base64_decode_block(const char* code_in, const int length_in, char* plaintext_out, base64_decodestate* state_in); + +#endif /* BASE64_CDECODE_H */ diff --git a/base64/cencode.c b/base64/cencode.c new file mode 100644 index 0000000..1be5892 --- /dev/null +++ b/base64/cencode.c @@ -0,0 +1,109 @@ +/* +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 +*/ + +#include "cencode.h" + +const int CHARS_PER_LINE = 72; + +void base64_init_encodestate(base64_encodestate* state_in) +{ + state_in->step = step_A; + state_in->result = 0; + state_in->stepcount = 0; +} + +char base64_encode_value(char value_in) +{ + static const char* encoding = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + if (value_in > 63) return '='; + return encoding[(int)value_in]; +} + +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); + if (state_in->stepcount == CHARS_PER_LINE/4) + { + /* *codechar++ = '\n'; */ + state_in->stepcount = 0; + } + } + } + /* control should not reach here */ + return codechar - code_out; +} + +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; +} + diff --git a/base64/cencode.h b/base64/cencode.h new file mode 100644 index 0000000..c1e3464 --- /dev/null +++ b/base64/cencode.h @@ -0,0 +1,31 @@ +/* +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 +*/ + +#ifndef BASE64_CENCODE_H +#define BASE64_CENCODE_H + +typedef enum +{ + step_A, step_B, step_C +} base64_encodestep; + +typedef struct +{ + base64_encodestep step; + char result; + int stepcount; +} base64_encodestate; + +void base64_init_encodestate(base64_encodestate* state_in); + +char base64_encode_value(char value_in); + +int base64_encode_block(const char* plaintext_in, int length_in, char* code_out, base64_encodestate* state_in); + +int base64_encode_blockend(char* code_out, base64_encodestate* state_in); + +#endif /* BASE64_CENCODE_H */