X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=crypt.c;h=679ba35dd07d59ec184942524f8a1bb0be786939;hb=a9126f461792a84c760162ecb25100f1593d427d;hp=580974d7d74a6b97d1f4b2d6a436adc98ba7408b;hpb=20ad4f0f93da79e2ec0a9699dff58b9922556438;p=paraslash.git diff --git a/crypt.c b/crypt.c index 580974d7..679ba35d 100644 --- a/crypt.c +++ b/crypt.c @@ -6,13 +6,18 @@ /** \file crypt.c openssl-based RSA encryption/decryption routines */ +#include +#include +#include +#include +#include +#include + #include "para.h" #include "error.h" #include "string.h" #include "crypt.h" -#include -#include - +#include "fd.h" /** * Fill a buffer with random content. * @@ -218,3 +223,110 @@ int para_encrypt_challenge(RSA* rsa, long unsigned challenge_nr, return ret; } +/** + * Encrypt and send a buffer. + * + * \param rc4c The rc4 crypt context. + * \param buf The buffer to send. + * \param len The size of \a buf in bytes. + * + * \return The return value of the underyling call to write_all(). + * + * \sa \ref write_all(), RC4(3). + */ +int rc4_send_bin_buffer(struct rc4_context *rc4c, const char *buf, size_t len) +{ + int ret; + unsigned char *tmp; + + assert(len); + tmp = para_malloc(len); + RC4(&rc4c->send_key, len, (const unsigned char *)buf, tmp); + ret = write_all(rc4c->fd, (char *)tmp, &len); + free(tmp); + return ret; +} + +/** + * Encrypt and send a \p NULL-terminated buffer. + * + * \param rc4c The rc4 crypt context. + * \param buf The buffer to send. + * + * \return The return value of the underyling call to rc4_send_bin_buffer(). + */ +int rc4_send_buffer(struct rc4_context *rc4c, const char *buf) +{ + return rc4_send_bin_buffer(rc4c, buf, strlen(buf)); +} + +/** + * Format, encrypt and send a buffer. + * + * \param rc4c The rc4 crypt context. + * \param fmt A format string. + * + * \return The return value of the underyling call to rc4_send_buffer(). + */ +__printf_2_3 int rc4_send_va_buffer(struct rc4_context *rc4c, const char *fmt, ...) +{ + char *msg; + int ret; + + PARA_VSPRINTF(fmt, msg); + ret = rc4_send_buffer(rc4c, msg); + free(msg); + return ret; +} + +/** + * Receive a buffer and decrypt it. + * + * \param rc4c The rc4 crypt context. + * \param buf The buffer to write the decrypted data to. + * \param size The size of \a buf. + * + * \return The number of bytes received on success, negative on errors, zero if + * the peer has performed an orderly shutdown. + * + * \sa recv(2), RC4(3). + */ +int rc4_recv_bin_buffer(struct rc4_context *rc4c, char *buf, size_t size) +{ + unsigned char *tmp = para_malloc(size); + ssize_t ret = recv(rc4c->fd, tmp, size, 0); + + if (ret > 0) + RC4(&rc4c->recv_key, ret, tmp, (unsigned char *)buf); + else if (ret < 0) + ret = -ERRNO_TO_PARA_ERROR(errno); + free(tmp); + return ret; +} + +/** + * Receive a buffer, decrypt it and write terminating NULL byte. + * + * \param rc4c The rc4 crypt context. + * \param buf The buffer to write the decrypted data to. + * \param size The size of \a buf. + * + * Read at most \a size - 1 bytes from file descriptor given by \a rc4c, + * decrypt the received data and write a NULL byte at the end of the decrypted + * data. + * + * \return The return value of the underlying call to \ref + * rc4_recv_bin_buffer(). + */ +int rc4_recv_buffer(struct rc4_context *rc4c, char *buf, size_t size) +{ + int n; + + assert(size); + n = rc4_recv_bin_buffer(rc4c, buf, size - 1); + if (n >= 0) + buf[n] = '\0'; + else + *buf = '\0'; + return n; +}